基于Java2的数字签名技术

数字签名是现代互联网中应用十分广泛的一种信息安全技术，用于保证在不安全的公共网络中，信息传输过程中的完整性以及信息发送的不可抵赖性。结合Java2特有的安全体系结构，详细讨论了数字签名的定义、作用和基本原理，并给出了一个Java2中数字签名的具体实例。     

基于Java的电子公文加密传输

如何保证政府电子政务的安全性是实施电子政务必须首先要解决的问题。介绍了信息安全领域中的公开密钥加密体系和数字签名以及Java的安全机制;针对目前办公自动化系统中电子公文传输普遍存在的安全问题,利用Java中的安全软件包实现了对电子公文的数字签名,从而保证了在政府部门内部数据传输的可认证性、完整性和不可抵赖性。     

无线网络融合的安全技术研究

融合多种网络可满足用户长日寸间连接和尽可能获得较高数据传输速率的需要，但融合后的网络也将各种网络的安全缺陷带进融合网络中。这不但给融合网络的运行带进各种原有的安全问题，而且增加了一些新的安全问题。对此，文章提出了基于恢复的多重防护解决方案，并使用公钥加密算法鉴权。使用私钥对通信数据进行加密。该方案可以为系统提供可靠的安全性，并实现用户对服务的不可抵赖性。该方案还处于研究起步阶段，下一步还需要明确各层的正确行为，以及出现多个恶意节点对某个合法节点诬陷时所应采取的行动。     

面向融合的移动通信网络安全关键技术研究

随着我国社会经济和科学技术的快速发展，移动通信网络已经深入到各行各业中，人们对移动通信网络的要求越来越高。在人们的众多要求中，安全方面的需求最为重要。在固定移动融合（Fix Mobile Convergence，FMC）体系的框架下，可以为移动通信网络提供更多的对外接口，使移动通信网络更具开放性，同时原有体系中的不安全因素逐渐暴露出来，成了重要的安全威胁，降低了移动通信网络整体的安全性。在这种情况下，需要注重面向融合的移动通信网络安全关键技术的研究工作，并提出切实可行的方案，这对我国整体的移动通信网络发展具有重要的作用和价值。     

移动通信网络中的安全保密技术

分析了移动通信网络中的不安全因素,重点讨论了移动通信网络中的身份认证和密钥分配,数据加密与完整性检测方案,并对其安全性进行了详细分析.     

基于哈稀链和认证树的组播源认证

结合哈稀链和认证树的优点，文中提出了一个新方案，首先将一个流分成大小相同的块，然后在每个块中构造出一些二叉树，对这些树使用哈稀链。这种方案使用数字签名保证了不可抵赖性，通信开销小，并且可以有效抵御包丢失。     

SIP协议不可抵赖性的设计与实现

伴随着VOIP的广泛使用,SIP协议已受到越来越多人的青睐,但SIP面临的安全威胁以及SIP安全机制的现状又令人不得不警觉.文中针对SIP协议的安全性设计并实现了不可抵赖性的解决方案,对使用SHA-1/MD5的算法在不同的硬件配置下实现不可抵赖性进行了性能分析.通过性能测试,在不同的硬件配置情况下,其速度是随着硬件配置的高低呈正态分布的.在实验室环境下,所提出的SIP不可抵赖性的方案可以很好地运行,并且具有通用性,能够被广泛地采用.     

数字移动通信中的安全问题

本文论述了数字移动通信系统中的几个安全问题：会话的保密性，移动单元与基站之间的相互确认，以及移动单元的难以跟踪性等。并提出了一种新的且适合于移动通信特点的密钥分发方案，以此为基础，可以实现双人通信或电话会议的保密。     

诺基亚西门子通信推出代维服务运营与保证解决方案

在2009年移动通信世界大会上，诺基亚西门子通信推出了代维服务运营与保证解决方案，旨在帮助通信服务提供商（CSP）应对三大挑战：高效管理最终用户的服务运营、保证服务质量、提高最终用户业务收益。该方案可支持CSP监测，报告并分析服务性能与用户体验，提供主动的性能优化服务和系统的故障排除方案；     

适用于数字移动通信系统的用户认证方案

基于Schnorr签名，提出了一种适用于数字移动通信系统的用户身份认证方案。该方案能实现双方相互认证，抵抗各种攻击（包括网内攻击）。在用户端引入预计算，减少了用户端的计算量，满足了移动通信的实时要求。并对该方案的安全性及计算复杂性进行了分析，得出了该方案是一个安全性高，计算复杂性低，符合数字移动通信系统要求的结论。     

