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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Performance Improvement Methods for Terrain Database Integrity Monitors and Terrain Referenced Navigation

Vadlamani, Ananth Kalyan 13 July 2004 (has links)
No description available.
122

APPLICATION OF IMAGE ANALYSIS TECHNIQUES IN FORWARD LOOKING SYNTHETIC VISION SYSTEM INTEGRITY MONITORS

Kakarlapudi, Swarna 20 July 2004 (has links)
No description available.
123

Design of an image radiation monitor for ILS glide slope in the presence of snow

Marcum, Frank January 1995 (has links)
No description available.
124

Integrated Global Positioning System and inertial navigation system integrity monitor performance

Harris, William M. January 2003 (has links)
No description available.
125

Measurement of Body Postures and Movements in Adults with Cerebral Palsy

Claridge, Everett January 2017 (has links)
Aim: To determine the criterion validity of the Activ8a and VitaMoveb activity monitors (AM) in measuring body postures and movements (P&M) in adults with spastic cerebral palsy (CP) with different gross motor functional abilities in a simulated free-living environment. Methods: In this observational validation study participants were included between March and June 2016. Participants were divided into two groups: ambulatory and non-ambulatory adults (wheelchair users). For ambulatory adults, three Activ8 monitors (attached to the frontal thigh, lateral thigh, and in the pant pocket) and three synchronized VitaMove monitors (attached to the chest and each leg) were worn while participants were video recorded when performing a standardized activity protocol. For non-ambulatory adults, two synchronized Activ8 monitors (attached to the dominant wrist and wheelchair wheel) and three VitaMove monitors (attached to the chest and each wrist) were worn while participants were video recorded when performing a standardized wheelchair protocol. A native Dutch student provided standardized instructions while the author video recorded participants. Activities were performed in a movement laboratory and simulated free-living environment. Output data of the Activ8 and the VitaMove monitors were compared with video observation as a criterion measure. Absolute and relative time differences were calculated for each detected body P&M and for total measurement time for each participant. The following body P&M categories were detected: sitting, standing, walking, running, cycling, wheelchair driving, active upper body (stable wheelchair), and assisted driving. Agreement between the Activ8 and VitaMove during activity measurement was determined for each activity using Spearman Rho correlation coefficients, which were then compared with Meng’s test. Adapted Bland-Altman plots were completed to determine agreement at an individual level and Wilcoxon Signed-Rank tests were calculated to evaluate differences between detected P&M time across measures. Relative time differences of <10% between measures were indicative of acceptable validity. Results: Fifteen adults with spastic CP [10 men; mean(SD) age, 35.7(13) years; Gross Motor Function Classification System distribution: level I (n=6), level II (n=5), level III (n=3), level IV (n=1)] were included. For ambulatory adults (n=14), criterion validity of the Activ8 at the lateral thigh location during basic and complex daily life activities was moderate to good (average relative time differences: 0.25% for sitting, 4.69% for standing, 2.46% for walking, 3.19% for cycling, and 1.96% for light-to-moderate upright activity), except for running (34.6% average difference) The criterion validity of the VitaMove was acceptable, with the exception of standing and running (average relative time differences: 1.69% for sitting, 12.3% for standing, 4.84% for walking, 9.70% for cycling, 23.8% for running, and 0.91% for light-to-moderate upright activity). Spearman Rho correlation coefficients were significantly greater between video/lateral thigh Activ8 than video/frontal thigh Activ8 and video/pant pocket Activ8 for P&M categories sitting, basic standing, basic walking, and light-to-moderate upright activity (p<0.01 for all). Moreover, Spearman Rho correlation coefficients were significantly greater between video/Activ8 than video/VitaMove for basic walking and light-to-moderate upright activity P&M categories (p<0.01). In non-ambulatory, wheelchair users (n=3), the Wheelchair Activ8 demonstrated greater validity than the VitaMove monitor, when compared to video observation, for the detection of sedentary upper body and active upper body behaviours. Conclusion: The Activ8, positioned on the lateral thigh, demonstrates adequate validity as a tool for monitoring of body P&M during free-living activities in ambulatory adults with spastic CP. The Activ8 demonstrated superior validity as a direct measure of body P&M compared to the VitaMove AM. The sample size of non-ambulatory adults was small (n=3) and allowed for descriptive and exploratory analysis only; therefore, validity of the Wheelchair Activ8 for has to be further examined in a larger number of participants. Clinical relevance: The Activ8 and Wheelchair Activ8 shows promise as a clinical measurement tool of physical behaviour for adults with CP across GMFCS levels I-IV. The Activ8 could be used in the future development of health promotion initiatives, due to the features of goal setting and user feedback, while providing researchers greater insight in activity data than consumer-grade AMs. Suppliers: a. Activ8, trademark of Remedy Distribution Ltd. (original equipment manufacturer is 2M Engineering Ltd.), John F Kennedylaan 3, 5555XC, Valkenswaard, The Netherlands b. VitaMove, 2M Engineering Ltd., John F Kennedylaan 3, 5555XC, Valkenswaard, The Netherlands / Thesis / Master of Science (MSc)
126

