期刊文献+
共找到9篇文章
< 1 >
每页显示 20 50 100
MED结合分层模糊熵在刮板输送机故障识别中的应用
1
作者 王林生 王伟 《煤矿机械》 2021年第2期162-164,共3页
对刮板输送机进行故障识别可保障刮板输送机实现快速故障定位与维修,减少故障维修带来的经济损失。对刮板输送机故障类型进行分类,以表征各个易损部件状态的参数作为故障诊断的输入信号,构建基于最小熵解卷积(MED)和分层模糊熵的刮板输... 对刮板输送机进行故障识别可保障刮板输送机实现快速故障定位与维修,减少故障维修带来的经济损失。对刮板输送机故障类型进行分类,以表征各个易损部件状态的参数作为故障诊断的输入信号,构建基于最小熵解卷积(MED)和分层模糊熵的刮板输送机故障诊断模型。分析基于MED结合分层模糊熵的刮板输送机故障诊断流程,对比采用MED、分层模糊熵和MED结合分层模糊熵算法在不同样本集中的准确率。结果表明,采用MED结合分层模糊熵得到的诊断结果准确率更高且更为稳定,在复杂结构的故障诊断中表现出明显的优势。 展开更多
关键词 刮板输送机 MED 分层模糊 故障诊断 MATLAB
下载PDF
基于熵和支持向量机的病态嗓音识别 被引量:1
2
作者 赵冰心 胡维平 《中国生物医学工程学报》 CAS CSCD 北大核心 2013年第5期546-552,共7页
为了更好地分析实际短数据带噪的病态嗓音信号,利用近年来提出的样本熵、多尺度熵、模糊熵和分层熵的方法来提取嗓音的熵特征参数,并借鉴分层分解方法,提出分层多尺度熵和分层模糊熵,分别对测试集39例正常嗓音和36例病态嗓音进行支持向... 为了更好地分析实际短数据带噪的病态嗓音信号,利用近年来提出的样本熵、多尺度熵、模糊熵和分层熵的方法来提取嗓音的熵特征参数,并借鉴分层分解方法,提出分层多尺度熵和分层模糊熵,分别对测试集39例正常嗓音和36例病态嗓音进行支持向量机(SVM)识别。实验结果表明:三层分层熵、分层多尺度熵、分层模糊熵的识别率和稳定性均较分层前有提高。在耗时较短的情况下,提取2 000点病理嗓音数据的6种熵特征都能达到较好且较稳定的识别率。提取2 000点病理嗓音数据的三层分层模糊熵特征,能得到较好且较稳定的SVM识别率97.33%,较分层前的模糊熵特征识别率提高约4.00%。熵分析方法可推进病态嗓音研究向临床的应用,为临床分析诊断实时、短数据的带噪病理嗓音提供一定的参考。 展开更多
关键词 病态嗓音 模糊 分层熵 支持向量机
下载PDF
Application of combination weighting method in contract risk's evaluation of third party logistics 被引量:3
3
作者 傅新平 邹敏 《Journal of Southeast University(English Edition)》 EI CAS 2007年第S1期128-132,共5页
First,the analytical hierarchy process(AHP),which stands for the subjective weighting method,and the entropy method,which stands for the objective weighting method,are chosen to calculate the index weights of the cont... First,the analytical hierarchy process(AHP),which stands for the subjective weighting method,and the entropy method,which stands for the objective weighting method,are chosen to calculate the index weights of the contract risks of third party logistics(TPL),respectively.Then,they can determine the combination weights using the combination weighting method.Second,using the combination weights,the contract risks of TPL are evaluated through the fuzzy comprehensive evaluation method.According to the combination weights,the most important risk factor of the contract risks of TPL is choosing sub-contractors.The results are basically consistent with the facts and show that the weights determined by the combination weighting method can avoid the man-made deviations of the subjective weighting method on the one hand,and prevent results opposite to the reality brought about by the objective weighting method on the other hand.Meanwhile,the results of the fuzzy comprehensive evaluation are that the contract risks of TPL are at a high risk level.Roughly this matches real situations,and it indicates that the combination weighting method can generate the comprehensive assessment more scientifically and more reasonably as well. 展开更多
关键词 analytical hierarchy process(AHP) entropy method combination weighting method contract risk
下载PDF
Video segmentation using Maximum Entropy Model
4
作者 秦莉娟 庄越挺 +1 位作者 潘云鹤 吴飞 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第B08期47-52,共6页
Detecting objects of interest from a video sequence is a fundamental and critical task in automated visual surveillance. Most current approaches only focus on discriminating moving objects by background subtraction wh... Detecting objects of interest from a video sequence is a fundamental and critical task in automated visual surveillance. Most current approaches only focus on discriminating moving objects by background subtraction whether or not the objects of interest can be moving or stationary. In this paper, we propose layers segmentation to detect both moving and stationary target objects from surveillance video. We extend the Maximum Entropy (ME) statistical model to segment layers with features, which are collected by constructing a codebook with a set of codewords for each pixel. We also indicate how the training models are used for the discrimination of target objects in surveillance video. Our experimental results are presented in terms of the success rate and the segmenting precision. 展开更多
关键词 Layers segmentation Maximum Entropy Model Visual surveillance
下载PDF
基于层次熵权和AHP方法的灾害应急演练综合评价 被引量:5
5
作者 易涛 朱群雄 《计算机与应用化学》 CAS CSCD 北大核心 2014年第4期401-405,共5页
