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Synchronized Phasor Measurement Units : Implementation of PMU Algorithm on HVDC Control PlatformDeo, Samarth January 2013 (has links)
Power Systems most often operate in the margins of stability limits. With power grids becoming even more automated now, Phasor Measurement Units (PMU’s) and Phasor Data Concentrators (PDC’s) become essential for real-time control of the system. Since PMU’s are time synchronized, the phasors can be compared at the substations, studied for any faults and analyzed at the same time. These PMU’s report the measured magnitude, phasor angle of voltages and currents in real synchronized time in different locations. One good way to measure these quantities is to use the Discrete Fourier Transform (DFT) and analyze the signal as a digital signal. However with transients and noise present in the input signal, DFT might not be the best approach for measurement and/or protection. With the IEEE C37.118 (Standard for Synchrophasor for Power Systems) 2011 version emphasizing on the importance of the two classes of PMU’s- P-class for Protection and M-class for Measurement; every vendor now has to label their products with one of these classes. There is a high precision required for P-class PMU’s whereas a good reporting rate for M-class. Recently The North-American Synchrophasor Initiative (NASPI) and Western Electricity Coordinating Council (WECC) also gave filtering specifications and frequency response of an industry compliant PMU. This thesis discusses the various frequency estimation algorithms, which are compliant with the NASPI/WECC standards. Further such an algorithm is implemented on ABB proprietary hardware and tested against dynamic tests.
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BMAA and Neurodegenerative IllnessCox, Paul Alan, Kostrzewa, Richard M., Guillemin, Gilles J. 01 January 2018 (has links)
The cyanobacterial toxin β-N-methylamino-l-alanine (BMAA) now appears to be a cause of Guamanian amyotrophic lateral sclerosis/parkinsonism dementia complex (ALS/PDC). Its production by cyanobacteria throughout the world combined with multiple mechanisms of BMAA neurotoxicity, particularly to vulnerable subpopulations of motor neurons, has significantly increased interest in investigating exposure to this non-protein amino acid as a possible risk factor for other forms of neurodegenerative illness. We here provide a brief overview of BMAA studies and provide an introduction to this collection of scientific manuscripts in this special issue on BMAA.
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Pyruvate Dehydrogenase Kinase 4 Deficiency and Hepatic SteatosisHwang, Byounghoon 23 June 2009 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Regulation of the pyruvate dehydrogenase complex (PDC) is important for glucose homeostasis and control of fuel selection by tissues. Knocking out pyruvate dehydrogenase kinase 4 (PDK4), one of four kinases responsible for regulation of PDC activity, lowers blood glucose levels by limiting the supply of three carbon compounds for gluconeogenesis. Down regulation of PDK4 expression is also important for control of blood glucose by insulin. The primary goal was to determine whether PDK4 should be considered a target for the treatment of diabetes. A major concern is that inhibition of fatty acid oxidation by PDK4 deficiency may promote fat accumulation in tissues and worsen insulin sensitivity. This was examined by feeding wild type and PDK4 knockout mice a diet rich in saturated fat. Fasting blood glucose levels were lower, glucose tolerance was better, insulin sensitivity was greater, and liver fat was reduced in PDK4 knockout mice. The reduction in liver fat is contradictory to the finding that fibrate drugs increase PDK4 expression but ameliorate hepatic steatosis in rodents. To investigate this phenomenon, wild type and PDK4 knockout mice were fed the high saturated fat diet with and without clofibric acid. The beneficial effect of clofibric acid on hepatic steatosis was greater in the PDK4 knockout mice, indicating up regulation of PDK4 is not necessary and likely opposes the effect of clofibric acid on hepatic steatosis. Clofibric acid dramatically lowered the amount of hepatic CD36, a plasma membrane translocase required for fatty acid import, suggesting a novel mechanism for prevention of hepatic steatosis by fibrates. PDK4 deficiency had no effect on CD36 expression but reduced the enzymatic capacity for fatty acid synthesis, suggesting clofibric acid and PDK4 deficiency ameliorate hepatic steatosis by independent mechanisms. Investigation of the mechanism by which insulin regulates PDK4 expression revealed a novel binding site for hepatic nuclear factor 4α (HNF4α) in the PDK4 promoter. The stimulatory effect of HNF4α was sensitive to inhibition by Akt which is activated by insulin. The findings suggest PDK4 is a viable target for the treatment of hepatic steatosis and type 2 diabetes.
