电动汽车充换电站(battery charging and swapping station,BCSS)是中国电动汽车应用的重要基础设施之一,得到了广泛关注和示范推广。BCSS的成本收益模型对BCSS商业化推广是至关重要的,文中探讨了电动汽车BCSS的组成结构和运营模式,选...电动汽车充换电站(battery charging and swapping station,BCSS)是中国电动汽车应用的重要基础设施之一,得到了广泛关注和示范推广。BCSS的成本收益模型对BCSS商业化推广是至关重要的,文中探讨了电动汽车BCSS的组成结构和运营模式,选择以电池租赁运营模式的BCSS为研究对象,考虑了其投资成本、运营和维护费用、人工薪酬等成本及充换电服务等收益,建立了基于净现值动态评价指标的电动汽车BCSS成本效益模型。最后以中国某大型电动汽车充换示范电站为实例,分析了该电站在全寿命周期内的成本收益模型,并进行了敏感性分析,得出了影响BCSS收益的关键因素依次为充换电服务价格、电池租赁费用、购电价格等。该模型及分析结果为电动汽车BCSS商业化运行提供了成本收益评估和决策依据。展开更多
关于最优国际储备理论与测度的探讨,"二战"后经历了"比率分析模型"、"成本效益分析模型"、"缓冲存货模型"、"Ben-Bassat and Gottlieb最优化模型"、"基于效用最大化的模型"...关于最优国际储备理论与测度的探讨,"二战"后经历了"比率分析模型"、"成本效益分析模型"、"缓冲存货模型"、"Ben-Bassat and Gottlieb最优化模型"、"基于效用最大化的模型"等阶段。深入剖析其发展脉络,可以明确,一国持有国际储备的最主要目的,是应对一国宏观经济所可能受到的异常冲击,因而一国不但应持有正常的国际储备,还应保有能应对超出这一正常需要的额外储备;而一国持有国际储备总量的最优水平,则应综合考虑持有这些国际储备的福利和为此所需付出的机会成本。中国国际储备问题的研究,应考虑到国际储备的各种枯竭可能性,改善对宏观经济危机或动荡的发生概率的估计,并加强对宏观经济危机后果的测定。因此,若能发展出适合于我国国情,既具理论根据又简单易懂易操作,并且能考虑到内源和外源经济冲击的比率,如适当的国际储备对GDP的比率、国际储备对进口的比率和国际储备对货币供应量的比率,将是合意的。展开更多
The rapid development of multimodal transportation system prompts travellers to choose multiple transportation modes, such as private vehicles or taxi, transit(subways or buses), or park-and-ride combinations for urba...The rapid development of multimodal transportation system prompts travellers to choose multiple transportation modes, such as private vehicles or taxi, transit(subways or buses), or park-and-ride combinations for urban trips. Traffic corridor is a major scenario that supports travellers to commute from suburban residential areas to central working areas. Studying their modal choice behaviour is receiving more and more interests. On one hand, it will guide the travellers to rationally choose their most economic and beneficial mode for urban trips. On the other hand, it will help traffic operators to make more appropriate policies to enhance the share of public transit in order to alleviate the traffic congestion and produce more economic and social benefits. To analyze the travel modal choice, a generalized cost model for three typical modes is first established to evaluate each different travel alternative. Then, random utility theory(RUT) and decision field theory(DFT) are introduced to describe the decision-making process how travellers make their mode choices. Further, some important factors that may influence the modal choice behaviour are discussed as well. To test the feasibility of the proposed model, a field test in Beijing was conducted to collect the real-time data and estimate the model parameters. The improvements in the test results and analysis show new advances in the development of travel mode choice on multimodal transportation networks.展开更多
The combustion process of pulverized coal injected into blast furnace involves a lot of physical and chemical reactions. Based on the combustion behaviors of pulverized coal, the conception of coal effective calorific...The combustion process of pulverized coal injected into blast furnace involves a lot of physical and chemical reactions. Based on the combustion behaviors of pulverized coal, the conception of coal effective calorific value representing the actual thermal energy provided for blast furnace was proposed. A cost performance evaluation model of coal injection was built up for the optimal selection of various kinds of coal based on effective calorific value. The model contains two indicators: coal effective calorific value which has eight sub-indicators and coal injection cost which includes four sub-indicators. In addition, the calculation principle and application of cost performance evaluation model in a Chinese large-scale iron and steel company were comprehensively introduced. The evaluation results finally confirm that this novel model is of great significance to the optimal selection of blast furnace pulverized coal.展开更多
