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Mesh theory of angle modified dual tori double-enveloping toroidal worm drive

Science china(Technological Sciences) 2010年第7期53卷 1913-1927页

作者： ZHAO YaPing1, SU DaiZhong2, ZHANG Zhao1, WEI WenJun3.& DONG XueZhu3.1 college of Machinery and Automation, wuhan university of Science and {3., wuhan 43.081, china 2 Advanced Design and Manufacturing engineering Center, Nottingham Trent university, Nottingham NG1 4BU, UK 3.college of engineering, china Agricultural university, Beijing 100083. china 1. college of Machinery and Automation Wuhan University of Science and Technology Wuhan 430081 China2. Advanced Design and Manufacturing Engineering Center Nottingham Trent University Nottingham NG1 4BU UK3. College of Engineering China Agricultural University Beijing 100083 China

In this paper, the meshing theory of the angle modified hourglass worm drive is enriched and developed. The ordinary condition of the angle modification is derived and the physical significance of the modification is interpreted. A normal section methodology is proposed for meshing analysis, which can be used to compute the normal distance near a singular meshing point of a conjugate surface couple. By means of the method and after analyzing the normal transversals, it is specified that the worm helicoid, the nominal former contact zone and the new contact zone intersect each other along the locus of singular points of the instantaneous contact lines of an angle-modified worm pair. As a result, it is explained clearly that those three osculate each other but the osculations are different in degree. Moreover, the mechanism of removing the twice-contacted zone from the worm gear tooth surface is clarified and the reason of shortening the worm working length is also elucidated. With the help of the theory described in the present paper and the thorough and systematic research on the relevant meshing characteristics, the angle modified dual tori double-enveloping toroidal worm drive has been shown to be an excellent new-fashioned hourglass worm set.

关键词： hourglass worm angle modification double-enveloping osculation normal transversal

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Microwave Irradiation Treatment of Wood Flour and Its Application in PVC-Wood Flour Composites

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Journal of wuhan university of technology(Materials Science) 2007年第1期22卷 148-152页

作者：胡圣飞陈文 Institute of Materials Science and engineering Wuhan University of Technology School of Chemical and Environmental engineering Hubei University of Technology Wuhan 430068China

The technique of microwave irradiation induced free radical bulk- polyaddition reactions in porous wood flour was used to modify wood flour. The behaviors of the modified wood flour under microwave irradiation, such as thermal stability and moisture sorption properties, were studied. A kind of semiinterpenetrating polymer network wood four （Semi-IPN-WF） can be formed through polymerization of MMA in the porous wood flour by microwave irradiation, and the thermal decomposition temperature of the semi-IPN-WF is considerably increased. PVC/Semi-IPN-WF composites were prepared by melt mixing in double rolls, which exhibit improved rheological properties, lower water sorption properties and outstanding mechanical performances.

关键词： microwave irradiation wood flour poly(vinyl chloride) composites

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A New Genetic Algorithm Based on Niche Technique and Local Search Method

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Journal of university of Science and technology Beijing 2001年第1期8卷 63-68页

作者： Jinwu Xu, Jiwen Liu mechanical engineering School, university of Science and {3. Beijing, Beijing 100083. china Univ Sci & Technol Beijing Sch Mech Engn Beijing 100083 Peoples R China

The genetic algorithm has been widely used in many fields as an easy robust global search and optimization method. In this paper, a new generic algorithm based on niche technique and local search method is presented under the consideration of inadequacies of the simple genetic algorithm. In order to prove the adaptability and validity of the improved genetic algorithm, optimization problems of multimodal functions with equal peaks, unequal peaks and complicated peak distribution are discussed. The simulation results show that compared to other niching methods, this improved genetic algorithm has obvious potential on many respects, such as convergence speed, solution accuracy, ability of global optimization, etc.

关键词： genetic algorithm (GA) niche technique local search method

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INVESTIGATION ON DEPOSITIONS AND HARDNESS CHARACTERISTICS OF a-SiC:H FILMS

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 761-764页

作者： X.F.Rong and Z.Y.Qin college of mechanical engineering,Taiyuan {3. of technology, Taiyuan 03.024, china Taiyuan Univ of technology Taiyuan China

In this paper, a deposition feature of a SiC:H films deposited by a RF sputtering system and a effect on the hardness of the films with various deposition conditions are investigated, and the effects of the silicon on a C:H are studied. It follows from the results that the properties of hardness can be changed with the depositing conditions. An increase of silane in the gas phase allows to deposit a SiC:H having tetrahedral structure. The sets of deposition conditions by which the different types of a SiC:H films can be deposited are obtained.

