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On Minkowski Constant of Function Fields 认领 引用 被引量：1
1
作者 Hu Weiqun 《Northeastern Mathematical Journal》 1999年第1期69-75,共7页
We give a(Minkowski)constant MK for several kinds of function field K over Fq(including totally real function fields and quadratic function fields)such that each fractional ideal class of the ring OK of integ... We give a(Minkowski)constant MK for several kinds of function field K over Fq(including totally real function fields and quadratic function fields)such that each fractional ideal class of the ring OK of integers contains an integral ideal with degree≤MK. 展开更多
关键词 Minkowski Constant Function Field Fractional Ideal Class Integral Ideal
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Halton-type sequences from global function fields 认领 引用 被引量：1
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作者 NIED ERREITER Harald YEO Anderson SiangJing 《Science China Mathematics》 SCIE EI 2013年第7期1467-1476,共10页
For any prime power q and any dimension s≥1, a new construction of (t, s)-sequences in base q using global function fields is presented. The construction yields an analog of Halton sequences for global function field... For any prime power q and any dimension s≥1, a new construction of (t, s)-sequences in base q using global function fields is presented. The construction yields an analog of Halton sequences for global function fields. It is the first general construction of (t, s)-sequences that is not directly based on the digital method. The construction can also be put into the framework of the theory of (u, e, s)-sequences that was recently introduced by Tezuka and leads in this way to better discrepancy bounds for the constructed sequences. 展开更多
关键词 low-discrepancy sequence （t s）-sequence Halton sequence global function field
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Ideal Class Groups and Subgroups of Real Quadratic Function Fields 认领 引用 被引量：1
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作者 张贤科 王鲲鹏 《Tsinghua Science and Technology》 CAS 2000年第4期372-373,共2页
In this paper, we study the real quadratic function fields K=k(D), given a necessary and sufficient condition for the ideal class group H(K) of any real quadratic function field K to have a cyclic subgroup of order n,... In this paper, we study the real quadratic function fields K=k(D), given a necessary and sufficient condition for the ideal class group H(K) of any real quadratic function field K to have a cyclic subgroup of order n, and obtained eight series of such fields. The ideal class numbers h(O K) of K in the series all have a factor n.[ 展开更多
关键词 algebraic function fields quadratic function field ideal class group continued fractiD
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Bounds of the Ideal Class Numbers of Real Quadratic Function Fields 认领 引用
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作者 KunPengWANG XianKeZHANG 《Acta Mathematica Sinica,English Series》 SCIE 2004年第1期169-174,共6页
The theory of continued fractions of functions is used to give a lower bound for class numbers h(D) of general real quadratic function fields over k = F q (T). For five series of real quadratic function fields K, the ... The theory of continued fractions of functions is used to give a lower bound for class numbers h(D) of general real quadratic function fields over k = F q (T). For five series of real quadratic function fields K, the bounds of h(D) are given more explicitly, e. g., if D = F 2 + c, then h(D) ≥ degF/degP; if D = (SG)2 + cS, then h(D) ≥ degS/degP; if D = (A m + a)2 + A, then h(D) ≥ degA/degP, where P is an irreducible polynomial splitting in K, c ∈ F q . In addition, three types of quadratic function fields K are found to have ideal class numbers bigger than one. 展开更多
关键词 Quadratic function field Ideal class number Continued fraction of function
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SUBGROUPS OF CLASS GROUPS OF ALGEBRAIC QUADRATIC FUNCTION FIELDS 认领 引用
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作者 WANGKUNPENG ZHANGXIANKE 《Chinese Annals of Mathematics,Series B》 SCIE 2003年第3期315-322,共8页
Ideal class groups H(K) of algebraic quadratic function fields K are studied. Necessaryand sufficient condition is given for the class group H(K) to contain a cyclic subgroup of anyorder n, which holds true for both r... Ideal class groups H(K) of algebraic quadratic function fields K are studied. Necessaryand sufficient condition is given for the class group H(K) to contain a cyclic subgroup of anyorder n, which holds true for both real and imaginary fields K. Then several series of functionfields K, including real, inertia imaginary, and ramified imaginary quadratic function fields, aregiven, for which the class groups H(K) are proved to contain cyclic subgroups of order n. 展开更多
关键词 Function field Quadratic extension Class group Class number Continued fraction
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Parametrization of the Quadratic Function Fields Whose Divisor Class Numbers are Divisible by Three 认领 引用
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作者 Wei LI Xian Ke ZHANG 《Acta Mathematica Sinica,English Series》 SCIE 2009年第4期593-596,共4页
A parametrization of quadratic function fields whose divisor class numbers are divisible by 3 is obtained by using free parameters when the characteristics of the fields are not 3.
