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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.
11

Developing a formula for the comparison of athletics performances across gender, age and event boundaries based on South African standards

Bekker, S. W. J. 01 1900 (has links)
M. Tech (Department of Information and Communication Technology, Faculty of Applied and Computer Sciences) Vaal University of Technology. / The author addressed the need of parents, school teachers and athletic coaches to be able to assess the level of performance and to compare performances of individual athletes of either gender and in any age group. This was achieved by creating formulas for the following areas in track and field athletics: • Correctly set base standards for all events from the results of 5 year weighted average performances. • Use the base standards to determine comparative standards for all events in all age groups. • Define a function to compare male and female performances in all events. • For all events, generate tables with a range from 0 to 1000 as a comparative measurement. These formulae were created using data from international and national meetings. Different case studies were used for each of the areas and the results were evaluated using the data. In all four areas, it was possible to define hybrid functions with a confidence factor better than 99%. The final performance tables can be updated during revision periods (every 2 to 4 years) by using the national results for the last 5 years. These revisions will be required as implements, tracks and training methods change with time and this will then in turn influence the performances. This is evident from the continuous improvement of records in all events. These tables will not only assist coaches to improve training techniques but it will also facilitate team managers to improve team selections, and it will open the options of meeting organizers to arrange meetings using different formats. As this is a new and unique formulation for measuring performances at junior level in world athletics it can be used as a basis for future improvements in the field of comparative measurement for athletics. Using these tables at senior level it may assist to settle arguments of performance comparisons that are not addressed by the current tables used by the International Amateur Athletics Federation (IAAF). It will also avoid the use of different tables for the same events in standard track and field athletics compared to those used for combined event competitions. The author of the tables used by the IAAF has recognised this work as a new and unique development. Future development will include the automatic update of all functions and creation of tables for publication from a standard Windows® based application. A companion application, using the results from this research, will be developed. This application will address all the administration functions required to conduct a meeting. It will include the preparation for the meeting, capturing of results during the meeting and result reporting after the meeting.
12

Analýza a srovnání ukazatelů herního výkonu u družstev Ženské basketbalové ligy v období sezón 2009/10 - 2018/19 / Analysis and comparison of gaming performance indicators for Woman's basketball leagues in the periodes 2009/10 - 2018/19.

Lain, Eva January 2022 (has links)
Title: Analysis and comparison of gaming performace indicators for Women's basketball league in the period 2009/10 to 2018/19. Objectives: The main focus of this thesis is to compare, based on data acquired from official statistics the quantitative differences in the selected indicators of game performance for teams placed on second, sixth and tenth places in the highest women's basketball competition in the Czech Republic of 10 years the regular season (from the year 2009/10 to 2018/19). Methods: In our thesis we used secondary analysis - data were acquired from the website of the Czech Basketball Federation. Results: Have to show us differences in the performance in our selected indicators of the same places teams in individual seasons for a period of 10 years, differences in the evenness in each indicator between the teams that placed second, sixth and tenth, the summary of the average values, which we compare in each indicator for 10 years of teams placed second, sixth a tenth. Keywords: Basketball, game performance, secondary analysis, quantitative analysis, comparison.
13

High performance simulations of kernel P systems

Bakir, M.E., Konur, Savas, Gheorghe, Marian, Niculescu, I.M., Ipate, F. January 2014 (has links)
No / The paper presents the use of a membrane computing model for specifying a synthetic biology pulse generator example and discusses some simulation results produced by the tools associated with this model and compare their performances. The results show the potential of the simulation approach over the other analysis tools like model checkers.
14

Full Bridge LLC Converter Secondary Architecture Study for Photovoltaic Application

Yan, Jinghui 13 March 2018 (has links)
The increasing global energy demand calls for attention on renewable energy development. Among the available technology, the photovoltaic (PV) panels is a popular solution. Thus, targeted Power Conditioning Systems (PCSs) are drawing increased attention in research. Microconverter is one of the PCS that can support versatile applications in various power line architectures. This work focuses on the comparison of circuit secondary side architectures for LLC converter for microconverter application. As the research foundation, general characteristic of solar energy and PV panel operation are introduced for the understanding of the needs. Previous works are referenced and compared for advantages and limitation. Base on conventional secondary resonant full bridge LLC converter, the two sub-topologies of different secondary rectification network: active, full bridge secondary and active voltage doubler output end LLC converter are presented in detail. The main operating principle is also described in mathematical formula with the corresponding cycle-by-cycle operation to ensure the functional equality before proceeding to performance comparison. Circuit efficiency analysis is conducted on the main power stage and the key components with frequency consideration. The hardware circuit achieved the designed function while the overall hardware efficiency result agrees with analysis. In the implementation, the transformer is costume built for the system pacification. Another part is the parasitic effect analysis. At a high operating frequency and to achieve very high-frequency operation, parasitic effect need to be fully understood and considered as it may have the dominating effect on the system. / Master of Science
15

