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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.
1

Internet-based monitoring and controlling of real-time dynamic systems

Al Shoaili, Saoud Humaid Salim January 2005 (has links)
The study in this report mainly focuses on the Internet-based Monitoring and Controlling of a Real-Time Dynamic System interfaced via a dedicated local computer. The main philosophy behind this study is to allow the remote user to conduct an Internet-based Remote Operation (I-bRO) for the dynamic system. The dynamic system has been defined as the system which has its parts interrelated in such a way that a change in one part necessarily affects other parts of the system [I]. In order to achieve this goal, the study has been conducted in a form of an on-line and real-time Virtual Laboratory (VL). Through this form of laboratory, a user can carry out the experiment, perform real-time monitoring and controlling operations of the experiment and collect real and live data from the experiment through the network link as the user was physically in the laboratory. The dynamic system that has been selected for the test-rig of this study is a 3-phase Induction Motor (IM) which is mechanically coupled with a DC-Dynamometer that acts as a variable load to the IM. This system is a common laboratory experiment in the study of the Electrical Engineering for both undergraduate and postgraduate students. The study covers both sides of the I-bRO; the hardware and the software. The hardware side includes the design and the development of a load control box that has been used to interface the DC-Dynamometer and consequently control it from the local computer. The software side covers the design and the development of the Virtual Instrumentation System (VIS) that has replaced successfully the physical Measurement and Test (M&T) instruments of the test-rig. Beside that, the software side includes the development of the internet remote front panel for the remote operation. / Furthermore, the software side includes the development of the software that has been used to analyse the system during the I-bRO. In this study, the LabVTEW7 program has been used to design and develop the VIS and the Matlab program has bee used to aualyse the system performance for the remote operations. This study also addresses the issues and problems related to the intranet or the internet to be used as the network for data communication between the test-rig and remote users. This study has been carried out in different stages as follows: 1. Designing and development of the VIS. 2. Interfacing the test-rig apparatus with a local computer. 3. Upload the system from the local computer to the network. 4. Study the performance of the system on the network for the purpose of the remote operations controlled over the internet. The developed system of this study has been used for data acquisition, network communications, instruments monitoring and controlling applications. A user can execute on-line and in the real-time the developed VIS from any point in the university. Due to the fact that the university network is directly integrated to the main internet server. a remote user through the main internet server is able to perform I-bRO of the selected dynamic system. There are many factors associated with the network, the internet or the intranet, and have direct influences on the control system performance throughout the remote operations. The most dominant factors are the random time-delays and the data losses. / These factors among others have to be addressed for a proper application of the I-bRO. For this reason, different cases and scenarios of the I-bRO have been investigated and simulated to study the affection of the network on the control system performance. The system is analysed under two control cases, closed loop with random time-delays and open loop when the internet server is disconnected and no communication between the input and the output of the system. In the first case, the closed loop, the internet server is assumed to be closed and subjected to random time-delays. In the second case, the internet server is subjected to random cut-off and thus opens the control loop. The results of both cases have been analysed and discussed. It has been found that, if the control system without the time-delays is stable, it remains stable even with small time-delays up to twenty seconds. This result is different from what has been shown in the literature.
2

Modeling Management Metrics for Monitoring Software Systems

Jiang, Miao January 2011 (has links)
Software systems are growing rapidly in size and complexity, and becoming more and more difficult and expensive to maintain exclusively by human operators. These systems are expected to be highly available, and failure in these systems is expensive. To meet availability and performance requirements within budget, automated and efficient approaches for systems monitoring are highly desirable. Autonomic computing is an effort in this direction, which promises systems that self-monitor, thus alleviating the burden of detailed operation oversight from human administrators. In particular, a solution is to develop automated monitoring systems that continuously collect monitoring data from target systems, analyze the data, detect errors and diagnose faults automatically. In this dissertation, we survey work based on management metrics and describe the common features of these current solutions. Based on observations of the advantages and drawbacks of these solutions, we present a general solution framework in four separate steps: metric modeling, system-health signature generation, system-state checking, and fault localization. Within our framework, we present two specific solutions for error detection and fault diagnosis in the system, one based on improved linear-regression modeling and the second based on summarizing the system state by an informationtheoretic measurement. We evaluate our monitoring solutions with fault-injection experiments in a J2EE benchmark and show the effectiveness and efficiency of our solutions.
3

