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| 1 | Targeting Gene-Virotherapy of Cancer and its prosperity显示文摘为癌症的基因和病毒的治疗显示出一些治疗学的效果,但是有真实突破的缺乏。为了达到肿瘤的完全的消除的目标,在动物的异种皮移植当模特儿,我们开发了叫的新策略指向癌症的 Gene-Virotherapy,它试图联合基因治疗和 virotherapy 的优点。这新策略独自比基因或病毒的治疗生产了更强壮的反肿瘤效果。肿瘤特定的 replicative 侵入人体气管粘膜的病菌向量,指定了为 ZD55,被侵入人体气管粘膜的病菌的 55kDa E1B 区域的删除构造。结果病毒的构造不仅由明确地指向 p53 保留类似的功能到 ONYX-015 否定肿瘤,而且允许各种各样的治疗学的基因到的插入由于最新介绍的克隆的地点形成适当 ZD55 衍生物,与原来的 ONYX-015 病毒不可行的一项任务。我们证明反肿瘤一如此的衍生物完成, ZD55-IL-24,比 ZD55 virotherapy 或 Ad-IL-24 基因治疗的是乘更多的有势力的至少 100。不过,由 ZD55-IL-24 的使用的肿瘤质量的完全的消除是仅仅在一些然而并非所有老鼠观察了,显示那一治疗学的基因不对“痊愈”足够这些老鼠。有互补或合作的效果的基因是什么时候,独立克隆进 ZD55 向量并且在联合使用了(指定了为双基因治疗策略) ,好一些的结果被获得;并且如果二合适的基因被选择,在所有老鼠完成所有异种皮移植肿瘤群众的完全的消除是可能的。更全面的研究将多半为临床的试用基于这新策略导致一个协议。最后,为癌症治疗的两倍控制指向的病毒双的基因治疗的概念,和在癌症干细胞的最近的进步的含意也被讨论。 | Xin Yuan Liu~(1,2) ~1Institute of Biochemistry and Cell Biology,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,320 Yue Yang Road,Shanghai 200031,China ~2Xinyuan Institute of Medicine and Biotechnology,School of Life Science,Zhejiang Sci-Tech University,Hangzhou 310018,China | 2006 | Cell Research2006,16,11: | 32 |
| 2 | Research on the mechanics of underwater supersonic gas jets显示文摘An experimental research was carried out to study the fluid mechanics of underwater supersonic gas jets. High pressure air was injected into a water tank through converging-diverging nozzles (Laval nozzles). The jets were operated at different conditions of over-, full- and under-expansions. The jet sequences were visualized using a CCD camera. It was found that the injection of supersonic air jets into water is always accompanied by strong flow oscillation, which is related to the phenomenon of shock waves feedback in the gas phase. The shock wave feedback is different from the acoustic feedback when a supersonic gas jet discharges into open air, which causes screech tone. It is a process that the shock waves enclosed in the gas pocket induce a periodic pressure with large amplitude variation in the gas jet. Consequently, the periodic pressure causes the jet oscillation including the large amplitude expansion. Detailed pressure measurements were also conducted to verify the shock wave feedback phenomenon. Three kinds of measuring methods were used, i.e., pressure probe submerged in water, pressure measurements from the side and front walls of the nozzle devices respectively. The results measured by these methods are in a good agreement. They show that every oscillation of the jets causes a sudden increase of pressure and the average frequency of the shock wave feedback is about 5–10 Hz. | SHI HongHui1, WANG BoYi2 & DAI ZhenQing2 1 College of Mechanical Engineering and Automation, Zhejiang Sci-Tech University, Hangzhou 310018, China 2 State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China | 2010 | Science China(Physics,Mechanics & Astronomy)2010,53,3: | 22 |
| 3 | Quasi-static Analysis of Thrust-loaded Angular Contact Ball Bearings Part Ⅰ:Theoretical Formulation显示文摘Ball bearings play an important role in various rotating machineries,but the complicated kinematic and tribological features of ball bearings make many aspects of their operating behaviors still inconclusive.Most theoretical analyses of ball bearings up to date are based on either the hypothesis of race control or other empirical models to determine the ball motion of ball bearings,but none of these strategies can reveal and consequently employ the intrinsic coupling mechanism between the spin and the tangential traction of contacting bodies rolling upon one another.To remedy the deficiency of current analytical models for ball bearing analysis,the rolling contact theory is employed to establish an explicit link between motions and interactions within ball bearings.A differential slip model is established to precisely define the slip component due to the significant curvature of the common contact patches between the ball and inner/outer raceways.The creepage and the spin ratio are formulated to accurately define the relative rigid motion between the ball and the inner/outer raceway.Then a quasi-static analytical model is established that can accurately determine the motions of the balls and races of the ball bearing.It can also give a vivid description of the slip and traction distributions within the contact area.The analytical model can be effectively used to analyze the operational conditions and tribological features of solid-lubricated ball bearings.It can also be used optimize the construction of ball bearings for specific applications. | CHEN Wenhua1,2,MA Zikui1,GAO Liang1,LI Xinglin3,and PAN Jun2 1 Institute of Mechanical Design,Zhejiang University,Hangzhou 310027,China 2 Institute of Mechanical Design and Manufacturing,Zhejiang Sci-Tech University,Hangzhou 310018,China 3 State Testing Laboratory of Hangzhou Bearing Test & Research Center,Hangzhou 310022,China | 2012 | Chinese Journal of Mechanical Engineering2012,25,1: | 16 |
