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山桃花
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作者 卢元隆 梁旋程 《音乐创作》 北大核心 2015年第10期68-71,共4页
关键词 程曲
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小烤房烤烟烧柴草 成本低质量好
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作者 刘呋喃 刘友杰 《中国烟草科学》 CSCD 1990年第3期48-49,共2页
山东省青州市是粮烟产区,特别是农村实行生产责任制以来,小麦连年增产,柴草(均指麦糠、麦穰)逐年增多。适应新形势的小烤房的兴建,似雨后春笋,至1986年全市就实现了烤烟小炉化。在煤源不足,价格猛长及烤烟小炉化的情况下,如何利用当地... 山东省青州市是粮烟产区,特别是农村实行生产责任制以来,小麦连年增产,柴草(均指麦糠、麦穰)逐年增多。适应新形势的小烤房的兴建,似雨后春笋,至1986年全市就实现了烤烟小炉化。在煤源不足,价格猛长及烤烟小炉化的情况下,如何利用当地丰富的柴草资源,缓解煤炭供应紧张状况,降低烤烟成本,实行小烟炉用柴草烤烟。开拓烤烟燃料的新途径。这个问题引起有关领导的重视和关注。 展开更多
关键词 烤烟房 烤房 烤烟质量 上等烟 上中等 煤源 生产责任制 山东省青州市 道洪 程曲
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Oscillatory Criteria for a Class of Boundary Value Problem of Nonlinear Hyperbolic Equations *L
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作者 王培光 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 1999年第1期20-24,共5页
Aim To study a class of boundary value problem of hyperbolic partial functional differential equations with continuous deviating arguments. Methods An averaging technique was used. The multi dimensional problem was... Aim To study a class of boundary value problem of hyperbolic partial functional differential equations with continuous deviating arguments. Methods An averaging technique was used. The multi dimensional problem was reduced to a one dimensional oscillation problem for ordinary differential equations or inequalities. Results and Conclusion The known results of oscillation of solutions for a class of boundary value problem of hyperbolic partial functional differential equations with discrete deviating arguments are generalized, and the oscillatory criteria of solutions for such equation with two kinds of boundary value conditions are obtained. 展开更多
关键词 continuous deviating arguments hyperbolic equation boundary value problem OSCILLATION
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Converting GPS height by a new method based on neural networks
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作者 胡伍生 沙月进 《Journal of Southeast University(English Edition)》 EI CAS 2003年第1期53-57,共5页
The adjusted GPS height is the height above the surface of the WGS-84ellipsoid. It is necessary to convert a GPS height into a normal height in engineering. The conicoidfitting method (CFM) and the neural networks met... The adjusted GPS height is the height above the surface of the WGS-84ellipsoid. It is necessary to convert a GPS height into a normal height in engineering. The conicoidfitting method (CFM) and the neural networks method (NNM) are used for this purpose, but each ofthem has its advantages and disadvantages. After studying these two methods, a new method (abbr.CF&NNM) is conceived. The procedure of the CF&NNM is introduced. A practical engineering example isused to study these three different methods. The results by the three methods are listed. The CF&NNMmethod can produce better results than either the CFM or the NNM in deriving normal height from GPSheight. The theory of the CF&NNM method is analyzed. 展开更多
关键词 neural networks algorithm of BP GPS height CF&NNM
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The Conformally Symmetric K-Contact Manifolds
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作者 郭震 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第1期5-10,共6页
In this paper, we establish a differential equation about scalar curvature of conformally flat K-contact manifolds, and prove that a conformally symmetric K-contact manifold is a Riemann manifold with constant curvatu... In this paper, we establish a differential equation about scalar curvature of conformally flat K-contact manifolds, and prove that a conformally symmetric K-contact manifold is a Riemann manifold with constant curvature 1. At the same time, the results on Sasaki manifolds which are given by Miyazaawa and Yamagushi are generalized to K-contact manifolds. 展开更多
关键词 Conformally symmetric Contact Structure Killing vector field
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Oscillations of the Solutions of Hyperbolic Partial Differential Equations of Neutral Type 被引量:4
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作者 刘安平 曹少琛 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第2期7-13,共7页
In this paper, oscillatory properties of solutions of certain nonlinear hyperbolic partial differential equations are investigated and a series of sufficient conditions for oscillations of the equations are establishe... In this paper, oscillatory properties of solutions of certain nonlinear hyperbolic partial differential equations are investigated and a series of sufficient conditions for oscillations of the equations are established. The results fully indicate that the oscillations are caused by delay. 展开更多
关键词 HYPERBOLIC DELAY OSCILLATION nonlinear NEUTRAL
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李晓明抗税、伤害财政干部被依法逮捕
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作者 杨明忠 唐必舟 王艾琼 《财政与发展》 1994年第9期25-,共1页
7月3日,抗税、伤害财政干部的李晓明被依法逮捕.今年4月5日,天门市李场乡财所干部在范金木所长的带领下,在该乡黄店集贸市场执行公务,进行农业特产税稽查补征工作.
