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Production of Pulp and Paper, 2003.
The papermaking process from a chemical engineering piont of view.
4,430 words (approx. 17.7 pages), 12 sources, MLA, $ 116.95
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Abstract
This paper provides a detailed and in-depth explanation about the papermaking process. It explains the chemical process of how the materials are transformed from wood to paper pulp. A history of this practice is also discussed and and examination of how it has developed over history. The paper looks at the current big players in the market and includes many charts and tables.
From the Paper
"Papermaking originated in China in around 105 A.D. and its creation is generally attributed to a court official called Cai Lun. The first paper was made from a mixture of nonwood fibers, including mulberry bark. Knowledge of papermaking then spread to the Middle East through central Asia and reached Europe in the 12th century. From there, that knowledge later spread to North America and eventually to the rest of the world. A wide variety of fibers have been used to make paper, but in the years leading up to the 18th century, relatively large quantities were being made from linen rags. At that time, each individual sheet was made separately. The papermaker would dip a mesh known as a forming screen into a vat containing a solution of water and fiber (the stock). A sheet of paper would then be formed on the screen solely through the natural bonding of the fibers as the screen was lifted out of the water/fiber solution and drained. The sheet was then pressed and dried. Traditional papermakers in Japan and Taiwan, as well as papermaking craftspeople in other countries, still make paper using this time-honored process."
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Heating Problems During Re-entry of Space Shuttles, 2003.
Analysis of space shuttle re-entries, focusing on the problems encountered by the Columbia.
791 words (approx. 3.2 pages), 5 sources, MLA, $ 28.95
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Abstract
As the space shuttle Columbia began its re-entry into Earth?s atmosphere on February 1, 2003, it began to break up. While the exact cause of the shuttle break up is still being investigated, there are many theories being considered, many of which have to do with heating tiles under the shuttle. The paper examines the process of an air-shuttle's re-entry into the atmosphere and shows where things could have gone wrong with Columbia.
From the Paper
"In the final stage, the shuttle approaches the upper atmosphere and enters the ionization blackout. In the ionization blackout, hot ionized gases of the atmosphere surround the shuttle. This prevents radio communication with mission control for the about twelve minutes. At this point the shuttle is traveling at 17,000 mph. As the shuttle collides with air molecules, friction is generated which leads to surface temperatures of around 3000 F. The steep angle of re-entry ensures that most of the aerodynamic heating is directed towards the underside of the shuttle where the heat resistant tiles offer the greatest amount of protection. As the atmosphere thickens, the shuttle's thrusters are eventually switched off, at which point the shuttle?s aerodynamic flight features kick in, and it can be flown like an airplane."
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Rapid Prototyping, 2002.
An introduction to the concept of rapid prototyping in industry.
3,703 words (approx. 14.8 pages), 8 sources, MLA, $ 102.95
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Abstract
This paper examines the issue of rapid prototyping in which is one attempt at expediting the process of prototyping and combines computer-aided design (CAD) with computer aided manufacturing (CAM) to produce prototypes faster than traditional methods. It looks at how companies rely on having efficient and rapid development cycles in order to remain profitable.
Outline
Introduction
Importance of Topic
Description of Rapid Prototyping
Approaches to Rapid Prototyping
Benefits of Rapid Prototyping
Drawbacks to Rapid Prototyping
Industries and Businesses Using Rapid Prototyping
Outlook
Conclusion
From the Paper
"Prototypes have long been a valuable part of manufacturing and machining processes. The simplest form of a prototype provides a non-working model of the finished product that allows possible design flaws to be noted and corrected prior to investing in an entire production run. Materials, dimensions, production difficulties and other aspects of a product can be evaluated in a "real-world" environment prior to moving ahead with a new product. The benefits of prototyping are that companies are able to evaluate products without necessarily committing to them, and designs can be optimized in small lots so that resources are not spent inefficiently ("The Solid," 2001)."
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Engineer Responsibility, 2002.
