一个数学建模问题的简单解法

银行利率给出了一个简单计算方法 ,这种方法更符合中学生思维的习惯 .     

理论研究电流注入对垂直腔面发射激光器多横模行为的影响

从包含时空变量的速率方程出发,针对弱折射率导引垂直腔面发射激光器(VCSELs),利用空间积分法分析了典型电注入参数对VCSELs多横模行为的影响,在不降低模型准确性的前提下提高了仿真效率。仿真结果表明,注入盘孔径和注入环越小、注入强度越低以及电流扩散越弱时,VCSELs更易实现单横模工作;反之,VCSELs高阶横模开始出现并呈现较强的模式竞争,引发了载流子空间烧孔效应,并导致基模强度降低。进一步得出,在环形注入方式下,高阶模式更容易出现且彼此间的竞争较盘形注入时强。     

Gain competition effect in dual-wavelength dye lasers

In this paper, we present a theoretical model for the gain competition in dual-wavelength dye lasers. For this purpose the rate equations under the steady-state conditions have been used. The degree of the gain competition is shown to depend on the polarization of the two laser beams. The dependence of the gain competition on various working parameters such as pumping power, dye concentration and the reorientation rate of the molecules or solvent viscosity is studied for two different cases of parallel and orthogonal polarizations. The results of our model show dramatically different behaviors in the two proposed cases.     

浙江发展会展旅游的战略构想

通过对浙江会展旅游现状的分析和研究,总结了浙江会展旅游业的现状与优势,指出了面临的问题,进而从政府与会展企业角度提出了发展浙江会展旅游业的对策.     

A note on theβ-measure for digraph competitions

Digraph games are cooperative TU-games associated to digraph competitions: domination structures that can be modeled by directed graphs. Examples come from sports competitions or from simple majority win digraphs corresponding to preference profiles for a group of individuals within the framework of social choice theory. Brink and Gilles (2000) defined theβ-measure of a digraph competition as the Shapley value of the corresponding digraph game. This paper provides a new characterization of theβ-measure.     

工科学校本科生科研训练与实践——以节能减排大赛为例

Scientific research training is an essential part of undergraduate learning, which plays an important role in improving students' knowledge utilization and scientific literacy. Taking the participation process of "Energy conservation and emission reduction competition" as an example, this paper briefly introduces the undergraduate scientific research training of students majoring in polymer materials and engineering from their own perspective, and the way to combine the discipline and school characteristics to reflect the thinking of engineering students in scientific research and practical application.     

A capacity reservation game for suppliers with multiple blocks of capacity

This paper studies a supplier competition model in which a buyer reserves capacity from a number of suppliers that each have multiple blocks of capacity (e.g., production or power plants). The suppliers each submit a bid that specifies a reservation price and an execution price for every block, and the buyer determines what blocks to reserve. This game involves both external competition between suppliers and internal competition between blocks from each supplier. We characterize the properties of pure-strategy Nash equilibria for the game. Such equilibria may not always exist, and we provide the conditions under which they do.     

价格与质量双重竞争下电商平台渠道模式决策研究

近年来传统电商正加速从经销商转变为连接消费者与供应商的在线市场中间商, 电商平台与供应商形成三种渠道结构:经销商模式、混合模式和在线市场模式。本文通过构建Stackelberg博弈模型讨论产品质量与价格双重竞争情境下电商平台与供应商销售合作模式最新选择问题。研究表明,当价格竞争强度适中而佣金比例较大时,混合模式是电商平台最优选择,此时产品质量差异最大;当价格竞争强度较小而佣金比例较大时,在线市场模式则是最优选择;在其他条件下,经销商模式是其最优选择。本文结论对电商平台与供应商合作模式选择、产品质量与定价决策具有参考价值。     

竞争市场下考虑再制造产品售后服务的供应链运营策略

在同时生产新产品和再制造产品的原始制造企业(企业1)与生产具有替代性产品的企业(企业2)构成竞争关系下的供应链系统中,探讨供应链在不同售后服务策略下供应链的运营策略,分析在竞争市场下供应链定价策略和再制造产品的售后服务对定价策略及供应链中各企业利润的影响。揭示再制造产品售后服务对定价策略和供应链各企业最优利润的影响。得到如下主要研究结论:(1)当制造企业为再制造产品提供售后服务时,再制造产品销售量增加,新产品和竞争替代产品销售量降低;有趣的是新产品和再制造产品的市场零售价格同时增加,竞争替代产品的市场零售价格降低。(2)制造企业为再制造产品提供售后服务时的利润总是大于没有售后服务时的利润,且不受单位产品生产成本影响。同时当单位产品生产成本较高时,制造企业为再制造产品提供售后服务策略会带来竞争对手企业利润增加。这些结论对具有再制造产品供应链如何提供再制造产品售后服务具有一定指导作用和管理启示。     

Cooperative Competition Clustering for Gene Selection

Clustering analysis of data from DNA microarray hybridization studies is an essential task for identifying biologically relevant groups of genes. Attribute cluster algorithm (ACA) has provided an attractive way to group and select meaningful genes. However, ACA needs much prior knowledge about the genes to set the number of clusters. In practical applications, if the number of clusters is misspecified, the performance of the ACA will deteriorate rapidly. We propose the Cooperative Competition Cluster Algorithm (CCCA) in this paper. In the algorithm, we assume that both cooperation and competition exist simultaneously between clusters in the process of clustering. By using this principle of Cooperative Competition, the number of clusters can be found in the process of clustering. Experimental results on a synthetic and gene expression data are demonstrated. The results show that CCCA can choose the number of clusters automatically and get excellent performance with respect to other competing methods.