Why Software Systems Fail Essay Example For Students

Why Software Systems Fail Essay 1.0 IntroductionIn this report I will be concentrating on the failure of software systems. To understand why software systems fail we need to understand what are software systems. Software systems are a type of information system. This is because a software system is basically a means for hardware to process information. Flynns definition of an information system is:An information system provides procedures to record and make available information, concerning part of an organization, to assist organization-related activities.Humans have been processing information manually for thousands of years, but with the vast increase of demand for knowledge this century has meant that a new method of information processing has been needed. Software systems have provided a new means that is much faster and efficient. As a result a huge number of organisations have become software dependent. Some of these systems are used to safeguard the lives of many people. This means that if these systems wer e to fail they could lead to devastating consequences. Here are some examples of where software systems are used heavily and could be very dangerous if they were to fail aviation, hospitals, space exploration, nuclear power stations and communications. I will be looking at some examples of actual software failure in these fields to explain the reasons why systems fail.2.0 Reasons for Systems FailureIf software systems failure can be so dangerous why can they not be completely eliminated? According to Parnas, The main reason is that software can never be guaranteed to be 100% reliable. Software systems are discrete-state systems that do not have repetitive structures. The mathematical functions that describe the behaviour of software systems are not continuous, and traditional engineering mathematics do not help in their verification. In other words some software can be so large that thorough testing can be almost impossible and so bugs in the software can go unnoticed. An example o f this was when an Atlas-Agena rocket veered off-course when it was ninety miles up. Ground control had to destroy the $18.5 rocket. The reasons for this a missing hyphen. However there are many more reasons for software systems failure, and most of them are due to human negligence that leads to software failure. There are two types of software systems failure. These are in the design stage of the software or in the implementation of the software. These are the main reasons for systems failure.Poor software design Fundamental flaws in the design of the software.Incorrect requirements specifications The brief is inconsistent or missing vital information. Political / Commercial pressures This can lead to developers skipping parts of the system to save time or money. There are also cases of rivalry between sub-contractors, which damages the design of the system.Incorrect analysis and assumptions Predictions based on incorrect assumptions of the real world or its behaviour.Not prop erly tested software implemented in a high risk environment This is almost guaranteed to lead to systems failure.Poor user-interface Makes it difficult or even impossible for the user to operate the software system.Incorrect fit between software and hardware Incorrect specification of the hardware type in the brief, or upgrading the hardware without upgrading the software (or vice-versa).Inadequate training given to the operators The people who have to use the software are not taught properly how to use the software system or they are expected to learn on their own. Over reliance on the software system The operators expect their software system to work in all conditions and to perform miracles for them.I will be looking at these types of systems failure with examples. 2.1 Poor software design- the Denver airport automated luggage handling systemAn example of poor software design is the Denver International Airport luggage controller. In this case Jones says that the senior exec utives did not have a sufficient background in software systems and as a result accepted nonsensical software claims at face value.The airport boasted about its new automated baggage handling system, with a contract price of $193 million, will be one of the largest and most sophisticated systems of its type in the world. It was designed to provide the high-speed transfer of baggage to and from aircraft, thereby facilitating quick turnaround times for aircraft and improved services to passengers. The baggage system, which came into operation in October 1995, included over 17 miles of track; 5.5 miles of conveyors; 4,000 telecarts; 5,000 electric motors; 2,700 photocells; 59 laser bar code reader arrays; 311 radio frequency readers; and over 150 computers, workstations, and communication servers. The automated luggage handling system (ALHS) was originally designed to carry up to 70 bags per minute to and from the baggage check-in.However there were fundamental flaws identified but not addressed in the development and testing stage. ABC news later reported that In tests, bags were being misloaded, misrouted or fell out of telecarts, causing the system to jam. The Dr. Dobbs Journal (January 1997) also carried an article in which the author claims that his software simulation of the automatic baggage handling system of the Denver airport mimicked the real-life situation. He concluded that the consultants did perform a similar simulation and, as a result, had recommended against the installation of the system. However the city overruled the consultants report and gave the go-ahead (the contractors who were building the system never saw the report).The report into the failure of the Denver ALHS says that the Federal Aviation Authority had required the designers (BAE Automated Systems Incorporated) to properly test the system before the opening date on 28th February 1995. Problems with the ALHS had already caused the airports opening date to be postponed and no furth er delays could be tolerated by the city. The report speculates that delays had already cost the airport $360 million by February 1995.The lack of testing inevitably led to problems with the ALHS. One problem occurred when the photo eye at a particular location could not detect the pile of bags on the belt and hence could not signal the system to stop. The baggage system loaded bags into telecarts that were already full, resulting in some bags falling onto the tracks, again causing the telecarts to jam. This problem caused another problem. This one occurred because the system had lost track of which telecarts were loaded or unloaded during a previous jam. When the system came back on-line, it failed to show that the telecarts were loaded. Also the timing between the conveyor belts and the moving telecarts were not properly synchronized, causing bags to fall between the conveyor belt and the telecarts. The bags then became wedged under the telecarts. This eventually caused so many pr oblems that there was a need for a major overhaul of the system.The government report concluded that the ALHS at the new airport was afflicted by serious mechanical and software problems. However you can not help thinking how much the city was blamed for their part in a lack of demand for proper testing. Denver International Airport had to install a $51 million alternative system to get around the problem. However United Airlines still continue to use the ALHS. A copy of the report can be found at http://www.bts.gov/smart/cat/rc9535br.html.2.2 Political / Commercial pressures the Challenger DisasterThere are many examples of failures occurring because of this. One of the most famous examples of these is the Challenger disaster. On the 28th January 1986 the challenger space shuttle exploded shortly after launch, killing all seven astronauts onboard. This was initially blamed on