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design and Analysis of a 0.01-to-6GHz 31dBm-P1dB 31.5%-PAE Distributed Power Amplifier in 0.25-μm GaAs Technology

2006年中国机械工程学会年会暨中国工程院机械与运载工程学部首届年会

作者： ZHANG Chanjun, YANG Mingzhong School of Mechatronic Engineering, Wuhan University of Technology, Wuhan 430070

As the foundation of Enterprise Application Integration (EAI) system, the fundamental contents of product design can be divided into five parts: appearance design, function design, cost design, techno

关键词： EAI concurrent design resources organizing model full lifecycle.

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Chinese Journal of Electronics 2021年第3期30卷 549-555页

作者： MENG Fanyi LIU Cha HU Jianquan MOU Shouxian MA Kaixue School of Microelectronics Tianjin University Smarter Micro Company School of Physics University of Electronic Science and Technology of China

This paper presents the design and analysis of a distributed power amplifier with 6-d B bandwidth from 10 MHz to 6 GHz. To meet the stringent targeted specification, the concurrent design and analysis are carefully performed with optimizations in both passive and active devices. The gate capacitive division technique is proposed and proven theoretically of bandwidth extension effect and power efficiency enhancement. To validate the theory, a prototype is designed in a 0.25-μm Ga As technology. The fabricated amplifier chip is packaged in an evaluation cavity of SMA connectors. The measurement shows an average power gain of 15 d B, OP1 d Band PSAT of 31 d Bm and 32.6 d Bm at 3 GHz, and PAE at OP1 d Band PSAT points are 31.5% and 43.7% respectively. To the best of authors' knowledge, the amplifier achieves the highest Power-added efficiency(PAE) among the similar Ga As amplifiers.

关键词： gallium arsenide III-V semiconductors gate capacitive division technique evaluation cavity microwave amplifiers bandwidth extension effect fabricated amplifier chip power efficiency enhancement network synthesis distributed amplifiers frequency 10.0 MHz to 6.0 GHz efficiency 31.5 percent active devices network analysis average power gain passive devices SMA connectors electric connectors circuit optimisation distributed power amplifier UHF power amplifiers GaAs GaAs technology power-added efficiency GaAs amplifiers size 0.25 mum concurrent design

concurrent topology optimization for minimization of total mass considering load-carrying capabilities and thermal insulation simultaneously

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Acta Mechanica Sinica 2018年第2期34卷 315-326页

作者： Kai Long Xuan Wang Xianguang Gu Beijing Key Laboratory of Energy Safety and Clean Utilization North China Electric Power University State Key Laboratory for Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics Dalian University of Technology School of Automobile and Traffic Engineering Hefei University of Technology

The present work introduces a novel concurrent optimization formulation to meet the requirements of lightweight design and various constraints *** displacement of macrostructure and effective thermal conductivity of microstructure are regarded as the constraint functions, which means taking into account both the loadcarrying capabilities and the thermal insulation *** effective properties of porous material derived from numerical homogenization are used for macrostructural analysis. Meanwhile, displacement vectors of macrostructures from original and adjoint load cases are used for sensitivity analysis of the microstructure. design variables in the form of reciprocal functions of relative densities are introduced and used for linearization of the constraint function. The objective function of total mass is approximately expressed by the second order Taylor series expansion. Then, the proposed concurrent optimization problem is solved using a sequential quadratic programming algorithm, by splitting into a series of sub-problems in the form of the quadratic program. Finally, several numerical examples are presented to validate the effectiveness of the proposed optimization method. The various effects including initial designs, prescribed limits of nodal displacement, and effective thermal conductivity on optimized designs are also investigated. An amount of optimized macrostructures and their corresponding microstructures are achieved.

关键词： concurrent design Topology optimization Homogenization Thermal insulation Nodal displacement Independent continuous mapping method

MATLAB WEB SERVER AND ITS APPLICATION IN REMOTE COLLABORATIVE design OF MAGNETIC BEARING SYSTEMS

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Chinese Journal of Mechanical Engineering 2001年第2期14卷 179-183页

作者： Zhao Aiping Yu Lie Xie Youbai Theory of Lubrication and Bearing Institute,Xi’an Jiaotong University 西安交通大学润滑理论及轴承所陕西西安

Acclimatizing itself to the development of network,Math Works Inc constructed a MATLAB Web Server environment by dint of which one can browse the calculation and plots of MATLAB through Internet *** installation and use of the environment is introduced.A code established on the platform of MATLAB,which deals with the modal analysis of magnetic bearing system(MBS) supporting rotors of five degrees of freedom and considering the coupling of thrust bearing with radical bearings is modified to work in the *** purpose is to realize a remote call of the code by users through Internet for the performance analysis of the *** an application is very important to the concurrent design of MBS and for the utilization of distributive knowledge acquisition resources in collaborative *** work on modification and realization is described and the results are discussed.

关键词： MATLAB Web Server Remote call Magnetic bearing rotor system concurrent design

Research on Maintainability Evaluation Model Based on Fuzzy Theory

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Chinese Journal of Aeronautics 2007年第5期20卷 402-407页

作者：陆中孙有朝南京航空航天大学民航学院江苏南京210016

Maintainability influencing attributes are analyzed, their weight and value calculating methods are given, and the maintainability fuzzy evaluation method is proposed based on the relative closeness. According to the maintenance task simulation operated in virtual environment, the maintainability virtual evaluation model is built by analyzing the maintenance task for each replaceable unit of product. At last, a case study is given based upon the main landing gear system of a certain type civil aircraft, and the result indicates that the model is suitable for maintainability qualitative evaluation and can support maintainability concurrent design.

关键词： maintainability evaluation multiple criteria decision making fuzzy theory virtual maintenance concurrent design

Process Environment Oriented concurrent Tolerance Analysis

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Journal of Beijing Institute of Technology 2001年第2期10卷 157-162页

作者：闫艳宁汝新北京理工大学机械工程与自动化学院北京100081

Tolerance analysis is investigated under an environment of concurrent design in order to lead to optimized tolerance, as traditional tolerance analysis is often inefficient and liable to mistakes. Making full use of knowledge in manufacturing tolerance analysis combined with the beta distribution model is introduced and applied. The use of beta distribution reflects fully actual capabilities in manufacture. concurrent tolerance design is a manufacturing environment oriented design process paying more attention to influences or restraints on product design caused by such factors as the manufacturing process, machine capabilities, economy in manufacturing, etc. Process environment oriented tolerance analysis is more flexible making the designed results more practical and effective.

关键词： concurrent design tolerance analysis beta distribution

concurrent Process Planning for Machined Parts

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Tsinghua Science and Technology 2002年第5期7卷 481-487页

作者：吴丹王先逵李志忠 Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China

Detailed manufacturing information about the parts can help designers produce better designs. Detailed manufacturing information is conveyed to the designer through micro-circles within the concurrent design process for machined parts, focusing on instantaneous product design and process planning. The process has three key elements: a hierarchical architecture design of the concurrent process planning system, modeling and reengineering of the concurrent process planning, and modeling of information. The approach is successfully implemented and applied for concurrent design and process planning of some complicated parts.

关键词： concurrent engineering concurrent design process planning