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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.
91

Experiments with the pentium Performance monitoring counters

Agarwal, Gunjan 06 1900 (has links)
Performance monitoring counters are implemented in most recent microprocessors. In this thesis, we describe various performance measurement experiments for a program and a system that we conducted on a Linux operating system using the Pentium performance counters. We carried out our performance measurements on a Pentium II microprocessor. The Pentium II performance counters can be configured to count events such as cache misses, TLB misses, instructions executed etc. We used a low intrusive overhead technique to access these performance counters. We used these performance counters to measure the cache miss overheads due to context switches in Linux system. Our methodology involves sampling the hardware counters every 50ps. The sampling was set up using signals related to interval timers. We describe an analytical cache performance model under multiprogrammed condition from the literature and validate it using the performance monitoring counters. We next explores the long term performance of a system under different workload conditions. Various performance monitoring events - data cache h, data TLB misses, data cache reads or writes, branches etc. - are monitored over a 24 hour period. This is useful in identifying activities which cause loss of system performance. We used timer interrupts for sampling the performance counters. We develop a profiling methodology to give a perspective of performance of the different functions of a program, not only on the basis of execution-time but also on the data cache misses. Available tools like prof on Unix can be used to pinpoint the regions of performance loss of programs, but they mainly rely on an execution-time profiles. This does not give insight into problems in cache performance for that program. So we develop this methodology to get the performance of each function of the program not only on the basis of its execution time but also on the basis of its cache behavior.
92

Otahuhu B Power Station condenser in-leakage analysis and condensate monitoring system : a thesis presented in partial fulfilment of the requirements for the degree of Master of Engineering in Electronics Engineering at Massey University, Wellington, New Zealand

Zhang, Heng January 2008 (has links)
Considerable ongoing risk of condenser in-leakage exists at Otahuhu B (OTB) Power Station. The condenser cooling water used at OTB station is corrosive brackish water with exceedingly high sodium and chloride concentrations. Significant signs of corrosion inside the condenser have been found recently. In the event of condenser in-leakage, the salt contaminants in the cooling water will directly enter the Heat Recovery Steam Generator (HRSG) with the potential for significant and costly damage resulting in a long plant outage. A dynamic mathematical model was developed in the thesis to analyse the consequences of condenser in-leakage at OTB station. The analysis results show that the tolerance of the condenser to any leakage of cooling water is almost zero. Because the existing condensate monitoring system is not designed to detect contamination in this time frame, a new fast response system is required to detect condenser in-leakage immediately. A new dedicated fast response condensate monitoring system has been engineered and installed at OTB station as a part of the project scope. The new system dramatically reduces the response time to condenser in-leakage events. Critical instruments utilise multiple redundancy schemes to enhance the availability and reliability of the system. In addition, action level voting, timing, and alarming has been automated to assist operators in making correct decisions. The new condensate monitoring system is presently fully functional. The project has successfully achieved the objective of controlling the risk of condenser in-leakage events and minimising damage and negative effects on the plant.
93

Otahuhu B Power Station condenser in-leakage analysis and condensate monitoring system : a thesis presented in partial fulfilment of the requirements for the degree of Master of Engineering in Electronics Engineering at Massey University, Wellington, New Zealand

Zhang, Heng January 2008 (has links)
Considerable ongoing risk of condenser in-leakage exists at Otahuhu B (OTB) Power Station. The condenser cooling water used at OTB station is corrosive brackish water with exceedingly high sodium and chloride concentrations. Significant signs of corrosion inside the condenser have been found recently. In the event of condenser in-leakage, the salt contaminants in the cooling water will directly enter the Heat Recovery Steam Generator (HRSG) with the potential for significant and costly damage resulting in a long plant outage. A dynamic mathematical model was developed in the thesis to analyse the consequences of condenser in-leakage at OTB station. The analysis results show that the tolerance of the condenser to any leakage of cooling water is almost zero. Because the existing condensate monitoring system is not designed to detect contamination in this time frame, a new fast response system is required to detect condenser in-leakage immediately. A new dedicated fast response condensate monitoring system has been engineered and installed at OTB station as a part of the project scope. The new system dramatically reduces the response time to condenser in-leakage events. Critical instruments utilise multiple redundancy schemes to enhance the availability and reliability of the system. In addition, action level voting, timing, and alarming has been automated to assist operators in making correct decisions. The new condensate monitoring system is presently fully functional. The project has successfully achieved the objective of controlling the risk of condenser in-leakage events and minimising damage and negative effects on the plant.
94

