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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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Combination method of conflict evidences based on evidence similarity 被引量:10
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作者 Wenhao Bi An Zhang Yuan Yuan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第3期503-513,共11页
Aiming at the problem that the traditional Dempster Shafer (D-S) evidence theory cannot deal with conflicted evidences effectively and correctly, this paper points out that the key issue of this problem is to measure ... Aiming at the problem that the traditional Dempster Shafer (D-S) evidence theory cannot deal with conflicted evidences effectively and correctly, this paper points out that the key issue of this problem is to measure the degree of conflict between evidences correctly after analyzing various improved methods. The existing evidence conflict measure methods are analyzed, and a new evidence conflict measure method called evidence similarity measure based on the Tanimoto measure is proposed, while a new evidence combination method is proposed on the basis of evidence similarity measure. Firstly, the conflict degrees between evidences are obtained through the evidence similarity measure. Then the evidence sources are modified based on the credibility of different evidences and the weights of conflicted parts of evidences on different focal elements are determined. Finally, the fusion result is obtained by this method. Numerical examples show that the proposed method can effectively fuse evidences when evidences are consistent or highly conflicted, and it has a fast convergence speed, a high degree of accuracy and good adaptability. 展开更多
关键词 evidence theory evidence conflict conflict measure evidence similarity information fusion
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TAR~*:an improved process similarity measure based on unfolding of Petri nets 被引量:4
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作者 WANG Wen-xing WANG Jian-min 《计算机集成制造系统》 EI CSCD 北大核心 2012年第8期1774-1784,共11页
Determining the similarity degree between process models was very important for their management,reuse,and analysis.Current approaches either focused on process model's structural aspect,or had inefficiency or imp... Determining the similarity degree between process models was very important for their management,reuse,and analysis.Current approaches either focused on process model's structural aspect,or had inefficiency or imprecision in behavioral similarity.Aiming at these problems,a novel similarity measure which extended an existing method named Transition Adjacent Relation(TAR) with improved precision and efficiency named TAR * was proposed.The ability of measuring similarity was extended by eliminating the duplicate tasks without impacting the behaviors.For precision,TARs was classified into repeatable and unrepeatable ones to identify whether a TAR was involved in a loop.Two new kinds of TARs were added,one related to the invisible tasks after the source place and before sink place,and the other representing implicit dependencies.For efficiency,all TARs based on unfolding instead of its reach ability graph of a labeled Petri net were calculated to avoid state space explosion.Experiments on artificial and real-world process models showed the effectiveness and efficiency of the proposed method. 展开更多
关键词 transition adjacent relation UNFOLDING Petri nets behavioral similarity
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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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Design of ontology mapping framework and improvement of similarity computation 被引量:2
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作者 Zheng Liping Li Guangyao +1 位作者 Liang Yongquan Sha Jing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期641-645,共5页
Ontology heterogeneity is the primary obstacle for interoperation of ontologies. Ontology mapping is the best way to solve this problem. The key of ontology mapping is the similarity computation. At present, the metho... Ontology heterogeneity is the primary obstacle for interoperation of ontologies. Ontology mapping is the best way to solve this problem. The key of ontology mapping is the similarity computation. At present, the method of similarity computation is imperfect. And the computation quantity is high. To solve these problems, an ontology-mapping framework with a kind of hybrid architecture is put forward, with an improvement in the method of similarity computation. Different areas have different local ontologies. Two ontologies are taken as examples, to explain the specific mapping framework and improved method of similarity computation. These two ontologies are about classes and teachers in a university. The experimental results show that using this framework and improved method can increase the accuracy of computation to a certain extent. Otherwise, the quantity of computation can be decreased. 展开更多
关键词 ONTOLOGY ontology heterogeneity ontology mapping WORDNET similarity computation.
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Novel antenna selection algorithm based on Tanimoto similarity 被引量:2
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作者 Yang Haifen Li Guangjun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第3期624-627,共4页
A new antenna selection algorithm for multiple input multiple output (MIMO) wireless systems is proposed. The modified Tanimoto coefficient is used to compare the similarity of the rows/columns of the channel matrix... A new antenna selection algorithm for multiple input multiple output (MIMO) wireless systems is proposed. The modified Tanimoto coefficient is used to compare the similarity of the rows/columns of the channel matrix. Based on the calculated similarity, the proposed algorithm chooses the antenna subset, which has the maximum product of dissimilarity and Frobenius norm. The proposed algorithm requires low computational complexity as to the optimal selection but with comparative outage capacity and average signal to noise ratio (SNR) performance. It can improve both the outage capacity and the average SNR as compared to random selection. The simulation results are shown to validate our algorithm. 展开更多
关键词 MIMO system antenna selection Tanimoto similarity outage capacity.
