电信需要重组,更需要新思维

上世纪90年代以来,随着通信技术、计算机技术、光电子技术等的飞速发展,尤其是第二代移动通信技术和宽带通信技术的大发展,电信产业的内涵和实质以及存在形式都发生了广泛而深刻的变化.在经济全球化和信息化迅猛发展的今天,电信产业实质上已经完全转变为综合信息服务产业.如今,电信业的自然垄断色彩越来越少,而竞争性特点日益突出.从产业发展周期来看,电信业目前已经进入成熟期,差异化竞争正成为主流竞争形式,市场竞争程度特别是产业外部的竞争压力正在不断增强.     

Interactional models for adults of two populations with maturation delays

This paper is concerned with interactional models for adults of two species delayed by their mature periods. The existence and local stability of equilibria are discussed thoroughly for competitive systems, cooperative systems and predator-prey systems, respectively. For systems with interaction of competition and cooperation, it is found that the two populations are uniformly persistent if the positive equilibrium is stable. For predator-prey interaction, however, some further conditions are needed to guarantee the persistence of the systems.     

Mark Levinson历史名器大盘点

在Mark Levinson品牌近40年的历史中,曾经推出过众多在Hi—End音响史上产生过重大影响的经典名器,从创业早期的JC和LN字头产品,到成熟期的ML系列,     

屹立潮头 紧跟产业市场周期

当前PCB行业已经处于市场成熟期,企业在培育“金牛”业务的同时发展新的“种子”。PCB企业需要将重点转向配合和发展增值产品,以发挥产业拉动的最大效能。