Performance comparison between NewSQL and SQL : Sharded TiDB vs MariaDB

Johansson, Mathias, Röör, Jonatan January 2020 (has links)
Databases are used extensively for websites and a large amount of websites are built upon Wordpress. Wordpress uses MySQL compatible databases and for many larger websites itcan be imperative to have the best possible performance. Recently, NewSQL databases have been appearing that combine the features of NoSQL databases with SQL compatibility and ACID compliance that is usually not found in NoSQL databases. Due to their recency, thereis a knowledge gap in the literature regarding NewSQL databases. Therefore, this work compares the performance of the NewSQL database TiDB against the SQL database MariaDB in a performance benchmark. The benchmark includes three testing approaches with an aim of testing multiple performance aspects. These include load testing, complex queries and performance in a realistic environment. Results from this thesis show that TiDB achieves better average response time for complex queries and in load testing where the databases and load is large but gets worse results for simple queries and small datasets. MariaDB performs better when used with a web server andwith tests that involve write-operations.
16

A study of trilateral flash cycles for low-grade waste heat recovery-to-power generation

Ajimotokan, Habeeb A. 10 1900 (has links)
There has been renewed significance for innovative energy conversion technologies, particularly the heat recovery-to-power technologies for sustainable power generation from renewable energies and waste heat. This is due to the increasing concern over high demand for electricity, energy shortage, global warming and thermal pollution. Among the innovative heat recovery-to- power technologies, the proposed trilateral flash cycle (TFC) is a promising option, which presents a great potential for development. Unlike the Rankine cycles, the TFC starts the working fluid expansion from the saturated liquid condition rather than the saturated, superheated or supercritical vapour phase, bypassing the isothermal boiling phase. The challenges associated with the need to establish system design basis and facilitate system configuration design-supporting analysis from proof-of-concept towards a market-ready TFC technology are significant. Thus, there is a great need for research to improve the understanding of its operation, behaviour and performance. The objective of this study is to develop and establish simulation tools of the TFCs for improving the understanding of their operation, physics of performance metrics and to evaluate novel system configurations for low-grade heat recovery-to-power generation. This study examined modelling and process simulation of the TFC engines in order to evaluate their performance metrics, predictions for guiding system design and parameters estimations. A detailed thermodynamic analysis, performance optimization and parametric analysis of the cycles were conducted, and their optimized performance metrics compared. These were aimed at evaluating the effects of the key parameters on system performances and to improve the understanding of the performance behaviour. Four distinct system configurations of the TFC, comprising the simple TFC, TFC with IHE, reheat TFC and TFC with feed fluid-heating (or regenerative TFC) were examined. Steady-state steady-flow models of the TFC power plants, corresponding to their thermodynamic processes were thermodynamically modelled and implemented using engineering equation solver (ESS). These models were used to determine the optimum synthesis/ design parameters of the cycles and to evaluate their performance metrics, at the subcritical operating conditions and design criteria. Thus, they can be valuable tools in the preliminary prototype system design of the power plants. The results depict that the thermal efficiencies of the simple TFC, TFC with IHE, reheat TFC and regenerative TFC employing n-pentane are 11.85 - 21.97%, 12.32 - 23.91%, 11.86 - 22.07% and 12.01 - 22.9% respectively over the cycle high temperature limit of 393 - 473 K. These suggest that the integration of an IHE, fluid-feed heating and reheating in optimized design of the TFC engine enhanced the heat exchange efficiencies and system performances. The effects of varying the expander inlet pressure at the cycle high temperature and expander isentropic efficiency on performance metrics of the cycles were significant. They have assisted in selecting the optimum-operating limits for the maximum performance metrics. The thermal efficiencies of all the cycles increased as the inlet pressures increased from 2 - 3 MPa and increased as the expander isentropic efficiencies increased from 50 - 100%, while their exergy efficiencies increased. This is due to increased net work outputs that suggest optimal value of pressure ratios between the expander inlets and their outlets. A comprehensive evaluation depicted that the TFC with IHE attained the best performance metrics among the cycles. This is followed by the regenerative TFC whereas the simple TFC and reheat TFC have the lowest at the same subcritical operating conditions. The results presented show that the performance metrics of the cycles depend on the system configuration, and the operating conditions of the cycles, heat source and heat sink. The results also illustrate how system configuration design and sizing might be altered for improved performance and experimental measurements for preliminary prototype development.
17

A study of trilateral flash cycles for low-grade waste heat recovery-to-power generation

