H-N2N : uma arquitetura hierárquica escalável para ambientes de realidade mista de grande porte

In this work, we propose a solution to solve the scalability problem found in collaborative, virtual and mixed reality environments of large scale, that use the hierarchical client-server model. Basically, we use a hierarchy of servers. When the capacity of a server is reached, a new server is created as a sun of the first one, and the system load is distributed between them (father and sun). We propose efficient tools and techniques for solving problems inherent to client-server model, as the definition of clusters of users, distribution and redistribution of users through the servers, and some mixing and filtering operations, that are necessary to reduce flow between servers. The new model was tested, in simulation, emulation and in interactive applications that were implemented. The results of these experimentations show enhancements in the traditional, previous models indicating the usability of the proposed in problems of all-to-all communications. This is the case of interactive games and other applications devoted to Internet (including multi-user environments) and interactive applications of the Brazilian Digital Television System, to be developed by the research group. Keywords: large scale virtual environments, interactive digital tv, distributed

Uma arquitetura de referência para o desenvolvimento de sistemas interativos multiplataformas

It is increasingly common use of a single computer system using different devices - personal computers, telephones cellular and others - and software platforms - systems graphical user interfaces, Web and other systems. Depending on the technologies involved, different software architectures may be employed. For example, in Web systems, it utilizes architecture client-server - usually extended in three layers. In systems with graphical interfaces, it is common architecture with the style MVC. The use of architectures with different styles hinders the interoperability of systems with multiple platforms. Another aggravating is that often the user interface in each of the devices have structure, appearance and behaviour different on each device, which leads to a low usability. Finally, the user interfaces specific to each of the devices involved, with distinct features and technologies is a job that needs to be done individually and not allow scalability. This study sought to address some of these problems by presenting a reference architecture platform-independent and that allows the user interface can be built from an abstract specification described in the language in the specification of the user interface, the MML. This solution is designed to offer greater interoperability between different platforms, greater consistency between the user interfaces and greater flexibility and scalability for the incorporation of new devices

Tvoice :um sistema de manipulação de linguagens para auxiliar portadores de necessidades especiais através da web

This work presents the tVoice, software that manipulates tags languages, extracting information and, being integral part of the VoiceProxy system, it aids bearers of special needs in the access to the Web. This system is responsible for the search and treatment of the documents in the Web, extracting the textual information contained in those documents and preceding the capability of generating eventually through translation techniques, an audio script, used by the of interface subsystem of VoiceProxy, the iVoice, in the process of voice synthesis. In this stage the tVoice, besides the treatment of the tag language HTML, processes other two formats of documents, PDF and XHTML. Additionally to allow that, besides the iVoice, other interface subsystems can make use of the tVoice through remote access, we propose distribution systems techniques based in the model Client-Server providers operations of the fashion of a proxy server treatment of documents

Desenvolvimento formal de aplicações para smartcards

Smart card applications represent a growing market. Usually this kind of application manipulate and store critical information that requires some level of security, such as financial or confidential information. The quality and trustworthiness of smart card software can be improved through a rigorous development process that embraces formal techniques of software engineering. In this work we propose the BSmart method, a specialization of the B formal method dedicated to the development of smart card Java Card applications. The method describes how a Java Card application can be generated from a B refinement process of its formal abstract specification. The development is supported by a set of tools, which automates the generation of some required refinements and the translation to Java Card client (host) and server (applet) applications. With respect to verification, the method development process was formalized and verified in the B method, using the Atelier B tool [Cle12a]. We emphasize that the Java Card application is translated from the last stage of refinement, named implementation. This translation process was specified in ASF+SDF [BKV08], describing the grammar of both languages (SDF) and the code transformations through rewrite rules (ASF). This specification was an important support during the translator development and contributes to the tool documentation. We also emphasize the KitSmart library [Dut06, San12], an essential component of BSmart, containing models of all 93 classes/interfaces of Java Card API 2:2:2, of Java/Java Card data types and machines that can be useful for the specifier, but are not part of the standard Java Card library. In other to validate the method, its tool support and the KitSmart, we developed an electronic passport application following the BSmart method. We believe that the results reached in this work contribute to Java Card development, allowing the generation of complete (client and server components), and less subject to errors, Java Card applications.

RR3D: Uma solução para renderização remota de imagens médicas tridimensionais

The visualization of three-dimensional(3D)images is increasigly being sed in the area of medicine, helping physicians diagnose desease. the advances achived in scaners esed for acquisition of these 3d exames, such as computerized tumography(CT) and Magnetic Resonance imaging (MRI), enable the generation of images with higher resolutions, thus, generating files with much larger sizes. Currently, the images of computationally expensive one, and demanding the use of a righ and computer for such task. The direct remote acess of these images thruogh the internet is not efficient also, since all images have to be trasferred to the user´s equipment before the 3D visualization process ca start. with these problems in mind, this work proposes and analyses a solution for the remote redering of 3D medical images, called Remote Rendering (RR3D). In RR3D, the whole hedering process is pefomed a server or a cluster of servers, with high computational power, and only the resulting image is tranferred to the client, still allowing the client to peform operations such as rotations, zoom, etc. the solution was developed using web services written in java and an architecture that uses the scientific visualization packcage paraview, the framework paraviewWeb and the PACS server DCM4CHEE.The solution was tested with two scenarios where the rendering process was performed by a sever with graphics hadwere (GPU) and by a server without GPUs. In the scenarios without GPUs, the soluction was executed in parallel with several number of cores (processing units)dedicated to it. In order to compare our solution to order medical visualization application, a third scenario was esed in the rendering process, was done locally. In all tree scenarios, the solution was tested for different network speeds. The solution solved satisfactorily the problem with the delay in the transfer of the DICOM files, while alowing the use of low and computers as client for visualizing the exams even, tablets and smart phones

Uma proposta de solução para funcionamento offline em aplicações android

Given the growing demand for the development of mobile applications, driven by use increasingly common in smartphones and tablets grew in society the need for remote data access in full in the use of mobile application without connectivity environments where there is no provision network access at all times. Given this reality, this work proposes a framework that present main functions are the provision of a persistence mechanism, replication and data synchronization, contemplating the creation, deletion, update and display persisted or requested data, even though the mobile device without connectivity with the network. From the point of view of the architecture and programming practices, it reflected in defining strategies for the main functions of the framework are met. Through a controlled study was to validate the solution proposal, being found as the gains in reducing the number of lines code and the amount of time required to perform the development of an application without there being significant increase for the operations.

Uma proposta de solução para funcionamento offline em aplicações android

Given the growing demand for the development of mobile applications, driven by use increasingly common in smartphones and tablets grew in society the need for remote data access in full in the use of mobile application without connectivity environments where there is no provision network access at all times. Given this reality, this work proposes a framework that present main functions are the provision of a persistence mechanism, replication and data synchronization, contemplating the creation, deletion, update and display persisted or requested data, even though the mobile device without connectivity with the network. From the point of view of the architecture and programming practices, it reflected in defining strategies for the main functions of the framework are met. Through a controlled study was to validate the solution proposal, being found as the gains in reducing the number of lines code and the amount of time required to perform the development of an application without there being significant increase for the operations.