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Application of extension neural network to safety status pattern recognition of coalmines 被引量:6
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作者 周玉 W.Pedrycz 钱旭 《Journal of Central South University》 SCIE EI CAS 2011年第3期633-641,共9页
In order to accurately and quickly identify the safety status pattern of coalmines,a new safety status pattern recognition method based on the extension neural network (ENN) was proposed,and the design of structure of... In order to accurately and quickly identify the safety status pattern of coalmines,a new safety status pattern recognition method based on the extension neural network (ENN) was proposed,and the design of structure of network,the rationale of recognition algorithm and the performance of proposed method were discussed in detail.The safety status pattern recognition problem of coalmines can be regard as a classification problem whose features are defined in a range,so using the ENN is most appropriate for this problem.The ENN-based recognition method can use a novel extension distance to measure the similarity between the object to be recognized and the class centers.To demonstrate the effectiveness of the proposed method,a real-world application on the geological safety status pattern recognition of coalmines was tested.Comparative experiments with existing method and other traditional ANN-based methods were conducted.The experimental results show that the proposed ENN-based recognition method can identify the safety status pattern of coalmines accurately with shorter learning time and simpler structure.The experimental results also confirm that the proposed method has a better performance in recognition accuracy,generalization ability and fault-tolerant ability,which are very useful in recognizing the safety status pattern in the process of coal production. 展开更多
关键词 safety status pattern recognition extension neural network coal mines
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A reliability evaluation method for embryonic cellular array based on Markov status graph model 被引量:2
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作者 WANG Tao CAI Jinyan +1 位作者 MENG Yafeng ZHU Sai 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第2期432-446,共15页
Due to the limitations of the existing fault detection methods in the embryonic cellular array(ECA), the fault detection coverage cannot reach 100%. In order to evaluate the reliability of the ECA more accurately, emb... Due to the limitations of the existing fault detection methods in the embryonic cellular array(ECA), the fault detection coverage cannot reach 100%. In order to evaluate the reliability of the ECA more accurately, embryonic cell and its input and output(I/O) resources are considered as a whole, named functional unit(FU). The FU fault detection coverage parameter is introduced to ECA reliability analysis, and a new ECA reliability evaluation method based on the Markov status graph model is proposed.Simulation experiment results indicate that the proposed ECA reliability evaluation method can evaluate the ECA reliability more effectively and accurately. Based on the proposed reliability evaluation method, the influence of parameters change on the ECA reliability is studied, and simulation experiment results show that ECA reliability can be improved by increasing the FU fault detection coverage and reducing the FU failure rate. In addition, by increasing the scale of the ECA, the reliability increases to the maximum first, and then it will decrease continuously. ECA reliability variation rules can not only provide theoretical guidance for the ECA optimization design, but also point out the direction for further research. 展开更多
关键词 EMBRYONIC MARKOV status graph model RELIABILITY FAULT detection evaluation
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Dataset of human motion status using IR-UWB through-wall radar 被引量:3
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作者 ZHU Zhengliang YANG Degui +1 位作者 ZHANG Junchao TONG Feng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第5期1083-1096,共14页
Ultra-wideband(UWB)through-wall radar has a wide range of applications in non-contact human information detection and monitoring.With the integration of machine learning technology,its potential prospects include the ... Ultra-wideband(UWB)through-wall radar has a wide range of applications in non-contact human information detection and monitoring.With the integration of machine learning technology,its potential prospects include the physiological monitoring of patients in the hospital environment and the daily monitoring at home.Although many target detection methods of UWB through-wall radar based on machine learning have been proposed,there is a lack of an opensource dataset to evaluate the performance of the algorithm.This published dataset is measured by impulse radio UWB(IR-UWB)through-wall radar system.Three test subjects are measured in different environments and several defined motion status.Using the presented dataset,we propose a human-motion-status recognition method using a convolutional neural network(CNN),and the detailed dataset partition method and the recognition process flow are given.On the well-trained network,the recognition accuracy of testing data for three kinds of motion status is higher than 99.7%.The dataset presented in this paper considers a simple environment.Therefore,we call on all organizations in the UWB radar field to cooperate to build opensource datasets to further promote the development of UWB through-wall radar. 展开更多
