Uma máquina de redução de grafos extensível para a implementação de fluxos de trabalho

Graph Reduction Machines, are a traditional technique for implementing functional programming languages. They allow to run programs by transforming graphs by the successive application of reduction rules. Web service composition enables the creation of new web services from existing ones. BPEL is a workflow-based language for creating web service compositions. It is also the industrial and academic standard for this kind of languages. As it is designed to compose web services, the use of BPEL in a scenario where multiple technologies need to be used is problematic: when operations other than web services need to be performed to implement the business logic of a company, part of the work is done on an ad hoc basis. To allow heterogeneous operations to be part of the same workflow, may help to improve the implementation of business processes in a principled way. This work uses a simple variation of the BPEL language for creating compositions containing not only web service operations but also big data tasks or user-defined operations. We define an extensible graph reduction machine that allows the evaluation of BPEL programs and implement this machine as proof of concept. We present some experimental results.

A PHR system with policy-based fine-grained access control and revocation mechanism

Collaborative sharing of information is becoming much more needed technique to achieve complex goals in today's fast-paced tech-dominant world. Personal Health Record (PHR) system has become a popular research area for sharing patients informa- tion very quickly among health professionals. PHR systems store and process sensitive information, which should have proper security mechanisms to protect patients' private data. Thus, access control mechanisms of the PHR should be well-defined. Secondly, PHRs should be stored in encrypted form. Cryptographic schemes offering a more suitable solution for enforcing access policies based on user attributes are needed for this purpose. Attribute-based encryption can resolve these problems, we propose a patient-centric framework that protects PHRs against untrusted service providers and malicious users. In this framework, we have used Ciphertext Policy Attribute Based Encryption scheme as an efficient cryptographic technique, enhancing security and privacy of the system, as well as enabling access revocation. Patients can encrypt their PHRs and store them on untrusted storage servers. They also maintain full control over access to their PHR data by assigning attribute-based access control to selected data users, and revoking unauthorized users instantly. In order to evaluate our system, we implemented CP-ABE library and web services as part of our framework. We also developed an android application based on the framework that allows users to register into the system, encrypt their PHR data and upload to the server, and at the same time authorized users can download PHR data and decrypt it. Finally, we present experimental results and performance analysis. It shows that the deployment of the proposed system would be practical and can be applied into practice.

La nube como apoyo a la producción audiovisual

En esta investigación analizaremos las capacidades de la nube, centrándonos en la computación (entendiendo esta como la capacidad de procesamiento) y el almacenamiento de datos geolocalizados (redes de entrega de contenidos). Estas capacidades, unidas al modelo de negocio que implica un coste cero por aprovisionamiento y el pago por uso, además de la reducción de costes mediante sinergias y optimización de los centros de datos, suponen un escenario interesante para las PYMES dedicadas a la producción audiovisual. Utilizando los servicios en la nube, una empresa pequeña puede, en cuestión de minutos, alcanzar la potencia de procesamiento y distribución de gigantes de la producción audiovisual, sin necesidad de ocupar sus instalaciones ni pagar por adelantado el alquiler de los equipos. Describiremos los servicios de AWS (Amazon Web Services) que serían útiles a una empresa, el uso que darían de dichos servicios y su coste, y lo compararemos con el presupuesto por realizar una misma instalación físicamente en dicha empresa, teniendo que comprar e instalar los equipos.

Investigation into a best practice model for providing an integrated user experience with mobile cloud applications

