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1.
主要得到了一类由概率分布生成的新度量.以信息理论中的重要概念-相对熵为基础,对前人文章中的重要结论进行推广,通过利用改进的初等方法在离散的可测空间中得到了这类新度量,并且证明了得到的新度量成立的充要条件.由此再将这类新度量推广到连续的可测空间中,得到了同样的结果.最后讨论了新度量的最值问题.  相似文献   

2.
In this paper, a new gradient-related algorithm for solving large-scale unconstrained optimization problems is proposed. The new algorithm is a kind of line search method. The basic idea is to choose a combination of the current gradient and some previous search directions as a new search direction and to find a step-size by using various inexact line searches. Using more information at the current iterative step may improve the performance of the algorithm. This motivates us to find some new gradient algorithms which may be more effective than standard conjugate gradient methods. Uniformly gradient-related conception is useful and it can be used to analyze global convergence of the new algorithm. The global convergence and linear convergence rate of the new algorithm are investigated under diverse weak conditions. Numerical experiments show that the new algorithm seems to converge more stably and is superior to other similar methods in many situations.  相似文献   

3.
易文  徐渝  陈志刚 《运筹与管理》2007,16(6):133-136
技术的动态发展和企业间的竞争对企业新产品策略有很大影响,直接决定新产品的引进周期。本文在产业技术动态变化的随机环境下构建随机动态规划模型,关注产业技术进步、投资成本和产品市场竞争等影响因素,探讨企业进行新产品引进的周期选择,对新产品引进的周期和质量决策进行方法设计和应用举例。利用随机动态规划模型得出新产品引进的最优时间周期,用算例分析技术进步和产品研发成本对企业引进周期策略的影响,采取策略迭代的方法进行求解,发现技术进步较快时企业的新产品引进步伐也较快,研发成本的提高使企业的新产品引入步伐降低。  相似文献   

4.
New product development involves several critical decisions. A key decision making area in new product development is the evaluation of the viability and the market potentials of a new product. In the absence of any relevant historical data, companies ask the potential buyers of their products about their intentions to buy those products when assessing their viability. Despite the popularity of the use of behavioral intentions in predicting the market acceptance of new product ideas, both survey and empirical studies suggest that the accuracy of such predictions is usually very low. Although earlier case-based studies suggest that a number of factors can affect the quality of new product decisions, it is still empirically unclear how product knowledge and the type of new products might impact the predictive accuracy of intentions-based new product forecasting. This study utilized a longitudinal research design and empirically tested the hypotheses across two new products. The study first collected purchase intentions data about the new products. Second, it collected subsequent actual purchase data about the new products. The results of series of hierarchical regression analyses comparing the initial purchase intentions and subsequent actual behaviors showed that while product knowledge is positively related to the predictive accuracy and consistency of intentions-based new product forecasting, product type is negatively related to them.  相似文献   

5.
本首先用拟阵语言将图论的新概念定义成了拟阵的新概念,然后用拟阵语言将Goddyn和Heuevl所得的图论上的新结果平移成了拟阵的新结果,最后用拟阵的方法对它们给出了新的证明。  相似文献   

6.
This study considers supply chain network configuration in an innovative environment while the new product development (NPD) will affect the supply chain configuration (SCC). The time of new product introduction has a significant effect on the market performance while it has an effect on the supply chain configuration. Supplier integration into the new product introduction is the key parameter for successfully new product introduction, which may contribute to supply chain reconfiguration. Consequently By considering the new product development concept, we may face with dynamic supply chain configuration during a planning horizontal time. In this study, a new model is presented to consider the dynamic configuration of a supply chain by developing new products. In the proposed model, the dynamic configuration of a supply chain and the new product launching time is optimized simultaneously. The proposed model considers production, sales and transportation planning for the entire supply chain in order to achieve an integrative and efficient supply as well. Then some numerical analyses have been done to show the applicability of the proposed model. The results show that the new product development has a significant effect on the configuration of supply chain.  相似文献   

