939 resultados para Open Information Extraction
Resumo:
Com o crescimento da Internet como plataforma global para partilha de informação, cresceu também a diversidade de tipologias de informação a ser partilhada e consultada, nomeadamente informação geográfica. Neste âmbito surge como preocupação a interoperabilidade entre sistemas permitindo que sistemas diferentes possam “comunicar”, partilhando informações e recursos. O presente trabalho propõe-se recolher informação sobre a utilização das normas de interoperabilidade do Open Geospatial Consortium (OGC) na Administração Pública em Portugal, permitindo analisar e tirar conclusões relativamente a esta temática, tendo também em conta o seu enquadramento legal nacional.
Resumo:
A Internet possui inúmeros tipos de documentos e é uma influente fonte de informação.O conteúdo Web é projetado para os seres humanos interpretarem e não para as máquinas.Os sistemas de busca tradicionais são imprecisos na recuperação de informações. Ogoverno utiliza e disponibiliza documentos na Web para que os cidadãos e seus própriossetores organizacionais os utilizem, porém carece de ferramentas que apoiem na tarefa darecuperação desses documentos. Como exemplo, podemos citar a Plataforma de CurrículosLattes administrada pelo Cnpq.A Web semântica possui a finalidade de otimizar a recuperação dos documentos, ondeesses recebem significados, permitindo que tanto as pessoas quanto as máquinas possamcompreender o significado de uma informação. A falta de semântica em nossos documentos,resultam em pesquisas ineficazes, com informações divergentes e ambíguas. Aanotação semântica é o caminho para promover a semântica em documentos.O objetivo da dissertação é montar um arcabouço com os conceitos da Web Semânticaque possibilite anotar automaticamente o Currículo Lattes por meio de bases de dadosabertas (Linked Open Data), as quais armazenam o significado de termos e expressões.O problema da pesquisa está baseado em saber quais são os conceitos associados à WebSemântica que podem contribuir para a Anotação Semântica Automática do CurrículoLattes utilizando o Linked Open Data (LOD)?Na Revisão Sistemática da Literatura foi apresentado conceitos (anotação manual, automática,semi-automática, anotação intrusiva...), ferramentas (Extrator de Entidade...)e tecnologias (RDF, RDFa, SPARQL..) relativas ao tema. A aplicação desses conceitosoportunizou a criação do Sistema Lattes Web Semântico. O sistema possibilita a importaçãodo currículo XML da Plataforma Lattes, efetua a anotação automática dos dadosdisponibilizados utilizando as bases de dados abertas e possibilita efetuar consultas semânticas.A validação do sistema é realizada com a apresentação de currículos anotados e a realizaçãode consultas utilizando dados externos pertencentes ao LOD. Por fim é apresentado asconclusões, dificuldades encontradas e proposta de trabalhos futuros.
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This thesis discusses memory effects in open quantum systems with an emphasis on the Breuer, Laine, Piilo (BLP) measure of non-Markovianity. It is shown how the calculation of the measure can be simplifed and how quantum information protocols can bene t from memory e ects. The superdense coding protocol is used as an example of this. The quantum Zeno effect will also be studied from the point of view of memory e ects. Finally the geometric ideas used in simplifying the calculation of the BLP measure are applied in studying the amount of resources needed for detecting bipartite quantum correlations. It is shown that to decide without prior information if an unknown quantum state is entangled or not, an informationally complete measurement is required. The first part of the thesis contains an introduction to the theoretical ideas such as quantum states, closed and open quantum systems and necessary mathematical tools. The theory is then applied in the second part of the thesis as the results obtained in the original publications I-VI are presented and discussed.
