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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Proposta para implementação de uma bancada dinamométrica automatizada para ensaios em tempo real de motores de combustão interna do ciclo Otto / Proposal for implementation of an automated dynamometric bench for tests in real time of internal combustion engines of the Otto cycle

Bezerra, Adriano Carlos Nogueira 05 May 2000 (has links)
Com o advento da crise do petróleo na década de 70, os motores, que antes eram calibrados para fornecer máximos torque e potência, após a crise passaram a ser calibrados de forma a fornecer consumo específico e emissões mínimos. A partir de então os motores passaram a ser ensaiados em bancadas dinamométricas que possuíam módulo para medição de emissões e que simulavam condições mais reais de tráfego, segundo um ciclo de ensaios preestabelecido. Este trabalho contém um levantamento bibliográfico sobre o instrumental, metodologias e procedimentos utilizados nos ensaios dinamométricos permanentes e dinâmicos e propõe a implementação de uma metodologia para realização de ensaios em tempo real controlado por computador. Traz também os resultados experimentais relativos à parte da metodologia que foi implementada. / With the advent of petroleum crisis in the 70\'s, engines, previously calibrated in order to supply maximum momentum and power, after the crisis they started being calibrated to supply minimum specific consumption and emissions. After this, engines started being tested in dynamometric benches equipped with emission measure modules and that simulate traffic conditions closer to reality, according to a prior emissions cycle. This work contain a bibliographic survey about instruments, methodologies and procedures used in the steady-state and dynamic dynamometric tests and proposes the implementation of a methodology to perform real time tests controlled computationally. It brings too experimental results related to the implemented methodology.
22

Motorcycyles emission factors determined by dynamometric tests using real road driving cycles.

Wang, Wen-Jeng 24 June 2002 (has links)
Because of the economic development of Taiwan, population gathering and the habit of people using transports, these considerations have made vehicle grow up fast. Vehicles emitted a large amount of pollutant that has caused many air pollution occasions. The motive of this study is to understand the motorcycle driving cycle, amount of pollutant and emission factor in four areas ¡VTaipei, Taichung, Kaoshiung and Pingtung. But it is very poor on concerning study in Taiwan. It is necessary to go on the concerning investigation and to establish the driving cycle and the actual emission factor of mobile source of Taiwan. The experiment includes two parts: one is regional driving pattern that is selected by factor analysis from samples; the other is to get the concentration of the pollutant and to calculate emission factors of the one by using Dynamometer. The pollutants are carbon monoxide (CO), total hydrocarbon (THC) and nitrogen oxides (NOX). In this study, the emission factors of motorcycles of the four areas are ¡§Taipei: CO 8.24 g/km, THC 2.53 g/km, NOX 0.12 g/km, CO2 55.98 g/km, Taichung: CO 7.81 g/km, THC 2.28 g/km, NOX 0.12 g/km, CO2 54.31 g/km, Kaoshiung: CO 6.53 g/km, THC 1.62 g/km, NOX 0.13 g/km, CO2 54.03 g/km, and Pingtung: CO 6.79 g/km, THC 1.63 g/km, NOX 0.13 g/km, CO2 41.42 g/km.
23

A Business Plan Feasibility Study of a new start up Company Base on the Project"Friction Material Derivatives Product"

Don, Jar-Shuen 17 July 2003 (has links)
Current world economy is impacted by the new and the old economy systems primarily due to high-tech software and hardware products that are constantly emerging to the market place. It has brought many innovations and high efficiencies to people¡¦s daily lives, e.g., the food, clothing, housing and transportation, etc. The influence of this evolution is potentially enormous and such evolution inspires people¡¦s confidence in the current Electronic Age. By reviewing the world¡¦s current economy, it appears that winner¡¦s economy system must rely on both the new and the old economy industries positively. In other words, the new economy has to be established on the foundation of stable traditional industries, and the old economy system must be improved and advanced with the help of the new technology. The basic reason is that the necessities of people¡¦s life are mostly supplied by the traditional industries from the old economy. As an island nation under the trend of the world¡¦s economy, Taiwan¡¦s new and old economy systems are required to be balanced in such a way that mutually one benefits the other. Because of this concern, the new government proposed a ¡§Green Silicon-Island Economical Development Project¡¨, and aggressively launched a ¡§Boosting Traditional Industry Plan¡¨ as well. By cultivating the traditional industries, the new economic technology can prosper accordingly. At this opportunistic juncture, Company A formulated a 5-year business plan to venture into a traditional industry: manufacturing of friction materials. The goal is to raise 4 million USD for starting up a production facility to manufacture and market a wide range of friction materials, in an effort to respond to the Government¡¦s call of boosting traditional industries. The main focuses of the proposed business are to build a solid manufacturing foundation on Taiwan, to market the products to the entire world, and to thrive the business to excellence with technology-based operation and management. The variety of friction materials is overwhelming. In terms of material composition, friction materials can be classified into the following four types: semi-metallic, sintered metallic, paper-based, and carbon fiber-based materials. This proposal explores key issues that are essential to the success of the production of all four types of friction materials. These key issues include: industry infrastructure, market size analysis, marketing strategies, operation networking, risk analysis, and core technical strength. Based on the above analysis, a 5-year financial planning is presented. Detailed analysis for the financial objectives on financial feasibility, cash flow, break-even point, and investment interests are also included. ¡K¡K¡K¡K¡K
24

