Optimization of multi-stage amplifiers in deep-submicron CMOS using a distributed/parallel genetic algorithm

IEEE International Symposium on Circuits and Systems, pp. 724 – 727, Seattle, EUA

Integration in MASCEM of the Joint Dispatch of Energy and Reserves Provided by Generation and Demand Resources

The provision of reserves in power systems is of great importance in what concerns keeping an adequate and acceptable level of security and reliability. This need for reserves and the way they are defined and dispatched gain increasing importance in the present and future context of smart grids and electricity markets due to their inherent competitive environment. This paper concerns a methodology proposed by the authors, which aims to jointly and optimally dispatch both generation and demand response resources to provide the amounts of reserve required for the system operation. Virtual Power Players are especially important for the aggregation of small size demand response and generation resources. The proposed methodology has been implemented in MASCEM, a multi agent system also developed at the authors’ research center for the simulation of electricity markets.

Upper Ontology for Multi-Agent Energy Systems’ Applications

Energy systems worldwide are complex and challenging environments. Multi-agent based simulation platforms are increasing at a high rate, as they show to be a good option to study many issues related to these systems, as well as the involved players at act in this domain. In this scope the authors research group has developed three multi-agent systems: MASCEM, which simulates the electricity markets; ALBidS that works as a decision support system for market players; and MASGriP, which simulates the internal operations of smart grids. To take better advantage of these systems, their integration is mandatory. For this reason, is proposed the development of an upper-ontology which allows an easier cooperation and adequate communication between them. Additionally, the concepts and rules defined by this ontology can be expanded and complemented by the needs of other simulation and real systems in the same areas as the mentioned systems. Each system’s particular ontology must be extended from this top-level ontology.

Elspot: Nord Pool Spot Integration in MASCEM Electricity Market Simulator

The energy sector in industrialized countries has been restructured in the last years, with the purpose of decreasing electricity prices through the increase in competition, and facilitating the integration of distributed energy resources. However, the restructuring process increased the complexity in market players' interactions and generated emerging problems and new issues to be addressed. In order to provide players with competitive advantage in the market, decision support tools that facilitate the study and understanding of these markets become extremely useful. In this context arises MASCEM (Multi-Agent Simulator of Competitive Electricity Markets), a multi-agent based simulator that models real electricity markets. To reinforce MASCEM with the capability of recreating the electricity markets reality in the fullest possible extent, it is crucial to make it able to simulate as many market models and player types as possible. This paper presents a new negotiation model implemented in MASCEM based on the negotiation model used in day-ahead market (Elspot) of Nord Pool. This is a key module to study competitive electricity markets, as it presents well defined and distinct characteristics from the already implemented markets, and it is a reference electricity market in Europe (the one with the larger amount of traded power).

Biomarkers in Solea Senegalensis Kaup, 1858 exposed to contaminated estuarine sediments: a multi-level approach

Thesis submitted to the Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia for the degree of Doctor of Philosophy in Environmental Sciences

Realistic Multi-Agent Simulation of Competitive Electricity Markets

The dynamism and ongoing changes that the electricity markets sector is constantly suffering, enhanced by the huge increase in competitiveness, create the need of using simulation platforms to support operators, regulators, and the involved players in understanding and dealing with this complex environment. This paper presents an enhanced electricity market simulator, based on multi-agent technology, which provides an advanced simulation framework for the study of real electricity markets operation, and the interactions between the involved players. MASCEM (Multi-Agent Simulator of Competitive Electricity Markets) uses real data for the creation of realistic simulation scenarios, which allow the study of the impacts and implications that electricity markets transformations bring to different countries. Also, the development of an upper-ontology to support the communication between participating agents, provides the means for the integration of this simulator with other frameworks, such as MAN-REM (Multi-Agent Negotiation and Risk Management in Electricity Markets). A case study using the enhanced simulation platform that results from the integration of several systems and different tools is presented, with a scenario based on real data, simulating the MIBEL electricity market environment, and comparing the simulation performance with the real electricity market results.

