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91.
This paper replicates the Diebold and Yilmaz (2012) study on the connectedness of the commodity market and three other financial markets: the stock market, the bond market, and the FX market, based on the Generalized Forecast Error Variance Decomposition, GEFVD. We show that the net spillover indices (of directional connectedness), used to assess the net contribution of one market to overall risk in the system, are sensitive to the normalization scheme applied to the GEFVD. We show that, considering data generating processes characterized by different degrees of persistence and covariance, a scalar-based normalization of the Generalized Forecast Error Variance Decomposition is preferable to the row normalization suggested by Diebold and Yilmaz since it yields net spillovers free of sign and ranking errors. 相似文献
92.
FUMITOSHI NOMIYAMA TAKUMA MURAKAMI JOJI ASAI HIROTAKA TAKANO JUNICHI MURATA 《Electrical Engineering in Japan》2016,196(3):13-21
A method is proposed for forecasting global solar radiation. The method is based on weather information using binary trees and factor analysis. The feature of this method is that it is possible to use a simple linear forecasting equation. The method has been tested on meteorological and global solar radiation data obtained at several observation sites, and the results show that it is a promising means of maintaining the balance between demand and supply of electric power in power systems of the near future with a large number of photovoltaic systems installed. 相似文献
93.
针对广东省基层三防机构、人员落实不到位,应对台风暴雨洪涝灾害能力较弱等突出问题,通过利用移动互联网、地理信息、短信发送、语音外呼等技术构建统一平台,以集中式部署的方式开展预警信息发布平台建设,实现省、市、县、镇、村五级三防部门的责任人和预案管理、预警信息发布、语音外呼等功能,提高乡镇三防部门灾害应急响应和协调处置能力。 相似文献
94.
针对新疆克州塔日勒嘎水电站泄洪冲沙闸闸室置于不同强度地基基础上的情况,设计了简单易得的扩大回填方案以处理基础,通过三维有限元计算和现场的实际监测,结果表明:这种基础处理方案安全可靠,有一定的实用价值。 相似文献
95.
随着城镇化进程的加快,原有的郊区湖泊成为城市发展的优先区域,对湖泊的治理,从防洪、水资源利用、景观娱乐等功能都提出了新的要求。一方面城市新区要求城市防洪标准相应提高,要求湖泊有较大的防洪调蓄能力,而另一方面城市建设亲水、乐水的原则和思路,要求减小湖泊水位的变幅,同时协调好湖泊治理及调度运行多目标之间的矛盾。本文以黄石大冶湖防洪调度水位为例,通过对湖泊起排水位、防洪目标水位、圩垸分洪、扩建外排泵站等多种解决方案的研究,综合考虑实际条件以及经济性等因素,提出了通过多种手段综合解决问题的思路,以供其他湖泊治理及调度水位研究借鉴。 相似文献
96.
结合广州从化温泉养生谷商务会议区施工图设计,从场地防洪设计、道路交通分析、竖向规划控制、工程管线综合4个方面进行具体论述,对规划方案落实到施工图过程中起制约作用的环节进行控制,较好地解决了项目推进中遇到的因一系列不利条件带来的技术难题。 相似文献
97.
98.
汀溪灌区作为汀溪水库群的农业供水对象,其灌溉用水量的大小直接关系到汀溪水库群向翔安、同安两区的水资源供需平衡,甚至影响厦门市水资源配置方案。但由于灌溉面积和渠道功能发生变化,有必要进行洪水分析复核从而重新确定工程规模。本文对汀溪灌区总干渠洪水复核方法进行探讨,供参考。 相似文献
99.
It is estimated that Europe alone will need to add over 250,000 km of transmission capacity by 2050, if it is to meet renewable energy production goals while maintaining security of supply. Estimating the cost of new transmission infrastructure is difficult, but it is crucial to predict these costs as accurately as possible, given their importance to the energy transition. Transmission capacity expansion plans are often founded on optimistic projections of expansion costs. We present probabilistic predictive models of the cost of submarine power cables, which can be used by policymakers, industry, and academia to better approximate the true cost of transmission expansion plans. The models are both generalizable and well-specified for a variety of submarine applications, across a variety of regions. The best performing statistical learning model has slightly more predictive power than a simpler, linear econometric model. The specific decision context will determine whether the extra data gathering effort for the statistical learning model is worth the additional precision. A case study illustrates that incorporating the uncertainty associated with the cost prediction to calculate risk metrics - value-at-risk and conditional-value-at-risk - provides useful information to the decision-maker about cost variability and extremes. 相似文献
100.
M. Diakakis G. Deligiannakis K. Katsetsiadou Z. Antoniadis M. Melaki 《Urban Water Journal》2017,14(10):1065-1074
Urban flooding is a gradually increasing problem as the urban population expands into floodplains. In urban environments, flood vulnerability is significantly increased as a more concentrated population and assets makes flooding costly and challenging, in terms of impact estimation. This work focuses on mapping and classifying impacts after the catastrophic 2014 flood in Athens, Greece. The study proposes a method for classifying flood effects into four categories including: the natural and built environment, mobile objects and human population, organized in five classes of increasing severity, i.e. minor, weak, moderate, strong and extreme. Flood effects are grouped based on the qualitative nature of the recorded effects, allowing the development of an impact-severity map. Mapping of the 2014 flood effects indicated specific locations where the severity of impacts was distinctively higher than others, providing a holistic overview of the flood’s effects and highlighting the usefulness of the approach in future flood protection planning. 相似文献