Identification of PEM fuel cells based on support vector regression and orthonormal bases

© 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Polymer Electrolyte Membrane Fuel Cells (PEMFC) are efficient devices that convert the chemical energy of the reactants in electricity. In this type of fuel cells, the performance of the air supply system is fundamental to improve their efficiency. An accurate mathematical model representing the air filling dynamics for a wide range of operating points is then necessary for control design and analysis. In this paper, a new Wiener model identification method based on Support Vector (SV) Regression and orthonormal bases is introduced and used to estimate a nonlinear dynamical model for the air supply system of a laboratory PEMFC from experimental data. The method is experimentally validated using a PEMFC system based on a ZB 8-cell stack with Nafion 115 membrane electrode assembliesPeer ReviewedPostprint (author's final draft

O papel do examinador experiente no diagnóstico colposcópico em mulheres com céllulas atípicas de significado indeterminado quando não se pode afastar lesão intraepitelial de alto grau (ASC-H)

Orientadora : Profa. Dra. Rita Maira ZanineDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências da Saúde, Programa de Pós-Graduação em Tocoginecologia. Defesa : Curitiba, 28/04/2017Inclui referências : f. 72-81Resumo: INTRODUÇÃO: O câncer de colo de útero é a segunda neoplasia que mais acomete a mulher no mundo, possui história natural longa iniciada em lesões precursoras que se devidamente diagnosticadas e tratadas, levam a expressiva redução da morbimortalidade pela doença. O rastreio dessas lesões precursoras é feito pelo uso da citologia oncótica, enquanto o correto diagnóstico das mesmas é dado pela impressão colposcópica. O resultado citológico Atipias de Células Escamosas Quando não se pode Afastar Lesão de Alto Grau (ASC-H) está associado ao diagnóstico de Lesão Intraepitelial de Alto Grau/ High-Grade Squamous Intraepithelial Lesion (HSIL) ou Câncer em uma frequência suficientemente alta para justificar e indicação imediata ao exame colposcópico. OBJETIVO: Analisar a acurácia dos achados colposcópicos no diagnóstico das mulheres com ASC-H. PACIENTES E MÉTODOS: Foram selecionadas 106 mulheres com resultado citológico definido como ASC-H, confirmado após revisão cegada por dois patologistas experientes. Todas as mulheres foram submetidas ao exame colposcópico sob supervisão direta da mesma colposcopista. As pacientes com diagnóstico NIC 2 ou mais foram submetidas a Exérese da Zona de Transformação (EZT). As mulheres com impressão colposcópica negativa ou menor foram colocadas em seguimento clínico semestral até dois seguimentos negativos, quando isso não ocorreu foram igualmente submetidas a EZT. Dos prontuários médicos foram coletados dados referentes a impressão colposcópica, variáveis sociodemográficas, resultado do seguimento clínico e das peças anatomopatológicas. RESULTADO: Das 106 pacientes, 102 completaram o acompanhamento. A prevalência de NIC 2 ou mais foi de 63,7%. A impressão colposcópica obteve, em o seu achado maior uma sensibilidade de 91,67% IC 95%(0,8161 a 0,9724) especificidade de 93,1% com IC 95% (0,772 a 0,991) Valor Preditivo Positivo de 96,49% Valor Preditivo Negativo de 84,38% e acurácia de 92% para o diagnóstico de NIC 2 ou mais. Dos achados colposcópicos o que apresentou maior relevância foi a densidade de acetobranqueamento, seguido pelo pontilhado e mosaico grosseiros. A Zona de Transformação tipo 3 esteve menos correlacionada ao desfecho NIC 2 ou mais e não comprometeu a acurácia da colposcopia. Os achados demográficos não alcançaram significância estatística, entretanto, história pregressa de lesão intraepitelial e menopausa obtiveram p valor limítrofe de 0,085 e 0,072 respectivamente. CONCLUSÕES: Na população de estudo, a acurácia da colposcopia em estabelecer o diagnóstico para as pacientes referenciadas por citologia ASC-H foi de 92%, sendo que o achado colposcópico mais relevante quanto a presença de NIC 2 ou mais foi a densidade de acetobranqueamento. Palavras chave: Colposcopia e Câncer de Colo de Útero.Abstract: BACKGROUND: Cervical cancer is the seccond most frequent neoplasm of women in the world. It has a long natural history initiated in precursor lesions that, if properly diagnosed and treated, lead to an expressive reduction of morbidity and mortality due to the disease. The screening of these precursor lesions is done by the use of cervical cytology, while the correct diagnosis of them is given by the colposcopic impression. The cytological result atypical squamous cells cannot exclude high-grade squamous intraepithelial lesion (ASC-H) is highly associated with the diagnosis of high-grade squamous intraepithelial lesion (HSIL) or cervical cancer, that justifies prompt indication of colposcopic examination. OBJECTIVE: To analyze the accuracy of colposcopic findings in the diagnosis of ASC-H in a risk population. PATIENTS AND METHODS: We selected 106 patients with outcome defined as ASC-H after a blinded review by two experienced pathologists. They had undergone colposcopic examination under direct supervision of the same colposcopist. Patients with a CIN 2 or greater diagnosis were submitted to Excision of the Transformation Zone (ETZ), patients with negative or minor colposcopic impression were placed in a semi-annual clinical follow-up until two negative follow-ups were achieved, when this was not observed, they were also submitted to ETZ. From the medical records, were collected data on colposcopic impression, sociodemographic variables, result of clinical follow-up and pathological result. RESULTS: Of the 106 patients, 102 completed follow-up. The prevalence of CIN 2 or more was 63.7%. The major colposcopic impression obtained sensitivity of 91,67% CI95%(0,8161 to 0,9724), specificity 93,1% CI95%(0,772 to 0,991) Positive Predictive Value of 96,49%, Negative Predictive Value of 84,38% and accuracy of 92% for the diagnosis of CIN 2 or worse. Of the colposcopic findings, what has presented with greater relevance was the acetowhitening density, followed by coarse punctation and mosaic. The Type 3 Transformation Zone was less frequently associated with CIN 2 or worse diagnosis and did not compromise the accuracy of colposcopy. The demographic findings did not reach statistical significance, however, previous history of cervical intraepithelial neoplasia and menopause obtained a borderline value of 0,085 and 0,072 respectively. CONCLUSIONS: In the study population, the accuracy of colposcopy to establish the diagnosis for patients referred by ASC-H cytology was 92%, and the most relevant colposcopic finding regarding the presence of CIN 2 or more was the acetowhite density. Key Words: Colposcopy and Cervical Cance

