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Wind power prediction is a key problem in optimizing power dispatching. This paper builds a wind power prediction model based on wavelet neural network which substitutes wavelet basis function for the transfer function of hidden layer. A missing data interpolation strategy is also given to improve the applicability of the model. With the wind farm data from southeast coast, the model works and the wind power in the next 30 hours is predicted. In the sense of the mean square errors this paper compared the prediction results of the model and BP neural network model, the results shows the models have a better accuracy.

For the current avionics system structure of typical military aircraft, this paper proposes the architecture design of airborne embedded training system ,and detailedly discusses the functional structure scheme of the training system, composition of hardware and software etc. This paper deeply discusses credibility and effectiveness inspection scheme in the system development process, and takes embedded training system and the integration process of the fire control radar for example, this paper also does simulation and analysis of simulation.

It has been proved that the mold filling under low pressure casting can be described by the second order nonlinear differential equations characterized by damping oscillations. To obtain higher accuracy of the velocity field, the mold filling process with damping oscillations should be considered. A computational model taking the liquid level droping in the crucible into account based on two phase flow for filling process of damping oscillations is presented in this paper. Hydraulic simulation with the particle image velocimetry was adopted to verify the numerical simulation result. It is proved that the nemuerical simulation results used the presented model perfecly match with the particle image velocimetry results. Liquid level droping in crucible is the main reason for damping oscillations in mold filling. Velocity oscilations can be eliminated when the melt flow across a sudden expansion section. The detailed flow field based on the presented model can provide guidance to optimize the process parameters.

The refractive index of double-distilled water and inorganic salt solutions of concentrations varying from 0.4 to 100 ppt (‰) have been measured at 20 Celsius degrees using Abbe refractometer, respectively. The inorganic salts such as NaCl, MgSO4, KCl and MgCl2,these forming the major constituents of seawater are used as solutes of the water solution. The effect of the concentration of these constituents on the refractive index of the solution is experimentally investigated. And meanwhile, the index of refraction studies are carried out for the laser wavelength of 405nm, 450nm, 532nm and 633nm under the case of varying concentration. The results show that the refractive index of the solution will be linearly increased with the increase of the concentration of these constituents. The index of refraction differs for the different solutes when their concentration is same at a certain wavelength.

The Polarized light microscope and DSC are used to study the influence of the nucleation agents’ type (The aqueous dispersion of isotactic polypropylene wax and the commercial nucleating agent TMB-5), nucleating agents’ content on the β-crystal content, melting points of α-crystal and β-crystal are studied in the paper. The difference of their capacities of inducing the crystallization of polypropylene are compared and analyzed. The foundation of the treatment of the aqueous dispersions of isotactic polypropylene wax on the reinforcements to induce crystallization on the surfaces of the reinforcements is laid.

The aqueous dispersion of MAH-g-PP and KH-550 solution are used in the pretreatment of GF. The effects of pretreatment of the aqueous dispersion of MAH-g-PP and KH-550 solution on the interface crystallization of PP/GF, the suitable temperature and time of the pretreatment of the aqueous dispersion of MAH-g-PP on GF are studied by scanning electron microscope (SEM) and polarized light microscope (PLM). Finally, PLM is used to study the effects of the aqueous dispersion of MAH-g-PP on the crystallization of PP.

Based on the introduction of the hydraulic diagnostic techniques which are commonly used and existed defects in these methods, the active hydraulic diagnosis technology is put forward. Besides, theory analysis of active online test is elaborated. The theory of active diagnose is used in the hydraulic system of heavy transporter to describe online diagnosis method. The results show that the active hydraulic diagnosis is appropriate for all kinds of hydraulic system which is a general diagnosis method.

In water polo competition of robotic fish, due to the influence of factors like ripple disturbance, target point drift and image acquisition delay, the angle between robotic fish and water polo that competition platform return has great error. To improve the shortage, this article put forward an optimal angle estimation algorithm based on Kalman filter. Let the angle go through Kalman filter to eliminate error interference in process and measurement. So that output angle approach truth value. Results of experiment prove that this method can effectively get the better angle between robotic fish and water polo.

