The importance of consumer multihoming (joint purchases) for market performance: Mergers and entry in media markets

Consumer “multihoming” (watching two TV channels, or buying two news magazines) has surprisingly important effects on market equilibrium and performance in (two‐sided) media markets. We show this by introducing consumer multihoming and advertising finance into the classic circle model of product differentiation. When consumers multihome (attend more than one platform), media platforms can charge only incremental value prices to advertisers. Entry or merger leaves consumer prices unchanged under consumer multihoming, but leaves advertiser prices unchanged under single‐homing: Multihoming flips the side of the market on which platforms compete. In contrast to standard circle results, equilibrium product variety can be insufficient under multihoming.     

Periodic strategies in optimal execution with multiplicative price impact

We study the optimal execution problem with multiplicative price impact in algorithmic trading, when an agent holds an initial position of shares of a financial asset. The interselling decision times are modeled by the arrival times of a Poisson process. The criterion to be optimized consists in maximizing the expected net present value of the gains of the agent, and it is proved that an optimal strategy has a barrier form, depending only on the number of shares left and the level of the asset price.     

张峰水库溢洪道体型优化设计

本文对已设计的张峰水库溢洪道进行了模型试验,根据对试验结果分析,认为原方案设计存在一些问题,并针对问题进行了优化设计。通过对修改方案模型试验结果分析,得出修改方案改进了原方案中存在的不足,优化合理,是可以采用的。     

水资源系统分析法在水资源优化配置中的应用

探讨了水资源系统分析法的步骤和数学模型,并以线性规划模型为例建立了水资源优化配置的数学模型,对水资源优化配置提供了一定的依据。     

对群众体育锻炼中，如何合理安排运动量的探讨

本文在体育锻炼能够增强体质，提高健康水平的生物学基础上和群众体育锻炼与专业训练的区别上，提出群众体育锻炼中如何合理安排运动量。     

Optimal Emissions Taxation under Imperfect Competition in a Durable Good Industry

This paper investigates optimal emissions taxation under imperfect competition in a durable good industry where products are sold (instead of rented). As a benchmark, attention is paid to the special case of monopoly with exogenously given product durability. In line with previous literature, the optimal emission tax in this benchmark model falls short of marginal damage (underinternalization). Extending the benchmark model either to the case of an oligopolistic market structure and/or to the case of endogenous product durability then provides two cases in which the optimal emission tax overinternalizes marginal damage.     

南水北调西线工程可调水量分析

在受水区缺水形势严峻的情况下，引水工程可调水量的确定主要与三个因素有关：一是引水河流及引水坝址径流量；二是坝址上下游用水要求；三是引水水库工程规模。在考虑各种因素影响后，提出各引水坝址可调水量占坝比径流量的比例在70％左右比较合适，按现阶段推荐的两种方案，可调水量可达160亿－170亿m^3.     

小浪底水库运用初期非汛期调度方式的分析

应用水量调度决策支持系统 ,研究了小浪底水库考虑多个兴利目标的非汛期优化运用方案 ,对运用方案分析提出了水库优化运用区间 ,采用数理统计方法探讨了水库非汛期的线性调度函数 ,取得了初步成果可供水量调度部门参考使用     

Fuzzy Multiobjective and Linear Programming Based Management Models for Optimal Land-Water-Crop System Planning

In this article, linear programming and fuzzy optimization models are developed for planning and management of available land-water-crop system of Mahanadi-Kathajodi delta in eastern India. The models are used to optimize the economic return, production and labour utilization, and to search the related cropping patterns and intensities with specified land, water, fertilizer and labour availability, and water use pattern constraints. Due to extreme backwardness of the study area, it has been decided to keep all the three objectives of the linear programming models at the same priority level to obtain the compromised solution in a fuzzy environment that incorporates the imprecision in fuzzy goals and fuzzy constraints. These non-structural models facilitate the conjunctive use of available surface water and groundwater resources. A comparative evaluation along with the benefit-cost ratios of the existing and proposed farming systems is also presented.