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91.
微电网是智能电网的重要组成部分,可以有效协调区域内的电力资源。为研究面向储能的光伏微网电力成本变化情况和优化对策,基于微网多主体结构构建微网电力成本均衡模型,以微网内分布式光伏供应及用户电力需求的统计数据为主要输入对象,并设置变量来区分不同情景下的分布式可再生能源发电量,建立以时间为自变量的微网分布式电力收益函数和用户购电成本函数,刻画微网电力资源调度的动态均衡变化。基于微网电力资源调度实例,发现微网在并网情景下的购电成本小于储能情景下的购电成本(C并=2 033.6元C储=2 633.6元),且储能情景下购电成本的22.8%都来自储能设施的日折旧费,因此,加大科技研发和增强微网协同管理可以降低微网成本。 相似文献
92.
The Colorectal Cancer Control Program (CRCCP) provided funding to 29 grantees to increase colorectal cancer screening. We describe the screening promotion costs of CRCCP grantees to evaluate the extent to which the program model resulted in the use of funding to support interventions recommended by the Guide to Community Preventive Services (Community Guide). We analyzed expenditures for screening promotion for the first three years of the CRCCP to assess cost per promotion strategy, and estimated the cost per person screened at the state level based on various projected increases in screening rates. All grantees engaged in small media activities and more than 90% used either client reminders, provider assessment and feedback, or patient navigation. Based on all expenditures, projected cost per eligible person screened for a 1%, 5%, and 10% increase in state-level screening proportions are $172, $34, and $17, respectively. CRCCP grantees expended the majority of their funding on Community Guide recommended screening promotion strategies but about a third was spent on other interventions. Based on this finding, future CRC programs should be provided with targeted education and information on evidence-based strategies, rather than broad based recommendations, to ensure that program funds are expended mainly on evidence-based interventions. 相似文献
93.
张会永 《河南工业大学学报(社会科学版)》2012,8(4):63-70
贪污贿赂犯罪人员利用职权谋取私利具有经济学理性特征,因此,其行为必然遵从经济学的基本法则。用经济分析的方法研究了贪污贿赂犯罪的产生机理,探讨了贪污贿赂犯罪的预防措施。基于犯罪经济成本收益理论,通过实证分析,认为应增大犯罪成本,控制犯罪收益,以有效预防和减少贪污贿赂犯罪。 相似文献
94.
Joseph Costanzo 《Identities: Global Studies in Culture and Power》2014,21(1):42-59
Though sharing a common territory, the cultural spaces of Brussels are divided according to a complex structure where Francophone and Flemish Communities play a dominant role. These two language-based communities set separate cultural policies and programming for their residents in Brussels. Within this fragmented structure, local socio-cultural actors have mobilised promoting cross-Community collaboration towards a shared vision for the Brussels-Capital Region (ex. Cultural Plan for Brussels). Further, individual artists themselves have developed strategies to participate in Community-defined cultural programming and to gain recognition for their talent as local (Bruxellois) artists regardless of their ethnic, linguistic or migrant background. This article explores how socio-cultural actors and artists have mobilised to reframe ‘culture’ in Brussels, and to gain access to cultural venues particularly in the case of migrant and migrant-origin artists whose engagement and recognition in Brussels’ cultural scenes have been little studied. 相似文献
95.
李永洪 《西华师范大学学报(自然科学版)》2012,(5):1-7
我国农村基层民主近年来在广度和深度上都得到了较大发展。但是,在这种发展的表象背后,却隐藏着农民政治冷漠的客观真象。对此,既有的"复合因果论"具有一定解释力,但也有值得补遗之处。农村基层民主制度运行成本与运行绩效的不对称、农民个体承担的基层民主制度运行成本过高才是导致当前农民政治冷漠的根本原因。 相似文献
96.
I examine the role of Occupy Wall Street in shifting presidential and congressional discourse on economic fairness and inequality. Using data from 4646 presidential speeches and 1256 congressional records from 2009 to 2015, I test different mechanisms, including repression, media coverage, public opinion, and presidential agenda-setting by applying a novel combination of web scraping, natural language processing, and time series models. I suggest that movement success can be measured in its ability to shape discursive opportunity structures, and I argue that the role of the president should be at the forefront of social movements research. Ultimately, I demonstrate (1) that the repression of Occupy protesters not only predicts media coverage but also increases discursive opportunities through President Obama and Congress, (2) that media coverage of Occupy predicts presidential discourse, (3) that the president's rhetorical shift increases congressional response, and (4) that this change persists after the movement faltered. 相似文献
97.
梁仲靖 《甘肃联合大学学报(社会科学版)》2012,28(6):114-121
援西军的组建和出动是"西安事变"之后中共中央为挽救西路军免遭失败而实施的一次重大军事援救行动。本文通过对援西军行动的背景、必要性和紧迫性进行分析,重点阐述了援西军出动面临的各类困难和不利因素,并就西路军救援时机问题进行了探讨。 相似文献
98.
联运企业的效益受运输路径和运输方式的影响。如何降低联运成本、提高联运企业的效益,已成为学术研究的重中之重。针对集装箱公铁联运路径优化问题,以运输成本、换装成本、储存成本、时间惩罚成本构成的运输总成本为目标函数,建立集装箱公铁联运路径优化模型,考虑运输时间限制、班期限制、节点储存成本,得出使运输总成本最低的运输路径及运输方式,并利用算例验证模型的有效性。 相似文献
99.
通过梳理资本核算理论框架,结合中国实际情况测量了1981-2014年资本服务流量。资本分类、组合役龄效率-退役剖面计算、资本回报率确定和初始单位效率生产性资本存量估计等方面与既有研究有所不同。测量结果表明:按照1990年不变价格,各类资本服务流量呈增加趋势,其中无形资产服务流量前期较为波动;设备类服务流量增速最高;总资本服务增长率前期呈V型后期呈倒U型,与GDP增速变动不一致,整体来看前者高于后者;比较发现测量结果高于其它研究,差距先收敛后扩大。 相似文献
100.
《Omega》2017
In general cases, to find the exact upper bound on the minimal total cost of the transportation problem with varying demands and supplies is an NP-hard problem. In literature, there are only two approaches with several shortcomings to solve the problem. In this paper, the problem is formulated as a bi-level programming model, and proven to be solvable in a polynomial time if the sum of the lower bounds for all the supplies is no less than the sum of the upper bounds for all the demands; and a heuristic algorithm named TPVDS-A based on genetic algorithm is developed as an efficient and robust solution method of the model. Computational experiments on benchmark and new randomly generated instances show that the TPVDS-A algorithm outperforms the two existing approaches. 相似文献