To study the grouting detection standard of Karst roadbed based on resistivity method, transient Surface wave method and electromagnetic wave CT, the typical test areas in the Karst roadbed of NANNING-GUANGZHOU railway are selected, and the field test research of grouting detection standard of Karst roadbed was studied by the above three geophysical methods. The grouting qualified Karst roadbed was determined by multiple methods of borehole coring and field water pressure after grouting, and the test results of Karst roadbed grouting qualified was confirmed effective sample. The difference value of resistivity, surface wave velocity and electromagnetic wave absorption coefficient of limestone layer, clay, pebble soil and Karst cave was statistical analyzed based on the effective test data, and preliminarily obtained the detection standard of Karst roadbed grouting effect based on the above three geophysical methods.

The dynamic experiments about the conversion of CO2from simulated flue gas were carried out in a bubbling reactor containing a kind of adsorption with M dissolving in ethanol and water at atmospheric pressure. Based on the results of product analysis and electrode potentials, the reaction mechanism of CO2reduced by M was deduced. The results of dynamic experiments showed that the reaction order was 1.0, the rate constant was 5.91×10-2s-1, and the apparent activation energy was 23.47 kJ·mol-1.

Wire race ball bearing with large radial size and small axial size, saves space extremely, and is widely used in rotary devices of large machineries. This paper establishes a mathematical model of optimization design of rectangular cross-sectional wire race ball bearing,and considers minimum friction torque as objective function, and analyses constraints of contact intensity and design specifications of wire race ball bearing, and forges an optical design method that determines the number of balls, the diameter of ball, the contact angle and the diameter of ball center circle as optimal design parameters, to attain the purpose of extending bearings life. Comparing results of Optimization with original sample, the friction torque of ball that bears maximum load reduces by 10.20%. This method provides a reference for conducting further scientific researches on wear of wire race ball bearing.

Considering the weight and loading conditions of the multi-shaft transmission box, build the finite element model and mathematical model for the box using the finite element method. According to ANSYS WORKBENCH, calculate the boxs load capacity and stress and deformation distribution under 9 working conditions then evaluate its strength and rigidity. Optimize the structure of the box to reduce its weight. The results show that the optimized box meets the strength requirements. After optimization, the multi-shaft transmission box weights 176.578 kilograms, reduced by 30.26 percentages. It improves the stress and deformation distribution and makes the structure more reasonable. It also provides important theoretical significance and engineering practical value.

With the rapid development of computer networks,more and more measurements need to relay on the network.But there are only a small amount of instruments with network interface.To access the network,we design a network agent for the instruments with different interfaces. We connect the host with the instrument through the network agent.The agent communicates with the host by using HiSLIP(High-Speed LAN Instrument Protocol ).The client soft front panel controls the instrument based on the VISA(Virtual Instrument Software Architecture) and HiSLIP.We use the Labwindow/CVI to design the soft panel.We can use the soft front panel to manipulate the instrument by the agent quickly and easily.

To promote the demonstration and guidance effect of scenic highway with the project post evaluation, this paper studied the concept of harmony scenic highway and built a Scenic Highway harmony evaluation system which takes highway road area harmony, human road harmony and highway external environmental harmony as core indexes. Scenic highway harmony evaluation method based on interval approximation was adopted to post evaluate typical demonstration scenic highway in Hebei. The practicability of the scenic highway harmony evaluation method based on interval approximation was verified.

Secondary effluent of sewage treatment plant directly reused in power plant circulating cooling water system was the main cause of scale inhibition in the system.Facing this serious scaling problem,static scale inhibition experiment was carried out to filter out the efficient compound formulation.Corrosion inhibition performance by rotary coupon experiment was studied.Scale and corrosion inhibition effect under the field condition by homemade dynamic simulation experiment and the environment toxicity were tested. The result showed that this water treatment agent gain the high scale and corrosion inhibition effect, with low phosphorus,non-toxic,friendly to environment.

