Introduction to Computer Theory

CHAPTER 1 BACKGROUND The twentieth century has been filled with the most incredible shocks and surprises: the theory of relativity, Communist revolutions, psychoanalysis, nuclear war, television, moon walks, genetic engineering, and so on. As astounding as any of these is the advent of the computer and its development from a mere calculating device into what seems like a â€Å"thinking machine. † The birth of the computer was not wholly independent of the other events of this century.The history of the computer is a fascinating story; however, it is not the subject of this course. We are concerned with the Theory of Computers, which means that we form several abstract mathematical models that will describe with varying degrees of accuracy parts of computers and types of computers and similar machines. Our models will not be used to discuss the practical engineering details of the hardware of computers, but the more abstract questions of the frontiers of capability of these mec hanical devices.There are separate courses that deal with circuits and switching theory (computer logic) and with instruction sets and register arrangements (computer ar-chitecture) and with data structures and algorithms and operating systems and compiler design and artificial intelligence and so forth. All of these courses have a theoretical component, but they differ from our study in two basic ways. First, they deal only with computers that already exist; our models, on 3 4 AUTOMATA THEORY the other hand, will encompass all computers that do exist, will exist, and that can ever be dreamed of.Second, they are interested in how best to do things; we shall not be interested in optimality at all, but rather we shall be concerned with the question of possibility-what can and what cannot be done. We shall look at this from the perspective of what language structures the machines we describe can and cannot accept as input, and what possible meaning their output may have. This descripti on of our intent is extremely general and perhaps a little misleading, but the mathematically precise definition of our study can be understood only by those who already know the concepts introduced in this course.This is often a characteristic of scholarship—after years of study one can just begin to define the subject. We are now embarking on a typical example of such a journey. In our last chapter (Chapter 31) we shall finally be able to define a computer. The history of Computer Theory is also interesting. It was formed by fortunate coincidences, involving several seemingly unrelated branches of intellectual endeavor. A small series of contemporaneous discoveries, by very dissimilar people, separately motivated, flowed together to become our subject.Until we have established more of a foundation, we can only describe in general terms the different schools of thought that have melded into this field. The most obvious component of Computer Theory is the theory of mathematic al logic. As the twentieth century started, mathematics was facing a dilemma. Georg Cantor (1845-1918) had recently invented the Theory of Sets (unions, intersections, inclusion, cardinality, etc. ). But at the same time he had discovered some very uncomfortable paradoxes-he created things that looked like contradictions in what seemed to be rigorously proven mathematical theorems.Some of his unusual findings could be tolerated (such as that infinity comes in different sizes), but some could not (such as that some set is bigger than the universal set). This left a cloud over mathematics that needed to be resolved. David Hilbert (1862-1943) wanted all of mathematics put on the same sound footing as Euclidean Geometry, which is characterized by precise definitions, explicit axioms, and rigorous proofs. The format of a Euclidean proof is precisely specified. Every line is either an axiom, a previously proven theorem, or follows from the lines above it by one of a few simple rules of in ference.The mathematics that developed in the centuries since Euclid did not follow this standard of precision. Hilbert believed that if mathematics X'ere put back on the Euclidean standard the Cantor paradoxes would go away. He was actually concerned with two ambitious projects: first, to demonstrate that the new system was free of paradoxes; second, to find methods that would guarantee to enable humans to construct proofs of all the true statements in mathematics. Hilbert wanted something formulaic-a precise routine for producing results, like the directions in a cookbook.First draw all these lines, then write all these equations, then solve for all these points, and so on and so on and the proof is done-some approach that is certain and sure-fire without any reliance BACKGROUND 5 on unpredictable and undependable brilliant mathematical insight. We simply follow the rules and the answer must come. This type of complete, guaranteed, easy-to-follow set of instructions is called an a lgorithm. He hoped that algorithms or procedures could be developed to solve whole classes of mathematical problems.The collection of techniques called linear algebra provides just such an algorithm for solving all systems of linear equations. Hilbert wanted to develop algorithms for solving other mathematical problems, perhaps even an algorithm that could solve all mathematical problems of any kind in some finite number of steps. Before starting to look for such an algorithm, an exact notion of what is and what is not a mathematical statement had to be developed. After that, there was the problem of defining exactly what can and what cannot be a step in an algorithm.The words we have used: â€Å"procedure,† â€Å"formula,† â€Å"cookbook method,† â€Å"complete instructions,† are not part of mathematics and are no more meaningful than the word â€Å"algorithm† itself. Mathematical logicians, while trying to follow the suggestions of Hilbert and st raighten out the predicament left by Cantor, found that they were able to prove mathematically that some of the desired algorithms cannot exist-not only at this time, but they can never exist in the future, either. Their main I result was even more fantastic than that.Kurt Godel (1906-1978) not only showed that there was no algorithm that could guarantee to provide proofs for all the true statements in mathematics, but he proved that not all the true statements even have a proof to be found. G6del's Incompleteness Theorem implies that in a specific mathematical system either there are some true statements without any possible proof or else there are some false statements that can be â€Å"proven. † This earth-shaking result made the mess in the philosophy of mathematics even worse, but very exciting.If not every true statement has a proof, can we at least fulfill Hilbert's program by finding a proof-generating algorithm to provide proofs whenever they do exist? Logicians bega n to ask the question: Of what fundamental parts are all algorithms composed? The first general definition of an algorithm was proposed by Alonzo Church. Using his definition he and Stephen Cole Kleene and, independently, Emil Post were able to prove that there were problems that no algorithm could solve. While also solving this problem independently, Alan Mathison Turing (1912-1954) developed the concept of a theoretical â€Å"universal-algorithm machine. Studying what was possible and what was not possible for such a machine to do, he discovered that some tasks that we might have expected this abstract omnipotent machine to be able to perform are impossible, even for it. Turing's model for a universal-algorithm machine is directly connected to the invention of the computer. In fact, for completely different reasons (wartime code-breaking) Turing himself had an important part in the construction of the first computer, which he based on his work in abstract logic.On a wildly differ ent front, two researchers in neurophysiology, Warren 6 AUTOMATA THEORY Sturgis McCulloch and Walter Pitts (1923-1969), constructed a mathematical model for the way in which sensory receptor organs in animals behave. The model they constructed for a â€Å"neural net† was a theoretical machine of the same nature as the one Turing invented, but with certain limitations. Mathematical models of real and abstract machines took on more and more importance.Along with mathematical models for biological processes, models were introduced to study psychological, economic, and social situations. Again, entirely independent of these considerations, the invention of the vacuum tube and the subsequent developments in electronics enabled engineers to build fully automatic electronic calculators. These developments fulfilled the age-old dream of Blaise Pascal (1623-1662), Gottfried Wilhelm von Leibniz (1646-1716), and Charles Babbage (1792-1871), all of whom built mechanical calculating devic es as powerful as their respective technologies would allow.In the 1940s, gifted engineers began building the first generation of computers: the computer Colossus at Bletchley, England (Turing's decoder), the ABC machine built by John Atanosoff in Iowa, the Harvard Mark I built by Howard Aiken, and ENIAC built by John Presper Eckert, Jr. and John William Mauchly (1907-1980) at the University of Pennsylvania. Shortly after the invention of the vacuum tube, the incredible mathematician John von Neumann (1903-1957) developed the idea of a stored-program computer.The idea of storing the program inside the computer and allowing the computer to operate on (and modify) the program as well as the data was a tremendous advance. It may have been conceived decades earlier by Babbage and his co-worker Ada Augusta, Countess of Lovelace (1815-1853), but their technology was not adequate to explore this possibility. The ramifications of this idea, as pursued by von Neumann and Turing were quite pr ofound. The early calculators could perform only one predetermined set of tasks at a time.To make changes in their procedures, the calculators had to be physically rebuilt either by rewiring, resetting, or reconnecting various parts. Von Neumann permanently wired certain operations into the machine and then designed a central control section that, after reading input data, could select which operation to perform based on a program or algorithm encoded in the input and stored in the computer along with the raw data to be processed. In this way, the inputs determined which operations were to be performed on themselves.Interestingly, current technology has progressed to the point where the ability to manufacture dedicated chips cheaply and easily has made the prospect of rebuilding a computer for each program feasible again. However, by the last chapters of this book we will appreciate the significance of the difference between these two approaches. Von Neumann's goal was to convert th e electronic calculator into a reallife model of one of the logicians' ideal universal-algorithm machines, such as those Turing had described.Thus we have an unusual situation where the advanced theoretical work on the potential of the machine preceded the demonstration that the machine could really exist. The people who first discussed BACKGROUND 7 these machines only dreamed they might ever be built. Many were very surprised to find them actually working in their own lifetimes. Along with the concept of programming a computer came the question: What is the â€Å"best† language in which to write programs?Many languages were invented, owing their distinction to the differences in the specific machines they were to be used on and to the differences in the types of problems for which they were designed. However, as more languages emerged, it became clear that they had many elements in common. They seemed to share the same possibilities and limitations. This observation was at f irst only intuitive, although Turing had already worked on much the same problem but from a different angle. At the time that a general theory of computer languages was being developed, another surprise occurred.Modem linguists, some influenced by the prevalent trends in mathematical logic and some by the emerging theories of developmental psychology, had been investigating a very similar subject: What is language in general? How could primitive humans have developed language? How do people understand it? How do they learn it as children? What ideas can be expressed, and in what ways? How do people construct sentences from the ideas in their minds? Noam Chomsky created the subject of mathematical models for the description of languages to answer these questions.His theory grew to the point where it began to shed light on the study of computer languages. The languages humans invented to communicate with one another and the languages necessary for humans to communicate with machines s hared many basic properties. Although we do not know exactly how humans understand language, we do know how machines digest what they are told. Thus, the formulations of mathematical logic became useful to linguistics, a previously nonmathematical subject. Metaphorically, we could say that the computer then took on linguistic abilities.It became a word processor, a translator, and an interpreter of simple grammar, as well as a compiler of computer languages. The software invented to interpret programming languages was applied to human languages as well. One point that will be made clear in our studies is why computer languages are easy for a computer to understand whereas human languages are very difficult. Because of the many influences on its development the subject of this book goes by various names. It includes three major fundamental areas: the Theory of Automata, the Theory of Formal Languages, and the Theory of Turing Machines.This book is divided into three parts correspondi ng to these topics. Our subject is sometimes called Computation Theory rather than Computer Theory, since the items that are central to it are the types of tasks (algorithms or programs) that can be performed, not the mechanical nature of the physical computer itself. However, the name â€Å"computation† is also misleading, since it popularly connotes arithmetical operations that are only a fraction of what computers can do. The term â€Å"computation† is inaccurate when describing word AUTOMATA THEORY processing, sorting and searching and awkward in discussions of program verification. Just as the term â€Å"Number Theory† is not limited to a description of calligraphic displays of number systems but focuses on the question of which equations can be solved in integers, and the term â€Å"Graph Theory† does not include bar graphs, pie charts, and histograms, so too â€Å"Computer Theory† need not be limited to a description of physical machines but can focus on the question of which tasks are possible for which machines.We shall study different types of theoretical machines that are mathematical models for actual physical processes. By considering the possible inputs on which these machines can work, we can analyze their various strengths and weaknesses. We then arrive at what we may believe to be the most powerful machine possible. When we do, we shall be surprised to find tasks that even it cannot perform. This will be-our ultimate result, that no matter what machine we build, there will always be questions that are simple to state that it cannot answer.Along the way, we shall begin to understand the concept of computability, which is the foundation of further research in this field. This is our goal. Computer Theory extends further to such topics as complexity and verification, but these are beyond our intended scope. Even for the topics we do cover-Automata, Languages, Turing Machines-much more is known than we present he re. As intriguing and engaging as the field has proven so far, with any luck the most fascinating theorems are yet to be discovered.

