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Using elastic mechanics and fracture mechanics, analyzing the coal seam hydraulic fracturing breakdown pressure, given its theoretical formula. According to hydraulic fracturing stress status, given the form of two typical hydraulic fracture morphology. Analyzing hydraulic fracturing highly elliptical shape. The displacement field in plane stress state is given, and the theoretical formula of fracturing radius of hydraulic fracturing is deduced. The fracturing technology of underground fracturing is presented, and the fracturing location and fracturing parameters are determined. In Sihe Coal Mine conducted fracturing test, the test results showed that: the average of drainage volume of fracturing hole improved 4.4 times compared with non-pressed-hole. The extraction compliance time is reduced by 38%. Roadway tunneling speed was improved by 15%. It can solve the problem of gas overrun in roadway excavation well, and has a good application and popularization value.

Multi-depot heterogeneous vehicle routing problem with simultaneous pickup and delivery and time windows (MDHVRPSPDTW) is an extension of vehicle routing problem (VRP), MDHVRPSPDTW mathematical model was established. The improved genetic algorithm (IGA) is proposed for solving the model. Firstly, MDHVRPSPDTW is transferred into different groups by the seed customer selecting method and scanning algorithm (SA).Secondly, IGA based on elite selection and inversion operator is used to solve the model, and then cutting merge strategy based on greedy thought and three kinds of neighborhood search methods is applied to optimize the feasible solutions further. Finally, 3-opt local search is applied to adjust the solution. The proposed IGA has been test on a random new numerical example.The computational results show that IGA is superior to branch and bound algorithm (BBD) by Lingo 9.0 in terms of optimum speed and solution quality, and the model and the proposed approach is effective and feasible.

This paper introduces the design of permanent magnet that can been used to small nuclear magnetic resonance (NMR) system, and its static magnetic field simulation analysis uses Ansoft's Maxwell software. According to the theory of magnetic circuit design and the performance requirements of magnetic field, An H-style permanent magnetic actuator has been designed, and it can generate uniform magnetic field larger than 0.4 T in the interested region of this actuator. The static magnetic field simulation analysis of this permanent magnetic actuator has done by Ansoft's Maxwell 3D software, and the experimental results show that the design of permanent magnet can meet the requirements.

Currently, friction stir welding has had a wide application in connection of aircraft panels. However, researches are rarely carried on in domestic aeronautics field, which involves the differences between FSW panels and traditional riveted panels in aspects of strength and stabilities under various working conditions such as shear and tension and compression. Picture frame fixture was used in this research for comparison test between two types of aircraft panels, which were connected to stringers by riveting and friction stir welding (FSW). Finite element models were established to simulate the panels in the shear tests which proposed a method to simulate the connection types. It is found that the FSW connection performs better than riveted connection in aspects of limiting load and initial buckling load, which proved that panel connected by FSW is better than riveting in mechanical properties. The test result is proved by FEM simulation, and vise versa.

In order to improve the security and reliability of digital synchronization network, digital synchronized equipment mostly uses reference source design and ensure the output performance in abnormal situation by redundancy back-up of multiple reference sources. The paper not only describes the concept of time-frequency equipment reference source and its judgment index, but also details a multi-source dynamic determination algorithm for digital synchronization equipment. A multi-component weighted average approach is designed the multi-source dynamic source selected processes by the study of several time sources of anomaly detection to improve the accuracy of the synchronization signal. The algorithm with simple structure can help keeping the high synchronization accuracy of multi-source time synchronization system.

For traditional intrusion detection technology, the lack of intelligent and self-adaptive has become increasingly prominent when they cope with unknown attacks. A method based on genetic algorithm was presented for discovering and learning the intrusion detection rules. This algorithm uses the network data packet as an original data source, after pretreatment, initialized them to be the initial population of the genetic algorithm, then derive the classification rules. These rules were used to detect or classify network intrusions in a real-time network environment, selecting the intrusion packets. The experiment proves the efficiency of the presented method.

Halbach magnet array has advantages of its small size and yokeless, so it has been widely used in various areas. In this paper, two Halbach permanent magnet arrays for small-size NMR with cube and octagonal shape, respectively, were compared in parameters of average magnetic field strength, field homogeneity and volume with the same material consumption. It was found that the octagonal shape magnet has better performance than the cube one. Then the field homogeneity optimization for octagonal magnet was performed. By analysis of magnetic field strength, the best homogeneity in 5mm DSV (Diameter of Spherical Volume) with 133.4ppm was achieved when the height of magnetic blocks is 16.25mm. After optimization, the magnetic field homogeneity has been significantly improved when the shape of magnet has small volume. This result laid a foundation for the design and manufacture of the octagonal Halbach permanent magnet array in small size.

