XAdES4J: a java library for XAdES signature services

As comunicações electrónicas são cada vez mais o meio de eleição para negócios entre entidades e para as relações entre os cidadãos e o Estado (e-government). Esta diversidade de transacções envolve, muitas vezes, informação sensível e com possível valor legal. Neste contexto, as assinaturas electrónicas são uma importante base de confiança, fornecendo garantias de integridade e autenticação entre os intervenientes. A produção de uma assinatura digital resulta não só no valor da assinatura propriamente dita, mas também num conjunto de informação adicional acerca da mesma, como o algoritmo de assinatura, o certificado de validação ou a hora e local de produção. Num cenário heterogéneo como o descrito anteriormente, torna-se necessária uma forma flexível e interoperável de descrever esse tipo de informação. A linguagem XML é uma forma adequada de representar uma assinatura neste contexto, não só pela sua natureza estruturada, mas principalmente por ser baseada em texto e ter suporte generalizado. A recomendação XML Signature Syntax and Processing (ou apenas XML Signature) foi o primeiro passo na representação de assinaturas em XML. Nela são definidas sintaxe e regras de processamento para criar, representar e validar assinaturas digitais. As assinaturas XML podem ser aplicadas a qualquer tipo de conteúdos digitais identificáveis por um URI, tanto no mesmo documento XML que a assinatura, como noutra qualquer localização. Além disso, a mesma assinatura XML pode englobar vários recursos, mesmo de tipos diferentes (texto livre, imagens, XML, etc.). À medida que as assinaturas electrónicas foram ganhando relevância tornou-se evidente que a especificação XML Signature não era suficiente, nomeadamente por não dar garantias de validade a longo prazo nem de não repudiação. Esta situação foi agravada pelo facto da especificação não cumprir os requisitos da directiva 1999/93/EC da União Europeia, onde é estabelecido um quadro legal para as assinaturas electrónicas a nível comunitário. No seguimento desta directiva da União Europeia foi desenvolvida a especificação XML Advanced Electronic Signatures que define formatos XML e regras de processamento para assinaturas electrónicas não repudiáveis e com validade verificável durante períodos de tempo extensos, em conformidade com a directiva. Esta especificação estende a recomendação XML Signature, definindo novos elementos que contêm informação adicional acerca da assinatura e dos recursos assinados (propriedades qualificadoras). A plataforma Java inclui, desde a versão 1.6, uma API de alto nível para serviços de assinaturas digitais em XML, de acordo com a recomendação XML Signature. Contudo, não existe suporte para assinaturas avançadas. Com este projecto pretende-se desenvolver uma biblioteca Java para a criação e validação de assinaturas XAdES, preenchendo assim a lacuna existente na plataforma. A biblioteca desenvolvida disponibiliza uma interface com alto nível de abstracção, não tendo o programador que lidar directamente com a estrutura XML da assinatura nem com os detalhes do conteúdo das propriedades qualificadoras. São definidos tipos que representam os principais conceitos da assinatura, nomeadamente as propriedades qualificadoras e os recursos assinados, sendo os aspectos estruturais resolvidos internamente. Neste trabalho, a informação que compõe uma assinatura XAdES é dividia em dois grupos: o primeiro é formado por características do signatário e da assinatura, tais como a chave e as propriedades qualificadoras da assinatura. O segundo grupo é composto pelos recursos assinados e as correspondentes propriedades qualificadoras. Quando um signatário produz várias assinaturas em determinado contexto, o primeiro grupo de características será semelhante entre elas. Definiu-se o conjunto invariante de características da assinatura e do signatário como perfil de assinatura. O conceito é estendido à verificação de assinaturas englobando, neste caso, a informação a usar nesse processo, como por exemplo os certificados raiz em que o verificador confia. Numa outra perspectiva, um perfil constitui uma configuração do serviço de assinatura correspondente. O desenho e implementação da biblioteca estão também baseados no conceito de fornecedor de serviços. Um fornecedor de serviços é uma entidade que disponibiliza determinada informação ou serviço necessários à produção e verificação de assinaturas, nomeadamente: selecção de chave/certificado de assinatura, validação de certificados, interacção com servidores de time-stamp e geração de XML. Em vez de depender directamente da informação em causa, um perfil — e, consequentemente, a operação correspondente — é configurado com fornecedores de serviços que são invocados quando necessário. Para cada tipo de fornecedor de serviços é definida um interface, podendo as correspondentes implementações ser configuradas de forma independente. A biblioteca inclui implementações de todos os fornecedores de serviços, sendo algumas delas usadas for omissão na produção e verificação de assinaturas. Uma vez que o foco do projecto é a especificação XAdES, o processamento e estrutura relativos ao formato básico são delegados internamente na biblioteca Apache XML Security, que disponibiliza uma implementação da recomendação XML Signature. Para validar o funcionamento da biblioteca, nomeadamente em termos de interoperabilidade, procede-se, entre outros, à verificação de um conjunto de assinaturas produzidas por Estados Membros da União Europeia, bem como por outra implementação da especificação XAdES.

