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主成分分析法在非寿险保险公司偿付能力影响因素中的应用 总被引:4,自引:0,他引:4
本文运用主成分分析法对非寿险保险公司偿付能力诸多影响因素进行分析,简化成几个综合的成分,所得结果为保险监管部门和保险公司制定切实有效的管理策略,提供有价值的参考。 相似文献
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本文根据矩阵和逐步回归分析的基本原理,利用电子计算机对影响原煤全员效率的诸多因素进行多元分析.通过数据处理,找出了影响全员效率的主要因素,为预测原煤全员效率提供了数量化依据. 相似文献
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安全生产对于煤矿企业至关重要,本研究将政府、煤矿企业和员工纳入演化博弈模型中,探究三方主体间决策的博弈关系和演化路径。研究表明:政府、煤矿企业和员工的决策向理想状态的演化过程受到诸多因素的影响,不同因素取值范围对三方主体向理想状态收敛速度产生差异化影响;当满足一定条件时,三方主体的决策行为能够演化为理想状态,政府有效监管能够促进企业由惩罚型向激励型模式转化,激励型模式能够有效激发员工安全主动行为。以期为政府制定安全监管决策、企业转化安全生产管理模式、员工激发安全主动行为提供有益的建议。 相似文献
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产、学、研合作是一种加快科技成果向现实生产力转化,促进科技与经济密切结合的有效途径。在我国目前逐步确立的社会主义市场经济体制下,政府的行为及其配套政策对产、学、研合作起着至关重要的作用。因此研究和探讨符合我国实际情况的官、产、学、研相结合的技术开发体系与运作机制是极为现实的问题。本文的研究与探讨旨在能为解决和改善这一问题提供一些参考。 相似文献
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基于AHP-Entropy方法的科技成果转化绩效评价 总被引:4,自引:0,他引:4
科技成果的转化绩效优劣需要从多个层次、多个视角进行考核,本文从转化成果的经济效益、社会效益、环境效益和扩散效应等四个方面对科技成果转化绩效进行评价,评价体系的建立力求突出指标的精炼性和数据的可获性,借助AHP-Entropy方法并结合调查数据开展实证分析,阐述了评价方法的操作步骤且验证了评价体系的科学性和实践可行性。 相似文献
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Christian Gehrmann 《Designs, Codes and Cryptography》1998,15(1):67-86
Authentication codes are used to protect communication against a malicious adversary. In this paper we investigate unconditionally secure multiround authentication schemes. In a multiround scheme a message is authenticated by passing back and forth several codewords between the sender and receiver. We define a multiround authentication model and show how to calculate the probability of a successful attack for this model. We prove the security for a 3-round scheme and give a construction for the 3-round scheme based on Reed-Solomom codes. This construction has a very small key size for even extremely large messages. Furthermore, a secure scheme for an arbitrary number of rounds is given. We give a new upper bound for the keys size of an n-round scheme. 相似文献
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Stuart G. Baker 《Journal of computational and graphical statistics》2013,22(1):63-76
Abstract A simple matrix formula is given for the observed information matrix when the EM algorithm is applied to categorical data with missing values. The formula requires only the design matrices, a matrix linking the complete and incomplete data, and a few simple derivatives. It can be easily programmed using a computer language with operators for matrix multiplication, element-by-element multiplication and division, matrix concatenation, and creation of diagonal and block diagonal arrays. The formula is applicable whenever the incomplete data can be expressed as a linear function of the complete data, such as when the observed counts represent the sum of latent classes, a supplemental margin, or the number censored. In addition, the formula applies to a wide variety of models for categorical data, including those with linear, logistic, and log-linear components. Examples include a linear model for genetics, a log-linear model for two variables and nonignorable nonresponse, the product of a log-linear model for two variables and a logit model for nonignorable nonresponse, a latent class model for the results of two diagnostic tests, and a product of linear models under double sampling. 相似文献
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Pedro J. de Rezende Flávio K. Miyazawa Anderson T. Sasaki 《Operations Research Letters》2013,41(5):552-555
We present PTASs for the disk cover problem: given geometric objects and a finite set of disk centers, minimize the total cost for covering those objects with disks under a polynomial cost function on the disks’ radii. We describe the first FPTAS for covering a line segment when the disk centers form a discrete set, and a PTAS for when a set of geometric objects, described by polynomial algebraic inequalities, must be covered. The latter result holds for any dimension. 相似文献
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The classical Fermat-Weber problem is to minimize the sum of the distances from a point in a plane tok given points in the plane. This problem was generalized by Witzgall ton-dimensional space and to allow for a general norm, not necessarily symmetric; he found a dual for this problem. The authors
generalize this result further by proving a duality theorem which includes as special cases a great variety of choices of
norms in the terms of the Fermat-Weber sum. The theorem is proved by applying a general duality theorem of Rockafellar. As
applications, a dual is found for the multi-facility location problem and a nonlinear dual is obtained for a linear programming
problem with a priori bounds for the variables. When the norms concerned are continuously differentiable, formulas are obtained
for retrieving the solution for each primal problem from the solution of its dual. 相似文献
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A population-based cohort consisting of 126,141 men and 122,208 women born between 1874 and 1931 and at risk for breast or colorectal cancer after 1965 was identified by linking the Utah Population Data Base and the Utah Cancer Registry. The hazard function for cancer incidence is estimated from left truncated and right censored data based on the conditional likelihood. Four estimation procedures based on the conditional likelihood are used to estimate the age-specific hazard function from the data; these were the life-table method, a kernel method based on the Nelson Aalen estimator, a spline estimate, and a proportional hazards estimate based on splines with birth year as sole covariate.The results are consistent with an increasing hazard for both breast and colorectal cancer through age 85 or 90. After age 85 or 90, the hazard function for female breast and colorectal cancer may reach a plateua or decrease, although the hazard function for male colorectal cancer appears to continue to rise through age 105. The hazard function for both breast and colorectal cancer appears to be higher for more recent birth cohorts, with a more pronounced birth-cohort effect for breast cancer than for colorectal cancer. The age specific for colorectal cancer appears to be higher for men than for women. The shape of the hazard function for both breast and colorectal cancer appear to be consistent with a two-stage model for spontaneous carcinogenesis in which the initiation rate is constant or increasing. Inheritance of initiated cells appears to play a minor role. 相似文献