针对应急救援的特殊性(主观性与客观性、确定性与不确定性的混合),为实现应急演练过程与结果的有效评价,建立了一种主客观混合的层次评价体系。首先,分析"负面事件"信息熵和复杂网络各项测度等应急演练评价指标的合理性,指出... 针对应急救援的特殊性(主观性与客观性、确定性与不确定性的混合),为实现应急演练过程与结果的有效评价,建立了一种主客观混合的层次评价体系。首先,分析"负面事件"信息熵和复杂网络各项测度等应急演练评价指标的合理性,指出应急演练评价的特殊性。用传统单一评价方法已经无法满足需求。其次,在分析经典熵权法不足的基础上,构造并分析了层次熵权法并给出核心的算法步骤;分析了层次熵权法和AHP方法的优缺点和各自的特点,并构造了基于层次熵权法和AHP方法的混合评价体系模型、给出了融合算法中修正值的计算方法。最后,运用本文提出的方法对化工厂应急演练中各项指标进行分析建模,通过一个应用案例证明了该混合评价方法的可行性与有效性。本文为应急演练过程与结果的有效评价提供新的方法。 展开更多
关键词 分层熵权评价法 AHP分析法 灾害复杂网络测度 应急演练 综合评价
原文传递
Residents'Satisfaction with Public Services in Mountainous Areas:An Empirical Study of Southwestern Sichuan Province,China 被引量:4
6
作者 SONG Xueqian DENG Wei +2 位作者 LIU Ying ZHAO Chen WAN Jiangjun 《Chinese Geographical Science》 SCIE CSCD 2017年第2期311-324,共14页
Abstract: Enhancing the efficiency of public services is essential to residents in mountainous areas. It is also important to promote sus- tainable development of these regions. Analysing residents' satisfaction wit... Abstract: Enhancing the efficiency of public services is essential to residents in mountainous areas. It is also important to promote sus- tainable development of these regions. Analysing residents' satisfaction with public services in mountainous areas can help in evaluating outcomes of fiscal investment and identifying potential coping approaches for improving public service efficiencies. The residents' satisfaction with public services and the factors that influence such satisfaction were examined in this study. A study of 12 towns located in the southwestern Sichuan Province was performed using an entropy-weighted analytic hierarchy process (EWAHP), the technique for order preference by similarity to ideal solution (TOPSIS) and Tobit regression methods. The results indicate that: 1) the spatial distribu- tion of satisfaction with public services is non-uniform, and the spatial distribution structure varies for different types of public services. 2) Residents' satisfaction with public services is influenced by both objective and subjective factors. Population density, economic dis- tance, social and cultural divisions and elevation are the major objective factors, whereas bounded rationality, the hierarchy of needs and service expectations are the main subjective factors. The most effective strategies for enhancing residents' satisfaction with public ser- vices are likely to be clustering the population, choosing supply centres with different public services, regulating the cultural division in ethnic minority towns, selecting supply priorities in accordance with residents' needs, implementing targeted intervention policies and establishing 'bottom-up' and 'top-down' integrated decision-making mechanisms. Keywords: mountainous areas; public services; residents' satisfaction; entropy-weighted analytic hierarchy process (EWAHP); technique for order preference by similarity to ideal solution (TOPSIS); Tobit regression; southwestern Sichuan Province 展开更多
关键词 mountainous areas public services residents' satisfaction entropy-weighted analytic hierarchy process (EWAHP) technique for order preference by similarity to ideal solution (TOPSIS) Tobit regression southwestern Sichuan Province
下载PDF
基于粗糙粒模型的图像纹理识别和检索 被引量:4
7
作者 徐久成 李晓艳 +1 位作者 张灵均 李双群 《模式识别与人工智能》 EI CSCD 北大核心 2012年第2期225-229,共5页
传统的纹理识别方法大多是对图像频谱的研究,文中尝试以粒计算理论为基础,利用分层思想对图像的纹理特征进行识别.首先,通过引入粒的边缘和分层熵的概念,建立粗糙粒理论,构造粗糙粒度空间模型.然后,构建基于粒的边缘和分层熵的相似度计... 传统的纹理识别方法大多是对图像频谱的研究,文中尝试以粒计算理论为基础,利用分层思想对图像的纹理特征进行识别.首先,通过引入粒的边缘和分层熵的概念,建立粗糙粒理论,构造粗糙粒度空间模型.然后,构建基于粒的边缘和分层熵的相似度计算方法,得出一种图像纹理识别方法.该方法不仅提高模型在图像纹理识别上的实用性,而且通过对识别和检索过程的同步进行简化纹理识别的计算过程.最后,仿真实验表明,该模型及所用到的相关方法是可行的,与其它方法相比,该方法识别和检索效果较好. 展开更多
关键词 粗糙粒 粒的边缘 分层熵 纹理识别
原文传递
Evaluating the Ecological Security of Land Resources based on Multi-source Data in the Altay Region of China 被引量:1
8
作者 YE Hui BAI Die +2 位作者 TAN Shucheng SHAO Dajiang WANG Jinliang 《Journal of Resources and Ecology》 CSCD 2021年第6期757-765,共9页
As a material carrier contributing to human survival and social sustainable development,the ecological environment is declining in its integrity and overall health.With the rapid development of society and economy,it ... As a material carrier contributing to human survival and social sustainable development,the ecological environment is declining in its integrity and overall health.With the rapid development of society and economy,it is currently very necessary to carry out ecological security evaluation research to provide scientific guidance and suggestions for the construction of ecological civilization and the harmonious co-existence between man and nature.Taking Altay region as the research area,this paper collected and integrated regional geological,geographical,cultural,socio-economic,and statistical data,as well as previous research results.Combined with DPSIR and EES framework model,the evaluation index system of land resource ecological security in Altay region was constructed by using the analytic hierarchy process,entropy method and linear weighted summation function method.Using this index system,the evaluation research work was carried out to determine the current state of the security situation and the major threats which should be addressed.