关键词 impulse radio ultra-wideband(IR-UWB) through-wall radar human motion status DATASET convolutional neural network(CNN)
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The Status Quo and Development Trend of High-purity Gold Sputtering Targets 被引量:1
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作者 YANG Anheng XIE Hongchao ZHU Yong 《贵金属》 CAS CSCD 北大核心 2012年第A01期173-176,共4页
This article gives a brief introduction to manufacturers and markets of sputtering targets as well as the manufacturing technology thereof. Then, it analyzes the application of high-purity gold sputtering targets in t... This article gives a brief introduction to manufacturers and markets of sputtering targets as well as the manufacturing technology thereof. Then, it analyzes the application of high-purity gold sputtering targets in the fields of integrated circuit, information storage, flat panel display, etc. Based on the above, the article analyzes the processing development trend for the high-purity gold sputtering targets in aspects of ultra-high purity, manufacturing technology, analysis and testing technologies. 展开更多
关键词 high-purity gold sputtering targets status quo development trend
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Complete Sequence of Yak Mitochondrial D-loop Region and Its Taxonomic Status in Bovinae
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作者 LI Qi-fa LI Yin-xia +4 位作者 DONG Li-yan ZHAO Xing-bo PAN Zeng-xiang LI Ning XIE Zhuang 《畜牧兽医学报》 CAS CSCD 北大核心 2009年第S1期18-22,共5页
Primers based upon the mitochondrial genome sequences of Bos taurus were used to amplify and sequence the complete mitochondrial D-loop region of Jiulong yak(Poephagus grunniens).The results showed that the length of ... Primers based upon the mitochondrial genome sequences of Bos taurus were used to amplify and sequence the complete mitochondrial D-loop region of Jiulong yak(Poephagus grunniens).The results showed that the length of D-loop was 893 bp,with 87.4%homology to the Bos taurus D-loop sequence;there were 17 bp deletion.Using Ovis aries as an outgroup,the phylogeny of representative species of Bovinae(P.grunniens,P.mutus,Bos taurus,Bos indicus,Bison bison,Bison bonasus,and Bubalus bubalis)was analyzed.Among Bovinae,the sequence divergence between P.grunniens,P.mutus and American bison(Bison bison)was 6.2%-6.8%,which was less than that of Bos taurus and Bos indicus within Bos(10.0%-11.3%).Phylogenetic analysis found that P.grunniens,P.mutus and Bison bison clustered first of all,indicating there was higher genetic comparability among them than to that of Bos.Combining data from paleontology,morphology,and molecular biology,the present analysis supports the argument that Poephagus grunniens and Poephagus mutus should be classified as a distinct genus in Bovinae,that is Poephagus. 展开更多
关键词 Bovinae Poephagus yak(Poephagus grunniens) D-LOOP PHYLOGENETIC relationship TAXONOMIC status
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Research of the Plastic Status Parameter and Instantaneous Clearance of a Punching Without Urr
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作者 LI Jian-hua, DU Hong, NIU Yong-sheng, FU Xiao-li (Department of Mechanical Engineering, Zhongyuan Institute of Technology, Zhengzhou 450007, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期54-55,共2页
The article mainly talks about the characteristic of common and fine punching and the quality of shearing edge. Although the common punching has been widely applied, the quality of shearing edge is very poor. The fine... The article mainly talks about the characteristic of common and fine punching and the quality of shearing edge. Although the common punching has been widely applied, the quality of shearing edge is very poor. The fine punching work-piece is better in quality. But it isn’t still been widely applied, because the structure of die is complicated and the manufacture of die and using pressure machine are expensive. A new fine punching processing without burr is put forward by discussing the plastic status and press stress status of the material which influence the quality of the punching work-piece in the deformation zone, it provides the plastic status of material to determine the parameter in the new processing and presents the maximum value of plastic deformation specific energy when the material reaches the plastic status. The author has analyzed the initializing clearance and instantaneous clearance of the ordinary punching. The instantaneous clearance of the ordinary punching process is instable. By studying the author brings forward a kind of punching process which initializing clearance and instantaneous clearance are stable, that is the negative clearance fine punching process. Because of using the negative clearance fine punching process, the material of sheared distorting section comes into the plastic state. The surface quality of the punching sheared edge is advanced 1.5 times than that of the ordinary punching. The recommended value of depth of the negative clearance punching has been given in this article. 展开更多
关键词 PUNCHING plastic status PARAMETER instantaneous clearance
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The present status of infectious diseases of laboratory animals in Bangladesh
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作者 Abdul Awal 《中国实验动物学报》 CAS CSCD 2005年第S1期18-,共1页
关键词 The present status of infectious diseases of laboratory animals in Bangladesh
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What kind of cotton ideotype is adapted to agroecological cropping systems and climate change in Benin?