| 4 | Irrigation Water Use Efficiency of Farmers and Its Determinants: Evidence from a Survey in Northwestern China显示文摘Irrigation water shortage is becoming an increasingly serious problem in agricultural production. In this case, it is very important for policy makers to take measures to improve irrigation water use efficiency, especially in the water-scarce areas. In this paper, the data envelopment analysis (DEA) techniques, based on the concept of input-specific technical efficiency were used to develop farm-level technical efficiency measures and sub-vector efficiencies for irrigation water use. The Tobit regression technique was then adopted to identify the factors that influence irrigation water efficiency differentials under the shortage of water resources. Based on a sample data of 432 wheat farmers in northwestern China, our experimental results of the DEA analysis showed the average technical efficiency of 0.6151. It suggested that wheat farmers could increase their production by as much as 38.49% by using inputs more efficiently. Further, the mean irrigation water efficiency of 0.3065, suggested that wheat farmers could produce the same quantity of wheat using the same quantity of inputs but with 69.35% less water. The results of the Tobit regression analysis showed that the farmer’s age, income, education level, and the farm size tended to affect the degree of irrigation water efficiency positively, and the channel conditions and different irrigation methods made a significant impact on irrigation water use efficiency. Furthermore, the arrangements of exclusive water property rights and competitive water price mechanism have effectively encouraged the water saving behavior of farmers. These results are valuable for policy makers since it could help to guide policies towards high irrigation water use efficiency. | WANG Xue-yuan College of Economics, Zhejiang Gongshang University, Hangzhou 310018, P.R.China | 2010 | Agricultural Sciences in China2010,9,9: | 16 |
| 5 | Geometric construction of energy-minimizing Bézier curves显示文摘Modeling energy-minimizing curves have many applications and are a basic problem of Geometric Modeling.In this paper,we propose the method for geometric design of energy-minimizing B′ezier curves.Firstly,the necessary and sufficient condition on the control points for B′ezier curves to have minimal internal energy is derived.Based on this condition,we propose the geometric constructions of three kinds of B′ezier curves with minimal internal energy including stretch energy,strain energy and jerk energy.Given some control points,the other control points can be determined as the linear combination of the given control points.We compare the three kinds of energy-minimizing B′ezier curves via curvature combs and curvature plots,and present the collinear properties of quartic energy-minimizing B′ezier curves.We also compare the proposed method with previous methods on efficiency and accuracy.Finally,several applications of the curve generation technique,such as curve interpolation with geometric constraints and modeling of circle-like curves are discussed. | XU Gang 1,4,5,WANG GuoZhao 2 & CHEN WenYu 2,3 1 Institute of Graphics and Image,Hangzhou Dianzi University,Hangzhou 310018,China 2 Department of Mathematics,Zhejiang University,Hangzhou 310027,China 3 School of Computer Engineering,Nanyang Technological University,639798,Singapore 4 Galaad,INRIA Sophia-Antipolis,2004 Route des Lucioles,06902,France 5 State Key Lab of CAD & CG,Zhejiang University,Hangzhou 310027,China | 2011 | Science China(Information Sciences)2011,54,7: | 15 |
