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1.
The Web is a universal repository of human knowledge and culture which has allowed unprecedented sharing of ideas and information in a scale never seen before. It can also be considered as a universal digital library interconnecting digital libraries in multiple domains and languages. Beside the advance of information technology, the global economy has also accelerated the development of inter-organizational information systems. Managing knowledge obtained in multilingual information systems from multiple geographical regions is an essential component in the contemporary inter-organization information systems. An organization cannot claim itself to be a global organization unless it is capable to overcome the cultural and language barriers in their knowledge management. Cross-lingual semantic interoperability is a challenge in multilingual knowledge management systems. Dictionary is a tool that is widely utilized in commercial systems to cross the language barrier. However, terms available in dictionary are always limited. As language is evolving, there are new words being created from time to time. For examples, there are new technical terms and name entities such as RFID and Baidu. To solve the problem of cross-lingual semantic interoperability, an associative constraint network approach is investigated to construct an automatic cross-lingual thesaurus. In this work, we have investigated the backmarking algorithm and the forward evaluation algorithm to resolve the constraint satisfaction problem represented by the associative constraint network. Experiments have been conducted and show that the forward evaluation algorithm outperforms the backmarking one in terms of precision and recall but the backmarking algorithm is more efficient than the forward evaluation algorithm. We have also benchmarked with our earlier technique, Hopfield network, and showed that the associate constraint network (either backmarking or forward evaluation) outperforms in precision, recall, and efficiency.  相似文献   

2.
Constraint aggregation is the key for efficient structural optimization when using a gradient-based optimizer and an adjoint method for sensitivity analysis. We explore different methods of constraint aggregation for numerical optimization. We analyze existing approaches, such as considering all constraints individually, taking the maximum of the constraints and using the Kreisselmeier–Steinhauser (KS) function. A new adaptive approach based on the KS function is proposed that updates the aggregation parameter by taking into account the constraint sensitivity. This adaptive approach is shown to significantly increase the accuracy of the results without additional computational cost especially when a large number of constraints are active at the optimum. The characteristics of each aggregation method and the performance of the proposed adaptive approach are shown by solving a wing structure weight minimization problem.  相似文献   

3.
A novel artificial neural network heuristic (INN) for general constraint satisfaction problems is presented, extending a recently suggested method restricted to boolean variables. In contrast to conventional ANN methods, it employs a particular type of non-polynomial cost function, based on the information balance between variables and constraints in a mean-field setting. Implemented as an annealing algorithm, the method is numerically explored on a testbed of Graph Coloring problems. The performance is comparable to that of dedicated heuristics, and clearly superior to that of conventional mean-field annealing.  相似文献   

4.
In this article, we introduce a new solving framework based on using alternatively two local-search algorithms to solve constraint satisfaction and optimization problems. The technique presented is based on the integration of local-search algorithm as a mechanism to diversify the search instead of using a build on diversification mechanisms. Thus, we avoid tuning the multiple parameters to escape from a local optimum. This technique improves the existing methods: it is generic especially when the given problem can be expressed as a constraint satisfaction problem. We present the way the local-search algorithm can be used to diversify the search in order to solve real examination timetabling problems. We describe how the local-search algorithm can be used to assist any other specific local-search algorithm to escape from local optimality. We showed that such framework is efficient on real benchmarks for timetabling problems.  相似文献   

5.
Scheduling activities in concurrent product development process is of great sig-nificance to shorten developements lead time and minimize the cost.Moreover,it can eliminate the unnecessary redesign periods and guarantee that serial activities can be executed as concurrently as possible,This paper presents a constraint satisfaction neural network and heuristic combined approach for concurrent activities scheduling.In the combined approack,the neural network is used to obtain a feasible starting time of all the activities based on sequence constraints ,the heuristic algorithm is used to obtain a feasible solution of the scheduling problem based on resource constrainsts.The feasible scheduling solution is obtained by a gradient optimization function .Sim-ulations have shown that the proposed combined approach is efficient and fasible with respect to concurrent activities scheduling.  相似文献   

6.
搜索控制问题是大多数人工智能问题求解面临的一个根本间题,而约束满足是解决这一问题的常用方法之一它源于机器视觉领域中的情景标识任务,如今在人工智能的众多领域(如规划、调度、时序推理)中获得了广泛的应用,受到了人工智能界的高度重视.在近几期的UCAI和AAAI等国际人工智能会议上这方面的内容均占有一定的比重,《A币ficial In-telligence》杂志曾于1992年出了一期约束满足问题的专辑  相似文献   