《青年与科学》与抗日战争时期的科技传播

《青年与科学》是抗日战争时期在重庆创办的通俗科学刊物,提倡科学研究与普及科学知识为其办刊宗旨。《青年与科学》介绍和传播了基础科技知识、科技新发明和新发现以及科学人物,同时刊登科学评论引导社会舆论。《青年与科学》的传播内容围绕军事和抗战,适应抗战的时代需求,传播内容具有实用性和亲近性的特点。写作上通俗性与科学性相结合。稿件多由专家、学者撰写,具有严谨性和权威性。传播手段上注重与读者进行互动。《青年与科学》在抗日战争的特殊时期传播了科学技术知识,为普及科学知识,唤起民众的科学救国意识做出了积极的贡献。     

策略三十六计和算法三十六计

本着文化自信的精神,深入学习具有三千多年历史的《易经》,挖掘《易经》形象思维的抽象和推理的理念,结合现代计算机学科的发展和作者本身的专业经历,给出了计算机系统设计策略三十六计和算法三十六计的初步成果.本文提出了计算机学科的四个基本对立统一关系,即四个基本科学问题：集分定位、刚柔相摩、供需相应、串并转换.从集分定位出发,在策略三十六计中提出了架构设计十八计,它包括了时空转换和多种计算模式的计策.从刚柔相摩出发,在策略三十六计中提出了系统特性十八计,它包括了八类特性设计的计策,例如,可控性、效率性、安全性、可变性等方面的计策.供需相应和串并转换所涉及的科学问题,主要体现在资源管理和任务调度的算法三十六计中.这些算法计策中包含了计算机学科的经典和热点问题,例如,可计算性、多目标优化、云计算、软件定义系统、大数据思维和人工智能等.策略三十六计和算法三十六计可以为计算机专业人员在学习和系统研发工作中提供思维框架、策略辩证思路和需要的计策及实例,更为重要的是可以进一步理解事物的哲学道理.     

Dynamic defenses in cyber security: Techniques,methods and challenges

Driven by the rapid development of the Internet of Things, cloud computing and other emerging technologies, the connotation of cyberspace is constantly expanding and becoming the fifth dimension of human activities. However, security problems in cyberspace are becoming serious, and traditional defense measures (e.g., firewall, intrusion detection systems, and security audits) often fall into a passive situation of being prone to attacks and difficult to take effect when responding to new types of network attacks with a higher and higher degree of coordination and intelligence. By constructing and implementing the diverse strategy of dynamic transformation, the configuration characteristics of systems are constantly changing, and the probability of vulnerability exposure is increasing. Therefore, the difficulty and cost of attack are increasing, which provides new ideas for reversing the asymmetric situation of defense and attack in cyberspace. Nonetheless, few related works systematically introduce dynamic defense mechanisms for cyber security. The related concepts and development strategies of dynamic defense are rarely analyzed and summarized. To bridge this gap, we conduct a comprehensive and concrete survey of recent research efforts on dynamic defense in cyber security. Specifically, we firstly introduce basic concepts and define dynamic defense in cyber security. Next, we review the architectures, enabling techniques and methods for moving target defense and mimic defense. This is followed by taxonomically summarizing the implementation and evaluation of dynamic defense. Finally, we discuss some open challenges and opportunities for dynamic defense in cyber security.     

智能雷场的无线传感器网络技术研究

智能地雷是现代新概念弹药,其关键技术是声/震传感器阵列探测及组网通信技术。本文根据自动布设的智能地雷系统的作战使用方式,详细描述了智能地雷的工作原理和工作过程,细划地雷系统的组成部分及其功能。并基于无线传感器网络技术(WSN)提出了一种网络化智能雷场系统方案及其无线传感器网络构建、自定位、自组织等关键技术的解决方案,据此可构建地雷场的自组织网络。该方案具有通信定位组网一体化设计,集成度高、工程实现简洁的特点。     

RFID重要物品管控技术研究

在对传统的重要物品管控和引进RFID技术后的重要物品管控存在的问题、难点分析基础上,提出了重要物品管控的区域定位概念和重要物品安全确认方法的一种新的管控技术.文中根据区域定位概念,结合实际场景说明了如何对不同场所进行区域划分,明确阐述了重要物品安全的确认方法.成都三零瑞通移动通信有限公司利用新管控技术研发了重要物品管控系统,文中对管控系统组成、各设备的部署要求和功能进行了详细介绍,并总结出重要物品管控系统的特点.通过管控系统及应用拓展说明新管控技术不仅可切实解决在重要物品管控中存在的问题和难点,还可在其他管控应用中大力推广.     

