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991.
逻辑系统G3在非均匀概率空间下命题的真度理论 总被引:2,自引:0,他引:2
在离散概率测度空间下定义了三值逻辑(p,q,r)测度,并相应地定义了命题逻辑系统中公式的真度概念;在三值逻辑(1/6.1/3.1/2)测度和(1/7.2/7.4/7)测度下证明了命题逻辑系统G3中全体公式的真度值之集在[0.1]上是稠密的,并给出真度的表达式;利用真度定义公式的相似度和一种伪距离,为—般离散概率空间下三值命题的近似推理理论提供一种可能的框架. 相似文献
992.
Attaining reliable gradient profiles is of utmost relevance for many physical systems. In many situations, the estimation of the gradient is inaccurate due to noise. It is common practice to first estimate the underlying system and then compute the gradient profile by taking the subsequent analytic derivative of the estimated system. The underlying system is often estimated by fitting or smoothing the data using other techniques. Taking the subsequent analytic derivative of an estimated function can be ill-posed. This becomes worse as the noise in the system increases. As a result, the uncertainty generated in the gradient estimate increases. In this paper, a theoretical framework for a method to estimate the gradient profile of discrete noisy data is presented. The method was developed within a Bayesian framework. Comprehensive numerical experiments were conducted on synthetic data at different levels of noise. The accuracy of the proposed method was quantified. Our findings suggest that the proposed gradient profile estimation method outperforms the state-of-the-art methods. 相似文献
993.
Krishna K. Saha B. C. Sutradhar 《Annals of the Institute of Statistical Mathematics》1999,51(2):301-322
Based on a small correlations approach, this paper deals with the probability distributions of the order statistics under a general Gaussian model with unequal (positive or negative) correlations. Illustrations are given for the cluster data those follow suitable antedependence models. 相似文献
994.
Esther Frostig 《Operations Research Letters》2018,46(2):211-214
The dual risk model describes the surplus of a company with fixed expense rate and occasional random income inflows, called gains. Consider the dual risk model with two streams of gains. Type I gains arrive according to a Poisson process, and type II gains arrive according to a general renewal process. We show that the survival probability of the company can be expressed in terms of the survival probability in a dual risk process with renewal arrivals with initial reserve 0, and the survival probability in the dual risk process with Poisson arrivals in finite time. 相似文献
995.
Amit Wason 《Optik》2010,121(16):1478-1486
In this paper, low-complexity mathematical model has been developed which is used for the calculation of the blocking probability of network and this model does not require any simulation statistics. The implementation of the model proposed has less complexity and the computation used in this model is quite efficient. The routing algorithm has also been proposed in this paper depending upon the proposed model, which is very efficient in calculation and minimization of the blocking probability. This algorithm suggests an optimum path as a solution to routing problem. The wavelength assignment technique has also been suggested in this paper to minimize the blocking probability. The proposed model and algorithms can be implemented on different network topologies. Furthermore, the model, routing algorithm and wavelength assignment technique is also used to evaluate the blocking performance of NSFNet and EUPAN Network topology and hence used to improve its performance on the basis of the blocking probability. 相似文献
996.
Optical burst switching (OBS) has been considered as the gate through which the envisaged world of optical Internet will be conquered by implementing Internet Protocol (IP) software directly over a wavelength-division-multiplexing (WDM) optical layer (IP/WDM). The main feature for designing next generation optical networks is protecting and restoring high capacity WDM networks from the failures. Quick detection, identification and restoration make networks more strong and consistent even though the failures cannot be avoided. Hence, it is necessary to develop fast, efficient and dependable fault localization or detection mechanisms. In this paper, an efficient scheme for OBS networks has been proposed to provide fast restoration of links with minimum delay as well as blocking probability. By simulation results, it is shown that the proposed OBS scheme achieve less blocking probability and delay while getting higher throughput in comparison to conventional schemes. 相似文献
997.
区间数权向量排序方法研究 总被引:1,自引:0,他引:1
通过引入二元分布函数对一对区间数权重进行排序,从而确定一系列权重相对重要区间的次序.并对此方法给出了实例计算. 相似文献
998.
不允许卖空的组合证券投资策略的确定 总被引:3,自引:0,他引:3
以Markowitz的均值——方差模型的理论为基础,研究了组合证券投资策略确定过程中的两个主要问题:投资对象的选择方法和风险选择方法 相似文献
999.
VMI条件下具有复合二项随机需求的销售商库存策略研究 总被引:1,自引:0,他引:1
考虑一个典型的单一产品的二级供应链系统:单供应商对单销售商,假定系统中销售商的需求分布为复合二项分布,未满足的需求机会损失;补货间隔时间为一随机变量.本文采用概率方法对销售商的需求分布、期望缺货、期望库存周期及库存的稳定性分布进行研究的基础上,构建了使单位时间内销售商的期望库存成本费用最小的库存模型,由此模型便可确定VMI模式下供应商对销售商的库存补货参数s和S,并且给出了在补货响应时间为泊松分布的情况下模型的求解算法,还给出了及时补货响应情况下的5个算例.为补货策略的实施提供了一种简单易于控制的思路和方法. 相似文献
1000.
Mixtures of truncated exponentials (MTE) potentials are an alternative to discretization for representing continuous chance variables in influence diagrams. Also, MTE potentials can be used to approximate utility functions. This paper introduces MTE influence diagrams, which can represent decision problems without restrictions on the relationships between continuous and discrete chance variables, without limitations on the distributions of continuous chance variables, and without limitations on the nature of the utility functions. In MTE influence diagrams, all probability distributions and the joint utility function (or its multiplicative factors) are represented by MTE potentials and decision nodes are assumed to have discrete state spaces. MTE influence diagrams are solved by variable elimination using a fusion algorithm. 相似文献