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多指标决策与评价新方法:带模相似度投影决策法 被引量:2
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作者 江燕燕 《统计与决策》 CSSCI 北大核心 2020年第23期33-36,共4页
文章针对多指标决策与评价问题,提出了一种带模相似度的投影决策法。该方法依据投影决策法的基本思路,给出了该问题的计算步骤,其核心是先确定加权规范化矩阵及加权理想决策向量,从而计算出每个加权决策向量在加权理想决策向量上的投影... 文章针对多指标决策与评价问题,提出了一种带模相似度的投影决策法。该方法依据投影决策法的基本思路,给出了该问题的计算步骤,其核心是先确定加权规范化矩阵及加权理想决策向量,从而计算出每个加权决策向量在加权理想决策向量上的投影及两向量的模相似度,进而得到每个决策向量的评价函数,然后根据评价函数的值对所有决策向量进行排序。有效性分析结果显示,带模相似度的投影决策法能有效利用数据信息。最后,实例应用说明该方法简单易算,排序结果是合理的。 展开更多
关键词 多指标决策与评价 投影决策法 模相似度
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基于相似度建模的永磁牵引列车健康优化控制 被引量:7
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作者 牛刚 江俊杰 《仪器仪表学报》 EI CAS CSCD 北大核心 2017年第2期480-486,共7页
为了保障永磁牵引列车退磁故障发生时的安全性,并缓解由此导致的电制动力下降及闸瓦磨耗加剧问题,提出了一种基于相似度建模(SBM)的健康优化控制方法,该方法通过在线监测数据与历史数据的相似度运算,自适应地估计剩余磁通量并生成最优... 为了保障永磁牵引列车退磁故障发生时的安全性,并缓解由此导致的电制动力下降及闸瓦磨耗加剧问题,提出了一种基于相似度建模(SBM)的健康优化控制方法,该方法通过在线监测数据与历史数据的相似度运算,自适应地估计剩余磁通量并生成最优的空气制动F-v特性曲线。以西门子Syntegra永磁同步电机牵引系统为例,对多种工况下的退磁监测和健康优化控制效果进行了仿真验证,在退磁估计准确性、相对磨耗优化和安全性保障等方面取得了预期的效果。 展开更多
关键词 永磁同步电机 预测与健康管理 优化控制 基于相似
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Similarity Criterion and Scale Effect for Ship Distortion Model Under Combined Loads
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作者 ZHANG Yi-long WEI Peng-yu +3 位作者 DAI Ze-yu WANG Lian ZENG Qing-bo TANG Qin 《船舶力学》 EI CSCD 北大核心 2024年第12期1880-1890,共11页
For the ultimate strength model test evaluation of large ship structures, the distortion model with non-uniform ratio between the main size and the plate thickness size is usually adopted. It is the key to carry out s... For the ultimate strength model test evaluation of large ship structures, the distortion model with non-uniform ratio between the main size and the plate thickness size is usually adopted. It is the key to carry out scale model test to establish a distortion model similar to the real ship structure under combined load. A similarity criterion for ship distortion model under the combined action of bending moment and surface pressure was proposed, and the scale effect for the criterion was verified by a se ries of numerical analysis and model tests. The results show that the similarity criterion for ship distor tion model under combined loads has a certain scale effect. For the model tests of ship cabin struc tures, it is suggested that the scale range between the plate thickness scale and the main dimension scale should be controlled within 2:1, which can be used as a reference for distortion model design and ultimate strength test of large-scale ship structures. 展开更多
关键词 distortion model combined load similarity criteria scale effect ultimate strength test
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水资源生态安全的时空分异特征——以南水北调东线山东段为例 被引量:4
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作者 杨亚锋 高媛媛 +2 位作者 许新宜 袁浩瀚 王红瑞 《南水北调与水利科技(中英文)》 CAS 北大核心 2022年第5期833-841,共9页
为厘清南水北调东线一期工程受水区的水资源生态安全状况,为后续工程相关政策的制定和实施提供参考,基于压力-状态-响应模型探讨水资源生态安全的评价指标体系,进而耦合带模相似度的投影决策法和基尼系数法,研究南水北调东线山东段水资... 为厘清南水北调东线一期工程受水区的水资源生态安全状况,为后续工程相关政策的制定和实施提供参考,基于压力-状态-响应模型探讨水资源生态安全的评价指标体系,进而耦合带模相似度的投影决策法和基尼系数法,研究南水北调东线山东段水资源生态安全的时空分异特征。结果表明:2011—2019年该区域水资源生态安全整体上呈现良性发展态势,综合评价函数值由0.4631增至0.6234。除东营外,各地市在不同程度上表现为:压力子系统指数较高,但由于积极的响应系统,水资源生态安全状况有一定改善。从空间维度来看,研究期内14个地市的水资源生态安全状态总体上保持均衡,基尼系数稳定在0.2左右,但万元GDP用水量等指标的空间差异较为突出。人类活动,尤其用水效率对水资源生态安全的影响日益凸显,南水北调东线工程对山东段受水区的水资源生态安全起到了重要的促进作用。 展开更多
关键词 水资源生态安全 空间均衡 模相似度投影决策法 基尼系数 南水北调东线山东段
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结合用户背景信息的协同过滤推荐算法 被引量:16
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作者 吴一帆 王浩然 《计算机应用》 CSCD 北大核心 2008年第11期2972-2974,共3页
针对个性化推荐系统中协同过滤算法面对的数据稀疏问题,提出了一种结合用户背景信息的推荐算法。该算法充分利用已有的用户数据和领域知识,对用户背景信息的相似度建模,在进行协同过滤前预先填充用户—项评分矩阵。实验表明该方法能够... 针对个性化推荐系统中协同过滤算法面对的数据稀疏问题,提出了一种结合用户背景信息的推荐算法。该算法充分利用已有的用户数据和领域知识,对用户背景信息的相似度建模,在进行协同过滤前预先填充用户—项评分矩阵。实验表明该方法能够有效地提高推荐精度,并且不会带来性能上的瓶颈。 展开更多
关键词 个性化推荐 协同过滤 用户背景信息 相似
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Reducing semantic bias of annotations for semantic web service discovery 被引量:1
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作者 魏登萍 王挺 +1 位作者 唐晋韬 王戟 《Journal of Southeast University(English Edition)》 EI CAS 2010年第1期48-52,共5页
