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Jaiem, Karim. "High Speed Surrogate Vehicle Development." Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-69078.
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In order to keep down the costs in the automotive industry, it is decided to simulate dangerous scenarios that could occur in traffic, either virtually or by means of custom-made vehicles. This report addresses the development of a new type of surrogate vehicle called High Speed Surrogate Vehicle. This project has been carried out to prevent today's issues with surrogate vehicles and to enable an increase in testing efficiency, without increasing the risk of damaging test vehicles and injuries on personnel in an eventual collision.The report presents the surrogate vehicles area of use and its technical components. Reflection measurements have been made to compare radar characteristic between a real car and surrogate target and construction work has been carried out to manufacture fasteners for attaching the new High Speed Surrogate Vehicle. In the last phase of this degree project, final performance tests and collision tests were performed to verify its drive-and collision ability against test cars.
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Majeed, Baloch Abdul. "Development of high speed rail in Pakistan." Thesis, KTH, Trafik och logistik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-59699.
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Saff, David 1976. "Automatic continuous testing to speed software development." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/30096.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004.Includes bibliographical references (p. 147-152).
Continuous testing is a new feature for software development environments that uses excess cycles on a developer's workstation to continuously run regression tests in the background, providing rapid feedback about test failures as source code is edited. It is intended to reduce the time and energy required to keep code well-tested, and to prevent regression errors from persisting uncaught for long periods of time. The longer that regression errors are allowed to linger during development, the more time is wasted debugging and fixing them once they are discovered. By monitoring and measuring software projects, we estimate that the wasted time, consisting of this preventable extra fixing cost added to the time spent running tests and waiting for them to complete, accounts for 10-15% of total development time. We present a model of developer behavior that uses data from past projects to infer developer beliefs and predict behavior in new environments -in particular, when changing testing methodologies or tools to reduce wasted time. This model predicts that continuous testing would reduce wasted time by 92-98%, a substantial improvement over other approaches we evaluated, such as automatic test prioritization and changing manual test frequencies. A controlled human experiment indicates that student developers using continuous testing were three times more likely to complete a task before the deadline than those without, with no significant effect on time worked.
(cont.) Most participants found continuous testing to be useful and believed that it helped them write better code faster. 90% would recommend the tool to others. We show the first empirical evidence of a benefit from continuous compilation, a popular related feature. Continuous testing has been integrated into Emacs and Eclipse. We detail the functional and technical design of the Eclipse plug-in, which is publicly beta-released.
by David Saff.
S.M.
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Wong, Wing-sum Angela. "Possibility of the development of high speed train between Hong Kong and Mainland China." Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B31627699.
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Michel, Medhat. "Development of a medium speed road monitor vehicle." Thesis, University of Sunderland, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296031.
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White, David Allen. "Development of a high-speed rotating bar mechanism." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-12172008-063626/.
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Götze, David, and Susanne Haase. "Development of an Application for Managing Speed Skating Events." Thesis, Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-7536.
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This thesis provides insight in the further development of an application for managing speed skating events, based on the previous developed application by a group of students in fall 2010. The application was implemented for the Karlstad Speed Skating Club, which before used a program from the 90's. After finishing the implementation, all basic functionality requested by the Karlstad Speed Skating Club can be used for managing speed skating events. The first part of the thesis presents a short summary of our work, comparing what we wanted to implement and what we achieved. A short background on speed skating, the old system, developed by a group of students, and the project requirements are presented. An introduction to the used tools, languages, techniques and development processes is given along with details concerning the implementation of the requirements. Finally, the design of the new user interface is explained and the results are presented, containing an evaluation of the implementation, occured problems and what could be added in the future.
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Miller, Philip A. "High-speed rotor testing and spin-test facility development." Thesis, University of Ottawa (Canada), 1986. http://hdl.handle.net/10393/5492.
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Ono, Hitoshi 1969. "The role of high-speed rail in regional development." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/50349.
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Zafirakis, Zacharias. "Development of a Testing Assembly for Powertrain Speed Sensors." Thesis, KTH, Skolan för elektro- och systemteknik (EES), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-194222.
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Knowledge about the speed and the direction of the di˙erent shafts in the gearbox and the engine of trucks is becoming more and more important, especially as the industry moves towards autonomous vehicles. The most common way to measure these parame-ters today is by using inductive or Hall sensors. Testing and benchmarking these sensors has a large significance for heavy truck manufacturers such as Scania.In order to test these components, a rig assembly was constructed. In this project a LabVIEW program was developed for controlling the rig and gathering the required data. The aim of the rig was to try and simulate the behaviour of the components that are commonly measured in the gearbox or the engine, as well as use it for testing and benchmarking new rotational speed sensors. In order to achieve this, di˙erent processes were studied that cover certain working conditions in a Scania truck. The rig’s ability to follow these processes was then studied. In addition, a test case for inductive and Hall sensors was also presented.It is shown that the implemented solution for testing the sensors can be used for benchmarking di˙erent sensors and can be a useful tool for future sensor development at Scania. However, the rig with its current hardware was unable to closely replicate processes that are of interest. There are a lot of improvements that have to be made in order to properly simulate the behaviour of the powertrain components that are of interest for speed sensor applications.Information gällande hastigheten och riktningen på de olika axlarna i växellådan och motorn hos tunga fordon blir alltmer viktig, särskilt när fordonsindustrin går mot au-tonoma fordon. Det vanligaste sättet att mäta dessa parametrar idag är med induktiva-eller Hall-givare. Provning och utvärdering av dessa givare är därmed av stor betydelse för en fordonstillverkare som Scania.I detta projekt har en rigg designats för att testa dessa komponenter. Ett LabVIEW program har utvecklats för att styra riggen samt samla all relevant data med avseende på givarutveckling. Syftet med riggen var att simulera beteendet hos de komponenter i växellådan eller motorn som övervakas av dessa givare samt att använda riggen för att testa och jämföra nya varvtalsgivare. För att uppnå detta, undersöktes ett antal processer som täcker ett urval av driftsfall i en Scania lastbil. Riggens förmåga att återskapa dessa processer undersöktes. Utöver detta presenterades även ett testfall för induktiva- och Hall-givare.Den implementerade lösningen för provning av givare visas kunna användas för att jämföra olika givare och kan vara ett användbart verktyg för framtida givarutveckling på Scania. Däremot kan riggen inte återskapa de processer som är intressanta med den hårdvara som var tillgänglig vid tillfället. Förbättringar av riggens hårdvara måste göras för att kunna simulera de drivlinekomponenterna som är av intresse för utveckling av varvtalsgivare.
