Development of a spectrum analyzer based on FPGA

Dissertação de mestrado em Engenharia Eletrónica Industrial e Computadores Sistemas Embebidos e ComputadoresA electrónica no setor automóvel evoluiu imenso durante as duas últimas décadas. A evolução destes sistemas obrigou ao desenvolvimento dos sistemas de comunicação dos veículos, a fim de manter tudo sincronizado, e apesar de terem uma maior eficiência, consomem mais energia, o que significa que as fontes de energia destes sistemas terão que ser mais sofisticadas devido ao número elevado de fre quências de funcionamento. Além disso, cada dispositivo eletrónico contém numerosas unidades de processamento que operam em frequências diferentes, emparelhadas com várias interfaces de comuni cação. Devido a isto, houve a necessidade de criar regras de conformidade electromagnética (CEM), que impõem testes extensivos para cada dispositivo electrónico, o que fez também aprimorar as regras de conformidade electromagnetica a que estes dispositivos são sujeitos e torná-las cada vez mais restritivas. Estas regras estão centradas tanto nos sinais emitidos pelo dispositivo como na sua capacidade de resistir a interferências. Para responder à necessidade de um equipamento mais especializado para a resolução de problemas e testes de conformidade, foi utilizada uma Field Programmable Gate Array (FPGA) e um Analog to Digital Converter (ADC) de baixo custo para desenvolver um dispositivo capaz de captar sinais e calcular o seu espectro. Foi utilizada uma arquitectura heteródina para obter uma melhor resolução através da partição do sinal adquirido a partir do ADC. Esta arquitetura é uma técnica de processamento digital de sinal bastante utilizada actualmente, onde são utilizados um oscilador local, um misturador e um filtro passa baixo. Após segmentar o sinal, é calculado o espectro do segmento do sinal em causa através do algoritmo Fast Fourier Transform (FFT) e a sua potência através do algoritmo Coordinate Rotation Digital Computer (CORDIC). Com esta arquitectura foi possível reduzir a utilização de recursos do sistema, no entanto, devido a limitações na memória Block RAM (BRAM) da FPGA, não foi possível obter um baixo nível de ruído de fundo. Apesar desta limitação, o dispositivo desenvolvido pode ser utilizado para identificar frequências de funcionamento que causem problemas de não conformidade. Este instrumento é essencial para a deteção de sinais na gama de testes de emissões conduzidas, particularmente na gama de Very High Frequency (VHF), onde os sinais de baixa potência podem ser difíceis de distinguir do ruído.Electronics in the automotive sector have advanced drastically during the last two decades. The evolution of these systems has required the development of vehicle communication systems in order to keep everything synchronized, and although they are more efficient, they consume more energy, which means that the power sources for these systems will have to be more sophisticated due to the high number of operating frequencies. In addition, each electronic device contains numerous processing units operating at different frequencies, paired with various communication interfaces. Because of this, the Eletromagnetic Compliance (EMC) guiding standards have also evolved accordingly and imposed more restrictions on devices, expanded test bands and imposed newer test scenarios. These rules focus on both the signals emitted by the device and its ability to resist interference. To address the need for more specialized equipment for troubleshooting and compliance testing, a low cost Field Programmable Gate Array (FPGA) and Analog to Digital Converter (ADC) were used to develop a device capable of capturing signals and calculating their spectrum. An heterodyne architecture was employed to achieve better resolution by partitioning the acquired signal from the ADC. This architecture is a widely used digital signal processing technique today, where a local oscillator, a mixer and a low-pass filter are used. After partitioning the signal, the spectrum of the signal segment in question is calculated using the Fast Fourier Transform (FFT) algorithm and its power using the Coordinate Rotation Digital Computer (CORDIC) algorithm. With this architecture it was possible to reduce the resource usage of the system, however, due to limitations in the FPGA’s block RAM (BRAM), it was not possible to achieve a low noise-floor. Despite this limitation, the developed device is aimed at EMC troubleshooting and can be used to identify operating frequencies that cause non-compliance problems. This instrument is essential for signal detection in the range of conducted emissions, particularly in the Very High Frequency (VHF) range, where low power signals can be difficult to distinguish from noise

Information systems for industrial processes support and optimization

This paper presents the Document Management Systems (DMS) as a support decision tool to optimize Toyota Caetano Portugal S.A. (TCAP) processes performance. The created systems were developed on the best practices of a Business Project Management (BPM), for better structural implementation. The first system implementation was related to the warehouse materials requirement process, where an excel template with VBA functions for fill automatization was built. It had a reduction of the overall paper consumption and time execution optimization, which means the gain of approximately of 0,10€ and 2,09€ per unit produced, respectively. It was also obtained an elimination of 4538 paper sheets per year. A second system was also developed, in order to provide a Decision Support System (DSS) for documental management. Several User Forms were developed in VBA code in order to provide a flexible and intuitively user interface experience. It reduced the users time decision making and the administrator maintenance, by a total of 26 minutes, corresponding to a 1,61€ reduction per unit built, which means an efficiency increase of 42%. The present work fits in the company's strategy for a more sustainable environment being a positive driver of Industry 4.0 implementation.info:eu-repo/semantics/publishedVersio