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Novel Conceptual Design And Anlysis Of Polymer Derived Ceramic Mems Sensors For Gas Turbine EnvironmentNagaiah, Narasimha 01 January 2006 (has links)
Technical challenges for developing micro sensors for Ultra High Temperature and turbine applications lie in that the sensors have to survive extremely harsh working conditions that exist when converting fuel to energy. These conditions include high temperatures (500-1500°C), elevated pressures (200-400 psi), pressure oscillations, corrosive environments (oxidizing conditions, gaseous alkali, and water vapors), surface coating or fouling, and high particulate loading. Several technologies are currently underdeveloped for measuring these parameters in turbine engines. One of them is an optical-based non-contact technology. However, these nondirective measuring technologies lack the necessary accuracy, at least at present state. An alternative way to measure these parameters without disturbing the working environments is using MEMS type sensors. Currently, the techniques under development for such harsh environment applications are silicon carbide (SiC) and silicon nitrite (Si3N4) based ceramic MEMS sensors. But those technologies present some limitation such as narrow processing method, high cost (materials and processing cost), and limited using temperatures (typically < 800 C). In this research we propose to develop two sensors based on recently developed polymer-derived ceramics (PDCs): Constant Temperature Hot wire Anemometer, temperature/heat-flux sensor for turbine applications. PDC is a new class of high temperature ceramics. As we shall describe below, many unique features of PDCs make them particularly suitable for the proposed sensors, including: excellent thermo-mechanical properties at high temperatures, enable high temperature operation of the devices; various well-developed processing technologies, such as injection molding,photolithography, embossing, DRIE etching and precise machining, can be used for the fabrication of the devices; and tunable electric conductivity, enable the proposed sensors fabricated from similar materials, thus reliability considerations associated with thermal mismatch, which is a big concern when using MEMS-based sensors at elevated temperatures, will be minimized.
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Mathematical modelling of performance and wear prediction of PDC drill bits: impact of bit profile, bit hydraulic, and rock strengthMazen, Ahmed Z., Mujtaba, Iqbal M., Hassanpour, A., Rahmanian, Nejat 14 May 2020 (has links)
Yes / The estimation of Polycrystalline Diamond Compact (PDC) cutters wear has been an area of concern for the drilling industry for years now. The cutter's wear has been measured practically by pulling the bit out for evaluation at the surface. It is important to find the right time for tripping out as this helps to avoid the fishing job and reduces the operational cost significantly. The prediction of the drilling performance is based on the interaction of cutter and rock. Several authors focused on the cutter-rock interface but only a few researchers tried to model the wear of the PDC bit cutters. The aim of this research is to understand the relationships between the rate of penetration (ROP) and the drilling variables per each foot, and then determine the overall bit efficiency for the whole drilling operation. A new mathematical model is derived to predict the PDC bit performance by considering the factors that were already not taken into account. These factors include rock strength, bit design, and bit hydraulic. The model investigates the effect of these parameters to estimate the abrasive cutters wear on the inner and the outer bit cones by deriving modified equations to calculate the mechanical specific energy (MSE), torque, and depth of cut (DOC) as a function of effective blades (EB). The model is used to forecast the bit cutters wear conditions in four wells in the oil fields located in Libya, which were drilled with three different PDC's sizes. The model enables the results to be compared to the actual bit cutters wear measured for inner and outer cones. The results are found that are well in agreement with the actual field data obtained in bit records. / Financial support from ministry of higher education in Libya.
