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71.
针对零售商主导的考虑政府补贴和规模效应的动力电池闭环供应链,研究成员最优决策及协调问题。分别在无补贴、补贴零售商、补贴制造商、补贴第三方回收商四种情形下,分析了补贴对象、规模效应、再制造动力电池比例对成员最优决策及利润的影响,并实现了闭环供应链的协调。研究表明:政府补贴能够降低零售价,提高回收率以及各成员利润;补贴第三方回收商相比补贴零售商和补贴制造商而言,回收率以及第三方回收商利润提高更为明显,补贴零售商和补贴制造商相比补贴第三方回收商而言,零售价降低、制造商和零售商利润提高更为明显;可用于再制造的废旧动力电池比例增大能够降低动力电池销售价格,提高动力电池回收率;第三方回收商规模效应的增大有利于降低零售价格,提高动力电池产品回收率及闭环供应链各成员收益。 相似文献
72.
针对产出存在不确定性的特征,利用Stackelberg博弈模型研究基于政府补贴的绿色供应链激励机制,通过数理方法分析随机产出因素对供应链成员决策与利润的影响,并借助数值算例分析政府补贴对绿色供应链的激励效果。研究结果表明:随着随机产出率水平的提高,制造商、零售商与消费者均能够受益,而随着随机产出波动水平的增大,制造商与零售商均有所损失,产品的绿色度水平和产品的平均销售价格均降低;政府补贴政策能够降低随机产出波动因素所带来的供应链成员收益下降与绿色产品销售价格升高的风险。 相似文献
73.
E.L. Comrie C. Burns A.B. Coulson J. Quigley K.F. Quigley 《European Journal of Operational Research》2019,272(2):792-801
Communication of health risk events is a complex and challenging task. The advent of information and communication technology along with the following popularisation and widespread uptake of social media are reshaping the field of risk communication. Guided by key tenets of the Social Amplification of Risk Framework, this study developed a causal loop diagram, capturing the perceptions of professionals in health organisations regarding the role of Twitter during risk events. The aim of this paper is to explore the use of the causal loop diagram and its role with rationalising the use of Twitter in risk communication strategies. A key finding of the model is the central role of trust and its interrelationship with other factors during a risk event. A contribution is made to operational research through the novel use of soft system dynamics in risk communication, to risk communication through the investigation of the new medium Twitter and also to research on the Social Amplification of Risk Framework by providing a means through which to operationalise the framework. 相似文献
74.
Peter Junghans Solvig Görs Martina Langhammer 《Isotopes in environmental and health studies》2013,49(6):561-572
ABSTRACTWe explored a novel doubly labelled water (DLW) method based on breath water (BW-DLW) in mice to determine whole body CO2 production and energy expenditure noninvasively. The BW-DLW method was compared to the DLW based on blood plasma. Mice (n?=?11, 43.5?±?4.6?g body mass (BM)) were administered orally a single bolus of doubly labelled water (1.2?g H218O kg BM?1 and 0.4?g 2H2O kg BM?1, 99 atom% (AP) 18O or 2H). To sample breath water, the mice were placed into a respiration vessel. The exhaled water vapour was condensed in a cold-trap. The isotope enrichments of breath water were compared with plasma samples. The 2H/1H and 18O/16O isotope ratios were measured by means of isotope ratio mass spectrometry. The CO2 production (RCO2) was calculated from the 2H and 18O enrichments in breath water and plasma over 5 days. The isotope enrichments of breath water vs. plasma were correlated (R2?=?0.89 for 2H and 0.95 for 18O) linearly. The RCO2 determined based on breath water and plasma was not different (113.2?±?12.7 vs. 111.4?±?11.0?mmol?d–1), respectively. In conclusion, the novel BW-DLW method is appropriate to obtain reliable estimates of RCO2 avoiding blood sampling. 相似文献
75.
