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911.
基于语言评价信息的知识资本要素识别方法   总被引:2,自引:0,他引:2  
知识资本是组织创造价值和获取竞争优势的关键资源, 其要素通常具有复杂的关联性, 如何识别知识资本的核心要素、原因要素和结果要素,对于组织进行知识资本管理具有重要意义.本文在构建了知识资本要素识别体系的基础上,借鉴决策试验和评价实验室报告的思想提出了一种基于语言评价信息的知识资本要素识别方法,通过处理和集结专家针对知识资本要素关联给出的语言评价信息,对知识资本要素进行排序与归类.最后通过一个实例分析说明了该方法的应用, 并说明了如何根据识别结果制定相应的策略以便进行知识资本的投资和控制.  相似文献   
912.
基于社会网络的舆情传播模型构建与分析   总被引:4,自引:0,他引:4  
本文考虑个体间的相互作用,提出了一个基于社会网络分析的舆情传播模型.模型假设网络中每个个体的初始状态只有两种情况,并且在单位时间步内只选择一个邻居进行交流,并以概率λ接受该邻居的意见.解析结果显示存在概率λc使得网络中持某种观点人数比例的期望值是一个常数,而其它状态下系统中所有个体的意见都会达成一致.本模型有助于衡量某给定社会网络中舆论传播的快慢程度.  相似文献   
913.
In this paper, we complete the global qualitative analysis of the well-known FitzHugh–Nagumo neuronal model. In particular, studying global limit cycle bifurcations and applying the Wintner–Perko termination principle for multiple limit cycles, we prove that the corresponding dynamical system has at most two limit cycles.  相似文献   
914.
An issue that has received little attention in the Data Envelopment Analysis literature is the decomposition of profit inefficiency by means of measures that account all sources of technical inefficiency. In this paper we introduce a new way to measure and decompose profit inefficiency through weighted additive models. All our results are derived from a new Fenchel-Mahler inequality using duality theory.  相似文献   
915.
对不锈钢管件无模拉伸变形速度场及力能参数进行了理论及实验研究.分析了不锈钢管件无模拉伸的变形模型、速度场以及力能参数的影响因素及影响规律,采用上限法确定了不锈钢管件无模拉伸速度场及力能参数物理模型,填补了国内外关于不锈钢管件无模拉伸变形及力能参数物理模型研究的空白.为不锈钢管件无模拉伸工艺工业化应用奠定基础.  相似文献   
916.
我国生猪年度供给量预测研究   总被引:1,自引:0,他引:1  
在运用协整检验、成本分析等方法对生猪供给量的影响因素进行分析的基础上,综合运用了回归分析、专家经验分析、指数平滑、情景预测等预测和决策方法,对我国2010-2012年的生猪年度供给量进行了预测.预测结果表明,在不发生影响生猪供给的重大突发事件的情况下,2010-2012年我国生猪产量将呈逐年上升的趋势.  相似文献   
917.
Efficient pricing of discrete Asian options   总被引:2,自引:0,他引:2  
Asian options are popular path-dependent financial derivatives. This paper uses lattices to price fixed-strike European-style Asian options that are discretely monitored. The algorithm proposed can also be applied to floating-strike Asian options as well because fixed-strike and floating-strike Asian options are related through an equation. The discretely monitored version is usually found in practice instead of the continuously monitored version usually encountered in the literature. This paper presents the first provably quadratic-time convergent lattice algorithm for pricing fixed-strike European-style discretely monitored Asian options. It is the most efficient lattice algorithm with convergence guarantees. The algorithm relies on the Lagrange multipliers to choose the number of states for each node of the lattice. Extensive numerical experiments and comparisons with many existing numerical methods confirm the performance claims and the competitiveness of our algorithm. This result places fixed-strike European-style discretely monitored Asian options in the same complexity class as vanilla options.  相似文献   
918.
Our aim in this paper, is first constructing a Lyapunov function to prove the global stability of the unique smoking-present equilibrium state of a mathematical model of smoking. Next we incorporate random noise into the deterministic model. We show that the stochastic model established in this paper possesses non-negative solutions as this is essential in any population dynamics model. Then a stochastic Lyapunov method is performed to obtain the sufficient conditions for mean square and asymptotic stability in probability of the stochastic model. Our analysis reveals that the stochastic stability of the smoking-present equilibrium state, depends on the magnitude of the intensities of noise as well as the parameters involved within the model system.  相似文献   
919.
In this paper, the asymptotic solution for the similarity equation of the laminar flow in a porous pipe with suction at expanding and contracting wall has been obtained using the singular perturbation method. However, this solution neglects exponentially small terms in the matching process. To take into account these exponentially small terms, a method involving the inclusion of exponentially small terms in a perturbation series was used to find the two solutions analytically. The series involving the exponentially small terms and expansion ratio predicts dual solutions. Furthermore, the result indicates that the expansion ratio has much important influence on the solutions. When the expansion ratio is zero, it is a special case that Terrill has discussed.  相似文献   
920.
Host migration among discrete geographical regions is demonstrated as an important factor that brings about the diffusion and outbreak of many vector-host diseases. In the paper, we develop a mathematical model to explore the effect of host migration between two patches on the spread of a vector-host disease. Analytical results show that the reproduction number R0 provides a threshold condition that determines the uniform persistence and extinction of the disease. If both the patches are identical, it is shown that an endemic equilibrium is locally stable. It is also shown that a unique endemic equilibrium, which exists when the disease cannot induce the death of the host, is globally asymptotically stable. Finally, two examples are given to illustrate the effect of host migration on the spread of the vector-host disease.  相似文献   
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