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A reliability assessment method based on support vector machines for CNC equipment

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Science China(Technological Sciences) 2009年第7期52卷 1849-1857页

作者： WU Jun DENG Chao SHAO XinYu xie S q School of Naval Architecture and Ocean Engineering Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Digital Manufacturing Equipment&Technology Huazhong University of Science and TechnologyWuhan 430074China Department of Mechanical Engineering University of AucklandAucklandNew Zealand

With the applications of high technology,a catastrophic failure of CNC equipment rarely occurs at normal operation *** it is difficult for traditional reliability assessment methods based on time-to-failure distributions to deduce the reliability *** paper presents a novel reliability assessment methodology to estimate the reliability level of equipment with machining performance degradation data when only a few samples are *** least squares support vector machines(LS-SVM) are introduced to analyze the performance degradation process on the equipment.A two-stage parameter optimization and searching method is proposed to improve the LS-SVM regression performance and a reliability assessment model based on the LS-SVM is built.A machining performance degradation experiment has been carried out on an OTM650 machine tool to validate the effectiveness of the proposed reliability assessment methodology.

关键词： reliability assessment least squares support vector machines performance degradation radial basis function parameter optimization

A compliant surgical robotic instrument with integrated IPMC sensing and actuation

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International Journal of Smart and Nano Materials 2012年第3期3卷 188-203页

作者： A.J.McDaid S.q.xie K.C.Aw Mechanical Engineering Department University of AucklandAuckland 1142New Zealand

Robotic assisted surgery is becoming widely adopted by surgeons for a number of reasons,which include improved instrumentation control and dexterity as well as faster patient recovery times and cosmetic *** assisted surgery is currently one of the fastest growing applications in *** the traditional robotic actuators which are currently used have advanced performance which can,in some aspects,surpass that of humans,they simply do not have the capabilities and diversity required to meet the demand for new applications in robotic *** transducers which have advanced capabilities and which allow safe operation in delicate environments are *** polymer-metal composites(IPMCs)have extensive desirable characteristics when compared with traditional actuators and as their transduction mechanisms can mimic biological muscle they have much potential for future advanced biomedical and surgical *** this research,a complete two degree-of-freedom(2DOF)surgical robotic instrument has been developed,which with the attachment of surgical tools(scalpel,etc.)has the ability to undertake surgical *** system integrates an IPMC sensor and actuator at each joint.A gain scheduled(GS)controller,which is tuned with an iterative feedback tuning(IFT)algorithm,has been developed to ensure an accurate and adaptive *** main advantages of this device over traditional devices are the improved safety through a natural compliance of the joints as well as the mechanical simplicity which ensures ease of miniaturisation for minimally invasive surgery(MIS).The components of the system have been tested and shown to have the capabilities required to operate the device for certain surgical procedures,specifically a device work envelope of 1600 mm^(2),compliance of 0.0668 m/N while still maintaining enough force to cut tissue,IPMC sensor accuracy between 3-22%and a control system which has shown to guarantee zero steady state error.

关键词： ionic polymer-metal composite surgical robotics iterative feedback tuning

LOW TEMPERATURE THERMODYNAMIC STUDY OF THE STABLE AND METASTABLE PHASES OF SILVER

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Acta Metallurgica Sinica(English Letters) 2007年第5期20卷 355-362页

作者： X.B. Li Y.q. xie Y.Z. Nie H.J. Peng Research Center of Advanced Materials Xiangtan University Xiangtan 411105 China School of Material Science and Engineering University Changsha 410083 China Central South

The low temperature thermodynamics of the stable phase of silver was assessed by the polynomial model and Debye model from the experimental data available in the literature. By means of the constrained non-linear least squares curve fitting arithmetic, two sets of parameter values were determined. The expression of the thermodynamic functions cp（T） and G（T）-H （298.15K） at 0-298.15K were presented. Only the low temperature thermodynamics of the metastable phase of silver can be extrapolated by the Debye model The expression of the thermodynamic functions cp（T） at 0- 298.15K was presented.

