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1
Bruce, Julie. "Measurement and monitoring of surgical adverse events." Thesis, University of Aberdeen, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408939.
Повний текст джерелаАнотація:
The aim of this thesis is to investigate the validity of the measurement and the monitoring of surgical adverse events. Objectives: 1. To select surgical adverse events for detailed evaluation; 2. To investigate events with different epidemiological characteristics and attributes to assess the validity of their measurement and monitoring. Three events were selected: surgical wound infection, anastomotic leak and chronic post-surgical pain. Methods: Four systematic reviews and two epidemiological studies were conducted to investigate surgical wound infection, anastomotic leak and chronic post-surgical pain. A total of 41 definitions of wound infection were identified in the surgical literature, with little evidence of formal theoretical assessment of validity and reliability. Modified versions of Centres for Disease Control (CDC) definitions are currently used by UK nosocomial surveillance systems, although the impact of these modifications has not been evaluated. A total of 56 definitions for anastomotic leak were found. Although a national surgical consensus group proposed a definition for anastomotic leak, no evidence of its use was found in the surgical literature. The cohort study of 435 patients undergoing gastrointestinal surgery found that patients with anastomotic leak had poorer long-term survival at four years postoperatively, although patient numbers were small. The systematic review of chronic pain after cardiac study identified six prevalence studies worldwide, none of which used ‘standard’ definitions proposed by the International Association of the Study of Pain (IASP). A total of 1080 patients undergoing cardiac surgery at one regional cardiothoracic centre were assessed at two years postoperatively; the cumulative prevalence of chronic pain was 39% using a definition based on timing, location and pain characteristics.
2
Panzardi, Enza. "Measurement systems for industrial plants condition monitoring." Doctoral thesis, Università di Siena, 2019. http://hdl.handle.net/11365/1072401.
Повний текст джерелаАнотація:
Negli ultimi decenni, il mercato mondiale dell’energia ha dovuto far fronte ad una richiesta di produzione sempre crescente e ad un costante mutamento del settore industriale, sempre più attento all’impatto ambientale e all’innovazione tecnologica.
Oltre agli impianti per la produzione di energia da fonti rinnovabili, quelli a ciclo combinato o a cogenerazione basati su turbine a gas sono i più diffusi, in quanto garantiscono maggiore rendimento e minori emissioni, a parità di energia prodotta rispetto agli altri impianti a combustione disponibili nel settore. Inoltre, offrono una maggiore flessibilità operativa consentendo una migliore modulabilità del carico.
In questo contesto, una sempre maggiore spinta innovativa ha coinvolto gli operatori del settore nel mettere a punto nuove tecnologie di controllo e monitoraggio degli impianti per garantire una maggiore affidabilità e rimanere competitivi a lungo termine.
A tale scopo, sono diverse le tecniche che possono essere implementate per raccogliere informazioni sulle condizioni operative delle macchine, consentendo quindi un rilevamento e una manutenzione precoce dei guasti che posso avere un forte impatto sulla produttività e sulla riduzione complessiva dei costi.
Il mio lavoro di tesi si inserisce in questo contesto applicativo. L’obiettivo finale è stato quello di sviluppare delle tecniche di monitoraggio innovative e a basso costo basate sul principio di induzione elettrostatica per il rilevamento di detriti solidi, generati da guasti o malfunzionamenti, nel percorso dei gas di scarico di una turbomacchina.
In questo lavoro vengono presentati diversi sistemi innovativi di monitoraggio basati sull’utilizzo di sensori elettrostatici e amplificatori di carica, con prestazioni migliorate che possono essere impiegati anche in altre applicazioni che coinvolgono processi di combustione o in impianti industriali che impiegano tubazioni per il trasporto pneumatico.
Il sistema di rilevamento consiste in uno o più sensori elettrostatici montati all’interno del condotto di scarico della turbomacchina i quali rilevano le particelle con carica elettrostatica presenti nel flusso di gas. L’amplificatore di carica ha il compito di convertire il segnale di carica in un segnale di tensione adatto ad essere acquisito e processato da un sistema appositamente implementato.
La tecnica di misura implementata sfrutta le informazioni fornite dal modello fisico usato per descrivere il problema di misura e le caratteristiche geometriche del set-up scelto per i sensori per ricostruire la traiettoria, il livello di carica, la posizione e la velocità della particella carica rilevata.
Il sistema di misura realizzato è stato caratterizzato in un ampio intervallo di condizioni operative e studiato sia dal punto di vista teorico che sperimentale. In particolare, è stato sviluppato un sistema di misura basato su array circolari di tre sensori elettrostatici per il quale si riesce ad ottenere un errore relativo inferiore all’1% sulla stima dei parametri necessari alla ricostruzione della traiettoria, della velocità e della carica della particella in movimento rilevata.
Inoltre, dalla caratterizzazione teorica dell’accuratezza di misura del sistema emerge come quest’ultima sia indipendente dalla direzione assunta dalla particella in movimento rispetto alla disposizione dei sensori, garantendo un’accuratezza isotropica planare.
Inoltre, rimanendo nello stesso ambito applicativo, una parte di questo lavoro ha riguardato lo studio e la realizzazione di una sonda capacitiva triassiale. La particolarità del dispositivo proposto è quella di essere realizzato per essere depositato direttamente sul componente dell’impianto da monitorare e per questo definita: "on-component.
Un prototipo del sensore è stato realizzato con tecnologia serigrafica e il suo comportamento caratterizzato in frequenza, dimostrando caratteristiche comparabili alle comuni sonde triassiali ("bulk").
3
Monserrat, Hernández Oriol. "Deformation measurement and monitoring with Ground-Based SAR." Doctoral thesis, Universitat Politècnica de Catalunya, 2012. http://hdl.handle.net/10803/81557.
Повний текст джерелаАнотація:
The Ground-Based Synthetic Aperture Radar (GB-SAR) is a relatively new technique,
which in the last ten years has gained interest as deformation measurement and
monitoring tool. The GB-SAR technique is based on an imaging radar-based sensor, which
o ers high sensitivity to small displacements, in the region of sub-millimetres to
millimetres, long-range measurements, which can work up to some kilometres, and massive
deformation measurement capability. These features confer to the GB-SAR technique
interesting advantages with respect to other point-wise deformation measurement
techniques.
The process of estimating deformation from the GB-SAR data is not straightforward:
it requires complex data processing and analysis tools. This dissertation is focused on
these tools, covering the whole deformation estimation process. This thesis collects the
main research results achieved on this topic during my work at the Active Remote Sensing
Unit of the Institute of Geomatics. Two di erent approaches for measuring deformation
with GB-SAR data are described and discussed. The irst one is the interferometric
approach, based on the exploitation of the phase component of the GB-SAR data, which
is the commonly used GB-SAR method. The second one is a non-interferometric approach,
which exploits the amplitude component of the GB-SAR data, o ering an interesting
alternative way to exploit the GB-SAR data.
This dissertation has two main objectives. The first one is presenting, step by step, a
complete interferometric GB-SAR procedure for deformation measuring and monitoring.
The second one is presenting two new algorithms, which represent the most innovative
part of this thesis. The first algorithm faces the phase unwrapping problem, providing an
automatic solution for detecting and correcting unwrapping errors, which is called 2+1D
phase unwrapping. The second algorithm is the base of the above mentioned non-
interferometric approach, which overcomes some of the most critical limitation of GB-SAR
interferometry, at the expense of getting less precise deformation estimates.
The dissertation is divided in 6 chapters. The first one is the introduction, while the
second one provides an overview of GB-SAR interferometry, introducing the main aspects
that are the basics of the subsequent chapters. Chapter 3 describes a complete GB-SAR
processing chain. Chapters 4 and 5 contain the most original part of the dissertation, i.e.
the 2D+1 phase unwrapping algorithm, and the non-interferometric approach. Finally, in
Chapter 6 the conclusions are discussed and further research is proposed.El radar terrestre d’obertura sintètica (GB-SAR) és una tècnica relativament nova que, en els últims deu anys, ha guanyat interès com a eina per a mesurar i monitorar deformacions. La tècnica GB-SAR es basa en un sistema radar amb capacitat per proporcionar imatges, que ofereix una alta sensibilitat a petits desplaçaments, d’ordre mil·limètric o submil·limètric, que és capaç de mesurar a llargues distàncies (alguns km) i que té una alta capacitat per fer mesures massives. Aquestes característiques donen a la tècnica interessants avantatges respecte a altres tècniques clàssiques de mesura de deformacions, típicament basades en mesures puntuals. Derivar mesures de deformació a partir de dades GB-SAR no és un procés senzill, ja que requereix uns procediments complexos de processat i anàlisi de dades. Aquesta tesi es centra en aquests processos. Aquesta tesi recull alguns dels resultats més destacats de la investigació que he desenvolupat sobre aquest tema a la unitat de Teledetecció Activa de l'Institut de Geomàtica. Al llarg del document es descriuen dues aproximacions diferents per mesurar deformacions amb GB-SAR. Una es basa en la explotació de la tècnica de la interferometria, és a dir explotant la component de la fase de les imatges GB-SAR: és la tècnica GB-SAR usada habitualment. La segona, anomenada tècnica no-interferomètrica, es basa en la component de l’amplitud de les dades GB-SAR i ofereix una interessant alternativa a la primera. La tesi acompleix dos objectius principals. En primer lloc presenta un procediment complet per la mesura i monitoratge de deformacions mitjançant interferometria GB-SAR. En segon lloc, descriu dos nous algorismes que resolen problemes específics de la interferometria clàssica aplicada al GB-SAR i que representen la part més innovadora d’aquesta tesi. El primer algorisme aborda un dels problemes oberts de la interferometria, el phase unwrapping, proposant un mètode automàtic per detectar-ne i corregir-ne els errors. El segon algorisme proposa un nou mètode per a l'explotació de les dades GB-SAR per mesurar deformacions sense utilitzar la interferometria. La estructura de la tesi consisteix en sis capítols. Després de la introducció, el Capítol 2 proporciona una visió general de la interferometria GB-SAR, introduint els conceptes principals utilitzats en la tesi. En el tercer capítol es descriu una cadena de processament basada en GB-SAR interferomètric. Els capítols quart i cinquè contenen la part més original de la tesi: l'algorisme de phase unwrapping i el mètode no-interferomètric per la mesura de deformacions. Finalment, es discuteixen les conclusions principals i es proposen futures línies d’investigació.