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The Use of the Performance Diagnostic Checklist - Human Services to Assess and Improve Data Reporting in a Community-Based Adult Autism Service ProgramGahman, Kady January 2019 (has links)
For agencies in the health and human services field, data reporting is the primary source of information from which progress and organizational outcomes are measured. Often, front-line staff are responsible for collecting these data and yet are often ill-equipped to collect data accurately and consistently leading to a performance deficit affecting the strength and success of the program. Evaluating and addressing performance issues in the human services field has long been a challenge due to limited resources. Finding an effective and efficient method of evaluation that leads to a function-based intervention would improve performance and ultimately improve organizational outcomes. This study evaluated the Performance Diagnostic Checklist – Human Services (PDC-HS) as means of assessing the performance deficit of inaccurate data reporting in a community-based adult autism services program. A multiple-baseline design was used across four participants to evaluate the effects of the interventions indicated by the PDC-HS. Two participants received performance feedback and two received additional training following the behavior skills training model. Results indicated that both interventions were effective in increasing accurate data reporting across participants. Social validity measures also indicated the PDC-HS was easy to use and could be completed in a timely manner. / Applied Behavioral Analysis
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Impact of type of drug insurance on adherence, persistence and costs of antidepressant drugs : a Quebec population-based studyAssayag, Jonathan 01 1900 (has links)
Contexte: À date, il existe peu de données sur l’adhésion, la persistance et les coûts associés aux antidépresseurs selon le type d’assurance médicament (privé ou public).
Objectif: Comparer selon le régime d’assurance médicament (privé ou public), l'adhésion, la persistance et les coûts des antidépresseurs.
Méthodes de recherche: Une étude de cohorte appariée a été réalisée en utilisant des bases de données du Québec.
Sujets: Nous avons sélectionné 194 patients assurés par un régime privé et 1923 patients assurés par le régime public de la Régie de l’assurance maladie du Québec (RAMQ) (18-64 ans) qui ont rempli au moins une ordonnance pour un antidépresseur entre décembre 2007 et septembre 2009.
Mesures: L’adhésion, mesurée sur une période d’un an, a été estimée en utilisant le proportion of prescribed days covered (PPDC). Un modèle de régression linéaire a été utilisé afin d’estimer la différence moyenne en PPDC entre les patients assurés par un régime privé et ceux assurés par le régime public de la RAMQ. La persistance a été comparé entre ces deux groupes avec un modèle de régression de survie Cox, et le coût mensuel d'antidépresseurs ($ CAN) a été comparé entre ces deux groupes en utilisant un modèle de régression linéaire.
Résultats: Le PPDC parmi les patients assurés par un régime privé était de 86,4% (intervalle de confiance (IC) 95%: 83,3%-89,5%) versus 81,3% (IC 95%: 80,1%-82,5%) pour les patients assurés par le régime public de la RAMQ, pour une différence moyenne ajustée de 6,7% (IC 95%: 3,0%-10,4%). La persistance après un an parmi les patients assurés par un régime privé était de 49,5% versus 18,9% pour les patients assurés par le régime public de la RAMQ (p <0,001), et le rapport de risque ajusté était de 0,48 (IC 95%: 0,30-0,76). Comparativement aux patients assurés par le régime public de la RAMQ, les patients ayant une assurance privée ont payé 14,94 $ CAD (95% CI: $12,30-$17,58) de plus par mois en moyenne pour leurs antidépresseurs.
Conclusion: Les patients assurés par un régime privé avaient une meilleure adhésion, persistance, mais avaient aussi un plus haut coût pour leurs antidépresseurs que ceux assurés par le régime public de la RAMQ. Cette différence de coûts peut être due aux différentes exigences de paiement en pharmacie entre les deux régimes ainsi qu’aux limites des honoraires des pharmaciens imposés par le régime public. / Background: The influence of the type of drug insurance on adherence, persistence and cost of antidepressants is not well known.
Objective: To compare adherence, persistence and cost of antidepressants in patients with private and public drug insurance.
