Phototransistor
Mostrando 1-11 de 11 artigos, teses e dissertações.
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1. An Amorphous Silicon Photo TFT with Si3N4/Al2O3 or HfO2 Double Layered Insulator for Digital Imaging Applications
Abstract This paper focuses on amorphous silicon photo thin-film transistors with double layered insulator using Si3N4/Al2O3 or HfO2 as candidates for the succession of Si3N4 as a traditional insulator in the fabrication of hydrogenated amorphous silicon thin-film transistors. Whether for industry or for research, there is a need to investigate the use of th
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2019-03
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2. Dispositivo para medir tiempo y temperatura usando un microcontrolador
In this paper a device of data acquisition with low cost and easy management was developed for using in experiments of physics where time or temperature measurement is required. The device is composed by three main parts: (i) sensors to measure the physical variables of time and temperature; (ii) a data acquisition card with microcontroller to manage command
Rev. Bras. Ensino Fís.. Publicado em: 27/11/2017
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3. CARACTERIZAÇÃO DE DISPOSITIVOS ELETRÔNICOS PARA DOSIMETRIA EM TOMOGRAFIA COMPUTADORIZADA. / CHARACTERIZATION OF ELECTRONIC DEVICES FOR DOSIMETRY IN COMPUTED TOMOGRAPHY.
Computed tomography (CT) is an examination of high diagnostic capability that delivers high doses of radiation compared with other diagnostic radiological examinations. The current CT dosimetry is mainly made by using a 100 mm long ionization chamber. However, it was verified that this extension, which is intended to collect all scattered radiation of the si
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 12/03/2012
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4. AvaliaÃÃo dos parÃmetros dosimÃtricos em feixes de FÃtons de Radioterapia usando fototransistor SMT
One of the biggest challenges in radiotherapy dosimetry is to certify that the prescribed dose is given to the patient. For this, it is necessary to use small detectors to evaluate the beam parameters. Current dosimetry is realized with detectors that highlight problems: high cost, difficulty in handling, absence of real time readout, complex and delayed obt
Publicado em: 2008
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5. CMOS image system wiht high responsivity and high dynamic range / Sistemas de imagem CMOS com alta responsividade e elevada faixa dinamica
This thesis adresses two important challenges imposed by CMOS technology trends, the reduction of the junctions s responsivity and voltages levels. A new photodetector with high responsivity and a multi-sampling time domain image system are investigated. This thesis proposes to use the gate controlled lateral bipolar junction transistor (GCLBJT) as a four te
Publicado em: 2008
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6. Development of a photovoltaic pyranometer / Desenvolvimento de um piranÃmetro fotovoltaico
Nesse trabalho foi desenvolvido e testado um piranÃmetro utilizando um sensor Ãptico à base de silÃcio cristalino, facilmente encontrado no mercado. O sensor foi envolvido por uma estrutura de PVC com a finalidade de minimizar os efeitos tÃrmicos e das intempÃries sobre suas medidas de irradiÃncia solar. Um difusor, tambÃm à base de PVC, foi incorpo
Publicado em: 2008
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7. Characterization of NPN-phototransistor for x-ray diagnostic spectrometry / CaracterizaÃÃo de fototransistor NPN para espectrometria de raios-x diagnÃstico
Este trabalho apresenta um estudo inicial a respeito da utilizaÃÃo de fototransistores bipolares de junÃÃo como dispositivo de mediÃÃo de energias de fÃtons de raios-X na faixa de diagnÃstico. O fototransistor à analisado a partir da resposta da corrente de coletor em funÃÃo da corrente de base durante a irradiaÃÃo do dispositivo com fÃtons de
Publicado em: 2007
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8. Dosimetria em tomografia computadorizada utilizando fototransistor / Dosimetry in computed tomography using phototransistor
O aumento do uso da tomografia computadorizada (CT) na prÃtica mÃdica e a dose relativamente alta proporcionada ao paciente fazem da CT um forte contribuinte na dose populacional em radiologia mÃdica. Portanto, existe a necessidade de avaliar e otimizar as doses de radiaÃÃo em CT para os pacientes submetidos a essa tÃcnica de radiodiagnÃstico. A dosim
Publicado em: 2007
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9. Um fotômetro multi-led microcontrolado, portátil e de baixo custo
A microcontrolled, portable and inexpensive photometer is described. It uses six light-emitting diodes (LEDs) as radiation sources and a phototransistor as detector, as well as a microcontroller (PIC - Programmable Controller of Interruption). This device provided total autonomy to the proposed photometer, which was successfully applied to determination of F
Química Nova. Publicado em: 2005-12
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10. Tecnologia para o reconhecimento do formato de objetos tri-dimensionais. / Three dimensional shape recognition technology.
We present in this work a new method for three dimensional Shape Recognition. Traditional Computer Vision systems use bi-dimensional TV camera images. In most of the industrial Robotic applications, the excess of detail obtained by the TV camera is needless. Traditional classification algorithms spend a lot of time to process the excess of information. For t
Publicado em: 1991
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11. Photogating of ionic currents across a lipid bilayer.
Photoformation of metalloporphyrin cations in a lipid bilayer increases the ionic currents of negative and decreases those of positive hydrophobic ions. At low concentrations of the mobile hydrophobic ion, a 30% change in conductivity is observed that decreases with increasing concentration of positive tetraphenylphosphonium ion and increases drastically wit