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Categorized Analysis of Forest Ecological Values in the China’s Conversion Cropland to Forest Program
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作者 RONG Yanju YUAN Wenge +3 位作者 GU Jiancai LU Guiqiao ZHENG Jianwei WEN Zhehua 《Journal of Landscape Research》 2020年第6期21-29,34,共10页
The China’s Conversion Cropland to Forest Program(CCFP)is one of the largest national ecological construction programs,which has effectively improved ecological environment and produced large ecological benefi t.To p... The China’s Conversion Cropland to Forest Program(CCFP)is one of the largest national ecological construction programs,which has effectively improved ecological environment and produced large ecological benefi t.To provide references for further improving ecological benefi t of CCFP,we analyzed the features,differences and relationships of the categorized forest ecological“benefi t value”(B-V)s in 3 kinds of forest restoration ways in different regions in CCFP,using the data of Chinese Forest Ecosystem Research Network(CFERN)from 1999 to 2013 and the methods of the national standards of(LY/T1606-2003),(LY/T1721-2008)and(LY/T1952-2011).The result showed that annual B-Vs of unit area varied in the range of 3.5-10.0 e4 RMBs/hm2·a.Water conservation B-Vs and species conservation B-Vs are the 2 largest constituents,nutrient accumulation B-V was the least in total B-Vs.The B-Vs performed inconsistently among the forest restoration ways and different regions.The rank of average annual total B-Vs of unit area from high to low was“hillside forest conservation”,“returning cropland to forest”,“afforestation on suitable barren hills and wasteland”.Species conservation B-Vs and water conservation B-Vs in southern regions were higher than that of northern and northwestern regions in China.The hot and rainy regions could produce higher species conservation B-Vs.The regression analysis indicated that water conservation B-Vs had signifi cantly positive correlation with the relevant total B-Vs and positive correlation with the relevant atmosphere purification B-Vs whether in regional or in unit area scale.Unit area species conservation B-V was negatively correlated with the relevant nutrient accumulation B-Vs except the way of“afforestation on suitable barren hills and wasteland”.Regional total species conservation B-Vs had signifi cantly negative correlation with its relevant nutrient accumulation B-Vs except“hillside forest conservation”way.We suggest that suitable forest restoration ways must be selective according to the regional specifi c,B-V features and local ecological goals. 展开更多
关键词 categorized analysis Forest ecological benefi t value(B-V) Restoration way CFERN CCFP
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Should eSports Be Categorized as Sports Events?
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《ChinAfrica》 2018年第11期12-13,共2页
Don't be surprisod if someone tolls you that you can win a world championship by playing online games.Competitive online gaming,or eSports,has debuted as a demonstration sport at the 18th Asian Games held in Jakarta.
关键词 Should eSports Be categorized as Sports Events
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Study on the Complex Prescription Compatibility Law of the Cold and Hot Nature of Mahuang Decoction(麻黄汤) and Its Categorized Formulae Based on the Cold-Hot Pad Differentiating Assay 被引量:1
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作者 贾雷 赵艳玲 +5 位作者 王伽伯 邹文俊 李瑞生 杨宏博 程丹红 肖小河 《Chinese Journal of Integrative Medicine》 SCIE CAS 2011年第4期290-295,共6页
Objective:To explore the complex prescription compatibility law of the cold and hot nature of Mahuang Decoction(麻黄汤,MHD) and Maxing Shigan Decoction(麻杏石甘汤,MXSGD),both categorized formulas but with differe... Objective:To explore the complex prescription compatibility law of the cold and hot nature of Mahuang Decoction(麻黄汤,MHD) and Maxing Shigan Decoction(麻杏石甘汤,MXSGD),both categorized formulas but with different hot/cold natures.Methods:Oxygen consumption of mice was determined among three groups:MHD,MXSGD and the control;a cold-hot pad differentiating assay was used to observe the variability of temperature tropism among the groups of mice which was treated with MHD,MXSGD,and their compositions. Meanwhile,the total anti-oxidant capability(T-AOC) activity were detected.Results:After administration of MHD, the mice showed increased oxygen consumption(P0.01).Compared with MHD group,the remaining rate of MXSGD mice on the hot pad was found to be significantly increased with the cold-hot pad differentiating assay (P0.05).There was no significant difference(P0.05) among the remaining rates of MXSGD,MXSGD with high dose Gypsum Fibrosum(MXHGF) group,and MXSGD with low dose Gypsum Fibrosum(MXLGF) group mice.Compared with the MHD group,T-AOC activity of the mice in the Consensus Compositons group was significantly decreased(P=0.0494).Compared with the MXSGD group,T-AOC activity of Gypsum Fibrosum (GF) group was increased significantly(P=0.0013).Conclusions:The differences in cold and hot nature could be represented objectively between MHD with a hot nature and MXSGD with a cold nature.The reason may be the Gypsum Fibrosum which decreased the efficacy of the consensus compositions.However,increasing or decreasing the dose of Gypsum Fibrosum will not change the cold and hot nature of MXSGD. 展开更多
