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Four Methods for Roundness Evaluation

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Four Methods for Roundness Evaluation

A Modified T-test Feature Selection Method and Its Application on the HapMap Genotype Data

2010 4th International Conference on Intelligent Information Technology Application (IITA2010)

作者： Wentao Sui school of Mechanical engineering shandong university of Technology Zibo china Dan Zhang school of electrical & electronic engineering shandong university of Technology Zibo china

Whether roundness error can be evaluated accurately and efficiently or not will directly influence the mechanical products performance and *** this reason,this paper introduces simple and efficient algorithms to evaluate the roundness error from the measured points using four internationally defined methods:Least Squares Circle（LSC）,Minimum Circumscribed Circle（MCC）,Maximum Inscribed Circle（MIC） and Minimum Zone Circles（MZC）.A software has been developed using Matlab to apply these algorithms on the test data.

关键词： Roundness error Optimization Minimum zone circle Minimum circumscribed circle Maximum inscribed circle

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Genomics,Proteomics & Bioinformatics 2007年第Z1期 242-249页

作者： Nina Zhou and Lipo Wang school of electrical and electronic engineering,Nanyang Technological university,Singapore.

Single nucleotide polymorphisms (SNPs) are genetic variations that determine the differences between any two unrelated individuals. Various population groups can be distinguished from each other using SNPs. For instance,the HapMap dataset has four population groups with about ten million SNPs. For more insights on human evolution,ethnic variation,and population assignment,we propose to find out which SNPs are significant in determining the population groups and then to classify different populations using these relevant SNPs as input features. In this study,we developed a modified t-test ranking measure and applied it to the HapMap genotype data. Firstly,we rank all SNPs in comparison with other feature importance measures including F-statistics and the informativeness for assignment. Secondly,we select different numbers of the most highly ranked SNPs as the input to a classifier,such as the support vector machine,so as to find the best feature subset corresponding to the best classification accuracy. Experimental results showed that the proposed method is very effective in finding SNPs that are significant in determining the population groups,with reduced computational burden and better classification accuracy.

关键词： SNP modified t-test F-statistics SVM

Giant magnetoimpedance effect of multilayered structure(F/SiO_2)_3/Ag/(SiO_2/F)_3 films deposited in a longitudinal magnetic field

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Science china(Technological Sciences) 2010年第3期53卷 287-292页

作者： CHEN WeiPing1,2,SHAO XianYi1,2,FENG ShangShen1,2,XIAO ShuQin3 & LIU YiHua3 1 school of Physics and electronics engineering,Zhejiang Taizhou university,Taizhou 318000,china 2 Institute of Function Materials for electronic Information,Zhejiang Taizhou university,Taizhou 318000,china 3 school of Physics,shandong university,Jinan 250100,china school of Physics and electronics engineering Zhejiang Taizhou University Taizhou China Institute of Function Materials for electronic Information Zhejiang Taizhou University Taizhou China school of Physics Shandong University Jinan China

The soft magnetic properties and giant magnetoimpedance(GMI) effect of the multilayered structure(F/SiO2)3/Ag/(SiO2/F)3(F≡Fe71.5Cu1Cr2.5V4Si12B9) films,which were prepared by radio frequency sputtering without and with a longitudinal magnetic field of about 72 kA/m,are *** results show that the GMI effect almost cannot be detected in the samples deposited without field,whereas,a longitudinal magnetic field applied during deposition process obviously optimizes the soft magnetic properties of the films,and noticeable GMI effect is *** maximum values of the longitudinal and transverse GMI ratios are 45% and 44% at the frequency of 6.81 MHz,*** addition,the dependence of magnetoimpedance ratio,magnetoresistance ratio,magnetoreactance ratio and effective permeability ratio on the frequency has been *** found that the GMI spectrum curves in the longitudinal and transverse cases almost overlap for the field-deposited *** GMI effect is mainly a giant magnetoinductive effect at low *** f >9 MHz,magnetoreactance ratio changes to a negative,i.e.,the property of reactance changes from inductive to capacitive.

