物流产业专业化对产业结构的空间溢出效应——基于技术进步的调节作用

在区域产业结构的调整过程中物流产业的作用日益突出, 物流产业依托技术进步的调节效应, 提高其专业化水平, 并且更能发挥其在产业结构转型升级的积极作用。 本文截取我国 2005～2015 年的空间面板数据, 借助Durbin 模型, 将技术进步作为调节因素, 考察物流产业专业化对区域产业结构的影响。研究结果表明： 我国区域物流产业专业化水平不均衡, 在其作用下全国以及东、 中、 西部地区产业结构演变具有显著的空间关联效应; 除了东部地区外, 物流产业专业化对本省和临近省份产业结构优化调整呈现鲜明的杠杆效应, 尤其是对产业结构高度化的促进作用较显著; 技术进步具备了明显的调节作用, 其对东、 中、西部地区产业结构高度化、 中、 西部地区产业结构合理化的正向辐射效应明显大于其本地效应。     

物流人才供求分析及对策研究——以上海“十二五”时期为例

为更好实现上海“十二五”规划目标,满足未来物流人才供求平衡,根据1970 ～ 2009年上海第三产业从业人员数据,借助基于灰色预测模型和时间序列预测分析的组合预测模型,预测“十二五”期间上海物流人才需求量;通过对上海开设物流相关专业的院校进行逐一考察,进一步得到上海物流人才有效供给量.发现上海物流人才在“十二五”期间出现供不应求现象,并从政府、高校、企业三方面提出缓解上海物流人才供求缺口的具体措施.     

武汉地区物流发展水平灰色预测

本文针对武汉物流中心发展规划中的具体问题，系统分析了影响武汉物流中心发展的各种因素，运用GM（1，1）灰色系统预测模型对武汉的物流规模进行了预测，定量计算结果与定性分析的结论一致。     

基于灰色马尔科夫修正的煤炭物流成本预测

为了探究物流成本之间的相互关系,引入灰色预测模型进行物流成本的预测,同时,引入马尔科夫链揭示物流总成本和预测值之间的相对误差在时间状态上的变化规律,预测未来某一时间节点上可能出现的状态,从而对预测值进行修正,提高预测准确性。最后,通过案例说明该方法的有效性。     

灰色系统模型在物流货物量预测中的应用

利用灰色系统理论建立物流货物量预测的GM(1，1)模型，并用模型对吉林省未来5—10年物流货物量作出预测。预测结果表明，灰色预测模型能很好模拟宏观物流系统的物流货物量。尽量发挥作为白信息的时问数据的作用，为探索宏观物流系统提供了很好的分析方法。     

港口物流与直接腹地经济耦合协调性研究——以天津、 营口等九海港型国家级物流枢纽为例

港口与腹地的协调在推动区域经济发展中起着关键作用。 为探讨较优的港口腹地协同发展机制, 本文以天津港、 营口港、 青岛港等九海港型国家级物流枢纽为研究样本, 基于 2009～2018 年统计数据, 通过构建耦合协调度模型进行耦合协调度测算及机理分析。 结果表明： 九港口协调度整体呈上升趋势; 同一时间截面下, 港口协调发展水平差距明显, 其发展模式可分为稳步增长型和间歇增长型; 港口协调度主要受港口物流运作模式、 腹地产业结构、 区域集疏运网络的影响。     

基于灰色模型和最小二乘机原理的区域水资源供需组合预测研究

文章将灰色模型和最小二乘机模型进行组合,并将组合模型用于辽宁西部区域水资源供需预测中。研究结果表明:组合模型可综合考虑不同模型的优点,进行加权组合预测,相比于单一预测模型,组合预测模型在区域水资源供需预测中具有较高的预测精度,预测误差得到明显改善。研究成果对于区域水资源供需预测方法提供参考。     

物流全球化及我国对外物流系统优化策略

本文对物流全球化这一概念进行了阐述，认为它是一种无国界观念，从事物流全球化的跨国企业需以全球的视点考虑消费者及其需求，从全球角度按照利益和效率标准进行物流决策。并分析了推动物流全球化的动力是现代信息革命、经济全球化、区域经济一体化、国际供应链一体化以及全球化经济的可持续发展要求。针对物流全球化背景下发展我国对外物流系统的有利和不利条件，提出了以联运企业的网络经营，改善物流系统的低组织化状态；建设高起点的物流基础设施，提升国内物流系统在国际物流系统中的地位；促进运输代理国际化，实现地区物流系统与国际物流系统的衔接；培育国际性的物流中心城市；与其他国家和地区政府加强合作等策略。     

基于灰色系统理论的中原地区物流预测模型探析

中原地区的区位优势,促进了该区域物流产业的快速发展.为使物流产业走上科学、可持续发展轨道,必须重视和有效发挥科学规划和准确预测的作用.本文借助灰色系统理论,通过对中原地区一些原始数据的分析,建立了一系列数学模型.并通过所建模型对该区域的物流规划给出了科学地预测,为早日完成这一朝阳产业向支柱产业的演进提出了建设性意见.     

