http://repositorio.jesuita.org.br/handle/UNISINOS/1689 PPG Engenharia Elétrica Tue, 14 Apr 2026 21:09:44 GMT 2026-04-14T21:09:44Z http://repositorio.jesuita.org.br/handle/UNISINOS/13986 Microfabrication of electrode-integrated liver-on-achip for in-vitro cell culture monitoring Dalló, Luíse Cambruzzi The liver is a vital organ responsible for crucial metabolic functions, drug metabolism, detoxification, and the production of proteins necessary for maintaining homeostasis in the body. However, studying liver physiology and drug metabolism has traditionally relied on animal models and two-dimensional (2D) cell cultures, which often fail to recapitulate the complex and dynamic nature accurately. Liver-on-a-chip is an emerging technology that aims to replicate the structure and functions of the human liver in a miniature and controlled in vitro platform. This study presents the fabrication and characterization of a liver-on-a-chip microfluidic device integrating microelectrodes for real-time cell culture monitoring. The device mimics the hepatic microenvironment by incorporating microchannels connected through endothelial-like capillaries, facilitating controlled nutrient exchange and waste removal under continuous perfusion conditions. The fabrication process involved three main stages: electrode fabrication, mold fabrication, and microchannel manufacturing. HepG2 cells were cultured within the microfluidic device under dynamic perfusion, demonstrating progressive adhesion, proliferation, and viability over multiple days. Impedance spectroscopy was employed to quantitatively assess cell behavior, with measurements indicating stable electrode performance and reliable monitoring of cellular dynamics. The results confirmed that the liver-on-a-chip device successfully supports long-term cell culture while providing real-time electrical characterization. This makes it a promising platform for hepatic disease modeling and pharmaceutical testing. Fri, 04 Apr 2025 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/13986 2025-04-04T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/13914 Método para simulação e análise de VTCDs em instalações elétricas industriais Ayres, Ingridt Cezar This work presents a simplified methodology for the analysis of Short-Duration Voltage Variations (SDVV) in Group A consumer units, with an emphasis on industrial facilities composed of motor loads. The proposal is based on the modeling of inrush current profiles of three-phase induction motors, obtained experimentally and incorporated into the OpenDSS simulation environment through LoadShape curves. The approach considers the technical criteria established in Module 8 of PRODIST, with the proposal to include a new severity region representing the ideal operating range. To evaluate the methodology, simulated scenarios were developed with different electrical configurations, and the voltage disturbances were quantified using the Impact Factor (FI) and the Base Impact Factor (FIBASE) indicators. The results obtained demonstrate the applicability of the methodology for preventive analysis of SDVVs, enabling technical diagnostics in the design or operation phase of the plant and contributing to compliance with the regulatory limits for electric power quality. Tue, 17 Jun 2025 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/13914 2025-06-17T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/13913 Metodologia para determinação da capacidade de hospedagem de sistemas fotovoltaicos para consumidor livre Souza, Deivis Marques de The addition of Photovoltaic Systems (PS) to the internal networks of consumers inserted in the Free Contracting Environment (FCE), called free consumers, brings with it a set of challenges related to the planning and integration of such systems. Among these challenges, the present work aims to propose a methodology capable of determining the Hosting Capacity (HC) of PS for free consumers of the self-producer type, without injecting surplus energy produced into the distributor's network, without exceeding limits of predefined technical parameters such as overvoltage (V), overcurrent (I) and reverse power flow (RPF), and obtaining results with low data processing times, through the use of Visual Basic for Application (VBA) and OpenDSS tools. Currently, there are numerous works containing PS of HC analysis methods aimed at distribution networks, and not for private networks of free consumers; and there is a strong trend of increasing the number of consumers migrating from the captive to the free market, due to the lower cost of electricity and the recent changes in the legislation of the sector. The presented method proposes four steps, including activity planning, field survey, modeling of the existing network and determination of the HC; for the latter two, a tool was developed in VBA, called CHSFV Interface, which uses OpenDSS as a tool for calculating power flow. This tool optimizes network modeling time, automates the HC and eliminates the need for indepth knowledge of the OpenDSS programming syntax by the user. The methodology was applied through a case study, based on a theoretical circuit model and contemplating four scenarios, which simulated the insertion of PS in different buses of the circuit, including the possibility of using an energy storage system. The results indicated that the methodology proved to be effective, presenting HC values appropriate to the type of technical parameter responsible for the limitation of each scenario; it was also possible to verify that the parameter V is not applicable to the proposed method, since it did not act in any of the scenarios. Fri, 30 May 2025 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/13913 2025-05-30T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/13213 Análise de projetos de encapsulamentos do tipo System-In-Package aplicando fluidodinâmica computacional (CFD) no processo de moldagem por compressão Padão, Felipe Schver Integrated circuits of the System-In-Package (SiP) type typically exhibit high component density in their construction, which may pose challenges in the integrated circuit encapsulation process. The aim of this study was to develop a computational model to simulate the compression molding process, with the purpose of validating SiP encapsulation designs, specifically in hard-to-reach regions such as the 16 Land Grid Array (LGA) device area, which was the focus of this study. This work aimed to improve the flow of the molding compound, also known as Epoxy Molding Compound (EMC), reducing the incidence of voids, a defect formed after molding where air becomes trapped in a specific region of the chip, potentially causing various quality issues such as short circuits, electrical defects, component delamination, and more. The methodology involved the study of different designs, with "A" and "B" being pre-existing SiP device designs, along with proposed designs "C" and "D" specifically for this study. These alternatives aimed to enhance the EMC flow. The main difference between designs is essentially the internal design of the integrated circuit, where the central terminal, responsible for heat dissipation, was modified. Existing samples underwent acoustic microscopy analysis, cross-sectional cutting, and statistical analysis. Designs "A" and "B," along with designs "C" and "D," were evaluated through numerical simulations using the COMSOL Multiphysics® program. Each design involved a change in the channel layout, aiming to improve the EMC flow. Design "A" lacked a proper entry area for EMC, and its channel construction hindered flow. On the other hand, the other designs provided an extra entry area for EMC, and their channels were reconfigured for improved fluidity, each with its own characteristics. Results showed that design "B" exhibited significant improvements compared to design "A," used as a reference. Design "B" demonstrated a 19.28% improvement in mass flow (fluidity), resulting in a substantial reduction in void formation, an undesirable flaw in semiconductor encapsulation processes. Designs "C" and "D," developed as alternatives to designs "A" and "B," showed simulation improvements compared to design "A" but not as much as the results obtained with "B." Design "C" had a 6.06% increase in mass flow, while design "D" showed a 16.80% increase compared to design "A." This approach provided insights to enhance designs subjected to the compression molding process, highlighting that design "B" is the alternative with the best channel flow and consequently has a lower probability of void formation. Tue, 31 Oct 2023 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/13213 2023-10-31T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/12825 Metodologia para avaliação da eficiência do indicador de DEC Programado no sistema de distribuição de energia elétrica Saldanha, Taric Magalhães The economic, social, and sustainable development of any region in the world relies on having sufficient and reliable energy at an appropriate price for the local reality. In this context, the distribution of electric power plays a key role and should ensure fair prices, service quality, and the quality of the supplied energy. In this regard, service provision can be evaluated through the analysis of indicators that demonstrate the evolution of the results themselves, the comparison with established regulatory targets or benchmarks, or even the comparative mode with companies in the same production sector, region, size, or other specific characteristic that is desired to be compared. For the electric power distribution model, in which regulatory bodies establish increasingly higher quality standards each