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Richmond, Colin. "Development of high efficiency high speed permanent magnet generator." Master's thesis, Faculty of Engineering and the Built Environment, 2019. http://hdl.handle.net/11427/30972.
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Renewable energy technology is steadily gaining importance in the energy market because of the limited nature of fossil fuels, as well as the political pressures to reduce carbon emissions. To ensure sustainable development, adequate and affordable energy should be made available to satisfy the demand of electric energy. The High Speed Permanent Magnet (HSPM) generator is designed and developed and is expected to deliver 10 kW output power as well as to achieve a speed of 30000 RPM, however, to achieve a compact and efficient design with lower excitation losses, magnetizing currents and rotor losses requires the HSPM generator to be operated at high rated speeds of approximately 30000 RPM. However, at high speeds these machines produce a substantial amount of heat. This makes the thermal management of these machines difficult and complicated, which leads to demagnetization and the reduction of the output power and shortens the lifetime of the critical components such as the bearings. This thesis presents the design and development of the HSPM generator. It also identifies the heat generated by means of electromagnetic, mechanical and core losses. The development of an adequate cooling system (cooling jacket) is presented to avoid hot spots in the generator and thermal damage to the magnets, resulting in demagnetization. The use of pressurized oil air particles as a lubrication method for the bearings of the generator is also considered to avoid: thermal damage and starvation at the rolling element and to address the predominant concern of effectively cooling the HSPM generator ball bearings at elevated speeds. The HSPM generator is designed and developed to operate at a maximum speed of 30000 RPM to deliver 10 kW output power and is subjected to 80~92°C temperature rise with an idle power consumption of ~2kW, enough to cause hot spots on the generator, demagnetization of the magnets and severe impact to the rolling elements of the bearings. The developed cooling jacket and the newly developed oil air mist lubrication arrangement enables the control of the temperature rise of the generator and the temperature rise at the rolling element, respectively. A steady state analysis was also carried out at motor maximum power output to determine its safe operation with the objective of finding an optimal operating condition by performing a parametric study on the effect of cooling. A 3D steady state model of a 10-kW electric permanent magnet machine was generated and investigated with one cooling jacket layout. The end windings and bearings were not considered to simplify the motor model. Numerical analysis is performed with two different coolant flow rates, no flow and maximum flow (3.5 m3 /h) with special emphasis on the maximum motor temperature. The analytical calculations for the role of coolant flowrate on heat transfer characteristics for a high speed generator, showed that the convection heat transfer coefficient increases with an increase in flowrate (0.3 – 3.5 m3 /hr), while the numerical simulations showed that the maximum coolant flowrate conditions achieved lower temperature generation (27.9°C at the front bearing) throughout the generator compared to no coolant flowrate (43.7°C at the front bearing). The detailed understanding of the effects of these parameters on the generator’s temperature field will help in validating the performance of the generator with actual results.
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Ho, Chi-kin. "Speed of plan making for sustainable development : determinants and implications /." View the Table of Contents & Abstract, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38289428.
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Nchaba, Teboho. "Verification of gridded seasonal wind speed forecasts over South Africa." Master's thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/4970.
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Includes abstract.Includes bibliographical references.
The Climate System Analysis Group (CSAG) at the University of Cape Town produces provisional global and Southern African seasonal wind forecasts generated using the United Kingdom Meteorological Office Atmospheric General Circulation Model (AGCM) HadAM3P (non-standard version of HadAM3). This study examines the quality of the seasonal wind speed forecasts through a forecast verification process for continuous variables using reanalysis products of the National Centers for Environmental Prediction and the Department of Energy (NCEP-DOE) as observations data. The verification analyses are performed using summary measures Mean Error (ME), Mean Absolute Error (MAE), Mean Squared Error (MSE), correlation coefficients, Linear Error in Probability Space (LEPS) and exploratory methods, scatter and conditional quantile plots. These methods are used to determine the aspects of forecast quality namely, bias, accuracy, reliability, resolution, and skill over a 20 year period (1991 to 2010). The results of the study have determined that the use of both accuracy and skill measures for the verification analyses provide more information about the quality of the forecasts, as opposed only one of these. In all provinces, the highest quality seasonal wind speed forecasts are made at 500 hPa and the lowest quality forecasts at 1000 hPa. Furthermore regions, pressure levels, and seasons with the highest forecast quality share the common characteristic that their wind speeds are relatively high. The forecasts add value to the climatology and thus are a useful tool for wind assessment at a seasonal scale. It is suggested that adding spatial resolution to the forecasts through downscaling may prepare them for use in applications such as wind power output forecasting.
