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21.
浅析石油化工项目产品市场分析   总被引:2,自引:0,他引:2  
市场分析是项目前期的重要工作之一,目前尚未赢得人们足够的重视。国外的投资咨询公司对石油化工项目的产品市场分析有其一套比较完整的操作程序和评估体系,以BOPP为案例介绍了市场分析的思路和方法,并且指出市场分析作为一种新的理念,必须进一步深化和细化,逐步加以完善。  相似文献   
22.
23.
Predicting the geo-temporal variations of crime and disorder   总被引:2,自引:0,他引:2  
Traditional police boundaries—precincts, patrol districts, etc.—often fail to reflect the true distribution of criminal activity and thus do little to assist in the optimal allocation of police resources. This paper introduces methods for crime incident forecasting by focusing upon geographical areas of concern that transcend traditional policing boundaries. The computerised procedure utilises a geographical crime incidence-scanning algorithm to identify clusters with relatively high levels of crime (hot spots). These clusters provide sufficient data for training artificial neural networks (ANNs) capable of modelling trends within them. The approach to ANN specification and estimation is enhanced by application of a novel and noteworthy approach, the Gamma test (GT).  相似文献   
24.
Nonstandard probability theory and stochastic analysis, as developed by Loeb, Anderson, and Keisler, has the attractive feature that it allows one to exploit combinatorial aspects of a well-understood discrete theory in a continuous setting. We illustrate this with an example taken from financial economics: a nonstandard construction of the well-known Black-Scholes option pricing model allows us to view the resulting object at the same time as both (the hyperfinite version of) the binomial Cox-Ross-Rubinstein model (that is, a hyperfinite geometric random walk) and the continuous model introduced by Black and Scholes (a geometric Brownian motion). Nonstandard methods provide a means of moving freely back and forth between the discrete and continuous points of view. This enables us to give an elementary derivation of the Black-Scholes option pricing formula from the corresponding formula for the binomial model. We also devise an intuitive but rigorous method for constructing self-financing hedge portfolios for various contingent claims, again using the explicit constructions available in the hyperfinite binomial model, to give the portfolio appropriate to the Black-Scholes model. Thus, nonstandard analysis provides a rigorous basis for the economists' intuitive notion that the Black-Scholes model contains a built-in version of the Cox-Ross-Rubinstein model.  相似文献   
25.
储雪俭 《物流技术》2006,(4):100-104
通过对仓储运作的调查诊断,来定义仓储操作中拥有广泛基础的可持续发展的优先管理权。以让每个企业能更方便的发现自身仓储操作中的问题,重新检查自身的库存系统,建设一套符合企业自身特点的仓储管理系统。  相似文献   
26.
Got milk? The rapid rise of China’s dairy sector and its future prospects   总被引:1,自引:0,他引:1  
This paper synthesizes recent research and new empirical findings to build a more comprehensive understanding of developments in China’s dairy sector. China’s tremendous rise in dairy demand has been driven by several mutually reinforcing factors: including rapid income growth, promotion by the government and dairy industry, changes in urban lifestyles, and the development of new, more sophisticated marketing channels. Domestic milk output has grown to satisfy rising demand largely by increasing the dairy herd. Substantial increases in productivity have been achieved through technology adoption, but there is evidence that the torrid growth has created inefficiencies because adaptations to marketing rules, infrastructure, and institutions have not kept pace with the changing environment. These results suggest there is ample room for future growth in both domestic milk production and dairy demand, but multinational firms and imported products will likely play and increasing role as China’s dairy market continues to develop.  相似文献   
27.
This article classified gas exploration risk on the basis of the characteristics of oil-gas exploration investment projects, which are internal systems risk and external non-systemic risk. It described each classification specifically and introduced the basic principles and mathematical model of the multi-factor hierarchical fuzzy comprehensive judgment in detail, and then researched the conducts the risk of the gas exploration with examples.  相似文献   
28.
This paper considers welfare analysis with therandom utility model (RUM) when perceptions ofenvironmental quality differ from objectivemeasures of environmental quality. Environmental quality is assumed to be anexperience good, so that while perceptions ofquality determine choices, ex postutility is determined by objective quality. Given this assumption, I derive a measure ofthe welfare impact of changes in environmentalquality, and I show how this new welfaremeasure differs from the traditional welfaremeasure developed by Hanemann (1982). This newwelfare measure provides an approach tomeasuring the value of information aboutenvironmental quality within the framework ofthe random utility model.  相似文献   
29.
Graphical models provide a powerful and flexible approach to the analysis of complex problems in genetics. While task-specific software may be extremely efficient for any particular analysis, it is often difficult to adapt to new computational challenges. By viewing these genetic applications in a more general framework, many problems can be handled by essentially the same software. This is advantageous in an area where fast methodological development is essential. Once a method has been fully developed and tested, problem-specific software may then be required. The aim of this paper is to illustrate the potential use of a graphical model approach to genetic analyses by taking a very simple and well-understood problem by way of example.  相似文献   
30.
What's So Special about China's Exports? A Comment   总被引:2,自引:0,他引:2  
Dani Rodrik argues that China's exports are unusually sophisticated for a country at its income level. He also claims that China's export sophistication reflects the government's successful industrial policy and has been instrumental in the recent acceleration of its economic growth. Although Rodrik's interpretation of China's economic growth is broadly correct, the accuracy of his empirical analysis is questionable. This note identifies several problems regarding the “export sophistication” index used in his empirical work and casts doubt on his analysis.  相似文献   
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