关键词 财政干部 程曲 农业特产税 执行公务 范金 市人民法院 《税法》 鼻骨折
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The Global Uniqueness of Solutions for a Class of Inverse Problem in 1-D Wave Equations of Hyperbolic Type 被引量:1
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作者 叶留青 司清亮 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期107-110,共4页
This paper has given the global uniquene ss theory of solutions for a class of inverse problem in 1_D Wave equation of hype rbolic type.
关键词 D Wave equations of hyperbolic inverse proble m global uniqueness
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Blow-up of Solution for a Nonlinear Hyperbolic Equation
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作者 陈翔英 刘维先 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第2期106-110,共5页
In this paper, the existence and uniqueness of the local generalized solution of the initial boundary value problem for a nonlinear hyperbolic equation are proved by the contraction mapping principle and the sufficien... In this paper, the existence and uniqueness of the local generalized solution of the initial boundary value problem for a nonlinear hyperbolic equation are proved by the contraction mapping principle and the sufficient conditions of blow_up of the solution in finite time are given. 展开更多
关键词 nonlinear hyperbolic equation initial boundary value problem local generalized solution blow_up of solution
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CALCULATIONS OF THE PHASE EQUILIBRIA AND CRITICAL CURVES WITH THE EQUATION OF STATE FOR BINARY MIXTURES
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作者 田宜灵 乔瑞平 +1 位作者 宋瑛 任晓文 《Transactions of Tianjin University》 EI CAS 1998年第1期62-67,共6页
A rational equation of state of the perturbation type with a repulsion and attraction term has been applied to reproduce critical curves of six different binary systems up to high temperatures and pressures. A square ... A rational equation of state of the perturbation type with a repulsion and attraction term has been applied to reproduce critical curves of six different binary systems up to high temperatures and pressures. A square well potential for intermolecular interaction is used. With pairwise combination rules for these potentials three adjustable parameters are needed. The experimental critical point and phase equilibrium data are compared with the values predicted using the equation of state. Good agreement is obtained for the analysis of the critical pressure composition data and molar volumes. 展开更多
关键词 equation of state binary system critical curve phase equilibrium high temperature and high pressure
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A Class of the Singularly Perturbed Boundary Value Problems for Elliptic Equation with a Super Surface of Turning Point in n-dimensional Space 被引量:6
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作者 王庚 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第1期41-46,共6页
In this paper, we study a class singular perturbed elliptic equation boundary value problem with a super surface of turning point in n-dimensional space by using the method of multiple scales and the comparison theore... In this paper, we study a class singular perturbed elliptic equation boundary value problem with a super surface of turning point in n-dimensional space by using the method of multiple scales and the comparison theorem. The uniformly valid asymptotic approxmations of solutions for the boundary value problem is constructed. 展开更多
关键词 singular perturbation turning point elliptic equation
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Invertibility of Infinite-Dimensional Hamiltonian Operators and Its Application to Plate Bending Equation 被引量:2
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作者 Alatancang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第3期562-566,共5页
The results of invertibility and spectrum for some different classes of infinite-dimensional Hayniltonian operators, after a brief classification by domains. are given. By the above results, the associated infinite-di... The results of invertibility and spectrum for some different classes of infinite-dimensional Hayniltonian operators, after a brief classification by domains. are given. By the above results, the associated infinite-dimensional Hamiltonian operator with simple supported rectangular plate is proved to be invertible. Furthermore, by a certain compactness, we find that the spectrum of this operator consists only of isolated eigenvalues with finite geometric multiplicity, which will play a significant role in finding the analytical and numerical solution based on Hamiltonian system for a class of plate bending equations. 展开更多
关键词 vplate bending equation INVERTIBILITY infinite-dimensional Hamiltonian operator
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Analysis of free vibration characteristic of steel-concrete composite box-girder considering shear lag and slip 被引量:9
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作者 周旺保 蒋丽忠 余志武 《Journal of Central South University》 SCIE EI CAS 2013年第9期2570-2577,共8页
