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Optimal Process Design of Shrinkage and Sink Marks in Injection Molding

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Journal of Wuhan university of technology(Materials Science) 2007年第3期22卷 404-407页

作者：张志莲 school of mechanical and electrical engineering Beijing University of Chemical Technology

The optimal process conditions of an injection molded polypropylenes dustpan were investigated to improve the part quality. A fractional factorial experiment was employed to screen the significant factors and main combinations among the numerous process parameters. And, with the consideration of interaction effects, an L27 orthogonal array based on the Taguchi method was conducted to determine the optimal process conditions. The results indicate that the melt temperature has the most remarkable influence on both the volume shrinkage and sink marks criterion weights. But the optimal process conditions and the order of influence are different for the two criterion weights.

关键词： optimal fractional interaction

Research on Parametric Process Planning technology Based on Three-dimensional Part Model

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武汉理工大学学报 2006年第S2期28卷 502-506页

作者： DING Yufeng WEI Zhongling (school of mechanical and electrical engineering,Wuhan university of technology,Wnhan 430070,china school of mechanical and electrical engineering Wuhan University of TechnologyWuhan 430070China

CAPP(Computer Aided Process Planning) has already become the bottleneck of CAD/CAM *** two- dimensional CAPP system which is used in the enterprise needs to be input information and data again,because it can not draw data from CAD(Computer Aided Design) model automatically after building CAD model and *** has influenced extensive use of CAPP system because of its low *** this paper,three-dimensional model is built by using the parametric method, the process file cart be produced directly through drawing corresponding characteristic and parameter from the model with the aid of process *** improves the efficiency of product *** C++6.0 and SQL Server 2000 are used to devel- op WTJDCAPP prototype system based on component model and SolidWorks three-dimensional CAD *** valve-seat is taken as concrete object to validate of the technology.

关键词： solidworks CAPP process planning valve-seat

Design of Fault Tolerant Wireless Networked Control Systems

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Design of Fault Tolerant Wireless Networked Control Systems

Control strategy of disc braking systems for downward belt conveyors

2011 Chinese Control and Decision Conference（CCDC）

作者： Wei Li is with the school of mechanical and electrical engineering,china university of mining and technology,xuzhou,221116,china. Zhongqiu Wang is with the school of mechanical and electrical engineering,china university of mining and technology,xuzhou,221116,china. Gongbo Zhou is with the school of mechanical and electrical engineering,china university of mining and technology,xuzhou,221116,china. Zhencai Zhu is with the school of mechanical and electrical engineering,china university of mining and technology,xuzhou,221116,china.

In this paper the design of fault tolerant wireless networked control systems （WNCS） is *** considered architecture of WNCS consists of a local execution layer,a supervision layer and a resource management layer,which are connected with wireless communication *** an architecture is often used in industrial *** approach of integrated design of those layers as well as the communication channel,is *** major objective is to improve system robustness against system and network disturbances （packet loss,bit error）,and tolerance to equipment and network faults.A communication protocol is also designed to meet those requirements.

关键词： Fault Detection Fault Tolerant Control Wireless Networked Control Systems Communication Protocol

来源： cnki会议评论

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mining Science and technology 2011年第4期21卷 491-494页

作者： hou youfu xie fangwei Huang Fei school of mechanical and electrical engineering China University of Mining ＆ Technology Xuzhou 221008 China school of mechanical engineering Jiangsu University Zhenjiang 212013 China

Reliability of braking systems is a key requirement to ensure the safety of in using downward belt conveyor brakes. By analyzing and comparing three commonly used braking velocity curves, we conclude that the Harrison curve is the best. Given the characteristics of a downward belt conveyor, we studied the control in a closed-loop velocity, a conventional PID method and an optimal PID control method. We used MATLAB/Simulink to simulate the three control methods. Our simulation results show that opti- mal PID control is especially suitable for disc braking systems. To verif!/the results from theoretical anal- ysis and simulation, a multifunctional test-bed was developed to simulate the braking process of a disc brake system. Our experimental results demonstrate that the optimal PID control can make the output velocity to follow a preset velocity correctly with only small fluctuations, meeting the requirements of a flexible brake for a belt conveyor.

关键词： Downward belt conveyorDisc braking systemHarrison velocity curve Optimal PIDControl strategy

Aging assessment of large generator insulation based on PD measurements

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Progress in Natural Science:Materials International 2005年第11期15卷 1035-1043页

作者： YUE Bo, CHEN Xiaolin, CHENG Yonghong and xie Hengkun (State Key Laboratory of electrical Insulation and Power Equipment, Xi'an Jiaotong university, Xi'an 710049, china Graduate school at Shenzhen, Tsinghua university, Shenzhen 518055, china Department of electrical engineering, Tsinghua university, Beijing 100084, china) State Key Laboratory of electrical Insulation and Power Equipment Xi''an Jiaotong University Xi''an 710049 China. Graduate school Shenzhen Tsinghua University Shenzhen 518055 China. Department of electrical engineering Tsinghua University Beijing 100084 China

The statistical parameters of phase resolved partial discharge (PD) distribution and ultra-wideband (UWB) characteristics of PD pulse are proposed for aging assessment of large generator insulation. Multi-stress aging tests of the model generator stator bar specimens were performed and PD measurements were conducted using both digital PD detector with frequency ranging from 40 kHz to 400 kHz and UWB PD detector with bandwidth from 10 MHz to 3 GHz at different aging stages. The test results show that the skewness and UWB frequency characteristics of PD can be taken as the characterization parameters for aging assessment of generator insulation. Furthermore, the measurement results of real generator stator bars show that these methods based on statistical parameters and UWB characteristics of PD are prospective for aging assessment and residual lifetime estimation of large generator stator insulation.

