International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This article presents a measurement system based on the RS-485 interface. The presented system is an alternative solution for distributed measurement systems, which cannot be built using IEEE-488 interface due to distance limitation between elements of the system. The RS-485 interface is a base for communication between measurement instruments and uses a Master-Slave protocol to exchange data between them. One dedicated master device, usually a PC, controls all slave devices connected to the interface. To control measurement devices SCPI language is used. This solution simplifies communication between measurement devices and allows utilizing the HP-VEE environment to control any SCPI devices connected to the RS-485 network.

This thesis investigates omnidirectional and directional ultra wideband (UWB) antennas for communication and microwave imaging applications. To reduce interference with existing technologies, monopole antennas with efficient band-stop functions are introduced. Single and double slots acting as series resonators are used. Reduction in the antenna gain in the stop-band regions of about 19.5 dB is achieved. Central metal removal and ground plane size effects on the antenna performance are investigated. To eliminate signal distortion caused by such monopole antennas, phase centre behaviour over the entire frequency band of operation is investigated at different principle planes, which have not been done before. This study will also show how these antennas act in different communication scenarios and where the radiation will be coming from at different frequencies. The effect of including different slots with different shapes on the performance of phase centre of these antennas is also investigated. Different methods to minimize the antenna phase centre movement are studied. Novel microstrip antennas with UWB impedance and radiation pattern bandwidth and low cross polarization components are introduced to work over the frequency band from 3 to 20 GHz. The antennas introduced are double-layer structures in which the radiator is sandwiched between two identical partial ground planes or a partial ground plane is sandwiched between two radiators. Results show a significant reduction in the cross polarization components at all frequencies. A novel high gain UWB Vee dipole antenna with a UWB coaxial balun feed is introduced to cover the existing and future UWB communication applications. Different type of loadings such as a reflecting ground below the antenna, a dielectric sleeve over the UWB balun and conical dielectrics between the Vee plates are also used and studied that show enhanced gains and lower sidelobes. A miniaturized-type UWB Vee dipole antenna is also investigated for microwave imaging applications. The antenna has a small radiation aperture which makes it a good candidate for array type applications. Full wave analysis of studied antennas are done using Ansoft HFSS, finite-element-methods based software. Experimental investigations are done to confirm the accuracy of simulated results.

This thesis investigates omnidirectional and directional ultra wideband (UWB) antennas for communication and microwave imaging applications. To reduce interference with existing technologies, monopole antennas with efficient band-stop functions are introduced. Single and double slots acting as series resonators are used. Reduction in the antenna gain in the stop-band regions of about 19.5 dB is achieved. Central metal removal and ground plane size effects on the antenna performance are investigated. To eliminate signal distortion caused by such monopole antennas, phase centre behaviour over the entire frequency band of operation is investigated at different principle planes, which have not been done before. This study will also show how these antennas act in different communication scenarios and where the radiation will be coming from at different frequencies. The effect of including different slots with different shapes on the performance of phase centre of these antennas is also investigated. Different methods to minimize the antenna phase centre movement are studied. Novel microstrip antennas with UWB impedance and radiation pattern bandwidth and low cross polarization components are introduced to work over the frequency band from 3 to 20 GHz. The antennas introduced are double-layer structures in which the radiator is sandwiched between two identical partial ground planes or a partial ground plane is sandwiched between two radiators. Results show a significant reduction in the cross polarization components at all frequencies. A novel high gain UWB Vee dipole antenna with a UWB coaxial balun feed is introduced to cover the existing and future UWB communication applications. Different type of loadings such as a reflecting ground below the antenna, a dielectric sleeve over the UWB balun and conical dielectrics between the Vee plates are also used and studied that show enhanced gains and lower sidelobes. A miniaturized-type UWB Vee dipole antenna is also investigated for microwave imaging applications. The antenna has a small radiation aperture which makes it a good candidate for array type applications. Full wave analysis of studied antennas are done using Ansoft HFSS, finite-element-methods based software. Experimental investigations are done to confirm the accuracy of simulated results.

