Holistic Approach To Supporting Health Psychology Essay

All encompassing Approach To Supporting Health Psychology Essay Emma and Kyle live in a home having some expertise in giving 24hr consideration to youthful pregnant ladies and their infants. Emma was taken care of from being 4 yrs old when she was expelled from her folks care. She was encouraged for 10yrs by a mindful couple until disease constrained them to restore her to social consideration administrations. A few arrangements separated as Emma couldn't conform to another family and she was at last positioned in a youthful people groups grand slam by social consideration administrations when she got pregnant at 15yrs old. She went to class until the introduction of Kyle who was brought into the world a month untimely. She moved into the mother and child lodging when she was a half year pregnant after referral by her social consideration laborer. She has a decent connection with Kyle, in spite of the fact that staff say they would be concerned if she somehow happened to leave the inn and live freely. Kyle has as of late began full time nursery w hich offers Emma the chance to go to school where she contemplates providing food. Characterizing wellbeing can be a troublesome assignment. The most well known definition is that of the World Health Organization (WHO) which hasnt been altered since 1948. Wellbeing is a condition of complete physical, mental and social prosperity and not just the nonattendance of sickness or ailment (WHO 1948). There are numerous models of wellbeing that have been created throughout the years, one being the biomedical model which centers around physical indications, for example, torment. This idea deductively quantifies a people wellbeing to choose whether disease is available or not. Biomedical researchers guarantee that the body is a machine and can be fixed when a breakdown happens. An improved model would be the Biopsychosocial hypothesis which focuses on entire life issues including passionate and profound viewpoints just as social and family support. The all encompassing model improved further to incorporate physical, mental and social factors yet additionally determinants, f or example, nourishment, liquor, nicotine, rest, exercise and network life. The focal point of this report is to look at and comprehend the physical, social and mental impacts upon wellbeing by utilizing the contextual analysis and consider how things can be improved by utilizing the all encompassing methodology rather than the Biomedical and Biopsychosocial. The principal thing that will be considered in this report is intense subject matters during early stages. People who experience the ill effects of broken or passionate connections during earliest stages regularly form into grown-ups who experience issues understanding their own feelings and this may confine their capacity to keep up a fruitful relationship in later life. For the situation investigation of Emma, she was thought about by her folks till the period of 4years at that point evacuated and put into a mindful temporary family. It is conceivable that the natural family experienced useless inclinations which could mean youngster disregard or even kid maltreatment inside the home. A baby raised inside this condition would envision it to be typical conduct consequently being set in what society sees as an ordinary working family, would be hard to change in accordance with. A few examinations propose that up to 80% of youngsters in child care have huge psychological well-being is sues because of the injury of partition from the organic family notwithstanding encounters of useless families (Smariga 2007). At the point when a kid is isolated from their essential guardian who is normally the mother, partition nervousness can happen. Newborn children more youthful than 4 years are especially powerless and will encounter significant levels of passionate unsettling influences. Division nervousness in babies can be treated with play treatment whenever perceived early enough. This sort of treatment is a type of guiding which assists small kids utilize elective adapting procedures to working through any current issues and is presumably the more preferred model estimated by biopsychosocial advisors. Nonetheless, biomedical specialists accept that an irregularity in synapses is the reason for nervousness and other mental issue, for example, wretchedness and will suggest the youngster take a gentle narcotic to help lessen the injury (Ponton 2006). The comprehensive model would contend that specific determinants assume a significant job in distinguishing and rewarding uneasiness. Sustenance is im perative as food impacts the equalization of synthetic compounds delivered and discharged in the cerebrum in this way, without adequate protein, the mind can get lacking in specific synthetic substances, bringing about nervousness and melancholy. Exercise is likewise significant as again this discharges synthetic concoctions, for example, endorphins and serotonin which give a vibe decent impact (livestrong 2012) Despondency is a typical issue and females are twice as prone to endure sooner or later in their lives as guys. This is basically because of changes in hormones in youthfulness. Biomedical specialists accept that these progressions are clear during adolescence and pregnancy just as subsequent to conceiving an offspring. As indicated by the National Institute of Health, factors that expansion the danger of gloom in ladies incorporate conceptive, hereditary, or other organic components. Also, ladies who shuffle work with raising a family and single guardians endure more pressure that may trigger side effects of misery (NIMH). A biomedical view is analyze and treat despondency by recommending antidepressants. These kinds of drugs increment the degrees of serotonin inside the body which proceed to build joy. Late investigations propose that reactions welcomed on by long haul utilization of antidepressants can incorporate stomach related issues, sexual challenges and even strokes and unex pected losses in more established individuals. Medications that meddle with serotonin may cause formative issues in babies, advancement in grown-ups, stomach related issues, looseness of the bowels, and acid reflux and may likewise raise the danger of dementia (Naish 2012). There are various comprehensive techniques which can help monitor sadness, for example, maintaining a strategic distance from caffeine, nourishment and exercise. Caffeine diminishes serotonin levels so lessening the medication will normally expand bliss. Basic fats can't be normally created in the human body in this manner it is significant that they are remembered for the eating routine. The most extravagant wellspring of omega 3 is found in sleek fish and nuts. A considerable lot of the populace are on low pay or benefits and perhaps observe themselves to not be in a position monetarily to eat new food. Eating shoddy nourishment will build the degrees of sugar found in the blood which will give side effects of weakness, touchiness, tipsiness, sleep deprivation, despondency and stomach related issues. Since the cerebrum relies upon an even gracefully of glucose it is of nothing unexpected to find that the above side effects can show up. The most ideal approach to keep your glucose level even is to eat entire nourishments, natural products, vegetables, and ordinary suppers (Food for the mind 2012) A few youngsters will endure with direct disarranges, for example, hostility, robbery, trickiness or infringement of rules. This can mess up school and in the family home which can prompt police association. Causes can create from personality, hereditary qualities (normal in offspring of grown-ups who had direct issues), natural (family issues and social weights) or physical (issues in preparing data). Outrage influences your physical wellbeing and can cause hypertension, constant lower back torment, stomach issues and coronary illness. The biomedical view is treat every manifestation exclusively with medicine where as an increasingly all encompassing strategy is practice unwinding methods, taking part in physical exercise or by accomplishing something that connects with the psyche, for example, drawing or painting. Another approach to deal with this would guide. Gathering treatment is a great choice for young people to gain from each other and social collaboration is a crucial piece of the formative procedure. Immature years can be trying for guardians or experts. Characters are framing, public activities are extending and new practices are tried different things with. This can include liquor, tobacco, drugs and dangerous sexual movement. An individual who is inebriated is bound to participate in unprotected sex with an assortment of sexual accomplices. The proceeded with utilization of any substance can prompt substance misuse and dependence. Emma fell pregnant at 15yrs which might be a consequence of exorbitant liquor or medications. A creating infant is presented to whatever is placed into the framework so no protected measure of liquor, tobacco or medications exists during pregnancy. Nicotine is a vasoconstrictor which makes the veins tight constraining the progression of blood to the infant. Additionally carbon monoxide will constrain the degrees of oxygen accessible to the baby which can bring about still birth, low birth weight or unexpected newborn child passing disorder (livestron g 2012). The National Institute of Health prompts pregnant ladies not to drink during the first3 month specifically as this may actuate unnatural birth cycle (NHS 2012) Another type of melancholy is postnatal sadness (PND) which is basic in the two people. PND is distinctive to misery and the beginning as a rule happens after the introduction of a child yet can likewise show up during pregnancy. Ladies can turn out to be more mournful and moodier than expected in this time. A few ladies experience considerations of hurting their child which is very regular influencing practically 50% of ladies with the condition (Roberts 2012). PND can be undetected and left untreated which may prompt animosity and conceivable damage to the child. Adolescent moms experience the ill effects of less fortunate emotional wellness in the three years after their introduction to the world contrasted and different moms subsequently Emma needs as much help as possible conceivably get during the early long stretches of being a mother. She has no family around to help and help her. The sentiment of detachment is the most upsetting part of being a mother. Comprehensive treatmen ts can be useful to battle the pressure of being another mother as well as a young and single parent. Back rub, reflexology and home grown cures might be helpful to help in unwinding. Talking treatments are additionally exceptionally mainstream and can help with distinguishing

Nclex Hesi Practice Tests free essay sample

Disavowal B. Outrage C. Haggling D. Dismissal 2. Which of the accompanying matches the definition: concealing a shortcoming by focusing on an attractive or more grounded characteristic? A. Remuneration B. Projection C. Defense D. Dysphoria 3. Which of the accompanying waveforms is most regularly found with light sleepers? A. Theta B. Alpha C. Beta D. Zeta 4. Which of the next months matches with a baby initially being able to sit-up autonomously? A. 4 months B. a half year C. 8 months D. 10 months 5. Item lastingness for babies creates in this age extend? A. 5-10 months B. 10-14 months C. 12 two years D. 15 two years 6. Which of the accompanying matches the definition: crediting of our own undesirable characteristic onto someone else? A. Pay B. Projection C. Defense D. Dysphoria 7. Which of the accompanying matches the definition: the avocation of practices utilizing reason other than the genuine explanation? A. Remuneration B. Projection C. Justification D. Dysphoria 8. Which of the accompanying matches the definition: reaction to extreme feeling pressure bringing about automatic unsettling influence of physical capacities? A. We will compose a custom exposition test on Nclex Hesi Practice Tests or then again any comparable subject explicitly for you Don't WasteYour Time Recruit WRITER Just 13.90/page Transformation issue B. Burdensome response C. Bipolar confusion D. Alzheimers sickness 9. Which of the accompanying waveforms is most generally discovered when you are wakeful? A. Theta B. Alpha C. Beta D. Zeta 10. The REM rest cycle happen roughly every ____ minutes? A. 45 B. 60 C. 75 D. 90 11. Which of the accompanying reflexes isn't found during childbirth? A. Babinski B. Palmar C. Moro D. Flexion 12. Equal play for babies creates in this age go? A. 5-10 months B. 10-14 months C. 12 two years D. 24 four years 13. Which of coming up next is certifiably not an indication of nervousness? A. Dyspnea B. Hyperventilation C. Sodden mouth D. GI side effects 14. Which of the accompanying best depicts an individual that is totally alert nodding off precipitously? A. Cataplexy B. Narcolepsy C. Transitional rest D. REM nonappearance 15. Which of the accompanying best depicts an individual that can't let you know were there hand or foot is? A. Autotopagnosia B. Cataplexy C. Ergophobia D. Anosognosia 16. Which of coming up next is certifiably not an attribute of a frenzy issue? A. Queasiness B. Extreme sweat C. Pee D. Chest torment 17. Which of the accompanying classifications would a multi year old grown-up be put in? A. Closeness versus Segregation B. Generativitiy versus Stagnation C. Honesty versus Sadness D. Life span versus Blame 18. Which of the accompanying classes would a multi year old grown-up be set in? A. Closeness versus Disconnection B. Generativitiy versus Stagnation C. Respectability versus Gloom D. Life span versus Blame 19. Which of the accompanying classifications would a multi year old grown-up be set in? A. Closeness versus Disengagement B. Generativitiy versus Stagnation C. Uprightness versus Depression D. Life span

Automated data reconciliation of the clinical and safety databases Thesis

Mechanized information compromise of the clinical and security databases - Thesis Example It spares time, and all the more significantly, disposes of potential errors between databases. At whatever point disparities are conceivable, it requires additional quality affirmation ventures for settling befuddles (Zhengwu Lu, and Lu, Zhengwu, 2009). Genuine Adverse Event, SAE, and Adverse Event, AE, compromise analyzes explicit information between two databases; a clinical database and a security database. A clinical database characterized as s shut framework while a wellbeing database as an open framework. A clinical database can audit information for just a brief timeframe period that is enduring of the preliminary, consequently characterized as shut. A security database then again, is an open framework because of its ceaseless gathering of new SAEs or updates of SAEs that as of now exist concerning any clinical preliminaries in any event, when they are bolted (Van et al 2012). Information the board plays out the undertaking of SAE and AE compromise. Two divisions are regularly included, the pharmacovigilance and medication wellbeing, and clinical information science. During the information compromise, SAE is gathered in the security database and in the clinical database. Information cleaning happens as per the particulars of information approval (Dwivedi and IGI Global, 2009). SAE compromise is performed ceaselessly between first patient first visit, FPFV, and last patient last visit, LPLV. The explanation behind such opportune exhibitions gives information that is solid and dependable, that is of significantly valuable in dynamic procedures on a drug’s security profile and progressive preliminary structure. It likewise guarantees consistency in answering to wellbeing specialists with respect to singular Safety reports, New Drug Application, and the yearly Investigational New Drug Update (Trasi, 1994). The range of abilities open in the information the board segment, numerous extra things should be possible. The inside gifts of the area are not completely used. It isn't satisfying for people and the association. The possibilities and the requests are there.

