Ferramenta de apoio ao projeto, configuração e gestão de instalações domóticas

Esta dissertação apresenta o trabalho realizado no âmbito da unidade curricular de Tese / Dissertação (TEDI) do Mestrado em Engenharia Eletrotécnica e de Computadores – Especialização em Automação e Sistemas em parceria com a empresa Live Simply, uma empresa de domótica que decidiu apostar na inovação e no desenvolvimento de serviços e produtos de valor acrescentado para consolidar a sua posição no mercado. Neste contexto, foram identificadas como mais-valias para a Live Simply a conceção, por um lado, de uma ferramenta de apoio técnico de integração e simplificação das fases de projeto, configuração e gestão de instalações domóticas e, por outro lado, de uma interface com a instalação para o cliente consultar e alterar, em tempo real, o estado dos atuadores. Depois de analisadas as tecnologias disponíveis, selecionaram-se as soluções a adotar (linguagens de programação, servidores de base de dados e ambientes de desenvolvimento), definiu-se a arquitetura do sistema, detalhando-se os módulos de projeto, configuração e gestão de instalações, a estrutura da base de dados assim como o hardware de controlo da instalação. De seguida, procedeu-se ao desenvolvimento dos módulos de software e à configuração e programação do módulo de hardware. Por último, procedeu-se a um conjunto exaustivo de testes aos diferentes módulos que demonstraram o correto funcionamento da ferramenta e a adequação das tecnologias empregues. A ferramenta de apoio técnico realizada integra as fases do projeto, configuração e gestão de instalações domóticas, permitindo melhorar o desempenho dos técnicos e a resposta aos clientes. A interface oferecida ao dono da instalação é uma interface Web de aspeto amigável e fácil utilização que permite consultar e modificar em tempo real o estado da instalação.

Sistema de Visão Stereo Ativo aplicado aos robôs do ISePorto

A presente dissertação endereça o desenvolvimento de um sistema de visão stereo ativo para os robôs de futebol robótico da equipa ISePorto do ISEP, de modo a que estes tirem o máximo partido das câmaras rotativas neles existentes. Este trabalho surge da necessidade de melhorar a capacidade de perceção do ambiente por parte dos robôs, principalmente da perceção da bola quando não está no plano do campo e dos robôs adversários. Esta necessidade surge devido ao aumento da dinâmica que se tem vindo a veri car ultimamente nas competições. Para tal, foram estudados algumas trabalhos relacionados no que diz respeito a sistemas de visão stereo com baselines variáveis e eixos de rotação em ambas as câmaras, bem como fundamentos de visão stereo. Foi proposta uma arquitetura para o sistema de visão ativo de modo a ser aplicado em qualquer robô da equipa MSL (Middle Size League). Para tornar possível a implementação desta arquitetura foi desenvolvido um procedimento para a calibração e determinação em tempo real dos parâmetros extrínsecos do par stereo em função da posição angular dos eixos rotativos do robô. O sistema de visão foi também dotado de capacidade de sincronismo e foram implementadas funcionalidades ao nível de software que possibilitam a deteção de objetos na imagem, a correspondência de objetos presentes nas imagens de ambas as câmaras e consequentemente a determinação das posições tridimensionais desses objetos relativamente ao robô. O sistema desenvolvido foi testado e validado em cenário MSL ao nível de perceção da bola, robôs adversários e linhas do campo. Os resultados obtidos apresentam uma melhoria signi cativa, face à implementação atual dos robôs, na perceção tridimensional da bola quando não está no plano do campo, e dos robôs adversários.

New insights on integer-programming models for the kidney exchange problem

In recent years several countries have set up policies that allow exchange of kidneys between two or more incompatible patient–donor pairs. These policies lead to what is commonly known as kidney exchange programs. The underlying optimization problems can be formulated as integer programming models. Previously proposed models for kidney exchange programs have exponential numbers of constraints or variables, which makes them fairly difficult to solve when the problem size is large. In this work we propose two compact formulations for the problem, explain how these formulations can be adapted to address some problem variants, and provide results on the dominance of some models over others. Finally we present a systematic comparison between our models and two previously proposed ones via thorough computational analysis. Results show that compact formulations have advantages over non-compact ones when the problem size is large.

