检索结果-内蒙古大学图书馆

Fluid Inertia Force Effects in Hydromagnetic Circular Stepped Squeeze Films

Journal of the Chinese Society of mechanical Engineers, Transactions of the Chinese Institute of Engineers, Series C/Chung-Kuo Chi Hsueh Kung Ch'eng Hsuebo Pao 2018年第4期39卷 419-425页

作者： Lin, Jaw-Ren Chu, Li-Ming Hung, Tzu-Chen Department of Mechanical Engineering Nanya Institute of Technology Taoyuan32091 Taiwan Department of Applied Science Interdisciplinary Program of Green and Information Technology National Taitung University 95092 Taiwan Department of Mechanical Engineering National Taipei University of Technology 10608 Taiwan

On the basis of the hydromagnetic flow theory, an inertia hydromagnetic lubrication equation has been derived for circular stepped squeeze film disks by applying the momentum integral method. Analytical solution of the film pressure, the load capacity and the squeeze film time are obtained in the present paper. It is found that the hydromagnetic squeeze film including the influences of fluid inertia forces provides an increased load capacity as well as a longer squeeze film time as compared to the non-inertia non-conducting-lubricant case. The improved squeeze film characteristics are further emphasized for the circular stepped disks operating at larger values of the density parameter and the magnetic Hartmann number, and smaller values of the radius ratio and the step height ratio. © 2018, Chinese mechanical engineering Society. All right reserved.

关键词： Magnetohydrodynamics

来源：评论

学校读者我要写书评

暂无评论

Rigid-Soft Interactive Learning for Robust Grasping*

arXiv

引用

arXiv 2020年

作者： Yang, Linhan Wan, Fang Wang, Haokun Liu, Xiaobo Liu, Yujia Pan, Jia Song, Chaoyang Southern University of Science and Technology University of Hong Kong Shenzhen Guangdong518055 China AncoraSpring Inc. SUSTech Institute of Robotics Southern University of Science and Technology Shenzhen Guangdong518055 China Department of Mechanical and Energy Engineering Southern University of Science Shenzhen Guangdong518055 China Department of Computer Science University of Hong Kong Hong Kong Department of Mechanical and Energy Engineering Southern University of Science and Technology Shenzhen Guangdong518055 China

Inspired by widely used soft fingers on grasping, we propose a method of rigid-soft interactive learning, aiming at reducing the time of data collection. In this paper, we classify the interaction categories into Rigid-Rigid, Rigid-Soft, SoftRigid according to the interaction surface between grippers and target objects. We find experimental evidence that the interaction types between grippers and target objects play an essential role in the learning methods. We use soft, stuffed toys for training, instead of everyday objects, to reduce the integration complexity and computational burden and exploit such rigid-soft interaction by changing the gripper fingers to the soft ones when dealing with rigid, daily-life items such as the Yale-CMU-Berkeley (YCB) objects. With a small data collection of 5K picking attempts in total, our results suggest that such Rigid-Soft and Soft-Rigid interactions are transferable. Moreover, the combination of different grasp types shows better performance on the grasping test. We achieve the best grasping performance at 97.5% for easy YCB objects and 81.3% for difficult YCB objects while using a precise grasp with a two-soft-finger gripper to collect training data and power grasp with a four-soft-finger gripper to test. Copyright © 2020, The Authors. All rights reserved.

关键词： Learning systems

来源：评论

学校读者我要写书评

暂无评论

Modelling and Dynamic Tracking Control of Industrial Vehicles with Tractor-trailer Structure

Modelling and Dynamic Tracking Control of Industrial Vehicle...

引用

2019 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)

作者： Hongchao Zhao Zhe Liu Zhiqiang Li Shunbo Zhou Wen Chen Chuanzhe Suo Yun-Hui Liu Department of Mechanical and Automation Engineering T Stone Robotics Institute and The Chinese University of Hong Kong Shatin HKSAR