Sistemas de abastecimento de água e saneamento básico

O presente relatório de estágio enquadra-se no âmbito do Trabalho Final de Mestrado (TFM) do curso de Engenharia Civil, área de especialização de Hidráulica, do Instituto Superior de Engenharia de Lisboa, e baseia-se na temática dos sistemas de abastecimento de água e drenagem de águas residuais. O estágio, intitulado de “Sistemas de Abastecimento de Agua e Saneamento Básico”, decorreu numa empresa de consultaria de engenharia denominada ENGIDRO – Estudos de Engenharia, Lda., vocacionada para a realização de estudos e projectos na área de Hidráulica, com particular incidência na Hidráulica Urbana e Saneamento Básico. O estágio iniciou-se com um adequado enquadramento profissional na empresa e incidiu principalmente no desenvolvimento de trabalhos de concepção e dimensionamento, a nível de projectos de execução, de sistemas de abastecimento de água e de saneamento básico, para 21 localidades da província de Lunda Sul, em Angola, com prestação de serviços para o Governo Provincial de Lunda Sul – Direcção Provincial da Energia e Aguas, juntamente com empresa CENGA – Consultores de Engenharia de Angola, S.A. Na prestação de serviços à entidade contratante foram efectuados trabalhos de campo, que consistiram principalmente em reconhecimentos do terreno, levantamentos topográficos e recolha de informação relevante sobre elementos condicionantes dos projectos (origens e disponibilidades de água, natureza e declive dos terrenos, tipos de infra-estruturas locais) e trabalhos de gabinete para compilação e análise da informação recolhida na elaboração dos projectos de execução, incluindo pecas desenhadas (desenhos pormenorizados) e peças escritas (memórias descritivas e justificativas, medições e orçamentos). Sendo os projectos destinados a aglomerados populacionais pouco desenvolvidos e com carências e condicionantes de diversa ordem (falta de energia eléctrica, de acessos, de telecomunicações, de meios técnicos e materiais, entre outros), prestou-se especial atenção aos aspectos da concepção, privilegiando soluções de baixa tecnologia, mais fáceis de explorar e manter com os recursos locais disponíveis.

Palaeomagnetism, rock magnetism and AMS of the Cabo Magmatic Province, NE Brazil, and the opening of South Atlantic

P>Reconstruction of the South Atlantic opening has long been a matter of debate and several models have been proposed. One problem in tracing properly the Atlantic history arises from the existence of a long interval without geomagnetic reversals, the Cretaceous Normal Superchron, for which ages are difficult to assign. Palaeomagnetism may help in addressing this issue if high-quality palaeomagnetic poles are available for the two drifting continental blocks, and if precise absolute ages are available. In this work we have investigated the Cabo Magmatic Province, northeastern Brazil, recently dated at 102 +/- 1 Ma (zircon fission tracks, Ar39/Ar40). All volcanic and plutonic rocks showed stable thermal and AF demagnetization patterns, and exhibit primary magnetic signatures. AMS data also support a primary origin for the magnetic fabric and is interpreted to be contemporaneous of the rock formation. The obtained pole is located at 335.9 degrees E/87.9 degrees S (N = 24; A(95) = 2.5; K = 138) and satisfies modern quality criteria, resulting in a reference pole for South America at similar to 100 Ma. This new pole also gives an insight to test and discuss the kinematic models currently proposed for the South Atlantic opening during mid-Cretaceous.

Energy and ancillary services joint market simulation

In order to develop a flexible simulator, a variety of models for Ancillary Services (AS) negotiation has been implemented in MASCEM – a multi-agent system competitive electricity markets simulator. In some of these models, the energy and the AS are addressed simultaneously while in other models they are addressed separately. This paper presents an energy and ancillary services joint market simulation. This paper proposes a deterministic approach for solving the energy and ancillary services joint market. A case study based on the dispatch of Regulation Down, Regulation Up, Spinning Reserve, and Non-Spinning Reserve services is used to demonstrate that the use of the developed methodology is suitable for solving this kind of optimization problem. The presented case study is based on CAISO real AS market data considers fifteen bids.