4
Guo, Dongsheng. "Power transformer condition monitoring with partial discharge measurement." Thesis, Glasgow Caledonian University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443183.
Повний текст джерела
5
Tri, Rachmanto. "Monitoring of biodiesel transesterification process using impedance measurement." Thesis, Liverpool John Moores University, 2014. http://researchonline.ljmu.ac.uk/4337/.
Повний текст джерелаАнотація:
Alternative diesel fuels have been the subject of extensive investigation. Fatty acid methyl ester (FAME) based Biodiesel manufactured from vegetable oils or animal fats is an excellent candidate to replace common diesel fuel being renewable, non-toxic and often giving rise to reduced exhaust gas emissions. The transesterification process has been commonly and widely used to produce biodiesel from vegetable oil or animal fat. Vegetable oils or animal fats generally have viscosities higher than standard diesel oil. This means that it is necessary to reduce the viscosity by means of reacting vegetable oil with alcohol in the presence of a suitable catalyst. The target product for this reaction is methyl ester, with glycerol and potentially soap produced as by products with the process of transesterification. Methylester (Biodiesel) is produced by converting triglycerides to alkylesters. A batch transesterification process has two significant mechanisms, and exhibits a mass transfer controlled region that precedes a second order kinetically controlled region. In order to control the conversion process it is useful to employ process monitoring. In particular monitoring of the mass transfer processes that limits the initial reaction rates could prove to be beneficial in allowing for process optimization and control. This thesis proposes the use of a new method of biodiesel process monitoring using low frequency (15kHz) impedance sensing which is able to provide information regarding the progress of mass transfer and chemical reaction during biodiesel production. An interdigitated (ID) sensor has been used to monitoring the biodiesel process The ID sensor is of simple construction and consists of two sets of interleaved electrodes (fingers). The two sets of electrodes are separated by a gap and when an AC excitation voltage is applied across the interleaved electrodes an oscillating electric field is developed. The response of the fluid surrounding the sensor to the applied excitation was then used to determine progress of the chemical reaction by evaluating the real and complex impedance. A significant and unambiguous change in the components of impedance has been shown to occur during mixing (mass transfer) and transesterification. The impedance measurements gained during transesterification were then used for the development of a system model. A systematic approach was used to select mathematical models and system identification techniques were evaluated. The system identification investigation used real process measurement data in conjunction with the Matlab system identification toolbox.
6
Cherednichenko, O. Yu, Yu Gontar, and A. Matveyev. "Towards monitoring and evaluation information system development." Thesis, NTU "KhPI", 2017. http://repository.kpi.kharkov.ua/handle/KhPI-Press/38250.
Повний текст джерела
7
Kumar, Abhishek. "Network Data Streaming: Algorithms for Network Measurement and Monitoring." Diss., Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-11172005-143837/.
Повний текст джерелаАнотація:
Thesis (Ph. D.)--Computing, Georgia Institute of Technology, 2006.Dr. Mostafa Ammar, Committee Member ; Dr. Mark Crovella, Committee Member ; Dr. Constantinos Dovrolis, Committee Member ; Dr. Ellen Zegura, Committee Chair ; Dr. Jun Xu, Committee Chair. Vita. Includes bibliographical references.
8
Araujo, Cespedes Fabiola. "Respiratory Monitoring System Based on the Thoracic Expansion Measurement." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/3953.
Повний текст джерелаАнотація:
The purpose of this reasearch was to develop a respiratory monitoring system using a reflective object sensor based belt to measure the thoracic expansion of a neonatal for future application at the medical center of the Universidad Evangelica Boliviana (UEB). This medical center, being founded by the UEB University, is dedicated to help and serve the poor and currently has no respiratory monitoring system.
The methodology used was first to build and test the respiratory sensor belt and test the relationship between the blet expansion and the voltage generated. The, to incorporate the respiratory sensor belt in a system that would allow individual testing as well as group testing in a wireless network. The system was simulated using an expandable plastic container that was expanded and extracted periodically, registering the results in a MATLAB software.
The system gave successful results and generated the frequency results of each cycle, average frequency and deviation frequency. The system demonstrated to be reliable and to have repeatable results.
9
Begg, David William. "Advanced strain measurement techniques for monitoring full scale structures." Thesis, University of Portsmouth, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316720.
Повний текст джерела
10
Bisht, Saurabh Singh. "Vibration Measurement Based Damage Identification for Structural Health Monitoring." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/77301.
Повний текст джерелаАнотація:
The focus of this research is on the development of vibration response-based damage detection in civil engineering structures. Modal parameter-based and model identification-based approaches have been considered. In the modal parameter-based approach, the flexibility and curvature flexibility matrices of the structure are used to identify the damage. It is shown that changes in these matrices can be related to changes in stiffness values of individual structural members. Using this relationship, a method is proposed to solve for the change in stiffness values. The application of this approach is demonstrated on the benchmark problem developed by the joint International Association of Structural Control and American Society of Civil Engineers Structural Health Monitoring task group. The proposed approach is found to be effective in identifying various damage scenarios of this benchmark problem. The effect of missing modes on the damage identification scheme is also studied.
The second method for damage identification aims at identifying sudden changes in stiffness for real time applications. It is shown that the high-frequency content of the response acceleration can be used to identify the instant at which a structure suffers a sudden reduction in its stiffness value. Using the Gibb's phenomenon, it is shown why a high-pass filter can be used for identifying such damages. The application of high-pass filters is then shown in identifying sudden stiffness changes in a linear multi-degree-of-freedom system and a bilinear single degree of freedom system. The impact of measurement noise on the identification approach is also studied. The noise characteristics under which damage identification can or cannot be made are clearly identified. The issue of quantification of the stiffness reduction by this approach is also examined. It is noted that even if the time at which the reduction in stiffness happens can be identified, the quantification of damage requires the knowledge of system displacement values. In principle, such displacements can be calculated by numerical integration of the acceleration response, but the numerical integrations are known to suffer from the low frequency drift error problems. To avoid the errors introduced due to numerical integration of the acceleration response, an approach utilizing the unscented Kalman filter is developed to track the sudden changes in stiffness values. This approach is referred to as the adaptive unscented Kalman filter (AUKF) approach. The successful application of the proposed AUKF approach is shown on two multi-degree of freedom systems that experience sudden loss of stiffness values while subjected to earthquake induced base excitation.Ph. D.
11
Zeng, Zheng. "Remote Data Monitoring to the Cloud for Apiary Measurement." Thesis, Zeng, Zheng (2017) Remote Data Monitoring to the Cloud for Apiary Measurement. Honours thesis, Murdoch University, 2017. https://researchrepository.murdoch.edu.au/id/eprint/40012/.
Повний текст джерелаАнотація:
Apiary industry manages bees and makes the product from this insect. There are about 10,000 registered beekeepers in Australia that operate 600,000 hives. However, these beekeepers are mostly take various measurements from beehives manually. This provides significant workloads of the beekeepers as well as the maintenance fee. Since the rapid development of IoT (Internet of Things) technology, it is possible to take measurements remotely via the IoT microcontrollers. An owner of a bee farm approached the author via their contractor, for designing a low-cost solution for a remote monitoring system that allows the various apiary measurements. The design allows different parameters to be monitored automatically without human force, including the hive weight, the temperature, the level of rainfall, and the water level of the tank for hydrating bees. This thesis contained the design procedure for the remote apiary data monitoring system, investigating various sensors, development of the system’s software, laboratories for verifying various theories/assumptions; calculations for the system’s power consumption, etc. The simulation results for this system is demonstrated in this paper; the results indicate that the system is available to monitor data via the cloud, generating reports and sending the notification message to the end user by SMS/Email. Therefore, it can reduce the workload by preventing the beekeeper from frequently coming to the Beehive.
