On Kant's first insight into the problem of space dimensionality and its physical foundations

In this article it is shown that a careful analysis of Kant's "Thoughts on the True Estimation of Living Forces" leads to a conclusion that does not match the usually accepted interpretation of Kant's reasoning in 1747, according to which the Young Kant supposedly establishes a relationship between the tridimensionality of space and Newton's law of universal gravitation. Indeed, it is argued that this text does not yield a satisfactory explanation of space dimensionality, actually restricting itself to justify the tridimensionality of extension.Comment: 14 page

Business models for Energy Storage Systems

Recent commitments to reduce greenhouse gas emissions in the electricity industry associated with the electrification of segments of heat and transport sectors pose significant challenges of unprecedented proportions . The unique features of Energy Storage Systems (ESS) coupled with the flexibility of providing services to multiple sectors of the electricity industry, make it a key technology to tackle current and upcoming challenges in the electricity industry. Although ESS have the potential to support future system integration with large amounts of renewable generation, the potential value that ESS brings to stakeholder s and its associated economics are not well understood to date. In addition, further research is needed on its business model in various markets and system conditions, in particular in the value associated with each service or set of services. In this context, the conducted research has addressed ESS operational aspects when considering a multiple services portfolio provided to various stakeholders and sensitive to market and system conditions. New ESS operational frameworks together with a computationally efficient modelling framework are proposed for a better understanding of ESS business models. The novelty introduced with this work is associated with a multiple service business model for ESS which considers services to distribution network operators, system operators, low capacity value generation and participation in the energy market. In addition, the economic aspects of ESS considering various operating policies for maximum revenue is also investigated and enhances the understanding of ESS to develop appropriate market mechanisms and allow efficient deployment of ESS in the electricity industry.Open Acces

On the Physical Problem of Spatial Dimensions: An Alternative Procedure to Stability Arguments

Why is space 3-dimensional? The first answer to this question, entirely based on Physics, was given by Ehrenfest, in 1917, who showed that the stability requirement for n-dimensional two-body planetary system very strongly constrains space dimensionality, favouring 3-d. This kind of approach will be generically called "stability postulate" throughout this paper and was shown by Tangherlini, in 1963, to be still valid in the framework of general relativity as well as for quantum mechanical hydrogen atom, giving the same constraint for space{dimensionality. In the present work, before criticizing this methodology, a brief discussion has been introduced, aimed at stressing and clarifying some general physical aspects of the problem of how to determine the number of space dimensions. Then, the epistemological consequences of Ehrenfest's methodology are critically reviewed. An alternative procedure to get at the proper number of dimensions, in which the stability postulate - and the implicit singularities in three-dimensional physics - are not an essential part of the argument, is proposed. In this way, the main epistemological problems contained in Ehrenfest's original idea are avoided. The alternative methodology proposed in this paper is realized by obtaining and discussing the n-dimensional quantum theory as expressed in Planck's law, de Broglie relation and the Heisenberg uncertainty relation. As a consequence, it is possible to propose an experiment, based on thermal neutron diraction by crystals, to directly measure space dimensionality. Finally the distinguished role of Maxwell's electromagnetic theory in the determination of space dimensionality is stressed

Política energética no Brasil

ENERGY is an essential ingredient to life in modern society. The expansion of Brazil's energy infrastructure, both for production and consumption, will demand large investments. This, in turn, requires government planning of energy-related activities, which are usually implemented by the private sector. This presence is essential for: 1. Fulfilling society's demand for more and better energy services; 2. Stimulating participation in sustainable and enduring energy sources; 3. Prioritizing efficient energy use in order to disengage capital for more productive areas of the economy and to preserve the environment; 4. Using investment in energy as a source of jobs and a stimulus to domestic industries; 5. Incorporating foreign inputs into the energy portfolio when it is commercially and socially advantageous for Brazil - including the exportation of energy products and services; and 6. Generating energy from various sources to reduce the risk of eventual shortages, in keeping with the country's available energy reserves.ENERGIA é um ingrediente essencial para a vida na sociedade moderna. A ampliação da infra-estrututa energética do Brasil, tanto na sua produção como no consumo exigirá grandes investimentos. Daí a necessidade da presença do Governo no planejamento das atividades energéticas, que são geralmente implementados pela iniciativa privada. Esta presença é essencial para: 1. atender a demanda da sociedade por mais e melhores serviços de energia; 2. estimular a participação de fontes energéticas sustentáveis e duradouras; 3. priorizar o uso eficiente da energia para liberar capital aos setores mais produtivos da economia e preservar o meio ambiente; 4. utilizar o investimento em energia como fonte de geração de empregos e de estímulo à indústria nacional; 5. incorporar à matriz energética insumos importados quando isso resultar em vantagens comerciais e sociais ao país, inclusive através da abertura de exportação de produtos e serviços e, 6. produzir energia de diversas fontes, reduzindo o risco da eventual escassez de algumas delas de forma compatível com as reservas disponíveis no país