关键词： a SiC:H film sputtering hardness

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Interactions of particles with solidifying front in Al_2O_(3.) /Al Si composites

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中国有色金属学会会刊：英文版 1999年第3期9卷 524-529页

作者： Wu Shusen(吴树森), Huang Naiyu(黄乃瑜),An Ping(安萍) college of Materials Science and engineering, Huazhong university of Science and {3., wuhan 43.074, P.R. china Huazhong Univ Sci & Technol Coll Mat Sci & Engn Wuhan 430074 Peoples R China

The behavior of ceramic particles at the solid/liquid interface and the distribution of particles in metallic matrix composites was studied with a zone unidirectional solidification method. Two kinds of partice dispersed composites, Al 2O 3. /Al 12.6%Si Sr and Al 2O 3. /Al 12.6%Si Sr Ca containing Al 2O 3.particles in volume fraction 2%～5% were used. In the Al 2O 3. /Al Si Sr composites, the particles were pushed by the solidifying front, and did not uniformly distribute in the solid. But in the Al 2O 3. /Al Si Sr Ca composites, the particles were engulfed by the solidifying front and uniformly distributed in the solid. The particles engulfing into the solid was realized only by Sr and Ca addition at the same time. As the interfacial energy between solid and particle was decreased in this case, the Al 2O 3.particles acted as the substrates of heterogeneous nucleation for the Si phases, which made the particles to be engulfed.

关键词： metallic matrix composites solidification particle size distributionDocument code: A

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CLASSIFICATION OF GEAR FAULTS USING HIGHER-ORDER STATISTICS AND SUPPORT VECTOR MACHINES

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Chinese Journal of mechanical engineering 2002年第3期15卷 243-247页

作者： Lai Wuxing Zhang Guicai Shi Tielin Yang ShuziSchool of mechanical Science and engineering, Huazhong university of Science and {3.,wuhan 43.074, china *** School of mechanical Science and engineering Huazhong University of Science and Technology Wuhan 430074 China

Gears alternately mesh and detach in driving process, and then workingconditions of gears are alternately changing, so they are easy to be spalled and worn. But becauseof the effect of additive gaussian measurement noises, the signal-to-noises ratio is low; theirfault features are difficult to extract. This study aims to propose an approach of gear faultsclassification, using the cumulants and support vector machines. The cumulants can eliminate theadditive gaussian noises, boost the signal-to-noises ratio. Generalisation of support vectormachines as classifier, which is employed structural risk minimisation principle, is superior tothat of conventional neural networks, which is employed traditional empirical risk minimisationprinciple. Support vector machines as the classifier, and the third and fourth order cumulants asinput, gears faults are successfully recognized. The experimental results show that the method offault classification combining cumulants with support vector machines is very effective.

关键词： Support vector machine Gear Fault diagnosis Cumulant Featureextraction

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New concept and new theory of mobility calculation for multi-loop mechanisms

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Science china(Technological Sciences) 2010年第6期53卷 1598-1604页

作者： ZHANG YiTong & MU DeJun mechanical engineering college of Yanshan {3.,Qinhuangdao 066004,china 1. mechanical engineering college of Yanshan {3. Qinhuangdao 066004 China

In 2005,Gogu,a Frenchman,analyzed 3. different existing formulas for mobility calculation and pointed that the formulas for quick mobility calculation had some limitations and were not ***,looking for a general and simple mobility formula is still a hot topic in *** the meantime,it is also an important topic to complete the mechanism *** proposed a new method that can avoid determining virtual constraints in 2008,but the method is still not *** solve the problem,this paper defines the new concepts of link-group rank,general-kinematic-pair rank,virtual pair,virtual loop,and virtual-loop rank,and gives a new simple and general *** method converts multi-loop mechanisms into some independent virtual loops,simplifies the problem,avoids calculating virtual constraints,and reduces the calculation *** is proved that the new formula is simple,general and effective through the mobility analysis of several different kinds of *** application of this formula will provide great convenience for general engineers in mobility calculation.