year, investment in network improvement is crucial to be carried out with greater efficiency. In other words, the works must be the best possible and their execution should cause minimal impact on technical indicators and customer perception. In a scenario of constant need for investments in the distribution network, the optimization of the scheduled interruption component becomes a fundamental factor in determining the maximum investment with the lowest impact, so that the overall indicator perceived by the customer follows a downward trajectory over time. This study develops a methodology for analyzing and defining the attributes that each electric power distribution system has specifically and how each business unit is impacted by local characteristics in relation to the efficiency of the Planned Energy Interruption Duration (DEC Programmed) indicator during the process of executing works for system improvement, expansion, and maintenance. The application and utilization of a consistent database allow the model to provide reliability in its application and usage. Thus, the work proposes an evaluation methodology and the construction of a performance ranking that can be used in other electric power distribution companies, contributing to new studies and assessments of the efficiency of each company while respecting their specific characteristics and attributes of each operation. Mon, 24 Apr 2023 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/12825 2023-04-24T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/12638 Desenvolvimento de scaffolds condutivos de PLA e PVA com PEDOT para engenharia de tecidos Rodrigues, Tayná Copes In the area of regenerative medicine, multidisciplinary knowledge has been applied to build functional tissues and organs, aiming to prolong the quality and duration of life. One of the methods used for the development of these tissues is the incorporation of cells in scaffolds. The scaffold material must be biodegradable and bioabsorbable, in addition to having electrical conductivity to improve cell-to-cell communication. Thus, among the main materials used for the development of scaffolds, biodegradable polymers such as poly (lactic acid) PLA, poly (vinyl alcohol) PVA, alginate and conductive polymers such as PEDOT:PSS. The aim of this study was the development of scaffolds with conductive characteristics based on PLA or PVA and PEDOT as conductive element. For this, the chemical synthesis of the PEDOT:PSS was first performed, evaluating the method of obtaining and characteristics obtained, in addition to the possibility of substituting PSS for alginate. Subsequently, PEDOT:PSS was added to PLA and PVA with glycerol solutions. Then, scaffolds were produced through the method of molding with five different compositions of PLA, PVA and PEDOT:PSS. The scaffolds were characterized by Fourier transform infrared spectrometry, differential scanning calorimetry, thermogravimetric analysis, compression test, resistivity measurement by the four-point method, water absorption capacity, degradation assay and, cell viability. It was not possible to substitute PSS for alginate using the same methodology. Thermally stable scaffolds were produced, with porosity in the range of 75 – 96%, with appropriate rigidity for different types of human tissues, and with water absorption capacity ranging from 567% for scaffolds based on PVA and PEDOT:PSS at 26.5% for PLA with 10% PEDOT:PSS. The PVA scaffolds with PEDOT:PSS showed a conductivity of 8.9 x 10-4 ± 6.6 x 10-4 S/cm, and the PLA scaffolds 2.7 x 10-6 ± 9.7 x 10-6 S/cm for 10% PEDOT:PSS, sufficient to encourage cell proliferation and differentiation. PLA scaffolds with 10% PEDOT:PSS did not show cytotoxicity when compared to conventional 2D culture in plates, while the others scaffolds tested showed lower cell viability. Thus, the 10% PLA scaffold is most suitable for tissue engineering applications. Mon, 17 Apr 2023 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/12638 2023-04-17T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/12180 PCR: um modelo híbrido para previsão de grandezas elétricas aplicado em estudo de caso de um regulador de tensão em operação Costa, Ricardo dos Santos The growing demand for electricity and requirements imposed by regulatory agencies have led the conventional electricity distribution system to evolve into the context of smart grids. Data acquisition and analysis are central issues for the evolution of the distribution system. Machine learning technologies are gaining ground in applied studies, making this an emerging topic. The related studies do not address the preparation and analysis of data before application in artificial intelligence models. In this context, this work presents a model capable of performing the pre-processing, classification, and prediction of electrical quantities. Compared with related works, there is an indication that this is the first study that addresses the pre-processing and grouping of data by similarity to increase the effectiveness of artificial intelligence models. The Fuzzy C-Means method for data classification allows outliers to be found more assertively. The Grubbs method identifies critical operating points of the system. The regression stage presents predictions made with LSTM neural networks up to fourtime steps ahead with a percentage absolute average error of 0.16% using a real database of an electric power distribution utility. Wed, 05 Oct 2022 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/12180 2022-10-05T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/12179 Sistema não invasivo de monitoramento de baterias VRLA por método rápido de espectroscopia de impedância Silveira, Gabriel do Nascimento Many electrical and electronic devices use batteries as a source of energy, either as the main power supply or emergency supply. Among the different characteristics and construction materials, the Valve Regulated Lead Acid batteries are widely used in uninterruptible power supplies (UPS). This equipment has high applicability in highly critical machines, in order to provide contingency energy from batteries in eventual power outages from the primary source. Consequently, it is necessary constant monitoring of the batteries used and, in this sense, the development of Battery Monitoring Systems (BMS) is increasing. The purpose of this work was to develop an embedded system capable of collecting data for the diagnosis of the health status of VRLA batteries. Using a hardware topology applied to active harmonic correction filters, thus implementing a system capable of performing impedance spectroscopy on the batteries without desconnected them from the UPS. Successfully providing impedance parameters for future battery health state estimation systems. Fri, 23 Sep 2022 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/12179 2022-09-23T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/11857 Desenvolvimento de receptor de wake-up de tempo discreto para CMOS 180nm Ferreira, Fernando This work proposes a discrete-time (DT) wake-up receiver (WUR) as a solution to reduce the power consumption of Internet of Things (IoT) devices. The core of the proposed circuit is the discrete-time mixer, formed by a switched capacitors structure, that translates and filters the on-off keying (OOK) modulation radiofrequency (RF) signal. Other blocks that compose the circuit are: an integrated matching network, frequency dividers, a baseband amplifier and a voltage reference. This research conduct the design and sizing of the components, simulates the circuit and executes the tape-out of the receiver in TSMC180NM technology. The extracted layout simulations indicate a sensitivity of -52 dBm and a consumed power of 29.33 µW, with the circuit being operated at 900 MHz, with 100 kbps and 1.2 V. The research also measured the manufactured chip on its peak performance operation point, at 1.15 GHz with 50 kbps and 1.1 V, the receiver presents a sensitivity of -17 dBm and a consumed power of 46.3 µW. It is postulated that the chip’s poor result is due to an insufficient gain of the baseband amplifier. Improvements were implemented to the circuit on a second TSMC180NM tape-out, which until the moment this work had been written has not yet been delivered. For this second chip, the extracted layout simulation shows a sensitivity of -70 dBm and power consumption of 33.3 µW. The present work brought important contributions to this line of research as it validates, through measurements on the chip, the proof of concept of the use of discrete-time receivers as wake-up receivers Fri, 25 Mar 2022 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/11857 2022-03-25T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/11856 Avaliação da assertividade de projetistas em relação à previsão do impacto dos desligamentos Boff, Diogo Slovinscki The energy distributors’ concession contracts require, among other obligations, the maintenance of supply quality levels as well as their continuity. For this, companies need to constantly maintain and expand the system so that it meets the stipulated goals. In the state of Rio Grande do Sul, the electrical distribution network has approximately 40% of wooden poles and also several municipalities and a load center with only one power supply. There are also areas in constant economic expansion that have high energy demand. Given this scenario, distributors need to annually invest in the system through works. These, in turn, demand a large amount of material, in addition to scheduled shutdowns that hurt the same indicators that need to be improved. This difficult balance requires a good project and planning of works. This work will have