关键词： silver thermodynamic heat capacity SGTE (Scientific Group Thermodata Europe)

STABILITY OF MICROSTRUCTURES DURING COOLING PROCESSES OF Al LIqUID METAL

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中国有色金属学会会刊：英文版 1998年第4期8卷 2-7页

作者： Liu, RS Li, JY Zhou, Z Dong, KJ Peng, P xie, q Zheng, CX Hunan Univ Dept Phys Changsha 410012 Peoples R China Hunan Univ Dept Chem Changsha 410012 Peoples R China

１ＩＮＴＲＯＤＵＣＴＩＯＮＩｔｉｓｗｅｌｋｎｏｗｎｔｈａｔｔｈｅｍａｃｒｏｓｃｏｐｉｃｐｒｏｐｅｒｔｉｅｓｏｆｍｅｔａｌｓａｎｄａｌｏｙｓａｒｅｍａｉｎｌｙｄｅｔｅｒｍｉｎｅｄｂｙｔｈｅｉｒｍｉｃｒｏｓｔｒｕｃｔｕ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＩｔｉｓｗｅｌｋｎｏｗｎｔｈａｔｔｈｅｍａｃｒｏｓｃｏｐｉｃｐｒｏｐｅｒｔｉｅｓｏｆｍｅｔａｌｓａｎｄａｌｏｙｓａｒｅｍａｉｎｌｙｄｅｔｅｒｍｉｎｅｄｂｙｔｈｅｉｒｍｉｃｒｏｓｔｒｕｃｔｕｒｅｓ，ａｎｄｔｈｅｍｉｃｒｏｓｔ...

关键词： stability microstructure liquid metal rapid cooling computer simulation

Dioxin induces expression of hsa-mi R-146b-5p in human neuroblastoma cells

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Journal of Environmental Sciences 2018年第1期30卷 260-267页

作者： Tuan Xu Heidi q.xie Yunping Li Yingjie Xia Rui Sha Lingyun Wang Yangsheng Chen Li Xu Bin Zhao State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Dioxin can cause a series of neural toxicological effects. Micro RNAs（mi Rs） play important roles in regulating nervous system function and mediating cellular responses to environmental pollutants, such as dioxin. Hsa-mi R-146 b-5 p appears to be involved in neurodegenerative diseases and brain tumors. However, little is known about effects of dioxin on the expression of hsa-mi R-146 b-5 p. We found that the hsa-mi R-146 b-5 p expression and its promoter activity were significantly increased in dioxin treated SK-N-SH cells, a human-derived neuroblastoma cell line. Potential roles of hsa-mi R-146 b-5 p in mediating neural toxicological effects of dioxin may be due to the regulation of certain target genes. We further confirmed that hsa-mi R-146 b-5 p significantly suppressed acetylcholinesterase（ACh E） activity and targeted the3′-untranslated region of the ACh E T subunit, which has been down-regulated in dioxin treated SK-N-SH cells. Functional bioinformatic analysis showed that the known and predicted target genes of hsa-mi R-146 b-5 p were involved in some brain functions or cyto-toxicities related to known dioxin effects, including synapse transmission, in which ACh E may serve as a responsive gene for mediating the effect.

关键词： 2 3 7 8-Tetrachlorodibenzo-p-dioxin(TCDD) MicroRNA Acetylcholinesterase(AChE) Neuron Transcription regulation Post-transcriptional regulation

Development of an ionic polymer-metal composite stepper motor using a novel actuator model

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International Journal of Smart and Nano Materials 2010年第4期1卷 261-277页

作者： A.J.McDaid K.C.Aw K.Patel S.q.xie E.Haemmerle Department of Mechanical Engineering The University of AucklandNew Zealand

A novel ionic polymer–metal composite(IPMC)actuated stepper motor was developed in order to demonstrate an innovative design process for complete IPMC *** motor was developed by utilizing a novel model for IPMC actuators integrated with the complete mechanical model of the *** dynamic,nonlinear IPMC model can accurately predict the displacement and force actuation in air for a large range of input voltages as well as accounting for interactions with mechanical systems and external *** integrating this geometrically scalable IPMC model with a mechanical model of the motor mechanism an appropriate size IPMC strip has been chosen to achieve the required motor *** entire integrated system has been simulated and its performance *** system has been built and the experimental results validated to show that the motor works as simulated and can indeed achieve continuous 360rotation,similar to conventional *** has proven that the model is an indispensable design tool for integrated IPMC actuators into real *** newly developed system has demonstrated the complete design process for smart material actuator systems,representing a large step forward and aiding in the progression of IPMCs towards wide acceptance as replacements for traditional actuators.