关键词 quadratic function fields divisor class numbers
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Molecular properties and potential energy function model of BH under external electric field 认领 引用 被引量：12
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作者 伍冬兰 谭彬 +2 位作者 万慧军 张新琴 谢安东 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期194-198,共5页
Using the density functional B3P86/cc-PV5Z method, the geometric structure of BH molecule under different external electric fields is optimized, and the bond lengths, dipole moments, vibration frequencies, and other p... Using the density functional B3P86/cc-PV5Z method, the geometric structure of BH molecule under different external electric fields is optimized, and the bond lengths, dipole moments, vibration frequencies, and other physical properties parameters are obtained. On the basis of setting appropriate parameters, scanning single point energies are obtained by the same method and the potential energy curves under different external fields are also obtained. These results show that the physical property parameters and potential energy curves may change with external electric field, especially in the case of reverse direction electric field. The potential energy function without external electric field is fitted by Morse potential, and the fitting parameters are obtained which are in good agreement with experimental values. In order to obtain the critical dissociation electric parameter, the dipole approximation is adopted to construct a potential model fitting the corresponding potential energy curve of the external electric field. It is found that the fitted critical dissociation electric parameter is consistent with numerical calculation, so that the constructed model is reliable and accurate. These results will provide important theoretical and experimental reference for further studying the molecular spectrum, dynamics, and molecular cooling with Stark effect. 展开更多
关键词 BH molecule potential function model external electric field
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On imaginary quadratic function fields with the ideal class group to be exponent≤2 认领 引用 被引量：2
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作者 HU Weiqun 《Chinese Science Bulletin》 1998年第24期2055-2059,共5页
A necessary condition is presented for the ideal class group of an imaginary quadratic function field K=k(D)(k=F-q(x),2q)to be of exponent≤2.The condition is proved to be sufficient in some cases.An analogue of Loubo... A necessary condition is presented for the ideal class group of an imaginary quadratic function field K=k(D)(k=F-q(x),2q)to be of exponent≤2.The condition is proved to be sufficient in some cases.An analogue of Louboutin’s result in function field case is particularly presented. 展开更多
关键词 imaginary quadratic function field ideal class group ideal class number
The Analytical Potential Energy Function of NH Radical Molecule in External Electric Field 认领 引用 被引量：6
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作者 伍冬兰 谭彬 +2 位作者 万慧军 谢安东 丁大军 《Chinese Physics Letters》 SCIE EI CAS CSCD 2015年第7期34-37,共4页
The geometric structures of an Nit radical in different external electric fields are optimized by using the density functional B3P86/cc-PVSZ method, and the bond lengths, dipole moments, vibration frequencies and IR s... The geometric structures of an Nit radical in different external electric fields are optimized by using the density functional B3P86/cc-PVSZ method, and the bond lengths, dipole moments, vibration frequencies and IR spectrum are obtained. The potential energy curves are gained by the CCSD （T） method with the same basis set. These results indicate that the physical property parameters and potential energy curves may change with the external electric field, especially in the reverse direction electric field. The potential energy function of zero field is fitted by the Morse potential, and the fitting parameters are in good accordance with the experimental data. The potential energy functions of different external electric fields are fitted adopting the constructed potential model. The fitted critical dissociation electric parameters are shown to be consistent with the numerical calculation, and the relative errors are only 0.27% and 6.61%, hence the constructed model is reliable and accurate. The present results provide an important reference for further study of the molecular spectrum, dynamics and molecular cooling with Stark effect. 展开更多