Ajimotokan, Habeeb A. January 2014 (has links)
There has been renewed significance for innovative energy conversion technologies, particularly the heat recovery-to-power technologies for sustainable power generation from renewable energies and waste heat. This is due to the increasing concern over high demand for electricity, energy shortage, global warming and thermal pollution. Among the innovative heat recovery-to- power technologies, the proposed trilateral flash cycle (TFC) is a promising option, which presents a great potential for development. Unlike the Rankine cycles, the TFC starts the working fluid expansion from the saturated liquid condition rather than the saturated, superheated or supercritical vapour phase, bypassing the isothermal boiling phase. The challenges associated with the need to establish system design basis and facilitate system configuration design-supporting analysis from proof-of-concept towards a market-ready TFC technology are significant. Thus, there is a great need for research to improve the understanding of its operation, behaviour and performance. The objective of this study is to develop and establish simulation tools of the TFCs for improving the understanding of their operation, physics of performance metrics and to evaluate novel system configurations for low-grade heat recovery-to-power generation. This study examined modelling and process simulation of the TFC engines in order to evaluate their performance metrics, predictions for guiding system design and parameters estimations. A detailed thermodynamic analysis, performance optimization and parametric analysis of the cycles were conducted, and their optimized performance metrics compared. These were aimed at evaluating the effects of the key parameters on system performances and to improve the understanding of the performance behaviour. Four distinct system configurations of the TFC, comprising the simple TFC, TFC with IHE, reheat TFC and TFC with feed fluid-heating (or regenerative TFC) were examined. Steady-state steady-flow models of the TFC power plants, corresponding to their thermodynamic processes were thermodynamically modelled and implemented using engineering equation solver (ESS). These models were used to determine the optimum synthesis/ design parameters of the cycles and to evaluate their performance metrics, at the subcritical operating conditions and design criteria. Thus, they can be valuable tools in the preliminary prototype system design of the power plants. The results depict that the thermal efficiencies of the simple TFC, TFC with IHE, reheat TFC and regenerative TFC employing n-pentane are 11.85 - 21.97%, 12.32 - 23.91%, 11.86 - 22.07% and 12.01 - 22.9% respectively over the cycle high temperature limit of 393 - 473 K. These suggest that the integration of an IHE, fluid-feed heating and reheating in optimized design of the TFC engine enhanced the heat exchange efficiencies and system performances. The effects of varying the expander inlet pressure at the cycle high temperature and expander isentropic efficiency on performance metrics of the cycles were significant. They have assisted in selecting the optimum-operating limits for the maximum performance metrics. The thermal efficiencies of all the cycles increased as the inlet pressures increased from 2 - 3 MPa and increased as the expander isentropic efficiencies increased from 50 - 100%, while their exergy efficiencies increased. This is due to increased net work outputs that suggest optimal value of pressure ratios between the expander inlets and their outlets. A comprehensive evaluation depicted that the TFC with IHE attained the best performance metrics among the cycles. This is followed by the regenerative TFC whereas the simple TFC and reheat TFC have the lowest at the same subcritical operating conditions. The results presented show that the performance metrics of the cycles depend on the system configuration, and the operating conditions of the cycles, heat source and heat sink. The results also illustrate how system configuration design and sizing might be altered for improved performance and experimental measurements for preliminary prototype development.
18

Participace zahraničních hráček na týmovém herním výkonu družstev naší nejvyšší soutěže žen / Participation of foreign players on team game performance in our highest competition for women.

Minarovičová, Kristýna January 2019 (has links)
Title: Participation of foreign players on team game performance in our highest competition for women. Objectives: The goal of this master's thesis is to compare game performance of foreign players with Czech players from season 1998/1999 to season 2017/2018 in the highest Czech basketball competition for women. The partial goal of the thesis is to find out and observe the evolution of number of foreign players participating in above stated twenty-year period. Methods: In our thesis we used a method of collecting secondary information, which means secondary statistical data analysis. Results: By data analysis we found out, that foreign players were more effective than Czech players in all monitored seasons while comparing played time and reached index of success. The number of foreign players in the highest league was gradually growing until reaching its peak in season 2014/2015. Keywords: globalization, migration in sport, basketball, Czech women's basketball league, foreign players, comparison, game performance
19

Comparing Support Vector Machines with Gaussian Kernels to Radial Basis Function Classifiers

Schoelkopf, B., Sung, K., Burges, C., Girosi, F., Niyogi, P., Poggio, T., Vapnik, V. 01 December 1996 (has links)
The Support Vector (SV) machine is a novel type of learning machine, based on statistical learning theory, which contains polynomial classifiers, neural networks, and radial basis function (RBF) networks as special cases. In the RBF case, the SV algorithm automatically determines centers, weights and threshold such as to minimize an upper bound on the expected test error. The present study is devoted to an experimental comparison of these machines with a classical approach, where the centers are determined by $k$--means clustering and the weights are found using error backpropagation. We consider three machines, namely a classical RBF machine, an SV machine with Gaussian kernel, and a hybrid system with the centers determined by the SV method and the weights trained by error backpropagation. Our results show that on the US postal service database of handwritten digits, the SV machine achieves the highest test accuracy, followed by the hybrid approach. The SV approach is thus not only theoretically well--founded, but also superior in a practical application.
20

Comparison Of Axial Flux And Radial Flux Brushless Dc Motor Topologies For Control Moment Gyroscope Wheel Applications

Yilmaz, Kurtulus 01 May 2009 (has links) (PDF)
In this thesis axial flux and radial flux brushless dc motors will be studied as a drive motor for the control of moment gyroscope wheel. Design equations for axial flux and radial flux brushless dc motor topologies will be reviewed. Based on these equations radial and axial flux motors with different number of poles will be designed that meet control moment gyroscope wheel application requirements. The results will be evaluated in terms of efficiency, torque/mass and torque/volume, and suitability for the control moment gyroscope application.

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