区域物流发展影响因素的灰关联分析——以衢州市为例

区域物流在地区整体经济发展中的作用的凸显,使很多地区都备加注重区域物流的发展。本文运用灰关联法对影响衢州市区域物流发展的因素进行了深入分析,基于分析得出了衢州市区域物流的发展特征,并结合衢州市的地区特征,对促进衢州市区域物流发展提出了针对性的建议。     

Evaluating the robustness of lead time demand models

This paper examines the robustness of lead time demand models for the continuous review (r, Q) inventory policy. A number of classic distributions, (e.g. normal, lognormal, gamma, Poisson and negative binomial) as well as distribution selection rules are examined under a wide variety of demand conditions. First, the models are compared to each other by assuming a known demand process and evaluating the errors associated with using a different model. Then, the models are examined using a large sample of simulated demand conditions. Approximation results of inventory performance measures—ready rate, expected number of backorders and on-hand inventory levels are reported. Results indicate that distribution selection rules have great potential for modeling the lead time demand.     

A note on the excess entry theorem in spatial models with elastic demand

This paper revisits the excess entry theorem in spatial models according to Vickrey [Vickrey, W.S., 1964. Microstatics. Harcourt, Brace and World, New York] and Salop [Salop, S., 1979. Monopolistic competition with outside goods. Bell Journal of Economics 10, 141–156] while relaxing the assumption of inelastic demand. Using a demand function with a constant demand elasticity, we show that the number of firms that enter a market decreases with the degree of demand elasticity. We find that the excess entry theorem does only hold when the demand elasticity is sufficiently small. Otherwise, there is insufficient entry. In the limiting case of unit elastic demand, the market is monopolized. We broaden our results with a more general transportation cost function.     

中国药品市场的需求实证分析

以经济学理论中的弹性理论为前提,在采用计量经济学方法研究药品需求量与人均可支配收入、人们的健康水平、药品价格等因素间的相关性的基础上,应用excel软件构建药品需求的线性需求函数模型以及对数线性需求函数模型。最终得出结论:随着人们生活水平的提高,药品需求量将显著上升,而药品价格的变化对药品需求影响较小。     

Integrated safety stock optimization for multiple sourced stockpoints facing variable demand and lead time

The safety stock placement problem of a multi-stage supply chain comprising multiple sourced stockpoints is addressed in this paper. Each stockpoint faces variability in its downstream demand and suppliers' lead time. The maximum among these suppliers' lead time is determined by employing concepts of order statistics. It is required to find the fill rate and safety stocks at each stockpoint that leads to satisfying the end customer service level at minimum safety stock placement cost. Hence, the fill rates and the safety amounts are decided from a global supply chain perspective. Two models are proposed; a decentralized safety stock placement model and a centralized consolidation model. The decentralized model finds the safety amounts at each stockpoint required to face its underlying lead time demand variability. The consolidation model finds the consolidated safety amounts that will be kept in the relevant consolidation center at each stage. A Benders decomposition technique is developed to handle the nonlinearity and binary restrictions involved in the safety stock consolidation model. Strategies proposed by the consolidation model achieve 45.2-62% reduction in safety amounts that results in a cost savings ranging between 22.2-44.2% as compared to the strategies proposed by the decentralized model.     

Regional differences in residential demand for very high bandwidth broadband internet in 2025

The future demand for data and the role of gigabit networks are central issues in the context of Next Generation Access (NGA) network roll-out. Based on a generic model, which allows to predict unconstrained future broadband demand in different regions and countries, the authors compare the results for Germany, the UK and the Flemish region, and discuss reasons for the different outcomes. The generic market potential model thereby allows to project the future demand for bandwidth from residential customers on the basis of applications and their bandwidth needs, user profiles and population structure on a household level. Despite a general trend towards an increasing need for broadband, there are clear differences. On the one hand, these point to the relevance of socio-demographic factors for broadband adoption. On the other hand, the relatively high proportion of refusals shows that there is still a need for further educational work on the part of public authorities and providers. Finally, it has to be stated, that our forecast relies on the assumption that connectivity and thus that the availability of area-wide gigabit capable broadband access does not represent a bottleneck.     

