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Objektivizace a míra asociace mezi indikátory herního zatížení a pohybovými předpoklady u elitních hráčů ragby / Objectification and level of association between game performance and physical determinants in elite rugby playersStárka, Daniel January 2021 (has links)
Title: Objectification and degree of association between indicators of game load and movement assumptions in elite rugby players Objectives: The aim was to objectify and measure the association between selected indicators of game load and selected movement assumptions in elite rugby players and measure the association between selected results of different fitness tests. Methods: The research group consisted of 31 players of the Czech rugby team of the senior category. Data were acquired using GPSports. The results from fitness testing provided by the Czech Rugby Union were used as indicators of movement assumptions. In total, three matches were measured. During the individual matches, the total distance covered was measured, the distance covered in individual speed zones (1st zone 0.0-1.8 km/h, 2nd zone 1.8-6.1 km/h, 3rd zone 6, 1-13.0 km/h, 4th zone 13.0-18.0 km/h, 5th zone 18.0-24.1 km/h, zone 6th >24.1 km/h), number of inputs to individual acceleration and deceleration zones (1st zone 1.2- 2.4 m/s/s, 2nd zone 2.4-3.6 m/s/s, 3rd zone 3.6-4.8 m/s/s). Results: The results of the work contain data that are unparalleled in Czech conditions. Tight forwards run 70.50 ± 7.09 m/min lose forwards 73.89 ± 4.25 m/min, inside backs 81.70 ± 11.71 m/min and outside backs 82.82 ± 12.71 m/min. In one match,...
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The Relationships Between Hexagonal Barbell One-Repetition Maximum Deadlift and Maximal Isometric Pulls at Three Different PositionsMiller, Brandon Alexander 15 May 2020 (has links)
No description available.
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Construction and Performance Testing of a Mixed Mode Solar Food Dryer for Use in Developing CountriesFoster, Sean Andrew 30 January 2013 (has links) (PDF)
This study details the construction and performance testing of a mixed mode solar dryer using a combination of direct and indirect solar energy to dry food. One major benefit of this dryer design is its construction. It was simple to construct and was made with low cost materials, to make it feasible for use in developing countries. Previous research has identified several design factors that affect performance and efficiency: product loading density, number of trays, position of the absorber, and chimney type. Performance testing showed that chimney air speeds were not affected greatly by modifying the design aspects of the dryer, with only a small increase occurring when using a box-type chimney. Overall the temperatures were mostly dependent on irradiance, but using a collector-type chimney generally resulted in higher temperatures throughout the dryer. The RH change across the dehydrator was most affected by the number of trays, but the chimney type did have an effect on the RH right at the chimney exit. Efficiency testing showed that product loading density on the trays was tested at 40% and 60% capacity; there was no statistical difference observed for efficiency between the two levels. Our results show that the dryer was more efficient when using the maximum number of trays. The lowest position of the absorber (5 cm from the ground) was found to be most efficient. A box-type chimney was significantly more efficient than the collector-type chimney in this full factorial study.
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Optimizing the Use of Reclaimed Asphalt Pavement (RAP) in Hot Mix Asphalt Surface MixesMeroni, Fabrizio Luigi 12 January 2021 (has links)
The most common use of reclaimed asphalt pavement (RAP) is in the lower layers of a pavement structure, where it has been proven as a valid substitute for virgin materials. Instead, the use of RAP in surface mixes is more limited, with a major concern being that the high RAP mixes may not perform as well as traditional mixes. To reduce risks of compromised performance, the use of RAP has commonly been controlled by specifications that limit the allowed amount of recycled material in the mixes. However, significant cost and environmental savings can be achieved if more RAP is included in the surface layer. This dissertation develops an approach that can be followed to incorporate more RAP in the surface mix while maintaining good performance. The approach is based on the results from three studies that looked at how to optimize the design of the mix, in terms of rutting and fatigue resistance, when more RAP is used.
In the first study, a high RAP control mix and an optimized mix designed using different design compaction energy (65 and 50 gyrations respectively) were compared. The optimization process consisted in the definition of an alternative mix composition that supported the higher binder content allowed by the lower design compaction energy. Using Accelerated Pavement Testing and laboratory characterization it was possible to assess the potential of mix optimization with the objective of improving rutting resistance. The testing showed no indication that the optimized mixes would have rutting problems, supporting the implementation of the reduction of the design compaction energy level. The optimized mix exhibited a similar or superior rutting resistance in the full-scale setting, in the laboratory, and in the forensic investigation.
