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基于声全息法和单目视觉技术的柴油机噪声可视化实现

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机械设计与制造 2024年第8期402卷 276-281页

作者：毕玉华梁加宝姚国仲吴彪昆明理工大学云南省内燃机重点实验室云南昆明650500

柴油机属于多噪声耦合动力装置,其噪声的识别和控制是内燃机研究领域的难点。为实现柴油机噪声的可视化,本研究结合了近场声全息法与单目视觉技术,开发了基于Labview的声像匹配模块,测试系统人机界面友好,并通过已知声源试验验证了声像... 详细信息

柴油机属于多噪声耦合动力装置,其噪声的识别和控制是内燃机研究领域的难点。为实现柴油机噪声的可视化,本研究结合了近场声全息法与单目视觉技术,开发了基于Labview的声像匹配模块,测试系统人机界面友好,并通过已知声源试验验证了声像匹配模块的正确性。将验证后的测试系统应用于高压共轨柴油机对主/次推力侧声源进行识别,结果表明:在大气压力为80kPa、转速为1800r/min的最大扭矩工况下,主推力侧出现较大辐射噪声的位置为中冷器进气管、曲轴定时齿形带轮、排气管、脚架和涡轮增压器等;次推力侧辐射噪声峰值出现在起动机位置。

关键词：近场声全息单目视觉系统声像匹配柴油机

Investigation of the sediment transport capacity in vegetated open channel flow

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Journal of Hydrodynamics 2021年第2期33卷 386-389页

作者： Wen-xin huai Xiang Wang Yakun Guo Zhao-hua Sun {2.-hua Yang state key {2. of Water Resources and Hydropower Engineering science Wuhan UniversityWuhan 430072China Faculty of Engineering and Informatics University of BradfordBradfordUK

The suspended sediment transport capacity is important for estimating the suspended load concentration and the ecological environment of the *** far,few studies have been conducted to investigate the suspended sediment transport capacity in the vegetated sediment-laden *** this study,a new formula is derived to predict the sediment transport capacity in a vegetated flow by considering the absolute value of the energy loss between the sediment-laden flow and the clear water ***,the formula is expressed in a practical form by using the logarithmic matching method.

关键词： Sediment transport vegetation suspended sediment concentration

A NOVEL DESIGN OF BEHAVIORAL ANALYSIS CAPABILITY IN MOBILE SNS

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A NOVEL DESIGN OF BEHAVIORAL ANALYSIS CAPABILITY IN MOBILE S...

Incipient sediment motion in vegetated open-channel flows predicted by critical flow velocity

2.09 IEEE International Conference on Communication technology and Applications（ICCTA2.09）

作者： Guangxi Cheng~1 Zhihan Liu~1 hua Zou~1 Hao Dong~2.1 state {2. laboratory of Networking and Switching Beijing university of Posts and Telecommunications Beijing 2.ystem Architecture Department Communication Services R&D Institute zhong Xing Telecommunication Equipment Company Limited

＜正＞This paper introduces a novel design of the Behavioral Analysis Capability in Mobile SNS. The capability has a basic part comprises relationship based interface,content based interface and time based *** basic capability can either provide APIs directly up to applications or encapsulate into advanced capability with the core of relationship based ***,explaining the usability of this capability through its disposition in Mobile ***,by using basic and advanced interfaces respectively,two typical application examples represent the practicability of Behavioral Analysis Capability.

关键词： Behavioral analysis capability Mobile SNS

来源： cnki会议评论

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Journal of Hydrodynamics 2022年第1期34卷 63-68页

作者： Xiang Wang Shuolin Li zhong-hua Yang Wen-xin huai state key {2. of Water Resources and Hydropower Engineering science Wuhan UniversityWuhan430072China Department of Civil and Environmental Engineering Duke UniversityDurhamNCUSA Nicholas School of the Environment and Earth science Duke UniversityDurhamNCUSA

Incipient sediment motion plays a key role in scouring and bed load transport. However, the incipient sediment motion in the vegetated open-channel flows has yet to be fully understood. This study aims to quantify the critical conditions of the sediment particle movement in the presence of emergent and submerged vegetation. A new formula of the critical flow velocity was proposed to predict the incipient sediment motion based on the force balance equation of a sediment particle and the assumption that the velocity distribution in the bed roughness boundary layer fits the logarithmic law. Analysis of the derived formula revealed that the critical flow velocity for incipient sediment motion decreases with the increase in vegetation density. The proposed formula agrees well with the experimental data in the literature, thereby implying that the critical flow velocity can effectively quantify the incipient sediment motion in the vegetated open channel flows.

关键词： Incipient sediment motion critical flow velocity vegetation

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基于光纤技术的叶端定时传感器

天津大学学报（自然科学与工程技术版） 2002年第5期35卷 606-610页

作者：王宇华叶声华段发阶冯心海郑义忠天津大学精密仪器与光电子工程学院精密测试技术及仪器国家重点实险室天津300072 佛山科学技术学院工学院佛山528000

叶端定时测量是一种新型的在线实时测量叶片振动的有效方法 ,激光光纤叶端定时传感器是整个测试系统设计的关键 .该文研究了叶端定时测量方法 ,并对应用于高速旋转汽轮机叶片振动在线实时监测的光纤叶端定时传感器进行了设计研究和试验 ... 详细信息

