5G移动通信发展趋势与若干关键技术

第5代移动通信系统(5G)是面向2020年之后的新一代移动通信系统,其技术发展尚处于探索阶段.结合国内外移动通信发展的最新趋势,本文对5G移动通信发展的基本需求、技术特点与可能发展途径进行了展望,并分无线传输和无线网络两个部分,重点论述了富有发展前景的7项5G移动通信关键技术,包括大规模天线阵列、基于滤波器组的多载波技术、全双工复用、超密集网络、自组织网络、软件定义网络及内容分发网络.本文还概括性地介绍了国内5G移动通信的相关研发活动及其近期发展目标.     

Australian species of Sinella (Coecobrya) Yosii, 1956 (Collembola: Entomobryidae)

The Australian members of the subgenus, Sinella (Coecobrya) Yosii, are revised. A new species from Western Australia, Queensland, and the Northern Territory, Sinella (Coecobrya) tropicalis sp. nov., is described, Sinella (Coecobrya) tenebricosa Folsom, 1902 is recorded from Australia for the first time, and new records of Sinella (Coecobrya) communis Chen and Christiansen, 1997 Chen, J‐X. and Christiansen, K. A. 1997. Subgenus Coecobrya of the genus Sinella (Collembola: Entomobryidae) with special reference to the species of China.. Annals of the American Society of Entomology, 90: 1–19.  [Google Scholar] are documented. Sinella (Coecobrya) caeca Schött, 1896 is considered a dubious record from Australia. A key is provided to the three known Australian species and a summary given of all dorsal and lateral chaetal patterns found on the fourth abdominal segment of subgenera Sinella Brook, 1882 Brook, G. 1882. On a new genus of Collembola (Sinella) allied to Degeeria Nicolet.. Journal of the Linnean Society of London (Zoology), 16: 541–545.  [Google Scholar] and Coecobrya Yosii, 1956 Yosii, R. 1956. Hohlencollembolen Japans II.. Japanese Journal of Zoology, 11(5): 609–627.  [Google Scholar]. The biogeography of the subgenus is described.     

A revision of Monocotyle Taschenberg, 1878 (Monogenea: Monocotylidae) with descriptions of three new species from Australia

Monocotyle is revised and three new species are proposed. Monocotyle corali sp. nov. is described from the gills of the cowtail ray, Pastinachus sephen (Forsskål) (Dasyatididae), and is distinguished from other members of Monocotyle by the large hamuli with a distinct tail on the guard and by the male copulatory organ with three loops and a wing-like accessory piece at the distal end. Monocotyle jordani sp. nov. from the gills of the southern eagle ray, Myliobatis australis Macleay (Myliobatididae), is differentiated by the male copulatory organ with a large, unique accessory piece. Monocotyle youngi sp. nov., from the gills of Himantura fai Jordan and Seale (Dasyatididae), has marginal haptoral papillae armed with 12 to 15 sclerites, a male copulatory organ with 20 loops and a unique accessory piece at the distal end. Monocotyle trygoni (Venkatanarsaiah and Kulkarni, 1980) Timofeeva, 1985 is synonymized with M. spirophallus Tripathi, 1959 and M. spirophallus is redescribed fully. There are now 16 valid species of Monocotyle and a key to species is presented. Additional data and illustrations of important taxonomic characters are provided. The developmental sequence of the male copulatory organ of M. spiremae Measures, Beverley-Burton and Williams, 1990 from juvenile to adult is described. The anterior glands and the type of secretion they contain are also documented for several species of Monocotyle.     

高校大型仪器设备关口管理的探索

结合工作实际,在高校大型仪器设备的投资预测、决策中的立项论证、审核招标、采购实施几个环节方面进行探讨,并在此基础上提出大型仪器设备关口管理的基本思路,以期规范购置的前期管理程序,避免科技资源浪费,更合理使用资金和符合建设节约型社会的需要.     

依托地铁发展整合广州站域公共空间资源

广州地铁的网络化发展正在逐步走向成熟,城市公共空间在"以公交为导向"的城市规划理念(TOD)下,依托地铁发展,有效地整合功能和建立有地域性特征的发展模式是其中的关键环节.文中通过对现状和问题的分析、比较研究,用系统科学的方法,提出以地铁车站为核心、步行系统为联系纽带,形成网络化的站域公共空间体系.     

在Java中进行数字签名的一种实现方法

随着Internet和电子商务的快速发展,对网络信息安全提出了更高的要求,而数字签名技术在保证数据的完整性、私有性和不可低赖性方面起着极为重要的作用。介绍了公开密钥加密体制及数字签名技术的实现过程,通过引入第三方控件并结合Java安全API数字签名方法,给出了数字签名技术在Java中的一种实现方法。     

公共图书馆讲座与未成年人思想道德教育

阐述了公共图书馆讲座对于未成年人思想道德教育的重要性和必要性,分析了我国未成年人思想道德教育的现状及存在的问题,并对公共图书馆讲座如何为未成年人提供思想道德教育的具体方法进行了探讨。     

浅谈公共图书馆的读者教育工作

阐述了公共图书馆读者教育的必要性及其意义,指出应从发展公共图书馆事业的战略高度重视公共图书馆的读者教育,并提出了公共图书馆开展读者教育的主要方式和途径。     

公共图书馆应积极为建设学习型社区服务

论述了构建学习型社区的重要性,分析了学习型社区现状及存在的问题,就图书馆应如何积极参与学习型社区建设,更好地为读者服务展开了讨论。