Essay Topics For Shakespeare Sonnets

Essay Topics For Shakespeare SonnetsAre you wondering how to choose the right essay topics for your Shakespeare sonnets? In general, each individual can provide different sets of essay topics for every topic they want to tackle. We can use our own personal experiences as examples to help us in determining the best essay topics for each of our interests and values.One of the topics that is very popular with many individuals is to do with how to deal with a crisis, as it relates to the topic of life. While many individuals don't really like to be touched by a crisis, others will enjoy a calm day or night more than the time when they are faced with a crisis. The topic of life crises, such as divorce, loss of a loved one, death of a loved one, or disease, is a topic that will definitely catch the attention of many individuals and will often be discussed in relation to the essay topics for Shakespeare sonnets. Of course, if you choose an essay topic of this type, there will be many writer s who will provide examples of life crises that are similar to our own personal experiences.Life lessons are also another theme that is quite popular, as they relate to how to deal with life. A whole host of different individuals want to learn how to deal with life's struggles, problems, and dilemmas, and want to learn how to deal with these issues in a way that is harmonious and wise. In most cases, these people want to learn what to do in times of difficulty, while still keeping their roots firmly planted. This is an area where we can use our personal experiences to illustrate how life's issues can be dealt with, while remaining harmonious.An important part of the subject of the essays is the topic that will clearly portray how we respond to challenges, frustrations, and obstacles that may arise, in our lives. If we find ourselves enduring hardships and being challenged in our lives, it can be beneficial to look at some of the best ideas from writers such as William Shakespeare. M any of the greatest books and plays include stories from Shakespeare, which are effective in illustrating how we deal with problems.It is very important to look at the writers, and other writers, who have had some success in dealing with these interesting essay topics. We can ask for their insight on how they handle the challenges of life, and what sort of sources they find to support them. It is important to use the writings of writers such as Thomas Hardy, Nicholas Sparks, and others, because they have already done the research to show us how we can better deal with difficult situations, in our lives.However, this does not mean that each individual will be exposed to all of the best ideas in regards to personal experiences. There will be individuals who will have more successful writing abilities than others, simply because they have more experience. Regardless of whether we utilize the opinions of experts or receive personal experience, there are always topics that will be presen t in each essay.By combining several of the subjects that are available to us as individuals, the essay topics can greatly be helpful in coming up with the best essay topics for your Shakespeare sonnets. This can be used as a guide to help you with the essay topics for your sonnets. As many individuals consider this topic, it can make a big difference in the way your sonnets turn out.

Animals want People to Stop the Cruelty - 541 Words

Animal cruelty has been going on for years at a time. With the illegal hunting of animals and cruel test given upon them it makes you wonder if anybody really cares about what is being done to animals. Author of â€Å"Animal Rights, Human Wrongs†, Tom Regan, discusses the cruelty of what several animals go through and what people are doing about it. In this selection Regan tries to appeal to the emotions of the reader, gives facts on the things that are being done by people to animals, and tries to establish his credibility in the reading. Though Tom Regan writes about an important topic, there is very little credibility shown throughout the document. When discussing the whaling incident, Regan takes the account of an unknown man whose name is not even mentioned throughout the reading. It is also unknown if this person is someone trustworthy enough to give a truthful statement about what really happened during the whale hunt situation. The same thing happens again when Regan gives an example of another person experience with how cruel people are to animals this time dealing with the gibbon. The person who described what happened during the hunt to Regan name was given, but we have no knowledge of if this person is trustworthy enough to give an accurate account on what happened to the gibbon. Throughout the reading Regan gives more examples of the inhuman practices that happen to animals but with very little ethos to back up his claims, readers may not think of him as accountableShow MoreRelatedA Bibliography Of Animal Cruelty1696 Words   |  7 Pages Animal Cruelty By: Lily Rosenzweig Table of Contents: Chapter 1: Animal Cruelty Chapter 2: Anya Agarwal Chapter 3: Animal Homelessness Chapter 4: Animal abuse Chapter 5: What Can You Do? 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By animal testing, the companies not only violate the animals rights (which is breaking the law), but their testing methods are hazardous which endanger the animals life. Finally, the companies should stop animal testing because each year we lose hundreds of thousands of animals and could make a difference by stopping this cruelty. Stop the animal testing, and save a life. To start with, cosmetic and drug companies should stop animal testing their

Differences Between Minority And Minority Minorities

Social life has one thing that has remained constant throughout past years: change. With such a fluid society, it is projected that the United States today will shift from a â€Å"majority-minority† to a â€Å"minority-majority† society by 2042 (Stoll, 2009). â€Å"In 2010, whites accounted for about 70% of the U.S. population, but this percentage continues to decline (Jones Dovidio, 2014)†. How would this radical change impact the newly considered minority? Would such a dramatic change in the racial divide change the way â€Å"privilege† is viewed? Throughout history there has been friction between minorities and majorities. The â€Å"superior† group has advantages while the â€Å"inferior† group experiences disadvantages. The trouble with literature on majority-minority is the variation in definitions. In reference to this paper, the term minority will be a measure of numerical underrepresented ethnic population (Jones Dovidio, 2014). Now looking at previous literature covering this topic many illuminate on persuasion, minority influence, group development, Social Identity Theory, and conformity (Prislin et al, 2000; Legrenzi et al., 1991; Kelly, 1990). Prislin et al. provide a particularly useful study examining the effects of the loss and gain of majority status position within a group. Prislin et al. (2000) study results confirmed that there were greater effects of losing rather than gaining a majority position using 181 undergraduate students. Of those students 86 identified as White, 38Show MoreRelatedDiffe rences Between Minority And Minority Groups1443 Words   |  6 PagesAbstract This study explores the relationships between majority and minority groups and their awareness of blatant and subtle prejudice, by priming either common or dual identity. It was hypothesized that due to their marginalization, minority groups will be more aware of both subtle and blatant prejudice and that those primed with dual identity will show a similar heightened awareness. The results demonstrated that majority groups were more aware of both types of prejudice, contradicting many previousRead MoreDifferences Between Minority And White Students885 Words   |  4 Pagesstyle of education – the Knowledge is Power Program, or KIPP. They created the first KIPP school in Houston, Texas to better educate and motivate low-income, minority students. Eventually, their small grassroots idea grew into a network of 183 charter schools across the United States. Levin and Feinberg’s goal to close the gap between minority and white students is reflected in the fact that 87% of their students come from lower-class families and 95% are African American or Latino (â€Å"KIPP†). TheRead MoreDifferences Between Minority And Non Minority Small Business Owners Approach Succession Planning1210 Words   |  5 PagesThe aim of this quantitative correlational study is to understand the differences between how minority and non-minority small business owners’ approach succession planning. This study will use a ex-post facto design. An A priori power analysis test using the G*Power 3.1.9.2 software program will be used to establish a minimum overall sample size of 134. Specifically, a Wilcoxon –Mann-Whitney (two groups) statistical two-tailed t-test calculation with an effect size d of .5, an alpha level of .05Read MoreRelationship Values Between Gender And Sexuality Essay1181 Words   |  5 PagesRelationship values between gender and sexuality Gender is known as the set of expectations and norms linked to how men and women, and boys and girls, should act. Sexuality which refers to the biological characteristics that define men and women. Relationship values are what you believe in and morals that you hold important to you so you can live your life to the fullest. Your values are based on what you have experienced through your life and what you have learned over the years. Gender and sexualRead MoreAnalysis Of The Book Just Mercy By Bryan Stevenson972 Words   |  4 PagesLaw enforcement and minorities have long been the focus of the criminal justice injustice within the United States. African Americans, Arab Americans, Asian Americans, Native Americans, Hispanic and Latino Americans are a number of communities in the United States along with Caucasian or non-minorities as a whole, which make up a large portion of the United States. Racial discrimination has been a large factor the criminal justice system has been plague d with for many years. 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Often times in American history, unselected natural characteristics such as race and ethnicity have served as keen factors permitting unequal treatment of individuals and at creating barriers placing minority gr oups at a disadvantage when attempting to practice influence over the government. â€Å"Race has been a long-standing and stubborn dividing line in local, state, and national politics in the United States† (Rogers 6). Because of such instances, todayRead MoreConflict Between The Citizens And Police1519 Words   |  7 Pagesconflicts between the citizens and police in the past. Numerous investigations made regarding these conflicts have occurred, with the Kerner Commission being formulated to investigate the cause of this disorder. The commission reported that the conflict was caused by distrust and hostility between the police and minorities. The commission recommended that the government should hire more police from the minority groups and that would change the state of things significantly. The hiring of minority groupsRead MoreThe Brewton Berrys Model Of Assimilation984 Words   |  4 Pagesa process by which minority and majority groups are merged into some total societ al unit. There are also three different type of assimilation which are Anglo (or dominant group) conformity, the Melting Pot, and cultural pluralism. Some additional concepts that go along with assimilation are acculturation where the minority adopts the dominant culture, amalgamation the biological blending of the groups, and the transmuting pot where the dominant group selects aspects of minority culture and modifiesRead MoreThe Glass Ceiling Theory : Women And Minorities864 Words   |  4 PagesIn the past women and minorities have dealt with several obstacles that has prevented them from becoming leaders in organizations. According to Sanchez-Hucles and Davis (2010), women and minorities have experienced discrimination and biases that has prevented them from achieving and performing in leadership roles. Fortunately, both women and minorities have come a long way since that time. The glass ceiling theory that has been preventing so many women from achieving leadership roles has been cracked

Entry Barriers of Global Marketing free essay sample

Entry Barriers in Global Marketing An understanding of the entry barriers to internationalization and their effect on entry mode selection is important because they can assist in determining why global marketers are unable to exploit their full potential and why many firms fail or incur financial losses in their international activities. The height and nature of market entry barriers directly influence the entry mode chosen by a company. Entry barriers increase the cost of entry and constraint the option available, and where they are high, the company might have only one choice of entry mode or else have to stay out. The concept of entry barriers comes from the economics of industrial organization. It generally connotes any obstacle making it more difficult for a firm to enter a product market. Thus entry barriers exist at home, as when limited self space prohibits a company from acquiring sufficient retail coverage to enter a market. We will write a custom essay sample on Entry Barriers of Global Marketing or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page Overseas it can mean that customs procedures are so lengthy that they prohibit at importer’s fresh produces from getting to the stores before spoiling. In global marketing it is convenient to classify the entry barriers according to their origin. Although gradually less important because of dramatic improvements in technology, transportation costs sometimes force new investment in manufacturing to be close to the market. Proximity of supplies and service still matters when transportation costs are high. Tariff barriers are obvious obstacles to entry into the country. Less visible non-tariff barriers for example slow custom procedures, special product tests for imports and bureaucratic inertia in processing import licenses can also make entry difficult. Government regulations of business, domestic as well as foreign, constitute another set of market barriers, sometimes creating local monopolies. A special subset of these barriers is regulations directly intended to protect domestic business against foreign competitors. Other barriers are more subtle. Access to manufacturing technology and process, component suppliers and distribution channels can be restricted by regulation, territorial restrictions, competitive collusions, or close ties between transacting partners. These barriers constitute artificial value chain imperfections and become very important for the marketer to consider when deciding the configuration of the overseas operation. There are natural entry barriers that arise because of competitive actions. Many of typical marketing efforts- creating of brand loyalty, differentiation between products, high levels of promotional spending- are factors that, when successful, lead to barriers or defenses against competitive attack. Reasons to use entry barriers Global marketing increases the number of goods that domestic consumers can choose from, decreases the cost of those goods through increased competition, and allows domestic industries to ship their products abroad. While all of these seem beneficial, free trade isnt widely accepted as completely beneficial to all parties. Entry barriers or trade barriers are often  created to protect infant industry and developing economies, but are also used by more advanced economies with developed industries. Here are five of the top reasons trade barriers are used: I. Protecting Domestic Employment: The possibility of increased competition from imported goods can threaten domestic industries. These domestic companies may fire workers or shift production abroad to cut costs, which means higher unemployment and a less happy electorate. The unemployment argument often shifts to domestic industries complaining about cheap foreign labor, and how poor working conditions and lack of regulation allow foreign companies to produce goods more cheaply. II. Protecting Consumers : A government may levy a tariff on products that it feels could endanger its population. For example, South Korea may place a tariff on imported beef from the United States if it thinks that the goods could be tainted with disease. III. Infant Industries: The use of tariffs to protect infant industries can be seen by the Import Substitution Industrialization (ISI) strategy employed by many developing nations. The government of a developing economy will levy tariffs on imported goods in industries in which  it wants to foster growth. This increases the prices of imported goods and creates a domestic market for domestically produced goods, while protecting those industries from being forced out by more competitive pricing. It decreases unemployment and allows developing countries to shift from agricultural products to finished goods. IV. National Security: Barriers are also employed by developed countries to protect certain industries that are deemed strategically important, such as those supporting national security. Defense industries are often viewed as vital to state interests, and often enjoy significant levels of protection