Compare and Contrast Three Hostels in Sydney Essay

There are a lot of hostels in Sydney which are attracted because of its price and facilities. However, there are only three hostels that are suitable with postgraduate students, namely Maze Backpackers, Central Station Hotel and Nomads Westend Backpackers. This report will compare and contrast them with regard to location, price and facilities. Firstly, the location is contrasted between all these hostels. Central Station Hotel has the best location. It is near Central Station which is easily accessible by train, taxi and bus. While Maze Backpackers is in 417 Pitt Street and is located 5 minutes walking from this hostel to Central Station, Nomads Westend Backpackers is next to Central Station and its address is 412 Pitt Street. Secondly, the price is the most important feature is considered among three hostels and the price of rooms for each hostels is completely different. Central Station Hotel has only private rooms while Maze Backpackers and Nomads Westend Backpackers have shared rooms and private rooms. The cost of shared room with 4 beds in Maze Backpackers is $20. 58 whereas the cost of shared room whit 4 beds in Nomad Westend Backpackers is $23. 07 so it’s more expensive than Maze Backpackers’s. The private room in Central Station Hotel is the most expensive. It cost $38. 68 whereas a private room at Maze Backpackers and Nomads Westend Backpackers cost $17. 4 and $20. 94 respectively. Finally, there are some similarities and differences in their facilities. All of them have the Internet/Wifi, 24 hour reception; washing machines, safety deposit and credit card accepted but Maze Backpackers and Nomad Westend Backpackers are more convenient than Central Station Hotel because they have lounge area. However, Central Station is suitable with postgraduate students who need to use photocopying machines.

Discuss Briefly the Influence of Body Language, Voice Modulation, Audience Awareness and Presentation Plan for Successful Oral Presentation? Essay

— Eye contact, facial expressions, posture, movements, gestures.Why is it useful? It is natural and a part of communication. to clarify meaning; it is very visual to vent nervousness to maintain interest to emphasize The golden rule is â€Å"Be natural and relaxed!† | * Positive body language * eye contact to keep audiences’ attention (Asian audience might feel aggressed.) facial expressions should be natural and friendly: raise eyebrows to show surprise – open eyes wide – squint your eyes – curl your eyebrows * the hands Lots of possibilities to emphasise, to enumerate. to express sincerity or reflexion Be conscious of what you do with your hands If you are unhappy, hold notes or cards to occupy them arm – movements back and forth to suggest flow. Open arms to include or welcome ideas * body movement to indicate a change of focus keep audience’s attention move forward to emphasize move to side to indicate a transition gesture up and down head motions are movements to indicate importance or acknowledgement pen or pointer to indicate part, place (on a transparency) shrug shoulder to indicate I don’t know or care * posture stand straight but relaxed (do not slouch or lean sideways) Lean forward to emphasize however No hands in pockets Negative body language Failing to make eye contact Do not look at your notes all the time Looking at the screen/board means your back is turned to the audience cutting contact Don’t stare, or look blankly into people’s eyes Avoid swaying back and forth like a pendulum Avoid leaning against walls Be aware of your nervous tics Do not fold your arms like a barrier While one hand in a pocket gives a very relaxed pose, both hands in pockets looks too casual and should be avoided The Voice The voice is probably the most valuable tool of the presenter. It carries most of the content that the audience takes away. One of the oddities of speech is that we can easily tell others what is wrong with their voice, e.g. too fast, too high, too soft, etc., but we have trouble listening to and changing our own voices. There are five main terms used for defining vocal qualities (Grant-Williams, 2002): * Volume: How loud the sound is. The goal is to be heard without shouting. Good speakers lower their voice to draw the audience in, and raise it to make a point. * Tone: The characteristics of a sound. An airplane has a different sound than leaves being rustled by the wind. A voice that carries fear can frighten the audience, while a voice that carries laughter can get the audience to smile. * Pitch: How high or low a note is. Pee Wee Herman has a high voice, Barbara Walters has a moderate voice, while James Earl Jones has a low voice. * Pace: This is how long a sound lasts. Talking t oo fast causes the words and syllables to be short, while talking slowly lengthens them. Varying the pace helps to maintain the audience’s interest. * Color: Both projection and tone variance can be practiced by taking the line â€Å"This new policy is going to be exciting† and saying it first with surprise, then with irony, then with grief, and finally with anger. The key is to over-act. Remember Shakespeare’s words â€Å"All the world’s a stage† — presentations are the opening night on Broadway! There are two good methods for improving your voice: 1. Listen to it! Practice listening to your voice while at home, driving, walking, etc. Then when you are at work or with company, monitor your voice to see if you are using it how you want to. 2. To really listen to your voice, cup your right hand around your right ear and gently pull the ear forward. Next, cup your left hand around your mouth and direct the sound straight into your ear. This helps you to really hear your voice as others hear it†¦ and it might be completely different from the voice you thought it was! Now practice moderating your voice. Questioning Keep cool if a questioner disagrees with you. You are a professional! No matter how hard you try, not everyone in the world will agree with you! Although some people get a perverse pleasure from putting others on the spot, and some try to look good in front of the boss, most people ask questions from a genuine interest. Questions do not mean you did not explain the topic good enough, but that their interest is deeper than the average audience. Always allow time at the end of the presentation for questions. After inviting questions, do not rush ahead if no one asks a question. Pause for about 6 seconds to allow the audience to gather their thoughts. When a question is asked, repeat the question to ensure that everyone heard it (and that you heard it correctly). When answering, direct your remarks to the entire audience. That way, you keep everyone focused, not just the questioner. To reinforce your presentation, try to relate the question back to the main points. Make sure you listen to the question being asked. If you do not understand it, ask them to clarify. Pause to think about the question as the answer you give may be correct, but ignore the main issue. If you do not know the answer, be honest, do not waffle. Tell them you will get back to them†¦ and make sure you do! Answers that last 10 to 40 seconds work best. If they are too short, they seem abrupt; while longer answers appear too elaborate. Also, be sure to keep on track. Do not let off-the-wall questions sidetrack you into areas that are not relevant to the presentation. If someone takes issue with something you said, try to find a way to agree with part of their argument. For example, â€Å"Yes, I understand your position†¦Ã¢â‚¬  or â€Å"I’m glad you raised that point, but†¦Ã¢â‚¬  The idea is to praise their point and agree with them as audiences sometimes tend to think of â€Å"us verses you.† You do not want to risk alienating them. Preparing the Presentation After a concert, a fan rushed up to famed violinist Fritz Kreisler and gushed, â€Å"I’d give up my whole life to play as beautifully as you do.† Kreisler replied, â€Å"I did.† To fail to prepare is to prepare to fail The first step of a great presentations is preplanning. Preparing for a presentation basically follows the same guidelines as a meeting (a helpful guide on preparing and conducting a meeting, such as acquiring a room, informing participants, etc.) The second step is to prepare the presentation. A good presentation starts out with introductions and may include an icebreaker such as a story, interesting statement or fact, or an activity to get the group warmed up. The introduction also needs an objective, that is, the purpose or goal of the presentation. This not only tells you what you will talk about, but it also informs the audience of the purpose of the presentation. Next, comes the body of the presentation. Do NOT write it out word for word. All you want is an outline. By jotting down the main points on a set of index cards, you not only have your outline, but also a memory jogger for the actual presentation. To prepare the presentation, ask yourself the following: * What is the p urpose of the presentation? * Who will be attending? * What does the audience already know about the subject? * What is the audience’s attitude towards me (e.g. hostile, friendly)? A 45 minutes talk should have no more than about seven main points. This may not seem like very many, but if you are to leave the audience with a clear picture of what you have said, you cannot expect them to remember much more than that. There are several options for structuring the presentation: * Timeline: Arranged in sequential order. * Climax: The main points are delivered in order of increasing importance. * Problem/Solution: A problem is presented, a solution is suggested, and benefits are then given. * Classification: The important items are the major points. * Simple to complex: Ideas are listed from the simplest to the most complex. Can also be done in reverse order. You want to include some visual information that will help the audience understand your presentation. Develop charts, graphs, slides, handouts, etc. After the body, comes the closing. This is where you ask for questions, provide a wrap-up (summary), and thank the participants for attending. Notice that you told them what they are about to hear (the objective), told them (the body), and told them what they heard (the wrap up). And finally, the important part — practice, practice, practice. The main purpose of creating an outline is to develop a coherent plan of what you want to talk about. You should know your presentation so well, that du ring the actual presentation, you should only have to briefly glance at your notes to ensure you are staying on track. This will also help you with your nerves by giving you the confidence that you can do it. Your practice session should include a live session by practicing in front of coworkers, family, or friends. They can be valuable at providing feedback and it gives you a chance to practice controlling your nerves. Another great feedback technique is to make a video or audio tape of your presentation and review it critically with a colleague.