CrimsonHex: a learning objects repository for programming exercises

A repository of learning objects is a system that stores electronic resources in a technology-mediated learning process. The need for this kind of repository is growing as more educators become eager to use digital educa- tional contents and more of it becomes available. The sharing and use of these resources relies on the use of content and communication standards as a means to describe and exchange educational resources, commonly known as learning objects. This paper presents the design and implementation of a service-oriented reposi- tory of learning objects called crimsonHex. This repository supports new definitions of learning objects for specialized domains and we illustrate this feature with the definition of programming exercises as learning objects and its validation by the repository. The repository is also fully compliant with existing commu- nication standards and we propose extensions by adding new functions, formalizing message interchange and providing a REST interface. To validate the interoperability features of the repository, we developed a repository plug-in for Moodle that is expected to be included in the next release of this popular learning management system.

Mixed integer non linear programming and artificial neural network based approach to ancillary services dispatch in competitive electricity markets

Ancillary services represent a good business opportunity that must be considered by market players. This paper presents a new methodology for ancillary services market dispatch. The method considers the bids submitted to the market and includes a market clearing mechanism based on deterministic optimization. An Artificial Neural Network is used for day-ahead prediction of Regulation Down, regulation-up, Spin Reserve and Non-Spin Reserve requirements. Two test cases based on California Independent System Operator data concerning dispatch of Regulation Down, Regulation Up, Spin Reserve and Non-Spin Reserve services are included in this paper to illustrate the application of the proposed method: (1) dispatch considering simple bids; (2) dispatch considering complex bids.

Distributed computer-controlled systems: the DEAR-COTS approach

This paper proposes a new architecture targeting real-time and reliable Distributed Computer-Controlled Systems (DCCS). This architecture provides a structured approach for the integration of soft and/or hard real-time applications with Commercial O -The-Shelf (COTS) components. The Timely Computing Base model is used as the reference model to deal with the heterogeneity of system components with respect to guaranteeing the timeliness of applications. The reliability and availability requirements of hard real-time applications are guaranteed by a software-based fault-tolerance approach.

Replication management in reliable real-time systems

Building reliable real-time applications on top of commercial off-the-shelf (COTS) components is not a straightforward task. Thus, it is essential to provide a simple and transparent programming model, in order to abstract programmers from the low-level implementation details of distribution and replication. However, the recent trend for incorporating pre-emptive multitasking applications in reliable real-time systems inherently increases its complexity. It is therefore important to provide a transparent programming model, enabling pre-emptive multitasking applications to be implemented without resorting to simultaneously dealing with both system requirements and distribution and replication issues. The distributed embedded architecture using COTS components (DEAR-COTS) architecture has been previously proposed as an architecture to support real-time and reliable distributed computer-controlled systems (DCCS) using COTS components. Within the DEAR-COTS architecture, the hard real-time subsystem provides a framework for the development of reliable real-time applications, which are the core of DCCS applications. This paper presents the proposed framework, and demonstrates how it can be used to support the transparent replication of software components.

Supporting real-time distributed computer-controlled systems with multi-hop P-NET networks

Fieldbus communication networks aim to interconnect sensors, actuators and controllers within process control applications. Therefore, they constitute the foundation upon which real-time distributed computer-controlled systems can be implemented. P-NET is a fieldbus communication standard, which uses a virtual token-passing medium-access-control mechanism. In this paper pre-run-time schedulability conditions for supporting real-time traffic with P-NET networks are established. Essentially, formulae to evaluate the upper bound of the end-to-end communication delay in P-NET messages are provided. Using this upper bound, a feasibility test is then provided to check the timing requirements for accessing remote process variables. This paper also shows how P-NET network segmentation can significantly reduce the end-to-end communication delays for messages with stringent timing requirements.

An architecture for reliable distributed computer-controlled systems

In Distributed Computer-Controlled Systems (DCCS), both real-time and reliability requirements are of major concern. Architectures for DCCS must be designed considering the integration of processing nodes and the underlying communication infrastructure. Such integration must be provided by appropriate software support services. In this paper, an architecture for DCCS is presented, its structure is outlined, and the services provided by the support software are presented. These are considered in order to guarantee the real-time and reliability requirements placed by current and future systems.