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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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Quantitative similarity assessment of non-linear chemical fingerprint of traditional Chinese medicine by similarity system theory 被引量:5
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作者 周菊峰 方宣启 +4 位作者 张泰铭 赵哲 朱蓉 向凤琴 乔君喜 《Journal of Central South University》 SCIE EI CAS 2011年第2期343-352,共10页
The similarities of the non-linear chemical (NLC) fingerprints of Radix Glycyrrhizaes from four producing areas and eight other traditional Chinese medicines (TCMs) were calculated, using a systemic similarity cal... The similarities of the non-linear chemical (NLC) fingerprints of Radix Glycyrrhizaes from four producing areas and eight other traditional Chinese medicines (TCMs) were calculated, using a systemic similarity calculation method proposed and three other main calculation ones (Euclidean distance, correlation coefficient and included angle cosine). All of the correlation coefficient similarities of different TCMs are higher than 0.952, and the included angle cosines are all higher than 0.962. So, both the conelation coefficient and included angle cosine similarities are unable to be used as the criteria for quantitatively evaluating the similarities of NLC fingerprints of TCMs. Although all of the Euclidean distance similarities of Berry Liquorices from four producing areas are less than 73, those of the other eight TCMs are all more than 180. The Euclidean distance cannot reflect the relative magnitudes of the feature differences in the NLC fingerprints very correctly. The systemic similarity method is the best among the four ones. All of the systemic similarities of Berry Liquorices from the four producing areas are higher than 0.962, while those of the other eight TCMs are all lower than 0.805, and the systemic similarity can reflect the differences between samples most faithfully, and can be used as a quantitative one evaluating the similarities of NLC fingerprints of TCMs, by which TCM could be distinguished and evaluated quickly, simply and exactly. 展开更多
关键词 nonlinear chemistry fingerprint systemic similarity traditional Chinese medicine
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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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Similarity measure design for high dimensional data 被引量:3
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作者 LEE Sang-hyuk YAN Sun +1 位作者 JEONG Yoon-su SHIN Seung-soo 《Journal of Central South University》 SCIE EI CAS 2014年第9期3534-3540,共7页
Information analysis of high dimensional data was carried out through similarity measure application. High dimensional data were considered as the a typical structure. Additionally, overlapped and non-overlapped data ... Information analysis of high dimensional data was carried out through similarity measure application. High dimensional data were considered as the a typical structure. Additionally, overlapped and non-overlapped data were introduced, and similarity measure analysis was also illustrated and compared with conventional similarity measure. As a result, overlapped data comparison was possible to present similarity with conventional similarity measure. Non-overlapped data similarity analysis provided the clue to solve the similarity of high dimensional data. Considering high dimensional data analysis was designed with consideration of neighborhoods information. Conservative and strict solutions were proposed. Proposed similarity measure was applied to express financial fraud among multi dimensional datasets. In illustrative example, financial fraud similarity with respect to age, gender, qualification and job was presented. And with the proposed similarity measure, high dimensional personal data were calculated to evaluate how similar to the financial fraud. Calculation results show that the actual fraud has rather high similarity measure compared to the average, from minimal 0.0609 to maximal 0.1667. 展开更多
关键词 high dimensional data similarity measure DIFFERENCE neighborhood information financial fraud
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Wavelet matrix transform for time-series similarity measurement 被引量:2
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作者 胡志坤 徐飞 +1 位作者 桂卫华 阳春华 《Journal of Central South University》 SCIE EI CAS 2009年第5期802-806,共5页
A time-series similarity measurement method based on wavelet and matrix transform was proposed,and its anti-noise ability,sensitivity and accuracy were discussed. The time-series sequences were compressed into wavelet... A time-series similarity measurement method based on wavelet and matrix transform was proposed,and its anti-noise ability,sensitivity and accuracy were discussed. The time-series sequences were compressed into wavelet subspace,and sample feature vector and orthogonal basics of sample time-series sequences were obtained by K-L transform. Then the inner product transform was carried out to project analyzed time-series sequence into orthogonal basics to gain analyzed feature vectors. The similarity was calculated between sample feature vector and analyzed feature vector by the Euclid distance. Taking fault wave of power electronic devices for example,the experimental results show that the proposed method has low dimension of feature vector,the anti-noise ability of proposed method is 30 times as large as that of plain wavelet method,the sensitivity of proposed method is 1/3 as large as that of plain wavelet method,and the accuracy of proposed method is higher than that of the wavelet singular value decomposition method. The proposed method can be applied in similarity matching and indexing for lager time series databases. 展开更多
关键词 wavelet transform singular value decomposition inner product transform time-series similarity
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Improved similarity criterion for seepage erosion using mesoscopic coupled PFC–CFD model 被引量:3
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作者 倪小东 王媛 +1 位作者 陈珂 赵帅龙 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期3069-3078,共10页
