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In this contribution in honour of Paul Busch, we criticise the claims of many expositions that the time-energy uncertainty principle allows both a violation of energy conservation, and particle creation, provided that this happens for a sufficiently short time. But we agree that there are grains of truth in these claims: which we make precise and justify using perturbation theory., Forthcoming in Journal of Physics: Conference Proceedings, Mathematical Foundations of Quantum Mechanics in Memoriam Paul Busch

Reducing energy consumption is a major challenge for "energy-intensive" industries such as papermaking. A commercially viable energy saving solution is to employ data-based optimization techniques to obtain a set of "optimized" operational settings that satisfy certain performance indices. The difficulties of this are: 1) the problems of this type are inherently multicriteria in the sense that improving one performance index might result in compromising the other important measures; 2) practical systems often exhibit unknown complex dynamics and several interconnections which make the modeling task difficult; and 3) as the models are acquired from the existing historical data, they are valid only locally and extrapolations incorporate risk of increasing process variability. To overcome these difficulties, this paper presents a new decision support system for robust multiobjective optimization of interconnected processes. The plant is first divided into serially connected units to model the process, product quality, energy consumption, and corresponding uncertainty measures. Then multiobjective gradient descent algorithm is used to solve the problem in line with user's preference information. Finally, the optimization results are visualized for analysis and decision making. In practice, if further iterations of the optimization algorithm are considered, validity of the local models must be checked prior to proceeding to further iterations. The method is implemented by a MATLAB-based interactive tool DataExplorer supporting a range of data analysis, modeling, and multiobjective optimization techniques. The proposed approach was tested in two U.K.-based commercial paper mills where the aim was reducing steam consumption and increasing productivity while maintaining the product quality by optimization of vacuum pressures in forming and press sections. The experimental results demonstrate the effectiveness of the method.

Energy conservation has become an increasingly important issue for all sectors, particularly in industry. Therefore, the thermal performance of insulation systems and their influence on heat loss/gain in various applications in addition to economic considerations have received increased attention in recent years. In this study, a literature review of papers that addressed the optimum economic thickness of the thermal insulation on a pipe or duct with different geometries used in various industries was carried out The studies related to determining the critical insulation thickness for different geometries including circular shapes were investigated. The heat transfer equations, the basic results, the optimization procedures and the economic analysis methods used in the studies were presented comparatively. Additionally, a practical application example based on optimizing the insulation thickness on a pipe was performed, and the effective parameters of the optimum thickness were investigated.

Orientador: Gilberto de Martino Jannuzzi Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica Resumo: Esta tese versa sobre a reciclagem energética do resíduo domiciliar urbano no estado de São Paulo. A pesquisa engloba uma análise da situação do lixo no estado; um estudo sobre a viabilidade da recuperação energética pela reciclagem do papel e do alumínio contido no resíduo descartado; e uma avaliação da capacidade de geração de energia elétrica, com base na incineração da parte do lixo sujeita a este processo. No trabalho são apresentados os resultados dos estudos e avaliações realizadas, abordando questões relativas à quantidade e a composição do lixo, principalmente quanto ao papel e ao alumínio; os programas de reciclagem de materiais existentes; a quantidade de material reciclável e o potencial energético recuperável O cálculo deste potencial, leva em consideração a possibilidade de incineração (com geração de eletricidade) de parte do lixo. Como complemento são feitos comentários sobre as vantagens diretas e indiretas da reciclagem energética do lixo Abstract: This thesis discusses the energy recycling of the urban waste in the state of São Paulo, Brazil. The research includes an analyses of the problem of urban waste in the state; a study of the viability of energy recovery by recycling paper and aluminum contained in the urban waste; and an evaluation of the electricity generation capacity related to waste incineration. The results of the studies and the evaluation detected are presented considering the waste amount and composition, mainly the paper and the aluminum; the existent programs for recycling; the amount of materials available for recycling; and the energy savings potential of the materials disposed in sanitary landfills.The calculations of this potential take into account the incineration possibility(with electricity generation) ofpart ofthe waste. Comments on the direct and indirect advantages of the energy recycling of the waste are made Doutorado Doutor em Planejamento de Sistemas Energéticos