12
Hazuka, John Anthony 1964. "Evaluation of chemcassette technology for monitoring low-levels of nitrogen-dioxide." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276766.
Повний текст джерелаАнотація:
Problems associated with instruments used to measure low levels of NO₂ include non-specificity, low sensitivity, and an uncharacterized dependence on environmental conditions. MDA Scientific has recently introduced a continuous colorimetric tape technique (chemcassette) to monitor for pollutant gases. Advantages of this technology include ease of use, fast-response alarm capability, and adaptability to measure different pollutants. This research characterized and compared chemcassette performance for NO₂ with other low-level NO₂ monitoring technologies including the luminox LMA-3 monitor and the EPA reference CSI chemiluminescnt monitor. The test protocol was based on EPA procedures. The chemcassette was found to be sensitive to temperature and relative humidity effects. The chemiluminescent monitor had the best overall performance. The luminox monitor displayed temperature dependence. Variation in stability of the chemcassette optical system, tape paper uniformity, and possible interference from ozone were characterized. (Abstract shortened with permission of author.)
13
VAN, MILLIGEN FRED JOSEPH. "IN-SITU MONITORING OF THIN FILM GROWTH USING A WIDE-BAND SCANNING MONOCHROMATOR." Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/188057.
Повний текст джерелаАнотація:
To augment the monitoring capabilities of a Balzers 760 coating chamber, we replaced the simple, single wavelength optical monitor with a wide-band scanning monochromator system which records transmission data over the visible region of the spectrum. The system is controlled by an IBM-PC. The same computer is also interfaced to a quartz crystal monitoring system which was purchased with the Balzers chamber. The scanning monochromator system required a new brighter light source to deliver sufficient signal to the detector array through the more complex, dispersive optical train. Above the chamber the filter and the photomultiplier pair were removed, and replaced by a flat mirror which diverts the beam horizontally into the scanning monochromator system. The beam passes first through a telescope-slit configuration onto a Jobin-Yvon holographic grating, built to disperse the 400-800 nm band of which we use approximately 360 nm. This reflective grating images the spectrum of the slit onto a Fairchild CCD array, which consists of 1728 elements. These elements are then averaged into 173 data points and recorded by the IBM-PC. The 173 data points allows us a wavelength resolution of about 2 nm. The IBM incorporates a Tecmar A/D board in accepting data from both the quartz crystal monitor and the scanning monochromator system. Although the system is capable of recording data at a faster rate, it is generally stored once every three seconds. This is adequate since at normal deposition rates this gives us information every 10 - 20 Angstroms of deposited material. The system has been used in several applications which will be discussed in this dissertation. They include in situ measurements of water adsorption into a film, derivation of optical constant profiles during the film deposition, both of which may lead us to a better understanding of the growth of a thin film. The monochromator has also been used to analyze the components of a multilayer coating by monitoring the film's transmission spectra while it was sputter-etched off. The extension of the system into the ultraviolet region of the spectrum and some future applications are also considered.
14
Dourado, Raphael Augusto de Sousa. "Monitoring use cases in the FIBRE-BR testbed." Universidade Federal de Pernambuco, 2014. https://repositorio.ufpe.br/handle/123456789/11972.
Повний текст джерелаАнотація:
Many researchers believe that the Internet is “ossified”, that is, its design is preventing
the network to evolve in aspects such as security, mobility, and content distribution. However,
it is difficult to test new ideas in a production environment like the Internet due to its stability
requirements. As an alternative, part of the network research community is focused on building
large-scale infrastructures called testbeds, where they can build their “own” network and test
their ideas in a more realistic environment, similar to the Internet itself. This work discusses the
challenges of a key function in a testbed: monitoring. To do this, we reviewed the state-of-the-art
in monitoring systems for testbeds and then identified, described, and implemented a set of
monitoring use cases in the FIBRE testbed. By implementing these use cases, we validate our
proposals and lay a framework reusable in other similar environments.Submitted by Luiz Felipe Barbosa (luiz.fbabreu2@ufpe.br) on 2015-03-10T17:26:38Z No. of bitstreams: 2 DISSERTAÇÃO Raphael Augusto de Sousa Dourado.pdf: 6341527 bytes, checksum: c6ee052e4d2ce1085459d2bca175af0e (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5)
Made available in DSpace on 2015-03-11T17:36:24Z (GMT). No. of bitstreams: 2 DISSERTAÇÃO Raphael Augusto de Sousa Dourado.pdf: 6341527 bytes, checksum: c6ee052e4d2ce1085459d2bca175af0e (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2014-07-24
Muitos pesquisadores acreditam que a Internet está “ossificada”, ou seja, sua própria estrutura a impede de evoluir em aspectos como segurança, mobilidade e distribuição de conteúdo. No entanto, há uma dificuldade em testar novas ideias em ambiente de produção como a Internet devido aos requisitos de estabilidade dos mesmos. Este impasse levou parte da comunidade de pesquisa em Redes de Computadores a construir infraestruturas em larga escala chamadas testbeds, onde pesquisadores podem montar sua “própria” rede privada e então testar suas ideias em um ambiente similar à Internet. Este trabalho discute os desafios de uma das principais tarefas de um testbed: monitoração. Para tal, foi realizado um levantamento do estado da arte em sistemas de monitoração para testbeds e, a partir deste estudo, foi identificado, descrito e implementado um conjunto de casos de uso de monitoração no contexto do testbed FIBRE. A implementação destes casos de uso validou as propostas deste trabalho, as quais podem também ser aplicadas a outros ambientes similares.
15
Jazayeri, Sina. "Measurement and monitoring of moisture content in timber and investigations of moisture gradients using dielectric measurements." Thesis, University of Bedfordshire, 1999. http://hdl.handle.net/10547/622156.
Повний текст джерелаАнотація:
This thesis addresses various issues in connection with the measurement of moisture content in timber. The early parts include long term experimentally based studies which culminated in producing recommendations to existing British Standards for equilibrium moisture content (EMC) of timber in internal environments. Findings consistently showed lower EMCs than existing recommended values; these are believed to be caused by socio-economic factors. Intermediate sections of the thesis continue with tests on electrical methods of moisture content measurement to establish a basis for comparability and the claimed accuracy of currently available moisture meters in the market. To this end, the performance of a wide range of resistance-type moisture meters in worldwide use was critically investigated under laboratory conditions - it was established that even under the strict controlled conditions of the study, large discrepancies are not uncommon (as great as 13% moisture content difference was observed). While some instruments consistently underestimated, others overestimated under identical conditions. Lack of agreed standards for species corrections and temperature correction factors were found to be the main cause of disagreement between the meters. Further discussions include the layout for a proposed standard in which agreed values for species and temperature correction factors would be established. In the latter part of the thesis moisture gradients in timber, the causes and the current methods of assessment are discussed. In particular, the performance of a leading brand capacitance-type moisture meter was systematically investigated both in the absence and in the presence of predetermined moisture gradients. It was established that moisture gradients severely affect the measured moisture content. A computer controlled capacitance measurement system based on resonance detection was developed to initially replicate the behaviour of conventional capacitance-type moisture meters, and to further investigate possible moisture gradient detection protocols. Two electrode designs were used in order to investigate methods by which moisture gradients could be detected. It was shown that a multi-plate electrode can be used to detect moisture gradients in timber to depths of at least 10 mm.
16
Romanova, Anna. "Acoustic monitoring of hydraulic resistance in partially full pipes." Thesis, University of Bradford, 2013. http://hdl.handle.net/10454/6321.
Повний текст джерелаАнотація:
Hydraulic losses in sewer pipes are caused by wall roughness, blockages and in-pipe sedimentation. Hydraulic resistance is a key parameter that is used to account for the hydraulic energy losses and predict the sewer system propensity to flood. Unfortunately, there are no objective methods to measure the hydraulic resistance in live sewers. A common method to estimate the hydraulic resistance of a sewer is to analyse collected CCTV images and then to compare them against a number of suggested hydraulic roughness values published in the Sewer Rehabilitation Manual. This thesis reports on the development of a novel, non-invasive acoustic method and instrumentation to measure the hydraulic roughness in partially filled pipes under various structural and operational conditions objectively. This research presents systematic laboratory and field studies of the hydraulic and surface water wave characteristics, of shallow water flows in a sewer pipes with the presence of local and distributed roughness, in order to relate them to some fundamental properties of the acoustic field measured in the vicinity of the flow surface. The results of this thesis indicate that for the local roughness the energy content of the reflected acoustic signal is an indicator of the pipe head loss and hydraulic roughness. In the case of the distributed roughness, the variation in the temporal and frequency characteristics of the propagated sound wave can be related empirically to the mean flow depth, mean velocity, wave standard deviation and hydraulic roughness.
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Berglöf, Carl. "On measurement and monitoring of reactivity in subcritical reactor systems." Doctoral thesis, KTH, Reaktorfysik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-12483.