Conventional model tests and centrifuge tests are frequently used to investigate seepage erosion. However, the centrifugal test method may not be efficient according to the results of hydraulic conductivity tests and ... Conventional model tests and centrifuge tests are frequently used to investigate seepage erosion. However, the centrifugal test method may not be efficient according to the results of hydraulic conductivity tests and piping erosion tests. The reason why seepage deformation in model tests may deviate from similarity was first discussed in this work. Then, the similarity criterion for seepage deformation in porous media was improved based on the extended Darcy-Brinkman-Forchheimer equation. Finally, the coupled particle flow code–computational fluid dynamics(PFC-CFD) model at the mesoscopic level was proposed to verify the derived similarity criterion. The proposed model maximizes its potential to simulate seepage erosion via the discrete element method and satisfy the similarity criterion by adjusting particle size. The numerical simulations achieved identical results with the prototype, thus indicating that the PFC-CFD model that satisfies the improved similarity criterion can accurately reproduce the processes of seepage erosion at the mesoscopic level. 展开更多
关键词 mesoscopic model centrifugal model similarity criterion particle flow code-computational fluid dynamics (PFC-CFD)
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Near-duplicate document detection with improved similarity measurement 被引量:2
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作者 袁鑫攀 龙军 +1 位作者 张祖平 桂卫华 《Journal of Central South University》 SCIE EI CAS 2012年第8期2231-2237,共7页
To quickly find documents with high similarity in existing documentation sets, fingerprint group merging retrieval algorithm is proposed to address both sides of the problem:a given similarity threshold could not be t... To quickly find documents with high similarity in existing documentation sets, fingerprint group merging retrieval algorithm is proposed to address both sides of the problem:a given similarity threshold could not be too low and fewer fingerprints could lead to low accuracy. It can be proved that the efficiency of similarity retrieval is improved by fingerprint group merging retrieval algorithm with lower similarity threshold. Experiments with the lower similarity threshold r=0.7 and high fingerprint bits k=400 demonstrate that the CPU time-consuming cost decreases from 1 921 s to 273 s. Theoretical analysis and experimental results verify the effectiveness of this method. 展开更多
关键词 similarity estimation near-duplicate document detection fingerprint group Hamming distance minwise hashing
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Design of similarity measure for discrete data and application to multi-dimension 被引量:1
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作者 LEE Myeong-ho 魏荷 +2 位作者 LEE Sang-hyuk LEE Sang-min SHIN Seung-soo 《Journal of Central South University》 SCIE EI CAS 2013年第4期982-987,共6页
Similarity measure design for discrete data group was proposed. Similarity measure design for continuous membership function was also carried out. Proposed similarity measures were designed based on fuzzy number and d... Similarity measure design for discrete data group was proposed. Similarity measure design for continuous membership function was also carried out. Proposed similarity measures were designed based on fuzzy number and distance measure, and were proved. To calculate the degree of similarity of discrete data, relative degree between data and total distribution was obtained. Discrete data similarity measure was completed with combination of mentioned relative degrees. Power interconnected system with multi characteristics was considered to apply discrete similarity measure. Naturally, similarity measure was extended to multi-dimensional similarity measure case, and applied to bus clustering problem. 展开更多
关键词 similarity measure MULTI-DIMENSION discrete data relative degree power interconnected system
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Designing similarity measurement with distance measure and application on laterally directional mode flight test 被引量:1
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作者 PARK Wook-je LEE Sang-min LEE Sang-hyuk 《Journal of Central South University》 SCIE EI CAS 2012年第4期1032-1039,共8页
Similarity measure construction has been proposed as fault detection of flight test method in order to obtain the primary control surface stuck and the combination stuck of primary control.Similarity measures were obt... Similarity measure construction has been proposed as fault detection of flight test method in order to obtain the primary control surface stuck and the combination stuck of primary control.Similarity measures were obtained through analyzing the certainty and uncertainty of fuzzy membership functions,which were designed based on well-known Hamming distance.It was applied to the fault detection of primary control surface stuck of uninhabited aerial vehicle(UAV).At post-failure control surface,if the UAV is controllable and trimmable using other control surfaces,the UAV is able to fly or return to the safety region through reconfiguration of flight control system.To detect the fault,similarity measure computations were carried out.This result could be applicable with the real-time parameter estimation method.By monitoring the value of coefficients due to the control surface deviation,it becomes aware that the control surface fault occurs or not.The control surface stuck position and value were separated by comparing the trim value with the reference value.This is the advantage of increasing in reliability without adding sensors or with additional low cost. 展开更多
关键词 similarity measure fault detection and isolation real-time parameter estimation control surface stuck
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Static rough similarity degree and its applications
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作者 Xu Xiaojing Li Jian Shi Kaiquan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第2期311-315,共5页
The definition of rough similarity degree is given based on the axiomatic similarity degree, and the properties of rough similarity degree are listed. Using the properties of rough similarity degree, the method of clu... The definition of rough similarity degree is given based on the axiomatic similarity degree, and the properties of rough similarity degree are listed. Using the properties of rough similarity degree, the method of clustering in rough systems can be obtained. After clustering, a new sample can be recognized by the principle of maximal rough similarity degree. 展开更多
关键词 rough similarity degree CLUSTERING recognition of rough pattern maximal similarity degree principle.