In order to improve the effectiveness of semantic web service discovery, the semantic bias between an interface parameter and an annotation is reduced by extracting semantic restrictions for the annotation from the de... In order to improve the effectiveness of semantic web service discovery, the semantic bias between an interface parameter and an annotation is reduced by extracting semantic restrictions for the annotation from the description context and generating refined semantic annotations, and then the semantics of the web service is refined. These restrictions are dynamically extracted from the parsing tree of the description text, with the guide of the restriction template extracted from the ontology definition. New semantic annotations are then generated by combining the original concept with the restrictions and represented via refined concept expressions. In addition, a novel semantic similarity measure for refined concept expressions is proposed for semantic web service discovery. Experimental results show that the matchmaker based on this method can improve the average precision of discovery and exhibit low computational complexity. Reducing the semantic bias by utilizing restriction information of annotations can refine the semantics of the web service and improve the discovery effectiveness. 展开更多
关键词 semantic web service discovery semantic bias CONTEXT restriction template similarity measure
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Similarity measure on intuitionistic fuzzy sets 被引量:5
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作者 PARK Jean-Ho HWANG Jai-Hyuk +2 位作者 PARK Wook-Je 魏荷 LEE Sang-Hyuk 《Journal of Central South University》 SCIE EI CAS 2013年第8期2233-2238,共6页
Study of fuzzy entropy and similarity measure on intuitionistic fuzzy sets (IFSs) was proposed and analyzed. Unlike fuzzy set, IFSs contain uncertainty named hesitance, which is contained in fuzzy membership function ... Study of fuzzy entropy and similarity measure on intuitionistic fuzzy sets (IFSs) was proposed and analyzed. Unlike fuzzy set, IFSs contain uncertainty named hesitance, which is contained in fuzzy membership function itself. Hence, designing fuzzy entropy is not easy because of many entropy definitions. By considering different fuzzy entropy definitions, fuzzy entropy on IFSs is designed and discussed. Similarity measure was also presented and its usefulness was verified to evaluate degree of similarity. 展开更多
关键词 similarity measure MULTI-DIMENSION discrete data relative degree power interconnected system
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Modeling and monitoring of nonlinear multi-mode processes based on similarity measure-KPCA 被引量:10
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作者 WANG Xiao-gang HUANG Li-wei ZHANG Ying-wei 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第3期665-674,共10页
A new modeling and monitoring approach for multi-mode processes is proposed.The method of similarity measure(SM) and kernel principal component analysis(KPCA) are integrated to construct SM-KPCA monitoring scheme,wher... A new modeling and monitoring approach for multi-mode processes is proposed.The method of similarity measure(SM) and kernel principal component analysis(KPCA) are integrated to construct SM-KPCA monitoring scheme,where SM method serves as the separation of common subspace and specific subspace.Compared with the traditional methods,the main contributions of this work are:1) SM consisted of two measures of distance and angle to accommodate process characters.The different monitoring effect involves putting on the different weight,which would simplify the monitoring model structure and enhance its reliability and robustness.2) The proposed method can be used to find faults by the common space and judge which mode the fault belongs to by the specific subspace.Results of algorithm analysis and fault detection experiments indicate the validity and practicability of the presented method. 展开更多
关键词 process monitoring kernel principal component analysis (KPCA) similarity measure subspace separation
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Improved random noise attenuation using f-x empirical mode decomposition and local similarity 被引量:6
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作者 甘叔玮 王守东 +3 位作者 陈阳康 陈江龙 钟巍 张成林 《Applied Geophysics》 SCIE CSCD 2016年第1期127-134,220,共9页
