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951.
952.
基于神经网络的短期电价预测 总被引：5，自引：0，他引：5
利用系统旋转备用、历史负荷和清算电价对未来时段电价的影响来进行电价预测。以澳大利亚昆士兰州电力市场为背景,采用神经网络的方法,建立了提前1天电力市场清算电价短期预测模型。模型为3层BP神经网络结构,并采用昆士兰州电力市场1998年的电价数据进行了训练和预测分析,结果表明该模型具有良好的预测效果。 相似文献
953.
《Food Control》2015
The aim of this study was to investigate the occurrence of aflatoxin B1 (AFB1) and ochratoxin A (OTA) in different traditional meat products circulating on Croatian markets, produced by a large number of households situated in different Croatian regions. The study involved a total of 410 samples of traditional pork meat products in terms of hams (n = 105), dry fermented sausages (n = 208), bacon (n = 62) and cooked sausages (n = 35), collected over four years period (2011–2014). Mycotoxin concentrations were quantified and confirmed using validated immunoassay method (ELISA) and high performance liquid chromatography with fluorescence detection (HPLC-FLD), respectively. The maximal observed OTA level in the fermented sausages and hams was around 5 times (5.10 μg/kg) to 10 times (9.95 μg/kg) higher than the maximal recommended level (1 μg/kg) stipulated for pork products in some EU countries. AFB1 levels found in any given meat product analysed within this frame were not significantly higher (p > 0.05) than the applied method limit of detection. The results showed an occasional mycotoxin contamination of traditional meat products, especially that by OTA, pointing that to avoid such contamination meat and meat products on households should be produced and processed under standardised and well-controlled conditions. 相似文献
954.
This paper suggests that transdisciplinarity is rising as a powerful epistemic strategy for research in technology-related fields such as engineering. Though this topic has been approached from a philosophical perspective, we know little about the actual shape that transdisciplinarity might take in research and action. How is transdisciplinarity operationalized in research and professional practice? As a case study, we report an assessment study of communication modes and content used by engineering students in a special project-course, Robotics for Theater, focused on the planning and construction of a robot from scratch, to support theatric production as actor and prop. Our assessment tools were based on ethnographic research and included questionnaires, journals, and students' expressions of their views on the communication and learning processes. Analysis of the case study of the Robotics for Theater project revealed that: 1. Resource mobilization was fostered by the role of the advisor as information facilitator and “weak tie” in the network, and also by the frequent informal contacts among the students in the team. 2. Innovation was fostered by intra-team trust. The strong friendship and teaming experience of the group were critical for effective team dynamics. 3. Probably due to time constraints, the field of theater did not become a fundamental reference of the project, contrary to plans. 4. Time constraints and technical difficulties in implementation inhibited progress. 5. Informal meetings were crucial in the progression of design and implementation. 相似文献
955.
Lewis M. Fulton Lee R. Lynd Alexander Krner Nathanael Greene Luke R. Tonachel 《Biofuels, Bioproducts and Biorefining》2015,9(5):476-483
The question of whether the world needs biofuels is approached by examining the feasibility of doing without them. Even with aggressive reductions in travel growth, shifts to mass transport modes, strong efficiency improvements, and deep market penetration by vehicles running on electricity and hydrogen, there remains a large demand for dense liquid fuels in 2050 (80% of transportation fuel) and even in 2075 (50%). This demand is due largely to aviation, ocean shipping, and long‐haul trucking. Acknowledging the significant uncertainties involved in such projections and the challenges faced by all candidate technologies and fuels, we conclude that it will likely be difficult to achieve a low‐carbon transport sector without widespread use of biofuels, and that aggressive efforts to develop sustainable, low‐carbon biofuels alongside other options are warranted. © 2015 Society of Chemical Industry and John Wiley & Sons, Ltd 相似文献
956.
Significant efforts have been made in Lithuania to enhance the utilization of bioenergy since the early 1990s. While opportunities are large and signs of development visible, bioenergy still needs technical, institutional and policy-related support for further development side by side with other industries. This paper discusses the existing bioenergy potential in Lithuanian forests, biofuels market formation in the region and possible roads to boost development. The retrofitting of heat plants, forest management and policies are reviewed as a way to identify opportunities to promote bioenergy in the country. It is shown that the interplay between national and regional forces can promote technological and managerial improvements in the forest industry while also enhancing the biomass supply and sustainability of bioenergy systems. 相似文献
957.
958.
This paper reports a study on the importance of the training criteria for wind power forecasting and calls into question the generally assumed neutrality of the ‘goodness’ of particular forecasts. The study, focused on the Spanish Electricity Market as a representative example, combines different training criteria and different users of the forecasts to compare them in terms of the benefits obtained. In addition to more classical criteria, an information theoretic learning training criterion, called parametric correntropy, is introduced as a means to correct problems detected in other criteria and achieve more satisfactory compromises among conflicting criteria, namely forecasting value and quality. We show that the interests of wind farm owners may lead to a preference for biased forecasts, which may be in conflict with the larger needs of secure operating policies. The ideas and conclusions are supported by results from three real wind farms. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
959.
This paper presents a Supply Curve Bidding (SCB) approach that complies with the notion of the Standard Market Design (SMD) in electricity markets. The approach considers the demand-side option and Locational Marginal Pricing (LMP) clearing. It iteratively alters Supply Function Equilibria (SFE) model solutions, then choosing the best bid based on market-clearing LMP and network conditions. It has been argued that SCB better benefits suppliers compared to fixed quantity-price bids. It provides more flexibility and better opportunity to achieving profitable outcomes over a range of demands. In addition, SCB fits two important criteria: simplifies evaluating electricity derivatives and captures smooth marginal cost characteristics that reflect actual production costs. The simultaneous inclusion of physical unit constraints and transmission security constraints will assure a feasible solution. An IEEE 24-bus system is used to illustrate perturbations of SCB in constrained power networks within the framework of SDM. By searching in the neighborhood of SFE model solutions, suppliers can obtain their best bid offers based on market-clearing LMP and network conditions. In this case, electricity producers can derive their best offering strategy both in the power exchange and the long-term contractual markets within a profitable, yet secure electricity market. 相似文献
960.
期货组合套期保值的效率分析 总被引：4，自引：0，他引：4
对期货市场组合套期保值策略和保值风险进行了分析,给出组合套期保值率的最小二乘估计和保值风险的估计,研究组合套期保值的效率和参加组合的每种期货的效率,并给出了它们的估计量。这样可以用估计量度量组合套期保值降低风险的程度和每种期货在组合套期保值中贡献的大小。使套期保值的理论得到进一步发展,以使投资者可以更好地运用套期保值策略。 相似文献