15 resultados para External electronic poling
em Instituto Politécnico do Porto, Portugal
Resumo:
This paper presents a Multi-Agent Market simulator designed for developing new agent market strategies based on a complete understanding of buyer and seller behaviors, preference models and pricing algorithms, considering user risk preferences and game theory for scenario analysis. This tool studies negotiations based on different market mechanisms and, time and behavior dependent strategies. The results of the negotiations between agents are analyzed by data mining algorithms in order to extract rules that give agents feedback to improve their strategies. The system also includes agents that are capable of improving their performance with their own experience, by adapting to the market conditions, and capable of considering other agent reactions.
Resumo:
This paper presents a Multi-Agent Market simulator designed for analyzing agent market strategies based on a complete understanding of buyer and seller behaviors, preference models and pricing algorithms, considering user risk preferences and game theory for scenario analysis. The system includes agents that are capable of improving their performance with their own experience, by adapting to the market conditions, and capable of considering other agents reactions.
Resumo:
This paper presents an agent-based simulator designed for analyzing agent market strategies based on a complete understanding of buyer and seller behaviours, preference models and pricing algorithms, considering user risk preferences. The system includes agents that are capable of improving their performance with their own experience, by adapting to the market conditions. In the simulated market agents interact in several different ways and may joint together to form coalitions. In this paper we address multi-agent coalitions to analyse Distributed Generation in Electricity Markets
Resumo:
With the increasing importance of large commerce across the Internet it is becoming increasingly evident that in a few years the Iternet will host a large number of interacting software agents. a vast number of them will be economically motivated, and will negociate a variety of goods and services. It is therefore important to consider the economic incentives and behaviours of economic software agents, and to use all available means to anticipate their collective interactions. This papers addresses this concern by presenting a multi-agent market simulator designed for analysing agent market strategies based on a complete understanding of buyer and seller behaviours, preference models and pricing algorithms, consideting risk preferences. The system includes agents that are capable of increasing their performance with their own experience, by adapting to the market conditions. The results of the negotiations between agents are analysed by data minig algorithms in order to extract rules that give agents feedback to imprive their strategies.
Resumo:
Neste trabalho é desenvolvida uma bancada didáctica que permite simular o funcionamento de um sistema de microgeração. A bancada inclui uma máquina síncrona responsável pela geração de energia eléctrica acoplada a uma máquina de indução que simula a máquina primária. A máquina de indução é controlada por um sistema electrónico de controlo de potência (variador de velocidade) que permite manter constante a velocidade de rotação e consequentemente a frequência da tensão gerada pela máquina síncrona. Por sua vez, a excitação da máquina síncrona é controla por uma fonte de tensão externa. A parametrização e controlo do variador de velocidade, assim como o controlo da fonte de tensão externa, são feitos a partir dum software que corre num PC, que também monitoriza a tensão gerada pela máquina síncrona. Este software é ainda responsável pela interface com o utilizador. O software desenvolvido permite manter as características da tensão gerada pela máquina síncrona independentemente da carga imposta.