关键词 Mahuang Decoction and its categorized formulae cold and hot nature of Chinese drugs complex prescription compatibility law of Chinese medicine cold-hot pad differentiating assay
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某三级甲等专科医院推进互联网分级诊疗的思考 被引量:13
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作者 谢诗蓉 叶卿云 +4 位作者 王晨颖 陈琼洲 史晓诞 丁晓璟 叶正强 《中国卫生资源》 CSCD 北大核心 2023年第4期393-396,403,共5页
复旦大学附属眼耳鼻喉科医院在发展互联网医院的基础上,积极探索建立互联网分级诊疗。与全国6省(市)11个地区的16家医院达成互联网分级诊疗战略合作,利用专科医院优势,通过远程会诊、远程教学、科普直播等多项举措共同推进互联网分级诊... 复旦大学附属眼耳鼻喉科医院在发展互联网医院的基础上,积极探索建立互联网分级诊疗。与全国6省(市)11个地区的16家医院达成互联网分级诊疗战略合作,利用专科医院优势,通过远程会诊、远程教学、科普直播等多项举措共同推进互联网分级诊疗。在推进互联网分级诊疗的过程中遇到了远程需求较少、药品配送困难、精准转诊率低、费用结算不明、利益分配不均等难点。应积极尝试从加强医疗联合体合作关系、增加医疗联合体药品目录、加强基层培训、完善医疗联合体利益分配和构建当地眼健康档案等方面进一步完善互联网分级诊疗。 展开更多
关键词 专科医院specialist hospital 互联网医院internet hospital 分级诊疗categorized treatment
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Neural Basis of Categorical Representations of Animal Body Silhouettes
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作者 Yue Pu Shihui Han 《Neuroscience Bulletin》 2025年第2期211-223,共13页
Neural activities differentiating bodies versus non-body stimuli have been identified in the occipitotemporal cortex of both humans and nonhuman primates.However,the neural mechanisms of coding the similarity of diffe... Neural activities differentiating bodies versus non-body stimuli have been identified in the occipitotemporal cortex of both humans and nonhuman primates.However,the neural mechanisms of coding the similarity of different individuals’bodies of the same species to support their categorical representations remain unclear.Using electroencephalography(EEG)and magnetoencephalography(MEG),we investigated the temporal and spatial characteristics of neural processes shared by different individual body silhouettes of the same species by quantifying the repetition suppression of neural responses to human and animal(chimpanzee,dog,and bird)body silhouettes showing different postures.Our EEG results revealed significant repetition suppression of the amplitudes of early frontal/central activity at 180–220 ms(P2)and late occipitoparietal activity at 220–320 ms(P270)in response to animal(but not human)body silhouettes of the same species.Our MEG results further localized the repetition suppression effect related to animal body silhouettes in the left supramarginal gyrus and left frontal cortex at 200–440 ms after stimulus onset.Our findings suggest two neural processes that are involved in spontaneous categorical representations of animal body silhouettes as a cognitive basis of human-animal interactions. 展开更多
关键词 Body silhouette CATEGORIZATION Repression suppression EEG MEG
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Integrating categorical and standard triple collocation to improve precipitation fusion over the five largest freshwater lakes in China
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作者 LI Lingjie TANG Guoqiang +4 位作者 WANG Yintang GAO Rui LIU Yong ZHAO Wenpeng CHEN Cheng 《Journal of Geographical Sciences》 2025年第11期2378-2412,共35页
The sparsity of ground gauges poses a significant challenge for evaluating and merging satellite-based and reanalysis-based precipitation datasets in lake regions.While the standard triple collocation(TC)method offers... The sparsity of ground gauges poses a significant challenge for evaluating and merging satellite-based and reanalysis-based precipitation datasets in lake regions.While the standard triple collocation(TC)method offers a solution without access to ground-based observations,it fails to address rain/no-rain classification and its suitability for assessing and merging lake precipitation has not been explored.This study combines categorical triple collocation(CTC)with standard TC to create an integrated framework(CTC-TC)tailored to evaluate and merge global gridded precipitation products(GPPs).We assess the efficacy of CTC-TC using six GPPs(ERA5-Land,SM2 RAIN-ASCAT,IMERG-Early,IMERG-Late,GSMaPMVK,and PERSIANN-CCS)across the five largest freshwater lakes in China.CTC-TC effectively captures the spatial patterns of metrics for all GPPs,and precisely estimates the correlation coefficient and root mean square error for satellite-based datasets apart from SM2 RAIN-ASCAT,but overestimates the classification accuracy indicator V for all GPPs.Regarding multi-source fusion,CTC-TC leverages the strengths of individual products of triplets,resulting in significant improvements in the critical success index(CSI)by over 11.9%and the modified Kling-Gupta efficiency(KGE')by more than 13.3%.Compared to baseline models,including standard TC,simple model averaging,one outlier removal,and Bayesian model averaging,CTC-TC achieves gains in CSI and KGE'of no less than 24.7%and 3.6%,respectively.In conclusion,the CTC-TC framework offers a thorough evaluation and efficient fusion of GPPs,addressing both categorical and continuous accuracy in data-scarce regions such as lakes. 展开更多