This paper discusses that the consideration of the social responsibilities of engineers involves the concept of introducing normative values into the generally positivist practice of engineering.
2,155 words (approx. 8.6 pages), 9 sources, APA, $ 67.95
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Abstract
This paper explains that the introduction of normative values into the practice of engineering requires the application of systems of ethics and ethical principles to the process of engineering practice and engineering management. The author believes that ethical principles create a framework that permits the anticipation of conflict in relation to proposed actions or decisions in a variety of situations. The author says that utilitarianism and deontology tend to command the greatest level of attention in ethical considerations involving the business and the economy.
From the Paper
"Autonomy requires that an engineer be independent in action and decision-making and accept responsibility for her or his actions and the consequences of those actions. Autonomy, however, may also be interpreted to mean that others also have the right of self-determination concerning actions that affect their lives. The ethical principle of autonomy is especially applicable to those cases where the autonomous rights conflict with one another."
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Micro Miniaturization, 2002.
An examination of the technology, which shrinks the size of components necessary to implement pressure transducers, and how it can be applied to other domains.
4,684 words (approx. 18.7 pages), 20 sources, MLA, $ 120.95
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Abstract
This paper defines the technology of micro miniaturization which was conceived in the electronics industry. It discusses the status of ongoing research specifically oriented to fabrication, performance, and application of micro sensors and their use for heat transfer and fluid flow measurements. It looks at how the application of this technology to other domains outside of the electronics industry has become known as ?surface machining,? and has emerged during the last thirty (30) years as a viable technology.
From the Paper
"Fabrication capabilities have continued to grow over the last twenty years and have produced a large number of actuator assembly combinations that include miniature motors, tweezers, accelerometers, and pressure sensors. It is now feasible to consider using micro machining technology to fabricate chemical instruments and even miniature chemical laboratories (Ramsey, 1997). Surface machined pressure sensors (Lin, 1998), have been designed, optimized and fabricated. Polysilicon diaphragms with thicknesses in the range of two micro microns, have been manufactured by utilizing Low Pressure Chemical Vapor Deposition (LPCVD)and as such form the core components in micro pressure transducers. The diaphragms so generated stand atop micro vacuum cavities that are constructed by a specially designed, vacuum sealant process. Thus pressure changes cause a deflection of the diaphragm, the magnitudes of which are detected by using built-in piece resistive elements that are positioned on the surface of the diaphragms. Both square and circular-shaped sensors with nominal diameters in the range of 100 microns have been fabricated and tested. Optimized designs that include position orientation and length of the piece resistive elements have been analyzed. The attendant fabrication process is completely compatible with integrated circuit processing techniques in use today. Consequently, using stable technology, today, microelectronic structures can be fully integrated with micro sensors to create micro scale mechatronics systems."
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MESFETs, 2002.
A technical look at a specific type of transistor called a MESFET.
1,833 words (approx. 7.3 pages), 9 sources, APA, $ 58.95
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Abstract
A transistor is a device used for controlling one electrical signal with another. The name "transistor" came from combining the words "transfer" and "resistor" and the name tells how the device works. This paper describes one type of transistor called a Metal Semiconductor Field Effect Transistor (MESFET), which is made by building layers on top of each other and doping the semiconductor material to a profile. The paper includes diagrams and figures.
From the Paper
"While MESFET integrated circuits have become accepted in many high frequency applications, they have certain limitations. For power amplifiers used in digital systems it is important to have a linear signal - one that is not distorted or altered when amplified (RF Micro Devices, 2000). GaAs MESFET devices cannot meet the high linearity performance standards without sacrificing other performance standards. Also, GaAs MESFET amplifiers usually require both a positive and a negative power supply, which requires the inclusion of additional components or circuitry, which means an increase in the size and complexity of the device. Also, the linear structure of GaAs MESFET devices hinders the ability to shrink the device and so enhance manufacturing yields and reduce costs."
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Construction Projects, 2002.
