ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / Accurate temperature measurement is an essential requirement in modern aircraft data acquisition systems. Both thermocouples and Platinum resistance temperature detectors (RTD) are used for this purpose with the latter being both more accurate and more repeatable. To ensure that only the sensor limits the accuracy of a temperature measurement, end-to-end system accuracy forward of the sensor, should be significantly greater than that of the sensor itself. This paper describes a new digital signal processing (DSP) based system for providing precision RTD based temperature measurements with laboratory accuracy in an aviation environment. Advantages of the new system include, true 3-wire RTD measurement, linear temperature output, on-board ultra-precision resistance standards and transparent dynamic calibration.

The project consists of controlling a mechanical piston and thermal resistance using an Arduino’s microcontroller. The piston and the thermal resistance take part of an existing project. This project, known as The electronic nose, has the purpose to measure the aroma of different products. In order to achieve this purpose, this tool is a combination of various sensors used to detect gases by generating signals for an analysis system. The project can be divided in different parts; electrical circuit design of piston and thermal resistance, design mechanical parts and components needed, develop a software able to control the piston and the thermal resistance and communication between software. The piston is installed on the bottom part of hollow cylindrical case and the thermal resistance is located inside a cylindrical base. This base, where the sample for smelling is put up, is bound on the top of the piston. Arduino controls the piston up and down movement and the temperature in the sample’s base. On the other hand, the electronic nose is installed at the top of the case. Through its sensors, The electronic nose is able to measure the aroma of some products. The aroma comes from the gases of the sample and they can be detected by the sensors. The purpose of installing the piston in the electronic nose is to get a pulse signal during the measure of these gases. Moreover, is very important keep the temperature of the sample under control, therefore the software is based on a on/off controller. A on/off controller calculates continuously the difference between a desired temperature set point and the temperature measured during process. In order to minimize this difference value the controller turn on or off the resistance during a specific instant time.

Made available in DSpace on 2014-06-12T17:39:52Z (GMT). No. of bitstreams: 2 arquivo6973_1.pdf: 6103079 bytes, checksum: 7535f9a6f839bc8c1f2bd30a09d8d241 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2006 / Foram desenvolvidas etapas de processo para fabricação de estruturas resistivas planares e circuitos de condicionamento com conversores e microcontroladores para a construção de sensores inteligentes de temperatura. O objetivo é integrar esse sensor a um sistema capaz de medir pressão para utilizar essas medidas na estimativa da vazão em ambientes agressivos, como em poços de petróleo. Para a medição da temperatura foi escolhida a tecnologia RTD planar, por poder ser fabricada utilizando técnicas de microeletrônica, o que permite projetar sua integração com outras partes do circuito em um mesmo chip ou como circuito híbrido em substrato cerâmico, além de ser de fabricação mais simples e precisa, permitindo fabricação em larga escala, reduzindo custos. O processo de fabricação foi realizado utilizando sistema de litografia óptica e evaporadora disponíveis na sala limpa do Laboratório de Dispositivos e Nanoestruturas. Para esse protótipo foi escolhido o níquel como material transdutor. Para melhorar as características do dispositivo, assim como diminuir a variância, aplicou-se técnicas de otimização estatística de processos. O RTD fabricado foi caracterizado quanto às dimensões, utilizando microscopia óptica e eletrônica e a resistividade foi caracterizada pela técnica das quatro pontas de prova, utilizando um impedancímetro. A avaliação do desempenho do RTD fabricado com relação à variação de temperatura foi realizada através de uma estação de testes com temperatura variável construída, auxiliada por impedancímetro e termopar calibrado. Nessa caracterização observou-se uma variação bastante linear do valor da resistência com a temperatura, próximo de valores obtidos com RTD comerciais, utilizados para comparação. Implementou-se uma configuração de sensor inteligente utilizando-se conversor analógico-digital e o microcontrolador PIC-16F88

