基于IFC标准的BIM自适应分词方法

建筑信息模型(BIM)已经成为建筑行业信息技术应用的有效方案.随着BIM数据不断增长,为了高效使用BIM数据,很多研究将自然语言处理(NLP)引入BIM应用中.在中文环境中,由于缺乏建筑行业的术语特征,导致基础环节的中文分词在建筑领域BIM应用中的适应性较差.通过分析当前流行的BIM数据格式工业基础类(industry...     

A probabilistic reasoning model: Formulation and control strategy

It has been recognized that past experiences of a decision maker often plays a pivotal role in solving new problem instances. Therefore, the ability to model human reasoning processes has become an important subject of research in recent years. In many applications, the reasoning process must deal with uncertainty inherent in the problem domain. This research addresses the issue of supporting the model formulation and data acquisition processes for situations that (i) operate under uncertain conditions, and (ii) utilize evidential information that is gathered in stages. A theoretical framework is presented for the probabilistic formulation of the reasoning process that incorporates past experiences. The model is validated by testing its performance on simulated data, and is shown to work well when a sufficiently large number of cases are available for estimating probabilities. The probabilistic reasoning system can revise beliefs in an intuitively appealing and theoretically sound manner when information is acquired in an incremental fashion. Two dynamic information gathering strategies are discussed for such a reasoning system, one using information theoretic techniques, and the other using decision theoretic techniques.     

Continuous probabilistic model building genetic network programming using reinforcement learning

Recently, a novel probabilistic model-building evolutionary algorithm (so called estimation of distribution algorithm, or EDA), named probabilistic model building genetic network programming (PMBGNP), has been proposed. PMBGNP uses graph structures for its individual representation, which shows higher expression ability than the classical EDAs. Hence, it extends EDAs to solve a range of problems, such as data mining and agent control. This paper is dedicated to propose a continuous version of PMBGNP for continuous optimization in agent control problems. Different from the other continuous EDAs, the proposed algorithm evolves the continuous variables by reinforcement learning (RL). We compare the performance with several state-of-the-art algorithms on a real mobile robot control problem. The results show that the proposed algorithm outperforms the others with statistically significant differences.     

灰色神经网络模型及其应用

灰色建模要求的样本点少,不必有较好的分布规律,而且计算量少,操作简便。而BP网络学习样本时,会反馈校正输出的误差,具有并行计算、分布式信息存储、强容错力、自适应学习功能等优点。本文将灰色预测建模和神经网络技术融合起来,建立灰色神经网络模型(GNNM)。提出计算残差序列和新的预测值的公式。用于发酵动力学预测,结果表明,灰色神经网络模型在预测精度方面优于常规灰色模型。该模型的算法概念明确,计算简便,有较高的拟合和预测精度,拓宽了灰色模型的应用范围。     

A new model for selfish routing

In this work, we introduce and study a new, potentially rich model for selfish routing over non-cooperative networks, as an interesting hybridization of the two prevailing such models, namely the KPmodel [E. Koutsoupias, C.H. Papadimitriou, Worst-case equilibria, in: G. Meinel, S. Tison (Eds.), Proceedings of the 16th Annual Symposium on Theoretical Aspects of Computer Science, in: Lecture Notes in Computer Science, vol. 1563, Springer-Verlag, 1999, pp. 404–413] and the Wmodel [J.G. Wardrop, Some theoretical aspects of road traffic research, Proceedings of the of the Institute of Civil Engineers 1 (Pt. II) (1952) 325–378].     

Adaptive routing with stale information

We investigate the behaviour of load-adaptive rerouting policies in the Wardrop model where decisions must be made on the basis of stale information. In this model, each one of an infinite number of agents controls an infinitesimal amount of flow, thus contributing to a network flow which induces latency. In our dynamic extension of this model, agents are activated in a concurrent and asynchronous fashion and may reroute their flow with the aim of reducing their sustained latency. It is a well-known problem that in settings where latency information is not always up-to-date, such behaviour may lead to oscillation effects which seriously harm network performance. Two quantities determine the difficulty of avoiding oscillation: the steepness of the latency functions and the maximum possible age of the information T$T$.     