集群环境下生产制造型企业与第三方物流的协同决策研究

为了解决集群环境下生产制造型企业与第三方物流之间合理的收益分配与风险共担问题,提高协同企业系统的运行效果,在探析集群环境下双方在协同模式中的收益与风险关系基础上,提出了基于Shapley值的协同收益分配与风险分摊决策模型,分别探索了以物流成本与收益分配,物流成本与风险损失两对变量之间的波动变化规律,并将之集成计算得出了协同选择的临界点与取值范围,辅助参与企业决策,通过实证研究验证了收益分配曲线与风险量化曲线的正向相关性波动规律。结果表明:集群环境中的生产制造型企业与第三方物流的协同模式具有以市场需求为中心的组织特点,影响协同选择的风险因素主要有生产制造型企业和第三方物流的地位与作用、协同各方投入与贡献度随时间推移产生的变化、外部产业政策及内部自适应等;在协同过程中,各参与企业所获得的收益与承担的风险与所投入的物流成本之间存在着正相关关系,且存在着选择临界点;模型演算出的协同选择临界点,可保障协同模型的长期性与稳定性。研究结果为物流协同选择研究提供了新思路,对企业协同选择决策具有借鉴意义。     

A business and ICT architecture for a logistics city

The city of Melbourne, Australia, stands to benefit from achieving the logistics city status. The planning theme of a logistics city is designed around achieving efficiencies and long term sustainability out of the legacy of dispersed groups of intensive “logistics activity areas”. This is not to re-invent solutions particularly in Melbourne, where the existence of a legacy logistics infrastructure and ad hoc growth has resulted in the business architecture that is constantly in the “catch-up” mode. This is seen as a unique opportunity for developing business models to meet the future challenges of the growth of trade, freight movement and maintaining economic, environmental and urban sustainability. Enterprise architecture will enable attention to be focused on the development of a collaborative business model, which will help to achieve efficiencies in view of the complex set of economic, social and environmental parameters. The logistics city business architecture responds to the shift to a services economy, which is generating different patterns of workforce travel to ensure good access to skilled workers, to other services, to business clients and to national and international markets.     

Bundling digitized logistics activities and its performance implications

Bundling information technology (IT) applications to support logistics activities provides a means for firms to improve their logistics performance. Grounded in the logistics management and management information systems literature, as well as the resource-based view (RBV) of the firm, this study empirically: (i) investigates if there exist digitized logistics activities bundles in firms; and if so, (ii) explores the association between digitized logistics activities bundles and logistics performance of firms in terms of logistics cost and logistics service improvements. We surveyed 227 trading firms in Hong Kong and performed a factor analysis of the survey data, from which we identified three digitized logistics activities bundles and found the sample firms were clustered into four types based on the patterns of their digitized logistics activities. We then carried out a MANOVA on the data, the results of which show that different patterns of digitizing logistics activities are associated with different logistics performance outcomes. Specifically, firms with more extensive digitized logistics activities bundles and utilizing them more intensively achieve better logistics performance. Academic and managerial implications for digitizing logistics activities to improve logistics performance are discussed.     

Inventory model for an inventory system with time-varying demand rate

The standard inventory problems of the multi-period have been modeled under different situations. Specifically we have considered the demand subjects of a continuous distribution and a discrete distribution, and whether the demand of each period is unchanged or not. A method to get an economic order quantity in inventory systems with discrete and unchanged demand was presented in a previous paper, and this method has been generalized to an inventory model with varying continuous demand. However, it was not achieved due to there being many classified cases in the general situations. In this article the above method is discussed in the case discrete demand to determine whether it increases or decreases from period to period. A theoretical method is presented by using previous results and some examples are given which suggest how the concept can handle on inventory system. In order to make the decision, an algorithm is also presented under some conditions, and examples are shown by using the computer software program, Mathematica, which helps to explain the findings. In general cases, we view the optimal policy in the inventory problems in only a few periods.     

丝绸之路经济带中道省区物流业与区域经济的耦合协调性研究

本文以2006~2015 年丝绸之路经济带中道10 省（市）区物流业与区域经济发展的相关数据为依据,构建耦合评价模型和空间自相关模型,分析丝绸之路经济带中道10 省（市）区物流业与区域经济发展的协调性关系问题。结果表明：丝路中道10 省（市）区物流业与区域经济发展水平呈现良好发展态势,协调性不断加强;物流业与区域经济耦合协调度有显著空间集聚性,整体呈“东强、中柔、西弱”的分布态势,地区分异化明显。建议推进均衡化发展,优化物流业自东向西辐射机制、大力增强中西部省区物流基础功能和产业带动能力,着力提升丝绸之路经济带中道物流与区域经济一体化协同水平。