检索结果-内蒙古大学图书馆

Effective Model-Based systems engineering 1

1000年

作者： John M. Borky Thomas H. Bradley

暂无评论

Feasibility study of novel magnetic compaction force assisted additive manufacturing (MCFA-AM) methodology for continuous carbon fiber reinforced polymer (C-CFRP) composites

Feasibility study of novel magnetic compaction force assiste...

引用

SAMPE 2019 Conference and Exhibition

作者： Ranabhat, Bikash Kirmse, Sebastian Hsiao, Kaung-Ting University of South Alabama Department of Mechanical Engineering 150 Jaguar Drive Shelby Hall Suite 3130 MobileAL36608 United States Department of Mechanical Engineering United States Systems Engineering Program United States

ISBN: (纸本)9781934551301

Composite parts manufactured by the current additive manufacturing (AM) methods are inferior in strength and stiffness compared to traditional composite manufacturing. Major issues include voids, physical gaps at layer/layer interface, and low reinforcing fiber content. This paper experimentally examined the feasibility of a patent-pending novel method, Magnetic Compaction Force Assisted-Additive Manufacturing (MCFA-AM), that utilized a magnetic compaction force to print and support curve-shaped continuous carbon fiber reinforced polymer (C-CFRP) composites in free space without any mold. C-CFRP prepreg tapes were fed through a magnet-assisted roller-like-setting, which was a part of the 3D printing head, and consolidated with a magnetic compaction pressure of 0.21 MPa in this feasibility trial. Short beam shear tests (ASTM D2344) showed that the 0.21 MPa MCFA-AM samples’ interlaminar shear strength (ILSS) was 8 % and 9 % stronger and 7% weaker compared with the C-CFRP samples manufactured by the hand layup, the Tension-Tape-Placement-Without Compaction-AM, and the Out-Of-Autoclave Vacuum-Bag-Only (OOA-VBO) methods, respectively. Microscopic observations showed the size and number of voids were significantly reduced by the magnetic compaction. Finally, it demonstrated that printing stiff, strong, and complex shaped C-CFRP parts with great freedom can be done within a few minutes with this exciting AM-Composites technology advance. Copyright 2019 by Bikash Ranabhat et al. Published by Society for the Advancement of Material and Process engineering with permission.

关键词： 3D printers

来源：评论

学校读者我要写书评

暂无评论

Investigating the effect of cryogenic pre-cooling on the friction stir processing of AZ31B

Investigating the effect of cryogenic pre-cooling on the fri...

引用

World Congress on engineering, WCE 2014

作者： Ammouri, Ali H. Kridli, Ghassan T. Ayoub, George Hamade, Ramsey F. Mechanical Engineering Department American University of Beirut 11-0236 Beirut Lebanon Department of Industrial and Manufacturing Systems Engineering University of Michigan Dearborn United States Mechanical Engineering Program Texas A and M University United States

ISBN: (纸本)9789881925350

This manuscript aims to investigate the effect of cryogenic in-process cooling via liquid nitrogen on the outcomes of the friction stir processing (FSP) of twin roll cast (TRC) magnesium alloy AZ31B. Friction stir processing was performed on 3mm thick sheets of TRC AZ31B at a wide range of processing parameters. The tool rotational speed was varied between 600 RPM and 2000 RPM while the tool feed rate varied between 75 mm/min and 900 mm/min. Thrust force and torque values were experimentally measured using a 4-component dynamometer. Temperature measurements were monitored during the different tests using Infrared sensors and thermocouples. The microstructure of processed samples was observed using optical microscopy. It was found that thrust force and torque values of the pre-cooled samples were 5% higher than those of the room temperature samples due to the material hardening induced by the cooling effect. Finer and more homogenous microstructure was observed for the pre-cooled samples when compared with samples processed at room temperature. The average grain size of pre-cooled samples was predicted using a relation -previously introduced by the authors- that relate grain size and the Zener-Hollomon parameter for TRC AZ31B. This equation was found to correctly predict grain diameter for in-line cooled FSP AZ31B samples at temperatures lower than room temperature.

关键词： Friction

来源：评论

学校读者我要写书评

暂无评论

Integrating matlab and simulink in an advanced engineering mechanics course

Integrating matlab and simulink in an advanced engineering m...

引用

2004 ASME International mechanical engineering Congress and Exposition, IMECE 2004

作者： Dabney, James B. Ghorbel, Fathi H. Systems Engineering Program University of Houston - Clear Lake Houston TX United States Department of Mechanical Engineering Rice University Houston TX United States

ISBN: (纸本)0791847233

An advanced engineering mechanics course teaches students to analyze and model a variety of dynamical systems using Newtonian and Lagrangian mechanics approaches. The modeling task typically produces nonlinear differential equations that are best solved numerically. In order to prepare students to competently solve these systems numerically, the students must master a suitable programming environment. This mastery is achieved incrementally throughout the semester. This paper describes a successful approach to developing the necessary programming skills, culminating in a course project in which the students model a complex dynamical system and produce a graphical animation allowing visualization of dynamical behavior. The paper also describes two typical course projects that have been successfully completed by advanced undergraduate and beginning graduate students. Copyright 2004 by ASME.