Pulmonary Actinomycosis: A Diagnostic Challenge

Pulmonary actinomycosis is an uncommon and challenging infectious disease with non-specific symptoms and imaging findings. The authors report a case of a 68-year-old man with diabetes and a history of past smoking who presented with anorexia and weight loss with no significant findings on physical examination. A parenchymal consolidation in the anterior segment of the right upper lobe was detected after a chest computed tomography (CT). Bacterial colonies of Actinomyces species were identified in the histology of transbronchial biopsy. Imaging reassessment after six weeks of treatment with oral amoxicillin showed progression with a high metabolism 10.5 standardized uptake value (SUV) documented on the f-fluorodeoxyglucose positron emission tomography/CT. Concern about the possibility of lung cancer was raised and ruled out by a negative transthoracic needle biopsy. The diagnosis of pulmonary actinomycosis with pyogenic superinfection was presumed. The patient was successfully treated with intravenous amoxicillin and clavulanate for two weeks, followed by six months of oral treatmentinfo:eu-repo/semantics/publishedVersio

Development of a grooming process for an agile software team in the automotive domain

At the current unpredictable technical evolution, the market is demanding an increasingly flexibility from companies to adapt to the pace of change in what customers want. The present research was developed in an automotive company, where software teams are pursuing Agile methodologies to coupe with these challenges. Teams use the Scrum framework, however, lack of efficient communication among team members results in poor performance of the product owner and the development team. In an attempt to solve this issue and according to the needs shared by the teams, this paper proposes a grooming process for a Scrum team. It provides a step-wise approach to work breakdown, from customer requirements elicitation to the development of ready work entities using the user story format. This paper describes how agile methods can support requirements engineering in a software project.This work is supported by: European Structural and Investment Funds in the FEDER component, through the Operational Competitiveness and Internationalization Programme (COMPETE 2020) [Project nº 002797; Funding Reference: POCI-01-0247-FEDER-002797

Passing Through a Hole: Delayed Diaphragmatic Hernia After Cytoreductive Surgery

A diaphragmatic hernia is a protrusion of abdominal contents into the thoracic cavity. Although it is commonly congenital, diaphragmatic hernias can also be acquired. Blunt or penetrating trauma are among the most frequent causes, although spontaneous or iatrogenic cases have been reported. Recently, some case reports related to diaphragmatic hernia after debulking surgery for advanced ovarian cancer have been described. This is an exceedingly rare but life-threatening complication, being prompt recognition and surgical correction critical. We report a case of a delayed diaphragmatic hernia in a 19-year-old female resulting from cytoreductive surgery for advanced ovarian cancer. Rapid evolution from gastrointestinal symptoms to hypovolemic shock occurred, and intensive care admission was required. Immediate surgery was critical to improving the patient outcome. This case highlights this uncommon but life-threatening complication, the challenges of diagnosing and managing those patients, and the need for early recognition, support, and surgical correction.info:eu-repo/semantics/publishedVersio

Pneumocephalus Following an Accidental Dural Puncture, Treated Using Hyperbaric Oxygen Therapy. A Case Report

Introduction: Neuraxial techniques, including epidural anaesthesia, are often used for perioperative pain control and are generally safe. However, both transient, mild and even severe, life-threatening neurologic complications can occur. Case presentation: A seventy-eight-year-old man was admitted to the hospital for a radical nephrectomy plus transurethral resection due to kidney and bladder cancer. During the epidural exploration, an accidental dural puncture was noted. This was followed by the patient complaining of an intense headache. The epidural catheter was placed in a different location, and surgery was performed uneventfully. The patient presented with confusion, agita-tion, vertical nystagmus, vision loss, and paraparesis about two hours later. The epidural levobupivacaine and mor-phine infusion were stopped, followed by motor block resolution. A computerized head-tomography scan showed extra-axial multiple air spots involving the frontal and temporal lobes. Emergent hyperbaric oxygen therapy was commenced. After a single session, there was complete resolution of all symptoms and a marked reduction in the number and volume of the extra-axial air visible on the CT scan. Conclusions: Although rare, pneumocephalus is a well-recognized complication of a dural puncture. Its rapid recognition in a patient with new-onset neurological symptoms and early treatment with hyperbaric oxygen therapy allows rapid clinical and imaging resolution and an improved prognosis.info:eu-repo/semantics/publishedVersio

Assessment of ammonia and carbon dioxide concentrations in a breeding hen building under Portuguese winter

info:eu-repo/semantics/publishedVersio

Melhoria de desempenho de processo de tratamento de reclamações e gestão de stocks de produto intermédio numa empresa do setor automóvel