Metadata Design for Reconfigurable Protocol Stacks in Systems Beyond 3G

Global consensus on the next generation of wireless mobile communications, broadly termed “beyond 3G”, sketches a heterogeneous infrastructure comprising different wireless systems in a complementary manner and vested with reconfiguration capabilities, which support a flexible and dynamic adaptation of the wireless network and its spectrum resources to meet the ever-changing service requirements. For ubiquitous reconfiguration to become a practical capability of mobile communication systems, it is necessary to establish a global architecture for modeling, expressing, and circulating essential metadata related to reconfiguration, including reconfigurable device capabilities and semantic properties of protocol stacks. We outline the relevant standardization initiatives in the mobile domain, summarize existing work in reconfiguration-supporting architectures, and identify key shortcomings that may hinder the advent of ubiquitously reconfigurable systems. Further on, we point out some major limitations of current metadata standards in the mobile domain for the representation of capability information pertaining to reconfigurable protocol stacks. Next, we identify essential metadata classes in support of reconfigurable communication systems, introducing an associated object-oriented UML model. We elaborate on the design rationale of the UML model, presenting and discussing the alternative metadata representation standards and suitable encoding formats. Finally, we demonstrate the suitability of our UML model by applying our reconfiguration-supporting vocabulary in the cases of a standardized protocol stack of 3G mobile devices and stationary 3G cellular network elements. Vangelis Gazis received his B.Sc. and M.Sc. (Communication Networking) degrees from the Department of Informatics & Telecommunications of the University of Athens, Greece, in 1995, and 1998, respectively. He also received an M.B.A. degree from the Athens University of Economics and Business in 2001. Since 1996 until, he has been with the research staff of the Communication Networks Laboratory (CNL) of the University of Athens. He has participated in national and European research projects (MOBIVAS, ANWIRE) of the IST framework programme. He specializes in reconfigurable mobile systems and networks for beyond 3G, metadata and ontology languages, reflective and component middleware, adaptable services and open API frameworks for telecommunications. He is currently a Ph.D. candidate in the Department of Informatics & Telecommunications of the University of Athens. Nancy Alonistioti holds a B.Sc. degree and a Ph.D. degree in informatics and telecommunications from the University of Athens. Presently, she is a senior researcher in the Department of Informatics and Telecommunications of the University of Athens. In the past, she has held a research position with the Institute of Informatics and Telecommunications of NCSR “Demokritos” in the areas of protocol and service design and testing, mobile systems (UMTS), open architectures, and software defined radio systems and networks. Her current research interests are in reconfigurable mobile systems and networks beyond 3G, and adaptable services, pervasive computing and context awareness. She has participated in several national and European R&D projects, and has been the technical manager of the IST-MOBIVAS and IST-ANWIRE projects, which have had a focus on reconfigurable mobile systems, networks an respective service provision. She is currently a member of the management team and workpackage leader in the FP6 IST-E2R project on reconfigurability; she also serves as technical manager for the University of Athens in the FP6 IST-LIAISON project, which focuses on location based services in working environments. Dr Alonistioti is co-editor and co-author of the book entitled “Software defined radio, Architectures, Systems and Functions”, published by John Wiley in May 2003. She has authored over 55 publications in the area of mobile communications and reconfigurable systems and networks. Lazaros Merakos received the Diploma in electrical and mechanical engineering from the National Technical University of Athens, Athens, Greece, in 1978, and the M.S. and Ph.D. degrees in electrical engineering from the State University of New York, Buffalo, in 1981 and 1984, respectively. From 1983 to 1986, he was on the faculty of the Electrical Engineering and Computer Science Department, University of Connecticut, Storrs. From 1986 to 1994, he was on the faculty of the Electrical and Computer Engineering Department, Northeastern University, Boston, MA. During the period 1993D1994, he served as Director of the Communications and Digital Processing Research Center, Northeastern University. During the summers of 1990 and 1991, he was a Visiting Scientist at the IBM T. J. Watson Research Center, Yorktown Heights, NY. In 1994, he joined the faculty of the University of Athens, Athens, Greece, where he is presently a Professor in the Department of Informatics and Telecommunications, and Director of the Communication Networks Laboratory (UoA-CNL) and the Networks Operations and Management Center. Since 1995, he is leading the research activities of UoA-CNL in the area of mobile communications, in the framework of the Advanced Communication Technologies and Services (ACTS) and Information Society Technologies (IST) programs funded by the European Union (projects RAINBOW, Magic WAND, WINE, MOBIVAS, POLOS, ANWIRE, E2R, LIAISON). His research interests are in the design and performance analysis of communication networks, and wireless/mobile communication systems and services. He has authored more than 190 papers in the above areas. Dr. Merakos is Chairman of the Board of the Greek Universities Network, the Greek Schools Network, and Member of the Board of the Greek Research Network. In 1994, he received the Guanella Award for the Best Paper presented at the International Zurich Seminar on Mobile Communications.     

