A Novel Segmentation and Feedback Model for Resolving Contention in Optical Burst Switching

A novel segmentation and feedback model (SFM) applied to resolve contention is proposed. Simulation and performance analyses show that the SFM effectively avoids contentions in optical burst switching (OBS). The long delay time of deflection routing and the immature technology of wavelength converters and optical buffers are not deployed in the SFM. The SFM does not only realize fast switching but also allows preemption by higher priority bursts.     

QoS二次流量监管实现

流量监管TP（Traffic Policing）就是对流量进行控制,它通过监督进入网络的流量速率,确保进入的流量被限制在一个合理的范围内。为满足网络中多用户多业务对流量监管的要求,通过对QoS流量监管的模式方法CAR（Committed Access Rate,约定访问速率）的分析研究,在路由平台上实现了QoS二次的流量监管功能,经在三层交换机上测试,证明了监管的有效性。     

一种实现区分服务和带宽公平性的队列管理算法

区分服务(DiffServ)体系对于可靠型(AF)服务的OUT数据包和尽力型(BE)服务的数据包并未提供任何优先处理机制。为避免某AF服务的数据流占用过多的网络带宽，提出了一种名为TD&BF的核心无状态队列管理算法，该算法能在保证AF业务承诺服务速率的前提下，将剩余带宽公平地分配给BE业务及AF业务。     

企业人员受贿罪犯罪形态的认定探讨

企业人员受贿罪存在未遂形态，其既遂与未遂的认定应以行为人是否确实索取或收受贿赂，为他人谋取利益，数额较大为标准；对该罪共同犯罪的认定，则应根据参与共同受贿的主体身份不同，分为四种情况分别加以认定。     

A changing society and problems of method: a politically committed research type

This essay examines a politically engaged research genre, which follows the biography of the author who founded two journals: one on mathematical models published in English (Quality and Quantity) and one on politically committed social and economic research published in Italian (Inchiesta). The research considered focuses on Italy in the 1950s, the research by Lazarsfeld in Vienna in the 1920s and in the United States in the 1950s and 1960s, and post-1968 politically committed research in Italy. The analysis of such politically committed types of research (all very different from one another in terms of the interpretative model of reality, the methods used and the relations with the tendering party and the people observed) allows one to understand how this kind of research can be performed with very different methods—all of which do, however, seek to modify reality on the grounds of the research results. The metaphor of the crystal and the flame presented by Italo Calvino in order to classify facts and ideas and styles and feelings can also be used to visualise the polarity (and the difficulty/impossibility of contact) that has always been present in sociology between two different tendencies: towards a discipline that offers the most abstract and objective interpretative model of reality possible with the use of mathematical models (the crystal), and, instead, towards a discipline in which an interpretative model of reality is central, one that produces a social change and in which the qualitative and quantitative methods utilised are at the service of this change (the flame). This polarity thus allows us to separate first and foremost all the politically committed research performed by others for different purposes (market research, research to verify some theoretical hypotheses, etc.) but the same polarity also lies within the politically committed research. We can, indeed, identify a type of politically committed research in an area that has, at one extreme, research tending towards the utmost objectivity and scientific quality of the results and where the co-ordinators try to have all the information on the subjects maintaining the greatest possible distance (the subjects must not know they are being observed); at the other extreme, there is a type of research in which the coordinator completely involves the subjects in the gathering of information that will serve to realise a piece of research whose political aims are explicitly shared. For the identification of a sufficiently articulated typology it has been important to consider five dimensions of politically committed research: (a) the characteristics of the research coordinator (his/her belonging to the type and the academic/non-academic professional status) and his/her interpretative model of reality (b) some general characteristics of the research (the tender and funding, the topic choice, the aims, the contributions to the sociological theory, the duration); (c) the research coordinators relations with the political actors (the intensity of the relations, the political use of the research); (d) the relations of the research co-ordinator with the research subjects; (e) the methodological choices (the basic strategies, the methods used, the use of mathematical procedures). The research that exemplifies this typology is all politically committed to the left and was realised in different times and contexts. I start by considering a kind of politically engaged research (co-research) that appeared in Italy in the 1950s; I then analyse two types of politically engaged research realised in Austria at the end of the 1920s and one in the United States in the 1950s; there then follow two kinds of research realised in the 1960s and 1970s in the United States and a further two kinds realised in Italy in the 1970s and early 1980s. In order to have other kinds of research please refer to the two Journals of which I am the editor: one is an English language journal of mathematical models (Quality and Quantity, International Journal of Methodology, founded in 1966 and published today by Kluwer of Amsterdam), and a politically engaged review (Inchiesta, founded in 1971 and still published today by Dedalo of Bari).     