Compares the Golden Gate Bridge and the Eurotunnel to determine whether they were successful or unsuccessful construction projects.
3,668 words (approx. 14.7 pages), 15 sources, APA, $ 101.95
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Abstract
When considering the variables that influence the outcome of a major construction project, it is important to recognize that a project is nothing more or nothing less than a one-time job that has definite starting and ending points, clearly defined objectives, scope and a budget. In order to determine what distinguishes a successful major construction project from one which fails, two projects are compared in this paper. The first is the Golden Gate Bridge, completed in 1937, under conditions which would try the patience and test the competencies of its designers, builders, and sponsors. The second construction project is the Eurotunnel, also known as the Chunnel, the underwater tunnel linking England and France. Completed in the early 1990s, the Chunnel stands as an excellent example of a major construction project which was ultimately successful in the sense of structural integrity and to an extent, customer satisfaction, but a miserable failure in terms of scheduling and massive budgetary or cost overruns.
From the Paper
"In 1989, Andrew Phillips (1989) reported on major problems which were seriously disrupting the completion of the project. Initially, the engineers and managers faced technical obstacles that delayed start-up and construction of the project. Though these obstacles were overcome, soaring costs had added approximately $1.9 billion to the cost of the tunnel itself. To make matters worse, Phillips (1989) maintains that the estimated costs of a planned high-speed rail link between London and the Chunnel?s English terminal near Folkestone, more than doubled. In 1987, the company building the tunnel put the total cost of the project at $9.1 billion - this was raised to $10.2 billion in 1988, and in 1989, analysts predicted that the cost of the Chunnel would ultimately reach $11 billion."
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Tang Engineering Inc., 2002.
A decision analysis case for Tang Engineering Inc., involving the feasibility of the production of a component.
1,347 words (approx. 5.4 pages), 3 sources, MLA, $ 45.95
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Abstract
This paper examines how Tang Engineering, Inc. has been offered a potentially profitably contract with a major automobile manufacturer involving the production of a new engine component for Toyda Motor Company. It looks at how Tang Engineering has already conducted an experiment involving the manufacture of prototypes of the engine component that would be produced under the contract and attempts to determine the feasibility of the production of the engine component by the company within the mean unit production time constraint.
From the Paper
"The key determining factors in the ability of the company to manufacture the engine component within the constraint of a mean unit production time of < 1.5 minutes are lathe speed and drill speed. Tang Engineering experimented with three different lathe speed setting and three different drill speed settings. The matching of lathe speed settings and drill speed settings in the production experiment resulted in five different manufacturing process states, as follows: State 1 (lathe speed setting 1 and drill speed setting 1); State 2 (lathe speed setting 1 and drill speed setting 3); State 3 (lathe speed setting 2 and drill speed setting 2); State 4 (lathe speed setting 3 and drill speed setting 1; and State 5 (lathe speed setting 3 and drill speed setting 3).
Production data were collected in relation to each of the experimental production process states. The data collected were (1) the number of engine components produced in a batch run and (2) the overall time required for the completion of each batch run. These data were analyzed to assess the feasibility of Tang Engineering?s ability to manufacture the engine components within the constraint of a mean unit production time of < 1.5 minutes."
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The Tube, 2002.
A history of the London underground system.
1,004 words (approx. 4.0 pages), 2 sources, MLA, $ 35.95
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Abstract
This paper looks at the world's oldest subway in London and how it followed the development of the above-ground railway system in England and then went underground for a rapid transit system for the city long before the term "rapid transit" had been devised. It outlines the continuous growth and expansion of the network from the first underground railway which opened by the Metropolitan Railway Company on 10th January 1863.