the design of the booster rockets and allowing the launch to proceed in cold weather. However it was later revealed that there was a decision along the way to economize on the sensors and on their computer interpretation by removing the sensors on the booster rockets. There is speculation that those sensors might have permitted earlier detection of the booster-rocket failure, and possible early separation of the shuttle in an effort to save the astronauts. Other shortcuts were also taken so that the team could adhere to an accelerated launch sequence. (Neumann). This was not the first time there had been problems with space shuttle missions. A presidential commission was set up and the Chicago Tribune reported what some astronauts said, that poor organization of shuttle operations led to such chronic problems as crucial mission software arrived just before shuttle launches and the constant cannibalization of orbiters for spare parts. Obviously the pressures of getting a space shuttle launch and mission to run smoothly and on time is huge. However there has to be a limit on how many short cuts can be taken. Another example of commercial pressure is the case of a Fortune 500 company. (A Fortune 500 company is one that appears in a listing of the top 500 U.S. companies ranked by revenues, according to Fortune magazines classic list.) According to Jones, the client executive and the senior software manager disliked each other so intensely that they could not never reach agreement on the features, schedules, and effort for the project (a sales support system of about 3000 function points). They both appealed to their higher executives to dismiss the other person. The project was eventually abandoned, after acquiring expenses of up to $500 000. Jones reported another similar case in a different Fortune 500 company. two second-line managers on an expert system (a project of about 2500 function points) were political opponents. They both devoted the bulk of their energies to challenging and criticizing the work products of the opposite teams. Not surprisingly the project w as abandoned after costing the company $1.5 million.2.3 Incorrect analysis and assumptions the Three Mile Island accidentIncorrect assumptions can seem very obvious when they are thought about, however it does not stop them from creeping in. According to Neumann a Gemini V rocket landed a hundred miles off course because of an error in the software. The programmer used the Earths reference point relative to the Sun, as elapsed time since launch, as a fixed constant. However the programmer did not realise that the Earth position relative to the Sun does not come back to the same point 24 hours later. As a result the error accumulated while the rocket was in space. The Three Mile Island II nuclear accident, on 28th March 1979, was also blamed on assuming too much. The accident started in the cooling system when one of the pipes became blocked, resulting in the temperature of the fuel rods increased from 600 degrees to over 4000 degrees. Instruments used to measure the temperature of the reactor core was not standard equipment at the time, however thermocouples had been installed and could measure high temperatures. However after the temperature reached over 700 degrees the thermocouples had been programmed to produce a string of question marks instead of displaying the temperature. After the reactor started to over-heat the turbines shut down automatically. However this did not stop the rods from over-heating as someone had left the valves for the secondary cooling system closed. There was no way of knowing this at the time because there was no reading on the temperature of the reactor core.Operators testified to the commission that there were so many valves that sometimes the would get left in the wrong position, even though their positions are supposed to be recorded and even padlocked. This is also a case of the designers blaming the operators and vice-versa. In the end the operators had to concede reluctantly that large valves do not close themselves.Petros ki says, Contemporaneous explanations of what was going on during the accident at Three Mile Island were as changeable as the weather forecasts, and even as the accident was in progress, computer models of the plant were being examined to try to figure it out. Lots of assumptions had been made about how high the temperature of the reactor core could go and the state of the valves in the secondary cooling system. This shows that in an environment where safety is supposed to be the number one issue people are still too busy to think about all the little things all the time and high pressure situations develop that compromise the safety of hundreds of thousands of people. It took until August 1993 for the site to be declared safe. Facts are taken from Neumann and Perrow.2.4 Not properly tested software implemented in a high risk environment the London Ambulance ServiceThe failure of the London Ambulance Service (LAS) on Monday and Tuesday 26 and 27 November 1992, was, like all major fa ilures, blamed on a number of factors. These include inadequate training given to the operators, commercial pressures, no backup procedure, no consideration was given to system overload, poor user interface, not a proper fit between software and hardware and not enough system testing being carried out before hand. Claims were later made in the press that up to 20-30 people might have died as a result of ambulances arriving too late on the scene. According to Flowers, The major objective of the London Ambulance Service Computer Aided Despatch (LASCAD) project was to automate many of the human-intensive processes of manual despatch systems associated with ambulance services in the UK. Such a manual system would typically consist of, among others, the following functions: Call taking. Emergency calls are received by ambulance control. Control assistants write down details of incidents on pre-printed forms.The LAS offered a contract for this system and wanted it to be up and running by 8th January 1992. All the contractors raised concerns about the short amount of time available but the LAS said that this was non-negotiable. A consortium consisting of Apricot, Systems Options and Datatrak won the contract. Questions were later asked about why there contract was significantly cheaper than their competitors. (They asked for 1.1 million to carry out the project while their competitors asked for somewhere in the region of 8 million.)The system was lightly loaded at start-up on 26 October 1992. Staff could manually correct any problems, caused particularly by the communications systems such as ambulance crews pressing the wrong buttons. However, as the number of calls increased, a build up of emergencies accumulated. This had a knock-on effect in that the system made incorrect allocations on the basis of the information it had. This led to more than one ambulance being sent to the same incident, or the closest vehicle was not chosen for the emergency. As a consequence, the system had fewer ambulance resources to use. With so many problems the LASCAD generated exception messages for those incidents for which it had received incorrect status information. The number of exception messages appears to have increased to such an extent the staff were not able to clear the queues. Operators later said this was because the messages scrolled of the screen and there was no way to scroll back through the list of calls to ensure that a vehicle had been dispatched. This all resulted in a viscous circle with the waiting times for ambulances increasing. The operators also became bogged down in calls from frustrated patients who started to fill the lines. This led to the operators becoming frustrated, which in turn led to an increased number of instances where crews failed to press the right buttons, or took a different vehicle to