Research Design: A matched cohort study was conducted using prescription claims databases from Quebec, Canada.
Subjects: 194 privately and 1923 publicly insured patients (18-64 years) who filled at least one prescription for an antidepressant between December 2007 and September 2009.
Measures: Adherence over one year was estimated using the proportion of prescribed days covered (PPDC). The difference in mean PPDC between patients with private and public drug insurance was estimated with a linear regression model. Persistence was compared between the groups with a Cox regression model, and the monthly cost of antidepressants (CAD$) was compared between the two groups using linear regression.
Results: The PPDC was 86.4% (95% CI: 83.3-89.5) in patients with private and 81.3% (95%CI: 80.1-82.5) in patients with public drug insurance and the adjusted mean difference was 6.7% (95% CI: 3.0-10.4). Persistence was 49.5% in patients with private and 18.9% in patients with public drug insurance at one year (p<0.001), and the adjusted hazard ratio was 0.48 (95%CI: 0.30-0.76). Patients privately insured paid 14.94$ CAD (95% CI: 12.30; 17.58) more per month on average for their antidepressants.
Conclusion: Better adherence and persistence and higher costs were observed in privately insured patients. Cost difference might be due to different pharmacy payment requirements and pharmacists’ honorary restrictions under the public plan.
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Impact of type of drug insurance on adherence, persistence and costs of antidepressant drugs : a Quebec population-based studyAssayag, Jonathan 01 1900 (has links)
Contexte: À date, il existe peu de données sur l’adhésion, la persistance et les coûts associés aux antidépresseurs selon le type d’assurance médicament (privé ou public).
Objectif: Comparer selon le régime d’assurance médicament (privé ou public), l'adhésion, la persistance et les coûts des antidépresseurs.
Méthodes de recherche: Une étude de cohorte appariée a été réalisée en utilisant des bases de données du Québec.
Sujets: Nous avons sélectionné 194 patients assurés par un régime privé et 1923 patients assurés par le régime public de la Régie de l’assurance maladie du Québec (RAMQ) (18-64 ans) qui ont rempli au moins une ordonnance pour un antidépresseur entre décembre 2007 et septembre 2009.
Mesures: L’adhésion, mesurée sur une période d’un an, a été estimée en utilisant le proportion of prescribed days covered (PPDC). Un modèle de régression linéaire a été utilisé afin d’estimer la différence moyenne en PPDC entre les patients assurés par un régime privé et ceux assurés par le régime public de la RAMQ. La persistance a été comparé entre ces deux groupes avec un modèle de régression de survie Cox, et le coût mensuel d'antidépresseurs ($ CAN) a été comparé entre ces deux groupes en utilisant un modèle de régression linéaire.
Résultats: Le PPDC parmi les patients assurés par un régime privé était de 86,4% (intervalle de confiance (IC) 95%: 83,3%-89,5%) versus 81,3% (IC 95%: 80,1%-82,5%) pour les patients assurés par le régime public de la RAMQ, pour une différence moyenne ajustée de 6,7% (IC 95%: 3,0%-10,4%). La persistance après un an parmi les patients assurés par un régime privé était de 49,5% versus 18,9% pour les patients assurés par le régime public de la RAMQ (p <0,001), et le rapport de risque ajusté était de 0,48 (IC 95%: 0,30-0,76). Comparativement aux patients assurés par le régime public de la RAMQ, les patients ayant une assurance privée ont payé 14,94 $ CAD (95% CI: $12,30-$17,58) de plus par mois en moyenne pour leurs antidépresseurs.
Conclusion: Les patients assurés par un régime privé avaient une meilleure adhésion, persistance, mais avaient aussi un plus haut coût pour leurs antidépresseurs que ceux assurés par le régime public de la RAMQ. Cette différence de coûts peut être due aux différentes exigences de paiement en pharmacie entre les deux régimes ainsi qu’aux limites des honoraires des pharmaciens imposés par le régime public. / Background: The influence of the type of drug insurance on adherence, persistence and cost of antidepressants is not well known.