Técnicas construtivas dos muros de pedra seca no algarve caracterização, implicações na sustentabilidade e mitigação de riscos naturais

Esta dissertação propõe uma reflexão a importância do património rural de muros de pedras seca na região algarvia, optou-se para um estudo de 8 meses em campo com levantamento fotográfico a verificar a localização, função, material e técnicas construtivas utilizadas nos muros encontrados nas três regiões algarvias, Serra, Barrocal e Litoral. Foi-se verificado a maior quantidade de muros na região do Barrocal e na faixa entre o Barrocal e o Litoral, devido suas vertentes, enquanto na Serra foram encontrados próximos de vilas, o Litoral apresentou muros em sua maioria de divisão de propriedade, raros os casos de muros de contenção. Os muros encontrados foram catalogados e subdivididos com relação a sua disposição estrutural no terreno, ao seu coroamento, acesso aos muros e aparelhamento, além das técnicas construtivas e sistema de regulação hídrica, apresentando também informações do seu contributo para as mitigações de riscos naturais, nomeadamente controle de erosão, redução da velocidade de escoamento da água da chuva e barreiras naturais em incêndios florestais. Durante a pesquisa houve algumas limitações, sobretudo ao encontro dos muros, primeiramente foi feito um estudo on-line com a ajuda do Google Maps para encontrar campos onde percebia-se um aglomerado de muros, no entanto, muitos encontravam-se abandonados, ou tomados pela vegetação, o que dificultou a sua catalogação para o projeto. A dissertação fornece informações sobre os efeitos sustentáveis dos muros nas regiões em que são encontrados, as existências de tais construções contam uma história dos antepassados agricultores que por ali desenvolveram técnicas para adaptar-se as condições topográficas, em que transformaram a paisagem natural de vertentes em terras aráveis próprias para a produção, contribuindo assim não só pela sustentabilidade social como também econômica.This dissertation proposes a reflection on the importance of the rural heritage of dry stone walls in the Algarve region, an 8-month field study was chosen with a photographic survey to verify the location, function, material and construction techniques used in the walls found in the three Algarve, Serra, Barrocal and Litoral regions. The largest amount of walls was found in the Barrocal region and in the range between the Barrocal and the Litoral, due to their slopes, while in the Serra they were found near villages, the Litoral had walls mostly of property division, rare. cases of retaining walls. The walls found were cataloged and subdivided in relation to their structural arrangement on the ground, their crowning, access to the walls and rigging, in addition to the construction techniques and water regulation system, also presenting information on their contribution to the mitigation of natural risks, namely erosion control, reduction of rainwater runoff speed and natural barriers in forest fires. During the research there were some limitations, especially in relation to the walls, first an online study was carried out with the help of Google Maps to find fields where a cluster of walls was perceived, however, many were found abandoned or taken by vegetation, which made its cataloging difficult for the project. The dissertation provides information about the sustainable effects of the walls in the regions where they are found, the existence of such constructions tells a story of the ancestors of farmers who developed techniques there to adapt to the topographical conditions, in which they transformed the natural landscape from slopes into arable land suitable for production, thus contributing not only to social but also economic sustainability

Depth-multiplexing spectral domain OCT for full eye length imaging with a single modulation unit