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Rough similarity degree and rough close degree in rough fuzzy sets and the applications
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作者 Li Jian Xu Xiaojing Shi Kaiquan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第5期945-951,共7页
Based on rough similarity degree of rough sets and close degree of fuzzy sets, the definitions of rough similarity degree and rough close degree of rough fuzzy sets are given, which can be used to measure the similar ... Based on rough similarity degree of rough sets and close degree of fuzzy sets, the definitions of rough similarity degree and rough close degree of rough fuzzy sets are given, which can be used to measure the similar degree between two rough fuzzy sets. The properties and theorems are listed. Using the two new measures, the method of clustering in the rough fuzzy system can be obtained. After clustering, the new fuzzy sample can be recognized by the principle of maximal similarity degree. 展开更多
关键词 rough fuzzy set rough similarity degree rough close degree CLUSTERING recognition of rough pattern maximal similarity degree principle.
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The Application of Similarity Theory in Designing Large Deflection Buckling Spring-Piece
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作者 Huang Tiequn Jia Shushi Sun Yueming Cheng Yaodong 《上海交通大学学报》 EI CAS CSCD 北大核心 2004年第z2期42-47,共6页
Large Deflection Buckling Spring-Piece (LDBSP) refers to the deformation of an end-fixed flat spring-piece under normal loadings. Plastic deformation usually appears in LDBSP.The static characteristic curve is very pa... Large Deflection Buckling Spring-Piece (LDBSP) refers to the deformation of an end-fixed flat spring-piece under normal loadings. Plastic deformation usually appears in LDBSP.The static characteristic curve is very particular, because within its linear deflection region, the spring constant can be designed to be any value from minus to plus. With its obvious advantages of large liner deflection range, low spring constant, etc., the LDBSP has now been extensively applied to the exciting device, low-frequency shock absorbers and so on. The static characteristic curve of LDBSP belongs to the nonlinear problem of an arch with varying section. Therefore, it is difficult to obtain it theoretically. The formulae for designing LDBSP have not been set up yet. In this study,the authors apply similarity theory to analyze the liner deflection range A and the spring constant K, and derive the relationship of similarity criterion, finally obtain a set of formulae for designing LDBSP by model test and the least square method, which can be applied in engineering design.Through the research, it is proved that it is unnecessary to keep geometrical similarity of spring-piece shape. This fact extends the application scope of the formulae. The proposed formulae for designing LDBSP thereby can be applied for any dimensions within the range allowed. 展开更多
关键词 similarity theory similarity CRITERION dimension model test DEFLECTION SPRING SPRING constant plastic deformation
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Circuit Compression Based on Similarity for RTL ATPG
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作者 Ji Chen Jishun Kuang Dafang Zhang 《湖南大学学报(自然科学版)》 EI CAS CSCD 2000年第S2期78-85,共8页
This paper analyzes structural characteristics of signal vectors in combinational circuits with RTL description. Then, this paper presents the concept of the Basic Similar Circuit (BSC), a circuit constructed by compr... This paper analyzes structural characteristics of signal vectors in combinational circuits with RTL description. Then, this paper presents the concept of the Basic Similar Circuit (BSC), a circuit constructed by compressing the bit-width of vectored vectors in the original circuit. BSC shrinks the scale of the original circuit, thus improving the ATPG efficiency. Test patterns are derived from adjustment and assembling of precomputed sub-circuit test sets. Based on the deterministic algorithm, the ATPG method presented in this paper combines deterministic algorithms and undetermined methods. 展开更多
关键词 RTL combinational circuit similar circuit BSC VECTOR similar mapping ATPG
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