Objective: To compare adherence, persistence and cost of antidepressants in patients with private and public drug insurance.
Research Design: A matched cohort study was conducted using prescription claims databases from Quebec, Canada.
Subjects: 194 privately and 1923 publicly insured patients (18-64 years) who filled at least one prescription for an antidepressant between December 2007 and September 2009.
Measures: Adherence over one year was estimated using the proportion of prescribed days covered (PPDC). The difference in mean PPDC between patients with private and public drug insurance was estimated with a linear regression model. Persistence was compared between the groups with a Cox regression model, and the monthly cost of antidepressants (CAD$) was compared between the two groups using linear regression.
Results: The PPDC was 86.4% (95% CI: 83.3-89.5) in patients with private and 81.3% (95%CI: 80.1-82.5) in patients with public drug insurance and the adjusted mean difference was 6.7% (95% CI: 3.0-10.4). Persistence was 49.5% in patients with private and 18.9% in patients with public drug insurance at one year (p<0.001), and the adjusted hazard ratio was 0.48 (95%CI: 0.30-0.76). Patients privately insured paid 14.94$ CAD (95% CI: 12.30; 17.58) more per month on average for their antidepressants.
Conclusion: Better adherence and persistence and higher costs were observed in privately insured patients. Cost difference might be due to different pharmacy payment requirements and pharmacists’ honorary restrictions under the public plan.
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Combinaison de thérapie épigénétique et d'immunothérapie pour prévenir la rechute de leucémie lymphoblastique aiguë chez les enfants transplantésDiaz, Mélanie 12 1900 (has links)
No description available.
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Obtaining triple layer polycrystalline diamond compact by HPHT methodMashhadikarimi, Meysam 10 July 2017 (has links)
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Previous issue date: 2017-07-10 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Neste trabalho de pesquisa, foi obtido um compacto de diamante policristalino (PDC), constitu?do de uma camada superior de diamante policristalino sob um substrato de WC-10% em peso de Co e uma interface de WC-20% em peso de Nb/Ni entre as camadas, atrav?s de m?todo de sinteriza??o de alta press?o e alta temperatura (HPHT). Para alcan?ar esse objetivo, foram realizadas tr?s etapas distintas. Na primeira etapa, foi sinterizado o corpo de diamante com um ligante adequado, e foram obtidos os melhores par?metros de sinteriza??o. Na segunda etapa, foi realizado o estudo de diferentes condi??es de sinteriza??o para o substrato de metal duro WC-10% p.Co. E, na terceira e ?ltima etapa, foi produzido, de acordo com os resultados alcan?ados nas etapas anteriores, o compacto de diamante policristalino de camada tripla (PDC). Na primeira etapa, quatro ligantes diferentes foram usados para sinterizar o diamante atrav?s do m?todo HPHT. Os ligantes utilizados foram o Nb/Fe, Nb/Co, Nb/Ni e Nb puro, sendo 10% em peso de ligante utilizado para cada composi??o. A sinteriza??o foi realizada a diferentes temperaturas e sob diferentes press?es e tempos. As amostras obtidas foram analisadas atrav?s das medidas de densidade relativa e dureza, al?m das imagens eletr?nicas de varredura, para encontrar os melhores par?metros de sinteriza??o e ligante. Os estudos mostraram que o Nb apresentou o melhor comportamento, e que os melhores par?metros de sinteriza??o foram: T = 1750 ?C, P = 7,7 GPa, t = 6 minutos. Na segunda etapa, uma mistura em p? de WC-10% em peso de Co foi sinterizado atrav?s de HPHT sob press?o de 7,7 GPa, variando temperatura (1500 ?C, 1600 ?C, 1700 ?C, 1800 ?C, 1900 ?C) e tempo (2 e 3 minutos). As an?lises microestruturais e estruturais foram realizadas atrav?s de MEV/EDS e DRX. Ensaios de dureza, tenacidade (ITF) e de resist?ncia ? compress?o, tamb?m, foram realizados para entender os efeitos de diferentes