Mobile Cloud Computing promises to overcome the physical limitations of mobile devices by executing demanding mobile applications on cloud infrastructure. In practice, implementing this paradigm is difficult; network disconnection often occurs, bandwidth may be limited, and a large power draw is required from the battery, resulting in a poor user experience. This thesis presents a mobile cloud middleware solution, Context Aware Mobile Cloud Services (CAMCS), which provides cloudbased services to mobile devices, in a disconnected fashion. An integrated user experience is delivered by designing for anticipated network disconnection, and low data transfer requirements. CAMCS achieves this by means of the Cloud Personal Assistant (CPA); each user of CAMCS is assigned their own CPA, which can complete user-assigned tasks, received as descriptions from the mobile device, by using existing cloud services. Service execution is personalised to the user's situation with contextual data, and task execution results are stored with the CPA until the user can connect with his/her mobile device to obtain the results. Requirements for an integrated user experience are outlined, along with the design and implementation of CAMCS. The operation of CAMCS and CPAs with cloud-based services is presented, specifically in terms of service description, discovery, and task execution. The use of contextual awareness to personalise service discovery and service consumption to the user's situation is also presented. Resource management by CAMCS is also studied, and compared with existing solutions. Additional application models that can be provided by CAMCS are also presented. Evaluation is performed with CAMCS deployed on the Amazon EC2 cloud. The resource usage of the CAMCS Client, running on Android-based mobile devices, is also evaluated. A user study with volunteers using CAMCS on their own mobile devices is also presented. Results show that CAMCS meets the requirements outlined for an integrated user experience.

A cloud-based system for measuring radiation treatment plan similarity

PURPOSE: Radiation therapy is used to treat cancer using carefully designed plans that maximize the radiation dose delivered to the target and minimize damage to healthy tissue, with the dose administered over multiple occasions. Creating treatment plans is a laborious process and presents an obstacle to more frequent replanning, which remains an unsolved problem. However, in between new plans being created, the patient's anatomy can change due to multiple factors including reduction in tumor size and loss of weight, which results in poorer patient outcomes. Cloud computing is a newer technology that is slowly being used for medical applications with promising results. The objective of this work was to design and build a system that could analyze a database of previously created treatment plans, which are stored with their associated anatomical information in studies, to find the one with the most similar anatomy to a new patient. The analyses would be performed in parallel on the cloud to decrease the computation time of finding this plan. METHODS: The system used SlicerRT, a radiation therapy toolkit for the open-source platform 3D Slicer, for its tools to perform the similarity analysis algorithm. Amazon Web Services was used for the cloud instances on which the analyses were performed, as well as for storage of the radiation therapy studies and messaging between the instances and a master local computer. A module was built in SlicerRT to provide the user with an interface to direct the system on the cloud, as well as to perform other related tasks. RESULTS: The cloud-based system out-performed previous methods of conducting the similarity analyses in terms of time, as it analyzed 100 studies in approximately 13 minutes, and produced the same similarity values as those methods. It also scaled up to larger numbers of studies to analyze in the database with a small increase in computation time of just over 2 minutes. CONCLUSION: This system successfully analyzes a large database of radiation therapy studies and finds the one that is most similar to a new patient, which represents a potential step forward in achieving feasible adaptive radiation therapy replanning.

Almetrics: measuring the influence of the media on the social impact of research

Social media is changing the way we interact, present ideas and information and judge the quality of content and contributions. In recent years there have been hundreds of platforms to freely share all kinds of information and connect across networks. These new tools generate activity statistics and interactions among users such as mentions, retweets, conversations, comments on blogs or Facebook; managers references showing popularity ratings of more references shared by other researchers or repositories that generate statistics of visits or downloads of articles. This paper analyzes that have meaning and implications altmetrics, what are its advantages and critical platforms (Almetric.com, ImpactStory, Plos altmetrics, PlumX), reports progress and benefits for authors, publishers and librarians. It concluded that the value of alternative metrics as a complementary tool citation analysis is evident, although it is suggested that you should dig deeper into this issue to unravel the meaning and the potential value of these indicators to assess their potential.

ReaderBench goes Online: A Comprehension-Centered Framework for Educational Purposes

In this paper we introduce the online version of our ReaderBench framework, which includes multi-lingual comprehension-centered web services designed to address a wide range of individual and collaborative learning scenarios, as follows. First, students can be engaged in reading a course material, then eliciting their understanding of it; the reading strategies component provides an in-depth perspective of comprehension processes. Second, students can write an essay or a summary; the automated essay grading component provides them access to more than 200 textual complexity indices covering lexical, syntax, semantics and discourse structure measurements. Third, students can start discussing in a chat or a forum; the Computer Supported Collaborative Learning (CSCL) component provides indepth conversation analysis in terms of evaluating each member’s involvement in the CSCL environments. Eventually, the sentiment analysis, as well as the semantic models and topic mining components enable a clearer perspective in terms of learner’s points of view and of underlying interests.