The Tomb Of Tutankhamen Essays - Egyptian Gods, Egyptian Mythology

The Tomb of Tutankhamen The Tomb of Tutankhamen What does the tomb of tutankhamen and its contents show about the Egyptian concern for the afterlife? Tutakhamen's tomb, and the artifacts inside are an indication of the concern the Ancient Egyptians held for the after-life of their king. In 26th Nov. 1922, the English archaeologist Howard Carter opened the virtually intact tomb of a largely unknown pharaoh: Tutankhamen. This was the first, and to date the finest royal tomb found virtually intact in the history of Egyptology. It took almost a decade of meticulous and painstaking work to empty the tomb of Tutankhamen. Around 3500 individual items were recovered. When the Burial Chamber of Tutankhamen was officially opened, on 17 February 1923, the Antechamber had been emptied. It had taken near fifty days to empty the Antechamber; the time required to dismantle and restore the contents of the Burial Chamber including the gilded wooden and the sarcophagus was to be greater, and the work was not completed until November 1930, eight years after the original discovery. One must examine both the tomb itself, and its contents, to see the connection between the tombs and burial rituals and the doctrine of eternal life. The royal tombs were not merely homes in the hereafter for the kings, as are the private tombs of commoners and nobility. Instead the tombs are cosmological vehicles of rebirth and deification as much as "houses of eternity." As the king is supposed to become Osiris in a far more intimate way than commoners, he is equipped with his very own Underworld. And as the king is supposed to become R in a way entirely unavailable to commoners, he is equipped with his very own passage of the sun, whether this is thought of as the way through the underworld or through the heavens. Tutankhamon's tomb, hurriedly prepared for the premature death of the king at the age of only about 18, is, as Romer says, a "hole in the ground," compared to a proper royal tomb. The theme of fours is conspicuous in Egyptian religious practice. Tutankhamon's tomb contains four chambers. The burial chamber, with a ritual if not an actual orientation towards the West, is the chamber of departure towards the funeral destinies. The internment of the body certainly is the beginning of the sojourn of the dead, and the Egyptians saw the dead as departing"into the West." The room called the "Treasury" is then interpreted to have a ritual orientation towards the North as the "chamber of reconstitution of the body." Since the most conspicuous object in the Treasury was a great gilt sledge holding the shrine containing the canopic chest, which holds the king's viscera, this could well suggest the problem of reassembling the king's living body. That task, indeed, has a very important place in Egyptian mythology. After the goddess Isis had retrieved her husband Osiris's murdered body from Byblos, their common brother, Seth, the original murderer, stole the body, cut it into pieces, and tossed them in the Nile. Isis then had to retrieve the parts of the body before Osiris could be restored to life. Her search through the Delta, which is in the North of Egypt, seems to parallel the "sacred pilgrimage" to cities of the Delta that Desroches-Noblecourt relates as one of ritual acts of the funeral, as many of the other objects in the Treasury seem to be accessories for that pilgrimage. For the sovereign to be reborn it was necessary that a symbolic pilgrimage be made to the holy cities of the delta. The principal halts of the journey corresponded almost exactly to the four cardinal points of the delta where these cities were situated. Sais, to the west, represented the necropolis where the body was buried; Buto to the north, with its famous canal, was an essential stage of the transformations within the aquatic world of the primordial abyss, evoking the water surrounding the unborn child; and Mendes to the east whose name could be written with the two pillars of Osiris, the djed pillars, evoking the concept of air. There, said the old texts, the gods Shu and Tefenet were reunited, or again, according to the 17th chapter of The Book of the Dead, that was where the souls of Osiris and Re had joined. Finally, the southern-most city which completed the cycle of Heliopolis, the city of the sun, symbolizing the fourth [sic] element, fire, where the heavenly body arose in youth glory between the two hills on the horizon. [Christiane Desroches-Noblecourt, 1963, p. 238-9] As these four cities parallel the four rooms

7 Types of Headline Headaches

7 Types of Headline Headaches 7 Types of Headline Headaches 7 Types of Headline Headaches By Mark Nichol Throughout the history of journalism, headlines have evolved as a method for distilling the content of an article into a handful of words that will draw readers into the piece, and they serve that function for other types of informative content such as newsletters and reports. However, in publications that are not carefully edited, especially on post-it-right-now websites, headlines can invite the wrong kind of curiosity, combined with confusion or derision, when they’re published with errors. This post examines various types of common mistakes. 1. Poor Grammar This subheadline, under a headline about cell phone antennas, starts with a dangling modifier: â€Å"Numbering Over 2,400 in City Alone, Neighborhoods Say ‘Enough Is Enough.’† (The sentence construction implies that the figure refers to the number of neighborhoods.) The subject should be repeated (preferably, with elegant variation), and the quote must be preceded by a comma: â€Å"Towers Number 2,400 in the City Alone, and Neighborhoods Say, ‘Enough Is Enough.’† 2. Awkward Syntax â€Å"Man Throws Woman Off Overpass, Then Self† isn’t wrong, and it could be argued that the suicide part of the suicide-murder is the key point, but the headline is clumsy and is better rendered â€Å"Man Throws Woman, Then Self, Off Overpass.† And the literal meaning of â€Å"Man Accused of Putting Bodies in Barrels in Court† is that the off-putting putting took place in the courtroom; this misplaced modifier is easily corrected: â€Å"Man Accused of Putting Bodies in Barrels Appears in Court.† 3. Incorrect Usage A common error is perpetrated in â€Å"Less Drinking-Related Problems Reported at College.† (The problems are quantifiable, so fewer is the correct word choice.) In â€Å"VW to end making bugs in Mexico,† capitalized in sentence style rather than headline style, the choice of the first verb is awkward (stop is better), and Bugs, though a nickname for a brand name, is still a name and should be capitalized. 4. Redundancy Repetitive wording is rare in headlines, but when money is concerned, headline writers can become careless, as in â€Å"Get $100 Bucks for Recycling Old Computer Gear† and â€Å"$1.4 Million Dollars Later, No Progress.† (This type of error shows up in the articles themselves, too, as in â€Å"Taxpayers spent $1.4 billion dollars on everything from staffing, housing, flying, and entertaining President Obama and his family last year.† There’s also a parallelism error in the list; the sentence should read something like, â€Å"Taxpayers spent $1.4 billion on everything from providing staffing for President Obama and his family last year to housing, flying, and entertaining them during that period.†) 5. Misspelling Periodicals pride themselves on factual accuracy, but misspelling familiar names is an unfortunately common occurrence, as in â€Å"Jennifer Anniston Talks About Having Babies† (her last name is spelled Aniston) and â€Å"Smith Is the Michaelangelo of Real Estate† (the artist’s name is styled Michelangelo). 6. Incorrect Punctuation An article headlined â€Å"To Some Graffiti Is Art, Others Its Vandalism† not only omits a pair of commas and an apostrophe and flubs another punctuation mark but also leaves out a word; it should be â€Å"To Some, Graffiti Is Art; to Others, It’s Vandalism.† Another headline also lacks an apostrophe: â€Å"Officials Past Helps Him Plan the Future,† where officials is treated as a plural rather than in singular possessive form. 7. Erroneous Use or Lack of Hyphenation Gratuitous hyphenation, such as that in the headline â€Å"Soldier Guilty in Parachute-Tampering† the hyphen is appropriate only if â€Å"parachute-tampering† is a phrasal adjective preceding a noun such as case is annoying but innocuous, but the mangling of the age range in â€Å"Most 18-29 Year-Olds Sleep with Their Smartphones† (correction: â€Å"Most 18- to 29-Year-Olds Sleep with Their Smartphones†) is embarrassing. Nor does erroneous omission of hyphens in standing phrases reflect the rigorous quality control that assures readers of a newspaper’s accuracy; â€Å"Cease Fire in Liberia† and â€Å"Debate Free for All† should read â€Å"Cease-Fire in Liberia† and â€Å"Debate Free-for-All.† Want to improve your English in five minutes a day? Get a subscription and start receiving our writing tips and exercises daily! Keep learning! Browse the Business Writing category, check our popular posts, or choose a related post below:100 Words for Facial ExpressionsRunning Amok or Running Amuck?5 Tips to Understand Hyphenated Words

How would you suggest this should be done Are any of these subsystems Assignment

How would you suggest this should be done Are any of these subsystems more or less important than any others - Assignment Example For example, it will be impossible to attain the mission of an organization without having a clear vision and/ or objective. Examples of subsystems within organizations include goals and values subsystem, human resources subsystems, information and intelligence subsystem, technical subsystem, managerial subsystem and structural subsystem. According to Baskerville and Spagnoletti (2013), the continual interaction between various subsystems creates a pattern that specify what the main system looks like and therefore, it is impossible to gauge the main organizational system by over passing a particular subsystem since the main system relies on interdependent sub-systems. Therefore, when trying to evaluate the strengths and weaknesses of an organization it is a must for all the subsystems to be considered since an organizational is a functional unit that can only operate smoothly with the co-operation and co-ordination of various subsystems which are interdependent to each other. This is to mean that no sub-system is more or less important than the other since an organization cannot operate without a single subsystem missing and hence the evaluation should consider the strengths and weakness of each subsystem in the

International Business - Change Management Case Study

International Business - Change Management - Case Study Example It has won the following awards: the Northern Ireland Quality Award (twice); the Supreme Irish Quality Award; the parent company's overall quality award (four times); and the British Quality Award. With a turnover f around 258 million, it is among the top 10 companies in Northern Ireland, and is viewed as an exemplar by many local organizations. In addition, BTNI is one f the few companies in Ulster to have undertaken both TQM and large-scale BPR. The need for effective change management dates back to the mid-1980s when the parent company was privatized. Its former monopoly status and Civil Service ethos did little to equip the company to survive and prosper in a market-place which was changing at a rapid rate and becoming increasingly competitive. It quickly became apparent that a new culture, skills and value system were needed--the customer could no longer remain out f sight and out f mind'. Accordingly, this subsidiary, which with around 2600 employees is the smallest f the nine geographical zones' that together cover the whole f the UK, began its formal total quality journey in 1986. Senior management, with involvement from the corporate chief executive office, drew up the company's vision statement and quality policy, and its first cost f quality exercise was undertaken. This revealed that BTNI was overmanned, inefficient and expensive. Benchmarking exercises indicated that BT had approximately 10 times more staff than some f its major competitors. At this point the company could be described as being in crisis'. Its response to this crisis is interesting and informative. Response to crisis. Many writers believe that companies which regard themselves as being in crisis have no option but to re-engineer. It is also argued that the potential risks f BPR make it a last option for businesses, used only for company turnaround. Ryan (1994), for example, states that, in reality, crisis is the necessary trigger to push companies into such radical change. Talwar (1993) takes the opposite view, arguing that high-performing companies are more likely to undertake BPR. This is consistent with Bashein et al. (1994), who consider that re-engineering in a crisis may be inappropriate, as crisis can promote fear and even panic, neither f which is conducive to focused BPR. At BTNI, rather than immediately rushing into re-engineering, senior management developed a complex and long-term change strategy, key elements f which were BS 5750/ISO 9000 accreditation, total quality and, finally, process re-engineering. BTNI's improvement journey. Once the vision statement and quality policy were in place, a Quality Council was established to drive the company's improvement efforts. Figure 1, which maps the company's improvement journey, is revealing. As can be seen, early moves towards TQM in the mid-1980s proved less than successful, when compared with the rate f improvement achieved after BS 5750 accreditation. This was awarded for the company's maintenance operations in 1988/89 and for installation in 1991, followed by ISO 9001 accreditation for all parts f the company in 1993. BTNI's experience is consistent with