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王穎琛 and Wing-sum Angela Wong. "Possibility of the development of high speed train between Hong Kong and Mainland China." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B31627699.
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Chase, David Roger. "Development of an efficiency test methodology for high-speed gearboxes." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1209661381.
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Satija, Aman. "Development of a high speed three-dimensional flow visualization technique." Auburn, Ala., 2007. http://repo.lib.auburn.edu/07M%20Theses/SATIJA_AMAN_1.pdf.
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Grobler, Barend. "Development of a high speed planing trimaran with hydrofoil support." Thesis, Link to the online version, 2007. http://hdl.handle.net/10019/632.
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Ho, Chi-kin, and 何志堅. "Speed of plan making for sustainable development: determinants and implications." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B38988926.
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Alava, Juan Manuel. "Formation and development of bread structure in high speed breadmaking." Thesis, University of Reading, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288681.
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Kim, Ee-Eul. "Development of high-speed CCD control system for adaptive optics." Thesis, University College London (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300785.
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Robbins, David James. "Development of computational fluid dynamics methods for low-speed flows." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708407.
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Schow, Clint Lee. "Development of a high-speed, monolithically integrated silicon optical receiver /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.
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Ker, Pin Jern. "Development of high speed low noise InAs electron avalanche photodiodes." Thesis, University of Sheffield, 2012. http://etheses.whiterose.ac.uk/3219/.
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Melibaeva, Sevara (Sevara Mukhtarovna). "Development Impacts of high-speed rail : megalopolis formation and implications for Portugal's Lisbon-Porto High-Speed Rail Link." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/60807.
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Thesis (S.M. in Transportation)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 195-203).
High-speed rail (HSR) has been gaining acceptance worldwide with development of rail technology and rising concerns over climate change and congestion in airports and on roads. The implementation of high-speed rail lines also plays an important role in reshaping the travel patterns and activities of people and consequently change the ways cities develop. An interesting indirect implication of HSR is the potential for megalopolis formation created by fusion of multiple cities linked by HSR. An overall consensus is present in the existing theoretical literature as to what development impacts may be from the HSR investment, including the importance of the resulting agglomeration externalities and formation of megalopolises. However, the complexity of the issue leaves the questions about the causal effect of HSR on economic growth open. This thesis studies the existing empirical evidence and experiences of HSR corridors in Japan, France and Germany to explore qualitatively the phenomenon of "megalopolis" formation as a result of a HSR link, and the evidence of economic development effects on urban areas along these corridors. Portugal among other countries is also planning the deployment of a HSR network in the near future as an effort to stimulate the country's economy and to integrate with the rest of the European Union. The findings and lessons from the case studies are applied to Portugal's proposed Lisbon-Porto HSR corridor. Several possibilities of future scenarios of megalopolis forms and the associated impacts are discussed and analyzed. As a result of improved accessibility and increased interaction between the cities stimulated by HSR, emergence of a megalopolis is possible in different forms along the planned Lisbon-Porto HSR corridor. The critical factor for the formation of a megalopolis is the increased interaction between the cities driven by newly generated traffic and increase in the number of one-day trips. These new travel patterns within a megalopolis may lead to either creation of new economic growth or redistribution of economic activity. The spatial distribution of growth is non-uniform, which may essentially lead to potential winners and losers from HSR. This research is intended to be of value to policy-makers in the railway industry.
by Sevara Melibaeva.
S.M.in Transportation
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Jackson, Keith. "The development of a database of rock properties to assist in the design and development of crushing plant." Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301696.
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Fowkes, Andrew J. "Methods to inform the development of heavy goods vehicle speed limit policy." Thesis, Cranfield University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309691.
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Jogineedi, Rohit. "Development of Comparative Wear Test of ASTM G75 Standard." OpenSIUC, 2017. https://opensiuc.lib.siu.edu/theses/2240.
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AN ABSTRACT OF THE THESIS OF ROHIT JOGINEEDI, for the Master of Science degree in Mechanical Engineering and Processes, presented on 11/06/2017, at Southern Illinois University Carbondale. TITLE: DEVELOPMENT OF COMPARATIVE WEAR TEST FOR ASTM G75 STANDARD MAJOR PROFESSOR: Dr. Peter Filip Industries related to tribology field invest huge amounts in testing products they handle. Most of their budget goes into running tests on corresponding friction, wear or lubrication testing instruments. These tests are observed to be consuming more time with an increase in operational costs. This gained importance among industries for developing economical testing methods designed to run on one or more machines to study tribological conditions. As friction and wear are system properties, change in system variables like distance, velocity, time and area can have notable impact on those properties. This paper discusses about various approaches to develop comparative test on sub scale testers for ASTM G75 standard. Scaling Laws of Physics and comparison of wear mode are two approaches used in this paper to justify the comparative test developed for ASTM G75 on a bench top tester developed by Bruker. Results from the ASTM G75 standard and the UMT are compared and concluded that scaling strategies cannot be used to replicate the standard test methods on sub scale testers but comparison of wear mode could help. This proposed comparative test for ASTM G75 is observed to have lower operational costs thereby decreasing the amount of investment on testing friction or wear products in an industry.
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Douglas, David N. "Development of a high speed, high efficiency LA-ICP-MS interface." Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/12164.