Повний текст джерелаАнотація:
Accelerator-driven systems have been proposed for incineration of transuranic elements from spent nuclear fuel. For safe operation of such facilities, a robust method for reactivity monitoring is required. Experience has shown that the performance of reactivity measurement methods in terms of accuracy and applicability is highly system dependent. Further investigations are needed to increase the knowledge data bank before applying the methods to an industrial facility and to achieve license to operate such a facility. In this thesis, two systems have been subject to investigation of various reactivity measurement methods. Conditions for successful utilization of the methods are presented, based on the experimental experience. In contrast to previous studies in this field, the reactivity has not only been determined, but also monitored based on the so called beam trip methodology which is applicable also to non-zero power systems. The results of this work constitute a part of the knowledge base for the definition of a validated online reactivity monitoring methodology for facilities currently being under development in Europe (XT-ADS and EFIT).QC 20100621
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Jaafar, Mohd Zaidi. "Measurement of Streaming Potential for Oilfield Monitoring in Intelligent Wells." Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.516468.
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Rennie, Kirsten Louise. "Heart rate monitoring as a measurement instrument in epidemiological studies." Thesis, University of Cambridge, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621802.
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Johnstone, James Alexander. "The measurement of sporting performance using mobile physiological monitoring technology." Thesis, University of Hertfordshire, 2014. http://hdl.handle.net/2299/13527.
Повний текст джерелаАнотація:
Coaches are constantly seeking more ecologically valid and reliable data to improve professional sporting performance. Using unobtrusive, valid and reliable mobile physiological monitoring devices may assist in achieving this aim. For example, there is limited information regarding professional fast bowlers in cricket and understanding this role during competitive in-match scenarios rather than in simulated bowling events could enhance coaching and physical conditioning practices. The BioharnessTM is a mobile monitoring device and assesses 5 variables (Heart rate [HR], Breathing frequency [BF], Accelerometry [ACC], Skin temperature [ST] and Posture [P]) simultaneously. Therefore, the aims of this research were to assess the effectiveness of the BioharnessTM mobile monitoring device during professional sporting performance using fast bowlers in cricket and this was to be achieved in five research studies. Study 1 presented the physiological profile of professional cricketers reporting fitness data with other comparable professional athletes, with a specific interest in fast bowlers who were to be the focus of this work. The 2nd and 3rd study assessed the reliability and validity of the BioharnessTM through controlled laboratory based assessment. For validity, strong relationships (r = .89 to .99, P < .01) were reported for HR, BF, ACC and P. Limits of Agreement reported HR (-3 ± 32 beat.min-1), BF (-3.5 ± 43.7 br.min-1) and P (0.2 ± 2.6o). ST established moderate relationships (-0.61 ± 1.98 oC; r =.76, P <.01). Reliability between subject data reported low Coefficient of Variation (CV) and strong correlations for ACC and P (CV < 7.6%; r = .99, P <.01). HR and BF (CV ~ 19.4%; r ~.70, P <.01) and ST (CV 3.7%; r = .61, P < .01), present more variable data. Intra and inter device data presented strong relationships (r > .89, P < .01, CV < 10.1%) for HR, ACC, P and ST. BF produced weaker data (r < .72, CV < 17.4%). Study 4 assessed reliability and validity of the BioharnessTM in a field based environment using an intermittent protocol. Precision of measurement reported good relationships (r = .61 to .67, P < .01) and large Limits of Agreement for HR (> 79.2 beat.min-1) and BF (> 54.7 br.min-1). ACC presented excellent precision (r = .94, P < .01). Results for HR (r = ~ .91, P < .01: CV <7.6%) and ACC (r > .97, P < .01; CV < 14.7%) suggested these variables are reliable in the field environment. BF presented more variable data (r = .46 - .61, P < .01; CV < 23.7%). In all studies, as velocity of movement increased (> 10 km.h-1) variables became more erroneous. HR and ACC were deemed as valid and reliable to be assessed during in-match sporting performance in study 5. This final study sought to utilise and assess the BioharnessTM device within professional cricket, assessing physiological responses of fast-medium bowlers within a competitive sporting environment, collected over three summer seasons. The BioharnessTM presented different physiological profiles for One Day (OD) and Multi Day (MD) cricket with higher mean HR (142 vs 137 beats.min-1, P < .05) and ACC (Peak acceleration (PkA) 227.6 vs 214.9 ct.episode-1, P < .01) values in the shorter match format. Differences in data for the varying match states of bowling (HR, 142 vs 137 beats.min-1, PkA 234.1 vs 226.6 ct.episode-1), between over (HR, 129 vs 120beats.min-1, PkA 136.4 vs 126.5 ct.episode-1) and fielding (115 vs 106 beats.min-1, PkA 1349.9 vs 356.1 ct.episode-1) were reported across OD and MD cricket. Therefore, this information suggests to the coach that the training regimes for fast bowlers should be specific for the different demands specific to the format of the game employed. Relationships between in-match BioharnessTM data and bowling performance were not clearly established due to the complexities of uncontrollable variables within competitive cricket. In conclusion, the BioharnessTM has demonstrated acceptable validity and reliability in the laboratory and the field setting for all variables (Heart rate, Breathing frequency, Accelerometry, Skin temperature and Posture) but with limitations for heart rate and breathing frequency at the more extreme levels of performance. Furthermore, taking these limitations into account it has successfully been utilised to assess performance and provide further insight into the physiological demands in the professional sport setting. Therefore, this work suggests that coaches and exercise scientists working together should seek to utilise new mobile monitoring technology to access unique insights in to sporting performance which may be unobtainable in the laboratory or a simulated field based event.
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Elbadawy, Mohamed Mohamed Zeinelabdin Mohamed. "Dynamic Strain Measurement Based Damage Identification for Structural Health Monitoring." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/86167.
Повний текст джерелаАнотація:
Structural Health Monitoring (SHM) is a non-destructive evaluation tool that assesses the functionality of structural systems that are used in the civil, mechanical and aerospace engineering practices. A much desirable objective of a SHM system is to provide a continuous monitoring service at a minimal cost with ability to identify problems even in inaccessible structural components. In this dissertation, several such approaches that utilize the measured dynamic response of structural systems are presented to detect, locate, and quantify the damages that are likely to occur in structures. In this study, the structural damage is identified as a reduction in the stiffness characteristics of the structural elements. The primary focus of this study is on the utilization of measured dynamic strains for damage identification in the framed structures which are composed of interconnected beam elements. Although linear accelerations, being more convenient to measure, are commonly used in most SHM practices, herein the strains being more sensitive to elemental damage are considered. Two different approaches are investigated and proposed to identify the structural element stiffness properties. Both approaches are mode-based, requiring first the identification of system modes from the measured strain responses followed by the identification of the element stiffness coefficients. The first approach utilizes the Eigen equation of the finite element model of the structure, while the second approach utilizes the changes caused by the damage in the structural curvature flexibilities. To reduce size of the system which is primarily determined by the number of sensors deployed for the dynamic data collection, measurement sensitivity-based sensor selection criterion is observed to be effective and thus used. The mean square values of the measurements with respect to the stiffness coefficients of the structural elements are used as the effective measures of the measurement sensitivities at different sensor locations. Numerical simulations are used to evaluate the proposed identification approaches as well as to validate the sensitivity-based optimal sensor deployment approach.Ph. D.
All modern societies depend heavily on civil infrastructure systems such as transportation systems, power generation and transmission systems, and data communication systems for their day-to-day activities and survival. It has become extremely important that these systems are constantly watched and maintained to ensure their functionality. All these infrastructure systems utilize structural systems of different forms such as buildings, bridges, airplanes, data communication towers, etc. that carry the service and environmental loads that are imposed on them. These structural systems deteriorate over time because of natural material degradation. They can also get damaged due to excessive load demands and unknown construction deficiencies. It is necessary that condition of these structural systems is known at all times to maintain their functionality and to avoid sudden breakdowns and associated ensuing problems. This condition assessment of structural systems, now commonly known as structural health monitoring, is commonly done by visual onsite inspections manually performed at pre-decided time intervals such as on monthly and yearly basis. The length of this inspection time interval usually depends on the relative importance of the structure towards the functionality of the larger infrastructure system. This manual inspection can be highly time and resource consuming, and often ineffective in catching structural defects that are inaccessible and those that occur in between the scheduled inspection times and dates. However, the development of new sensors, new instrumentation techniques, and large data transfer and processing methods now make it possible to do this structural health monitoring on a continuous basis. The primary objective of this study is to utilize the measured dynamic or time varying strains on structural components such as beams, columns and other structural members to detect the location and level of a damage in one or more structural elements before they become serious. This detection can be done on a continuous basis by analyzing the available strain response data. This approach is expected to be especially helpful in alerting the owner of a structure by identifying the iv occurrence of a damage, if any, immediately after an unanticipated occurrence of a natural event such as a strong earthquake or a damaging wind storm.
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Palmer, Iain Alastair. "Condition monitoring and optical strain measurement for power industry components." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/9195.
