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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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Research and Implementation of Text Similarity System Based on Power Spectrum Analysis 被引量:1
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作者 Ying Xie Shouning Qu Huanhuan Song 《Journal of Computer and Communications》 2014年第6期7-17,共11页
The paper proposed the research and implement of text similarity system based on power spectrum analysis. It is not difficult to imagine that the signals of brain are closely linked with writing process. So we build t... The paper proposed the research and implement of text similarity system based on power spectrum analysis. It is not difficult to imagine that the signals of brain are closely linked with writing process. So we build text modeling and set pulse signal function to get the power spectrum of the text. The specific detail is getting power spectrum from economic field to build spectral library, and then using the method of power spectrum matching algorithm to judge whether the test text belonged to the economic field. The method made text similarity system finish the function of text intelligent classification efficiently and accurately. 展开更多
关键词 Pulsing Signal Function Power Spectrum MATCHING Algorithm TEXT similarity system TEXT Intelligent Classification
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Multimodal Social Media Fake News Detection Based on Similarity Inference and Adversarial Networks 被引量:1
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作者 Fangfang Shan Huifang Sun Mengyi Wang 《Computers, Materials & Continua》 SCIE EI 2024年第4期581-605,共25页
As social networks become increasingly complex, contemporary fake news often includes textual descriptionsof events accompanied by corresponding images or videos. Fake news in multiple modalities is more likely tocrea... As social networks become increasingly complex, contemporary fake news often includes textual descriptionsof events accompanied by corresponding images or videos. Fake news in multiple modalities is more likely tocreate a misleading perception among users. While early research primarily focused on text-based features forfake news detection mechanisms, there has been relatively limited exploration of learning shared representationsin multimodal (text and visual) contexts. To address these limitations, this paper introduces a multimodal modelfor detecting fake news, which relies on similarity reasoning and adversarial networks. The model employsBidirectional Encoder Representation from Transformers (BERT) and Text Convolutional Neural Network (Text-CNN) for extracting textual features while utilizing the pre-trained Visual Geometry Group 19-layer (VGG-19) toextract visual features. Subsequently, the model establishes similarity representations between the textual featuresextracted by Text-CNN and visual features through similarity learning and reasoning. Finally, these features arefused to enhance the accuracy of fake news detection, and adversarial networks have been employed to investigatethe relationship between fake news and events. This paper validates the proposed model using publicly availablemultimodal datasets from Weibo and Twitter. Experimental results demonstrate that our proposed approachachieves superior performance on Twitter, with an accuracy of 86%, surpassing traditional unimodalmodalmodelsand existing multimodal models. In contrast, the overall better performance of our model on the Weibo datasetsurpasses the benchmark models across multiple metrics. The application of similarity reasoning and adversarialnetworks in multimodal fake news detection significantly enhances detection effectiveness in this paper. However,current research is limited to the fusion of only text and image modalities. Future research directions should aimto further integrate features fromadditionalmodalities to comprehensively represent themultifaceted informationof fake news. 展开更多
关键词 Fake news detection attention mechanism image-text similarity multimodal feature fusion
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Similarity matching method of power distribution system operating data based on neural information retrieval
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作者 Kai Xiao Daoxing Li +2 位作者 Pengtian Guo Xiaohui Wang Yong Chen 《Global Energy Interconnection》 EI CAS CSCD 2023年第1期15-25,共11页
Operation control of power systems has become challenging with an increase in the scale and complexity of power distribution systems and extensive access to renewable energy.Therefore,improvement of the ability of dat... Operation control of power systems has become challenging with an increase in the scale and complexity of power distribution systems and extensive access to renewable energy.Therefore,improvement of the ability of data-driven operation management,intelligent analysis,and mining is urgently required.To investigate and explore similar regularities of the historical operating section of the power distribution system and assist the power grid in obtaining high-value historical operation,maintenance experience,and knowledge by rule and line,a neural information retrieval model with an attention mechanism is proposed based on graph data computing technology.Based on the processing flow of the operating data of the power distribution system,a technical framework of neural information retrieval is established.Combined with the natural graph characteristics of the power distribution system,a unified graph data structure and a data fusion method of data access,data complement,and multi-source data are constructed.Further,a graph node feature-embedding representation learning algorithm and a neural information retrieval algorithm model are constructed.The neural information retrieval algorithm model is trained and tested using the generated graph node feature representation vector set.The model is verified on the operating section of the power distribution system of a provincial grid area.The results show that the proposed method demonstrates high accuracy in the similarity matching of historical operation characteristics and effectively supports intelligent fault diagnosis and elimination in power distribution systems. 展开更多
