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星敏感器随机振动抑制方法设计与验证

哈尔滨工程大学学报 2024年第9期45卷 1744-1749页

作者：王宏旭郭金生张冀鹞哈尔滨工业大学航天学院黑龙江哈尔滨150080

针对商业小卫星星敏支架轻量化和小型化约束下常见的随机振动响应过大的问题,本文提出一种抑制随机振动响应的隔振器设计方法。根据某型号卫星的构型、布局设计和星敏局部安装方式,采用有限元方法对振动响应进行分析,分析认为无隔振设... 详细信息

针对商业小卫星星敏支架轻量化和小型化约束下常见的随机振动响应过大的问题,本文提出一种抑制随机振动响应的隔振器设计方法。根据某型号卫星的构型、布局设计和星敏局部安装方式,采用有限元方法对振动响应进行分析,分析认为无隔振设计时的星敏局部随机振动响应过大。根据随机振动响应的幅频特性,结合卫星安装空间与安装接口,提出一种基于橡胶隔振器的振动抑制方法,并通过幅频法分析其有效性。整星振动试验表明:隔振器能够抑制约80%的随机振动响应均方根值,并且正弦振动放大后的量级仍能满足星敏感器力学要求,振动前后的星敏感器最大指向偏差约为0.02167°。目前该型号卫星已成功在轨应用,星敏感器在轨工作正常,验证了本文提出的基于橡胶隔振器的振动抑制方法的有效性,能够为其他型号航天器的工程实践提供技术参考。

关键词：商业小卫星星敏感器振动抑制隔振器结构分析有限元模拟振动试验动力学

维普期刊数据库博看期刊

基于稀疏重构注意力机制的绝缘子缺陷检测方法

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广东电力 2024年第5期37卷 104-111页

作者：刘敏周国亮王红旭郑怿国网冀北电力有限公司北京100053 国网冀北电力有限公司技能培训中心河北保定071051

针对当前输电线路绝缘子缺陷样本数量少、缺陷目标背景复杂干扰导致检测过程中出现的特征冗余以及检测精度低等问题,提出基于稀疏重构注意力(sparse reconstruction dual attention,SRDA)机制的目标检测模型。首先,为了降低深层特征冗... 详细信息

针对当前输电线路绝缘子缺陷样本数量少、缺陷目标背景复杂干扰导致检测过程中出现的特征冗余以及检测精度低等问题,提出基于稀疏重构注意力(sparse reconstruction dual attention,SRDA)机制的目标检测模型。首先,为了降低深层特征冗余对模型的影响,采用稀疏重构机制对模型的深层特征层进行筛选和过滤;其次,为了增强模型对不同背景下目标区域的表达能力,提出位置注意力机制来捕获浅层特征目标区域的上下文信息,并引入通道注意力机制在深层特征层上加强对特定类别语义的特征表示,增强缺陷目标的语义信息;最后,通过对无人机拍摄采集的输电线路绝缘子图像进行缺陷检测实验,证明该模型能够获取精确的缺陷特征,提高绝缘子缺陷检测精度,与其他模型相比,该模型具有一定的优越性。

关键词：稀疏重构绝缘子缺陷检测注意力机制语义信息

维普期刊数据库博看期刊

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医药学实验室潜在的生物安全风险与防范措施

中国比较医学杂志 2024年第4期34卷 109-113页

作者：陈沫陶佳颐王宏旭张庆建中国医学科学院药物研究所条件设备处北京100050

医药学研究实验室涉及的研究领域十分宽泛,实验中应用的多种材料包括动物、微生物及纳米颗粒物等,所产生的废弃物也日益增多,存在着一定的生物安全隐患。本文概述了基因扩增、基因重组、病原微生物研究、纳米研究、动物实验、基因编辑... 详细信息

医药学研究实验室涉及的研究领域十分宽泛,实验中应用的多种材料包括动物、微生物及纳米颗粒物等,所产生的废弃物也日益增多,存在着一定的生物安全隐患。本文概述了基因扩增、基因重组、病原微生物研究、纳米研究、动物实验、基因编辑动物及实验废弃物等的潜在安全风险,提出了从制定严格的规章管理制度和完善硬件设施、加强教育培训、增强安全防范意识为主导的实验室生物安全风险防范措施。

