A constant volume combustion test system is designed and developed,which is a simulation test device for the analysis of natural gas engine combustion process.This system can realize independent control of almost all of the parameters of combustion process,and possess better applicable value.

The factors affecting tangential resistance between coal and working parts,such as water content of coal and normal pressure,are analyzed.Results show that there is obvious interaction between water content of coal and normal pressure when there is affecting tangential resistance.For lower normal pressure,tangential resistance increases with the water content.For higher normal pressure,the relationship between tangential resistance and water content is consistent with quadratic parabola.Surface electroosmosis method can reduce coal tangential resistance,but the pole distribution affects the result of reducing resistance.When the area rate between positive plate and negative pate is 1:3,the maximum of reduction for tangential force is 8.8%.

A new technology is put forward for vibration drilling under changed parameters of three cutting regions for machining micro holes.A new method is probed with which optimal vibration parameters of the stages are determined by non linear regression.Present investigation shows that the new method for vibration drilling,in which vibration parameters are changed with the optimal parameters of the stages,is an effective way to decrease error of drilling micro holes.

The infinite unit model of spot welding nugget thermal field is set up with 65 Mn steel.The effect of contact resistance,liquid nugget temperature and phase transformation latent heat on spot welding nugget thermal field is fully considered.This model can be used to study thermal process of spring steel spot welding systematically,providing theoretical basis for designing spot welding technology parameters and numerical prediction of microstructure and properties of spring steel spot welding.Experiments show the similar results which are matched between the theoretical calculation and the experiments.

With upper bound method and least energy principle,the conditions are established of drawing and breaking workpiece with cross wedge rolling technique to form axial symmetry spare parts.The figure of working limits is obtained about forming axial symmetry spare parts with cross wedge rolling technique by combining study results in this article with the ones in documents [1～3].

The paper analyses the forming process of eccentric shaft with cross wedge rolling.The authors show the special forming method of eccentric shaft,take the brake shoe shaft of CA141 truck as example and make an experiment on it.The research keeps up with standards of assembling and is put into production.The achievements have practical significance to extend the area of cross wedge rolling forming to engineering use.

The paper presents an optimal control scheme based on moving optimization principle of model predictive control for linear system with constraints.The scheme with infinite prediction horizon and finite control horizon can guarantee nominal asymptotic closed loop stability.The simulation results applied to a laboratory setup Three-Tank-System demonstrate effectiveness of the proposed scheme.

The paper mainly focuses on the packet scheduling algorithm of GPRS(General Packet Radio Service).The authors put forward QoS standard and delay normalizations of GPRS,then elicit some principles of packet scheduling algorithm of GPRS and present a packet scheduling algorithm based on delay requirement.By simulation,the research finds out that the new algorithm is to meet the delay requirements at much higher resource utilization and little complexity compared to the other alternatives.

This paper presents a kind of method,which can measure consistency of transparent liguid.By measuring the change of ultrasonic grating spacing,which is caused by the change of consistency,the function about them will be regressed and the consistency will be measured.The receiver of the system is CCD.In definite range,the measuring accuracy will not exceed 0.4%.

This paper presents the concept of order random variable for the first time,and obtains the probability density function of X(k).

This paper has formulated a kind of nonconnected graph C₄∪K_m,n ,and proved that the graph C₄∪K_m,n is a k graceful graph when k>1(k∈N) ,and that the graph is a ( k,d )arithmetic graph when k>[(n-1)m+1]d+1(d>1 and m,n,d∈N) .Thus,the research has reached some conclusions about reference[7].

The existence of positive entire solutions on R^N,N≥3 is established for a singular nonlinear elliptic equation by utilizing the Schauder fixed point theorem.The research generalizes the results of paper[1].

An improved inverse power method for calculating the eigenpair of a structure is presented based on the combination of the inverse power method and topological variation method of structures.

In this paper,linear expansion coefficient and residual stress of a new type of material—carbon plastic compound material are determined with the theory and technique of strain electric measurement.Some important conclusions are achieved.The results provide scientific basis for the development and application of carbon-plastic compound materials.

In this paper,a new all solid state quinine selective electrode based on quinine and bismuth iodide association complex is reported for the first time.The electrode shows nernst response for quinine with a slope of 40 mV/pC over the concentration range of 1.0×10^-1～1.0×10^-5 mol/L.The detection limit is 2.5×10^-6 mol/L.While pH is at 3.08～6.10,the change of the electrode response does not exceed ±1mV.The electrode possesses fast response and good reproductibility.The procedures of this method are simple and the results obtained agree with those of pharmacopoeia.

Recently two types of discontinuities have been observed in the structural simulations of proximal femur.The first type called near field behavior appears in areas near distributed load application and is characterized by a checker board pattern of density.The second type of discontinuity called far field behavior appears remote from the load application and is characterized by strut or column like regions of elements.In fact,the far field discontinuity is an accurate representation of bone physiology and morphology.On the other hand,the near field discontinuity is a false representation of bone structure and violates the continuum assumption underlying the finite element method.The objective of this article is to devolop structural simulation of proximal femur as a self organizatinal control process by M.G.Mullender(1993),with the finite element method and bone self-optimization theory.The end configuration not only eliminates the checker-board density distribution typical of the early models,but also predicts a reasonably accurate density distribution.

In this paper,the frontier theory of evaporation is applied to the study of the process of heat and mass transfer during drying paddy.The Galerkin weight residual method of finite element method is used to solve the equation of coupled heat and mass transfer with moving evaporation front.Computer simulates the change rate of rice taste during paddy drying.The rice taste value of different paddy drying technology is predicted.

Wet coal dusts adhesion to tub has not been solved properly.Based on investigations for tub,the authors make an exploration and analysis for adhesion phenomenon,adhesion law and adhesion mechanism,present a solution plan and make a calculation for the economic returns.

While hydraulic coupling for changing speed is the control element,the dynamic property influences the dynamic process of all the system.For example,the slay mud pump liquid level control system by hydraulic coupling,becomes bad.This paper puts forward the MRAC-PID control method which simpifies the design of conventional model reference with the adaptive control system.The control method has been testified possible and practical by a lot of emulation and imitation experiments.

In this paper,the static shape control of the flexible intelligent thin shell structure is derived by the intelligent thin shell element of Ref.[5].Finally,a numerical example of a paraboloid antenna is given.

The experimental analysis of 6102 gasoline engine continuous running after cutting off ignition is performed by means of AVL is digital analyzer 657.The basic characteristic and principle of gasoline engine continuous running is expounded,and the way of preventing gasoline engine from continuous running is proposed.

In this article,the authors point out that research the resources characteristics of research and development process will assure the success of the reengineering.The main resources in research and development process are human resources,capital,knowledge and information technology.After clarifying the sort of the resources,the authors go deep into the characteristics of resources in research and development process.

Infrasound affecting humans' physiology has been researched in the last twenty years both in China and abroad and put in order.The results show that if audition threshold curve corresponding frequency dot is above 15～20dB, the infrasound affects many humans’ physiology functions.

The research state of the on line optimal control on spindle speed is discussed.The advantages and disadvantages of the studies in the research area are analyzed and the prediction is made.