关键词 Neural information retrieval Power distribution Graph data Operating section similarity matching
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Attribute Reduction for Information Systems via Strength of Rules and Similarity Matrix
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作者 Mohsen Eid Tamer Medhat Manal E.Ali 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期1531-1544,共14页
An information system is a type of knowledge representation,and attribute reduction is crucial in big data,machine learning,data mining,and intelligent systems.There are several ways for solving attribute reduction pr... An information system is a type of knowledge representation,and attribute reduction is crucial in big data,machine learning,data mining,and intelligent systems.There are several ways for solving attribute reduction problems,but they all require a common categorization.The selection of features in most scientific studies is a challenge for the researcher.When working with huge datasets,selecting all available attributes is not an option because it frequently complicates the study and decreases performance.On the other side,neglecting some attributes might jeopardize data accuracy.In this case,rough set theory provides a useful approach for identifying superfluous attributes that may be ignored without sacrificing any significant information;nonetheless,investigating all available combinations of attributes will result in some problems.Furthermore,because attribute reduction is primarily a mathematical issue,technical progress in reduction is dependent on the advancement of mathematical models.Because the focus of this study is on the mathematical side of attribute reduction,we propose some methods to make a reduction for information systems according to classical rough set theory,the strength of rules and similarity matrix,we applied our proposed methods to several examples and calculate the reduction for each case.These methods expand the options of attribute reductions for researchers. 展开更多
关键词 Rough set REDUCTION strength of rules similarity matrix
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Investigation on mechanical properties regulation of rock-like specimens based on 3D printing and similarity quantification
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作者 Duanyang Zhuang Zexu Ning +3 位作者 Yunmin Chen Jinlong Li Qingdong Li Wenjie Xu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第5期573-585,共13页
3D printing is widely adopted to quickly produce rock mass models with complex structures in batches,improving the consistency and repeatability of physical modeling.It is necessary to regulate the mechanical properti... 3D printing is widely adopted to quickly produce rock mass models with complex structures in batches,improving the consistency and repeatability of physical modeling.It is necessary to regulate the mechanical properties of 3D-printed specimens to make them proportionally similar to natural rocks.This study investigates mechanical properties of 3D-printed rock analogues prepared by furan resin-bonded silica sand particles.The mechanical property regulation of 3D-printed specimens is realized through quantifying its similarity to sandstone,so that analogous deformation characteristics and failure mode are acquired.Considering similarity conversion,uniaxial compressive strength,cohesion and stress–strain relationship curve of 3D-printed specimen are similar to those of sandstone.In the study ranges,the strength of 3D-printed specimen is positively correlated with the additive content,negatively correlated with the sand particle size,and first increases then decreases with the increase of curing temperature.The regulation scheme with optimal similarity quantification index,that is the sand type of 70/140,additive content of 2.5‰and curing temperature of 81.6℃,is determined for preparing 3D-printed sandstone analogues and models.The effectiveness of mechanical property regulation is proved through uniaxial compression contrast tests.This study provides a reference for preparing rock-like specimens and engineering models using 3D printing technology. 展开更多
关键词 3D printing Mechanical property regulation similarity quantification Rock analogue SANDSTONE
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A Non-Parametric Scheme for Identifying Data Characteristic Based on Curve Similarity Matching
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作者 Quanbo Ge Yang Cheng +3 位作者 Hong Li Ziyi Ye Yi Zhu Gang Yao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1424-1437,共14页
For accurately identifying the distribution charac-teristic of Gaussian-like noises in unmanned aerial vehicle(UAV)state estimation,this paper proposes a non-parametric scheme based on curve similarity matching.In the... For accurately identifying the distribution charac-teristic of Gaussian-like noises in unmanned aerial vehicle(UAV)state estimation,this paper proposes a non-parametric scheme based on curve similarity matching.In the framework of the pro-posed scheme,a Parzen window(kernel density estimation,KDE)method on sliding window technology is applied for roughly esti-mating the sample probability density,a precise data probability density function(PDF)model is constructed with the least square method on K-fold cross validation,and the testing result based on evaluation method is obtained based on some data characteristic analyses of curve shape,abruptness and symmetry.Some com-parison simulations with classical methods and UAV flight exper-iment shows that the proposed scheme has higher recognition accuracy than classical methods for some kinds of Gaussian-like data,which provides better reference for the design of Kalman filter(KF)in complex water environment. 展开更多
关键词 Curve similarity matching Gaussian-like noise non-parametric scheme parzen window.
