A integração do tutorial interativo TryLogic via IMS Learning Tools Interoperability: construindo uma infraestrutura para o ensino de Lógica através de estratégias de demonstração e refutação

Logic courses represent a pedagogical challenge and the recorded number of cases of failures and of discontinuity in them is often high. Amont other difficulties, students face a cognitive overload to understand logical concepts in a relevant way. On that track, computational tools for learning are resources that help both in alleviating the cognitive overload scenarios and in allowing for the practical experimenting with theoretical concepts. The present study proposes an interactive tutorial, namely the TryLogic, aimed at teaching to solve logical conjectures either by proofs or refutations. The tool was developed from the architecture of the tool TryOcaml, through support of the communication of the web interface ProofWeb in accessing the proof assistant Coq. The goals of TryLogic are: (1) presenting a set of lessons for applying heuristic strategies in solving problems set in Propositional Logic; (2) stepwise organizing the exposition of concepts related to Natural Deduction and to Propositional Semantics in sequential steps; (3) providing interactive tasks to the students. The present study also aims at: presenting our implementation of a formal system for refutation; describing the integration of our infrastructure with the Virtual Learning Environment Moodle through the IMS Learning Tools Interoperability specification; presenting the Conjecture Generator that works for the tasks involving proving and refuting; and, finally to evaluate the learning experience of Logic students through the application of the conjecture solving task associated to the use of the TryLogic

Reconfiguração dinâmica de estratégias distribuídas em dispositivos foundation fieldbus para a otimização de processos na indústria do petróleo

The petrochemical industry has as objective obtain, from crude oil, some products with a higher commercial value and a bigger industrial utility for energy purposes. These industrial processes are complex, commonly operating with large production volume and in restricted operation conditions. The operation control in optimized and stable conditions is important to keep obtained products quality and the industrial plant safety. Currently, industrial network has been attained evidence when there is a need to make the process control in a distributed way. The Foundation Fieldbus protocol for industrial network, for its interoperability feature and its user interface organized in simple configuration blocks, has great notoriety among industrial automation network group. This present work puts together some benefits brought by industrial network technology to petrochemical industrial processes inherent complexity. For this, a dynamic reconfiguration system for intelligent strategies (artificial neural networks, for example) based on the protocol user application layer is proposed which might allow different applications use in a particular process, without operators intervention and with necessary guarantees for the proper plant functioning

Uma arquitetura de software baseada em componentes visualização de informações industriais

Due to the current need of the industry to integrate data of the beginning of production originating from of several sources and of transforming them in useful information for sockets of decisions, a search exists every time larger for systems of visualization of information that come to collaborate with that functionality. On the other hand, a common practice nowadays, due to the high competitiveness of the market, it is the development of industrial systems that possess characteristics of modularity, distribution, flexibility, scalability, adaptation, interoperability, reusability and access through web. Those characteristics provide an extra agility and a larger easiness in adapting to the frequent changes of demand of the market. Based on the arguments exposed above, this work consists of specifying a component-based architecture, with the respective development of a system based on that architecture, for the visualization of industrial data. The system was conceived to be capable to supply on-line information and, optionally, historical information of variables originating from of the beginning of production. In this work it is shown that the component-based architecture developed possesses the necessary requirements for the obtaining of a system robust, reliable and of easy maintenance, being, like this, in agreement with the industrial needs. The use of that architecture allows although components can be added, removed or updated in time of execution, through a manager of components through web, still activating more the adaptation process and updating of the system

Mecanismos de segurança para um sistema cooperativo de armazenamento de arquivos baseado em P2P

Previous works have studied the characteristics and peculiarities of P2P networks, especially security information aspects. Most works, in some way, deal with the sharing of resources and, in particular, the storage of files. This work complements previous studies and adds new definitions relating to this kind of systems. A system for safe storage of files (SAS-P2P) was specified and built, based on P2P technology, using the JXTA platform. This system uses standard X.509 and PKCS # 12 digital certificates, issued and managed by a public key infrastructure, which was also specified and developed based on P2P technology (PKIX-P2P). The information is stored in a special file with XML format which is especially prepared, facilitating handling and interoperability among applications. The intention of developing the SAS-P2P system was to offer a complementary service for Giga Natal network users, through which the participants in this network can collaboratively build a shared storage area, with important security features such as availability, confidentiality, authenticity and fault tolerance. Besides the specification, development of prototypes and testing of the SAS-P2P system, tests of the PKIX-P2P Manager module were also performed, in order to determine its fault tolerance and the effective calculation of the reputation of the certifying authorities participating in the system

