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Periodic-phase-diagram similarity method for weak signal detection

International Journal of Mechanical System Dynamics 2021年第2期1卷 248-255页

作者： Ruilan Tian yangkun Zhang Shaopu Yang Kai Yuan Qiang Xue Quanrong Ren State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuangChina Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuangChina

The periodic-phase-diagram similarity method is proposed to identify the frequency of weak harmonic *** key technology is to find a set of optimal coefficients for Duffing system,which leads to the periodic motion under the influence of weak signal and strong *** the phase diagram similarity,the influences of strong noise on the similarity of periodic phase diagram are *** principle of highest similarity of periodic phase diagram with the same frequency is detected by discussing the persistence of similarity of periodic motion phase diagram under the strong noise and the periodic-phase-diagram similarity method is *** weak signals of early fault and strong noise are input into Duffing system to obtain the identified *** stochastic subharmonic Melnikov method is extended to obtain the conditions of the optimal coefficients for the identified *** on the results,the constructed frequency conversion harmonic weak signals are considered to form a datum periodic *** the change of frequency in the datum periodic system,the phase diagram similarity of the two constructed systems can be *** on the periodic-phase-diagram similarity method,the frequency of weak harmonic signals can be identified by the principle of highest similarity of periodic phase diagram with the same *** results of numerical simulation and the early fault diagnosis results of actual bearings verify the feasibility of the periodic-phase-diagram similarity *** accuracy of the detection effect is 97%,and the minimum signal-to-noise ratio is−80.71 dB.

关键词： periodic system signal-to-noise ratio stochastic subharmonic Melnikov method strong noise weak signal

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Selective catalytic hydrogenation of naphthalene to tetralin over a NiMo/Al2.3 catalyst

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Chinese Journal of Chemical Engineering 2020年第10期28卷 2566-2576页

作者： Xiaoping Su Pu An Junwen Gao RuchengWang Yujuan Zhang Xi Li yangkun Zhao Yongqi Liu Xiaoxun Ma Ming Sun School of Chemical Engineering Northwest UniversityInternational Science&Technology Cooperation Base of MOST for Clean Utilization of Hydrocarbon ResourcesChemical Engineering Research Center of the Ministry of Education for Advanced Use Technology of Shanbei EnergyShaanxi Research Center of Engineering Technology for Clean Coal ConversionCollaborative Innovation Center for Development of Energy and Chemical Industry in Northern ShaanxiXi'an 710069China Shaanxi Yanchang Petroleum(Group)Co. Ltd.Xi'an 710069China

The selective catalytic hydrogenation of naphthalene to high-value tetralin was systematically investigated.A series of Al2.3 catalysts containing different active metals(Co,Mo,Ni,W)were prepared by incipient wetness *** effects of different active metals forms(oxidation,reduction,sulfuration)and reaction conditions on naphthalene hydrogenation were investigated and the catalysts were characterized by XRD,XPS,BET,NH3-TPD and ***,Ni-Mo/Al2.3 was first used in this reactive *** results show that the oxidative4%Ni O-2.%MoO3/Al2.3 is the best catalyst for the preparation of *** conversion of naphthalene and the selectivity of tetralin can reach 95.62.and 99.75%respectively at 2.0℃,8 h and 6 *** with reduced and sulfureted 4%Ni O-2.%MoO3/Al2.3 catalysts,oxidative 4%Ni O-2.%MoO3/Al2.3 has a well dispersed and uniform monolayer of the active metals,larger pore volume and size,and larger total ***-MoO3/Al2.3 has a synergistic effect between NiO activity and MoO3 selectivity.