The paper develops an evaluation model using Data Envelopment Analysis to measure structure efficiency of energy terminal consumption - based on input-orientated measures in input structure (IIS Model). Specifically, the input structure efficiency (ISE) defined as the ratio of technical efficiency scores of ISS model over IMS model will be used to evaluate efficiency in terms of the structure of energy terminal consumption. The empirical data are used in the proposed analysis on the structure efficiency of energy terminal consumption in regions of China from 2000 to 2011. The results show that the overall level of the structure efficiency is lower and the structure of energy terminal consumption does not reach the optimization. There is a huge room for future improvement in terms of energy efficiency by optimizing the structure of energy terminal consumption. In addition, the results of correlations in regions show that there are several important managerial decisions which need being further explored.

The main building of the Hubei press has a horizontal contacting passageway in the middle of two buildings in the fifteenth floor, which has attractive appearance and like a doctorial hat from afar. The structure is reasonable and more stable with the diagonal bracing and the beam. Analysis and research in this paper can provide reference for the design of this structure.

The Tessiers five-stage sequential extraction procedure for extractable heavy metals determination was applied to sludge samples collected from wastewater treatment plant of Yanan city, Shaanxi province, China. According to the Tessiers guidelines, Copper (Cu), Zinc (Zn), Nickel (Ni), Cadmium (Cd) and Chromium (Cr) were determined by atomic absorption spectrometry (AAS). The heavy metal concentrations from high to low are Cu > Zn > Ni > Cr > Cd, which are lower than maximum permitted levels for agricultural use in relation to current international legislation. As shown in the speciation experiment, Cu mainly exists in organic form and sulfides, which is relatively stable. Zn with potentially hazards mainly exists in iron/manganese form. Ni mainly exists in insoluble form, which is stable and not easy to migrate to the environment. Cd with potential biological effectiveness mainly exists in acid soluble form and is easy to migrate to the environment.

Aimed at multi-pulleys timing belt transmission system of automobile engine , programing parametric design software based on visual C++, set up timing belt and pulleys 3D model , Improve the design efficiency by design chart and data programmed processing .through comparison of conventional design result , verify the software feasibility and exactness.

The ultrasonic technique is a new method for detecting the borehole sediment thickness and has been gradually developed in recent years. However, there are still several key technologies needing to be further studied and developed. This paper focuses on studying and designing the ultrasonic processing circuits including the mono-stable flip-flop circuit, the driving circuit, the amplification filtering circuit and the automatic gain control circuit. Under the environment of Multisim10.0, the designed circuits are simulated. The results show that the deigned ultrasonic driving circuit has a strong driving capacity and is capable of completely meeting the bandwidth requirements in measuring the sediment thickness by ultrasonic. The automatic gain control circuit is capable of strengthening the ultrasonic signal in a time varying mode so that the output signal can be kept stable within the given range. So it has a significant effect on the ultrasonic measurement of sediment; the designed amplification, filter bandwidth and the quality value can all meet the system requirements. Meanwhile, the integrated filter is adopted and few peripheral components are used, therefore, the system design is greatly simplified.

The paper is based on surface gas extraction technology from boreholes in the goaf in Zhangbei Coal Mine ,Huainan Mining Group .With the method of numerical simulation ,the authors have made analysis on the space-time cracking and moving law about the overburden of mining field during exploiting by contrasting extraction data about boreholes in Huainan Mining Group .Besides ,paper provides conclusion and advices on promoting the stability of borehole in the end .To some extent ,the paper is of instructive significance for the research ,promotion and application of gas extraction technology from the goaf .

Dynamic behavior of a vehicle-bridge system model is presented. A set of time-varying equations of the system considering roughness surface of bridge are given. The equations are rewritten in the form of matrix for numerical simulation. Modal analysis of the equations is carried out. Simulation and visualization of the equations are given. Effects of different speeds and accelerations of moving vehicle and roughness surface of bridge on the vertical displacement of mid-span of bridge are studied.

