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1.
《Energy Policy》2015
The low price of lead-acid, the most popular battery, is often used in setting cost targets for emerging energy storage technologies. Future cost reductions in lead acid batteries could increase investment and time scales needed for emerging storage technologies to reach cost-parity. In this paper the first documented model of cost reductions for lead-acid batteries is developed. Regression to a standard experience curve using 1989–2012 data yield a poor fit, with R2 values of 0.17 for small batteries and 0.05 for larger systems. To address this problem, battery costs are separated into material and residual costs, and experience curves developed for residual costs. Depending on the year, residual costs account for 41–86% of total battery cost. Using running-time averages to address volatility in material costs, a 4-year time average experience curve for residual costs yield much higher R2, 0.78 for small and 0.74 for large lead-acid batteries. The learning rate for residual costs in lead-acid batteries is 20%, a discovery with policy implications. Neglecting to consider cost reductions in lead-acid batteries could result in failure of energy storage start-ups and public policy programs. Generalizing this result, learning in incumbent technologies must be understood to assess the potential of emerging ones. 相似文献
2.
天桥水电站是黄河中游北干上的第一座高泥沙、低水头、大流量的径流式试验电站。它成功的施工与运营经验不仅对在黄河中游北干上开发梯级水电站,而且对中小型径流式水电站的施工都具有重要的借鉴作用。这篇文章总结了两期截流工程、基坑排水、固结灌浆、帷幕灌浆方面的施工经验。在诸如厂房位置的选择以及它的布置,泥沙、冰凌、洪水以及拦污方面的工程设计与运营的宝贵经验,使得水库长期保持高的有效库容和良好的运营状态。特剐是防止进水口淤积和水轮机的磨蚀方面的七条措施是非常有价值的。 相似文献
3.
《C语言程序设计》是计算机专业学习中的一门基础的课程.是培养学生对计算机学习兴趣的关键课程。提出C语言教学过程中存在的一些问题。对问题进行分析,提出解决问题的方法。根据笔者的多年的教学实践,阐述一些教学方法和教学经验,对教师在教学思路和方法上有一定的指导意义,能够更好地提高教学水平。 相似文献
4.
韩璐 《武汉纺织工学院学报》2014,(5):74-76
住区环境是人类生存最重要的一个空间,里分民居更是武汉历史发展过程中留下的宝贵历史遗产。通过引用用户体验的相关理论,对武汉里分民居的住区环境进行走访调查研究,并从使用者的心理需求出发,提出切实可行的解决方案,认为要实现里分民居住区环境与使用者需求的真正连接,做到里分民居环境的改善,需做到:整改当前混乱境况,保证居民的生理与安全需求;加强人与环境互动,拓展民居住区的交往与休闲空间;充分利用建筑的独特风格,提升民居的艺术与历史价值。 相似文献
5.
Safety critical control is often trained in a simulated environment to mitigate risk. Subsequent migration of the biased controller requires further adjustments. In this paper, an experience inference human-behavior learning is proposed to solve the migration problem of optimal controllers applied to real-world nonlinear systems. The approach is inspired in the complementary properties that exhibits the hippocampus, the neocortex, and the striatum learning systems located in the brain. The hippocampus defines a physics informed reference model of the real-world nonlinear system for experience inference and the neocortex is the adaptive dynamic programming (ADP) or reinforcement learning (RL) algorithm that ensures optimal performance of the reference model. This optimal performance is inferred to the real-world nonlinear system by means of an adaptive neocortex/striatum control policy that forces the nonlinear system to behave as the reference model. Stability and convergence of the proposed approach is analyzed using Lyapunov stability theory. Simulation studies are carried out to verify the approach. 相似文献
6.
目的研究基于体验式设计在博物馆馆藏资源跨界开发中的应用形式。方法通过对体验式设计概念的论述与剖析,以体验式设计应用中情感消费、体验互动以及多维度的开发方式等优势为基础,分析探究其在博物馆馆藏资源跨界开发中的表现形式。结论随着"活化"与"跨界"开发理念不断推广与应用,体验式设计越发成为馆藏资源与大众交流的一种沟通渠道,博物馆逐步摆脱了对馆藏资源以往静态的展示方式,借助以体验式为核心的多种跨界开发方式将博物馆馆藏资源更好的传播出去,顺应大众日益增长的文化消费需求。 相似文献
7.
In this study, we are concerned with system modeling which involves limited data and reconciles the developed model with some previously acquired domain knowledge being captured in the format of already constructed models. Each of these previously available models was formed on a basis of extensive data sets which are not available for the current identification pursuits. To emphasize the nature of modeling being guided by the reconciliation mechanisms, we refer to this mode of identification as experience-consistent modeling. The paper presents the conceptual and algorithmic framework by focusing on regression models. By forming a certain extended form of the performance index, it is shown that the domain knowledge captured by regression models can play a similar role as a regularization component used quite commonly in system identification. Experimental results involve both synthetic low-dimensional data and selected data coming from Machine Learning repository. The data used in the experiments tackle regression models as well as classification problems (two-class classifiers). 相似文献
8.
The purpose of the present study was to examine the prevalence of cyber-bullying through Facebook in a sample of 226 Greek university undergraduates, and to explore whether big five personality characteristics, narcissism, as well as attitudes toward Facebook, technological knowledge and skills were predictive of such behavior. Participants completed a self-report questionnaire measuring the above constructs. Results indicated that almost one third of the sample reported Facebook bullying engagement at least once during the past month, with male students reporting more frequent involvement than females. Bullying through Facebook was predicted by low Agreeableness and more time spent on Facebook only for males, whereas for females none of the studied variables predicted engagement in Facebook bullying. Findings are discussed in terms of prevention and intervention strategies. 相似文献
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