Disaster in Franklin County Essay Example for Free

Disaster in Franklin County Essay The role of the major public health personnel, including the public health nurse, is to provide the public with accurate information, and to assure the community, as well as ensure the immediate safety and well-being of the members of the community, while being competent compassionate and accessible. The public health director was contacted by the incident commander to attend the incident briefing due to immediate and long term public health impacts. The fire chief gave report concerning how many people were confirmed dead, what time it occurred and what county(s) were affected. He made the public aware if any hazardous materials had been released and where and whether the hazardous materials team had been dispatched. He also notifies the community of areas of flooding, and any impassable roads and the roads that are closed, as well as any power outages, and possible long term problems that may occur from power loss such as water contamination, and food loss due to spoilage. The fire chief also informs the public that the plan for search and rescue has been initiated. The public health staff had previously had National Incident Management System (NIMS) training. The deputy director sets up the incident command center and does the head count of available responders. The most ideal personnel were not totally available; there were an appropriate number to set up section chiefs and command staff. The chain of command that was used in the simulation consisted of the Public Health Team which included the County Public Health Director, Environmental Health Specialists, and Community Health Nurses, as well as Franklin county staff members, mental health, and social workers, which allowed the community health nurse to have resources available that were used to deal with situations that were outside the nurse’s scope of practice included reporting to EOC well treatment hazardous waste removal. Actions taken by the community health nurse when she encountered possible emergency situations during the door-to-door interviews was to Calm and triage families and offer reassurance and instruction on safety. The public health personnel had to deal with multiple problems both during the initial period and after the immediate danger had past. Actions taken by the community health nurse to help the people who were interviewed cope with the situations after the flooding were: to advise them to stay at shelter where there is electricity and food to contact Environmental health specialists for toxic waste To contact Social services to address immediate needs and resources. To arrange for instruction on safe use of generators in English and Spanish. To make arrangement for medications to be delivered the next day. Techniques that were used or could have been used to calm the fears of the people interviewed are to use short and concise statements. Perform active listening and confirm statements by repeating it back to the person being spoken with, use confrontation avoidance, and De-escalation. The other nursing personnel could be prepared to help in responding to a similar emergency with a much larger affected area (e.g., the effect of Hurricane Katrina). Through the development of a well-organized disaster response plan. Public health staff requires National Incident Management System (NIMS) training. Emergency preparedness training should be performed at least every six months. There needs to be a method of communication in case power lines, towers and electricity are not available; have a backup system in place and know where they are located (e.g. include, walkie talkies, Morse code and emailing). Community nurses should have car stock that includes protective gear (PPE) such as N-95 mask, barriers for CPR, gloves, biohazard containers and isolation gowns. Knowledge of the basic steps that are needed to take to ensure patient safety, such as safe evacuation, and early notification will help prevent unnecessary casualties during emergencies (Agency for Healthcare Research and Quality. www.ahrq.gov/prep. Accessed July 21, 2006. References Centers for Public Health Education and Outreach. (n.d.). Retrieved from https://cpheo1.sph.umn.edu/fcs/index.asp Health Care: Public Health Emergency Preparedness. (n.d.). Retrieved from http://www.ahrq.gov/prep

hemophilia Essay -- essays research papers

Hemophilia is a genetic bleeding disorder. People who have hemophilia have a deficiency or an absence of a coagulation protein. A blood clotting factor is deficient or absent. Bleeding is most often into joints, such as the knee, elbow, or ankle, but bleeding can occur anywhere in the body. People with hemophilia bleed longer, not faster. The severity of hemophilia varies greatly. Hemophilia A and Hemophilia B are the most common genetic bleeding disorders. Hemophilia A is observed in 80 percent of hemophiliacs and is a deficiency or absence of Factor VIII. It can also be referred to as "classic" hemophilia. In the second most common, hemophilia B, factor IX is missing. This is also known as the "Christmas Disease" because of the surname of the first patient studied. Hemophilia was identified as early as biblical times. Doctors in medieval times were familiar with it as well. In 1803, a Philadelphia doctor published the first description of hemophilia in the United States. But it was not until 30 years later that hemophilia became widely recognized. Hemophilia later developed a reputation as the "royal disease" because it passed from Queen Victoria of England to her descendants throughout the royal houses of Europe. About eighty percent of all cases of hemophilia have an identifiable family history of the disease; in other instances, it may be attributable to a spontaneous mutation. Researchers recently discovered that the spontaneous mutation of the factor VIII gene in two children was due to the attachment of a foreign "jumping gene" that disrupted the blood-clotting ability of the factor VIII gene. Inheritance is controlled by a recessive sex-linked factor carried by the mother on the X chromosome. A probability of one in two exists that each boy born to a normal male and a carrier female will be hemophiliac and the same chance that each girl of this union will be a carrier. Of the children of a hemophiliac male and a normal female, all the girls will be carriers and all the boys will be normal. Males cannot transmit the disability, and female carriers are free of the disease. Conventional wisdom suggests that 1 in 10,000 males in the United States have hemophilia. However, increased research and focus, on bleeding disorders in general and on bleeding disorders in women specifically, suggest a shift in what... ...h factor VIII replacement therapy is best for them. Inhibitors are proteins called antibodies that are made by our immune system to defend us from harmful disease. When our immune system identifies a foreign substance, it makes antibodies that will specifically recognize that substance and destroy it. In some individuals with severe hemophilia, the factor VIII replacement therapy is identified as a foreign substance by their immune system. If this happens, their immune system will make antibodies against factor VIII. These antibodies will inhibit the ability of the factor to work in the clotting process. The higher the antibody or inhibitor level, the more factor VIII replacement therapy it takes to overcome the inhibition and produce clotting. This can complicate the treatment of a bleed. The good news is that there are different types of therapies available to successfully treat most individuals who develop inhibitors. Work Cited Louis Levine, B.S., M.S.Ed., A.M., Ph.D. Professor, Department of Biology, City College of New York. "Hemophilia," Microsoft ® Encarta ® Online Encyclopedia 2000 http://encarta.msn.com  © 1997-2000 Microsoft Corporation. All rights reserved.

Case study on kerry group Essay

Introduction As part of my business management assignment I have been asked to investigate and evaluate the internal and external environment of an organization and the impact of change on an organization I intend on outlining the purpose, mission, vision , objectives and structure of this organization, explain the relevance of the type of structure. Do a pest and swot analysis and evaluate the impact of change on the organization , I will be completing this assignment with the aid of the website , Kerryfoodgroup.com the internet and my class notes. Aims The aims of this assignment are to ensue I cover the following aspects: Relevant information appropriately presented  Understanding and knowledge of chosen topic clearly demonstrated Present relevant data and statistics that support my work  Comprehensive evaluation of topic clearly demonstrated  Conclusions and recommendations bibliography Organisation types I am going to explore the following organisation types: Sole Trader Private limited Company Public limited Company Co-Operative Sole trader A sole trader is a type of business entity that allows one person to be solely responsible for the financial dealings of the business. The benefits and disadvantages of being a sole trader Advantages You are your own boss . Set your own working hours. Pick your rate of pay. Easy to set up. This form of business ownership has fewer regulations than other systems of ownership do. And another major benefit of operating as a sole trader is the ability to exert full control over the business Disadvantages Unlimited liability No sick pay. All pressure and responsibility is on you. No one o cover you if something happens Income tax 20-41% No one to share decision’s Suffer all losses Private Limited Company Private limited companies are viewed as corporations under the law and share several common characteristics with all corporations. However, private corporations are owned and operated by a small group of people. Because of their structure, private limited corporations operate under a set of limitations not imposed on public corporations. Advantages A private limited company is run by a small group, Many of them members of a single family, that wishes to limit the influence of outsiders on its company. Because private limited companies are run by a small group, they are usually not subject to takeovers and other challenges faced by public companies. The minmum required to set one upis 1 person and the max is 99. Disadvantages Profit Sharing Taxes Lack of privacy, information concerning the company is made public. Public limited company A company whose shares are traded on a stock exchange and can be bought and sold by anyone. Public companies are strictly regulated, and are required by law to publish their complete and true financial position so that investors can determine the true worth of its stock . Also called a plc Facebook is a reality formed plc . Advantages There is limited liability for the shareholders. The business has separate legal entity. There is continuity even if any of the shareholders die. These businesses can raise large capital sum as there is no limit to the number of shareholders. The shares of the business are freely transferable providing more liquidity to its shareholders . Disadvantages There are lot of legal bits and pieces required for forming a public limited company. It is costly and time consuming. In order to protect the interest of the ordinary investor there are strict controls and regulations to comply. These companies have to publish their accounts. The original owners may lose control. Public Limited companies are huge in size and may face management problems such as slow decision making and industrial relations problems. Co-Operative  A co-operative is a group of people acting together to meet the common needs and aspirations of its members e.g the Credit union, sharing ownership and making decisions democratically. Co-operatives are not about making big profits for shareholders, but creating value for customers this is what gives co operatives a unique character, and influences our values and principles. Advantages It is usually inexpensive to register a cooperative. All members and shareholders must be active in the cooperative. Shareholders have an equal vote at general meetings regardless of their shareholding or involvement in the cooperative. Members, other than directors, can be under  18, though these members cannot stand for office and do not have the right to vote. Shareholders, directors, managers and employees have no responsibility for debts of the cooperative unless those debts are caused recklessly, negligently or fraudulently. A cooperative is owned and controlled by its members, rather than its investors. Disadvantages There must be a minimum of five members. There is a usually a limited distribution of surplus (profits) to members/shareholders and some cooperatives may prohibit the distribution of any surplus to members/shareholders. Even though some shareholders may have a greater involvement or investment than others, they still only get one vote. Active and direct involvement of members/shareholders in the cooperative. These bullet points and definitions where all found in my class notes and I also used www.cro.ie Kerry Foods Group The company I am going to focus on will be Kerry foods group the history of the organisation traces the evolution and growth of Kerry Group from its modest beginnings in the south west of Ireland some 30 years ago into a successful, publicly traded, multinational corporation and leading player in the global food industry. Having commenced operation from a green field site in Listowel, Co. Kerry in 1972, the Kerry organisation has realised sustained profitable growth with current annualised sales of approximately â‚ ¬5.8 billion, Kerry Group today is a world leader in food ingredients and flavours serving the food and beverage industry, and a leading supplier of added value brands and customer branded foods to the Irish and UK markets. Kerry has grown to become one of the largest and most technologically advanced manufacturers of ingredients and flavours in the world. Spanning all major food categories, Kerry’s core technologies and global resources in culinary, dairy, lipid, meat, cereal, sweet and beverage systems and flavours provide innovative, practical product solutions to food manufacturers and food service companies. Purpose Kerry Foods operates in Ireland and the UK. they market there own brands across a wide range of categories and supply supermarket private labels in selected areas. they also have become one of the leading chilled foods companies in the geography through: A strong portfolio of brands, in which they continue to invest and grow Close working relationships with retail customers to develop mutually successful, private label business An unrivalled national service to the independent convenience sector, in both the UK and Ireland Mission statement Kerry Group will be: – the world leader in food ingredients and flavours serving the food and beverage industry, and – a leading supplier of added value brands and customer branded foods to the Irish and UK markets Through the skills and wholehearted commitment of ther employees, we will be leaders in our selected markets – excelling in product quality, technical and marketing creativity and service to our customers We are committed to the highest standards of business and ethical behavior, to fulfilling our responsibilities to the communities which we serve and to the creation of long-term value for all stakeholders on a socially and environmentally sustainable basis. Vision Group Goals & Long Term Targets †¢ Group revenue: +2% to +4% (LFL) volume growth †¢ Margin: 10% Group margin in 5 years †¢ Adjusted EPS* 10%+ †¢ ROAE* 15%+ and CFROI 12%+ Objectives Kerry’s Sustainability Programme represents a journey of continuous improvement – an ongoing process and strategy to secure sustainable growth. Sustainability is at the heart of our business strategy and enshrined in our corporate mission statement.As a world leader in ingredients & flavors and as a major consumer foods organization in Europe, Kerry aims to conduct its business in a responsible and sustainable manner. This demands a holistic approach to Group activities involving close liaison with our customers, suppliers, regulatory authorities, employees and other relevant stakeholders.Our Kerry Group Sustainability Council appraises, directs and provides leadership in promoting industry best practice sustainability program throughout the Group. Its membership includes Directors of Group functions with responsibility for all pillars of Kerry’s Sustainability Programme. Structure of the organization Business structure The Group is divided into several divisions: â€Å"Kerry Ingredients & Flavours† is the largest division producing over 15,000 ingredients, flavours and integrated solutions from more than 125 manufacturing sites worldwide. It claims to have become the largest and most technologically advanced provider of technology-based ingredients, flavours and integrated systems. â€Å"Kerry Foods† supplies added-value branded and customer branded food products to supermarket chains, convenience stores and independent retailers across the UK and Ireland. It has 15 manufacturing facilities all in Ireland and the UK. Products include sausage, sliced bacon, sliced meats, pastry products, ready meals, ready-to-cook products, savoury snacks, cheese, cheese snacks, dairy spreads, low-fat spreads, UHT products, home-baking products, salads, sandwiches and fruit juices. Consumer branded products include – in Ireland: Denny, Galtee, LowLow, Dairygold, Cheestrings, Charleville Cheese, Shaws, Coleraine, Golden Cow, EasiSingles, Dawn, Roscrea, Kerrymaid, Golden Olive, Mitchelstown, Calvita, Ballyfree, Move over Butter and Freshways – in the UK: Richmond, Wall’s,  Mattessons, LowLow, Cheestrings, Pure, Mr. Brain’s, Porkinsons, Bowyers, Lawsons, Green’s and Homepride. â€Å"Kerry Agribusiness† is headquartered in Charleville, Co. Cork, and works with the Group’s 4,000 milk suppliers in Ireland, to produce milk and related dairy products. Why have structures? Because it allows each sector to oranise itself. All businesses have to know what to do A clear structure makes it easier to understand the organisations objectives Organization chart What is a organisation chart? Companies use the organizational chart to pictorially depict their prevailing hierarchies, work flow and authority-responsibility diagrams. Small companies use flat organizational charts and large companies use tall organizational charts. Function The main purpose in drawing an organizational chart is to visually represent employee structures of the organization. One glance at the chart tells the viewer of all reporting to a particular employee and to whom he is answerable for work-related matters. Features A tall organizational chart is one that is shaped like a pyramid. There are several layers and tiers of employees. This structure is narrow and the top and broad at the bottom. A flat organizational chart is wide and expansive all throughout. More often than not, the employees report directly to the top management. This is pictorially depicted by a flat organizational chart. Considerations The type of organizational chart that the company draws must be based on the type of trade it is into. It is not practical and feasible for large  companies to have a flat organizational structure and chart. Large companies tend to centralize authority and departmentalize their strategic functions. Likewise, when small companies use the tall organizational structure and chart, they have to deal with greater bureaucracy and middlemen’s salaries. Is Kerry food group a flat or tall organisation? Swot Analysis of Kerry Group Kerry Group, Plc. Category Food Processing Sector Food and Beverages Tagline/ Slogan Brands that deliver USP Its worldwide facilities and unrivalled technical support network guarantees that its highly acclaimed ingredient systems and technologies are available to food processor or foodservice companies in all markets. STP Segment Business segments: Ingredients incorporating Culinary, Flavours and Bio-Science, Consumer Foods, Agribusiness and Dairies Target Group Agribusiness: Food sector, Animal feed sector, Drinks sector Consumer Foods & Dairies Consumers of branded & private labeled food products Positioning Committed to evolving food and developing brands that deliver, time and time again SWOT Analysis Strength 1. Established global processing and technical network with an ingredients portfolio extending to some nine thousand products to food processor and foodservice markets in over 120 different countries 2. Core technological strengths in savory ingredients, sweet ingredients, food coating systems, nutritional systems and specialty protein applications 3. An unrivalled national service to the independent convenience sector, in both the UK and Ireland 4. Close working relationships with retail customers to develop mutually successful, private label business 5. One of the leading consumer brands in Ireland and Europe Weakness 1.Input cost volatility due to raw material pricing being impacted by adverse crop production conditions 2. Limited market share and Pressure from competitive markets 3.Ingredients and Flavours market is highly fragmented Opportunity 1.Growth in demand for convenient ‘ready-to-use’ foods to match modern lifestyles and for fresh natural food products 2.Growing Ingredients and Flavours market 3. Tapping global capability via emerging markets & global customers Threats 1.Food industry supply and demand issues 2.Commodity cost inflationary momentum 3.Impact of foreign exchange fluctuations Competition Competitors 1.Associated British Foods Plc. 2.Greencore Group Plc. 3. Westbury Dairies Limited Pest analysis

