Real Time Internet DGPS Service

The accuracy of the Navigation Satellite Timing and Ranging (NAVSTAR) Global Positioning System (GPS) measurements is insufficient for many outdoor navigation tasks. As a result, in the late nineties, a new methodology ��� the Differential GPS (DGPS) ��� was developed. The differential approach is based on the calculation and dissemination of the range errors of the GPS satellites received. GPS/DGPS receivers correlate the broadcasted GPS data with the DGPS corrections, granting users increased accuracy. DGPS data can be disseminated using terrestrial radio beacons, satellites and, more recently, the Internet. Our goal is to provide mobile platforms within our campus with DGPS data for precise outdoor navigation. To achieve this objective, we designed and implemented a three-tier client/server distributed system that establishes Internet links with remote DGPS sources and performs campus-wide dissemination of the obtained data. The Internet links are established between data servers connected to remote DGPS sources and the client, which is the data input module of the campus-wide DGPS data provider. The campus DGPS data provider allows the establishment of both Intranet and wireless links within the campus. This distributed system is expected to provide adequate support for accurate (submetric) outdoor navigation tasks.

Implementation of a Campus wide DGPS Data Server

Although the Navigation Satellite Timing and Ranging (NAVSTAR) Global Positioning System (GPS) is, de facto, the standard positioning system used in outdoor navigation, it does not provide, per se, all the features required to perform many outdoor navigational tasks. The accuracy of the GPS measurements is the most critical issue. The quest for higher position readings accuracy led to the development, in the late nineties, of the Differential Global Positioning System (DGPS). The differential GPS method detects the range errors of the GPS satellites received and broadcasts them. The DGPS/GPS receivers correlate the DGPS data with the GPS satellite data they are receiving, granting users increased accuracy. DGPS data is broadcasted using terrestrial radio beacons, satellites and, more recently, the Internet. Our goal is to have access, within the ISEP campus, to DGPS correction data. To achieve this objective we designed and implemented a distributed system composed of two main modules which are interconnected: a distributed application responsible for the establishment of the data link over the Internet between the remote DGPS stations and the campus, and the campus-wide DGPS data server application. The DGPS data Internet link is provided by a two-tier client/server distributed application where the server-side is connected to the DGPS station and the client-side is located at the campus. The second unit, the campus DGPS data server application, diffuses DGPS data received at the campus via the Intranet and via a wireless data link. The wireless broadcast is intended for DGPS/GPS portable receivers equipped with an air interface and the Intranet link is provided for DGPS/GPS receivers with just a RS232 DGPS data interface. While the DGPS data Internet link servers receive the DGPS data from the DGPS base stations and forward it to the DGPS data Internet link client, the DGPS data Internet link client outputs the received DGPS data to the campus DGPS data server application. The distributed system is expected to provide adequate support for accurate (sub-metric) outdoor campus navigation tasks. This paper describes in detail the overall distributed application.

Laser welding of shape memory alloys

Disserta����o apresentada na Faculdade de Ci��ncias e Tecnologia da Universidade Nova de Lisboa para obten����o do grau de Mestre em Engenharia Mec��nica

TERT Promoter Mutations Are a Major Indicator of Poor Outcome in Differentiated Thyroid Carcinomas