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Numerical Simulation of the Settling Flux of Biodeposition in a Bay with Cage Culture Through Similarity Theory and a Simplified Pollution Source
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作者 LIU Yao CHEN Yifan GE Changzi 《Journal of Ocean University of China》 CAS CSCD 2024年第1期247-254,共8页
The settling flux of biodeposition affects the environmental quality of cage culture areas and determines their environmental carrying capacity.Simple and effective simulation of the settling flux of biodeposition is ... The settling flux of biodeposition affects the environmental quality of cage culture areas and determines their environmental carrying capacity.Simple and effective simulation of the settling flux of biodeposition is extremely important for determining the spatial distribution of biodeposition.Theoretically,biodeposition in cage culture areas without specific emission rules can be simplified as point source pollution.Fluent is a fluid simulation software that can simulate the dispersion of particulate matter simply and efficiently.Based on the simplification of pollution sources and bays,the settling flux of biodeposition can be easily and effectively simulated by Fluent fluid software.In the present work,the feasibility of this method was evaluated by simulation of the settling flux of biodeposition in Maniao Bay,Hainan Province,China,and 20 sampling sites were selected for determining the settling fluxes.At sampling sites P1,P2,P3,P4,P5,Z1,Z2,Z3,Z4,A1,A2,A3,A4,B1,B2,C1,C2,C3 and C4,the measured settling fluxes of biodeposition were 26.02,15.78,10.77,58.16,6.57,72.17,12.37,12.11,106.64,150.96,22.59,11.41,18.03,7.90,19.23,7.06,11.84,5.19 and 2.57 g d^(−1)m^(−2),respectively.The simulated settling fluxes of biodeposition at the corresponding sites were 16.03,23.98,8.87,46.90,4.52,104.77,16.03,8.35,180.83,213.06,39.10,17.47,20.98,9.78,23.25,7.84,15.90,6.06 and 1.65 g d^(−1)m^(−2),respectively.There was a positive correlation between the simulated settling fluxes and measured ones(R=0.94,P=2.22×10^(−9)<0.05),which implies that the spatial differentiation of biodeposition flux was well simulated.Moreover,the posterior difference ratio of the simulation was 0.38,and the small error probability was 0.94,which means that the simulated results reached an acceptable level from the perspective of relative error.Thus,if nonpoint source pollution is simplified to point source pollution and open waters are simplified based on similarity theory,the setting flux of biodeposition in the open waters can be simply and effectively simulated by the fluid simulation software Fluent. 展开更多
关键词 fluent fluid simulation software pollution source simplification posterior difference ratio similarity theory Spear-man correlation
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Structural similarity of lithospheric velocity models of Chinese mainland
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作者 Feng Huang Xueyang Bao +1 位作者 Qili Andy Dai Xinfu Li 《Earthquake Science》 2024年第6期514-528,共15页
Existing lithospheric velocity models exhibit similar structures typically associated with the first-order tectonic features,with dissimilarities due to different data and methods used in model generation.The quantifi... Existing lithospheric velocity models exhibit similar structures typically associated with the first-order tectonic features,with dissimilarities due to different data and methods used in model generation.The quantification of model structural similarity can help in interpreting the geophysical properties of Earth's interior and establishing unified models crucial in natural hazard assessment and resource exploration.Here we employ the complex wavelet structural similarity index measure(CW-SSIM)active in computer image processing to analyze the structural similarity of four lithospheric velocity models of Chinese mainland published in the past decade.We take advantage of this method in its multiscale definition and insensitivity to slight geometrical distortion like translation and scaling,which is particularly crucial in the structural similarity analysis of velocity models accounting for uncertainty and resolution.Our results show that the CW-SSIM values vary in different model pairs,horizontal locations,and depths.While variations in the inter-model CW-SSIM are partly owing to different databases in the model generation,the difference of tomography methods may significantly impact the similar structural features of models,such as the low similarities between the full-wave based FWEA18 and other three models in northeastern China.We finally suggest potential solutions for the next generation of tomographic modeling in different areas according to corresponding structural similarities of existing models. 展开更多