InP-based InAlAs/InGaAs pseudomorphic High Electron Mobility Transistors (pHEMTs) have shown outstanding performance; this makes them prominent in high frequency mm-wave and submillimeter-wave applications. However, conventional InGaAs/InAlAs pHEMTs have major drawbacks, i.e., very low breakdown voltage and high gate leakage current. These disadvantages degrade device performance, especially in Monolithic Microwave Integrated Circuit (MMIC) low noise amplifiers (LNAs). The optimisation of InAlAs/InGaAs epilayer structures through advanced bandgap engineering offers a key solution to the problem. Concurrently, device modelling plays a vital role in the design and analysis of pHEMT devices and circuit performance. In this research, two-dimensional (2D) physical modelling of 1 m and sub-micro metre gate length strained channel InAlAs/InGaAs/InP pHEMTs has been developed, in ATLAS Silvaco. All modelled devices were optimised and validated by experimental devices, which were fabricated at the University of Manchester. An underlying device physics insight is gained, i.e., the effect of changes to the device's physical structure, theoretical concepts and its general operation, and a reliable pHEMT model is obtained. The kink anomalies in the I-V characteristics were reproduced. The 2D simulation results demonstrate an outstanding agreement with measured DC and RF characteristics. The aim of developing linear and non-linear models for sub-micro metre transistors and their implementation in MMIC LNA design is achieved with the 0.25 m In0.7Ga0.3As/In0.52Al0.48As/InP pHEMT. An accurate method for the extraction of empirical models for the fabricated active devices has been developed, and optimised using the Advance Design System (ADS) software. The results demonstrate excellent agreement between experimental and modelled DC and RF data. Precise models for MMIC passive devices are also obtained, and incorporated in the proposed design for a single- and double-stage MMIC LNAs at C- and X-band frequencies. The single-stage LNA is designed to achieve a maximum gain ranging from 9 to 13 dB over the band of operation, while the gain is increased to between 20 dB and 26 dB for the double-stage LNA designs. A noise figure of less than 1.2 dB and 2 dB is expected, for the C- and X-band LNAs respectively, while retaining stability across all frequency bands. Although the RF performance of pHEMT is being vigorously pushed towards the terahertz (THz) region, novel devices such as the Resonant Tunnelling Diode (RTD) are needed to support future ultra-high-speed, high-frequency applications. Hence, the study of physical modelling is extended to quantum modelling of an advanced In0.8Ga0.2As/AlAs RTD device. The aim is to effectively model both large-size and submicron RTDs, using Silvaco's ATLAS software to reproduce the peak current density, peak-to-valley-current ratio (PVCR), and negative differential resistance (NDR) voltage range. The physical modelling for the RTD devices is optimised to achieve an excellent match with the fabricated RTD devices; variations in the spacer thickness, barrier thickness, quantum well thickness and doping concentration are included.

Em um reator nuclear PWR a temperatura do refrigerante do circuito primário e a da água de realimentação são medidas usando RTD (Resistance Temperature Detectors), ou termômetros de resistência. Estes RTDs alimentam os sistemas de controle e segurança da usina e devem, portanto, ser muito precisos e ter bom desempenho dinâmico. O tempo de resposta dos RTDs é caracterizado por um parâmetro denominado de Constante de Tempo, definido como sendo o tempo que o sensor leva para atingir 63,2% do seu valor final após sofrer uma variação de temperatura em forma de degrau. Este valor é determinado em laboratório, porém as condições de operação de reatores nucleares são difíceis de ser reproduzidas. O método LCSR (Loop Current Step Response), ou teste de resposta a um degrau de corrente, foi desenvolvido para medir remotamente o tempo de resposta dos RTDs. A partir desse teste, a constante de tempo do sensor é calculada através de uma transformação LCSR que envolve a determinação das constantes modais do modelo de transferência de calor. Este cálculo não é simples e requer pessoal especializado. Por este motivo, utilizou-se a metodologia de Redes Neurais Artificiais para estimar a constante de tempo do RTD a partir do LCSR. Os testes LCSR foram usados como dados de entrada da RNA; os testes de Imersão Rápida foram usados para determinar a constante de tempo dos sensores, sendo estes os valores desejados de saída da rede. Esta metodologia foi aplicada inicialmente a dados teóricos, simulando dez sensores com diferentes valores de constante de tempo, resultando em um erro médio de aproximadamente 0,74 %. Dados experimentais de 3 diferentes RTDs foram usados para estimar a constante de tempo, resultando em um erro máximo de 3,34 %. Os valores de constante de tempo estimados pelas RNAs foram comparados com aqueles obtidos pelo método tradicional, obtendo-se um erro médio de 18 % o que mostra que as RNAs são capazes de estimar a constante de tempo de uma forma precisa. / In a PWR nuclear power plant, the primary coolant temperature and feedwater temperature are measured using RTDs (Resistance Temperature Detectors). These RTDs typically feed the plants control and safety systems and must, therefore, be very accurate and have good dynamic performance. The response time of RTDs is characterized by a single parameter called the Plunge Time Constant defined as the time it takes the sensor output to achieve 63.2 percent of its final value after a step change in temperature. Nuclear reactor service conditions are difficult to reproduce in the laboratory, and an in-situ test method called LCSR (Loop Current Step Response) test was developed to measure remotely the response time of RTDs. From this test, the time constant of the sensor is identified by means of the LCSR transformation that involves the dynamic response modal time constants determination using a nodal heat-transfer model. This calculation is not simple and requires specialized personnel. For this reason an Artificial Neural Network has been developed to predict the time constant of RTD from LCSR test transient. It eliminates the transformations involved in the LCSR application. A series of LCSR tests on RTDs generates the response transients of the sensors, the input data of the networks. Plunge tests are used to determine the time constants of the RTDs, the desired output of the ANN, trained using these sets of input/output data. This methodology was firstly applied to theoretical data simulating 10 RTDs with different time constant values, resulting in an average error of about 0.74 %. Experimental data from three different RTDs was used to predict time constant resulting in a maximum error of 3,34 %. The time constants values predicted from ANN were compared with those obtained from traditional way resulting in an average error of about 18 % and that shows the network is able to predict accurately the sensor time constant.