The second part focused on the production of highly recycled surface mixes capable of performing well. To produce the mixes, a balanced mix design (BMD) methodology was used and a comparison with traditional mixes, prepared in accordance with the requirements of the Virginia Department of Transportation (VDOT) volumetric mix design, was performed. Through the BMD procedure, which featured the indirect tensile cracking test for evaluating the cracking resistance and the Asphalt Pavement Analyzer for evaluating rutting resistance, it was possible to optimize the selection of the optimum asphalt content. Also, it was possible to obtain a highly recycled mix (45% RAP) capable of achieving better overall performances than traditional mixes while carrying a large reduction in production cost.
The final part evaluated the laboratory performance of four different highly recycled surface mixes to support their possible implementation in the state of Virginia. The mixes featured either 30% or 45% RAP, different asphalt contents, the use of a WMA additive, and a rejuvenator. To analyze the mixes' performance in great depth, a three-level (base, intermediate, and advanced) testing framework was defined. Each level was characterized by an increasing degree of complexity and included tests to characterize both the cracking resistance and the rutting resistance. The study aimed at investigating the features of the various laboratory tests. Through the review of the theoretical background, the evaluation of the test procedures, and statistical analysis of the results, it was possible to identify the strengths and weaknesses of each test and to provide guidelines to develop appropriate quality assessment criteria and mix design methodology.
In summary, throughout this research, it was possible to observe that the respect of Superpave mix design requirements alone, with particular reference to gradation limits and volumetric properties, was not guarantee of satisfactory performance in terms of both cracking and rutting resistance. To increase the confidence in the RAP properties, increase the current recycling levels, and introduce more appropriate mix design specifications, BMD could be used (even with simple laboratory tests) to check performance-based criteria. / Doctor of Philosophy / Nowadays, transportation agencies are expected to perform a large number of pavement rehabilitation projects, while facing major limitations in budgetary funds. In order to have safe, efficient, and cost-effective roadways, the economic advantage of recycling is boosting an effort to increase the amount of RAP in asphalt mixtures. In addition, over the past decades, the environmental awareness of the transportation agencies and public increased significantly, pushing even more towards the use of new green technologies.
The use of RAP became noticeable in the 1970s and its popularity increased significantly since that time. However, there are still many open questions which prevent larger uses of recycled materials, mainly related to the design methodology and the field performances of recycled mixtures. Therefore, today there is a large untapped potential that would grow even more the magnitude of pavement recycling and of the associated benefits.
New design procedures, based on the support of laboratory tests to characterize the mixtures, and full-scale experiments are the tools that pavement engineers can use in order to enrich the knowledge of highly recycled road materials and grow the confidence of public agencies and contractors towards these new more sustainable solutions.
Throughout this dissertation it was possible to evaluate new innovative ways of incorporating more RAP in the asphalt mixtures through the analysis of current state of the art and the proposition of new procedures.
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<b>Standardized Performance Testing of Ultrasonic Testing Technicians</b>Rose Marie Raffin (18197035) 25 April 2024 (has links)
<p dir="ltr">Ultrasonic testing (UT) is a commonly used inspection method for buildings and bridges, yet variability in inspector performance has brought the validity of the UT process into question. While practical tests and performance testing are required as part of most UT certification processes and some industry standards, the building and bridge industries currently have no standardized testing body to verify the qualification of UT technicians. This research aimed to develop and implement a possible standardized testing protocol based on the American Welding Society (AWS) structural welding codes. Results from performance tests conducted in this research demonstrated high variability and low precision in UT measurements and generally poor performance amongst the 20 technicians that took part in the tests. It is clear from this research that certification from the existing certification programs do not always indicate qualification. Therefore, standardized performance testing would add value and increase the reliability of UT inspections by identifying those technicians that are clearly unqualified.</p>
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Development of a turf stability assessment method for sports surfacesAnderson, Frazer D. January 2018 (has links)
The majority of outdoor sports are played on natural turf pitches. Throughout the playing season, a pitch has continual player interaction, which, during periods of sustained unfavourable conditions, can cause the turf to tear up (shear) under player contact. This is most evident in Rugby Union scrummages, which create deep divots in the turf and rootzone that reduce player safety and are criticised by the media. However, little is known of the turf/rootzone strength to depth, termed 'shear stability' in this thesis, and there is currently no appropriate means to test this property. In order to explore the shear stability of turf, a device was designed and developed. The prototype device, termed the 'Shear Tester', underwent trial, validation and several redesigns until it was deemed suitable to investigate turf shear stability. A range of natural and hybrid constructions and laboratory-controlled samples were investigated, and the key variables found to influence the shear stability were grass rooting, water content and rootzone density.