Повний текст джерелаАнотація:
Condition monitoring and life extension of components is vital to reducing risk of failure and operational costs in the power industry. Optical strain measurement techniques have been studied and developed for use in condition monitoring of power plant steam pipes and wind turbine components. In addition, these techniques have been used to assist evaluation of damage mechanisms in these components. Power plant steam pipes operate at high temperature (approximately 600°C) and pressure, and as a result undergo large creep deformations. Monitoring creep strain is a key factor in assessing remaining life of important components. An optical strain measurement system developed by EON, Automatic Reference Creep Measurement And Control (ARCMAC) has been researched as to its combined effectiveness with Digital Image Correlation (DIC) in obtaining accurate and reliable strain measurement for high temperature components. DIC has also been used to monitor and evaluate damage in composite wind turbine blade components. The use of this optical strain technique has allowed comparison of experimentally-derived full-field strain maps to be compared with finite element analysis (FEA) results. Additionally, the use of acoustic emission (AE) as a condition monitoring technique for wind turbine blades has been investigated. Use of these techniques has given greater understanding of failure mechanisms in wind turbine components; in particular, transverse tensile damage and delamination have been investigated. The influence of the Brazier effect upon wind turbine blade failure has also been researched. Results of this research have evaluated accuracy of using optical strain measurement techniques as well as their ability to effectively measure strain in particular regions of interest. The application of such techniques is an important requirement for both power plant and wind turbine components. Finally, studies into the use of optical strain measurement techniques as lab-based tools to study failure mechanisms have been performed.
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Coenen, Lance Gregory 1959. "MULTI-STEP COULOSTATIC IMPULSE GENERATOR AND POTENTIAL MONITORING SYSTEM." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276529.
Повний текст джерелаАнотація:
A Coulostatic Impulse Generator (CIG) is an electronic device that transfers electrical charge to and from a pair of electrodes inserted in plant tissue. Six discrete charge transfers can be implemented in any desired sequence. The major purpose of the CIG is to determine the electrochemical constituents of the plant apoplast electrolyte. The objective of this thesis is threefold: (1) to design, construct and test the supervisory circuitry of the CIG, (2) to design, construct and test the interface between the NEC portable computer and the CIG, (3) to generate utility software to control each circuit board in the system. To handle the extreme difference in the timing of the charge transfer (microseconds) and the subsequent plant response a three step timing sequence is employed which permits an independent range of sample times and sample numbers. Data acquired is first stored in RAM in the computer within the CIG and then transferred to the external computer. (Abstract shortened with permission of author.)
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McHardy, Karina Mariya. "Obesity monitoring in schools." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:3934cc2c-efcb-4d10-a64c-aa4d657f6719.
Повний текст джерелаАнотація:
Background: Population level child measurement is an established international practice. However, there is limited clarity around the protocol and roles of school-based child measurement programmes (CMPs). Furthermore, questions remain about the positive and adverse outcomes associated with CMPs, as well as their longer-term sustainability. This research contributes new information by addressing these key unanswered questions. Methods: This thesis describes a three-part, mixed methods research project incorporating: a systematic literature review of existing CMPs; an in-depth case study of England’s National Child Measurement Programme; and the development, pilot implementation and evaluation of a CMP in Guernsey. This research was conducted sequentially; individual components informed and guided subsequent work. Results: Routine child measurement is a popular, complex and adaptive practice and offers significant epidemiological value. The principal roles of CMPs are delivery of local prevalence data and assessment of longitudinal trends. However, CMPs are often tasked with additional, diverse and changing roles that do not translate to acknowledged outcomes. Specifically, feedback of individual results represents an unproven programme element. Programme roles can evolve according to political, logistical, or other influences, without consideration of available evidence or wider-reaching implications. There is no evidence of short-term harm from CMPs. Evaluation of the pilot CMP in Guernsey demonstrated that these programmes are perceived to be feasible, acceptable and sustainable. Conclusions: To maximise the broader utility of CMPs, there should be clarity and consistency around their aims, roles and outcomes. Overall, surveillance reflects the preferred programme type. All CMPs should incorporate a standardised, rigorously applied protocol and routine evaluation. These features are essential to ensure the accuracy and comparability of resultant data, as well as programme credibility. Population level CMPs should not function in isolation; instead, they should be integrated into comprehensive strategies for obesity management. This research has important implications for CMP stakeholders and the wider public health arena.
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Al-Rawi, S. A. N. "Silicon sublimation at ultra high vacuum with microprocessor monitoring and measurements." Thesis, University of Kent, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382189.
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Hauser-Ehninger, Ulrich. "A measurement system for the monitoring and measurement of earthing grid performance at large high voltage substations." Thesis, Cardiff University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.527123.
Повний текст джерелаАнотація:
Earthing grids are a major part of high voltage plant at electrical installations ensuring good operation of equipment and the safety of personnel and the general public. Therefore, for improved safety, it is essential to keep the earthing grid impedance as low as possible at all times. A continuous on-line monitoring of the earthing grid is, therefore, desirable. This thesis presents the investigations and improvements to existing practice which were carried out to help the development of such a monitoring system. It also describes the specification, analysis, set up and performance tests of a prototype monitoring system. Extensive measurements in a laboratory environment, at the Cardiff University Outdoor Test Site, and at operating electrical substations and tower lines were used to validate the developed system. The literature review carried out in this work concentrated on measurement techniques used in earthing systems and safety issues related to electrical substations and tower lines. The accuracy of the existing impedance measurement system, IMS, developed at Cardiff, was examined, and the errors involved were quantified for the first time. The investigation was then concentrated on developing a fully computerised earth impedance measurement system, CEIMS, which not only allows more accurate evaluation of the test-electrode parameters but also permits savings on expensive lock-in amplifiers. The developed new algorithms allow frequency discrimination using advanced digital signal processing techniques. The extensive experimental work carried out within this programme, in the laboratory, at the Cardiff University Outdoor Test Site, and at operating substations and tower lines, has led to improvements in field test set-ups and better isolation techniques. More importantly, two new methods were developed; one is for the measurement of earth electrode resistance using the power consumption principle, while the other is for monitoring the earthing impedance of large substations. The latter technique does not require any auxiliary current injection but takes advantage of earth-wire currents flowing into/out of the substation earth grid. It is shown that if a large proportion of these currents is measured, changes to the earth grid impedance can be assessedc ontinuously.
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Jones, Erle Baxter 1953. "Short-term variation during asbestos abatement activities." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276531.
Повний текст джерелаАнотація:
The fibrous aerosol monitor (FAM) was designed to count fibrous particulates as accurately as the standard method, P & CAM 239, now NIOSH 7400. The Hi-Vol (HV) method, a modification of the standard method, was developed to collect fibers over a shorter time interval (i.e., 10-minutes) with the same accuracy as the standard method. The current study sought to compare the HV method with the FAM to assess its validity in measuring airborne asbestos levels and to assess the importance of short-term variation in asbestos levels in determining appropriate respiratory protection. Correlation between the FAM and HV showed a poor linear relationship in all comparison studies. However, there was good correlation between the average of short-term HV samples and long-term time-weighted average (TWA) samples at reported low levels of airborne asbestos. All membrane filter techniques showed strong correlation with each other, but were weakly correlated with the FAM. (Abstract shortened with permission of author.)
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Pérez-Vázquez, Losada Sonia. "Implementation of and Electrical Bioimpedance Measurement System for Renal Function Monitoring." Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-18839.
Повний текст джерелаАнотація:
Peritoneal Dialysis is a treatment for patients suffering from renal failure thatallows out-patient care. This means that the patient only needs to visit the hospital forconsultation and not for treatment, increasing considerably the comfort of the patient,while reducing remarkably the cost per patient.In order to increase the level of medical supervision obtained with the periodicvisits to the clinic, televisit has been put into practice in some hospitals. But thesetelevisits are based on indirect and qualitative indicators of renal failure, and thereforethey are just valid for detection of situations near limit cases, such as well over-hydratedor dehydrated.Electrical Bioimpedance Measurements have been proved to constitute anappropriate method for assessment of body composition, and therefore they can providewith direct indicators of body fluid distribution. Such ability of EBI technology allowsthe detection of body fluid unbalance caused by renal dysfunction, and therefore,nephrology televisits would benefit tremendously from EBI measurements.This project is based on the AD5933 Impedance Network Analyzer of AnalogDevices, and the main task is to develop a software application that controls theevaluation board in which it is implemented, and allows the storage of the EBImeasurements in EDF+ files that will facilitate the management of medical data whenapplied to televisit. These files are uploaded to XML format in order to be sent to aremote server, where a software application will have been implemented for medicalconsultation.Uppsatsnivå: D
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Hellström, Per Anders Rickard. "Wireless Wearable Measurement System Based on Pedobarography for Monitoring of Health." Licentiate thesis, Mälardalens högskola, Inbyggda system, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-32101.