Design of a global network using wimax - Free Essay Example

Sample details Pages: 31 Words: 9192 Downloads: 6 Date added: 2017/06/26 Category Statistics Essay Did you like this example? Introduction Previous Work Previous work that is closely related to this project involves experience with similar software simulation tool to the one that is used for the completion of the practical part of the project. OPNET simulator was used for the set up of a small network and its division into subnets. The project was completed as a lab assignment in the City University laboratories. It was divided into two main lab sessions each of them explained as follows. The aim of first lab session was to demonstrate the need for implementation of switches in the design of the local area networks. Two 16-station LANs were designed, using a hub for the first one; two hubs and a switch for the second one. The main task of the second laboratory was to demonstrate the basics of designing a network, taking into consideration the users, services location of hosts. Don’t waste time! Our writers will create an original "Design of a global network using wimax" essay for you Create order Using OPNET software, the concepts of networking were easily implemented and tested against the criteria set for satisfactory performance of the network model. The visual representation of the obtained results was used for a detailed analysis of the complexity of the network and its services provided to the users. 1 Technical Overview of the WiMAX Standard 1.1 Spectrum of the Standard The IEEE 802.16 standard is initially designed to provide a flexible, cost-effective, standards-based last-mile broadband connectivity to fill in the broadband coverage gaps that are not currently served by the wired solutions such as DSL. The advanced versions of the standard are aiming to create new forms of broadband services both with high speed and mobility. The IEEE 802.16 standard envisages the use of a wide range of frequencies from 2 to 66 GHz. However, the WiMAX Forum has focused on the use of 2 to 10GHz as the operating frequencies. A graphical representation of the WiMAX spectrum bands is listed below. It includes a comparison with other wireless standards; as well as indication of the regions using the listed bands. WiMAX is a technology that supports the delivery of last-mile wireless broadband access as an alternative to cable and DSL. WiMAX provides fixed, nomadic, portable and ultimately mobile wireless broadband connectivity without the need for line-of-sight with a base station. The design of a WiMAX network is based on the following major principles: Spectrum: to be deployed in both licensed and unlicensed spectra. Topology: supports different RAN topologies. Interworking: autonomous RAN architecture that enables faultless incorporation and interworking with Wi-Fi, 3GPP and 3GPP2 networks and existing IP core networks (e.g. DSL, cable, 3G) using IP-based interfaces. IP connectivity: supports a mix of IPv4 and IPv6 network interconnects. Mobility management: opportunity to expand the fixed access to mobility and broadband multimedia services delivery. WiMAX has defined two MAC classification profiles -the ATM and the IP. They have also defined two primary PHY system profiles: 25 MHz-wide channel (in the US) in the 10-66 GHz range. 28 MHz-wide channel (in Europe) in the 10-66 GHz range. IEEE 802.16 standard is designed to develop as a set of air interfaces standards for WMAN based on a universal MAC protocol but using the physical layer specifications, which one dependent on the range of use and the related regulations. The IEEE 802.16 working group designed a flexible MAC layer and associated physical layer for 10-66 GHz. It is more important to recognize certain factors that make some frequencies more suitable for use in WiMAX systems, both fixed and mobile [1new]. 1.1.1 Path Loss The first important factor is the operating frequency and path loss, which may arise from three basic factors: Free space path loss (FSL) It is defined by using the following formula (Equation 1): FSL=10log(4DFC)2 (1) D=distance from transmitter; F=frequency; C=speed of light. The path losses increase with the square of the frequency. For example, the path loss at 2 GHz frequency band is about 12 dB higher than the band at 0.5 GHz. This effect may be compensated with the antenna size. The increase in FSL with the square of the frequency requires the cell sizes at higher frequencies to be smaller in order to maintain link margins. High frequencies such as 5.8 GHz and above are best suited for line of sight environment. In NLOS conditions, a link at 5.8 GHz would support NLOS customer premises equipment at distances less than a kilometre. Loss due to NLOS operations In urban environments, WiMAX systems operate in a NLOS manner, there is a loss in received signals which depends on the reflected signal strengths. Frequencies above 10 GHz are treated separately. In general, lower frequencies such as 800-2000 MHz have better performance for NLOS than the higher bands. Due to the reception of waves reflected from many objects, the signal strength in most NLOS conditions varies sharply. Ground propagation models are required for path loss analysis and as a result additional margin needs to be given for the loss expected. Hence, multiple antenna techniques with spatial diversity are used to improve the margins in NLOS conditions. Loss caused by in-building penetration This kind of loss depends largely on the type of wall and whether the indoor location has windows. They are not very frequency dependent, at least in the zone of consideration of 2 GHz to 4 GHz. In buildings, losses can vary from 2 dB for a room with windows; to 6 dB for a brick wall. An increase up to 10-12 dB can be expected if the indoor areas were built using metal materials. 1.1.2 Doppler Shift and Coherence Time The second important factor is the Doppler Shift. It is an essential consideration for systems meant for mobile use. In the case of mobile WiMAX systems, which are meant to cater to vehicular speeds of up to 120 km/h, the effects of the Doppler shift are only relevant to the higher frequencies. It is given by the following formula (Equation 2): Ds=(VFC)cos (2) Ds=Doppler shift; V=velocity of user; F=frequency; C=speed of light and =angle between the incoming signal and direction of motion. Frequency shifts need to be less than 10% of the subcarrier spacing in order to maintain correct timing between different mobile stations, which may be operating with a base station. Table 1 represents the relationships between Doppler shift with operating frequency and speed. Frequency (MHz) Doppler shift (Hz) Coherence time (ms) Symbol duration (ms) 800 88.9 11.3 0.2 1600 177.8 5.6 0.2 2400 266.7 3.8 0.2 3400 377.8 2.6 0.2 5800 644.4 1.6 0.2 10000 1111.1 0.9 0.2 Table 1. Coherence time in ms is relevant to time synchronisation of mobile stations with the base station (times are in milliseconds) WiMAX is a multicarrier transmission system based on OFDM. The uplinks in WiMAX (both FDD and TDD systems) operate in a TDMA mode. Each subscriber station is assigned its own time slot and the transmission must take place within the slot. Other devices have the right to transmit in the other slots as allotted in the frame of WiMAX. In other words, the coherence of timing between different devices is important, which must operate in synchronisation. The coherence time is defined as 1Ds and it is inversely proportional to the Doppler shift. An indicator of how the motion is affecting the connection between symbols from different devices, a comparison of coherence time and the symbol time in OFDM. Hence, rather than considering a shift in the centre frequency, which is more likely for single-carrier systems, it is more suitable to consider the same shift in time in the subcarriers. Reducing subcarrier spacing would have adversely affected the Doppler spread, whereas increasing the subcarrier spacing would have reduced the delay spread and consequently intersymbol interference and the data rate. 1.2 Architecture In addition to the standard spectrum analysis and factors that are important for the appropriate selection of correct frequencies, the next part of the report presents the ideas of WiMAX network architecture and specifications. 1.2.1 Backhaul Solutions In telecommunications, thebackhaulportion of the network comprises the intermediate links between thecore networks, orbackbone, of the network and the small sub networks at the edge of the entire hierarchical network. Based on principle explained above, one of the architecture models is based on fixed IEEE 802.16 equipment. Independent of the used version, the technology can be employed in a fixed infrastructure as shown in Fig. 2. In this setting, the deployment of point-to-point connections can span tens of kilometres. WiMAX backhauling is defined by the infrastructure between the WiMAX ASN-GW and the base stations. [2 new] The control of the wireless network towards the client devices, as well as the transport traffic to the operator CSN is aggregated by the base stations. Fig. 3 is another example of how the system may be structured. A critical achievement factor in the deployment of the WiMAX systems is the numerous options the service provider can choose from. As the variety of options for the service providers were mentioned, there is time to focus on a topic much more related to the economic point of a network system. In particular, how the network will be develop in terms of cost and charges and they are agreed upon. A list of the important factors is presented as follows: Fixed costof providing a network infrastructure. Non-fixed cost of connection to the network- typically paid by the user in the form of connection cost. Cost of increasingthe networks capacity. Users who want to reschedule their transmission during peak times should not be charged for the growth of the networks capacity. Incremental cost of sending an extra packet. This cost should be very small or equal to zero without congestion, in view of the fact that the bandwidth of a broadband network is in general a shared resource. Social costdefined as the extra delay which occurs to other users by the transmission of data. Figure 4 shows the cost flow of a WiMAX network. WiMAXpoint to multipoint WiMAXmesh Clients WiMAX MS/RS or WiMAX mesh BS Clients WiMAX MS/RS or WiMAX mesh BS + Wi-Fi router WiMAXcell layout Cell dimensioning Number of WiMAX mesh BS in a cluster Wi-FiCell layout Number of AP in a single WiMAX cell Wi-Fi technology options Dual interface boards (WiMAX/Wi-Fi) Average subscribers per square mile Data traffic assumptions for Wi-Fi users and WiMAX SS/RS (utility/demand function) High QoS VoIP connections for Wi-Fi users and WiMAX SS Average number of data connections per square mile / month Backhaul capacity planning WiMAX BS to ISP WiMAX mesh to WiMAX main BS Wi-Fi routers to WiMAX BS Radio capacity planning Channel size Modulation type Frequency reuse FCC limitations Economic considerations CAPEX: WiMAX BS, Wi-Fi routers, spectrum costs, site preparation, site installation, backbone network equipment OPEX: Operation-administration-management costs, site Leases, equipment maintenance, customer acquisition Network revenue pricing model Time unit fees for Internet subscribers and VoIP subscribers (flat rate pricing) On-demand Service (user-based pricing) Charges: access, usage, congestion and QoS Fig. 4 Cost flow diagram for WiMAX networks 1.2.2 Mobile WiMAX Network Solution The second architecture model that is discussed is that of the mobile WiMAX. It is of great interest and use for the simulation project as it explains the principles behind the simulation that has been set. A WiMAX network consists of an ASN in the lowest level and network itself is in fact, quite intuitive. [1 new] An ASN is comprised of a number of BS connected to an access network, where the ASN is connected to the external networks using ASN-GW. The functions of the ASN are represented in Fig. 5 and include a number of BS, access networks, and access gateways. The functions are discussed in details as follows: Establishing of a connection with the MS, including PHY and MAC layer connectivity. Providing handover and roaming services for the MS within the ASN The user should be provided AAA facilities in conjunction with its home network; the ASN is capable of providing proxy AAA services Relay facilities between the ASN and the external networks should also be present Two functional entities are defined in ASN shown in Fig. 6: The base stationconnects to the MS using the WiMAX PHY air interface. The functions of the BS are to maintain the air interface with the MS, providing the DHCP proxy and to maintain its status idle or active. Fig. 6 is an illustration of a typical WiMAX BS. The uplink and downlink traffic scheduling as well as the QoS enforcement are provided by the BS, as the air interface is managed by the BS. The access service network gateway is the second functional entity. The ASN-GW is the point where traffic from all BS is aggregated for interface to external networks. Usually, the ASN-GW is physically a router. Functions such as QoS management, AAA functionalities are also part of the aggregation point responsibilities. ASN-GW may also have control functions over the BS. The alternative architecture embeds those control functions in the BS. Fig. 7 represents the typical ASN functions. If a comparison between WiMAX network architecture and a cellular network model such as GSM was to be done, similarities can easily be identified. The ASN-GW of the WiMAX network serves the functions that are provided by the SGSN; the access network is recognised as BSC in the GSM model, and the air interface is respectively the BST. Further reading and understanding of the GSM model architecture is recommended for the comparison between the two models. Generally, the WiMAX networks are defined to be much more open in building networks and they have greater level of functionalities in its network entities. Three distinct entities comprise a WiMAX network and its application environment: Network access provider entity that operates one or more ASNs. Typically, it is a WiMAX operator that operates ASN in one or more areas. Network service provider provides connectivity and services to NAPs. NSP needs only to connect to other NSPs and expect all services to be delivered through these connections; NSPs provide connectivity to NAPs via CSN. They are also responsible for providing mobility between their own nodes as well as nodes from other NSPs. Application service providers provide services such as HTTP, video streaming, file download, e-mail, etc. Fig. 8 introduces one more entity of the WiMAX network architecture the connectivity service network. The diagram shows that CSNs have AAA servers which are policy functions for QoS. They provide connectivity to external networks such as managed IP networks or the public internet. Policy functions for each device, user and service on the network as well as the security and authentication frameworks are provided by the AAA servers. Authentication at multiple levels is a key feature of the WiMAX network architecture. Additional key features of the mobile WiMAX network architecture include: Both the core and the radio access networks should be based on IP; protocols based on IEEE802.16 and IETF Open interfaces should be defined by fully-defined reference points Support of fixed network, nomadic, or mobile usage with full migration path to mobility A modular network architecture, which can grow based on usage requirements Integration into different types of IP and non-IP networks (for example: ATM, TDM, and others) Network core architecture is not based on support of any particular service, such as voice, data, or video; as a multi-service core network it supports QoS for each service and each connection QoS is based on both policy functions and enforcement The network architecture is relatively flat, which enables a WiMAX service to start with a single ASN; NWG has defined different ASN profiles for this purpose Inter-networking is supported with 3GPP, 3GPP2, Wi-Fi, or wired networks using IETF protocols. 