Existing works on control of tractor-trailers systems only consider the kinematics model without taking dynamics into account. Also, most of them treat the issue as a pure control theory problem whose solutions are difficult to implement. This paper presents a trajectory tracking control approach for a full-scale industrial tractor-trailers vehicle composed of a carlike tractor and arbitrary number of passive full trailers. To deal with dynamic effects of trailing units, a force sensor is innovatively installed at the connection between the tractor and the first trailer to measure the forces acting on the tractor. The tractor's dynamic model that explicitly accounts for the measured forces is derived. A tracking controller that compensates the pulling/pushing forces in real time and simultaneously drives the system onto desired trajectories is proposed. The propulsion map between throttle opening and the propulsion force is proposed to be modeled with a fifth-order polynomial. The parameters are estimated by fitting experimental data, in order to provide accurate driving force. Stability of the control algorithm is rigorously proved by Lyapunov methods. Experiments of full-size vehicles are conducted to validate the performance of the control approach.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Data-driven geometric system identification for shape-underactuated dissipative systems

arXiv

引用

arXiv 2020年

作者： Bittner, Brian Hatton, Ross L. Revzen, Shai Robotics Institute University of Michigan Ann Arbor United States Johns Hopkins University Applied Physics Lab LaurelMD United States Institute School of Mechanical Industrial and Manufacturing Engineering Oregon State University Corvallis United States Electrical Engineering and Computer Science Department University of Michigan Ann Arbor United States

Modeling system dynamics becomes challenging when the properties of individual system components cannot be directly measured, and often requires identification of properties from observed motion. In this paper, we show that systems whose movement is highly dissipative have features which provide an opportunity to more easily identify models and more quickly optimize motions than would be possible with general techniques. Geometric mechanics provides means for reduction of the dynamics by environmental homogeneity, while the dissipative nature minimizes the role of second order (inertial) features in the dynamics. Here we extend the tools of geometric system identification to "Shape-Underactuated Dissipative Systems (SUDS)" – systems whose motions are more dissipative than inertial, but whose actuation is restricted to a subset of the body shape coordinates. Many animal motions are SUDS, including micro-swimmers such as nematodes and flagellated bacteria, and granular locomotors such as snakes and lizards. Many soft robots are also SUDS, particularly robots that incorporate highly damped series elastic actuators to reduce the rigidity of their interactions with their environments during locomotion and manipulation. We motivate the use of SUDS models, and validate their ability to predict motion of a variety of simulated viscous swimming platforms. For a large class of SUDS, we show how the shape velocity actuation inputs can be directly converted into torque inputs, suggesting that systems with soft pneumatic or dielectric elastomer actuators can be modeled with the tools presented. Based on fundamental assumptions in the physics, we show how our model complexity scales linearly with the number of passive shape coordinates. This scaling offers a large reduction on the number of trials needed to identify the system model from experimental data, and may reduce overfitting. The sample efficiency of our method suggests its use in modeling, control, and optimization in ro

关键词： Energy dissipation

来源：评论

学校读者我要写书评

暂无评论

Synthesis and characterization of activated carbon derived from rubberwood sawdust by using KOH/KMnO4 as multiple function activation agents

引用

IOP Conference Series: Materials Science and engineering 2021年第1期1163卷

作者： S Phainuphong J Taweekun T Theppaya K Maliwan Energy Technology Program Faculty of Engineering Prince of Songkla University Hatyai Songkhla 90112 Thailand Department of Mechanical and Mechatronics Engineering Faculty of Engineering Prince of Songkla University Hatyai Songkhla 90112 Thailand.

This research is focused on the effects of impregnation ratios using KOH/KMnO4 as multiple function activation agents on microporous of activated carbon. Rubberwood sawdust, the waste from wood processing industry, was used as a raw material in synthesis of activated carbon by chemical activation. The rubberwood sawdust was carbonized at 400 °C for 1 hour under an inert atmosphere to produce char. Chars were impregnated with different proportions of KOH and KMnO4. Impregnation time for each mixture proportion (Char: KOH: KMnO4) was 24 hours before activation for 3 hours at 800 °C. The surface area, pore volume, micropore volume, pore size distribution, porous structure, and adsorption isotherm were examined and considered as the properties of activated carbon. The results showed that the activated carbon with an impregnation ratio of 10:10:5, 10:30:0, and 10:30:5 have the surface area 750.89 m 2/g, 1574.39 m 2/g, and 1346.10 m 2/g, respectively. The pore volume and micropore volume were in the range between 0.3289-0.6405 cm 3/g and 0.1920-0.3533 cm 3/g. The average pore sizes were 1.75 nm, 1.63 nm, and 1.65 nm, respectively. These synthesized activated carbons were characterized as type I isotherm and microporous solids.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Computational investigation into resistance characteristics of a full-scale pusher-barge system