关键词：医药学研究实验室生物安全安全管理

NUMERICAL SIMULATION FOR SHAPE OF COLD ROLLING ALUMINUM STRIP ON 4-HIGH MILL WITH ROLL SHIFTED

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中国有色金属学会会刊：英文版 1998年第3期8卷 30-36页

作者： hongxu, wang Jianjun, Liu Jiachuang, Lian Junbo, Liu Yanshan Univ Qinhuangdao China

１ＩＮＴＲＯＤＵＣＴＩＯＮＡｓｔｈｅｍｉｌｗｉｔｈｒｏｌｓｈｉｆｔｅｄｈａｓｇｏｏｄｓｈａｐｅｃｏｎｔｒｏｌｃｈａｒａｃｔｅｒｉｓｔｉｃ，ｉｔｈａｓｂｅｅｎａｐｐｌｉｅｄｔｏｐｒｏｄｕｃｔｉｏｎｏｆｃｏｌｄｒｏｌ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＡｓｔｈｅｍｉｌｗｉｔｈｒｏｌｓｈｉｆｔｅｄｈａｓｇｏｏｄｓｈａｐｅｃｏｎｔｒｏｌｃｈａｒａｃｔｅｒｉｓｔｉｃ，ｉｔｈａｓｂｅｅｎａｐｐｌｉｅｄｔｏｐｒｏｄｕｃｔｉｏｎｏｆｃｏｌｄｒｏｌｅｄａｎｄｈｏｔｒｏｌｅｄｓｔｒｉ...

关键词： mill with roll shifted least square and collocation method variation method shape

Determination of Optimal Work Roll Profile for Cold Strip Mill

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Journal of Iron and Steel Research International 1998年第1期5卷 8-12页

作者： wang hongxu Lian Jiachuang Liu Hongmin Yanshan University

The model of predicting distribution of strip thickness at the exit and tension stress is established by using weighted residual method and variational method with consideration of rolled metal lateral flow.A New method of calculating loaded roll gap in relation to target tension stress is *** minimum square summation of loaded roll gap deviation is used as an objective function for the first time to optimize initial work roll profile.

关键词： work roll profile cold rolling optimization weighted residual method variational method strip

BPGM: A Big Graph Mining Tool

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Tsinghua Science and Technology 2014年第1期19卷 33-38页

作者： Yang Liu Bin Wu hongxu wang Pengjiang Ma School of Computer Science Beijing University of Posts and Telecommunications

The design and implementation of a scalable parallel mining system target for big graph analysis has proven to be challenging. In this study, we propose a parallel data mining system for analyzing big graph data generated on a Bulk Synchronous Parallel （BSP） computing model named BSP-based Parallel Graph Mining （BPGM）. This system has four sets of parallel graph mining algorithms programmed in the BSP parallel model and a well-designed workflow engine optimized for cloud computing to invoke these algorithms. Experimental results show that the graph mining algorithm components in BPGM are efficient and have better performance than big cloud-based parallel data miner and BC-BSP.

关键词： cloud computing parallel algorithms graph data analysis data mining social network analysis

脂肪酸代谢对骨质疏松骨骼细胞的影响及中西医干预研究

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中国骨质疏松杂志 2024年第2期30卷 228-233页

作者：曹奇孙广江戚晓楠智猛那俊夫王洪旭姚啸生辽宁中医药大学辽宁沈阳110847 辽宁中医药大学附属医院辽宁沈阳110000

脂肪酸代谢包括脂肪酸的合成、吸收、氧化和衍生,在细胞和器官水平上发挥着重要的作用。近年来的研究发现,骨质疏松模型的骨骼细胞中发生了脂肪酸代谢的特征性改变,提示脂肪酸代谢异常可能为骨质疏松症的发病机制之一。因此本文重点探... 详细信息