2 WiMAX Layers After the spectrum and network analysis discussions, it is important to look deeper into WiMAX fundamentals. The following chapter has the aim to introduce the two main layers defined in the WiMAX standard, and to explain the related to them topics such as adaptive modulation, QoS, etc. As the WiMAX belongs to the IEEE 802 group, then the bridging or layer-2 concepts should be mentioned. [2] The addressing is based on MAC addresses and the base station is perceived as a bridge. In order to implement all layer 2 functionalities, the device used should be a bridge-not a router. For the identification for nodes addressing is used; as long as the node is recognized by the network, the address is replaced by use of circuits with circuit identifier. The WiMAX physical layer is based on orthogonal frequency division multiplexing. [2new] OFDM is a transmission scheme that enables high-speed data, video, and multimedia communications. It is used by numerous broadband systems DSL, Wi-Fi, DVB-H, MediaFLO and WiMAX. OFDM is an efficient scheme used for high data rate transmission in a non-line-of-sight or multipath radio environment. The MAC layer is based on connection-oriented principle and it is very similar to the ATM transport protocol, which connection uses a context that describes the mapping between the incoming flows and the underlying QoS. A station registers itself to the base station, negotiates the physical layer characteristics and then can communicate bidirectionally. A service flow defines the negotiated QoS for all matching packets (service-specific sub layer). The QoS can be changed dynamically and it supports extremely well data bursts. Everything is negotiated separately for uplink and downlink. 2.1 Physical Layer Details 2.1.1 OFDM Basics OFDM is a multicarrier modulation scheme that is based on the idea of dividing a given high-bit-rate data stream into several parallel lower bit-rate streams. Each of those streams is then modulated on separate carriers, the so called subcarriers or tones. Multicarrier modulation schemes eliminate or minimize ISI by making the symbol time large enough so that the channel induced delays are an insignificant proportion of the symbol duration. For that reason, in high-data-rate systems, in which the symbol duration is relatively small and it is inversely proportional to the data rate, splitting the data stream into many parallel streams increases the symbol duration of each stream. By doing so, the delay spread is only a small fraction of the symbol duration. OFDM is a spectrally efficient version of multicarrier modulation, in which the subscribers are selected in such way that they are orthogonal to one another over the symbol duration. In that way, it avoids the necessity to have no overlapping subcarrier channels to eliminate ISI. The first subcarrier has to have a frequency such that it has an integer number of cycles in a symbol period. The spacing between adjacent subcarriers (subscriber bandwidth Bsc) has to be defined by the following Equation 3: Bsc=BL (3) Where B is the nominal bandwidth, it is also equal to the data rate. L is the number of subcarriers. This relation ensures that all tones are orthogonal to one another over the symbol period. It can be shown that the OFDM signal is equivalent to the inverse discrete Fourier transform of the data sequence block taken L at a time. Therefore, it is very straightforward to implement OFDM transmitters and receivers in discrete time using IFFT and FFT, respectively. In order to completely eliminate the ISI, OFDM introduces guard intervals between the symbols. For the successful elimination, the guard interval should be larger than the expected multipath delay spread. On the other hand, the introduction of the guard interval implies power wastage and decrease in bandwidth efficiency. The amount of power waste depends on the proportion between the OFDM symbol duration and the guard time. Thus, the larger the symbol period, the smaller the power loss and bandwidth efficiency. Large symbol periods also mean more subcarriers. The size of the FFT in an OFDM design should be chosen carefully as a balance between protection against multipath, Doppler shift, and design cost/complexity. For a given bandwidth, selecting a large FFT size would reduce the subcarrier spacing and increase the symbol time. This is the reason why it makes it easier to protect against multipath delay spread. In contrary, the reduced subcarrier spacing makes the system more vulnerable to intercarrier interference owing to Doppler spread in mobile applications. Careful balancing is required to compete the influence of delay and Doppler spread. 2.1.2 Advantages and Disadvantages of OFDM There are several advantages of OFDM over other solutions for high-speed transmission. Reduced computational complexity: OFDM can be easily implemented using FFT/IFFT, where the processing requirements grow only slightly faster than linearly with data rate or bandwidth. The computational complexity of OFDM can be represented the following Equation 4. O(BlogBTm) (4) Where B is the bandwidth and Tm is the delay spread. This complexity is much lower than that of standard equalizer-based system, which complexity is shown by Equation 5: O(B2Tm) (5) Graceful degradation of performance under excess delay: the performance of an OFDM system degrades gracefully as the delay spread exceeds the value designed for. Greater coding and low constellation sizes can be used to provide fallback rates that are significantly more robust against delay spread. In other words, OFDM is well suited for adaptive modulation and coding, which allows the system to make the best of the available channel conditions. This is in contrast with the abrupt degradation owing to error propagation that single-carrier systems experience as the delay spread exceeds the value for which the equalizer is designed. Exploitation of frequency diversity : OFDM facilitates coding and interleaving across subcarriers in the frequency domain, which can provide robustness against burst errors caused by portions of the transmitted spectrum undergoing deep fades. WiMAX defines subcarrier permutations that allow systems to exploit this. Use as a multi-access scheme : OFDM can be used as multi-access scheme, where different tones are partitioned among multiple users. This scheme is also known as OFDMA and is exploited in mobile WiMAX. The ability to provide fine granularity in channel allocation is also offered by the OFDMA. In relatively slow time-varying channels, it is possible to significantly enhance the capacity by adapting the data rate per subscriber according to the SNR of that particular subcarrier. Robust against narrowband interference Suitable for coherent demodulation : it is relatively easy to do pilot-based channel estimation in OFDM system, which renders them suitable for coherent demodulation schemes that are more power efficient. Apart from the advantages that were already described, there are two main disadvantages: There is a problem associated with OFDM signals having a high peak-to-average ratio that causes nonlinearities and clipping distortion. This can lead to power inefficiencies that need to be countered. The second disadvantage is related to OFDM signals which are very susceptible to phase noise and frequency dispersion, and the design must mitigate these imperfections. This also makes it critical to have accurate frequency synchronization. 2.1.3 OFDMA: Sub channelization Sub channels are formed by the division of available subcarriers into groups. [3new] Fixed WiMAX based on the OFDM-PHY allows a limited form of sub channelization in the uplink only. There are 16 defined sub channels, where 1,2,4,8 or all sets can be assigned to a subscriber station in the uplink. Uplink sub channelization in fixed WiMAX allows SSs to transmit using only a fraction (as low as 1/16) of the bandwidth allocated to it by the BS. The scheme used allows link budget improvements and can be used to improve range performance and/or improve battery life of SSs. A typical 1/16 sub channelization factor provides a 12 dB link budget enhancement. In contrast, mobile WiMAX uses OFDMA-PHY and it allows sub channelization in both the uplink and downlink. Sub channels effectively form the minimum frequency resource-unit, which is allocated by the BS. Therefore, different users may be allocated different sub channels as this is multiple-access mechanism. It is also known as orthogonal frequency division multiple access, which gives mobile WiMAX PHY its name. Sub channels may be formed using wither contiguous subcarriers or subcarriers pseudo-randomly distributed across the frequency spectrum. More frequency diversity is achieved by using distributed sub carriers, which is particularly useful for mobile applications. WiMAX defines several sub channelization schemes based on distributed carriers for both the uplink and downlink. One of them is partial usage of subcarriers, which is mandatory for all mobile WiMAX implementations. The second sub channelization scheme is based on contiguous subcarriers and is also known as adaptive modulation and coding. Although the frequency diversity is lost, band AMC allows system designers to exploit multiuser diversity, allocating sub channels to users based on their frequency response. Multiuser diversity can provide significant gains in overall system capacity, if the system strives to provide each user with a sub channel that maximizes its received SINR. Generally, the contiguous sub channels are more suited for fixed and low-mobility applications. Fig. 9 shows a typical sub carrier structure. FIGURE 9 + explanation 2.1.4 Frame Structure Mobile WiMAX used to support Time Division Duplex only but recently full and half-duplex Frequency Division Duplex support has been added. [4 new] It is mainly because of local restrictions in some areas. A major disadvantage of the TDD is that it needs to be synchronised over the whole system. On the other hand, there are several reasons why TDD usage is preferred. One of them is that the ratio of DL/UL data rates can be adjusted freely. It is in contrast with the FDD where the ratio is always constant and in most cases symmetric. Channel reciprocity is assured by using TDD, which gives better support of link adaptation, MIMO and other closed loop advanced antenna technologies. Whereas FDD requires a pair channel, but TDD can share one for both DL/UL traffic. Additionally, from economical point of view, FDD transceivers are more complex and therefore more expensive to manufacture. For the simulation project that has been set up, FDD mode was used and for this purpose the next part of this chapter explains the FDD frame structure in relation to relaying. For information purposes TDD frame structure is also discussed. 2.1.4.1 Frame Format for FDD The FDD mode does not provide guard times and parallel transmissions in DL and UL. [5new] The BS always sets up the master frame, in other words, it generates the timing schedule for the next period. The process begins with synchronisation pilots, a broadcast channel and a random/contention access channel; a few regular frames follow, but this very much depends on the technology used. Some of the frames are reserved for the second hop(s) by the BS, which are later used in the responsibility of the relay(s). A term called stealth relaying is used when the BS does not even distinguish between relays and ordinary SSs. It is preferable to use centrally and relay-aware BS controlled resource allocation for further systems. Interleaved multihop frames are incorporated by modern multihop systems, where frames for the first and second hops alternate in time and they are all controlled by the BS. The smallest granularity resource unit is a chunk, 100 chunks form a basic frame. Symbols, on the other hand, are used for signalling and synchronization, but they are out of focus here. They are shown in grey in Fig. 10(a) and the only impact here is the overhead-resources not available for data throughput. DL and UL transmissions happen simultaneously in the same frame raster. There are 3 ways of integrating relaying (the frames used for the second hop or beyond: Time Domain Relaying: resources for hop1 and hop2 are separated in time (sequentially) Frequency Domain Relaying: recourses for hop1 and hop2 are separated in frequency (neighbour band) OFDMA Domain Relaying: recourses for hop1 and hop2 are separated in frequency (sub channels) As OFDMA was already introduces as topic earlier, it is important to describe what its advantages are over OFDM relaying. First one is that the resources can be subdivided in a finer granularity than it is possible using OFDM only. Fig. 10(b) shows that first-hop transmissions are always treated the same way. They only occupy the required resources for their traffic and there is not waste due to completely assigned but incompletely filled frames. In the UL several SSs share the full bandwidth and each of them transmits on a subset of sub channels, with a guard band between them. The BS or RN coordinates the orthogonal interference-free use of these sub channels by the SSs. OFDMA subdivision in the DL is also available, where the BS and RN send on distinct sub channels, but using sufficient guard band. Even if the side band power is below the signal level, this can cause serious interference trouble at the SS when receiving the useful signal from a far dist ant BS and the interference from the RN nearby. In this case, interference mitigation strategies in the BS are helpful. This also leads to proper association decisions for intra-cell handover. The handover concept is introduced later in the report and the fundamental principles are discussed in details. 