its scope in the impact that the Project Technician has on the works and on the continuity indicators. In the design stage, it will be analyzed whether a particular work is viable from the point of view of quality and continuity indicators. Through the creation of a modeling tool for the project technician, the impact of scheduled shutdowns and the shutdown itself, in the execution of the work, will be foreseen. The human factor is currently decisive for the good planning of the works. In this way, this tool seeks to model the performance of the project technician and its influence on the correct planning of works. It is intended to assess whether the technicians are at a satisfactory nlevel according to their experience and difficulty of activities. The Project Technician’s modeling was done using the SVM and Neural Networks algorithms. Being the SVM the one that brought the best result with 54% of accuracy. This value represents a gain of 9% in relation to the current results. As this is a pioneering project, this work opens the way for further exploration of the topic, with the incorporation of new variables, it is estimated that an accuracy of up to 20%. Thu, 30 Jun 2022 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/11856 2022-06-30T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/11810 Síntese de solução coloidal de nanopartículas de ouro para aplicação em dispositivos de detecção de biomarcadores Moraes, Duane da Silva The gold nanoparticles (GNPs) have become strong candidates for applications in biosensors, as they have high electrical conductivity and catalytic activity, corrosion resistance, biocompatibility, low cytotoxicity, high stability in biological fluids and easy functionalization. One of the most consolidated methodologies in the literature for the synthesis of GNPs is the chemical reduction of Au3+ ions in metallic gold through chemical reducing agents, and any change in the synthesis parameters, as well as the insertion of stabilizing reagents influence the shape and size of the nanoparticles. Considering the above, the objective of this work is to study the synthesis of gold nanoparticles, aiming its application in biosensors. The methodological process was divided into three stages: the first stage consists of the study of the most suitable reducing agent for the synthesis of GNPs, in which the agents Sodium Citrate and Sodium Borohydride were evaluated; in the second stage, other synthesis parameters were evaluated, such as stirring speed, reduction agent addition speed and molar ratio between the reducing agent and precursor; in the third step, the GNPs solution chosen as the promising synthesis was functionalized with Polyethyleneimine to activate its surface and enable the bioreceptor coupling. All syntheses performed showed the characteristic band of metallic gold between 500 and 550 nm in the UV-visible analysis, confirming the formation of gold nanoparticles. The colloidal solutions synthesized with Sodium Citrate showed more intense coloration, the experimental method is simpler and requires less reaction time, compared to GNPs produced with Sodium Borohydride. The characterization analyzes of the samples from the second stage revealed that the higher the stirring speed of the system, the greater the diffusion speed of the chemical species in solution and the smaller the size of the gold nanoparticles. Regarding the molar ratio between precursor and reducing reagents added to the synthesis, it can be concluded that there is an ideal molar ratio and that higher or lower concentrations of the reducing agent in the solution contribute to an increase in the size of GNPs. Finally, regarding the addition speed of the reducing agent in the reaction medium, it can be inferred that a slower addition causes the production of larger nanoparticles, with variability of sizes and agglomerates. The results of the third stage of the work presented the possibility of functionalizing the gold nanoparticles with Polyethyleneimine, which interacts with GNPs by Van der Waals forces. The electrochemical characterization of commercial electrodes modified with functionalized gold nanoparticles revealed a significant reduction in charge transfer resistance when compared to the unmodified device, due to the conductive capacity of GNPs, contributing to the increased sensitivity of the electrodes in detecting chemical/biological reactions. Thus, it is concluded that it is possible to apply the solution of functionalized gold nanoparticles produced in this work in the construction of biosensors and that the next step of the study should focus on the bioreceptor coupling, which will depend, in turn, on the target biomarker for the diagnosis. Fri, 14 Jan 2022 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/11810 2022-01-14T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/11336 Desenvolvimento, implementação e estudo de caso de um software para detecção automática de falhas em motores elétricos de indução e sistemas mancalizados via análise de vibração e temperatura Piaia, Guilherme Angelo Faults in industrial equipment lead to production interruptions, losses and, consequently, loss of competitiveness with those that mitigate these problems. The development and implementation of solutions that seek to detect and identify faults in this equipment are, mostly indispensable to minimize production losses and potential risks to the health of people working in these environments. Present in these machines, the engines induction motors, which coupled in a bearing system, create the necessary movement to carry out the objective activity of the machine. These moving parts, with the use or with any adversity, at some point they will collapse, showing the fault, so it is necessary to monitor them in real time to predict and avoid them. The current state-of-the-art presents some works that consider the vibration energy in the spectrum, but the construction of a system that monitors in real time and can be used in several devices, no works were found in this sense. This work presents a solution that integrates software and hardware for solve the aforementioned problem, including in real time and that learns the behaviour equipment, suggesting regions of alert and danger, serving as a tool for taking decisions. For the development, the physical quantities of vibration were used, together with signal processing techniques and machine learning. After development and implementation, the solution was used in a case study in companies from different branches of industry, which obtained very positive results. The solution was able to store, process and make available the vibration and temperature data in real time, where the system detected in advance in one case, and not the other, despite the advanced state of wear of the equipment, according to an ISO 10816-1 standard, demonstrate that the equipment was in severe condition. Fri, 15 Oct 2021 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/11336 2021-10-15T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/10912 Development of microfluidic device for cell lysis Maraschin, Samuel Tavares da Silva The use of certain protocols to diagnose diseases requires specific tools and highly qualified professionals. This high-end scenario has leveraged the development of new mechanisms and processes on biomolecular analyses. In this context, recent discussions regarding new portable and low-cost devices which enable faster results have been receiving attention due to the possibility of speeding up physician decision making. The speed of decision-making has garnered attention even prior to the 2020 pandemic, and has proved to be an important factor in successful treatments. The process of disrupting cell membrane is known as cell lysis. This process is a fundamental step in several molecular analyses such as Polymerase Chain Reaction (PCR) standard analysis to diagnose diseases such as Sars CoV 2 (COVID-19) and many others. The standard protocol to perform PCR uses specific chemicals to rupture cell membrane, which increases the costs of tests. Since these materials are not currently available in the Brazilian market, it results in a long lead time. In addition, the protocols used to run PCR require specific training for staff, adding extra cost and time into the process. Therefore, this study presents the development of a microdevice for cell lysis. The proposed device was made using microfabrication techniques developed by the microelectronics industry. The microdevices have shown some advantages to conventional technologies such as portability, faster results, and a decrease of contamination risk when the samples are handled in a closed system. To prove the efficiency of the device, two analyses were performed: RNA concentration measured by a spectrophotometer and amplification of genetic material using PCR methodology. Based on results obtained through this technology, it was possible to establish the great prospective brought out by this method on health services reducing cost and speeding up results. A microdevice with 15 μm electrodes got promising results when compared to the ones from standard techniques. A significant time reduction on sample preparation, aside from portability and friendly user operation are some of benefits provide by the proposed device. Tue, 05 Oct 2021 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/10912 2021-10-05T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/10292 Projeto e análise de circuitos de coleta de energia de rádio frequência para aplicações IOT Martins, Renan Daniel Dias This work presents an overview of RF Energy Harvesting devices, pointing out the advantages and disadvantages