关键词 structural similarity LITHOSPHERE TOMOGRAPHY velocity model Chinese mainland
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Similarity evaluation model for the internal defect detection of strip steel
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作者 ZHANG Yalin WANG Yaojie WANG Xuemin 《Baosteel Technical Research》 CAS 2024年第1期8-13,共6页
An internal defect meter is an instrument to detect the internal inclusion defects of cold-rolled strip steel.The detection accuracy of the equipment can be evaluated based on the similarity of the multiple detection ... An internal defect meter is an instrument to detect the internal inclusion defects of cold-rolled strip steel.The detection accuracy of the equipment can be evaluated based on the similarity of the multiple detection data obtained for the same steel coil.Based on the cosine similarity model and eigenvalue matrix model,a comprehensive evaluation method to calculate the weighted average of similarity is proposed.Results show that the new method is consistent with and can even replace artificial evaluation to realize the automatic evaluation of strip defect detection results. 展开更多
关键词 internal defect INCLUSION similarity evaluation model REPEATABILITY detection equipment strip steel
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A Development of a Knowledge Management System for Water Situation Reports in Thailand
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作者 Prattana Deeprasertkul 《Journal of Computer and Communications》 2024年第10期24-36,共13页
The development of a knowledge management system for the National Hydro Data Center of Thailand was described in this paper. The system was created after the major flood event in 2011 to improve water resource managem... The development of a knowledge management system for the National Hydro Data Center of Thailand was described in this paper. The system was created after the major flood event in 2011 to improve water resource management. It addresses the need for easy access to water situation reports, which are crucial for informed decision-making on water usage, allocation, and reservoir management. The system utilizes Optical Character Recognition technique to convert scanned water situation reports into searchable text. It applied FastText and ElasticSearch for advanced search functionalities. FastText identified the documents related to the search query, even with typos or misspelled words. ElasticSearch allows for efficient searching of text data based on relevance. The system also integrates Google Search for additional information access. Therefore, this knowledge management system provides an efficient way to access and analyze water situation data in Thailand. 展开更多
关键词 Optical Character Recognition Text similarity FastText ElasticSearch
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Some Concepts and Mathematical Consideration of Similarity System Theory 被引量:17
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作者 ZHOU MeiliDepartment of Mechanical Engineering, Anhui Institute of Technology 111 Lu An Road, Hefei 230069, the People’s Republic of China 《Systems Science and Systems Engineering》 CSCD 1992年第1期84-92,共9页
This paper introduces a new discipline called Similarity System Theory. Some new concepts, such as Similar Elements, Similarity Unit, Similar Systems and Similarity Entropy are presented. The numerical method and dyna... This paper introduces a new discipline called Similarity System Theory. Some new concepts, such as Similar Elements, Similarity Unit, Similar Systems and Similarity Entropy are presented. The numerical method and dynamic analysis of similarity system theory are studied. 展开更多
关键词 similar elements similar systems similarity entropy similarity measures.