Case Study Research Paper Example | Topics and Well Written Essays - 2500 words

Case Study - Research Paper Example County, Western Walsh County, Grand Forks, Pembina, Cass County and Williams among the counties and areas that have already received flood warnings from National Weather Service in 2010 (NWS Report, 2010). Indeed, the â€Å"heavy winter snowstorms in 1997 led to massive spring flooding along the Red River thereby resulting in migration and displacement of more than ten per cent (10%) citizens† in North Dakota. This not only hampered the economic growth because of a sudden seize in business activities but also disrupted the society at large. It is worthwhile to mention that the financial burden had to be absorbed by US government, which initiated the move to ensure settlement of internally displaced persons (IDPs) in North Dakota with the assistance of International welfare agencies, Non-governmental and Inter governmental organizations. Some of the examples of flood related agencies include Red Cross, The Salvation Army, FEMA, North Dakota Department of Emergency Services, National Weather Service and others etc (Edward, 2000). It must be highlighted that North Dakota has already observed severe storms and flooding in March 2009 followed by recent flooding in March and April 2010 that in turn have increased vulnerability of residents of this state. In fact, residents of affected counties and areas are left with no other option but to migrate to safer places. This paper is an attempt to highlight the impact of natural disasters specifically on Cass County of North Dakota state. The paper will then throw light over the argument that vulnerability seems to be decreasing in Cass County because the experts have measured risk of only 1.4 out 10 in this particular area. In addition, the paper will also discuss any possible economic effects of flooding on Cass County and draw conclusions after analyzing the latest available information and facts. Finally, the paper will end up with a prediction about Cass County’s vulnerability and its future that will be supported by

The Emancipation proclamation Essay Example | Topics and Well Written Essays - 1000 words

The Emancipation proclamation - Essay Example The declaration settled the state’s aspect towards complete abolition of slavery. Although Lincoln, the President of the United States, gave the directives to release all the African American slaves, it was only the beginning of the end of slavery. Slavery was taking place in all states, in the United States before the declaration. America by the dates of the Emancipation Proclamation was approaching its third year in the civil war. The declaration of freedom to all African American slaves had an instant and weighty effect on the progress of the war. The proclamation by President Lincoln had been carefully anticipated because he had proposed the idea to his cabinet several months before its announcement. The emancipation of Proclamation was a declaration to free all African American slaves, but it was unsuccessful, it was only the beginning of the end of slavery. The declaration saved the Union since freeing the slaves, then became a certified war target because it gathered passionate responses from both the South and the North. The proclamation led to the ending of the civil war that was taking place. As a result of the proclamation, African Americans were allowed to join the Union’s armed forces that saw almost 200,000 African Americans joining to uprightly serve in the armed forces by the end of the civil war. As time progressed, the Whites put the African Americans through other forms of slavery. This is because the Emancipation Proclamation had been limited in several ways. The declaration only applied to the states that had withdrawn from the Union, leaving slavery intact and untouched in those states that were loyal. It also deliberately excused parts of the Union, which had come to be controlled by the North. The proclamation had been made, but it was so sad when it was realized that its validity depended on the military trium ph of the Union (NA & RA 2014). The Emancipation Proclamation might not have ended the African

Today, organisations need no longer concern themselves with service Essay

Today, organisations need no longer concern themselves with service quality, satisfaction and customer loyalty value is now the key to corporate success - Essay Example Among the many reasons why I agree with the above statement is that value has become a core function in Business Corporation to the extent that it has been relative to the overall organizational endeavour and success in its commercial activities. In essence, values are those principles that govern the existence, purpose and overall activities of an organization. Therefore, every organization is governed by certain principles that constitute its value (Cahill, 2006, 34). Value is a broad concept that underscores the inherent essence of an organization or in simple terms value underscores the organizational personality and moral fibre. As a result, value is of great importance in determining the efficacy of a corporation and has often been described as the key to organizational success in modern times. The evolution of organizations has witnessed a radical change in the priorities that govern organizational success. For instance, there was a time when quality was the core function of o rganizations and the success of Business Corporations was hinged on the capacity to deliver quality goods and services. During this time, most organizations primarily focused on quality parameters of their products and ignored the other considerations. Previously, the marketing concept defined organizational success as a function of marketing whereby an organization was successful only if it properly marketed its goods and services appropriately. The marketing concept was a quick replacement of the product concept that insisted on quality. In essence, the marketing concept implied that quality was not as important as marketing since customers buy goods on the basis of being persuaded and not on the basis of quality (Hurth, 2006, 8). The customer satisfaction concept, on the other hand, lays emphasis on the satisfaction of customers needs, fantasies and desires as the primary determinant of organizational success. This premise is based on the assumption that

Management of risk falls among the elderly Essay

Management of risk falls among the elderly - Essay Example The need to address the issue of falls among the elderly is therefore an important consideration. This paper shall discuss the management of risk falls among the elderly, specifically carrying out a critical analysis of the main theoretical and clinical concepts/principles and relevance to clinical care. Following a balanced and evidenced critique, this paper will develop recommendations for clinical practice and/or educational development of nursing practitioners in relation to the topic. Search strategy An initial internet search was carried out via Google Scholar using the following search words and specific combinations: falls elderly; fall risk elderly; management falls elderly; impact falls elderly. Literature dated from 2001 onwards was further evaluated for inclusion into this study. A search of the following databases was also carried out: Cochrane, Medline, and PubMed using the same search words specified above. The inclusion criteria covered elderly patients 65 years and a bove, with or without history of falls, with or without history of mental health illness including dementia, with or without history of osteoarthritis or other diseases affecting mobility, gait, or balance, with or without history of stroke rendering paralysis, and those undertaking any form or medication which may cause dizziness or disorientation. The following inclusion criteria are possible contributory elements to falls among the elderly and any of these elements present may also pose equal risk to the elderly patient. The credibility of the authors, including publication, and peer-review of the chosen literature was evaluated. Chosen studies were then specifically assessed in terms of relevance. Contextual information Falls as incidents caused by the aging process are often associated with diseases like Parkinson’s disease, musculoskeletal issues, cognitive degradation, and impairment of sensory systems (Carter, et.al., 2002). Incidents of falls often increase as people get older and as the elderly continue to advance in age. It is also one of the major causes of morbidity and mortality among the elderly (Rubenstein and Josephson, 2006). Morbidity from falls includes major injuries and fractures, limited mobility, as well as functional health decline and permanent disability (Wolf, et.al., 2003). A common effect of falls is hip fracture and some of these falls often lead to fractures, especially among the older adults (Moreland, et.al., 2004). These falls are considered preventable and much interest has been directed to these methods of prevention, especially in relation to the risk factors which exacerbate these risks (Barnett, et.al., 2003). Various studies have been carried out evaluating these fall risks and preventive measures for these falls. Most of these studies indicate that the risk for falls increase with the advancing age of individuals, with higher risks seen among those in the over 60 age range (Li, et.al., 2005). Studies also reveal that fall risks are often associated with different factors including history of past falls, cognitive impairment, impairment in the performance of activities of daily living, weakness of muscles or bones in the lower extremities due to disability, impaired gait or balance, dizziness, arthritis, history of stroke, poor eyesight, low body mass index, use of psychotropic medications causing dizziness or disorientation (American Geriatrics Society, et.al., 2001). A

