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主题还是分类学? 对事物分类倾向的发展研究 被引量:6
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作者 张佳昱 苏彦捷 《心理科学》 CSSCI CSCD 北大核心 2008年第6期1322-1325,共4页
研究旨在探讨个体分类倾向的发展趋势与影响因素。实验一采用图片、文字两种方式呈现实验材料,并使用不同指导语,要求被试选择三个事物中关系更近的两个。结果表明,成人比儿童具有更显著的按照主题分类的倾向,实验材料的呈现方式对于被... 研究旨在探讨个体分类倾向的发展趋势与影响因素。实验一采用图片、文字两种方式呈现实验材料,并使用不同指导语,要求被试选择三个事物中关系更近的两个。结果表明,成人比儿童具有更显著的按照主题分类的倾向,实验材料的呈现方式对于被试分类倾向没有显著影响。实验二进一步考察了分类倾向的发展轨迹,随着年龄增长,个体按照主题划分事物的倾向增强,由倾向于按照分类学规则向按照主题分类的转变可能发生在小学低中年级之间。 展开更多
关键词 分类 发展 主题分类 分类学分类
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从毕生发展的角度看个体分类倾向的两次转变——材料的生命性和可操作性的作用
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作者 廖宗卿 张佳昱 苏彦捷 《心理发展与教育》 CSSCI 北大核心 2015年第5期531-538,共8页
研究从毕生发展的视角考察了个体分类倾向的发展轨迹,并探讨任务材料内容可能对其产生的影响。选取幼儿园、小学、中学、大学和中老年个体各30名作为研究对象,记录他们面对不同的分类材料(有/无生命、高/低可操作性)的分类倾向。结果表... 研究从毕生发展的视角考察了个体分类倾向的发展轨迹,并探讨任务材料内容可能对其产生的影响。选取幼儿园、小学、中学、大学和中老年个体各30名作为研究对象,记录他们面对不同的分类材料(有/无生命、高/低可操作性)的分类倾向。结果表明个体的分类倾向经历了两次转变:(1)进入小学后主题分类倾向逐渐降低,并在2、3年级时最低;(2)进入中学之后,个体逐渐恢复对主题分类倾向的偏好,中学和大学的个体面对含有生命体或是可操作性高的材料会比面对非生命体或可操作性低的材料时,更倾向于使用主题分类的策略。这一结果表明,个体对不同材料内容的分类倾向的发展轨迹存在差异,研究结果有助于理解个体概念组织的形成和发展过程。 展开更多
关键词 主题分类 分类学分类 生命性 可操作性 毕生发展
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Newly recorded species of the genus Isohypsibius (Tardigrada;Hypsibiidae) from China 被引量:10
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作者 王立志 廉振民 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第4期322-324,共3页
This paper reports two newly recorded species, lsohypsibius lunulatus Iharos, 1966 and lsohypsibiusprosostomus Thulin, 1928, of the genus lsohypsibius (Tardigrada; Hypsibiidae) from China. The specimens of lsohysibi... This paper reports two newly recorded species, lsohypsibius lunulatus Iharos, 1966 and lsohypsibiusprosostomus Thulin, 1928, of the genus lsohypsibius (Tardigrada; Hypsibiidae) from China. The specimens of lsohysibius lunulatus were collected from Taibai Mt (34°18′N, 107°42′E) at 2,500 m a.s.1, and those oflsohypsibius prosostomus from Taibai Mt (34°10′N, 107°35′E) at 2,000 m above sea level. All specimens are deposited at the College of Life Sciences, Shaanxi Normal University, China. A key to the Chinese species of lsohypsibius was also given. 展开更多
关键词 TARDIGRADA TAXONOMY New record China
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Knowledge-Based Classification in Automated Soil Mapping 被引量:10
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作者 ZHOU BIN and WANG RENCHAOInstitute of Agricultural Remote Sensing and Information Technology Application, Zhejiang University, Hangzhou 310029 (China) 《Pedosphere》 SCIE CAS CSCD 2003年第3期209-218,共10页
A machine-learning approach was developed for automated building of knowledgebases for soil resources mapping by using a classification tree to generate knowledge from trainingdata. With this method, building a knowle... A machine-learning approach was developed for automated building of knowledgebases for soil resources mapping by using a classification tree to generate knowledge from trainingdata. With this method, building a knowledge base for automated soil mapping was easier than usingthe conventional knowledge acquisition approach. The knowledge base built by classification tree wasused by the knowledge classifier to perform the soil type classification of Longyou County,Zhejiang Province, China using Landsat TM bi-temporal images and CIS data. To evaluate theperformance of the resultant knowledge bases, the classification results were compared to existingsoil map based on a field survey. The accuracy assessment and analysis of the resultant soil mapssuggested that the knowledge bases built by the machine-learning method was of good quality formapping distribution model of soil classes over the study area. 展开更多
关键词 CLASSIFICATION classification tree KNOWLEDGE-BASED rule extracting soilmapping