Oxidative Leaching of metals from electronic waste with solutions based on quaternary ammonium salts
Resumo:
The treatment of electric and electronic waste (WEEE) is a problem which receives ever more attention. An inadequate treatment results in harmful products ending up in the environment. This project intends to investigate the possibilities of an alternative route for recycling of metals from printed circuit boards (PCBs) obtained from rejected computers. The process is based on aqueous solutions composed of an etchant, either 0.2 M CuCl2.2H2O or 0.2 M FeCl3.6H2O, and a quaternary ammonium salt (quat) such as choline chloride or chlormequat. These solutions are reminiscent of deep eutectic solvents (DES) based on quats. DES are quite similar to ionic liquids (ILs) and are used as well as alternative solvents with a great diversity of physical properties, making them attractive for replacement of hazardous, volatile solvents (e.g. VOCs). A remarkable difference between genuine DES and ILs with the solutions used in this project is the addition of rather large quantities of water. It is shown the presence of water has a lot of advantages on the leaching of metals, while the properties typical for DES still remain. The oxidizing capacities of Cu(II) stem from the existence of a stable Cu(I) component in quat based DES and thus the leaching stems from the activity of the Cu(II)/Cu(I) redox couple. The advantage of Fe(III) in combination with DES is the fact that the Fe(III)/Fe(II) redox couple becomes reversible, which is not true in pure water. This opens perspectives for regeneration of the etching solution. In this project the leaching of copper was studied as a function of gradual increasing water content from 0 - 100w% with the same concentration of copper chloride or iron(III) chloride at room temperature and 80ºC. The solutions were also tested on real PCBs. At room temperature a maximum leaching effect for copper was obtained with 30w% choline chloride with 0.2 M CuCl2.2H2O. The leaching effect is still stronger at 80°C, b ut of course these solutions are more energy consuming. For aluminium, tin, zinc and lead, the leaching was faster at 80ºC. Iron and nickel dissolved easily at room temperature. The solutions were not able to dissolve gold, silver, rhodium and platinum.
Resumo:
Activity rhythms in animal groups arise both from external changes in the environment, as well as from internal group dynamics. These cycles are reminiscent of physical and chemical systems with quasiperiodic and even chaotic behavior resulting from “autocatalytic” mechanisms. We use nonlinear differential equations to model how the coupling between the self-excitatory interactions of individuals and external forcing can produce four different types of activity rhythms: quasiperiodic, chaotic, phase locked, and displaying over or under shooting. At the transition between quasiperiodic and chaotic regimes, activity cycles are asymmetrical, with rapid activity increases and slower decreases and a phase shift between external forcing and activity. We find similar activity patterns in ant colonies in response to varying temperature during the day. Thus foraging ants operate in a region of quasiperiodicity close to a cascade of transitions leading to chaos. The model suggests that a wide range of temporal structures and irregularities seen in the activity of animal and human groups might be accounted for by the coupling between collectively generated internal clocks and external forcings.
Resumo:
Introdução: Os exercícios de fortalecimento dos músculos do pavimento pélvico (EFMPP) são considerados a primeira intervenção no tratamento da incontinência urinária de esforço (IUE), porém os EFMPP são distintos, não existindo evidência sobre os parâmetros de treino. Objetivo: Identificar o protocolo e/ ou os parâmetros de treino dos músculos do pavimento pélvico (MPP) mais eficaz no tratamento da IUE feminina. Método: A pesquisa bibliográfica foi realizada entre janeiro de 1992 a março de 2014 nas bases de dados PubMed, Cochrane Library, PEDro, web of Science e LILACS. Os artigos incluídos eram de língua inglesa, estudos experimentais, no qual comparavam EFMPP com o tratamento placebo, usual ou sem tratamento, com idade compreendida entre os 18 e os 65 anos e diagnóstico de IUE. Os critérios de exclusão abrangeram o diagnóstico de IUE desencadeada por fatores externos ao trato urinário inferior, grávidas, puérperas, prolapso ≥ 2 e outros tipos de IU. A avaliação da qualidade metodológica for realizada através da escala PEDro. Resultados: Sete artigos de elevada qualidade metodológica foram incluídos na presente revisão. A amostra foi constituída por 331 mulheres, com idade média de 44,4 anos, duração média das perdas urinárias de 64 meses e a gravidade da IUE variou entre ligeira a severa. Os programas de EFMPP eram distintos em relação aos parâmetros de treino dos MPP, sendo que alguns estudos incluíram o treino abdominal, supervisão e técnicas adjuvantes. A taxa de curada da quantidade de perda urinária variou entre 28,6 a 80%, enquanto a força dos MPP variou de 15,6% a 161,7%. Conclusão: Na presente revisão sistemática, os EFMPP combinados com palpação digital, biofeedback e cones vaginais parecem ser mais eficazes na redução da quantidade de perda urinária, comparado com os EFMPP isolados ou sem tratamento. Esta revisão permitiu igualmente identificar as 12 semanas de duração da intervenção, 10 repetições por série e diferentes posições, sendo os parâmetros de treino mais consistentes na redução dos sintomas.