Context: Telomerase promoter mutations (TERT) were recently described in follicular cell-derived thyroid carcinomas (FCDTC) and seem to be more prevalent in aggressive cancers. Objectives: We aimed to evaluate the frequency of TERT promoter mutations in thyroid lesions and to investigate the prognostic significance of such mutations in a large cohort of patients with differentiated thyroid carcinomas (DTCs). Design: This was a retrospective observational study. Setting and Patients: We studied 647 tumors and tumor-like lesions. A total of 469 patients with FCDTC treated and followed in five university hospitals were included. Mean follow-up (��SD) was 7.8 �� 5.8 years. Main Outcome Measures: Predictive value of TERT promoter mutations for distant metastasization, disease persistence at the end of follow-up, and disease-specific mortality. Results: TERT promoter mutations were found in 7.5% of papillary carcinomas (PTCs), 17.1% of follicular carcinomas, 29.0% of poorly differentiated carcinomas, and 33.3% of anaplastic thyroid carcinomas. Patients with TERT-mutated tumors were older (P < .001) and had larger tumors (P = .002). In DTCs, TERT promoter mutations were significantly associated with distant metastases (P < .001) and higher stage (P < .001). Patients with DTC harboring TERT promoter mutations were submitted to more radioiodine treatments (P = .009) with higher cumulative dose (P = .004) and to more treatment modalities (P = .001). At the end of follow-up, patients with TERT-mutated DTCs were more prone to have persistent disease (P = .001). TERT promoter mutations were significantly associated with disease-specific mortality [in the whole FCDTC (P < .001)] in DTCs (P < .001), PTCs (P = .001), and follicular carcinomas (P < .001). After adjusting for age at diagnosis and gender, the hazard ratio was 10.35 (95% confidence interval 2.01���53.24; P = .005) in DTC and 23.81 (95% confidence interval 1.36���415.76; P = .03) in PTCs. Conclusions: TERT promoter mutations are an indicator of clinically aggressive tumors, being correlated with worse outcome and disease-specific mortality in DTC. TERT promoter mutations have an independent prognostic value in DTC and, notably, in PTC.

Relat��rio de est��gio

Relat��rio de Est��gio apresentado �� Faculdade de Ci��ncias e Tecnologia da Universidade Nova de Lisboa, nos termos estabelecidos no Regulamento do Mestrado em Ensino da Matem��tica, para a obten����o do Grau de Mestre em Ensino de Matem��tica no 3�� ciclo do Ensino B��sico e no Secund��rio

Robot visual localization through local feature fusion: an evaluation of multiple classifiers combination approaches

In the last decade, local image features have been widely used in robot visual localization. In order to assess image similarity, a strategy exploiting these features compares raw descriptors extracted from the current image with those in the models of places. This paper addresses the ensuing step in this process, where a combining function must be used to aggregate results and assign each place a score. Casting the problem in the multiple classifier systems framework, in this paper we compare several candidate combiners with respect to their performance in the visual localization task. For this evaluation, we selected the most popular methods in the class of non-trained combiners, namely the sum rule and product rule. A deeper insight into the potential of these combiners is provided through a discriminativity analysis involving the algebraic rules and two extensions of these methods: the threshold, as well as the weighted modifications. In addition, a voting method, previously used in robot visual localization, is assessed. Furthermore, we address the process of constructing a model of the environment by describing how the model granularity impacts upon performance. All combiners are tested on a visual localization task, carried out on a public dataset. It is experimentally demonstrated that the sum rule extensions globally achieve the best performance, confirming the general agreement on the robustness of this rule in other classification problems. The voting method, whilst competitive with the product rule in its standard form, is shown to be outperformed by its modified versions.

Projecto de sistema de fixa����o de pun����es para quinadoras hidr��ulicas

Mestrado em Engenharia Mec��nica - Constru����es Mec��nicas

Estudo da influ��ncia de vari��veis do processo de corte em ���wafers��� para semicondutores nas avarias el��ctricas devidas a ���curling���

Mestrado em Engenharia Mec��nica - Materiais e Tecnologias de Fabrico

Educating for earthquake science and risk in a tectonically slowly deforming region

Over the past decade, scientists have been called to participate more actively in public education and outreach (E&O). This is particularly true in fields of significant societal impact, such as earthquake science. Local earthquake risk culture plays a role in the way that the public engages in educational efforts. In this article, we describe an adapted E&O program for earthquake science and risk. The program is tailored for a region of slow tectonic deformation, where large earthquakes are extreme events that occur with long return periods. The adapted program has two main goals: (1) to increase the awareness and preparedness of the population to earthquake and related risks (tsunami, liquefaction, fires, etc.), and (2) to increase the quality of earthquake science education, so as to attract talented students to geosciences. Our integrated program relies on activities tuned for different population groups who have different interests and abilities, namely young children, teenagers, young adults, and professionals.

