CHARACTERISTICS OF SUBDIFFERENTIALS OF FUNCTIONS

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CHARACTERIZATION OF POWDER FLOWABILITY USING MEASUREMENT OF ANGLE OF REPOSE

In response to the need in industry for a quick and reproducible method of measuring the flowability of powders in processes involving transport and storage, the apparently simple idea of measuring angle of repose has been revived. The simple tester first used has evolved over a number of years into the present version which is shown to be capable of handling quite small samples of powders that are even slightly cohesive. Experimental data are presented and results shown to compare consistently with the better known Hausner ratio.     

TORSIONAL RIGIDITY OF SHELLS OF REVOLUTION

In this paper,the general equations of equilibrium for axisymmetrical deformationincluding the torsional deformation of revolutional shells are derived.It is shown that theshearing stress distribution due to torsion is independent of other stress componentsincluding those of membrane stress and bending stress.In this paper,the torsional deformation is considered to be represented by membraneaction only,and also by the combined action of bending membrane deformation.It is shownthat the main contribution of torsional rigidity is that related to membrane action.     

THE THEORY OF SIMILARITY AND THE PROFILE OF VERTICAL DISTRIBUTION OF CONCENTRATION OF SAND PARTICLES

In this article,we treat the problem of two-dimensionaluniform steady channel flow of turbid water with theory ofsimilarity.Under the condition of similarity of turbulentfluctuation velocity and fluctuation of concentration ofsand particles,we obtain the profile of the vertical dis-tribution of concentration of sand particles.This profileof vertical distribution of concentration of sand particlesis slightly different from that obtained by diffusion theory,and departs from that obtained by gravitational theory.     

ANALYSIS OF THE MOTION OF A GYRO-THEODOLITE

With the method of analytical mechanics,this paper studies the motions of a gyro-theodolite under the action of (1) the torque of gravity only,(2)the torque applied by theband suspension.(3)the torque of the band suspension with air damping considered,theequations of motion are then established and their solutions are found.Furthermore,analysis of the law of motion and the behaviour of gyro-theodolite during the orientation ismade.     

THEORY OF ELASTICITY OF AN ANISOTROPIC BODY FOR THE BENDING OF BEAMS

A theory of elasticity for the bending of orthogonal anisotropic beams has been developed by analogy with the special case, which can be obtained by applying the theory of elasticity for bending of transversely isotropic plates to the problems of two deminsions. In this paper, we present a method to solve the problems of bending of orthogonal anisotropic beams and a new theory of the deep-beam whose ratio of depth to length is larger. It is pointed out that Reissner's theory to account for the effect of transverse shear deformation is not very approximate in the components of stress,     

APPLICATION 0F THE THEORY OF BRANCHING OF SOLUTIONS OF NONLINEAR EQUATIONS IN THE ESTIMATION OF POLE PERTURBANCE OF LINEAR CLOSED-LOOP SYSTEMS

When the state and input matrices of a multivariable lineartime-invariant system are perturbed.the problem of the es-timation of pole perturbance of closed-loop system is con-sidered by making use of the theory of branching of solutionsfor nonlinear equations.     

BLOW-UP OF SOLUTIONS OF NONLINEAR PSEUDO-HYPERBOLIC EQUATIONS OF GENERALIZED NERVE CONDUCTION TYPE

This paper deals with the two type of mixed problems with respect to Neumannboundary and Dirichlet boundary for nonlinear pseudo-hyperbolic equations of generalizednerve conduction typeu_1-△u_1=F(x,t,u,(?)u,u_t,(?)i_t)when the nonlinear part F(x.t,u,(?)u,u_t,(?)u_t)and the initial values satisfy someconditions,the blow-up properties of the solutions are obtained.     

COMPUTER SIMULATION OF THE MOTION OF THE BULLET BELT OF AIRPLANE GUN

ＣＯＭＰＵＴＥＲＳＩＭＵＬＡＴＩＯＮＯＦＴＨＥＭＯＴＩＯＮＯＦＴＨＥＢＵＬＬＥＴＢＥＬＴＯＦＡＩＲＰＬＡＮＥＧＵＮＺｈａｎｇＤｉｎｇｇｕｏ（章定国）（ＲｅｃｅｉｖｅｄＭａｒｃｈ１７，１９９５；ＣｏｍｍｕｎｉｃａｔｅｄｂｙＷｕＲｕｉｆｅｎｇ）Ａｂｓｔｒ...     