Redes neurais artificiais no ambiente de redes industriais foundation fieldbus usando blocos funcionais padrões

Industrial automation networks is in focus and is gradually replacing older architectures of systems used in automation world. Among existing automation networks, most prominent standard is the Foundation Fieldbus (FF). This particular standard was chosen for the development of this work thanks to its complete application layer specification and its user interface, organized as function blocks and that allows interoperability among different vendors' devices. Nowadays, one of most seeked solutions on industrial automation are the indirect measurements, that consist in infering a value from measures of other sensors. This can be made through implementation of the so-called software sensors. One of the most used tools in this project and in sensor implementation are artificial neural networks. The absence of a standard solution to implement neural networks in FF environment makes impossible the development of a field-indirect-measurement project, besides other projects involving neural networks, unless a closed proprietary solution is used, which dos not guarantee interoperability among network devices, specially if those are from different vendors. In order to keep the interoperability, this work's goal is develop a solution that implements artificial neural networks in Foundation Fieldbus industrial network environment, based on standard function blocks. Along the work, some results of the solution's implementation are also presented

Desenvolvimento de um middleware para comunicação via web services e sua aplicação em sistemas de aquisição de dados industriais

The control of industrial processes has become increasingly complex due to variety of factory devices, quality requirement and market competition. Such complexity requires a large amount of data to be treated by the three levels of process control: field devices, control systems and management softwares. To use data effectively in each one of these levels is extremely important to industry. Many of today s industrial computer systems consist of distributed software systems written in a wide variety of programming languages and developed for specific platforms, so, even more companies apply a significant investment to maintain or even re-write their systems for different platforms. Furthermore, it is rare that a software system works in complete isolation. In industrial automation is common that, software had to interact with other systems on different machines and even written in different languages. Thus, interoperability is not just a long-term challenge, but also a current context requirement of industrial software production. This work aims to propose a middleware solution for communication over web service and presents an user case applying the solution developed to an integrated system for industrial data capture , allowing such data to be available simplified and platformindependent across the network

Um ambiente multi-middleware para desenvolvimento de aplicações distribuídas

This work presents a proposal of a multi-middleware environment to develop distributed applications, which abstracts different underlying middleware platforms. This work describes: (i) the reference architecture designed for the environment, (ii) an implementation which aims to validate the specified architecture integrating CORBA and EJB, (iii) a case study illustrating the use of the environment, (iv) a performance analysis. The proposed environment allows interoperability on middleware platforms, allowing the reuse of components of different kinds of middleware platforms in a transparency away to the developer and without major losses in performance. Also in the implementation we developed an Eclipse plugin which allows developers gain greater productivity at developing distributed applications using the proposed environment

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

Midgard: um middleware baseado em componentes e orientado a recursos para redes de sensores sem fio