Resumo:
Introdução: Os exercícios de fortalecimento dos músculos do pavimento pélvico (EFMPP) são considerados a primeira intervenção no tratamento da incontinência urinária de esforço (IUE), porém os EFMPP são distintos, não existindo evidência sobre os parâmetros de treino. Objetivo: Identificar o protocolo e/ ou os parâmetros de treino dos músculos do pavimento pélvico (MPP) mais eficaz no tratamento da IUE feminina. Método: A pesquisa bibliográfica foi realizada entre janeiro de 1992 a março de 2014 nas bases de dados PubMed, Cochrane Library, PEDro, web of Science e LILACS. Os artigos incluídos eram de língua inglesa, estudos experimentais, no qual comparavam EFMPP com o tratamento placebo, usual ou sem tratamento, com idade compreendida entre os 18 e os 65 anos e diagnóstico de IUE. Os critérios de exclusão abrangeram o diagnóstico de IUE desencadeada por fatores externos ao trato urinário inferior, grávidas, puérperas, prolapso ≥ 2 e outros tipos de IU. A avaliação da qualidade metodológica for realizada através da escala PEDro. Resultados: Sete artigos de elevada qualidade metodológica foram incluídos na presente revisão. A amostra foi constituída por 331 mulheres, com idade média de 44,4 anos, duração média das perdas urinárias de 64 meses e a gravidade da IUE variou entre ligeira a severa. Os programas de EFMPP eram distintos em relação aos parâmetros de treino dos MPP, sendo que alguns estudos incluíram o treino abdominal, supervisão e técnicas adjuvantes. A taxa de curada da quantidade de perda urinária variou entre 28,6 a 80%, enquanto a força dos MPP variou de 15,6% a 161,7%. Conclusão: Na presente revisão sistemática, os EFMPP combinados com palpação digital, biofeedback e cones vaginais parecem ser mais eficazes na redução da quantidade de perda urinária, comparado com os EFMPP isolados ou sem tratamento. Esta revisão permitiu igualmente identificar as 12 semanas de duração da intervenção, 10 repetições por série e diferentes posições, sendo os parâmetros de treino mais consistentes na redução dos sintomas.
Resumo:
The operation of distribution networks has been facing changes with the implementation of smart grids and microgrids, and the increasing use of distributed generation. The specific case of distribution networks that accommodate residential buildings, small commerce, and distributed generation as the case of storage and PV generation lead to the concept of microgrids, in the cases that the network is able to operate in islanding mode. The microgrid operator in this context is able to manage the consumption and generation resources, also including demand response programs, obtaining profits from selling electricity to the main network. The present paper proposes a methodology for the energy resource scheduling considering power flow issues and the energy buying and selling from/to the main network in each bus of the microgrid. The case study uses a real distribution network with 25 bus, residential and commercial consumers, PV generation, and storage.
Resumo:
The current study aimed to compare the shoulder kinematics (3D scapular orientation, scapular angular displacement and scapulohumeral rhythm) of asymptomatic participants under unloaded and loaded conditions during unilateral shoulder elevation in the scapular plane. We used a repeated-measures design with a convenience sample. Eleven male participants with an age range of 21–28 years with no recent history of shoulder injury participated in the study. The participants performed isometric shoulder elevation from a neutral position to approximately 150 degrees of elevation in the scapular plane in intervals of approximately 30 degrees during unloaded and loaded conditions. Shoulder kinematic data were obtained with videogrammetry. During shoulder elevation, the scapula rotated upwardly and externally, and tilted posteriorly. The addition of an external load did not affect 3D scapular orientation, scapular angular displacement, or scapulohumeral rhythm throughout shoulder elevation (P > .05). In clinical practice, clinicians should expect to observe upward and external rotation and posterior tilt of the scapula during their assessments of shoulder elevation. Such behavior was not influenced by an external load normalized to 5% of body weight when performed in an asymptomatic population.