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Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) is now a well established analytical technique used to sample solid materials and determine their elemental composition. Two areas that are becoming increasingly important, and for which LA-ICP-MS is a key tool, are bio-imaging and the analysis of micro-particulates. However, current instrumental designs limit the practicality of the technique for these applications. This study investigates the development of a high speed, high efficiency LA-ICP-MS interface through modelling of the flow dynamics of a newly designed laser ablation cell and experimental investigation of single laser pulse response. Through this work the Sniffer-Dual Concentric Injector interface was realised. This interface reduced particle residence times within the laser cell and transport tubing. The interface was also used to investigate turbulence related aerosol dispersion within the ICP and potential designs to overcome this. The resulting design yields an interface with improved sensitivity and reduced aerosol dispersion such that a lower limit of detection is achieved, important when considering the mass of analyte in a single cell or micro-particulate, compared to existing designs. Thus the interface can be used to improve image spatial resolution as the ablation spot size, and thus pixel information, can be reduced; and also reduces total analysis time. The calibration technique Laser Ablation of a Sample In Liquid (LASIL) was also investigated as a means of calibration for solid samples. The investigation lead to the development of LASIL in a droplet, a technique that can be used to calibrate solid samples when a matrix matched standard is unavailable. The mechanism of the technique resulted in an improved laser-energy sample coupling efficiency and a reduction in the liquid to ablated mass ratio, thus decreasing sampling time. As the technique captures the ablated particulate in solution, post chemistry techniques can be used to remove analyte interferences.
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Kancharla, Akshitha, and Akhil Pannala. "Factors for Accelerating the Development Speed in Systems of Artificial Intelligence." Thesis, Blekinge Tekniska Högskola, Institutionen för programvaruteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-18420.
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Background: With the increase in the application of Artificial Intelligence, there is an urge to find ways to increase the development speed of these systems (time-to-market). Because time is one of the most expensive and valuable resources in software development. Faster development speed is essential for companies to survive. There are articles in the literature that states the factors/antecedents for improving the development speed in Traditional Software Engineering. However, we cannot draw direct conclusions from these factors because development in Traditional Software Engineering and Artificial Intelligence differ. Objectives: The primary objectives of this research are: a) Conduct a literature review to identify the list of factors that affect the speed of Traditional Software Engineering. b) Perform an In-depth interview study to evaluate whether the listed factors of Traditional Software Engineering can be applied in accelerating the development of AI systems engineering. Methods: The method chosen to address the research question 1 is the Systematic Literature Review. The reason for selecting Systematic Literature Review (SLR) is that we follow specific well-defined structure to identify, analyze and interpret the data about the research question with the evidence. The search strategy Snowballing is the best alternative for conducting SLR as per the guidelines are given by Wohlin. The method chosen to address the research question 2 is an In-depth interview study. We conduct interviews to gather information related to our research. Here, the participant is the interviewee, who may be a data scientist or project manager in the field of AI and the interviewer is a student. Each interviewee lists the factors that affect the development speed of AI systems and rank them based on their importance using Trello. Results: The results from the systematic literature is the list of papers that are obtained from the snowball sampling. From the collected data, factors are extracted which are then used for the interviews. The interviews are conducted based on the questionnaire that was prepared. All the interviews are recorded and then transcribed. The transcribed data is analyzed using Conventional Content Analysis. Conclusions: The study identifies the factors that will help accelerate the development speed of Artificial Intelligence systems. The identified factors are mostly non-technical such as team leadership, trust, etc. By selecting suitable research methods for each research question, the objectives are addressed.
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Vandyke, Alex J. "Development of a High-Speed Rail Model to Study Current and Future High-Speed Rail Corridors in the United States." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/76794.
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A model that can be used to analyze both current and future high-speed rail corridors is presented in this work. This model has been integrated into the Transportation Systems Analysis Model (TSAM). The TSAM is a model used to predict travel demand between any two locations in the United States, at the county level. The purpose of this work is to develop tools that will create the necessary input data for TSAM, and to update the model to incorporate passenger rail as a viable mode of transportation. This work develops a train dynamics model that can be used to calculate the travel time and energy consumption of multiple high-speed train types while traveling between stations. The work also explores multiple options to determine the best method of improving the calibration and implementation of the model in TSAM. For the mode choice model, a standard C logit model is used to calibrate the mode choice model. The utility equation for the logit model uses the decision variables of travel time and travel cost for each mode. A modified utility equation is explored; the travel time is broken into an in-vehicle and out-of-vehicle time in an attempt to improve the model, however the test determines that there is no benefit to the modification. In addition to the C-logit model, a Box-Cox transformation is applied to both variables in the utility equation. This transformation removes some of the linear assumptions of the logit model and thus improves the performance of the model. The calibration results are implemented in TSAM, where both existing and projected high-speed train corridors are modeled. The projected corridors use the planned alignment for modeling. The TSAM model is executed for the cases of existing train network and projected corridors. The model results show the sensitivity of travel demand by modeling the future corridors with varying travel speeds and travel costs. The TSAM model shows the mode shift that occurs because of the introduction of high-speed rail.Master of Science
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Lam, Kwun-yi. "The prospects of Maglev for Hong Kong's railway development." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk:8888/cgi-bin/hkuto%5Ftoc%5Fpdf?B23339159.
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Benavides, Amanda Michelle. "Early neurodevelopmental outcomes in preterm infants: memory, attention, & encoding speed." Diss., University of Iowa, 2017. https://ir.uiowa.edu/etd/5415.