Distributed Intelligent Management of Microgrids using a Multi-Agent Simulation Platform

Multi-agent approaches have been widely used to model complex systems of distributed nature with a large amount of interactions between the involved entities. Power systems are a reference case, mainly due to the increasing use of distributed energy sources, largely based on renewable sources, which have potentiated huge changes in the power systems’ sector. Dealing with such a large scale integration of intermittent generation sources led to the emergence of several new players, as well as the development of new paradigms, such as the microgrid concept, and the evolution of demand response programs, which potentiate the active participation of consumers. This paper presents a multi-agent based simulation platform which models a microgrid environment, considering several different types of simulated players. These players interact with real physical installations, creating a realistic simulation environment with results that can be observed directly in the reality. A case study is presented considering players’ responses to a demand response event, resulting in an intelligent increase of consumption in order to face the wind generation surplus.

Sol-gel-based biosensing applied to medicinal science

Biosensors have opened new horizons in biomedical analysis, by ensuring increased assay speed and flexibility, and allowing point-of-care applications, multi-target analyses, automation and reduced costs of testing. This has been a result of many studies merging nanotechnology with biochemistry over the years, thereby enabling the creation of more suitable environments to biological receptors and their substitution by synthetic analogue materials. Sol-gel chemistry, among other materials, is deeply involved in this process. Sol-gel processing allows the immobilization of organic molecules, biomacromolecules and cells maintaining their properties and activities, permitting their integration into different transduction devices, of electrochemical or optical nature, for single or multiple analyses. Sol-gel also allows to the production of synthetic materials mimicking the activity of natural receptors, while bringing advantages, mostly in terms of cost and stability. Moreover, the biocompatibility of sol-gel materials structures of biological nature allowed the use of these materials in emerging in vivo applications. In this chapter, biosensors for biomedical applications based on sol-gel derived composites are presented, compared and described, along with current emerging applications in vivo, concerning drug delivery or biomaterials. Sol-gel materials are shown as a promising tool for current, emerging and future medical applications. - See more at: http://www.eurekaselect.com/127191/article#sthash.iPqqyhox.dpuf

Simulation Environment for Multi-Robot Cooperative 3D Target Perception

4th International Conference, SIMPAR 2014, Bergamo, Italy, October 20-23, 2014

Multi-agent simulation of competitive electricity markets: Autonomous systems cooperation for European market modeling

The electricity market restructuring, and its worldwide evolution into regional and even continental scales, along with the increasing necessity for an adequate integration of renewable energy sources, is resulting in a rising complexity in power systems operation. Several power system simulators have been developed in recent years with the purpose of helping operators, regulators, and involved players to understand and deal with this complex and constantly changing environment. The main contribution of this paper is given by the integration of several electricity market and power system models, respecting to the reality of different countries. This integration is done through the development of an upper ontology which integrates the essential concepts necessary to interpret all the available information. The continuous development of Multi-Agent System for Competitive Electricity Markets platform provides the means for the exemplification of the usefulness of this ontology. A case study using the proposed multi-agent platform is presented, considering a scenario based on real data that simulates the European Electricity Market environment, and comparing its performance using different market mechanisms. The main goal is to demonstrate the advantages that the integration of various market models and simulation platforms have for the study of the electricity markets’ evolution.

A Multiple Criteria Utility-based Approa h for the Unit Commitment with Wind Power and Pumped Storage Hydro

The integration of wind power in eletricity generation brings new challenges to unit commitment due to the random nature of wind speed. For this particular optimisation problem, wind uncertainty has been handled in practice by means of conservative stochastic scenario-based optimisation models, or through additional operating reserve settings. However, generation companies may have different attitudes towards operating costs, load curtailment, or waste of wind energy, when considering the risk caused by wind power variability. Therefore, alternative and possibly more adequate approaches should be explored. This work is divided in two main parts. Firstly we survey the main formulations presented in the literature for the integration of wind power in the unit commitment problem (UCP) and present an alternative model for the wind-thermal unit commitment. We make use of the utility theory concepts to develop a multi-criteria stochastic model. The objectives considered are the minimisation of costs, load curtailment and waste of wind energy. Those are represented by individual utility functions and aggregated in a single additive utility function. This last function is adequately linearised leading to a mixed-integer linear program (MILP) model that can be tackled by general-purpose solvers in order to find the most preferred solution. In the second part we discuss the integration of pumped-storage hydro (PSH) units in the UCP with large wind penetration. Those units can provide extra flexibility by using wind energy to pump and store water in the form of potential energy that can be generated after during peak load periods. PSH units are added to the first model, yielding a MILP model with wind-hydro-thermal coordination. Results showed that the proposed methodology is able to reflect the risk profiles of decision makers for both models. By including PSH units, the results are significantly improved.

