Dense, sonar-based reconstruction of underwater scenes

Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Mechanical Engineering at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2019.Three-dimensional maps of underwater scenes are critical to—or the desired end product of—many applications, spanning a spectrum of spatial scales. Examples range from inspection of subsea infrastructure to hydrographic surveys of coastlines. Depending on the end use, maps will have different accuracy requirements. The accuracy of a mapping platform depends mainly on the individual accuracies of (i) its pose estimate in some global frame, (ii) the estimates of offsets between mapping sensors and platform, and (iii) the accuracy of the mapping sensor measurements. Typically, surface-based surveying platforms will employ highly accurate positioning sensors—e.g. a combination of differential global navigation satellite system (GNSS) receiver with an accurate attitude and heading reference system—to instrument the pose of a mapping sensor such as a multibeam sonar. For underwater platforms, the rapid attenuation of electromagnetic signals in water precludes the use of GNSS receivers at any meaningful depth. Acoustic positioning systems, the underwater analogues to GNSS, are limited to small survey areas and free of obstacles that may result in undesirable acoustic effects such as multi-path propagation and reverberation. Save for a few exceptions, the accuracy and update rate of these systems is significantly lower than that of differential GNSS. This performance reduction shifts the accuracy burden to inertial navigation systems (INS), often aided by Doppler velocity logs. Still, the pose estimates of an aided INS will incur in unbounded drift growth over time, often necessitating the use of techniques such as simultaneous localization and mapping (SLAM) to leverage local features to bound the uncertainty in the position estimate. The contributions presented in this dissertation aim at improving the accuracy of maps of underwater scenes produced from multibeam sonar data. First, we propose robust methods to process and segment sonar data to obtain accurate range measurements in the presence of noise, sensor artifacts, and outliers. Second, we propose a volumetric, submap-based SLAM technique that can successfully leverage map information to correct for drift in the mapping platform’s pose estimate. Third, and informed by the previous two contributions, we propose a dense approach to the sonar-based reconstruction problem, in which the pose estimation, sonar segmentation and model optimization problems are tackled simultaneously under the unified framework of factor graphs. This stands in contrast with the traditional approach where the sensor processing and segmentation, pose estimation, and model reconstruction problems are solved independently. Finally, we provide experimental results obtained over several deployments of a commercial inspection platform that validate the proposed techniques.This work was generously supported by the Office of Naval Research1, the MIT-Portugal Program, and the Schlumberger Technology Corporation

Os municípios do distrito de Setúbal: análise comparativa orçamental, económica e financeira de 2010 e 2011

Comunicação apresentada em XIV Congresso Internacional de Contabilidade e Auditoria, LisboaA Contabilidade na Administração Local, veio potenciar o cálculo e comparação de indicadores de desempenho a nível orçamental e económico-financeiro, e assim permitir uma melhoria na avaliação da gestão das instituições. O principal objectivo do nosso trabalho é o de evidenciar, para os anos de 2010 e 2011, através do uso de diferentes indicadores selecionados com base no anuário financeiro dos municípios portugueses, o desempenho comparativo e evolutivo dos municípios do distrito de Setúbal, quer ao nível de indicadores orçamentais, quer ao nível de indicadores económicofinanceiros

O relatório de gestão e a avaliação e comparação do desempenho dos municípios portugueses: o caso dos municípios no distrito de Setúbal

