COMPLICATED MOTION OF DEFINITE DUFFING SYSTEM WOTH CONSTRAINT

The definite Duffing system with constraint has been discussed,and the numerical simulations of some typical cases have been given. It is found that the motion phenomena in the definite Duffing system with constraint are more complex than those in the normal Duffing system without constraint.     

THE CALCULATION OF FLOW USING SEMI-IMPLICIT METHOD FOR PRESSURE-LINKED EQUATIONS

This paper briefly introduces Patankar-Spalding Method, which is systematical, active and widely applicable in numerical heat transfer and fluid flow. The corresponding dependent variables, diffusivities and source terms for the general differential equations under all circumstances are explained. By using this method the calculation of two-dimentional Poiseuiue Flow and Couette Flow compared with exact solutions are proved to be high precision. with two-dimentional path-flow in the heat convertor intersification devices as an example, the tilted method is used with FORTRAN 77 programming, and the calculation is done on a SIEMENS 7570c minicomputer.     

ALGORITHM AND CONVERGENCE OF TWO-STAGE ITERATIVE PROCEDURE FOR SOLVING SYSTEMS OF LINEAR EQUATIONS

This papr discusses algorithm and convergence of twostage iteratve procedure for solving systems of symmetric positive definite linear equation Ax=b. On the basis of nature splitting of A, this algorithm makes two-step linear iterative procedure (named outer iteration) and makes convergent inner iteraton of any kind.They generate a sequence of approximations {x_h} w.hich converges to the solution Ax=b quickly. This paper also proves is convergene and gives the estimation of error.     

THE ALGEBRATIC CRITERION OF THE UNCONDITIONAL STABILITY OF THE THIRD-ORDER LINEAR RETARDED DIFFERENTIAL DIFFERENCE EQUATIONS

The sufficient and necessary conditions of the unconditional stability of the third-order linear retarded differential-difference equations with constant coefficients are given. The conditions are brief and practical algebratic criterion.     

THE UNIQUENESS OF FLAT SOLUTION ON SOME FUCHSIAN EQUATIONS

This paper studies the uniqueness of flat solutions on some Fuchsian equations. First, Carleman's estimate for a first order P_sDO is proved, then the uniqueness of the solution of first and second order Fuchsian equations are proved by classic method. Finaly, the uniqueness of t-involutive equations is obtained.     

THE ANALYTICAL EQUATIONS OF HYDRO-THERMAL POWER SYSTEM ECONOMIC DISPATCH

The paper developes the analytical equations of the power economic dispatch by using the modified coordination equation, it also developes the explicit functional relation between the hydro-coal conversion factor and the daily water consumption. Using these expressions,the calculating amount of the hydro-thermal system economic dispatch is greatly reduced and the convergency is much better. Finally a numerical example is given to show these advantages.     

中国南亚热带的多熟耕作制及其新发展

本文在分析中国南亚热带自然条件和经济特点的基础上,指出这一地带的多熟耕作制的若干主要类型是:(1)以水稻为主的多熟制;(2)稻田旱作物多熟制;(3)农牧渔相结合的复合多熟制;(4)旱地耕作制。另外,还探讨了南亚热带多熟制的资源利用及其综合评价。最后,作者强调指出:在调整农业生产结构和作物布局中,为了兼(?)经济、社会、生态     

THE RHEOLOGICAL PROPERTIES AND CLASSIFICATION AND CONSTITUTIVE EQUATIONS OF HUMAN BILE

Rheological properties of hepatic bile and gallbladder bile have been studied systematically in this paper. 223 specimens of hepatic bile and 39 specimens of gallbladder bile,including the acute,chronic,cholestatic,non-cholestatic cholecystitis and cholelithiasis,are collected. The experimental results have showed that the apparent viscosity of hepatic bile decreases rapidly and becomes a constant eventually as the imflammation of biliary system declines,and that the gallbladder bile is a kind of non-newtonian liquids and its rheological properties are closely related with the pathological conditions. According to its physical characteristics,gallbladder bile can be classified into three groups. The modified Maxwell' s viscoelastical model for gallbladder bile has been proposed on the basis of the experiments and analyses.     

