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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.
21

Development and initial evaluation of wireless self-monitoring pneumatic compression sleeves for preventing deep vein thrombosis in surgical patients

Cheung, William Ka Wai 05 1900 (has links)
This thesis describes the successful development and initial evaluation of a proof-of-concept wireless monitoring system for improving the effectiveness and safety of pneumatic compression therapy to help prevent deep vein thrombosis (DVT). In the development, an important objective was to make feasible the practical and commercial deployment of such improved therapy systems in future, by focusing on a cost-effective design and implementation. Over the years, pneumatic compression has been shown to be an effective solution for the prevention of DVT. However, different problems and complications related to the use of commercial pneumatic compression de-vices that typically include automatic pressure controllers and pneumatic compression sleeves have been reported. For example, one study reported a high percentage of improperly applied or nonfunctional pneumatic compression devices in routine usage. Technical problems, non-compliance, and human error were identified as the causes behind the failed therapies. Also, it was reported that dedicated in-service instruction did not improve the proper use of the pneumatic compression controllers and sleeves. In another study, significant unanticipated variations between expected and delivered pneumatic compression therapy were reported: expected therapy delivered only an average of 77.8% of the time during the therapy, and much of the time key values related to the outcome of the therapy were found to have variations great than 10%. Specific hazards have also been reported. For example, one patient developed acute compartment syndrome after wearing a pair of pneumatic compression sleeves with faulty pressure release valves. In another case, epidural analgesia masked a malfunction resulting from a reversed connection between four-way plastic tubing of the sleeves and the controller, exposing a patient to a hazardous pressure of around 300mmHg,blocking all blood flow for a prolonged period of time. Newer models of pneumatic compression sleeves and controllers from various manufacturers claim to improve therapy by, for example, increasing the peak blood flow velocity. However, there is no evidence in the published literature to support such claims. A published review of the literature from1970-2002 reached the conclusion that the most important factors in im-proving therapy with pneumatic compression devices, particularly during and after surgery, were the degree of conformance of delivered therapy to the prescribed therapy, patient compliance, and the appropriateness of the site of compression. The inability to monitor delivered therapy and patient compliance remains a problem in efforts to improve pneumatic compression therapy. The above-described problems were addressed in the successful development of the innovative prototype described in this thesis. This wireless monitoring system should improve the effectiveness and safety of pneumatic compression therapy. Also, innovative aspects of the system design allow for cost-effective integration into existing commercial controllers and sleeves. For example, an innovative and potentially patentable usage and reprocess indicator was developed for pneumatic compression sleeves to significantly improve their safety and to reduce their cost of use per patient.
22

Towards a mobile user interface used for monitoring purposes in context of a Geographical Information System

Hajdinjak, Matic January 2013 (has links)
Mobile Geographical Information Systems are becoming a more and more important tool for presenting geographical data. They are used to support decision making processes, present an overview of distributed information or are in a form of location based services. The problem lies in the fact that mobile devices have limited resources and should still be able to present massive amounts of content. Ideally, the user and the conditions in which the program runs are well defined, but this is usually not the case. This thesis provides a sample prototype implementation of a mobile GIS developed as an alternative to an existing web-based user interface (UI). It focuses on specific conditions present on mobile devices, ways of presenting the data and possibilities of reusing existing elements from the web UI that could be suitable for the mobile environment.
23

Gas Turbine Monitoring System

Ozmen, Teoman 01 December 2006 (has links) (PDF)
In this study, a new gas turbine monitoring system being able to carry out appropriate run process is set up for a gas turbine with 250 kW power rating and its accessories. The system with the mechanical and electrical connections of the required sub-parts is transformed to a kind of the test stand. Performance test result calculation method is described. In addition that, performance evaluation software being able to apply with the completion of the preliminary performance tests is developed for this gas turbine. This system has infrastructure for the gas turbine sub-components performance and aerothermodynamics research. This system is also designed for aviation training facility as a training material for the gas turbine start and run demonstration. This system provides the preliminary gas turbine performance research requirements in the laboratory environment.
24

A Monitoring System for Performance Evaluation of Hand Motor Task in Functional MRI Environment

Huang, Qun-Hao 26 June 2003 (has links)
Abstract In this dissertation, we aim to study the acupuncture effect on stroke rehabilitation. To achieve this purpose, a monitoring system for performance evaluation of motor task in functional MRI environment is developed. The hypothesis of the clinical study is that acupuncture stimulation at motor zone of scalp acupoint could modulate the brain activation of motor system. Such modulation effect can be explored by fMRI. So we use the monitoring system can be used to observe patients with predominantly motor deficit without remarkable speech problem. Besides the fMRI findings of motor activation and clinical motor performance will be compared. The monitoring system must be magnetic field compatible, and furthermore, it can also detect very subtle motor performance in the case of stroke during recovery. So the specific requirements of the system challenge the need. The system includes two subsystems. One collects the position signal using a data glove and the other acquires the force signal with a pneumatic system. The understanding of the correlation of the motor task and the brain activation in depth through the integration of the position and force data can therefore be greatly improved. The monitoring system will extend to be the estimation of recovery through the integration of motor task and fMRI. Keyword: functional MRI¡Bmonitoring system¡Bmotor task¡Bforce measurement
25