On the last years, several middleware platforms for Wireless Sensor Networks (WSN) were proposed. Most of these platforms does not consider issues of how integrate components from generic middleware architectures. Many requirements need to be considered in a middleware design for WSN and the design, in this case, it is possibility to modify the source code of the middleware without changing the external behavior of the middleware. Thus, it is desired that there is a middleware generic architecture that is able to offer an optimal configuration according to the requirements of the application. The adoption of middleware based in component model consists of a promising approach because it allows a better abstraction, low coupling, modularization and management features built-in middleware. Another problem present in current middleware consists of treatment of interoperability with external networks to sensor networks, such as Web. Most current middleware lacks the functionality to access the data provided by the WSN via the World Wide Web in order to treat these data as Web resources, and they can be accessed through protocols already adopted the World Wide Web. Thus, this work presents the Midgard, a component-based middleware specifically designed for WSNs, which adopts the architectural patterns microkernel and REST. The microkernel architectural complements the component model, since microkernel can be understood as a component that encapsulates the core system and it is responsible for initializing the core services only when needed, as well as remove them when are no more needed. Already REST defines a standardized way of communication between different applications based on standards adopted by the Web and enables him to treat WSN data as web resources, allowing them to be accessed through protocol already adopted in the World Wide Web. The main goals of Midgard are: (i) to provide easy Web access to data generated by WSN, exposing such data as Web resources, following the principles of Web of Things paradigm and (ii) to provide WSN application developer with capabilities to instantiate only specific services required by the application, thus generating a customized middleware and saving node resources. The Midgard allows use the WSN as Web resources and still provide a cohesive and weakly coupled software architecture, addressing interoperability and customization. In addition, Midgard provides two services needed for most WSN applications: (i) configuration and (ii) inspection and adaptation services. New services can be implemented by others and easily incorporated into the middleware, because of its flexible and extensible architecture. According to the assessment, the Midgard provides interoperability between the WSN and external networks, such as web, as well as between different applications within a single WSN. In addition, we assessed the memory consumption, the application image size, the size of messages exchanged in the network, and response time, overhead and scalability on Midgard. During the evaluation, the Midgard proved satisfies their goals and shown to be scalable without consuming resources prohibitively

PEWS-RT, um sistema de tempo de execução para a linguagem PEWS

Web services are loosely coupled applications that use XML documents as a way of integrating distinct systems on the internet. Such documents are used by in standards such as SOAP, WSDL and UDDI which establish, respectively, integrated patterns for the representation of messages, description, and publication of services, thus facilitating the interoperability between heterogeneous systems. Often one single service does not meet the users needs, therefore new systems can be designed from the composition of two or more services. This which is the design goal behind the of the Service Oriented Architecture. Parallel to this scenario, we have the PEWS (Predicate Path-Expressions for Web Services) language, which speci es behavioural speci cations of composite web service interfaces.. The development of the PEWS language is divided into two parts: front-end and back-end. From a PEWS program, the front-end performs the lexical analysis, syntactic and semantic compositions and nally generate XML code. The function of the back-end is to execute the composition PEWS. This master's dissertation work aims to: (i) reformulate the proposed architecture for the runtime system of the language, (ii) Implement the back-end for PEWS by using .NET Framework tools to execute PEWS programs using the Windows Work ow Foundation

Modelo de interoperabilidade para utilização dos recursos dos ambientes virtuais de aprendizagem através de dispositivos móveis

The technological evolution has been making the Distance Education accessible for a greater number of citizens anytime and anywhere. The potential increase of the supply for mobile devices integrated to mobile learning environments allows that the information comes out of the physical environment, creating opportunities for students and teachers to create geographically distributed learning scenarios. However, many applications developed for these environments remain isolated from each other and do not become integrated sufficiently into the virtual learning environments (AVA). This dissertation presents an interoperability model between mobile devices and distinct AVA based on webservices. For the conception of this model, requirements engineering and software architecture techniques were used. With the goal of showing the model viability, a mobile application focused on surveys has been developed, and additionally, the main functionalities related to the interoperability were tested

Reconfiguração dinâmica de estratégias distribuídas em dispositivos foundation fieldbus para a otimização de processos na indústria do petróleo

The petrochemical industry has as objective obtain, from crude oil, some products with a higher commercial value and a bigger industrial utility for energy purposes. These industrial processes are complex, commonly operating with large production volume and in restricted operation conditions. The operation control in optimized and stable conditions is important to keep obtained products quality and the industrial plant safety. Currently, industrial network has been attained evidence when there is a need to make the process control in a distributed way. The Foundation Fieldbus protocol for industrial network, for its interoperability feature and its user interface organized in simple configuration blocks, has great notoriety among industrial automation network group. This present work puts together some benefits brought by industrial network technology to petrochemical industrial processes inherent complexity. For this, a dynamic reconfiguration system for intelligent strategies (artificial neural networks, for example) based on the protocol user application layer is proposed which might allow different applications use in a particular process, without operators intervention and with necessary guarantees for the proper plant functioning