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111.
Bayesian techniques specify how to update beliefs about a variable given information on that variable or related variables. In many cases, statistical analyses also provide information about the relationship between variables, but the Borel Paradox prohibits many natural ways of updating beliefs conditioned on information about a relationship. This paper presents a method by which beliefs can be updated without violating the Borel Paradox under certain circumstances. We apply our approach to relationships specified by a statistical model (i.e., regression), and relationships described by statistical simulation. 相似文献
112.
Christian Grabner Heiko Hahn Ulrike Leopold-Wildburger Stefan Pickl 《European Journal of Operational Research》2009
For the analysis presented in this paper we use experiments to study human behavior in a simulation environment based on a simple Lotka–Volterra predator–prey ecology. The aim is to study the influence of different harvesting strategies and of certain personality traits derived from the Hamburg Personality Inventory (HPI) [Andresen, B., 2002. HPI – Hamburger Persönlichkeitsinventar. Hogrefe, Göttingen] on the outcome in terms of sustainability and economic performance. 相似文献
113.
冯珊 《华中科技大学学报(自然科学版)》1989,(3)
本文基于新古典经济学一般均衡理论,结合我国经济发展现状建立了多部门CGE经济模型。模型理论框架中,汇入了价格刚性和不完全市场机制。CCGE模型完成的多种想定方案仿真结果显示出综合意向强、因果关系确切的特点。可为发展战略决策提供理论依据。 相似文献
114.
Sampling errors can be divided into two classes, incorrect sampling and correct sampling errors. Incorrect sampling errors arise from incorrectly designed sampling equipment or procedures. Correct sampling errors are due to the heterogeneity of the material in sampling targets. Excluding the incorrect sampling errors, which can all be eliminated in practice although informed and diligent work is often needed, five factors dominate sampling variance: two factors related to material heterogeneity (analyte concentration; distributional heterogeneity) and three factors related to the sampling process itself (sample type, sample size, sampling modus). Due to highly significant interactions, a comprehensive appreciation of their combined effects is far from trivial and has in fact never been illustrated in detail. Heterogeneous materials can be well characterized by the two first factors, while all essential sampling process characteristics can be summarized by combinations of the latter three. We here present simulations based on an experimental design that varies all five factors. Within the framework of the Theory of Sampling, the empirical Total Sampling Error is a function of the fundamental sampling error and the grouping and segregation error interacting with a specific sampling process. We here illustrate absolute and relative sampling variance levels resulting from a wide array of simulated repeated samplings and express the effects by pertinent lot mean estimates and associated Root Mean Squared Errors/sampling variances, covering specific combinations of materials’ heterogeneity and typical sampling procedures as used in current science, technology and industry. Factors, levels and interactions are varied within limits selected to match realistic materials and sampling situations that mimic, e.g., sampling for genetically modified organisms; sampling of geological drill cores; sampling during off-loading 3-dimensional lots (shiploads, railroad cars, truckloads etc.) and scenarios representing a range of industrial manufacturing and production processes. A new simulation facility “SIMSAMP” is presented with selected results designed to show also the wider applicability potential. This contribution furthers a general exposé of all essential effects in the regimen covered by “correct sampling errors”, valid for all types of materials in which non-bias sampling can be achieved. 相似文献
115.
介绍了矢量控制系统中常用的几种坐标变换 ,用MATLAB实现坐标变换运算 ,并构建交流电机数学模型 ,可以方便的用于电机及其控制系统的研究 ,以Y型电机为例 ,给出了仿真结果 ,结果分析表明模型的有效性 相似文献
116.
卵黄油在超临界二氧化碳中的溶解度及其模拟 总被引:1,自引:0,他引:1
本文利用动态法及半连续装置,在温度35℃-75℃、压力25MPa-26MPa的条件下,进行了卵黄油在超临界二氧化碳中溶解度试验,并将试验结果用反传播神经网络方法进行模拟,社会网络能较好地模拟卵黄油在超临界二氧化碳中的溶解度。 相似文献
117.
磁场渗透导体壳的实验研究 总被引:2,自引:2,他引:0
本文叙述了测量阶跃脉冲垂直磁场和水平磁场渗透HL-1装置各种比例导体壳时间常数的方法。对空芯和铁芯变压器情况分别做了实验。给出了相应结果。 相似文献
118.
本文首先对物流仿真软件Flexsim介绍进行了简要的概述,然后介绍了Flexsim的运作流程,最后利用Flexsim对一个简单的配送中心进行了仿真,通过仿真结果可知Flexsim对提高物流配送中心的效率,降低成本具有积极的作用。 相似文献
119.
The class of generalized pattern search (GPS) algorithms for mixed variable optimization is extended to problems with stochastic objective functions. Because random noise in the objective function makes it more difficult to compare trial points and ascertain which points are truly better than others, replications are needed to generate sufficient statistical power to draw conclusions. Rather than comparing pairs of points, the approach taken here augments pattern search with a ranking and selection (R&S) procedure, which allows for comparing many function values simultaneously. Asymptotic convergence for the algorithm is established, numerical issues are discussed, and performance of the algorithm is studied on a set of test problems. 相似文献
120.
岑群霞 《温州大学学报(自然科学版)》2008,(2):64-69
英汉语语言体系(特别是语音特征)的不同决定了英汉语言语并置方面的不同,特别是语音并置中的押韵有所不同,汉语多是元音押韵。而英语则主要以辅音和辅音群押韵为特色。汉语里还包含了特有的词汇并置——仿词和语法及语义并置——对偶。 相似文献