Papers by Author: Jun Ruo Chen

Abstract: At present, study on the non-asbestos gasket materials is the hotspot research in static sealing field. The non-asbestos sealing gaskets research and development has made great strides into the practical phase. Formula is an important factor of material, which determines performance of material. In order to obtain well performance, it is needed to optimization formula to get optimal formula that not only improve performance of non-asbestos gasket, but also reduce development time accordingly reduce cost of non-asbestos gasket. Classification of raw materials can be transformed into a mathematical clustering problem. It means that according to some algorithm, there will be some sort of input values of similar links together. Many neural networks were widely used in the classification of different materials. A method of classification by using neural network to the known 15 kinds of the non-asbestos gaskets of formula data was proposed in this paper. By using the PNN (probabilistic neural network), LVQ(Learning Vector Quantization) neural network and SOM (Self-Organizing Feature Map) neural network respectively to classify the non-asbestos gaskets to find a suitable method in the classification of non-asbestos gaskets formula. The results indicated that PNN neural network and LVQ neural network method based on the data that provided in the paper both can effectively classify, while SOM neural network can not classify them ideally, thus it provides a new theoretical basis for the classification of the non-asbestos gaskets.

Abstract: The unsaturated biological material is divided into the wetting phase and the non-wetting phase, the diffusion of which has the characterization of fractal. In this study, we developed a simple wetting region model to calculate the local moisture content using the box-counting method during the drying process. A new constitutive relationship was derived to determine the unsaturated porous biological material’s shrinkage with the local moisture content and the fractal dimension of the wetting phase. The volume change was linearly correlated with local saturation with larger correlation coefficient, so the new mathematical model is more accurate than others.

Abstract: Single machine scheduling problem with setup times is proved to be an NP-hard problems, and its complexity is equivalent to the traveling salesman problem (TSP) of n cites. Integrating the advantages of simulation and genetic algorithm (GA), this paper proposes a GA based on simulation to solve this NP-hard problem. Then, it introduces how to build the simulation model and how to design chromosome coding and selection, crossover and mutation operators of GA for this special scheduling problem in details. An experiment has been carried out and the result proves that the method is feasible and should be adopted.

Abstract: In this paper, based on the analysis of coupled action of temperature, phase transformation and stress, the phase transformation condition and equation related to the thermal physical properties are discussed, and the transient temperature distribution of a Cr12 steel cylinder workpiece during gas quenching was obtained by solving the governing equations with a nonlinear boundary. According to the theories of thermal non-elasticity, computational mechanics and phase transformation, a new constitutive equation considering effects of phase transformation with a nonlinear surface heat transfer coefficient is proposed and is solved by means of finite element method (FEM). The thermal stress field is obtained and a way of simulating the technology of the heat treatment by computer is explored.

Abstract: A new nonlinear constructive model for description of temperature field of carbon steel axisymmetric body during the magnetic field quenching has been established based on thermo-magnetic coupling analysis. Using the model and finite element method, a numerical calculation program is developed with Microsoft FORTRAN 5.0, and cooling curves of center in a carbon steel sample of 30mm in diameter and 60mm in length during magnetic field quenching and common quenching are calculated and tested. Results showed that calculated cooling curves is accordant with corresponded tested cooling curves very well, and the calculated accuracy of temperature field during magnetic field quenching based on the new model is satisfactory.