叶端定时测量是一种新型的在线实时测量叶片振动的有效方法 ,激光光纤叶端定时传感器是整个测试系统设计的关键 .该文研究了叶端定时测量方法 ,并对应用于高速旋转汽轮机叶片振动在线实时监测的光纤叶端定时传感器进行了设计研究和试验 ,研究了一个具有高分辨、大频宽和高信噪比的激光光纤传感器的设计方案。

关键词：光纤叶片振动高速旋转叶端定时传感器叶端定时测量法激光光纤传感器

CURVED OPEN CHANNEL FLOW ON VEGETATION ROUGHENED INNER BANK

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Journal of Hydrodynamics 2012年第1期24卷 124-129页

作者： huaI Wen-xin LI Cheng-guang ZENG Yu-hong QIAN zhong-dong YANG zhong-hua state key {2. of Water Resources and Hydropower Engineering science Wuhan UniversityWuhan 430072China

A RNG numerical model together with a laboratory measurement with Micro ADV are adopted to investigate the flow through a 180o curved open channel（a 4 m straight inflow section,a 180o curved section,and a 4m straight outflow section）partially covered with rigid vegetations on its inner *** the combined action of the vegetation and the bend flow,the flow structure is *** stream-wise velocities in the vegetation region are much smaller than those in the non-vegetation region due to the retardation caused by the *** the same reason,no clear circulation is found in the vegetated region,while in the non-vegetation region,a slight counter-rotating circulation is found near the outer bank at both 90o and downstream curved cross-sections.A comparison between the numerical prediction and the laboratory measurement shows that the RNG model can well predict the flow structure of the bend flow with ***,the shear stress is analyzed based on the numerical *** much smaller value in the inner vegetated region indicates that the vegetation can effectively protect the river bank from scouring and erosion,in other words,the sediment is more likely to be deposited in the vegetation region.

关键词： RNG numerical model non-submerged rigid vegetation bend flow stream-wise velocities shear stress

Bi_(2.S_(3) Nanostructures: A New Photocatalyst

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Nano Research 2010年第5期3卷 379-386页

作者： Tong Wu Xinggui Zhou hua Zhang Xinhua {2. state key {2. of Chemical Engineering Department of ChemistryEast China University of Science and TechnologyShanghai 200237China

Uniform colloidal Bi_(2.S_(3) nanodots and nanorods with different sizes have been prepared in a controllable manner via a hot injection method. X-ray diffraction (XRD) results show that the resulting nanocrystals have an orthorhombic structure. Both the diameter and length of the nanorods increase with increasing concentration of the precursors. All of the prepared Bi_(2.S_(3) nanostructures show high efficiency in the photodegradation of rhodamine B, especially in the case of small sized nanodots-which is possibly due to their high surface area. The dynamics of the photocatalysis is also discussed.

关键词： Bi_(2.S_(3) nanostructures hot injection photocatalyst

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毕赤酵母发酵生产中的水蛭素降解顺序

微生物学通报 2004年第5期31卷 24-27页

作者：杨继忠周祥山解锡军尤金花张元兴解福生华东理工大学生物反应器工程国家重点实验室上海200237 山东东阿阿胶股份有限公司聊城252201

水蛭素 (rHV2. Lys4 7)是一个具有 65个氨基酸的抗凝活性肽。在毕赤酵母高密度发酵分泌表达过程中 ,发酵上清中可检出 4个水蛭素活性组份 ,分别为Hir65及其C 末端切除 1～ 3个氨基酸的Hir64、Hir63和Hir62.但目前 4种组份间的衍生关系... 详细信息

水蛭素 (rHV2. Lys4 7)是一个具有 65个氨基酸的抗凝活性肽。在毕赤酵母高密度发酵分泌表达过程中 ,发酵上清中可检出 4个水蛭素活性组份 ,分别为Hir65及其C 末端切除 1～ 3个氨基酸的Hir64、Hir63和Hir62.但目前 4种组份间的衍生关系还不清楚 ,以从发酵上清液中纯化分离所得的 4个组份作为底物 ,加入到菌体裂解液中 ,发现Hir64、Hir63和Hir62.份是由羧肽酶依次降解Hir65肽链C 末端 1个氨基酸后的产物。

关键词：毕赤酵母水蛭素降解裂解液

Longitudinal dispersive coefficient in channels with aquatic vegetation:A review

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水动力学研究与进展B辑:英文版 2023年第3期35卷 379-395页

作者： Liu Yang Hao-ze Fang zhong-hua Yang Wen-xin huai state key {2. of Water Resources Engineering and Management Wuhan University Wuhan 430072 China

The determination of longitudinal dispersion coefficient in rivers is necessary for pollution control,environmental risk assessment,and *** rivers with aquatic vegetation,the flow field is remarkably modified by canopies,which affects velocity profiles and dispersion characteristics dominated by the heterogeneity of the velocity *** dispersion is deduced from lateral and vertical longitudinal velocity gradients for compound channels with vegetated floodplains and rectangular channels with river-wide vegetation,*** many efforts have been exerted to clarify the dispersion process in different conditions and predict the diffusion of contaminants in vegetated rivers,no studies have introduced it *** study reviews the dispersion coefficient characteristics,including magnitude,main impacted factors,and relationships with flow and vegetation features,in channels with aquatic canopies considering the variation of impact factors changing with the different vegetation and river morphology *** typical methodologies for determining longitudinal dispersion coefficients are also summarized to understand the dispersion processes and *** from the pioneer outcomes of previous studies,the review also emphasizes the deficiency of existing studies and suggests possible future directions for improving the theory of dispersion in vegetated channels.

关键词： Vegetated flows longitudinal dispersion coefficient spatial heterogeneity