Learning control knowledge by observation in software agents

This thesis is the outcome of research on providing software agents with learning by observation capabilities. It presents an agent architecture that allows software agents to learn control knowledge by direct observation of the actions executed by expert agents while performing a task. The proposed architecture makes it possible for software agents to observe each other. It displays information that is essential for observation, such as the agent constituents and capabilities, the actions performed and the conditions holding for them. The displayed information is accessible to all agents that want to observe. The proposed approach combines two methods of learning from the observed data. The first one relies on the sequence which the actions were observed. The second one categorizes the information in the observed data and determines which set of categories the new problems belong. The two learning methods are incorporated into a learning process that covers all aspects of learning by observation such as the discovery and observation of experts, storage of the acquired information, learning and application of the acquired knowledge. The learning process also includes an evaluation of the agent’s progress which provides control over the decision to obtain new knowledge or apply the acquired knowledge to new problems. The process is extended with external feedback on the actions executed by the agent. The approach was tested on three different scenarios that show that learning by observation can be of key importance whenever agents sharing similar features want to learn from each other.Esta tese resulta da investigação da aplicação da aprendizagem por observação em agentes de software. A tese apresenta uma arquitetura que permite a agentes de software aprender mecanismos de controlo por observação direta das acções realizadas por agentes especialistas enquanto estes realizam uma tarefa. A arquitetura proposta permite que agentes de software se observem uns aos outros ao exibir informações que são essenciais para a observação, tais como os constituintes e as capacidades do agente, as ações realizadas e as condições existentes aquando a realização das mesmas. Esta informação é acessível a todos os agentes que queiram observar. A abordagem proposta combina dois métodos de aprendizagem. O primeiro baseia-se na sequência em que as ações foram observadas. O segundo categoriza a informação observada e determina o conjunto de categorias aos quais os novos problemas pertencem. Os dois métodos de aprendizagem são incorporados num processo de aprendizagem que cobre todos os aspetos da aprendizagem por observação tais como a descoberta e observação de especialistas, o armazenamento da informaçãao adquirida, a aprendizagem e a aplicação do conhecimento adquirido. O processo de aprendizagem inclui também uma avaliação do progresso do agente que controla a decisão de obter novo conhecimento ou de aplicar o conhecimento adquirido em novos problemas. O processo é alargado com feedback externo sobre as acões executadas. A abordagem foi testada em três diferentes cenários que mostram a importância da aprendizagem por observação em situações onde agentes que compartilham características semelhantes querem aprender uns com os outros.This thesis reports PhD research work, for the Doctoral Program on Information Science and Technology of ISCTE-Instituto Universitario de Lisboa. It is partially supported by Fundação para a Ciencia e a Tecnologia through the PhD Grant number SFRH/BD/44779/2008 and the Associated Laboratory number 12 - Instituto de Telecomunicações - PEst-OE/EEI/LA0008/2013

Prevalence and factors associated with frailty in an older population from the city of Rio de Janeiro, Brazil: the FIBRA-RJ Study

OBJECTIVE: Frailty syndrome can be defined as a state of vulnerability to stressors resulting from a decrease in functional reserve across multiple systems and compromising an individual's capacity to maintain homeostasis. The purpose of this study was to determine the prevalence of frailty and its association with social and demographic factors, functional capacity, cognitive status and self-reported comorbidities in a sample of community-dwelling older individuals who are clients of a healthcare plan. METHODS: We evaluated 847 individuals aged 65 years or older who lived in the northern area of the city of Rio de Janeiro, Brazil. The subjects were selected by inverse random sampling and stratified by gender and age. To diagnose frailty, we used the scale proposed by the Cardiovascular Health Study, which consisted of the following items: low gait speed, grip strength reduction, feeling of exhaustion, low physical activity and weight loss. The data were collected between 2009 and 2010, and the frailty prevalence was calculated as the proportion of individuals who scored positive for three or more of the five items listed above. To verify the association between frailty and risk factors, we applied a logistic regression analysis. RESULTS: The prevalence of frailty syndrome was 9.1% (95% confidence interval [CI], 7.3-11.3); 43.6% (95% CI, 40.3-47) of the individuals were considered robust, and 47.3% (95% CI 43.8-50.8) were considered pre-frail (

Estimating Regional Poverty Lines With Scarce Data: An Application to Brazilian Regions

The recent emphasis on fighting poverty in Brazil makes the determination of the size of the targeted population an important issue (What is the right poverty line? What is the real size of the poor population? How much money should be given to each poor family?). The application of poverty lines based on national income levels tends to produce important distortions at the regional level. Using data from a Household Expenditure Survey (HES) that covered some regions in Brazil, the paper develops and applies a methodology to define poverty lines for all regions and urban areas. These lines are based on nutritional requirements, thus avoiding the purchasing power parity problem, and take into account non-monetary income and in-kind consumption, aspects that are very important at the rural level. The HES results are matched with Census data, allowing for the estimation of rural and urban poverty lines for Brazilian regions.