Several earthquakes record that the residential fills always suffer severe damages. In order to know the seismic damage mechanism and evaluate the damage extent of residential fill ground, research is carried out on two fill grounds in the eastern part of Kyoto basin. The research includes field survey about terrain condition, geological condition, development history, disaster condition during 1995 Kobe earthquake and surface wave explorations. Some remarkable conclusions are summarized as follows: In Jyodo-ji area, it is a residential fill on soft alluvium ground. The geological condition is back swamp. The thickness of surface fill soil is about 1~4 meters. In Kiyomizu-dera area, it is a valley filled ground. The geological condition is hilly platform.

Being compared with traditional wear resistant materials, the corrosion resistance of high boron iron-based alloy at 25°Cand at 60°Care researched respectively. The results show that the corrosion resistance of wear-resistant alloys decline at high temperature. At 25°C and at 60°C, though the corrosion resistance of high chromium cast iron is a little higher than that of high boron iron-based alloy in acid medium (PH=3), high boron iron-based alloy’s corrosion resistance is the best among these three materials in neutral medium (PH=7) and in alkaline medium (PH=12).

A vehicle-bridge system is simplified as a model of Euler-Bernoulli beam subjected to kinds of load. Dynamic behavior of the beam is researched in this paper. Several equations of the beam traversed by static or moving load and mass are given. Some of these equations are time-varying nonlinear. In order to avoid the problem of instability solving the equations, precise time integration method is used. Results show that the transversal deflection of the mid-span of the beam is greater when a harmonic force or a mass is traveling on the bridge at a lower velocity or by accelerating.

Distributed fiber Bragg grating (FBG) sensing technology is used to measure the bending stiffness of a thin-walled aluminum tubes beam. In this work, the FBG sensing method is introduced, and the test result is compared with the nominal value based on the traditional mechanics of material computation.

In this paper, the STIRPAT model has been used for quantitative research of the driving factors of building energy consumption in China. We use the ridge regression method to obtain the regression equation between building energy consumption and five key driving factors, including population, urbanization rate, household consumption level, per capita living space, and the development of the tertiary industry. The results show that the comsumption level has higher influence on building energy consumption in China than the other four factor, and the influence of the tertiary industry and building area factors is inferior. The influence of population factor on the growth of building energy consumption is small, but the distribution of urban and rural population factors (urbanization rate) have greater influence than the total population factor.

This paper presents a new vibration isolation module which is set somewhere out of pier footings of footbridges. The isolation vibration effect of the vibration isolation module was analysed by means of experiment and FEM analysis. The attenuation decibels of the vibration strength were measured and researched under various working conditions. Making use of the finite element program, the new vibration isolation module was simulated and calculated. That the calculated results were in good agreement with the measured ones indicated the reliability of the numerical model. The simulation and measured results suggest that vibration reduction effects are satisfactory. The results can provide reference for vibration attenuation and vibration isolation of footbridges.

The simulation analysis of the cantilever construction process was carried out with the structure analysis software. This paper provides an overview of the geometric control and the overall computation according to actual criterion, taking into account the effect of temperature, concrete shrinkage and creep, pre-stressed tension and so on. The elevation monitoring was carried out by comparing the calculated values with testing data. The analysis and control of the line shape are good to perfect the construction control technology of the closure section, enhance the closure quality and ensure the smooth of entire line shape and the rationality of the main beam internal force.

An indoor simulation experiment has been carried out to study the effects of Roxarsone on the soil neutral phosphatase, catalase and urease activity. The result showed that the enzyme activities were reduced by the Roxarsone, and the effect degree was aggravated with the increasing consistency. It also showed that inhibition of various enzymes on the rise - decrease trend during the whole incubation period reached its peak on the tenth day as 54.71%,33.92% and 13.81% sorting the phosphatase, the catalase and the urease in a descending order consulting the enzyme sensitivity to Roxarsone. Taking the ED10 as an example, which is 18.83, 48.31 and 185.2 mg.kg-1 on the tenth day: Negative exponential growth model were used to fit the regression rate of enzyme activities with time indicating that the time of Roxarsone toxic effects on soil enzyme extended with the consistency being increased.

Focusing on the application technique of the phase testing techniques in cell identification, the analysis to the morphological structures of the leucocytes is done, and the physical models with nucleus of white blood cells are built. Based on the VirtualLab and numerical simulation techniques to systematic study on the distribution of the phase of the the leucocytes, the inside and outside morphological structures of the leucocytes and the main characteristics of the models are found. Thus, the phase testing application has been expanded. The light phase distribution analysis of biological cell is expected to become a new tool to detect the biological cell.