178 resultados para browser
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This paper describes an approach to a computer-based learning of educational material. We define a model for the class of subjects of our interest - teaching of investigation and prevention of computer crimes, (those including both theoretical and practical issues). From this model, specific content outlines can be derived as subclasses and then instanced into actual domains. The last step consists in generating interactive documents, which use the instanced domain. Students can explore these documents through a web browser. Thus, an interactive learning scenario is created. This approach allows reusing and adapting the contents to a variety of situations, students and teaching purposes.
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The value of knowing about data availability and system accessibility is analyzed through theoretical models of Information Economics. When a user places an inquiry for information, it is important for the user to learn whether the system is not accessible or the data is not available, rather than not have any response. In reality, various outcomes can be provided by the system: nothing will be displayed to the user (e.g., a traffic light that does not operate, a browser that keeps browsing, a telephone that does not answer); a random noise will be displayed (e.g., a traffic light that displays random signals, a browser that provides disorderly results, an automatic voice message that does not clarify the situation); a special signal indicating that the system is not operating (e.g., a blinking amber indicating that the traffic light is down, a browser responding that the site is unavailable, a voice message regretting to tell that the service is not available). This article develops a model to assess the value of the information for the user in such situations by employing the information structure model prevailing in Information Economics. Examples related to data accessibility in centralized and in distributed systems are provided for illustration.
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This paper describes a framework for building virtual collections of several digital objects and presenting them in an interactive 3D environment, rendered in a web browser. Using that environment, the website visitor can examine a given collection from a first-person perspective by walking around and inspecting each object in detail by viewing it from any angle. The rendering and visualization of the models is done solely by the web browser with the use of HTML5 and the Three.js JavaScript library, without any additional requirements.
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Image database visualisations, in particular mapping-based visualisations, provide an interesting approach to accessing image repositories as they are able to overcome some of the drawbacks associated with retrieval based approaches. However, making a mapping-based approach work efficiently on large remote image databases, has yet to be explored. In this paper, we present Web-Based Images Browser (WBIB), a novel system that efficiently employs image pyramids to reduce bandwidth requirements so that users can interactively explore large remote image databases. © 2013 Authors.
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Because some Web users will be able to design a template to visualize information from scratch, while other users need to automatically visualize information by changing some parameters, providing different levels of customization of the information is a desirable goal. Our system allows the automatic generation of visualizations given the semantics of the data, and the static or pre-specified visualization by creating an interface language. We address information visualization taking into consideration the Web, where the presentation of the retrieved information is a challenge. ^ We provide a model to narrow the gap between the user's way of expressing queries and database manipulation languages (SQL) without changing the system itself thus improving the query specification process. We develop a Web interface model that is integrated with the HTML language to create a powerful language that facilitates the construction of Web-based database reports. ^ As opposed to other papers, this model offers a new way of exploring databases focusing on providing Web connectivity to databases with minimal or no result buffering, formatting, or extra programming. We describe how to easily connect the database to the Web. In addition, we offer an enhanced way on viewing and exploring the contents of a database, allowing users to customize their views depending on the contents and the structure of the data. Current database front-ends typically attempt to display the database objects in a flat view making it difficult for users to grasp the contents and the structure of their result. Our model narrows the gap between databases and the Web. ^ The overall objective of this research is to construct a model that accesses different databases easily across the net and generates SQL, forms, and reports across all platforms without requiring the developer to code a complex application. This increases the speed of development. In addition, using only the Web browsers, the end-user can retrieve data from databases remotely to make necessary modifications and manipulations of data using the Web formatted forms and reports, independent of the platform, without having to open different applications, or learn to use anything but their Web browser. We introduce a strategic method to generate and construct SQL queries, enabling inexperienced users that are not well exposed to the SQL world to build syntactically and semantically a valid SQL query and to understand the retrieved data. The generated SQL query will be validated against the database schema to ensure harmless and efficient SQL execution. (Abstract shortened by UMI.)^
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With the exponential increasing demands and uses of GIS data visualization system, such as urban planning, environment and climate change monitoring, weather simulation, hydrographic gauge and so forth, the geospatial vector and raster data visualization research, application and technology has become prevalent. However, we observe that current web GIS techniques are merely suitable for static vector and raster data where no dynamic overlaying layers. While it is desirable to enable visual explorations of large-scale dynamic vector and raster geospatial data in a web environment, improving the performance between backend datasets and the vector and raster applications remains a challenging technical issue. This dissertation is to implement these challenging and unimplemented areas: how to provide a large-scale dynamic vector and raster data visualization service with dynamic overlaying layers accessible from various client devices through a standard web browser, and how to make the large-scale dynamic vector and raster data visualization service as rapid as the static one. To accomplish these, a large-scale dynamic vector and raster data visualization geographic information system based on parallel map tiling and a comprehensive performance improvement solution are proposed, designed and implemented. They include: the quadtree-based indexing and parallel map tiling, the Legend String, the vector data visualization with dynamic layers overlaying, the vector data time series visualization, the algorithm of vector data rendering, the algorithm of raster data re-projection, the algorithm for elimination of superfluous level of detail, the algorithm for vector data gridding and re-grouping and the cluster servers side vector and raster data caching.
