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Formative evaluation subject selection : FD/I cognitive style /Chinien, Christian Alex January 1987 (has links)
No description available.
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Field dependence and susceptibility to social influence /Gary, Melvin Lee January 1967 (has links)
No description available.
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Análise do comportamento de sensores EGFET como função do tempo, iluminação, área da superfície e temperatura / Analysis of the behavior of EGFET sensor as a function of time, illumination, surface área and temperature.Fernandes, Jessica Colnaghi 03 October 2011 (has links)
O transistor de efeito de campo de porta estendida (EGFET) é um dispositivo composto por uma membrana sensível a íons e um MOSFET comercial, que pode ser aplicado para a medição do teor de íons em uma solução. O filme fino de óxido de estanho dopado com flúor (FTO) foi utilizado como a membrana seletiva do EGFET, e todo o sistema foi utilizado como sensor de pH. Os sensores de pH desenvolvidos a partir de transistores de efeito de campo (FETs) detectam o campo elétrico criado pelos íons da solução. A alteração do pH no organismo afeta a estrutura e a atividade das macromoléculas biológicas, por isso a detecção da alteração do pH no organismo é de grande importância. O objetivo deste trabalho foi o estudo da influência de alguns agentes externos sobre o FTO para ser utilizado como membrana sensível a íons do EGFET como sensor de pH. O sensor padrão apresentou uma resposta linear no escuro por volta de 37 mV/pH, para uma área de membrana de 230 mm2 . Foram estudados o efeito da evolução da medida no tempo, o efeito da iluminação, o efeito da alteração da área de contato do filme fino de FTO com a solução de pH e o efeito da alteração da temperatura da solução de pH. Para as medições feitas no escuro a dependência do tempo foi diferente das medições feitas na presença de luz UV-VIS. Para pHs ácidos a presença da luz faz com que o valor da corrente Ids diminua em relação a mesma medição no escuro enquanto que para pHs básicos, o valor da corrente aumenta. A sensibilidade na presença da luz altera em torno de 10%. Para o estudo do efeito da área foram utilizadas duas formas diferentes de medições, sendo a primeira forma utilizando diferentes áreas da mesma amostra e a segunda forma utilizando áreas diferentes para diferentes amostras. O aumento da temperatura da solução aumenta o valor da corrente do sensor em até 5% e aumenta a sensibilidade em 60%. / The extended gate field effect transistor (EGFET) is a device composed of a conventional ion sensitive electrode and a commercial MOSFET device, which can be applied for the measurement of ion content in a solution. The fluorine-doped tin oxide thin film (FTO) is used as a sensitive membrane of the EGFET, and the whole system was used as a pH sensor. The pH sensor developed from field effect transistors (FTO) detect the electric field created by the ions of the solution. Changing the pH in the body affects the structure and activity of biological macromolecules, and the detection of pH change in the body is of great importance. The aim of this paper was study the influence of some external agents in the FTO for used as ion sensitive membrane EGFET as pH sensor. The standard sensor presented a linear response in the dark about 37 mV/pH, for a membrane area of 230 mm2 . Was studied the effect of the evolution of the measure in time, the illumination effect, the effect of changing the contact area of the FTO thin film with the solution pH and the effect of changing the temperature of the pH solution. For measurements in the dark the time dependence is different than for the case under UV-VIS illumination. For acids solutions the light presence causes a current value decreases over the same measurement in the dark, whereas for basic solution the current values increases. The sensitivity in light presence changes around 10%. To study the area effect two different studies was applied. The first measure was using different areas of the same sample and the second measure was using different areas of different samples. Increasing the solution temperature the current value of the sensor also increases and the sensitivity increase about 60%.
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In-vivo radiation diode dosimetry for therapeutic photon beamsSaini, Amarjit Singh 01 June 2007 (has links)
In-vivo dosimetry with diode detectors is used in radiation therapy as a quality assurance tool. The diode sensitivity under radiation depends upon temperature, dose rate and SDD (source-to-detector distance), field size, beam angle, and energy. This dissertation presents the first systematic and quantitative study of dosimetric characteristics for most of the commercial radiation diodes (n-type and p-type) under different radiation beams.In the temperature dependence study, the systematic study on the dose rate dependence of svwt (sensitivity variation with temperature) was performed. It was concluded that sufficient preirradiation can eliminate dose rate dependence of svwt. However, preirradiation cannot eliminate dose rate dependence of the diode sensitivity, S, itself. In the dose rate and SDD dependence study, it was shown that the p-type diodes do not always show less dose rate dependence than the n-type diodes.