EFFECT OF POLYETHYLENEIMINE ON THE PROPERTIES OF CONCENTRATED SUSPENSIONS OF TITANIUM DIOXIDE MICROBEADS

The effect of polyethyleneimine (PEI) concentration on the properties of titanium dioxide (TiO2) suspensions is studied with or without the addition of an electrolyte (barium acetate). Measurements of the apparent viscosity and the stability of TiO2 suspensions showed that PEI is an effective dispersant for TiO2 particles in suspension in the absence of an electrolyte, not only reducing the viscosity of the suspension but also increasing its stability. In the presence of an electrolyte, however, small quantities of polyethyleneimine could neither disperse the TiO2 particles nor de-crease the viscosity of the TiO2 suspensions; only PEI concentrations beyond saturation adsorption could perceptively improve the stabilitv of TiO2 suspensions.     

ON GRAMMATICAL COMPLEXITY OF A CLASS OF ATTRACTORS

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STABILITY OF SYSTEM OF TWO-DIMENSIONAL NON-HYDROSTATIC REVOLVING FLUIDS

Applying the theory of stratification, it is proved that the system of the two-dimensional non-hydrostatic revolving fluids is unstable in the two-order continuous function class. The construction of solution space is given and the solution approach is offered. The sufficient and necessary conditions of the existence of formal solutions are expressed for some typical initial and boundary value problems and the calculating formulae to formal solutions are presented in detail.     

SUGGESTION OF A NEW DEFINITION OF ANGULAR STRAIN

A new definition of angular strain is put forward in this paper. Analogous to the definition of linear strain, angular strain is also defined as a rate of change (of angular displacement). It is verified that the new definition is equivalent to the original besides being more convenient for geometrical interpretations. Using this new definition we have deduced the transformation formulas for rotation of coordinate axes, established the strain tensor and proved the Hooke's law for shearing.     

SIMPLE MEASUREMENT OF RESTITUTION COEFFICIENT OF IRREGULAR PARTICLES

Restitution is an important physical and mechanical property of granular materials. However, measuring its values in instantaneous collisions between particles is very difficult, especially for ore particles of irregular shapes. In this paper, restitution is measured indirectly and statistically with two cameras recording from different angles the trajectories of the ore particles rebounding from a steel plate. The momenta of the particles prior to and after the collision are calculated from the trajectories to give the restitutions of these collisions. The restitution between ore particles is then derived from the restitution of a steel ball with the steel plate measured in the same way. The approach has been proved to be practical and reliable for a variety of ore particles with moderate restitutions.     

METHOD OF MOMENT EXCITATION IN TESTING OF STRUCTURES

The method of the moment excitation in the studies of the structure-borne sound using a moment actuator is introduced.Some design considerations for themoment actuator are presented.A standard mechanical system is established to calibratethe performance of the moment actuator.The frequency and mechanical powerperformances of the actuator are discussed.     

APPLICATION OF THE METHOD OF THE RECIPROCAL THEOREM TO FINDING DISPLACEMENT SOLUTIONS OF CUBES

In this paper the method of reciprocal theorem is extended to find solutions of three-Dproblems of elasticity.First we give the basic solution of the cube with six surfaces fixed as the basic systemand then using the reciprocal theorem between the basic system acted on by unitconcentrated loads and the actnal system with Precribed surface displacements,we finddisplacement solution of the actual system.     

APPLICATION OF THE FINITE PART OF A DIVERGENT INTEGRAL IN THE THEORY OF ELASTICITY

Using the finite part of a divergent integral,we transform Kelyin’s solutions,Boussinesq’s solutions and Mindlin’s solutions in the three-dimensional theory of elasticityinto corresponding solutions in the two-dimensional theory.Besides,its application in planeproblems is also given.     

THE EQUATIONS OF MOTION OF A SYSTEM UNDER THE ACTION OF THE IMPULSIVE CONSTRAINTS

In order to solve the problem of motion for the system withn degrees offreedom under the action of p impulsive constraints, we must solve the simultaneous equations consisting of n+p equations. In this paper, it has been shown that the undetermined multipliers in the equations of impact can be cancelled for the cases of both the generalized coordinates and the quasi-coordinates. Thus there are only n-p equations of impact. Combining these equations with p impulsive constraint equations, we have simultaneous equations consisting of n equations. Therefore, only n equations are necessary to solve the problem of impact for the system subjected to impulsive constraints. The method proposed in this paper is simpler than ordinary methods.     

THEOREM OF THE UNIQUENESS OF DISPLACEMENT AND STRESS FIELDS OF LINE-LOADED INTEGRAL EQUATION METHOD

According to Fredholm＇s theorem,this paper proves that due to the virtualfundaemenial loads which satisfy the boundary conditions and being distributed outside theelastic body occupied region the displacement and stress fields in the elastic body occupiedregion are unique.This theorem forms a theoretical basis of the applications of theline-loaded integral equation method.