关键词 categorical triple collocation triple collocation lake gridded precipitation datasets accuracy assessment multi-source fusion
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Surprisal-based algorithm for detecting anomalies in categorical data
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作者 Ossama Cherkaoui Houda Anoun Abderrahim Maizate 《Data Science and Management》 2025年第2期185-195,共11页
Anomaly detection is an important research area in a diverse range of real-world applications.Although many algorithms have been proposed to address anomaly detection for numerical datasets,categorical and mixed datas... Anomaly detection is an important research area in a diverse range of real-world applications.Although many algorithms have been proposed to address anomaly detection for numerical datasets,categorical and mixed datasets remain a significant challenge,primarily because a natural distance metric is lacking.Consequently,the methods proposed in the literature implement entirely different assumptions regarding the definition of cate-gorical anomalies.This paper presents a novel categorical anomaly detection approach,offering two key con-tributions to existing methods.First,a novel surprisal-based anomaly score is introduced,which provides a more accurate assessment of anomalies by considering the full distribution of categorical values.Second,the proposed method considers complex correlations in the data beyond the pairwise interactions of features.This study proposed and tested the novel categorical surprisal anomaly detection algorithm(CSAD)by comparing and evaluating it against six competitors.The experimental results indicate that CSAD produced the best overall performance,achieving the highest average ROC-AUC and PR-AUC values of 0.8 and 0.443,respectively.Furthermore,CSAD's execution time is satisfactory even when processing large,high-dimensional datasets. 展开更多
关键词 Unsupervised learning Anomaly detection Categorical data Surprisal anomaly score
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CARE:Comprehensive Artificial Intelligence Techniques for Reliable Autism Evaluation in Pediatric Care
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作者 Jihoon Moon Jiyoung Woo 《Computers, Materials & Continua》 2025年第10期1383-1425,共43页
Improving early diagnosis of autism spectrum disorder(ASD)in children increasingly relies on predictive models that are reliable and accessible to non-experts.This study aims to develop such models using Python-based ... Improving early diagnosis of autism spectrum disorder(ASD)in children increasingly relies on predictive models that are reliable and accessible to non-experts.This study aims to develop such models using Python-based tools to improve ASD diagnosis in clinical settings.We performed exploratory data analysis to ensure data quality and identify key patterns in pediatric ASD data.We selected the categorical boosting(CatBoost)algorithm to effectively handle the large number of categorical variables.We used the PyCaret automated machine learning(AutoML)tool to make the models user-friendly for clinicians without extensive machine learning expertise.In addition,we applied Shapley additive explanations(SHAP),an explainable artificial intelligence(XAI)technique,to improve the interpretability of the models.Models developed using CatBoost and other AI algorithms showed high accuracy in diagnosing ASD in children.SHAP provided clear insights into the influence of each variable on diagnostic outcomes,making model decisions transparent and understandable to healthcare professionals.By integrating robust machine learning methods with user-friendly tools such as PyCaret and leveraging XAI techniques such as SHAP,this study contributes to the development of reliable,interpretable,and accessible diagnostic tools for ASD.These advances hold great promise for supporting informed decision-making in clinical settings,ultimately improving early identification and intervention strategies for ASD in the pediatric population.However,the study is limited by the dataset’s demographic imbalance and the lack of external clinical validation,which should be addressed in future research. 展开更多
关键词 Autism spectrum disorder pediatric care exploratory data analysis categorical boosting automated machine learning explainable artificial intelligence Shapley additive explanations
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Text categorization based on fuzzy classification rules tree 被引量:2
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作者 郭玉琴 袁方 刘海博 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期339-342,共4页