From the Paper
"The act of tunneling under the Thames required a different engineering approach from the cut-and-cover method. Building this part of the system involved deep-level excavation at the foot of vertical shafts and was similar to coal mining. Since much of London is built on clay, and since clay is easy to excavate and tunnel through, work was completely relatively soon on the next significant step in the development of London's Underground railways--the twin-tunnel City and South London Railway, which ran for 5.2 km (3.25 miles) from King William Street in the City under the River Thames to Stockwell. This was intended to be a cable-hauled railway, but when it opened in 1890, it was the world's first deep-level electric railway. This and similar lines built since have since always been known as tube railways. The Waterloo & City Railway was also constructed under the Thames River and was opened in 1898. Two years later, the Central London Railway opened."
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Railroads in Southern Brazil, 2002.
Examines the role of railroads in the economic development of southern Brazil from 1875 to 1930.
1,778 words (approx. 7.1 pages), 12 sources, MLA, $ 57.95
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Abstract
Railroads were first constructed in southern Brazil to serve primarily as growing coffee production industry in S?o Paulo state. Railroad growth in the region, however, facilitated the growth and development of other economic activities such as communication and agriculture. In its early stages of development, Brazil's socioeconomic activities were separated. According to the paper, railroads developed in response to the needs of an agrarian economy but served also to support the development of industry in Southern Brazil. The paper argues that the railroad aided in the integration of the economies of the states in southern Brazil.
From the Paper
"According to Poppino, because of the economic ascendance of Southern Brazil from the late-nineteenth century through 1920, which was facilitated by railroad development, "the locus of political power shifted permanently to the South, where S?o Paulo became the economic heart of the country, and a new class of industrialists, drawn from immigrants and the land holding elite, competed with plantation owners for prestige and political influence. Railroads, thus, developed in response to the needs of an agrarian economy but served also to support the development of industry in Southern Brazil."
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Survivors of the Titanic, 2002.
This papers analyzes the events around the rescue of the approximately 700 of the Titanic's more than 2,200 passengers.
1,506 words (approx. 6.0 pages), 5 sources, MLA, $ 49.95
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Abstract
The paper looks at several sources, including first-hand accounts of survivors, to discover what were the events that led to the rescue of some passengers when the majority did not survive the sinking ship. The writer brings in several theories from the rescue of women and children only to the inability of non-English speakers to understand the full scope of the impending tragedy.
From the Paper
"On 10 April 1912, the American-owned British-operated White Star liner Titanic departed from the Irish port of Queenstown on her maiden voyage. She carried approximately 2,228 passengers and crew, including 1,697 men (12 years of age and older) and 528 women and children (Geller 8). Four days later, on April 14, 1912, the Titanic sank two hours and 40 minutes after striking an iceberg in the North Atlantic (Geller 8). Titanic was built in a period of history called the Edwardian Era in Britain, La Belle Epoque in France and the Gilded Age in America (Geller 13). The period was characterized by the Industrial Revolution, which helped fuel a change in the traditional society."
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Personal and Public Transport Systems, 2003.
A description and comparative analysis of the workings of different forms of modern transport.
2,655 words (approx. 10.6 pages), 13 sources, MLA, $ 79.95
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Abstract
This paper takes three different forms of transport, the aXcess car, the Millennium Train and the PRST-4 Mountain Bike and analyzes how they work together with comprehensive pictures and diagrams. For each method of transformation it gives an overview and looks at the workings of the wheels, frame, body and brakes. It then proceeds to compare and contrast the differences between the wheels, frame, body and brakes in the different modes of transport. It concludes with a look at the process of forming for bike and car tires.
From the Paper
"The forming of a polyurethane micro cellular bike tyre (such as Urethon?s tyres which are puncture proof and can be recycled) begins by metering a specially formulated liquid consisting of polyurethane, polyol and, isocyanate components in a high pressure-metering cylinder type polyurethane dispensing machine. The liquid then passes through an impingement chamber into a mould (a polyurethane elastomer, manufactured by casting a specially formulated polyurethane into different tyre sized aluminium moulds), which is designed to have different tread rings fitted, with nylon cord for reinforcement of the tyre pre fitted (the cord stops the tyre slipping from the wheel rim). The mould is then clamped to a centrifugal casting machine, which spins the moulds at between 200-400rpm."
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