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Background: Biologists often need to assess whether unfamiliar datasets warrant the time investment required for more detailed exploration. Basing such assessments on brief descriptions provided by data publishers is unwieldy for large datasets that contain insights dependent on specific scientific questions. Alternatively, using complex software systems for a preliminary analysis may be deemed as too time consuming in itself, especially for unfamiliar data types and formats. This may lead to wasted analysis time and discarding of potentially useful data. Results: We present an exploration of design opportunities that the Google Maps interface offers to biomedical data visualization. In particular, we focus on synergies between visualization techniques and Google Maps that facilitate the development of biological visualizations which have both low-overhead and sufficient expressivity to support the exploration of data at multiple scales. The methods we explore rely on displaying pre-rendered visualizations of biological data in browsers, with sparse yet powerful interactions, by using the Google Maps API. We structure our discussion around five visualizations: a gene co-regulation visualization, a heatmap viewer, a genome browser, a protein interaction network, and a planar visualization of white matter in the brain. Feedback from collaborative work with domain experts suggests that our Google Maps visualizations offer multiple, scale-dependent perspectives and can be particularly helpful for unfamiliar datasets due to their accessibility. We also find that users, particularly those less experienced with computer use, are attracted by the familiarity of the Google Maps API. Our five implementations introduce design elements that can benefit visualization developers. Conclusions: We describe a low-overhead approach that lets biologists access readily analyzed views of unfamiliar scientific datasets. We rely on pre-computed visualizations prepared by data experts, accompanied by sparse and intuitive interactions, and distributed via the familiar Google Maps framework. Our contributions are an evaluation demonstrating the validity and opportunities of this approach, a set of design guidelines benefiting those wanting to create such visualizations, and five concrete example visualizations.
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The primary purpose of this thesis was to design and develop a prototype e-commerce system where dynamic parameters are included in the decision-making process and execution of an online transaction. The system developed and implemented takes into account previous usage history, priority and associated engineering capabilities. The system was developed using three-tiered client server architecture. The interface was the Internet browser. The middle tiered web server was implemented using Active Server Pages, which form a link between the client system and other servers. A relational database management system formed the data component of the three-tiered architecture. It includes a capability for data warehousing which extracts needed information from the stored data of the customers as well as their orders. The system organizes and analyzes the data that is generated during a transaction to formulate a client's behavior model during and after a transaction. This is used for making decisions like pricing, order rescheduling during a client's forthcoming transaction. The system helps among other things to bring about predictability to a transaction execution process, which could be highly desirable in the current competitive scenario.
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Over 30% of the Antarctic continental shelf is permanently covered by floating ice shelves, providing aphotic conditions for a depauperate fauna sustained by laterally advected food. In much of the remaining Antarctic shallows (<300 m depth), seasonal sea-ice melting allows a patchy primary production supporting rich megabenthic communities dominated by glass sponges (Porifera, Hexactinellida). The catastrophic collapse of ice shelves due to rapid regional warming along the Antarctic Peninsula in recent decades has exposed over 23,000 km**2 of seafloor to local primary production. The response of the benthos to this unprecedented flux of food is, however, still unknown. In 2007, 12 years after disintegration of the Larsen A ice shelf, a first biological survey interpreted the presence of hexactinellids as remnants of a former under-ice fauna with deep-sea characteristics. Four years later, we revisited the original transect, finding 2- and 3-fold increases in glass sponge biomass and abundance, respectively, after only two favorable growth periods. Our findings, along with other long-term studies, suggest that Antarctic hexactinellids, locked in arrested growth for decades, may undergo boom-and-bust cycles, allowing them to quickly colonize new habitats. The cues triggering growth and reproduction in Antarctic glass sponges remain enigmatic.