Повний текст джерелаАнотація:
Health care costs have increased over the last decades due to an ageing population. Therefore, research in personal health monitoring (PHM) has increased in response to this. PHM has advantages such as mobility (monitoring of health at work or at home), early detection of health problems enabling preventive health measures and a reduction of health care cost. Human motion analysis, using for example inertial measurement units and pedobarography, is an important subcategory of PHM. Pedobarography (PBG) is the study of pressure fields acting between the plantar surface of the foot and a supporting surface. Gait and posture analysis, prosthetics evaluation and monitoring of recovery from injury or disease are examples of PBG applications. Portable PBG can be performed using force sensing resistors built into the insole inside the shoe. In accordance with this, the research goal for this licentiate thesis is to design, build and evaluate a wireless wearable measurement system based on pedobarography for monitoring of health. In order to fulfil the objectives of the research, literature studies were done and problems with existing in-shoe system solutions were identified. Thus, it was found that further opportunities existed for new designs of PBG systems which take these problems into account. Cross-sectional test case studies were used for validation. The research area is multidisciplinary and encompasses biomedical measurements, electronics and computer science. The main research contributions include design and implementation of a PBG measurement system consisting of commercial off the shelf components, a novel method for selecting measurement samples for weight estimation of carried load during walk, and a novel method for analysing walking intensity using force-time integrals at the toe-off phase of the step. The research results suggest that the new PBG system, in combination with the two novel analysing methods, are suitable for use in wearable systems for monitoring of health. Personal health measurements are done to help decision making related to health. Thus, the future work will strive towards designing different decision support systems.Kostnaderna för vår hälsovård har ökat de senaste årtiondena på grund av att vi lever allt längre. Till följd av detta har forskning inom personlig hälsomonitorering (PHM) ökat. PHM medför fördelar såsom rörlighet (hälsoövervakning på jobbet och i hemmet), tidig upptäckt av hälsoproblem medför möjlighet till åtgärd i ett tidigt skede samt en minskning av kostnaderna för hälsovård. Analys av människors rörelser, med hjälp av till exempel tröghetsmätare och pedobarografi, är en viktig underkategori inom PHM. Pedobarografi (PBG) är studien av tryckfält som uppstår på grund av krafter som verkar mellan fotens undersida och en uppbärande yta. Analys av gångstil och kroppshållning, utvärdering av proteser samt monitorering av återhämtning från skada eller sjukdom är exempel på tillämpningar av PBG. Portabel PBG kan exempelvis utföras med hjälp av resistiva kraftsensorer implementerade i skors inläggssulor. I överrensstämmelse med detta är målet för forskningen i den här licentiatavhandlingen att designa, bygga och utvärdera ett trådlöst bärbart mätsystem baserat på pedobarografi för övervakning av hälsa. För att uppfylla forskningsmålet utfördes litteraturstudier och problem med existerande skobaserade system identifierades. Tvärsnittsstudier användes vid valideringen. Forskningsområdet är tvärvetenskapligt och omfattar biomedicinska mätningar, elektronik och datavetenskap. De främsta vetenskapliga bidragen inkluderar design och implementering av ett pedobarografiskt mätsystem bestående av öppet tillgängliga komponenter, en ny metod för att välja ut uppmätta värden för uppskattning av vikt av buren last under gång, samt en ny analysmetod för gångintensitet med hjälp av kraft-tidsintegraler i stegets avstampsfas. Forskningsresultaten implicerar att det nya pedobarografisystemet, i kombination med de två nya analysmetoderna, är lämpliga att användas i bärbara system för övervakning av hälsa. Mätningar vid personlig hälsomonitorering utförs för att hjälpa till vid beslutsfattande som rör hälsa. Följaktligen strävar framtida forskning mot design av olika beslutsstödsystem.
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Sanders, James P. "Novel sedentary behaviour measurement methods : application for self-monitoring in adults." Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/25182.
Повний текст джерелаАнотація:
With the introduction of the technological age, increasing mechanisation has led to labour saving devices which have all-but engineered physical activity out of our lives and sedentary behaviour has now become the default behaviour during waking hours. Interventions that previously focused on improving levels of physical activity are now attempting to concurrently increase levels of physical activity and decrease time spent in sedentary behaviour. One method that has shown promise in interventions to increase physical activity and healthy eating in adults is the behaviour change technique of self-monitoring. There is now a robust set of literature indicating self-monitoring as the most promising behaviour change technique in this area. Self-monitoring is tied inherently into the recent rise in wearable technology. These new devices have the ability to track a variety of behavioural and physiological parameters and immediately make the information returnable to the user via connected mobile applications. The potential pervasive nature of these technologies and their use of robust behaviour change techniques could make them a useful tool in interventions to reduce sedentary behaviour. Therefore the overall purpose of this three study dissertation was to identify and validate technology that can self-monitor sedentary behaviour and to determine its feasibility in reducing sedentary behaviour. Study 1 Purpose: The aim of this study was to review the characteristics and measurement properties of currently available self-monitoring devices for sedentary behaviour and/or physical activity. Methods: To identify technologies, four scientific databases were systematically searched using key terms related to behaviour, measurement, and population. Articles published through October 2015 were identified. To identify technologies from the consumer electronic sector, systematic searches of three Internet search engines were also performed through to October 1st, 2015. Results: The initial database searches identified 46 devices and the Internet search engines identified 100 devices yielding a total of 146 technologies. Of these, 64 were further removed because they were currently unavailable for purchase or there was no evidence that they were designed for, had been used in, or could readily be modified for self-monitoring purposes. The remaining 82 technologies were included in this review (73 devices self-monitored physical activity, 9 devices self-monitored sedentary time). Of the 82 devices included, this review identified no published articles in which these devices were used for the purpose of self-monitoring physical activity and/or sedentary behaviour; however, a number of technologies were found via Internet searches that matched the criteria for self-monitoring and provided immediate feedback on physical activity (ActiGraph Link, Microsoft Band, and Garmin Vivofit) and sedentary behaviour (activPAL VT, the LumoBack, and Darma). Conclusions: There are a large number of devices that self-monitor physical activity; however, there is a greater need for the development of tools to self-monitor sedentary time. The novelty of these devices means they have yet to be used in behaviour change interventions, although the growing field of wearable technology may facilitate this to change. Study 2 Purpose: The aim of this study was to examine the criterion and convergent validity of the LumoBack as a measure of sedentary behaviour compared to direct observation, the ActiGraph wGT3X+ and the activPAL under laboratory and free-living conditions in a sample of healthy adults. Methods: In the laboratory experiment, 34 participants wore a LumoBack, ActiGraph and activPAL monitor and were put through seven different sitting conditions. In the free-living experiment, a sub-sample of 12 participants wore the LumoBack, ActiGraph and activPAL monitor for seven days. Validity were assessed using Bland-Altman plots, mean absolute percentage error (MAPE), and intraclass correlation coefficient (ICC). T-test and Repeated Measures Analysis of Variance were also used to determine any significant difference in measured behaviours. Results: In the laboratory setting, the LumoBack had a mean bias of 76.2, 72.1 and -92.3 seconds when compared to direct observation, ActiGraph and activPAL, respectively, whilst MAPE was less than 4%. Furthermore, the ICC was 0.82 compared to the ActiGraph and 0.73 compared to the activPAL. In the free-living experiment, mean bias was -4.64, 8.90 and 2.34 seconds when compared to the activPAL for sedentary behaviour, standing time and stepping time respectively. Mean bias was -38.44 minutes when compared to the ActiGraph for sedentary time. MAPE for all behaviours were < 9%, and the ICC were all > 0.75. Conclusion: The LumoBack has acceptable validity and reliability as a measure of sedentary behaviour. Study 3 Purpose: The aim of this study was to explore the use of the LumoBack as a behaviour change tool to reduce sedentary behaviour in adults. Methods: Forty-two participants (≥25 years) who had an iPhone 4S or later model wore the LumoBack without any feedback for one week for baseline measures of behaviour. Participants then wore the LumoBack for a further five weeks whilst receiving feedback on sedentary behaviour via a sedentary vibration from the device and feedback on the mobile application. Sedentary behaviour, standing time, and stepping time were objectively assessed using the LumoBack. Differences in behaviour were determined between baseline, week 1 and week 5. Participant engagement with the LumoBack was determined using Mobile app analytics software. Results: There were no statistically significant differences in behaviour between baseline and the LumoBack intervention period (p > 0.05). Participants engaged most with the Steps card on the LumoBack app with peaks in engagement seen at week 5. Conclusion: This study indicates that using the LumoBack on its own was not effective in reducing sedentary behaviour in adults. Self-monitoring and feedback may need to be combined with other behaviour change strategies such as environmental restructuring to be effective. General Conclusion This thesis found that there are currently an abundance of technologies which self-monitors physical activity but a lack of devices which measuring sedentary behaviour. One such device, the LumoBack, has shown to have acceptable validity as a measure of sedentary behaviour. Whilst the use of the LumoBack as a behaviour change tool did not elicit any significant changes, its ability to be a pervasive behavioural intervention and the use of user-defined nudging can make the LumoBack, and other similar low cost, valid objective sedentary behaviour self-monitors key components in multi-faceted interventions.
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Alharbi, Sami Hamad. "Measurements and monitoring of naturally occurring radioactive materials for regulation." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/98122/1/Sami_Alharbi_Thesis.pdf.