7.
When both Hamiltonian operators of a bi-Hamiltonian system are pure differential operators, we show that the generalized Kupershmidt deformation (GKD) developed from the Kupershmidt deformation in [10] offers an useful way to construct new integrable system starting from the bi-Hamiltonian system. We construct some new integrable systems by means of the generalized Kupershmidt deformation in the cases of Harry Dym hierarchy, classical Boussinesq hierarchy and coupled KdV hierarchy. We show that the GKD of Harry Dym equation, GKD of classical Boussinesq equation and GKD of coupled KdV equation are equivalent to the new integrable Rosochatius deformations of these soliton equations with self-consistent sources. We present the Lax pair for these new systems. Therefore the generalized Kupershmidt deformation provides a new way to construct new integrable systems from bi-Hamiltonian systems and also offers a new approach to obtain the Rosochatius deformation of soliton equation with self-consistent sources.  相似文献   

8.
概率统计课程中拓广引申式教学法探索   总被引:2,自引:0,他引:2  
概率论和数理统计研究的是随机现象,有许多本学科独有的思维方式和解题模式.学生初学时会面临全新的困难.如何让学生较快地适应本课程的学习?如何引导学生主动地发现问题和探索问题?着重介绍了作者从自己的教学实践中总结出的一套行之有效的方法——拓广引申式教学法.  相似文献   

9.
Extreme Networks     
This paper is supposed to be a review on the new branch of mathematics – extreme networks theory that appeared at the crossroad of differential geometry, variational calculus and discrete mathematics. One of the starting points of the theory is the geometrical approach to the Steiner problem. The authors have selected the most impressive results of the theory demonstrating a new approach, new effects, and new constructions appearing in this context. One of the main aims of the paper is to attract the attention of the specialist from similar fields to this new and rapidly developing theory.  相似文献   

10.
In this paper, a new smoothing Newton method is proposed for solving constrained nonlinear equations. We first transform the constrained nonlinear equations to a system of semismooth equations by using the so-called absolute value function of the slack variables, and then present a new smoothing Newton method for solving the semismooth equations by constructing a new smoothing approximation function. This new method is globally and quadratically convergent. It needs to solve only one system of unconstrained equations and to perform one line search at each iteration. Numerical results show that the new algorithm works quite well.  相似文献   

11.
杜子平  孙瑞泽 《运筹与管理》2022,31(12):157-164
将我国新能源、化石能源和高科技产业纳入同一分析框架,采用因果关系检验、时变copula模型、滚动窗口R藤copula模型研究了三者股价动态相依结构,结果表明:新能源与高科技产业的联动性超过了能源产业内部的联动性,在投资者视角中新能源产业具备较强的高科技属性;新能源与高科技产业的联动性呈下降趋势;新能源与高科技产业的尾部相关系数波动较大,新能源产业的高科技属性对扶持政策的变动较为敏感;新能源产业对高科技产业有长期、稳定的引领作用,而高科技产业仅在特定时期是新能源产业的格兰杰原因,这对“新能源产业的兴衰很大程度依赖于特定科技的发展”这一传统观点提出了质疑。  相似文献   

12.
A new technique of integral representations in Cn, which is different from the well-known Henkin technique, is given. By means of this new technique, a new integral formula for smooth functions and a new integral representation of solutions of the -equations on strictly pseudoconvex domains in Cn are obtained. These new formulas are simpler than the classical ones, especially the solutions of the -equations admit simple uniform estimates. Moreover, this new technique can be further applied to arbitrary bounded domains in Cn so that all corresponding formulas are simplified.  相似文献   

