Applied Mechanics and Materials Vols. 34-35

Abstract: The lack of Chinese subjective lexicon in the study and application of the subjective and emotional information restricts the further development of subjectivity analysis of Chinese words. Based on the current situation of and demand for Chinese sentiment analysis, the method of automatically obtaining subjective lexicon from the target corpus is studied. A creation method of subjective lexicon is presented, the subjective lexicon and language model are defined, a self-adaptive subjectivity bootstrapping algorithm and the characteristic model of subjectivity attribute are designed, and all these lead to the realization of the automatic judgment of sentiment polarity, subjectivity intensity and the subjectivity and objectivity of a word in the subjectivity entry. Experiments prove that by using machine learning the proposed method of automatic creation of Chinese subjective lexicon is highly efficient and with excellent performance.

Abstract: The early warning can improve the monitoring and management of the hazard installations, realize the prevention and control in advance. Many early warning methods do not have the forecast and simulation of the hazard consequences and early warning information is not comprehensive. The hazard installations warning process and hazard assessment technology are analyzed and studied, and qualitative analysis and quantitative analysis are carried out. With the effective combination of hazard consequences and early warning technology, the processing system of hazard installation early warning process information is presented, the hazard installation early warning information processing model is designed, the hazard installation early warning is improved, and the accuracy and efficiency of early warning is improved. With examples, the hazard consequences of leak and diffusion are simulated. Experiments prove that the early warning simulation structure and early warning method are effective, and that the simulation results are close to the actual situation with better application value.

Abstract: In this paper, the main design parameters of seal structure for non-API pipe connection are studied. First, as the total contact pressure consists of the radial preload generated by interference fit and the radial pressure caused by gas pressure in pipe, the variation laws of their values changing with the sealing diameter are analyzed. The sealing diameter value which maximizes the total contact pressure can be obtained from the derivation formula for calculating the total contact pressure. Second, considering the yield condition of pipe connection under the internal and the external pressures, the minimum wall thickness of the seal structure is derived. Then the cone angle is calculated by the sealing length and the minimum wall thickness known. Finally, take the 7in casing connection for example, the main design parameters are calculated by the above analysis.

Abstract: Considering the various influencing factors of enrichment of coal bed methane, the evaluation indexes of enrichment for coal bed methane are determined. The weight values of all factors indexes are given and the fuzzy mathematics model is established on the basis of the fuzzy mathematics. As a case study, the fuzzy mathematics model is applied to the assessment of enrichment of coal bed methane. The results show that the No.5 coal seam of Shan 2 of Shanxi formation in Daning-Jixian is a better enrichment area. The evaluation result performed on the basis of the fuzzy mathematics model is in good agreement with the measured result. The example indicates that the method is credible and has high precise. The assessment system established in the paper can be regarded as a reference model in coal bed methane exploitation potential assessment.

Abstract: In order to know something about the structure reliability of beam pumping unit, the methods of Monte-Carlo and response surface method are used to analyze the pumping unit. According to the analysis and calculation, the approach of how to calculate and analyze the reliability of complex structure is obtained. The results show that using the method of reliability can make the pumping unit more reliable and reveal the components of pumping unit more clearly which can make the design of pumping unit more reasonable.

Abstract: In this paper the electric-hydraulic servo system for excavating robot is analysed. The kinematic and the dynamic model of working equipment are established. Aim at the electric-hydraulic servo system of the feature with many variables, strong coupling and non-linear, the CMAC neural network was presented combined with popular PD algorithm, which could realize intelligent control for the working equipment of excavating robot. The result of simulation show that control strategy features higher precision and robustness.

Abstract: Electroless Ni-P and Ni-P-Al2O3 composite coatings on low carbon steel (Q235) sheets were prepared by adopting optimum plating process. The cross-section morphology and structure as well as the phase transformation of the composite coatings were studied by scanning electron microscopy(SEM), X-ray diffraction(XRD). It was shown that the Al2O3 particles homogeneously dispersed in the entire Ni-P film matrix, and the structure of Ni-P-Al2O3 composite coatings as deposited was amorphous. The corrosion behaviors were evaluated by electrochemical tests. The experimental results indicated that the corrosion resistance of Ni-P-Al2O3 coatings was superior to Ni-P coatings due to the effect of Al2O3 particles. In addition, the oxidation resistance test, which was carried out by using oxidation weight method, showed that ternary Ni-P-Al2O3 composite coating had a better oxidation resistance than Ni-P coating.

Abstract: In this paper, based on the new concept air power of pneumatic system’s energy consumption, we proposed series of practical program to optimize the air supply system. This program discussed a method of how to keep air pressure stable and how to make the amount of air compressors to match the real-time air consumption after using different air pressure for different devices, thus reducing energy loss of air supply system and energy consumption of air compressor group. The result of present work implied that this program achieved the desired effect of energy saving and provided a reference for energy-saving pneumatic system’s design.

Abstract: The evaluation of stresses in engineering structures to provide early indications of stress status is a fast growing area in non-destructive testing. Metal magnetic memory technique is the magnetic stress measurement technique for ferromagnetic materials using passive magnetic fields to monitor changes in the magnetic properties of materials. This paper studied the physical formation process of metal magnetic memory effect. This paper studied the physical mechanism between stress and magnetic field in metal magnetic memory effect, through the influence of stress-induced magnetic anisotropy on magnetization process of ferromagnetic crystal.

Abstract: As the supporting means for the development of enterprise, the construction of management control information system requires to be improved and upgraded continually in accordance with the development of China mine enterprises. Facing to China mine enterprises, the management control information system of production and operation based on three-layer structure is an integrative solution by combining management and control. The three-layer structure includes Enterprise Resource Planning (ERP), Manufacturing Execution System (MES), and Process Control System (PCS). Composed by inter-related systems of PCS, MES and ERP, the comprehensive and automatic system architecture can integrate them as a whole through the promotion of control technology, computing technology, and optimization technology, and can achieve the comprehensive application of mine information, control effectively the operating costs in mine production, improve production and management efficiency, enhance the core competitiveness of enterprises, and enable the production and operation management of mine enterprises to make a substantial step up.