文摘电动汽车充换电站(battery charging and swapping station,BCSS)是中国电动汽车应用的重要基础设施之一,得到了广泛关注和示范推广。BCSS的成本收益模型对BCSS商业化推广是至关重要的,文中探讨了电动汽车BCSS的组成结构和运营模式,选择以电池租赁运营模式的BCSS为研究对象,考虑了其投资成本、运营和维护费用、人工薪酬等成本及充换电服务等收益,建立了基于净现值动态评价指标的电动汽车BCSS成本效益模型。最后以中国某大型电动汽车充换示范电站为实例,分析了该电站在全寿命周期内的成本收益模型,并进行了敏感性分析,得出了影响BCSS收益的关键因素依次为充换电服务价格、电池租赁费用、购电价格等。该模型及分析结果为电动汽车BCSS商业化运行提供了成本收益评估和决策依据。
文摘储能辅助常规机组参与电网调频,可以改善常规机组调频的弊端,提高调频质量,有利于提高系统的稳定性。通过变分模态分解(Variational Mode Decomposition, VMD)将调频指令信号进行初级分配,在考虑机组的爬坡限制以及储能的功率和荷电状态(State Of Charge, SOC)等限制后,确定各调频源在每分钟内的功率约束。提出了指令信号越限时再分配的方法,以实现在每分钟时间段内以最优比例在两种资源间分配调频指令。以所构建的成本-效益模型为目标,通过粒子群算法进行寻优,从而得到经济性最优的储能容量配置。最后基于实测的区域控制误差(Area Control Error, ACE)信号,分析了不同分配方案对储能容量配置、效益以及技术性的影响,验证了所提方法的可行性与有效性。
文摘关于最优国际储备理论与测度的探讨,"二战"后经历了"比率分析模型"、"成本效益分析模型"、"缓冲存货模型"、"Ben-Bassat and Gottlieb最优化模型"、"基于效用最大化的模型"等阶段。深入剖析其发展脉络,可以明确,一国持有国际储备的最主要目的,是应对一国宏观经济所可能受到的异常冲击,因而一国不但应持有正常的国际储备,还应保有能应对超出这一正常需要的额外储备;而一国持有国际储备总量的最优水平,则应综合考虑持有这些国际储备的福利和为此所需付出的机会成本。中国国际储备问题的研究,应考虑到国际储备的各种枯竭可能性,改善对宏观经济危机或动荡的发生概率的估计,并加强对宏观经济危机后果的测定。因此,若能发展出适合于我国国情,既具理论根据又简单易懂易操作,并且能考虑到内源和外源经济冲击的比率,如适当的国际储备对GDP的比率、国际储备对进口的比率和国际储备对货币供应量的比率,将是合意的。
基金Project(2012CB725405)supported in part by National Basic Research Program of ChinaProject(2014BAG03B01)supported by the National Science and Technology Support Program,China+1 种基金Project(71301083)supported by the National Natural Science Foundation of ChinaProject(20131089307)supported by the Project Supported by Tsinghua University,China
文摘The rapid development of multimodal transportation system prompts travellers to choose multiple transportation modes, such as private vehicles or taxi, transit(subways or buses), or park-and-ride combinations for urban trips. Traffic corridor is a major scenario that supports travellers to commute from suburban residential areas to central working areas. Studying their modal choice behaviour is receiving more and more interests. On one hand, it will guide the travellers to rationally choose their most economic and beneficial mode for urban trips. On the other hand, it will help traffic operators to make more appropriate policies to enhance the share of public transit in order to alleviate the traffic congestion and produce more economic and social benefits. To analyze the travel modal choice, a generalized cost model for three typical modes is first established to evaluate each different travel alternative. Then, random utility theory(RUT) and decision field theory(DFT) are introduced to describe the decision-making process how travellers make their mode choices. Further, some important factors that may influence the modal choice behaviour are discussed as well. To test the feasibility of the proposed model, a field test in Beijing was conducted to collect the real-time data and estimate the model parameters. The improvements in the test results and analysis show new advances in the development of travel mode choice on multimodal transportation networks.
基金Project(51134008)supported by the National Natural Science Foundation of ChinaProject(2012CB720401)supported by the National Basic Research Program of China
文摘The combustion process of pulverized coal injected into blast furnace involves a lot of physical and chemical reactions. Based on the combustion behaviors of pulverized coal, the conception of coal effective calorific value representing the actual thermal energy provided for blast furnace was proposed. A cost performance evaluation model of coal injection was built up for the optimal selection of various kinds of coal based on effective calorific value. The model contains two indicators: coal effective calorific value which has eight sub-indicators and coal injection cost which includes four sub-indicators. In addition, the calculation principle and application of cost performance evaluation model in a Chinese large-scale iron and steel company were comprehensively introduced. The evaluation results finally confirm that this novel model is of great significance to the optimal selection of blast furnace pulverized coal.
