Abstract: For solving the actual problem of forecasting the rock masses falling accurately, grey-catasthphoe model to forecast the stope stability is estabished based on the non-linear theory, and a computer program flow chart is also presented. In the end, the model is proved to be feasible by a gold mine monitoring results.
Abstract: Fractal theory is a new method to apply in time series analysis, but how to discriminate fractal time series from non-fractal time series is ambiguous. Several Parame-ters, such as Poincare map, Lyapunov exponent, correlation dimension, power spectrum density and Hunt exponent, are used to recognize if the time series are fractals. The relia-bilities of the parameters used above arc compared. If the dynamic system is known, it's fit to use the Poincare map and Lyapunov exponent; while if the dynamic system is unknown, it, s fit to use the power spectrum density and Hurst exponent. At last, the range of fractals applying in time series analysis is sketched.
Abstract: The vibrations of diesel engines high pressure lines during injection time contains much information of the fuel system condition,the research shows that the signal has fractal characteristics, i. e. self-similar stochastic structure within the data. It belongs to 1/f noise family. The information of the signal can be concentrated in one parameter, Hurst Exponent or Power Spectrum Density (PSD) exponent. By analyzing the sensitivity of the PSD exponent in variant conditions of the fuel system, a non-intrusive fault diagnosis method to diesel engines is supplied.
Abstract: The study on acoustic emission (AE) of concrete material is combined to the studies on mechanical process and fracture damage, and the conception of AE process is put forward. On this basis a quatitative function for analysing the self-similarity of AE process has been developed.The experimental results show that the values of the self-simi-larity function of the AE process in concrete material vary with the state state during uniaxial compression.
Abstract: On the basis of the ladle's thermal circulation, a heat transfer mathematical model of melt steel was established, and was applied to the respective metallurgical unit in RH-CAS. OB combined process at Wuhan Iron and Steel Company. The main influential factors of the melt steel temperature in the CAS-OB process was analyzed. The temperature system in the RH-CAS.OB process was calculated and optimized on the basis of the new computer model. And the results provide the theoretical instructions to practice production.
Abstract: Inclusions in Centrifugal Induction Electroslag Castings were qualitatively and quantitatively analyzed. The influences of the centrifugal machine rotational speed on the inclusions pattern and distribution were discussed. The largest size of the inclusions in the castings was also calculated. The results show that sulphide inclusions are even distributed and the content is low, while the content of oxide inclusions is high and there are some differences along radial direction. With the increase of the centrifugal machine rotational speed, the ratio of round inclusions increases and the ratio of sharp inclusions decreases. The largest diameter of the inclusions in the castings is only 6.6μm.
Abstract: A new mineral transducer for monitoring wire-rope tension of multiple-rope friction winder was presented. The pressure elastic membrane of round plane was adopted as the output of differential capacitance signal in variable plate distance. The integrated construction of elastic sensing elements and transformation circuits was designed and manufactured as a totally enclosed transducer, which has good vibration and shock resistance, and is suitable for the severe environment underground.
Abstract: A closed magnetic circuit was designed. In the circuit of speaking system, NdFeB and A3 steel were served as hard magnetic material and conducting material respectively, moreover, it has beed studied that the conducting properties of soft magnetic material of A3 low-carbon steel in different thickness. The magnetic density in the opening of the circuit was researched in different thickness of NdFeB. The experi-ment revealed that the width of opening, conducting material and hard material have much effect on the magnetic density in the opening of circuit.
Abstract: Base on the analysis of heat balance of LF-VD-CC process, the liquid steel temperature control model has been developed. The results of simulated calculation melt temperature in LF-VD-CC process show that the liquid steel temperature control model bas high hitting ratio for predicting the process temperature.
Abstract: Spray forming technique has been applied to prepare 18Ni(250) maraging steel+10%Al2O3 particulate reinforced metal matrix composite. The spray deposited preform shows high density and favourite microstructures such as homogeneous distribution of the reinforcement particulates and free from interface reaction. Compared with the matrix 18Ni maraging steeh the composite demonstrated an accelerated aging behaviour. After heat treatment, the composite material shows a tensile strength near the matrix steel, with much improved wear resistance. Nanoindentation investigation of the aging process of the composite material shows that there exists a sharp distribution of elastic modulus and microhardness around Al2O3 particulates, which can be attributed to the distribution of precipitate caused by the thermal misfit dislocation distributions.