an incident than that suggested by the system. Crew frustration also seems to have contributed to a greater volume of voice radio traff ic. This in turn contributed to the rising radio communications bottleneck, which caused a general slowing down in radio communications which, in turn, fed back into increasing crew frustration. The system therefore appears to have been in a vicious circle of cause and effect. One distraught ambulance driver was interviewed and recounted that the police are saying Nice of you to turn up and other things. At 23:00 on October 28 the LAS eventually instigated a backup procedure, after the death of at least 20 patients.An inquiry was carried out into this disaster at the LAS and a report was released in February 1993. Here is what the main summary of the report said:What is clear from the Inquiry Teams investigations is that neither the Computer Aided Despatch (CAD) system itself, nor its users, were ready for full implementation on 26 October 1992. The CAD software was not complete, not properly tuned, and not fully tested. The resilience of the hardware under a full load had not been tested. The fall back option to the second file server had certainly not been tested. There were outstanding problems with data transmission to and from the mobile data terminals. Staff, both within Central Ambulance Control (CAC) and ambulance crews, had no confidence in the system and was not all fully trained and there was no paper backup. There had been no attempt to foresee fully the effect of inaccurate or incomplete data available to the system (late status reporting/vehicle locations etc.). These imperfections led to an increase in the number of exception messages that would have to be dealt with and which in turn would lead to more call-backs and enquiries. In particular the decision on that day to use only the computer generated resource allocations (which were proven to be less than 100% reliable) was a high-risk move.In a report by Simpson (1994) she claimed that the software for the system was written in Visual Basic and was run in a Windows operating system. This decis ion itself was a fundamental flaw in the design. The result was an interface that was so slow in operation that users attempted to speed up the system by opening every application they would need at the start of their shift, and then using the Windows multi-tasking environment to move between them as required. This highly memory-intensive method of working would have had the effect of reducing system performance still further.The system was never tested properly and nor was their any feedback gathered from the operators before hand. The report refers to the software as being incomplete and unstable, with the back up system being totally untested. The report does say that there was functional and maximum load testing throughout the project. However it raised doubts over the completeness and quality of the systems testing. It also questions the suitability of the operating system chosen.This along with the poor staff training was identified to be the main root of the problem. The mana gement staff was highly criticised in the report for their part in the organisation of staff training. The ambulance crew and the central control crew staff were, among other things, trained in separate rooms, which did not lead to a proper working relationship between the pair. Here is what the report said about staff training:Much of the training was carried out well in advance of the originally planned implementation date and hence there was a significant skills decay between then and when staff were eventually required to use the system. There was also doubts over the quality of training provided, whether by Systems Options or by LASs own Work Based Trainers (WBTs). This training was not always comprehensive and was often inconsistent. The problems were exacerbated by the constant changes being made to the system.Facts are taken from http://catless.ncl.ac.uk/Risks, http://www.scit.wlv.ac.uk and the report of the Inquiry into the London Ambulance Service, February 1993.2.5 Poor u ser-interfaceThe last case was a good example of how a poor user-interface can lead to mayhem. Another similar case was reported to the Providence newspaper. The Providence (part of New York) police chief, Walter Clark, was grilled over why his officers were taking so long to respond to calls. In one case it took two hours to respond to a burglary in progress. He explained that all the calls are entered into a computer and are shown on a monitor. However the monitor can only show twenty reports at a time as the programmer did not design a scroll function for the screen. The programmer had some serious misconceptions about the crime rate in New York. Facts taken from: http://catless.ncl.ac.uk/Risks.2.6 Over reliance on the software systemThe Exxon Valdez oil disaster was simultaneously blamed on the drunken captain, the severely fatigued third mate, the helmsman and the system. The system refers to the auto-pilot of the ship and the lack of care the crew had on its operation. Accordi ng to Neumann the crew were so tired that they did not realise that the auto-pilot was left on and so the ship was ignoring their rudder adjustments. This example shows that even though everything was working properly, all the safety measures had a minimal effect when they were trying to override the auto-pilot. This is a very small mistake and could easily have been prevented.The Therac-25 case, a system designed to give the right amount of radiation to the patient in chemotherapy treatment also fell into a case foolproofedness. The operators did not imagine the software permitted the therapeutic radiation device to be configured unsafely in X-Ray mode, without its protective filter in place (Neumann). Such blind faith in the system resulted in several patients being given too high a dose that killed the patients.3.0 ConclusionIt is obvious to see from these examples that failures are very rarely due to one cause alone. In major system failures it can be over a dozen mistakes being made that usually results in the failure of the system. Also the mistakes have a domino effect or leads to a viscous circle of mistakes, the systems becoming worse and worse during both the design and implementation stage. In almost all large system failures there is a case of when commercial pressures are put above safety. The Paddington rail crash (5th October 1999) could have been prevented if the train had been fitted with the Train Protection Warning System. This system would physically stop the train if it went through a red signal and was recommended in the report following the train crash at Southall. However it would have cost Railtrack something like 150-200 million. The system will however now be introduced to all trains by 2004. The facts were taken from BBC online.It is obvious that the main reason for the commercial pressures is cost. The Challenger disaster might have been prevented if sensors had not been removed from the booster rockets. But the cost of some extra sensors compared to the already astronomical cost of space exploration makes it seem a little nonsensical. The cost of a space shuttle is well over $1 billion, never mind the damage it did to NASAs reputation. However it is not always cost saving that leads to system failures. In both the Denver ALHS and the London Ambulance System CAD it is more a case of money wasting. When the initial investment has been made a company finds it very hard to terminate the project. They would rather get the system working than admit defeat, whatever the cost. Sometimes the cost can be in terms of human lives. This would be why United Airlines still insist on using the Denver ALHS and twenty people died before the LAS switched their dispatching system. Proper communication and feedback between the designers and the operators will stop a lot of problems like a poor user-interface and incorrect fit between the hardware and software. It all starts with a proper brief being given to the designers. But t his can only happen if the management knows what they want. So the only way to have a successful system is to have good communications and understanding between the designers and operators, with the senior managers being kept in the know at all times. However the most important job is for someone to take responsibility for the design and operation of the system. If someone who is competent is put in charge and takes responsibility then the system is likely to be working properly before its implementation and the operators will have adequate training for using the system. With the London Ambulance System this was doubly important where patients lives are at risk. In situations like these Ethics is the key word and there has to be someone held responsible for the actions of the organisation. 