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Due to a steady increase in the number of babies born prematurely over the past 20 years, prematurity (a birth occurring before 37 weeks gestation) has emerged as an important public health concern. Even with improved survival of these infants, they remain at risk for many unfavorable health outcomes. Most of those risks include cognitive and behavioral deficits that show up later in life, highlighting the importance of studying the development of the brain, in particular. The current study investigates brain development outcomes in the first years of life using: (1) structural magnetic resonance imaging (MRI) to study brain structure, and (2) three novel cognitive assessments of visual working memory, attention, and speed of processing information. Healthy 12-month-old infants were recruited through University of Iowa’s Neonatal Admissions Registry. An MRI imaging acquisition protocol was developed in order to scan infants during their naptime without sedation. Additionally, a new automatic approach to classifying areas of the brain was developed at the University of Iowa Department of Radiology for 12-month-old brain images. These novel cognitive assessments are based on infant eye movements (including how long it takes for an infant to react to certain stimuli and the direction of their looking). Results from this study support the use of these cognitive tasks to detect specific functional changes in performance based on gestational age. Therefore, these tasks may be potential early markers of risk in preterm populations, but continued investigations are necessary to fully elucidate early brain outcomes during this critical period of development.
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Roach, Neil. "The Biomechanics and Evolution of High-Speed Throwing." Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10609.
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Throwing with power and accuracy is a uniquely human behavior and a potentially important mode of early hunting. Chimpanzees, our closest living relatives, do occasionally throw, although with much less velocity. At some point in our evolutionary history, hominins developed the ability to produce high performance throws. The anatomical changes that enable increased throwing ability are poorly understood and the antiquity of this behavior is unknown. In this thesis, I examine how anatomical shifts in the upper body known to occur during human evolution affect throwing performance. I propose a new biomechanical model for how humans amplify power during high-speed throwing using elastic energy stored and released in the throwing shoulder. I also propose and experimentally test a series of functional hypotheses regarding how four key shifts in upper body anatomy affect throwing performance: increased torso rotational mobility, laterally oriented shoulders, lower humeral torsion, and increased wrist hyperextensability. These hypotheses are tested by collecting 3D body motion data during throws performed by human subjects in whom I varied anatomical parameters using restrictive braces to examine their effects on throwing kinematics. These data are broken down using inverse dynamics analysis into the individual motions, velocities, and forces acting around each joint axis. I compare performance at each joint across experimental conditions to test hypotheses regarding the relationship between skeletal features and throwing performance. I also developed and tested a method for predicting humeral torsion using range of motion data, allowing me to calculate torsion in my subjects and determine its effect on throwing performance. My results strongly support an important role for elastic energy storage in powering humans’ uniquely rapid throwing motion. I also found strong performance effects related to anatomical shifts in the torso, shoulder, and arm. When used to interpret the hominin fossil record, my data suggest high-speed throwing ability arose in a mosaic-like fashion, with all relevant features first present in Homo erectus. What drove the evolution of these anatomical shifts is unknown, but as a result the ability to produce high-speed throws was available for early hunting and likely provided an adaptive advantage in this context.Anthropology
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Mester, Christian. "Development of high speed integrated circuit for very high resolution timing measurements." Bonn Physikalisches Inst, 2009. http://d-nb.info/1001231333/34.
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Caulfield, F. Donald. "Electromechanical Actuator Development for Integrated Chatter Prediction on High Speed Machining Centers." NCSU, 2002. http://www.lib.ncsu.edu/theses/available/etd-04222002-234733/.
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Machine tool chatter imposes limitations on the productivity and quality of modern high speed machining (HSM) operations. It has been shown that chatter prediction and avoidance strategies can lead to increased machining productivity if certain modal characteristics of the machine are known. The objectives of this research are to design and demonstrate an electromechanical actuator (EMA) to easily and accurately identify these characteristics. Design specifications for this actuator reflect a wide range of machine tools and operating conditions. A simulation-based design strategy is employed, based on traditional electromechanical analysis, finite element analysis (FEA), and computer simulations to ensure performance meets the design specifications. A prototype EMA system is built to validate the analytical results and demonstrate its capabilities as part of an automated chatter prediction and avoidance system. The EMA is shown to generate the required modal characteristics, namely frequency response functions (FRFs) and stability lobe diagrams (SLDs) quickly, accurately, and with fewer technical skill requirements than other vibration testing methods. Experimental machining tests demonstrate that the EMA can be an effective component of an integrated chatter prediction and avoidance system.
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Frew, David Anthony. "The design, development and vibration analysis of a high-speed aerostatic bearing." Thesis, Link to the online version, 2007. http://hdl.handle.net/10019/362.
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Hoefer, Ulrike Martina. "Design and development of a high-speed motor for a vacuum pump." Thesis, University of Newcastle Upon Tyne, 2008. http://hdl.handle.net/10443/758.
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Turbomolecular pumps require a motor to drive them at speeds of up to 90,000 rpm. These high-speed motors are typically brushless permanent magnet motors that are specifically designed for the application. Intellectual property rights over the design lock the company into one single supplier. Also low manufacturing volumes make the motor expensive to produce. To stay competitive continuous cost reductions or product improvements are necessary. This can only be achieved by looking at new materials, alternative manufacturing methods and simplified assembly processes. The aim of this project is to replace an existing laminated, high-speed (60,000rpm) motor with a new low-cost design. Special considerations need to be given to the motor design with regards to minimising losses due to the high operating speed and the fact that the motor operates in a vacuum. A machine design employing a simple, 3-tooth segmented stator made from soft magnetic composites (SMC) and using non-overlapping coils, and a `deep' plastic bonded magnet on the rotor is proposed to deliver low rotor losses and low manufacturing costs. Four SMC prototype motors have been built, which have led to the following discoveries: (1) Bulk eddy currents in the SMC material cannot be neglected and need to be taken into account separately as a function of the actual component size and shape. (2) A process is suggested to improve the iron loss calculation in SMC, which is evaluated against the prototypes built. (3) SMC material properties are adversely affected by prototype machining, leading to higher iron losses than initially expected. (4) The segmented SMC design has proven to be commercially very attractive. During testing a large sensitivity of the magnetically supported pump shaft to the inherent unbalanced magnetic pull (UMP) force of the 3-tooth, 2-pole design was discovered. This led to a practical and theoretical study into the effects of UMP in this application. An alternative design that avoided the inherent UMP was required, and a 6- tooth, 4-pole motor has been designed and built. For reasons of minimising risks laminations were chosen as the stator material rather than SMC. Test results of this motor in the pump have been successful and the motor has been selected to go into the next generation of turbomolecular pumps.