Park hunt : an optimized approach to implement and deploy parking monitoring systems in open environments / Optimized approach to implement and deploy parking monitoring systems in open environments

Siddiqui, Fahd Murtuza 27 February 2012 (has links)
The time consuming, tedious, and, sometimes, never ending search for a parking spot is a matter of common experience. We present an innovative approach to parking monitoring systems that only requires sensors at the entry and exit points of a street segment in an open environment such as a city downtown (as opposed to a closed environment such as a parking garage/lot). It can be trivially understood that using this set-up we can determine the number of vehicles present in a given street segment at any given time. However, the bigger issue is to closely estimate how many of those vehicles are parked or en route. We present an algorithm by which we can have a practical estimate of parked cars without introducing any more sensors. We further present a self-stabilizing system that can be implemented for fault tolerance and a few other methods to mitigate errors that may accrue over time. Our approach is based on the assumption that drivers do not care about the exact location of the parking spot, as long as they know the “street segment” where parking is available. For example, just letting the users know of available parking on 7th street between Red River and Brazos gives them enough information to easily find a parking spot. This type of information would most likely be shown on a map. Once the driver reaches the correct street area, it is easy to locate an empty parking spot. Finally, to test and evaluate our approach, we developed and deployed an embedded system using ultra-sonic sensors, and a Microsoft Bing Map application with the said user interface, along with an interoperable web service that can provide parking information to any third party application. / text
26

Development and initial evaluation of wireless self-monitoring pneumatic compression sleeves for preventing deep vein thrombosis in surgical patients

Cheung, William Ka Wai 05 1900 (has links)
This thesis describes the successful development and initial evaluation of a proof-of-concept wireless monitoring system for improving the effectiveness and safety of pneumatic compression therapy to help prevent deep vein thrombosis (DVT). In the development, an important objective was to make feasible the practical and commercial deployment of such improved therapy systems in future, by focusing on a cost-effective design and implementation. Over the years, pneumatic compression has been shown to be an effective solution for the prevention of DVT. However, different problems and complications related to the use of commercial pneumatic compression de-vices that typically include automatic pressure controllers and pneumatic compression sleeves have been reported. For example, one study reported a high percentage of improperly applied or nonfunctional pneumatic compression devices in routine usage. Technical problems, non-compliance, and human error were identified as the causes behind the failed therapies. Also, it was reported that dedicated in-service instruction did not improve the proper use of the pneumatic compression controllers and sleeves. In another study, significant unanticipated variations between expected and delivered pneumatic compression therapy were reported: expected therapy delivered only an average of 77.8% of the time during the therapy, and much of the time key values related to the outcome of the therapy were found to have variations great than 10%. Specific hazards have also been reported. For example, one patient developed acute compartment syndrome after wearing a pair of pneumatic compression sleeves with faulty pressure release valves. In another case, epidural analgesia masked a malfunction resulting from a reversed connection between four-way plastic tubing of the sleeves and the controller, exposing a patient to a hazardous pressure of around 300mmHg,blocking all blood flow for a prolonged period of time. Newer models of pneumatic compression sleeves and controllers from various manufacturers claim to improve therapy by, for example, increasing the peak blood flow velocity. However, there is no evidence in the published literature to support such claims. A published review of the literature from1970-2002 reached the conclusion that the most important factors in im-proving therapy with pneumatic compression devices, particularly during and after surgery, were the degree of conformance of delivered therapy to the prescribed therapy, patient compliance, and the appropriateness of the site of compression. The inability to monitor delivered therapy and patient compliance remains a problem in efforts to improve pneumatic compression therapy. The above-described problems were addressed in the successful development of the innovative prototype described in this thesis. This wireless monitoring system should improve the effectiveness and safety of pneumatic compression therapy. Also, innovative aspects of the system design allow for cost-effective integration into existing commercial controllers and sleeves. For example, an innovative and potentially patentable usage and reprocess indicator was developed for pneumatic compression sleeves to significantly improve their safety and to reduce their cost of use per patient.
27

Controle de vazÃo de biogÃs com baixa pressÃo para produÃÃo descentralizada de eletricidade / Low pressure biogas flow control for decentralized electricity production