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An Accurate and Extensible Machine Learning Classifier for Flow-Level Traffic Classification 被引量:2
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作者 Gang Lu Ronghua Guo +1 位作者 Ying Zhou Jing Du 《China Communications》 SCIE CSCD 2018年第6期125-138,共14页
Machine Learning(ML) techniques have been widely applied in recent traffic classification.However, the problems of both discriminator bias and class imbalance decrease the accuracies of ML based traffic classifier. In... Machine Learning(ML) techniques have been widely applied in recent traffic classification.However, the problems of both discriminator bias and class imbalance decrease the accuracies of ML based traffic classifier. In this paper, we propose an accurate and extensible traffic classifier. Specifically, to address the discriminator bias issue, our classifier is built by making an optimal cascade of binary sub-classifiers, where each binary sub-classifier is trained independently with the discriminators used for identifying application specific traffic. Moreover, to balance a training dataset,we apply SMOTE algorithm in generating artificial training samples for minority classes.We evaluate our classifier on two datasets collected from different network border routers.Compared with the previous multi-class traffic classifiers built in one-time training process,our classifier achieves much higher F-Measure and AUC for each application. 展开更多
关键词 traffic classification class imbalance dircriminator bias encrypted traffic machine learning
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Histotype-based prognostic classification of gastric cancer 被引量:3
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作者 Anna Maria Chiaravalli Catherine Klersy +3 位作者 Alessandro Vanoli Andrea Ferretti Carlo Capella Enrico Solcia 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第9期896-904,共9页
AIM: To test the efficiency of a recently proposed his- totype-based grading system in a consecutive series of gastric cancers.
关键词 Gastric cancer High-grade histotype Low-grade histotype Lymphoid response Epstein-Barr vi-rus Microsatellite instability
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Morphological analysis of the Chinese Cipangopaludina species(Gastropoda; Caenogastropoda: Viviparidae) 被引量:1
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作者 Hong-Fa LU Li-Na DU +2 位作者 Zhi-Qiang LI Xiao-Yong CHEN Jun-Xing YANG 《Zoological Research》 CAS CSCD 北大核心 2014年第6期510-527,共18页
Viviparidae are widely distributed around the globe, but there are considerable gaps in the taxonomic record. To date, 18 species of the viviparid genus Cipangopaludina have been recorded in China, but there is substa... Viviparidae are widely distributed around the globe, but there are considerable gaps in the taxonomic record. To date, 18 species of the viviparid genus Cipangopaludina have been recorded in China, but there is substantial disagreement on the validity of this taxonomy. In this study, we described the shell and internal traits of these species to better discuss the validity of related species. We found that C. ampulliformis is synonym of C. lecythis, and C. wingatei is synonym of C. chinensis, while C. ampullacea and C. fluminalis are subspecies of C. lecythis and C. chinensis, respectively. C. dianchiensis should be paled in the genus Margarya, while C. menglaensis and C. yunnanensis belong to genus Mekongia. Totally, this leaves 11 species and 2 subspecies recorded in China. Based on whether these specimens' spiral whorl depth was longer than aperture depth, these species or subspecies can be further divided into two groups, viz. chinensis group and cathayensis group, which can be determined from one another via the ratio of spiral depth and aperture depth, vas deferens and number of secondary branches of vas deferens. Additionally, Principal Component Analysis indicated that body whorl depth, shell width, aperture width and aperture length were main variables during species of Cipangopaludina. A key to all valid Chinese Cipangopaludina species were given. 展开更多