THE MINIMAL PERIODIC SOLUTIONS OF SYMMETRICAL AUTONOMOUS SUBQUADRATIC CONSERVATIVE SYSTEMS

The existence of the minimal periodic solutions of the non-constant of a class of symmetrical autonomous subquadratic second order Hamiltonian systems is studied with minimization.     

ON THE PROBLEM OF SWITCHING CONDITIONS FOR A KIND OF MINIMUM-TIME CONTROL SYSTEMS

The paper provides a detailed study of switching conditions of minimum-time control systems based on application in engineering. By analysis in theory and experiment, the authors deduce a set of switching conditions with state and control variabes inequality constraints, the variations of system parameters and the time-delay of computer in real time control. As an example, a DC motor speed control system is considered. By digital simulation and physical experiments,these conditions proved to be correct. The method in this paper is also suitable for other control systems using compound control algorithm.     

AN OPTIMIZATION METHOD FOR SOLVING THE BOUNDARY WALUE QUESTION OF DIFFERENTIAL EQUATIONS

This paper presents an optimization method for solving the boundary value question of a differential equation on the basis of the trial-and-error method and the optimization method. As compared with the differential method, this method has some advantages such as quiker velocity at count, higher precision(especially at the boundary points) and can be widely used.     

玉米苗期根系生态生理研究

在利用水培研究玉米苗期根系生态的基础上,着重研究了苗期根系生态显著不同的白玉米232和黄火燥1048二个品种的根系生态生理。结果看出,黄火燥1048根系分布深,在淹水情况下根系受抑制轻,对³²P 吸收能力强。两个品种胚根中游离氨基酸的种类和含量也不同;两个品种都表现出地上部氨基酸含量和种类与根系不同。     

THE MONTE-CARLO METHOD FOR RELIABILITY EVALUATION OF LARGE SCALE COMPOSITE GENERETION-TRANSMISSION SYSTEMS

The paper presents a Monte-carlo method for reliability evaluation of large scale composite generation transmission systems. The method, which possesses coputational rapidity and sufficient accuracy,is based on combining the dispersed sampling techique with the analysis approach and the optimization model of power not supplied. Because the amount of calculation increases only linearly with, the number of elements, it is specially sui- table for large scale systems. The Monte-carlo sampling draws more near the real situation than determinate state enumeration in simulating occurrence of power system outages. Also, the method can be easily generalized to involve multi-states of elements, multi-levels and stochastic distribution of loads. The results of IEEE-RTS, as example, are given and compared with ones obtained by using the other two methods.     

THE DIRECTING MECHANISM OF V-NOTCHF WITHJN V-NOTCHJNG BLASTING

Based on the blasting theory and "Fracture Mechanics " , the directing effect mechanism of V-netch in V-rotching blasting is studied and the positive splitting and directional explanding of crack within V-notching blasting and the priority of crack's expanding in the V-notch axle-plane etc are expounded. It's just these fracture characteristics mentioned above that ensure the fine control of the cracking plane.     

AN A. C. LOAD FLOW ANALYSIS OF THE RELIABILITY EVALVATION OF COMPOSITE GENERATION AND TRANSMISSION SYSTEMS

An A. C. load flow analysis of the reliability evaluation of composite generation and transmission systems is presented on the basis of a fast outage simulation algorithm and an optimal model of active and reactive power adjustment after outage contingencies. The information of the first -level outage events is utilized for simulating higher -level outage events in the fast outage simulation algorithm ; the optimal model is satisfactory in speed and accuracy with the application of concentric relaxation and linear increment constraint on the comprehensive adjustment of active and reactive power. As an example. the IEEE Reliability Test System is tested and the results show that the method is accurate and well-matched in speed with the method studied by R. Bllinton, et al.     

AN INVESTIGATION ON THE MULTI-ARCH STRUCTURE OF A STRATA AROUND A STOPE

This paper analysis the mechanical process with the photoelast-ic model test ane the finite element method, and presents the basic cause of existing different pressure and different transfiguration in the strata around a stope.