of the main topologies used, as well as presenting the most relevant points for the design of Energy Harvesting systems. To demonstrate the operation of an Energy Harvesting system, a circuit is proposed for this purpose that makes use of an RF antenna, an impedance matching network with a resonant circuit for raising the input voltage and a modified gate cross-coupled charge pump rectifier (CC-CPR). The proposed circuit uses ten stages of CC-CPR to providing an output voltage equal to 1.2 V when powered with -26 dBm. Ways to define design parameters for EH are demonstrated, such as output voltage, number stages of rectification, alternative topologies, and how to find the optimal working point of the circuit through simulations. The integrated circuit was developed in CMOS TSMC 180nm technology and has a maximum power conversion efficiency (PCE) of 28.41%. Thu, 29 Jul 2021 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/10292 2021-07-29T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/10291 Desenvolvimento de uma antena impressa sub-GHz encapsulada com dimensões reduzidas Ribeiro, Maurício Carlotto Since the realization of the first effective communication between wireless devices, many technologies have emerged to fill the most variety of markets and opportunities, which has made the term “portable” increasingly frequent and necessary in product development. Over this road, antennas have always remained present as they are an essential part of the whole system that allows the transmission and reception of signals. However, the technologies employed in the antenna’s development did not follow the same evolution speed as the RF (Radio Frequency) circuits, which became increasingly reduced. Thus, printed antennas began to receive greater importance as it was possible to include them in the device without occupying a significantly large area. Nevertheless, it appears that the development of radios with integrated antennas represents a potentially viable proposal in the sense of providing a ready-made wireless communication structure in a single package. In this context, this work aims to develop a small, encapsulated antenna for Internet of Things products, focusing on technologies that uses sub-GHz frequencies. The proposal consists in overcoming the physical limitations through antenna miniaturization methodologies, in order to produce a printed antenna model that can be encapsulated with the circuit to which it belongs. The first work consisted in the evaluation of different antenna designs through electromagnetic simulations, which allowed establishing their electrical characteristics and choosing the one that presents the best possibility of being encapsulated and offering a good performance. Two miniaturization methodologies were chosen and tested separately through simulations: the use of substrates with high dielectric constant and the application of Fractal geometries. The simulation results showed that the replacement of common meanders by the Hilbert-type Fractal Geometry in an inverted F Antenna was able to obtain a reduction of up to 44.45% of the original dimensions, but with some punctual performance reductions. Prototypes were manufactured to evaluate the results obtained in software, however, the measurements showed inconsistency with values verified in simulation. Thus, it was necessary to adjust the characteristics of the prototypes through physical adjustments and the addition of matching networks, thus allowing the expected performance to be achieved and even improving some characteristics. Communication evaluations were conducted using manufactured antennas and test equipment, which endorse the conclusion that the miniaturization process allowed the development of small antennas, including manually encapsulated, which are capable of transmitting and receiving signals from RF successfully. Fri, 30 Jul 2021 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/10291 2021-07-30T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/10165 Estudo de sistema de medição de sinal de tensão sem contato e sem aterramento, em média tensão Vogel, Ederson Paulo The measurement of current and voltage (as well as the indexes derived from them) in the electricity distribution network becomes more and more necessary in the present day. The power concessionaires seek to distribute to their customers, reliability and stability in the supply of this energy with admissible levels of quality established by the regulatory body of the electric system. In order to carry out a study of a signal measurement system without the need to disconnect medium voltage electrical conductors and without using a ground reference, the present work describes a methodology based on the analysis of the electric field generated by these Conductors to store energy and infer a voltage in a capacitor of parallel plates with certain characteristics, situated at a certain distance from them. With the use of computational simulation through software based on the Maxwell equations, it is possible to obtain values of the potential difference for systems with single-phase topology and to correlate it with the voltage that generated these electric fields. For a network with two-phase and three-phase topology, it was not possible to perform this correlation, however there is room to apply digital seeding techniques of sources with the purpose of discriminating the contribution of each phase in the sensor element. Wed, 22 Feb 2017 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/10165 2017-02-22T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/9456 Design and simulation of a RISC-V dual-core lockstep for fault tolerant systems Viana, Rafael de Figueredo Embedded processors are increasingly being used in every industry and consumer segment, including critical-safety applications. The critical parameter of the processors, previously performance, was replaced by the need to guarantee the reliability of the system. This paradigm shift leads to the use of techniques for the development of fault-tolerant devices. Aerospace and, more recently, automotive applications are more susceptible to failures caused by the incidence of radiation in the integrated circuits that make up the systems, due to the reduction in the size of the transistor and the increase in the complexity of the devices. In this context, the use of FPGA (Field Programmable Gate Array) is attractive to the industry for implementing secure systems, due to the versatility and customization of designs on the devices. However, radiation-resistant FPGA has a high acquisition cost, in addition to being developed with legacy integrated circuit technology if compared with FPGA COTS (Commercial Off the Shelf). To increase the reliability and security of systems implemented in FPGA COTS, this work implements a dual-core Lockstep (DCLS) system for open-source processors architecture RISC-V, using the RI5CY core. We believe that this is the first work that implements a DCLS architecture with RISC-V cores, performs a fault injection routine via software, and evaluates its hardware and software overhead. A fault injection framework is proposed and implemented using an open-source simulation tool. The system is implemented in FPGA and the hardware overhead is small, reaching just over 5.18% compared to a single RI5CY core. The maximum clock frequency reduction achieved by the system implemented in a Xilinx Kintex KC705 reached 18.5%. Fault injection results indicate that the system is effective in detecting faults at the outputs of colors, where all visible errors were detected. Fault injection tests shows the discrepancy between transient and permanent fault injection in the Design Under Test due to the difference between visible errors. Fri, 31 Jul 2020 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/9456 2020-07-31T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/9455 Desenvolvimento de um sensor por software para o monitoramento da concentração de partículas em salas limpas: estudo de caso: Instituto itt Chip/UNISINOS Flores, Esmael de Oliveira There is a significant potential for energy savings in cleanroom air conditioning or HVAC (Heating, Ventilation, and Air Conditioning) systems. Important components of these systems, insufflators, or fans, which recirculate clean air constantly and for this reason are assets that demand high energy costs. Several publications report that the airflow in cleanrooms is usually projected above the required value. At the same time, several published studies propose models for estimating particle concentration in cleanrooms, considering several operational characteristics. In this work, a new approach is proposed, airflow (air change per hour) is estimated and supplied to the controlled environment according to demand, generating energy savings by reducing fan speed. This technique uses a softsensor composed of a cleanroom particle concentration estimation model. Two softsensors technologies are used to achieve the proposed objective: the first one uses an estimation model with parameter correction through non-linear optimization with restrictions, while the second uses a Kalman filter estimator, even with measurement noise. As a case study, one of the cleanrooms of Unisinos itt-Chip Institute was used. The results revealed that under certain conditions and scenarios of room use, it is possible to reduce up to 75,6% of the energy consumed by the HVAC system fan. Tue, 14 Jul 2020 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/9455 2020-07-14T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/9387 Analisador de Non-Volatile Memory Express baseado em Field-Programmable Gate Array Linden, Vinícius