Neste trabalho apresentamos uma investigação desenvolvida ao longo de três anos em cursos introdutórios de Física da Universidade Federal do Rio Grande. O objetivo foi minimizar a dicotomia observada entre teoria e laboratório. A estratégia de ensino utilizada nas disciplinas de Física Geral para Engenharia fez uso do Vê de Gowin, um dispositivo heurístico capaz de explicitar como se dá o processo de produção do conhecimento científico. A construção de diagramas Vê foi utilizada para auxiliar na compreensão de textos nas aulas teóricas e como alternativa aos tradicionais relatórios nas aulas experimentais. A professora também fez uso dos Vês para organizar o ensino, em especial das aulas de laboratório. Alicerçados na teoria da aprendizagem significativa de Ausubel e Novak e nas teorias de ensino de Gowin e Moreira, e fundamentados em algumas idéias-chave de epistemólogos e filósofos da ciência contemporâneos, procuramos estimular uma integração entre teoria e experimentação, buscando contribuir para uma compreensão mais efetiva dos conceitos físicos e das concepções epistemológicas veiculadas nas aulas de Física. Na pesquisa, optamos por uma metodologia interpretativa, de imersão, mas também fizemos uso de vários dados quantitativos, procurando indícios da validade da estratégia. Os resultados mostraram que a eficácia do instrumento, para promover a desejada integração, depende da atuação decidida do professor. Indicaram também que as concepções dos estudantes sobre a ciência, o cientista e o modo como se dá a construção do conhecimento, ensinadas muitas vezes de forma implícita em aula, são persistentes e capazes de interferir na aprendizagem de teorias físicas. / In this paper, we presents a research carried out over three years in Physics introductory courses at Federal University of Rio Grande. The aim of the present study was to minimize the observed dichotomy between theory and lab. The teaching strategy in General Physics disciplines for Engineering has made use of Gowin's Vee, a heuristic device able to explain the process of scientific knowledge production. The construction of Vee diagrams was used to assist understanding of texts in theory classes and as an alternative to traditional reports in the experimental classes. The teacher also made use of it to organize the education, especially for laboratory classes. We based our work on the theory of Ausubel and Novak's meaningful learning and on Gowin and Moreira's theories of teaching and we also grounded it on some key ideas of contemporary epistemology and philosophy of science. We want to promote theory-experiment integration, seeking to contribute to a more effective comprehension of physical concepts and epistemological conceptions expressed in Physics classes. In research, we opted for an interpretative methodology, but we also made use of several quantitative data, looking for evidence of strategy's validity. The results showed that the effectiveness of the instrument performance to promote the desired integration depends on the teacher's decisive role. They also indicated that the students conceptions about science, the scientist and how the knowledge construction is made, that are taught many times implicitly in class, are persistent and can interfere in the physical theories learning.

Neste trabalho apresentamos uma investigação desenvolvida ao longo de três anos em cursos introdutórios de Física da Universidade Federal do Rio Grande. O objetivo foi minimizar a dicotomia observada entre teoria e laboratório. A estratégia de ensino utilizada nas disciplinas de Física Geral para Engenharia fez uso do Vê de Gowin, um dispositivo heurístico capaz de explicitar como se dá o processo de produção do conhecimento científico. A construção de diagramas Vê foi utilizada para auxiliar na compreensão de textos nas aulas teóricas e como alternativa aos tradicionais relatórios nas aulas experimentais. A professora também fez uso dos Vês para organizar o ensino, em especial das aulas de laboratório. Alicerçados na teoria da aprendizagem significativa de Ausubel e Novak e nas teorias de ensino de Gowin e Moreira, e fundamentados em algumas idéias-chave de epistemólogos e filósofos da ciência contemporâneos, procuramos estimular uma integração entre teoria e experimentação, buscando contribuir para uma compreensão mais efetiva dos conceitos físicos e das concepções epistemológicas veiculadas nas aulas de Física. Na pesquisa, optamos por uma metodologia interpretativa, de imersão, mas também fizemos uso de vários dados quantitativos, procurando indícios da validade da estratégia. Os resultados mostraram que a eficácia do instrumento, para promover a desejada integração, depende da atuação decidida do professor. Indicaram também que as concepções dos estudantes sobre a ciência, o cientista e o modo como se dá a construção do conhecimento, ensinadas muitas vezes de forma implícita em aula, são persistentes e capazes de interferir na aprendizagem de teorias físicas. / In this paper, we presents a research carried out over three years in Physics introductory courses at Federal University of Rio Grande. The aim of the present study was to minimize the observed dichotomy between theory and lab. The teaching strategy in General Physics disciplines for Engineering has made use of Gowin's Vee, a heuristic device able to explain the process of scientific knowledge production. The construction of Vee diagrams was used to assist understanding of texts in theory classes and as an alternative to traditional reports in the experimental classes. The teacher also made use of it to organize the education, especially for laboratory classes. We based our work on the theory of Ausubel and Novak's meaningful learning and on Gowin and Moreira's theories of teaching and we also grounded it on some key ideas of contemporary epistemology and philosophy of science. We want to promote theory-experiment integration, seeking to contribute to a more effective comprehension of physical concepts and epistemological conceptions expressed in Physics classes. In research, we opted for an interpretative methodology, but we also made use of several quantitative data, looking for evidence of strategy's validity. The results showed that the effectiveness of the instrument performance to promote the desired integration depends on the teacher's decisive role. They also indicated that the students conceptions about science, the scientist and how the knowledge construction is made, that are taught many times implicitly in class, are persistent and can interfere in the physical theories learning.

