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| 1 | Moment-independent importance measure of basic random variable and its probability density evolution solution显示文摘To analyze the effect of basic variable on failure probability in reliability analysis,a moment-independent importance measure of the basic random variable is proposed,and its properties are analyzed and verified.Based on this work,the importance measure of the basic variable on the failure probability is compared with that on the distribution density of the response.By use of the probability density evolution method,a solution is established to solve two importance measures,which can efficiently avoid the difficulty in solving the importance measures.Some numerical examples and engineering examples are used to demonstrate the proposed importance measure on the failure probability and that on the distribution density of the response.The results show that the proposed importance measure can effectively describe the effect of the basic variable on the failure probability from the distribution density of the basic variable.Additionally,the results show that the established solution on the probability density evolution is efficient for the importance measures. | CUI LiJie,Lü ZhenZhou & ZHAO XinPan School of Aeronautics,Northwestern Polytechnical University,Xi’an 710072,China | 2010 | Science China(Technological Sciences)2010，53，4： | 41 |
| 2 | PHYSICAL MODELING FOR THE MECHANISMS OF BEAD FORMATION DEFECTS BASED ON THE STABILITY OF LIQUID METAL显示文摘Based on the theory of stability of the liquid metal under the action of surface tension,a physical mod- el is established for the mechanisms of the bead formation deferct’ humping’, which is generated during high - speed welding.A boundary function is introduced to correct the model,theoretical results got by the model correspond well with the experimental phenomena. A two - dimensional conducting model is adoopted in the simulation of the temperature field during high - speed welding.Finally, the factors acting upon the stability of liquid metal are analyzed. | S. Y. Yin L. Feng J. Z. Ding and S. J. Chan( 1) Beijing Polytechnic University, Beijing 100022, China 2) National Key Laboratory of Advanced Wdlding Production Technology, HIT, Harbin 150001, China) | 2000 | Acta Metallurgica Sinica(English Letters)2000，13，1： | 28 |
| 3 | COMPUTERIZED SIMULATION AND EXPERIMENTAL RESEARCH ON SOFT-SWITCHING ARC WELDING INVERTER POWER SOURCE显示文摘Based on the existing component models in the Pspice software package, a combined model for Insulat- ed the Bipolar Transistor (IGBT) is established, in which a non - linear is introduced to represent the parasitic capacitance. Using this model, computerized simulation is conducted for the FB - ZVZCS - PWM soft - ewitching converter,the switching and energy-transferring characteristics of the components are analyzed.The simulation results are testified by experiments.It is proved that by abopting appropriate models,computerized simulation becomes an effective tool for investigation of arc welding inverter power source. | S. J. Chen S. Y. Yin L. Feng and L. Y. Li( 1) School of Materials Science and Engineering, Beijing Polytechnic University, Beijing 100022, China 2)National Key Laboratory of Advanced Welding Production Technology, HIT, Harbin 150001, China) | 2000 | Acta Metallurgica Sinica(English Letters)2000，13，1： | 24 |
| 4 | Forming limits under multi-index constraints in NC bending of aluminum alloy thin-walled tubes with large diameters显示文摘With increasing diameters of aluminum alloy thin-walled tubes (AATTs), the tube forming limits, i.e. the minimum bending factors, and their predictions under multi-index constraints including wrinkling, thinning and flattening have been being a key problem to be urgently solved for improving tube forming potential in numerical control (NC) bending processes of AATTs with large diameters. Thus in this paper, a search algorithm of the forming limits is put forward based on a 3D elastic-plastic finite element (FE) model and a wrinkling energy prediction model for the bending processes under axial compression loading (ACL) or not. This algorithm enables to be considered the effects of process parameter combinations including die, friction parameters on the multi-indices. Based on this algorithm, the forming limits of the different size tubes are obtained, and the roles of the process parameter combinations in enabling the limit bending processes are also revealed. The followings are found: the first, within the appropriate ranges of friction and clearances between the different dies and the tubes enabling the bending processes with smaller bending factors, the ACL enables the tube limit bending processes after a decrease of the mandrel ball thickness and diameters; then, without considering the effects of the tube geometry sizes on the tube constitutive equations, the forming limits will be decided by the limit thinning values for the tubes with diameters smaller than 80 mm, while the wrinkling for the tubes with diameters no less than 80 mm. The forming limits obtained from this algorithm are smaller than the analytical results, and reduced by 57.39%; the last, the roles of the process parameter combinations in enabling the limit bending processes are verified by experimental results. | YAN Jing, YANG He, ZHAN Mei & LI Heng College of Materials Science and Engineering, State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China | 2010 | Science China(Technological Sciences)2010，53，2： | 21 |