Development of an acoustic emission waveguide-based system for monitoring of rock slope deformation mechanisms

Codeglia, Daniela January 2017 (has links)
Hundreds of thousands of landslides occur every year around the world impacting on people's lives. Monitoring techniques able to foresee imminent collapse and provide a warning in time useful for action to be taken are essential for risk reduction and disaster prevention. Acoustic emission (AE) is generated in soil and rock materials by rearrangement of particles during displacement or increasing damage in the microstructure preceding a collapse; therefore AE is appropriate for estimation of slope deformation. To overcome the high attenuation that characterise geological materials and thus to be able to monitor AE activity, a system called Slope ALARMS that makes use of a waveguide to transmit AE waves from a deforming zone to a piezoelectric transducer was developed. The system quantifies acoustic activity as Ring Down Count (RDC) rates. In soil applications RDC rates have been correlated with the rate of deformation, however, the application to rock slopes poses new challenges over the significance of the measured AE trends, requiring new interpretation strategies. In order to develop new approaches to interpret acoustic emission rates measured within rock slopes, the system was installed at two trial sites in Italy and Austria. RDC rates from these sites, which have been measured over 6 and 2.5 years respectively, are analysed and clear and recurring trends were identified. The comparison of AE trends with response from a series of traditional instruments available at the sites allowed correlation with changes in external slope loading and internal stress changes. AE signatures from the limestone slope at the Italian site have been identified as generated in response to variations in the groundwater level and snow loading. At the conglomerate slope in Austria, AE signatures include the detachment of small boulders from the slope surface caused by the succession of freeze-thaw cycles during winter time. Consideration was also given to laboratory testing of specific system elements and field experiments. A framework towards strategies to interpret measured acoustic emission trends is provided for the use of the system within rock slopes.
95

Dimensionality Reduction for Commercial Vehicle Fleet Monitoring

Baldiwala, Aliakbar 25 October 2018 (has links)
A variety of new features have been added in the present-day vehicles like a pre-crash warning, the vehicle to vehicle communication, semi-autonomous driving systems, telematics, drive by wire. They demand very high bandwidth from in-vehicle networks. Various electronic control units present inside the automotive transmit useful information via automotive multiplexing. Automotive multiplexing allows sharing information among various intelligent modules inside an automotive electronic system. Optimum functionality is achieved by transmitting this data in real time. The high bandwidth and high-speed requirement can be achieved either by using multiple buses or by implementing higher bandwidth. But, by doing so the cost of the network and the complexity of the wiring in the vehicle increases. Another option is to implement higher layer protocol which can reduce the amount of data transferred by using data reduction (DR) techniques, thus reducing the bandwidth usage. The implementation cost is minimal as only the changes are required in the software and not in hardware. In our work, we present a new data reduction algorithm termed as “Comprehensive Data Reduction (CDR)” algorithm. The proposed algorithm is used for minimization of the bus utilization of CAN bus for a future vehicle. The reduction in the busload was efficiently made by compressing the parameters; thus, more number of messages and lower priority messages can be efficiently sent on the CAN bus. The proposed work also presents a performance analysis of proposed algorithm with the boundary of fifteen compression algorithm, and Compression area selection algorithms (Existing Data Reduction Algorithm). The results of the analysis show that proposed CDR algorithm provides better data reduction compared to earlier proposed algorithms. The promising results were obtained in terms of reduction in bus utilization, compression efficiency, and percent peak load of CAN bus. This Reduction in the bus utilization permits to utilize a larger number of network nodes (ECU’s) in the existing system without increasing the overall cost of the system. The proposed algorithm has been developed for automotive environment, but it can also be utilized in any applications where extensive information transmission among various control units is carried out via a multiplexing bus.
96

Desenvolvimento de método e ferramenta para aplicação submarina de clamps de reparo de dutos ou proteção de sistemas de monitoramento