Measuring the axial length of the eye is emerging as a crucial approach to measure progression and monitor management of myopia. The high cost of current swept-source OCT devices, the preferred method for such measurements, limits their broad use, especially in lower-income communities.While spectral domain (SD) OCT is a more affordable option, its limited imaging range falls short for full eye length measurement. Existing depth-multiplexing (DM) techniques for SD-OCT provide a workaround by capturing images at multiple depths within the eye. However, these methods typically require multiple light modulation units or detectors for simultaneous imaging across depths, adding complexity and cost. In response, we propose a novel DM-SD-OCT approach that utilizes a single light modulation unit for depth encoding. This innovative method facilitates the capture of images at multiple depths within the eye using a single line scan camera, with subsequent computational demixing. Our implementation of this system successfully enabled simultaneous acquisition and demixing of signals from three distinct depths within the eye. The system's effectiveness was demonstrated using a model eye, confirming its potential as a cost-effective solution for comprehensive eye length measurement in clinical myopia research

Drystone walls in the Algarve, Portugal. Characterization and interconnection with the geology and lithology

Drystone walls can be frequently observed along the Algarve, south region of Portugal, performing both support and property division. This region is also known by its geological diversity and, consequently, lithology, which are intimately related to the orography. The combination of all these factors allowed the proliferation of this traditional drystone walls during the last centuries, and they represent not only an important element of the landscape, but also a perspective of the social, economic and technical bases of Algarve’s heritage. This article intends to present this diversity and the relationship between its various facets. In order to achieve the objectives, several field surveys were carried out to different geological zones, with the intention of gathering information related to the natural material used and its construction technique, as well as interaction with local inhabitants. These visits were supported by bibliographic and “Web-graphic” research, to substantiate the hypotheses. Based on the data results it is possible to identify a close interconnection between the geology and wall structure typology, since they are made with the natural rock fragments (raw material) found nearby. However, its function is more related to the orogeny and lithology, the latter defining also the type of agricultural culture. The study is enriched by the enormous diversity of rock types, although the Algarve is a relatively small region. The main limitations found during the development of the study are related to the physical access to the walls and the interviews with the locals. These constrictions were due to the lack of land maintenance, allowing vegetation to growth naturally, invading and covering the walls, and also due to the pandemic situation brought by the COVID-19 virus, which interdict the interaction between persons and also the travels. Despite the restrictions mentioned, the fieldtrips gave enough data to support the correlation between the geology, lithology and the raw material used on the drystone walls, as well as their relation to the terraces that proliferate in specific areas of Algarve. In view of the scarcity of bibliographic elements associated with this subject, in the studied territory, the elaboration of documents that allow the identification, characterization, geo-location and dissemination of the object of study, is considered as an asset for this theme. Finally, the study aims to alert and counter the tendency to abandon this type of heritage, valuing it and making it known.info:eu-repo/semantics/publishedVersio

Análise dos métodos de avaliação de investimentos e opções de controle de Risco para projetos internos de TI em empresas de Tecnologia

O ambiente competitivo em que as empresas de tecnologia estão inseridas exige que estas se adaptem de forma rápida às mudanças, buscando opções que tragam flexibilidade para seus investimentos. Muitos modelos de avaliação de investimentos têm falhado em capturar o valor desta flexibilidade. Este trabalho apresenta uma análise dos modelos de avaliação de investimentos utilizados por empresas de tecnologia em seus projetos de TI. Para isto, realizou-se uma pesquisa Survey com 34 empresas situadas no estado do Rio Grande do Sul. Os principais resultados mostram que: (i) existe uma crescente exigência pela realização de análises de investimentos sempre que um investimento em TI é necessário; (ii) grande parte das empresas não realizam análises quantitativas de seus projetos; e (iii) as ações de contingência para os riscos estão desalinhadas ou subutilizadas se comparadas às alternativas propostas pela literatura. Isso oferece espaço para ganhos com métodos quantitativos que ofereçam maior flexibilidade, como é o caso de Opções Reais

Polarization sensitive optical frequency domain imaging system for endobronchial imaging

A polarization sensitive endoscopic optical frequency domain imaging (PS-OFDI) system with a motorized distal scanning catheter is demonstrated. It employs a passive polarization delay unit to multiplex two orthogonal probing polarization states in depth, and a polarization diverse detection unit to detect interference signal in two orthogonal polarization channels. Per depth location four electro-magnetic field components are measured that can be represented in a complex 2×2 field matrix. A Jones matrix of the sample is derived and the sample birefringence is extracted by eigenvalue decomposition. The condition of balanced detection and the polarization mode dispersion are quantified. A complex field averaging method based on the alignment of randomly pointing field phasors is developed to reduce speckle noise. The variation of the polarization states incident on the tissue due to the circular scanning and catheter sheath birefringence is investigated. With this system we demonstrated imaging of ex vivo chicken muscle, in vivo pig lung and ex vivo human lung specimens