The deep-sea gorgonian coral Primnoa resedaeformis as an oceanographic monitor

Sherwood, Owen 06 December 2017 (has links)
<p> Primnoa resedaeformis is a deep-sea gorgonian coral with worldwide distribution and a lifespan of at least several hundred years. Recent work has suggested that it may be possible to obtain extended, high-resolution records of ambient oceanographic conditions from Primnoa skeletons. This thesis focuses on specimens recently collected live from the Northeast Channel, SW of Nova Scotia, from depths of 300-500m. </p> <p> Skeletal microstructure was examined as a prerequisite to geochemical sampling. Skeletons exhibit periodic growth at three distinct scales. Concentric annual rings throughout the skeleton, and sub-annual laminae in the horny axis, measure 200 +1-100 microns and 15 +1-10 microns, respectively. Fine-scale striae in the outer calcite cortex measure 1.5 +1-2 microns. The dark, gorgonin-rich portion of annual rings in the horny axis forms in winter, when currents in the NE Channel are most energetic. Growth in these animals is apparently tied to the passage of currents at seasonal, lunar and tidal frequencies. Annual ring widths in the horny axis could not be successfully cross-dated, however, a prominent dark ring that appears to have been formed in 1976 is present in several of the colonies examined. Prominent dark rings may serve as useful benchmarks in sclerochronology. </p> <p> Mg/Ca and Sr/Ca were measured by laser ablation ICP-MS in the predominantly calcite axial cortex. Across a 1.5°C gradient, Mg/Ca is positively related to temperature. Sr/Ca also increases with temperature, but this may be explained by the influence of Mg/Ca on Sr partitioning, rather than temperature. Near annual-resolution timeseries profiles of Mg/Ca are consistent within and among colonies having different growth rates. Conversion of Mg/Ca profiles to temperatures using a provisional calibration [Mg/Ca (mmollmol) = 4.88(+/-1.09) T (°C) + 70.92 (+/-6.79)] yields a range of values and trends that are consistent with the observational data. Mg/Ca in Primnoa, therefore, is a viable means of monitoring bottom-water temperatures. The North Atlantic Oscillation (NAO) is responsible for a significant component of inter-annual temperature variability in the Scotia-Maine region. Mg/Ca records from older corals could therefore provide extended proxy records of the NAO. </p> / Thesis / Master of Science (MSc)
127

Design and testing of a prototype in-line chip quality monitor

Auel, John B. 10 June 2009 (has links)
This project involved the design and testing of a prototype in-line chip quality monitor for gathering process control information for the manufacturers of wood chips. This monitor specifically addresses three common complaints with current chip sampling procedures. Chip sampling occurs too late in the process. It is inadequate. It is too infrequent to develop management information. The monitor is composed of a double screen drum separator to divide chips into oversize, accepts, and pins/fines. Counterbalanced tip buckets are used to weigh each size class. Tip bucket cycles are recorded by a computer via magnetic proximity switches attached to each bucket. This information is then used to chart production of chip size classes, updated continuously over the sorting period. This monitor is capable of sorting one ton of chips per hour. Two trials were conducted to test the monitor. One in a lab environment, and one on site at a chip mill. Both trials compared monitor output with independent samples classified using a Williams classifier. The trials showed that outputs were consistent with Williams output. This monitor can effectively chart chip distribution information. This process control information provides the manufacturer with immediate knowledge of chipper performance. / Master of Science
128

Evaluating Coliform Monitoring Strategies for Contamination Scenarios in a Distribution System Model