Bertoldi, Evandro January 2018 (has links)
O escoamento entre o poço marítimo e a unidade flutuante é realizado através de dutos definidos como risers. Os risers flexíveis são compostos por camadas intercaladas de diferentes materiais, como aço e polietileno, o qual cada camada possui uma função. Os mecanismos de falha mais reportados são referentes a danos na camada externa polimérica, o que leva à exposição de suas armaduras metálicas ao meio externo. Os risers rígidos são dutos fabricados normalmente em aço, formados por segmentos de dutos unidos por soldas, onde a causa de dano mais frequente é a corrosão. Tem-se como objetivo nesta dissertação, o projeto e desenvolvimento de uma ferramenta e de um método para operações submarinas em risers. A ferramenta deverá ser capaz de aplicar de forma automática, um clamp bipartido no reparo da camada externa polimérica de risers flexíveis, ou acoplar sistemas de monitoramento em risers rígidos. Já o método, deverá permitir a sua aplicação tanto no reparo quanto na proteção do sistema de monitoramento. Para isto, realizou-se uma revisão bibliográfica a fim de obter uma melhor compreensão sobre o tema estudado. Desenvolveu-se o projeto do método e da ferramenta, e, posteriormente, construiu-se o protótipo para a realização de testes de funcionamento em um duto rígido Por último, através de ensaios hidrostáticos de pressão interna e externa, realizaram-se ensaios para avaliação do comportamento do método aplicado em um duto rígido. Os ensaios comprovaram a eficácia do clamp quando aplicado em ambientes submarinos em grandes profundidades, porém apresentou vazamentos nos ensaios de pressão interna e externa. A resina epóxi utilizada não garantiu a estanqueidade, possivelmente devido a sua alta rigidez, aderência ineficaz em superfícies metálicas, ou presença de vazios ou porosidades. O ensaio de pressão interna indicou que as deformações não ultrapassaram o regime elástico tanto do duto quanto do clamp até aproximadamente 182 bar de pressão. No regime elástico, o ensaio apresentou deformações menores no clamp em relação ao duto, possivelmente porque a resina acabou absorvendo as deformações. O método demonstrou ser eficiente como recipiente para a resina, e também permitiu a montagem e fixação de um colar de sensores no seu interior. Os testes de funcionamento mostraram que a ferramenta projetada e construída mostrou-se adequada para a aplicação automática de um clamp bipartido em risers, e o método mostrou-se adequado para sua aplicação em risers, tanto no reparo quanto na proteção do sistema de monitoramento. / The drain between the maritime oil well and the floating unit is made trough pipes, which is defined as risers. The flexible risers are composed by alternate layers from different materials as steel and polyethylene, each layer has its function. The failure mechanisms more reported are referent to the damage in the external polymeric layer which leads to the exposition of the metal armature to the outside. The rigid risers are pipes usually fabricated in steel made by ducts segments connect by spot welding, where the most common damage is corrosion. This essay aims to project and create a tool and a method for submarine operations in risers. The tool must be able to apply, in an automatic way, a bipartite clamp in the repair of the flexible rises in external polymeric layer or to attach monitoring systems to the rigid risers. The method must allow its application in the repair as much as the monitoring system protection. For this, it was made a bibliographic review to obtain a better comprehension from the studied theme. A project from the method and a tool were developed, later a prototype was built to make the operation tests in a rigid pipe. At last, by internal and external pressure hydrostatic trials, were made tests to evaluate the behavior of the method applied in a rigid pipe The trials proved the efficiency of the clamps when applied in submarine environments and in depth; however there were leaks in the internal and external pressure tests. The Epóxi resin did not guarantee the leak-tightness, possible due to its hardness, ineffective adherence in metal surfaces or presence of gaps and porosities. The internal pressure trial indicated that the deformations did not exceed the elastic regime in the pipe as in the clamp until, about 182 pressure bar. In the elastic regime, the trial presented minor deformation in the clamps related to the pipe possibly, because the resin absorbed the deformation. The method has proven efficient as recipient for the resin and also allowed the assembly and fixation of a sensor collar in its interior. The operation tests showed that the designed and built tool is proper for an automatic bipartite clamp application in risers and the method has proven proper for its application in risers in repair as much as monitoring system protection.
97