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Spisso, Ivan. "Development of a prefactored high-order compact scheme for low-speed aeroacoustics." Thesis, University of Leicester, 2013. http://hdl.handle.net/2381/28635.
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A new class of cost-optimized prefactored high-order compact schemes is developed for shockfree error-bounded aeroacoustic applications. The cost-optimization theory of Pirozzoli (2007), based on the minimization of the computational cost for a given level of error, is applied to a class of prefactored compact sixth-order schemes. They are extended to obtain a new class of time-explicit cost-optimized schemes. Appropriate high-order prefactored boundary closures are coupled with the new interior schemes. Their effect on the stability and accuracy of the interior schemes and their wave propagation characteristics in Fourier space are investigated. More conventional non-reflecting boundary conditions are shown to display an impedance mis-match, reducing the order of accuracy of the overall scheme. An 11-point stencil with double precision accuracy is used as the prefactored interior boundary stencil. It shows a better performance in spectral sense compared to the equivalent ones available in literature. An eigenvalue analysis is performed, to verify the stability of the prefactored cost-optimized schemes coupled with the boundary closures. Characteristics based boundary conditions and absorbing layers are evaluated. A parallelization strategy, based on a finite-sized overlapping interface, is presented and weak scalability tests results are shown. The theoretical roll-off error of the new schemes agree well with the computed norm error roll-off between the analytical prediction and the numerical experiments, for a monochromatic sinusoidal test-case. There is a good agreement between the predicted percentage cost-saving of the one-dimensional cost function and the savings in computational time from the numerical tests. A 22% computational cost-saving at the design level of error is achieved. Sample applications to broadband and two-dimensional space benchmark problems demonstrate the low error-bounded and high-order accuracy characteristics of the baseline scheme for aeroacoustic applications.
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Picco, Loren Michael. "Development and applications of a high-speed atomic force microscope for nanoscience." Thesis, University of Bristol, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.441668.
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Kim, Ki Hean. "Development of high-speed two-photon microscopy for biological and medical applications." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/32383.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.Includes bibliographical references (p. 135-144).
Two-photon microscopy (TPM) is one of the most powerful microscopic technologies for in-vivo 3D tissue imaging up to a few hundred micrometers. It has been finding important applications in neuronal imaging, tumor physiology study, and optical biopsy. A practical limitation of TPM is its slow imaging speed (0.3 1 frames/s). We designed high-speed two-photon microscopes (HSTPMs) whose imaging speed is more than 10 times faster than traditional TPM, while their imaging depths, image contrast are comparable to those of TPM. The first high speed system is HSTPM based on polygonal mirror scanner. The scanning speed reaches 13 frames/s for typical tissues using a polygonal mirror scanner. This system is based on single-focus scanning and single-pixel signal collection. The usage of higher input power is required to compensate for the signal reduction due to higher scanning speed. However, since fluorescence signal is ultimately limited by the saturation of fluorophores due to their finite lifetimes, is the signal to noise ratio (SNR) of single focus scanning systems are also ultimately limited at high speed. This problem is circumvented in a second system based on parallelization by scanning specimens with multiple foci of excitation light and collecting signals with spatially resolved detectors. The imaging speed is increased proportional to the number of foci and similar excitation laser power per focus circumventing the problem of fluorophore saturation. However, it has been recognized that this method is severely limited for deep tissue imaging due to photon scattering.
(cont.) We quantitatively measured the photon scattering effect and demonstrated that its image resolution is the same as conventional TPM but its image contrast is degraded to the faster signal decay with the increase of imaging depth. We designed a new MMM based on multi-anode photomultiplier tube (MAPMT) which utilizes the advantage of MMM in terms of parallelization but overcomes the emission photon scattering problem by optimizing the design detector geometry. This method achieved equivalent SNR as conventional TPM with imaging speed more than 10 times higher than TPM. We applied these HSTPMs to a number of novel biomedical applications focusing on studying biological problems that needs to resolve the high speed kinetics processes or or the imaging of large tissue sections with subcellular resolution to achieve the requisite statistical accuracy. In the study of transdermal drug delivery mechanisms with chemical enhancers,, large section imaging enables microscopic transport properties to be measured even in skin which is highly topographical heterogeneous. This methodology allowed us to identify the novel transport pathways through the stratum corneum of skin. In the study of tumor physiology, microvasculature in tumor tissue deep below the surface was characterized to be densely distributed and tortuous compared to that of normal tissue. The interaction of leukocyte and endothelium in tumor tissue was measured by imaging the kinetics of leukocyte interaction with blood vessel wall in tumor tissues using HSTPM. The capability of large section imaging was further applied to develop a 3D tissue cytometer with the advantages that cell-cell and cell- extracellular matrix interaction can be quantified in tissues.