Speed control of induction machine based on direct torque control method

Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica e de Computadores

An assessment of the integration of the mental health component into the care of women affected by intimate partner violence in Peru

RESUMO: A violência contra as mulheres (VCM) é um problema de saúde pública e uma violação dos direitos humanos. Ele tem uma alta prevalência na América Latina e no Caribe; o Estudo da Violência Contra as Mulheres da Organização Mundial de Saúde (OMS) identificou que as mulheres peruanas sofrem o maior índice de violência. O Perú é signatário da CEDAW e da Convenção de Belém do Pará, com recomendações para resolver este tipo de discriminação e descrever o papel do setor da saúde. A lei peruana define a violência como um problema de saúde mental. Objectivos: As três orientações clínicas do Ministério da Saúde para avaliar a integração da componente de saúde mental no cuidado de mulheres afetadas pela VCM foram revistas. Método: A proteção da saúde mental foi avaliada nas orientações acima mencionadas. A lei peruana relevante para perceber o reconhecimento das consequências de VCM na saúde mental e os cuidados prestados neste contexto foram revistos. Usando esses padrões nacionais e internacionais, foi realizada uma análise de conteúdo dos guias peruanos para a atenção da violência para ver como eles se integram a saúde mental. Resultados: Estas orientações são muito extensas e não definem claramente a responsabilidade dos profissionais de saúde. Não incluem um exame de saúde mental na avaliação da vítima e são vagas na descrição das atividades a serem realizadas pelo prestador dos cuidados de saúde. As orientações recomendam uma triagem universal usando um instrumento com formato antiquado e pesado. Em contrapartida, as orientações da OMS não recomendam qualquer triagem. Conclusão: As várias orientações analisadas não fornecem a informação necessária para o profissional de saúde avaliar o envolvimento da saúde mental e, desnecessariamente, tratam as mulheres sobreviventes de VCM como doentes mentais. Recomenda-se que as orientações recentes da OMS (Responding to intimate partner violence and sexual violence against women: WHO clinical and policy guidelines, 2013) para os cuidados de VCM sejam usadas como um modelo para o desenvolvimento de um único dispositivo técnico que incorpora directrizes com base científica. legislação com base no género, saúde, guias, prevenção e mujeres 6 RESUMO (PORTUGUESE) A violência contra as mulheres (VCM) é um problema de saúde pública e uma violação dos direitos humanos. Ele tem uma alta prevalência na América Latina e no Caribe; o Estudo da Violência Contra as Mulheres da Organização Mundial de Saúde (OMS) identificou que as mulheres peruanas sofrem o maior índice de violência. O Perú é signatário da CEDAW e da Convenção de Belém do Pará, com recomendações para resolver este tipo de discriminação e descrever o papel do setor da saúde. A lei peruana define a violência como um problema de saúde mental. Objectivos: As três orientações clínicas do Ministério da Saúde para avaliar a integração da componente de saúde mental no cuidado de mulheres afetadas pela VCM foram revistas. Método: A proteção da saúde mental foi avaliada nas orientações acima mencionadas. A lei peruana relevante para perceber o reconhecimento das consequências de VCM na saúde mental e os cuidados prestados neste contexto foram revistos. Usando esses padrões nacionais e internacionais, foi realizada uma análise de conteúdo dos guias peruanos para a atenção da violência para ver como eles se integram a saúde mental. Resultados: Estas orientações são muito extensas e não definem claramente a responsabilidade dos profissionais de saúde. Não incluem um exame de saúde mental na avaliação da vítima e são vagas na descrição das atividades a serem realizadas pelo prestador dos cuidados de saúde. As orientações recomendam uma triagem universal usando um instrumento com formato antiquado e pesado. Em contrapartida, as orientações da OMS não recomendam qualquer triagem. Conclusão: As várias orientações analisadas não fornecem a informação necessária para o profissional de saúde avaliar o envolvimento da saúde mental e, desnecessariamente, tratam as mulheres sobreviventes de VCM como doentes mentais. Recomenda-se que as orientações recentes da OMS (Responding to intimate partner violence and sexual violence against women: WHO clinical and policy guidelines, 2013) para os cuidados de VCM sejam usadas como um modelo para o desenvolvimento de um único dispositivo técnico que incorpora directrizes com base científica.-----------------ABSTRACT: Violence against women (VAW) is a public health problem and a human rights violation. It is highly prevalent in Latin America and the Caribbean; the Multi-country Study on Violence against Women by the World Health Organization identified rural Peruvian women as suffering the highest rates of VAW. The country is party to CEDAW and Belen Do Para Conventions, which set forth recommendations to overcome this form of discrimination and describe the role of the health sector. Peruvian law defines violence as a mental health issue. Objective: The Ministry of Health’s three technical guidelines were reviewed to assess the integration of mental health into the care of women affected by violence Method: The protection of the woman’s mental health was ascertained in the conventions mentioned above. The recognition of the mental health consequences of VAW and the inclusion of its evaluation and care were assessed in pertinent Peruvian legislation. Using these international and national parameters, the three guidelines for the attention of violence were subject to content analysis to see whether they conform to the conventions and integrate mental health care. Outcome: These guidelines are too extensive and do not clearly define the responsibility of health workers. They do not include a mental health exam in the evaluation of the victim and are vague in the description of the actions to be carried out by the health care provider. Guidelines prescribe universal screening using an outdated instrument and moreover, WHO Guidelines do not recommend screening. Conclusion: These multiple guidelines do not provide useful guidance for health care providers, particularly for the assessment of mental health sequelae, and unnecessarily stigmatize survivors of violence as mentally ill. It is recommended that the World Health Organization’s document Responding to intimate partner violence and sexual violence against women: WHO clinical and policy guidelines (2013) be used as a blueprint for only one technical instrument that incorporates evidence -based national policy and guidelines.