关键词 Cipangopaludina GASTROPODA Bellamyinae ANATOMY TAXONOMY CHINESE
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Semi-supervised Long-tail Endoscopic Image Classification
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作者 Runnan Cao Mengjie Fang +2 位作者 Hailing Li Jie Tian Di Dong 《Chinese Medical Sciences Journal》 CAS CSCD 2022年第3期171-180,I0002,共11页
Objective To explore the semi-supervised learning(SSL) algorithm for long-tail endoscopic image classification with limited annotations.Method We explored semi-supervised long-tail endoscopic image classification in H... Objective To explore the semi-supervised learning(SSL) algorithm for long-tail endoscopic image classification with limited annotations.Method We explored semi-supervised long-tail endoscopic image classification in HyperKvasir,the largest gastrointestinal public dataset with 23 diverse classes.Semi-supervised learning algorithm FixMatch was applied based on consistency regularization and pseudo-labeling.After splitting the training dataset and the test dataset at a ratio of 4:1,we sampled 20%,50%,and 100% labeled training data to test the classification with limited annotations.Results The classification performance was evaluated by micro-average and macro-average evaluation metrics,with the Mathews correlation coefficient(MCC) as the overall evaluation.SSL algorithm improved the classification performance,with MCC increasing from 0.8761 to 0.8850,from 0.8983 to 0.8994,and from 0.9075 to 0.9095 with 20%,50%,and 100% ratio of labeled training data,respectively.With a 20% ratio of labeled training data,SSL improved both the micro-average and macro-average classification performance;while for the ratio of 50% and 100%,SSL improved the micro-average performance but hurt macro-average performance.Through analyzing the confusion matrix and labeling bias in each class,we found that the pseudo-based SSL algorithm exacerbated the classifier’ s preference for the head class,resulting in improved performance in the head class and degenerated performance in the tail class.Conclusion SSL can improve the classification performance for semi-supervised long-tail endoscopic image classification,especially when the labeled data is extremely limited,which may benefit the building of assisted diagnosis systems for low-volume hospitals.However,the pseudo-labeling strategy may amplify the effect of class imbalance,which hurts the classification performance for the tail class. 展开更多
关键词 endoscopic image artificial intelligence semi-supervised learning long-tail distribution image classification
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Video learning based image classification method for object recognition
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作者 LEE Hong-ro SHIN Yong-ju 《Journal of Central South University》 SCIE EI CAS 2013年第9期2399-2406,共8页
Automatic image classification is the first step toward semantic understanding of an object in the computer vision area.The key challenge of problem for accurate object recognition is the ability to extract the robust... Automatic image classification is the first step toward semantic understanding of an object in the computer vision area.The key challenge of problem for accurate object recognition is the ability to extract the robust features from various viewpoint images and rapidly calculate similarity between features in the image database or video stream.In order to solve these problems,an effective and rapid image classification method was presented for the object recognition based on the