7.
Background and objective: Medical social networking platforms provide virtual spaces ensuring the interaction between different healthcare participants. As a part of the exchange, these spaces allow subscribers to upload medical images, describing different medical cases for an analysis or an interpretation proposal. Facing this expected huge amount of uploaded images generated daily, it is needed to engage new mechanisms to effectively deal with this circumstance, for enhancing the search function process of medical images, based on what is uploaded. To overcome this issue, setting up of images visual searching based on a content-based medical image retrieval scheme is the solution. More clearly, such mechanism will help and motivate medical social networking subscribers to find visually similar stored images. Methods: To ensure this task, the development of this mechanism, technically, is based mainly on a fusion of three visual features, which offers a flexible and more precision. It is reinforced by a weighted distance approach through attributing weights for feature vectors to scale up the performance. Indeed, the displayed results of this system can be updated based on user's intention by a user interactive feedback mechanism to indicate the truly relevant images. Results: We provide the theoretical performance of our scheme. Extensive experiments were conducted on a categorically classified collection containing 500 images. We conduct a practical evaluation on this dataset classes, putting returned results in a comparative study with other models results, existing in the literature. Conclusions: The proposed scheme preserves the efficiency of the search task. As theoretically and experimentally established, our scheme offers an effective image retrieval model that can support different subscribers' expectations. The relevance feedback mechanism can keep the dynamism of the system, thus offering a continuous searching result evolution. Experimentation outcomes indicate better findings compared with the other models.  相似文献   

8.
基于动态约束网络的约束优化分解   总被引:1,自引:0,他引:1  
约束网络通过对较大规模的任务和问题的分解,传递了并行工程产品开发过程中的各多功能小组之间必然存在的相互制约、相互依赖的关系。在任务和问题简单分解的过程中,由于所得到的子问题之间通常是不能完全独立的,因而只能在有限程度上降低难度、简化问题。在分析了约束求解的研究现状和不足的基础上,提出了一种基于动态约束的约束优化分解方法,使得各个子任务、子问题间的关系得到进一步的分解,从而在满足原要求的基础上,得到优化的结果。  相似文献   

9.
随着计算机科学技术的发展,计算机互联网技术已经成为了人类社会网络信息共享的最大平台,世界各个国家和大型公司也非常重视计算机互联网数据库系统的发展.截至目前为止,经过多年的科学研究,许多大型互联网企业已经初步了解了互联网的发展构架,但是,由于互联网是一个将全世界连接起来的大网络,这就导致在互联网中潜藏着很多安全问题.针对这样的情况,本文将具体结合目前计算机网络信息安全管理的实际情况,谈一谈应当如何加强计算机网络信息安全管理.  相似文献   

10.
一种基于形式概念分析的问答系统答案抽取的研究   总被引:3,自引:0,他引:3  
为了在问答系统中尝试回答更加复杂的问题,有必要存在一种原理性的方法来动态产生不同的问答策略。提出在问答系统中使用形式概念分析(FCA)来抽取答案。在抽取过程中,首先在常问问题集(FAQs)中寻找已经存在的问题,如果在FAQs中的答案不满足用户的需求,再通过搜索引擎获取相关的文档。接着利用这些文档中前N个文档构建概念格,进而采用概念匹配在格中抽取答案。对于不同的问题,使用不同的策略进行匹配和抽取答案。  相似文献   

11.
约束满足问题是人工智能领域中最基本的NP完全问题之一。多年来,随着约束满足问题的深入研究,国内外学者提出多种实例模型。其中,RB模型是一种能生成具有精确相变的增长域约束满足问题实例,其求解难度极具挑战性。为了寻找其求解的新型高效算法,促进约束可满足问题的RB模型求解算法领域的研究,首先从约束满足问题的模型发展、求解技术进行分析;其次,对各类求解RB模型实例算法进行梳理,将求解的算法文献划分为回溯启发式类、信息传播类和元启发式类相关改进算法,从算法原理、改进策略、收敛性和精确度等方面进行对比综述;最后给出求解RB模型实例算法的研究趋势和发展方向。  相似文献   

12.
Product development of today is becoming increasingly knowledge intensive. Specifically, design teams face considerable challenges in making effective use of increasing amounts of information. In order to support product information retrieval and reuse, one approach is to use case-based reasoning (CBR) in which problems are solved “by using or adapting solutions to old problems.” In CBR, a case includes both a representation of the problem and a solution to that problem. Case-based reasoning uses similarity measures to identify cases which are more relevant to the problem to be solved. However, most non-numeric similarity measures are based on syntactic grounds, which often fail to produce good matches when confronted with the meaning associated to the words they compare. To overcome this limitation, ontologies can be used to produce similarity measures that are based on semantics. This paper presents an ontology-based approach that can determine the similarity between two classes using feature-based similarity measures that replace features with attributes. The proposed approach is evaluated against other existing similarities. Finally, the effectiveness of the proposed approach is illustrated with a case study on product–service–system design problems.  相似文献   

13.
个性化信息服务越来越成为信息检索领域研究的热点.将贝叶斯网络和互信息相结合,用于个性化检索的用户建模中,建立了一个能同时表达特征词的统计分布和特征词间的语义相关性的用户模型.模型以贝叶斯网络结构为框架,包含了特征词的概率统计信息和特征词间互信息,并引入了时间机制.实验结果表明,用该模型进行信息检索,在查全率和查准率方面都得到了提高.  相似文献   