Resumo:
Workshop on ns-3 (WNS '15). 13, May, 2015. Castelldefels, Spain.
Resumo:
To improve surgical safety, and to reduce the mortality and surgical complications incidence, the World Health Organization (WHO) developed the Surgical Safety Checklist (SSC). The SSC is a support of information that aids health professionals to reduce the number of complications, induction of anaesthesia, period before skin incision and period before leaving the operating room (OR). The SSC was tested in several countries of the world and their results shown that after introduction of the SSC the incidence of patient complication lowered from 11.0% to 7.0% (P<0.001), the rate of death declined from 1.5% to 0.8% (P = 0.003) and the nurses recognized that patients identity was more often con rmed (81.6% to 94.2%, P<0.01) in many institutions. Recently the SSC was also implemented in Portuguese hospitals, which led us to its study in the real clinical environment. An observational study was performed: several health professionals were observed and interviewed, to understand the functioning of the SSC in an OR, during the clinical routine. The objective of this study was to understand the current use of the SSC, and how it may be improved in terms of usability, taking advantage of the technological advancements such as mobile applications. During two days were observed 14 surgeries, only 2 surgeries met the requirements for the three phases of the SSC, as de ned by the WHO. Of the remaining 12 observed surgeries, 9 surgeries completed the last phase at the correct time. It was also observed that only in 2 surgeries all the phases of the SSC were read aloud to the team and that, in 7 surgeries, several items were read aloud and answered but no one was checking the SSC, only after the end of the phase. The observational study results disclose that several health professionals do not meet with rules of the WHO manual. This study demonstrates that it is urgent to change the mindset of health professionals, and that di erent features in the SSC may be useful to make it more easy to use. With the results of the observational study, a SSC application proposal was developed with new functionalities to improve and aid the health professional in its use. In this application the user can chose between a SSC already created to a speci c surgery or to create a new SSC, adding and adapting some questions from the WHO standard. To create a new SSC, the application is connected to an online questionnaire builder (JotForm). The choice for this online questionnaire builder went through three essential characteristics: number of types of questions, mainly checkbox, radio button and text; the possibility of to create sections inside sections and the API. In addition, in this proposal the improvements are focused in forcing the user to focus in the work ow of the SSC and to save the input timestamps and any actions made by them. Therefore, the following features was implemented to achieve that goal: display one item of the SSC at a time; display the stage where the SSC is; do not allow going back to the previous step; do not allow going forward to the next item if the current is not lled; do not allow going forward to the next item if the time it took to ll the item was too short and log any action made by the user.
Resumo:
Adhesively bonded techniques are an attractive option to repair aluminium structures, compared to more traditional methods. Actually, as a result of the improvement in the mechanical characteristics of adhesives, adhesive bonding has progressively replaced the traditional joining methods. There are several bonded repair configurations, as single-strap, double-strap and scarf. Compared with strap repairs, scarf repairs have the advantages of a higher efficiency and the absence of aerodynamic disturbance. The higher efficiency is caused by the elimination of the significant joint eccentricities of strap repairs. Moreover, stress distributions along the bond length are more uniform, due to tapering of the scarf edges. The main disadvantages of this technique are the difficult machining of the surfaces, associated costs and requirement of specialised labour. This work reports on an experimental and numerical study of the tensile behaviour of two-dimensional (2D) scarf repairs of aluminium structures bonded with the ductile epoxy adhesive Araldite® 2015. The numerical analysis, by Finite Elements (FE), was performed in Abaqus® and used cohesive zone models (CZM) for the simulation of damage onset and growth in the adhesive layer, thus enabling the strength prediction of the repairs. A parametric study was performed on the scarf angle (α) and different configurations of external reinforcement (applied on one or two sides of the repair, and also different reinforcement lengths). The obtained results allowed the establishment of design guidelines for repairing, showing that the use of external reinforcements enables increasing α for equal strength recovery, which makes the repair procedure easier. The numerical technique was accurate in predicting the repairs’ strength, enabling its use for design and optimisation purposes.
