Cost-Effective Migration from Sub-Lambda to Wavelength-Based Metro Networks

This article will discuss the importance of hybrid coexistence of sub-lambda grooming with wavelength-based services for driving down costs and maximizing the use of metro bandwidth, as well as enabling next-generation lambda-based services. The article will also address migration to all optical metro networks.     

Cost-Effective Migration from Sub-Lambda to Wavelength-Based Metro Networks

This article will discuss the importance of hybrid coexistence of sub-lambda grooming with wavelength-based services for driving down costs and maximizing the use of metro bandwidth, as well as enabling next-generation lambda-based services. The article will also address migration to all optical metro networks.     

碳交易机制下考虑制造商竞争的供应链协调研究

在碳交易机制背景下考虑普通制造商和低碳制造商存在竞争的情形,分别构建集中和分散模式下的供应链决策模型并对减排率以及产品销售价格进行求解。针对分散决策造成的供应链利润损失情况,采用Shapley值法对供应链进行协调,并给出契约协调机制。最后通过算例分析了Shapley值法的有效性,并对碳交易价格和消费者价格敏感性进行灵敏度分析。研究表明:Shapley值法的引入提高了供应链成员以及供应链的总利润,实现了供应链协调;碳交易机制的实施减少了碳排放总量,但较高的碳交易价格会降低供应链利润;消费者价格敏感性的增加使得普通制造商、低碳制造商、零售商以及供应链整体利润均降低。     

消费者偏好下的两在位制造商阻止策略选择研究

讨论生产高质量产品和生产低质量产品的两个在位制造商阻止生产中等质量产品的潜在制造商进入市场策略,考虑消费者产品质量偏好,分别建立了两个在位制造商采取不改变定价策略、采取联合定价阻止策略以及采取联合产量阻止策略模型,分析不同阻止策略对产品价格、在位制造商利润和潜在制造商进入成本的影响.数值分析结果研究表明,当进入成本高于某个阈值时,在位制造商不用采取任何阻止策略潜在制造商都不会进入市场.当进入成本适中时,相比其他两种阻止策略,两个在位制造商采取联合产量阻止策略会使潜在制造商的最低进入成本最大,这种策略下生产高质量产品的在位制造商利润最大,而生产低质量产品的在位制造商的利润最小.     

A robust algorithm for quadratic optimization under quadratic constraints

Most existing methods of quadratically constrained quadratic optimization actually solve a refined linear or convex relaxation of the original problem. It turned out, however, that such an approach may sometimes provide an infeasible solution which cannot be accepted as an approximate optimal solution in any reasonable sense. To overcome these limitations a new approach is proposed that guarantees a more appropriate approximate optimal solution which is also stable under small perturbations of the constraints.