(cont.) The statistical accuracy of this instrument was verified by quantitatively measuring cell population ratios in engineered tissue constructs composed of a mixture of two cell subpopulations. Further, this 3D tissue cytometer was applied to screen and to identify rare recombination events in transgenic mice that carry novel fluorescent genetic reporters.
by Ki Hean Kim.
Ph.D.
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Kahnert, Pascal. "Development and Optimisation ofInnovative Running Gear Conceptsfor an Ultra-High-Speed Train." Thesis, KTH, Spårfordon, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-180438.
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Since the last ten to 15 years, railway operators have to face new challenges which are an increased demand on comfort and high safety requirements, increased energy costs and the high competitive market situation. German Aerospace Center, DLR is designing a novel concept of an ultra-high-speed train with distributed propulsion system—the Next Generation Train (NGT). It consists of two Power units and eight powered intermediate cars. The intermediate cars are characterised by powered single-wheel single running gears supporting the low-floor concept within the whole train, re-sulting in both effective usage of the inner space but less space for the run-ning gears itself. Additionally, the traditional guiding system with wheel-sets cannot be applied. The first goal of this Master’s thesis is the analysis of the state of the art for unconventional running and driving gears to get an overview of possi-ble and operating technologies. Based on this research and previous spec-ifications for the train, a technical specification for the running gear was created. This led to the development of a number of different concepts un-der consideration of the available space and an optimised arrangement of relevant components. After a conclusion and evaluation of these concepts, a CAD implementation of the relevant structural elements of the selected variant is the final goal of this thesis. Additionally to the technical specifi-cations, the focus lies on lightweight design to support the stringent weight concept of the NGT. However, the accessibility for assembling and mainte-nance is considered, too. The result is a CAD model of only one of doubtless more than a dozen possible variants. Hence, possible changes at specific parts are addressed; advantages and disadvantages were discussed. Finally, the concept was evaluated on the basis of the underlying technical specification.Järnvägsoperatörer har under de senaste 15 åren stött på nya utmaningar genom ökade krav på komfort och säkerhet, högre energikostnader och en starkt konkurrensutsatt marknat. German Aerospace Center, DLR, arbetar med att ta fram ett nytt koncept för ett ultra-höghastighetståg – The Next Generation Train (NGT). Det består av två lok och åtta mellanliggande motorvagnar. Samtliga motorvagnar har ett genomlöpande lågt golv, ett koncept som möjliggörs genom att använda drivna oberoende roterande hjul, vilket resulterar i ett effektivt utnyttjande av vagnsutrymmet tack vare att framdrivningsutrustningen kräver mindre plats. Detta vore inte möjligt med traditionella hjulpar. Det första målet med det här examensarbetet är att genom analys av den nya tekniken för löp- och drivutrustning få en överblick över tänkbara och redan tillämpade tekniker. Baserat på denna studie och tidigare specifikationer för tåget kunde en teknisk kravspecifikation för löp-utrustningen tas fram. Flera olika koncept utvecklades med hänsyn till det tillgängliga utrymmet och med en optimerad disponering av relevanta komponenter. De olika koncepten sammanställdes och utvärderades, varefter ett av dessa valdes för vidare implementering i CAD, vilket var examensarbetets slutgiltiga mål. Utöver den tekniska kravspecifikationen så ligger fokus på att skapa en lättviktsdesign som uppfyller NGT-tågets hårda viktkrav, men även tillgängligheten för montering och service har beaktats. Resultatet är en CAD-modell av en av de tveklöst mer än tjugotal andra möjliga varianterna. Därför har potentiella förändringar av specifika delar belysts och dess fördelar och neckdelar har diskuterats. Slutligen så har det valda konceptet utvärderats utifrån den underliggande tekniska kravspecifikationen
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Kirkby, P. A. "The development of a high speed 3D 2-photon microscope for neuroscience." Thesis, University College London (University of London), 2010. http://discovery.ucl.ac.uk/20463/.
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The progress of neuroscience is limited by the instrumentation available to it for studying the brain. At present, there is a serious instrumentation gap between functional Magnetic Resonance Imaging (fMRI) of whole brains and the microscopic scale functional imaging possible with today’s optical microscopes and electrophysiology techniques, such as patch clamping of individual neurons. This thesis describes the development of a new extension to optical microscopy that enables refocusing within 25 microseconds rather than the large fraction of a second possible by moving the sample or objective. The system is capable of refocusing a laser beam that is monitoring activity in 3D samples of live brain tissue 300 times faster than previously possible. This will make practical a new type of optical functional imaging for studying small sub-networks of neurons containing up to about 30,000 neurons at up to 30,000 sub micrometre sized monitored points of interest per second. The thesis describes the development of a detailed design for a new type of 3D scanner that uses Acousto-Optic Deflectors (AODs) to diffractively deflect and focus an intense laser beam beneath a conventional microscope objective. The fluorescence of calcium sensitive dyes in live neurons is used to monitor action potentials conveying signals between neurons. The optical and systems engineering problems and design trade-offs involved are discussed in detail. The results of extensive computer modelling are described and innovative solutions to several key optical physics based engineering problems are explained. The practical problems found in building a prototype machine incorporating these innovations are described and the encouraging first operational results from the machine reported.
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Lin, Ken-Pien, and 林肯編. "Development of a Low-Speed Wheel Generator." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/35723397266589711166.