Design of a rodent dynamometer

Dorsch, Angel M. January 2004 (has links)
Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains x, 122 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 78-83).
25

Evaluation of regulated emissions from heavy-duty diesel vehicles in the south coast air basin

Buffamonte, Thomas M. January 2003 (has links)
Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xii, 130 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 128-130).
26

Reverse engineering toolbox for pedagogical applications

Eid, Roy George 26 July 2012 (has links)
Reverse engineering, the technique of using different tools and methodology to recreate an object or machine, is increasingly used in academia to solidify theoretical concepts as part of the Kolb learning cycle. This thesis aims to aid the use of reverse engineering as a pedagogical tool by developing a toolbox that can be used by students, and professionals alike, to properly reverse engineer a mechanical or electro-mechanical product. The development begins with an analysis of House of Quality matrices, a design methodology tool used by the industry to relate customer needs to engineering metrics and specifications. After a consolidated list of metrics was developed, the appropriate tools to properly quantify said metrics were researched and documented. Finally, a toolbox was created, with set goals in mind, and applied in two case studies to analyze its performance. Simultaneously, a portable dynamometer was developed, documented, and tested, with the goal of creating an inexpensive and accessible tool to measure the power output of fractional horsepower DC and AC motors. / text
27

Performance reliability of Hong Kong elite rowers on the instrumented rowing ergometer

Fong, Hiu-fai., 方曉輝. January 2005 (has links)
published_or_final_version / Sports Science / Master / Master of Science in Sports Science
28

Day-to-day variability of and interrelationships between three anaerobic ergometer tests

Coggan, Andrew R. January 1983 (has links)
Knowledge of the magnitude of error in any test measure is important in judging the relative significance of that measure. The purpose of this investigation was to determine the day-to-day variability of, and interrelationships between, three anaerobic ergometer tests. The three tests examined were 30 second sprint bouts on a hydraulically-braked Fitron ergometer, 60 second sprint bouts using this same ergometer, and timed rides to exhaustion at a workload corresponding to 125% VO max. A total of twenty-seven subjects were assigned at random to perform four trials of one of these tests at one week intervals. An additional nine subjects performed one trial of each test. The mean coefficients of variation (CVQ SD x 100%) for the performance measures (mean tolerance power or ride time) were 5.4%. 5.47., and 5.37% for the 30 second, 60 second, and exhaustive tests respectively. The mean CV for 10 minute post blood lactate were 11.0%., 13.9%, and 11.0% for these same tests. The mean CV for peak torque and fatiguability were 6.7 and 10.37 for the 30 second test and 5.67% and 7.5% for the 60 second test. Mean power during the 30 second and 60 second tests were significantly related (r=0.69, p<0.05) l but these measures were not correlated with time to exhaustion. Exhaustive time was, however, significantly related to ten minute post exercise lactate concentration (r=0.91, p<0.01). It was concluded that the biological variability of anaerobic tests is similar in magnitude to that reported for measures of aerobic fitness (VO max). These data also indicate that the exhaustive test is a measure of relative, but not absolute, anaerobic tolerance.
29

The correlation among three hand srength [sic] measurement methods : hand dynamometer / Correlation among three hand strength measurement methods

Zhang, Jing January 1996 (has links)
The purpose of this study was to determine the correlation among three hand strength measurement methods: Hand dynamometer, MDD (Middle Digital Extension Isokinetic Dynamometer), and Cybex. Five students (2 males, 3 females) from Ball State University were asked to participate in this study. Both right and left lower arm data were collected from these subjects. A Cybex 340 (Lumax Cor.) was employed to determine wrist flexion and extension isokinetic peak torque, total work, and power at 30 degrees/second and 60 degrees/second. A MDD was used to determine third digit eccentric torque, work, and power. A hand dynamometer (Lafayette Instrument Co., Model 76618) was used to determine grip force. Pearson product moment correlation coefficients were used to determine correlation among these variables. Significant correlations were noted between isometric grip strength and isokinetic 30 and 60 degrees/second wrist flexion power, as well as between isometric grip strength and isokinetic 30 degrees/second wrist extensor power. The results of this study indicate there is very little relationship between the three clinically used measurement tools. / School of Physical Education
30

Determining optimal load for a constant-load cycle ergometer test relative to isotonic leg strength /

Wagner, Holly A., January 1992 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 66-69). Also available via the Internet.

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