Analysis and implementation of a multi-ratio switched capacitor DC-DC converter for a supercapacitor power supply

An energy harvesting system requires an energy storing device to store the energy retrieved from the surrounding environment. This can either be a rechargeable battery or a supercapcitor. Due to the limited lifetime of rechargeable batteries, they need to be periodically replaced. Therefore, a supercapacitor, which has ideally a limitless number of charge/discharge cycles can be used to store the energy; however, a voltage regulator is required to obtain a constant output voltage as the supercapacitor discharges. This can be implemented by a Switched-Capacitor DC-DC converter which allows a complete integration in CMOS technology, although it requires several topologies in order to obtain a high efficiency. This thesis presents the complete analysis of four different topologies in order to determine expressions that allow to design and determine the optimum input voltage ranges for each topology. To better understand the parasitic effects, the implementation of the capacitors and the non-ideal effect of the switches, in 130 nm technology, were carefully studied. With these two analysis a multi-ratio SC DC-DC converter was designed with an output power of 2 mW, maximum efficiency of 77%, and a maximum output ripple, in the steady state, of 23 mV; for an input voltage swing of 2.3 V to 0.85 V. This proposed converter has four operation states that perform the conversion ratios of 1/2, 2/3, 1/1 and 3/2 and its clock frequency is automatically adjusted to produce a stable output voltage of 1 V. These features are implemented through two distinct controller circuits that use asynchronous time machines (ASM) to dynamically adjust the clock frequency and to select the active state of the converter. All the theoretical expressions as well as the behaviour of the whole system was verified using electrical simulations.

Visions on high-speed trains: a methodological analysis

Based on the report for the unit “Foresight Analysis Methods” of the PhD program on Technology Assessment in 2013. This unit was supervised by Prof. António Moniz. The paper had meanwhile contributions from the supervisor and Dr. Douglas Robinson.