关键词： Naphthalene Tetralin Ni-Mo/Al2.3 catalysts

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基于主客观组合权重的上下车人机舒适性研究

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汽车零部件 2024年第4期 29-34页

作者：孙阳坤霍灿坚汪孛钟勰华猛华波广州汽车集团股份有限公司汽车工程研究院广东广州511434

汽车上下车人机舒适性直接影响着用户的日常使用体验。为研究上下车人机舒适性各细分区域的重要程度,列出主要影响因素,首先,扫描试验车辆,逆向出每台车的人体位置设计数据,从而获得客观数据,对客观数据进行皮尔逊相关分析,利用熵权法... 详细信息

汽车上下车人机舒适性直接影响着用户的日常使用体验。为研究上下车人机舒适性各细分区域的重要程度,列出主要影响因素,首先,扫描试验车辆,逆向出每台车的人体位置设计数据,从而获得客观数据,对客观数据进行皮尔逊相关分析,利用熵权法得到指标客观权重;其次,基于主观评价数据的线性回归及专家评价的层次分析法获得主观权重,利用权重因子法得到各指标最终的主观得分,并将其作为训练集来组合优化主观权重;最后,基于组合权重法将主观权重与客观权重相结合获得综合权重。结果表明,提供的主客观评价体系有较高的可靠性,可被较好地用于上下车人机舒适性的早期规划和后期设计、验证。

关键词：上下车人机舒适性权重因子法线性回归层次分析熵权法组合权重法

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基于GIS技术的荔波县生态敏感性评价

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南方农业 2024年第2期18卷 123-126页

作者：智扬坤柳华富黄小祥姚成林贵州华旭林业勘察设计有限公司贵州贵阳550009 贵州茂兰国家级自然保护区管理局贵州荔波558400

从自然资源、地形地貌、社会因素3方面选取5个生态因子构建评价指标体系,结合层次分析法和地理信息系统(Geographic Information System,GIS),对贵州省荔波县生态敏感性进行综合分析与评价。结果表明:荔波县整体生态敏感性较高,主要受... 详细信息

从自然资源、地形地貌、社会因素3方面选取5个生态因子构建评价指标体系,结合层次分析法和地理信息系统(Geographic Information System,GIS),对贵州省荔波县生态敏感性进行综合分析与评价。结果表明:荔波县整体生态敏感性较高,主要受自然保护地的影响,集中分布在自然资源和生物多样性丰富、植被覆盖度高的区域。荔波县综合生态敏感性由低到高分为5个敏感等级,其中不敏感区面积364.8731 hm^(2.,占评价总面积的15.08%;轻度敏感区面积407.4514 hm^(2.,占16.84%;中度敏感区面积572.6389 hm^(2.,占2..67%;高度敏感区面积42..6088 hm^(2.,占17.51%;极度敏感区面积650.7186 hm^(2.,占2..90%。

关键词：生态敏感性 GIS技术层次分析法贵州省荔波县

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The new discovery of Oligocene cyprinidae fossil in Qaidam basin, Northwest China

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Acta Geologica Sinica(English Edition) 2017年第S1期91卷 136-137页

作者： LIU Yongjie LI Yongxiang LI Hong NIU Yuanzhe LIU Fan DONG yangkun Northwest University Xi’anShaanxi 710069

1 Introduction Some Cyprinidae fossils have been reported about 42.km east of the fossil site in the same period of Wulan Husentu1 layer,and have been used as an important fossil evidence for a deep understanding of the

关键词： The new discovery of Oligocene cyprinidae fossil in Qaidam basin Northwest China length

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茂兰保护区华南五针松群落乔木层主要物种的种间亲和性

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内蒙古林业调查设计 2024年第1期47卷 87-91+44页

作者：柳华富智扬坤姚芊陈正仁王登鸿贵州茂兰国家级自然保护区管理局贵州华旭林业勘察设计有限公司

基于茂兰保护区华南五针松群落调查数据，采用重要值、物种联结指数、Spearman秩相关系数、生态位宽度和生态位重叠等指标，探明了15个主要树种的种间联结性、相互关系及生态位。结果表明：(1)群落总体呈不显著正联结，物种间的相互作... 详细信息