A conserva����o material e documental da obra ���Instala����o191093,parte1��� de Francisco Rocha

Disserta����o apresentada na Faculdade de Ci��ncias e Tecnologia para obten����o do grau de Mestre em Conserva����o e Restauro

O centro de arte colec����o Manuel de Brito - G��nese, desenvolvimento e perspectivas de crescimento da institui����o

Disserta����o apresentada para cumprimento dos requisitos necess��rios �� obten����o do grau de Mestre em Museologia

Entamoeba histolytica: fecal antigen capture immunoassay for the diagnosis of enteric amebiasis by a monoclonal antibody

Amebiasis continues to be of epidemiological importance in underdeveloped countries. Clinical diagnosis and epidemiological setting in a region are based on the fecal microscopic identification of cysts or trophozoites. This procedure requires well trained personnel, is laborious, of low sensitivity and frequently yields false-positives results. The present study was designed to develop an immuno-enzymatic fecal 96 kDa antigen capture test (COPROELISA-Eh) more sensitive and specific than microscopic diagnosis of amebiasis. Triplicates of 177 stool samples processed by the formol-ether concentration method, were defined as positive or negative by three experienced microscopic observers. Another aliquot was submitted to the antigen capture test by a monoclonal antibody against a specific membrane antigen of pathogenic strains of Entamoeba histolytica. Optical densities were interpreted as positive when they exceeded the mean value of negative samples plus two standard deviations. COPROELISA-Eh showed a 94.4% sensitivity, 98.3% specificity, 96.2% positive predictive value and 97.6% negative predictive value for the detection of E. histolytica in feces. COPROELISA-Eh is more sensitive and specific than microscopic examination, does not require specially trained personnel and allows the simultaneous processing of a large number of samples.

Fundamentos hist��ricos da poesia luso-��rabe (no s��culo de almut��mide) na nova m��sica portuguesa o amor e o vinho

Disserta����o apresentada para cumprimento dos requisitos necess��rios �� obten����o do grau de Doutor em Hist��ria Cultural e das Mentalidades Contempor��neas

A tipografia como forma de express��o aut��noma

Trabalho de Projecto apresentado para cumprimento dos requisitos necess��rios �� obten����o do grau de Mestre em Novos Media e Pr��ticas Web

Desenvolvimento de sistema de apoio din��mico da chapa no corte em guilhotina

Guilhotinas s��o m��quinas robustas, de corte rectil��neo, normalmente associadas a equipamentos de baixo custo, devido �� pequena quantidade de dispositivos tecnol��gicos incorporados. No entanto, esta situa����o pode ser alterada atrav��s da criatividade dos projetistas deste tipo de equipamento. Analisando algumas opera����es espec��ficas, pode-se observar que algumas ferramentas, quando associadas ao equipamento, podem aumentar substancialmente a produtividade do processo de corte e a qualidade do produto final. Em rela����o ao processo de corte de chapas finas de metal, pode-se observar que na fase final de corte, o peso do material a cortar �� suspenso por uma pequena por����o de material que ainda n��o foi sujeita ao corte. Este facto leva a uma deforma����o pl��stica nesta ��ltima zona, causando problemas de qualidade no produto final, que n��o ficar�� completamente plano. Este trabalho foi desenvolvido em torno deste problema, estudando a melhor solu����o para desenvolver uma nova ferramenta, capaz de evitar a falta de nivelamento da placa, ap��s corte. Um novo equipamento foi concebido, capaz de ser facilmente incorporado na guilhotina, permitindo o acompanhamento da inclina����o da l��mina durante a opera����o de corte. O sistema �� totalmente automatizado, sendo operado por uma ��nica instru����o de corte dada pelo operador da m��quina. Este sistema permite �� empresa fabricante aumentar o valor agregado de cada m��quina, oferecendo aos clientes solu����es avan��adas, contribuindo desta forma para a sustentabilidade do neg��cio da empresa.