Comunicação apresnetada em XXII Jornadas Luso Espanholas, Vila RealA obrigatoriedade da articulação da contabilidade, orçamental, patrimonial e analítica, no Sector Público Administrativo, face ao actual quadro legal, necessita de planos sectoriais. O Plano Oficial de Contabilidade das Autarquias Locais é o plano sectorial de aplicação obrigatória nas Autarquias Locais. A aplicação deste plano no sector autárquico, deverá, entre outros, permitir o cálculo e divulgação de indicadores que permitam a avaliação e comparação do desempenho dos municípios. O objectivo deste estudo centra-se na análise comparativa do desempenho dos municípios do distrito de Setúbal, com base nos indicadores divulgados no Relatório de Gestão. Os resultados demonstram que os municípios apresentam fundamentalmente indicadores de carácter orçamental e/ou patrimonial. Apresentam no total 115 diferentes indicadores orçamentais e 44 indicadores económicos e/ou patrimoniais, o que não permite a comparabilidade. A divulgação no Relatório de Gestão das Autarquias Locais dos mesmos indicadores permitiria uma avaliação comparativa do desempenho dos municípios.In the legal framework for public sector accounting, the mandatory articulation between budgetary, patrimonial and management accounting systems, induces in the need of sectorial plans. Thus, a specific accounting plan for the Local Government sector was approved and enforceable for municipalities. This plan, should among other things, allow the calculation and reporting of indicators for evaluating and comparing the performance of municipalities. The aim of this study focuses on the comparative analysis of municipalities performance in Setúbal district based on indicators disclosed in the Management Report. The results show that in the municipalities’ management reports the indicators are primarily of budgetary and patrimonial nature. In total was disclosed, 115 different indicators of budget and 44 of economic and patrimonial nature, which does not allow municipalities’ comparability. Therefore, we think that, the use of a group of indicators common to all entities, would improve the assessment to a comparative performance of municipalities

A aplicação da rendibilidade supranormal para a avaliação da criação de valor

Comunicação apresentada em XXIII Jornadas Hispano‐Lusas De Gestión Científica - Málaga, 7, 8 y 9 de febrero de 2013No contexto empresarial, caracterizado pela inovação constante e pela competitividade global, a criação de valor assume cada vez maior importância na tomada de decisão e na sustentabilidade das organizações. Este estudo aborda o problema associado às diferentes metodologias utilizadas na avaliação da viabilidade económica e financeira, aquando da decisão de criação de empresas, e na monitorização da evolução dos negócios. Nos estudos de viabilidade utilizam-se normalmente indicadores com base em fluxos de caixa previsionais, enquanto na análise económica e financeira periódica, as empresas recorrem a indicadores que se podem calcular directamente das demonstrações financeiras. Assim, torna-se difícil confrontar as realizações com as previsões e objectivos iniciais. Respondemos a esta problemática, através do conceito Rendibilidade Supranormal que estabelece um elo de ligação entre a decisão de criar o negócio e a sua sequente monitorização, garantindo ao investidor uma imagem real da capacidade de criação de valor e um maior poder para a decisão

Design of boundary-scan testing in CMOS image sensors for industrial applications: internship repor

Tests on printed circuit boards and integrated circuits are widely used in industry,resulting in reduced design time and cost of a project. The functional and connectivity tests in this type of circuits soon began to be a concern for the manufacturers, leading to research for solutions that would allow a reliable, quick, cheap and universal solution. Initially, using test schemes were based on a set of needles that was connected to inputs and outputs of the integrated circuit board (bed-of-nails), to which signals were applied, in order to verify whether the circuit was according to the specifications and could be assembled in the production line. With the development of projects, circuit miniaturization, improvement of the production processes, improvement of the materials used, as well as the increase in the number of circuits, it was necessary to search for another solution. Thus Boundary-Scan Testing was developed which operates on the border of integrated circuits and allows testing the connectivity of the input and the output ports of a circuit. The Boundary-Scan Testing method was converted into a standard, in 1990, by the IEEE organization, being known as the IEEE 1149.1 Standard. Since then a large number of manufacturers have adopted this standard in their products. This master thesis has, as main objective: the design of Boundary-Scan Testing in an image sensor in CMOS technology, analyzing the standard requirements, the process used in the prototype production, developing the design and layout of Boundary-Scan and analyzing obtained results after production. Chapter 1 presents briefly the evolution of testing procedures used in industry, developments and applications of image sensors and the motivation for the use of architecture Boundary-Scan Testing. Chapter 2 explores the fundamentals of Boundary-Scan Testing and image sensors, starting with the Boundary-Scan architecture defined in the Standard, where functional blocks are analyzed. This understanding is necessary to implement the design on an image sensor. It also explains the architecture of image sensors currently used, focusing on sensors with a large number of inputs and outputs.Chapter 3 describes the design of the Boundary-Scan implemented and starts to analyse the design and functions of the prototype, the used software, the designs and simulations of the functional blocks of the Boundary-Scan implemented. Chapter 4 presents the layout process used based on the design developed on chapter 3, describing the software used for this purpose, the planning of the layout location (floorplan) and its dimensions, the layout of individual blocks, checks in terms of layout rules, the comparison with the final design and finally the simulation. Chapter 5 describes how the functional tests were performed to verify the design compliancy with the specifications of Standard IEEE 1149.1. These tests were focused on the application of signals to input and output ports of the produced prototype. Chapter 6 presents the conclusions that were taken throughout the execution of the work.Universidade da Madeir