基于茂兰保护区华南五针松群落调查数据，采用重要值、物种联结指数、Spearman秩相关系数、生态位宽度和生态位重叠等指标，探明了15个主要树种的种间联结性、相互关系及生态位。结果表明：(1)群落总体呈不显著正联结，物种间的相互作用竞争不强烈，形成的种间搭配关系对资源的利用较好；(2.主要物种重要值和生态位宽度值排前5的分别为：华南五针松、化香、乌冈栎、荔波鹅耳枥和青冈栎，在群落中个体数量较多，具有相似的生态习性和资源需求，既是乔木层的优势种和重要种，也是群落演替的主导树种，优势种间具有较高的生态位重叠，存在着激烈的竞争；(3)Spearman秩相关系数显示的105种对中，显示正相关的有66对，负相关有39对，比值为1.692.种间相关性较为松散，各种群趋向于独立分布，有较大的随机性。

关键词：华南五针松总体联结种间相关性生态位群落

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Sprayed PAA-CaO_(2.nanoparticles combined with calcium ions and reactive oxygen species for antibacterial and wound healing

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Regenerative Biomaterials 2023年第1期10卷 1356-1371页

作者： Hong Yu Jiale Sun Kepeng She Mingqi Lv Yiqiao Zhang Yawen Xiao yangkun Liu Changhao Han Xinyue Xu Shuqing Yang Guixue Wang Guangchao Zang Tissue and Cell Biology Lab Teaching&Management CenterChongqing Medical UniversityChongqing 400016China Chongqing University Central Hospital Chongqing Emergency Medical CenterChongqing 400030China Key Laboratory for Biorheological Science and Technology of Ministry of Education State and Local Joint Engineering Laboratory for Vascular ImplantsBioengineering College of Chongqing UniversityChongqing 400030China Jinfeng Laboratory Chongqing 401329China

The most common socioeconomic healthcare issues in clinical are burns,surgical incisions and other skin *** lesion healing can be achieved with nanomedicines and other drug application *** study developed a nano-spray based on cross-linked amorphous calcium peroxide(CaO_(2.)nanoparticles of polyacrylic acid(PAA)for treating skin wounds(PAA-CaO_(2.nanoparticles).CaO_(2.serves as a‘drug’precursor,steadily and continuously releasing calcium ions(Ca^(2.))and hydrogen peroxide(H_(2.O_(2.)under mildly acidic conditions,while PAA-CaO_(2.nanoparticles exhibited good spray behavior in aqueous *** demonstrated that PAA-CaO_(2.nanoparticles exhibited low cytotoxicity and allowed L92. cells proliferation and migration in *** effectiveness of PAA-CaO_(2.nanoparticles in promoting wound healing and inhibiting bacterial growth in vivo was assessed in SD rats using full-thickness skin defect and Staphylococcus aureus(***)-infected wound models based *** results revealed that PAA-CaO_(2.nanoparticles demonstrated significant advantages in both ***,the infected rats’skin defects healed in 12.*** benefits are linked to the functional role of Ca^(2.)coalesces with H_(2.O_(2.as known antibacterial and healing-promoted ***,we developed nanoscale PAA-CaO_(2.sprays to prevent bacterial development and heal skin lesions.

关键词： polyacrylic acid calcium peroxide nanomedicines antibacterial wound healing

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Risk Evaluation on Logistics Finance of Agricultural Products Based on Fuzzy-AHP Model

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Asian Agricultural Research 2015年第9期7卷 1-5 8,8页

作者： Yan PANG yangkun XIA School of Transportation and Logistics Central South University of Forestry and Technology

The development of logistics finance business for agricultural products is the best way to realize the common interests of logistics enterprises,small and medium-sized agricultural product enterprises and financial institutions,which will contribute to the development of China's new socialist rural economy and the construction of " two-oriented society". As the agricultural products have some special attributes,it's easy to create the risk in carrying out the logistics finance business. The paper constructs a risk evaluation indicator system for logistics finance of agricultural product,and uses the Fuzzy-AHP model to evaluate. The results show that the comprehensive risk level is normal risk,which shows that third-party logistics enterprises can carry out the logistics financial business of agricultural products,but the risks from logistics enterprises and agricultural collateral need to be prevented.

关键词： Logistics finance Agricultural products Risk evalu

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