| 5 | THE INFLUENCE OF CAVITY DAMAGE ON MECHANICAL PROPERTIES OF SUPERPLASTICALLY-DEFORMED MATERIALS AND ITS PREDICTION显示文摘Aluminium alloy LY12CZ sheet without any pre-treatment has been used to study the influence of cavity damage on the mechanical properties of the superplastically-deformed materials room temper- ature. The experimental results show that: (1) the lower the rate of cavitation as the superplastic strain increases, the higher the superplasticity is; (2) the mechanical properties of superplastically- deformed materials at room temperature decrease as the superplastically-deformed strain increases, especially, a noteworthy decrease in elasticity modulus, yield strenth and ultimate strength at room temperature begins to appear as the level of cavitation by area comes up to about 4%, while at the same level the reduction in area drops down a very large quantity. Then, a three-layer back- propagation neural network has been developed to predict the machanichl properties of the superplasti- cally-deformed material.The results acquired from the neural network are very | M. B. Liu, Z. C. Zhao,H. Gao,M. Q. Li and S. C. Wu College of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072, China | 2000 | Acta Metallurgica Sinica(English Letters)2000，13，2： | 18 |
| 6 | ASTUDY OF VALENCE OF YTTRIUM IN Y_2O_3 Mo CATHODE显示文摘The valenceofelementyttrium of Y2 O3 Mocathode materialhasbeenstudied by usingther mal weight analysis, X ray diffraction analysis, Scanning electron microscopy and X rayphotoelectronspectrum . It hasbeen provedthatyttrium oxidecan bereduced by molybdenum carbide. Thereaction between powdered Y2 O3 and Mo2 Ccan happen at 1173 , and Y2 O3may bereduced to metallicyttrium . Afterthepowder mixtureof Y2 O3 and Mo2 Cwasheat treated at1873 K, Yttrium existsin two kinds of chemicalstate- yttrium of zero valence and yttrium ofthreevalences. | J.S.Wang1,2) ,M.L.Zhou2) ,J.X.Zhang2) ,Z.R.Nie2) T.Y.Zuo2) and G.J.Zhang2) 1) State Key Laboratory of Materials Chemistry and Applications,Peking University ,Beijing 100871 ,China2) Schoolof Materials Science and Engineering ,Beijing Polytechnic Univers | 1999 | Acta Metallurgica Sinica(English Letters)1999，12，4： | 16 |
| 7 | Supramolecular complex formation of β-cyclodextrin polymer with substituted salicylic acid or 3-hydroxy-2-naphthoic acid and their electrorheological behaviors显示文摘According to the chemical design, electrorheological properties of supramolecular complex from b-cyclodextrin polymer (b -CDP) were discussed. Six supramolecular complexes of -cyclodextrin polymer with substituted salicylic acid and 3-hydroxy-2-naphthoic acid were syn-thesized by the solid-phase self-assembly method, and their component and structure were characterized by NMR, FT-IR, UV-vis and the fluorescence analysis. Then the electrorheological properties of their suspensions in silicone oil were investigated under DC electric fields. It was found that the yield stresses of these supramolecular complex ER fluids were 7.3—9.8 kPa at 4 kV/mm in DC electric field, which were enhanced by 34%—72% compared with that of pure b-CDP. Among them, that of b-CDP/3-hydroxy-2-naphthoic acid ER fluid was the highest. It was also found that the ER effect of supramolecular complexes can be controlled by changing dif-ferent guests. When the substituted group is at phenyl ring, ER behavior can be slightly adjusted by the different substituted groups, their number as well as their position at phenyl ring. This can be proved by the measurement of dielectric properties. | GAO Ziwei1,2, ZHAO Xiaopeng1, SUN Ping2 & SI Gang2 1. Institute of Electrorheological Technology141#, Department of Applied Physics, Northwestern Polytechnical University, Xian 710072, China 2. Department of Chemistry, School of Chemistry and Material Science, Shaanxi Normal University, Xi’an 710062, China | 2004 | Science China Chemistry2004，47，4： | 15 |
