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A survey of the development and experience with knowledge-based systems applied to power systems in Europe, including expert systems used in operation, is presented. The technical aspects of power system operation are briefly reviewed, the role of computers in power systems is discussed, and the motivation for investigating knowledge-based applications in this context is identified. The structure of the research and industrial organizations involved in the development and implementation is described, and the characteristics of main application areas are discussed. Future expert system development and implementation are discussed. >

Capture of trace amounts (parts per trillion or ppt level) of 90Sr from highly Na+-rich (5 M or 115 000 parts per million) liquid wastes produced from reprocessing of spent nuclear fuel rods is crucial for continuous operation of nuclear power plants.

The growing global awareness of social and environmental issues has led investors to prioritize sustainable investments. This study examines the relationship between ten Islamic and conventional sector indices, which include stocks screened for environmental, social, and governance (ESG) factors, across three energy-related fields: renewable energy, energy efficiency, and oil equipment and services. Using a quantile cross-spectral approach, this research finds a high level of long-term synchronization among all energy-related sectors and indices. However, as markets shift from bearish to bullish, the current relationship between energy-related sectors and Islamic and conventional indices weakens. To support the findings in this research and investigate potential financial implications, this investigation applies a causality-in-quantiles approach. The research in this study shows a bidirectional causal relationship between conventional and Islamic indices, particularly in the energy efficiency sector during bearish market conditions. At lower tails, ESG market indices are found to cause renewable energy products, suggesting a hedging mechanism. The findings of this study assert that investments that do not possess any ESG shortcomings are imperative for effectively bolstering renewable energy companies and fostering opportunities for energy efficiency. These conclusions hold considerable ramifications for energy policymakers as they strive to devise more robust financial mechanisms that can provide substantial support to the burgeoning green sector.

Biomethane is a flexible energy vector that can be used as a renewable fuel for both the heat and transport sectors. Recent EU legislation encourages the production and use of advanced, third generation biofuels with improved sustainability for future energy systems. The integration of technologies such as anaerobic digestion, gasification, and power to gas, along with advanced feedstocks such as algae will be at the forefront in meeting future sustainability criteria and achieving a green gas supply for the gas grid. This paper explores the relevant pathways in which an integrated biomethane industry could potentially materialise and identifies and discusses the latest biotechnological advances in the production of renewable gas. Three scenarios of cascading biomethane systems are developed.

Abstract We first describe the static thermo-mechanical loadings of some important structures due to accidental situations. We calculate the behaviour of these structures by several methods; elastic and plastic analysis, and limit design. We show the interest of this last method.

Le marquage alimentaire géographique a souvent été perçu comme une forme de protection contre les copies et, d'une manière générale, la mauvaise qualité. Ce qu'il a été en son temps. Mais on n'a jamais bien perçu, qu'en réalité, derrière ce système, ce n'était pas le passé, la "tradition", l'histoire qui étaient mis en valeur. Ce système a joué le rôle d'une forme de capitalisation des savoir-faire, formulés par le législateur, pour inscrire le produit dans la durée, autant dans le passé que dans le futur. Comment la géographie a-t-elle pu jouer ce rôle capitalistique ? Par le jeu des échelles. En agrandissant les marchés, en mondialisant les produits, la qualité a été renforcée par la rareté, l’unicité (qu'il a fallu parfois combattre, les Champenois le savent bien) et, finalement, l’inaliénabilité des produits et des mets. Ainsi, la géographie qui devait se fondre dans le temps tourbillonnant du capitalisme et du libéralisme, est-elle devenue une des marques de fabrique les plus sûres qui soient. Geographical food labeling was often perceived as a form of protection against counterfeiting and, generally speaking, lower quality. Which was the case in its time. However, it was never well understood that in reality, behind this system, it was not the past, the “tradition, the history that were emphasized. This system has played the role of a form of capitalization of know-how, as expressed by the regulator, to consider the products in the long-term perspective, as much the past than the future. How geography managed to play this capitalizing role? By the means of scales. By enlarging markets, globalizing products, it was reinforced by its scarcity, its uniqueness (which sometimes had to be fought, the Champagne producers know it well) and finally its inalienability. Thus, geography, which was to blend in the whirl of capitalism and liberalism, became one of the most trustworthy trade marks.

Phosphogypsum (PG) is the solid waste product of phosphate fertilizer production and is characterized by high concentrations of salts, heavy metals, and certain natural radionuclides. The work reported in this paper examined the influence of PG amendment on soil physicochemical proprieties, along with its potential impact on several physiological traits of sunflower seedlings grown under controlled conditions. Sunflower seedlings were grown on agricultural soil substrates amended with PG at rates of 0, 2.5, and 5 %. The pH of the soil decreased but electrical conductivity and organic matter, calcium, phosphorus, sodium, and heavy metal contents increased in proportion to PG concentration. In contrast, no variations were observed in magnesium content and small increases were recorded in potassium content. The effects of PG on sunflower growth, leaf chlorophyll content, nutritional status, osmotic regulator content, heavy metal accumulation, and antioxidative enzymes were investigated. Concentrations of trace elements in sunflower seedlings grown in PG-amended soil were considerably lower than ranges considered phytotoxic for vascular plants. The 5 % PG dose inhibited shoot extension and accumulation of biomass and caused a decline in total protein content. However, chlorophyll, lipid peroxidation, proline and sugar contents, and activities of antioxidant enzymes such as superoxide dismutase and catalase increased. Collectively, these results strongly support the hypothesis that enzymatic antioxidation capacity is an important mechanism in tolerance of PG salinity in sunflower seedlings.

This paper focuses on mixed [Formula: see text] fuzzy maximum power point tracking (MPPT) of photovoltaic (PV) system under asymmetric saturation and variations in climatic conditions. To maximize the power from the PV panel array, the DC–DC boost converter is controlled by its duty ratio which is practically saturated between 0 and 1. MPPT based on conventional control presents the problems of oscillations around maximum power point (MPP) and divergence under rapid climatic changes. In order to attenuate the effect of atmospheric condition variation and take into account asymmetric saturation of the duty ratio, we propose a novel robust saturated controller based on both [Formula: see text] performances and Takagi-Sugeno (T-S) representation of PV-boost nonlinear system. Within this approach, the nonlinear PV-boost system and its reference are first described by T-S fuzzy models. Second, the saturation effect is represented by a polytopic model. Then, a fuzzy integral state feedback controller is designed to achieve stable MPPT control. Based on Lyapunov function, the mixed [Formula: see text] stabilization conditions are derived in terms of linear matrix inequalities (LMIs). The optimization of the attraction domain of closed-loop system is solved as a convex optimization problem in LMI terms. Finally, the efficiency of the proposed controller under irradiance and temperature variations is demonstrated through the simulation results. The comparison with some existing controllers shows an improvement of MPPT control performance in terms of power extraction.