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Performance of REST applications : Performance of REST applications in four different frameworksSöderlund, Sverker January 2017 (has links)
More and more companies use a REST architecture to implement applications for an easy to use API. One important quality attribute of an application is the performance. To be able to understand how the application will perform it is important to know how the selected framework perform. By testing the performance of different frameworks it will become easier for software developers to choose the right framework to achieve their requirements and goals. At the time when this paper was written the research in this area was limited. This paper answered the question of which framework between Express, .NET Core, Spring and Flask that had the best performance. To be able to know how frameworks performed the author needed to measure them. One way of measuring performance is with response time from the server. The author used a controlled experiment to collect raw data from which the results was drawn. The author found out that Spring had the best overall performance between the different categories. By analysing the results the author also found out that performance differed a lot between the frameworks in some categories.
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MACHINE LEARNING-ASSISTED LOAD TESTINGIsaku, Erblin January 2021 (has links)
The increasing worldwide demand for software systems involved in society has led to the need where not only functionality is fundamental and addressed, but end-user satisfaction in terms of availability, throughput, and response time is essential and should be preserved. Thus, systems must be evaluated at preset load levels to assess the non-functional quality problems from the closest perspective of real application use. In this context, where the problem involves a high and complex search space, a search-based approach for load test generation is required. This thesis proposes and evaluates an evolutionary search-based approach for load test generation using multi-objective optimization methods consisting of selection, crossover, and mutation operators. In this thesis, load testing is addressed as a multi-objective optimization problem by using four different evolutionary algorithms: Non-dominated Storing Genetic Algorithm II (NSGA-II), Pareto Archived Evolution Strategy (PAES), The Strength Pareto Evolutionary Algorithm 2 (SPEA2), Multi-Objective Cellular Genetic Algorithm (MOCell) as well as a Random Search algorithm. Additionally, this study demonstrates the applicability of the proposed approach by running several experiments, aiming to compare the algorithms’ efficiency based on different quality indicators such as hypervolume, spread, and epsilon. Experimental results show that evolutionary search-based methods can be used to generate effective workloads. Since, all algorithms have found the optimal workload, having the hypervolume values to zero, we believe that the objectives of the problem could be combined as a single objective, hence scalarization techniques can be applicable. Based on the other quality indicators (Spread and Epsilon respectively), NSGA-II and MOCell tend to perform better compared to other algorithms. Finally, the study concludes that multi-objective evolutionary algorithms can be used for load testing purpose, obtaining better results in generating optimal workloads than an existing (adapted) model-free reinforcement learning approach.
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Testování protokolů pro video na vyžádání v programu Apache JMeter / Video on Demand Protocols Testing using Apache JMeterSrnec, Tomáš January 2018 (has links)
The master’s thesis deals with testing the application protocol HLS and RTSP in JMeter program. The aim of this thesis is to design and implement a test modules for both protocols, which will perform stress tests. The first part of thesis describes the types of stress tests, JMeter program for performance testing and video on demand services. Next chapter describes selected protokols, especially HLS and RTSP, which are used in this thesis. The practical part contains the design and implementation of test modules including test plans. Finally, the results are processed and commented.
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Open Source implementace IMS / Open Source IMS implementationsJežek, Jiří January 2020 (has links)
The diploma thesis deals with open source implementations of IMS technology. The theoretical part describes the functioning of IMS and its architecture, including the protocols used, the process of registration and connection establishment, as well as potential security threats to IMS systems. Two open source IMS projects were selected, Open IMS Core and Project Clearwater, on which the work is focused. In its next part, the diploma thesis deals with the description of selected open source IMS projects, this part also includes a description of the implemented security of both projects and a detailed procedure of system installation with any necessary configuration. In its practical part, the diploma thesis focused on performance testing of selected projects using the Abacus 5000 hardware tester. First, initialization tests were performed, which verified the possibility of communication between the tester and the tested projects. Subsequently, it was possible to perform performance testing of selected projects. In performance testing, emphasis is placed on system stability, performance in the area of call set-up speed and response time of SIP messages and speed of user registration in the network, at different load levels. The systems have been tested for both call set-up and user registration. Part of the testing is also the implementation of the flood DoS inviteflood attack and the system's response to the increasing intensity of the attack. The last chapter is devoted to the comparison of selected IMS projects, where the test results are clearly presented. This chapter is partly based on publicly available information, such as the technical documentation of individual projects and possibly publicly available mailing lists. Part of the diploma thesis is also a laboratory task in which the student tries to work with Open IMS Core. The laboratory task focuses on the process of creating a user and his registration in the IMS network, establishing a call between individual users and internal routing in IMS networks. The task focuses mainly on signaling processes within the implemented tasks.
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