4.0 BibliographyFlynn, Donal J.; Information Systems Requirements: Determination and Analysis; McGraw-Hill Book Company; 1992Parnas; 1985; taken from: Sherer, Susan A.; Software Failure Risk Measu rement and Management; Plenum Press; 1992Jones, Carpers; Patterns of Software Systems Failure and Success; Thomson computer press; 1996Neumann, Peter G.; Computer Related Risks; Addison-Wesley publishing company; 1995Petroski, Henry; To Engineer is Human; MacMillan Publishing; 1985Flowers, Stephen; Software failure: management failure; Chichester: John Wiley and Sons; 1996.Report of the Inquiry into the London Ambulance Service; February 1993. Simpson, Moira (1994); 999!: My computers stopped breathing !; The Computer Law and Security Report, 10; March April; pp 76-81Dr. Dobbs Journal; January 1997 editionhttp://catless.ncl.ac.uk/Riskshttp://www.scit.wlv.ac.uk http://www.bbc.co.uk/newshttp://abcnews.go.com/sections/travel .u58990440ce4e446788d91e3f02a21697 , .u58990440ce4e446788d91e3f02a21697 .postImageUrl , .u58990440ce4e446788d91e3f02a21697 .centered-text-area { min-height: 80px; position: relative; } .u58990440ce4e446788d91e3f02a21697 , .u58990440ce4e446788d91e3f02a21697:hover , .u58990440ce4e446788d91e3f02a21697:visited , .u58990440ce4e446788d91e3f02a21697:active { border:0!important; } .u58990440ce4e446788d91e3f02a21697 .clearfix:after { content: ""; display: table; clear: both; } .u58990440ce4e446788d91e3f02a21697 { display: block; transition: background-color 250ms; webkit-transition: background-color 250ms; width: 100%; opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #95A5A6; } .u58990440ce4e446788d91e3f02a21697:active , .u58990440ce4e446788d91e3f02a21697:hover { opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #2C3E50; } .u58990440ce4e446788d91e3f02a21697 .centered-text-area { width: 100%; position: relative ; } .u58990440ce4e446788d91e3f02a21697 .ctaText { border-bottom: 0 solid #fff; color: #2980B9; font-size: 16px; font-weight: bold; margin: 0; padding: 0; text-decoration: underline; } .u58990440ce4e446788d91e3f02a21697 .postTitle { color: #FFFFFF; font-size: 16px; font-weight: 600; margin: 0; padding: 0; width: 100%; } .u58990440ce4e446788d91e3f02a21697 .ctaButton { background-color: #7F8C8D!important; color: #2980B9; border: none; border-radius: 3px; box-shadow: none; font-size: 14px; font-weight: bold; line-height: 26px; moz-border-radius: 3px; text-align: center; text-decoration: none; text-shadow: none; width: 80px; min-height: 80px; background: url(https://artscolumbia.org/wp-content/plugins/intelly-related-posts/assets/images/simple-arrow.png)no-repeat; position: absolute; right: 0; top: 0; } .u58990440ce4e446788d91e3f02a21697:hover .ctaButton { background-color: #34495E!important; } .u58990440ce4e446788d91e3f02a21697 .centered-text { display: table; height: 80px; padding-left : 18px; top: 0; } .u58990440ce4e446788d91e3f02a21697 .u58990440ce4e446788d91e3f02a21697-content { display: table-cell; margin: 0; padding: 0; padding-right: 108px; position: relative; vertical-align: middle; width: 100%; } .u58990440ce4e446788d91e3f02a21697:after { content: ""; display: block; clear: both; } READ: Observation of the Early Childhood Essay We will write a custom essay on Why Software Systems Fail specifically for you for only $16.38 $13.9/page Order now

Animal Studies and School Project Ideas

Animal Studies and School Project Ideas Animal projects and studies are important to understanding various biological processes in animals and even humans. Scientists study animals in order to learn ways to improve animal health for farm production, wildlife preservation, and human companionship. They also study animals to discover new methods to improve human health. Animal studies give us a better understanding of disease development and prevention, as well as standards for normal and abnormal behavior. The following animal project ideas introduce areas of animal studies that can be explored through experimentation. Since some science fairs may prohibit projects that involve animals, so be sure to get permission from your instructor before beginning any animal-based science project. Amphibian and Fish Project Ideas Does temperature affect tadpole growth?Do water pH levels affect tadpole growth?Does water temperature affect amphibian respiration?Does magnetism affect limb regeneration in newts?Does water temperature affect fish color?Does the size of a population of fish affect growth?Does music affect fish activity?Does the amount of light affect fish activity? Bird Project Ideas Which types of plants attract hummingbirds?What factors increase egg-laying in birds?Do different bird species prefer a particular color of bird seed?Do certain bird species prefer to eat in a group or alone?Do certain bird species prefer one type of habitat over another? Insect Project Ideas How does temperature affect the growth of butterflies? How does light affect ants?Do different colors attract or repel insects?How does pollution affect insects?How do insects adapt to pesticides?Do magnetic fields affect insects?Does soil acidity affect insects?Does color affect insect-eating habits?Does light or heat attract insects to lamps at night?Do insects behave differently in a larger population as opposed to a smaller population?What factors cause crickets to chirp more often?What substances do mosquitoes find attractive or repellent? Mammal Project Ideas Does light variation alter animal sleep habits?Do cats or dogs have better night vision?Does music affect an animals mood?Do bird sounds affect cat behavior?Which animal sense has the greatest effect on short-term memory?Does animal saliva have antimicrobial properties?Does colored water affect animal drinking habits? Animal Information and Resources For additional information about animals, see: 10 Fascinating Animal Facts: Discover several wondrous and fascinating facts about animalsTen Amazing Bioluminescent Organisms: Some organisms such as jellyfish have the ability to glow. The light emitted is due to a chemical reactionWhy Some Animals Play Dead: When faced with danger, some animals go into a catatonic state and appear to be dead to the world.Top 7 Bugs That Feed on Humans: There are a number of bugs that feed on humans. These bugs are resilient, gaining immunity to insecticides, and out for your blood.Common Animal Questions and Answers: Why do zebras have stripes? Why do some tigers have white coats? Find answers to these and other commonly asked questions about animals.The Worlds Fastest Animals: What are the fastest animals on the planet? These swift animals reach amazing speeds on land, in the air, and in the ocean. Science Experiments and Models Performing science experiments and constructing models are fun and exciting ways to learn about science. Try making a model of the lungs or a DNA model using candy. You can also discover how to extract DNA from a banana or get ideas on how to use plants in experiments.