Gabriel The usage and development intensification of Solid-State Drive (SSD), in varying applications, open up the optimization possibilities for the legacy techniques acquired from the outdated Hard Disk Drives (HDD). For this reason, a committee made of the leading flash memory technology manufacturers has put forward a new standard for the communication protocol, named Non-Volatile Memory Express (NVMe). This protocol was created with the end goal of suppressing the performance penalties imposed by the software layer, leaving the hardware more standardized with a high degree of parallelism and performance. Due to industrial secret, manufacturers do not share the protocol implementation’s details. This makes recent literary resources scarce to the academia, with the most relevant papers published by the industry itself. All of this contributes to turn the SSD development out of reach for the third-party researchers, limiting the academic contribution. For this reason, this project presented a solution for enabling the research of both the NVMe protocol and SSD’s characteristics, making a flexible platform for this development: a benefit for both the industry and academia. By employing programmable logic in the project’s implementation, greater flexibility and versatility was allowed. The current State of the Art presents one with no research that put forward such a platform exclusively aimed at SSD development and protocol analysis. This work focuses in the implementation and testing of real time logic in commercial hardware. Solutions for acquiring NVMe protocol data and enabling to memory access optimization were presented, in form of three different systems: a field capture and storage; a NVMe command counter by function, capable of restricting its count by numeric fields; and a NVMe switch, which decides where to send the commands based on their own content. Command count and captured fields are visible through an external interface and configurations are introduced at runtime, through the same interface. It is believed that these systems fill the gap between the new guidelines and access availability to research — not only for the main manufacturers, but most importantly for academia. Thu, 13 Aug 2020 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/9387 2020-08-13T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/9386 Avaliação e validação dos requisitos de uma rede de distribuição de energia para um circuito integrado switch ethernet de 3,2 Tbps Timm, Diego Augusto The importance of the Power Distribution Network (PDN) characterization, for high performance Integrated Circuits (IC), through simulation, is addressed in this work. This work comprises the simulation and measurement of the path behavior between the power source output and the IC. This path corresponds to the PDN of study case circuit. The PDN power integrity is one of the factors that guarantee the signal integrity and the signal integrity guarantees the information transmission from the transmitter to the receiver. Currently, high-speed digital projects are crossing the 1 Gbps information exchange barrier (bit switching) and increasingly demand for low-noise power. The high-performance ICs, responsible for this high data transmission rate, are reaching 3.2 Tbps throughput and require power sources with voltages below 1 V and currents in the order of hundreds of Amperes. In this work, the power integrity of a Printed Circuit Board (PCB) is evaluated based on the behavior of the PDN voltage drop and the PDN impedance. The results are validated with simulations and measurements performed on a PCB Case Study. The PCB uses an Ethernet Switch IC in a 2.4 Tbps throughput application. Is also, an analysis performed for until 3.2 Tbps throughput. The methodology adopted in this work for tasks execution was the appropriate engineering triangle, composed by the understanding, simulation and measurement. This work presents the simulations, analyzes and results obtained and reinforces the importance to use simulators to predict occurrences even before the manufacture of prototypes. It presents too the PDN measurement using different instruments, the care and restrictions of the instrumentation, as example, the set of instruments formed by a signal generator and an oscilloscope that can be a great alternative to the lack of a Vector Network Analyzer (VNA), to carry out the qualitative characterization of the impedance certain PDNs. Tue, 24 Mar 2020 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/9386 2020-03-24T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/9273 Desenvolvimento de sensor de pressão para aplicação industrial Pereira, Ricardo dos Santos This work presents the piezoresistive sensor technologies used in pressure measurement. Pressure sensors are used in a wide range of applications, among which the industrial area has an important market share. The work covers the history of pressure sensors and also the knowledge necessary to carry out the design of a piezoresistive pressure sensor for industrial use. The analysis of the mechanical deformation of the elastic element of the sensor is a very important part of its design. The information and details needed to design the pressure sensor are listed. The work presents some design considerations that must be observed during its development. The operating principle of piezoresistive sensors is also presented, which is a fundamental element for understanding the proposed sensor. The deformation piezoresistor element used in the development of the project is highlighted. It is a silicon piezoresistor, whose design and manufacture has been fully developed nationally. The work describes the methodology used in the design, construction and how the materials used in the pressure sensor were chosen. The design of the pressure sensor was tested and validated through simulation in the COMSOL software. After the construction of prototypes of the pressure sensor, they were characterized. Two different electrical connection processes for the piezoresistor elements were designed, manufactured and tested: wire bonding and conductive adhesives. Pressure sensors manufactured by wire bonding presents better performance and less dependence on operating temperature variation. A method for the sensor thermal compensation was proposed and implemented. A significant reduction in sensor error was thus obtained. The sensor without thermal compensation has an error 5.5 times greater than the sensor that has the proposed thermal compensation method. Tue, 24 Mar 2020 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/9273 2020-03-24T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/9272 Instrumentação eletrônica para um sistema de auxílio a avaliação de evolução de falhas em motores de indução, por meio do sensoriamento “sem contato” de corrente Kuhn, Henrique Cafruni Wed, 18 Mar 2020 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/9272 2020-03-18T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/9271 Manutenção de linhas de transmissão: metodologia multicritério para priorização da correção de defeitos em linhas de transmissão Vier, Gustavo Bystronski In the electrical sector, interruptions in the transmission system due to unforeseen disconnections generate great inconveniences for utilities and society, in addition to high financial losses. Therefore, it´s established the need for the public electricity transmission service to be carried out with excellence and associated with high levels of availability of the assets. It´s confirmed that a great part of the unavailability of the transmission systems occurs in the transmission lines, which have a big variety and quantity of defects that need to be corrected before they evolve to failures. Thus, it is necessary to establish the criteria for prioritization of defect correction, in a scenario where, normally, the available resources are not sufficient to perform all necessary maintenance activities. The problem of prioritization of defects to be corrected in transmission lines was not observed in other studies, but it´s verified that the Multiple-criteria Decision Analysis methods (MCDA) are adequate tools for this development. This work is about establishing a methodology to prioritize the defects that must be corrected in transmission lines of a transmission concessionaire, through the MCDA Analytic Hierarchy Process (AHP). It takes into account the technical characteristics of the defects and their potential to cause a failure, in addition to the systemic importance of transmission lines and the regulatory impact of their unavailability. A useful tool for management of maintenance teams has been developed, which systematizes and facilitates the correct allocation of resources that are limited, objectively providing the sequence of defects that must be corrected by maintenance teams. Thu, 11 Jul 2019 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/9271 2019-07-11T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/9114 Sistema de controle baseado em psicrometria aplicado à sistemas HVAC: estudo de caso, sala limpa do Instituto itt Chip / UNISINOS Pereira, Tiago Anacleto The present work presents the development of a new control system based on psychrometrics applied to HVAC (Heating, Ventilation, and Air Conditioning) systems. The purpose aims to reduce the energy consumption of the HVAC system of a cleanroom of the Technological Institute in Semiconductors - ITT Chip / UNISINOS. The study reviews the fundamentals and principles of psychometrics, a literature review, the audit of control engineering and automation of the legacy system, the development, and integration of a supervisory