关键词： Fe-based soft magnetic alloy as-deposited multilayered films giant magnetoimpedance effect effective permeability magnetic anisotropy

Infrared Spectra of La_(0.65)Ba_xMnO_(3-δ) Oxides

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Rare Metals 2001年第4期20卷 255-258页

作者： Jifan Hu1, Hongwei Qjn 1), Yanming Hao2, Yangxian Li2, Yizhong Wang3), Zhenxi Wan g3) 1) Department of Physics, shandong university, Jinan 250100, china 2) school of electronic engineering and Material Science, Hehei university of Technology. Tianjing 30 山东大学山东济南 250100 河北工业大学天津 300130 中科院物理所北京 100080

The infrared spectra of La_(0.65)Ba_xMnO_(3-|?￡(c) (x = 0.35, 0.33 and 0.30) were investigated experimentally. The result shows that the sample La_(0.65)Ba_xMnO_(3-|?￡(c) has the largest Curie temperature and the smallest resistivity and wave number of the stretching vibration mode of MnO_6 octaheUron at 300 K among the investigated samples. However, the absorption strength for the stretching vibration mode of Mn0_6 octahedron in La_(0.65)Ba_xMnO_(3-|?￡(c) is stronger for parainagnetic phase than that for ferromagnelic phase, which may be connected with the reducing of the dynamic in- coherent Jahn-Teller distortion below Curie temperature. In addition, the large shift of wave number for the stretching mode at the temperatures from 293 to 423 K has been observed in La_(0.65)Ba_xMnO_(3-|?￡(c), which may be due to the in- crease of the Mn-O bond length with temperature increasing.

关键词： infrared spectra colossal magnetoresistance effect perovskite manganite stretching vibration mode Jahn-Teller distortion

electrical property of 8-mol% yttria-stabilized zirconia electrolyte by spark-plasma sintering

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Science china(Technological Sciences) 2004年第5期47卷 569-576页

作者： JIAN Jiawen1,2, CHANG Aimin3, YANG Bangchao2 & ZHANG Yikang4 1. The school of Information Science engineering, Ningbo university, Ningbo 315211, china 2. The school of Microelectronics and Solid-state electronics, university of electronic Science and Tech-nology of china, Chengdu 610054, china 3. The Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830022, china 4. Hongtak (Chengdu) electronic Co., Ltd, Chengdu 610041, china Correspondence should be addressed to Jian Jiawen The school of Information Science engineering Ningbo University Ningbo China The school of Microelectronics and Solid-state electronics University of Electronic Science and Technology of China Chengdu China The Xinjiang Technical Institute of Physics and Chemistry Chinese Academy of Sciences Urumqi China Hongtak (Chengdu) electronic Co. Ltd Chengdu China

Spark-plasma sintering (SPS) process was used to sinter ZrO2 (8Y) powders, and a relative density of 99% has been reached at a low temperature (1350°C) and short dwelling time (10 min) compared to the conventional sintered identical samples (1450°C 4 h)(CS). By the X-ray diffraction (XRD) patterns, the microstructure of the SPS pellet and CS pellet are both indexed by the cubic unit cell (Fm3m). The finer crystallite size (D111) of the SPS pellet is 154 nm and D111 of the CS pellet is more than 1 μm. The AC impedance spectroscopy shows that the ionic conductivity of SPS pellet is different from that of CS pellet. The activation energy for the SPS ceramics, estimated from the slope in the range of 400–800°C, was 91 kJ mol?1, which is in good agreement with CS pellet (96 kJ mol?1), indicating that the conduction mechanism in SPS ceramics is similar to that in CS ceramics.

关键词： yttria-stabilized zirconia electrolyte, spark-plasma sintering, AC impedance.

Study of a novel control method for sensorless brushless DC motor

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Study of a novel control method for sensorless brushless DC ...