Modeling Management Metrics for Monitoring Software Systems

Jiang, Miao January 2011 (has links)
Software systems are growing rapidly in size and complexity, and becoming more and more difficult and expensive to maintain exclusively by human operators. These systems are expected to be highly available, and failure in these systems is expensive. To meet availability and performance requirements within budget, automated and efficient approaches for systems monitoring are highly desirable. Autonomic computing is an effort in this direction, which promises systems that self-monitor, thus alleviating the burden of detailed operation oversight from human administrators. In particular, a solution is to develop automated monitoring systems that continuously collect monitoring data from target systems, analyze the data, detect errors and diagnose faults automatically. In this dissertation, we survey work based on management metrics and describe the common features of these current solutions. Based on observations of the advantages and drawbacks of these solutions, we present a general solution framework in four separate steps: metric modeling, system-health signature generation, system-state checking, and fault localization. Within our framework, we present two specific solutions for error detection and fault diagnosis in the system, one based on improved linear-regression modeling and the second based on summarizing the system state by an informationtheoretic measurement. We evaluate our monitoring solutions with fault-injection experiments in a J2EE benchmark and show the effectiveness and efficiency of our solutions.
4

Desenvolvimento de sistema para monitoramento de estruturas com utiliza??o da plataforma arduino

Silva, Jo?o Batista Lamari Palma 09 October 2018 (has links)
Submitted by SBI Biblioteca Digital (sbi.bibliotecadigital@puc-campinas.edu.br) on 2018-12-12T11:03:02Z No. of bitstreams: 1 Joao Batista Lamari Palma e Silva.pdf: 6384826 bytes, checksum: 7f07e131301eff9f4bf2ddb19d173b2b (MD5) / Made available in DSpace on 2018-12-12T11:03:02Z (GMT). No. of bitstreams: 1 Joao Batista Lamari Palma e Silva.pdf: 6384826 bytes, checksum: 7f07e131301eff9f4bf2ddb19d173b2b (MD5) Previous issue date: 2018-10-09 / The structures of reinforced concrete, although extremely diffused, require special attention from its conception, utilization its operation. This kind of attention could contribute for developing more useful time of usage, as since, the pathologies could be most varieties in complexes conditions, and so far is to analyze the integrity of the complexity of the structural condition. Structural Heart Monitoring (SHM) seeks the process of monitoring the behavior of the structure in order to assess the structure's conditions verifying the occurrence of damages and eventually in case of need for interventions, aiming at structural rehabilitation. The automated SHM uses data acquisition which acts as an interface between the sensors installed in the structures and the computational systems could be very complex and expensive. This work had the initiative to use the Arduino platform, which one is an electronic prototyping system, which uses an Atmel microcontroller, free hardware and software, with Analog/Digital inputs and outputs, low cost and relative ease of operation. The objective of this research was the development of a structure monitoring system, based on data collection from strain, displacement and force sensors, on reinforced concrete structures, for the acquisition and remote transmission of data, for processing and analysis of information. A data acquisition system was built with the Arduino platform, and this system has been used besides the platform in question, signal amplifiers and Wheatstone Bridge type circuits. A mobile application as a type of software has been developed, compatible with the Android operating system, through a smartphone or tablet, it was possible to control the Arduino through wireless communication via Bluetooth. This application sends and receives data, which is processed and analyzed analytically and graphically, resulting from the information of the sensors installed in the structures, which enables the transmission of the data in real time, via the internet. This system was tested in bending tests of metallic cantilever and reinforced concrete beams, instrumented with electric resistance strain gauges installed in the reinforcement and concrete, as displacement transducers and load cells. In addition to this structure, the system was also tested on a reinforced concrete column supporting a crane, with the installation of strain gauges in the reinforcement. In these tests, the data acquisition was made by two different systems, the first one being a commercial data acquisition purchaser and the second the system object of this research, to compare the data of the readings, obtained between both equipment and analytical values, establishing satisfactory results. / As estruturas de concreto armado, ainda que extremamente difundidas, requerem especial aten??o desde sua concep??o at? sua utiliza??o. Esta aten??o pode ser usada para contribuir com o aumento de sua vida ?til, j? que as patologias podem ser das mais variadas naturezas e causas, o que em muitas vezes torna a an?lise das condi??es de integridade estrutural muito complexa. O Monitoramento da Integridade Estrutural (MIE) busca acompanhar o comportamento da estrutura, para avaliar suas condi??es, inclusive para verificar a ocorr?ncia de danos e das eventuais necessidades de interven??es, visando a reabilita??o estrutural. O MIE automatizado emprega aquisitores de dados que atuam como interface entre os sensores instalados nas estruturas e os sistemas computacionais, tornando sua utiliza??o complexa e cara. Este trabalho teve por iniciativa empregar a plataforma Arduino, que ? um sistema de prototipagem eletr?nica, que utiliza um microcontrolador Atmel, de hardware e software livres, com entradas e sa?das anal?gicas/digitais, de baixo custo e relativa facilidade de opera??o. Com isto, o objetivo da pesquisa foi o desenvolvimento de um sistema de monitoramento de estruturas, baseado em coleta de dados provenientes de sensores de deforma??o, deslocamento e for?a, em estruturas de concreto armado, para aquisi??o e transmiss?o remota de dados, para processamento e an?lise das informa??es. Foi constru?do um sistema de aquisi??o de dados, com a plataforma Arduino, sendo que este sistema emprega al?m da plataforma em quest?o, amplificadores de sinais e circuitos el?tricos do tipo Ponte de Wheatstone. Desenvolveu-se um software do tipo aplicativo mobile, compat?vel com o sistema operacional Android, para que por meio de um smartphone ou tablet, fosse poss?vel controlar o Arduino, mediante comunica??o sem fio via Bluetooth. Este aplicativo envia e recebe dados, que s?o processados e analisados anal?tica e graficamente, decorrentes das informa??es dos sensores instalados nas estruturas, o qual possibilita a transmiss?o dos dados em tempo real via internet. O sistema foi testado em ensaios de flex?o de l?minas met?licas e vigas de concreto armado, instrumentadas com extens?metros de resist?ncia el?trica instalados na armadura e no concreto, como transdutores de deslocamento e c?lulas de carga. Al?m desta estrutura, o sistema tamb?m foi testado em um pilar de concreto armado de sustenta??o de uma ponte rolante, com a instala??o de extens?metros na armadura. Nestes testes, a aquisi??o de dados foi feita por dois sistemas distintos, sendo o primeiro um aquisitor de dados comercial de refer?ncia e o segundo o sistema objeto desta pesquisa, para compara??o dos dados das leituras obtidas entre ambos equipamentos e valores anal?ticos, tendo sido obtidos resultados satisfat?rios.
5