Dissertação de mestrado em Engenharia de Sistemas (área de especialização em Logística)O presente trabalho foi desenvolvido numa empresa do ramo automóvel, cuja finalidade é a produção de antenas. Foi realizado no âmbito do projeto de dissertação do 2º ano do Mestrado em Engenharia de Sistemas, ramo de especialização em Logística. Os principais objetivos da dissertação assentaram na melhoria de desempenho do processo de tratamento de reclamações de produto não conforme por parte do Cliente e na gestão de stocks de produto acabado e Work-in-Process (WIP) não conforme que seguem para as fases de Análise e Retrabalho, respetivamente. Deste modo, pretendeu-se reduzir o desperdício e aumentar a eficiência nos dois processos. A metodologia de investigação usada neste estudo foi a metodologia Investigação-Ação. Assim, foi realizada a revisão da literatura acerca do Lean Manufacturing e dos seus princípios e ferramentas, do tratamento de reclamações, da redução de stocks e da Simulação em Arena. Através do estudo do processo de tratamento de reclamações de antenas não conformes por parte do Cliente e do processo produtivo de peças não conforme da empresa, foi realizado um diagnóstico à situação atual. Recorrendo às ferramentas Lean como fluxogramas, Análise de Pareto e Diagrama de causa-efeito (Diagrama de Ishikawa), à realização de auditorias internas às linhas de produção bem como o recurso ao uso da Simulação em Arena, foram identificadas algumas fontes de desperdício, nomeadamente, o excesso de campos no software utilizado para a gestão de reclamações por parte do Cliente, o que dificulta na análise de dados, e o elevado número de produto não conforme em stock na Análise e Retrabalho. A utilização adequada destas ferramentas permitiu identificar os principais problemas e as suas causas, para os processos em estudo. Com base neste conhecimento foram propostas ações de melhorias que passaram pela reformulação do software utilizado pela organização e pela contratação de mais trabalhadores para as fases da Análise e Retrabalho. Com a implementação das ações propostas, prevê-se (pelo modelo de simulação implementado) uma redução do stock de produto acabado não conforme na ordem dos 96% para a fase da Análise e uma redução idêntica para o produto intermédio não conforme, para fase do Retrabalho. Devido à curta duração do estágio curricular onde a dissertação foi realizada, as propostas não foram implementadas, sendo recomendada a sua adoção no futuro.The present work was developed in an automobile company, whose purpose is the production of antennas. It was carried out within the scope of the dissertation project of the 2nd year of the Master in Systems Engineering, Logistics branch. The main objectives of the dissertation were to improve the process of product that went back to the company because it was not according to Customer’s specifications and the stock management of non-conforming and Work-in-Process (WIP) product that go to Analysis and Rework phases, respectively. Thus, it was attempted to reduce waste and increase efficiency on both processes. The research methodology used in this study was the Research-Action methodology. Thus, a review of the literature on Lean Manufacturing and its principles and tools, handling complaints, stock reduction and Arena Simulation was carried out. Through the study of how the management of defective antennas is done by the Quality department and the productive process of non-conforming product of the Production department is done, a diagnosis was made to the current situation. Using Lean tools such as flowcharts, Pareto Analysis and Cause-Effect Diagram (Ishikawa Diagram), internal audits to the production line and the use of Arena Simulation, some source of waste were identified such as excess of fields on the software used for the management of complaints by the Customer, which makes data analysis difficult, and the high number of non-conforming product that is on stock at Analysis and Rework phases. The proper use of these tools allowed to identify the main problems and their causes for the processes under study. Actions were presented for improvements that went through the reformulation of the software used by the organization and the hiring of more workers for the Analysis and Rework phases. With the implementation of the presented actions, a reduction of the non-conforming finished product stock in the order of 96% for the Analysis phase is expected (by the simulation model implemented) and a similar reduction for the defective WIP product for the Rework. Due to the short duration of the curricular internship where the dissertation was held, the suggestions were not implemented and its implementation are recommended in the future

Deep dense and convolutional autoencoders for machine acoustic anomaly detection

Recently, there have been advances in using unsupervised learning methods for Acoustic Anomaly Detection (AAD). In this paper, we propose an improved version of two deep AutoEncoders (AE) for unsupervised AAD for six types of working machines, namely Dense and Convolutional AEs. A large set of computational experiments was held, showing that the two proposed deep autoencoders, when combined with a mel-spectrogram sound preprocessing, are quite competitive and outperform a recently proposed AE baseline. Overall, a high-quality class discrimination level was achieved, ranging from 72% to 92%.European Structural and Investment Funds in the FEDER component, through the Operational Competitiveness and Internationalization Programme (COMPETE 2020) - Project n ∘ 039334; Funding Reference: POCI-01-0247-FEDER-039334