Shiftworking families: parents' working schedule and sleep patterns of adolescents attending school in two shifts

OBJECTIVE: To explore whether parents' engagement in shift work affects the sleep habits of their adolescent children who attend school in two shifts. METHODS: The data were drawn from an extensive survey of sleep and daytime functioning of adolescents attending school one week in the morning and the other in the afternoon. The participants were 1,386 elementary and high school students (11-18 years old) whose parents were both employed. The data were analyzed using MANOVA, with parents' work schedule, adolescents' gender and type of school as between-subject factors. RESULTS: Parents' working schedule significantly affected the sleep patterns of high school adolescents. When attending school in the morning, adolescents whose parents were both day workers woke up somewhat later than adolescents with one shiftworking parent. In addition, they slept longer than adolescents whose parents were both shift workers. On weekends, adolescents whose parents both worked during the day went to bed earlier than adolescents whose parents were both shiftworkers. They also had smaller bedtime delay on weekends with respect to both morning and afternoon shifts than adolescents for whom one or both parents worked shifts. A significant interaction between parents' working schedule, adolescents' gender and type of school was found for sleep extension on weekends after afternoon shift school. CONCLUSIONS: Parental involvement in shift work has negative effects on the sleep of high school adolescents. It contributes to earlier wake-up time and shorter sleep in a week when adolescents attend school in the morning, as well as to greater bedtime irregularity.

Comparison between deterministic and meta-heuristic methods applied to ancillary services dispatch

This paper proposes two meta-heuristics (Genetic Algorithm and Evolutionary Particle Swarm Optimization) for solving a 15 bid-based case of Ancillary Services Dispatch in an Electricity Market. A Linear Programming approach is also included for comparison purposes. A test case based on the dispatch of Regulation Down, Regulation Up, Spinning Reserve and Non-Spinning Reserve services is used to demonstrate that the use of meta-heuristics is suitable for solving this kind of optimization problem. Faster execution times and lower computational resources requirements are the most relevant advantages of the used meta-heuristics when compared with the Linear Programming approach.

ANN based day-ahead ancillary services forecast for electricity market simulation

Adequate decision support tools are required by electricity market players operating in a liberalized environment, allowing them to consider all the business opportunities and take strategic decisions. Ancillary services (AS) represent a good negotiation opportunity that must be considered by market players. Based on the ancillary services forecasting, market participants can use strategic bidding for day-ahead ancillary services markets. For this reason, ancillary services market simulation is being included in MASCEM, a multi-agent based electricity market simulator that can be used by market players to test and enhance their bidding strategies. The paper presents the methodology used to undertake ancillary services forecasting, based on an Artificial Neural Network (ANN) approach. ANNs are used to day-ahead prediction of non-spinning reserve (NS), regulation-up (RU), and regulation down (RD). Spinning reserve (SR) is mentioned as past work for comparative analysis. A case study based on California ISO (CAISO) data is included; the forecasted results are presented and compared with CAISO published forecast.

Ancillary services market clearing simulation: a comparison between deterministic and heuristic methods

Electricity market players operating in a liberalized environment requires access to an adequate decision support tool, allowing them to consider all the business opportunities and take strategic decisions. Ancillary services represent a good negotiation opportunity that must be considered by market players. For this, decision support tool must include ancillary market simulation. This paper proposes two different methods (Linear Programming and Genetic Algorithm approaches) for ancillary services dispatch. The methodologies are implemented in MASCEM, a multi-agent based electricity market simulator. A test case based on California Independent System Operator (CAISO) data concerning the dispatch of Regulation Down, Regulation Up, Spinning Reserve and Non-Spinning Reserve services is included in this paper.

Ancillary services dispatch using linear programming and genetic algorithm approaches

Electricity market players operating in a liberalized environment requires access to an adequate decision support tool, allowing them to consider all the business opportunities and take strategic decisions. Ancillary services represent a good negotiation opportunity that must be considered by market players. For this, decision support tools must include ancillary market simulation. This paper proposes two different methods (Linear Programming and Genetic Algorithm approaches) for ancillary services dispatch. The methodologies are implemented in MASCEM, a multi-agent based electricity market simulator. A test case concerning the dispatch of Regulation Down, Regulation Up, Spinning Reserve and Non-Spinning Reserve services is included in this paper.