To deal with the problem that arises when the conventional fuzzy class-association method applies repetitive scans of the classifier to classify new texts,which has low efficiency, a new approach based on the FCR-tree... To deal with the problem that arises when the conventional fuzzy class-association method applies repetitive scans of the classifier to classify new texts,which has low efficiency, a new approach based on the FCR-tree(fuzzy classification rules tree)for text categorization is proposed.The compactness of the FCR-tree saves significant space in storing a large set of rules when there are many repeated words in the rules.In comparison with classification rules,the fuzzy classification rules contain not only words,but also the fuzzy sets corresponding to the frequencies of words appearing in texts.Therefore,the construction of an FCR-tree and its structure are different from a CR-tree.To debase the difficulty of FCR-tree construction and rules retrieval,more k-FCR-trees are built.When classifying a new text,it is not necessary to search the paths of the sub-trees led by those words not appearing in this text,thus reducing the number of traveling rules.Experimental results show that the proposed approach obviously outperforms the conventional method in efficiency. 展开更多
关键词 text categorization fuzzy classification association rule classification rules tree fuzzy classification rules tree
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认知过程的翻译理论研究 被引量:6
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作者 李平 《上海翻译》 CSSCI 北大核心 1999年第4期14-15,共2页
The recent developments of cognitive theories may provide a better interpretation for studies of translation rather than a description.The paper tries to put categorization and metaphor into the process of translating... The recent developments of cognitive theories may provide a better interpretation for studies of translation rather than a description.The paper tries to put categorization and metaphor into the process of translating and translators’ psychology so as to produce a more powerful interpretation. [ 展开更多
关键词 COGNITION INTERPRETATION CATEGORIZATION METAPHOR
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Evaluating changes in ecological land and effect of protecting important ecological spaces in China 被引量:3
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作者 GAO Jixi LIU Xiaoman +4 位作者 WANG Chao WANG Yong FU Zhuo HOU Peng LYU Na 《Journal of Geographical Sciences》 SCIE CSCD 2021年第9期1245-1260,共16页
It is important to quantitatively analyze the effects of protection of important ecological spaces in China to ensure national ecological security.By considering changes in the ecological land,this study examines the ... It is important to quantitatively analyze the effects of protection of important ecological spaces in China to ensure national ecological security.By considering changes in the ecological land,this study examines the effects of protecting three types of important natural ecological spaces in China from 1980 to 2018.Moreover,considering important ecological spaces and their surroundings yields differences in the effects of protection between internal and external spaces,where this can provide a scientific basis for the categorization and zoning of China’s land.The results show the following:(1)In 2018,the ratio of ecological land to important natural ecological spaces accounted for 92.64%.This land had a good ecological background that reflects the developmental orientation of important ecological spaces.(2)From 1980 to 2018,the area of ecological land in important ecological spaces shrank but the rate of reduction was lower than the national average,which shows the positive effect of regulating construction in natural ecological spaces.The restorative effects of ecological projects to convert farmland into forests and grasslands have been prominent.The expanded ecological land is mainly distributed in areas where such projects have been implemented,and the reduced area is concentrated in grain-producing areas of the Northeast China Plain and agricultural oases of Xinjiang.In the future,the government should focus on strengthening the management and control of these areas.(3)The area ratio of ecological land was the highest in national nature reserves.The rate of reduction in its area was the lowest and the trend of reduction was the smallest in national nature reserves,which reflects differences in the status of ecological protection among different spaces.(4)The ratio of ecological land to important ecological spaces was higher than that in the surrounding external space,and the rate of reduction in it was lower.Thus,the effects of internal and external protection had clear differences in terms of gradient. 展开更多
关键词 ecological spaces ecological land spatial and temporal dynamic changes protection effect categorized and zoned governance
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A Novel Active Learning Method Using SVM for Text Classification 被引量:26
