The (non-)application of blockchain technology in the Greek shipping industry

The implementation of blockchain technology (BCT) is gaining traction in supply chain networks, revolutionising the operation of contemporary supply chains and reshaping the potential of business relationships. Empirical studies on blockchain adoption are scant because implementation across networks is in fairly early phase of development, yet evidence from empirical studies is highly desirable. This is one of the first studies of blockchain adoption in the Greek shipping industry, which has not so far been examined by the literature, in direct comparison to early adopters in other European countries such as Norway. The research examined eight Greek shipping companies using workshops with experienced supply chain personnel. Qualitative analysis identified the current position of these organisations in terms of blockchain adoption, by considering possible benefits and inhibitors to implementation. Despite benefits of automated processes and reduced paperwork as a result of smart contracts, findings show a reluctance to adopt BCT. That is, enterprise resource planning (ERP) transformations have left organisations fatigued and disinclined towards further systems development and resistant to subsequent change. Also, the exposure of shared information in the shipping nexus is considered to cause a threat to competitive survival.     

核心企业主导下乳制品全产业链质量管控GERT网络模型

乳制品质量安全是关系消费者健康的重大问题，乳制品质量管控是一项涵盖多环节、多主体的复杂系统工程；而要把质量管控措施落到实处，乳制品产业链的核心企业是关键。针对我国乳制品产业质量管控现状，构建了基于质量价值流动的乳制品全产业链质量管控GERT网络模型，并对"产业链主体未加强质量管控"、"各主体独立加强质量管控"以及"核心企业主导下全产业链质量管控"三种情境进行对比分析。研究表明，核心企业主导下全产业链质量管控具有明显优势；强化乳制品行业质量管控，须从政府层面、企业层面以及消费者层面采取对策，尤其要突出核心企业在此过程中的主导地位。     

Estimation and Properties of a Time-Varying EGARCH(1,1) in Mean Model

Time-varying GARCH-M models are commonly employed in econometrics and financial economics. Yet the recursive nature of the conditional variance makes likelihood analysis of these models computationally infeasible. This article outlines the issues and suggests to employ a Markov chain Monte Carlo algorithm which allows the calculation of a classical estimator via the simulated EM algorithm or a simulated Bayesian solution in only O(T) computational operations, where T is the sample size. Furthermore, the theoretical dynamic properties of a time-varying-parameter EGARCH(1,1)-M are derived. We discuss them and apply the suggested Bayesian estimation to three major stock markets.     

数字经济供给使用表:概念架构与编制实践研究

数字经济供给使用表是数字经济卫星账户的核心表式,具有统计协调和分析工具的双重作用,能够准确监测数字经济产业发展规模及传统产业与数字经济的融合程度。目前,国际上对数字经济供给使用表的研究尚处于初期探索阶段,还未有国家编制出基于实际数据的数字经济供给使用表,经济合作与发展组织(OECD)对数字经济供给使用表的理论框架进行了前瞻性探索,但系统的数字经济供给使用表构建指南还亟待完善。本文首先从供给和使用层面构建数字经济供给使用表概念框架,界定数字经济特征活动的概念和范围,梳理OECD 划分的数字经济供给使用表中的产品清单和数字经济产业分类;阐释数字经济最终消费、固定资本形成、贸易活动的内涵和种类。其次,围绕“产品×产业×特征活动”三重维度,设计数字经济供给使用表整体架构、阐明其核心指标。再次,编制数字经济供给使用表实例,剖析编制流程、总结编制要点。最后,提出结论和建议。本文尝试完善数字经济统计核算体系,为提出促进我国数字经济高质量发展的政策建议提供核算方法参考。     

Supply chain agility as an acclimatisation process to environmental uncertainty and organisational vulnerabilities: insights from British SMEs

Abstract

Even though supply chain agility (SCA) has been considered an essential concept in supply chain management (SCM) research, the way it is experienced and manifested, especially by small and medium-sized enterprises (SMEs), has received much less attention. Our purpose is to focus on SME organisational vulnerabilities in the context of increased environmental uncertainty, and explore how SCA is developed and applied by SMEs amid their vulnerabilities. By relying on insights from comparative case studies of three British SMEs, we examine SME SCA as an acclimatisation process and delve into SMEs’ experiences of facing environmental uncertainty while developing and applying SCA. Our findings highlight that organisational attitudes underlie how SMEs perceive environmental uncertainty, tackle organisational vulnerabilities and develop SCA as an acclimatisation process. Our findings also reveal that resource constraints, supply chain relationships, interorganisational power dynamics, and access to information play important roles in developing SCA.     

原产地多元化视角下的地方产业集群升级研究

地方产业集群升级是区域经济发展的重要研究主题,由于中国特别是东部地区产业集群具有"天生全球化"特质,基于价值链的集群升级理论在适用性上存在局限。本文以原产地多元化为切入点,依据产业集群嵌入全球价值链的程度,对其通过原产地多元化实现升级的途径进行探讨,并结合案例分析加以验证。进而提出基于原产地多元化实现地方产业集群升级的主要内容和政策建议,以期为现实的产业集群发展和区域经济政策制定提供启示。     

A note on “Coordinating a supply chain for deteriorating items with a revenue sharing and cooperative investment contract”

In this short note, we first improve the proof in Zhang et al. [1] to show the strict concavity of the unit time total profit of the whole supply chain with respect to preservation technology investment without approximation. We then generalize the model of Zhang et al. [1] to a broader class of market demand functions. Additionally, theoretical results are provided to illustrate the features of the proposed model.     

Business patterns within telecommunications

The global telecommunications changed from a number of co-operating national monopolies offering a restricted range of services to a competitive, growing market with players of many types and sizes, offering a large range of services. How can vertically integrated incumbents align themselves and their systems to best compete in this environment? Business patterns and enterprise modelling offer a tool to model a large organization as a number of smaller enterprises that can compete with and co-operate with smaller specialist players in the market. In order to identify enterprises, this paper proposes that there are only a limited number of types of enterprise (manufacturer, service supplier, reseller, that these enterprise types can only interact in a limited number of ways (component supply, aggregation supply, resell supply, trading, end-supply and commission). With the use of examples, this paper illustrates these types of enterprise and enterprise relationships, and how they can be combined to build both internal and external supply chains, and discusses some of the conclusions that can be drawn from this analysis.     

Predicting infectious disease outbreak risk via migratory waterfowl vectors

The spread of an emerging infectious disease is a major public health threat. Given the uncertainties associated with vector-borne diseases, in terms of vector dynamics and disease transmission, it is critical to develop statistical models that address how and when such an infectious disease could spread throughout a region such as the USA. This paper considers a spatio-temporal statistical model for how an infectious disease could be carried into the USA by migratory waterfowl vectors during their seasonal migration and, ultimately, the risk of transmission of such a disease to domestic fowl. Modeling spatio-temporal data of this type is inherently difficult given the uncertainty associated with observations, complexity of the dynamics, high dimensionality of the underlying process, and the presence of excessive zeros. In particular, the spatio-temporal dynamics of the waterfowl migration are developed by way of a two-tiered functional temporal and spatial dimension reduction procedure that captures spatial and seasonal trends, as well as regional dynamics. Furthermore, the model relates the migration to a population of poultry farms that are known to be susceptible to such diseases, and is one of the possible avenues toward transmission to domestic poultry and humans. The result is a predictive distribution of those counties containing poultry farms that are at the greatest risk of having the infectious disease infiltrate their flocks assuming that the migratory population was infected. The model naturally fits into the hierarchical Bayesian framework.