system, and the development of the proposed control structure of the system. This system consists of a structured control logic that determines based on the calculation of enthalpies and thermal loads the reference values for the PID controllers and the cycle condition that the system must operate. The tuning of the PID controller parameters was performed based on the process models. An analysis of the proposed control system performance against reference tracking and disturbance rejection under different scenarios as well as an analysis of energy consumption is performed and compared with the legacy system. The results reveal the effectiveness of the proposed system due to its superior performance and lower power consumption compared to the legacy system. Thu, 12 Sep 2019 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/9114 2019-09-12T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/9066 Desenvolvimento e análise comparativa de soluções para teste funcional de memória DRAM em testador automático industrial versus testador manual de bancada Jaeger, Gabriel Antônio The qualification of the manufacturing process can guarantee the desired quality and reliability of the products produced. For this, it is essential to understand the functional behavior of electronic components and the main characteristics of their failures. On the other hand, the constant technological advancement and the increase in the complexity of the devices adds difficulty in the test steps, because with the increase of memory density and data speed rate, besides the increasingly complex structures, the challenges related to the applied test strategies, while imposing the need for a thorough knowledge of the developed devices. In addition, the constant evolution of the Brazilian market in the semiconductor sector presents an even greater need for process improvement and industrial level testing capabilities, in order to add value, quality and generate competitiveness with the international market. Based on this context, the objective of this work is the development and validation of a functional electrical memory test program for use in a high performance industrial Automatic Test Equipment (ATE), and later a comparative analysis between the developed test solution and a benchtop tester (Turbocats TCE3200LP). The target devices of this work are the DDR4 SDRAM memories. The test platform used in the project was Teradyne’s ATE Magnum V, for which one the test program was developed, which used some of the main memory testing algorithms found in the literature and suitable for SDRAM memory testing. The functional validation of the test development, as well as the comparative analysis, was performed through the results adherence analysis between failures detected by the ATE test program and the failures detected through the existing algorithms in the TCE3200LP platform. The adherence level of the results between the developed test solution and the bench testers was 47%. However, the adherence between the ATE test and the selected samples was approximately 80%, showing greater similarity with the actual condition of each sample compared to the result obtained by the TCE2300LP. In other words, the failure coverage index of the developed test solution yields better results than the TCE3200LP bench tester solution and is an interesting alternative for use in fault analysis and defect characterization. Wed, 06 Nov 2019 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/9066 2019-11-06T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/9065 Controle preditivo aplicado a um sistema HVAC: Estudo de caso: Sala limpa do Instituto itt-Chip/UNISINOS Santos, Cristian Figueiredo dos This work presents the development of an advanced, application-level control system, aimed at improving energy consumption levels in the itt-Chip / Unisinos cleanroom facilities. Heating Ventilation and Air Conditioning (HVAC) systems account for a large portion of semiconductor production costs due to the need for temperature, humidity and internal pressure control of controlled environments. Considering that most of the world’s buildings require climate control systems, there is a need for simplified HVAC systems. To address the great potential for new contributions to the semiconductor market, an application-level, multivariable predictive control system was developed to meet the control specifications required by the clean rooms of the technological institute. To obtain the synthesis of the predictive controller, an evaluation of the original control system was necessary, including process characterization and parametric modeling from response test analysis. A Simulink® application was developed using Model Predictive Control (MPC) and Open Platform Communications (OPC®) toolboxes for processing control laws and communication with actuators through local programmable logic controllers. At the application level, servo and regulatory behavior tests of the predictive controller, and the evaluation of an energy consumption indicator (ECI) were developed to compare the itt-Chip PID legacy control and the new advanced control strategy was implemented. The results indicated a good servo and effective regulatory behavior of the MPC control, and a reduction in energy consumption where the indicator read values between 80 and 90%, depending on the tuning chosen for the predictive control. Mon, 23 Sep 2019 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/9065 2019-09-23T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/9064 Assinatura elétrica de falhas paramétricas para diagnóstico de defeitos de soldagem de fios em encapsulamento MCP Nascimento, Rafael Bez This dissertation describes a method of failure signature analysis by acquiring parametric data from 221 FBGA eMCP (embedded Multi Chip Package) encapsulation MMC devices. The objective is to identify the electrical signature of failure modes of the wire welding process through the failure signature represented in I-V curves. The application of the method identified failure modes such as open circuit, short circuit and differences in electrical circuit resistance associated with the inspected pins. The sample set analyzed was four hundred and forty-nine units of an eMCP package. The I-V curves, acquired from the samples with the developed tool and software, differed from the reference samples in 62 % of the cases. Among these samples, it was possible to identify similarities between the I-V curves in 84 % of the units. However, for samples where it was not possible to correlate I-V curves with known failure signatures, the results indicate which subsequent auxiliary methods of the failure analysis flow should be applied. Because data acquisition is done pin by pin. Therefore, this method applies to the location and isolation of the fault mechanism. Tue, 03 Sep 2019 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/9064 2019-09-03T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/8941 Metodologia para mitigação de desligamentos intempestivos em linhas de transmissão correlacionados a umidade elevada Puchale, Leandro Henrique Bona This work deals about the development of methodology to mitigate the problem of unplanned outage in transmission lines, more specifically of transitory nature, that occur in normal operation regime and non-adverse climatic conditions. This problem is observed with greater intensity in transmission lines composed of ceramic insulators (glass or porcelain) and during in wet conditions. The hypothesis analyzed in this dissertation is that the wetting ability of these insulators may cause the formation of a water film that, combined with the contamination on the surface of the insulator, results in momentary flashover in the string. Different methods developed by researchers, companies and manufacturers are used to improve the performance of insulators under these conditions. The application of RTV (Room Temperature Vulcanizing) silicone coating on glass insulation is a method that already shows good results in several countries. This practice combines the mechanical and dielectric strength of the ceramic insulators with the hydrophobicity of the water repellent polymer surface, thus reducing the leakage current and the consequent possibility of disruptive discharge (transmission line outage). The scope of this research is to analyze the performance of the implementation of four (4) different configurations of insulators string with RTV in a transmission line that operates in 230 kV as a solution to mitigate transient outages. The performance of the new configurations is evaluated by comparing the number of outages occurring at the installation locations of each type of configuration, before and after such deployment. In general, the results obtained with the new configurations show the improvement in performance, mainly reflecting the RTV's effectiveness in relation to humidity / contamination. In addition, during the line monitoring stage it was observed that some transient outages have still occurred, not due to the moisture / contamination effect of the insulators surface, but due to a peculiar mechanism caused by birds: the bird streamer. In this context, the methodology developed is characterized by practical applicability, and may serve as a reference for the mitigation of transient outages in transmission lines of other utilities in the electric sector. Mon, 29 Apr 2019 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/8941 2019-04-29T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/7702 Desenvolvimento de cateter implantável de monitorização de pressão intracraniana Rosario, Jeferson Cardoso do The traumatic brain injury (TBI) is