Conventional f-x empirical mode decomposition(EMD) is an effective random noise attenuation method for use with seismic profiles mainly containing horizontal events.However,when a seismic event is not horizontal,the... Conventional f-x empirical mode decomposition(EMD) is an effective random noise attenuation method for use with seismic profiles mainly containing horizontal events.However,when a seismic event is not horizontal,the use of f-x EMD is harmful to most useful signals.Based on the framework of f-x EMD,this study proposes an improved denoising approach that retrieves lost useful signals by detecting effective signal points in a noise section using local similarity and then designing a weighting operator for retrieving signals.Compared with conventional f-x EMD,f-x predictive filtering,and f-x empirical mode decomposition predictive filtering,the new approach can preserve more useful signals and obtain a relatively cleaner denoised image.Synthetic and field data examples are shown as test performances of the proposed approach,thereby verifying the effectiveness of this method. 展开更多
关键词 Random noise attenuation f-x empirical mode decomposition local similarity dipping event
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Threat Assessment Method Based on Intuitionistic Fuzzy Similarity Measurement Reasoning with Orientation 被引量:15
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作者 WANG Yi LIU Sanyang +2 位作者 NIU Wei LIU Kai LIAO Yong 《China Communications》 SCIE CSCD 2014年第6期119-128,共10页
The aim of this paper is to propose a threat assessment method based on intuitionistic fuzzy measurement reasoning with orientaion to deal with the shortcomings of the method proposed in [Ying-Jie Lei et al., Journal ... The aim of this paper is to propose a threat assessment method based on intuitionistic fuzzy measurement reasoning with orientaion to deal with the shortcomings of the method proposed in [Ying-Jie Lei et al., Journal of Electronics and Information Technology 29(9)(2007)2077-2081] and [Dong-Feng Chen et al., Procedia Engineering 29(5)(2012)3302-3306] the ignorance of the influence of the intuitionistic index's orientation on the membership functions in the reasoning, which caused partial information loss in reasoning process. Therefore, we present a 3D expression of intuitionistic fuzzy similarity measurement, make an analysis of the constraints for intuitionistic fuzzy similarity measurement, and redefine the intuitionistic fuzzy similarity measurement. Moreover, in view of the threat assessment problem, we give the system variables of attribute function and assessment index, set up the reasoning system based on intuitionistic fuzzy similarity measurement with orientation, and design the reasoning rules, reasoning algorithms and fuzzy-resolving algorithms. Finally, through the threat assessment, some typical examples are cited to verify the validity and superiority of the method. 展开更多
关键词 Intuitionistic fuzzy reasoning Threat assessment ORIENTATION Similaritymeasurement
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Cloud model-clustering analysis based evaluation for ventilation system of underground metal mine in alpine region 被引量:6
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作者 YAN Fang LI Zi-jun +4 位作者 DONG Long-jun HUANG Rui CAO Ri-hong GE Ji XU Kai-li 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第3期796-815,共20页
Ventilation system is significant in underground metal mine of alpine region.Reasonable evaluation of ventilation effectiveness will lead to a practical improvement for the maintenance and management of ventilation sy... Ventilation system is significant in underground metal mine of alpine region.Reasonable evaluation of ventilation effectiveness will lead to a practical improvement for the maintenance and management of ventilation system.However,it is difficult to make an effective evaluation of ventilation system due to the lack of classification criteria with respect to underground metal mine in alpine region.This paper proposes a novel evaluation method called the cloud model-clustering analysis(CMCA).Cloud model(CM)is utilized to process collected data of ventilation system,and they are converted into cloud descriptors by CM.Cloud similarity(CS)based Euclidean distance(ED)is proposed to make clustering analysis of assessed samples.Then the classification of assessed samples will be identified by clustering analysis results.A case study is developed based on CMCA.Evaluation results show that ventilation effectiveness can be well classified.Moreover,CM is used alone to make comparison of evaluation results obtained by CMCA.Then the availability and validity of CMCA is verified.Meanwhile,difference of CS based ED and classical ED is analyzed.Two new clustering analysis methods are introduced to make comparison with CMCA.Then the ability of proposed CMCA to meet evaluation requirements of ventilation system is verified. 展开更多
