关于运用“地面业务典型发射电台通知单”开展频率指配国际登记的思考

本文在研究相关管理规定和《无线电规则》具体条款的基础上,探索了向国际电信联盟登记地面业务频率指配的不同方式,特别是通过运用通知单T14表格登记典型发射电台的特性数据,可以使频率指配国际登记工作效率大幅提高。

广播频率调度业务的数学建模

本文介绍了广播频率调度业务的形式和工作流程。运用集合、函数等数学方法,深入分析了调度执行系统广播频率调度业务的数学特性,通过建立数学模型,得出了广播频率调度业务的一般特点,为该业务的程序开发提供数学基础。

面向工作流管理系统的动态构件预取方法

基于软构件和工作流技术的ESA(Enterprise Software&Application)系统运行效率不仅取决于功能性的因素,还受到非功能性因素的影响,而且常常被忽视.把业务频率这一重要的非功能性因素融入到ESA系统中,同时结合构件的使用频度和构件出现的间隔这两个因素,提出构件预取模型,包括相对依赖强度和绝对依赖强度两个计算模型.前者体现了构件使用频度,后者体现了构件出现的间隔.业务频率则通过工作流日志融入两个模型中,以此提高构件实例化时缓冲的命中率,缩短应用服务器对用户访问的响应时间.最后的实验结果表明,该方法具有工作流的优势,能为构件缓冲提供更加准确的预测.

面向工作流管理系统的多粒度构件组织技术

针对影响软构件的ESA(enterprise software and application)系统运行效率的非功能性因素常常被忽视的现状,为提高构件复用效率,提出了一种面向流程的多粒度构件组织方法。基于工作流技术,通过分析业务过程中业务频率的变化对构件执行负载的影响,以及构件粒度和构件复用效率之间的关系,把业务频率这一非功能性因素反映到构件组织方式中,提出了多粒度的构件库组织形式,并给出了相应的算法。实验及构件复用效率分析表明,多粒度构件组织方法完全能够使构件复用效率随业务频率的变化保持最高,进而使ESA系统运行效率也保持最高。

基于服务工作流的服务动态预取模型

为了提高服务工作流的整体效率,通过工作流日志挖掘出业务的主要影响因素,再结合服务调用时的主要效率瓶颈,提出服务预取模型。通过该模型可计算出待预取的服务,以此提高服务实例化时缓冲的命中率,缩短用户的访问延迟。实验结果表明,该方法拥有服务工作流的引导优势,能为服务缓冲提供更加精确的预测。

基于可变粒度的服务工作流系统服务质量可控性研究

通过分析业务频率对服务质量(quality of service,QoS)的影响,以及服务粒度和系统性能之间的关系,提出一种服务质量可控的、多粒度的服务动态组合方法,并给出了相应的算法。该方法在候选服务集少的情况下,根据业务的发生频率,可对系统结构做自适应的调整,进而把系统的整体服务质量控制在一个最优的水平。仿真实验结果表明该方法完全可以持续改善服务工作流系统的运行效率。

The Community Radio in Thailand： 2012 Onwards

Radio broadcasting services in Thailand are in transition and face an uncertain future. This situation has arisen from enforcement of the 2010 Frequency Allocation and Telecommunications Business Act and the establishment of the National Broadcasting and Telecommunications Commission （NBTC） as a single, combined regulatory body for broadcasting and telecommunications. The Act brings in significant changes through ＂liberalization＂ in telecoms and broadcasting markets. Key events expected in the future, such as the implementation of AEC in 2015 and the transformation from analog to digital systems will have significant detrimental impact on the Thai broadcasting industry. These changes will affect 524 AM and FM radio stations and around 7,000 community radio operations. This paper gives a picture of radio broadcasting industry, especially of community radio stations, their history, present and future. It also argues that the survival of radio stations in Thailand after 2015 will depend on （l） its social, institutional, financial, and technical abilities; and （2） the ability of NBTC to adopt and enforce policy and regulation for promoting free and fair competition.

Bit Loading Algorithm of VSF-OFCDM wireless communication

In VSF-OFCDM wireless communication, wireless channel is divided into component channels with the same frequency space according to the frequency, and the carriers on component channels are mutually orthogonal. When there are enough subcarriers, the bandwidth efficiency of the system is close to nyquist limit, which can ensure the utilization ratio of system frequency. Therefore, under the premise of ensuring orthogonal division of channels, the channels received a secondary division according to data rate requirements and power limit of business to make the frequency resource fully used and makes the total power minimal, which realizes the optimal distribution of wireless-communication system resources. The secondary division is represented by bit loading algorithm the best bit number of subcarrier allocation in symbol period. For the characteristics of wide-band multi-media services and granular division of VSF-OFCDM wireless communication, the subject proposes the idea of business-oriented subcarrier allocation, which means that the subcarriers are divided in symbol period with the business as the dominant. Based on the idea, the paper designs service-oriented bit loading algorithm of subcarrier, byte and power combined with distribution based on channel detection, and makes verification and performance analysis on the algorithm.

Multi-service small-cell cloud wired/wireless access network based on tunable optical frequency comb

In this paper,we demonstrate a novel multi-service wired/wireless integrated access architecture of cloud radio access network(C-RAN) based on radio-over-fiber passive optical network(RoF-PON) system,which utilizes scalable multiple-frequency millimeter-wave(MF-MMW) generation based on tunable optical frequency comb(TOFC).In the baseband unit(BBU) pool,the generated optical comb lines are modulated into wired,RoF and WiFi/WiMAX signals,respectively.The multi-frequency RoF signals are generated by beating the optical comb line pairs in the small cell.The WiFi/WiMAX signals are demodulated after passing through the band pass filter(BPF) and band stop filter(BSF),respectively,whereas the wired signal can be received directly.The feasibility and scalability of the proposed multi-service wired/wireless integrated C-RAN are confirmed by the simulations.