Optimal fault location

Knezev, Maja 15 May 2009 (has links)
Basic goal of power system is to continuously provide electrical energy to the users. Like with any other system, failures in power system can occur. In those situations it is critical that correct remedial actions are applied as soon as possible after the accurate fault condition and location are detected. This thesis has been focusing on automated fault location procedure. Different fault location algorithms, classified according to the spatial placement of physical measurements on single ended, multiple ended and sparse system-wide, are investigated. As outcome of this review, methods are listed as function of different parameters that influence their accuracy. This comparison is than used for generating procedure for optimal fault location algorithm selection. According to available data, and position of the fault with respect to the data, proposed procedure decides between different algorithms and selects an optimal one. A new approach is developed by utilizing different data structures such as binary tree and serialization in order to efficiently implement algorithm decision engine. After accuracy of algorithms is strongly influenced by available input data, different data sources are recommended in proposed architecture such as the digital fault recorders, circuit breaker monitoring, SCADA, power system model and etc. Algorithm for determining faulted section is proposed based on the data from circuit breaker monitoring devices. This algorithm works in real time by recognizing to which sequence of events newly obtained recording belongs. Software prototype of the proposed automated fault location analysis is developed using Java programming language. Fault location analysis is automatically triggered by appearance of new event files in a specific folder. The tests were carried out using the real life transmission system as an example.
6

Optimal fault location

Knezev, Maja 10 October 2008 (has links)
Basic goal of power system is to continuously provide electrical energy to the users. Like with any other system, failures in power system can occur. In those situations it is critical that correct remedial actions are applied as soon as possible after the accurate fault condition and location are detected. This thesis has been focusing on automated fault location procedure. Different fault location algorithms, classified according to the spatial placement of physical measurements on single ended, multiple ended and sparse system-wide, are investigated. As outcome of this review, methods are listed as function of different parameters that influence their accuracy. This comparison is than used for generating procedure for optimal fault location algorithm selection. According to available data, and position of the fault with respect to the data, proposed procedure decides between different algorithms and selects an optimal one. A new approach is developed by utilizing different data structures such as binary tree and serialization in order to efficiently implement algorithm decision engine. After accuracy of algorithms is strongly influenced by available input data, different data sources are recommended in proposed architecture such as the digital fault recorders, circuit breaker monitoring, SCADA, power system model and etc. Algorithm for determining faulted section is proposed based on the data from circuit breaker monitoring devices. This algorithm works in real time by recognizing to which sequence of events newly obtained recording belongs. Software prototype of the proposed automated fault location analysis is developed using Java programming language. Fault location analysis is automatically triggered by appearance of new event files in a specific folder. The tests were carried out using the real life transmission system as an example.
7