Andrà Pimentel Moreira 27 October 2011 (has links)
Banco do Nordeste do Brasil / A presente dissertaÃÃo propÃe a implementaÃÃo de um sistema de aquisiÃÃo de dados, controle e monitoramento de uma planta de geraÃÃo de energia elÃtrica acionada por biogÃs. Foi realizado o estudo experimental das estratÃgias de modelagem, identificaÃÃo e controle aplicado ao controle de vazÃo da planta de biogÃs do LaboratÃrio de Energias Alternativas - LEA da Universidade Federal do Cearà - UFC. Foi utilizado e testado para o controle de vazÃo de biogÃs o controlador PI paralelo, alÃm de realizar a comparaÃÃo com o controle existente (controle centrÃfugo) do conjunto motor/gerador. Para vericar a resposta do gerador movido a biogÃs, foi inserido uma carga correspondente a 60% da potÃncia nominal. O sistema proposto reduziu a intervenÃÃo humana no ajuste de vazÃo da vÃlvula de expansÃo. Os resultados demonstraram que o tempo de resposta para estabilidade apÃs a introduÃÃo do contolador PI ao controlador original permitiu a reduÃÃo do tempo de resposta para estabilidade em no mÃnimo 20% mostrando uma resposta satisfatÃria e boa estabilidade para a transiÃÃo da gasolina para o biogÃs, com amplitude de 10 Hz e 8 segundos para estabilizaÃÃo do sistema sem carga. A aÃÃo foi considerada viÃvel para automatizar o processo de partida do conjunto motor/gerador. / The present dissertation proposes the implementation of a data acquisition system, control and monitoring of a electricity generation plant powered by biogas. The experimental study of the modelling strategies, identication and control was done applied to ow control of the biogas plant of the Renewable Energy Laboratory - LEA at the Federal University of Cearà - UFC. To control the biogas ow a parallel PI controller was used and tested, and the controller was used to perform the comparison with the existing control (centrifugal control) of the gen-set. To check the response of the gen-set powered by biogas, a load corresponding of 60% of the nominal power was used. The proposed system reduced the human intervention in ow setting of the expansion valve. The results showed that the stability response time after the introduction of the PI controller to the original controller allowed the reduction of the response time for at least 20% showing a satisfactory response and a stability for the transition from gasoline to biogas, with 10 Hz amplitude and 8 seconds for the system stabilization with load. This action was considered feasible to automate the process of starting up of the gen-set.
28

Development and initial evaluation of wireless self-monitoring pneumatic compression sleeves for preventing deep vein thrombosis in surgical patients

Cheung, William Ka Wai 05 1900 (has links)
This thesis describes the successful development and initial evaluation of a proof-of-concept wireless monitoring system for improving the effectiveness and safety of pneumatic compression therapy to help prevent deep vein thrombosis (DVT). In the development, an important objective was to make feasible the practical and commercial deployment of such improved therapy systems in future, by focusing on a cost-effective design and implementation. Over the years, pneumatic compression has been shown to be an effective solution for the prevention of DVT. However, different problems and complications related to the use of commercial pneumatic compression de-vices that typically include automatic pressure controllers and pneumatic compression sleeves have been reported. For example, one study reported a high percentage of improperly applied or nonfunctional pneumatic compression devices in routine usage. Technical problems, non-compliance, and human error were identified as the causes behind the failed therapies. Also, it was reported that dedicated in-service instruction did not improve the proper use of the pneumatic compression controllers and sleeves. In another study, significant unanticipated variations between expected and delivered pneumatic compression therapy were reported: expected therapy delivered only an average of 77.8% of the time during the therapy, and much of the time key values related to the outcome of the therapy were found to have variations great than 10%. Specific hazards have also been reported. For example, one patient developed acute compartment syndrome after wearing a pair of pneumatic compression sleeves with faulty pressure release valves. In another case, epidural analgesia masked a malfunction resulting from a reversed connection between four-way plastic tubing of the sleeves and the controller, exposing a patient to a hazardous pressure of around 300mmHg,blocking all blood flow for a prolonged period of time. Newer models of pneumatic compression sleeves and controllers from various manufacturers claim to improve therapy by, for example, increasing the peak blood flow velocity. However, there is no evidence in the published literature to support such claims. A published review of the literature from1970-2002 reached the conclusion that the most important factors in im-proving therapy with pneumatic compression devices, particularly during and after surgery, were the degree of conformance of delivered therapy to the prescribed therapy, patient compliance, and the appropriateness of the site of compression. The inability to monitor delivered therapy and patient compliance remains a problem in efforts to improve pneumatic compression therapy. The above-described problems were addressed in the successful development of the innovative prototype described in this thesis. This wireless monitoring system should improve the effectiveness and safety of pneumatic compression therapy. Also, innovative aspects of the system design allow for cost-effective integration into existing commercial controllers and sleeves. For example, an innovative and potentially patentable usage and reprocess indicator was developed for pneumatic compression sleeves to significantly improve their safety and to reduce their cost of use per patient. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate
29