As an effective and economic technique for flow range enhancement, casing treatment is widely employed to increase stability margin of compressors. In order to explore the effectiveness of casing treatment on performance of centrifugal compressor under multi-working conditions, in the present thesis, numerical analysis of three kinds of inlet recirculation casing treatment and a smooth untreated casing compressor models were carried out. The numerical results coincide well with the experimental data of optimal model and accurately predict the position of surge line, which verifies the reliability of numerical method which applied in this thesis. The results also indicate that, only reasonable configuration of the inlet recirculation casing treatment could significantly enlargement the stable operating range of the compressor at low flow rate under all rotation speeds. In addition, the slot position and front deflector baffle of the casing treatment have a great impact on its performance.

Smart Grid framework to achieve clean energy friendly access, to achieve energy conservation and reduction of environmental pollution, is to build the smart grid hallmark. Photovoltaic power plants grid, although to bring some impact on the grid, but also a certain role in promoting on the line loss rate decreased. This ignores the impact of other factors, only from the perspective satisfy voltage constraints, analyzing PV power plant different grid location and grid capacity for line loss rate.

Marine development activities have a great impact on the Marine environment. Laser transmission has been widely used in marine communications and imaging technology. Due to the different proportion of the chemical composition of seawater in each Ocean field, the laser transmission characteristic in seawater is also different. The transmittance has been measured and calculated in a constant transmission distance in this experiment, by four different wavelength lasers and different concentrations of the various chemical components of the seawater. Then the data were analyzed by transmission curve fitting. The conclusion of this experiment is: for relatively pure seawater, the transmission characteristics of blue - green laser is better than the purple or red laser, and green laser transmission characteristics is better than blue laser; for larger impurities seawater such as Tianjin seawater, the transmission characteristics of red laser is better than the other three wavelength laser.

PON technology is widely accepted as primary solution in the broadband access networks. Protection is an important issue in PON system while only protection of tree topologies has been studied and other topologies are ignored. This paper presents a comprehensive study on the protection schemes of two-stage cascaded PON with different topologies including tree-tree, tree-bus, ring-tree and ring-bus topologies. The reliability and protection issues were studied using reliability theory and numerical simulations. Results show that ring-bus topology has the best performance.

Wireless sensor networks with highly dynamic characteristics and limited resources, this paper presents a simple service level management protocol. It realizes service deployment management across different clusters, the request and the response of wireless sensor is simple that based on the protocol data format of XML WSNXML between the clusters. It provides an effective method for the management of shared resources of wireless sensor network and service expansion and realizes service release and deployment management difficulties between various wireless sensor network management based on different management cluster.

Land Use/Cover Change (LUCC) is a commonly concerned issue. The CLUE-S model was applied to Yangzhou urban area in this paper to simulate the land use spatial distribution in the urban area from 2003 to 2010. Combined with RS & GIS technology, three periods of remote sensing images were firstly preprocessed and three periods of land-use maps were obtained by means of object-oriented method. Then, corresponding model parameters were defined in the CLUE-S model to obtain the spatial distribution of land use of Yangzhou urban in 2003~2010. After that, the extracted and the simulated land use maps in 2007 were compared to evaluate the simulation accuracy. CLUE-S model can be used to simulate the distribution pattern of the development of smaller-scale regional urban space, to provide guidance for the smaller scale urban development planning, and is worthy of popularization and application of land use and land cover change model.

Noise is one of the common faults in hydraulic system. The correct analysis and deal with the noise will make for the normal operation and optimization of the system. In view of the noise of a new self-propelled transporter suspension hydraulic system produced in the debugging process of the heavy load lifting when suspension falling, by means of mechanism analysis, modeling and simulation analysis of the suspension hydraulic system, finding out the noise comes from the hydraulic component of system with SV type pilot check valve; The noise fault is caused by the improper circuit design of hydraulic system, the feasibility of the using the SL type pilot check valve to eliminate suspension hydraulic system noise proved by the simulation analysis, in the field test of the improved suspension hydraulic system, the suspension falling gentle and noise elimination, which shows that the analysis and simulation model is correct; Through the comparison and analysis on the SV type and SL type kinds of pilot check valve on the reasonable application in the hydraulic circuit isolation, that provides a theoretical basis for the correct selection two kinds of pilot check valve.

