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Gas disaster and prevention is the critical issue in heading laneways of underground coal mine. There are two goals needs to meet, one is air quantity requirement and energy conservation during normal ventilation, the other is safety and quickly during gas outburst. Firstly, gas migration character and auxiliary ventilation system placements are described in detail. Since two control goals need to reach, a dual-mode fuzzy control strategy for auxiliary ventilation is established. Besides weight calculation method which harmonizes subjective and objective weight calculation is put forward. After then, a gas discharging experiment platform including PLC controller, converter and heading laneway simulation model is established on the basis of theoretical analysis and simulation results. Finally, experimental results have shown that the system can safely and efficiently fulfill the function both at normal ventilation and gas discharging.

In this research, an experimental apparatus that composed of adiabatic packed absorption and regeneration columns was established to simulate H2S removal process. The results show that the reaction between CO2 and MDEA can be regarded as a rapid pseudo-first-order reversible reaction and the CO2 absorption mainly is controlled by liquid film resistance while the reaction between H2S and MDEA are reversible instantaneous. For H2S absorption, it is mainly controlled by gas film resistance but the rate of liquid film resistance to the total resistance of H2S absorption was distributed from 25.7% (column bottom) to 12.6% (column up).

Informatization is an inevitable trend in the world development. Accounting informatization is an important part of enterprise informatization. Focusing on the connotation of accounting informatization, this paper firstly analyzes the current situation of the accounting information in China. Then it points out the existing problems of accounting informatization in China. These problems include lack of understanding of the nature and importance of accounting informatization, lower overall quality of accounting personnel and the lack of integrated talents, realizing information resources sharing with difficulty, blind investment in accounting informatization construction and poor universality and standardization of financial software, and threatened data security. Finally it puts forward the corresponding countermeasures to promote the healthy development of accounting informatization in China.

Recently, 3D printing technology has obtained the rapid development which brings immeasurable changes. It is considered to be one of the main marks of the third industrial revolution. The shares of Avic Heavy Machinery co., Ltd (600765) involving 3D printing technology continuously hardened six times in January 2013.Taking it as an example, we expound the connotation and advantages of 3D printing technology seriously and also elaborate the background of 3D printing technology. In addition, by analyzing its operation ability, profitability and growth capacity, we find the shares of Avic Heavy Machinery co., Ltd (600765) hardened on account of 3D concept hype, and not its performance. Then we describe the existing problems in the development of 3D printing technology in our country. Finally we give some corresponding suggestions to the development of 3D printing technology from three angles.

The limestone-lime washing technology is the most widely used WFGD process, which normally we adopt to control the discharge of SO2 caused by coal’s combustion. Through the research on the oxidation kinetics of sulfite in this paper, it is indicated that macroscopic chemical reaction which responses to rate of sulfite is 1/2. And the results of orthogonal test can be concluded that: to the extent influence of oxidization reaction rate, the influences of temperature is the most significant, and influences of stirred speed is nearly negligible. The optimized operation factors may be shown as that temperature is controlled at 40°C, air ventilation is at 88ml/min,pH is 4.5 and stir speed is 500 r/min.

Mini wind generator is an efficient way to save electricity and develop the potential green wind energy in city environment. The material and structure design of the supporting frame is a key factor to ensure the generator work fluently and safely for manufacturing engineering. In this research, the dynamic properties of the frame with different structure materials are analyzed by finite element method. The epoxy frame has the fewest number natural frequencies coinciding with the generator working revolution frequency. And the mode shapes of epoxy frame of different orders are achieved by FEM. A new kind of analytical method, key node component-displacement criterion is proposed with respect to the displacement characteristic of the frame under different mode orders. This criterion provides a new approach in evaluating the deformation characteristic of the dynamic properties of mechanical structures.

Based on the investigation and analysis of the causes of Dongchuan landslide, as well as on the stability analysis of Dongchuan landslide No. 1 and No. 2,it was presented by use of surface drainage, anchor pile, prestressed anchor cable lattice beam and other engineering measures on Dongchuan landslide to conduct comprehensive management. The deformations of treatment landslide were monitored and analyzed. The monitoring results show: the greatest deformation of the landslide is 8mm and the slope is a basically stable. Therefore, combined anchor piles, prestressed anchor cable lattice beam with drainage can well manage landslid

Accurately surveying out the fault, facture zone, water status and other bad geological phenomenon is the key problems for safety and quality in tunnel construction. Based on the different dielectric electrical differences in characteristics, applying geological radar detected the adverse geological in front of the tunnel face and analyzed. The results show the rock in front of tunnel face is broken, the bedding joint is developed, and there is jointed intensive moisture content with the local rich water. In construction process, the support should be strengthened, excavation method should be adjusted)

A new kind of mini wind generator system has been presented for saving city electricity and developing potential green wind energy between high buildings in city environment. The support frame of this generator system is a key structure part. Stress conditions of this frame under different kinds of structure materials are analyzed with finite element method. The concentration of stress along frame pillar is achieved by the FEM results. A new analytical method, specified stress criterion is proposed with respect to the design of generator system. This criterion provides a new approach in optimizing the kind of material in structure design taking into account the material plastic properties. With regard to specified stress, glass fiber-reinforced epoxy is the best candidate material for supporting frame.