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作者 ABOUA Dègbédji Charlemagne GÉRARDEAUX Edward +2 位作者 DEBAEKE Philippe BOULAKIA Stéphane SEKLOKA Emmanuel 《Journal of Cotton Research》 2025年第3期319-332,共14页
Background Agroecological cropping systems are recognised as an alternative way to ensure the sustainability of cotton(Gossypium hirsutum L.) production in the context of climate change and degradation of soil fertili... Background Agroecological cropping systems are recognised as an alternative way to ensure the sustainability of cotton(Gossypium hirsutum L.) production in the context of climate change and degradation of soil fertility. A study was conducted in Benin from 2020 to 2023 to compare six different cotton cultivars in three agroecological cropping systems in two cotton-growing zones. Plough-based tillage plus incorporation of cover crop biomass(PTI), conservation agriculture with strip tillage(CA_ST), and conservation agriculture with no tillage(CA_NT) were compared with the reference plough-based tillage(PT). The objective was to identify morpho-physiological traits of cotton that increase yield in agroecological cropping systems. Our approach combined a field experiment and crop simulation model(CSM) of CROPGRO-Cotton to evaluate the effects of genotype(G) × environment(E) × management(M) interactions on seed cotton yield(SCY).Results Cultivars Tamcot_camde and Okp768 and simulated ideotypes performed best in CA systems. Increased seed mass, large and thick leaves, and later maturity were identified as beneficial for yield enhancement in CA systems. Cultivars and ideotypes that combine these traits also resulted in better nitrogen and water use efficiencies in CA systems. Under different climate scenarios up to 2050, ideotypes designed could increase SCY in Benin.Conclusion A set of morpho-physiological traits associated with vegetative vigour is required to ensure a good SCY in agroecological cropping systems. These results provide scientific evidence and useful knowledge for breeders and research programmes on cropping systems focused on the adaptation of cotton to climate change. 展开更多
关键词 TILLAGE Agroecological practices Water status Gossypium hirsutum IDEOTYPE Seed cotton yield Cover crop CSM-CROPGRO-Cotton