Resumo:
Background: Digital forensics is a rapidly expanding field, due to the continuing advances in computer technology and increases in data stage capabilities of devices. However, the tools supporting digital forensics investigations have not kept pace with this evolution, often leaving the investigator to analyse large volumes of textual data and rely heavily on their own intuition and experience. Aim: This research proposes that given the ability of information visualisation to provide an end user with an intuitive way to rapidly analyse large volumes of complex data, such approached could be applied to digital forensics datasets. Such methods will be investigated; supported by a review of literature regarding the use of such techniques in other fields. The hypothesis of this research body is that by utilising exploratory information visualisation techniques in the form of a tool to support digital forensic investigations, gains in investigative effectiveness can be realised. Method:To test the hypothesis, this research examines three different case studies which look at different forms of information visualisation and their implementation with a digital forensic dataset. Two of these case studies take the form of prototype tools developed by the researcher, and one case study utilises a tool created by a third party research group. A pilot study by the researcher is conducted on these cases, with the strengths and weaknesses of each being drawn into the next case study. The culmination of these case studies is a prototype tool which was developed to resemble a timeline visualisation of the user behaviour on a device. This tool was subjected to an experiment involving a class of university digital forensics students who were given a number of questions about a synthetic digital forensic dataset. Approximately half were given the prototype tool, named Insight, to use, and the others given a common open-source tool. The assessed metrics included: how long the participants took to complete all tasks, how accurate their answers to the tasks were, and how easy the participants found the tasks to complete. They were also asked for their feedback at multiple points throughout the task. Results:The results showed that there was a statistically significant increase in accuracy for one of the six tasks for the participants using the Insight prototype tool. Participants also found completing two of the six tasks significantly easier when using the prototype tool. There were no statistically significant different difference between the completion times of both participant groups. There were no statistically significant differences in the accuracy of participant answers for five of the six tasks. Conclusions: The results from this body of research show that there is evidence to suggest that there is the potential for gains in investigative effectiveness when information visualisation techniques are applied to a digital forensic dataset. Specifically, in some scenarios, the investigator can draw conclusions which are more accurate than those drawn when using primarily textual tools. There is also evidence so suggest that the investigators found these conclusions to be reached significantly more easily when using a tool with a visual format. None of the scenarios led to the investigators being at a significant disadvantage in terms of accuracy or usability when using the prototype visual tool over the textual tool. It is noted that this research did not show that the use of information visualisation techniques leads to any statistically significant difference in the time taken to complete a digital forensics investigation.
Resumo:
GUEDES, Clediane de Araújo; FARIAS, Gabriela Belmont de. Information literacy: uma análise nas bibliotecas escolares da rede privada em Natal / RN. Revista Digital de Biblioteconomia e Ciência da Informação, Campinas, v. 4, n. 2, p. 110-133, jan./jun. 2007
Resumo:
The Open Journal project has completed its three year period of funding by the UK Electronic Libraries (eLib) programme (Rusbridge 1998). During that time, the number of journals that are available electronically leapt from a few tens to a few thousand. Some of these journals are now developing the sort of features the project has been advocating, in particular the use of links within journals, between different primary journals, with secondary journals data, and to non-journal sources. Assessing the achievements of the project and considering some of the difficulties it faced, we report on the different approaches to linking that the project developed, and summarise the important user responses that indicate what works and what does not. Looking ahead, there are signs of change, not just to simple linking within journals but to schemes in which links are the basis of "distributed" journals, where information may be shared and documents built from different sources. The significance has yet to be appreciated, but this would be a major change from printed journals. If projects such as this and others have provided the initial impetus, the motivation for distributed journals comes, perhaps surprisingly, from within certain parts of the industry, as the paper shows.
Resumo:
This is a long-term study of the use of information and communication technologies by 30 older adults (ages 70–97) living in a large retirement community. The study spanned the years of 1996 to 2008, during which time the research participants grappled with the challenges of computer use while aging 12 years. The researcher, herself a ‘mature learner,’ used a qualitative research design which included observations and open-ended interviews. Using a strategy of “intermittent immersion,” she spent an average of two weeks per visit on site and participated in the lives of the research population in numerous ways, including service as their computer tutor. With e-mail and telephone contact, she was able to continue her interactions with participants throughout the 12-year period. A long-term perspective afforded the view of the evolution, devolution or cessation of the technology use by these older adults, and this process is chronicled in detail through five individual “profiles.” Three research questions dominated the inquiry: What function do computers serve in the lives of older adults? Does computer use foster or interfere with social ties? Is social support necessary for success in the face of challenging learning tasks? In answer to the first question, it became clear that computers were valued as a symbol of competence and intelligence. Some individuals brought their computers with them when transferred to the single-room residences of assisted living or nursing care facilities. Even when use had ceased, their computers were displayed to signal that their owners were or had once been keeping up to date. In answer to the second question, computer owners socialized around computing use (with in-person family members or friends) more than, or as much as, they socialized through their computers in the digital realm of the Internet. And in answer to the third question, while the existence of social support did facilitate computer exploration, more important was the social support network generated and developed among fellow computer users.
Resumo:
AIRES, Kelson R. T.; SANTANA, André M.; MEDEIROS, Adelardo A. D. Optical flow using color information: preliminary results. In: ANNUAL ACM SYMPOSIUM ON APPLIED COMPUTING, 23., 2008, Fortaleza. Proceedings... Fortaleza: SAC, 2008.