Resumo:
Os Mercados Eletrónicos atingiram uma complexidade e nível de sofisticação tão elevados, que tornaram inadequados os modelos de software convencionais. Estes mercados são caracterizados por serem abertos, dinâmicos e competitivos, e constituídos por várias entidades independentes e heterogéneas. Tais entidades desempenham os seus papéis de forma autónoma, seguindo os seus objetivos, reagindo às ocorrências do ambiente em que se inserem e interagindo umas com as outras. Esta realidade levou a que existisse por parte da comunidade científica um especial interesse no estudo da negociação automática executada por agentes de software [Zhang et al., 2011]. No entanto, a diversidade dos atores envolvidos pode levar à existência de diferentes conceptualizações das suas necessidades e capacidades dando origem a incompatibilidades semânticas, que podem prejudicar a negociação e impedir a ocorrência de transações que satisfaçam as partes envolvidas. Os novos mercados devem, assim, possuir mecanismos que lhes permitam exibir novas capacidades, nomeadamente a capacidade de auxiliar na comunicação entre os diferentes agentes. Pelo que, é defendido neste trabalho que os mercados devem oferecer serviços de ontologias que permitam facilitar a interoperabilidade entre os agentes. No entanto, os humanos tendem a ser relutantes em aceitar a conceptualização de outros, a não ser que sejam convencidos de que poderão conseguir um bom negócio. Neste contexto, a aplicação e exploração de relações capturadas em redes sociais pode resultar no estabelecimento de relações de confiança entre vendedores e consumidores, e ao mesmo tempo, conduzir a um aumento da eficiência da negociação e consequentemente na satisfação das partes envolvidas. O sistema AEMOS é uma plataforma de comércio eletrónico baseada em agentes que inclui serviços de ontologias, mais especificamente, serviços de alinhamento de ontologias, incluindo a recomendação de possíveis alinhamentos entre as ontologias dos parceiros de negociação. Este sistema inclui também uma componente baseada numa rede social, que é construída aplicando técnicas de análise de redes socias sobre informação recolhida pelo mercado, e que permite melhorar a recomendação de alinhamentos e auxiliar os agentes na sua escolha. Neste trabalho são apresentados o desenvolvimento e implementação do sistema AEMOS, mais concretamente: • É proposto um novo modelo para comércio eletrónico baseado em agentes que disponibiliza serviços de ontologias; • Adicionalmente propõem-se o uso de redes sociais emergentes para captar e explorar informação sobre relações entre os diferentes parceiros de negócio; • É definida e implementada uma componente de serviços de ontologias que é capaz de: • o Sugerir alinhamentos entre ontologias para pares de agentes; • o Traduzir mensagens escritas de acordo com uma ontologia em mensagens escritas de acordo com outra, utilizando alinhamentos previamente aprovados; • o Melhorar os seus próprios serviços recorrendo às funcionalidades disponibilizadas pela componente de redes sociais; • É definida e implementada uma componente de redes sociais que: • o É capaz de construir e gerir um grafo de relações de proximidade entre agentes, e de relações de adequação de alinhamentos a agentes, tendo em conta os perfis, comportamento e interação dos agentes, bem como a cobertura e utilização dos alinhamentos; • o Explora e adapta técnicas e algoritmos de análise de redes sociais às várias fases dos processos do mercado eletrónico. A implementação e experimentação do modelo proposto demonstra como a colaboração entre os diferentes agentes pode ser vantajosa na melhoria do desempenho do sistema e como a inclusão e combinação de serviços de ontologias e redes sociais se reflete na eficiência da negociação de transações e na dinâmica do mercado como um todo.