Повний текст джерелаАнотація:
This project investigated the measurement of naturally occurring radioactive material. Such measurements are usually conducted to demonstrate compliance with the national and international requirements for radiation protection. The thesis reviewed the current regulation of these radioactive materials and identified the key regulatory challenges that relevant authorities face when implementing or establishing a regime for NORM. Limitations on the measurement of the release of radon (a radioactive gas) from surfaces were determined. The parameters influencing radon and thoron levels in indoor environments were investigated. The potential use of a broad energy germanium detector for the application of NORM was examined.
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Knoll, Thomas Martin, and Marcus Eckert. "Demo on Network-based QoE measurement for Video streaming services." Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-147676.
Повний текст джерелаАнотація:
Progressive download video services, such as YouTube, are responsible for a major part of the transmitted data volume in the Internet and it is expected, that they also will strongly affect mobile networks. Streaming video quality mainly depends on the sustainable throughput achieved during transmission. In order to achieve an acceptable video quality in mobile networks (with limited capacity resources), traffic engineering mechanisms have to be applied. For that, the streaming video quality needs to be measured and monitored permanently. Therefore, the video timestamps which are encoded within the payload of the TCP segments have to be extracted. For that it is necessary to decode the video within the transported payload. Algorithms for decoding Flash Video, MP4 and WebM Video have already been implemented as a demonstration implementation in support of the network based measurement contribution to SG12 by Chemnitz University for TCP encoded progressive download Internet services. In the demonstration, the derived play out buffering from the monitored traffic is being output internally. A second application is then used to graphically display the estimation result. The measurement and estimation is solely done within a measurement point of an operator network without access to the client’s end device.
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Taylor, Malcolm G. "Measurement of organic substances in the gas phase using on-line electrochemical techniques." Thesis, Loughborough University, 1988. https://dspace.lboro.ac.uk/2134/12597.
Повний текст джерелаАнотація:
Aniline was chosen as an atmospheric pollutant which might be monitored using an electrochemical sensor. The effect of pH and of different organic solvents on electrode poisoning was investigated for the analysis of aniline by voltammetry and it was concluded that it was not possible to prevent poisoning of the electrode by the reaction products. The analysis of aniline by flow injection analysis (fia) with DC (constant potential) and pulsed (double pulse) amperometric detection also suffered from electrode poisoning and the latter had a relatively high detection limit. Secondary and tertiary substituted anilines with similar volatilities to aniline at room temperature were examined as suitable alternatives to aniline using voltammetry. Dimethyl-p-toluidine poisoned the electrode to a small extent when analysed by voltammetry. Detection of this compound by fia with pulsed amperometric detection showed improved electrode stability but was not judged suitable for long term monitoring of atmospheric samples of the amine. A satisfactory method for monitoring aniline on line was developed using fia with triple pulse amperometric detection (PAD). The PAD waveform was optimised with respect to a low detection limit and a degree of selectivity towards possible atmospheric interferents for the detection of aniline in dilute aqueous acid at a platinum electrode. A wall jet cell was designed for the analysis of aniline vapour in air which was continuously trapped in dilute acid and periodically injected into a fia system. The cell was not affected by small gas bubbles and was reasonably portable.
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Cook, Daniel Adam. "Monitoring small fatigue cracks using ultrasonic surface waves." Thesis, Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/17381.
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Elsmore, Chris. "Neighbourhood Watch : social resource monitoring." Thesis, Swansea University, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.678659.
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Zhang, Ruizhi. "ARTERIAL WAVEFORM MEASUREMENT USING A PIEZOELECTRIC SENSOR." VCU Scholars Compass, 2010. http://scholarscompass.vcu.edu/etd/126.
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This study aims to develop a new method to monitor peripheral arterial pulse using a PVDF piezoelectric sensor. After comparing different locations of sensor placement, a specific sensor wrap for the finger was developed. Its composition, size, and location make it inexpensive and very convenient to use. In order to monitor the effectiveness of the sensor at producing a reliable pulse waveform, a monitoring system, including the PZT sensor, ECG, pulse-oximeter, respiratory sensor, and accelerometer was setup. Signal analysis from the system helped discover that the PZT waveform is relative to the 1st derivative of the artery pressure wave. Also, the system helped discover that the first, second, and third peaks in PZT waveform represent the pulse peak, inflection point, and dicrotic notch respectively. The relationship between PZT wave and respiration was also analyzed, and, consequently, an algorithm to derive respiratory rate directly from the PZT waveform was developed. This algorithm gave a 96% estimating accuracy. Another feature of the sensor is that by analyzing the relationship between pulse peak amplitude and blood pressure change, temporal artery blood pressure can be predicted during Valsalva maneuver. PZT pulse wave monitoring offers a new type of pulse waveform which is not yet fully understood. Future studies will lead to a more broadly applied use of PZT sensors in cardiac monitoring applications.
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Michaud, Jon-Pierre 1955. "A timed exposure diffusive sampler for air monitoring in epidemiology." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277211.
Повний текст джерелаАнотація:
A timed exposure diffusive sampler (TEDS) sensitive enough to measure hourly averages of nitrogen dioxide (NO2) at low parts per billion levels was developed for use in epidemiological studies. TEDS can be used for a variety of atmospheric pollutants. TEDS was tested in the laboratory against known concentrations of NO2 and against well established NO2 measurement systems. It was then tested in the field against the Environmental Protection Agency's reference method for measuring NO2. The TEDS method appears well suited to epidemiological investigations of air quality and extends previous work in this area by offering improved time resolution of changes in pollutant concentration at a cost sufficiently low to permit its use in large scale studies. The TEDS method also shows potential for miniaturization for use in personal sampling.
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Zhong, Zhian. "Power Systems Frequency Dynamic Monitoring System Design and Applications." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/28707.
Повний текст джерелаАнотація:
Recent large-scale blackouts revealed that power systems around the world are far from the stability and reliability requirement as they suppose to be. The post-event analysis clarifies that one major reason of the interconnection blackout is lack of wide area information. Frequency dynamics is one of the most important parameters of an electrical power system. In order to understand power system dynamics effectively, accurately measured wide-area frequency is needed. The idea of building an Internet based real-time GPS synchronized wide area Frequency Monitoring Network (FNET) was proposed to provide the imperative dynamic information for the large-scale power grids and the implementation of FNET has made the synchronized observations of the entire US power network possible for the first time. The FNET system consists of Frequency Disturbance Recorders (FDR), which work as the sensor devices to measure the real-time frequency at 110V single-phase power outlets, and an Information Management System (IMS) to work as a central server to process the frequency data. The device comparison between FDR and commercial PMU (Phasor Measurement Unit) demonstrate the advantage of FNET. The web visualization tools make the frequency data available for the authorized users to browse through Internet.
The research work addresses some preliminary observations and analyses with the field-measured frequency information from FNET. The original algorithms based on the frequency response characteristic are designed to process event detection, localization and unbalanced power estimation during frequency disturbances. The analysis of historical cases illustrate that these algorithms can be employed in real-time level to provide early alarm of abnormal frequency change to the system operator. The further application is to develop an adaptive under frequency load shedding scheme with the processed information feed in to prevent further frequency decline in power systems after disturbances causing dangerous imbalance between the load and generation.Ph. D.
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Weiss, Peter. "Interferometric of monitoring laser-induced spallation for the measurement of coating adhesion /." Zürich, 1994. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=10803.
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Hampton, David D. Lembke Erica S. "The effects of progress monitoring in early writing using curriculum-based measurement." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/4955.
Повний текст джерелаАнотація:
Thesis (M.A.)--University of Missouri-Columbia, 2007.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on October 26, 2007) Vita. Includes bibliographical references.
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Foo, Ki Fung Kelvin. "Real time voltage stability monitoring by Thevenin impedance estimation with local measurement." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/4652.
Повний текст джерелаАнотація:
As modern power systems operate closer to the limits due to load growth and financial imperatives, voltage stability becomes a more important issue and there have been more incidents caused by voltage collapse. For example, there have been 11 outages affecting more than 4000MW between 1984 and 2000 in North America [1]. In power systems, load voltages decrease as the supplied loads increase until the maximum power transfer point is reached. The voltage will collapse if the load is increased above this limit. Therefore, it is important to monitor the loadability of a system to avoid voltage collapse.
The loadability of a system can be calculated when the Thevenin impedance is available as the maximum power transfer occurs when the Thevenin impedance and the load impedance are the same in magnitude. This thesis suggests a method to estimate the Thevenin impedance of a system. ABB corporation suggests the Voltage Stability Predictor (VIP) method to estimate the Thevenin impedance, but there are problems with this method and it is not gaining popularity in industry. In this thesis, a method is suggested to estimate the Thevenin impedance by taking advantage of the existance of negative sequence components in the system.
The concept of this method has been proved mathematically. Simulations were performed on simple systems and on the modified IEEE 13 bus power flow test case to verify the feasibility of the method and the results are promising. Then, the method was verified with field measurements for a 25kV substation. The voltages and currents were analyzed to estimate the Thevenin equivalent impedance of the power system and the results were compared with the design Thevenin equivalent impedance. The result confirms the viability of the method as the estimated Thevenin impedance matched the design value.
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Jayawardene, Kanishka. "A human head motion monitoring system based on an inertial measurement unit." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=110713.