关键词 The Analytical Potential Energy Function of NH Radical Molecule in External Electric Field NH
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Lower Bound for Ideal Class Numbers of Real Quadratic Function Fields 认领 引用
10
作者 张贤科 王鲲鹏 《Tsinghua Science and Technology》 CAS 2000年第4期370-371,共2页
In this paper, the theory of continued fractions of algebraic functions will be used to give a general theorem on lower bounds for class numbers of real quadratic function fields K=k(D). The bounds are given more expl... In this paper, the theory of continued fractions of algebraic functions will be used to give a general theorem on lower bounds for class numbers of real quadratic function fields K=k(D). The bounds are given more explicitly for six types of real quadratic function fields. As a consequence, six classes of real quadratic function fields with ideal class number greater than one are given.[ 展开更多
关键词 real quadratic function fields ideal class number continued fractionp
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Stress Field Analyses of Functionally Gradient Ceramic Tool by FEM 认领 引用
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作者 Ning FAN , Xing AI and Jun ZHAO Department of Mechanical Engineering, Shandong University,Jinan 250061, China 《Journal of Materials Science & Technology》 SCIE EI CAS 2001年第4期466-468,共3页
The cutting properties of the functionally gradient ceramic cutting tools relate closely to the gradient distribution. A cutting model of the functionally gradient ceramic tool is firstly designed in the present paper... The cutting properties of the functionally gradient ceramic cutting tools relate closely to the gradient distribution. A cutting model of the functionally gradient ceramic tool is firstly designed in the present paper. The optimum of gradient distribution is obtained by way of the FEM analyses. 展开更多
关键词 Stress Field Analyses of Functionally Gradient Ceramic Tool by FEM Tool
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Proteins as functional interlayer in organic field-effect transistor 认领 引用 被引量：4
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作者 Wei-Hong Zhang Bo-Jing Jiang Peng Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第8期1339-1344,1469,共6页
The paper summarizes and discusses the recent advances of proteins as functional interlayers in organic field-effect transistors（OFETs）.Specific focus is given on the proteins integrated into the device structure,ei... The paper summarizes and discusses the recent advances of proteins as functional interlayers in organic field-effect transistors（OFETs）.Specific focus is given on the proteins integrated into the device structure,either to act as dielectric materials or to perform as the functional interlayer between the dielectric and the organic semiconductor（OSC）.The main emphasis is give to the location and the specific effect of protein layers in the structure of OFETs.Besides,the possibility of amyloid serving as useful building blocks for OFET is discussed. 展开更多
关键词 Protein Functional interlayer Organic field-effect transistors Dielectric materials Organic semiconductor
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Semi-supervised classification based on Markov Random Field and Robust Error Function 认领 引用
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作者 LIN Qing SHAN Ping-ping +1 位作者 WANG Shi-tong ZHAN Yong-zhao 《通讯和计算机（中英文版）》 2009年第4期1-5,共5页
We focus on semi-supervised classifier, where a decision rule is to be learned from labeled and unlabeled data. A model to semi-supervised classification is proposed to overcome the problem induced by mislabeled sampl... We focus on semi-supervised classifier, where a decision rule is to be learned from labeled and unlabeled data. A model to semi-supervised classification is proposed to overcome the problem induced by mislabeled samples. A new energy function based on robust error function is used in Markov Random Field. Also two algorithms based on iterative condition mode and markov chain monte carlo respectively are designed to infer the label of both labeled and unlabeled samples. Our experiments demonstrate that the proposed method is efficient for real-world dataset. 展开更多
关键词 半管理 Markov随机场 误差函数 能量函数
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Investigation of the Tikhonov Regularization Method in Regional Gravity Field Modeling by Poisson Wavelets Radial Basis Functions 认领 引用 被引量：3