The Difference Between Purines and Pyrimidines

The Difference Between Purines and Pyrimidines Purines and pyrimidines are two types of aromatic heterocyclic organic compounds. In other words, they are ring structures (aromatic) that contain nitrogen as well as carbon in the rings (heterocyclic). Both purines and pyrimidines are similar to the chemical structure of the organic molecule pyridine (C5H5N). Pyridine, in turn, is related to benzene (C6H6), except one of the carbon atoms is replaced by a nitrogen atom. Purines and pyrimidines are important molecules in organic chemistry and biochemistry because they are the basis for other molecules (e.g., caffeine, theobromine, theophylline, thiamine) and because they are key components of the nucleic acids dexoyribonucleic acid (DNA) and ribonucleic acid (RNA). Pyrimidines A pyrimidine is an organic ring consisting of six atoms: 4 carbon atoms and 2 nitrogen atoms. The nitrogen atoms are placed in the 1 and 3 positions around the ring. Atoms or groups attached to this ring distinguish pyrimidines, which include cytosine, thymine, uracil, thiamine (vitamin B1), uric acid, and barbituates. Pyrimidines function in DNA and RNA, cell signaling, energy storage (as phosphates),  enzyme regulation, and to make protein and starch. Purines A purine contains a pyrimidine ring fused with an imidazole ring (a five-member ring with two non-adjacent nitrogen atoms). This two-ringed structure has nine atoms forming the ring: 5 carbon atoms and 4 nitrogen atoms. Different purines are distinguished by the atoms or functional groups attached to the rings. Purines are the most widely occurring heterocyclic molecules that contain nitrogen. They are abundant in meat, fish, beans, peas, and grains. Examples of purines include caffeine, xanthine, hypoxanthine, uric acid, theobromine, and the nitrogenous bases adenine and guanine. Purines serve much the same function as pyrimidines in organisms. They are part of DNA and RNA, cell signaling, energy storage, and enzyme regulation. The molecules are used to make starch and proteins. Bonding Between Purines and Pyrimidines While purines and pyrimidines include molecules that are active on their own (as in drugs and vitamins), they also form hydrogen bonds between each other to link the two strands of the DNA double helix and to form complementary molecules between DNA and RNA. In DNA, the purine adenine bonds to the pyrimidine thymine and the purine guanine bonds to the pyrimidine cytosine. In RNA, adenine bonds to uracil and guanine still bonds with cytosine. Approximately equal amounts of purines and pyrimidines are required to form either DNA or RNA. Its worth noting there are exceptions to the classic Watson-Crick base pairs. In both DNA and RNA, other configurations occur, most often involving methylated pyrimidines. These are called wobble pairings. Comparing and Contrasting Purines and Pyrimidines The purines and pyrimidines both consist of heterocyclic rings. Together, the two sets of compounds make up the nitrogenous bases. Yet, there are distinct differences between the molecules. Obviously, because purines consist of two rings rather than one, they have a higher molecular weight. The ring structure also affects the melting points and solubility  of the purified compounds. The human body synthesizes (anabolism) and breaks down (catabolism) the molecules differently. The end product of purine catabolism is uric acid, while the end products of pyrimidine catabolism are ammonia and carbon dioxide. The body does not make the two molecules in the same location, either. Purines are synthesized primarily in the liver, while a variety of tissues make pyrimidines. Here is a summary of the essential facts about purines and pyrimidines: Purine Pyrimidine Structure Double ring (one is a pyrimidine) Single ring Chemical Formula C5H4N4 C4H4N2 Nitrogenous Bases Adenine, guanine Cytosine, uracil, thymine Uses DNA, RNA, vitamins, drugs (e.g., barbituates), energy storage, protein and starch synthesis, cell signaling, enzyme regulation DNA, RNA, drugs (e.g., stimulants), energy storage, protein and starch synthesis, enzyme regulation, cell signaling Melting Point 214 C (417 F) 20 to 22 C (68 to 72 F) Molar Mass 120.115 gmol1 80.088 g mol1 Solubility (Water) 500 g/L Miscible Biosynthesis Liver Various tissues Catabolism Product Uric acid Ammonia and carbon dioxide Sources Carey, Francis A. (2008). Organic Chemistry (6th ed.). Mc Graw Hill. ISBN 0072828374.Guyton, Arthur C. (2006). Textbook of Medical Physiology. Philadelphia, PA: Elsevier. p. 37. ISBN 978-0-7216-0240-0.Joule, John A.; Mills, Keith, eds. (2010). Heterocyclic Chemistry (5th ed.). Oxford: Wiley. ISBN 978-1-405-13300-5.Nelson, David L. and Michael M Cox (2008). Lehninger Principles of Biochemistry (5th ed.). W.H. Freeman and Company. p. 272. ISBN 071677108X.Soukup, Garrett A. (2003). Nucleic Acids: General Properties. eLS. American Cancer Society. doi:10.1038/npg.els.0001335 ISBN 9780470015902.