Effects of Un-transposed UHV Transmission Line on Fault Analysis of Power Systems

2007'仪表，自动化及先进集成技术大会

作者： Ji Hua Li Zhiyong (school of electrical and electronic engineering,shandong university of Technology,shandong 255091,china)

A novel control method of rotor position detecting for sensorless brushless DC motor based on speed-independent position function is proposed in this *** principle of this method is discussed in *** on the powerful operation function of digital signal processing (DSP),the speed-inde- pendent position function G(O) is determined by analyzing the phase current and phase voltage of permanent magnet brushless DC motor (BLDCM).In order to verify the validity of the proposed control method,the experimental system including hardware and software segments has been developed and the experiments have been *** experimental results demonstrate this control method can detect the rotor posi- tion from near zero speed to high speeds directly without position ***,the experiments al- so indicate that the method can simplify the hardware circuit,generate reliable and precise commutation op- eration and promote the estimation accuracy of rotor position,which proves this control method has favora- ble performance of speed adjustment.

关键词： BLDCM digital signal processor speed-independent position function sensorless

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Transactions of Tianjin university 2008年第3期14卷 231-234页

作者：王安宁陈青周占平 school of electrical engineering Shandong University

The conventional fault analysis method based on symmetrical components supposes that the three-phase parameters of un-transposed transmission line are symmetrical in case of fault. The errors caused by the method with the symmetrical distributed parameter circuit model as the equivalent circuit of the un-transposed ultra high voltage(UHV) transmission line were studied under both normal operation and fault,and the corresponding problems arising were pointed out. By contrast with electromagnetic transient and power electronics(EMTPE) simulation results with the asymmetrical distributed parameter circuit model of un-transposed line, it is shown that the conventional method cannot show the existence of negative and zero sequences before fault happening and there are many errors on voltage and current after fault happening which are different with fault types. The error ranges of voltage and current are 2.13%-81.13% and -7.82%- -86.15%, respectively.

关键词： EMTPE fault calculation simulation un-transposed UHV transmission line

Implementation of Embedded Ethernet Based on Hardware Protocol Stack in Substation Automation System

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Transactions of Tianjin university 2008年第2期14卷 153-156页

作者：马强赵建国刘炳旭 school of electrical engineering Shandong UniversityJinan 250061China

Embedded Ethernet technology has been utilized increasingly widely as the communication mode in the substation automation system(SAS).This paper introduces the current applying situation about embedded Ethernet in SAS *** analyzing the protocol levels used in SAS based on embedded Ethernet and the differences between the TCP and UDP,UDP/IP is selected as the communication protocol between the station-level and bay-level devices for its real-time *** a new kind of implementation of the embedded Ethernet is presented based on hardware protocol *** designed scheme can be implemented easily,reduce cost significantly and shorten developing cycle.

关键词： embedded Ethernet substation automation system hardware protocol stack UDP W3100A

Effect of the Sputtering Parameters on the Structure and Properties of Cu_3N Thin Film Materials

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Journal of Wuhan university of Technology(Materials Science) 2010年第6期25卷 935-937页

作者：钱显毅黄致新 school of electronic Information & Electric engineering Changzhou Institute of Technology College of Physical Science and Technology Cental China Normal University

Copper nitride （Cu3N） thin films were successfully deposited on glass substrates by reactive radio frequency magnetron *** effects of sputtering parameters on the structure and properties of the films were *** experimental results show that with increasing of RF power and nitrogen partial pressure,the preferential crystalline orientation of Cu3N film is changed from （111） to （100）.With increasing of substrate temperature from 70 ℃ to 200 ℃,the film phase is changed from Cu3N phase to *** increasing sputtering power from 80 W to 120 W,the optical energy decreases from 1.85 eV to 1.41 eV while the electrical resistivity increases from 1.45 ×102 Ω·cm to 2.99×103 Ω·cm,respectively.

关键词： copper nitride sputtering parameters structure electrical and optical properties