24 resultados para Strategic interaction
Resumo:
Electricity markets are complex environments, involving a large number of different entities, with specific characteristics and objectives, making their decisions and interacting in a dynamic scene. Game-theory has been widely used to support decisions in competitive environments; therefore its application in electricity markets can prove to be a high potential tool. This paper proposes a new scenario analysis algorithm, which includes the application of game-theory, to evaluate and preview different scenarios and provide players with the ability to strategically react in order to exhibit the behavior that better fits their objectives. This model includes forecasts of competitor players’ actions, to build models of their behavior, in order to define the most probable expected scenarios. Once the scenarios are defined, game theory is applied to support the choice of the action to be performed. Our use of game theory is intended for supporting one specific agent and not for achieving the equilibrium in the market. MASCEM (Multi-Agent System for Competitive Electricity Markets) is a multi-agent electricity market simulator that models market players and simulates their operation in the market. The scenario analysis algorithm has been tested within MASCEM and our experimental findings with a case study based on real data from the Iberian Electricity Market are presented and discussed.
Resumo:
The restructuring of electricity markets, conducted to increase the competition in this sector, and decrease the electricity prices, brought with it an enormous increase in the complexity of the considered mechanisms. The electricity market became a complex and unpredictable environment, involving a large number of different entities, playing in a dynamic scene to obtain the best advantages and profits. Software tools became, therefore, essential to provide simulation and decision support capabilities, in order to potentiate the involved players’ actions. This paper presents the development of a metalearner, applied to the decision support of electricity markets’ negotiation entities. The proposed metalearner executes a dynamic artificial neural network to create its own output, taking advantage on several learning algorithms implemented in ALBidS, an adaptive learning system that provides decision support to electricity markets’ players. The proposed metalearner considers different weights for each strategy, depending on its individual quality of performance. The results of the proposed method are studied and analyzed in scenarios based on real electricity markets’ data, using MASCEM - a multi-agent electricity market simulator that simulates market players’ operation in the market.
Resumo:
This article describes a study that investigated the main strategic drivers that influence the implementation of sustainability/social responsibility programs. An online survey was administered to managers of Portuguese organizations with certified management systems. The findings suggest that the implementation of such programs is mainly correlated to: 1.) the approach to understanding and working toward the satisfaction of the community’s needs (in the broad sense of social responsibility); 2.) how systematically sustainability within the organization is identified and managed (e.g., pollution prevention, improved environmental performance, and compliance with the applicable environmental laws); and 3.) the degree to which the organization tries to understand the needs of the employees and works toward satisfying them. In addition to the survey, five interviews with top managers of the surveyed organizations provided some useful insights. There was no consensus on the meaning of sustainability and social responsibility: some described it as an instrumental approach for obtaining better organizational results, while others regarded it as the right thing to do (i.e., it is values driven). In all cases, however, the managers supported a kind of umbrella construct under which different size corporations use different models (for example, the Dow Jones Sustainability Index (DJSI), Global Reporting Initiative (GRI), ISO 14001 environmental management systems), although some managers reported that they simply do not know what to do. All of those surveyed agreed that the lack of a systematic approach could represent a major threat to their organization, making them willing to pay more attention and take more action on the issue of sustainability. An additional suggestion made by managers was to change from a triple bottom line (economic dimension, environmental dimension, social equity dimension) to a quadruple bottom line by adding another dimension: personal and family happiness. This fourth dimension was recognized by the Greek philosopher/thinker Aristotle (384-322 BCE) who thought of happiness as the highest good (virtue) and ultimate goal and purpose of life, achieved through living well, in harmony. Such harmony suggests a balance and a lack of excess—in other words a sustainable existence.
Resumo:
We report an optical sensor based on localized surface plasmon resonance (LSPR) to study small-molecule protein interaction combining high sensitivity refractive index sensing for quantitative binding information and subsequent conformation-sensitive plasmon-activated circular dichroism spectroscopy. The interaction of α-amylase and a small-size molecule (PGG, pentagalloyl glucose) was log concentration-dependent from 0.5 to 154 μM. In situ tests were additionally successfully applied to the analysis of real wine samples. These studies demonstrate that LSPR sensors to monitor small molecule–protein interactions in real time and in situ, which is a great advance within technological platforms for drug discovery.
Resumo:
Astringency is an organoleptic property of beverages and food products resulting mainly from the interaction of salivary proteins with dietary polyphenols. It is of great importance to consumers, but the only effective way of measuring it involves trained sensorial panellists, providing subjective and expensive responses. Concurrent chemical evaluations try to screen food astringency, by means of polyphenol and protein precipitation procedures, but these are far from the real human astringency sensation where not all polyphenol–protein interactions lead to the occurrence of precipitate. Here, a novel chemical approach that tries to mimic protein–polyphenol interactions in the mouth is presented to evaluate astringency. A protein, acting as a salivary protein, is attached to a solid support to which the polyphenol binds (just as happens when drinking wine), with subsequent colour alteration that is fully independent from the occurrence of precipitate. Employing this simple concept, Bovine Serum Albumin (BSA) was selected as the model salivary protein and used to cover the surface of silica beads. Tannic Acid (TA), employed as the model polyphenol, was allowed to interact with the BSA on the silica support and its adsorption to the protein was detected by reaction with Fe(III) and subsequent colour development. Quantitative data of TA in the samples were extracted by colorimetric or reflectance studies over the solid materials. The analysis was done by taking a regular picture with a digital camera, opening the image file in common software and extracting the colour coordinates from HSL (Hue, Saturation, Lightness) and RGB (Red, Green, Blue) colour model systems; linear ranges were observed from 10.6 to 106.0 μmol L−1. The latter was based on the Kubelka–Munk response, showing a linear gain with concentrations from 0.3 to 10.5 μmol L−1. In either of these two approaches, semi-quantitative estimation of TA was enabled by direct eye comparison. The correlation between the levels of adsorbed TA and the astringency of beverages was tested by using the assay to check the astringency of wines and comparing these to the response of sensorial panellists. Results of the two methods correlated well. The proposed sensor has significant potential as a robust tool for the quantitative/semi-quantitative evaluation of astringency in wine.