| 8 | Quick image-processing method of UAV without control points data in earthquake disaster area显示文摘The methods of unmanned aerial vehicles images splicing rapidly and rectifying without control points data, only using auxiliary data recorded by unmanned aerial vehicle (UAV) system, were researched. Two algorithms were proposed, including UAV images auto- splicing rapidly after image blocking and UAV images rectifying based on pseudo center points of auxiliary data. When SIFT algorithm for UAV images splicing is applied, the accuracy is very high, but the efficiency is very low. The splicing efficiency is improved greatly based on SIFT algorithm after image blocking. The results show that rectifying accuracy is very high and has no visual dislocation when pseudo center points of auxiliary data is applied. | LI Chang-chun1, ZHANG Guang-sheng1, LEI Tian-jie2, 3, GONG A-du2, 3 1. School of Surveying & Land Information Engineering, Henan Polytechnic University, Jiaozuo 454000, China 2. Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education, Beijing Normal University, Beijing 100875, China 3. Ministry of Civil Affairs/Ministry of Education of China Academy of Disaster Reduction and Emergency Management, Beijing Normal University, Beijing 100875, China | 2011 | 中国有色金属学会会刊:英文版2011，21，S3： | 13 |
| 9 | Recent progress in terahertz science and technology显示文摘The relatively new technique of coherent electromagnetic radiation, in the region of 1012 Hz, has potential to detect the nature of low energy processes in physics, chemistry and biomedicine. In this review article, an overview of recent progress of terahertz (THz) science and technology is presented. The development of the THz generation and detection system, the THz radiation applications which include THz time-domain spectroscopy and T-ray imaging, and the future potential of THz wave research are discussed. | XU Jingzhou, ZHANG Cunlin and ZHANG Xicheng(1. Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, Troy, NY 12180-3590, USA 2. Department of Physics, Capital Normal University, Beijing 100037, China) | 2002 | Progress in Natural Science:Materials International2002，12，10： | 13 |
| 10 | Suitability evaluation for land reclamation in mining area:A case study of Gaoqiao bauxite mine显示文摘Suitability evaluation plays an important role in land reclamation because the choice of evaluation methods affects the accuracy and objectivity of the suitability evaluation results. Furthermore, it influences the decision-making related to land reclamation. An improved method, which is called limit comprehensive conditions method, was developed after different suitability evaluation methods were studied. Based on this method, the reclaimed land of the Gaoqiao bauxite mining area was evaluated. The Gaoqiao mining area was divided into seven evaluation units that were evaluated respectively by selecting evaluation factors and establishing grade standards. The results show that the proposed method is more applicable and easier to handle. Moreover, its evaluation results are more scientific compared with the traditional evaluation methods. The improved method can be beneficial to the rapid monitoring and the effective management of reclaimed land in the opencast mine area. | WANG Shi-dong1, 2, LIU Chang-hua2, ZHANG He-bing2 1. College of Resources Science and Technology, Beijing Normal University, Beijing 100875, China 2. School of Surveying and Land Information Engineering, Henan Polytechnic University, Jiaozuo 454000, China | 2011 | 中国有色金属学会会刊:英文版2011，21，S3： | 13 |
| 11 | Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils显示文摘Studies show positive shifts of inorganic and organic carbon isotope values (δ 13Ccarb and δ 13Ckerogen) from +0.43 (‰ V-PDB) to +3.54 (‰ V-PDB) and from ?29.38 (‰ V-PDB) to ?24.14 (‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2O3 X 15%)) values from 0.015 to 0.144, TOC values from 0.02% to 0.21%, V/Cr values from 0.3 to 2.0, Sr/Ba values from 3.20 to 49.50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, South China, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2, climatic cooling and sea level falling caused by eutrophication, anoxia and organic carbon burial increasing may be important for the mass extinction. | GONG Yiming1,2, XU Ran1, TANG Zhongdao1, SI Yuanlan3 & LI Baohua4 1. Faculty of Earth Science and State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan 430074, China 2. Institute of Resources & Environments, Henan Polytechnic University, Jiaozuo 454003, China 3. Department of Computer Science, South-Central University for Nationalities, Wuhan 430074, China 4. Laboratory of Marine Geology, Tongji University, Shanghai 200092, China | 2005 | Science China Earth Sciences2005，48，10： | 13 |
| 12 | Catalytic Oxidation of Cyclohexene to Adipic Acid with a Reaction-Controlled Phase-Transfer Catalyst显示文摘 | GUO Minglin (College of Materials and Chemical Engineering, Tianjin Polytechnic University, Tianjin 300160, China) | 2003 | 催化学报2003，24，7： | 13 |