13.
王珏钰  顾超  朱德通 《数学学报》1936,63(6):601-620
本文给出了一种新的多维滤子算法结合非单调信赖域策略解线性约束优化.目标函数及其投影梯度的分量组成了新的多维滤子,并且与信赖域半径有关.当信赖域半径充分小时,新的滤子能接受试探点,避免算法无限循环.非单调信赖域策略保证了新算法的整体收敛性.目前为止,多维滤子算法局部收敛性分析仍然没有解决,在合理假设下,我们分析了新算法的局部超线性收敛性.数值结果验证了算法的有效性.  相似文献   

14.
Quasi-subfield polynomials were introduced by Huang et al. together with a new algorithm to solve the Elliptic Curve Discrete Logarithm Problem (ECDLP) over finite fields of small characteristic. In this paper we provide both new quasi-subfield polynomial families and a new theorem limiting their existence. Our results do not allow to derive any speedup for the new ECDLP algorithm compared to previous approaches.  相似文献   

15.
基于g函数的多元copula的构造   总被引:1,自引:0,他引:1  
针对目前多元copula的构造方法存在的局限性,提出了构造多元copula的新方法.本文首先定义的一类新的函数-g函数,基于g函数建立了2-copula的构造方法,并讨论了该方法的存在性与唯一性问题,然后将2-copula的构造方法直接扩展到n-copula构造的情形.最后给出了g函数的一种寻求方法,从而说明此copula构造方法的可行性.  相似文献   

16.
秦晓伟  刘新国  赵娜 《计算数学》2011,33(4):345-356
对求解极大相关问题的P-SOR方法的收敛性做了进一步研究.得到了一些新的收敛条件.为了提高收敛到全局最大解的可能性,提出了一种新的初始向量选择策略.给出了P-SOR算法的对称形式(P-SSOR).还给出了一种算法精化策略.最后,用数值例子说明新方法的有效性.  相似文献   

17.
青兰  郝晓玲  孙炯 《数学学报》2018,61(2):301-308
本文利用新的方法给出了4阶正则微分算子耦合自共轭边界条件的基本标准型,新标准型中的4个分块小矩阵为对称矩阵,且其行列式的模为1.这与2阶微分算子耦合边界条件的标准型极为类似,这为给出一般的高阶微分算子自共轭边界条件标准型提供了新的思路.  相似文献   

18.
某新型装备维修策略的研究   总被引:4,自引:0,他引:4  
本文对如何借助于专家的知识、经验,科学、合理地制定某新型武器装备的维修策略进行了研究、探讨,提出了具有军事意义、又具有经济价值的新方法。为该新型装备的贮存、管理提供了决策依据,同时也为其它新型装备维修策略的制定提供了思路。  相似文献   

19.
We present a new parallel algorithm for time-periodic problems by combining the waveform relaxation method and the parareal algorithm, which performs the parallelism both in sub-systems and in time. In the new algorithm, the waveform relaxation propagator is chosen as a new fine propagator instead of the classical fine propagator. And because of the characteristic of time-periodic problems, the new parareal waveform relaxation algorithm needs to solve a periodic coarse problem at the coarse level in each iteration. The new algorithm is proved to converge linearly at most. Then the theoretic parallel efficiency of the new algorithm is also considered. Numerical experiments confirm our analysis finally.  相似文献   

20.
We describe a new family of discrete spaces suitable for use with mixed methods on certain quadrilateral and hexahedral meshes. The new spaces are natural in the sense of differential geometry, so all the usual mixed method theory, including the hybrid formulation, carries over to these new elements with proofs unchanged. Because transforming general quadrilaterals into squares introduces nonlinearity and because mixed methods involve the divergence operator, the new spaces are more complicated than either the corresponding Raviart-Thomas spaces for rectangles or corresponding finite element spaces for quadrilaterals. The new spaces are also limited to meshes obtained from a rectangular mesh through the application of a single global bilinear transformation. Despite this limitation, the new elements may be useful in certain topologically regular problems, where initially rectangular grids are deformed to match features of the physical region. They also illustrate the difficulties introduced into the theory of mixed methods by nonlinear transformations.  相似文献   

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