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991.
《Omega》2014
In this paper we use the nonparametric method of Data Envelopment Analysis (DEA) to obtain Pareto-Koopmans measures of technical efficiency of individual states over the years 1970–71 through 2000–01 in a multi-output, multi-input model of agricultural production. We disaggregate overall efficiency into two distinct components representing output and input efficiencies and identify the contribution of individual outputs and inputs to the measured level of overall efficiency. Because introduction of modern inputs has been a major component of the process of modernization of Indian agriculture, we examine to what extent different states succeeded in utilizing the modern inputs compared to the traditional inputs. Variations in the DEA efficiency scores across states and over years is explained in terms of differences in various institutional and demographic factors in a second stage regression analysis. 相似文献
992.
《Omega》2014
Allocation of the tasks in competitive market conditions at each echelon of the supply chain is an important activity in the supply chain. The task allocation problem, referred to as supply chain formation process, normally faces information asymmetry in the supply chain. The information asymmetry is caused by rational and intelligent players trying to maximize their own profit rather than opt for the supply chain profit as a whole. Thus, the process of allocating tasks in such situations becomes difficult and will result in externalities in the supply chain trades. These externalities can be internalized with present methodologies in the literature. In this paper, the major internalization methods in different contexts are considered. Lagrange relaxation and Vickery Clarke Groves (VCG) auction mechanism are explored in order to form a supply chain. This paper proposes the multi-stage auction mechanism analyzing two-way competitions, a Bertrand and Cournot competition where price per unit and quantity are the underlying two parameters in a utility analysis. To analyze the problem in real life, the industry example of Indian Railway Catering and Tourism Corporation Ltd. (IRCTC) procurement process has been taken which demonstrates the usability of the proposed framework. 相似文献
993.
基于贝叶斯正则化的TDBPNN模型在中国外贸预报中的应用及评估 总被引:6,自引:0,他引:6
基于相空间重构的非线性预报思想,建立一个时滞的BP神经网络模型(TDBPNN),采用贝叶斯正则化方法提高BP网络的泛化能力,并将该模型应用于中国进出口贸易的预测,结果证明改进的TDBPNN模型具有较好的泛化能力,准确拟合了进出口贸易发展的历史值和趋势。区别于一般的预测评价,认为非线性预测不仅要注重数据拟合和精度改进,而且应该能够反映被预报系统的非线性特征。在分析模型预测精度的同时,通过计算拟合序列和原序列的非线性特征量进行模型评价,证实预测模型能够合理地“捕捉”到产生原序列的非线性系统的动力学特征。 相似文献
994.
本文以14家同时发行H股与ADR,6家同时发行B股与ADR的上市公司为样本,利用GARCH(1,1)-MA(1)模型,探讨ADR与原股报酬波动的外溢效应,以了解我国证券市场与美国证券市场的整合程度。结果发现,我国H股与ADR之间存在报酬波动性的双向相关性,B股与ADR之间存在报酬波动性的单向相关性。本文认为,投资主体差异、市场发展程度不同以及汇率制度是三个影响我国市场和美国市场整合程度的主要因素。 相似文献
995.
In the history of warfare, there are a number of examples of strategic uses of asymmetric technologies. Consistent with history and theory, individuals, organizations and nations have spotted opportunities to employ information and communications technologies to gain and exploit asymmetric advantages and to counter asymmetric weaknesses. This article discusses various asymmetries associated with institutions, nations and organizations that influence the ICT-national security nexus. Regulative, normative and cognitive institutions in a country provide various mechanisms that affect the nature of positive and negative asymmetries. Nations and organizations also differ in terms of their capability to assimilate ICT tools to gain positive asymmetries and deal with vulnerabilities of negative asymmetries. Integrative approaches that combine policy and technological measures at various levels are likely to make the world more secure. 相似文献
996.
多项目管理在大型建筑企业工程项目中的应用研究 总被引:5,自引:0,他引:5
本文针对我国当前大型建筑施工企业的工程项目管理,对多项目管理的控制管理应用研究,通过建立项目办公室,管理区域市场,有效地协调分配现有的资源,解决需求的冲突,开发出可靠和可重复使用的系统。 相似文献
997.
Maria Brouwer 《Journal of Management and Governance》2005,9(3-4):237-255
Organizational innovation is essential to economic development. But, the way successful societies have organized new ventures
has been remarkably similar in both past and present. The commenda organizations of medieval Italy shared many characteristics
with modern startups that are financed by venture capital. Profit share contracts; limited liability and periodic reevaluations
are cases in point. Agency contracts in both types of ventures are designed to absorb the high uncertainty inherent to these
enterprises through risk sharing. Uncertainty prohibits a unique ex ante ranking order of investment projects and prompts
investors to look for hidden human capital. Equity finance is better equipped to even out unexpected losses and gains that
are inherent to uncertainty than debt finance. 相似文献
998.
Since the Last Planner System® (LPS) was devised in the early 90s, a number of studies have pointed out the need to understand the underlying theory in which it is based on. The Language-Action Perspective (LAP) has been suggested as a suitable approach to understand the management of commitments in the LPS. This paper aims to assess the contribution of LAP to understand construction planning and control systems based on LPS. Two case studies were carried out in different construction companies, both highly experienced on the use of LPS. The results reveal the role of LAP for creating explicit representations of commitment flows that can be used to explain the sources of complexity and failures in planning systems, as well as for describing the profile of planning and control meetings. 相似文献
999.
Smart manufacturing systems (SMSs) are envisioned to contain highly automated and IT-driven production systems. To address the complexity that arises in such systems, a standard and holistic model for describing its activities and their interrelationships is needed. This paper introduces a factory design and improvement (FDI) activity model and illustrates a case study of FDI in an electromechanical component factory. In essence, FDI is a reference activity model that encompasses a range of manufacturing system activities for designing and improving a factory during its initial development and also its operational phases. The FDI model shows not only the dependency between activities and manufacturing control levels but also the pieces of information and software functions each activity relies on. We envision that the availability of these pieces of information in digital form to integrate across the software functions will increase the agility of factory design and improvement projects. Therefore, our future work lies in contributing to standards for exchanging such information. 相似文献
1000.
Acrylamide forms primarily from a reaction between reducing sugars (e.g., glucose and fructose) and an amino acid (asparagine, Asn) formed naturally in foods, including potatoes. This reaction occurs when carbohydrate‐rich foods are heated at temperatures above 120 °C. Multiple potato varieties were transformed with potato genomic DNA that results in down‐regulation of the expression of the asparagine synthetase‐1 gene (Asn1), significantly reducing synthesis of free Asn, and consequently lowering the potential to form acrylamide during cooking. These potatoes with low acrylamide potential (LAP) were tested in agronomic trials, and processed into French fries and potato chips. Decreased levels of acrylamide were measured in these cooked food products when derived from LAP potatoes compared with those derived from conventional potatoes. These reductions can be directly attributed to reduction in Asn levels in the LAP potatoes. The corresponding average reduction in exposure to acrylamide from French fry and potato chip consumption is estimated to be 65%, which would amount to approximately a 25% reduction in overall dietary exposure. Considering that children consume nearly three times more acrylamide than adults on a per kg body weight basis, they would experience the most impact from the reduced acrylamide associated with LAP potatoes. The potential public health impacts, in context of dietary acrylamide exposure reduction, are discussed in this study. 相似文献