检索结果-南通市图书馆

Influence of Center of Gravity Location on Flight Dynamic Stability in a Hovering Tailless FW-MAV: lateral Motion

Journal of Bionic Engineering 2020年第1期17卷 148-160页

作者： Loan Thi Kim Au Hoon Cheol Park Department of Smart Vehicle Engineering and Artificial Muscle Research Center Konkuk UniversitySeoul 05029Korea

This paper reports the effect of the Center of Gravity(CG)position on lateral flight dynamic stability of hovering KUBeetle,a tailless FW-MAV,providing further insights on the effects of asymmetries in body mass distribution and wing kinematics.For the current study,the standard linearized equations of motion were applied as in the previous work on longitudinal dynamic stability.The stability derivatives were acquired using the computational fluid dynamic methods via the commercial software of ANSYS Fluent.There exists a stable region for CG between 2.6%and 3.5%of the mean chord below the wing pivot point,in which the lateral motion of hovering KUBeetle is passively stable.For CG below the stable region,because of an unstable oscillatory mode,the lateral motion of the FW-MAV is unstable but can be stabilized using rolling rate feedback.For CG above the stable region,because of a divergence mode,the system remains unstable even with the rolling rate feedback.Comparison with other works on an FW-MAV based on a quasi-steady aerodynamic model and on insect showed similar characteristics for flapping flight.It is also interesting to note that the asymmetries in body mass and wing kinematics can enlarge the stable region of the system by a non-zero Ixz which approaches the root square of√IxIz,a negative LrNp,and a positive Ix2(Ir+Np).Combining the current result with that of the previous work on longitudinal motion,the most beneficial region of the CG for full 6-DOF flight dynamic stability of hovering KUBeetle was suggested.

关键词： FW-MAV center of gravity flight dynamic stability lateral motion asymmetry computational fluid dynamics bioinspired flight

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Earth Pressure Distribution and Sand Deformation Around Modified Suction Caissons(MSCs) Under Monotonic lateral Loading

引用

China Ocean Engineering 2019年第2期33卷 198-206页

作者： LI Da-yong LI Shan-shan ZHANG Yu-kun CHEN Fu-quan College of Civil Engineering Fuzhou University Key Laboratory of Civil Engineering Disaster Prevention and Mitigation Shandong University of Science and Technology

The modified suction caisson(MSC) is a novel type of foundation for ocean engineering, consisting of a short external closed-top cylinder-shaped structure surrounding the upper part of the regular suction caisson(RSC). The MSC can provide larger lateral bearing capacity and limit the deflection compared with the RSC. Therefore, the MSC can be much more appropriate to use as an offshore wind turbine foundation. Model tests on the MSC in saturated sand subjected to monotonic lateral loading were carried out to investigate the effects of external structure sizes on the sand surface deformation and the earth pressure distribution along the embedded depth. Test results show that the deformation range of the sand surface increases with the increasing width and length of the external structure. The magnitude of sand upheaval around the MSC is smaller than that of the RSC and the sand upheaval value around the MSC in the loading direction decreases with the increasing external structure dimensions. The net earth pressure in the loading direction acting on the internal compartment of the MSC is smaller than that of the RSC at the same embedded depth. The maximum net earth pressure acting on the external structure outer wall in the loading direction is larger than that of the internal compartment, indicating that a considerable amount of the lateral load and moment is resisted by the external skirt structure.