Film Close Analysis Essay Example | Topics and Well Written Essays - 1250 words

Film Close Analysis - Essay Example The next clip is also edited. 4 seconds Camera closeup of Douzi’s mother, Douzi is standing in the frame too but his image is blurred. His mother refuses to raise him at the brothel. She is crying and making sniffing sounds. Then she smiles and tried to cajole him. 5 seconds Long-shot of all three characters, Douzi’s mother sits down on her knees. Guan is seated far right of the frame across the table. He rises so his back is to the camera and asks her to leave. 2 seconds. Camera takes a close-up of Douzi and his mother. There is a loud clicking sound of the sharpening blades in the background. She covers his face with a scarf. Douzi tells her he can’t feel his hands they are so cold. 4 seconds Camera shows a medium shot of Douzi bent on a bench with this mother on the opposite side holding a knife. There is a loud clicking sound of a butcher’s knife. Douzi shivers several times and then removes the scarf. He looks at his decapitated hand. 5 seconds Medium shot of doors bursting open as Douzi’s mother rushes in carrying him. She has blood on her face, both are screaming and crying as she carries him. The camera stays focus on them as they move across the school. Other students rush after her. 3 seconds Next is a clip from the same room where they were holding a meeting with Guan. Douzi has escaped his mother’s grasp and is hiding under the table. He runs when she tries to reach for him. The camera shows a long shot of Douzi jumping across stairs and running into the veranda of the school. Other boys follow him. Boys try to grab him as Douzi runs. The finally catch him. Loud music plays. In this scene the character Douzi is introduced in the film, previously he was a by-stander to a street performance. From this point forward Douzi’s take up the main role in the film. In this scene, Xiao Douzi is taken to an Opera school by his mother. The teacher Master Guan spots his superfluous finger and refuses to admit him as his student. His

Technical report Research Paper Example | Topics and Well Written Essays - 1250 words

Technical report - Research Paper Example The human dependence on electricity has been increasing dramatically at a huge rate. The amount of electricity, which we depend on every day, is unlikely to go down in the coming years rather its demand is expected to increase. The period of the industrial revolution provided several technologies that required burning fossil fuels for them to work properly. In modern world, most of the energy used in powering all the equipment emanate from fossil fuel combustion. Fossil fuel energy is derived from oil, natural gas, and coal. These fuels are combusted to produce energy in the form of electricity for use. The burning of fossil fuels does have detrimental effects on the environment. Once burned, they release greenhouse gasses and other air pollutants into the atmosphere. Eventually, the continuous use of fossil fuels will eventually deplete its supply throughout the world. On the other hand, the use of renewable sources is a good alternative but its energy supply cannot meet the demand of the growing population and usage. In the interest of preserving the natural environment and consequently maintaining the fossil fuel supply globally, alternative methods of energy must be looked at. These alternatives must provide adequate electricity to meet the demand and minimize the damage to the natural environment. Despite the negative image of the nuclear energy as a source of electricity, the use of nuclear energy may be the most efficient and realistic source of meeting the ever-increasing demand for power globally. In today’s world, global warming is a major issue that affects several people, economies, animals and the entire society. Over the past years, Global warming has been rising because of the increase in its major contribution such as industrialization, fossil fuel burning, increase in greenhouse gasses and increasing population (Nuclear Energy Institute, 2009, September). For several years, arguments and debates have been raging on how to

Sacking a contractor Essay Example | Topics and Well Written Essays - 1000 words

Sacking a contractor - Essay Example This essay is aimed at discussing comprehensively the stipulated procedures for undertaking dismissal of a contractor or a supplier under the following conditions, in the event that the contractor’s work is defective, where the contractors work is causing delay and in incidences where the contractor is working in a dangerous manner. Guidelines presented in this discussions will be based on the New Engineering Contract (NEC) provisions of the United Kingdom. The termination table under the NEC contract provisions details the procedure for the termination of a contract by the employer. The table provides that the employer may dismiss a contract given that the contractor has substantially failed to comply with the written obligations of the contract. Thus, defective working by the contractor could be categorized under this clause. However, NEC provides a framework for prior correction of defective processes and activities as a measure of mitigation to prevent termination of the contract. Under the clause for tests and inspections, it is expected that upon provisions of materials and samples by both the employer and the contractor for inspection, that the supervisor and the contractor notify each other of the inspection result. The contractor should correct any occurrence of defective work and the inspection should be repeated after correction of the defects. The test and inspection clause stipulates that the contractor should correct the identified defects within the defect correction period. Subsequently, the supervisor should issue a defect certificate latest on the defects date and towards the end of defect correction period. These provisions should prevent the onset of contract termination process due to substandard work by the contractor. If the contractor’s work is still defective, the employer may dismiss the contractor. However, the

The Role of the Advanced Practice Nurse Essay Example | Topics and Well Written Essays - 1250 words

The Role of the Advanced Practice Nurse - Essay Example The complexity of the contemporary healthcare environment has significantly changed and the role of nurses has also continued to change due to increased technology advancement. The access to healthcare delivery and nurses offering these services are changing rapidly due to increased demanding needs; therefore, each state is attempting to deal with these increasing healthcare changes through expanding and advancing the roles of nurses. Educators are now required to offer effective training services to graduates in order to prepare them with clear understanding of the Advanced Practice Nurse (APN) roles. APN refers as the nursing interventions that influence healthcare outcomes such as care management, nursing administration, direct clinical care of individual patients and development of healthcare policies. Understanding APN roles, professional and regulatory issues will enable nurses to make reasonable transition in the healthcare market. Educators should employ effective approaches for building APN role content into graduate course units since this can enable nurses to their intended goals effectively. Therefore, the purpose of this paper is to offer clear analysis of the roles being played by advanced practice nurses in the contemporary healthcare market. Core APN competencies The core competencies for APN nursing roles arise from role requirements, nursing regulations, nursing principles and practices, as well as, professional behavior standards necessary to offer competent, ethical and safe care. These core competencies offer the basis through which practitioners, human resource managers and educators can determine the acceptance level necessary for practicing in APN role in a certain situational context. The core competences address two significant elements including the professional development and the clinical practice both of which are significant for the APN role to attain the acceptable nursing standards and practices. a) Clinical Practice Competencies Practice core competencies are among the significant APN roles and this includes participating in direct patient care. This is an essential part of clinical practice because it adequately fulfills the role of nursing practitioner. Hamric and Hanson (2003) argue that direct clinical practice is one of the central competencies for APN because it informs and offers a foundation for which to build pillars for expert coaching. It also provides a basis for collaboration, research and ethical decision making vital for meeting the demanding needs of patients. Scholars have attempted to examine critical roles played by APN and the way these roles have tremendously changed in the contemporary healthcare market (Hamric and Hanson, 2003). Th e authors also attempts to offer clear and comprehensive roles of APN nurses in the contemporary society. Nurses employ applicable counseling, interpersonal skills and valuable communication skills; thus they initiate therapeutic relationships. They also work in collaboration with other healthcare professions and employ effective ethical standards in order to meet the demanding needs of their clients. b) Professional Development Competencies The professional development competencies are also significant APN roles because they help individuals to accomplish and maintain the level of proficiencies necessary to practice. They focus on the role of individuals in self governance of their occupation practice and personal development. According to Hamric and Hanson (2003), professional role development takes into considerations the theoretical principles and norms within the specialty practice area for nursing graduates. The content in professional role development should offer the graduat e with clear understandings of nursing profession, regulations, necessary requirements for nurses and APN roles (Hamric and Hanso

Education in Pakistan Essay Example for Free

Education in Pakistan Essay President Asif Ali Zardari signed ‘The Right to Free and Compulsory Education Bill 2012’ into law. The bill, which sought to ensure all children between five to 1 6 years of age are provided free education. He urged provincial governments to promulgate similar legislations in their respective assemblies as well. He said the responsibility for providing free education rests with both federal and provincial governments, referring to article 25-A of the Constitution. The article 25-A of Constitution of Pakistan obligates the state to provide free and compulsory quality education to children of the age group 5 to 16 years. The federal government will now provide free textbooks and uniform s to children and ensure schools have qualified teachers. Free pre-school education, early childhood care and free medical and dental inspection will also be provided to all citizens and no child will be subjected to corporal punishment â€Å"Under the law, private schools will be required to provide free education to disadvantaged students, who will comprise 10% of each class,† Zardari said, adding that school management committees will be established to persuade parents into sending their children to schools. â€Å"We will honor our international commitments and achieve the targets set by the Education for All and Millennium Development Goals initiatives. National Educational Policy 2009 Under the 18th constitutional amendment control and management of the education sector has been devolved to the provinces. They are now responsible for the key areas of the education sector i.e. curriculum and syllabus, centers of excellence, standards of education up to intermediate level (Grade 12) and Islamic education. Planning and policy and standards of education beyond Grade 12 are covered under Federal Legislative List. All the provinces have shown their commitment to the National Education Policy 2009. The National Educational Policy (NEP) 2009 is a milestone which aims to address a number of issues including: * Quality and quantity in schools and college education * Universal primary education * Improved Early Children Education (ECE) * Improved facilities in primary schools * Converting primary schools to elementary schools * Detaching classes XI-XII from college education * Adopting a comprehensive definition of ‘free ‘education * Achieving regional and gender parity especially at elementary level the share of resources for education in both public and private sectors Accordingto the latest Pakistan Social and Living StandardsMeasurement (PSLM) Survey 2010-11, the literacyrate for the population (10 years and above) is 58percent during 2010-11,