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作者 Mohamed Goudjil Mouloud Koudil +1 位作者 Mouldi Bedda Noureddine Ghoggali 《International Journal of Automation and computing》 EI CSCD 2018年第3期290-298,共9页
Support vector machines(SVMs) are a popular class of supervised learning algorithms, and are particularly applicable to large and high-dimensional classification problems. Like most machine learning methods for data... Support vector machines(SVMs) are a popular class of supervised learning algorithms, and are particularly applicable to large and high-dimensional classification problems. Like most machine learning methods for data classification and information retrieval, they require manually labeled data samples in the training stage. However, manual labeling is a time consuming and errorprone task. One possible solution to this issue is to exploit the large number of unlabeled samples that are easily accessible via the internet. This paper presents a novel active learning method for text categorization. The main objective of active learning is to reduce the labeling effort, without compromising the accuracy of classification, by intelligently selecting which samples should be labeled.The proposed method selects a batch of informative samples using the posterior probabilities provided by a set of multi-class SVM classifiers, and these samples are then manually labeled by an expert. Experimental results indicate that the proposed active learning method significantly reduces the labeling effort, while simultaneously enhancing the classification accuracy. 展开更多
关键词 Text categorization active learning support vector machine (SVM) pool-based active learning pairwise coupling.
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Pseudogenes:Pseudo or Real Functional Elements? 被引量:8
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作者 Wen Li Wei Yang Xiu-Jie Wang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2013年第4期171-177,共7页
Pseudogenes are genomic remnants of ancient protein-coding genes which have lost their coding potentials through evolution.Although broadly existed,pseudogenes used to be considered as junk or relics of genomes which ... Pseudogenes are genomic remnants of ancient protein-coding genes which have lost their coding potentials through evolution.Although broadly existed,pseudogenes used to be considered as junk or relics of genomes which have not drawn enough attentions of biologists until recent years.With the broad applications of high-throughput experimental techniques,growing lines of evidence have strongly suggested that some pseudogenes possess special functions,including regulating parental gene expression and participating in the regulation of many biological processes.In this review,we summarize some basic features of pseudogenes and their functions in regulating development and diseases.All of these observations indicate that pseudogenes are not purely dead fossils of genomes,but warrant further exploration in their distribution,expression regulation and functions.A new nomenclature is desirable for the currently called 'pseudogenes' to better describe their functions. 展开更多
关键词 PSEUDOGENE CATEGORIZATION ORIGINATION Function
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A New Approach of Feature Selection for Text Categorization 被引量:6
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作者 CUI Zifeng XU Baowen +1 位作者 ZHANG Weifeng XU Junling 《Wuhan University Journal of Natural Sciences》 CAS 2006年第5期1335-1339,共5页
This paper proposes a new approach of feature selection based on the independent measure between features for text categorization. A fundamental hypothesis that occurrence of the terms in documents is independent of e... This paper proposes a new approach of feature selection based on the independent measure between features for text categorization. A fundamental hypothesis that occurrence of the terms in documents is independent of each other, widely used in the probabilistic models for text categorization (TC), is discussed. However, the basic hypothesis is incom plete for independence of feature set. From the view of feature selection, a new independent measure between features is designed, by which a feature selection algorithm is given to ob rain a feature subset. The selected subset is high in relevance with category and strong in independence between features, satisfies the basic hypothesis at maximum degree. Compared with other traditional feature selection method in TC (which is only taken into the relevance account), the performance of feature subset selected by our method is prior to others with experiments on the benchmark dataset of 20 Newsgroups. 展开更多
关键词 feature selection independency CHI square test text categorization
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Comparison of Text Categorization Algorithms 被引量:4
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作者 SHIYong-feng ZHAOYan-ping 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第5期798-804,共7页
