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21.
在全球经济一体化环境下,传统的管理模式、经营理念、业务方法已不能适应快速变化的市场运行。顾客(Customer)、竞争(Competition)和改变(Change)驱使企业发展进入新阶段。在灵活性与快速响应主宰的商业战场中,客户关系应用而生,业务流程重组和客户关系管理的结合似乎成了一种必然.  相似文献   
22.
Many see Nanotechnology as the technology that will underlie the next Schumpeterian wave creating new opportunities for wealth and job creation. Further it is a process based or materials technology. Yet all currently used models of innovation are based on assembled products or service products and these simply do not recognize the differences in materials products nor the “enabling” nature of Nanotechnologies. If nanotechnology is poised to become the economic engine of this millennium and if current models of innovation, which are utilized, by policy makers and firm based strategist alike are based on technology product paradigms that are dissimilar to the realities of nanotechnology and other process-based technologies then there is cause for concern.Here the authors provide a model and supporting cases demonstrating a new process or materials based innovation model that is based on the tight coupling between product and process innovation of not only Nanotechnology-based products but other process-based products. This is an important finding, because it identifies and remedies a gap in the literature associated with earlier process and product innovation models. For process-based products like materials, food, chemicals and nanotechnologies any change to the manufacturing processes results in significant changes in end product features. The implications of this model to practice are considered.  相似文献   
23.
We consider the normalized least squares estimator of the parameter in a nearly integrated first-order autoregressive model with dependent errors. In a first step we consider its asymptotic distribution as well as asymptotic expansion up to order Op(T−1). We derive a limiting moment generating function which enables us to calculate various distributional quantities by numerical integration. A simulation study is performed to assess the adequacy of the asymptotic distribution when the errors are correlated. We focus our attention on two leading cases: MA(1) errors and AR(1) errors. The asymptotic approximations are shown to be inadequate as the MA root gets close to −1 and as the AR root approaches either −1 or 1. Our theoretical analysis helps to explain and understand the simulation results of Schwert (1989) and DeJong, Nankervis, Savin, and Whiteman (1992) concerning the size and power of Phillips and Perron's (1988) unit root test. A companion paper, Nabeya and Perron (1994), presents alternative asymptotic frameworks in the cases where the usual asymptotic distribution fails to provide an adequate approximation to the finite-sample distribution.  相似文献   
24.
改革开放以来,我国迅速成为制造业大国,但还远远不是制造业的世界中心。只有认清我国制造业存在的预期利润低、结构不合理、产业链的低端定位、边际效应递减、研究与开发费用不足以及教育结构对制造业的瓶颈效应等问题,并对症下药,才能将我国的制造业真正做大做强。  相似文献   
25.
讨论了全低变工艺开发过程中遇到的一些问题和对策,对中、小氮肥企业进行技术改造具有一定的参考意义。  相似文献   
26.
By means of a straightforward application of empirical process theory, we show that S-estimators of multivariate location and covariance are asymptotically equivalent to a sum of independent vector and matrix valued random elements respectively. This provides an alternative proof of asymptotic normality of S-estimators and clearly explains the limiting covariance structure. It also leads to a relatively simple proof of asymptotic normality of the length of the shortest α-fraction.  相似文献   
27.
文章通过分析巴陵分公司煤代油工程的污水排放特性及技术条件,探讨了污水处理工艺的选择。  相似文献   
28.
基于六西格玛流程改进的库存管理优化   总被引:1,自引:0,他引:1  
孙一苇 《物流科技》2007,30(7):92-97
库存管理是企业用来控制实际库存问题的方法,主要帮助企业经营者确定何时补充订货、补充订货多少以及安全库存等问题。现有的库存控制研究往往只关注数学建模阶段的精确性,而对库存波动根源认识不足,导致数学模型越来越复杂、完善,但库存仍然居高不下、难以控制。本文针对该问题,提出了在库存管理中糅合六西格玛管理理念的思想,通过六西格玛方法揭示库存积压的根源,从源头着手,进行流程改进,从而达到库存优化、提高客户满意度的目的。文章通过实际案例证实了基于六西格玛理念的库存优化管理的有效性。  相似文献   
29.
VARMA (vector autoregressive moving average) processes are proposed for modelling cointegrated variables. For this purpose the echelon form is combined with the error correction form. Procedures for estimating the Kronecker indices which characterize the echelon form and for specifying the cointegration rank are discussed. The asymptotic distribution of the coefficient estimators is given. An example based o n US macroeconomic data illustrates the procedure and demonstrates its feasibility in practice.  相似文献   
30.
In the process of coding open-ended questions, the evaluation of interjudge reliability is a critical issue. In this paper, using real data, the behavior of three coefficients of reliability among coders, Cohen’s K, Krippendorff’s α and Perreault and Leigh’s I r are patterned, in terms of the number of judges involved and the categories of answer defined. The outcome underlines the importance of both variables in the valuations of interjudge reliability, as well as the higher adequacy of Perreault and Leigh’s I r and Krippendorff’s α for marketing and opinion research.  相似文献   
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