| 13 | Exploratory study on new pulse detonation engines显示文摘The worldwide progress in studies on pulse detonation engines (PDE) is briefly reviewed and some results of our exploratory study on PDE are presented. Analysis of thermodynamic cycle is made and the specific impulse formula is improved. A proof-of-principle experiment of a two-phase PDE is successfully carried out, using poor-detonable liquid C8H16/air mixture with a low-energy system (total spark energy of 50 mJ) and a newly developed one-step detonation initiation method. The measured detonation wave pressure ratio is very close to that of C-J detonation. The effects of length, diameter and detonation frequency on PDE performance are experimentally investigated. For liquid hydrocarbon fuel/air mixture, the PDE operation is successfully realized with an engine length of 1000 mm and detonation frequency up to 36 Hz, which has made an important step toward practical PDE. The developed code can be used for simulating PDE operation processes including deflagration to detonation transition (DDT) phenomenon. The numerical results are in good agreement with the experimental ones. | YAN Chuanjun, FAN Wei, HUANG Xiqiao, ZHANG Qun and ZHENG Longxi(Department of Aeroengines, Northwestern Polytechnical University, Xi’an 710072, China) | 2003 | Progress in Natural Science:Materials International2003，13，2： | 12 |
| 14 | Wavelet analysis of sunspot relative numbers显示文摘The time series of the monthly smoothed sun-spot numbers in 1749-2000 is analyzed with the wavelet. The result shows that besides the known time-variation of the period about 11 years, other main periods of the sunspot numbers, such as the periods of about 100 years and so on, vary with time. We suggest that the time-variation of the main periods is the manifestation of the complex variation of sunspot numbers. It is significant to make a thorough study of the character and mechanism of the time-variation of the periods for proving prediction of sunspot numbers, especially for understanding the variation process of sunspot numbers. | HAN Yanben & HAN YonggangNational Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China Department of Applied Mathematics, Beijing Polytechnic University, Beijing 100022, China | 2002 | Chinese Science Bulletin2002，47，7： | 12 |
| 15 | VIBRATION AND CONTROL IN RING ROLLING PROCESS显示文摘1INTRODUCTIONRingrolingisanimportantmechanicalprocesingproceswhichissuitableforproducingd50~100mmringpartsofdiferentmateria... | Hua Lin1, 2, Mei Xuesong2 and Wu Xutang2 1 School of Materials Science and Engineering,Wuhan Automotive Polytechnic University, Wuhan 430070, P. R. China2 School of Mechanical Engineering,Xian Jiaotong University, Xian 710049, P. R. China | 1999 | 中国有色金属学会会刊:英文版1999，9，2： | 11 |
| 16 | The Innovation of CNC Machine Interface Based on DNC System显示文摘This paper describes the innovation schemes of the interface of a CNC machinewhich cannot communicate with a computer by a Direct Numerical Control(DNC)interface andthe functions of a DNC interface system.One architecture of hardware and software of a practi-cal single-chip computer based on DNC interface system developed by the authors is given.Without any change of the original hardware and software,this DNC interface system has beenused to innovate the CNC machine’s interface to implement the direct communication between acomputer and a CNC machine and to achieve no tape transmission of a part program and ma-chine parameters.It has been demonstrated that this DNC interface system has certain practicalvalues in improving the reliability,efficiency and production management of CNC/NC machine. | Luo Jianjun Fan Liuqun Liang Gongqian China Research and Education Center of Plant Engineering,Northwestern Polytechnical University Xi’an,710072,P.R.China | 1997 | International Journal of Plant Engineering and Management1997，2，1： | 11 |
| 17 | A UNIVERSAL ANALYTIC POTENTIAL-ENERGY FUNCTION BASED ON A PHASE FACTOR显示文摘Using a field equation with a phase factor, a universal analytic potential-energy function applied to the interactions between diatoms or molecules is derived, and five kinds of potential curves of common shapes are obtained adjusting the phase factors. The linear thermal expansion coefficients and Young’s moduli of eleven kinds of face-centered cubic (fcc) metals - Al, Cu, Ag, etc. are calculated using the potential-energy function; the computational results are quite consistent with experimental values. Moreover, an analytic relation between the linear thermal expansion coefficients and Young’s moduli of fcc metals is given using the potential-energy function. Finally, the force constants of fifty-five kinds of diatomic moleculars with low excitation state are computed using this theory, and they are quite consistent with RKR (Rydberg-Klein-Rees) experimental values. | C.F. Yu* Deptartment of Physics, College of Science, Xi’an Polytechnic University, Xi’an 710048, China K. Yan Xi’an Modern Nonlinear Science Applying Institute, Xi’an 710061, China D.Z. Liu Section 602, Second Artillery Institute of Engineering, Xi’an 710025, China | 2006 | Acta Metallurgica Sinica(English Letters)2006，19，6： | 11 |
