A Stochastic Frontier Production Function with Flexible Risk Properties

This paper considers a stochastic frontier production function which has additive, heteroscedastic error structure. The model allows for negative or positive marginal production risks of inputs, as originally proposed by Just and Pope (1978). The technical efficiencies of individual firms in the sample are a function of the levels of the input variables in the stochastic frontier, in addition to the technical inefficiency effects. These are two features of the model which are not exhibited by the commonly used stochastic frontiers with multiplicative error structures.An empirical application is presented using cross-sectional data on Ethiopian peasant farmers. The null hypothesis of no technical inefficiencies of production among these farmers is accepted. Further, the flexible risk models do not fit the data on peasant farmers as well as the traditional stochastic frontier model with multiplicative error structure.     

面向电子商务的现代物流管理信息系统的开发

结合现代物流技术发展趋势，分析探讨了面向电子商务的现代物流管理信息系统的开发技术路线，关键技术内容，功能体系结构设计及分层逻辑模型设计。     

我国建筑业全生命周期价值链的应用研究

长期以来,我国建筑业缺乏对全生命周期价值链管理的整体关注,价值链中各个环节相互脱节,没有共同的价值目标,导致了成本较高的现状。本文旨在通过对建筑业全生命周期价值链的分析,拓展我国建筑业成本管理的关注面。并通过工程总承包模式对现有价值链进行优化,把勘察、设计、施工归集在同一个主体下管理,提高用户对建筑产品的满意度,降低产品成本。     

Pure joint production and international trade: a note

This paper applies the principles of the neo-Ricardian (or Sraffian)theory of international trade to certain joint production systems.It is shown that, in contrast with single-product systems, (i)there is not always a pattern of international specialisation,which would entail the increase of the real wage rate in botheconomies, and (ii) the ‘law of comparative advantage’has no general validity. Furthermore, not only the existenceof such a pattern of specialisation but also the validity ofthis law depend on the values of the variables of distributionof income. The analysis is wholly based on two of the numericalexamples formulated by Bidard in 1997, and further generalisedin an elementary way only when this is considered necessary.     

Embedded industrial production systems: Lessons from waste management in zinc production

To meet the sustainability challenge private companies must implement corporate strategies and adopt novel technologies. The technical and social embeddedness of industrial production systems, however, complicates these systems' transition towards sustainability. In the paper, mechanisms and conditions are reported for the development and implementation of waste management options in embedded industrial production systems. The focus is on the Dutch zinc production industry, which had to deal with a major waste problem; the generation of jarosite. The industry's options were to increase the jarosite waste storage capacity, to develop a jarosite treatment process or to switch to a zinc-ore of low-iron content whereby no jarosite waste would be generated anymore. Required conditions appeared to be a combination of technological capability and technical embedding and favourable economics. Case study research, however, revealed that adequate stakeholder management is crucial to address social pressure exerted and to obtain external acceptance for any transition strategy. Whilst appropriate, internal technological capabilities are important, effective interactions with and enrolment of various firm-external actors are crucial. In the case of zinc, access to the heterogeneous external actor network was critical for the development of the jarosite treatment solution direction. In conclusion, both the technical, organizational and social embedding of new technologies are crucial for successful implementation.     

银行信用证议付及其追索权的法学解读

在法学视角下，信用证议付实质上是议付银行向信用证受益人（出口商）给付价值后买入信用证项下的汇票和整套单据的法律行为。议付不同于出口押汇。议付是一种买卖汇票和单据的行为，而出口押汇是一种以单据为质押的融资行为。议付单据遭到开证银行拒付，议付银行有权对信用证受益人（出口商）行使追索权。议付银行的这种追索权既可以来自于合同条款的约定，也可以来自于票据法所赋予的请求权。     

商业银行利率风险计量模型及实证分析--非平移收益曲线条件下的随机免疫策略

传统的久期理论建立在收益曲线平移等严格假设条件上，因而其在实践中的有效性大大降低了。根据Markowitz（1959）等理论可推导出：资产价格的总风险包括收益的方差和全久期向量两部分；假若商业银行采取现金中性（cash neutrality）的资产交易策略，风险计量模型可转换为线性规划问题，从而可以构建基于利率风险最小化模型的随机免疫策略。也就是说，引入随机免疫的理念来替代经典的免疫理论，通过实证分析得出：无现金交易条件下的随机免疫策略能够降低利率风险。     

基于人工神经网络的企业生产预警管理系统研究

企业生产预警管理是生产企业现代管理的一种新模式,它通过监测指标,对企业外部环境变化和生产管理活动进行综合评价,判断企业生产管理所处状态,并采取相应的预先控制对策,使企业生产管理活动始终处于“安全、有效”的管理模式。人工神经网络是广泛应用于众多学科的非线性模拟技术,文章将人工神经网络技术应用到企业生产预警管理中,根据影响生产管理的指标和分类标准随机生成有效的样本数据以建立人工神经网络模型。结果表明样本生成方法和应用人工神经网络技术进行企业生产预警管理评估的方法是合理并可行的。     

股票市场收益率波动长记忆性的分解及实证研究

目前股票市场长记忆性检验和建模方法，不能很好地消除短期记忆的影响，针对这一问题，本文提出寻找序列的突变点，通过将序列分解为只包含长记忆性部分和不包含长记忆性部分的序列分解技术，来排除短期记忆的影响。对上证指数和深圳成分指数收益率波动的长记忆性进行实证研究发现，将序列分解以后进行长记忆性检验，不仅可以得出长记忆性检验更为精确的结论，同时可以检验序列分解过程的效果。     

我国农产品物流落后原因初探

在我国，农产品物流很少有人关注，但是，由于农产品的物流落后使我国农产品的损失却大得惊人。这不仅极大地影响了农民收入水平的提高，还严重削弱了我国农产品的国际竞争力。本文对我国农产品物流落后的原因进行了全面、深入的探讨。