Cancer incidence projections for Lisbon and Santarém districts: an aid to radiotherapy services planning

Will the existing means in Radiotherapy respond to the needs of the potential user population in 2014 for Lisbon and Santarém districts? Number of treatment units? Number of Radiotherapy Technologists? Temporal variations of the dimension and age structure of the populations: Coastal areas/Interior areas, Urban areas/Rural areas. Temporal variations in the incidence of several types of cancer. Overall objectives: evaluate of the necessities of Radiotherapy for Lisbon and Santarém districts in 2014 and elaboration of proposals that aim the access/use for the potential user population.

Early patterns of recovery from disturbance in intertidal algal assemblages: consistency across regions within a marine province

The importance of disturbance and the subsequent rate and pattern of recovery has been long recognised as an important driver of community structure. Community recovery is affected by processes operating at local and regional scales yet the examination of community level responses to a standardised disturbance at regional scales (i.e. among regions under different environmental conditions) has seldom been attempted. Here, we mechanically disturbed rocky intertidal lower shore algal dominated assemblages at three locations within each of three different regions within the Lusitanian biogeographical province (Azores, northern Portugal and the Canary Islands). All organisms were cleared from experimental plots and succession followed over a period of 12 months at which time we formally compared the assemblage structure to that of unmanipulated controls. Early patterns of recovery of disturbed communities varied among regions and was positively influenced by temperature, but not by regional species richness. Different components of the assemblage responded differently to disturbance. Regional differences in the relative abundance and identity of species had a key influence on the overall assemblage recovery. This study highlights how regional-scales differences in environmental conditions and species pool are important determinants of recovery of disturbed communities.

Qualidade de vida das famílias apoiadas por intervenção precoce: identificação de fatores mais valorizados pelas famílias

Dissertação apresentada à Escola Superior de Educação de Lisboa para obtenção do grau de mestre em Intervenção Precoce

Representações sobre a creche dos pais de crianças que frequentam a creche e dos pais que optaram por outro cuidado

Dissertação apresentada na Escola Superior de Educação de Lisboa, para obtenção do grau de Mestre em Ciências da Educação - Especialidade Intervenção Precoce

Neonatal mortality: description and effect of hospital of birth after risk adjustment

OBJECTIVE: To assess the effect of hospital of birth on neonatal mortality. METHODS: A birth cohort study was carried out in Pelotas, Southern Brazil, in 2004. All hospital births were assessed by daily visits to all maternity hospitals and 4558 deliveries were included in the study. Mothers were interviewed regarding potential risk factors. Deaths were monitored through regular visits to hospitals, cemeteries and register offices. Two independent pediatricians established the underlying cause of death based on information obtained from medical records and home visits to parents. Logistic regression was used to estimate the effect of hospital of birth, controlling for confounders related to maternal and newborn characteristics, according to a conceptual model. RESULTS: Neonatal mortality rate was 12.7‰ and it was highly influenced by birthweight, gestational age, and socioeconomic variables. Immaturity was responsible for 65% of neonatal deaths, followed by congenital anomalies, infections and intrapartum asphyxia. Adjusting for maternal characteristics, a three-fold increase in neonatal mortality was seen between similar complexity hospitals. The effect of hospital remained, though lower, after controlling for newborn characteristics. CONCLUSIONS: Neonatal mortality was high, mainly related to immaturity, and varied significantly across maternity hospitals. Further investigations comparing delivery care practices across hospitals are needed to better understand NMR variation and to develop strategies for neonatal mortality reduction.

Knowledge, attitude and practice of mammography among women users of public health services

OBJECTIVE: To evaluate knowledge, attitude and practice related to mammography among women users of local health services, identifying barriers to its performance. METHODS: A total of 663 women were interviewed at 13 local health centers in a city of Southeastern Brazil, in 2001. Interviewees were randomly selected at each center and they were representative from different socioeconomic conditions. The number of interviewees at each center was proportional to monthly mean appointments. For data analysis, answers were described as knowledge, attitude, practice and their respective adequacies and then they were correlated with control variables through the chi-square test. RESULTS: Only 7.4% of the interviewees had adequate knowledge on mammography, while 97.1% of women had an adequate attitude. The same was seen for the practice of mammography that was adequate in 35.7% of the cases. The main barrier to mammography was lack of referral by physicians working at the health center (81.8%). There was an association between adequacy of attitude and five years or more of education and being married. There was also an association between adequacy of mammography practice and being employed and family income up to four minimum wages. CONCLUSIONS: Women users of local health services had no adequate knowledge and practice related to mammography despite having an adequate attitude about this exam.