Custos e benefícios da formação na construção civil

Monografia apresentada à Universidade Fernando Pessoa como parte dos requisitos para a obtenção do grau de licenciado em Engenharia do CivilSendo Portugal um país fortemente marcado por baixos níveis de Formação Profissional na Construção Civil, a Formação Profissional apresenta-se como uma ferramenta primordial, para suprimir esta lacuna neste sector. Muito se tem feito e muito há ainda a fazer para que se consiga a resolução de graves problemas que afectam o sector desde início. O presente trabalho pretende essencialmente abordar os Custos e Benefícios da Formação Profissional, no sector da Construção Civil, estando dividido por três capítulos. A primeira parte deste trabalho centra-se na Formação Profissional para todos. Começa-se por uma definição do conceito, passando, posteriormente, para as modalidades de formação existentes em Portugal, englobando todos os níveis de escolaridade e para todos os sectores de actividade. No segundo capítulo é feita uma caracterização socioeconómica do sector da Construção Civil, em Portugal, dando sempre ênfase à Formação Profissional, apresentando-se também alguns indicadores desta conjuntura e da mais-valia da Formação Profissional neste sector, em face da desejada relação existente com a sinistralidade laboral. No último capítulo realizou-se um estudo de caso, tendo sido simulado uma situação, em contexto real de trabalho, numa empresa de construção civil. Foi considerado a organização de acções de formação, com o objectivo de aumentar as qualificações dos colaboradores da empresa. Quantificaram-se todos os custos da realização das ditas acções de formação, bem como todos os benefícios em “valores monetários”, permitindo assim a realização de um estudo custo/benefício.Being Portugal a country where in Construction field, just a few workers have done some Professional Training; these trainings have an important play on the success of a construction company. A lot was already done in this field, however much more should be done in order to solve the problems that are present in the construction sector since the beginning. The main goal of this work is to study the benefits and cost of the professional training on the construction sector. This work is divided in three different chapters. In the first part, the work is focused on the professional training for all. It was started by defining the concept of professional training followed by the definition of the different training arrangements that exist in Portugal, where the different academic degrees are taken in account in the all different activities in the sector. In the second chapter the socioeconomic characterization in the Portuguese Construction sector was done, where the Professional training takes the rule. The importance of the professional training in the construction sector was presented, once that the professional training is connected to the existence or not of the sinistrality. A case study is deeply analyzed in the last chapter, it was simulated a real situation in a work environment inside a construction company. An organization of professional trainings was taken in account, because the qualification of the each worker is an objective to achieve. All the costs of the professional trainings were quantified followed by linking the trainings with the real benefits that were translated as “currency values”, in this way it was possible to make a benefit/cost study.N/

Segurança contra incêndio em estabelecimentos de restauração e bebidas

Tese de mestrado integrado. Engenharia Civil (Construções). Universidade do Porto. Faculdade de Engenharia. 201