Neste trabalho apresentamos uma investigação desenvolvida ao longo de três anos em cursos introdutórios de Física da Universidade Federal do Rio Grande. O objetivo foi minimizar a dicotomia observada entre teoria e laboratório. A estratégia de ensino utilizada nas disciplinas de Física Geral para Engenharia fez uso do Vê de Gowin, um dispositivo heurístico capaz de explicitar como se dá o processo de produção do conhecimento científico. A construção de diagramas Vê foi utilizada para auxiliar na compreensão de textos nas aulas teóricas e como alternativa aos tradicionais relatórios nas aulas experimentais. A professora também fez uso dos Vês para organizar o ensino, em especial das aulas de laboratório. Alicerçados na teoria da aprendizagem significativa de Ausubel e Novak e nas teorias de ensino de Gowin e Moreira, e fundamentados em algumas idéias-chave de epistemólogos e filósofos da ciência contemporâneos, procuramos estimular uma integração entre teoria e experimentação, buscando contribuir para uma compreensão mais efetiva dos conceitos físicos e das concepções epistemológicas veiculadas nas aulas de Física. Na pesquisa, optamos por uma metodologia interpretativa, de imersão, mas também fizemos uso de vários dados quantitativos, procurando indícios da validade da estratégia. Os resultados mostraram que a eficácia do instrumento, para promover a desejada integração, depende da atuação decidida do professor. Indicaram também que as concepções dos estudantes sobre a ciência, o cientista e o modo como se dá a construção do conhecimento, ensinadas muitas vezes de forma implícita em aula, são persistentes e capazes de interferir na aprendizagem de teorias físicas. / In this paper, we presents a research carried out over three years in Physics introductory courses at Federal University of Rio Grande. The aim of the present study was to minimize the observed dichotomy between theory and lab. The teaching strategy in General Physics disciplines for Engineering has made use of Gowin's Vee, a heuristic device able to explain the process of scientific knowledge production. The construction of Vee diagrams was used to assist understanding of texts in theory classes and as an alternative to traditional reports in the experimental classes. The teacher also made use of it to organize the education, especially for laboratory classes. We based our work on the theory of Ausubel and Novak's meaningful learning and on Gowin and Moreira's theories of teaching and we also grounded it on some key ideas of contemporary epistemology and philosophy of science. We want to promote theory-experiment integration, seeking to contribute to a more effective comprehension of physical concepts and epistemological conceptions expressed in Physics classes. In research, we opted for an interpretative methodology, but we also made use of several quantitative data, looking for evidence of strategy's validity. The results showed that the effectiveness of the instrument performance to promote the desired integration depends on the teacher's decisive role. They also indicated that the students conceptions about science, the scientist and how the knowledge construction is made, that are taught many times implicitly in class, are persistent and can interfere in the physical theories learning.

The lead-acid batteries are the most commonly used electrochemical power sources and are the oldest type of secondary battery cells. This master thesis provides a short introduction to the lead-acid batteries. It shows possible ways of sorting from different points of view, describes construction of lead-acid batteries, parameters of lead-acid batteries and electrochemical and physical reactions inside the battery. Futher the thesis deals with pulse charging of lead-acid batteries. The thesis describes the production of a set of experimental electrodes for electrochemical workplace resources. The thesis introduces the develepment environment Agilent VEE PRO and demonstrates its capabilities. The final part of this thesis are experiments focusing on the pulse charging using negative current pulses and evaluate the effect of different pulse modes on cells.

The thesis deals with the ultrasonic velocity measurement. The ultrasonic velocity was determined on basis of ultrasonic flight time from a transmitter to a receiver. Three methods how to determine the ultrasonic velocity in medium were proposed. Special algorithms have been created and later on build in the developed program. All the software was developed in Agilent VEE Pro 8.5. The thesis contains a proposal of two experiments tutorials for the department of Biomedical engineering that will be used during experimental lessons. The experiments deal with ultrasonic velocity measurement.

The aim of this work is to design a communication module for laboratory source Manson. This power supply communicates only through a serial RS-232 link. Modern computers usually use for the connection with other peripherals mainly USB. Designed communication module contains converter between the RS-232 and USB. Power supply is used in the automated measurement setup, which is controlled from the Virtual Engineering Environment from the Agilent Technologies. Direct commands for laboratory source Manson are not compatible with the SCPI (Standard Commands for Programmable Instruments) standard commands. So, the communication module converts commands from the SCPI format to Manson supply instructions. The communication with the Manson supply will be obvious for students by using new communication module.

The purpose of the diploma thesis is to design a manufacturing technology of the Brake Disk. The component is made of stainless steel 17 023 (X30Cr13). The blank is 2 mm thick sheet metal. Within the literary study the comparison of the possible technologies of manufacturing has been carried out. With respect to the batch size 200 000 pieces the fineblanking technology has been chosen. For the manufacturing has been chosen HFA 700 press. The major point of diploma thesis is to design a cutting tool and create a drawing documentation. The part of the project is the technical and economical evaluation of the designed manufacturing process.