The Niutuozhen geothermal system, located in North China, is composed of the Jixian system dolomite reservoir and a Neogene sandstone reservoir. A three-dimensional model with 5437 elements and seven layers based on the geological and geothermal data was built using the AQUA3D package designed for solving flow and heat transport problems. Production history of forty five wells and pressure monitoring data from six wells were used for calibration. The calibrated model was then used to predict the geothermal system response of the geothermal field. The maximum predicted drawdown after 20 years of production without any reinjection ranged from 30 to 120 m in the north and south, respectively. The rate of drawdown was predicted to be kept at a lower level if 50% of the produced water was reinjected into the system. Cones of depression were predicted to gradually enlarge due to an increased production rate without reinjection, but were effectively limited and even diminished with a reinjection ratio of 50%. A maximum temperature decrease of 2.75°C was predicted to occur in production well A34, located near the reinjection well R3, for a production rate of 162 l/s with 50% reinjection. The maximum temperature decrease of 24.81°C was predicted to occur in the southern reinjection well R2. Prediction of temperature response indicated that the reinjection rate, the temperature of the reinjected water and the distance between the reinjection and production wells are the three factors affecting the reservoir temperature change. Reinjection is a indispensible measure for maintaining pressure of the reservoir. However, reservoir cooling induced by reinjection of the cold water should be considered carefully.

Embankment filling is a process step by step. The influences of its filling height changes on the stress and deformation can not be reflected in a load. However, in the actual construction, it leads to quality accident in embankment construction that filling usually doesn’t control the thickness according to the requirement of construction specification. In order to reveal the stress and strain law of about 72 m high rock-filled embankment during the construction, and provide a scientific reference to construction quality control of the embankment, according to the typical cross section of the Hurongxi highway, using two loading modes to simulate the embankment filling, the internal stress, strain and corresponding graphics of different control points of the embankment under the various loads were presented. The results of the two loading modes are analyzed and compared. It shows that the settlement, stress and construction quality control points of the embankment are different and larger under the different loading

This paper describes a basic method of mechanical design and virtual teaching of a two-leg walking mechanism, mainly including the assignment of the degree of freedom (DOF), the process of kinematics and Kinetics computing, the selection method of driving devices and the principle of the virtual teaching system. The fact proves that this two-leg walking mechanism is of high stability and efficient teaching.

In this study, a high performance liquid chromatography coupled with electrospray ionization mass spectrometry (HPLC-ESI-MS) method for the determination of eight endogenous peptides, which included angiotensin-II, neurotensin, 5-met-enkephalin, 5-leu-enkephalin, somatostatin, bradykinin, dynorphin A and oxidized glutathione, was developed. MS parameters were optimized in order to obtain the best signal intensity. The optimum MS parameters were: fragmentor: 100 V; nebulizer gas (N2) pressure: 40 psi; drying gas (N2) flow rate: 10 L/min; drying gas temperature: 350 °C; capillary voltage: 2000 V. Validation of the method showed positive results. The correlation coefficients (R2) between the peak areas and the corresponding concentrations of peptides were greater than 0.9903. The limits of detection (LODs) (S/N = 3) of the eight peptides were 3.88 ng/mL ~ 17.5 ng/mL. The developed method had been successfully applied to analyzing the human plasma fortified with the eight peptides, which indicated the potential of the methodology for the analysis of biological sample.

On the basis of LuGer friction model, an integrated sliding-mode control strategy is proposed to deal with servo system nonlinear and uncertain factors effectively. The control strategy includes two parts. One is nominal model without considering disturb and uncertain, the other is real model including disturb and uncertain. To one part, choose reasonable sliding surface and design controller law. To another part, PTSC algorithm and NNC algorithm combines together to optimize RBF neural network in order to acquire upper bound of uncertain. Simulation and experiment results show that proposed control strategy better servo system performance.

It is difficult to fulfill effective control since nonlinear and uncertain factors for an antenna servo system. In this paper, a compound sliding-mode control strategy is proposed. In order to control servo system effectively, depart it into two parts. One is reference model without considering disturb and uncertain, the other is real model including disturb and uncertain. To one part, choose reasonable sliding surface and design controller law. To another part, RBF neural network is taken in order to acquire upper bound of uncertain. Simulation and experiment results show the effect of control scheme.

The research of this paper focused on bond characteristics of overlay-substrate interface in ultra-thin white topping(UTW), aim at ultra-thin concrete overlay on old concrete. Compressive and shear stress have been considered in the structural analysis and experimental research. Bonding behaviors of several surface pretreatments to old concrete have been investigated. A shear-peel test device has been developed to imitate brake-load of wheels at the plate boundary of UTW, and its analytical calculate principle have been discussed to simulate the mechanical theory of the shear peel test. Structural analysis and experimental research results indicate that various flaws are accumulated remarkably in the transition layer at overlay-substrate interface in UTW. Different surface pretreatments of the old concrete will influence on the bonding characteristics of overlay-substrate interface, chiseling treatment for interface has more contribution to working together with the new concrete, but interface adhesive agent enhances the coordination between the interface and the old concrete layer. The treatment combination of chiseling and brushing interface adhesive can effectively improve the strength of the weak interface transition layer. Shear-peel test results indicate that the interlocking influence generated by chiseling treatment is prior to brushing interface adhesive. It is necessary turn to account suitable measure to prevent ultra-thin concrete overlay peeling off from old concrete.

Based on the summary of the status of land subsidence research, Biot Consolidation Theory is proposed to analyze the coupling of seepage field caused by precipitation. By use of Biot consolidation two-dimensional plane finite element calculation programmed, the land subsidence of the WenZhou Yongqiang plain caused by the exploitation of underground water was analyzed. The results are more in line with the measured data, so the method for analysis of possible land subsidence is practicable.