Bauer, Jeremy 28 May 2008 (has links)
Large public water utilities currently are required to take several 100 mL water samples every month in their distribution systems and to test these samples for the presence of total coliforms to comply with the Total Coliform Rule. How and where they take these samples is not specified. The Total Coliform Rule is currently undergoing review and revision. One possible revision is more specific rule language or guidance of where and when utilities take their monthly coliform water samples. This project considers various drinking water distribution system monitoring strategies for a large drinking water utility using simulations within an EPANET computer model of that utility's distribution system. A review of the literature and the use of best professional judgment help to inform the understanding of the primary causes of the occurrence of coliform bacteria in drinking water distribution systems. In this analysis, both contamination scenarios and coliform monitoring approaches are simulated in the EPANET computer model to better understand what types of contamination events might be detected by routine coliform monitoring and to what extent monitoring strategies affect observed results. In addition, statistical strengths of the various strategies and their respective results are considered in this project. Analysis of model output supports the assertion that water age may be a good factor to consider in designing a monitoring plan, especially if sampling cannot be conducted every day and that taking samples immediately after and in the vicinity of rapid changes in flow (e.g., during a firefighting incident) may help utility operators to better understand what associated risk, if any, exists to consumers of drinking water as a result of these flow conditions. / Master of Science
129

Entwicklung einer Methode zur Pre-Aktivitäts- und Dosisleistungsberechnung von reaktornahen Bauteilen auf Basis von Neutronenfluenzverteilungen – EMPRADO: Teilprojekt A: Berechnung der Neutronenfluenzverteilung in reaktornahen Bauteilen und deren Validierung an Experimenten als Basis der Aktivitätsrechnungen

Konheiser, J., Barkleit, A. 19 December 2024 (has links)
On the basis of an exact power history and accurate geometric modelling, plant-specific neutron fluences were calculated for in each case a pre- and convoy unit of German nuclear power plant for reactor components and for concrete and structural elements close to the reactor. These neutron fluences are the basis for determining the generated activation of the construction materials during the power operation of the plant. The calculations were supported by an extensive measurement program in the last cycles of two plants, where neutron fluence values were determined ex-perimentally with the help of activation foils (monitors). A spectral analysis was possible by using different monitor materials. The monitors were measured by gam-ma spectrometry after sampling using a high-purity germanium (HP-Ge) detector. The comparison of the calculated and measured activities shows, with a few excep-tions, good to very good agreement between the values. This means that the real ratios of neutron radiation in the elements were calculated very well and the method and model can be used to determine the activity distribution. Due to the possibility of the accurate simulation of the resulting activities on the ba-sis of these 'best estimate' calculations, detailed planning of the decommissioning can already begin during the operation of the plant. It is not necessary to wait until extensive sampling after the shutdown. In addition, the accurate mathematical determination of the activity distribution in the components enables improved cut planning and thus minimization of the waste volume for the final storage. A further advantage would be that the necessary exper-imental activity determinations could be reduced to a few samples thanks to the supporting experiments and thereby validated neutron fluence calculations.
130

Sistemas de esterilização por plasma: estudos de compatibilidade em polímeros e eficácia esterilizante em produtos médico-hospitalares de calibres reduzidos e longa extensão / Plasma sterilization: study of polymer compatibility and sterilization effectiveness in long and narrow lumen medical devices