关键词： partial discharge stator insulation multi-stress accelerated aging statistical parameters ultra-wideband aging assessment.

Digital Kilns and Furnaces——the Development Direction of Industrial Kilns and Furnaces in the 21st Century

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同方期刊数据库

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武汉理工大学学报 2006年第S1期28卷 260-264页

作者： WANG Xiaoming,HUANG Zhichu,ZHANG Jiafan (school of mechanical and electrical engineering,Wuhan university of technology, Wuhan 430070,china) school of mechanical and electrical engineering Wuhan University of TechnologyWuhan 430070China

The digital manufacturing theory is applied to the special manufacturing equipments——industrial kilns and furnaces; the concept of digital kilns & furnaces is put forward. The present status of research and application for digital technologies in fuel industrial kilns & furnaces is also introduced. Then,take the case of gas fuel kilns & furnaces,their main key technical issues are discussed. Digital kilns & furnaces as an important constituent of the digital equipments are the crucial base of the digital manufacturing. The value of research on digital kilns & furnaces and the application prospect are undoubted. It will improve product quality,reduce the manpower cost,enhance product market competitive ability,promote comprehensively tradition industries such as ceramics,metallurgy industry,and so on.

关键词： digital manufacturing digital equipment digital kilns and furnaces digital technologies

Microstructure and mechanical Properties of High-Cr Cast Iron Bars Reinforced Hadfield Steel Matrix Composites

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Journal of Wuhan university of technology(Materials Science) 2010年第3期25卷 464-468页

作者：牛立斌 Institute of Wear-Resistance Materials School of Mechanical and Electrical EngineeringXi'an University of Architecture and Technology

To obtain the compatible material of high hardness and high toughness,Hadfield steel matrix composites,reinforced by high-Cr cast iron bars made of flux-cored welding wires,which were inserted into the Hadfield steel melt,were *** mechanical properties of three materials,i e,composites for as-cast and quenching-water condition,as well as Hadfield steel,were *** results show that the alloy powder inside flux-cored welding wires can be melted by the heat capacity of Hadfield steel melt and solidify into high-Cr cast iron *** impact toughness of the composite for quenching-water condition is higher than that of the composite for as-cast condition and is lower than that of the Hadfield steel,but it can still meet the requirements of hardness and toughness in industrial *** of load variation,composite for quenching-water condition shows better wear resistance than those of the composite for as-cast condition and Hadfield *** modified fracture toughness and wear resistance of composites are attributed to not only the combining actions of Hadfield steel matrix and high-Cr cast iron bars,but also the effect of heat treatment.

关键词： composites flux-cored welding wires impact toughness hadfield steel

Novelty Detection Methods and Novel Fault Class Detection

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武汉理工大学学报 2006年第S2期28卷 767-771页

作者： ZHANG Jiafan HUANG Zhichu WANG Xiaoming (school of mechanical and electrical engineering,Wuhan university of technology,Wuhan 430070,china, school of mechanical and electrical engineering Wuhan University of TechnologyWuhan 430070China

The ability to detect a new fault class can be a useful feature for an intelligent fault classification and diagnosis *** adopt two novelty detection methods,the support vector data description (SVDD) and the Parzen density estimation, to represent known fault class samples,and to detect new fault class *** experiments on real multi-class bearing fault data show that the SVDD can give both high novelty detection rate and target recognition rate,respectively for the prescribed’ un- known’ fault samples and the known fault samples by choosing the appropriate SVDD algorithm parameters;but the Parzen densi- ty estimation only give a better novelty detection rate in our experiments.

关键词： novelty detection support vector data description(SVDD) parzen density estimation fault diagnosis

Strengthening and toughening styrene-butadiene rubber by mechanically interlocked cross-links

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Science china Chemistry 2024年第10期67卷 3414-3422页

作者： Yuanhao Wang Li Yang Lin Cheng Jun Zhao Ruixue Bai Wenbin Wang Shaolei Qu Zhaoming Zhang Wei Yu xuzhou Yan school of Chemistry and Chemical engineering Frontiers Science Center for Transformative MoleculesShanghai Key Laboratory of Electrical Insulation and Thermal AgingShanghai Jiao Tong UniversityShanghai 200240China

Styrene-butadiene rubber(SBR)is an indispensable material in modern society,and the necessity for enhanced mechanical properties in SBR persists,particularly to withstand the rigors of challenging environmental *** surmount the limitations of conventional cross-linking modes,mechanical bonds stabilized by host-guest recognition are incorporated as the cross-linking points of SBR to form mechanically interlocked networks(MINs).Compared with covalently cross-linked network,the representative MIN exhibits superior mechanical performance in terms of elongation(1392%)and breaking strength(4.6 MPa),whose toughness has surged by 17 *** of host-guest recognition and subsequent sliding motion provide an effective energy dissipation mechanism,and the release of hidden length is also beneficial to enhance ***,the introduction of the rotaxane cross-links made the network more pliable and possess damping and elastic properties,which can return to initial state with one minute rest *** aspire that this direct introduction method can serve as a blueprint,offering valuable insights for the enhancement of mechanical properties in conventional commercial polymer materials.

关键词： mechanically interlocked molecules host-guest chemistry styrene-butadiene rubber mechanical properties dynamic materials