Comparing architectural styles for distributed expert knowledge modules in intelligent tutoring systems

Intelligent Tutoring Systems (ITSs) are computerized systems for learning-by-doing. These systems provide students with immediate and customized feedback on learning tasks. An ITS typically consists of several modules that are connected to each other. This research focuses on the distribution of the ITS module that provides expert knowledge services. For the distribution of such an expert knowledge module we need to use an architectural style because this gives a standard interface, which increases the reusability and operability of the expert knowledge module. To provide expert knowledge modules in a distributed way we need to answer the research question: ‘How can we compare and evaluate REST, Web services and Plug-in architectural styles for the distribution of the expert knowledge module in an intelligent tutoring system?’. We present an assessment method for selecting an architectural style. Using the assessment method on three architectural styles, we selected the REST architectural style as the style that best supports the distribution of expert knowledge modules. With this assessment method we also analyzed the trade-offs that come with selecting REST. We present a prototype and architectural views based on REST to demonstrate that the assessment method correctly scores REST as an appropriate architectural style for the distribution of expert knowledge modules.

Gestão de trajetos fora de estrada

Anualmente, realizam-se no país inúmeras iniciativas de Todo-Terreno Turístico (TTT) onde são automaticamente registadas as coordenadas de Global Positioning System (GPS) por aplicações de dispositivos móveis. Este tipo de informação pode ser utilizada, quer para fins de divulgação turística, quer por outro tipo de entidades que necessitem de circular nesses caminhos rurais, tipicamente no meio da montanha. Entre outras, são registadas a posição, velocidade e altitude do veículo, o que permite obter informações relevantes, tais como, se o percurso se encontra transitável ou qual a velocidade recomendada. Por exemplo, durante os combates a incêndios, os bombeiros e proteção civil poderão saber se estes percursos são utilizáveis no planeamento dos combates a incêndios com reduzida probabilidade de complicações relativa ao acesso dos veículos, melhorando assim o tempo de resposta. O presente documento discute como poderá ser concebida uma aplicação web mapping, de código aberto, que permita a partilha, utilização e valorização de dados relativos aos percursos todo-terreno dos praticantes de TTT. O presente documento descreve como a aplicação desenvolvida no âmbito da dissertação de mestrado permite selecionar e ordenar possíveis trajetos que incluem os trajetos de TTT, apresentando as caraterísticas do terreno de modo a auxiliar a tomada de decisão por membros das corporações de Bombeiros. Será igualmente apresentada a interface atual da aplicação que inclui um mapa dinâmico e um gestor de pontos de referência.

Street lighting mesh network protocol

The digital revolution of the 21st century contributed to stem the Internet of Things (IoT). Trillions of embedded devices using the Internet Protocol (IP), also called smart objects, will be an integral part of the Internet. In order to support such an extremely large address space, a new Internet Protocol, called Internet Protocol Version 6 (IPv6) is being adopted. The IPv6 over Low Power Wireless Personal Area Networks (6LoWPAN) has accelerated the integration of WSNs into the Internet. At the same time, the Constrained Application Protocol (CoAP) has made it possible to provide resource constrained devices with RESTful Web services functionalities. This work builds upon previous experience in street lighting networks, for which a proprietary protocol, devised by the Lighting Living Lab, was implemented and used for several years. The proprietary protocol runs on a broad range of lighting control boards. In order to support heterogeneous applications with more demanding communication requirements and to improve the application development process, it was decided to port the Contiki OS to the four channel LED driver (4LD) board from Globaltronic. This thesis describes the work done to adapt the Contiki OS to support the Microchip TM PIC24FJ128GA308 microprocessor and presents an IP based solution to integrate sensors and actuators in smart lighting applications. Besides detailing the system’s architecture and implementation, this thesis presents multiple results showing that the performance of CoAP based resource retrievals in constrained nodes is adequate for supporting networking services in street lighting networks.

