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101.
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。  相似文献   
102.
The purpose was to assess RDS estimators in populations simulated with diverse connectivity characteristics, incorporating the putative influence of misreported degrees and transmission processes. Four populations were simulated using different random graph models. Each population was “infected” using four different transmission processes. From each combination of population x transmission, one thousand samples were obtained using a RDS-like sampling strategy. Three estimators were used to predict the population-level prevalence of the “infection”. Several types of misreported degrees were simulated. Also, samples were generated using the standard random sampling method and the respective prevalence estimates, using the classical frequentist estimator. Estimation biases in relation to population parameters were assessed, as well as the variance. Variability was associated with the connectivity characteristics of each simulated population. Clustered populations yield greater variability and no RDS-based strategy could address the estimation biases. Misreporting degrees had modest effects, especially when RDS estimators were used. The best results for RDS-based samples were observed when the “infection” was randomly attributed, without any relation with the underlying network structure.  相似文献   
103.
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.  相似文献   
104.
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.  相似文献   
105.
基于供应链集成的网络式新产品开发,不是从一个企业或企业集团层面看,而是从整个产业的层面看,那就是新产品开发是由产业内价值链相关各企业及企业外部研发资源,利用企业间的互动机制,相互创意激发及技术交流而产生新产品的一种模式,这种模式的最大优势是全体参与者的共同参与,发挥全体参与者团体作用的优势,强调产品开发流程,以产出为衡量基准,强调“产出成本效率”的业绩评估体系以及通过对外部资源的充分利用,强调“资源优化和无缝对接”和有效配套管理。  相似文献   
106.
边远民族地区应本着科学发展观,努力发展本地区的民族特色工业。边远民族地区发展工业经济应遵循以资源市场为导向、延长产业链,发展特色产业等,正确处理好工业经济与社会发展、三次产业之间以及经济发展与环境保护之间的关系。  相似文献   
107.
We study competition and coordination in a supply chain in which a single supplier both operates a direct channel and sells its product through multiple differentiated retailers. We study analytically the supply chain with symmetric retailers and find that the supplier prefers to have as many retailers as possible in the market, even if the retailers' equilibrium retail price is lower than that of the supplier, and even if the number of retailers and their cost or market advantage prevent sales through the direct channel. We find that the two‐channel supply chain may be subject to inefficiencies not present in the single‐channel supply chain. We show that several contracts known to coordinate a single‐channel supply chain do not coordinate the two‐channel supply chain; thus we propose a linear quantity discount contract and demonstrate its ability to perfectly coordinate the two‐channel supply chain with symmetric retailers. We provide some analytical results for the supply chain with asymmetric retailers and propose an efficient solution approach for finding the equilibrium. We find numerically that the supplier still benefits from having more retailers in the market and that linear quantity discount contracts can mitigate supply chain inefficiency, though they no longer achieve perfect coordination.  相似文献   
108.
We study the logistics problem faced by Regional Branches (RBs) of a central bank in managing the currency supply under security concerns. While making banknote supply decisions to Sub‐Branches (SBs), the management of RB must achieve two goals simultaneously: (i) guarantee that each SB has sufficient inventories of all denominations of banknotes to satisfy the demands from all commercial banks within its service area, and (ii) control the annual spending on this banknote supply operation. Due to security concerns, the following methods are implemented in the process of transporting banknotes: (i) the capacity of a cash truck is limited by the total face value (instead of the physical space) of banknotes, and (ii) empty decoy trucks are deployed along with the trucks filled with banknotes. After deriving a polynomial‐time strategy to guarantee an optimal solution for the special Bin‐Packing Problem faced in this study, we provide an exact formulation for the RB's supply planning problem. We also propose several polynomial‐time algorithms for deriving either optimal or near‐optimal solutions for the problem under different settings. Using the weekly demand data obtained from the central bank, we verify the performance of our algorithms, and analyze the impacts of changes in these features and in the fleet capacity on the total cost incurred by an RB under various scenarios.  相似文献   
109.
在单个拥有线下传统批发及线上直销双渠道的制造商和单个零售商组成的供应链中,基于供应链成员博弈权力的差异,构建制造商占优或零售商占优的两类Stackelberg博弈及双方同等权力的Nash博弈模型,分析了三种博弈权力结构对供应链成员价格,需求和利润的影响。研究发现:当制造商线下传统批发渠道所占市场份额较小时,(1)渠道交叉价格弹性系数为0时和不为0时,三种博弈权力结构对制造商双渠道供应链均衡解的影响具有一定的鲁棒性;(2)三种博弈权力结构下,制造商线上直销渠道价格相同;两类Stackelberg博弈权力结构下,线下传统批发渠道价格相同且大于Nash博弈下的传统渠道价格;制造商批发价格随其博弈主导地位下降逐渐降低;(3)当渠道交叉价格弹性系数为0时,三种博弈权力结构对线上直销渠道需求的影响是无差异的;当渠道间交叉价格弹性系数不为0时,两类Stackelberg博弈权力结构下的线下传统批发渠道需求相同且小于Nash博弈下的传统渠道需求,线上直销渠道需求相同且大于Nash博弈下的线上直销渠道需求;(4)三种博弈策略下,制造商收益及零售商收益随其博弈主导地位下降逐渐降低;Nash博弈下,供应链总利润最大。  相似文献   
110.
本文以新制度理论与交易成本理论进行对话,从合法性视角构建中国情境下制度环境、风险感知与供应链网络治理模式选择之间影响机理的理论模型。通过问卷调查的方式收集117份有效问卷,并采用结构方程模型方法实证检验制度环境、风险感知对供应链网络治理模式的"形塑"作用。研究结果表明,制度环境是影响供应链网络治理模式选择的重要因素,强制制度对供应链网络治理模式选择具有显著影响,规范制度的影响作用不显著。在供应链网络治理模式选择过程中关系风险感知具有完全中介作用,而绩效风险感知具有部分中介作用。  相似文献   
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