Assesment of drinking water quality using disinfection by-products in a distribution system following a treatment technology upgrade

Bush, Kelly Lynn 05 1900 (has links)
Chlorine is the most widely used disinfectant for drinking water treatment. Chlorine canreact with natural organic matter (NOM) in water sources resulting in the formation of potentially carcinogenic disinfection by-products (DBPs). The most common DBPs measured in chlorinated drinking water distribution systems are trihalomethanes (THMs) and haloacetic acids (HAAs). In 2005, the City of Kamloops, British Columbia upgraded the drinking water treatment system to ultrafiltration membrane treatment. The objective of this study was to determine the extent to which upgrades to a drinking water treatment system, specifically, implementation of an ultrafiltration treatment process, impacted DBP formation within a distribution system. This study used a two-phase research approach. Phase I of the study was a distribution system monitoring program that collected water samples and physical and chemical information using data loggers at five sampling sites within the distribution system. Phase II of the study used bench-scale simulations that modeled DBP formation using a flow-through reactor system, the material-specific simulated distribution system (MS-SDS), constructed of pipe material resurrected from the City of Kamloops distribution system. Phase I results suggested that implementation of the ultrafiltration treatment process and accompanying treatment system upgrade was not effective at reducing the concentration of DBPs delivered to consumers. Concentrations of THMs remained relatively constant at sampling sites, while concentrations of HAAs increased following implementation of the ultrafiltration treatment process. The increase in HAA formation was likely due to an increase in retention time of the water within the distribution system following implementation of the ultrafiltration treatment process, rather than due to the treatment process itself. The results of this study are consistent with previous work on South Thompson River water DBP precursors, which suggested that THM and HAA precursors of this source water are small and hydrophilic, and therefore cannot be removed by ultrafiltration processes. Phase II results showed that the MS-SDS was more representative of distribution system c onditions than traditional glass bottles to estimate DBP formation. It is recommended that the MS-SDS be used in parallel with a simultaneous distribution system monitoring program to estimate distribution system retention times from THM and HAA concentrations.
8

Assesment of drinking water quality using disinfection by-products in a distribution system following a treatment technology upgrade

Bush, Kelly Lynn 05 1900 (has links)
Chlorine is the most widely used disinfectant for drinking water treatment. Chlorine canreact with natural organic matter (NOM) in water sources resulting in the formation of potentially carcinogenic disinfection by-products (DBPs). The most common DBPs measured in chlorinated drinking water distribution systems are trihalomethanes (THMs) and haloacetic acids (HAAs). In 2005, the City of Kamloops, British Columbia upgraded the drinking water treatment system to ultrafiltration membrane treatment. The objective of this study was to determine the extent to which upgrades to a drinking water treatment system, specifically, implementation of an ultrafiltration treatment process, impacted DBP formation within a distribution system. This study used a two-phase research approach. Phase I of the study was a distribution system monitoring program that collected water samples and physical and chemical information using data loggers at five sampling sites within the distribution system. Phase II of the study used bench-scale simulations that modeled DBP formation using a flow-through reactor system, the material-specific simulated distribution system (MS-SDS), constructed of pipe material resurrected from the City of Kamloops distribution system. Phase I results suggested that implementation of the ultrafiltration treatment process and accompanying treatment system upgrade was not effective at reducing the concentration of DBPs delivered to consumers. Concentrations of THMs remained relatively constant at sampling sites, while concentrations of HAAs increased following implementation of the ultrafiltration treatment process. The increase in HAA formation was likely due to an increase in retention time of the water within the distribution system following implementation of the ultrafiltration treatment process, rather than due to the treatment process itself. The results of this study are consistent with previous work on South Thompson River water DBP precursors, which suggested that THM and HAA precursors of this source water are small and hydrophilic, and therefore cannot be removed by ultrafiltration processes. Phase II results showed that the MS-SDS was more representative of distribution system c onditions than traditional glass bottles to estimate DBP formation. It is recommended that the MS-SDS be used in parallel with a simultaneous distribution system monitoring program to estimate distribution system retention times from THM and HAA concentrations.
9

Speech as a surrogate marker of central nervous system function: practical, experimental and statistical considerations