软交换呼叫模型的研究与设计

呼叫模型是软交换设计的核心,软交换呼叫模型设计应体现网络融合及控制分离的特点。文中提出一种适合软交换特点的呼叫模型,该呼叫模型的设计借鉴并作了成熟的智能网呼叫模型改进,借用其连接模型和业务接口,同时增强媒体控制能力,使之与H.248/MEGACO媒体网关控制协议相配合,实现呼叫控制与媒体承载、业务逻辑与呼叫控制的分离。它支持多协议接入,满足开放式业务的需求,具有较好的灵活性和扩展性,可以较好地满足软交换的功能需求。     

文本挖掘中同义与关联词集的构造算法研究

通过分析文本挖掘中的2个关键步骤——文本特征空间构造和相似距离度量,指出流行的文本挖掘过程中存在着大量同义和关联噪声。大量存在的同义词和关联词,造成文本特征空间无法准确表达文本语义以及高维计算复杂性问题。利用潜在语义分析和关联规则挖掘构造同义和关联词集,用于减少文本特征空间中的同义词和关联词,降低信息冗余,改进挖掘效率。文中对相应的算法进行了描述,实验结果令人满意。     

Industrial development and structural adaptation in Taiwan: someissues of learned entrepreneurship

The industrialization of Taiwan has been a remarkable phenomenon. This paper discusses changes in Taiwan's manufacturing industries and the response of both government and private enterprises to the challenges presented by a dynamic environment and by global competition. Several cases are discussed in light of the activities and adjustments on the part of government and of the public sector, of small and medium business, and of high-tech industries. Government participation over has been and will remain pivotal in economic growth and in achieving adjusted positioning. The accelerated sociopolitical movements toward democracy, the bureaucratic management of public issues, and the political and economic interactions between Taiwan and China, exert significant effects on the industrial structure and on government's role in directing the industrial evolution. This article presents an integrated reasoning of Taiwan's economic success. It reveals that the neoclassical doctrine of market efficiency is fundamentally valid, and that the effective commercialization of national technological capability has created Taiwan's industrial evolution. Market governance proved to be an efficient short-term policy instrument when the latecomer strategy of cost leadership was applied. A conceptual model of industrial competition and technology commercialization is also proposed to facilitate the methodological analysis. This study concludes that learning capability and human capital will determine the endurance of Taiwan's industrial success, and that entrepreneurship must be learned by the state, as well as by the private firms     

Electromagnetic energy and food processing

The use of electromagnetic energy in food processing is reviewed with respect to food safety, nutritional quality, and organoleptic quality. The effects of nonionizing radiation sources such as microwave and radio-frequency energy and ionizing radiation sources, e.g. radioactive cobalt-60 and caesium-137, on the inactivation of microbes and nutrients are compared with those of conventional heating processes both in terms of their kinetic behavior and their mechanisms of interaction with foods. The kinetics of microwave and conventional thermal inactivation are considered for a generalized nth-order model based on time and temperature conditions. However, thermal inactivation effects are often modeled by 1st-order kinetics. Microbial and nutrient inactivation by ionizing sources are considered for a 1st-order model based on radiation dose. Both thermal and radiation resistance concepts are reviewed and some typical values of radiation resistance are given for sensitive vegetative bacterial cells, yeasts, and molds and for resistant bacterial spores and viruses. Nonionizing microwave energy sources are increasingly used in home and industrial food processing and are well-accepted by the American public. But, despite recent Food and Drug Administration approval of low and intermediate ionizing radiation dose levels for grains and other plants products and the fact that irradiated foods are sold in more than 20 countries of the world, public fears in the U.S. about nuclear energy may limit the role of ionizing radiation in food processing and preservation and may also limit the use of nuclear fuels as an alternate source of electrical energy.