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作者 Yihao Wu Bo Zhong Zhicai Luo 《Journal of Earth Science》 SCIE CAS CSCD 2018年第6期1349-1358,共10页
The application of Tikhonov regularization method dealing with the ill-conditioned problems in the regional gravity field modeling by Poisson wavelets is studied. In particular, the choices of the regularization matri... The application of Tikhonov regularization method dealing with the ill-conditioned problems in the regional gravity field modeling by Poisson wavelets is studied. In particular, the choices of the regularization matrices as well as the approaches for estimating the regularization parameters are investigated in details. The numerical results show that the regularized solutions derived from the first-order regularization are better than the ones obtained from zero-order regularization. For cross validation, the optimal regularization parameters are estimated from L-curve, variance component estimation（VCE） and minimum standard deviation（MSTD） approach, respectively, and the results show that the derived regularization parameters from different methods are consistent with each other. Together with the firstorder Tikhonov regularization and VCE method, the optimal network of Poisson wavelets is derived, based on which the local gravimetric geoid is computed. The accuracy of the corresponding gravimetric geoid reaches 1.1 cm in Netherlands, which validates the reliability of using Tikhonov regularization method in tackling the ill-conditioned problem for regional gravity field modeling. 展开更多
关键词 regional gravity field modeling Poisson wavelets radial basis functions Tikhonov regularization method L-curve variance component estimation（VCE）
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Numerical modeling calculation for the spatial distribution characteristics of horizontal field transfer functions 认领 引用
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作者 龚绍京 陈化然 《Acta Seismologica Sinica(English Edition)》 2001年第6期676-684,共9页
Applying 3-dimension finite difference method, the distribution characteristics of horizontal field transfer functions for rectangular conductor have been computed, and the law of distribution for Re-part and Im-part ... Applying 3-dimension finite difference method, the distribution characteristics of horizontal field transfer functions for rectangular conductor have been computed, and the law of distribution for Re-part and Im-part has been given. The influences of source field period, the conductivity, the buried depth and the length of the conductor on the transfer functions were studied. The extrema of transfer functions appear at the center, the four corners and around the edges of conductor, and move with the edges. This feature demonstrates that around the edges are best places for transfer functions' observation. 展开更多
关键词 numerical modeling 3-D finite difference method horizontal field transfer function spatial distribution characteristics
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Heun Functions Describing Fermions Evolving in Parallel Electric and Magnetic Fields 认领 引用
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作者 MARINA-AURA Dariescu CIPRIAN Dariescu 《Chinese Physics Letters》 SCIE EI CAS CSCD 2015年第7期21-24,共4页
The present work deals with the behavior of fermions moving in a static magnetic induction and a time-harmonic electric field, both oriented along Oz. For the ultra-relativistic particles described by a Heun double co... The present work deals with the behavior of fermions moving in a static magnetic induction and a time-harmonic electric field, both oriented along Oz. For the ultra-relativistic particles described by a Heun double confluent equation, we derive the corresponding wave functions and the conserved current density components. 展开更多
关键词 exp Heun Functions Describing Fermions Evolving in Parallel Electric and Magnetic Fields
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CHAINS OF FUNCTION SPACES OVER EUCLIDIAN SPACES AND LOCAL FIELDS 认领 引用
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作者 Zhaoxi Wang 《Analysis in Theory and Applications》 2009年第1期92-100,共9页
