光纤和光缆的偏振模色散系数研究

综述了偏振模色散的概念、偏振模色散对光传输系统的影响、系统对单模光纤偏振模色散系数的要求,以及获得小的偏振模色散光纤和光缆的方法.     

飞机系统内的干扰源及干扰防止方法

现代飞机电子设备越来越多,而一个良好的电磁环境对于飞机系统正常工作有着重要的作用.该文通过对飞机上干扰源的认识、分析及干扰的防止方法,对从事飞机电气设计的工程技术人员起到一些借鉴作用.     

泰州大桥主缆干燥空气除湿法泄漏率的测试实验研究

通过对泰州长江公路大桥主缆送气量和送气压力的数据分析,给出了维护阶段悬索桥主缆漏气量和送气压力之间的半经验公式,对于后期悬索桥在设计使用过程中选择正确的送气压力和送气量有一定的借鉴意义。     

Alternating-current losses in two-layer superconducting cables consisting of second-generation superconductors coated by U-shaped ferromagnetic materials

Alternating-current losses in a two-layer superconducting cable, each layer being composed of 15 closely-spaced rectangular wires made up of second-generation superconductors when the ends of wires are coated by either a non-magnetic or strong ferromagnetic material having a U profile is numerically investigated. Computations are carried out through the finite-element method. The alternating-current losses do not increase significantly if the relative permeability of the coating is increased three orders of magnitude, provided that the current amplitude is less than half of the critical current in a superconducting wire. However, the losses are much higher for ferromagnetic coating if the amplitude of the applied current oscillating at 50 Hz is close to the critical current. The ferromagnetic coating is seen to accumulate the magnetic field lines normally on its surfaces, while the field lines are parallel to the long axes of the wires, leading to more significant flux penetration in the coated regions. This facilitates a uniform low-loss current flow in the uncoated regions of the wires. In contrast, coating with a non-magnetic material gives rise to a considerably smaller current flow in the uncoated regions, whereas the low-loss flow is maintained in the coated regions. Moreover, the current flows in opposite directions in the coated and uncoated regions, where the direction in each region is converse for the two materials.     

一种单纯形遗传算法及其应用

本文深入分析了智能天线应用中广播波束成形权值反向求解的工程优化问题,引入单纯形算法对传统遗传算法进行改进并提出了一种新的单纯形遗传算法。通过具体应用验证,实现了较好自动求解权值的目的。同时,本算法也可在其他网络规划和网络优化等寻优问题中参考使用。     

从广播网络化到网络化广播的发展探讨

本文主要针对广播的发展状况,探讨广播从广播网络化到网络化广播的一些发展变化.主要介绍了如何会产生这些变化,以及网络化广播的特点和优势.使人们认识到网络与广播之间密不可分的关系,以及今后网络化广播发展的方向.     

中波广播发射机功放问题与解决建议研究

调频广播发射技术的核心载体源自广播发射机,其中国内又主要以中波发射机为主.因此,研究中波广播发射机的故障是确保广播发射工作有序开展的先决条件,具有重要的现实意义.本文以国内广播电台应用广泛的DAM-50KW中波广播发射机为例,对维护功放模块的损坏问题和解决检测方法展开分析和总结.     

E-business technologies for xRM: Exploring the readiness of public broadcasters

This paper examines the possibilities of enhancing relationship management between public service broadcasters and their stakeholders by harnessing the potential of newest e-business technologies and concepts, such as: social media, digital and interactive TV, and mobile computing. In order to facilitate adoption of relationship management strategy, a framework for leveraging relationship management is proposed. Evaluation was performed within the e-business system of a public broadcaster. This empirical study explored the readiness and expected benefits of relationship management implementation. The research results have indicated that a public broadcaster could achieve a higher level of social responsibility, improve business sustainability, and empower communication and collaboration with all the stakeholders by using emerging technologies for relationship management activities.     

三网融合给广播电视网络带来的机遇与挑战

阐述了三网融合的起源和意义,介绍了三网融合的路径,分析了三网融合给广播电视网络带来的机遇和挑战,并提出相应策略。     

多路时移电视节目系统

单向数字电视系统业务单一，不能满足人们的需要，时移电视系统应运而生。改变了人们的收视习惯，完善了数字电视的功能。重点介绍库车县广播电视局22路时移电视节目系统的组成，22路时移电视节目的制作及注意事项。