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A New Fire Detection Method Using a Multi-Expert System Based on Color Dispersion, Similarity and Centroid Motion in Indoor Environment 被引量:8
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作者 Teng Wang Leping Bu +2 位作者 Zhikai Yang Peng Yuan Jineng Ouyang 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2020年第1期263-275,共13页
In this paper, a video fire detection method is proposed, which demonstrated good performance in indoor environment. Three main novel ideas have been introduced. Firstly, a flame color model in RGB and HIS color space... In this paper, a video fire detection method is proposed, which demonstrated good performance in indoor environment. Three main novel ideas have been introduced. Firstly, a flame color model in RGB and HIS color space is used to extract pre-detected regions instead of traditional motion differential method, as it’s more suitable for fire detection in indoor environment. Secondly, according to the flicker characteristic of the flame, similarity and two main values of centroid motion are proposed. At the same time, a simple but effective method for tracking the same regions in consecutive frames is established. Thirdly,a multi-expert system consisting of color component dispersion,similarity and centroid motion is established to identify flames.The proposed method has been tested on a very large dataset of fire videos acquired both in real indoor environment tests and from the Internet. The experimental results show that the proposed approach achieved a balance between the false positive rate and the false negative rate, and demonstrated a better performance in terms of overall accuracy and F standard with respect to other similar fire detection methods in indoor environment. 展开更多
关键词 Color dispersion centroid motion expert system RGB-HIS color model similarity video fire detection
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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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Modified (2+1)-dimensional displacement shallow water wave system and its approximate similarity solutions 被引量:4
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作者 刘萍 付培凯 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期30-36,共7页
Recently, a new (2+1)-dimensional shallow water wave system, the (2+1)-dlmenslonal displacement shallow water wave system (2DDSWWS), was constructed by applying the variational principle of the analytic mechan... Recently, a new (2+1)-dimensional shallow water wave system, the (2+1)-dlmenslonal displacement shallow water wave system (2DDSWWS), was constructed by applying the variational principle of the analytic mechanics in the Lagrange coordinates. The disadvantage is that fluid viscidity is not considered in the 2DDSWWS, which is the same as the famous Kadomtsev-Petviashvili equation and Korteweg-de Vries equation. Applying dimensional analysis, we modify the 2DDSWWS and add the term related to the fluid viscidity to the 2DDSWWS. The approximate similarity solutions of the modified 2DDSWWS (M2DDSWWS) is studied and four similarity solutions are obtained. For the perfect fluids, the coefficient of kinematic viscosity is zero, then the M2DDSWWS will degenerate to the 2DDSWWS. 展开更多
关键词 modified (2+1)-dimensional displacement shallow water wave system viscidity approx-imate similarity solutions Kadomtsev-Petviashvili equation
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Design and Implementation of FAQ Automatic Return System Based on Similarity Computation 被引量:2
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作者 ZHANG Liang CHEN Zhao-xiong HUANG He-yan 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期138-142,共5页
FAQ (frequently asked question) is widely used on the Internet, but most FAQ's asking and answering are not automatic. This paper introduces the design and imple mentation of a FAQ automatic return system based on ... FAQ (frequently asked question) is widely used on the Internet, but most FAQ's asking and answering are not automatic. This paper introduces the design and imple mentation of a FAQ automatic return system based on semantic similarity computation, including computation model choo sing, FAQ characters analyzing, FAQ data formal expressing, feature vector indexing, and weight computing and so on. According to FAQ features of sentence length short, two mapping, strong domain characteristics etc. Vector Space Model with special semantic process was selected in system, and corresponding algorithm of similarity computation was proposed too. Experiment shows that the system has a good performance for high frequent and common questions. 展开更多
关键词 FAQ VSM similarity computation information retrieval
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Profile and Rating Similarity Analysis for Recommendation Systems Using Deep Learning 被引量:2
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作者 Lakshmi Palaniappan K.Selvaraj 《Computer Systems Science & Engineering》 SCIE EI 2022年第6期903-917,共15页