This paper summarizes several automatic text categorization algorithms in common use recently, analyzes and compares their advantages and disadvantages. It provides clues for making use of appropriate automatic classi... This paper summarizes several automatic text categorization algorithms in common use recently, analyzes and compares their advantages and disadvantages. It provides clues for making use of appropriate automatic classifying algorithms in different fields. Finally some evaluations and summaries of these algorithms are discussed, and directions to further research have been pointed out. Key words text categorization - naive bayes - KNN - SVM - neural network CLC number TP 391 Foundation item: Supported by the National Natural Science Foundation of China (70031010) and the Research Foundation of Beijing Institute of TechnologyBiography: SHI Yong-feng (1980-), male, Master candidate, research direction: web information mining. 展开更多
关键词 text categorization naive bayes KNN SVM neural network
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Protocol Format Extraction Based on an Improved CFSM Algorithm 被引量:4
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作者 Peihong Lin Zheng Hong +2 位作者 Lifa Wu Yihao Li Zhenji Zhou 《China Communications》 SCIE CSCD 2020年第11期156-180,共25页
As the information technology rapidly develops,many network applications appear and their communication protocols are unknown.Although many protocol keyword recognition based protocol reverse engineering methods have ... As the information technology rapidly develops,many network applications appear and their communication protocols are unknown.Although many protocol keyword recognition based protocol reverse engineering methods have been proposed,most of the keyword recognition algorithms are time consuming.This paper firstly uses the traffic clustering method F-DBSCAN to cluster the unknown protocol traffic.Then an improved CFSM(Closed Frequent Sequence Mining)algorithm is used to mine closed frequent sequences from the messages and identify protocol keywords.Finally,CFGM(Closed Frequent Group Mining)algorithm is proposed to explore the parallel,sequential and hierarchical relations between the protocol keywords and obtain accurate protocol message formats.Experimental results show that the proposed protocol formats extraction method is better than Apriori algorithm and Sequence alignment algorithm in terms of time complexity and it can achieve high keyword recognition accuracy.Additionally,based on the relations between the keywords,the method can obtain accurate protocol formats.Compared with the protocol formats obtained from the existing methods,our protocol format can better grasp the overall structure of target protocols and the results perform better in the application of protocol reverse engineering such as fuzzing test. 展开更多
关键词 flow clustering CFSM algorithm closed frequent sequences keyword recognition CFGM algorithm keyword relations format categorization
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Cystic duct cancer: Should it be deemed as a type of gallbladder cancer? 被引量:3
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作者 Tu-Nan Yu Ying-Ying Mao +1 位作者 Fang-Qiang Wei Hui Liu 《World Journal of Gastroenterology》 SCIE CAS 2019年第44期6541-6550,共10页
BACKGROUND According to the latest American Joint Committee on Cancer and Union for International Cancer Control manuals,cystic duct cancer(CC)is categorized as a type of gallbladder cancer(GC),which has the worst pro... BACKGROUND According to the latest American Joint Committee on Cancer and Union for International Cancer Control manuals,cystic duct cancer(CC)is categorized as a type of gallbladder cancer(GC),which has the worst prognosis among all types of biliary cancers.We hypothesized that this categorization could be verified by using taxonomic methods.AIM To investigate the categorization of CC based on population-level data.METHODS Cases of biliary cancers were identified from the Surveillance,Epidemiology,and End Results 18 registries database.Together with routinely used statistical methods,three taxonomic methods,including Fisher’s discriminant,binary logistics and artificial neuron network(ANN)models,were used to clarify the categorizing problem of CC.RESULTS The T staging system of perihilar cholangiocarcinoma[a type of extrahepatic cholangiocarcinoma(EC)]better discriminated CC prognosis than that of GC.After adjusting other covariates,the hazard ratio of CC tended to be closer to that of EC,although not reaching statistical significance.To differentiate EC from GC,three taxonomic models were built and all showed good accuracies.The ANN model had an area under the receiver operating characteristic curve of 0.902.Using the three models,the majority(75.0%-77.8%)of CC cases were categorized as EC.CONCLUSION Our study suggested that CC should be categorized as a type of EC,not GC.Aggressive surgical attitude might be considered in CC cases,to see whether long-term prognosis could be immensely improved like the situation in EC. 展开更多