| 6 | Noether-type theorem for discrete nonconservative dynamical systems with nonregular lattices显示文摘We investigate Noether symmetries and conservation laws of the discrete nonconserved systems with nonregular lattices. The operators of discrete transformation and discrete differentiation to the right and left are introduced for the systems. Based on the invariance of discrete Hamilton action on nonregular lattices of the systems with the nonconserved forces under the infinitesimal transformations with respect to the time and generalized coordinates, we give the discrete analog of generalized variational formula. From this formula we derive the discrete analog of generalized Noether-type identity, and then we present the generalized quasi-extremal equations and properties of these equations for the systems. We also obtain the discrete analog of Noether-type conserved laws and the discrete analog of generalized Noether theorems for the systems. We discuss an example to illustrate these results. | FU JingLi1, CHEN LiQun2 & CHEN BenYong3 1 Institute of Mathematical Physics, Zhejiang Sci-Tech University, Hangzhou 310018, China 2 Department of Mechanics, Shanghai University, Shanghai 200072, China 3 Faculty of Mechanical-Engineering & Automation, Zhejiang Sci-Tech University, Hangzhou 310018, China | 2010 | Science China(Physics,Mechanics & Astronomy)2010,53,3: | 11 |
| 7 | Noether-type theory for discrete mechanico-electrical dynamical systems with nonregular lattices显示文摘We investigate Noether symmetries and conservation laws of the discrete mechanico-electrical systems with nonregular lattices.The operators of discrete transformation and discrete differentiation to the right and left are introduced for the systems.Based on the invariance of discrete Hamilton action on nonregular lattices of the systems with the dissipation forces under the infinitesimal transformations with respect to the time,generalized coordinates and generalized charge quantities,we work out the discrete analog of the generalized variational formula.From this formula we derive the discrete analog of generalized Noether-type identity,and then we present the generalized quasi-extremal equations and properties of these equations for the systems.We also obtain the discrete analog of Noether-type conserved laws and the discrete analog of generalized Noether theorems for the systems.Finally we use an example to illustrate these results. | FU JingLi1,CHEN LiQun2 & CHEN BenYong3 1 Institute of Mathematical Physics,Zhejiang Sci-Tech University,Hangzhou 310018,China 2 Department of Mechanics,Shanghai University,Shanghai 200072,China 3 Faculty of Mechanical-Engineering & Automation,Zhejiang Sci-Tech University,Hangzhou 310018,China | 2010 | Science China(Physics,Mechanics & Astronomy)2010,53,9: | 8 |
| 8 | Effective generalized equations of secure hyperelliptic curve digital signature algorithms显示文摘A hyperelliptic curve digital signature algorithm (HECDSA) can be viewed as the hyperelliptic curve analogue of the standard digital signature algorithm (DSA). This article discusses divisor evaluations,the basic HECDSA,variants,two HECDSA equations and a 4-tuple HECDSA scheme,and puts forward a generalized equation for HECDSA. From this generalized equation,seven general HECDSA types are derived based on the efficiency requirements. Meanwhile,the securities of these general HECDSA types are analyzed in detail. | YOU Lin ,SANG Yong-xuan College of Communication Engineering,Hangzhou Dianzi University,Hangzhou 310018,China | 2010 | The Journal of China Universities of Posts and Telecommunications2010,17,2: | 7 |
| 9 | Quasi-static Analysis of Thrust-loaded Angular Contact Ball Bearings Part Ⅱ:Results and Discussion显示文摘Ball bearings are widely employed mechanical components characterized by high precision and quality,and usually play important roles in various rotary machines and mechanisms.Many advanced applications require a deep understanding of their various kinematic and tribological characteristics that are essential to predict the fatigue endurance,relieve the vibration and minimize the power dissipation of ball bearings in particular applications.An angular contact ball bearing under a specified operating condition is simulated with the quasi-static/creepage analytical model proposed in the preceding article.The results demonstrate that the ball bearing is a statically determinate system.That the balls spin on both inner and outer races means the ball is controlled by neither the inner nor the outer raceway.The friction between the ball and raceway renders the inner and outer contact angles unequal.The larger the coefficient of friction is,the larger the angle deviation.The tangential traction perpendicular to the rolling direction due to the spin induces a gyro-like rotation of the