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碩士逢甲大學
電機工程所
93
The purpose of this thesis is to design a low-speed small power permanent magnet generator for use in a bicycle to light the lamps. Due to the low energy consumption and low operation voltage, the LED lamps are used and the cheaper magnet, such as ferrite is chosen in the design. In this thesis finite element analysis method is used to analyze the magnetic circuit of the prototype generator, and adjust each parameter that we get from Flux-2D to meet the demands for LED lamps to light. In addition, Is-Spice software is used to design a regulator circuit for protecting LED lamps. The test results of the regulator circuit have been found satisfactory for the purpose of protection.
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Wang, Hsing-Wen, and 王幸雯. "The Development of Children''s Speed Concept." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/80924161710202575148.
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Lee, Chen-Huang, and 李政潢. "The Development of High Speed Human-Power Boat." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/98263566302861072388.
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碩士大同大學
機械工程學系(所)
94
The subject of this essay is to design a human-power boat with sailing speed reaching 5m/s. This design emphasizes upon using chain as propel system. Turning chain to 90°, stamping power is directly delivered to propeller. Through firmly jointed chain and gear, whose property are not being affected easily by environment, we hope to bridge over the effect of water resistance.
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Minnaar, Ulrich John. "Development of a programmable load." Thesis, 2006. http://hdl.handle.net/10539/1696.
Full textAbstract:
Student Number : 0400486V -
MSc (Eng) dissertation -
School of Electrical and Information Engineering -
Faculty of Engineering and the Built EnvironmentThe Voltage Dip Test Facility at the University of the Witwatersrand utilises a resistive load during testing of variable speed drives. This method produces valuable results regarding the performance of drives under dip conditions. It has been shown that load type does influence the performance of drives and this variation cannot be tested under current conditions as only linear loading is attainable with resistive loads. This thesis proposes a programmable load based on the concept of field-oriented control of an induction motor. The concepts involved with field-oriented control are discussed and shown to be suitable for this application. An implementation strategy utilising custom-designed software and an off-the-shelf VSD is developed and executed. The performance of the programmable load is analysed under both steady-state and dynamic conditions.
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Chiou, Tai-Jung, and 邱泰榕. "A Study on High Speed Railroad Development in Japan." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/91351845771482536961.
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Lu, Jun-Shen, and 陸濬紳. "Development of Offline Measurement System for High Speed Boats." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/z799hk.
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碩士國立高雄海洋科技大學
造船及海洋工程研究所
102
The research is about to develop an offline-measurement system for the high speed boats. In the system, Accelerometers will be used to measure the acceleration of the structural response, strain gage will be used to measure the strain of boat structure. Also, GPS and attitude indicator in the system are used to calculate parameter of position, speed and motion status that collect and report the update of boat state. This system is utilized by LabVIEW graphical language and embedded type of National Instrument (NI) control chassis with C series I/O modules combination. The measured events of this project completed for the parameters must be analyzed and experimented in laboratory to ensure their precision. After whole experiment finished in laboratory, we installed the entire system into the high speed boat for a practical performance. Therefore, we are able to understand and detect if it is certainly useful in ocean navigation.
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Hsieh, Nan-Kai, and 謝男凱. "Development of Fault Diagnosis System For High Speed Spindle." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/58813576588746968532.
Full textAbstract:
博士國立臺灣大學
機械工程學研究所
103
During the long machining cycles, the vibration and accompanied noise produced by the machine tool may cause unduly mechanical wear and, consequently malfunction. The inadequate facility limits an effective malfunction pre-warning diagnosis and this often leads to the sudden failure of the spindle. Therefore, it is necessary to rely on the real-time monitor system to enhance the reliability of the machine tool. This research collects the information in the process of production and maintenance, from which the common faults are summarized, and then a constant-preload spindle is used to collect vibration signals and simulate each failure mode. This research also proposes the multi-scale entropy (MSE), in addition to the most common detection of vibration signals, the Fourier analysis. It is used to observe the amplitude of each frequency at each instant. The MSE can be used to calculate the MSE curve which can then be used to correctly identify some defect modes. In order to prevent the failure without warning, this research is designed to extract the threshold of each fault condition by repetitive experiments to develop the defect diagnosis system (DDS). The main objective of the DDS is applied to detect the faults before the run-in period of spindle so that any potential errors can be identified and recognized. These potential damaging factors are detected from the spindle to avoid breaking the bearing during the run-in period. At present, the DDS is applied successfully in the production line for quality control. and the recognition rate of DDS is high up to 90 percent .
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Lin, Chun-Ping, and 林君萍. "The Development of High-Speed Red Light Emitting Diodes." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/64018735352746787793.
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碩士國立清華大學
電子工程研究所
100
In recent years, the light emitting diode (LED) industry have considerable development not only in epitaxial process but also in aspect of package. It’s luminous efficiency has already exceed 100 lm/W, which is the threshold of the green energy representative. Their small mass and volume, solid state construction, multi-color, easy modulation, and long-life characteristics make the solid state lighting become a general trend, and bring a competitive market in people's livelihood and lighting. In our dissertation, we demonstrate a high-speed AlGaInP-based light-emitting diode at wavelength of around 650nm using the wet etching to forming self-confined current injection structure with different diameter of mesa, and the different dimension of bonding pad. And we discusses the design concept, fabrication and performance characteristics of different LEDs device parameters. Our efforts were directed at finding the best compromise between device characteristics and at devising ways to improve modulation behavior without essentially affecting the other parameters. The smaller device dimension will thus lead to the higher 3dB frequency bandwidth. It is attributed to the shorter carrier lifetime at higher current density and smaller RC time constant limited bandwidth.