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城市森林规划的现状与发展 被引量:8
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作者 刘滨谊 温全平 刘颂 《中国城市林业》 2008年第1期16-21,共6页
分析了城市森林规划在中国发展的背景,通过案例分析,总结比较了英美两国城市森林规划的特点以及中国城市森林规划的特点,从城市森林规划的范围、与城市绿地系统规划的关系、规划对象、内容、方法、城市森林的多功能问题、协调问题、规... 分析了城市森林规划在中国发展的背景,通过案例分析,总结比较了英美两国城市森林规划的特点以及中国城市森林规划的特点,从城市森林规划的范围、与城市绿地系统规划的关系、规划对象、内容、方法、城市森林的多功能问题、协调问题、规划实施和规划立法九个方面探讨了中国城市森林规划的发展。 展开更多
关键词 URBAN FOREST PLANNING CURRENT status Development
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烤烟连作对重庆土壤养分状况的影响 被引量:19
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作者 苏海燕 程传策 +3 位作者 马啸 罗晓庆 李常军 阳波 《河南农业科学》 CSCD 北大核心 2010年第12期59-62,共4页
通过田间取样和室内分析相结合的方法,调查研究了重庆市石柱、奉节和南川3个县烤烟连作土壤的养分状况。结果表明:烟田连作后土壤pH值下降,相邻茬次之间平均下降0.05,土壤酸化;有机质含量逐年下降,相邻茬次之间平均衰减0.56%g/kg;全氮... 通过田间取样和室内分析相结合的方法,调查研究了重庆市石柱、奉节和南川3个县烤烟连作土壤的养分状况。结果表明:烟田连作后土壤pH值下降,相邻茬次之间平均下降0.05,土壤酸化;有机质含量逐年下降,相邻茬次之间平均衰减0.56%g/kg;全氮、全磷、全钾含量随连作年限延长表现出不同程度的升高趋势,表现为P(6%~31%)>K(6%~21%)>N(2%~12%);速效磷、速效钾含量随连作年限延长逐年降低,且降低程度P(6%~24%)>K(2%~10%),速效氮含量略有上升;速效养分N/P、N/K和K/P比值明显增加,土壤养分比例失调。 展开更多
关键词 烤烟连作 重庆市 土壤养分状况 Soil Nutrient status 连作年限 有机质含量 速效钾含量 土壤酸化 速效养分 全钾含量 连作土壤 调查研究 比例失调 速效磷 内分析 氮含量 田间 衰减 石柱 升高
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济源烟区土壤营养状况评价研究 被引量:4
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作者 苏志军 乔中兴 +5 位作者 薛立新 杨红 谢晓辉 吴群 金磊 景延秋 《江西农业学报》 CAS 2010年第8期67-70,共4页
对济源市烤烟主产区植烟土壤的营养现状进行了分析,取样地点126个,覆盖了全市4个烟区(邵原、王屋、下冶和大峪)的植烟土壤。结果表明:济源烟区土壤总氮、碱解氮、有机质含量较适宜;个别地区速效磷、有效锌含量较低;水溶性氯含量均在合... 对济源市烤烟主产区植烟土壤的营养现状进行了分析,取样地点126个,覆盖了全市4个烟区(邵原、王屋、下冶和大峪)的植烟土壤。结果表明:济源烟区土壤总氮、碱解氮、有机质含量较适宜;个别地区速效磷、有效锌含量较低;水溶性氯含量均在合理范围;有效硼含量则明显不足;速效钾含量则比较丰富,在豫西乃至河南烟区都处于较高水平。 展开更多
关键词 烟区土壤 土壤营养状况 评价研究 Flue-cured Tobacco Nutrition status Evaluation 植烟土壤 有效硼含量 有机质含量 速效钾含量 营养现状 合理范围 主产区 锌含量 速效磷 水溶性 氯含量 碱解氮 济源市 高水平
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浅析20世纪美国妇女社会地位的变化(英文)
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作者 佟晓牧 《思想战线》 CSSCI 北大核心 2011年第S1期468-469,共2页
Traditionally women's primary role should be wives,mothers and homemakers,and today women are still mothers,but few of them stay home full time to take care of the house and children.They never cease their steps t... Traditionally women's primary role should be wives,mothers and homemakers,and today women are still mothers,but few of them stay home full time to take care of the house and children.They never cease their steps to gain equal rights with men.The paper will try to analyze the changes of women's social status in the 20th century,exploring its reasons. 展开更多