A communication support for real-time distributed computer controlled systems

In this paper, we analyse the ability of P-NET [1] fieldbus to cope with the timing requirements of a Distributed Computer Control System (DCCS), where messages associated to discrete events should be made available within a maximum bound time. The main objective of this work is to analyse how the network access and queueing delays, imposed by P-NET’s virtual token Medium Access Control (MAC) mechanism, affect the realtime behaviour of the supported DCCS.

Nano-CF: a Coordination Framework for macro-programming in wireless sensor networks

Wireless Sensor Networks (WSN) are being used for a number of applications involving infrastructure monitoring, building energy monitoring and industrial sensing. The difficulty of programming individual sensor nodes and the associated overhead have encouraged researchers to design macro-programming systems which can help program the network as a whole or as a combination of subnets. Most of the current macro-programming schemes do not support multiple users seamlessly deploying diverse applications on the same shared sensor network. As WSNs are becoming more common, it is important to provide such support, since it enables higher-level optimizations such as code reuse, energy savings, and traffic reduction. In this paper, we propose a macro-programming framework called Nano-CF, which, in addition to supporting in-network programming, allows multiple applications written by different programmers to be executed simultaneously on a sensor networking infrastructure. This framework enables the use of a common sensing infrastructure for a number of applications without the users having to worrying about the applications already deployed on the network. The framework also supports timing constraints and resource reservations using the Nano-RK operating system. Nano- CF is efficient at improving WSN performance by (a) combining multiple user programs, (b) aggregating packets for data delivery, and (c) satisfying timing and energy specifications using Rate- Harmonized Scheduling. Using representative applications, we demonstrate that Nano-CF achieves 90% reduction in Source Lines-of-Code (SLoC) and 50% energy savings from aggregated data delivery.

A framework for programming sensor networks with scheduling and resource-sharing optimizations

Several projects in the recent past have aimed at promoting Wireless Sensor Networks as an infrastructure technology, where several independent users can submit applications that execute concurrently across the network. Concurrent multiple applications cause significant energy-usage overhead on sensor nodes, that cannot be eliminated by traditional schemes optimized for single-application scenarios. In this paper, we outline two main optimization techniques for reducing power consumption across applications. First, we describe a compiler based approach that identifies redundant sensing requests across applications and eliminates those. Second, we cluster the radio transmissions together by concatenating packets from independent applications based on Rate-Harmonized Scheduling.

sMapReduce: a programming pattern for wireless sensor networks

Wireless Sensor Networks (WSNs) are increasingly used in various application domains like home-automation, agriculture, industries and infrastructure monitoring. As applications tend to leverage larger geographical deployments of sensor networks, the availability of an intuitive and user friendly programming abstraction becomes a crucial factor in enabling faster and more efficient development, and reprogramming of applications. We propose a programming pattern named sMapReduce, inspired by the Google MapReduce framework, for mapping application behaviors on to a sensor network and enabling complex data aggregation. The proposed pattern requires a user to create a network-level application in two functions: sMap and Reduce, in order to abstract away from the low-level details without sacrificing the control to develop complex logic. Such a two-fold division of programming logic is a natural-fit to typical sensor networking operation which makes sensing and topological modalities accessible to the user.

Using a prioritized MAC protocol to execute the database operation join in networked embedded computer systems

Database query languages on relations (for example SQL) make it possible to join two relations. This operation is very common in desktop/server database systems but unfortunately query processing systems in networked embedded computer systems currently do not support this operation; specifically, the query processing systems TAG, TinyDB, Cougar do not support this. We show how a prioritized medium access control (MAC) protocol can be used to efficiently execute the database operation join for networked embedded computer systems where all computer nodes are in a single broadcast domain.

Object transportation by multiple mobile robots controlled by attractor dynamics: theory and implementation

Dynamical systems theory is used as a theoretical language and tool to design a distributed control architecture for teams of mobile robots, that must transport a large object and simultaneously avoid collisions with (either static or dynamic) obstacles. Here we demonstrate in simulations and implementations in real robots that it is possible to simplify the architectures presented in previous work and to extend the approach to teams of n robots. The robots have no prior knowledge of the environment. The motion of each robot is controlled by a time series of asymptotical stable states. The attractor dynamics permits the integration of information from various sources in a graded manner. As a result, the robots show a strikingly smooth an stable team behaviour.