nowadays the third cause of death in the world. Recent studies have shown the intracranial pressure (ICP) monitoring as an important tool for cerebral perfusion pressure (CPP) calculation and cerebral blood flow (CBF) assestment, reducing significantly the mortality statistics. Besides TBI, several others pathologies and neurosurgery conditions have been using the ICP monitoring technique. The proposal of ICP monitoring first appeared on the 50’s, where a tube fulfilled with fluid in contact with cerebrospinal fluid (CSF) was introduced into the intracranial space and connected to an external pressure transducer. With the waves of the microelectronics and microelectromechanical systems (MEMS) industry evolution, it was possible to put the transducer and all the electronics inside the catheter tip, allowing a less invasive monitoring, decreasing the risk of infection. The state of art catheters with micro transducer on the tip can be divided into three groups: strain-gauge, optical fiber and pneumatic. Each group has it’s own characteristics, however the first has been demonstrated as the rugged solution, being reliable, cost effective and with good accuracy. In the present work, it was proposed the development of an strain-gauge micro transducer implantable catheter for intracranial pressure monitoring. Functional prototypes were built and submitted to performance tests, according to the technical standards in the medical equipment area, the temperature influence over the pressure measurements was evaluated, as well as the accuracy. The adopted processes are commonly used in the semiconductor packaging industry, however it was considered the application special requirements, adapting the processes to the geometry and materials used, considering the needs of biocompatible materials. Fri, 18 Jan 2019 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/7702 2019-01-18T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/7455 Método de coordenação e seletividade de fusíveis e religadores para redes de distribuição de energia Rocha, Clarissa Argenti Existing power distribution networks are increasingly required as to their reliability, energy distribution companies need to meet the criteria of individual quality indicators. To achieve the efficiency of the network, apply to it the concepts of coordination and selectivity. Looking for this concept the present work presents a method for determination of fuses and automatic circuit reclosers applied in the power distribution network to guarantee its coordination and selectivity. Through the study of the elements of protection, and the knowledge of the characteristics of the network, and how these elements should be dimensioned to be selective and coordinated, a methodology is presented for, using graphs, to determine the value of fuses and automatic circuit reclosers in a power distribution network. In the end, the methodology allows the execution of network maneuvers, and evaluates if the coordination and selectivity of the elements is still valid. For the application of this method, the IEEE network of 34 bars is adapted by adding fuses and automatic circuit recloser to allow validating the concept presented here Fri, 31 Aug 2018 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/7455 2018-08-31T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/7448 Controle dinâmico inteligente para reguladores de tensão de redes de distribuição de energia Carli, Felipe De The electricity generation, transmission, and distribution play a role key in the economic development of a country. The quality and availability of electricity related to distribution has a direct impact on the economy and people's quality of life. Concepts of smart grids has gained more strength in order to improve the quality of services provided. Steady-state voltage is one of the main quality parameters of electrical power in distribution grids and often its control requires solutions of high complexity and investment. Out-of-specification voltage have negative impacts on end-users, as it can cause damage to equipment, outage in key services, and inconvenience to community. In this way, the present work seeks to develop a prototype of intelligent and dynamic control applied to distribution voltage regulators with the ability to collect information of the feeder consumption profile, perform the self-tuning of its parameters and send information to supervisory system. The prototype divided into a control and fuzzy modules was developed on a laboratory scale. Based on loader readings, the device is able to calculate the basic parameters of self-adjustment, ie time delay, dead band and line drop compensation. The overall results of this work show that the development of a dynamic and smart control for step voltage regulators is feasible and can be applied in real distribution grid. The calculation of the time delay, reference voltage, line drop compensation improves the voltage profile of a distribution grid, as it minimizes voltage variations at low and high line loading, according to tests performed with data from a real feeder. It is understood that the overall results of this work serve as a basis for a technical-economic study to extend this control structure to other step voltage regulators in distribution grids. Fri, 26 Oct 2018 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/7448 2018-10-26T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/7322 Influence of minor Zn addition on the microstructural stability of Sn-0.7 wt% Cu solder after aging and electromigration Ilha, Bernardo Bortolotto Tue, 16 Jan 2018 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/7322 2018-01-16T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/7310 Avaliação do arraste dos fios de solda durante o processo de moldagem por transferência no encapsulamento de memórias DRAM Stracke, Márcio Rafael The advancement of microelectronics makes more and more portable electronic devices emerge in our daily lives. This brings a number of challenges to the semiconductor chain, from design, to the development of smaller and more efficient integrated circuits to encapsulation, since the components have become smaller, thinner, and with a larger number of input and output pins. These challenges are present in all chip fabrication processes and we can define molding as a critical process in particular. The transfer molding technology, which is consolidated and the main one used in this process, requires special care in the optimization of its parameters and materials, since there are more and shorter wires realizing the connection between the die and the substrate. The wire sweep, which is the entrainment of the wires due to the flow of the mold compound, becomes a problem, since losses in the molding process imply scrapping the component. The failure rate due to this type of failure can reach 2.5%, according to studies by major semiconductor chain manufacturers disclosed in (SANDGREN; ROTH, 2004). In this project the DRAM memory molding process with BOC BGA encapsulation type was simulated using the FSI module in COMSOL software. Results of wire sweep ratio obtained are within the average adding or subtracting one standard deviation and the maximum error rate ranging was 15.26% considering manufactured boards using the simulation parameters. Wed, 06 Jun 2018 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/7310 2018-06-06T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/7288 Modelo funcional de memória NAND Flash com injeção de falhas caracterizadas Lopes, Guilherme Ferreira Mon, 28 May 2018 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/7288 2018-05-28T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/7021 Desenvolvimento de metodologia de simulação para conformidade em compatibilidade eletromagnética para projetos eletrônicos Comin, Rodrigo The national automotive division, more precisely in the bus manufacturing segment, efforts are being deposited to improve the manufacturing quality of its vehicles in order to meet the requirements of the internal and external market through electronic projects based on international standards. Furthermore, the electromagnetic compatibility standards stand out because they have a major importance ensuring that electronic devices are able to provide safety to its users, without interfering or being interfered by other devices. The objective of this research is to develop a methodology to design electronic devices which must meet the standards requirements of electromagnetic compatibility. This goal is achieved through the study of radiated and conducted emissions techniques, and using computational tools for simulation of printed circuit boards. From this study it will be possible to reduce costs with laboratory tests, reduce the time required for development, and provide products to the customers in an efficient way. The use of appropriated techniques and good practices during the designs process are the proper way to meet standards and requirements. However, with the evolution of technology and addition of more electronic circuits in smaller areas requires to acquire more knowledge and go deeper in this study. Thus, it is necessary to understand in details the common mode and differential emissions technics, develop simulations which can provide a preview of what the laboratory tests may result, and propose changes in the mechanic and electronic project design in order to meet the limits of the requirements determined in the standards. Fri, 29 Sep 2017 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/7021 2017-09-29T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/7003 Desenvolvimento de adesivos eletricamente condutivos