关键词： MSC (modified suction caisson) RSC (regular suction caisson) model tests monotonic lateral loading deformation of sand surface earth pressure distribution

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Interface Electric Field Confinement Effect of High-Sensitivity lateral Ge/Si Avalanche Photodiodes

引用

Tsinghua Science and Technology 2019年第1期24卷 1-8页

作者： Wenzhou Wu Zhi Liu Jun Zheng Yuhua Zuo Buwen Cheng the State Key Laboratory on Integrated Optoelectronics Institute of Semiconductor Chinese Academy of Sciences the College of Materials Science and Opto-Electronic Technology University of Chinese Academy of Sciences

A novel lateral Ge/Si avalanche photodiode without a charge region is investigated herein using device physical simulation. High field is provided by the band-gap barrier and build-in field at the Ge/Si interface in the vertical direction. Modulating the Si mesa thickness(0-0.4 μm) and impurity concentration of the intrinsic Si substrate(1×10^(16)-4×10^(16)cm^(-3)) strengthens the electric field confinement in the substrate region and provides a high avalanche multiplication in the Si region. When the Si mesa thickness is 0.3 μm, and the impurity concentration of the Si substrate is 2×10^(16) cm^(-3), the lateral Avalanche PhotoDiode(LAPD) exhibits a peak gain of 246 under 1.55 μm incident light power of -22.2 dBm, which increases with decreasing light intensity.

关键词： avalanche photodiodes lateral structure electric field confinement high gain

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

SERS-based lateral flow immunoassay of troponin I by using gapenhanced Raman tags

引用

Nano Research 2019年第2期12卷 413-420页

作者： Boris N. Khlebtsov Daniil N. Bratashov Nadezhda A. Byzova Boris B. Dzantiev Nikolai G. Khlebtsov Institute of Biochemistry and Physiology of Plants and Microorganisms Russian Academy of Sciences Saratov 410049 Russia Saratov State University Saratov 410012 Russia A. N. Bach Institute of Biochemistry Research Centre of Biotechnology Russian Academy of Sciences Moscow 119071 Russia

The lateral flow immuno assay (LFIA) has emerged as a powerful tool for rapid scree ning owing to its simplicity and flexibility for detection of various biomarkers. However, conventional LFIA strips have several disadvantages, including limits in quantitative analysis and low sensitivity. Here we developed a novel surface-e nhanced Rama n scatteri ng LFIA based on non spherical gap-e nhanced Raman tags (GERTs), with Raman molecules (RMs) embedded in a 1-nm gap between Au nanorod core and Au shell. Such tags have a strong and uniform surface-enhanced Rama n scattering (SERS) resp on se, an order of mag nitude higher than that of other comm on SERS tags such as Au nano rods, nano stars, Au nano shells with surface-adsorbed RMs, or spherical GERTs with embedded RMs. The feasibility of the tags was dem on strated by the semiqua ntitative and sen sitive detecti on of the heart disease biomarker cardiac tropo nin I (cTnI). GERTs were conjugated with mono clonal antibodies and used for LFIA in the same way as ordinary functionalized colloidal gold. The presenee of the target antigen, cTnI, was identified by Raman microscopy mapping of the test zone. With the SERS-based LFIA, the limit of cTnI detection was about 0.1 ng/mL. This value is within the diagnostic range of cTnI in the blood serum of patients with heart infarction and is 30 times lower than that of the colorimetric LFIA test using the same antibodies and either GERTs or colloidal gold as labels.

关键词： surface-enhanced Raman scattering (SERS) lateral flow immunoassay Au core/shell nanorods gap-enhanced Raman tags cardiac troponin I

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

STRAIN ANALYSIS OF lateral EXTRUSION PROCESS

引用

中国有色金属学会会刊：英文版 1999年第1期9卷 91-94页

作者： Liu, Zuyan Wang, Erde Harbin Inst of Technology Harbin China

ＩＮＴＲＯＤＵＣＴＩＯＮＩｎｒｅｃｅｎｔｙｅａｒｓ，ａｎｅｗｋｉｎｄｏｆｍｅｔｈｏｄ，ｅｑｕａｌｃｒｏｓｓｅｃｔｉｏｎｌａｔｅｒａｌｅｘｔｒｕｓｉｏｎ（ＥＣＳＬＥ），ｈａｓｂｅｅｎｓｕｃｃｅｓｆｕｌｙｕｓｅｄｔｏ... 详细信息

ＩＮＴＲＯＤＵＣＴＩＯＮＩｎｒｅｃｅｎｔｙｅａｒｓ，ａｎｅｗｋｉｎｄｏｆｍｅｔｈｏｄ，ｅｑｕａｌｃｒｏｓｓｅｃｔｉｏｎｌａｔｅｒａｌｅｘｔｒｕｓｉｏｎ（ＥＣＳＬＥ），ｈａｓｂｅｅｎｓｕｃｃｅｓｆｕｌｙｕｓｅｄｔｏｍａｋｅｕｌｔｒａｆｉｎｅｇｒａ...

