Inventory Rationing in a Make‐to‐Stock System with Batch Production and Lost Sales

We address an inventory rationing problem in a lost sales make‐to‐stock (MTS) production system with batch ordering and multiple demand classes. Each production order contains a single batch of a fixed lot size and the processing time of each batch is random. Assuming that there is at most one order outstanding at any point in time, we first address the case with the general production time distribution. We show that the optimal order policy is characterized by a reorder point and the optimal rationing policy is characterized by time‐dependent rationing levels. We then approximate the production time distribution with a phase‐type distribution and show that the optimal policy can be characterized by a reorder point and state‐dependent rationing levels. Using the Erlang production time distribution, we generalize the model to a tandem MTS system in which there may be multiple outstanding orders. We introduce a state‐transformation approach to perform the structural analysis and show that both the reorder point and rationing levels are state dependent. We show the monotonicity of the optimal reorder point and rationing levels for the outstanding orders, and generate new theoretical and managerial insights from the research findings.     

Heuristics for cross-docking scheduling of truck arrivals,truck departures and shop-floor operations

Journal of Combinatorial Optimization - This work studies the problem of cross-docking truck scheduling introduced by (Int J Prod Econ 194:102–112, Serrano et al. 2017), where...     

多层次语用语境因素对英语习语意义的影响

在对语用语境因素作了层次划分的基础上,文章试图探讨不同层次的语用语境因素对英语习语本体意义、语用意义和语义特征产生的影响,旨在强调语用语境因素对英语习语意义的制约作用,以增强语言使用者、学习者和英语教师在不同情境中处理英语习语时的语境意识。     

“放管服”改革政策创新扩散的驱动因素研究——基于31个省级政府的实证研究

放管服改革是国家重塑政府与市场关系,深化行政体制改革、转变政府职能的重要内容。其改革的理论逻辑及实践探索已经受到学术界的关注,但鲜有学者对放管服改革的影响因素进行探索,论文采用事件史分析法对2015—2020年31个省级政府影响放管服改革政策创新扩散的内外部因素进行深入分析。研究发现:单因素回归模型中内部因素财政资源对放管服改革的创新扩散影响并不显著,但在综合模型中较为显著;人口规模、经济发展程度在单因素回归分析中大部通过了显著性检验,综合模型中则不显著为正,对政策的创新扩散假设得到了部分验证;外部影响因素中领导者学历因素、府际竞争、中央压力、认知压力都对政策的创新扩散产生了显著影响,其中府际竞争、中央压力因素是政策创新扩散的主要驱动因素,而府际学习中的领导者年龄因素对政策的创新扩散影响并不显著;市场化程度在单因素回归中通过了显著性检验,而综合模型中不显著为正,对影响放管服改革创新扩散的假设得到了部分验证。     

自贸试验区打造参与国际经济治理试验田研究

自贸试验区应按照构建开放型经济新体制和十四五规划的要求,加快对接高标准国际经贸规则,推动部分规则先行先试,加大压力测试,重点在贸易投资、金融开放等方面进行探索,促进政府部门加强统筹协调,形成政策合力,以提升自贸试验区发展的质量和效益.与此同时,还要强化改革开放力度,加强事中事后监管,发挥自贸试验区在国际经济治理试验田方面的作用,形成可复制可推广的经验,更好地服务新发展格局.     

Penalized pseudo-likelihood hazard estimation: A fast alternative to penalized likelihood

Penalized likelihood method has been developed previously for hazard function estimation using standard left-truncated, right-censored lifetime data with covariates, and the functional ANOVA structures built into the log hazard allows for versatile nonparametric modeling in the setting. The computation of the method can be time-consuming in the presence of continuous covariates; however, due to the repeated numerical integrations involved. Adapting a device developed by Jeon and Lin [An effective method for high dimensional log-density ANOVA estimation, with application to nonparametric graphical model building. Statist. Sinica 16, 353–374] for penalized likelihood density estimation, we explore an alternative approach to hazard estimation where the log likelihood is replaced by some computationally less demanding pseudo-likelihood. An assortment of issues are addressed concerning the practical implementations of the approach including the selection of smoothing parameters, and extensive simulations are presented to assess the inferential efficiency of the “pseudo” method as compared to the “real” one. Also noted is an asymptotic theory concerning the convergence rates of the estimates parallel to that for the original penalized likelihood estimation.     

当代中国发展需要哲学家的声音

改革开放30年来,中国经济蓬勃发展,社会日益进步,中国经济学家的作用功不可没,但与中国经济快速发展形成鲜明对比的是中国经济学界也出现了某种背离公众利益的趋向,为此,迫切需要哲学社会科学予以矫正,以利于中国经济的持续健康发展和中国理论经济学的真正繁荣。     

地方政府强制拆迁的成本收益分析

我国地方政府在城市化进程中扮演着重要的角色。伴随城市化进程而来的是地方政府主导的强制拆迁行为。地方政府进行强制拆迁面临着有形成本、交易成本、风险成本和公信力成本;但与此同时,地方政府通过强制拆迁又可以获得"第二财政"收益、政绩收益、制度租金收益、灰色租金收益和威慑收益。地方政府之所以采取强制这样"非常规"的拆迁方式,是基于收益最大化或者至少预期拆迁收益大于预期拆迁成本的考虑,地方政府实施强制拆迁行为的动力源在于将收益为正并使之最大化。     

社会保障的思想渊源

纵观人类历史,社会保障的制度化发展并形成一门学科有其深厚的思想渊源:包括人类古老、传统的道德观及其发展延续;人类出于社会管理的需要;各民族特有的指向社会保障的思想--以中国为例:内容丰富且体系化.深厚的思想渊源促进了作为人类文明标志之一的社会保障的发展.     

政治与学术的良性互动:马克思主义中国化新进展

1978年改革开放以来我们取得一切成绩和进步的根本原因,归结起来就是,把马克思主义进一步中国化,形成了中国特色社会主义理论体系,开辟了中国特色社会主义道路.马克思主义中国化可分为政治层面的中国化和学术层面的中国化两个方面.政治层面的马克思主义中国化与学术层面的马克思主义中国化相辅相成、相映成辉,共同开辟了中国特色社会主义新道路.