| 18 | Friction of Alloys at High Temperature显示文摘A brief review is given about the friction and wear properties of high temperature alloys. Above a critical temperature, if the oxide becomes ductile, it will flow over the surface and prevent metal-to-metat contact. In order to study the tribology of oxide lubrication. a series of tests were carried out using Cu(ReO4)2 as a lubricant. The effects of time. Surface finish. substrates. load and temperature were investigated. A mechanism of lubrication is proposed in which the surface slip predominates along with mechanical attachment of oxide to the surface. | M.B.Peterson (Wear Sciences, 925 Mallard Circle, Arnold Maryland 21012, USA)(To whom correspondence should be addressed)S.J.Calabrese (Rensselaer Polytechnic Institute, Troy, NY, USA)Shizhuo LI and Xiaoxia JIANG (Institute of Metal Research, Chinese Acad | 1994 | Journal of Materials Science & Technology1994，10，5： | 11 |
| 19 | Microstructure evolution of single crystal copper wires in cold drawing显示文摘The deformation microstructure evolution of single crystal copper wires produced by OCC method has been studied with the help of TEM, EBSD and OM. The results show that there are a small number of dendrites and twins in the undeformed single crystal copper wires. However, it is difficult to observe these dendrites in deformed single crystal copper wires. The structure evolution of deformed single crystal copper wires during drawing process can be divided into three stages. When the true strain is lower than 0.94, macroscopic subdivision of grains is not evident, and the microscopic evolution of deformed structure is that the cells are formed and elongated in drawn direction. When the true strain is between 0.94 and 1.96, mac- roscopic subdivision of grains takes place, and the number of microbands located on {111} and cell blocks is much more than that with the true strain lower than 0.94. When the true strain is larger than 1.96, the macroscopic subdivision of grains becomes more evident than that with the true strain between 0.94 and 1.96, and S-bands structure and lamellar boundaries will be formed. From EBSD analysis, it is found that part of <100> texture resulting from solidifying is transformed into <111> and <112> due to shear deformation, but <100> texture component is still kept in majority. When the true strain is 0.94, the misorientation angle of dislocation boundaries resulting from deformation is lower than 14°. However, when the true strain arrives at 1.96, the misorientation angle of some boundaries will be greater than 50°, and the peak of misorientation angle distribution produced by texture evolution is located in the range between 25° and 30°. | CHEN Jian1,2, YAN Wen1,2, WANG XueYan2 & FAN XinHui2 1 Department of Applied Physics, Northwestern Polytechnical University, Xi’an 710072, China 2 School of Material Science and Chemical Engineering, Xi’an Technological University, Xi’an 710032, China | 2007 | Science China(Technological Sciences)2007，50，6： | 10 |
| 20 | Determination of paleo-pressure for a natural gas pool formation based on PVT characteristics of fluid inclusions in reservoir rocks——A case study of Upper-Paleozoic deep basin gas trap of the Ordos Basin显示文摘It has been proved to be a difficult problem to determine directly trapping pressure of fluid inclusions. Recently, PVT simulation softwares have been applied to simulating the trapping pressure of petroleum inclusions in reservoir rocks, but the reported methods have many limita- tions in practice. In this paper, a method is suggested to calculating the trapping pressure and temperature of fluid inclusions by combining the isochore equations of a gas-bearing aqueous inclusion with its coeval petroleum inclusions. A case study was conducted by this method for fluid inclusions occurring in the Upper-Paleozoic Shanxi Formation reservoir sandstones from the Ordos Basin. The results show that the trapping pressure of these inclusions ranges from 21 to 32 MPa, which is 6─7 MPa higher than their minimum trapping pressure although the trapping temperature is only 2─3℃ higher than the homogenization temperature. The trapping pressure and temperature of the fluid inclusions decrease from southern area to northern area of the basin. The trapping pressure is obviously lower than the state water pressures when the inclusions formed. These data are consistent with the regional geological and geochemical conditions of the basin when the deep basin gas trap formed. | MI Jingkui1,2,XIAO Xianming1,LIU Dehan1,& SHEN Jiagui1 1.State Key Laboratory of Organic Geochemistry,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640,China 2.Institute of Sedimentary Mineral and Resources,Department of Civil Engineering,Xiangtan Polytechnic University,Xiangtan 411201,China | 2004 | Science China Earth Sciences2004，47，6： | 10 |
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