关键词： equal cross section lateral extrusion finite element simulation strain equivalent true strain

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

BTO/P(VDF-TrFE) Nanofiber-based Artificial lateral Line Sensor with Drag Enhancement Structures

引用

Journal of Bionic Engineering 2020年第1期17卷 64-75页

作者： Zhiqiang Ma Yuanhang Xu Yonggang Jiang Xiaohe Hu Deyuan Zhang Institute of Bionic and Micro-Nano Systems School of Mechanical Engineering and AutomationBeihang UniversityBeijing 100191China Beijing Advanced Innovation Center for Biomedical Engineering Beihang UniversityBeijing 100191China

A flexible Artificial lateral Line(ALL)sensor is presented in this paper,featuring a barium titanate/polyvinylidene fluoride?trifluoroethylene[BTO/P(VDF?TrFE)]nanofiber mat,a hydrogel cupula,and a constriction structure in the canal..The excellent piezoelectric performance of the BTO/P(VDF-TrFE)nanofiber,superior to that of a pristine P(VDF-TrFE)nanofiber,helps improve the sensitivity of the ALL sensor.The hydrogel cupula imitating the cupula in a fish lateral line system enhances the ALL sensitivity through a material-induced drag enhancement mechanism.The constriction mimics the diminution structure found in fish canal lateral line systems,endowing the canal ALL sensor with enhanced sensitivity through a structure-induced drag enhancement mechanism.The contributions of the hydrogel cupula and constriction structure in offering an enhanced sensing performance are studied experimentally,in comparison with conventional ALL sensors.The constriction structure in the canal helps modify the frequency response of the canal ALL sensor,i.e.,attenuating low frequencies while amplifying high frequencies.The proposed biomimetic flow sensor is expected to aid in the development of smart skins for underwater robotics applications.

关键词： lateral line flow sensor biomimetics piezoelectric nanofiber enhanced perception

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Experimental and numerical study of the effect of pulsatile flow on wall displacement oscillation in a flexible lateral aneurysm model

引用

Acta Mechanica Sinica 2019年第5期35卷 1120-1129页

作者： L.Z.Mu X.Y.Li Q.Z.Chi S.Q.Yang P.D.Zhang C.J.Ji Y.He G.Gao School of Energy and Power Engineering Dalian University of TechnologyDalian 116024China School of Biomedical Engineering Capital Medical UniversityBeijing 100069China The First Affiliated Hospital of University of Science and Technology of China Hefei 230036China

This study experimentally and numerically investigated the effect of pulsatile flow of different frequencies and outflow resistance on wall deformation in a lateral aneurysm.A method for constructing a flexible aneurysm model was developed,and a self-designed piston pump was used to provide the pulsatile flow conditions.A fluid-structure interaction simulation was applied for comparison with and analysis of experimental findings.The maximum wall displacement oscillation increased as the pulsation frequency and outflow resistance increased,especially at the aneurysm dome.There is an obvious circular motion of the vortex center accompanying the periodic inflow fluctuation,and the pressure at the aneurysm dome at peak flow increased as the pulsatile flow frequency and terminal flow resistance increased.These results could explain why abnormal blood flow with high frequency and high outflow resistance is one of the risk factors for aneurysm rupture.

