A contribution to estimate a benchmark capital stock. An optimal consistency method

There are alternative methods of estimating capital stock for a benchmark year. However, these methods are costly and time‐consuming, requiring the gathering of much basic information as well as the use of some convenient assumptions and guesses. In addition, a way is needed of checking whether the estimated benchmark is at the correct level. This paper proposes an optimal consistency method (OCM), which enables a capital stock to be estimated for a benchmark year, and which can also be used in checking the consistency of alternative estimates. This method, in contrast to most current approaches, pays due regards both to potential output and to the productivity of capital. It is applied to 45 cases for nine OECD countries and six Latin American ones. It works reasonably well, and it requires only small amounts of data, which are readily available. It appears to exhibit similar accuracy to alternative methods, but it is virtually inexpensive in both time and funding.     

The innovation impact of the EU Emission Trading System — Findings of company case studies in the German power sector

This paper provides a detailed analysis of how the European Emission Trading System (EU ETS) as the core climate policy instrument of the European Union has impacted innovation. Towards this end, we investigate the impact of the EU ETS on research, development and demonstration (RD&D), adoption, and organizational change. In doing so, we pay particular attention to the relative influences of context factors (policy mix, market factors and public acceptance) and firm characteristics (value chain position, technology portfolio, size and vision). Empirically, our qualitative analysis is based on multiple case studies with 19 power generators, technology providers and project developers in the German power sector which were conducted in 2008/09. We find that the innovation impact of the EU ETS has remained limited so far because of the scheme's initial lack of stringency and predictability and the relatively greater importance of context factors. Additionally, the impact varies significantly across technologies, firms, and innovation dimensions and is most pronounced for RD&D on carbon capture technologies and organizational changes. Our analysis suggests that the EU ETS on its own may not provide sufficient incentives for fundamental changes in corporate innovation activities at a level which ensures political long-term targets can be achieved.     

Emission trading in Europe with an exchange rate

This paper explores the analytical and empirical properties of a new method for emission trading according to a fixed exchange rate. The exchange rate is based on the ratios of the marginal costs of abatement in the optimal solution in order to account for the impact of the location of emission sources on the deposition. It is shown that, generally, this system will not achieve the optimal solution and does not guarantee that environmental deposition constraints are not violated, although total abatement costs are always reduced. A routine was developed to mimic trading as a bilateral, sequential process, subject to an exchange rate. In the example used, results for SO₂ emissions in Europe show that, starting from a uniform reduction, exchange-rate trading achieves higher cost savings than one-to-one trading, without achieving the cost minimum. Sulfur deposition targets are not violated since the initial emission allocation overfulfilled targets at many places. The results are sensitive to: pre-trade emission levels, the transaction costs, the availability of information on potential cost savings and assumptions made on the behavior of trading partners.     

What output-capital ratio to adopt for macroeconomic calibrations?

Regarding the output-capital ratio in heterodox macroeconomic simulation studies, a surprisingly wide range of numerical values can be found. The paper discusses quarterly US data that are publicly available where, in order to capture depreciation, the construction of the capital stock by the perpetual inventory method relies on detailed estimates of its lifetime. Subsequently the paper builds up a capital stock series by alternatively having recourse to the statistics about capital consumption and furthermore determining an initial level by an assumption about the long-term growth of capital. This procedure leads to somewhat different results. In addition, the rates of depreciation and profit are studied that are implied by the two approaches. The paper closes with two numerical proposals for the steady state values of these variables and the output-capital ratio that could be readily employed for macrodynamic modelling, and that are quite different from many of the aforementioned examples.     

中小型连锁超市物流系统优化研究

中小型连锁超市作为一种新型的商业零售业态,对我国经济发展起着重要作用,但其在采购管理、库存管理、配送系统等方面存在很多问题,严重制约了企业竞争力的进一步提高.本文建立了中小型连锁超市物流系统优化模型,以更好地对其物流系统进行优化.首先,在采购管理方面,应健全采购组织,科学管理供应商,并实施品类管理.其次,在库存管理方面,可通过自动建议补货,避免中小型连锁超市订购时的盲目性和经验主义;可采用重点分类法管理库存,让工作人员抓住库存管理中的主要矛盾;可通过实施供应商管理库存模式,充分发挥供应商的专业管理优势,实现双赢.其三,在配送系统方面,可利用作业成本法对配送系统进行成本分析,发现主要的作业成本动因,找出优化的关键点,并针对关键点进行持续优化改进.     

库存持有成本的降低途径简析

库存持有成本是与库存数量直接相关的那一部分成本。要准确地衡量物流系统的绩效,必须对持有成本进行精确分析。本文分析了物流系统中库存持有成本的构成及影响因素,并对库存持有成本的降低途径提出几点浅见。     

基于Web的物料库存管理系统的研究

在对我国离散制造业物料库存管理业务调研和需求分析的基础上，构建了基于Web的物料库存管理系统。首先分析物料库存管理的业务流程，然后进行物料库存管理系统功能模型的设计，运用面向对象思想给出系统信息模型，并据此遵循J2EE框架构建系统软件实现体系。     

供应链管理下基于供货不稳定的最优库存模型

针对供货环境的不稳定性,将t时刻系统所处的状态(是否能够供货)视为连续时间的马尔可夫链。在(s,S)存储策略下,利用两状态连续时间马尔可夫链的性质建立了一个新的存贮控制模型。在给定具体数值的基础上利用遗传算法对模型进行了检验计算,并对结果进行了对比分析。