Preirradiation does not always reduce diode dose rate dependence. SDD dependence of diode sensitivity can be explained by the instantaneous dose rate dependence if sufficient buildup is provided to eliminate electron contamination. An empirical formula was proposed to fit the dose rate dependence of diode sensitivity. In the energy dependence study, the energy dependence diode detectors are quantified. The empirical theory to quantify this effect was developed. Monte Carlo simulation and the cavity theory are used to predict the energy dependence. It was concluded that the energy dependence does not depend on whether the diode is n- or p- type but rather depends mainly on the material around the die (buildup and its geometry).
A systematic study of the correction factors for accurate diode dosimetry is presented in this dissertation.This dissertation has established a theoretical foundation for the modeling of the transient electric and radiation properties of the diode detectors, separately. We believe that the Monte Carlo simulations code for radiation transport should be coupled with the continuity equations to describe the charge transport in the diode detector, and thus provides a complete quantitative description of dosimetric characteristics of the diode detectors. The ultimate goal is to use the diode detector as an absolute dosimeter, rather than as a relative dosimeter.
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Análise do comportamento de sensores EGFET como função do tempo, iluminação, área da superfície e temperatura / Analysis of the behavior of EGFET sensor as a function of time, illumination, surface área and temperature.Jessica Colnaghi Fernandes 03 October 2011 (has links)
O transistor de efeito de campo de porta estendida (EGFET) é um dispositivo composto por uma membrana sensível a íons e um MOSFET comercial, que pode ser aplicado para a medição do teor de íons em uma solução. O filme fino de óxido de estanho dopado com flúor (FTO) foi utilizado como a membrana seletiva do EGFET, e todo o sistema foi utilizado como sensor de pH. Os sensores de pH desenvolvidos a partir de transistores de efeito de campo (FETs) detectam o campo elétrico criado pelos íons da solução. A alteração do pH no organismo afeta a estrutura e a atividade das macromoléculas biológicas, por isso a detecção da alteração do pH no organismo é de grande importância. O objetivo deste trabalho foi o estudo da influência de alguns agentes externos sobre o FTO para ser utilizado como membrana sensível a íons do EGFET como sensor de pH. O sensor padrão apresentou uma resposta linear no escuro por volta de 37 mV/pH, para uma área de membrana de 230 mm2 . Foram estudados o efeito da evolução da medida no tempo, o efeito da iluminação, o efeito da alteração da área de contato do filme fino de FTO com a solução de pH e o efeito da alteração da temperatura da solução de pH. Para as medições feitas no escuro a dependência do tempo foi diferente das medições feitas na presença de luz UV-VIS. Para pHs ácidos a presença da luz faz com que o valor da corrente Ids diminua em relação a mesma medição no escuro enquanto que para pHs básicos, o valor da corrente aumenta. A sensibilidade na presença da luz altera em torno de 10%. Para o estudo do efeito da área foram utilizadas duas formas diferentes de medições, sendo a primeira forma utilizando diferentes áreas da mesma amostra e a segunda forma utilizando áreas diferentes para diferentes amostras. O aumento da temperatura da solução aumenta o valor da corrente do sensor em até 5% e aumenta a sensibilidade em 60%. / The extended gate field effect transistor (EGFET) is a device composed of a conventional ion sensitive electrode and a commercial MOSFET device, which can be applied for the measurement of ion content in a solution. The fluorine-doped tin oxide thin film (FTO) is used as a sensitive membrane of the EGFET, and the whole system was used as a pH sensor. The pH sensor developed from field effect transistors (FTO) detect the electric field created by the ions of the solution. Changing the pH in the body affects the structure and activity of biological macromolecules, and the detection of pH change in the body is of great importance. The aim of this paper was study the influence of some external agents in the FTO for used as ion sensitive membrane EGFET as pH sensor. The standard sensor presented a linear response in the dark about 37 mV/pH, for a membrane area of 230 mm2 . Was studied the effect of the evolution of the measure in time, the illumination effect, the effect of changing the contact area of the FTO thin film with the solution pH and the effect of changing the temperature of the pH solution. For measurements in the dark the time dependence is different than for the case under UV-VIS illumination. For acids solutions the light presence causes a current value decreases over the same measurement in the dark, whereas for basic solution the current values increases. The sensitivity in light presence changes around 10%. To study the area effect two different studies was applied. The first measure was using different areas of the same sample and the second measure was using different areas of different samples. Increasing the solution temperature the current value of the sensor also increases and the sensitivity increase about 60%.