Em um reator nuclear PWR a temperatura do refrigerante do circuito primário e a da água de realimentação são medidas usando RTD (Resistance Temperature Detectors), ou termômetros de resistência. Estes RTDs alimentam os sistemas de controle e segurança da usina e devem, portanto, ser muito precisos e ter bom desempenho dinâmico. O tempo de resposta dos RTDs é caracterizado por um parâmetro denominado de Constante de Tempo, definido como sendo o tempo que o sensor leva para atingir 63,2% do seu valor final após sofrer uma variação de temperatura em forma de degrau. Este valor é determinado em laboratório, porém as condições de operação de reatores nucleares são difíceis de ser reproduzidas. O método LCSR (Loop Current Step Response), ou teste de resposta a um degrau de corrente, foi desenvolvido para medir remotamente o tempo de resposta dos RTDs. A partir desse teste, a constante de tempo do sensor é calculada através de uma transformação LCSR que envolve a determinação das constantes modais do modelo de transferência de calor. Este cálculo não é simples e requer pessoal especializado. Por este motivo, utilizou-se a metodologia de Redes Neurais Artificiais para estimar a constante de tempo do RTD a partir do LCSR. Os testes LCSR foram usados como dados de entrada da RNA; os testes de Imersão Rápida foram usados para determinar a constante de tempo dos sensores, sendo estes os valores desejados de saída da rede. Esta metodologia foi aplicada inicialmente a dados teóricos, simulando dez sensores com diferentes valores de constante de tempo, resultando em um erro médio de aproximadamente 0,74 %. Dados experimentais de 3 diferentes RTDs foram usados para estimar a constante de tempo, resultando em um erro máximo de 3,34 %. Os valores de constante de tempo estimados pelas RNAs foram comparados com aqueles obtidos pelo método tradicional, obtendo-se um erro médio de 18 % o que mostra que as RNAs são capazes de estimar a constante de tempo de uma forma precisa. / In a PWR nuclear power plant, the primary coolant temperature and feedwater temperature are measured using RTDs (Resistance Temperature Detectors). These RTDs typically feed the plants control and safety systems and must, therefore, be very accurate and have good dynamic performance. The response time of RTDs is characterized by a single parameter called the Plunge Time Constant defined as the time it takes the sensor output to achieve 63.2 percent of its final value after a step change in temperature. Nuclear reactor service conditions are difficult to reproduce in the laboratory, and an in-situ test method called LCSR (Loop Current Step Response) test was developed to measure remotely the response time of RTDs. From this test, the time constant of the sensor is identified by means of the LCSR transformation that involves the dynamic response modal time constants determination using a nodal heat-transfer model. This calculation is not simple and requires specialized personnel. For this reason an Artificial Neural Network has been developed to predict the time constant of RTD from LCSR test transient. It eliminates the transformations involved in the LCSR application. A series of LCSR tests on RTDs generates the response transients of the sensors, the input data of the networks. Plunge tests are used to determine the time constants of the RTDs, the desired output of the ANN, trained using these sets of input/output data. This methodology was firstly applied to theoretical data simulating 10 RTDs with different time constant values, resulting in an average error of about 0.74 %. Experimental data from three different RTDs was used to predict time constant resulting in a maximum error of 3,34 %. The time constants values predicted from ANN were compared with those obtained from traditional way resulting in an average error of about 18 % and that shows the network is able to predict accurately the sensor time constant.