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正SCIENCE CHINA Information Sciences(Sci China Inf Sci),cosponsored by the Chinese Academy of Sciences and the National Natural Science Foundation of China,and published by Science China Press,is committed to publishing highquality,original results of both basic and applied research in all areas of information sciences,including computer science and technology;systems science,control science and engineering(published in Issues with odd numbers);information and communication engineering;electronic science and technology(published in Issues with even numbers).Sci China Inf Sci is published monthly in both print and electronic forms.It is indexed by Academic OneFile,Astrophysics Data System(ADS),CSA,Cabells,Current Contents/Engineering,Computing and Technology,DBLP,Digital Mathematics Registry,Earthquake Engineering Abstracts,Engineering Index,Engineered Materials Abstracts,Gale,Google,INSPEC,Journal Citation Reports/Science Edition,Mathematical Reviews,OCLC,ProQuest,SCOPUS,Science Citation Index Expanded,Summon by Serial Solutions,VINITI,Zentralblatt MATH.     

强快照与强提交读隔离的多键云事务实现方法

当前云环境的存储系统一般只提供弱一致性和单键事务的数据访问功能,具有强一致性或多键事务需求的应用只能自行检测一致性或进行事务管理,增加了云应用开发的复杂度。这些要求高一致性和高可用性的云应用,对云存储系统的事务实现提出了新的挑战。在Megastore串行化事务实现方案的基础上,提出了基于读写集对比的事务强快照隔离和强提交读隔离方案,将并发事务之间读写冲突的判断提前,从而减少冲突事务回滚时引发的额外消耗。基于云存储系统Cassandra实现了两种方案,并针对云应用事务的访问模式,设计了实验验证框架。通过与Megastore事务实现方案的对比,验证了强快照和强提交读事务隔离方案能获得更高并发度的优化效果。     

论遏制流动人口犯罪的对策

从犯罪主体年龄结构、犯罪动机、作案地点和作案方式及其侵害对象方面,归纳了我国流动人口犯罪的特征;就社会背景、犯罪心理、人口文化素质及被害人安全防范意识方面,分析了导致流动人口犯罪的原因;提出了遏制流动人口犯罪的对策。     

Complementing zero-knowledge watermark detection: Proving properties of embedded information without revealing it

Zero-knowledge Watermark Detection (ZKWMD) is a promising and powerful means to improve the security of digital watermarking schemes in the context of various copyright-protection applications: in contrast to standard watermarking schemes, ZKWMD allows a proving party to prove to untrusted parties the presence of hidden information (embedded in digital data) without requiring to disclose this information or any other secrets necessary to detect its presence. However, typical applications presume the embedded information to have certain properties such as to be drawn from a specific probability distribution, and/or to have a specific form to counter ambiguity attacks. Hence, additional verifications must be performed that are more involved since the input to a ZKWMD protocol is cryptographically concealed. We present concrete and practical protocols to securely perform these verifications as complementary protocols to ZKWMD. In this context we consider two different approaches whose deployment depends on the underlying applications: the first one allows to securely prove that the concealed information (watermark) suffices certain desired properties, whereas the second approach allows both parties to jointly, securely and verifiably generate this information with the desired properties. The information in this document reflects only the author's views, is provided as is, and no guarantee or warranty is given or implied that the information is fit for any particular purpose. The user thereof uses the information at its sole risk and liability.