关键词 CYSTIC duct CANCER GALLBLADDER CANCER EXTRAHEPATIC CHOLANGIOCARCINOMA Surgical management Taxonomy CATEGORIZATION
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A High-Performance Extraction Method for Public Opinion on Internet 被引量:3
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作者 LI Yanling DAI Guanzhong +1 位作者 ZHU Yehang QIN Sen 《Wuhan University Journal of Natural Sciences》 CAS 2007年第5期902-906,共5页
Aiming at the importance of the analysis for public opinion on Internet, the authors propose a high-performance extraction method for public opinion. In this method, the space model for classification is adopted to de... Aiming at the importance of the analysis for public opinion on Internet, the authors propose a high-performance extraction method for public opinion. In this method, the space model for classification is adopted to describe the relationship between words and categories. The combined feature selection method is used to remove noisy words from the original feature space effectively. Then the category weight of words is calculated by the improved formula combining the frequency of words and distribution of words. Finally, the class weights of the not-categorized documents based on the category weight of words are obtained for realizing opinion extraction. Experiment results show that the method has comparatively high classification and good stability. 展开更多
关键词 opinion extraction text categorization class spacemodel feature selection
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Identification and Categorization of Climate Change Risks 被引量:2
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作者 ZHANG Yuchong WU Shaohong +2 位作者 DAI Erfu LIU Dengwei YIN Yunhe 《Chinese Geographical Science》 SCIE CSCD 2008年第3期268-275,共8页
The scientific evidence that climate is changing due to greenhouse gas emission is now incontestable, which may put many social, biological, and geophysical systems in the world at risk. In this paper, we first identi... The scientific evidence that climate is changing due to greenhouse gas emission is now incontestable, which may put many social, biological, and geophysical systems in the world at risk. In this paper, we first identified main risks induced from or aggravated by climate change. Then we categorized them applying a new risk categorization system brought forward by Renn in a framework of International Risk Governance Council. We proposed that "uncertainty" could be treated as the classification criteria. Based on this, we established a quantitative method with fuzzy set theory, in which "confidence" and "likelihood", the main quantitative terms for expressing uncertainties in IPCC, were used as the feature parameters to construct the fuzzy membership functions of four risk types. According to the maximum principle, most climate change risks identified were classified into the appropriate risk types. In the mean time, given that not all the quantitative terms are available, a qualitative approach was also adopted as a complementary classification method. Finally, we get the preliminary results of climate change risk categorization, which might iay the foundation for the future integrated risk management of climate change. 展开更多
关键词 climate change risk identification risk categorization UNCERTAINTY degree of membership
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A COMPARISON OF ALTERNATIVE CRITERIA FOR DEFINING FUZZY BOUNDARIES ON FUZZY CATEGORICAL MAPS 被引量:1
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作者 ZHANG Jingxiong Roger P.Kirby 《Geo-Spatial Information Science》 2000年第2期26-34,共9页
This paper provides a brief introduction to the methods for generating fuzzy categorical maps from remotely sensed images (in graphical and digital forms).This is followed by a description of the slicing process for d... This paper provides a brief introduction to the methods for generating fuzzy categorical maps from remotely sensed images (in graphical and digital forms).This is followed by a description of the slicing process for deriving fuzzy boundaries from fuzzy categorical maps,which can be based on the maximum fuzzy membership values,confusion index,or measure of entropy.Results from an empirical test preformed in an Edinburgh suburb show that fuzzy boundaries of land cover can be derived from aerial photographs and satellite images by using the three criteria with small differences,and that slicing based on the maximum fuzzy membership values is the easiest and most straightforward solution.This,in turn,implies the suitability of maintaining both a crisp classification and its underlying certainty map for deriving fuzzy boundaries at different thresholds,which is a flexible and compact management of categorical map data and their uncertainty. 展开更多
关键词 CATEGORICAL mapping objects FIELDS FUZZY CATEGORICAL MAPS FUZZY MEMBERSHIP VALUES (FMVs) FUZZY boundaries
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