引用

AIP Conference Proceedings 2022年第1期2543卷

作者： Ahmad Fitriadhy Nur Amira Adam Raja Noor Syaheeda Faisal Mahmuddin Suandar Baso Mohd Azlan Musa Anuar Abu Bakar Mohd Asamudin A. Rahman Mohd Hairil Mohd 1)Program of Naval Architecture Faculty of Ocean Engineering Technology and Informatics Universiti Malaysia Terengganu 21030 Kuala Terengganu Terengganu Malaysia 2)Program of Boat Making Technology Department of Mechanical Kolej Vokasional Pasir Gudang Johor Malaysia 3)Department of Marine Engineering Faculty of Engineering Hasanuddin University Jalan Poros Malino km. 6 Bontomarannu 92172 Gowa Sulawesi Selatan Indonesia 4)Department of Naval Architecture Faculty of Engineering Hasanuddin University Jalan Poros Malino km. 6 Bontomarannu 92172 Gowa Sulawesi Selatan Indonesia

In the presence of hydrodynamic motion interference between pusher and multiple barge configurations, a reliable investigation allowing an accurate prediction of her total resistance is obviously required. To achieve such objective, the Computational Fluid Dynamics (CFD) approach is then proposed to predict the total ship’s resistance of a pusher-barge system in the calm water condition. The various barge’s configurations incorporated with various Froude numbers (Fr) have been considered in the computational simulation incorporated with the full-scale dimension of the pusher-barge. In general, the CFO results revealed that the total resistances of the various configurations of the pusher-barge system had a qualitatively good agreement with the experimental model test results. Merely, the increase of Froude number (Fr=0.128 to 0.308) was proportional to the magnitude of total resistance. In addition, the pusher-barge system of the 33BP configuration provides the highest resistance as compared to others. It should be noted here that the pusher-barges configurations led to the susceptible effect to the total ship’s resistance which resulted in remarkable increase of the effective power values as the substituting their arrangements from the longitudinal configurations and to the lateral ones. This finding provides a very valuable insight aimed at selecting the proper pusher-barge configurations towards reducing the total ship’s resistance.

关键词：

来源：评论

学校读者我要写书评

暂无评论

A study on activated carbon from Borassus flabellifer shell by chemical activation with potassium hydroxide for supercapacitor

引用

IOP Conference Series: Materials Science and engineering 2021年第1期1163卷

作者： C. Chaitammachok J. Taweekun K. Maliwan T. Theppaya Energy Technology Program Faculty of Engineering Prince of Songkla University 90112 Hat Yai Songkhla Thailand department of Mechanical Engineering Faculty of Engineering Prince of Songkla University 90112 Hat Yai Songkhla Thailand

The supercapacitor is significant in daily life. It is an alternative option that can storage energy. This research focused on studying the effect of Potassium hydroxide concentration content increasing surface area of the Borassus flabellifer shell charcoal (BFC), power density and energy density of activated carbon as electrode and cycles. Borassus flabellifer shell as agricultural waste was carbonized with tube furnace at nitrogen atmosphere by heated at 400 °C for 1 hour. Activated carbon with KOH (the mass ratio of KOH: BFC; 1:1, 1:2, 1:3, 4:1 and 5:1) (BAC) was heated at 900 °C for 2 hours. The results of the research show that suitable concentration of KOH: BFC to activated with higher pore volume and higher surface area. BAC- 5 (5:1) is the highest pore volume of 1679.61 m 2/g and the highest pore volume of 0.737 (cm 3/g) but BAC-4 (4:1) is the best because it has a similar surface area and is economical, the highest pore volume of 1607.092 m 2/g and the highest pore volume of 0.686 (cm 3/g). BAC-1, BAC-2, BAC-3, BAC-4 and BAC-5 have average pore diameters, respectively, around of 1.609 nm., 1.641 nm., 1.742 nm., 1.708 nm. and 1.754 nm. The average pore size of products is microporous.

