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考虑结合面接触刚度的机床床身动态特性分析

振动与冲击 2024年第8期43卷 310-318页

作者：刘书晟史军孙建宏秦文强曾艳泓张松山东大学高效洁净机械制造教育部重点实验室济南250061 济南二机床集团有限公司济南250022 重庆机床(集团)有限责任公司重庆401336

床身结合面刚度是影响机床动态特性,进而影响机床加工精度的重要因素之一。为了获得精确的机床动态特性参数,运用接触刚度预测模型识别出了床身结合面的接触刚度并建立了等效动力学模型。首先,建立接触刚度预测模型;其次,通过预测模型... 详细信息

床身结合面刚度是影响机床动态特性,进而影响机床加工精度的重要因素之一。为了获得精确的机床动态特性参数,运用接触刚度预测模型识别出了床身结合面的接触刚度并建立了等效动力学模型。首先,建立接触刚度预测模型;其次,通过预测模型识别出两种材料(铸铁和矿物复合材料)床身结合面的接触刚度;然后,利用结合面接触特性参数,基于弹簧单元约束建立有限元模型;最后,对比有限元模态频率和试验模态频率,发现基于弹簧单元约束的有限元模态频率与试验模态频率一致性较好,且该模型对铸铁和矿物复合材料均有效。研究表明考虑结合面接触刚度的机床床身有限元模型更具合理性,可以为分析机床动力学特性和优化机床结构提供理论依据。

关键词：结合面接触刚度动态特性模态试验

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基于多路光流信息的微光视频增强算法

现代电子技术 2024年第16期47卷 13-22页

作者：刘书生王九杭童官军中国科学院大学北京100049 中国科学院上海微系统与信息技术研究所上海201800

图像和视频是记录真实场景信息的重要媒介,它们包含丰富而详细的视觉内容,可以开发各种智能系统来执行各种任务。特别是对于低照度条件下的视频,提升其清晰度和细节可以更好地表现和还原真实场景。针对在夜间低照度环境条件下对周围环... 详细信息

图像和视频是记录真实场景信息的重要媒介,它们包含丰富而详细的视觉内容,可以开发各种智能系统来执行各种任务。特别是对于低照度条件下的视频,提升其清晰度和细节可以更好地表现和还原真实场景。针对在夜间低照度环境条件下对周围环境感知的需求,提出一种基于多路光流信息时间一致性的微光视频增强算法。通过引入预测的光流与真实的光流信息,构建三分支孪生网络对微光视频进行增强;同时针对微光视频存在的低信噪比以及模糊化问题,设计一种基于双尺度注意力机制的微光视频去噪模块(CA-Swin模块),以提升网络的去噪性能。通过在DAVIS数据集上进行对比实验和评估,得出所提网络在增强微光视频方面更高效,鲁棒性显著;且该策略还具有通用性,可以直接扩展到大规模数据集。

关键词：微光视频增强光流信息时间一致性三分支孪生网络双尺度注意力机制微光视频去噪模块视频帧

Differences in mating behavior lead to asymmetric mating interactions and consequential changes in sex ratio between an invasive and an indigenous whitefly

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Integrative Zoology 2012年第1期7卷 1-15页

作者： Junbo LUAN shusheng liu Ministry of Agriculture Key Laboratory of Agricultural Entomology Institute of Insect SciencesZhejiang UniversityHangzhouChina

The invasive B whitefly and the indigenous ZHJ2 whitefly in China of the Bemisia tabaci complex represent two previously allopatric cryptic *** experiments have shown that the invasive B can displace the indigenous ***,we observed the mating behavior and mating interactions between B and ZHJ2 to elucidate the behavioral mechanisms underlying their *** 2 species are able to mate with each oth-er,although at a significantly lower frequency than that between males and females within the same ***-mated females produce only male progeny,indicating reproductive *** mating had only a marginal effect on reproduction of females in either *** observations on mating interactions between the 2 species showed that B had higher sexual activity than ZHJ2.B males were more like-ly to interrupt courtships initiated by rival males than ZHJ2 *** with ZHJ2 males,B males were also more likely to successfully interrupt courtships initiated by rival heterospecific males than by males of the same *** addition,B males guarded B females post-copulation,whereas ZHJ2 males did *** the 2 species co-occurred,the behavioral differences and interactions between them resulted in an increased propor-tion of females produced in the offspring of B but reduced proportion of females in the progeny of *** asymmetric mating interactions might be an important mechanism underlying the displacement of ZHJ2 by *** study shows that reproductive interference might contribute to the competitive exclusion between closely related species during biological invasions.

关键词： Bemisia tabaci biological invasion courtship displacement mating interactions

New insights into the transovarial transmission of the symbiont Rickettsia in whiteflies

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Science China(Life Sciences) 2021年第7期64卷 1174-1186页

作者： Hongwei Shan Yinquan liu Junbo Luan shusheng liu Ministry ofAgriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects Institute ofInsect SciencesZhejiang UniversityHangzhou 310058China College of Plant Protection Shenyang Agricultural UniversityShenyang 110866China

Endosymbiont transmission via eggs to future host generations has been recognized as the main strategy for its persistence in insect hosts;however,the mechanisms for transmission have yet to be ***,we describe the dynamic locations of Rickettsia in the ovarioles and eggs during oogenesis and embryogenesis in a globally significant pest whitefly Bemisia *** populations of the whitefly have a high prevalence of Rickettsia,and in all Rickettsia-infected individuals,the bacterium distributes in the body cavity of the host,especially in the midgut,fat body,hemocytes,hemolymph,and near *** distribution of Rickettsia was subjected to dynamic changes in the ovary during oogenesis,and our ultrastructural observations indicated that the bacteria infect host ovarioles during early developmental stages via two routes:(i)invasion of the tropharium by endocytosis and then transmission into vitellarium via nutritive cord and(ii)entry into vitellarium by hijacking bacteriocyte *** of the Rickettsia are degraded in the oocyte cytoplasm in late-stage ***,a few reside beneath the vitelline envelope of mature eggs,spread into the embryo,and proliferate during embryogenesis to sustain high-fidelity transmission to the next *** findings provide novel insights into the maternal transmission underpinning the persistence and spread of insect symbionts.