Resumo:
The publisher regrets to inform the readers that the image that is appearing for Fig. 8 is incorrect and that the Supplementary material is missing on the published paper. The correct image for Fig. 8 and the Supplementary files are provided below: Fig. 8. (a) Timber blocks covered by invented plastic container bottom open, (b) timber blocks in the field after trial, (c) and (d) comparison between resin-coated blocks without termite damage and control blocks which were severely damaged by termites.
Resumo:
Open-cell metal foams show promise as an emerging novel material for heat exchanger applications. The high surface-area-to-volume ratio suggests increased compactness and decrease in weight of heat exchanger designs. However, the metal foam structure appears conducive to condensate retention, which would degenerate heat transfer performance. This research investigates the condensate retention behavior of aluminum open-cell metal foams through the use of static dip tests and geometrical classification via X-ray Micro-Computed Tomography. Aluminum open-cell metal foam samples of 5, 10, 20, and 40 pores per inch (PPI), all having a void fraction greater than 90%, were included in this investigation. In order to model the condensate retention behavior of metal foams, a clearer understanding of the geometry was required. After exploring the ideal geometries presented in the open literature, X-ray Micro-Computed Tomography was employed to classify the actual geometry of the metal foam samples. The images obtained were analyzed using specialized software from which geometric information including strut length and pore shapes were extracted. The results discerned a high variability in ligament length, as well as features supporting the ideal geometry known as the Weaire-Phelan unit cell. The static dip tests consisted of submerging the metal foam samples in a liquid, then allowing gravity-induced drainage until steady-state was reached and the liquid remaining in the metal foam sample was measured. Three different liquids, water, ethylene glycol, and 91% isopropyl alcohol, were employed. The behaviors of untreated samples were compared to samples subjected to a Beomite surface treatment process, and no significant differences in retention behavior were discovered. The dip test results revealed two distinct regions of condensate retention, each holding approximately half of the total liquid retained by the sample. As expected, condensate retention increased as the pores sizes decreased. A model based on surface tension was developed to predict the condensate retention in the metal foam samples and verified using a regular mesh. Applying the model to both the ideal and actual metal foam geometries showed good agreement with the dip test results in this study.
Resumo:
The forensic toxicologist faces challenges in the detection of drugs and poisons in biological samples due to transformations which occur both during life and after death. For example, changes can result from drug metabolism during life or from the use of formalin solution for post mortem embalming purposes. The former requires the identification of drug metabolites and the latter the identification of chemical reaction products in order to know which substances had been administered. The work described in this thesis was aimed at providing ways of tackling these challenges and was divided into two parts. Part 1 investigated the use of in vitro drug metabolism by human liver microsomes (HLM) to obtain information on drug metabolites and Part 2 investigated the chemical reactions of drugs and a carbamate pesticide with formalin solution and formalin-blood. The initial aim of part I was to develop an in vitro metabolism method using HLM, based on a literature review of previous studies of this type. MDMA was chosen as a model compound to develop the HLM method because its metabolism was known and standards of its metabolites were commercially available. In addition, a sensitive and selective method was developed for the identification and quantitation of hydrophilic phase I drug metabolites using LC/MS/MS with a conventional reverse-phase (C18) column. In order to obtain suitable retention factors for polar drug metabolites on this column, acetyl derivatives were evaluated for converting the metabolites to more lipophilic compounds and an optimal separation system was developed. Acetate derivatives were found to be stable in the HPLC mobile phase and to provide good chromatographic separation of the target analytes. In vitro metabolism of MDMA and, subsequently, of other drugs involved incubation of 4 µg drug substance in pH 7.4 buffer with an NADPH generating system (NGS) at 37oC for 90 min with addition of more NGS after 30 min. The reaction was stopped at 90 min by the addition of acetonitrile before extraction of the metabolites. Acetate derivatives of MDMA metabolites were identified by LC/MS/MS using multiple reaction monitoring (MRM). Three phase I metabolites (both major and minor metabolites) of MDMA were detected in HLM samples. 