Based on Hamilton principle,the governing differential equations and the corresponding boundary conditions of steel-concrete composite box girder with consideration of the shear lag effect meeting self equilibrated st... Based on Hamilton principle,the governing differential equations and the corresponding boundary conditions of steel-concrete composite box girder with consideration of the shear lag effect meeting self equilibrated stress,shear deformation,slip,as well as rotational inertia were induced.Therefore,natural frequency equations were obtained for the boundary types,such as simple support,cantilever,continuous girder and fixed support at two ends.The ANSYS finite element solutions were compared with the analytical solutions by calculation examples and the validity of the proposed approach was verified,which also shows the correctness of longitudinal warping displacement functions.Some meaningful conclusions for engineering design were obtained.The decrease extent of each order natural frequency of the steel-concrete composite box-girder is great under action of the shear lag effect.The shear-lag effect of steel-concrete composite box girder increases when frequency order rises,and increases while span-width ratio decreases.The proposed approach provides theoretical basis for further research of free vibration characteristics of steel-concrete composite box-girder. 展开更多
关键词 steel-concrete composite box-girder shear lag effect shear deformation SLIP free vibration
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Establishment and application of logging saturation interpretation equation in vuggy reservoirs 被引量:3
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作者 孙文杰 李宁 +2 位作者 武宏亮 王克文 张宫 《Applied Geophysics》 SCIE CSCD 2014年第3期257-268,350,共13页
Vuggy reservoirs are the most common, albeit important heterogeneous carbonate reservoirs in China. However, saturation calculations using logging data are not well developed, whereas Archie method is more common. In ... Vuggy reservoirs are the most common, albeit important heterogeneous carbonate reservoirs in China. However, saturation calculations using logging data are not well developed, whereas Archie method is more common. In this study, electrical conduction in a vuggy reservoir is theoretically analyzed to establish a new saturation equation for vuggy reservoirs. We found that vugs have a greater effect on saturation than resistivity, which causes inflection in the rock-electricity curve. Using single-variable exPeriments, we evaluated the effects of rug size, vug number, and vug distribution on the rock-electricity relation. Based on the general saturation model, a saturation equation for vuggy reservoirs is derived, and the physical significance of the equation parameters is discussed based on the seepage-electricity similarity. The equation parameters depend on the pore structure, and vugs and matrix pore size distribution. Furthermore, a method for calculating the equation parameters is proposed, which uses nuclear magnetic resonance (NMR) data to calculate the capillary pressure curve. Field application of the proposed equation and parameter derivation method shows good match between calculated and experimental results, with an average absolute error of 5.8%. 展开更多
关键词 Vuggy reservoir SATURATION general solution saturation equation capillary pressure capillary pressure curve NMR rock electricity.
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On Feasibility of Variable Separation Method Based on Hamiltonian System for a Class of Plate Bending Equations 被引量:5
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作者 额布日力吐 阿拉坦仓 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第3期569-574,共6页
The eigenfunction system of infinite-dimensional Hamiltonian operators appearing in the bending problem of rectangular plate with two opposites simply supported is studied. At first, the completeness of the extended e... The eigenfunction system of infinite-dimensional Hamiltonian operators appearing in the bending problem of rectangular plate with two opposites simply supported is studied. At first, the completeness of the extended eigenfunction system in the sense of Cauchy's principal value is proved. Then the incompleteness of the extended eigenfunction system in general sense is proved. So the completeness of the symplectic orthogonal system of the infinite-dimensional Hamiltonian operator of this kind of plate bending equation is proved. At last the general solution of the infinite dimensional Hamiltonian system is equivalent to the solution function system series expansion, so it gives to theoretical basis of the methods of separation of variables based on Hamiltonian system for this kind of equations. 展开更多
关键词 plate bending equation infinite-dimensioanl Hamiltonian operator eigenfunction system COMPLETENESS general solution
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New Multiple Soliton-like and Periodic Solutions for (2+l)-Dimensional Canonical Generalized KP Equation with Variable Coefficients 被引量:3
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作者 ZHANG Li-Hua LIU Xi-Qiang BAI Cheng-Lin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期793-798,共6页
In this paper, the generalized ranch function method is extended to (2+1)-dimensianal canonical generalized KP (CGKP) equation with variable coetfficients. Taking advantage of the Riccati equation, many explicit ... In this paper, the generalized ranch function method is extended to (2+1)-dimensianal canonical generalized KP (CGKP) equation with variable coetfficients. Taking advantage of the Riccati equation, many explicit exact solutions, which contain multiple soliton-like and periodic solutions, are obtained for the (2+1)-dimensional OGKP equation with variable coetffcients. 展开更多
关键词 (2+1)-dimensional canonical generalized (CGKP) equation with variable coefficients tanh function method Riccati equation soliton-like and periodic solutions