Conception et prototypage d'un système complet pour la surveillance du grain dans les silos de stockage / Design and prototyping of a complete system for grain monitoring in storage silos

Bettahar, Fehd 05 April 2016 (has links)
Cette thèse traite des nouvelles technologies de surveillance appliquées au stockage des grains en silos. Les céréales représentent depuis les premiers regroupements sédentaires l’aliment principal pour l’Homme comme pour le bétail. Les récoltes sont saisonnières et leur stockage est donc une nécessité vitale pour une population mondiale qui compte actuellement 7,2 Mds d'habitants et qui en comptera 9 Mds en 2050. Dans cette problématique autour de la surveillance des silos, les insectes représentent les premiers ravageurs de grain après récolte, ce qui entraîne des pertes considérables pouvant atteindre dans certains cas jusqu’à 10% de la production. Plusieurs techniques et méthodes ont été développées et mises en pratique afin de faire face au danger que représentent ces ravageurs. La méthode la plus répandue est l’utilisation des insecticides chimiques de synthèse dont la dangerosité, impactant tant sur la santé humaine que sur l'environnement, est plus qu'évidente. Ce travail de thèse s'inscrit dans un programme coopératif, nommé ECOSILO, dont l'objectif majeur est de concevoir et de prototyper des solutions alternatives écologiques à l'utilisation systématique et massive de produits insecticides. Il s'agit donc d'une démarche largement pluridisciplinaire dans laquelle nous avons eu en charge d'imaginer un système complet de surveillance : détection au plus tôt des infestations et commande automatique de la diffusion d'attractifs puis d'insecticides. Notre proposition est fondée sur une logique de protection intégrée et privilégie la prévention et la détection précoce d'éventuelles infestations, ce afin de préserver les stocks et d'éviter d'atteindre un stade de perte économique trop élevé. Son originalité fondamentale réside dans la proposition d'un modèle prédictif du développement de l'infestation qui consiste à coupler un modèle thermique du silo avec un modèle biologique décrivant la croissance des insectes. Il est ainsi possible, avec l'appui de données complémentaires météorologiques, d'anticiper le développement des insectes et de lancer des alarmes préventives. Cette solution est accompagnée de développements électroniques et informatiques plus spécifiques de la surveillance continue des silos : un système de détection à l'entrée des silos ; une surveillance sur la partie haute du tas de grain la plus chaude ; une surveillance du tas de grains dans toute sa hauteur. Ces développements mettent en œuvre des modes de détections multiples (température, humidité, sonde acoustique, CO2). Toutes ces contributions techniques sont intégrées sous la forme d'un système complet de surveillance équipé d'une interface utilisateurs qui répond aux exigences du projet global ECOSILO. Les vérifications fonctionnelles ont été réalisées en laboratoire et sur site réel. Nous concluons sur les perspectives ouvertes par ce travail. / This thesis deals with new monitoring technologies applied to grain storage in silos. Since the first sedentary groups, cereals have been accounted as the main food for humans, as well as for livestock. The crops are seasonal and storage is a vital necessity for the world population, which currently has 7.2 billion inhabitants and will reach 9 billion in 2050. In this problematic around monitoring of silos, insects represent the first grain postharvest pest, causing considerable losses in some cases up to 10% of the production. Several techniques and methods have been developed and implemented in order to face the danger of these pests. The most common method is the use of synthetic chemical insecticides, which have an obvious negative effect on both, human health and the environment. This work is part of a cooperative program named ECOSILO, whose main objective is to design and create prototype ecological alternatives to the systematic and massive use of insecticides. This is therefore a largely multidisciplinary approach, in which we were in charge to conceptualize a comprehensive monitoring system to detect infestations early and automatically control of the attractive and insecticides spreading. Our proposal is based on logic of IPM and focuses on the prevention and early detection of possible infestations, in order to preserve stocks and to avoid reaching high level of economic loss. Its fundamental originality lies in the proposition of a predictive model of the development of the infestation, which consists of coupling a thermal model of the silo with a biological model describing insect growth. Thus, it is possible, with additional weather data support, to anticipate the development of insects and initiate preventive alarms. This solution is accompanied by more specific electronic and computer monitoring developments in silos: a detection system at the entrance of silos; a supervision of the top of the heap of grain which is the hottest; Monitoring of the heap of grain in its entire height. These developments are implementing multiple detection modes (temperature, humidity, acoustic probe, CO2). All these technical contributions are incorporated in the form of a comprehensive monitoring system with a user interface that meets the requirements of the overall project ECOSILO. The functional checks have been performed in laboratory and actual site. We conclude on the perspectives opened by this work.
30

Periodic Performance Analysis to Predict Student Success Rates

Senol, Nurettin Selcuk 20 May 2020 (has links)
No description available.

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