Повний текст джерелаАнотація:
This thesis describes the design and implementation of a human head motion monitoring system based on an inertial measurement unit. The system is to be used by physicians to characterize the head motion when engaging in day-to-day activities before and after corrective surgery is performed on the vestibular system. This system is also to be used by personnel in sports medicine to compare performance between athletes and by coaches to help athletes improve their techniques.The design is implemented using an inertial measurement unit with an accelerometer, a gyroscope, and a magnetometer. Data can be logged on an onboard micro-SD card while transmitting data and receiving commands wirelessly. In doing so, several signal processing techniques such as finite impulse response filters and sensor fusion using Kalman filters are presented. All sensors are calibrated to ensure accuracy and reliability. In addition, this thesis focuses on pattern recognition techniques based on the Bayesian classification method to distinguish different daily activities of users.Cette thèse décrit la conception et le développement d'une système d'enregistrement des mouvements de la tête reposant sur une unité de mesure inertielle. Le système doit être utilisé par des médecins pour caractériser les mouvements de tête avant et après une chirurgie correctrice effectuée sur le système vestibulaire alors que le patient est engagé dans ses activités journalières. Ce système doit également être utilise en médecine du sport afin de comparer les performances entre athlètes et les entraîneurs pour aider les athlètes à améliorer leurs techniques.Le système comprend une unité de mesure inertielle avec un accéléromètre trois axes, un gyroscope et un magnétomètre. Les données peuvent être enregistrées sur une carte micro-SD lors de la transmission de données et recevoir des commandes sans fil. Ce faisant, plusieurs techniques de traitement du signal tels que des filtres à réponse impulsionnelle finie et la fusion de signaux en utilisant des filtres de Kalman sont présentés. Tous les capteurs sont étalonnés pour garantir l'exactitude absolue. De plus, cette thèse se concentre sur les techniques de reconnaissance de forme basée sur la méthode de classification Bayesienne pour distinguer les différents activités quotidiennes des utilisateurs.
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Raper, Tyson B. "In-season Drought Monitoring| Testing Instrumentation and Developing Methods of Measurement Analysis." Thesis, University of Arkansas, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3626302.
Повний текст джерелаАнотація:
Soil moisture sensor use in crop production systems has the potential to give inference on plant water status for the purpose of irrigation scheduling and site-drought characterization. These processed measurements could serve as the framework on which to compile trial results across locations, thereby more accurately defining varietal yield response to drought. Still, the ability to characterize drought within a given field or initiate irrigations from these data hinge upon the ability of the instrument to characterize soil moisture at the sampled point and extrapolate that information across the landscape and time. Therefore, the objectives of this research were to: (1) test the response of the Watermark 200SS (Irrometer Company, Inc., Riverside, CA) and Decagon 10HS (Decagon Devices, Inc., Pullman, WA) to changes in water content of three dissimilar soils representing common soils in row-crop production under variable environmental conditions; (2) develop a soil moisture-based index to quantify drought stress in dryland cotton cultivar trials; and (3) determine if a limited number of soil moisture sensors deployed into a dryland cultivar trial could accurately characterize the VWC at a given point within the field and if this measurement could be extrapolated out to the field scale from the very small sphere of influence characterizing the utilized soil moisture sensors. During the 2012 and 2013 growing seasons soil moisture sensors were deployed into over 14 cotton cultivar trials across the U.S. Cotton Belt and into a water-input controlled container study. Tested sensors' inability to accurately predict container VWC emphasized the relatively small quantity of soil on which these sensors rely and the variability in soil moisture within a very limited volume. Results from the drought-index studies suggested both the Accumulated Soil Moisture Stress Index (ASMSI) and the relative reduction in evapotranspiration (1-(ETc adj/ETc)) appear to have potential in characterizing the amount of stress experienced within dryland cultivar trials. Analysis of spatial and temporal stability suggested trends between sensors were consistent, but absolute node readings varied. Optimism concerning the potential of these measurements/approaches for increasing water use efficiency is coupled with a call for more arbitrary, universal methods of measurement analysis.
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Al-Faysale, Muaiad Shawqi Murad. "Measurement, condition monitoring and flow modification in light-phase pneumatic conveying systems." Thesis, University of Bradford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.253472.
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Upton, David Mark. "An automated monitoring system for the production and measurement of metal fatigue." Master's thesis, University of Cape Town, 1988. http://hdl.handle.net/11427/8324.
Повний текст джерелаАнотація:
Includes bibliography.New equipment for producing and following the fatigue process, in metals, has been developed. The specimens, which must be in the shape of tuning forks, are resonated at high amplitudes. This is achieved by attaching small, powerful, samarium-cobalt magnets to the ends of the tynes, enabling them to be driven efficiently by a "U"-core electromagnet. A small, piezoceramic strain gauge provides a method of picking up the vibrations. To maintain resonance, the signal is used in a positive feedback loop, which incorporates an analogue multiplier to provide AGC. This also keeps the amplitude constant at any desired level, throughout the duration of an experiment.
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Meyer, Eric Todd. "Evaluation of exhaust flowrate measurement techniques for a mobile emissions monitoring system." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1855.
Повний текст джерелаАнотація:
Thesis (M.S.)--West Virginia University, 2001.Title from document title page. Document formatted into pages; contains xii, 89 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 67-68).
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Van, der Zee Pieter. "Measurement and modelling of the optical properties of human tissue in the near infrared." Thesis, University of London, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319667.
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Waterfall, Paul. "High accuracy video measurement systems for structural monitoring : an investigation of the measurement opportunities and barriers to widespread adoption." Thesis, University of Bristol, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.690775.
Повний текст джерелаАнотація:
Video cameras have been used within the structural research community for decades, particularly for assessing movement of hard to reach areas such as bridge decks and cables. Displacement measurements have correlated well with electro-mechanical sensors and demonstrated time and cost savings. The technique has not found a substantial market within t he civil engineering community, which at first glance is unexpected given the advantages reported and the proliferation of camera-based measurements in other fields. This thesis investigates the capabilities of video measurement (with particular emphasis on Imetrum), and how they fit with in Structural Monitoring. Extensive interviews and collaborative working with organisations involved in monitoring UK structures and some overseas has identified stakeholder requirements. Barriers to adoption have been identified and investigated, as well as work done to overcome them. Fundamental experimental work (mostly field based) has enabled an in depth understanding of the factors that are specific to using video based measurement systems outdoors - surface finish; size of virtual targets used by the tracking software; impact of various weather conditions and the impact of using different optics on image quality (and hence measurement resolution). Field studies and project work have been undertaken to understand the practical benefits and limitations of applying video measurement systems, including for load testing of bridges; train induced displacement of rail track systems and longer term (1 month plus) static monitoring of bridges and tunnels. This research has shown that there are areas where a video based system is a valuable addition to the toolbox of those responsible for constructing, assessing and maintaining the UKs infrastructure, particularly where access is difficult and/or absolute displacement at speeds from 1- 300Hz required. This thesis also demonstrates this in some projects that have been paid for at commercial rates by infrastructure owners, as a proof of tangible benefit.
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Marsh, Gabriel. "Fatigue load monitoring of offshore wind turbine support structures." Thesis, University of Strathclyde, 2016. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=28278.
Повний текст джерелаАнотація:
The uptake of renewable energy sources has increased dramatically in recent decades, in response to the contribution to climate change attributed to CO2 emissions from the burning of fossil fuels, the need for governments to maximise the use of domestic energy forms with depleting conventional sources, and to reduce exposure to fuel price volatility. Renewable energy targets set by the European Union have been supported by legislation and economic incentives, and have resulted in a sharp increase in installed wind power capacity in particular. Wind power is seen as a particularly attractive source of renewable energy capacity in the UK due to favourable resources and a competitive cost of energy for onshore sites, with 8.8 GW of capacity currently installed [1]. Constraints from visual and environmental impacts, together with improved wind resources, have led to the acceptance of greater financial costs and the exploitation of offshore sites, with over 5 GW installed to date [1]. Both onshore and offshore, the wind industry now has significant operational experience, with some of the earliest wind farms approaching the end of their design life. Material fatigue is a design critical factor which dictates the safe operational life of wind turbines, but is subjected to numerous areas of uncertainty in the level of environmental loading and structural response, as well as material properties and manufacturing methods. Therefore, a conservative design must be ensured from the outset, which presents the potential for fatigue life extension of installed assets if improved knowledge of their operational experience can be obtained. This thesis details the methodology for a fatigue load assessment of operational offshore wind turbine support structures using measured data, and attempts to quantify areas of loading which contribute to total fatigue damage. The methodologies developed build on existing recommendations for onshore wind turbines to incorporate the additional effects of the offshore environment. Results from measured loading suggest that design fatigue levels can be reduced if operational monitoring is included. Operational experience can allow design conservatism, which is necessary due to uncertainties in structural properties and in levels of stochastic loading, to be more accurately quantified.
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Flodquist, Gail Linnea. "MEASUREMENT OF TOE TEMPERATURE AS AN EARLY INDICATOR OF ALTERATIONS IN PERIPHERAL PERFUSION (MONITORING, SHOCK)." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275349.
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