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Enhancement of Thermally Injected Spin Current through an Antiferromagnetic InsulatorLin, Weiwei, Chen, Kai, Zhang, Shufeng, Chien, C. L. 05 May 2016 (has links)
We report a large enhancement of thermally injected spin current in normal metal (NM)/antiferromagnet (AF)/yttrium iron garnet (YIG), where a thin AF insulating layer of NiO or CoO can enhance the spin current from YIG to a NM by up to a factor of 10. The spin current enhancement in NM/AF/YIG, with a pronounced maximum near the Neel temperature of the thin AF layer, has been found to scale linearly with the spin-mixing conductance at the NM/YIG interface for NM = 3d, 4d, and 5d metals. Calculations of spin current enhancement and spin mixing conductance are qualitatively consistent with the experimental results.
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Links between pain sensitivity and alcohol dependenceZelmanova-Witkin, Yuliya 07 November 2014 (has links)
Scientists have long wondered why some individuals are more sensitive to pain than others. While individual differences in pain have traditionally been discounted due to neuroticism, research has shown that individuals who are more sensitive to pain demonstrate real biological differences in pain perception (Coghill, McHaffie & Yen, 2003). However, individual differences in pain sensitivity remain under-explored in research and clinical settings that can provide further insights into clinical disorders such as addiction. The current research review is interested in examining the link between pain sensitivity and alcohol dependence. Investigating the relationship between pain sensitivity and alcohol addiction prompts many important peripheral questions such as whether increased pain sensitivity can serve as a useful biomarker for alcohol addiction, and how addiction to alcohol can cause changes in sensitivity to pain. Addiction potential or risk for addiction is a research area that is extremely important given that the high rate of addiction in this country is alarmingly high. The literature is sparse on the relationship between hyperalgesia or pain sensitization and risk for alcohol addiction. This literature review synthesizes current relevant research on pain and addiction, as well as addressing possible links between them. / text
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Electro-optic studies of the flexoelectric effect in chiral nematic liquid crystalsMusgrave, Bronje January 2000 (has links)
No description available.
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Evaluation of Law Enforcement and the Court System in Texas: Perspectives of Adult Protective Services Case ManagersWeaver, Matthew S. 05 1900 (has links)
The purpose of this study was to examine perceptions of Texas Adult Protective Services (APS) case managers (CM) in regard to their relationships with the law enforcement community and area courts. The sample consisted of 138 Texas APS CMs. The survey measured respondents' perceived strengths and weaknesses of their relationships with both the law enforcement community and with area courts. Items also included respondents' interest in receiving additional training and their perceptions of level of job-readiness of newly hired APS CMs. Data were analyzed quantitatively using SAS. Findings of the survey revealed high ratings of perceived teamwork on the part of the CM are associated with high relationship ratings with both area courts and law enforcement. Findings also revealed that high ratings of perceived autonomy on the part of the CM are associated with lower relationship ratings with law enforcement personnel but not with area courts.
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Recovery after completion of inpatient substance abuse treatment program in the Western Cape: An exploratory study on self-efficacy differencesMalanguka, Gashinje January 2018 (has links)
Magister Psychologiae - MPsych / Recent increases in intellectual, social, infrastructural and economic resources available for the treatment of substance related mental disorders in the Western Cape reflects the national surge towards health promotion and eradication of the burden created by substance abuse. This large number of people who relapse and return to active substance abuse after receiving treatment obstruct this aim. This study aimed to determine the differences in self efficacy and assess for the risk for relapse during the first twelve months of recovery. Albert Bandura’s social cognitive theory provided a suitable framework for the objectives of this study. A cross-sectional survey research design was implemented. Research participants were recruited from different aftercare groups across Western Cape using cluster sampling. The sample consisted of 105 English literate, consenting adult residents of Western Cape who completed an inpatient substance abuse rehabilitation program within twelve months spanning April 2014- April 2015. Data was collected from respondents using two instruments; a demographic information sheet, and an adapted alcohol abstinence self-efficacy scale (AASE). This instrument showed high validity and reliability during a pilot study conducted to ascertain its reliability in a South African sample. Ethics clearance and project registration was given by the Senate Research Committee of the University of the Western Cape. All ethics principles were adhered to and attention was paid particularly to ensuring confidentiality, informed consent, voluntary participation and the right to withdraw without risk of loss or negative consequence. The data was analysed using descriptive statistics, correlation matrices and regression analysis. The results indicated that self-efficacy was highest during the first days and weeks following discharge from a treatment facility. Respondents who remained gainfully employed during recovery reported higher overall self-efficacy and coped better with negative emotions, withdrawal, physical discomfort and urges to use. Respondents’ perceived ability to cope with negative emotions, and resist withdrawal and urges to use again decreased as post-discharge time increased, with females reporting lower self-efficacy than males and respondents’ age showing no significant effect on recovery outcomes. In conclusion, high abstinence self-efficacy has proven to be a predictor of sobriety. After care, interventions can focus on activities to strengthen abstinence self-efficacy levels. Employment stands out as a vital factor to consider in helping people maintain sobriety.
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