2.1.4.2 TDD Frame Structure Mobile WiMAX TDD mode allows the DL and UL transmissions to share the same transmission medium. [6new] Fig. 11 shows the typical structure of TDD frame. Transmission and reception cannot occur simultaneously, due to the prohibitively complex filtering, which is essential for the separation of UL and DL. Something more, in order to avoid interference between the signals transmitted from the BS and other SSs, time gaps such as the transmit/receive transition gap or receive/transmit transition gap are needed. The TTG allows sufficient time for the BS to switch from transmit to receive mode. RTG provides time for the BS to switch from receiving to transmitting. Parameters that form the size of the time gaps are: cell radius, the transceiver turnaround time and other implementation constraints. 2.1.5 Adaptive Modulation and Coding in WiMAX It is inevitable to mention the modulation and coding techniques that are employed by the WiMAX standard. Their principles are important as later in the report; those modulations are used for the simulation purposes and are base on the discussion how the SSs can be connected to the BSs and what effect the modulation and coding have on the connectivity. WiMAX supports a variety of modulation and coding schemes. [3 new]This allows the scheme to change on a burst-by-burst basis per link, depending on channel conditions. The SS can provide feedback on the DL channel quality to the BS by using channel quality feedback indicator. For the UL, the BS can easily estimate the channel quality, based on the received signal quality. The BS scheduler can take into account the channel quality for each users UL and DL and assign a modulation and coding technique that maximizes the throughput for the available SNR. Adaptive modulation and coding increases the overall system capacity, as it allows real-time trade-off between throughput and robustness on each link. Table 2 lists various modulation and coding scheme used by WiMAX. In the DL, QPSK, 16 QAM, and 64 QAM are mandatory for both fixed and mobile WiMAX. 64 QAM is optional in the UL. FEC coding using conventional codes is mandatory as well. Conventional codes are combined with an outer Reed-Solomon code in the downlink for OFDM-PHY. Turbo codes and low-density parity check codes are optionally supported at a variety of code rates as well. There are 52 combinations of modulation and coding techniques that are defined in WiMAX as burst profiles. Downlink Uplink Modulation BPSK, QPSK, 16 QAM, 64 QAM; BPSK optional for OFDMA-PHY BPSK, QPSK, 16 QAM; 64 QAM optional Coding Mandatory: convolution codes at rate , 2/3, , 5/6 Mandatory: convolution codes at rate , 2/3, , 5/6 Optional: convolution turbo codes at rate , 2/3, , 5/6; repetition codes at rate ,1/3, 1/6, LDPC, RS-Codes for OFDM-PHY Optional: convolution turbo codes at rate 1/2., 2/3, , 5/6; repetition codes at rate , 1/3, 1/6, LDPC Table 2. Modulation and Coding supported by WiMAX. 2.2 MAC Layer Details The second important layer of the WiMAX standard is the MAC medium access control. In general, the 802.16 MAC is designed to support multipoint-to-multipoint architecture, where a centrally located BS handles multiple independent sectors simultaneously. [7 new] On the downlink, data to SSs are multiplexed in TDM fashion. On the contrary, the uplink is shared between SSs in TDMA fashion. IEEE standard 802.16 defines 2 general service-specific convergence sub-layers for mapping services to and from 802.16 MAC connections. The first one is the ATM convergence sub-layer, which is defined for ATM services. The second one is the packet convergence layer, defined for mapping packet services such as IPv4, IPv6, Ethernet, and virtual local area network. There are 3 primary tasks of the sub-layer: To classify service data units to the correct MAC connection Preserve or enable QoS Enable bandwidth allocation Depending on the type of service, the mapping takes a range of forms. Additionally to the basic convergence sub-layer tasks, the layers can also perform more complicated functions payload header suppression and reconstruction to enhance air link efficiency. As it was already mentioned, the 802.16 MAC is connection-oriented and all services, including inherently connectionless services, are mapped to a connection. Thus, it provides a mechanism for requesting bandwidth, associating QoS and traffic parameters, transporting and routing data to the appropriate convergence sub-layer; as well as all other actions associated with the contractual terms of service. Connections are referenced with 16-bit connection identifiers and may require continuously granted bandwidth or bandwidth on demand. Every SS has a standard 48-bit MAC address, which serves mainly as an equipment identifier. The primary addresses used during operation are the CIDs. Three management connections are assigned to the SS when entered the network. These connections reflect the three different management connections in each direction: Basic connection- used for the transfer of short, time-critical MAC and radio link control massages. Primary management connection- used to transfer short longer, more delay-tolerated messages (e.g. those used for authentication and connection setup). Secondary management connection- used for the transfer of standards-based management messages, such as DHCP, TFTP, and SNMP. Apart from the management connections, transport connections for the contracted services are also allocated to the SSs. Transport connections are unidirectional and facilitate different DL and UL QoS and traffic parameters; they are typically assigned to services in pairs. Additional connections for other purposes may also be reserved by MAC: Contention-based initial access Broadcast transmissions in the DL, as well as for signalling broadcast connection-based polling of SS bandwidth needs Multicast, rather than broadcast, connection-based polling. SSs may be instructed to join multicast polling groups associated with these multicast polling connections. 2.2.1 MAC PDU Construction and Transmission As it was already discussed, the MAC sub-layer is independent of the higher-layer protocol and performs such operations as scheduling, [3 new] ARQ, bandwidth allocations, modulation and code rate selection. The SDUs arriving from the higher-layer to the sub-layer are assembled to create the MAC PDU, which is the basic payload unit handled by the MAC and PHY layers. Multiple SDUs can be carried on a single MAC PDU, or a single SDU can be fragmented to be carried over multiple MAC PDUs; this is entirely based on the size of the payload. When an SDU is fragmented, the position of each fragment within the SDU is labelled by a sequence number. The usage of the sequence number is to ease assembling of the SDU from its fragments in the correct order at the receiver MAC layer. Multiple MAC PDUs destined to the same receiver can be concatenated and carried over a single transmission opportunity or data region. This is purely done to use the PHY resources more efficiently. This is shown in Fig. 12. For non-ARQ-enabled connections, each fragment of the SDU is transmitted in sequence. For ARQ-enabled connections, the SDU is first divided into fixed length ARQ blocks. Each ARQ block has its own block sequence number. ARQ BLOCK-SIZE parameter is used by the BS for each CID to specify the length of the block. The length of the SDU should be integral multiple of the ARQ BLOCK-SIZE, if it is not the last ARQ block is padded. Once the SDU is portioned into ARQ blocks, the partitioning remains until all the ARQ blocks have been received and acknowledged by the receiver. After the partitioning, the SDU is assembled into MAC PDUs in a normal fashion as it is shown in Fig. 12. For ARQ-enabled connections, the fragmentation and packing sub head er contains the BSN of the first ARQ block following the sub header. The ARQ feedback from the receiver comes in the form of ACK indicating successful reception of the ARQ blocks. The feedback is sent either as a stand-alone MAC PDU or piggybacked on the payload of a regular MAC PDU. ARQ feedback can be two types: Selective:indicates that the ARQ block has been received without errors Cumulative:indicates that all blocks with sequence number less than or equal to the BSN have been received without error. Each MAC PDU consists of a header followed by a payload and cyclic redundancy check. The CRC is based on IEEE 802.3 and is calculated on the entire MAC PDU; the header and the payload. Two types of PDUs (Fig. 13) are introduced, and each of them has different header structure: Generic PDU- used to carry data and MAC-layer signalling massages. It starts with a generic header, which structure is shown on Fig.13, and then followed by a payload and a CRC. The different information elements in the header of a generic MAC PDU are shown in Table 3. Bandwidth PDU- used by the SS to inform the BS that more bandwidth is needed in the UL, due to pending data transmission. This type of PDU consists of bandwidth-request header, and there is no payload or CRC. The header information elements are shown in Table 4. Field Length (bits) Description HT 1 Header type (set to 0 for such header) EC 1 Encryption control (0= payload not encrypted; 1= payload encrypted) Type 6 Type ESF 1 Extended sub header field (1 = ES present; 0 = ES not present) CI 1 CRC indicator (1 = CRC included; 0 = CRC not included) EKS 2 Encryption key sequence (index of the traffic encryption key and the initialization vector used to encrypt the payload) Rsv 1 Reserved LEN 11 Length of MAC PDU in bytes, including the header CID 16 Connection identifier on which the payload is to be sent HCS 8 Header check sequence Table 3, Generic MAC header fields Field Length (bits) Description HT 1 Header type (set to 1 for such header) EC 1 Encryption control (set to 0 for such header) Type 3 Type BR 19 bandwidth request (the number of bytes for uplink bandwidth request by the SS for the given CID) CID 16 Connection identifier HCS 8 Header check sequence Table 4. Bandwidth request MAC header fields Once a MAC PDU is constructed, it is handed over to the scheduler, which schedules the MAC PDU over the PHY resources available. The scheduler checks the service flow ID and the CID of the MAC PDU, which allows it to gauge its QoS requirements. Based on the QoS requirements of the MAC PDUs belonging to different CIDs and service flow Ids, the scheduler determines the optimum PHY resource allocation for all the MAC PDUs, on a frame-by-frame basis. 2.2.2 DL and UL MAP WiMAX MAC supports both TDD and FDD modes. [7 new] In FDD, both continuous and burst downlinks are supported. Continuous downlinks allow for certain robustness improvement techniques for example interleaving. Burst downlinks allow the use of more complex robustness and capacity enhancement techniques, e.g. subscriber level adaptive burst profiling and advanced antenna systems. The MAC builds the DL sub frame, starting with a frame control section. The frame control section contains the DL-MAP and UL-MAP messages. They indicate PHY transitions on the downlink; bandwidth allocations and burst profiles on the uplink. The DL-MAP is applicable to the current frame and is always at least 2 FEC blocks long. In both TDD and FDD modes, the UL-MAP provides allocations starting no later than the next downlink frame. If the processing times and the round trip delays are observed, then the UL-MAP may allocate starting in the current frame. The minimum time between receipt and applicability of the UL-Map for an FDD system is shown in Fig. 14 2.2.3 Authentication, Registration and Security Another important factor of the MAC protocol is that it manages procedures such as authentication, registration and security. Each of the SS holds two certificates: factory installed X.509 digital certificate and certificate of manufacturer. Those certificates are sent from the SS to the BS in the Authorization Request and Authentication Information messages. The certificates establish a link between the 48 bit MAC address of the SS and its public RSA key. The network is able to identify the SS using the certificates, and afterwards it can check the authorization of the SS. If the SS is authorized to join the network, BS will respond with an Authorization Reply containing an Authorization Key. The Authorization Key is encrypted with the SSs public key and used to secure further transactions. When the authorization is successful, the SS will be registered with the network. This will establish the secondary management connection of the SS and determine capabilities related to connection setup and MAC operation. The version of IP used on the secondary management connection is also determined during registration. WiMAXs privacy protocol is based on the Privacy Key Management protocol. It is based on the DOCSIS BPI+ specification, but has been modified to fit seamlessly into the MAC protocol. It accommodates stronger cryptographic methods, such as the Advanced Encryption Standard. PKM is build around the concept of security associations. SA is a set of cryptographic methods and the associated keying material. It contains the information about which algorithms to apply, which key to use, and so on. Every SS establishes at least one SA during initialization. Apart from the basic and primary management connections, all other connections are mapped to an SA either at connection setup time or dynamically during operation. For the traffic encryption, the PKM uses the Data Encryption Standard, running in the cipher block chaining more with 56-bit keys. The CBC initialization vector depends on the frame counter and differs from the frame to frame. To reduce the number of computationally intensive public key operations during normal operation, the transmission encryption keys are exchanged using 3DES with a key exchange key derived from the authorization key. The PKM protocol messages are authenticated using the Hashed Message Authentication Code protocol with SHA-1. Message authentication in essential MAC functions, such as the connection setup, is provided by the PKM protocol. 