关键词 WOMEN SOCIAL status CHANGES
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局部晚期非小细胞肺癌同步放化疗随机对照临床试验 被引量:5
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作者 孙志华 于世英 +1 位作者 刘英杰 王婷 《中国肺癌杂志》 CAS 2005年第6期547-549,共3页
关键词 局部晚期非小细胞肺癌 随机对照临床试验 同步放化疗 NSCLC LC患者 cancer status 序贯放化疗 异长春花碱 cell
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吉林省主要耕作土壤中含钾矿物组成及其与不同形态钾的关系 被引量:10
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作者 刘淑霞 赵兰坡 +2 位作者 李楠 高强 刘会清 《植物营养与肥料学报》 CAS CSCD 北大核心 2002年第1期70-76,共7页
通过化学分析 ,X 射线衍射及镜检法研究了黑土、白浆土、黑钙土等吉林省主要耕作土壤的含钾矿物组成及不同形态钾的含量。结果表明 ,土壤中的含钾矿物以含钾长石和伊利石为主 ,钾长石主要集中在土壤砂粒部分 ,伊利石主要存在于土壤的粘... 通过化学分析 ,X 射线衍射及镜检法研究了黑土、白浆土、黑钙土等吉林省主要耕作土壤的含钾矿物组成及不同形态钾的含量。结果表明 ,土壤中的含钾矿物以含钾长石和伊利石为主 ,钾长石主要集中在土壤砂粒部分 ,伊利石主要存在于土壤的粘粒部分。土壤的含钾矿物总量约占土壤矿物总量的 1/ 3多些 ,比南方土壤高 ;缓效钾含量丰富 ,供钾潜力大 ;速效钾含量在黑土、黑钙土中较高 ,而在白浆土中稍低。 3种土壤的全钾量与含钾矿物总量、粘粒中伊利石含量与粘粒含钾量、伊利石含量与缓效钾量、细砂中含钾长石含量与细砂中全钾量、缓效性钾与速效性钾之间呈极显著或显著相关。 展开更多
关键词 耕作土壤 含钾矿物 钾形态 矿物 吉林
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矿冶工程化学虚拟仿真实验教学中心“四位一体”建设模式的探索与实践 被引量:20
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作者 钟宏 韩响玲 +3 位作者 刘有才 陈国辉 张居华 尹翔 《实验技术与管理》 CAS 北大核心 2014年第9期10-13,共4页
虚拟仿真实验教学可以实现矿冶工程化学类专业真实实验不具备和难以完成的教学功能。中南大学矿冶工程化学虚拟仿真实验教学中心立足学科特点,围绕培养具有扎实基础与优良专业素质拔尖人才的任务,从教学资源的开发、开放共享机制的探索... 虚拟仿真实验教学可以实现矿冶工程化学类专业真实实验不具备和难以完成的教学功能。中南大学矿冶工程化学虚拟仿真实验教学中心立足学科特点,围绕培养具有扎实基础与优良专业素质拔尖人才的任务,从教学资源的开发、开放共享机制的探索、管理运行机制的构建以及保障体系的建设等4个方面,探索了矿冶工程化学虚拟仿真实验教学中心"四位一体"建设模式,具有一定的示范作用以及现实指导意义。 展开更多
关键词 虚拟仿真 实验教学中心 矿冶工程化学 四位一体
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国外屋顶绿化现状与基本经验 被引量:20
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作者 陈景升 何友均 《中国城市林业》 2008年第1期74-76,共3页
在收集国外大量关于屋顶绿化资料,以及实地考察国外屋顶绿化建设的基础上,总结了屋顶绿化的类型和功能。
关键词 Rooftop gardening current status PROBLEMS SOLUTIONS
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生态位理论及其应用研究进展 被引量:119
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作者 林开敏 郭玉硕 《福建林学院学报》 CSCD 北大核心 2001年第3期283-287,共5页
生态位理论是近 2 0 a来生态学研究的热点之一 .对生态位的概念、定义、定量测度方法和应用现状进行综述 ,并分析生态位理论应用中存在问题 ,为种群生态学的深入研究提供科学的理论依据 .
