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121.
We consider the compound Markov binomial risk model. The company controls the amount of dividends paid to the shareholders as well as the capital injections in order to maximize the cumulative expected discounted dividends minus the discounted capital injections and the discounted penalties for deficits prior to ruin. We show that the optimal value function is the unique solution of an HJB equation, and the optimal control strategy is a two-barriers strategy given the current state of the Markov chain. We obtain some properties of the optimal strategy and the optimal condition for ruining the company. We offer a high-efficiency algorithm for obtaining the optimal strategy and the optimal value function. In addition, we also discuss the optimal control problem under a restriction of bounded dividend rates. Numerical results are provided to illustrate the algorithm and the impact of the penalties. 相似文献
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AbstractThe promise of digitalization is enormous and nowhere is it more critical than in its potential to transform food supply chain. Consumers have become more educated and are demanding real-time updated information on foods they consumed through digital media. They are also increasingly demanding to know if the foods they consume are environmentally and socially sustainable or not. As a result, food product traceability, safety, and sustainability issues have become crucial concerns to food retailers, distributors, processors, and farmers. Digitalization allows food supply chains to be highly connected, efficient, and responsive to customer needs and regulation requirements. However, digitalizing a traditional food supply chain is challenging and resource demanding. This is more so for developing countries where moving food from farms to consumers can take months as it travels through an array of middlemen. Unfortunately, little is available in the existing literature on food supply chain digitalization. So far, current researchers mainly explore the benefits of digitalization. Using cases in three companies, this paper explores the practices, challenges, and opportunities faced by Thailand food manufacturers in digitalizing their food supply chains. A framework for food supply chain digitalization is proposed and its implications for research and practices are discussed. 相似文献
125.
This study experimentally examines the effect of electoral delegation on providing global public goods shared by several groups. Each group elects one delegate who can freely decide on each group member's contribution to the global public goods. Our results show that people mostly vote for delegates who assign equal contributions for every group member. However, in contrast to standard theoretical predictions for our delegation mechanism, unequal contributions across groups drive cooperation down over time, and it decreases efficiency by almost 50% compared to the selfish benchmark. This pattern is not driven by delegates trying to exploit their fellow group members, as indicated by theory. It is driven by conditional cooperation of delegates across groups. Since one of the potential sources of the resulting inefficiency is the polycentric nature of global public goods provision together with other‐regarding preferences, we use the term P‐inefficiency to describe our finding. (JEL C92, D72, H41) 相似文献
126.
〗“两个确立”为中国式现代化提供了根本保证。以中国式现代化推动中华民族伟大复兴,必须坚持中国共产党的全面领导,全面贯彻落实习近平新时代中国特色社会主义思想。“两个确立”坚定了中国式现代化的历史自信。新时代十年的伟大变革和历史性成就,充分证明中国式现代化顺应了社会历史发展的客观规律,是历史和人民的正确选择。“两个确立”增强了中国式现代化的文化自信,坚持了马克思主义现代化理论,弘扬了中华优秀传统文化,借鉴和吸收了人类文明优秀成果,开创了人类文明新形态。 相似文献
127.
标记是指某种事物的代号,是通过一一对应的方式用简洁的形式表现复杂的事物。为探讨不同标记对3-5岁幼儿数学语言理解的影响,选取某幼儿园160名3-5岁幼儿,随机分为空间标记组、序数标记组和颜色标记组,使用操作任务和《学前儿童数学语言评估》量表,测查幼儿对于数学语言的理解状况。结果表明:3-5岁幼儿在操作任务中的表现存在显著的年龄差异和组间差异;序数标记组和空间标记组的幼儿在操作任务中的得分与数学语言评估量表中的得分呈中等程度相关,且这两组幼儿在操作任务中的正确率高于数学语言评估量表中与序数、空间相关题目的正确率。在教育实践中,教师应将数学语言贯穿于幼儿数学学习的全过程、为幼儿提供适宜且有层级的支架物、重视幼儿在数学学习中的操作与表达。 相似文献
128.
黔东南苗族侗族自治州乡镇命名规律初探 总被引:1,自引:0,他引:1
谭厚锋 《贵州民族学院学报》2005,(4):24-27
由于各种原因使黔东南州地区古今地名参差杂乱。本文采用聚类分析法与传统的定性分析方法相结合,并联系黔东南州实情,就全州乡镇命名规律作一浅析。 相似文献
129.
W. Y. Tan 《Revue canadienne de statistique》1977,5(2):241-250
This paper provides necessary and sufficient conditions for a quadratic form in singular normal random variables to be distributed as a given linear combination of independent noncentral chi-square variables. Using this result, an extension of Cochran's theorem to quadratic forms of noncentral chi-square variables is derived. 相似文献
130.
从晚明墓碑文献中挖掘出大量的女性生活史料,藉此可以考察晚明知识女性的发展生态以及性别文化在晚明的异动信息:一、晚明墓碑文显示了经由文人家庭家族而实现的女性教育及其复杂生态,知识男性因父女、夫妻甚至公媳关系而实行着家庭生活中的女性教育,由此出现的知识女性随之改变了女性在家庭生活中的存在意义,进而促进了性别文化在晚明的观念异动;二、晚明墓碑文规模化呈现了晚明知识女性才学识多元发展的人文景观,知识女性在才学识多个层面展现了自己的风采;三、晚明墓碑文也客观描述了女性教育的妇德旨归,即令是在男性世界崇尚博学的文化思潮中,知识女性也只是才艺易受追捧而学识不受重视,显示了男性话语的固有立场,知识女性仍无出路。 相似文献