Recommendation systems are going to be an integral part of any E-Business in near future.As in any other E-business,recommendation systems also play a key role in the travel business where the user has to be recommend... Recommendation systems are going to be an integral part of any E-Business in near future.As in any other E-business,recommendation systems also play a key role in the travel business where the user has to be recommended with a restaurant that best suits him.In general,the recommendations to a user are made based on similarity that exists between the intended user and the other users.This similarity can be calculated either based on the similarity between the user profiles or the similarity between the ratings made by the users.First phase of this work concentrates on experimentally analyzing both these models and get a deep insight of these models.With the lessons learned from the insights,second phase of the work concentrates on developing a deep learning model.The model does not depend on the other user's profile or rating made by them.The model is tested with a small restaurant dataset and the model can predict whether a user likes the restaurant or not.The model is trained with different users and their rating.The system learns from it and in order to predict whether a new user likes or not a restaurant that he/she has not visited earlier,all the data the trained model needed is the rating made by the same user for different restaurants.The model is deployed in a cloud environment in order to extend it to be more realistic product in future.Result evaluated with dataset,it achieves 74.6%is accurate prediction of results,where as existing techniques achieves only 64%. 展开更多
关键词 Deep learning restricted boltzman machine profile based similarity rating based similarity item based similarity
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Fuzzy-Weighted Similarity Measures for Memory-Based Collaborative Recommender Systems 被引量:4
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作者 Mohammad Yahya H. Al-Shamri Nagi H. Al-Ashwal 《Journal of Intelligent Learning Systems and Applications》 2014年第1期1-10,共10页
Memory-based collaborative recommender system (CRS) computes the similarity between users based on their declared ratings. However, not all ratings are of the same importance to the user. The set of ratings each user ... Memory-based collaborative recommender system (CRS) computes the similarity between users based on their declared ratings. However, not all ratings are of the same importance to the user. The set of ratings each user weights highly differs from user to user according to his mood and taste. This is usually reflected in the user’s rating scale. Accordingly, many efforts have been done to introduce weights to the similarity measures of CRSs. This paper proposes fuzzy weightings for the most common similarity measures for memory-based CRSs. Fuzzy weighting can be considered as a learning mechanism for capturing the preferences of users for ratings. Comparing with genetic algorithm learning, fuzzy weighting is fast, effective and does not require any more space. Moreover, fuzzy weightings based on the rating deviations from the user’s mean of ratings take into account the different rating scales of different users. The experimental results show that fuzzy weightings obviously improve the CRSs performance to a good extent. 展开更多
关键词 COLLABORATIVE RECOMMENDER systems Pearson Correlation Coefficient COSINE similarity MEASURE Mean Difference Weights similarity MEASURE FUZZY Weighting
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Effect of Two Kinds of Similarity Factors on Principal Component Analysis Fault Detection in Air Conditioning Systems 被引量:2
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作者 YANG Xuebin HE Ruru +1 位作者 WANG Ji LUO Wenjun 《Journal of Donghua University(English Edition)》 CAS 2021年第3期245-251,共7页
Screening similar historical fault-free candidate data would greatly affect the effectiveness of fault detection results based on principal component analysis(PCA).In order to find out the candidate data,this study co... Screening similar historical fault-free candidate data would greatly affect the effectiveness of fault detection results based on principal component analysis(PCA).In order to find out the candidate data,this study compares unweighted and weighted similarity factors(SFs),which measure the similarity of the principal component subspace corresponding to the first k main components of two datasets.The fault detection employs the principal component subspace corresponding to the current measured data and the historical fault-free data.From the historical fault-free database,the load parameters are employed to locate the candidate data similar to the current operating data.Fault detection method for air conditioning systems is based on principal component.The results show that the weighted principal component SF can improve the effects of the fault-free detection and the fault detection.Compared with the unweighted SF,the average fault-free detection rate of the weighted SF is 17.33%higher than that of the unweighted,and the average fault detection rate is 7.51%higher than unweighted. 展开更多
关键词 similarity factor(SF) fault detection principal component analysis(PCA) historical candidate data air conditioning system
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Similarity Reductions and Exact Solutions of a Coupled Korteweg de Vries System 被引量:1
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作者 毛杰健 杨建荣 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第4期605-608,共4页
For a special coupled Korteweg de Vries (KdV) system, its similarity solutions and reduction equations are obtained by the Clarkson and Kruskal's direct method. In addition, its new explicit soliton solutions and t... For a special coupled Korteweg de Vries (KdV) system, its similarity solutions and reduction equations are obtained by the Clarkson and Kruskal's direct method. In addition, its new explicit soliton solutions and traveling wave solutions are found by the deformation and mapping method. 展开更多
关键词 coupled KdV system similarity reduction exact solution
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