关键词： engineering education

来源：评论

学校读者我要写书评

暂无评论

Improvement of product strength and press formability of Al-Mg-Si alloy sheets by resistance heat treatment and artificial aging

引用

Keikinzoku/Journal of Japan Institute of Light Metals 2006年第6期56卷 313-316页

作者： Ishiguro, Minoru Maki, Seijiro Mori, Ken-Ichiro Doctoral Program of Mechanical and Structural System Engineering Toyohashi University of Technology 1-1 Hibarigaoka Tempaku-cho Toyohashi-shi Aichi 441-8580 Department of Production Systems Engineering Toyohashi University of Technology Toyohashi-shi Aichi

A treatment consisting of resistance heat treatment and artificial aging was developed to improve the product strength and press formability of Al-Mg-Si alloy sheets having paint bake hardenability used for automobile body panels. In this treatment, the sheets are re-solution heat-treated by resistance heating and water quenching just before the press forming. The formed sheets are artificially aged just after the press forming to increase the product strength. In the experiment, Al-0.60%Si-0.74%Mg (A6061) alloy sheets were chosen. The solution heat treatment of the sheets was sufficiently accomplished by the rapid resistance heat treatment, and the press formability of the sheets was improved. The hardness of formed products is increased by the artificial aging and paint bake hardening. It was found that the present heat treatment is effective in improving the product strength and press formability of the Al-Mg-Si alloy sheets having the paint bake hardenability.

关键词： Aluminum alloys

来源：评论

学校读者我要写书评

暂无评论

FORMATION AND BREAKING OF SIDE-CURL DOMINATED SHORT-SPIRAL CHIPS

FORMATION AND BREAKING OF SIDE-CURL DOMINATED SHORT-SPIRAL C...

引用

ASME 1997 International mechanical engineering Congress and Exposition, IMECE 1997 - Manufacturing Science and engineering

作者： Li, Zhenjia Qu, Guimin Xu, Yihong Rong, Yiming Department of Mechanical Engineering Harbin University of Science and Technology' China Manufacturing Systems Program Southern Illinois University Carbondale United States

ISBN: (纸本)9780791826799

In this paper, the formation of side-curl dominated chips IS first discussed, as well as the side-curl radius. The chip width and thickness in 3-D side-surl is studied for the side-curl radius prediction. The formation and and breaking of side-curled short-spiral chips in metal cutting is particularly studied. It is found that the collision of the swinging chip and the unmachined workpiece surface or tool holder flank surface plays an important role in chip breaking. Based on a force analysis, a chip breaking criterion is established and the chip length is estimated. The relationship of chip breaking length and cutting parameters is derived and verified by experiment results, which can be used in chip length prediction. © 1997 American Society of mechanical Engineers (ASME). All rights reserved.

关键词： Metal cutting

来源：评论

学校读者我要写书评

暂无评论

FPGA-based image processing for omnidirectional vision on mobile robots 11

FPGA-based image processing for omnidirectional vision on mo...

引用

24th Symposium on Integrated Circuits and systems Design, SBCCI2011

作者： Yudi Mori, Jones Mũoz Arboleda, Daniel Arias Garcia, Janier Llanos Quintero, Carlos Motta, José Mechatronic Systems Graduate Program - PPMEC Department of Mechanical Engineering University of Brasilia 70910-900 Brasilia D.F. Brazil

ISBN: (纸本)9781450308281

Omnidirectional vision systems have been used for mobile robots localization and navigation, taking advantage of a panoramic view for detecting objects. This paper presents a pipelined hardware architecture for image processing using a low cost omnidirectional vision system, which was calibrated using a three-order polynomial interpolation. An Altera Cyclone II FPGA device was used for implementing the hardware architectures, which have been described in both VHDL and Verilog hardware description languages. The entire system is composed of a spherical mirror, an 800x480 pixels camera connected to the FPGA, a spatial convolution filter for edge enhancement, a hardware architecture for estimating the distance of real objects and a touch screen display as user interface. Synthesis results point out that the image processing algorithms are effectively implemented in hardware whereas test results demonstrate that the proposed hardware architectures in FPGAs are suitable for mobile robot applications in which the distance among objects or other robots must be computed. Execution time results demonstrate that the proposed hardware architecture achieves a speed-up factor of 61 in comparison with a desktop software solution based on a xPC Target real time operating system. © 2011 ACM.