关键词 ventilation system underground metal mine alpine region cloud model cloud similarity Euclidean distance
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User preferences-aware recommendation for trustworthy cloud services based on fuzzy clustering 被引量:1
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作者 马华 胡志刚 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第9期3495-3505,共11页
The cloud computing has been growing over the past few years, and service providers are creating an intense competitive world of business. This proliferation makes it hard for new users to select a proper service amon... The cloud computing has been growing over the past few years, and service providers are creating an intense competitive world of business. This proliferation makes it hard for new users to select a proper service among a large amount of service candidates. A novel user preferences-aware recommendation approach for trustworthy services is presented. For describing the requirements of new users in different application scenarios, user preferences are identified by usage preference, trust preference and cost preference. According to the similarity analysis of usage preference between consumers and new users, the candidates are selected, and these data about service trust provided by them are calculated as the fuzzy comprehensive evaluations. In accordance with the trust and cost preferences of new users, the dynamic fuzzy clusters are generated based on the fuzzy similarity computation. Then, the most suitable services can be selected to recommend to new users. The experiments show that this approach is effective and feasible, and can improve the quality of services recommendation meeting the requirements of new users in different scenario. 展开更多
关键词 trustworthy service service recommendation user preferences-aware fuzzy clustering
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No-reference blur assessment method based on gradient and saliency 被引量:2
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作者 Jia Huizhen Lei Chucong +5 位作者 Wang Tonghan Li Tan Wu Jiasong Li Guang He Jianfeng Shu Huazhong 《Journal of Southeast University(English Edition)》 EI CAS 2021年第2期184-191,共8页
To evaluate the quality of blurred images effectively,this study proposes a no-reference blur assessment method based on gradient distortion measurement and salient region maps.First,a Gaussian low-pass filter is used... To evaluate the quality of blurred images effectively,this study proposes a no-reference blur assessment method based on gradient distortion measurement and salient region maps.First,a Gaussian low-pass filter is used to construct a reference image by blurring a given image.Gradient similarity is included to obtain the gradient distortion measurement map,which can finely reflect the smallest possible changes in textures and details.Second,a saliency model is utilized to calculate image saliency.Specifically,an adaptive method is used to calculate the specific salient threshold of the blurred image,and the blurred image is binarized to yield the salient region map.Block-wise visual saliency serves as the weight to obtain the final image quality.Experimental results based on the image and video engineering database,categorial image quality database,and camera image database demonstrate that the proposed method correlates well with human judgment.Its computational complexity is also relatively low. 展开更多
关键词 no-reference image quality assessment reblurring effect gradient similarity SALIENCY
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Investigation of acoustic scale effects and boundary effects for the similitude model of underwater complex shell-structure 被引量:3
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作者 WANG San-de YANG De-sen LIU Ning 《Journal of Marine Science and Application》 2007年第1期31-35,共5页
