期刊文献+
共找到9篇文章
< 1 >
每页显示 20 50 100
一种基于支持向量机的人类动作分类方法 被引量:2
1
作者 李万福 《中国新通信》 2019年第9期75-76,共2页
本文研究了基于微多普勒现象的信号特征提取和基于支持向量机的人类不同动作的分类方法。在经过处理的微多普勒信号频谱中提取了能够表述人类目标动作的6个特征。将提取到的6个特征作为动作模式的特征向量,利用经过监督训练的支持向量... 本文研究了基于微多普勒现象的信号特征提取和基于支持向量机的人类不同动作的分类方法。在经过处理的微多普勒信号频谱中提取了能够表述人类目标动作的6个特征。将提取到的6个特征作为动作模式的特征向量,利用经过监督训练的支持向量机来分类不同动作。文中的多类别分类问题则利用了决策树结构分解为多个两类别分类问题。并通过四重交叉验证方法寻找到了支持向量机的最优化参数。最终的分类准确率超过了90%。 展开更多
关键词 人类动作分类 微多普勒 支持向量机
下载PDF
类别学习和分类运用的神经机制 被引量:6
2
作者 佐斌 张晓斌 《心理科学进展》 CSSCI CSCD 北大核心 2011年第6期843-852,共10页
从类别学习和分类运用(包括非人类对象分类和社会分类)两个方面阐述了分类的神经机制。类别学习主要与新皮层、内侧颞叶、基底神经节、中脑多巴胺能系统有关,不同类别的学习会激活这些神经系统间不同的连接。对非人类对象分类时,不同类... 从类别学习和分类运用(包括非人类对象分类和社会分类)两个方面阐述了分类的神经机制。类别学习主要与新皮层、内侧颞叶、基底神经节、中脑多巴胺能系统有关,不同类别的学习会激活这些神经系统间不同的连接。对非人类对象分类时,不同类型、级别、熟悉度及相似度类别分类的神经机制不同,分类对象的清晰度、类别不确定性会影响分类的神经机制,在分类进程的不同时段会出现对应的ERP指标。社会分类时个体先注意到外群体再加工内群体,且对内群体的加工更深,P200和N200是对内、外群体区分的特异性波,内外群体分类时,内群体激活梭状回和扣带回后部,外群体激活杏仁核。文章最后比较了人类和灵长类动物分类神经机制的异同,并指出社会分类和非人类对象分类神经机制的整合以及人类和灵长类动物分类神经机制的比较是今后研究需要关注的问题。 展开更多
关键词 类别学习 人类对象分类 社会分类 灵长类动物分类 神经机制
下载PDF
尼采论智识阶级
3
作者 张旭东 《批评家茶座》 2003年第1期54-59,共6页
关键词 尼采 智识阶级 现代人 人类分类 知识分子
下载PDF
APPLYING PPE MODEL BASED ON RAGA TO CLASSIFYAND EVALUATE SOIL GRADE 被引量:19
4
作者 FU Qiang1,2, LU Tie guang2, FU Hong2(1. College of Hydraulic Power, Sichuan University, Chengdu 610065, P.R.China 2. Northeast Agricultural University, Harbin 150030, P. R. China) 《Chinese Geographical Science》 SCIE CSCD 2002年第2期136-141,共6页
The research of soil classification and soil grade evaluation is often based on fuzzy theory. So, the traditional method has an inevitable problem about weight matrix which given by some experts, and the final result ... The research of soil classification and soil grade evaluation is often based on fuzzy theory. So, the traditional method has an inevitable problem about weight matrix which given by some experts, and the final result can be influenced by artificial factors. The essentials of fuzzy synthetically judge is to handle the data of high dimension. That is to reducing the dimension number. The weight matrix in fuzzy theory is corresponding to low dimension projection value of each index. But we can′t define whether the weight matrix given by experts is the best projection value or not. So, the authors apply a new technique of falling dimension named projection pursuit to soil study, through using the improved real coding based accelerating genetic algorithm to optimize the projection direction. Thus, it can transfer multi dimension data into one dimension data, through searching for the optimum projection direction to realize the soil classification and its grade evaluation. The method can avoid the artificial disturbance, and acquire preferably effect. Thus, the paper provides a new method to the research of soil classification and grade evaluation. 展开更多
关键词 RAGA PPE soil classification soil evaluation
下载PDF
企划-活动分类系统的探索性研究
5
作者 李春江 柴彦威 +1 位作者 李彦熙 张艳 《地理研究》 CSSCI CSCD 北大核心 2024年第9期2295-2307,共13页
活动分类是时空间行为研究的基础。社会技术变迁对经典的人类活动分类提出了挑战,基于活动特征的经典分类方法已无法满足当前研究对理解人类活动复杂性与信息通讯技术影响的新需求。时间地理学的企划概念可以弥补当前活动分类的不足。... 活动分类是时空间行为研究的基础。社会技术变迁对经典的人类活动分类提出了挑战,基于活动特征的经典分类方法已无法满足当前研究对理解人类活动复杂性与信息通讯技术影响的新需求。时间地理学的企划概念可以弥补当前活动分类的不足。企划是指为完成特定目标而进行的一系列时空使用。融合企划概念的活动分类强调基于个体或组织意图所构建的活动内在联系来划分活动类型。然而,当前融合企划的活动分类体系还存在企划界定不清、缺乏考虑信息通讯技术发展、以西方发达国家为背景等局限。本研究提出“企划-活动分类系统”的概念、框架和构建方法,并以2021年北京市清河街道社区居民日常活动调查数据为基础,探索构建了企划-活动分类系统。企划-活动分类系统包括“需求-企划-活动-行为-片段”等五个等级,明确了企划在城市活动系统中的位置,链接了从活动需求到活动结果的全过程,在对活动类型进行概括的同时也保留了具体活动的丰富语义和情境信息。基于一手调查数据初步构建的企划-活动分类系统,一方面体现了近年来信息通讯技术发展对日常活动的影响,另一方面展现了具有中国特色的城市活动类型,在人类活动分类的理论方法发展和实证应用等方面显示出不断创新的可能性。 展开更多