ball with respect to the raceway even if no inertial effects are considered.The tangential elastic compliance of contacting surfaces gives rise to locked areas within the contact patch and transforms the sliding lines from circles into spirals.The differential slip due to the close conformity of the ball and raceway makes the sliding and traction distributions asymmetric,which will influence the location of the spinning center of the ball with respect to the raceway.The quasi-static/creepage model can be used to reveal the operating behaviors of ball bearings running under steady conditions and to optimize the design of ball bearings for specific applications. | CHEN Wenhua1,2,MA Zikui1,GAO Liang1,LI Xinglin3,and PAN Jun2 1 Institute of Mechanical Design,Zhejiang University,Hangzhou 310027,China 2 Institute of Mechanical Design and Manufacturing,Zhejiang Sci-Tech University,Hangzhou 310018,China 3 State Testing Laboratory of Hangzhou Bearing Test & Research Center,Hangzhou 310022,China | 2012 | Chinese Journal of Mechanical Engineering2012,25,1: | 7 |
| 10 | The Nother and Riemann-Roch type theorems for piecewise algebraic curve显示文摘A piecewise algebraic curve is a curve determined by the zero set of a bivariate spline function. In this paper, the Nother type theorems for Cμpiecewise algebraic curves are obtained. The theory of the linear series of sets of places on the piecewise algebraic curve is also established. In this theory, singular cycles are put into the linear series, and a complete series of the piecewise algebraic curves consists of all effective ordinary cycles in an equivalence class and all effective singular cycles which are equivalent specifically to any effective ordinary cycle in the equivalence class. This theory is a generalization of that of linear series of the algebraic curve. With this theory and the fundamental theory of multivariate splines on smoothing cofactors and global conformality conditions, and the results on the general expression of multivariate splines, we get a formula on the index, the order and the dimension of a complete series of the irreducible Cμpiecewise algebraic curves and the degree, the genus and the smoothness of the curves, hence the Riemann-Roch type theorem of the Cμpiecewise algebraic curve is established. | Yi-sheng LAI & Ren-hong WANG College of Statistics and Mathematics, Zhejiang Gongshang University, Hangzhou 310018, China Institute of Mathematical Sciences, Dalian University of Technology, Dalian 116024, China | 2007 | Science China Mathematics2007,50,2: | 5 |
| 11 | Numerical Simulation and Experiment Analyses for the Gas-liquid Two-phase Vortex Pump显示文摘Based on the gas-liquid two-phase mixture transportation test,the k-ε-Ap turbulence model was applied to simulate the two-phase turbulent flow in a vortex pump.By comparing the simulation and experiment results,inner flow features were revealed.The bubbles in the channel distribute mainly at the pressure side of the blades,and the aggregation degree of the bubbles is enhanced with an increase in inlet gas volume fraction.Experimental results indicate that the influence of the gas phase on vortex pump performance is small when the gas volume fraction is less than 10%.When the gas volume fraction continuously increases to 15%,the characteristic curves abruptly drop due to the gas blocking phenomenon. | Y.Li,Z.C.Zhu,W.Q.He,Y.P.Wang and B.L.Cui The Lab of Multi-phase Fluid Transmission Technology,Zhejiang Sci-Tech University,Hangzhou 310018,China | 2010 | Journal of Thermal Science2010,19,1: | 5 |
| 12 | Factors Affecting Small Axial Cooling Fan Performance显示文摘Many factors such as outer diameter,hub ratio,blade numbers,shape and stagger angle affect the performance of small cooling fans.A small cooling fan was simulated using CFD software for three blade stagger angles (30.5°,37.5°,44.5°)and obtained the internal flow field and the static characteristics.Research indicated that the stagger angle has an obvious effect on the static characteristics of a fan.For flow rates below 0.0104 m3/s,total pressure is the greatest when the stagger angle is 37.5°;flow rates higher than 0.0104 m3/s,the total pressure is greatest when the stagger angle is 44.5° For the same flow rates,the velocity at inlet of pressure surface increases with increasing stagger angle,but the change of velocity on the suction surface is very small.For one model,vortices and the speed of revolution surfaces decrease with tip clearance increasing.But for other three models,increasing the stagger angle,the vortex intensity and speed of revolution surfaces at same height tip clearance increases,simultaneously,the position of vortex offset from the top of the rotor blade to the suction surface. | Lihong Wang,Yingzi Jin,Baoling Cui,Yuzhen Jin,Jin Lin,Yanping Wang and Chuanyu Wu College of Mechanical Engineering & Automation,Zhejiang Sci-Tech University,Xiasha Education Zone,Hangzhou 310018,China | 2010 | Journal of Thermal Science2010,19,2: | 4 |