Project Design of Portable Stand for Tablet Computer

Project Design of Portable Stand for Tablet Computer 1.1 Customer Specification We were approached by a leading computer brand to design a small, lightweight and portable stand that can be used for any of the companys tablet computers. The company had a strong emphasis on the product being portable and the ability to fit into the end users pocket. The product should allow the end user to easily watch movies, read eBooks, surf the web, conduct a presentation, view photos and much more. The company would be looking to retail this product at  £11.99 and each unit should cost no more than  £4 to manufacture. They have also given us 12 months to complete the design with a prototype to be viewed in month 9. 1.2 Design Specification After considering the customers specification we began to brainstorm to generate possible solutions. First of all the product is to be small and lightweight which makes the material to be used one of the most important factors. Due to the low production price the stand will be made from ABS plastic resin which can be injection moulded. The stand will consist of 5 injection moulded parts which are connected by screw pivot barrels. The bottom of the tablet will feature a non-skid cushioned pad which will allow the stand to be used almost anywhere. Width (Folded)2.5 cm Length (Folded)17.8 cm Height (Folded)2.5 cm Weight 85g No of moulded parts5 1.3 Safety Considerations The first point of action is to identify all safety and non-safety critical engineering safety considerations, Customer safety requirements and design safety requirements. For doing this there are many techniques that will be used: Risk Assessment Identify hazards Observe what actually happens and identify hazards that can reasonably be expected to be present. Attention will be taken to any significant hazards which could cause serious harm or affect a number of people. Employees will be asked for their views as they may be aware of hazards which are not immediately obvious. Who can be harmed? Everyone should be taken into consideration during the risk assessment, including individuals who may not be present at all times. Evaluate risk- This will assess the likelihood that harm from a particular hazard may happen whilst also taking into consideration the precautions already in place. Record findings- Significant findings must be recorded by writing them down. Details of how the assessment was made will be unnecessary. Written documents should be kept for future reference as they may help to demonstrate that legal obligations have been met. Review and arise- The whole process will be reviewed and new processes or procedures introduced can then lead to new hazards which would result in the need for a new review of all assessments to be carried out to keep them up to date. Failure Mode and Effects Analysis FMEA This analytical technique explores the effects of failures or malfunctions of individual components in a system. This will be the first step of a reliability study. This will involve reviewing all the components and assembly of the stand to identify failure modes and their causes and effects. If any part of the stand fails what will be the result? The development of the design and testing of the product should ensure that failures have been eliminated or the risk has been reduced to an acceptable level. Advantages: Improve the quality, reliability and safety of the product Improve company image and competitiveness Increase user satisfaction Reduce system development time and cost Reduce the potential for warranty concerns Early identification and elimination of potential failure modes Increases teamwork and idea exchange Reduce the possibility of same kind of failure in future Fault Tree Analysis This is a graphical technique that will provide a systematic description of the combinations of possible occurrences in a system. This can result in an undesirable outcome. This analysis method will be used to understand how things can fail and to identify the best way to reduce the risk of these happening. Fault tree analysis will be used to: Understand the logic leading to the undesired state Show compliance with safety/reliability requirements Prioritize the contributors leading to the undesired state/event Monitor and control the safety performance Minimise and optimise resources Assist in the design of the product Function as a diagnostic tool Event Tree Analysis This will allow us to see what pathway is creating the greatest probability of failure. This is based on binary logic where an event has or has not happened. It is valuable in analysing the consequences arising from a failure or undesired event. The event tree will begin with an initiating event. The consequences of this event are followed through a series of possible paths where each path will be assigned a probability of occurrences allowing them to be calculated. Advantages: Enables the assessment of multiple faults and failures No need to anticipate end events Areas of single point failure, system vulnerability may be identified and assessed Allows resources to be deployed properly Work can be computerized Visual cause and effect relationship Relatively easy to learn and execute Follows easy to see fault paths Combines hardware, software, environment, and human interaction Permits probability assessment Commercial software is available 1.4 Project Schedule Month à ¯Ã†â€™Ã‚  Event à ¯Ã†â€™Ã‚ ¢ Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Problem Identified Initial research Develop Product Build Prototype Testing Redesign Communicate and conclude Problem Identified The customer provided us with their specification required for the proposed new product.Initial research After Looking over the customer specification research will be conducted to see what products already exist. A brainstorming session will then take place to come up with potential solutions including pro and con lists. From these a best product will then be selected to go ahead and produce.Develop Product Once the best possible product has been identified the key requirements for each feature is selected. This will then give and idea of materials needed and how they will construct the tablet. This will then allow costs to be calculated.Build Prototype First of all the prototype will be created using CAD software in two and three dimensions. This prototype created in CAD will have all dimensions with tolerances and finishes. This will then be passed onto the production team to construct. This will also be shown to the customer at this stage to ensure it meets exp ectation.Testing Once the prototype arrives it must be tested and evaluated to determine if it works and meets the original customer specification. Minor adjustments may be needed at this point to finalise the design.Redesign Using the information gathered during testing, evaluation of the design the solution can then be optimised and revised to achieve better results.Communicate and conclude The final product will be shown to the customer before mass production will follow depending on the feedback from the customer. 2.1 Manufacturing considerations. The prototype was originally modelled using 3d CAD software from where this design was then passed on to the production team to create a solid model of the stand. The prototype did function in the correct manner but the weight was a slight issue. With the product being designed to be portable the weight would need to be reduced. It was decided that the solid components would be hollowed and supports would be set between each side of a component to strengthen them. The total cost for production has been set not to exceed  £4 per unit. The intention is for the stand to be mass produced to decrease product cost and increase profit margin. Due to the small nature of each individual part the best possible way of constructing these will be to use the injection moulding process. Injection moulding is one of the leading methods of producing plastic components. This is a fast process which is used to produce a large number of identical items. After considering many different materials it was established that ABS plastic resin met all the characteristics needed to form each component whilst also being cheaper than many of the other materials available. The companys current injection moulding machine will be used for making the 5 plastic resin components. A 3d model of this is shown below: The clamping end with moving platen takes half of the mould tool. This opens and closes the mould and supplies sufficient force to keep the mould closed when molten ABS resin is injected under pressure. The injection unit takes plastic raw plastic resin granules, heats them until molten, and injects them into the mould. The rotating screw forces the plastic along the barrel. When the right amount of material for the next shot has accumulated the screw stops rotating. The screw then acts like a plunger moving forward and forcing the molten plastic into the mould tool. Materials There were many different materials that could be used for making the individual parts but after much consideration it was decided that ABS plastic resin pellets would be used. ABS is a thermoplastic resin commonly used for injection moulding applications. ABS (Acrylonitrile Butadiene Styrene) possesses medium strength and performance at a low cost. It is available in multiple grades, colours, and Izod impact ratings. ABS Features Benefits: Easily machined Tough Low cost Rigid High impact strength Ideal for moulding Good chemical and stress cracking resistance Excellent abrasion resistance; electrical properties, moisture and creep resistance. Availability At the moment ABS pellets can be purchased from Zibo City Linzi Yixiang Chemical Co. Ltd. In China and shipped to the UK for  £1000 per Metric Ton which is 1000000grams. Each rotational part will be held together by 5g pivot barrels also shipped from Asia costing  £0.20p per unit. With each fully built unit weighing in around 85grams and requiring 3 pivot barrels each unit would cost: 1000000/70=14286 units  £1000/14286= 0.6p per unit in ABS material ABS material + 3 pivot barrels =  £0.66p per unit material cost. This price does not include cost of production. 