Fractional alpha stable network traffic model and its application in QoS routing

It is not a simple and trivial work to set up an appropriate network traffic model. A fractional Alpha model is proposed in this paper and two proofs based on flow and session level, respectively, are given. Based on this model, the lower bound for the residual of the queueing distribution is deduced. Comparing the residual distribution function (RDF) based on our model with it based on other models, we find our formula matches the real RDF better. Based on this formula, we can predict the need for forwarding performance. Then a novel QoS routing algorithm based on this prediction is proposed. Last we demonstrate a simple example to denote how our algorithm can effectively improve the utility of bandwidth and amount of traffic and guarantee QoS.     

建筑结构模型的四边形网格生成算法

为提高建筑结构有限元分析计算的效率,提出建筑结构模型的四边形网格生成算法．首先采用改进的折半查找算法快速建立相应的结构模型索引信息;然后根据四边形网格划分的原则调整模型边界;最后采用分区域模板法对整体结构模型进行四边形网格的自动生成．算例表明该算法可以根据有限元分析计算中模型的特点简化模型,降低计算时间．     

基于局域信息的社交网络信息传播模型

针对传统传播模型更适用于均匀网络而无法有效应用于现实非均匀无标度社交网络的问题,提出一种基于用户局域信息的社交网络信息传播模型。模型中考虑了无标度网络中用户间拓扑特征差异和用户影响力不同对信息传播的影响,根据节点周边邻居节点的感染情况和权威性计算感染概率,模拟现实社交网络中的信息传播情况。通过在采集的真实微博网络数据上进行仿真实验,结果表明该模型较传统的SIR模型更能体现社交网络中信息传播的快速性与范围的广泛性;同时,通过调整模型中的相关参数,验证了相关管控措施对传播效果的影响。     

基于物元的流程工业MES信息表示与信息维模型应用

流程工业信息集成与管理需要对各类数据、信息进行统一规范。根据流程工业的特点和MES的功能模型,提出了采用动态物元和事元三元有序元组形式语言表述流程工业生产信息的方法,结合聚丙烯环管反应器提出了基于流程工业生产信息的物元可拓信息维模型。提出的方法合理、实用、简便,在流程工业信息集成管理等方面具有较好的应用前景。     

Knowledge types: a practical approach to guide knowledge engineering in domains of building design

Abstract: This paper presents experiences and findings achieved through several expert system projects in domains of technical buiding design. The main focus is on knowledge acquisition and knowledge decomposition. Different approaches are presented and discussed. Four types of knowledge are presented: object knowledge, performance knowledge, event knowledge and metaknowledge, and the applicability of this classification to building design is justified. The paper includes a listing of experiences gained by real world testing of an expert system, and finally we outline guidelines to knowledge engineering in the domain of technical building     

信息加密技术在计算机网络安全中的应用探讨

随着计算网络的日益普遍化,它的安全问题也变得日益重要。本文首先简介了信息加密技术,分析了当前形势下计算机网络安全的重要性,并探讨了信息加密技术在计算机网络安全中的应用。     

A secure routing model based on distance vector routing algorithm

Distance vector routing protocols have been widely adopted as an efcient routing mechanism in current Internet,and many wireless networks.However,as is well-known,the existing distance vector routing protocols are insecure as it lacks of efective authorization mechanisms and routing updates aggregated from other routers.As a result,the network routing-based attacks become a critical issue which could lead to a more deteriorate performance than other general network attacks.To efciently address this issue,this paper,through analyzing the routing model and its security aspect,and presents a novel approach on guaranteeing the routing security.Based on the model,we present the security mechanism including the message exchange and update message security authentication mechanism.The suggested approach shows that the security mechanism can efectively verify the integrity and validate the freshness of routing update messages received from neighbor nodes.In comparison with exiting mechanisms(SDV,S-RIP etc),the proposed model provides enhanced security without introducing significant network overheads and complexity.     