par?metros de sinteriza??o nas propriedades dos sinterizados, verificando-se densifica??o total das amostras sinterizadas a altas temperaturas. Entretanto, foi observado um crescimento anormal de gr?os para estas mesmas temperaturas. Altos valores de dureza foram observados, aproximadamente, entre 1250 a 1650 HV para todas as amostras sinterizadas. Na terceira etapa, para a obten??o do PDC, uma camada fina de WC-20% em peso de Nb/Ni foi utilizada para a forma??o da interface entre a camada superior de diamante com ligante de Nb pura e o substrato de WC 10% em peso de Co. A sinteriza??o foi feita atrav?s do m?todo HPHT ? temperatura de 1750 ?C sob 7,7 GPa de press?o. Foram utilizados dois tempos diferentes, de 6 min. (tr?s sucessivos 2 minutos) e 9 min. (tr?s sucessivos 3 minutos). A dureza foi medida e os estudos estruturais/microestruturais foram realizados atrav?s de an?lises de MEV/EDS. Em suma, os resultados mostraram que este novo tipo de PDC pode ser produzido com sucesso, usando um novo ligante, o niobio puro, para o diamante, sem qualquer presen?a de grafitiza??o. Verificou-se tamb?m que o uso de uma interface com os mesmos elementos constituintes do substrato e do corpo de diamante sinterizado resultou numa boa ades?o entre as camadas, o que pode resultar em melhor desempenho e melhorar a durabilidade do PDC. / The primary objective of this thesis was to obtain a triple layer polycrystalline diamond compact (PDC) containing a polycrystalline diamond as top layer, a WC 10 wt% Co substrate, and a WC 20 wt% Nb/Ni interface to bond these two layers via high pressure high temperature (HPHT) sintering. To achieve this objective, the project has been done in three different stages. The first stage was producing diamond sintered body with a suitable binder, and finding the best sintering parameters. The second stage of project was done to study the WC 10 wt% Co hardmetal substrate at different sintering conditions, and the third and last stage was done according to the results achieved from previous stages to obtain a triple layer PDC. At the first stage, four different binders were used to sinter diamond under HPHT condition. Binders were Nb/Fe, Nb/Co, Nb/Ni and pure Nb and 10 wt% binder was used. Sintering was carried out at different temperature and under different pressure and holding time. Obtained samples were studies according to relative density, microstructure, and hardness to find the optimum binder and sintering parameters. Studies at this stage showed that Nb is the best binder and T=1750 ?C, 7.7 GPa with holding time more than 6 minutes are the best sintering parameters. At the second stage a powder mixture of WC 10 wt% Co was sintered via HPHT at 1500, 1600, 1700, 1800, and 1900?C under 7.7 GPa pressure for 2 and 3 minutes. Microstructural/structural analyses were performed by SEM/EDS and XRD and hardness, Indentation Fracture Toughness (ITF) and compression tests were also carried out to understand effects of different sintering parameters. At this stage, it was found that full density can achieved for high sintering temperature along with abnormal grain growth. High hardness was observed in range starting from 1250 up to 1650 HV. At the third stage, to obtain PDC, a thin layer of WC 20 wt% Nb/Ni was used as an interface between top layer of diamond with pure Nb binder and WC 10 wt% Co substrate. Sintering was done via HPHT method at 1750?C under 7.7 GPa of pressure. Two different holding time of 6 (three successive 2 minutes) and 9 (three successive 3 minutes) were used. Hardness was measured and microstructural/structural studies were done via SEM/EDS. The overall results showed that this new kind of PDC can successfully produce using a new pure Niobium binder for diamond without any graphitization. It was also found that using an interface having the resemblance to both substrate and sintered diamond body caused good adhesion between layers that can results in enhanced performance and improving durability of PDC.
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