En el presente proyecto de la bebida Mood-On, que está hecha a base de papas y frutos exóticos, se muestra su sostenibilidad a través de los distintos análisis realizados en Lima Metropolitana. Asimismo, este producto va dirigido hacia los sectores socioeconómicos A, B, C y que se encuentren en el rango de edad de 18 a 24 años. Del mismo modo, podemos indicar que, si bien hay una presencia consistente de bebidas RTD en el mercado peruano, los consumidores no se identifican con los productos ya establecidos. Por consiguiente, podemos mencionar que el mercado limeño tiene una necesidad que no ha sido satisfecha; ya sea por falta de sabores u otro factor clave. En adición a esto, para la realización del trabajo, se desarrollaron entrevistas a los usuarios para ratificar el nivel de aceptación del producto, a su vez, se hizo contacto con las licorerías a través de medios tradicionales y no tradicionales para la estimación de las ventas. Asimismo, se contactó con un ingeniero de alimentos para la elaboración de la receta, puesto que se ha tenido que considerar diferentes aspectos con respecto a la bebida RTD. Finalmente, se ha requerido para la inversión un total de S/27,261.72 para que se puedan iniciar las actividades de producción y la utilidad neta que se generará en el primer año es de39,186.95 nuevos soles, 60,913.85 nuevos soles en el segundo año y para el tercer año ascendería a 613,802.47 nuevos soles. / In the present project of the Mood-On drink, which is made from potatoes and exotic fruits, its sustainability is shown through the different analyzes carried out in Metropolitan Lima. Likewise, this product is aimed at socioeconomic sectors A, B, C, and that are in the age range of 18 to 24 years. Similarly, we can indicate that although there is a consistent presence of RTD beverages in the Peruvian market, consumers do not identify with the already established products. Therefore, we can mention that the Lima market has a need that has not been met; either for lack of flavors or another key factor. In addition to this, to carry out the work, interviews were carried out with users to ratify the level of acceptance of the product, in turn, contact was made with the liquor stores through traditional and non-traditional means for estimating sales. Likewise, a food engineer was contracted to prepare the recipe, since different aspects of the RTD drink had to be considered. Finally, a total of S /. 27,261.72 so that production activities can begin and the net profit that will be generated in the first year is –S/39,186.95, S/60,913.85 in the second year and for the third year it would amount to S/613,802.47 / Trabajo de investigación

This master‘s thesis deals with temperature measurement in industrial environment. The first part of this thesis is aimed at studing basic principles of temperature measurement using resistive temperature detectors. Next parts describe design and practical implementation of inteligent temperature transmitter with digital output RS485. This incudes detailed design of circuit solution, printed circuit board, firmware for used microcontroller and user‘s software for personal computer. The second part studies basics of the comunication standard Ethernet (IEEE 802.3), it discusses nowadays possibilities of Ehternet implementation to industrial trasmitters. Last parts of the thesis are aimed at design and practical realization of Ethernet communication module.

The resonant tunneling diode (RTD) is the fastest electron device to-date in terms of its ability to generate continuous-wave terahertz frequency at room temperature, owing to its unique characteristic of negative differential resistance (NDR). In this work, a lattice-matched In0.53Ga0.47As (on InP) is used as the cladding layer, while a highly-compressive strained In0.8Ga0.2As is sandwiched between two tensile-strained pseudomorphic AlAs barriers to form the active double barrier quantum well RTD structure grown by Molecular Beam Epitaxy. The ultimate aim of this work was to integrate an optimised RTD into an oscillator circuit to enable a 100 GHz (W-band) MMIC RTD oscillator. One of the key challenges in this work was to improve the DC performance of the RTD, through extensive material and structural characterisations. Growing nano-scale epitaxial layers require a high degree of controllability with mono-layer precision. The dependencies of the NDR components, such as the peak current density, peak voltage and peak-to-valley current ratio (PVCR) towards variations in structural thickness were studied systematically. Through this work, it is found that the peak current density is strongly affected by monolayer variation in barrier thickness. The effect of quantum well thickness variation towards peak current density is relatively weaker. Interestingly, variation in spacer layer thickness has very little influence towards the magnitude of the peak current density. The fabrication of the RTD using a conventional i-line optical lithography created its own challenge. The process capability to reduce mesa active area down to sub-micrometer level to reduce device’s geometrical capacitance for high frequency, THz applications has been made feasible in this work. The conventional i-line optical lithography was combined with a newly developed tri-layer soft reflow technique using solvent vapour resulted in sub-micrometer RTDs. The DC characterisation of the fabricated RTDs showed excellent device scalability, indicating a robust processing. This novel sub-micron processing technique with high throughput and repeatability is a very promising low cost technique. A collaborative effort between the University of Manchester and Glasgow paved the way towards the realisation of an integrated W-band RTD MMIC oscillator. The circuit-combining topology was designed by the High Frequency Electronics Group in Glasgow while the mask-layout and oscillator fabrication took place in Manchester. An active RTD from sample XMBE#301 with peak current density of 1.4 x 105 A/cm2 and PVCR of 4.5 was integrated into a 100 GHz MMIC oscillator to successfully produce a measured frequency of 109 GHz with an un-optimised 5.5 μW output power at room temperature (mesa area = 4x4 μm2).

This diploma thesis describes design and development of creating field instrument demonstration kit. Kit is capable of measuring multiple sensors such as thermocouples, RTDs, or pressure sensors, analogue sensor simulation is also provided. Sensor’s side is isolated from output, which is composed of 4 - 20 mA current loop and HART interface. Current loop also provides power supply and kit can communicate via HART also when alarm current (3,2 mA) is set. Basic safety features like open wire detection, over and undervoltage protection are also implemented.