(1)The overall ecological security situation of Altay region was relatively safe,while the local ecological security situation was relatively fragile.Among them,the areas with safe and safer ecological environment accounted for 38.72%,while the areas with critically safe status accounted for 30.83%,and the areas with a less safe and unsafe environment accounted for 30.45%.In terms of spatial characteristics,the areas with unsafe ecological environment were mainly distributed in the west and east of the study area,while the areas with good ecological environment were distributed in the north of the study area.(2)Large-scale mining activities,frequent geological disasters,large-scale reclamation and long-term cultivation of arable land,and long-term large-scale grazing activities resulting in the destruction of grassland and vegetation were the main factors leading to the prominent ecological security problems of land resources in the Altay region.Therefore,in the process of the continuous development of the urban economy,we should pay more attention to the harmony between man and nature,and also actively and effectively advocate and implement certain policies and measures,such as returning farmland to forest,returning grazing land to grassland and integrating the mining of mineral resources. 展开更多
关键词 land ecological security evaluation DPSIR-EES model analytic hierarchy process entropy value method Altay region
原文传递
Tailored microstructures and strengthening mechanisms in an additively manufactured dualphase high-entropy alloy via selective laser melting 被引量:7
9
作者 Shuncun Luo Yue Su Zemin Wang 《Science China Materials》 SCIE EI CSCD 2020年第7期1279-1290,共12页
Dual-phase high-entropy alloys(DP-HEAs)with excellent strength-ductility combinations have attracted scientific interests.In the present study,the microstructures of AlCrCuFeNi3.0DP-HEA fabricated via selective laser ... Dual-phase high-entropy alloys(DP-HEAs)with excellent strength-ductility combinations have attracted scientific interests.In the present study,the microstructures of AlCrCuFeNi3.0DP-HEA fabricated via selective laser melting(SLM)are rationally adjusted and controlled.The mechanisms engendering the hierarchical microstructures are revealed.It is found that the AlCrCuFeNi3.0fabricated by SLM at the scanning speed of 400 mm s-1falls into the eutectic coupled zone,and increasing the scanning speed will make this composition deviate away from the eutectic coupled zone due to the increased cooling rate.The enrichment of Cr and Fe solutes with large growth restriction values ahead of the solid/liquid interface can develop a constitutional supercooling zone,thus facilitating the heterogeneous nucleation and nearequiaxed grain formation.The synergy of the near-eutectic DP nano-structures and near-equiaxed grains instead of columnar ones effectively suppresses cracking for the as-built DP-HEA.During the tensile deformation,the intergranular back stress hardening similar to the grain-boundary strengthening is discovered.Meanwhile,the near-eutectic microstructures comprised of soft face-centered cubic and hard ordered bodycentered cubic(B2)DP nano-structures lead to plastic strain incompatibility within grains,thus producing the intragranular back stress.The Cr-rich nano-precipitates inside the B2 phase are found to be sheared by dislocation gliding and can complement the back stress.Additionally,multiple strengthening mechanisms are physically evaluated,and the back stress strengthening contributes obviously to the high performances of the as-built DP-HEA. 展开更多
关键词 high-entropy alloy selective laser melting hierarchical microstructures back stress strengthening mechanism
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部