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The marine ecosystem on the eastern shelf of the Antarctic Peninsula was surveyed 5 and 12 years after the climate-induced collapse of the Larsen A and B ice shelves. An impoverished benthic fauna was discovered, that included deep-sea species presumed to be remnants from ice-covered conditions. The current structure of various ecosystem components appears to result from extremely different response rates to the change from an oligotrophic sub-ice-shelf ecosystem to a productive shelf ecosystem. Meiobenthic communities remained impoverished only inside the embayments. On local scales, macro- and mega-epibenthic diversity was generally low, with pioneer species and typical Antarctic megabenthic shelf species interspersed. Antarctic Minke whales and seals utilised the Larsen A/B area to feed on presumably newly established krill and pelagic fish biomass. Ecosystem impacts also extended well beyond the zone of ice-shelf collapse, with areas of high benthic disturbance resulting from scour by icebergs discharged from the Larsen embayments.
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Transects of a Remotely Operated Vehicle (ROV) providing sea-bed videos and photographs were carried out during POLARSTERN expedition ANT-XVII/3 focussing on the ecology of benthic assemblages on the Antarctic shelf in the South-Eastern Weddell Sea. The ROV-system sprint 103 was equiped with two video- and one still camera, lights, flash-lights, compass, and parallel lasers providing a scale in the images, a tether-management system (TMS), a winch, and the board units. All cameras used the same main lense and could be tilted. Videos were recorded in Betacam-format and (film-)slides were made by decision of the scientific pilot. The latter were mainly made under the aspect to improve the identification of organisms depicted in the videos because the still photographs have a much higher optical resolution than the videos. In the photographs species larger than 3 mm, in the videos larger than 1 cm are recognisable and countable. Under optimum conditions the transects were strait; the speed and direction of the ROV were determined by the drift of the ship in the coastal current, since both, the ship and the ROV were used as a drifting system; the option to operate the vehicle actively was only used to avoide obstacles and to reach at best a distance of only approximately 30 cm to the sea-floor. As a consequence the width of the photographs in the foreground is approximately 50 cm. Deviations from this strategy resulted mainly from difficult ice- and weather conditions but also from high current velocity and local up-welling close to the sea-bed. The sea-bed images provide insights into the general composition of key species, higher systematic groups and ecological guilds. Within interdisciplinary approaches distributions of assemblages can be attributed to environmental conditions such as bathymetry, sediment characteristics, water masses and current regimes. The images also contain valuable information on how benthic species are associated to each other. Along the transects, small- to intermediate-scaled disturbances, e.g. by grounding icebergs were analysed and further impact to the entire benthic system by local succession of recolonisation was studied. This information can be used for models predicting the impact of climate change to benthic life in the Southern Ocean. All these approaches contribute to a better understanding of the fiunctioning of the benthic system and related components of the entire Antarctic marine ecosystem. Despite their scientific value the imaging methods meet concerns about the protection of sensitive Antarctic benthic systems since they are non-invasive and they also provide valuable material for education and outreach purposes.
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O uso das tecnologias de informação e comunicação em Portugal na área médica tem tido um grande aumento nas últimas décadas. Tal pode constatar-se a vários níveis, como sejam a implementação crescente e em larga escala de sistemas de informação em hospitais e centros de saúde, o desenvolvimento de aplicações para auxiliar a análise dos principais meios complementares de diagnóstico, a receita eletrónica e o registo de paciente eletrónico, apenas para citar alguns exemplos. A procura crescente de profissionais de saúde de várias especialidades tem tido um aumento considerável nos últimos anos. Por um lado, a população está cada vez mais envelhecida, por via do aumento da esperança média de vida. Por outro lado tem aumentado a preocupação com a saúde e o bem estar próprio dos cidadãos, levando-os a recorrer mais vezes e a mais especialidades do que no passado. O êxodo da população do interior do país para os grandes centros no litoral, complementado pelas políticas orçamentais restritivas na área da saúde, tem acentuado as diferenças de prestação de cuidados de saúde a toda a população do país, de forma equitativa e eficaz. Para tal tem ainda contribuído o emagrecimento dos orçamentos dos hospitais e a pressão para que estes cumpram as metas de produtividade definidas, com custos cada vez mais reduzidos. Um dos contributos das tecnologias de informação para mitigar o afastamento entre o paciente e os profissionais de saúde, consiste na implementação de soluções de consulta "à distância", com a utilização de vídeo e voz, através de