关键词： lateral aneurysm In vitro experiment Pulsatile flow Wall displacement oscillation Fluid-structure interaction simulation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Optimum lateral extent of soil domain for dynamic SSI analysis of RC framed buildings on pile foundations

引用

Frontiers of Structural and Civil Engineering 2020年第1期14卷 62-81页

作者： Nishant SHARMA Kaustubh DASGUPTA Arindam DEY Department of Civil Engineering Indian Institute of Technology GuwahatiGuwahati 781039India

This article describes a novel approach for deciding optimal horizontal extent of soil domain to be used for finite element based numerical dynamic soil structure interaction(SSI)studies.SSI model for a 12 storied building frame,supported on pile foundation-soil system,is developed in the finite element based software framework,OpenSEES.Three different structure-foundation configurations are analyzed under different ground motion characteristics.lateral extent of soil domain,along with the soil properties,were varied exhaustively for a particular structural configuration.Based on the reduction in the variation of acceleration response at different locations in the SSI system(quantified by normalized root mean square error,NRMSE),the optimum lateral extent of the soil domain is prescribed for various structural widths,soil types and peak ground acceleration levels of ground motion.Compared to the past studies,error estimation analysis shows that the relationships prescribed in the present study are credible and more inclusive of the various factors that influence SSI.These relationships can be readily applied for deciding upon the lateral extent of the soil domain for conducting precise SSI analysis with reduced computational time.

关键词： soil structure interaction optimum lateral extent of soil domain length multi-storyed framed building pile foundation OpenSEES L-K boundaries dynamic analysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Theoretical Distribution of Gutta-percha within Root Canals Filled Using Cold lateral Compaction Based on Numeric Calculus

引用

Journal of Huazhong University of Science and Technology(Medical Sciences) 2016年第4期36卷 588-593页

作者：闵艺宋颖高原 Paul.M.H.Dummer State Key Laboratory of Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine of Ministry of Education School and Hospital of Stomatology Wuhan University State Key Laboratory of Oral Diseases West China College & Hospital of Stomatology Sichuan University School of Dentistry College of Biomedical and Life Sciences Cardiff University

This study aimed to present a new method based on numeric calculus to provide data on the theoretical volume ratio of voids when using the cold lateral compaction technique in canals with various diameters and tapers. Twenty-one simulated mathematical root canal models were created with different tapers and sizes of apical diameter, and were filled with defined sizes of standardized accessory gutta-percha cones. The areas of each master and accessory gutta-percha cone as well as the depth of their insertion into the canals were determined mathematically in Microsoft Excel. When the first accessory gutta-percha cone had been positioned, the residual area of void was measured. The areas of the residual voids were then measured repeatedly upon insertion of additional accessary cones until no more could be inserted in the canal. The volume ratio of voids was calculated through measurement of the volume of the root canal and mass of gutta-percha cones. The theoretical volume ratio of voids was influenced by the taper of canal, the size of apical preparation and the size of accessory gutta-percha cones. Greater apical preparation size and larger taper together with the use of smaller accessory cones reduced the volume ratio of voids in the apical third. The mathematical model provided a precise method to determine the theoretical volume ratio of voids in root-filled canals when using cold lateral compaction.

关键词： lateral compaction Volume ratio of void apical preparation gutta-percha

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A Model of Tangential Contact Damping Considering Asperity Interaction and lateral Contact

引用

Acta Mechanica Solida Sinica 2018年第6期31卷 758-774页

作者： W.P.Fu Z.Q.Gao W.Wang J.B.Wu School of Mechanical and Precision Instrument Engineering Xi'an University of TechnologyXi'an 710048 China

A precise tangential contact damping model is proposed,which includes the lateral contact of the upper-lower asperities and the interaction of adjacent asperities.The effects of the normal static preload,frequency,and amplitude of tangential displacement on the tangential contact damping were analyzed by simulation,respectively.Furthermore,the results of simulation are verified by experiment.The tangential contact damping of considering the interaction and lateral contact of asperity is very close to the experimental results.

关键词： Asperity lateral contact Interaction Tangential contact damping

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：