2.2 Simulation/Modelling The design process will utilize the use of CAD to produce the trailers drafting and design. By using CAD this will allow the quality of the design to be improved whilst also speeding up the design process. The drafted design of the trailer will be used by any professional involved in the construction of the trailer. 3d simulation also allows for real life situations to be tested prior to the build. Advantages and disadvantages of using CAD Advantages Can be more accurate than hand-drawn designs which reduce human error. You can save and edit ideas, which make it easier and cheaper to modify your design as you go along. You can modify existing ideas, which saves time. Disadvantages The software itself can be expensive so initial costs are high. Staff need to be trained how to use the software, which also adds to costs. Requires a PC. Safety Considerations Although the product is fairly small and compact there are still many safety issues that need to be taken into consideration. Legislation should also be adhered to. Plastic materials are generally inert and lend themselves to product safety. The safety of plastic materials and products which will be used by users and consumers is extremely important to the company and to the industry as a whole. The cost problems associated with exercises such as product recalls and product failure could have a negative image on the company. The risk assessment technique used for tablet stand was a Fault Modes and Effects Analysis (FMEA). This method will explore the effect of malfunctions and failures for the individual parts of the product whilst also looking at what can happen within the working environment. The essential questions which are asked in regards to the working environment are: What are the hazards? Who could be harmed and how? What are the effects? What is currently done? Can anything else be done? What are the hazards? Who can be harmed and how? Whats being done? What can be done? Slips and trips Staff/contractors may be injured if they trip over objects or slip on spillages. à ¢-   Procedures for oil spillages in place and are adhered to à ¢-   Floors are in good condition à ¢-   Staff wear safety shoes à ¢-   Good lighting throughout No further action required Use of injection machinery Staff/contractors may suffer serious injury from unguarded moving parts of machinery à ¢-   All dangerous parts of machinery guarded to manufacturers standards à ¢-   All new machinery checked before first use à ¢-   Machinery guards are properly maintained and inspected No further action required Workplace transport Staff may suffer serious, fatal, injuries if struck by a vehicle or fork lift truck. à ¢-  Good segregation measures are on site, à ¢-   All staff, including contractors, wear hi-visibility work wear à ¢-   Annual safety inspections Provide safety rules before jobs begin Manual handling Staff may suffer back pain from handling heavy/bulky objects. à ¢-  Staff are trained in safe manual handling à ¢-   Safe system of work agreed à ¢-   Manual handling aids are No further action required Fire Staff could have fatal injuries from smoke inhalation or burns. à ¢-  Fire risk assessment had been previously done, and any necessary action taken, à ¢-   Staff and contractors told of fire and evacuation policy No further action required Noise Staff may suffer discomfort and potential hearing damage if working in noisy areas or using noisy equipment. à ¢-   If possible, jobs in production areas done when the injection moulding machines are not in use à ¢-   Staff provided with ear defenders or suitable hearing protection when required à ¢-   Machinery is maintained to ensure they run as quietly as possible No further action required The essential questions which are asked in regards to the product are: How can each part fail? What might cause this failure? What will the effects of failure be? How serious are these failures? How are the failures detected? Component Potential Failure Potential effects of failure Severity Potential causes of failure How will failure be detected Action to control risk Plastic Parts Breaking Unusable and possible tablet breakage II End user misuse Visual Instructions provided Plastic Parts Melting Product wont function II End user misuse Visual Instructions provided Plastic Parts Wear and tear Unstable I Overuse Visual Warranty Plastic Parts Causing harm End user harm. Potential Legal issues III Finishing Visual Instructions provided Pivot Screws Breaking Unusable and possible tablet breakage II End user misuse Visual Instructions provided Pivot Screws Wear and tear Still usable but not 100% I Overuse Visual Warranty The level of risk is determined by: Risk = probability of failure * Severity factor Severity Categorised Category Probability Description I Minor Functional failure of part of machine or process no potential for injury II Critical Failure will probably occur without major damage to system or serious injury III Major Major damage to system and/or potential serious injury or personal IV Catastrophic Failure causes complete system loss and/or potential for fatal injury Probability Categorised Level Probability Individual failure mode A 10-1 Frequent Likely to occur frequently B 10-2 Probable Likely to occur several times in the life of the product C 10-3 Occasional Likely to occur sometime in the life of the product D 10-4 Remote Unlikely to occur but possible E 10-5 Improbable So unlikely that occurrence may not be experienced A RP1 High Risk B RP2 C RP3 Medium Risk D Low Risk E I II III IV Severity Category Legislation The company currently adheres to ISO 9001:2008 for the plastic sector which aims to improve the efficiency of all operations within the sector, whether in manufacturing or distributing. 2.4 Details of the final design 3.1 Product Evaluation. When evaluating the design there are a wide range of methods and strategies. The one used in this instance is: F.A.C.E. value Function What does it do and how does it work? Aesthetics Is it attractive, why and what makes it so? Construction What is it made from, how and why? Economics How much does it cost and is this good value for money? Function: The stand will hold a number of current products in landscape or horizontal position for ease of use. Aesthetics: The product was never designed to be good looking but functional. Construction: The product was eventually made from ABS plastic resin due to its properties and cost. The constructed parts are held together with pivot screws due to their cost and ease of use. Economics: The customer had given us a maximum price to work too which enabled us to use strict guidelines when it came to purchasing products. Most of the materials were imported from China due to price issues. Although the product may seem good value money from our point of view, this may not be replicated by the end customer. 3.2 Team Working. Although everyone was not capable of working within a team, the selected group which were proved that teamwork has many benefits. The team worked more efficiently and speed was also increased compared to individual workers. This method also offered support for any members ideas. Creativity Increases: The group brainstorming activity process provided incredible results. Everyone came up with their own vision of the best way of creating the product to the customer needs. The team then decided which idea was the best and then continued to develop this in detail together. This was an invaluable process where team members could give instant feedback on what they thought what would and wouldnt work. Speed: Individuals have different strengths and weaknesses. When it came to tackling the project together the team delegated the workload among themselves according to each others skills. This no only saved time but it also allowed distribution of work within the team ensuring everything was done in the best possible way. Effect on Worker Morale: As staff members were working closely together as a successful team, they spend more time together and begin to know each other. This then created a good relationship between the employees. They started to feel proud of what they had achieved ad contributed to the project which also made them feel good about themselves. This seemed to help their self-esteem. Effect on Individual Responsibility: The overall product was produced by teamwork; all the team members felt they had to deliver to their highest abilities. Everyone had a clear understanding that they were responsible for a specific task and the entire team was depending on them doing a good job. 3.3 Evaluation of Safety During the design process safety was one of the main aspects to consider. Many materials were considered but due too certain aspects whether it was finishing or the product being fire retardant. ABS was eventually picked as this would reduce risk in the overall design of the product. The risk assessments carried out for the workplace proved invaluable as this gave the company a clear indication of what was currently being done within the working environment and what could still be done to improve the safety.