Desenvolvimento de método e ferramenta para aplicação submarina de clamps de reparo de dutos ou proteção de sistemas de monitoramento

Bertoldi, Evandro January 2018 (has links)
O escoamento entre o poço marítimo e a unidade flutuante é realizado através de dutos definidos como risers. Os risers flexíveis são compostos por camadas intercaladas de diferentes materiais, como aço e polietileno, o qual cada camada possui uma função. Os mecanismos de falha mais reportados são referentes a danos na camada externa polimérica, o que leva à exposição de suas armaduras metálicas ao meio externo. Os risers rígidos são dutos fabricados normalmente em aço, formados por segmentos de dutos unidos por soldas, onde a causa de dano mais frequente é a corrosão. Tem-se como objetivo nesta dissertação, o projeto e desenvolvimento de uma ferramenta e de um método para operações submarinas em risers. A ferramenta deverá ser capaz de aplicar de forma automática, um clamp bipartido no reparo da camada externa polimérica de risers flexíveis, ou acoplar sistemas de monitoramento em risers rígidos. Já o método, deverá permitir a sua aplicação tanto no reparo quanto na proteção do sistema de monitoramento. Para isto, realizou-se uma revisão bibliográfica a fim de obter uma melhor compreensão sobre o tema estudado. Desenvolveu-se o projeto do método e da ferramenta, e, posteriormente, construiu-se o protótipo para a realização de testes de funcionamento em um duto rígido Por último, através de ensaios hidrostáticos de pressão interna e externa, realizaram-se ensaios para avaliação do comportamento do método aplicado em um duto rígido. Os ensaios comprovaram a eficácia do clamp quando aplicado em ambientes submarinos em grandes profundidades, porém apresentou vazamentos nos ensaios de pressão interna e externa. A resina epóxi utilizada não garantiu a estanqueidade, possivelmente devido a sua alta rigidez, aderência ineficaz em superfícies metálicas, ou presença de vazios ou porosidades. O ensaio de pressão interna indicou que as deformações não ultrapassaram o regime elástico tanto do duto quanto do clamp até aproximadamente 182 bar de pressão. No regime elástico, o ensaio apresentou deformações menores no clamp em relação ao duto, possivelmente porque a resina acabou absorvendo as deformações. O método demonstrou ser eficiente como recipiente para a resina, e também permitiu a montagem e fixação de um colar de sensores no seu interior. Os testes de funcionamento mostraram que a ferramenta projetada e construída mostrou-se adequada para a aplicação automática de um clamp bipartido em risers, e o método mostrou-se adequado para sua aplicação em risers, tanto no reparo quanto na proteção do sistema de monitoramento. / The drain between the maritime oil well and the floating unit is made trough pipes, which is defined as risers. The flexible risers are composed by alternate layers from different materials as steel and polyethylene, each layer has its function. The failure mechanisms more reported are referent to the damage in the external polymeric layer which leads to the exposition of the metal armature to the outside. The rigid risers are pipes usually fabricated in steel made by ducts segments connect by spot welding, where the most common damage is corrosion. This essay aims to project and create a tool and a method for submarine operations in risers. The tool must be able to apply, in an automatic way, a bipartite clamp in the repair of the flexible rises in external polymeric layer or to attach monitoring systems to the rigid risers. The method must allow its application in the repair as much as the monitoring system protection. For this, it was made a bibliographic review to obtain a better comprehension from the studied theme. A project from the method and a tool were developed, later a prototype was built to make the operation tests in a rigid pipe. At last, by internal and external pressure hydrostatic trials, were made tests to evaluate the behavior of the method applied in a rigid pipe The trials proved the efficiency of the clamps when applied in submarine environments and in depth; however there were leaks in the internal and external pressure tests. The Epóxi resin did not guarantee the leak-tightness, possible due to its hardness, ineffective adherence in metal surfaces or presence of gaps and porosities. The internal pressure trial indicated that the deformations did not exceed the elastic regime in the pipe as in the clamp until, about 182 pressure bar. In the elastic regime, the trial presented minor deformation in the clamps related to the pipe possibly, because the resin absorbed the deformation. The method has proven efficient as recipient for the resin and also allowed the assembly and fixation of a sensor collar in its interior. The operation tests showed that the designed and built tool is proper for an automatic bipartite clamp application in risers and the method has proven proper for its application in risers in repair as much as monitoring system protection.
98