video learning technique.The optical-flow and RANSAC algorithm were used to acquire scene images from each video sequence.After the selection of scene images,the local maximum points on comer of object around local area were found using the Harris comer detection algorithm and the several attributes from local block around each feature point were calculated by using scale invariant feature transform (SIFT) for extracting local descriptor.Finally,the extracted local descriptor was learned to the three-dimensional pyramid match kernel.Experimental results show that our method can extract features in various multi-viewpoint images from query video and calculate a similarity between a query image and images in the database. 展开更多
关键词 image classification multi-viewpoint image feature extraction video learning
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Mild Extraction Technique for Flavonoids from Leaves of Nypa fruiticans and Chemical Analysis of Its Components
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作者 Uche Eunice Ekpunobi Augustine Nnaluo Eboatu Patrice-Anthony Chudi Okoye Theresa Uzoma Onuegbu 《Journal of Chemistry and Chemical Engineering》 2012年第2期101-108,共8页
Eight flavonoid derivatives: rutin, quercetin-3-glucoside, quercetin, luteolin-7-glucoside, isorhmnetin-3-sulphate, kaempferol-3,7-diglucoside,'luteolin and kaempferol have been extracted and characterized from Nipa... Eight flavonoid derivatives: rutin, quercetin-3-glucoside, quercetin, luteolin-7-glucoside, isorhmnetin-3-sulphate, kaempferol-3,7-diglucoside,'luteolin and kaempferol have been extracted and characterized from Nipa palm. Mild extraction technique involving the use of HPLC-DAD-MS was used. The structures of the flavonoids were determined on the basis of mass spectroscopy. Separation of the crude extract by paper chromatography (PC) on forestall as solvent system gave one major yellowish brown spot which had Rf value of 3.9. The Rf value and maximum absorption from UV spectroscopy were the same as those of quercetin standard. The most prominent compound was quercetin followed by three others: kaempferol-3,7-diglucoside, luteolin-7-glucoside, and isorhmnetin-3 -sulphate. 展开更多
关键词 Nipa palm FLAVONOIDS EXTRACTS SPECTROSCOPY characterization.
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Essential Oil Composition of Four Endemic Tanacetum L. (Asteraceae) Taxa from Turkey and a Chemotaxonomic Approach
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作者 ǒmer Kilic 《Journal of Agricultural Science and Technology(A)》 2014年第3期197-202,共6页
In this study the essential oil components aerial parts of Tanacetum heterotomum (Bornm.) Grierson, T. zahlbruckneri (Nab.) Griersson, T. densum (Lab.) Schultz Bip. subsp, amani Heywood and T. cadmeum (Boiss.)... In this study the essential oil components aerial parts of Tanacetum heterotomum (Bornm.) Grierson, T. zahlbruckneri (Nab.) Griersson, T. densum (Lab.) Schultz Bip. subsp, amani Heywood and T. cadmeum (Boiss.) Heywood subsp, orientale were examined by HS-SPME/GC-MS technique. Thirty six, thirty nine, forty and forty five constituents were determined representing 88.9%, 90.1%, 90.8% and 91.5% of the oil, respectively. The main compounds of studied Tanacetum L. taxa; borneol, α-pinene, 1,8-cineole, β-pinene, camphor, germacrene D, spathulenol are determined. Studied Tanacetum taxa showed congruency with the discription in Flora of Turkey as morphological properties; on the contrary essential oil composition were detected very quiet diverse infrageneric level. Chemotypes of Tanacetum L. taxa were reported as borneol, germacrene D, spathulenol, α-pinene, 1,8-cineole, β-pinene and camphor. The results obtained from this study were discussed in terms of chemotaxonomy and natural products. 展开更多
关键词 Tanacetum L. essential oil CHEMOTAXONOMY natural products.