2.2.4 Services and Parameters The last part of the MAC layer is the services and their parameters. It is an essential part of the standard implementation and this part of the chapter lists all QoS that are provided by the WiMAX family. Scheduler is the one that controls the scheduling services for the standard and handles the mechanisms supported by the MAC to transport data. [9 new] Each connection is associated with a single data service. Data services are associated with a set of QoS parameters that define their behaviour. Two data parameters are used for the management of the parameters: dynamics service addition and dynamic service change. Five different services are supported: unsolicited grant services, real-time polling services, extended real-time polling services non-real-time polling services, and best effort. Table 5 lists the application and specification for each of those services. [10 new] QoS Category Applications QoS Specifications UGS VoIP Maximum sustained rate Maximum latency tolerance Jitter tolerance rtPS Streaming audio and video Minimum reserved rate Maximum sustained rate Maximum latency Traffic priority ertPS Voice with activity detection (VoIP) Minimum reserved rate Maximum sustained rate Maximum latency tolerance Jitter tolerance Traffic priority nrtPS File transfer protocol Minimum reserved rate Maximum sustained rate Traffic priority BE Data transfer, web browsing, etc. Maximum sustained rate Traffic priority Table 5. Mobile WiMAX applications and QoS UGS- supports real-time data streams. Each stream is of fixed-size data packets issued at periodic time intervals. It is particularly useful for applications such as VoIP without silence suspension. Mandatory service flow parameters are: maximum sustained rate, maximum latency tolerance, jitter tolerance and request/transmission policy. If the policy is present, the minimum reserved traffic rate parameter will be the same value as the maximum sustained traffic rate parameter. rtPS- supports real-time data streams, each of which is issued at periodic intervals. It is useful for MPEG videos and consists of variable-size data packets. Compulsory parameters are: minimum reserved rate, maximum sustained rate, maximum latency, traffic priority, and again request/traffic policy. ertPS- it is a combination of USG and rtPS. [4new] ertPS is designed to support VoIP with activity detection, which means that when there is a silence period in the communication, the bandwidth can be saved by downsizing the packets length. The maximum sustained traffic rate, which defines the default size of the allocations, may be changed with ertPS. nrtPS- used for delay-tolerant data streams, which consist of variable data packets. Minimum data rate is required as it used the FTP. Flow parameters are: minimum reserved rate, maximum sustained rate, traffic priority, and request/transmission policy. BE is used to support data streams for which no minimum service level is required and therefore may be handled on a space-available basis. Associated parameters are: maximum sustained rate, traffic priority, and request/transmission policy. 3 Handovers The aim of the next chapter is to introduce the term handovers and to explain their importance for the WiMAX standard features. Handovers are very vital part of a wireless technology.[11new] When an SS moves between different BSs, the connection should also move and in order to do so a seamless handover should be performed. By the term seamlessness, it defines the necessity to maintain current session, QoS and service level agreements during and after the handover. In other words, the seamless handover should not be noticeable by the user; however, this very much depends on the kind of services the user is requiring. With real-time applications, such as videoconferencing or streaming media, s slight decrease of the connection may be observed. In contrast, while a user is browsing a website or transfers files, they will most probably not notice any change in their connection. There are two crucial factors related to the handover procedure: the latency and the packet loss. They have to be as small as possible to make the handover seamless. Several reasons why and when a handover should be initiated are listed below: SS current position and velocity high velocity may lead to different handover decisions Link quality in case a BS is overloaded, the network can decide to relocate some of the SSs Conserving battery power for battery saving purposes, an SS may chose to switch to a closer station and be energy efficient Context and requirements if an SS requires different type of service, it may be necessary to change BS. Handovers have a significant effect on the performance of channel allocation algorithms. At high traffic loads, the majority of forced call terminations are as a result of the lack of channels available for handover rather than to interference. This is a major problem in microcellular systems, where the rate of handovers is considerably higher than that in normal cellular systems. There are a number of solutions to reduce the performance penalty caused by handovers. One of them is to reserve some channels solely for handovers, generally referred to as cut-off priority or guard channel schemes. However, this solution reduces the maximum amount of carried traffic or system capacity and hence yields increased new call blocking. Algorithms that give higher priority to requests for handovers than to new calls are called Handover prioritization schemes. Guard channel schemes are therefore a type of handover prioritization arrangement. Another type of handover prioritization is constituted by handover queuing schemes. Normally, when an allocation request for handoff is rejected, the call is forcibly terminated. By allowing handover allocation requests to be queued temporarily, the forced termination probability can be reduced. The simplest handover queuing schemes use a First-In First-Out (FIFO) queuing regime. A non-pre-emptive priority handover queuing scheme in which handover requests in the queue that are the most urgent ones are served first. A further alternative to help reduce the probability of handover failure is to allow allocation requests for new calls to be queued. New call allocation requests can be queued more readily than handovers because they are less sensitive to delay. Handover queuing reduces the forced termination probability owing to handover failures but increase the new call blocking probability. New call queuing reduces the new call blocking probability and also increases the carried teletraffic. This is because the new calls are not immediately blocked but queued, and in most cases they receive an allocation later. Handovers have a significant effect on the performance of channel allocation algorithms. At high traffic loads, the majority of forced call terminations are as a result of the lack of channels available for handover rather than to interference. This is a major problem in microcellular systems, where the rate of handovers is considerably higher than that in normal cellular systems. There are a number of solutions to reduce the performance penalty caused by handovers. One of them is to reserve some channels solely for handovers, generally referred to as cut-off priority or guard channel schemes. However, this solution reduces the maximum amount of carried traffic or system capacity and hence yields increased new call blocking. Algorithms that give higher priority to requests for handovers than to new calls are called Handover prioritization schemes. Guard channel schemes are therefore a type of handover prioritization arrangement. Another type of handover prioritization is constituted by handover queuing schemes. Normally, when an allocation request for handoff is rejected, the call is forcibly terminated. By allowing handover allocation requests to be queued temporarily, the forced termination probability can be reduced. The simplest handover queuing schemes use a First-In First-Out (FIFO) queuing regime. A non-pre-emptive priority handover queuing scheme in which handover requests in the queue that are the most urgent ones are served first. A further alternative to help reduce the probability of handover failure is to allow allocation requests for new calls to be queued. New call allocation requests can be queued more readily than handovers because they are less sensitive to delay. Handover queuing reduces the forced termination probability owing to handover failures but increase the new call blocking probability. New call queuing reduces the new call blocking probability and also increases the carried teletraffic. This is because the new calls are not immediately blocked but queued, and in most cases they receive an allocation later. There are two main types of handovers: horizontal (handovers within the same technology) and vertical (handovers between different network access technologies). Horizontal handovers- are Layer-2 handovers and are also referred to as micro-mobility. In this case only the BS is changed and the IP-information is kept the unchanged. This kind of handover causes small latency and low packet loss Vertical handovers- Layer-3 handovers and are also referred as macro-mobility. It changes the IP-connection point, and as a result the IP information is changed as well. As a result, significant latency and packet loss are observed. 3.1 Handover Types WiMAX specification supports three types of handovers: Hard Handover, Fast Base Station Switching, and Macro Diversity Handover.[4new] HHO is compulsory, whereas the other two are optional. The WiMAX forum has been working on the enhancement of the HHO techniques to achieve handovers in less than 50 milliseconds. 3.1.1 Hard Handover HHO is a procedure that changes the serving BS using a break-before-make approach. Effectively, this means that the connection to the old BS is broken before the new BS is connected to the SS. Using this approach, excess signalling traffic is avoided during the handover procedure, however, the time before the connection is again in normal operation may be longer. While the SS is connected to a BS, it listens to the link-layer messages for another BS, which periodically broadcasts neighbour advertisement messages. The advertising messages are used for network identification and recognition of the services that are provided. Facts about the signal quality from a neighbouring BS are included in the messages. In case a better BS is not found, the SS stores the information that has been received for future handovers. Fig. 15 illustrates a typical scenario of HHO, when a moving user reaches the point where the signal level is of better quality with another BS. A further decision criterion has to be set up to avoid constant handover back and forth between BSs. 3.1.2 Macro Diversity Handover When MDHO is supported by MS and by BS, the Diversity Set (or in some cases it is called Active Set) is maintained by SS and BS. Diversity set is a list of the BSs, which are involved in the handover procedure. Diversity set is defined for each of SSs in network. SS communicates with all BSs in the diversity set (Fig. 16). For downlink in MDHO, two or more BSs transmit data to SS such that diversity combining can be performed at the SS. For uplink in MDHO, MS transmission is received by multiple BSs where selection diversity of the received information is performed. The BS, which can receive communication among SSs and other BSs, but the level of signal strength is not sufficient is noted as Neighbour BS. While the SS is moving towards the neighbouring BS, at some moment the signal from the neighbouring BS becomes strong enough and the BS can be included in the active set. The factor that is used to measure the inclusion/exclusion of the BS is the long term CINR. There are two ways that the SS uses to monitor DL control information and broadcast messages: It listens only to the anchor BS for burst allocation information of other BSs in the active set Listens to all BSs in the active set. By listening to all active set BSs, a DL/UL-MAP message from any BS may include information for other BSs. The MDHO is started when the SS decides to receive/transmit from multiple BSs at the same time. For DL traffic, two or more BSs transmit the data to the SS, which performs diversity combining. For the UL traffic, the traffic generated by the SS is received by all BSs in the active set and selection diversity is then performed. Interestingly, the MDHO requires all BSs to communicate on synchronised basis, because of the frames sent by the BSs at a certain time frame have to be received by the SS within the specific prefix interval. The BSs frame structure have to be synchronised and the frequency assignments to have the same values. Furthermore, the same set of CIDs and MAC/PHY PDUs sent to the SS have to be generated by the BSs. The encryption information and network entry exchanged information have to be shared between the SS and the BSs as well. 3.1.3 Fast Base Station Switching In FBSS, the SS and BS diversity set is maintained similar as in MDHO. SS continuously monitors the base stations in the diversity set and defines an Anchor BS. Anchor BS is only one base station of the diversity set that MS communicates with for all uplink and downlink traffic including management messages (Fig. 17). This is the BS where SS is registered, synchronized, performs ranging and there is monitored downlink channel for control information. The anchor BS can be changed from frame to frame depending on BS selection method, which means each frame can be sent via different BS in diversity set. Generally, the requirements for the FBSS are the same as the ones of MDHO without the demand for the same CIDs and MAC/PHY PDUs.