In this paper, the acoustic scale effects and boundary effects for the similitude model of underwater complex shell-structure are investigated. The similitude conditions and relations between the similitude model and ... In this paper, the acoustic scale effects and boundary effects for the similitude model of underwater complex shell-structure are investigated. The similitude conditions and relations between the similitude model and its prototype were studied in the references. This paper investigates the acoustic scale effects for the similitude model, which are influenced by loss factor, shear and rotatory inertia. At the same time, the boundary effects which are influenced by surface sound reflection are investigated in the experiment of similitude model. The results show that the acoustic scale effects may be controlled with model designing, the boundary effects can be controlled with experimental designing between the similitude model and its prototype. 展开更多
关键词 acoustic scale effects acoustic boundary effects SIMILITUDE
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SERVICE COMMUNITY CONSTRUCTION METHOD OF INTERNET OF THINGS BASED ON SEMANTIC SIMILARITY 被引量:1
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作者 Wang Yang Zhang Linjing +2 位作者 Huang Yakun Zhao Baohua Zhao Chuanxin 《Journal of Electronics(China)》 2013年第1期49-56,共8页
Internet of Things (IoT) as an important and ubiquitous service paradigm is one of the most important issues in IoT applications to provide terminal users with effective and efficient services based on service communi... Internet of Things (IoT) as an important and ubiquitous service paradigm is one of the most important issues in IoT applications to provide terminal users with effective and efficient services based on service community. This paper presents a semantic-based similarity algorithm to build the IoT service community. Firstly, the algorithm reflects that the nodes of IoT contain a wealth of semantic information and makes them to build into the concept tree. Then tap the similarity of the semantic information based on the concept tree. Finally, we achieve the optimization of the service community through greedy algorithm and control the size of the service community by adjusting the threshold. Simulation results show the effectiveness and feasibility of this algorithm. 展开更多
关键词 Internet of Things (IoT) Service community Semantic similarity Concept tree
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Similarity measure design and similarity computation for discrete fuzzy data 被引量:7
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作者 LEE Sang-Hyuk PARK Wook-Je JUNG Dong-yean 《Journal of Central South University》 SCIE EI CAS 2011年第5期1602-1608,共7页
The similarity computations for fuzzy membership function pairs were carried out.Fuzzy number related knowledge was introduced,and conventional similarity was compared with distance based similarity measure.The useful... The similarity computations for fuzzy membership function pairs were carried out.Fuzzy number related knowledge was introduced,and conventional similarity was compared with distance based similarity measure.The usefulness of the proposed similarity measure was verified.The results show that the proposed similarity measure could be applied to ordinary fuzzy membership functions,though it was not easy to design.Through conventional results on the calculation of similarity for fuzzy membership pair,fuzzy membership-crisp pair and crisp-crisp pair were carried out.The proposed distance based similarity measure represented rational performance with the heuristic point of view.Furthermore,troublesome in fuzzy number based similarity measure for abnormal universe of discourse case was discussed.Finally,the similarity measure computation for various membership function pairs was discussed with other conventional results. 展开更多
关键词 similarity measure fuzzy number DISTANCE similarity evaluation fuzzy membership function
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Similarity measure application to fault detection of flight system 被引量:5
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作者 KIM J +4 位作者 H LEE S H 王洪梅 《Journal of Central South University》 SCIE EI CAS 2009年第5期789-793,共5页