脂肪酸代谢包括脂肪酸的合成、吸收、氧化和衍生,在细胞和器官水平上发挥着重要的作用。近年来的研究发现,骨质疏松模型的骨骼细胞中发生了脂肪酸代谢的特征性改变,提示脂肪酸代谢异常可能为骨质疏松症的发病机制之一。因此本文重点探讨脂肪酸代谢途径在调节骨质疏松症中成骨细胞、破骨细胞等特定细胞的功能及相关的病理细胞反应中的作用,并总结基于脂肪酸代谢途径的骨质疏松潜在治疗药物,为骨质疏松症的治疗提供科学依据。

关键词：骨质疏松症脂肪酸成骨细胞破骨细胞

Numerical modeling of contaminant advection impact on hydrodynamic diffusion in a deformable medium

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第3期14卷 994-1004页

作者： Chunguang wang Shuqing Liu Xingkai Shi Guanglei Cui hongxu wang Xing Jin Kunkun Fan Songtao Hu College of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao266590China Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang110004China Shandong Provincial Geo-Mineral Engineering Co. Ltd.Jinan250013China

The self-weight of solid waste or machine-rolled compaction can induce or trigger contaminant migration in the *** the consolidation-induced hydraulic gradient driving solution transport has been extensively investigated,little attention has been paid to ion migration caused by its concentration gradient *** is necessary to more precisely predict the multi-stage contaminant transports in deforming porous *** on the modified Cam-clay model,the proposed fluid-solid coupled model can simulate the elastoplastic deformation behavior of layered kaolinite and KBr solution transport/sorption,and its modeling results were validated by published laboratory *** solid-fluid interactions were analyzed by comparing various transport manners of K^(+)and Br^(−)from excess pore pressure generation to *** reveal that the consolidation process can accelerate KBr solute advection from the contaminated layer into the uncontaminated layer,and then affects the subsequent diffusion,mechanical dispersion and sorption for K^(+)and Br^(−).The simulations also indicate that consolidation-induced solute transport is time-dependent,and therefore the ion diffusion and mechanical dispersion should receive more attention.

关键词： Consolidation Advection Diffusion Sorption

Revaluating coal permeability-gas pressure relation under various gas pressure differential conditions

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International Journal of Coal Science & Technology 2023年第4期10卷 203-216页

作者： Chunguang wang hongxu wang Derek Elsworth Guanglei Cui Bingqian Li Meng Zhou Wenxin Li Jiyuan Zhang College of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao 266590China Energy and Mineral Engineering GeosciencesG3 Centerand EMS Energy InstitutePennsylvania State UniversityUniversity ParkPAUSA Key Laboratory of Ministry of Education On Safe Mining of Deep Metal Mines Northeastern UniversityShenyang 110004China Pingdingshan Tianan Coal Mining Co. LTDPingdingshanHenan 467003China School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China

Identifying changes in coal permeability with gas pressure and accurately codifying mean efective stresses in laboratory samples are crucial in predicting gas-fow behavior in coal reservoirs. Traditionally, coal permeability to gas is assessed using the steady-state method, where the equivalent gas pressure in the coal is indexed to the average of upstream and downstream pressures of the coal, while ignoring the nonlinear gas pressure gradient along the gas fow path. For the fow of a compressible gas, the traditional method consistently underestimates the length/volume-averaged pressure and overestimates mean efective stress. The higher the pressure diferential within the sample, the greater the error between the true mean pressure for a compressible fuid and that assumed as the average between upstream and downstream pressures under typical reservoir conditions. A correction coefcient for the compressible fuid pressure asymptotes to approximately 1.3%, representing that the error in mean pressure and efective stress can be on the order of approximately 30%, particularly for highly pressure-sensitive permeabilities and compressibilities, further amplifying errors in evaluated reservoir properties. We utilized this volume-averaged pressure and efective stress to correct permeability and compressibility data reported in the literature. Both the corrected initial permeability and the corrected pore compressibility were found to be smaller than the uncorrected values, due to the underestimation of the true mean fuid pressure, resulting in an overestimation of reservoir permeability if not corrected. The correction coefcient for the initial permeability ranges from 0.6 to 0.1 (reservoir values are only approximately 40% to 90% of laboratory values), while the correction coefcient for pore compressibility remains at approximately 0.75 (reservoir values are only approximately 25% of laboratory value). Errors between the uncorrected and corrected parameters are quantifed un

关键词： Gas compressibility Coal permeability Pressure diferential Mean gas pressure