Vogel, Adam P. January 2010 (has links)
The speech of an individual conveys a great deal of information about how their central nervous system (CNS) is performing. Whether they are tired, distressed or suffering from a degenerative disease affecting the brainstem, speech can change as a function of an individual’s condition. Yet, when assessing the speech in an individual on the first occasion, it is often difficult to determine whether their performance is different from a pre-morbid level. Therefore, the repeated acquisition and analysis of a set of brief and simple speech measures could provide information on changes in a patient’s performance over time. This could ultimately lead to the inclusion of objective markers of change in trials of conditions and disorders that currently rely of subjective, clinician derived measures of severity or patient self report, such as pain, depression or fatigue. Furthermore, the information could be used to track patient performance in treatment trials for degenerative disorders, such as Friedreich ataxia or Huntington’s disease. / This thesis aimed to evaluate the practical, experimental and statistical requirements of speech assessment protocols designed to monitor patient performance over time. The research involved a number of studies evaluating methods for acquiring and analysing data, studies examining the stability and sensitivity of speech stimuli, and finally, the functionality of these findings in an experimental model known to induce change in CNS function (i.e., sustained wakefulness). / Methods for acquiring and analysing speech data were designed to provide a balance between the concurrent demands for precision and useability inherent in repeated assessment protocols. Data from these studies provided evidence that techniques offering high levels of useability (e.g., easy to use, automated) are capable of offering adequate precision on broad acoustic measures of timing and frequency. Moreover, these methods could be standardised and automated, allowing non-expert users to collect and analyse data in a controlled and time efficient manner. The second series of experiments systematically documented the stability and responsiveness of speech stimuli within a variety of experimental conditions. These studies were designed to establish the suitability of select speech measures for monitoring change in individuals over time, as stimuli that proved to be both stable (across several re-test intervals) and sensitive to change or impairment were ideal candidates. Finally, a proof of concept study designed to evaluate the efficiency and sensitivity of the proposed methodology was initiated in an experimental model known to induce changes in psychomotor functioning in healthy adults (sustained wakefulness). Significant changes from baseline were observed in speech production as a function of increasing levels of fatigue. These findings are important as they demonstrate the potential of speech as a valid, reliable and sensitive marker of change in conditions where the CNS is subject to stress.
10

Speech as a surrogate marker of central nervous system function: practical, experimental and statistical considerations

Vogel, Adam P. January 2010 (has links)
The speech of an individual conveys a great deal of information about how their central nervous system (CNS) is performing. Whether they are tired, distressed or suffering from a degenerative disease affecting the brainstem, speech can change as a function of an individual’s condition. Yet, when assessing the speech in an individual on the first occasion, it is often difficult to determine whether their performance is different from a pre-morbid level. Therefore, the repeated acquisition and analysis of a set of brief and simple speech measures could provide information on changes in a patient’s performance over time. This could ultimately lead to the inclusion of objective markers of change in trials of conditions and disorders that currently rely of subjective, clinician derived measures of severity or patient self report, such as pain, depression or fatigue. Furthermore, the information could be used to track patient performance in treatment trials for degenerative disorders, such as Friedreich ataxia or Huntington’s disease. / This thesis aimed to evaluate the practical, experimental and statistical requirements of speech assessment protocols designed to monitor patient performance over time. The research involved a number of studies evaluating methods for acquiring and analysing data, studies examining the stability and sensitivity of speech stimuli, and finally, the functionality of these findings in an experimental model known to induce change in CNS function (i.e., sustained wakefulness). / Methods for acquiring and analysing speech data were designed to provide a balance between the concurrent demands for precision and useability inherent in repeated assessment protocols. Data from these studies provided evidence that techniques offering high levels of useability (e.g., easy to use, automated) are capable of offering adequate precision on broad acoustic measures of timing and frequency. Moreover, these methods could be standardised and automated, allowing non-expert users to collect and analyse data in a controlled and time efficient manner. The second series of experiments systematically documented the stability and responsiveness of speech stimuli within a variety of experimental conditions. These studies were designed to establish the suitability of select speech measures for monitoring change in individuals over time, as stimuli that proved to be both stable (across several re-test intervals) and sensitive to change or impairment were ideal candidates. Finally, a proof of concept study designed to evaluate the efficiency and sensitivity of the proposed methodology was initiated in an experimental model known to induce changes in psychomotor functioning in healthy adults (sustained wakefulness). Significant changes from baseline were observed in speech production as a function of increasing levels of fatigue. These findings are important as they demonstrate the potential of speech as a valid, reliable and sensitive marker of change in conditions where the CNS is subject to stress.

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