英《糖业文摘》主题词表、作者索引和引用中国期刊的研究

对英国出版的《糖业文摘》（ＳｕｇａｒＩｎｄｕｓｔｒｙＡｂｓｔｒａｃｔｓ）的主题词表、作者索引和引用中国期刊做了初步的研究,介绍了它们的编排特点,提出了我国科技期刊尤其是糖业期刊要创造条件争取进入该刊检索范围的建议     

现代科技时代视角下的国外高层次水利人才培养政策探究

进入科技时代,人才资源成为最重要的资源,获取人才的根本途径在于教育和培养,面对严峻的人才短缺形势,世界各国纷纷采取行动,出台有关政策,争夺和培养复合型高层次人才。虽然发达国家与我国水利高等教育的培养模式不同,但是依然有很多值得借鉴和参考的有效经验,以较为代表的英国、美国及荷兰等国家为例。     

基于IPSec VPN的Intranet组安全模型研究

文章针对实际需求提出了一种在Intranet上可行的VPN简化组安全模型。该集中分层模型特别解决了组管理、策略管理、IKE通信效率和策略冲突问题。     

国内移动终端市场管制政策变迁的原因分析

从1987年到2007年的二十年间,中国移动终端市场管制政策的变革过程就像一个钟摆,经历了市场失灵、政府管制、管制失灵、放松管制、市场再次失灵、期待重新管制的反复轮回,但无论是管制还是放松管制,都是围绕着达到市场资源合理配置而左右摇摆。推动＂钟摆＂周而复始摆动下去的力量,来自于各方利益的博弈。     

Study on the Complexity of the Bullwhip Effect

Recent years have witnessed a rapid growth of interest in the study of the dynamic behavior of replenishment rules of bullwhip effect. We prove that bullwhip effect and butterfly effect share a same the self-oscillation amplifying mechanism that is the ordering decisions the supplier self-oscillation amplify the perturbations brought by the errors in the processing of retailers' demand information. This results as an explicit self-similar structure of the sensitivity of the system to the initial values duty to the nonlinear mechanism. In this paper, the causes process of the bullwhip effect is described as the internal nonlinear mechanism and study on the complexity of bullwhip effect for order-up-to policy under demand signal processing. The methodology is based on fractal and chaotic theory and allows important insights to be gained about the complexity behavior of bullwhip effect.     

Scheduling Rate-Constrained Flows with Dynamic Programming Priority in Time-Triggered Ethernet

Time-triggered (TT), Rate-constrained (RC) and Best-eff ort (BE) traffics are included in Time-triggered ethernet (TTEthernet). For RC messages trans-mission is aff ected by TT messages, traditional schedul-ing policy cannot be well applied in TTEthernet. Dynamic programming priority (DPP) algorithm combines priority policy and dynamic programming algorithm for scheduling RC flows. The time slice for RC flows transmission is got by SMT solver YICES; RC flows are classified to different groups according to the priorities; Higher priority pack-ets in one time slice are scheduled using First input first output (FIFO) policy and lower priority packets are sched-uled by Dynamic programming policy. DPP policy guaran-tees different real-time requirements of heterogeneous RC flows, and make the best of time slice resource in aviation industries. The upper bound End-End of three methods and algorithm feasibility is analyzed. Simulation in avia-tion shows that DPP policy can obtain better real-time performance than other scheduling algorithms.     

从初装费的变化看我国通信网发展的不同阶段

本文介绍我国电话初装费在电话网不同发展阶段的情况。文章认为,我国在解放后很长一段时间内,由于实行低初装费政策,导致企业投资过低,电信网发展缓慢。１９７９年提高初装费标准后,保证了电话网建设的１／３的资源来源。１９７９年提高初装费标准后,保证了电话网建设约／３的资金来源。从现在起,我国将逐渐下调初装费,这将进一步促进电信市场的发展,另一方面,电信网建设的融资方式也将进一步市场化。     

Performance evaluation of an IEEE 802.11g mesh network with multiradio nodes

Wireless mesh networks are usually formed by self‐organized nodes and characterized by high reliability and modularity, low‐cost deployment, and easiness of reconfigurability. In order to improve wireless mesh network performance, several approaches have been recently proposed. Among them, one promising solution seems to be the multiradio interface approach where nodes forming the mesh network are equipped with more than one radio interface. The aim of this paper is to provide an IEEE 802.11 distributed coordination function analytical model to study the behavior of single‐hop multi‐interface mesh networks in which nodes use a uniform random interface selection strategy to identify the radio interface to be used. The accuracy of the proposed analytical approach is validated by comparing analytical predictions with simulation results under actual conditions. Copyright © 2011 John Wiley & Sons, Ltd.     

一种面向Spread组通信的分布式微防火墙体系

论文基于Spread组通信系统的网络结构,提出了一种面向Spread组通信系统的分布式微防火墙体系。体系采用“群组—主机”型的安全策略管理模型,利用组通信的方式发布安全策略。经过实验评估,体系在安全性、时间延迟和扩展性三个方面具有性能优势。     

Technological innovations and 3G mobile phone diffusion: Lessons learned from Japan

Technology and innovation become more important determinants of corporate competitiveness, and the telecommunications sector is no exception. A good example is found in the development of the mobile phones. Technological development, embodied in innovative functions developed from the first (1G) to third generation (3G) systems, has played significantly important roles in the growth and upheavals of the Japanese mobile phone market. In addition, development in contents, value-added services which are supplied by related firms formed in the vertical structure, charging systems, handset development; all these have made this small gadget an increasingly important part of daily life.