Energy Efficient Building Design Strategies For Hot Climates Construction Essay

Energy Efficient Building Design Strategies For Hot Climates Construction Essay This research discusses energy efficient design strategies of traditional houses in Iraq (hot-arid climate), climatic design techniques and potentials for renewable energy systems that can be implemented in the contemporary residential design techniques in order to offset the absence of produced energy (due to current economic and political issues) and help decreasing demand for electricity, which is used extensively to overcome the indoor thermal discomfort during the harsh summer seasons. A comparison between traditional Baghdadi house (Hosh), which existed before the discovery of oil, and a contemporary house design option is to be made to evaluate the thermal performance of both options in this climatic zone in order to adapt more energy efficient design strategies; and also to integrate features for sustainable building design and potentials to implement renewable energy systems. A simulation modeling is to be used to conduct analysis of energy efficient design strategies, namely relating to building envelope, size and direction, ventilation, shading elements, and using renewable energy systems in order to present recommendations that helps in consequential energy offset while preserving comfort. Keywords: Introduction Examining the energy demand in such region, buildings, with particular reference to residential houses, are one of the most significant energy-sensitive entities (Al-ajmi Hanby, 2008). It is stated that buildings consume over half of all electricity and one-third of natural gas (Yilmaz, 2007). Reduction of energy consumption in residential buildings is a major aim worldwide and is a particular challenge in this region for the reasons mentioned previously (Al-ajmi Hanby, 2008). Therefore, sustainable design strategies are of great importance nowadays in order to reduce energy consumption in residential buildings. One may say that sustainability was already a driving force in the past, showing its validity in those days in different forms and techniques. Therefore, problems and precautions in design and construction did not change fundamentally, although a lot of development was seen in materials and technology. Of course, these developments may have had some negative effects (Yilmaz, 2007). Energy efficient design strategies for traditional houses in such climate are significantly different from each other as it can be easily seen in the traditional design (Yilmaz, 2007). Description of Problem Area Energy consumption is becoming more and more important in todays world because of a possible energy shortage in the future. Efficient use of energy has become a key issue for the most energy policies (Yilmaz, 2007). In regions where hot-arid climatic zone is prevailed, practically in Iraq, present economic and political circumstances have become the main reasons that led to a significant energy shortage although Iraq has a spare operational capacity of oil supply in comparison with other countries around the world. A significant need for new energy efficient design strategies and developed buildings construction standards in this area has become essential in order to offset the absence of produced energy and help decreasing demand for electricity, much of which is consumed in air conditioning systems, which is used extensively to overcome the indoor thermal discomfort during the harsh summer seasons (Al-ajmi Hanby, 2008). Conceptual Framework Figure (1) provides a diagram of the conceptual framework that has devised for this research. The proposed research study into traditional and contemporary building design systems will rely on an experimental research strategy in the positivist system of inquiry (developed design strategies). The research will attempt to establish a comparison (Groat and Wang, 2002, P. 254) between a treatment (independent variable) and an outcome (dependent variable) through the evaluation of measured results. Figure (1) Conceptual diagram of the research variables (Groat Wang, 2002) Research Questions Do traditional houses perform better than contemporary ones? Why? Is it feasible to use traditional design strategies in contemporary houses? How could we achieve a sustainable building design in such climatic zone? Do we need new or developed strategies in order to achieve sustainable building design in such climatic region? What if we integrate renewable energy systems into traditional house design? Project Goals and Specific Objectives The purpose of this research is to: Make a comparison and evaluation of thermal performance of residential houses (traditional vs. contemporary) in Iraq (hot-arid climate) in order to adapt more developed and energy efficient design strategies. Integrate new trends for sustainable design in residential houses in this area. Potentials to implement renewable energy systems. This research is achieved through the following: Extensive overview of the antecedent literature in the area of energy efficiency and thermal building performance in such climatic zone. Identify the most effective strategy from the literature that can be applied in order to develop more energy efficient design strategies. Un-wrap issues of energy efficiency, building performance and sustainable design systems. Use a simulation modeling as a tactical tool to make comparison between contemporary and traditional building design systems and energy performance in order to investigate the thermal characteristics and energy savings for both building designs using different strategies and also potentials to integrate sustainable features using renewable energy system. Test outcome results and write a research report accordingly which combines my understanding of the relevant theory and previous research with the results of my empirical research. Literature Review The literature review is structured around the key concepts of significance of energy efficient design strategies, thermodynamics of hot-arid climates, Inventory of traditional design elements in hot-arid climate and energy simulation methods. These key concepts have led to the research questions and the proposed methodology for this research proposal. See figure1 for the map of literature reviewed. Figure () Map of sources reviewed Figure () Research Literature Review Diagrammatic (Groat Wang, 2002) Building Design Strategies Climatic Building Strategies Research by Ochoa Capeluto (2008) states a quick review of design strategies for different climatic zones. This is necessary to examine when and how design strategies should be considered, particularly during design process. Climatic building strategies in hot climates differ from those of cold ones, For example, in cold climates heat collection and storage is essential, and ventilation must be limited for the same reasons. Short daytime and low radiation levels in winter make maximum penetration of natural light to be desired. On the other hand, in hot climates heat must be excluded, the amount of relative humidity controlled, and the thermal mass cooled usually through natural ventilation during the night. Daylight penetration must be carefully managed using control devices (see figure 1) (as cited in Ochoa Capeluto, 2008, Building and Environment, P.1830). Figure (1) Building strategies for cold and hot climates (Ochoa Capeluto, 2008). Optimized Building Envelope A building envelope is a skin that separates between the interior and the exterior of a building. It serves as the outer shell to protect the indoor environment as well as to facilitate its climate control (controlling heat transfer between building layers). The study by Danny Harvey (2009) reviews the literature concerning energy efficiency that can be achieved through optimized building envelope. According to Danny Harvey (2009), The effectiveness of the thermal envelope depends on: (1) The insulation levels in the walls, ceiling, and other building parts; (2) The thermal properties of windows and doors; and (3) The rate of uncontrolled exchange of inside and outside air which, in turn, depends in part on the air tightness of the envelope (infiltration/excitation) (Energy Efficiency, P. 141). Reducing the Cooling Load Energy conservation and climatic design techniques that can be implemented in residential houses in this area (hot-arid climate) are useful for reducing cooling energy consumption (Al-Temeemi, 1995). Danny Harveys (2009) research found the following: Reducing the cooling load requires: (1) Orienting a building to minimize the wall area facing directions that are most difficult to shade from the sun; (2) Clustering buildings to provide some degree of self shading (as in many traditional communities in hot climates); (3) Providing fixed or adjustable shading; (4) Using highly reflective building materials; (5) Increasing insulation; (6) Using windows that transmit a relatively small fraction (as little at 25%) of the total (visible + invisible) incident solar energy while permitting a larger fraction of the visible radiation to enter for daylighting purposes; (7) Utilizing thermal mass to minimize daytime interior temperature peaks; (8) Utilizing night time ventilation to remove daytime heat; and (9) Minimizing internal heat gains by using efficient lighting and appliances. The combination of external insulation, thermal mass, and night ventilation is particularly effective in hot-arid climates, as placing the insulation on the outside exposes the thermal mass to cool night air while minimizing the inward penetration of daytime heat into the thermal mass (Energy Efficiency, P. 141). Passive cooling techniques By using the above measures to reduce the thermal load of the building, other techniques requires small inputs of mechanical energy to optimize passive cooling processes (Danny Harvey, 2009). Danny Harveys (2009) research discussed the following major passive cooling techniques: Passive ventilation Passive ventilation reduces the need for mechanical cooling by directly removing warm air when the incoming air is cooler than the outgoing air, reducing the perceived temperature due to the cooling effect of air motion and increasing the acceptable temperature through psychological adaptation when the occupants have control of operable windows. Passive ventilation requires a driving force, and an adequate number of openings, to produce airflow. It can be induced through pressure differences arising from inside-outside temperature differences or from wind. Design features, especially traditional, that create thermal driving forces and/or utilize wind effects include courtyards, atria, wind towers, solar chimneys, and operable windows. Passive ventilation not only reduces energy use, but can improve air quality and gives people what they generally want. In buildings with good thermal mass exposed to the interior air, passive ventilation can continue right through the night, sometimes more vigorously than during the day due to the greater temperature difference between the internal and external air. Night time ventilation, in turn, serves to reduce the cooling load by making use of cool ambient air to remove heat (as cited in Danny Harvey, 2009, Energy Efficiency, P.142). Evaporative cooling Danny Harveys (2009) study further discussed the following in terms of producing evaporative cooling techniques: Evaporation of water cools the remaining liquid water and air that comes into contact with it. The coldest temperature that can be achieved through evaporation is called the wet-bulb temperature and depends on the initial temperature and humidity (the higher the initial humidity, the less evaporation and cooling that can occur). There are two methods of evaporative cooling the air supplied to buildings. In a direct evaporative cooler, water evaporates directly into the air stream to be cooled. In an indirect evaporative cooler, water evaporates into and cools a secondary air stream, which cools the supply air through a heat exchanger without adding moisture. By appropriately combining direct and indirect systems, evaporative cooling can provide comfortable temperature-humidity combinations most of the time in most parts of the world. Evaporative cooling is most effective in dry regions, but water may be a limiting factor in such regions. However, arid regions tend to have a large diu rnal temperature range, so thermal mass with external insulation and night ventilation can be used instead (Energy Efficiency, P.142). Influence of Energy Efficient Design Strategies on Design Stages The architectural design process is iterative and moves from the abstract (definition of massing, orientation, and image) to the specific (lighting control, mechanical ventilation type) (as cited in Ochoa Capeluto, 2008, Building and Environment, P.1830). At the design stage, key decisions taken by architects can significantly influence potentials to optimize building efficiency. These include decisions affecting the selection of building components. According to Ochoa Capeluto (2008), As it advances and more specialists are called in to solve details, earlier decisions, which could have an enormous influence on the building performance, are expensive and harder if not impossible to change (Building and Environment, P.1830). Other influential factors unrelated to climatic strategies must be taken into account. For example, a certain orientation that is bad for energy consumption might define how well the building performs (Ochoa Capeluto, 2008). However, it would require an Integrated Design Process (IDP), in which the design process optimizes the building performance by involving all members of design-making team from the beginning. The importance of an Integrated Design Process (IDP) on building systems approach Danny Harveys (2009) study found the following: The systems approach requires an Integrated Design Process (IDP), in which the building performance is optimized through an iterative process that involves all members of the design team from the beginning. However, the conventional process of designing a building is a largely linear process, in which the architect makes a number of design decisions with little or no consideration of their energy implications and then passes on the design to the engineers, who are supposed to make the building habitable through mechanical systems (Energy Efficiency, P. 140). The steps in the most basic IDP are: to consider building orientation, form, and thermal mass to specify a high-performance building envelope to maximize passive heating, cooling, ventilation, and daylighting to install efficient systems to meet remaining loads to ensure that individual energy-using devices are as efficient as possible and properly sized to ensure the systems and devices are properly commissioned By focusing on building form and a high-performance envelope, heating, and cooling loads are minimized, daylighting opportunities are maximized, and mechanical systems can be greatly downsized (Danny Harvey, 2009). Thermodynamics of Hot-Arid