| 13 | Stability of multiquadric quasi-interpolation to approximate high order derivatives显示文摘Numerical simulation of the high order derivatives based on the sampling data is an important and basic problem in numerical approximation,especially for solving the differential equations numerically.The classical method is the divided difference method.However,it has been shown strongly unstable in practice.Actually,it can only be used to simulate the lower order derivatives in applications.To simulate the high order derivatives,this paper suggests a new method using multiquadric quasi-interpolation.The stability of the multiquadric quasi-interpolation method is compared with the classical divided difference method.Moreover,some numerical examples are presented to confirm the theoretical results.Both theoretical results and numerical examples show that the multiquadric quasi-interpolation method is much stabler than the divided difference method.This property shows that multiquadric quasi-interpolation method is an efficient tool to construct an approximation of high order derivatives based on scattered sampling data even with noise. | MA LiMin 1,2 & WU ZongMin 1,1 Shanghai Key Laboratory for Contemporary Applied Mathematics,School of Mathematical Sciences,Fudan University,Shanghai 200433,China 2 Department of Information and Computer Science,Zhejiang Gongshang University,Hangzhou 310018,China | 2010 | Science China Mathematics2010,53,4: | 4 |
| 14 | Magnetic properties of cobalt-based oxypnictide SmCoAsO显示文摘The magnetic properties of cobalt-based oxypnictides SmCoAsO are investigated by measuring magnetization,magnetoresistance and specific heat.The compound undergoes a ferromagnetic(FM) transition around Tc of 80 K,and a ferromagnetic to antiferromagnetic(AFM) transition below TN1 of about 45 K,and finally an AFM order of Sm ion at TN2 of 5.6 K.The weak FM order should originate from the itinerant 3d electrons of Co ions in the CoAs layers.We propose that the magnetic structure should be A-type AFM,which means that the FM order remains within the CoAs layer and the magnetic coupling between the CoAs layers becomes AFM below TN1 of 45 K.The AFM coupling between the CoAs layers should be very weak.A magnetic field μ0H of about 2 T may cause an AFM-FM metamagnetic transition.A rich magnetic phase diagram is established and the interplay between the 3d electrons of Co ions and 4f electrons of Sm ions is discussed. | LI YuKe1,TONG Jun1,HAN Han1,ZHANG Li2,TAO Qian1,CAO GuangHan1 & XU ZhuAn1* 1 Department of Physics,Zhejiang University,Hangzhou 310027,China 2 Department of Physics,China Jiliang University,Hangzhou 310018,China | 2010 | Science China(Physics,Mechanics & Astronomy)2010,53,7: | 3 |
| 15 | Influence of Casting Technique on the Mechanical Properties of Bimetal Composites显示文摘According to the characteristic of two liquid and bimetal composite interface,the influence of the casting techniques on the interface microstructure,wear and comprehensive properties were researched by using scanning electron microscope (SEM) and energy dispersive X-ray analysis (EDAX).The results show that the casting technique has an effect on the surface quality and the stress state of the composites,but also has great effect on the interface microstructure,morphology and constitute phase.In this paper,a special casting technology was used to prepare the bimetal composites.No two-metal mixture layer was observed at the interface.On the contrary,a metallurgy interface was found,which provides high working security.A product rate of 95% was achieved by this special casting process.The service life is 50% higher than that of the commercial products. | RONG Shou-fan 1,GUO Ji-wei 1,ZHU Yong-chang 1,BIAN Wen-li 2,DU Jie-min 1 (1.Jiamusi University,Heilongjiang Province 154007,China 2.Zhejiang Conservancy and Hydropower College,Zhejiang Province 310018,China) | 2011 | Journal of Iron and Steel Research(International)2011,18,S1: | 3 |