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Variable Sets principle and method for flood classification 被引量:23
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作者 CHEN ShouYu XUE ZhiChun LI Min 《Science China(Technological Sciences)》 SCIE EI CAS 2013年第9期2343-2348,共6页
Flood classification is an effective way to improve flood forecasting accuracy. According to the opposite unity mathematical theorem in Variable Sets theory, this paper proposes a Variable Sets principle and method fo... Flood classification is an effective way to improve flood forecasting accuracy. According to the opposite unity mathematical theorem in Variable Sets theory, this paper proposes a Variable Sets principle and method for flood classification, which is based on the mathematical theorem of dialectics basic laws. This newly proposed method explores a novel way to analyze and solve engineering problems by utilizing a dialectical thinking. In this paper, the Tuwei River basin, located in the Yellow River tributary, is taken as an example for flood classification. The results obtained in this study reveal the problems in a previous method—Set Pair Analysis classification method. The variable sets method is proven to be theoretically rigorous, computationally simple. The classification results are objective, accurate and consistent with the actual situations. This study demonstrates the significant importance of using a scientifically sound method in solving engineering problems. 展开更多
关键词 flood classification Variable Sets opposite unity theorem gradually qualitative change Set Pair Analysis
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Hybridization and the species problem in conservation
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作者 Benjamin M. FITZPATRICK Maureen E. RYAN +2 位作者 Jarrett R. JOHNSON Joel CORUSH Evin T. CARTER 《Current Zoology》 SCIE CAS CSCD 2015年第1期206-216,共11页
Most biologists recognize the "species phenomenon" as a real pattern in nature: Biodiversity is characterized by dis- continuities between recognizable groups classified as species. Many conservation laws focus on ... Most biologists recognize the "species phenomenon" as a real pattern in nature: Biodiversity is characterized by dis- continuities between recognizable groups classified as species. Many conservation laws focus on preventing species extinction. However, species are not fixed. Discontinuities evolve gradually and sometimes disappear. Exactly how to define particular spe- cies is not always obvious. Hybridization between taxonomic species reminds us that species classification is not a perfect repre- sentation of nature. Classification is a model that is very useful, but not adequate in all cases. Conservationists often confront questions about how to apply species-based laws when hybridization confounds classification. Development of sophisticated techniques and nuanced interpretation of data in the basic study of species and speciation has exposed the need for deeper educa- tion in genetics and evolution for applied conservationists and decision makers. Here we offer a brief perspective on hybridiza- tion and the species problem in conservation. Our intended audience is conservation practitioners and decision-makers more than geneticists and evolutionary biologists. We wish to emphasize that the goals and premises of legislative classification are not identical to those of scientific classification. Sometimes legal classification is required when the best available science indicates that discrete classification is not an adequate model for the case. Establishing legal status and level of protection for hybrids and hybrid populations means choosing from a range of scientifically valid alternatives. Although we should not abandon species-based approaches to conservation, we must recognize their limitations and work to clarify the roles of science and values in ethical and legal decisions [Current Zoology 61 (1): 206-216, 2015]. 展开更多
关键词 HYBRIDIZATION Hybrid zone CONSERVATION GENETICS POLICY CLASSIFICATION DELIMITATION
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Study of Substrate and Physico-Chemical Base Classification of the Rivers of Nepal
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作者 JHA Bibhuti Ranjan WAIDBACHER Herwig +1 位作者 SHARMA Subodh STRAIF Michael 《Geo-Spatial Information Science》 2010年第1期70-76,共7页
The rivers in Nepal are classified in terms of geographical regions but a more scientific classification such as on the ba-sis of morphology is clearly lacking. This study was done in 9 rivers namely Jhikhukhola of th... The rivers in Nepal are classified in terms of geographical regions but a more scientific classification such as on the ba-sis of morphology is clearly lacking. This study was done in 9 rivers namely Jhikhukhola of the Koshi system, Aandhikhola, Arungkhola, East Rapti, Karrakhola, Seti and main channel Narayani of the Gandaki system, and two independent systems within Nepal, Bagmati and Tinau. Among the morphologies, river bed or the substratum was taken as the main variable for the analysis which was categorized into 7 types as rocks, boulders, cobbles, pebbles, gravels, sand and silt. There were 23 sampling sites each with 2 stretches of around 100m in those rivers. The data were taken as a percentage, and to avoid biases it was observed visually by the same person for a complete year in every season. With 23 sites each with 2 stretches and 4 replicates corresponding to 4 seasons, there are altogether 184 observations, each termed as a case, that constitute this work. Canonical Discrimination Analysis (CDA) which is most suitable when the data pool is huge was applied to see if the rivers studied distinguish themselves in terms of its morphology. The result was remarkably successful and was close to the established regional classification of the rivers. This kind of river classification has great application in the utilization, conservation and restoration of the most important natural re-source of the country. 展开更多
关键词 Nepal rivers morphology physico-chemical parameter river classification
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