Peter Junghans Caroline Larsson Rasmus Bovbjerg Jensen Anne-Helene Tauson 《Isotopes in environmental and health studies》2013,49(4):497-507
We reconsider the principle of the 13C bicarbonate (NaH13CO3) method (13C-BM) for the determination of the CO2 production to obtain an estimate of energy expenditure (EE). Its mathematical concept based on a three-compartmental model is related to the [15N]glycine end product method. The CO2 production calculated by the 13C-BM, RaCO2(13C) is compared to the result from the indirect calorimetry, RCO2(IC). In an interspecies comparison (dog, goat, horse, cattle, children, adult human; body mass ranging from 15 to 350?kg, resting and fasting conditions) we found an excellent correlation between the results of 13C-BM and IC with RCO2(IC)?=?0.703?×?RaCO2(13C), (R2?=?0.99). The slope of this correlation corresponds to the fractional 13C recovery (RF(13C)) of 13C in breath CO2 after administration of NaH13CO3. Significant increase in RF(13C) was found in physically active dogs (0.95?±?0.14; n?=?5) vs. resting dogs (0.71?±?0.10, n?=?17; p?=?.015). The 13C recovery in young bulls was greater in blood CO2 (0.81?±?0.05) vs. breath CO2 (0.73?±?0.05, n?=?12, p?<?.001) and in ponies with oral (0.76?±?0.03, n?=?8) vs. intravenous administration of NaH13CO3 (0.69?±?0.07; n?=?8; p?=?.026). We suggest considering the 13C-BM as a ‘stand-alone’ method to provide information on the total CO2 production as an index of EE. 相似文献
76.
In both public administration and economics, efficiency is brought forward as an important criterion for evaluating administrative actions. Clearly, its value as an assessment principle depends on our ability to adequately measure efficiency. This article argues that citizen’s coproduction in public services requires a careful reassessment of how we approach the measurement of productive efficiency in public service delivery. Theoretically, we illustrate that using observable outcomes (e.g., library circulation, school results, health outcomes, fires extinguished, and crimes solved) as output indicators is inappropriate and leads to biased estimates of public service providers’ productive efficiency. This bias arises because citizens co-determine final outputs, leaving them at least partly beyond the service providers’ control. Empirically, we find supportive evidence of both the existence and importance of such ‘demand-induced’ bias. 相似文献
77.
通过将公共投资指数与社会生产总量联系起来,引入含消费与公共支出效用指数的双变量效用函数,提出社会效用最大化问题.求解优化问题得到描述模型的二维动力系统,首先证明了系统存在唯一的均衡点,并利用相图分析了模型存在唯一的最优路径. 相似文献
78.
针对现有社会保障支出与消费水平关系实证研究中存在的不足,应用时间序列的非线性STR模型验证了1952-2009年期间我国财政社保支出与消费水平非线性关系的存在.研究结论表明二者问呈显著的负相关关系,且呈现出明显的阶段性特征,并在线性和非线性间频繁转换.具体可分为三个主要阶段,1958-1963年为负向非线性关系,1964 1978年二者关系则很不显著;1979年至今又重新转变为负向非线性关系.这些结论为我国制定和实施社会保障支出政策提供了现实的理论依据. 相似文献
79.
80.
针对政府预算体系,由于部门采取的行为策略是基于有限理性而做出的,所以博弈双方的策略选择实际上是不断调整的,并且是根据对方策略的变化而不断变化的。因此,运用演化博弈工具来研究政政府预算体系更符合现实情况。基于此,从演化博弈理论的研究视角探讨了预算审批部门、预算申报部门和财政支出部门决策的演化过程,建立了预算审批部门和预算申报部门以及财政支出部门之间的演化博弈模型。分析了审批部门、申报部门和支出部门的行为特征,根据复制者动态方程得到了参与者的行为演化规律和行为演化稳定策略。最后,文章通过数值算例对结论进行了论证。 相似文献