Nätverksövervakning : En jämförelse av Sensu och op5 Monitor

Nilsson, Kristoffer, Shamoun, Ashour January 2014 (has links)
Rapporten beskriver arbetet och resultaten av en jämförelse mellan Sensu och op5 Monitor, vilka är verktyg som används för att övervaka enheter i nätverk, så kallade network monitoring systems. Arbetet har utförts för att utbudet av nätverksövervakningsverktyg ständigt växer och det ansågs värdefullt att jämföra en ny aktör med ett äldre verktyg som är byggd på ett annat tankesätt. Det som ansågs intressant att testa var hur dessa verktyg hanterade de rapporter som skapades och samlades in, om det slutgiltiga resultatet från detta skulle skilja sig åt eller inte. För att testa detta sattes en virtuell testmiljö upp, där Sensu och op5 Monitor rullade parallellt med varandra och övervakade samma system och använde sig utav samma plugin för övervakningen. Experimenten utfördes på två stycken tjänster, BIND9 samt Apache2, i och med att de två pluginen som användes var uppbyggda på olika sätt konstruerades även olika experiment. Under dessa experiment samlades information in om hur de två övervakningsverktygen hanterade de rapporter de fick in, vilket sedan sammanställdes och analyserades. Slutsatsen av det hela var att Sensu och op5 Monitor hanterar sina insamlade rapporter på ett likvärdigt sätt, de rapporterade resultaten blev i samtliga fall detsamma, således fungerade de två övervakningsverktygen på ett jämgott vis. / The report describes the work and results of a comparison between Sensu and op5 Monitor, which are both tools used to monitor devices in a network, more commonly known as network monitoring systems. The subject was chosen due to the fact that there is such a wide range of network monitoring systems, and it is constantly expanding. It was considered valuable to compare a newcomer with an older tool that is built with a different mindset. It was considered interesting to test how these tools handled the reports created and collected by them, to see if the final results from this would differ or not. To test this a virtual testing environment was built, where Sensu and op5 Monitor were run in parallel to each other and monitored the same systems and used the same set of plugins. The experiments were conducted on two services, BIND9 and Apache2, since the plugins were constructed in different ways, so were the various experiments. In these experiments information was gathered about how the two monitoring tools handled the reports they received, which was then compiled and analysed. The conclusion of it all was that Sensu and op5 Monitor handles the collected information in a similar manner. The reported results were in all cases the same, thus the two monitoring tools behave in the same fashion.
99

Předstihový kompozitní index a jeho role při analýze hospodářského cyklu v České republice během let 1993-2015 / Composite leading index and its role in the analysis of the business cycle in the Czech republic between 1993-2015

Hornová, Michaela January 2015 (has links)
The main topic of my thesis is the problem of monitoring business cycles. Composite leading indicators are one of the options, how to make this monitoring. In my thesis I am going inside of the process of construction of composite leading indicator. I am comparing the methods of OECD, Eurostat and Conference Board. Special attention is dedicated to the methods of czech institutions as well. These methods are still being evolved and improved, which makes the analysis more difficult. Together with all the information about business cycle and economic policy in Czech republic between 1993-2015. I am judgeing the functionality of leading indicators for the monitoring of business cycle. Method of my analysis is SWOT analysis so the result of this thesis is mentioning of the strengths, weaknesses, opportunities and threaths of the making and application of composite leading indicators.
100

Monitorování výrobních zařízení / Monitoring of production facilities

Borsuk, Adam January 2020 (has links)
The aim of the diploma thesis is to study the possibilities of creating a monitoring system for older production facilities already in operation. Select the necessary components for the nature of the equipment to create a system that is able to capture and provide information about activities on the equipment. The second goal is to design a suitable communication model for clear information about the operation, sending and storing data. The third goal is to analyze the dual-core ESP32 microprocessor against its predecessors in the role of system control unit.

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