Facilities Engineering Coursework Example | Topics and Well Written Essays - 3000 words

Facilities Engineering - Coursework Example Here are the CPR results obtained for oil and gas exploration: Figure 1: CPR results of Gas and Oil extracted from Gazelle Well Major products extracted out of the oilfield at Gazelle are liquefied petroleum gas, gasoline, diesel fuel, fuel oils, lubricating oils, paraffin wax, sulfur. Question: Prepare flow schemes showing the architecture of the layout and of the main components used from the wellhead to the point of export for all option. The architectural layout of the Gazelle offshore oilfield is shown below with all the processing units and their respective processing cycles. This is a very large operating unit with extensively large piping layout with fluid streams running along. Crude oil is first passed through an oil production unit which provides the pre-processed oil to the oil storage tank from where it is delivered to the processing plant through a piping system. Here is the detailed flow diagram of all the processes taking place along their sequential flows: Figure 2: Flow Diagram of Gazelle Oilfield with components used in Oil Production Gazelle oilfield is a field that requires extensive production as well as operational refurbishments but even then it is above working above case base oil producing offshore refineries. This oil production unit involves a number of operating units that work extensively for long hours to provide quality product in economical rates with least water cuts. Following is an exhaustive list of components that work as a part of oil refinery at Gazelle(Snow, 2010, Gordon, 2012). De-salter unit is just provided at the inlet of crude oil and is responsible for washing away all the salt from crude oil. Distillator: Crude oil from de-salter is then passed through the distillatory unit which distills the crude oil into fractions. Second stage of distillation is also incorporated just after this by making use vacuum distillation unit which is responsible for the distillation of the left over components of crude oil which were not fractioned by simple distillatory. Hydrotreater: all fractions of the crude oil are then hydrogenated according to their requirements and this process is performed for removing sulfur contents from the oil fractions. Catalytic Reformer: it is used to reform the low grade oil fractions into high grade products like converting gasoline to a higher degree of octane level. While reforming the oil fractions excess amount of hydrogen is produced as a by-product of the process. Fluid Catalytic Cracker: this catalytic cracker is specialized in converting only liquid oil fractions to higher grade of oil. The process of converting gasoline to hi-octane is processed there. Hydrocracker: hydrocracker then takes the oil fractions and hydrogenizes them in order to upgrade the fractions. Visbreaking: the oil fractions that are needed to be degraded to lower order fractions are then passed through visbreaking unit Coking unit: this unit is specialized in carbonizing the heavy oil components of the fractions in order to produce gasoline. This helps in converting maximum oil fractions into consumable products. Alkylation: this unit is specialized in converting low grade molecules to higher ones and hence improving the quality of gasoline. Dimerization: the process of dimerization is performed in order to hydrogenate the gasoline products. Isomerization unit: This unit is specia

Fanon's Fact of Blackness Essay Example | Topics and Well Written Essays - 1250 words

Fanon's Fact of Blackness - Essay Example The black man has been given two frames of reference within which he has placed himself, these are: his metaphysics and his customs. The black man does not know the moment that his inferiority appears, it is part of him. The black man has an overbearing burden of being always conscious of his body. This reaction is almost automatic as noted in the text. Several laboratories have for years tried to produce a serum for â€Å"degenerification†; â€Å"with all the earnestness in the world, laboratories have sterilized their test tubes, checked their scales, and embarked on researches that might make it possible for the miserable Negro to whiten himself and thus to throw off the burden of that corporel malediction† (Fanon 111). When he passes and hears â€Å"Look, a Negro!† he is a bit disturbed but only manages a forced smile to hide his humiliation. He hears â€Å"Look, a Negro!† again; he becomes angry but does not show it. When he hears it again, he no long er can hide his indignation and all his efforts to laugh himself to tears are fruitless since he cannot do so. His anger wells up inside him more (Fanon 112). The black man can not continue laughing because he has learnt from legends, stories, history and historicity that, this is the reality. In the train, no one wants to sit near him. They sit two or three spaces away from him. When he moves towards the other person, the other moves away and â€Å"disappears.† The white man feels â€Å"nausea† when he is in the proximity of the black man. Since the black man feels responsibility for his body, race and ancestors, he subjects himself to an objective examination, this is when he discovers his â€Å"blackness† and ethnic characteristic; he is weighed down by what he discovered and among them are cannibalism, fetichism, intellectual deficiency and above all; â€Å"Sho good eatin’† (Fanon 112). Having been completely â€Å"dislocated† and unable to cope with the white man, he forces himself to move away from his own presence and turns himself into an object. Having rejected his conscience and emotions from being seered with a hot rod, he accepts his fate as it comes since he wants to be a man and nothing else. This helps him to be at peace with himself by accepting himself for who he is; â€Å"I was the grandson of slaves in exactly the same way in which president Lebrun was the grandson of tax-paying, hard-working peasants. In the main, the panic soon vanished† (Fanon 113). Everyone pretends to be friendly while pointing out the fact that they are not racist, nor do they approve of color segregation. The black man has noticed with great discomfort that they always mention his color when they say that they shall not treat him differently because of his color, or that it is not because of his color that the black man is less intelligent than the white folks! When they find fault in the black man, they always try to h ide behind the phrase â€Å"it is not because you are black.† In reality, it is the only reason. It is not surprising that the black man is utterly misunderstood because when he shivers with cold, the white boy thinks that the black man is â€Å"quivering with rage† (114). In this racist society, the black man experiences his being through others. Despite his efforts to forget and forgive the hostility of the white man, and to live in peace and harmony with the other, his â€Å"message† is flung back to him (115). He then decides to fight back with

Drivers For Internationalization In Aerospace Management Essay