3,4-dihydroxy-methamphetamine and 4-hydroxy-3-methoxymethamphetamine were found to be major metabolites of MDMA whereas 3,4-methylenedioxyamphetamine was found to be a minor metabolite. Subsequently, ten MDMA positive urines were analysed to compare the metabolite patterns with those produced by HLM. An LC/MS method for MDMA and its metabolites in urine samples was developed and validated. The method demonstrated good linearity, accuracy and precision and insignificant matrix effects, with limits of quantitation of 0.025 µg/ml. Moreover, derivatives of MDMA and its metabolites were quantified in all 10 positive human urine samples. The urine metabolite pattern was found to be similar to that from HLM. The second aim of Part 1 was to use the HLM system to study the metabolism of some new psychoactive substances, whose misuse worldwide has necessitated the development of analytical methods for these drugs in biological specimens. Methylone and butylone were selected as representative cathinones and para-methoxyamphetamine (PMA) was chosen as a representative ring-substituted amphetamine, because of the involvement of these drugs in recent drug-related deaths, because of a relative lack of information on their metabolism, and because reference standards of their metabolites were not commercially available. An LC/MS/MS method for the analysis of methylone, butylone, PMA and their metabolites was developed. Three phase I metabolites of methylone and butylone were detected in HLM samples. Ketone reduction to β-OH metabolites and demethylenation to dihydroxy-metabolites were found to be major phase I metabolic pathways of butylone and methylone whereas N-demethylation to nor-methylone and nor-butylone were found to be minor pathways. Also, demethylation to para-hydroxyamphetamine was found to be a major phase I metabolic pathway of PMA whereas β-hydroxylation to β-OH-PMA was found to be a minor pathway. Formaldehyde is used for embalming, to reduce decomposition and preserve cadavers, especially in tropical countries such as Thailand. Drugs present in the body can be exposed to formaldehyde resulting in decreasing concentrations of the original compounds and production of new substances. The aim of part II of the study was to evaluate the in vitro reactions of formaldehyde with selected drug groups including amphetamines (amphetamine, methamphetamine and MDMA), benzodiazepines (alprazolam and diazepam), opiates (morphine, hydromorphone, codeine and hydrocodone) and with a carbamate insecticide (carbosulfan). The study would identify degradation products to serve as markers for the parent compounds when these were no longer detectable. Drugs standards were spiked in 10% formalin solution and 10% formalin blood. Water and whole blood without formalin were used for controls. Samples were analysed by LC/MS/MS at different times from the start, over periods of up to 30 days. Amphetamine, methamphetamine and MDMA were found to rapidly convert to methamphetamine, DMA and MDDMA respectively, in both formalin solution and formalin blood, confirming the Eschweiler-Clarke reaction between amine-containing compounds and formaldehyde. Alprazolam was found to be unstable whereas diazepam was found to be stable in both formalin solution and water. Both were found to hydrolyse in formalin solution and to give open-ring alprazolam and open-ring diazepam. Other alprazolam conversion products attached to paraformaldehyde were detected in both formalin solution and formalin blood. Morphine and codeine were found to be more stable than hydromorphone and hydrocodone in formalin solution. Conversion products of hydromorphone and hydrocodone attached to paraformaldehyde were tentatively identified in formalin solution. Moreover, hydrocodone and hydromorphone rapidly decreased within 24 h in formalin blood and could not be detected after 7 days. Carbosulfan was found to be unstable in formalin solution and was rapidly hydrolysed within 24 h, whereas in water it was stable up to 48 h. Carbofuran was the major degradation product, plus smaller amounts of other products, 3-ketocarbofuran and 3-hydrocarbofuran. By contrast, carbosulfan slowly hydrolysed in formalin-blood and was still detected after 15 days. It was concluded that HLM provide a useful tool for human drug metabolism studies when ethical considerations preclude their controlled administration to humans. The use of chemical derivatisation for hydrophilic compounds such as polar drug metabolites for analysis by LC/MS/MS with a conventional C18 column is effective and inexpensive, and suitable for routine use in the identification and quantitation of drugs and their metabolites. The detection of parent drugs and their metabolites or conversion and decomposition products is potentially very useful for the interpretation of cases in forensic toxicology, especially when the original compounds cannot be observed.
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Biobanks represent key resources for clinico-genomic research and are needed to pave the way to personalised medicine. To achieve this goal, it is crucial that scientists can securely access and share high-quality biomaterial and related data. Therefore, there is a growing interest in integrating biobanks into larger biomedical information and communication technology (ICT) infrastructures. The European project p-medicine is currently building an innovative ICT infrastructure to meet this need. This platform provides tools and services for conducting research and clinical trials in personalised medicine. In this paper, we describe one of its main components, the biobank access framework p-BioSPRE (p-medicine Biospecimen Search and Project Request Engine). This generic framework enables and simplifies access to existing biobanks, but also to offer own biomaterial collections to research communities, and to manage biobank specimens and related clinical data over the ObTiMA Trial Biomaterial Manager. p-BioSPRE takes into consideration all relevant ethical and legal standards, e.g., safeguarding donors’ personal rights and enabling biobanks to keep control over the donated material and related data. The framework thus enables secure sharing of biomaterial within open and closed research communities, while flexibly integrating related clinical and omics data. Although the development of the framework is mainly driven by user scenarios from the cancer domain, in this case, acute lymphoblastic leukaemia and Wilms tumour, it can be extended to further disease entities.