Implementação de um modelo baseado em XML para suporte da dinâmica processual de negócio

Este artigo descreve um modelo para implementação de plataformas dinâmicas de negócio, exclusivamente baseadas em tecnologias XML. Apresenta um caso real que implementa as suas diversas camadas, apresentação, lógica e dados, em XML. A comunicação entre camadas é assegurada por serviços Web (WS), tornando esta arquitectura orientada aos serviços (SOA). O modelo proposto sustenta toda a programação do processo de negócio numa linguagem de alto nível, o WS-BPEL, proporcionando, desse modo, condições de adaptação ao dinamismo exigido pelo negócio da organização e à heterogeneidade dos sistemas. O caso real é de uma secretaria electrónica que surge no contexto dos portais Web universitários. O sistema desenvolvido visa oferecer um conjunto de serviços para acesso a informação e para o despoletar de acções computacionais e/ou humanas.

Secretaria on-line from ISCAP

Like many other higher educat ion schools, ISCAP`s population has grown at a rate of almost 100% in the end of the twentieth century. Its administrative structures were reinforced, but it was not in the same proportion. Face to face with the inability to resolve the problem, the administration decided to implement a computer based system, available in the Internet. In a first stage, in 1997, the system was implemented as a services support. The next stage, in 1999, proposes to increase student services quality. A project that aims to bring student services available on the Internet begins to be developed.

Technology strategies in the process of student retention and efficiency of academic management

This article discusses the application of Information and Communication Technologies and strategies for best practices in order to capture and maintain faculty students' attention. It is based on a case study of ten years, using a complete information system. This system, in addition to be considered an ERP, to support the activities of academic management, also has a strong component of SRM that provides support to academic and administrative activities. It describes the extent to which the presented system facilitates the interaction and communication between members of the academic community, using the Internet, with services available on the Web complementing them with email, SMS and CTI. Through a perception, backed by empirical analysis and results of investigations, it demonstrates how this type of practice may raise the level of satisfaction of the community. In particular, it is possible to combat failure at school, avoid that students leave their course before its completion and also that they recommend them to potential students. In addition, such a strategy also allows strong economies in the management of the institution, increasing its value. As future work, we present the new phase of the project towards implementation of Business Intelligence to optimize the management process, making it proactive. The technological vision that guides new developments to a construction based on Web services and procedural languages is also presented.

Semantic features for context organization

In recent years the technological world has grown by incorporating billions of small sensing devices, collecting and sharing real-world information. As the number of such devices grows, it becomes increasingly difficult to manage all these new information sources. There is no uniform way to share, process and understand context information. In previous publications we discussed efficient ways to organize context information that is independent of structure and representation. However, our previous solution suffers from semantic sensitivity. In this paper we review semantic methods that can be used to minimize this issue, and propose an unsupervised semantic similarity solution that combines distributional profiles with public web services. Our solution was evaluated against Miller-Charles dataset, achieving a correlation of 0.6.

Interoperabilidade, processamento e análise visual de dados geográficos

Esta dissertação apresenta uma arquitectura interoperável que permite lidar com a obtenção, manipulação, processamento e análise de informação geográfica. A aplicação 30, implementada como parte da arquitectura, para além de permitir a visualização e manipulação de dados dentro de um ambiente 30, oferece métodos que permitem descobrir, aceder e usar geo-processos, disponíveis através de serviços Web. A interacção com o utilizador é também feita através uma abordagem que quebra a típica complexidade que a maioria dos Sistemas de Informação Geográfica apresenta. O recurso à programação visual reduz a complexidade do sistema, e permite aos operadores tirar proveito da localização e de uma abstracção de um processo complexo, onde as unidades de processamento são representadas no terreno através de componentes 30 que podem ser directamente manipuladas e ligadas de modo a criar encandeamentos complexos de processos. Estes processos podem também ser criados visualmente e disponibilizados online. ABSTRACT; This thesis presents an interoperable architecture mainly designed for manipulation, processing and geographical information analysis. The three-dimensional interface, implemented as part of the architecture, besides allowing the visualization and manipulation of spatial data within a 30 environment, offers methods for discovering, accessing and using geo-processes, available through Web Services. Furthermore, the user interaction is done through an approach that breaks the typical complexity of most Geographic information Systems. This simplicity is in general archived through a visual programming approach that allows operators to take advantage of location, and use processes through abstract representations. Thus, processing units are represented on the terrain through 30 components, which can be directly manipulated and linked to create complex process chains. New processes can also be visually created and deployed online.