关键词： ionic polymer-metal composite(IPMC) stepper motor mechanical design model application

GROWTH OF β-SiC BY rf SPUTTERING ON SILICON SUBSTRATES

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Acta Metallurgica Sinica(English Letters) 2002年第2期15卷 210-214页

作者： S.Liu. E. q. xie, q. Wen, Z. W. Ma and C. C. Ning Department of Physics, Lanzhou University, Lanzhou 730000, China Department of Physics Lanzhou University Lanzhou 730000 China

Rf sputtering in an Ar discharge of a SiC target has been used to deposit β-SiCfilms on Si-(111) substrates. XRD and infrared absorption spectra measurementswere used to characterize the films. The results show that the deposited films are(111)-oriented β-SiC films, and a C rich buffer layer formed between the substrateand SiC films when the substrate temperature is higher than 800℃. IR and XRDresults of an annealing process at 800℃ in H2 atmosphere, indicate that the crystallinequality is determined mainly by the substrate temperature during the film growth, andthe annealing process can improve the quality of Si/SiC interface. Higher substratetemperature leads to better quality of crystalline structttre and lower quality of SiC/Siinterfaces. Combined with an annealing process we obtained SiC films with very goodquality of both crystalline and SiC /Si interface.

关键词： SiC. sputtering. IR. XRD

A STUDY OF TEMPERATURE-DEPENDENT VALENCE BOND STRUCTURE OF TITANIUM

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Acta Metallurgica Sinica(English Letters) 2007年第1期20卷 27-34页

作者： X.B. Li Y.q. xie Y.Z. Nie H.J. Peng H.J. Tao F.X. Yu College of Materials Science and Engineering Central South University Changsha 410083 China

On the basis of energy and shape method for the determination of the valence bond （ VB ） structures of crystal, the valence bond structure of titanium is redetermined at room temperature and calculated in the whole temperature range of 0-1943K. The outer shell electronic distribution of Ti is ec^29907. （sc^0.4980 ＋ dc^2.4927） ef^1.0098 in crystal. The temperature dependences of the VB structures of hcp and bcc phases are the same. The VB structures of hcp and bcc phases monotonically increase or decrease with the increase in temperature, but show discontinuous changes at the phase-transformation temperature 1155K.

关键词： valence bond structure temperature titanium

FORMATION OF MANGANESE SILICIDE THIN FILMS BY SOLID PHASE REACTION

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Acta Metallurgica Sinica(English Letters) 2002年第2期15卷 221-226页

作者： E. q. xie, W. W. Wang, N. Jiang and D. Y. He Department of Physics, Lanzhou University, Lanzhou 730000, China Department of Physics Lanzhou University Lanzhou 730000 China

Manganese silicide MnSi_(2-x) thin films have been prepared on n-type siliconsubstrates through solid phase reaction. The heterostructures were analyzed by X-ray diffraction,Rutherford backscattering spectroscopy, Fourier transform infrared transmittance spectroscopy andthe four-point probe technique. The results show that two manganese silicides have been formedsequentially via the reaction of thin layer Mn with Si substrate at different irradiation annealingstages, i.e., MnSi at 450 deg C and MnSi_(1.73) at 550 deg C. MnSi_(1.73) phase exhibits preferredgrowth after irradiation with infrared. In situ four-point probe measurements of sheet resistanceduring infrared irradiation annealing show that nucleation of MnSi and phase transformation of MnSito MaSi_(1.73) occur at 410 deg C and 530 deg C, respectively; the MnSi phase shows metallicbehavior, while MnSi_(1.73) exhibits semiconducting behavior. Characteristic phonon bands ofMnSi_(2-x) silicides, which can be used for phase identification along with conventional XRDtechniques, have been observed by FTIR spectroscopy.

关键词： manganese silicide in situ sheet resistance solid phase reaction infrared spectra