The Lipschitz class Lip(K, α) on a local field K is defined in [10], and an equivalent relationship between the Ho¨lder type space Cα(K)[9] and Lip(K,α) is given. In this note, we give a 'chain of function... The Lipschitz class Lip(K, α) on a local field K is defined in [10], and an equivalent relationship between the Ho¨lder type space Cα(K)[9] and Lip(K,α) is given. In this note, we give a 'chain of function spaces' over Euclidian space by defining higher order continuous modulus in R, and point out that there is no need of higher order continuous modulus for describing the chain of function spaces over local fields. 展开更多
关键词 local field Lipschitz class function space morder continuous modulus morder Lipschitz class
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基于马尔科夫转换场与深度确定性策略梯度算法的VSC-HVDC系统控制参数优化方法 认领 引用 被引量：2
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作者 朱介北 黄闽杰 +3 位作者 俞露杰 欧开健 刘晓龙 贾宏杰 《中国电机工程学报》 EI CSCD 北大核心 2026年第5期1821-1832,I0008,共12页
针对柔性直流输电系统(voltage source converter based high voltage direct current transmission,VSC-HVDC)控制参数设计过程中存在的鲁棒性差、依赖已知电路参数、工程设计经验化等问题,提出一种基于马尔科夫转换场(Markov transiti... 针对柔性直流输电系统(voltage source converter based high voltage direct current transmission,VSC-HVDC)控制参数设计过程中存在的鲁棒性差、依赖已知电路参数、工程设计经验化等问题,提出一种基于马尔科夫转换场(Markov transition field,MTF)与深度确定性策略梯度算法(deep deterministic policy gradient,DDPG)结合的鲁棒性强、不依赖电路参数特性以及可视化的VSC-HVDC控制参数优化设计方法。首先,采用马尔科夫转换场将电路功率、电压等一维时序波形数据转换为二维马尔科夫转换场域图像并使用马尔科夫转换场损失函数(Markov transition field loss,MTFL)判断二维转换域图的数据波动性;其次,将MTFL损失函数与DDPG算法相结合,综合利用MTFL损失函数对系统输出时序数据动态特性评价能力更强的优点和DDPG算法泛化性能优秀的特点,实现VSC-HVDC系统控制参数优化;最后,通过MATLAB模拟和实验结果验证该方法的有效性。 展开更多
关键词 柔性直流输电 控制参数优化 马尔科夫转换场损失函数 马尔科夫转换场 深度确定性策略梯度算法
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Effect of gradient magnetic field on physiochemistry functions of rice seedlings 认领 引用
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《Chinese Rice Research Newsletter》 1999年第1期10-10,共1页
Rice varieties Handao 2,Zhongbai 4,Han-jingzi,and Akihikari were treated with gradi-ent magnetic fileld to study the effect of gradi-ent field on rice.The magnetic field was madeup of 12 plots magnetic plates arranged... Rice varieties Handao 2,Zhongbai 4,Han-jingzi,and Akihikari were treated with gradi-ent magnetic fileld to study the effect of gradi-ent field on rice.The magnetic field was madeup of 12 plots magnetic plates arranged in eachother south and north pole.The magneticstrength was 0-40 mT.Each four varieties wasput under the magnetic plate 15 cm away,andwent through the magnetic field with the speedof 20 cm/s.The same varieties without thetreatment were used as CK.Both of the seedswere soaked in water for 48 h in room temper-ature,and then sprouted on the porcelain platewith absorbed water paper.When the 展开更多
关键词 Effect of gradient magnetic field on physiochemistry functions of rice seedlings
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Revisiting the elastic solution for an inner-pressured functionally graded thick-walled tube within a uniform magnetic field 认领 引用 被引量：1
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作者 Libiao XIN Yanbin LI +2 位作者 Dongmei PAN Guansuo DUI Chengjian JU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2018年第10期1485-1498,共14页
In this paper, the mechanical responses of a thick-walled functionally graded hollow cylinder subject to a uniform magnetic field and inner-pressurized loads are studied. Rather than directly assume the material const... In this paper, the mechanical responses of a thick-walled functionally graded hollow cylinder subject to a uniform magnetic field and inner-pressurized loads are studied. Rather than directly assume the material constants as some specific function forms displayed in pre-studies, we firstly give the volume fractions of different constituents of the functionally graded material(FGM) cylinder and then determine the expressions of the material constants. With the use of the Voigt method, the corresponding analytical solutions of displacements in the radial direction, the strain and stress components, and the perturbation magnetic field vector are derived. In the numerical part, the effects of the volume fraction on the displacement, strain and stress components, and the magnetic perturbation field vector are investigated. Moreover, by some appropriate choices of the material constants, we find that the obtained results in this paper can reduce to some special cases given in the previous studies. 展开更多
关键词 functionally graded material(FGM) thick-walled tube elasticity solution magnetic field perturbation of magnetic field vector
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