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51.
作者在分析了影响汛前和汛后潼关高程变化值的因素的基础上,利用改进BP网络模型对非特征汛期和汛期潼关高程的变化值进行了计算。计算中不采用潼关的绝对高程,而用高程的变化量作为网络的较出物正量,从而减少计算误差,同时又能客观地考虑各影响因子的作用。改进后的BP模型学习时间短,精度满足要求。用该模型计算的潼关高程变化趋势与实际水库调度运行中的高程基本吻合。  相似文献   
52.
认股权证作为一种长期资金的筹资方式 ,其资本成本必须予以考虑。但是使用传统资本成本计算方法不能反映其真实成本。本文尝试使用B -S和CAPM模型来计算其资本成本 ,并用实例说明  相似文献   
53.
Price variations at speculative markets exhibit positive autocorrelationand cross correlation. Due to large parameter spaces necessaryfor joint modeling of variances and covariances, multivariateparametric volatility models become easily intractable in practice.We propose an adaptive procedure that identifies periods ofsecond-order homogeneity for each moment in time. To overcomethe high dimensionality of the problem we transform the multivariateseries into a set of univariate processes. We discuss thoroughlythe implementation of the adaptive technique. Theoretical andMonte Carlo results are given. We provide two applications ofthe new method. For a bivariate exchange rate series we comparethe multivariate GARCH approach with our method and find thelatter to be more in line with the underlying assumption ofindependently distributed innovations. Analyzing a 23-dimensionalvector of asset returns we underscore the case for adaptivemodeling in high-dimensional systems.  相似文献   
54.
This paper presents a vintage capital model assuming putty–clay investment and perfect foresight. The model is written in discrete time and is simulated by using a second order relaxation algorithm. By computing the eigenvalues of the dynamic system, we have checked the conditions of existence and uniqueness of a solution (Blanchard and Kahn's conditions) and identified the echo effect that characterizes vintage capital models and the related dynamics of creation and destruction. By calibrating the model on French data, it has been proved useful to explain the medium-term movements in the distribution of income in France during the last three decades.  相似文献   
55.
支流影响下的水库水温预测模型   总被引:3,自引:1,他引:2       下载免费PDF全文
采用宽度平均的立面二维水温模型,通过分析支流和主库之间的相互影响,提出了支流与主库耦合的简化方法,建立了考虑支流影响的水库水温模型。在考虑有无支流影响的条件下,对水库水温分布、水库下泄水温和坝前垂向水温分布均作了比较,结果表明支流对水库水温分布有一定的影响,所建立支流与主库耦合的立面二维水温模型能够较好地反映存在支流影响的水库水温分布,预测水库水温分布比较合理。  相似文献   
56.
Negotiation support using the Graph Model for Conflict Resolution   总被引:1,自引:1,他引:0  
The Graph Model for Conflict Resolution is a flexible methodology for systematically studying strategic conflicts in the real world, and is therefore a natural tool for negotiation support. The basic definitions underlying the graph model are reviewed, and the techniques for analysis and interpretation are discussed. The modeling and analysis of a case study, an international trade negotiation concerning the export of Canadian softwood lumber to the United States, are used to demonstrate the practical application of the Graph Model for Conflict Resolution as a negotiation support tool. The modeling and analysis is carried out using the GMCR software system. The ability of the Graph Model for Conflict Resolution to provide insights and advice to negotiators is emphasized.  相似文献   
57.
This paper demonstrates howadditional rents are generated in a fisherycharacterized by intraseasonal variation infish characteristics, including size,condition, and composition. Based on anexpanded conceptual model of the optimalharvest rule, fish characteristics affect preand post harvest production yields and outputprices. A dynamic empirical model, which uses asystem of quality characteristics and anhedonic equation, illustrates the complexrelationships and management choices associatedwith internalizing seafood qualitycharacteristics in a hake fishery. The modelretains the regulated open access managementsystem, but controls intertemporal andintersectoral quotas, production portfolios,and total allowable catch. Results demonstratethat including revenue-side effects frominternalizing fish quality can generatesignificantly greater rents and reduce therelative benefits of increased productionyields. If excluded, bioeconomic models canunderestimate the level of regulatory rentdissipation and overemphasize managementobjectives such as full utilization, whichcould misdirect processing decisions and resultin a suboptimal resource management plan.Implications for data collection,multidisciplinary analysis, and improvements inmarine resource management are discussed.  相似文献   
58.
In this progress report, we first indicate the origins and early development of the Marshallian macroeconomic model (MMM) and briefly review some of our past empirical forecasting experiments with the model. Then we present recently developed one-sector, two-sector and n-sector models of an economy that can be employed to explain past experience, predict future outcomes and analyze policy problems. The results of simulation experiments with various versions of the model are provided to illustrate some of its dynamic properties that include “chaotic” features. Last, we present comments on planned future work with the model.  相似文献   
59.
本文分析了在知识经济兴起的环境下我国现行会计模式存在的缺陷,并根据知识经济发展的历程以及我国目前工业经济与知识经济并存的现状,提出了一种能适应两种经济形态的兼容性会计模式,最后指出了目前实施该模式尚存在的制约因素。  相似文献   
60.
Aid, policy and growth in post-conflict societies   总被引:1,自引:0,他引:1  
Countries emerging from civil war attract both aid and policy advice. This paper provides the first systematic empirical analysis of aid and policy reform in the post-conflict growth process. It is based on a comprehensive data set of large civil wars, and covers 17 societies that were in their first decade of post-conflict economic recovery. We first investigate whether the absorptive capacity for aid is systematically different in post-conflict countries. We find that during the first 3 post-conflict years absorptive capacity is no greater than normal, but that in the rest of the first decade it is approximately double its normal level. Thus, ideally, aid should phase in during the decade. Historically, aid has not, on average, been higher in post-conflict societies, and indeed it has tended to taper out over the course of the decade. We then investigate whether the contribution of policy to growth is systematically different in post-conflict countries, and in particular, whether particular components of policy are differentially important. For this we use the World Bank policy rating database. We find that growth is more sensitive to policy in post-conflict societies. Comparing the efficacy of different policies, we find that social policies are differentially important relative to macroeconomic policies. However, historically, this does not appear to have been how policy reform has been prioritized in post-conflict societies.  相似文献   
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