na fixação de componentes eletrônicos em montagens de superfície (SMT) Lunardi, Tiago di Giovani For many years the most commonly used metal alloy as solder was the Pb-Sn alloy, a malleable material with a low melting temperature. With the European Directive 2002/95/CE (as known as RoHS Directive), the suspension of the use of hazardous substances such as lead is approved. It is necessary to replace the Pb-Sn solder alloy with new materials and the most used of these are the alloys of the SAC family (metal alloy composed by Sn-Ag-Cu). This alloy melts at temperatures above 210°C, which can damage the electronic components, that are becoming smaller and with more functions. The possibility of using electrically conductive adhesives arises. These are mostly formulated using silver particles and other good conducting metals such as gold and nickel, dispersed in a polymer matrix. In this way, there is economy of metals, compared to the use of solder pastes. This work proposes three formulations for electrically conductive adhesives, obtained from an epoxy resin with butadiene with different types of conductive fillers: carbon nanotubes and silver with different morphologies. All the materials were characterized as their physical, morphological and electrical characteristics through MEV, electrical resistance measurement by the 4-point probes method, thermal shock and aging. Electrical resistance of each material and the contact resistance were tested and compared with commercial adhesives and the reference SAC305 alloy solder. It was identified that the adhesives demonstrated resilience in relation to the contact with the PCI even after successive aging cycles at 85°C with 85% RH or thermal shock tests. Electrical resistance measured on the adhesive formulated using silver nanosheets is very close to the values obtained with the commercial reference, in the order of 10-4 cm. It was also the only material that presented less than 20% variation of electrical contact resistance after thermal shock, proving its good performance against the other formulations of this work. Wed, 21 Mar 2018 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/7003 2018-03-21T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/6770 Proposta de um método para priorização de investimento em monitoramento instrumentado contínuo de equipamentos dinâmicos aplicado em planta petroquímica Canal, Luiz Antonio The search for greater industrial safety has been the main guideline in petrochemical business, since the most of accidents are potentiated by the own nature of the operation, which involves flammable, combustible or toxic inventories. Many of the initiators of these events arise from the malfunction of their dynamic equipment, such as motors, pumps and compressors, with causes related to maintenance, operation or design. In this context, it is proposed a method for the implementation of improvements and projects directed to the continuous monitoring of dynamic equipment. The main objective is to increase the industrial safety and the availability, since the continuous monitoring allows a better supervision of the dynamic equipment, besides strengthening the application of condition based maintenance policy. The solution will be presented focusing on the monitoring of equipment temperature and vibration, which indicate of most failures or a situation of non-appropriated operation. This work starts with determining the method to prioritize the implementation, based on multicriteria and risk analysis, explain the criteria and their definition, culminating with the exemplification of the work in a real petrochemical plant. As a result, a risk matrix is presented for support in the prioritization of investment in continuous monitoring, also adding sensitivity analysis simulations for decision making. Tue, 05 Sep 2017 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/6770 2017-09-05T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/6726 Metodologia de modelagem de diferentes dissipadores de calor com resfriamento líquido em microcanais Flores, Édson This work has the objective of modeling different heat sinks with liquid cooling in microchannels. The proposal is the use of fluid dynamics software to analyze the thermal performance in different constructional geometries of microchannels. The software used to perform the CFD simulations was Ansys Fluent R . This work addresses the previous steps required for CFD simulation, highlighting the step of mesh generation for the simulations, involving mesh convergence study, simulation acceptance criteria and refining techniques at the liquid-solid interface, a procedure necessary for Modeling of heat transfer physics. The geometries studied were of rectangular section microchannels in parallel, microchannels of pinched structure and microchannels in fractal network of type H. A case study was also modeled in this work in which parallel microchannels were formed by walls of adhesive material In an aluminum block, in which the results obtained serve to aid in a stage of construction of an experimental prototype. In the study of the microchannels of rectangular section in parallel and microchannels of pinned structure, we varied the dimensional aspects seeking the best response of thermal performance, being expressed in terms of thermal resistance. The simulation of microchannels in fractal network H was performed for a qualitative comparison referring to the other geometries studied. A problem discussed in the course of this work was the need to change the laminar viscosity model to a turbulent viscosity model despite the velocity of the fluid inside the microchannels being low and expressing a low Reynolds number. Techniques for heat removal in microchannels can contribute decisively to the thermal management of a project, the lower energy used for cooling and the reduction of the dimensions of an end product. The geometries studied can be constructed in a metal layer of a metal core type printed circuit board, as well as being present in a one-chip silicon structure. The domain of thermal modeling techniques with fluid dynamics simulators presented in this paper can help in the search for technological solutions for micro-scale heat removal, reduce the need for prototype production, and consequently reduce costs. Fri, 12 May 2017 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/6726 2017-05-12T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/6724 Proposta de uma plataforma reconfigurável para testes de módulos SDRAM DDR3 Lessinger, Samuel This work consists on a proposal of a DDR3 SDRAM memory module reconfigurable test platform. Memory module testers are usually closed architecture systems, in which the user has little flexibility in their use. In this scenario, a low-cost portable platform, which enables the user to describe his own test algorithm becomes interesting. This work explores the use of Field Programmable Gate Arrays (FPGAs) in order to construct a fully reconfigurable testing platform. In this work a Stuck-At-Zero fault injection strategy was proposed and validated. Results report the success in executing fault detection algorithms as well as the software framework developed for the fault injection campaign. Thu, 21 Sep 2017 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/6724 2017-09-21T00:00:00Z http://repositorio.jesuita.org.br/handle/UNISINOS/6540 Avaliação do desempenho e sintonia de controladores de nível Andreis, André Augusto Industrial processes are of a dynamic nature, varying continuously in time due to external disturbances or changes in the process and, therefore, the need for automatic control of variables is a reality, mainly due to the complexity increase of the systems installed in last decades. Due to the importance of controllers, this research brings the study of techniques for performance assessment and tuning of level controllers, as well as guides the choice of indexes to be used for the performance assessment of level controllers, according to the control objective, presenting the magnitude of the error obtained when used an inadequate performance assessment index. It addresses level control systems that aim to maintain the level in the reference accurately or minimize the outlet flow variance. It is presented a proposal of methodology for performance assessment and tuning of level controllers through process modeling and solving an optimization problem. The proposed methodology is applied to a self-regulatory process. The effectiveness of the performance assessment index for level controllers is explored, considering different types of perturbation in the inlet flow. Traditional techniques and optimization techniques for controller tuning are compared, being that optimization techniques present better results than traditional techniques. It is presented the uncertainties impact in the model used to obtain the controller parameters through optimization techniques in which, depending on the control objective and the type of input disturbance, there are discrepancies to be considered in relation to the need for controller retuning. The consequences of using inadequate performance assessment index are analyzed. Through the obtained results it was verified that to determine the adequate index for the performance assessment level controllers one must identify correctly the control objective, which does not always occur, since the systems of support to the decision in general provide performance assessment indexes that consider the process variable, but some control meshes may consider the manipulated variable. Thu, 22 Jun 2017 00:00:00 GMT http://repositorio.jesuita.org.br/handle/UNISINOS/6540 2017-06-22T00:00:00Z