Drivers For Internationalization In Aerospace Management Essay The papers in this portfolio are all related to the strategic decisions that corporate organizations make in order to expand their share of the ever-growing global market, while ensuring that their competitors are not able to replicate their formula for success. Three of the papers discuss specific companies-Tesco, Rolls-Royce, Carrefour and Wal-Mart-thus giving the impression of a mini case study on how these global players strategize their way into market domination and superior firm performance. The third and final paper is a general discussion on George Yips model on internationalization drivers as these are applied in the civil aerospace engine manufacturing and the global grocery retailing industries. Students, scholars and practitioners alike will benefit from the lessons and analyses made in these papers because they show a thoughtful and realistic look into the workings of different corporate organizations while utilizing different business concepts. At the end of the day, this portfolio is designed to show the students ability to comprehend and analyze practical business dilemmas in light of existing theory. Drivers for internationalization George Yip proposed his model of the drivers for the growth of international strategy among corporate organizations. He introduced four main categories of drivers that were key in determining the extent of globalization within a particular industry. These are: Market globalization drivers Cost globalization drivers Government globalization drivers Competitive globalization drivers A company that exhibits less of these drivers is characterized as being local in nature, and conversely a company with a higher number of the drivers are becoming more global both in outlook and in operation. These drivers are not stand-alone, however, because they in fact influence on another in a cycle that determines a corporate organizations readiness to join the ranks of global companies. Stated otherwise, these internationalization drivers are governed by four different factors: technology, social and demographic considerations, politics and legislation, and economic and political considerations. All in all, should a company wish to transform its operations from that of a local industry to an international one, it should pay attention to the different factors that can make or break its ability to participate actively in the global market. While there are of course other factors that may influence a companys eventual success in going global, Yips model gives us a simplified and practical view of what it would take for a company to launch itself into the global playing field and claim its share of global consumers. Different industries and different corporate organizations vary greatly in their capacity for globalization, especially because the nature of the products/services they offer as well as the consumers who avail of them are vastly distinct from one another. Let us compare the global grocery retailing industry and the civil aerospace engine manufacturing industry as an example. We can compare the two in this manner: Global grocery retailing industry Civil aerospace engine manufacturing industry Market driver High Low Cost driver High High Government High Low Competitive High High Countries that have the most advantageous combination of as many drivers as possible are preferred by global companies, as a market for their products/services, as a home base or both. As we can see from the table above, the global retail industry actually has better potential for pushing a global strategy. This is evidenced by the relatively recent entry of new global grocery retailing brands such as Wal-Mart into previously untapped markets like China. Because of the high tendency for globalization, other retail companies are also beginning to look in to the possibility of expanding their business overseas in order to benefit from a bigger customer base. Carrefour, Wal-Mart and the Chinese market The entry of big international players in the Chinese local market in recent years has shown that China is the new gold rush for global companies looking to expand their share of the market. The global grocery retailing industry is just one of the many business sectors that have come to China to make the most out of the millions of consumers who will avail of their products and services. The bid to make China the next biggest market for the global retail industry started in 1992 when the country opened up its retail industry to foreign investors like Carrefour and Wal-Mart. Carrefour entered the market three years later by opening a partnership with a Chinese management consulting firm, creating an entity called Jia Chuang. While other companies treated the Chinese market as one big bloc of consumers, Carrefour looked considered it to be composed of many smaller markets. It opted to create regional offices which were in charge of the expansion programs for different areas of the country, instead of having a centralized national operations network. Carrefour continues to carry out its expansion strategy by depending on local distributors, who supervise the delivery of their products straight to the stores from the regional centres. The company believes that flexibility is a priority consideration especially when operating in a relatively new market. The cost of development is lower because Carrefour is able to build its network store by store while keeping issues about uniformity of service and quality control in check. As for Wal-Mart, they see the challenges of the Chinese retail market differently. Unlike Carrefour, Wal-Mart is putting its investments on a centralized distribution system that is headquartered in Kengzian. The new centre boasts of a 40,000 square meter facility that has been created to handle simultaneous deliveries with up to 70 bays. But like Carrefour, Wal-Mart has also entered the Chinese domestic market by partnering with a local firm, a Taiwanese retail firm named Trust-Mart. Wal-Marts emphasis on back-end operations is almost the exact opposite of Carrefours customer-first strategy, although the latter seems to be on the upper hand in terms of actual market share and profitability. However, at some point Carrefour will also need to pay attention to its back-end to maximize the strong dynamics among its stores. Its current strategy is working well for Chinas market environment but new developments will have to be introduced in the future. No global retailer has yet launched an all-out expansion into China without creating a joint venture with a local company, which is a strategy that enables them to ease slowly but surely into the market instead of going in without a clue as to how the market actually works from the inside. However, it would be more disadvantageous for a global company not to try breaking into the Chinese business scene. The market is rich with millions and millions of consumers who are only too willing to try new the products and services that have suddenly become available to them thanks to the opening up of the market. Care must be made in making these new foreign financial investments work in order to ensure that the companies will see good returns on their investments. Companies must not be deluded by the promise of a huge new market and fall behind their usual standards for doing business. Tescos core strategies and VMO Tesco is one of the leaders in the global retailing industry. The company started in the United Kingdom in the late 1920s and has since grown to be one of the most robust and successful supermarket companies in the world today. Tescos core strategy is founded on their desire to attract and maintain customers who will become their lifetime partners. The company espouses the belief that their corporate success is dependent on their ability to meet the demands of people-both the people who work for them and the people who shop with them. Tescos two-pronged approach misses out on no opportunity to improve not only their service and products, but also their international relationship with their staff. This is reflective of the current thinking among corporate organizations today that a companys human capital is more than just another factor of production-they are in fact the backbone of a company and they make it possible for the corporate strategies to be carried out effectively. Paauwe and Boselie (2002) point out that the emergence of such a breed of HR management has been brought about by the fact that human capital is now seen as a source of competitive advantage. As for Tescos commitment to their customers, the company is firmly rooted in the belief that going the extra mile to satisfy their shoppers needs and requirements will go a long way towards ensuring their loyalty to Tesco. Loyalty is key to maintaining and expanding Tescos share in the retail market. If Tesco can give a customer superior service, then there are higher chances that that customer will keep shopping only at Tesco. But before Tesco can be first to meet their customers needs, they embark on a focused and in-depth study of their shoppers in order to anticipate what they require. Tesco employs what they