| 16 | Symmetries and exact solutions of discrete nonconservative systems显示文摘Based on the property of the discrete model entirely inheriting the symmetry of the continuous system,we present a method to construct exact solutions with continuous groups of transformations in discrete nonconservative systems.The Noether's identity of the discrete nonconservative system is obtained.The symmetric discrete Lagrangian and symmetric discrete nonconservative forces are defined for the system.Generalized quasi-extremal equations of discrete nonconservative systems are presented.Discrete conserved quantities are derived with symmetries associated with the continuous system.We have also found that the existence of the one-parameter symmetry group provides a reduction to a conserved quantity;but the existence of a two-parameter symmetry group makes it possible to obtain an exact solution for a discrete nonconservative system.Several examples are discussed to illustrate these results. | FU JingLi1,LI XiaoWei2,LI ChaoRong1,ZHAO WeiJia3 & CHEN BenYong4 1 Institute of Mathematical Physics,Zhejiang Sci-Tech University,Hangzhou 310018,China 2 Department of Physics,Shangqiu Normal University,Shangqiu 476000,China 3 Department of Mathematics,Qingdao University,Qingdao 266071,China 4 Faculty of Mechanical Engineering & Automation,Zhejiang Sci-Tech University,Hangzhou 310018,China | 2010 | Science China(Physics,Mechanics & Astronomy)2010,53,9: | 3 |
| 17 | Large-deviation probabilities for maxima of sums of subexponential random variables with application to finite-time ruin probabilities显示文摘We establish an asymptotic relation for the large-deviation probabilities of the maxima of sums of subexponential random variables centered by multiples of order statistics of i.i.d.standard uniform random variables.This extends a corresponding result of Korshunov.As an application,we generalize a result of Tang,the uniform asymptotic estimate for the finite-time ruin probability,to the whole strongly subexponential class. | JIANG Tao School of Finance,Zhejiang Gongshang University,Hangzhou 310018,China | 2008 | Science China Mathematics2008,51,7: | 2 |
| 18 | Control problems of an age-dependentpredator-prey system显示文摘This paper is concerned with optimal harvesting problems for a system consisting oftwo populations with age-structure and interaction of predator-prey. Existence and uniquenessof non-negative solutions to the system and the continuous dependence of solutions on controlvariables are investigated. Existence of optimal policy is discussed, optimality conditions arederived by means of normal cone and adjoint system techniques. | HE Ze-rong WANG Hai-tao Institute of Operational Research and Cybernetics,Hangzhou Dianzi University,Hangzhou 310018,China | 2009 | Applied Mathematics(A Journal of Chinese Universities)2009,24,3: | 2 |
| 19 | On optimal binary signed digit representations of integers显示文摘Binary signed digit representation (BSD-R) of an integer is widely used in computer arithmetic, cryptography and digital signal processing. This paper studies what the exact number of optimal BSD-R of an integer is and how to generate them entirely. We also show which kinds of integers have the maximum number of optimal BSD-Rs. | WU Ting ZHANG Min DU Huan-qiang WANG Rong-bo College of Computer Science, Hangzhou Dianzi University, Hangzhou 310018, China | 2010 | Applied Mathematics(A Journal of Chinese Universities)2010,25,3: | 2 |
| 20 | Almost sure central limit theorems for random functions显示文摘Let {Xn,-∞< n <∞} be a sequence of independent identically distributed be a random function such that Tn = ASn+ Rn,where supnE|Rn|<∞ and Rn = o(√n)a.s.,or Rn = O(n1/2-2γ) a.s.,0 <γ< 1/8.In this paper,we prove the almost sure central limit theorem (ASCLT) and the function-typed almost sure central limit theorem (FASCLT) for the random function Tn.As a consequence,it can be shown that ASCLT and FASCLT also hold for U-statistics,Von-Mises statistics,linear processes,moving average processes,error variance estimates in linear models,power sums,product-limit estimators of a continuous distribution,product-limit estimators of a quantile function,etc. | LU Chuanrong, QIU Jin & XU Jianjun School of Mathematics and Statistics, Zhejiang University of Finance and Economics, Hangzhou 310018, China Department of Mathematics, Zhejiang University, Hangzhou 310028, China | 2006 | Science China Mathematics2006,49,12: | 2 |