关键词 时间地理学 人类活动分类 企划 企划-活动系统 信息通讯技术
原文传递
A SPATIAL CLUSTER METHOD SUPPORTED BY GIS FOR URBAN-SUBURBAN-RURAL CLASSIFICATION 被引量:4
6
作者 ZHOUDe-min XUJian-chun +1 位作者 JohnRADKE MULan 《Chinese Geographical Science》 SCIE CSCD 2004年第4期337-342,共6页
This study was undertaken to construct a preliminary spatial analysis method for building an urban-suburban-rural category in the specific sample area of central California and providing distribution characteristics i... This study was undertaken to construct a preliminary spatial analysis method for building an urban-suburban-rural category in the specific sample area of central California and providing distribution characteristics in each category, based on which, some further studies such as regional manners of residential wood burning emission (PM2.5, the term used for a mixture of solid particles and liquid droplets found in the air, refers to particulate matter that is 2.5 mu m or smaller in size) could be carried out for the project of residential wood combustion. Demographic and infrastructure data with spatial characteristics were processed by integrating both Geographic Information System (GIS) and statistics method (Cluster Analysis), and then output to a category map as the result. It approached the quantitative and multi-variables description on the major characteristics variations among the urban, suburban and rural; and perfected the TIGER's urban-rural classification scheme by adding suburban category. Based on the free public GIS data, the spatial analysis method provides an easy and ideal tool for geographic researchers, environmental planners, urban/regional planners and administrators to delineate different categories of regional function on the specific locations and dig out spatial distribution information they wanted. Furthermore, it allows for future adjustment on some parameters as the spatial analysis method is implemented in the different regions or various eco-social models. 展开更多
关键词 GIS cluster analysis PM2.5 census tract urban-suburban-rural classification
下载PDF
A fuzzy logic resource allocation and memory cell pruning based artificial immune recognition system
7
作者 邓泽林 谭冠政 +1 位作者 何锫 叶吉祥 《Journal of Central South University》 SCIE EI CAS 2014年第2期610-617,共8页
In order to improve the resource allocation mechanism of artificial immune recognition system(AIRS) and decrease the memory cells,a fuzzy logic resource allocation and memory cell pruning based AIRS(FPAIRS) is propose... In order to improve the resource allocation mechanism of artificial immune recognition system(AIRS) and decrease the memory cells,a fuzzy logic resource allocation and memory cell pruning based AIRS(FPAIRS) is proposed.In FPAIRS,the fuzzy logic is determined by a parameter,thus,the optimal fuzzy logics for different problems can be located through changing the parameter value.At the same time,the memory cells of low fitness scores are pruned to improve the classifier.This classifier was compared with other classifiers on six UCI datasets classification performance.The results show that the accuracies reached by FPAIRS are higher than or comparable to the accuracies of other classifiers,and the memory cells decrease when compared with the memory cells of AIRS.The results show that the algorithm is a high-performance classifier. 展开更多