aplicações de telemedicina. Ao nível da teleconsulta e da telemedicina têm existido alguns avanços significativos, sendo possível encontrar alguns casos de sucesso na utilização destes meios para facilitar o acesso generalizado de toda a população a cuidados médicos de saúde. Constata-se contudo que as aplicações usadas são geralmente proprietárias, carecem de instalação de software específico, muitas vezes proprietário e por vezes com custos para as entidades que disponibilizam o serviço. Por exemplo, a utilização de uma ligação por Skype para uma teleconsulta obriga a que a aplicação esteja instalada em ambos os computadores (médico e paciente). Nesta dissertação apresenta-se uma solução de telemedicina baseada na Application Programming Interface (API) Web Real-Time Comunication (WebRTC), que permite o envio de voz e imagem entre dois browsers usando os protocolos de comunicação na Web. Além do vídeo e da voz foram integrados na aplicação duas funcionalidades particularmente interessantes numa teleconsulta: envio bidirecional de ficheiros (por exemplo, ficheiro PDF com o resultado das últimas análise que o paciente realizou) e desenho num "quadro branco", permitindo ao paciente ou ao médico ilustrarem de forma livre algum aspeto associado à consulta em causa. A aplicação utiliza exclusivamente componentes de software opensource e apenas necessita que ambos os computadores tenham instalado um browser de acesso à Web que suporte a comunicação por WebRTC, como o Google Chrome ou o Firefox. Pretende-se desta forma facilitar o acesso aos serviços de telemedicina evitando a instalação e configuração de software específico, bem como reduzir os custos através de soluções opensource com licença General Public License (GPL) e isenta de custos. Foram realizados alguns testes de aceitação da solução, em ambiente hospitalar. Genericamente, pretendeu-se validar o funcionamento da API WebRTC, aferir sobre a aceitação das funcionalidades implementadas e identificar obstáculos técnicos à sua implementação na rede de um hospital ou centro de saúde. Embora tenham sido identificados alguns problemas na comunicação, resultantes maioritariamente do tipo de configurações da rede em que os computadores estavam instalados, os resultados globais obtidos são bastante promissores, dando-nos boas perspetivas quanto à sua implementação em ambiente de produção.
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Our ability to project the impact of global change on marine ecosystem is limited by our poor understanding on how to predict species sensitivity. For example, the impact of ocean acidification is highly species-specific, even in closely related taxa. The aim of this study was to test the hypothesis that the tolerance range of a given species to decreased pH corresponds to their natural range of exposure. Larvae of the green sea urchin Strongylocentrotus droebachiensis were cultured from fertilization to metamorphic competence (29 days) under a wide range of pH (from pHT = 8.0/pCO2 ~ 480 ?atm to pHT = 6.5/pCO2 ~ 20 000 ?atm) covering present (from pHT 8.7 to 7.6), projected near-future variability (from pHT 8.3 to 7.2) and beyond. Decreasing pH impacted all tested parameters (mortality, symmetry, growth, morphometry and respiration). Development of normal, although showing morphological plasticity, swimming larvae was possible as low as pHT >= 7.0. Within that range, decreasing pH increased mortality and asymmetry and decreased body length (BL) growth rate. Larvae raised at lowered pH and with similar BL had shorter arms and a wider body. Relative to a given BL, respiration rates and stomach volume both increased with decreasing pH suggesting changes in energy budget. At the lowest pHs (pHT <= 6.5), all the tested parameters were strongly negatively affected and no larva survived past 13 days post fertilization. In conclusion, sea urchin larvae appeared to be highly plastic when exposed to decreased pH until a physiological tipping point at pHT = 7.0. However, this plasticity was associated with direct (increased mortality) and indirect (decreased growth) consequences for fitness.
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Aplicação Web pode-se dizer que é uma aplicação que responde a pedidos do utilizador através de um Browser. As aplicações web orientados a objetos hoje em dia têm cada vez mais espaços nas empresas. A redução dos custos de operacionalidade e a gestão das informações, depende da visão e missão das empresas n desenvolvimento das aplicações web, enquanto uma aplicação desktop precisaria de outros meios para a sua manutenção e com maiores custos. A facilidade do acesso principalmente na ASA em que os nossos servidores estão espalhados pelos aeroportos internacionais em Cabo Verde, sem a necessidade de ser instalada num computador sendo o acesso feito apenas através do Browser. Há uma grande vantagem na atualização que só deve ser feita no servidor em vez de máquina a maquina, também como a sua escalabilidade. A aplicação escolhida para desenvolvimento vai ajudar na gestão da frota das viaturas do corpo de Bombeiros do Aeroporto Internacional Cesária Évora, designada de GestFrota, com programação em PHP, HTML, CSS, JQuery e SQL. O trabalho permite o preenchimento diário de check-list dos equipamentos, o registo das viaturas e a gestão de extintores entre outros.
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Thesis (Ph.D.)--University of Washington, 2016-06