Advanced Materials Research Vols. 171-172

Abstract: In order to quest an effective approach for predicate the rheologic deformation of sandstone based on some experimental data, an improved approaching model of RBF neural network was set up. The results show, the training time of improved RBF neural network is only about 10 percent of that of the BP neural network; the improved RBF neural network has a high predicating accuracy, the average relative predication error is only 7.9%. It has a reference value for the similar rock mechanics problem.

Abstract: This article analyzes the characteristics of underground coal mine production process, and compares underground coal mine production process with discrete type and continuous type production processes. On this basis, it investigates the construction and implementation countermeasures on underground coal mine information system.

Abstract: Chaos computing is a new circuit design scheme of using chaos computing units to achieve reconfigurable logic gates. The computing unit can function as different kinds of logic gates by changing external parameters. In this paper, the possibilities of expanding the function of a chaotic NOR gate proposed in the literature is studied. The numerical model for the circuit design was built by constructing differential equations fit for Matlab integration mechanism. Besides, numerical model for integrator saturation was built to make results of numerical simulation conform to that of circuit simulation. Analysis of the impact of integrator saturation was done. With the analysis and by changing the control voltage, NAND function was expanded for the original chaotic logic gate that was only able to function as a NOR gate. By adding the function control signal to the input end and setting the voltage of it to different levels, the computing unit becomes a real time reconfigurable one.

Abstract: Building mountains as the basic model for illumination model in the system of 3DGIS visualization. The establishing of this model adopts the approach of the global illumination model combine with the local reflection model and also the combination of shading and shadow. Complete the drawing of the shadow in the global illumination model ,using the shadow algorithm of Ray tracing as the main algorithm for drawing shadow, take advantage of shadow volume algorithm as the additional algorithm for shadow; complete the drawing of the shading in the local reflection model ,using the Blinn proportion algorithm as the main algorithm. Select the single ideal fixed point source as the light source of the illumination model. The results of this experimental show that the approach of combination of global and local model is feasible, the selection of the shadow and shading algorithms are also can reference.

Abstract: The high rate of coal mine accident gives our country enormous economic loss, gives human heart heavy striking, and gives our country bad impression in international society. According to accident-causing theory, human unsafe behaviors and unsafe conditions of thing are the main reason of accident. The paper analyzes the relationship of miners′ psychological characteristic and safety degree, quantifies miners′ safety degree and brings forward measures to improve miners′ safety degree.

Abstract: Due to some features of images, traditional encryption algorithms are not suitable for practical image encryption. Considering this problem, a novel feistel network image encryption algorithm is proposed in this paper. Taking advantage of the desirable properties of mixing and sensitivity to initial parameters of chaotic maps, a sub key generator with couple chaotic maps is presented in this scheme. Meanwhile, the encryption algorithm includes a new mixing algorithm which is designed with thirty s-boxes of AES. To enhance the security of the new scheme, the encryption processes were combined in feistel network. The results of analysis and simulation experiments indicate that the scheme is secure and performed well in preventing attacks, such as brute force attack, entropy attack and statistics attack.

Abstract: A secure electronic protocol, which can be used for electronic voting and electronic bidding, is proposed. The protocol is based on a new cryptographical model called secure multi-party proof that allows any players and a verifier to securely compute a function in the following sense: each of the players learns nothing about other players’ input and nor any information about the value of , and the verifier obtains the value of and its validity but learns nothing about the input of any of the players. In this paper, we firstly define and construct a secure multi-party proof for any polynomial time function with semi-honest participants and verifier, then construct our secure electronic protocol.

Abstract: According to the characteristics of multilateral horizontal well, by using pressure superposition and mirror image reflection theory, the mathematical model of steady percolation for multilateral horizontal well in bottom water drive gas reservoir is developed on the basis of a three-dimensional pseudo-pressure distribution model for horizontal gas wells. The wellbore model is formulated in consideration of friction loss and acceleration loss. After a case study with couple models, the effect of wellbore pressure drop on productivity of multilateral horizontal gas well is analyzed.

Abstract: The paper put forward a three-dimensional model of organizational learning in private enterprises, including organization system, private entrepreneurs and employees based on the analysis of the problems on organizational learning in private enterprises. Therefore, the research proposes several strategies, establishing learning organization, elevating professional qualities of private entrepreneurs and carrying out human-based management to enhance the capability for organizational learning in private enterprises in China.

Abstract: The simulation and analyses of a “bottoming cycle” solid oxide fuel cell–gas turbine (SOFC–GT) hybrid system at the standard atmospheric condition is presented in this paper. The fuel cell model used in this research work is based on a tubular Siemens–Westinghouse–type SOFC with 1.8MW capacity. Energy and exergy analyses of the whole system at fixed conditions are carried out. Then, comparisons of the exergy destruction and exergy efficiency of each component are also conducted to determine the potential capability of the hybrid system to generate power. Moreover, the effects of operating conditions including fuel flow rate and SOFC operating temperature on performances of the hybrid system are analyzed.