Climates Any consideration to energy efficiency applications or design strategies in any climatic zone requires examining of thermodynamics and human comfort. In his Text Natural Energy and Vernacular Architecture: Principles and Examples, With Reference to Hot Arid Climates, the author demonstrates properties of energy that must be considered in order to fully understand climatic phenomena. Heat, radiation, pressure, humidity, and wind, among other factors, interact mutually to establish microclimatic conditions appropriate to hot-arid climatic (Fathy, 1986). According to Fathy (1986), the following are some of these basic concepts applied to hot-arid climates: Thermal gain Solar radiation is the principal source of heat in hot-arid zones, and this heat can be transmitted during the day to the building interior in a number of ways. The most important is by conduction of the absorbed solar radiation through the walls or roof at a rate determined by the thermal conductance (or thermal resistivity) of wall components. (The relationship involving the incoming and reflected solar radiation absorbed and re-emitted heat and heat gain is shown in figure 2 below for the case of a typical white painted surface). Figure (2) (Fathy, 1986) Heat gain can also be caused by ventilation. The rate of gain is dependent on the ventilation rate. Ventilation heat gain can be avoided by restricting the size of openings, especially during the heat of the day. The other sources of heat gain are the inhabitants of the building themselves and household equipment such as electric lights and appliances. These sources, unlike the solar radiation, can contribute heat even at night (see figure 3) (Fathy, 1986). Figure (3) Modes of heat transfer (Fathy, 1986) Thermal loss Heat is lost by conduction through the walls, by exactly the same process that it is gained from the direct solar radiation once it has been absorbed by the surface or through the roof by a combination of convection and conduction. Ventilation is also another mode of heat loss. Evaporation from the surface of the building or from objects within the interior can produce a cooling effect on the building which acts as a source of heat loss. In hot arid climates, this can be a particularly effective cooling mechanism since the rate of evaporation in dry air is very high. Figure 3 also shows the modes of heat loss (Fathy, 1986). Cooling by evaporation Evaporative cooling is used for cooling in hot dry areas (such as in Iraq, where the people place against the windows panels of dried desert plants, which are kept moist by water dripping from perforated pipes positioned above them) (Fathy, 1986). Dynamic thermal equilibrium The heat gained by the building can be expected to be balanced by the heat lost and an internal temperature distribution thus established. These temperatures are dependent on the outside temperature and the ratio of the heat gained to the heat lost and can be adjusted by regulating the sources of heat gain and loss. Before examining the systems and devices that have been developed to do this in the hot arid zones, it is first necessary to have an idea of the heat-regulating mechanism of the human body and the microclimatic conditions for human comfort. Table (1) Heat gain and loss processes for the human body (Fathy, 1986). Mechanism Gain Process Loss Process Metabolism Basal heat production Digestion Activity Muscle tensing and shivering in response to cold Radiation From solar radiation-direct and reflected To surrounding air From radiation by radiators Conduction From air above skin temperature (increased by air movement) To air below skin temperature From warmer bodies in contact To cooler bodies in contact Evaporation From respiratory tract From skin covered with perspiration or applied water Conditions of human comfort A convenient standard for thermal comfort is required. Analysis shows that a variety of factors can be involved in situations of discomfort. For example, temperature alone does not determine discomfort. In Athens, 32  °C is quite bearable, but it is generally intolerable in Bahrain. The difference is due entirely to the relative humidity of the atmosphere. In Bahrain the air is very humid and perspiration evaporates slowly, decreasing the bodys ability to lose heat. In Athens, with its dry air, the evaporation rate is high and perspiration evaporates quickly lowering body temperature. The factors that have been identified as standard for thermal comfort within buildings are: air temperature, air humidity, rate of air movement, level of radiation, and rate of heat production by the bodies of people in the building [4]. Inventory of design elements for traditional housing design in hot-arid climates Building materials The materials surrounding the occupants of a building are of prime importance for protection against heat and cold. Considering an external wall exposed to a high outside air temperature and a lower inside air temperature (see figure 4), the rate of heat flow transmitted through the wall from the outside air to the inside air is proportional to the air temperature difference, area of the wall, and rate of global heat transmittance that can be determined from an analysis of the components of the total resistance to heat flow. The total resistance is composed of the resistance to heat flow through the material, the interfacial resistance at the external surface, and the interfacial resistance at the internal surfaces. Since the interfacial resistances are determined primarily by temperature conditions over which the builder has little control, his principal effect on the heat transmittance is on changing the resistance to heat flow through the wall material (Fathy, 1986). Figure (4) (Fathy, 1986) Table 2 lists the thicknesses of walls composed of various construction materials needed to achieve coefficients of approximately 1.1 kcal/hm ²C °. The mud brick is most appropriate for achieving thermal comfort in addition to being widely available to all segments of the population (Fathy, 1986). Table (2) Thicknesses of walls of different material (Fathy, 1986) Wall Material Wall Thickness Thermal Transmittance (in m) (in in) (in kcal/ hm ²C °) Hollow brick block 0.30 12 1.10 Double-wall brick with holes and 8-cm cavity 2 x 0.12 2 x 4.7 1.12 Brick wall with holes 0.38 15 1.03 Sand-lime brick 0.51 20 1.25 Hollow block sand-lime brick 0.51 20 1.16 Lime 0.51 20 1.10-1.35 Concrete 1.00 39 1.20 Orientation In hot climates, the sun is the major source of heat. The position of the sun must be determined for all hours of the day at all seasons as well as the direction of the prevailing winds, especially during the hot season. In addition, for an ensemble of buildings forming a sector, there will be reflection from adjacent buildings and wind screening by clusters of buildings, which contribute to a specific microclimate for each location in the sector. Wind movement and humidity also are important and should be considered simultaneously with the direct and indirect effects of the sun. The main objective is to establish the optimum orientation with regard to the sun and the prevailing wind (Fathy, 1986). Shading Generally, a building with a facade opening to the west is the worst case encountered in hot-arid climate, owing to the heat gain of the surrounding environment during the day and the angle of altitude, which allows the suns rays to penetrate into the interior. Openings Window openings normally serve three functions: to let in direct and indirect sunlight, to let in air, and to provide a view (Fathy, 1986). The venetian blind One device which can be added directly to the window is the venetian blind. This blind is made of small slats, about 4-5 cm wide, closely set in a wooden frame at an angle that will intercept the suns rays. The slats are often movable so the angle can be changed. This feature of adjustability renders venetian blinds very useful in regulating solar radiation and wind flow into rooms. Using the venetian blind, the suns rays can be blocked out without obstructing the breeze, which generally blows from the northwest in most hot arid areas like Iraq. As shown in figure 5a, changing the position of the blind alternatively by to block the direct sunlight, the wind is redirected uselessly over the heads of the occupants, as figure 5b illustrates. Also, if the slats are made of metal, they then absorb some incoming radiation and reradiate it into the room as heat (Fathy, 1986). Figure (5) (Fathy, 1986) The Shanshool or Mashrabiya This was a cantilevered space with a lattice opening, where small water jars were placed to be cooled by the evaporation effect as air moved through the opening. The name is used for an opening with a wooden lattice screen composed of small wooden balusters that are circular in section and arranged at specific regular intervals. The shanshool has five functions. These functions involve: (1) controlling the passage of light, (2) controlling the air flow, (3) reducing the temperature of the air current, (4) increasing the humidity of the air current, and (5) ensuring privacy. Its cooling and humidifying functions are closely related. All organic fibers, such as the wood of a shanshool readily absorb, retain, and release considerable quantities of water. Wind passing through the interstices of the porous-wooden shanshool will give up some of its humidity to the wooden balusters if they are cool, as at night. When the shanshool is directly heated by sunlight, this humidity is released to any air that may be flowing through the interstices. This technique can be used to increase the humidity of dry air in the heat of the day, cooling and humidifying the air at a time when most needed. The balusters and interstices of the shanshool have optimal absolute and relative sizes that are based on the area of the surfaces exposed to the air and the rate at which the air passes through. In addition to these physical effects, the shanshool serves an important social function: it ensures privacy from the outside for the inhabitants while at the same time allowing them to view the outside through the screen (Fathy, 1986). Table (3) Summary of architectural elements of traditional building in Iraq (hot-arid climate), as they have been common from the 13th to the end of the 19th century. Retrieved from http://www.brainworker.ch/Irak/architecture.htm Oda: the simple room Tarma: open balcony with pillars Ursi: most probably from russi, russian. The most important room of the house, as at the same time you may see, but not been seen as much as in a tarma, ivan or talar. Its separated from the tarma by a window-wall from colored glasses, without door. Those were the masterpieces of Baghdadi carpentry. Talar, a usable open room behind the tarma. The difference to the iwan is, that it cant be entered directly from the rooms beside it. Is separated from the tarma by additional pillars. Iwan(or Liwan), a room behind the tarma or adjacent tot the inner courtyard, that is on one side open. Hosh, the central courtyard, often with a fountain in the middle. sirdab, the cellar, that did not only serve as store, but   as cooling hall and for the provision of cool air through the badgir-sirdab-system. neem, a cellar that is only half buried. Mostly with one window. During the hot summer nights the roof was and is used in Baghdad for sleeping. The high value of privacy demanded, that no house was higher than the others, so that nobody was able to look down on his neighbors roof. kabishkan: The Penthouse, from where one is able to control all the house. Often those rooms have been placed like eyries in all four corners of the inner courtyard.   The roof If the outdoor air temperature is higher than the indoor temperature, the outer surface of the roof exposed to the sun is heated as it absorbs radiation, and, being in contact with the outside hot air, also is heated by conduction. The roof then transmits this heat to the inner surface, where it raises the temperature of the air in contact with it by conduction. At the same time, it radiates heat that is absorbed by people and objects indoors, thereby affecting thermal comfort. In hot arid countries, since the air temperature drops considerably during the night, the inhabitants have arranged the roof architecturally into loggias or open galleries and lightweight roof covers. These loggias and roof covers have the double function of shading the roof during the day and providing physiologically comfortable living and sleeping spaces at night (Fathy, 1986). Figure (6) Different types of roofing in hot-arid climates (Fathy, 1986) The wind-escape The technique of using the suction caused by low air-pressure zones to generate steady air movement indoors is used in the design of the wind-escape. The funnel and side tube used to illustrate the Bernoulli effect or Venturi action (see figure 7) are transposed into the structural elements of an architectural design in order to accelerate air movement and to create drafts in places with no exposure to the outside, such as basements in Iraq. This concept can be applied more advantageously in designs for use above ground. The wind-escape can accelerate effective ventilation and air circulation when used with other devices for air movement such as windows, doors, and the malqaf or wind-catch (Fathy, 1986). Figure (7) Bernoulli Effect (Fathy, 1986) The malgaf In hot arid zones, a difficulty is found in combining the three functions of the ordinary window: light, ventilation, and view. Therefore, it is necessary to satisfy the three functions ascribed to the window separately. To satisfy the need for ventilation alone, the malqaf or wind-catch was invented. This device is a shaft rising high above the building with an opening facing the prevailing wind. It traps the wind from high above the building where it is cooler and stronger, and channels it down into the interior of the building. The malqaf thus dispenses with the need for ordinary windows to ensure ventilation and air movement. The malqaf is also useful in reducing the sand and dust so prevalent in the winds of hot arid regions. The wind it captures above the building contains less solid material than the wind at lower heights, and much of the sand which does enter is dumped at the bottom of the shaft. In the areas of An-Najf and Al-Kufa in Iraq, where air temperature is very high in summer, people live in basements ventilated by small holes in the ceiling and a malqaf with a very small inlet. Figure 8 shows plans and the section of a residence with a basement from this region. However, as the airflow is small and the air circulation is insufficient, this design is unhealthy and a possible cause of lung diseases. In some designs, the drafts from the malqaf outlet are cooled by passing over water in the basement. Figure (8) The Malgaf (Fathy, 1986) The Bà £dgir-sirdab In Iraq (hot-arid climate)and the countries of the Gulf, a specific type of malqaf called the bà £dgir was developed. The system badgir-sirdab was a cheap, environmentally friendly and energy saving solution to create an acceptable cl