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Exact Solutions Expressible in Rational Formal Hyperbolic and Elliptic Functions for Nonlinear Differential-Difference Equation 被引量:3
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作者 BAI Cheng-Jie ZHAO Hong HAN Ji-Guang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期303-308,共6页
A new approach is presented by means of a new general ansitz and some relations among Jacobian elliptic functions, which enables one to construct more new exact solutions of nonlinear differential-difference equations... A new approach is presented by means of a new general ansitz and some relations among Jacobian elliptic functions, which enables one to construct more new exact solutions of nonlinear differential-difference equations. As an example, we apply this new method to Hybrid lattice, diseretized mKdV lattice, and modified Volterra lattice. As a result, many exact solutions expressible in rational formal hyperbolic and elliptic functions are conveniently obtained with the help of Maple. 展开更多
关键词 nonlinear differential-difference equations new approach exact solutions
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New Exact Travelling Wave and Periodic Solutions of Discrete Nonlinear Schroedinger Equation 被引量:2
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作者 YANGQin DAIChao-Qing ZHANGJie-Fang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期240-244,共5页
Some new exact travelling wave and period solutions of discrete nonlinearSchroedinger equation are found by using a hyperbolic tangent function approach, which was usuallypresented to find exact travelling wave soluti... Some new exact travelling wave and period solutions of discrete nonlinearSchroedinger equation are found by using a hyperbolic tangent function approach, which was usuallypresented to find exact travelling wave solutions of certain nonlinear partial differential models.Now we can further extend the new algorithm to other nonlinear differential-different models. 展开更多
关键词 discrete nonlinear Schroedinger equation hyperbolic tangent functionapproach solitary wave solution periodic wave solution
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Spontaneous combustion tendency of fresh and pre-oxidized sulfide ores 被引量:2
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作者 阳富强 吴超 李孜军 《Journal of Central South University》 SCIE EI CAS 2014年第2期715-719,共5页
Three representative sulfide ore samples were collected from typical metal mines,and their corresponding pre-oxidized products were obtained under nature environment.The thermal behaviors of each sample at heating rat... Three representative sulfide ore samples were collected from typical metal mines,and their corresponding pre-oxidized products were obtained under nature environment.The thermal behaviors of each sample at heating rates of 5,10,15 and 20 °C/min in air flow from ambient temperature to 800 °C were studied by simultaneous thermal analysis and the TG/DSC curves before and after the pre-oxidation were compared.By the peak temperature of DTG curves,the whole reaction process for each sample was divided into different stages,and the apparent activation energies were calculated by the Ozawa-Flynn-Wall method.The results show that the reaction process of each sample after pre-oxidation is more complex,with quicker reaction rates,fewer heat production quantities,and higher or lower ignition-points.The apparent activation energies decrease from 364.017-474.228 kJ/mol to 244.523- 333.161 kJ/mol.Therefore,sulfide ores are more susceptible to spontaneous combustion after the pre-oxidation. 展开更多
关键词 sulfide ores spontaneous combustion tendency apparent activation energy PRE-OXIDATION
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Bending analysis and control of rolled plate during snake hot rolling 被引量:6
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作者 张涛 吴运新 +2 位作者 龚海 郑细昭 蒋绍松 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第7期2463-2469,共7页
In order to study the bending behavior of aluminum alloy 7050 thick plate during snake hot rolling, several coupled thermo-mechanical finite element(FE) models were established. Effects of different initial thicknesse... In order to study the bending behavior of aluminum alloy 7050 thick plate during snake hot rolling, several coupled thermo-mechanical finite element(FE) models were established. Effects of different initial thicknesses, pass reductions, speed ratios and offset distances on the bending value of the plate were analyzed. ‘Quasi smooth plate' and optimum offset distance were defined and quasi smooth plate could be acquired by adjusting offset distance, and then bending control equation was fitted. The results show that bending value of the plate as well as the extent of the increase grows with the increase of pass reduction and decrease of initial thickness; the bending value firstly increases and then keeps steady with the ascending speed ratio; the bending value can be reduced by enlarging the offset distance. The optimum offset distance varies for different rolling parameters and it is augmented with the increase of pass reduction and speed ratio and the decrease of initial thickness. A proper offset distance for different rolling parameters can be calculated by the bending control equation and this equation can be a guidance to acquire a quasi smooth plate. The FEM results agree well with experimental results. 展开更多
关键词 snake hot rolling bending analysis quasi smooth plate optimum offset distance bending control equation
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