关键词： multi-loop mechanism mobility general kinematic pair virtual loop

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ARCHITECTURE OF MANUFACTURING EXECUTION SYSTEM IN THE EXTENDED ENTERPRISE

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Chinese Journal of mechanical engineering 2002年第1期15卷 90-93页

作者： Song Haisheng college of Electronic and mechanical engineering， Hebei {3. of Science and technology，Shijiazhuang 050054，china Wang Jiahai Zhang Shu Tongji {3. college of Electronic and mechanical engineering Hebei University of Science and Technology Shijiazhuang 050054 China

The extended enterprise is formed according to the philosophy of dispersednetworked manufacturing. Manufacturing execution system (MES) can close the information gap whichexists between device control system and production information management system. The functions andthe web-based architecture of the MES in the extended enterprise are introduced. Using thecooperating system models of object-oriented and distributed agents and CORBA, all objects keep touniform interface standards and are easily inserted to object request broker. The utilization ofdistributed MES in extended enterprise can adapt fast change of manufacturing environment andresource. It also can improve the independent management capability of manufacturing cell and theenterprise response capability to global economic competition.

关键词： Extended enterprise Manufacturing execution system Dispersed networkedmanufacturing Agent

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EXTRAPOLATING METHOD IN PLOT FOR FATIGUE LIFE PREDICTION OF COMPONENTS

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中国有色金属学会会刊：英文版 1996年第3期6卷 153-156页

作者： Liu Yilun Wang Ailun(college of mechanical and Electrical engineering,Central South {3. of technology, Changsha 410083. CENT S UNIV TECHNOL COLL MECH & ELECT ENGNCHANGSHA 410083PEOPLES R CHINA

ＥＸＴＲＡＰＯＬＡＴＩＮＧＭＥＴＨＯＤＩＮＰＬＯＴＦＯＲＦＡＴＩＧＵＥＬＩＦＥＰＲＥＤＩＣＴＩＯＮＯＦＣＯＭＰＯＮＥＮＴＳ￥ＬｉｕＹｉｌｕｎ；ＷａｎｇＡｉｌｕｎ（ＣｏｌｌｅｇｅｏｆＭｅｃｈａｎｉｃａｌａｎｄＥｌｅｃｔ... 详细信息

ＥＸＴＲＡＰＯＬＡＴＩＮＧＭＥＴＨＯＤＩＮＰＬＯＴＦＯＲＦＡＴＩＧＵＥＬＩＦＥＰＲＥＤＩＣＴＩＯＮＯＦＣＯＭＰＯＮＥＮＴＳ￥ＬｉｕＹｉｌｕｎ；ＷａｎｇＡｉｌｕｎ（ＣｏｌｌｅｇｅｏｆＭｅｃｈａｎｉｃａｌａｎｄＥｌｅｃｔｒｉｃａｌＥｎｇｉｎｅｅｒｉｎｇ，...

关键词： extrapolation plot fatigue life

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Digital close-range photogrammetric application to small-scale physical simulation experiment

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中国有色金属学会会刊：英文版 2011年第S3期21卷 681-685页

作者： LI Chun-yi1, CUI Xi-min2, YU Yi-ju3.1. School of Surveying and Landing Information engineering, Henan Polytechnic university, Jiaozuo 454003. china 2. {3. of Geoscience and Surveying engineering, china university of Mining and technology, Beijing 100083. china 3. Surveying and Mapping Press, Beijing 100045, china [a] School of Surveying and Landing Information engineering Henan Polytechnic University Jiaozuo 454003 China [b] college of Geoscience and Surveying engineering China University of Mining and Technology Beijing 100083 China [c] Surveying and Mapping Press Beijing 100045 China

In order to research the possibility of digital close-range photogrammetric surveying in small scale physical simulation experiment, physical model coinciding with engineering practice was constructed based on similar theory. The datum processing method and surveying precision of digital close-range photogrammetric were analyzed. And the function relationship between overburden subsidence factor qr and the ratio z/H of stratum horizon z and mining depth H was researched. The results show that surveying points position mean error along horizontal direction is ±0.13. mm and vertical direction is ±0.192 mm. Therefore, multi-taking station cross direction digital close-range photogrammetric can completely satisfy the precision need of physical simulation experiment. And the empirical formula can be utilized to represent evolution law of stratum subsidence factor.

关键词： close-range photogrammetric physical simulation light-rays adjustment surveying precision subsidence factor

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