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91.
在实际中,消费者购买耐用品时均同时获得厂商提供的质保服务,由于产品质保服务影响着消费者的产品使用效用,因此耐用品定价、质保期和产品质保服务投入是影响厂商利润的主要因素。考虑双寡头市场环境下,建立微分博弈模型讨论单位产品质保服务投入和产品质保期对双寡头厂商均衡价格的影响。结论表明双寡头厂商的单位产品质保服务投入越高、质保期越长,均衡价格越高;但单位产品保服务投入与质保服务对消费者效用影响系数的关系影响着竞争对手在均衡价格的变化趋势;劣势的低质量厂商可以通过增加单位产品质保服务投入策略或延长质保期的策略实现在均衡下与高质量厂商以同等价格销售耐用品,但劣势厂商增加单位产品质保服务投入策略要优于延长质保期策略。最后,利用数值分析进一步验证了所得结论的有效性。  相似文献   
92.
通常模拟混相驱动态采用组分模型,由于组分模型求解工作量大,计算速度慢,要求输入的参数较多,而这些参数很难取全取准,同时组分模型不易被油藏工程师所掌握。因此,介绍了一种模拟混相驱动态的模拟模型,该模型是在黑油模型基础上发展起来的拟四组分模型,它兼有黑油模型和多组分模型的某些优点,如黑油模型的稳定性好和计算速度快、组分模型的可模拟凝析气藏和混相驱等;给出了数学模型及各种物理参数以及混相流体性质的处理方法。该模型还以SPE为例进行计算,结果与SPE的结果一致,从而验证了本模型的可靠性。  相似文献   
93.
2018年3月,日本发布新的《高等学校学习指导要领》。这是日本自第二次世界大战后70多年来,对高中课程最大规模的一次修订,体现了日本高中教育发展的新趋势,标志着日本从此告别“宽松教育”而走向“生存能力”教育。由“历史综合”“日本史探究”“世界史探究”组成的新高中历史课程,立足“人”的发展,构建了“必修+选修、通史+专题”的课程体系,课程内容更加突出本国史与世界史的联系,课程学习倡导“主题+探究”的学习方式。日本高中历史课程的内容设置及特点启示我们,高中历史课程编制应加强中国史与世界史的横向关联,课程内容应体现探究性学习要求。  相似文献   
94.
Despite the wealth that comes from being the biggest oil producer in Africa, Nigeria has some of the worst development indicators in the world. From 2011 to mid‐2016, the DFID‐funded Facility for Oil Sector Transparency and Reform (FOSTER) programme's unique design aimed to reduce incentives for the capture of oil revenue by elites and international oil companies, restoring the potential of those revenues to accelerate economic and social development. This article asks what lessons FOSTER's successes and failures offer for improved “thinking and working politically” (TWP). It examines the outcomes from five “clusters” of interventions: three viewed by the FOSTER team as successes and two as failures. The article identifies factors for successful TWP‐based programming, including the need for local ownership rooted in staff with a combination of technical expertise, a deep knowledge of the local political context and excellent networking abilities. The research used a qualitative and inductive approach. Field research was undertaken with 44 semi‐structured qualitative interviews during one month of fieldwork in Abuja and Lagos. The research also included reviews of FOSTER's internal documentation and evaluation frameworks, as well as analysis of newspaper articles and grey literature on the oil sector in Nigeria. The project offers important lessons for politically informed programming about how interventions were implemented (process), what was actually done (content) and how the project responded to changes in context that created or blocked opportunities for reform (responsiveness). The article identifies factors for successful TWP‐based programming, including the need for local ownership rooted in staff with a combination of technical expertise, a deep knowledge of the local political context and excellent networking abilities. The findings have important implications for programme design. They demonstrate the value of built‐in flexibility that allows staff to choose and switch the partners they work with and the channels they work through. They also show that a key aspect of TWP‐based programming is implicit acceptance that some failure may be unavoidable, since this permits staff to balance risk against opportunities. Finally, a better understanding of FOSTER's failures reveals the challenges of a TWP‐based approach and the trade‐offs it demands.  相似文献   
95.
In this paper, we consider the problem of estimating the Laplace transform of volatility within a fixed time interval [0,T] using high‐frequency sampling, where we assume that the discretized observations of the latent process are contaminated by microstructure noise. We use the pre‐averaging approach to deal with the effect of microstructure noise. Under the high‐frequency scenario, we obtain a consistent estimator whose convergence rate is , which is known as the optimal convergence rate of the estimation of integrated volatility functionals under the presence of microstructure noise. The related central limit theorem is established. The simulation studies justify the finite‐sample performance of the proposed estimator.  相似文献   
96.
本文考虑一个供应商和两个独立零售商构成的供应链系统。当供应商的产能受到约束时,零售商可能会竞争有限的产能。本文提出将“优先分配权”作为一个有价值的标的物进行拍卖,按照出价高低确定优先分配顺序。本文证明了优先权拍卖机制属于共同价值模型,并提出了两类拍卖机制:事先拍卖和事后拍卖。本文证明两类优先权拍卖机制均会促使零售商提交真实的需求作为订单量,并且满足收益等价定理。而就供应商期望利润而言,事后优先权拍卖机制要高于事先优先权拍卖机制。  相似文献   
97.
In this article, Six Sigma zone control charts (SSZCCs) are proposed for world class organizations. The transition probabilities are obtained using the Markov chain approach. The Average Run Length (ARL) values are then presented. The ARL performance of the proposed SSZCCs and the standard Six Sigma control chart (SSCC) without zones or run rules is studied. The ARL performance of these charts is then compared with those of the other standard zone control charts (ZCCs), the modified ZCC and the traditional Shewhart control chart (SCC) with common run rules. As expected, it is shown that the proposed SSZCC outperforms the standard SSCC without zones or run rules for process shifts of any magnitude. When compared to the other standard ZCCs and the Shewhart chart with common run rules, it is observed that the proposed SSZCCs have much higher false alarm rates for smaller shifts and hence they prevent unwanted process disturbances. The application of the proposed SSZCC is illustrated using a real time example.  相似文献   
98.
In this paper, we provide a test of the sustainability of the Spanish government deficit over the period 1850–2000, emphasizing the role played by monetary and fiscal dominance in order to get fiscal solvency. Since the condition of fiscal solvency was satisfied, government deficit would have been sustainable along the sample period. In addition, the whole period can be characterized as one of fiscal dominance.  相似文献   
99.
20世纪70年代的国际石油危机有着深厚的历史根源,它源于国际石油权力结构的急剧变革。60年代后期开始,随着国际石油市场日趋紧张,产油国的地位日益改善,它们从石油公司获得越来越多的石油权力,其中国际石油公司与产油国签订的"德黑兰协定"和"的黎波里协定"发挥了至关重要的作用,是产油国能够针对西方国家使用减产、禁运和提价等石油武器的前提条件。  相似文献   
100.
思想政治理论课是大学生思想政治教育的主渠道,而课堂教学在主渠道的畅通中承担着主要的任务。针对课堂教学存在的诸多问题,教学改革尤为迫切。深入调查研究,及时掌握和分析大学生的各种信息是教学改革最为基础性的工作;树立以生为本理念,课堂教学追求多样性实效性是教学改革的外在表现;教书育人,当好大学生健康成长的指导者和引路人则是思想政治理论课教师的根本职责和庄严使命。  相似文献   
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