Resumo:
We consider a trade policy model, where the costs of the home firm are private information but can be signaled through the output levels of the firm to a foreign competitor and a home policymaker. We compute the separating equilibrium and the Bayesian Nash equilibrium, and we compare the subsidies, firms’ expected profits and home government’s welfare in both equilibria, for different values of the own price effect parameter.
Resumo:
The use of buffers to maintain the pH within a desired range is a very common practice in chemical, biochemical and biological studies. Among them, zwitterionic N-substituted aminosulfonic acids, usually known as Good’s buffers, although widely used, can complex metals and interact with biological systems. The present work reviews, discusses and updates the metal complexation characteristics of thirty one commercially available buffers. In addition, their impact on biological systems is also presented. The influences of these buffers on the results obtained in biological, biochemical and environmental studies, with special focus on their interaction with metal ions, are highlighted and critically reviewed. Using chemical speciation simulations, based on the current knowledge of the metal–buffer stability constants, a proposal of the most adequate buffer to employ for a given metal ion is presented.
Resumo:
O presente trabalho de projeto resulta de um estudo dos espaços de participação, dos alunos dos 2.º e 3.º ciclo do ensino básico, na vida da escola, permitindo a construção de um dispositivo de intervenção, que pretende implementar ações estratégicas que visem a ampliação desses espaços de participação. O seu desenvolvimento teórico assenta na necessidade da revitalização da cultura democrática participativa, através de uma maior e melhor participação. Neste campo, a escola, como lugar de interação quotidiana dos seus alunos, tem um papel importante a desempenhar na capacitação de uma participação ativa. Para tal urge a necessidade de implementação de ações estratégicas, em coerência com os documentos estruturantes da organização e de todos os seus órgãos de administração e gestão, de forma a instituir a mudança e a inovação na cultura de trabalho como um dos aspetos chave para o sucesso organizacional da escola. O trabalho de projeto foi realizado numa escola pública dos 2.º e 3.º ciclos e a amostra do estudo, foi composta por 401 alunos dos 2.º e 3.º ciclos e 31 professores Diretores de Turma. Os instrumentos de recolha de dados foram dois inquéritos por questionário, um para aplicar aos alunos, e outro aos Diretores de Turma, e a análise de conteúdo dos documentos orientadores da escola. Os resultados mostraram que os alunos possuem uma débil participação na vida da escola, quer ao nível dos documentos orientadores, quer na sua representação nos diferentes órgãos. No plano de ação, é apresentado um conjunto de propostas, que pretendem constituir-se como um dispositivo para colmatar esta debilidade.
Resumo:
O trabalho aqui apresentado é a Dissertação da minha Tese do curso de Mestrado em Engenharia Eletrotécnica e de Computadores do ISEP, realizada em parceria com o INESC TEC. O trabalho consiste no desenvolvimento de um sistema avançado de interação entre homem-robô, usando ferramentas de software livres e de domínio público e hardware pouco dispendioso e facilmente acessível. Pretende-se que o sistema desenvolvido possa ser adotado por pequenas ou micro empresas, daí a restrição monetária. Este tipo de empresas tem, por norma, uma capacidade de investimento pequena, e ficam impossibilitadas de aceder a este tipo de sistemas automatizados se estes forem caros. No entanto, o robô continua a ser um componente fundamental, sendo dispendioso. Os trabalhos realizados pelos sistemas robóticos podem por um lado, ser repetitivos sem necessidade de grandes ajustes; por outro lado, o trabalho a realizar pode ser bastante diverso, sendo necessários bastantes ajustes com (possivelmente) programação do robô. As empresas podem não ter disponível mão-de-obra qualificada para realização da programação do robô. Pretende-se então um sistema de “ensino” que seja simples e rápido. Este trabalho pretende satisfazer as necessidades de um sistema de interação homem-robô intuitivo mesmo para operadores que não estejam familiarizados com a robótica. Para simplificar a transferência de informação da tarefa a desempenhar pelo sistema robótico é usado um sistema de infravermelhos para delinear a operação a desempenhar, neste caso concreto uma operação de soldadura. O operador usa um apontador com marcadores, a posição destes marcadores é detetada usando duas câmaras para permitir o posicionamento tridimensional no espaço. As câmaras possuem filtros infravermelhos para separar o espectro de luz. Para o controlo do sistema e interface com o robô é usado um computador de baixos recursos computacionais e energéticos, e também de baixo custo. O sistema desenvolvido é portanto computacionalmente leve para poder ser executado neste computador.