Abstract: A composite. pitot tube was used to measure the flow field of the atomdzing gas during the spray deposition process and numerical simulation of the flow field by neural network method was also adopted. Finally a precise relationship between the atomizing gas pressure and axial velocity in the flow field was acquired and the gas Dow field under different atomizing pressure was predicted.
Abstract: Magnetic regenerators Er(Ni1-xCox)(x-0,0.1,0.2) have been studied Curie temperature of Er(Ni1-xCox)(x-0,0.1,0.2) decreases to the temperature range below 10 K by replacing Co with Ni partially. Magnetic regenerators Er(Ni1-xCox)(x-0,0.1,0.2) have larger specific heats than Pb and other Er-Ni magnetic regenerators. It is shown that effective value J of total angular momentum of Er+3 ion is about 3/2 from the curves of the specific heats.
Abstract: The behavior of second-phase particles in IF steels during annealing prcx:ess was investigated in detail. The results show that the size* shape and dispersion of second-phase particles forming before annealing, such as TiC, change differently in batch annealing (BA) in comparison with continuous annealing (CA), and two kinds of second-phase particles not existing before annealing here, FeTiP and (Ti, Mn)S, precipitate in BA but not in CA. It has been rarely reported so far that FeTiP precipitates and Mn exists in (Ti, Mn)S form in IF steels with low P (≤ 0.01%) and low Mn (<0.2%) during BA. In addition, the dispersion, the phase structure of the two phases were studied, and their potential contribution to the production of IF steels through BA is also discussed.
Abstract: The dynamic recrystallization and flow stress mcxlels of Q235 (plain carbon steel) were established by regression with experiment data, and the flow stress model was used for work hardening zone,the results calculated by the models agreed with those measured results. The condition of upsetting test was:temperature,900~1150℃ forming rate,0.01~1.0s-1; initial grain size,48~85 μm.
Abstract: The concept of Periodic Asynchronous Rolling is put forward for the first time and the main cause leading to random parallel waves across the width on jobbing sheet surface on the roll is analyzed. Then improvement measures and adjustments on the rolling mill have been taken. The surface quality of products is obviously improved.
The fractal dimension was applied to describe the non-linear behavior of rolling bearing in different fault conditions and to classify the state of rolling bearing. The experiment results show that the fractal dimension of the vibration signal of rolling bearing is different in different fault conditions and can be used as the characteristics for recognizing the rolling bearings fault.
Abstract: The effect of thermal couple on the thermal conductivity measurement by cross hot-wire method was theoretically analyzed, a practical correction formula for the temperature rise of wire was presented. The thermal conductivity of nontransparent solid materials such as diatomaceous brick, light clay brick and building brick were measured, and the experimental results conform with the data of heat-plane method and some references. Moreover, the thermal conductivity of one especial glass sample-glass K9 is reported in the temperature range 300~1300 K.
Abstract: A mathematical model of heat and mass transfer during the granular materials drying has been presented. Both the variation of the materials' temperature and moisture content can be predicted. The model prediction agrees with the experiment data.
Abstract: The solving strategy of multi-expert system based on D-S evidence theory was studied.This strategy can gradully reduce the hypothesis sets and approach the truth with the accumulation of evidences,which make the result of decision more all-around and more scientific. The simulation of the diagnose of abnomal pheonmena in heating furnace is carried on the basis of the theory.The result is satisfactory.
Abstract: Some problems of model concept, model structure and model management in DSSG of Decision Support System development tool are discussed. The concept of atomic model and composite model is introduced in order to use DSSG completely. A design method and design of structured-model language SML are presented.
Abstract: The method of self-learning motion control of spinning machine and its construction of control are presented. The problem, which must be resolved in use for spinningg machine replaced NC technique, is discussed and the accomplishing way is given.
Abstract: The measuring principle and experiment of Laser Ultrasonic Pulse by Laser Heterodyne Interfermetric Method is described. The effect of collimation angle of signal light、reference light upon S/N radio is discussed, and the effect of incidence of signal light upon bean spliter on heterodyne signal intensity is discussed too. In order to increase the detective signal intensity, the method of heterodyne interferomtric conjugate output is developed.
Monthly, started in 1955 Supervising institution：Ministry of Education Sponsoring Institution：University of Science and Technology Beijing Editorial office：Editorial Department of Chinese Journal of Engineering Publisher：Science Press Chairperson：Ren-shu Yang Editor-in-Chief：Ai-xiang Wu ISSN 2095-9389CN 2095-9389