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We are generally concerned with the possible lists of multiplicities for the eigenvalues of a real symmetric matrix with a given graph. Many restrictions are known, but it is often problematic to construct a matrix with desired multiplicities, even if a matrix with such multiplicities exists. Here, we develop a technique for construction using the implicit function theorem in a certain way. We show that the technique works for a large variety of trees, give examples and determine all possible multiplicities for a large class of trees for which this was not previously known. 相似文献
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Petr Knobloch 《Numerical Functional Analysis & Optimization》2013,34(2):161-187
ABSTRACT If finite element spaces for the velocity and pressure do not satisfy the Babu?ka-Brezzi condition, a stable conforming discretization of the Stokes or Navier-Stokes equations can be obtained by enriching the velocity space by suitable functions. Writing any function from the enriched space as a sum of a function from the original space and a function from the supplementary space, the discretization will contain a number of additional terms compared with a conforming discretization for the original pair of spaces. We show that not all these terms are necessary for the solvability of the discrete problem and for optimal convergence properties of the discrete solutions, which is useful for saving computer memory and for establishing a connection to stabilized methods. 相似文献
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Shih-sen Chang H.W. Joseph Lee 《Nonlinear Analysis: Theory, Methods & Applications》2010,73(7):2260-6497
The purpose of this paper is to prove by using a new hybrid method a strong convergence theorem for finding a common element of the set of solutions for a generalized equilibrium problem, the set of solutions for a variational inequality problem and the set of common fixed points for a pair of relatively nonexpansive mappings in a Banach space. As applications, we utilize our results to obtain some new results for finding a solution of an equilibrium problem, a fixed point problem and a common zero-point problem for maximal monotone mappings in Banach spaces. 相似文献
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This paper studies the synthesis of controllers for discrete-time, continuous state stochastic systems subject to omega-regular specifications using finite-state abstractions. Omega-regular properties allow specifying complex behaviors and encompass, for example, linear temporal logic. First, we present a synthesis algorithm for minimizing or maximizing the probability that a discrete-time switched stochastic system with a finite number of modes satisfies an omega-regular property. Our approach relies on a finite-state abstraction of the underlying dynamics in the form of a Bounded-parameter Markov Decision Process arising from a finite partition of the system’s domain. Such Markovian abstractions allow for a range of probabilities of transition between states for each selected action representing a mode of the original system. Our method is built upon an analysis of the Cartesian product between the abstraction and a Deterministic Rabin Automaton encoding the specification of interest or its complement. Specifically, we show that synthesis can be decomposed into a qualitative problem, where the so-called greatest permanent winning components of the product automaton are created, and a quantitative problem, which requires maximizing the probability of reaching this component in the worst-case instantiation of the transition intervals. Additionally, we propose a quantitative metric for measuring the quality of the designed controller with respect to the continuous abstracted states and devise a specification-guided domain partition refinement heuristic with the objective of reaching a user-defined optimality target. Next, we present a method for computing control policies for stochastic systems with a continuous set of available inputs. In this case, the system is assumed to be affine in input and disturbance, and we derive a technique for solving the qualitative and quantitative problems in the resulting finite-state abstractions of such systems. For this, we introduce a new type of abstractions called Controlled Interval-valued Markov Chains. Specifically, we show that the greatest permanent winning component of such abstractions are found by appropriately partitioning the continuous input space in order to generate a bounded-parameter Markov decision process that accounts for all possible qualitative transitions between the finite set of states. Then, the problem of maximizing the probability of reaching these components is cast as a (possibly non-convex) optimization problem over the continuous set of available inputs. A metric of quality for the synthesized controller and a partition refinement scheme are described for this framework as well. Finally, we present a detailed case study. 相似文献
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Walter J. Gutjahr Stefan Katzensteiner Peter Reiter Christian Stummer Michaela Denk 《Central European Journal of Operations Research》2008,16(3):281-306
This paper presents a new model for project portfolio selection, paying specific attention to competence development. The
model seeks to maximize a weighted average of economic gains from projects and strategic gains from the increment of desirable
competencies. As a sub-problem, scheduling and staff assignment for a candidate set of selected projects must also be optimized.
We provide a nonlinear mixed-integer program formulation for the overall problem, and then propose heuristic solution techniques
composed of (1) a greedy heuristic for the scheduling and staff assignment part, and (2) two (alternative) metaheuristics
for the project selection part. The paper outlines experimental results on a real-world application provided by the E-Commerce
Competence Center Austria and, for a slightly simplified instance, presents comparisons with the exact solution computed by
CPLEX. 相似文献