14.
Program comprehension is a key activity throughout software maintenance and reuse. The knowledge acquired through comprehending programs can guide engineers to perform various kinds of software maintenance and reuse tasks. The effective comprehension strategy and the associated efficient approach, as well as the sophisticated tool support, are the indispensable elements for an entire solution to program comprehension to reduce the high costs of this nontrivial activity. This paper presents an objective-oriented comprehension strategy, contrasting to the traditional comprehensive understanding strategy in the literature. It is a kind of on-demand understanding for specific tasks and more effective in practice. In addition, using multiple information sources to understand programs is proposed with the corresponding framework. From these two points of views, we propose a feature-oriented program comprehension approach using requirement documentation. This approach aims at a specific category of feature-related software maintenance and reuse tasks. Case studies are conducted to evaluate the proposed solution. Results from the studied cases show that the experimental prototype provides more explicit advices for software engineers when performing these tasks.  相似文献   

15.
An information resource network (IRN) is a time-ordered and potentially interrelated set of information elements. Examples include papers within a research domain, blog postings dealing with a certain topic, and information records within a company. We present a structured analysis to identify influential building blocks and linkages in a general IRN and show that our approach can be used for large networks of information nodes. Our method compensates for biases that can emerge at the edges of such time-dependent networks. Importantly, our focus is on the information elements and not on the authors of such information. We illustrate this process using one example of a resource network — research papers in a given domain. Our method can be implemented in any domain that can be represented as time-ordered, interrelated components of information sets.  相似文献   

16.
提出一种以骨干通信网络流量特征参数告警信息为基础的关联分析方法,首先提取通信网络中多个与异常事件相关的相对粗粒度的流量特征参数,将这些特征参数看做是随时间变化的信号(以下称为流量特征信号),通过流量特征信号分析获得异常事件的多个告警信息;然后采用Apriori算法进行告警信息关联分析,获得告警信息与异常事件的关联规则。实际网络流量数据的分析表明:使用上述规则能有效地发现骨干通信网异常事件。  相似文献   

17.
当前取证信息自动检索系统未对取证信息潜在检索风险进行过滤,导致对取证信息的检索风险控制效果差、检索效率低、误差高的问题,为此设计一种总线网络取证信息自动检索风险控制系统。将输入的取证信息在采集模块中进行收集,检索风险控制模块对采集的取证信息信息进行风险过滤和风险控制后,发送给DSP进行自动检索,采用STM32F407设计接口电路连接采集模块和检索风险控制模块,完成硬件部分的改进;选择高检索相关度节点,利用节点内置文档实现取证信息检索风险的控制,完成软件部分设计。实验结果表明,该系统的检索风险控制效果好,控制精度可达到80%以上,能够为用户提供更有效、更安全的权证信息检索结果。  相似文献   

18.
在线社交网络中信息传播模式的特征分析   总被引:1,自引:0,他引:1  
在线社交网络以其独特的传播优势,已成为一种流行的社交媒体平台。针对在线社交网络中信息传播模式的形式特点,结合传染病动力学原理,提出了在线社交网络中的信息传播模型。模型考虑了不同用户行为对传播机理的影响,并建立了不同用户节点的演化方程组,模拟了信息传播的过程,分析了不同类型的用户在网络中的行为特征以及影响信息传播的主要因素。实验结果表明:不同类型的用户在信息传播过程中有着特定的行为规律,信息不会无限制地传播,并在最终达到平稳状态,并且传播系数和免疫系数越大,信息传播达到稳态的速度就越快。  相似文献   

19.
This paper discusses the performance analysis of two generic fundamental parallel search techniques on shared memory multi-processor systems in solving the constraint satisfaction problem (CSP). Probabilistic analysis on their expected computation steps needed and their inherent load-balancing capability is performed. Corresponding experimental results are alsoprovided to verify the correctness of the proposed analysis. This fundamental analysis approach can be further applied to various advanced parallel search techniques or various problem solving techniques on parallel platforms. This research was supported in part by the University of Texas at San Antonio under the Faculty Research Award program  相似文献   

20.
空间信息网络具有高动态拓扑,大时空尺度、多样化业务和星上资源受限等特点。随着星间组网技术的日益成熟和航天活动的不断增加,航天器用户的动态多址接入问题已经成为影响网络性能的关键因素,得到了国内外研究机构的广泛关注。首先分析了典型多址接入技术的主要特点;然后在空间信息网络场景中,对基于竞争的分布式接入控制、基于无冲突的集中式接入控制以及多协议混合接入控制等三种多址接入技术进行了性能分析,对比剖析了三种多址接入方法的优势与不足。最后,分别提出了典型多址接入技术在未来空间信息网络中的典型应用场景和适应性改造方法。  相似文献   

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