基于 BIM 和本体的建筑不规则类型审查

建筑不规则类型审查是建筑抗震审查的重要组成部分,对建筑抗震安全有重要意义。为提高审查 效率和准确性,提出一套基于建筑信息模型(BIM)和本体的建筑不规则类型审查方法。首先解析梳理建筑不规则 类型审查规范条文,然后将规范条文转译成计算机可识别的语义审查规则,并根据审查逻辑构建建筑不规则类型 审查本体;其次从待审查建筑的 BIM 文件中抽取审查信息,如楼层开洞面积,基于模板匹配算法从结构计算书 自动抽取审查所需计算结果参数,如扭转位移比;接着基于建筑不规则类型审查本体组织审查信息,利用审查规 则推理获得审查结果,进而生成审查报告。最后以某建筑为例验证了该方法的可行性和较强地扩展能力,为进一 步实现建筑抗震审查的自动化奠定了技术基础。     

一种基于入侵检测的空间网络安全路由技术

随着空间信息网络在各领域尤其是军方的广泛应用,空间网络安全技术成为研究人员越来越关注和重视的研究方向,其中空间网络的路由安全是重要的研究热点之一.针对基于入侵检测的空间网络安全路由技术进行了研究,以无线Mesh网络开发的OLSR路由协议为例,对空间信息网络中基于入侵检测的安全路由技术进行仿真分析,证明了此安全机制的可行性.     

一种P2P网络信息分类检索模型研究

P2P是在分布式自治系统与异构系统之间直接进行资源、服务和信息共享的系统,分布式P2P模型中存在安全性差、流量大和搜寻时间长等弱点,为了解决这些问题,利用"局部访问"原理,提出了一种能够根据历史访问的统计的分类搜索的分布式P2P模型的搜索方法,改善了分布式P2P模型的信息搜索性能,从而为解决上述问题提供了一种有效的途径.     

A model of decision-making with sequential information-acquisition (Part 1)

While most real-life decisions are of necessity made with less than perfect information, there is usually some opportunity to acquire additional information regarding the problem at hand before a final decision is made. It is, of course, the recognition of this fact which has led to the importance now attached to the field of Decision Support Systems. On the other hand, the formal analysis of the sort of decision problem for which Decision Support Systems can be useful appears to have lagged behind the developments in applications. In this paper we develop a model of decision-making in which there is available a variety of informational sources (experiments) which can reduce (though generally not eliminate) the uncertainty associated with the final decisions. Since the informational sources are available only at some cost (either monetarily or in terms of time, or both), the decision-maker must solve two conceptually distinct problems: (1) developing an optimal information-gathering strategy, and (2) developing an optimal final decision strategy, conditional upon the information obtained during the information-gathering process. A theoretical framework is developed here for the analysis of this general problem, and fairly complete solutions are obtained for some interesting special cases; most notably the computer file search problem.     

基于WSN路由节点度模型的楼宇走廊定位算法

针对现有的无线传感器网络(WSN)定位方法应用于结构复杂的楼宇走廊时,存在定位精度较低的问题,提出一种基于WSN路由节点度模型的楼宇走廊定位算法.该算法在路由节点度模型的基础上,先采用基于支持向量回归(SVR)的方法,用少量锚节点定位普通路由节点,达到间接增加锚节点覆盖率的目的;然后采用基于中垂线分割的方法定位随机分布在区域内的未知节点和移动终端.仿真表明:与传统SVR定位算法和核岭回归定位算法相比,所提出的算法精度提高了定位精度,满足室内定位精度要求(1 m~3 m),且降低了对锚节点数量的需求,可运用于楼宇走廊WSN定位.