关键词： Field programmable gate arrays (FPGA)

来源：评论

学校读者我要写书评

暂无评论

Model-based torque control of piezoelectric ultrasonic motors

Model-based torque control of piezoelectric ultrasonic motor...

引用

2006 ASME International mechanical engineering Congress and Exposition, IMECE2006

作者： Dabney, James B. Harman, Thomas L. Ghorbel, Fathi H. Chakkungal, Joseph J. Systems Engineering Program University of Houston - Clear Lake Houston TX United States Department of Mechanical Engineering Rice University Houston TX United States

ISBN: (纸本)0791837904

Traveling wave piezoelectric ultrasonic motors (PUMs) are ideal actuators for a variety of important applications including medical and space robotics, haptic interfaces, and positioning devices. Consisting of a single moving part, the motors are much simpler mechanically than other drive systems that require transmissions and brakes. Many potential PUM applications require accurate real-time control of output torque, which is difficult due to the highly nonlinear PUM dynamics. This paper presents an algorithm that adjusts PUM drive signal frequency to achieve output torque control throughout the speed range of a typical commercial PUM. Copyright © 2006 by ASME.

关键词： Electric motors

来源：评论

学校读者我要写书评

暂无评论

Numerical and Experimental Study on Flow Effects of Pneumatic Proportional Pressure Valve

引用

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 2020年第2期41卷 149-158页

作者： Shieh, Tzong-Hann Yeh, Chun-Liang Chen, Yu-Li Hsiao, Charng-Chin Department of Aerospace and Systems Engineering Feng Chia University 100 Wenhwa Rd. Seatwen Taichung Taiwan Ph.D. Program of Mechanical and Aeronautical Engineering Feng Chia University 100 Wenhwa Rd. Seatwen Taichung Taiwan

This study developed a novel system for the measurement of pressure within an SMC-ITV2030-012BL pneumatic proportional pressure valves. We also constructed a precise three-dimensional structure of the channel within the valve to examine the aerodynamic characteristics of the internal flow field using the finite volume method and Reynolds-averaged Navier-Stokes equations. We first compared the aerodynamic characteristics resulting from opening the valve 70% using completely or partially encrypted grid models. We then considered various wall structures at the inlet and outlet of the flow channel with the same valve opening. Finally, we compared the results of simulation and experiments of the flow field within the valve. Finally, we investigated the flow field characteristics when the valve was opened 90%, 70%, and 50%. Experiment and simulation results show that the aerodynamic characteristics of the flow field are influenced by the wall structures of the valve and the opening of the valve as well as the grid encryption method that is employed. © 2020, Chinese mechanical engineering Society. All right reserved.

关键词： Finite volume method

来源：评论

学校读者我要写书评

暂无评论

Preparing future entrepreneurs: reflections about the COVID-19 impacts on the entrepreneurial potential of Brazilian students

引用

Journal of Work-Applied Management 2021年第2期13卷 277-283页

作者： Cazeri, Gustavo T. Anholon, Rosley Rampasso, Izabela Simon Quelhas, Osvaldo L.G. Leal Filho, Walter School of Mechanical Engineering State University of Campinas Campinas Brazil PNPD/CAPES Program Doctoral Program in Sustainable Management Systems Federal Fluminense University Niterói Brazil Master Program in Management Systems Doctoral Program in Sustainable Management Systems Federal Fluminense University Niterói Brazil Faculty of Life Sciences Hamburg University of Applied Sciences Hamburg Germany

Purpose: This viewpoint aims to present reflections on the coronavirus disease 2019 (COVID-19) pandemic scenario and the entrepreneurial potential of Brazilian students. Guidelines are proposed to support debates in the academic environment and better prepare future entrepreneurs to the labour market. Design/methodology/approach: Since this is a viewpoint article, some statements presented here are characterised by the authors' opinions. However, for a better foundation, bibliographic research related to the theme was carried out. Findings: In the authors' point of view, the COVID-19 pandemic scenario may negatively influence the decisions of Brazilian students that are characterised as potential future entrepreneurs. Educators can use the guidelines presented here to conduct debates with students in order to clarify aspects related to profile, behaviour and other issues. Originality/value: By understanding better entrepreneurial aspects in the COVID-19 pandemic scenario, Brazilian students can make better decisions. This initiative will contribute to future success in the Brazilian entrepreneurial activity and national economy. © 2021, Gustavo T. Cazeri, Rosley Anholon, Izabela Simon Rampasso, Osvaldo L.G. Quelhas and Walter Leal Filho.

关键词： Brazilian higher education institutions COVID-19 pandemic Entrepreneurial activity Labour market

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：