关键词： Bemisia tabaci Rickettsia symbiosis vertical transmission

Phase Portraits and Flow Regimes in a Circular Couette System with Counter-Rotating Cylinders

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Chinese Physics Letters 1991年第1期8卷 9-12页

作者： liu shusheng SHA Ernan YAO Lan WANG Mingtan Department of Physics Tianjin UniversityTianjin 300072 Institute of Theoretical Physics Academia SinicaBeijing 100080

Experiments have been conducted on the circular Couette system,established recently in our *** using ***-electronic modulation feedback Laser Doppler Velocimetry technique,the velocity time series data with higher signal-noise ratio,power spectra,phase portraits and Poincare sections were *** scenarios to chaos were *** is the Ruelle-Takens scenario,while the other(when both cylinders of the Couette system are counter-rotating)is quite different from it,A tremendous variety of flow regimes and a new state were observed.A tentative explanation is made for the new state.

关键词： state Couette system

Spatial Distribution Prediction of Laterite Bauxite in Bolaven Plateau Using GIS

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Journal of Earth Science 2019年第5期30卷 1010-1019页

作者： Yuan Ouyang Hanhu liu Xiao Wang shusheng liu Jinghua Zhang Hui Gao Chengdu Center China Geological Survey Chengdu 610081 China Key Laboratory of Geoscience Spatial Information Technology Ministry of Land and Resources Chengdu University of Technology Chengdu 610059 China

Mineral resources are the most important natural resources for developing countries. Bauxite is an indispensable mineral resource for industrial production. Potential assessment of bauxite is an important issue in Indochina Peninsula. In this paper, the factors affecting the mineralization of the lateritic bauxite are analyzed. The collected spatial data are processed and the information is extracted to obtain the spatial extent of favorable constraints. Then, the spatial distribution of potential bauxites on the Bolaven Plateau has been investigated with a Boolean modeling process in GIS environment on the basis of some constraints such as rock, elevation, topographical features and vegetation coverage. Finally, based on the hydrogeological conditions and alteration information of Fe3+ and OH-, the bauxite mapping has been carried out. There are twenty bauxite metallogenic areas delineated, with a total area of 750 km2, which is 5% of the entire study area. This has greatly reduced the scope of the field investigation. Seven of the twenty predicted areas were validated in the field and six of them were found to have bauxite mineralization. Using the methods proposed in this study, the potential bauxite for the entire Bolaven Plateau could be achieved much more cheaply than the traditional methods. This study also provides a good idea for the prediction of laterite bauxite in the other regions of the Indochina Peninsula.

关键词： Bolaven Plateau GIS laterite bauxite Boolean model geochemistry remote sensing

New Re-Os Dating of Auriferous Pyrite from the Suoluogou Large Gold Deposit in Muli County, West Sichuan Province

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Acta Geologica Sinica(English Edition) 2018年第3期92卷 1270-1271页

作者： NIE Fei liu shusheng SHI Meifeng SHI Hongzhao FAN Wenyu Chengdu Center China Geological Survey Chengdu 610081 Sichuan China

Objective The Suoluogou gold depositin Muli County of Sichuan Province is located in the southern section of the GanziLitang suture zone(***),which is the largest gold deposit discovered in this suture zone in recent *** present,the exploration of the Suoluogou gold deposit is still in progress,and the amount of resource is increasing.

关键词： the Suoluogou Large Gold Deposit West Sichuan Province

Geological Features,Mineralization Types and Metallogenic Setting of the Phlaythong Large Iron Deposit,Southern Laos

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Acta Geologica Sinica(English Edition) 2015年第4期89卷 1423-1424页

作者： liu shusheng FAN Wenyu LUO Maojin YANG Yongfei College of Earth Sciences Chengdu University of Technology Chengdu Center China Geological Survey

The Phlaythong large iron deposit in Shampasak of southern Laos,is located in the Kon Tum microblock （Fig.1A）,central-southern part of the Indo-China block,and the geographic coordinate of the central mining area is... 详细信息

关键词： Geological Features,Mineralization Types and Metallogenic Setting of the Phlaythong Large Iron Deposit,Southern Laos TFe

Biclique cryptanalysis using balanced complete bipartite subgraphs

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Science China(Information Sciences) 2016年第4期59卷 208-210页

作者： Zheng GONG shusheng liu Yamin WEN Yiyuan LUO Weidong QIU School of Computer Science South China Normal University State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of Sciences School of Mathematics and Statistics Guangdong University of Finance and Economics School of Electronics and Information Shanghai Dian Ji University School of Information Security Engineering Shanghai Jiao Tong University

Dear editor,At Asiacrypt 2011,Bogdanov et al.[1]formally defined the biclique cryptanalysis method and proposed the first key recovery attack on full-round AES faster than exhaustible search in single-key *** basic idea underlying the biclique cryptanalysis is to determine two independent(or interleaving)differential paths in the forward and the backward direction to construct a biclique for a

关键词： BCBS Biclique cryptanalysis using balanced complete bipartite subgraphs MITM