关键词 定量测度方法 应用现状 生态学 生态位理论 生态学重叠 竞争
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医务工作者体育锻炼特征的社会学分析 被引量:6
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作者 侯广斌 李儒新 +1 位作者 李群英 冯明丽 《体育学刊》 CAS 北大核心 2005年第2期40-42,共3页
以湖南、广东两省各级各类医院的医务工作者为研究对象,研究其体育锻炼的特征,结果显示:医务工作者体育锻炼情况与其对体育认知度、文化层次、知识结构、收入水平等明显背离,体育人口比例仅为12.5%;他们在主观上更多的将不能坚持体育锻... 以湖南、广东两省各级各类医院的医务工作者为研究对象,研究其体育锻炼的特征,结果显示:医务工作者体育锻炼情况与其对体育认知度、文化层次、知识结构、收入水平等明显背离,体育人口比例仅为12.5%;他们在主观上更多的将不能坚持体育锻炼归因于精神压力大、累、工作忙等因素;客观上不规律的作息,场地、器材的短缺使他们的体育锻炼难以形成动力定型;他们更多的将食补、睡眠作为消除疲劳、促进健康的主要手段。 展开更多
关键词 医务工作者 体育锻炼 动力定型 余暇时间 身心状态
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基于相关分析和神经网络的激光焊接稳态识别 被引量:7
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作者 黄威威 游德勇 +2 位作者 高向东 张艳喜 黄宇辉 《激光技术》 CAS CSCD 北大核心 2022年第3期312-319,共8页
为了准确识别激光焊接的稳态类型,采用了图像处理、相关分析和神经网络的方法,增加对准稳态的研究,以信号特征的相关系数作为神经网络模型的输入,进行了理论分析和实验验证,得出了光学、视觉信号的相关性对激光焊接稳态类型的影响规律... 为了准确识别激光焊接的稳态类型,采用了图像处理、相关分析和神经网络的方法,增加对准稳态的研究,以信号特征的相关系数作为神经网络模型的输入,进行了理论分析和实验验证,得出了光学、视觉信号的相关性对激光焊接稳态类型的影响规律。结果表明,匙孔面积和金属蒸汽面积的相关性区分稳态类型的效果最好,其相关系数为0.2~0.3时为稳态,0.4~0.5时为准稳态,0.6~0.7时为非稳态;训练完成的神经网络模型在测试集上达到了98.76%的预测准确率,可满足准确识别焊缝稳态类型的需求。该研究为自动化生产中预防出现激光焊接缺陷提供了参考。 展开更多
关键词 激光技术 稳态识别 相关分析 神经网络 图像处理
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散料在锥仓中的静压接触状态与影响因素 被引量:4
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作者 王学文 Qin Yi +2 位作者 李娟莉 Tian Yankang 杨兆建 《农业工程学报》 EI CAS CSCD 北大核心 2015年第16期65-70,共6页
为研究散料属性与锥仓结构对散料与锥仓之间接触状态的影响,建立了自由开接触、滑移闭接触、黏着闭接触等状态的接触条件与数学求解模型;以葵花籽、玉米、煤粉、圆砾石、小麦为实例,进行了散料在不同倾角锥仓中的静压接触状态有限元分析... 为研究散料属性与锥仓结构对散料与锥仓之间接触状态的影响,建立了自由开接触、滑移闭接触、黏着闭接触等状态的接触条件与数学求解模型;以葵花籽、玉米、煤粉、圆砾石、小麦为实例,进行了散料在不同倾角锥仓中的静压接触状态有限元分析,给出了5种散料在倾角分别为20°、33.7°、45°的锥仓中的接触状态。结果显示:散料堆积密度、弹性模量、泊松比、膨胀角、内摩擦角、内聚力等属性对散料在锥仓中的接触状态影响程度不同,其中膨胀角和内聚力有较大影响,膨胀角很小时,可能会有开接触状态,内聚力越大,则黏着接触区越小;锥仓由深向浅过渡时,开接触区域会消失,滑移接触区会变小,黏着接触区会增大。当散料黏着接触区增加时,不利于锥仓卸料;滑移接触区增加则对锥仓表面摩擦损伤大。通过散料在锥仓中的接触状态研究可从力学特性上评价锥仓设计与储料效率。 展开更多
关键词 有限元 接触分析 力学特性 散料 锥仓 接触状态 滑移 黏着 开接触
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