通用在线考试系统的设计与实现

目前的大多数考试系统都局限于某个学科或者专业,而忽略其通用性的研究,通过对通用在线考试系统进行需求分析,了解系统的功能需求,设计出系统功能模块例如学生考试、题库管理、考卷评分和考试分析。给出关键模块的实现细节,并实现一个完善的通用在线考试系统。     

社区问答系统研究综述

作为一种新兴的知识共享模式,社区问答系统(CQA)具有交互性、开放性的特点,能够更好地满足为用户提供个性化的信息服务的需求。对社区问答系统的研究及应用现状进行综述,系统阐述了用户行为模式、内容质量检测、问题检索等CQA中主要问题的研究以及CQA在其他媒体中的应用。最后展望了CQA中下一步值得研究的问题。本讨论有助于进一步丰富和拓展CQA的研究。     

问答系统研究现状

问答系统是信息检索的高级形式,也是该领域的研究重点和热点。该文首先给出问答系统的定义,然后对现有各类问答系统进行了介绍,并对其核心技术、测评标准进行了分析,最后对问答系统的发展方向进行了展望。     

海安方言的“可VP”句式

本文描绘和分析了存在于海安方言中的“可ＶＰ”问句在疑问词、疑问句式、疑问焦点及停顿等方面不同于一般方言的特殊性,并以《西游记》、《红楼梦》等名著中的例子进行参证。最后,指明这种句式是非问的性质。     

基于Client/Server模式的智能抽题算法

文章介绍了一种应用于Client/Server模式的计算机辅助测试系统中的智能抽题算法。该算法采用抽题脚本动态获取题目信息,运用优化替换技术对抽取的脚本草稿进行替换修正,具有抽题快捷、网络传输量小、对数据库的完备性要求较低、通用性较强的优点。     

Evaluating ASP and Commercial Solvers on the CSPLib

This paper deals with four solvers for combinatorial problems: the commercial state-of-the-art solver ILOG oplstudio, and the research answer set programming (ASP) systems dlv, smodels and cmodels. The first goal of this research is to evaluate the relative performance of such systems when used in a purely declarative way, using a reproducible and extensible experimental methodology. In particular, we consider a third-party problem library, i.e., the CSPLib, and uniform rules for modelling and instance selection. The second goal is to analyze the marginal effects of popular reformulation techniques on the various solving technologies. In particular, we consider structural symmetry breaking, the adoption of global constraints, and the addition of auxiliary predicates. Finally, we evaluate, on a subset of the problems, the impact of numbers and arithmetic constraints on the different solving technologies. Results show that there is not a single solver winning on all problems, and that reformulation is almost always beneficial: symmetry-breaking may be a good choice, but its complexity has to be carefully chosen, by taking into account also the particular solver used. Global constraints often, but not always, help opl, and the addition of auxiliary predicates is usually worth, especially when dealing with ASP solvers. Moreover, interesting synergies among the various modelling techniques exist.     

Handling distributed authorization with delegation through answer set programming

Distributed authorization is an essential issue in computer security. Recent research shows that trust management is a promising approach for the authorization in distributed environments. There are two key issues for a trust management system: how to design an expressive high-level policy language and how to solve the compliance-checking problem (Blaze et al. in Proceedings of the Symposium on Security and Privacy, pp. 164–173, 1996; Proceedings of 2nd International Conference on Financial Cryptography (FC’98). LNCS, vol.1465, pp. 254–274, 1998), where ordinary logic programming has been used to formalize various distributed authorization policies (Li et al. in Proceedings of the 2002 IEEE Symposium on Security and Privacy, pp. 114–130, 2002; ACM Trans. Inf. Syst. Secur. (TISSEC) 6(1):128–171, 2003). In this paper, we employ Answer Set Programming to deal with many complex issues associated with the distributed authorization along the trust management approach. In particular, we propose a formal authorization language providing its semantics through Answer Set Programming. Using language , we cannot only express nonmonotonic delegation policies which have not been considered in previous approaches, but also represent the delegation with depth, separation of duty, and positive and negative authorizations. We also investigate basic computational properties related to our approach. Through two case studies. we further illustrate the application of our approach in distributed environments.     

中文问句分类特征的研究

针对"不同的问句分类特征对问句分类的影响不相同,提取和处理这些特征的时间复杂度也不相同"的问题,提取问题疑问词、核心关键词(疑问词的一二级依存词和问句中心语)的主要义原、核心关键词的首义原、问句主谓宾的主要义原、命名实体、名词单(复)数等六种分类特征,采用支持向量机分类算法,对事实疑问句进行不同特征组合的分类对比实验,发现采用词义消岐技术提取的主要义原不仅对分类的准确率影响明显,而且大幅降低特征向量的维数,减少了处理时间。     

基于ASP的CSP并发系统验证研究

传统并发通信顺序进程(CSP>性质的验证通常使用3个不同的模型层面,从而增加了系统的复杂性和验证 工具开发的难度;同时,主流的并发系统模型验证工具不支持在系统的一次运行中验证多个性质,这也降低了性质验 证的效率。首先将CSP程序转换为ASP程序,然后将CSP进程并发规则和以LTL/CTL公式表示的待验证性质转 换为ASP规则,从而建立了基于ASP验证CSP并发系统性质的统一框架。实验结果表明,基于ASP的CSP并发系 统验证技术易于实现,在保持较高验证效率的同时,能够支持在验证软件的一次执行中验证多条LTL/CTL公式。     

Reasoning with infinite stable models

This paper illustrates extensively the theoretical properties, the implementation issues, and the programming style underlying finitary programs. They are a class of normal logic programs whose consequences under the stable model semantics can be effectively computed, despite the fact that finitary programs admit function symbols (hence infinite domains) and recursion. From a theoretical point of view, finitary programs are interesting because they enjoy properties that are extremely unusual for a nonmonotonic formalism, such as compactness. From the application point of view, the theory of finitary programs shows how the existing technology for answer set programming can be extended from problem solving below the second level of the polynomial hierarchy to all semidecidable problems. Moreover, finitary programs allow a more natural encoding of recursive data structures and may increase the performance of credulous reasoners.