call the Every Little Bit Helps strategy to ensure that they know exactly what their shoppers and their employees want. Tesco has designed five core business purposes: Be a successful international retailer Grow the core UK business Be equally strong in the food and non-food sectors Develop competitive retailing services Put the community at the core of all business activities. The Every Little Bit Helps strategy is Tescos way of translating these core objectives into actual strategies to help the company achieve its organizational goals. Without the concurrence of both strategy and purpose to guide a corporate organization, especially a global one like Tesco, there will be little chance for the company to have a clear direction of where it wants to go and how to go there. The core strategy and core purposes of Tesco are a way for the company to articulate what it wants to achieve within a given timeframe, as well as crafting the necessary steps to accomplish the goals that it had set for itself. As for Tesco, the company is imbued with the lesson that no organization will progress without considering the needs of its customers and its employees, so their approach is always to seek what is best for both in order to make the company number one. Strategic alliances and Rolls-Royce No man is an island-and even in businesses, this clichà © rings true today. Some organizations, particularly small-scale ones or those that have only just started doing business, may be better off finding their own niche in todays complex market, but there may come a time when they will have to form significant partnerships with other businesses in order to flourish and achieve sustained growth. The current state of the global business landscape today has forced organizations to come up with more creative ways of surviving and keeping ahead of their competitors. Some of the more important aspects that most companies today are focusing on to improve their overall performance are enhancing their brand identity, connecting with customers and attracting competent and highly-skilled workers (Isidro, 2000). Moreover, todays corporate managers are also facing a highly competitive environment that is increasingly complex, globally cantered, and technologically uncertain where there is a critical need for dynamic, flexible, and proactive responses (Miles, Preece, and Baetz, 1999). It is no longer enough to emphasize on creating and opportunities on their own, because independence also has its drawbacks. As a result of the various pressures that companies are facing, there is now an increased tendency among them to favour forging strategic partnerships and alliances as a viable business option. Elmut and Kathawala (2001) are also of the opinion that strategic alliances among corporate organizations are one of the most recent trends in the business community that have made it possible for companies to stay afloat despite serious drawbacks and difficulties. In the case of Rolls-Royce, the company has entered into almost 30 separate partnerships with different firms all over the world to help expand its share of the global market and build on its knowledge and technology base. Of the four reasons that Elmut and Kathawala (2001) outlined for the emergence of strategic alliances, it appears that there are two primary reasons for why Rolls-Royce has chosen to partner with different firms. For one thing, the company stands to gain from such partnership in terms of entering new markets with which it is unfamiliar. Brokering a deal with local corporations allows Rolls-Royce to expand its market while at the same time benefiting from the expertise of an old-timer in the market. Secondly, Rolls-Royce is also into strategic partnerships in order to obtain new technology and best quality at the cheapest cost. The company has four business divisions, all of which need intense research and development funding. Instead of going through their own R and D cycle, Rolls-Royce can share their knowledge and technology with their strategic partners at a much lower cost, thus ensuring that each division is well-maintained but is not draining the companys resources for continuous R and D. While Rolls-Royce can actually provide the funding for its own R and D, it is more cost-efficient for the company to trade information with its partners and make the product or service immediately available in the market. It must be noted, however, that it is not just Rolls-Royce who stands to reap all the wonderful benefits from the strategic alliance. Their partners also take advantage of the Rolls-Royce brand name and the companys existing network of contacts, suppliers and customers, giving the other partner a fair competitive advantage over its competitors in the local market. Strategic alliances are all about creating good working relationships with other companies in the industry and pooling together resources for the mutual benefit of the partners.

Compensation Consultants Essay

Compensation consultants are now becoming a popular tool to assist company in managing their compensation program and corporate governance strategies. However, there are both pros and cons in using compensation consultants. On one hand, there are some clear benefits; firstly, compensation consultants can provide expert knowledge, for example, insight and advice on trends in executive compensation, an assessment of executive compensation relative to executive performance; and insight and advice on the level and mix of pay and benefits (Conyon, 2007). Although, compensation consultants are viewed as external third parties providing solutions of optimal efficient managerial compensation contracts to align the benefits of both the employee and employer in the most fair and unbiased way. They have the ability to help the firm maximize shareholder’s value by designing compensation schemes that more closely align the interests of managers with shareholders since they can bring breadth and depth of experienced from handling similar problems and benchmarking comparable (peer group) firms especially when there is high information asymmetry between different parties. Other benefits include cost reduction in recruiting/rewarding process and efficient allocation of resources by taking the tasks away from human resource, compensation committee and shareholders who may not have the knowledge and experience in determining senior executive pay package. On the other hand, there are some drawbacks in hiring compensation consultants. Firstly, compensation consultants face potential conflicts of interest that can lead to higher recommended levels of CEO pay, including the desires to cross-sell services and to secure repeat business. Evidence shows that US CEOs receive about 18% more total compensation, and Canadian CEOs receive about 33% more, when their executive compensation consultant also provides other services to the firm (Murphy & Sandino, 2010). They are more likely to help executives by pushing for higher compensations in hope of being rewarded with more consultants services with the company as such firms that hire compensation consultants are more likely to have higher CEO compensation levels than those that have not hired a consultant (Voulgaris, et al. 2010) (Goh & Gupta, 2010). However, contrary to the study of Murphy & Sandino 2010, some scholars found that the potential conflict of interest between the firm and consultant is not a primary driver of excessive CEO pay. Their explanation is that opposing incentives to maintain consultants’ credibility or safeguards put in place by compensation committees limit actions taken with regard to cross-selling incentives (Cadman, et al. , 2010). Secondly, consultant fees can be substantial; thus, the company should weigh the costs/benefits to determine whether hiring a consultant is appropriate. Thus, in my view, compensation consultants may not be part of agency problems but rather a solution to the problem of designing an optimal executive pay contract that aligns the interests of both the employee and employer if the firm can strengthen and promote transparency in its hiring process to maximize shareholder’s values.