Fault detection technique is introduced with similarity measure. The characteristics of conventional similarity measure based on fuzzy number are discussed. With the help of distance measure, similarity measure is con... Fault detection technique is introduced with similarity measure. The characteristics of conventional similarity measure based on fuzzy number are discussed. With the help of distance measure, similarity measure is constructed explicitly. The designed distance-based similarity measure is applicable to general fuzzy membership functions including non-convex fuzzy membership function, whereas fuzzy number-based similarity measure has limitation to calculate the similarity of general fuzzy membership functions. The applicability of the proposed similarity measure to general fuzzy membership structures is proven by identifying the definition. To decide fault detection of flight system, the experimental data (pitching moment coefficients and lift coefficients) are transformed into fuzzy membership functions. Distance-based similarity measure is applied to the obtained fuzzy membership functions, and similarity computation and analysis are obtained with the fault and normal operation coefficients. 展开更多
关键词 similarity measure fuzzy number distance non-convex membership function
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Hybrid scheduling model and analysis of performance for switched industrial Ethernet 被引量:1
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作者 胡春华 吴敏 +1 位作者 刘国平 王四春 《Journal of Central South University of Technology》 EI 2007年第2期271-277,共7页
The fact that outburst traffic in industrial Ethemet was focused on that would bring self-similar phenomenon leading to the delay increase of the cyclical data, and a hybrid priority queue schedule model was proposed ... The fact that outburst traffic in industrial Ethemet was focused on that would bring self-similar phenomenon leading to the delay increase of the cyclical data, and a hybrid priority queue schedule model was proposed in which the outburst data was given the highest priority. Some properties of the self-similar outburst data were proved by network calculus, and its service curve scheduled by the switch was gained. And then the performance of the scheduling algorithm was obtained. The simulation results are close to those calculated by using network calculus model. Some results are of actual significance to the construction of switched industrial Ethernet. 展开更多
关键词 switched industrial Ethemet scheduling model SELF-SIMILAR network calculus
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带层次网络结构的业务系统层次组织结构发现
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作者 熊永芳 林友芳 武志昊 《计算机与现代化》 2019年第7期88-96,共9页
业务系统架构图是运维人员维护数据中心的重要工具之一,自动化架构梳理能显著提高运维效率。业务系统架构图是一种具有层次网络的结构,因此对于这种层次组织结构发现问题,不仅需要发现集群分组还需要定位集群在系统架构图中的层次位置,... 业务系统架构图是运维人员维护数据中心的重要工具之一,自动化架构梳理能显著提高运维效率。业务系统架构图是一种具有层次网络的结构,因此对于这种层次组织结构发现问题,不仅需要发现集群分组还需要定位集群在系统架构图中的层次位置,因为集群分组发现的质量直接影响到集群层次定位,因此精准的集群分组发现至关重要。社区发现有助于揭示复杂网络结构中个体相互之间的关系,但业务系统中的服务器集群不符合传统社区基于密度的社区定义,因此本文提出一种根据服务器的功能进行集群发现并定位集群层级的功能集群定位方法(Functional Cluster Positioning,FCP),根据服务器连接、属性相似性,构建服务器相似度网络,该网络体现出的集群特性符合传统社区的定义,因此可以借助传统社区的方法进行集群分组发现,然后基于业务流势确定服务器集群在业务系统中的功能层次,从而实现业务系统层次组织结构发现。在真实数据集上的实验结果表明,本文提出的FCP方法在数据中心的业务系统中可以自动、准确发现系统的层次组织结构。 展开更多
关键词 系统架构图 层次网络 相似 社区发现
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An Alternative-Service Recommending Algorithm Based on Semantic Similarity 被引量:2
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作者 Kun Guo Yonghua Li Yueming Lu 《China Communications》 SCIE CSCD 2017年第8期124-136,共13页
With the development of the Internet of Things(Io T), people's lives have become increasingly convenient. It is desirable for smart home(SH) systems to integrate and leverage the enormous information available fro... With the development of the Internet of Things(Io T), people's lives have become increasingly convenient. It is desirable for smart home(SH) systems to integrate and leverage the enormous information available from IoT. Information can be analyzed to learn user intentions and automatically provide the appropriate services. However, existing service recommendation models typically do not consider the services that are unavailable in a user's living environment. In order to address this problem, we propose a series of semantic models for SH devices. These semantic models can be used to infer user intentions. Based on the models, we proposed a service recommendation probability model and an alternative-service recommending algorithm. The algorithm is devoted to providing appropriate alternative services when the desired service is unavailable. The algorithm has been implemented and achieves accuracy higher than traditional Hidden Markov Model(HMM). The maximum accuracy achieved is 68.3%. 展开更多
关键词 activity recognition semantic model service recommendation unavailable service
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