关键词 artificial immune recognition system fuzzy logic memory cell pruning CLASSIFICATION
下载PDF
Single nucleotide polymorphisms in the human corticosteroid-binding globulin promoter alter transcriptional activity 被引量:1
8
作者 LI Yue WU Liang +4 位作者 LEI JingHui ZHU Cheng WANG HongMei YU XiaoGuang LIN HaiYan 《Science China(Life Sciences)》 SCIE CAS 2012年第8期699-708,共10页
Corticosteroid-binding globulin(CBG) is a high-affinity plasma protein that transports glucocorticoids and progesterone.Others and we have reported non-synonymous single nucleotide polymorphisms(SNPs) that influence C... Corticosteroid-binding globulin(CBG) is a high-affinity plasma protein that transports glucocorticoids and progesterone.Others and we have reported non-synonymous single nucleotide polymorphisms(SNPs) that influence CBG production or steroid-binding activity.However,no promoter polymorphisms affecting the transcription of human CBG gene(Cbg) have been reported.In the present study we investigated function implications of six promoter SNPs,including 26 C/G,54 C/T,144 G/C,161 A/G,205 C/A,and 443/444 AG/,five of which are located within the first 205 base pairs of 5'-flanking region and close to the highly conserved footprinted elements,TATA-box,or CCAAT-box.Luciferase reporter assays demonstrated that basal activity of the promoter carrying 54 T or 161 G was significantly enhanced.The first three polymorphisms,26 C/G,54 C/T,and 144 G/C located close to the putative hepatic nuclear factor(HNF) 1 binding elements,altered the transactivation effect of HNF1.We also found a negative promoter response to dexamethasone-activated glucocorticoid receptor(GR),although none of the SNPs affected its transrepression function.Our results suggest that human Cbg 26 C/G,54 C/T,144 G/C,and 161 A/G promoter polymorphisms alter transcriptional activity,and further studies are awaited to explore their association with physiological and pathological conditions. 展开更多
关键词 corticosteroid-binding globulin single nucleotide polymorphism hepatic nuclear factor 1
原文传递
Recent advances in target identification by natural product based chemical probes
9
作者 Benke Hong Ting Dong Xiaoguang Lei 《Science China Chemistry》 SCIE EI CAS CSCD 2016年第9期1088-1092,共5页
Natural products have been extensively used to treat diseases throughout human history. These are mainly because natural products normally target biological macromolecules selectively. Target identification could help... Natural products have been extensively used to treat diseases throughout human history. These are mainly because natural products normally target biological macromolecules selectively. Target identification could help us to develop new therapeutic agents and discover new biological pathways underlying human diseases. Herein, we highlight some recent examples of using natural products and their derivatives as chemical probes to identify the molecular targets and elucidate mode of action. 展开更多
关键词 natural product chemical probe chemical biology target ID
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部