Oliveira, Débora Cristina de 19 March 2007 (has links)
Recentes avanços nas ciências médicas têm contribuído significativamente para que novas tecnologias de materiais e processos tecnológicos ganhem espaço. No âmbito da esterilização de materiais poliméricos termossensíveis, empregados na fabricação de ampla gama de produtos médico-hospitalares, os processos que operam sob temperaturas compatíveis com estes materiais, gás óxido de etileno e radiação ionizante, agregam desvantagens importantes envolvendo, respectivamente, aspectos de toxicidade ocupacional, ambiental e ao paciente, bem como alterações intrínsecas aos mesmos. O processo inovador e potencialmente compatível por gás plasma representa promissora alternativa, onde o agente letal agrega entidades altamente reativas provenientes de gás ionizado por aplicação de descarga elétrica e originalmente desprovido de atividade microbicida. O presente trabalho teve por objetivo proceder a estudos que permitam conhecimento da eficácia esterilizante de processos empregando plasma de O2 puro e sua mistura com H2O2 em produtos médico-hospitalares de natureza polimérica, configuração tubular, longa extensão e calibre reduzido. Os lumens desses materiais foram preenchidos com suportes vítreos (lamínulas de 8 x 18mm) intencionalmente contaminados com biocargas restritas de Bacillus subtilis var. niger ATCC 9372, que atuaram como biosensores, constituindo os monitores biológicos. Esses dispositivos foram submetidos a ciclos por plasma sob distintas combinações de parâmetros envolvendo distintos sistemas (RIE e ICP), potências de rádio-freqüência e tempos de exposição sub-letais. Após os ciclos esterilizantes, os monitores biológicos foram abertos e submetidos à análise microbiológica para a enumeração de possíveis esporos sobreviventes, usando o método do número mais provável (NMP), possibilitando o cálculo dos valores D (principal parâmetro de resistência de uma população microbiana). Adicionalmente, foram objeto de investigação polímeros distintos utilizados na confecção de produtos médico-hospitalares, a fim de esclarecer a influência do plasma sobre as características intrínsecas desses materiais. Foram selecionados o poli (cloreto de vinila) - PVC, polietileno de alta densidade (HDPE), polipropileno (PP), poliuretano (PUR) e policarbonato (PC). As amostras foram expostas em ambos sistemas de plasma (RIE e ICP) usando gás O2 puro e sua mistura gasosa O2/H2O2, potências de RF de 150W e 300W e tempo de exposição de 30 min. As amostras foram submetidas a espectroscopia fotoacústica no infravermelho, microscopia eletrônica de varredura, microanálise e perfilometria a fim de avaliar possíveis danos aos polímeros expostos, assim como citotoxicidade in vitro para esclarecer sobre a biocompatibilidade dos mesmos. Os resultados demonstraram que a eficácia esterilizante do plasma foi dependente do calibre dos monitores biológicos e das potências de RF aplicadas. Os menores valores D foram obtidos para os monitores biológicos de maior calibre (7mm) e potências de 150W/300W em ambos sistemas RIE e ICP, respectivamente. A mistura gasosa O2/H2O2 apresentou maior efeito microbicida quando comparada ao O2 puro em ambos sistemas de plasma. Paralelamente, a exposição ao plasma levou à modificação em nível superficial (oxidação e aumento da rugosidade) para todos os polímeros expostos. Foi observado efeito mais agressivo quando usando plasma gerado em sistema ICP usando mistura gasosa O2/H2O2. Os dados sugerem que a massa interna ou bulk de todos as amostras não foi afetada, assim como as alterações observadas não promoveram modificação na biocompatibilidade dos polímeros estudados. / The sterilization of heat sensitive materials like medical devices made of polymers has been under intense investigation regarding new technologies and sterilization agents, as far as mechanical problems and innocuity of currency processes such as ionizing radiation and ethylene oxide gas, respectively, are concerned. Plasma sterilization of medical devices is emerging as an attractive substitute to conventional sterilization technologies, once is recognized as an atoxic and low-temperature process. It uses different gases that are activated by an electrical discharge, generating reactive species which promote lethal effect on microorganisms. In this work, it was performed experimental studies to evaluate the sterilization effectiveness of pure O2 and O2/H2O2 mixture gas plasma against a standard load of 103 Bacillus subtilis var. niger ATCC 9372 spores inoculated on 8 x 18mm glass carriers placed inside and in central position of PVC catheters 64cm long with internal diameters of 7mm and 1mm. These assemblages simulated the challenge of medical devices as biological monitors. The gas plasma sterilization efficiency was studied as a function of plasma systems (RIE and ICP), radio frequency powers and sub-lethal exposition times. After sterilization, the biological monitors were disassembled and the survivors were growth in trypticase soy broth using the most probable number (MPN) technique. Hence, it was possible to calculate the time D required to decrease a given population by a factor of 10 (90% reduction). On the other hand, there was a need to evaluate the safety of plasma sterilization in terms of polymer damage. Materials used in this study were: polyvinylchloride (PVC), high density polyethylene (HDPE), polypropylene (PP), polyurethane (PUR) and polycarbonate (PC). Samples were exposed to pure O2 and O2/H2O2 plasma sterilization using both plasma systems (RIE and ICP), radio frequency powers of 150W/300W and exposition time of 30 minutes. Fourier transform infrared photoacoustic spectroscopy (FT-IR/PAS), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and profilometry, which are surface and bulk characterization techniques, were used to study plasma sterilization polymers compatibility, as well as \"in vitro\" citotoxicity to acess the biocompatibility of exposed polymers. The results demonstrated that plasma antimicrobial activity depended on the inside catheters diameter and radio frequency powers. The smallest D values were obtained when using biological monitors of 7mm of internal diameter and 150W/300W of RF powers, in, respectively, RIE/ICP systems. The mixture O2/H2O2 exhibited higher microbicidal efficacy than pure O2 in both plasma systems. In addition, both plasma systems led to near-surface layers modification, with the increase of roughness and surface oxidation of all the polymers studied. ICP system and O2/H2O2 mixture were more effective to induce the surface modifications observed. The bulk of all polymers showed not to be affected by all plasma conditions used and the surface alterations did not affected the biocompatibility of all the polymers studied.

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