关键词：

来源：评论

学校读者我要写书评

暂无评论

The effect of synthesized rice husk ash to compressive strength of reactive powder concrete containing quartzite powder

引用

AIP Conference Proceedings 2022年第1期2663卷

作者： Yulius Rief Alkhaly Abdullah Husaini Muttaqin Hasan 1Doctoral Program School of Engineering Universitas Syiah Kuala (USK) Jl. Syech Abdurrauf No. 7 Darussalam Banda Aceh 23111 Indonesia 2Civil Engineering Department Faculty of Engineering Universitas Malikussaleh Bukit Indah Lhokseumawe 24315 Indonesia 3Civil Engineering Department Faculty of Engineering Universitas Syiah Kuala (USK) Jl. Syech Abdurrauf No. 7 Darussalam Banda Aceh 23111 Indonesia 4Mechanical Engineering Department Faculty of Engineering Universitas Syiah Kuala (USK) Jl. Syech Abdurrauf No. 7 Darussalam Banda Aceh 23111 Indonesia

The very high strength of Reactive Powder Concrete (RPC) is possible to produce due to the availability of a pozzolanic material in the mixture and application of the packing density method to obtain the optimum density of the mixture proportions. Rice husk ash is a natural source of high silica (SiO2) with readiness in huge volumes. In this study, the RPC mixtures were produced from a fixed content of 25% silica fume of the cement weight combined with synthesized rice husk ash (SRHA) of 10%, 20%, and 30% by cement weight. Mix proportions were obtained by using the Modified Andreassen Packing Model method. This study aims to determine the width of slump flow and compressive strength under normal and steam curing of RPC with low cement content (650 kg/m3). The results demonstrated that the intermix of silica fume with synthesized rice husk ash up to 30% provides an advance on the slump flow width and compressive strength of RPC containing local quartzite powder under normal and steam curing.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Cover Picture: Furin-Mediated Self-Assembly of Olsalazine Nanoparticles for Targeted Raman Imaging of Tumors (vol 59, pg 22408, 2020)

引用

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION 2021年第8期60卷 3851-3851页

作者： Lin, L. Liu, T. Xiao, J. Li, H. Wei, P. Gao, D. Nan, B. Si, R. Wang, G. Bao, X. The Russell H. Morgan Department of Radiology and Radiological Science Division of MR Research The Johns Hopkins University School of Medicine Baltimore MD USA Cellular Imaging Section and Vascular Biology Program Institute for Cell Engineering The Johns Hopkins University School of Medicine Baltimore MD USA Department of Chemistry University of Science and Technology of China Hefei Anhui China Department of Mechanical Engineering The Johns Hopkins University Baltimore MD USA Department of Chemistry Indian Institute of Technology Delhi Hauz Khas New Delhi 110016 India Department of Oncology The Johns Hopkins University School of Medicine Baltimore MD USA

Single olsalazine molecules can be self-assembled into nanoparticles by the tumor-overexpressed enzyme furin following a 2-cyanobenzothiazole (CBT)-mediated biocompatible click condensation reaction and pi-pi stacking, as demonstrated by Ishan Barman, Jeff W. M. Bulte et al. in their Communication on page 3923. These intracellular nanoparticles provide a differential Raman scattering signature, allowing highly specific imaging of cancer cells in vitro and in vivo.+

关键词： furin nanoparticles olsalazine Raman spectroscopy self-assembly

来源：评论

学校读者我要写书评

暂无评论

Development and Characterization of a PCB-Based Microfluidic YChannel*

Development and Characterization of a PCB-Based Microfluidic...

引用

Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： Panagiotis Kassanos Florent Seichepine Ioannis Kassanos Guang-Zhong Yang Hamlyn Centre Institute of Global Health Innovation Imperial College London London UK Mechanical Engineering Department National Technical University of Athens Athens Greece Hamlyn Centre and is now with the Institute of Medical Robotics Shanghai Jiao Tong University China

ISBN: (数字)9781728119908

ISBN: (纸本)9781728119915

Since the introduction of microfluidics in the 1990s, the community has investigated numerous methods for their fabrication. However, there is interest for their inexpensive rapid prototyping. PCB technology as a low-cost, massfabrication approach for the realization of sensors has attracted attention, while its use for microfluidics is also gaining ground. In this paper the development and characterization of a microfluidic Y-channel is presented. The proposed design and assembly process for realizing the device is described in detail and the flow rate and mixing within the microchannel are characterized, demonstrating the feasibility of the proposed novel technology for lab-on-PCB devices.

关键词： Microfluidics Scanning electron microscopy Three-dimensional displays Fabrication Microchannels Lasers

来源：评论

学校读者我要写书评

暂无评论

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

请选择保存的检索档案：

请选择收藏分类：

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

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

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：