In this paper, we have proposed a new algorithm for pitch detection and an idea for harmonic separation based on pitch detection. Firstly, we have introduced the pitch algorithm. It is mainly consisted of five parts: mean value removal, extraction of alternative pitch periods, best pitch transfer path search, accurate pitch period search with time-varying filter and the search of fractional pitch period. Then we have brought in a harmonic separation algorithm based on the pitch detection. The pitch detection algorithm and harmonic separation algorithm proposed in this paper is mutually beneficialExperiments results show that the new pitch detection algorithm can achieve higher accuracy. And compared with some other algorithms, this approach owns a better noise immunity. The harmonic separation algorithm can separate each harmonic signal accurately.

After research on RIPv1 and RIPv2 of Dynamic Routing Protocol, simulation and modeling for RIPv1 and RIPv2 based on Packet Tracer simulation software. In the same simulation network topology, the simulation experiments compare RIPv1 and RIPv2 with the routing table, route update messages, route summarization, and the function of discontinuous network. The simulation results show that RIPv2 has more advantage than RIPv1.

In this paper, Computational Fluid Dynamics (CFD) is used to analyze the micro self-vibration of aerostatic bearing with pocketed orifice type restrictor as the bearings performance is stable and it is widely used ultra-precision equipments. By using Large Eddy Simulation (LES), time-variation flow field inside the bearing is obtained. Then the pressure fluctuation characteristics is discussed because it influences the micro self-vibration of the bearing directly. Moreover, the relationship between bearing diameter, orifice diameter, air chamber diameter, air chamber depth and the micro self-vibration is researched. The results can be considered for the designing of ultra-precision aerostatic bearing with pocketed orifice type restrictor.

In classification, when the distribution of the training data between classes is uneven, the learning algorithm is generally dominated by the feature of the majority classes. Features in the minority classes are normally difficult to be fully recognized. Hyper-sphere support vector machine is an important method for unbalanced classification which is an important issue, but this algorithm has a defect. In order to significantly improve the classification performance of imbalanced datasets, we propose a new method based on Generalized Hyper-sphere Support Vector Machine to enhance the classification accuracy for the minority classes. Support vector machine (SVM) is then used as the base classifier to train the reprocessed dataset. Our experimental results demonstrate that the proposed selection technique improves the classification rate of the rare events, and it also improves the overall accuracy of SVM without data pre-processing.

The Particle Swarm Optimization Algorithm is a new computational method for the combinatorial optimization problem, it is simple and effective, but it does suffer from the premature convergence. For overcome this problem and finding the optimal solution of the Stochastic Loader problem, we presented a new hybrid Particle Swarm Optimization Algorithm that combines with Artificial Immune Algorithm, such as immune memory, antibody promotion and suppression, immune selection and so on. Numerical example illustrates the higher efficiency and reliability of the new hybrid PSO compared with the basic Particle Swarm Optimization Algorithm.

A novel wet process has been developed to simultaneously remove NO, SO2 and Hg0 from flue gas. According to the conditions of the bubbling reactor, diperiodatocuprate (Ⅲ) coordination ion solution was prepared with CuSO4•5H2O, KIO4, K2S2O8, and KOH, and the effects of the various influencing factors, such as diperiodatocuprate (Ⅲ) coordination ion solution concentration, reaction temperature, solution pH on removal efficiencies were investigated. The removal efficiencies of 98% for SO2, 90% for Hg0 and 56.8% for NO were obtained, respectively, under the optimal experimental conditions, in which diperiodatocuprate (Ⅲ) coordination ion solution concentration was 6 mmol /L, the reaction temperature was 323 K, and the solution pH was 9.0. That [Cu(OH)2(H3IO6)]- was the main existing form of the absorbent at the optimal experimental conditions was confirmed by calculating the concentration ratios of IO4- and its dissociation products / [IO4-]ex under different pH, and thereby simultaneous removal mechanism for SO2, NO and Hg0 was proposed.

The grid is one of the most important ways of distributed power generation.Micro-grid existence provides a new approach to solve the contradiction between the large power grids and distributed power.This paper studies the stability of Micro-grid contained DG. It establishes the simulation model of typical Micro-grid and studied the impact of transient stability in micro-grid by different fault types and different fault points. Look for the general rules of Micro-grid stability impact by different control mode and different disturbance. Dynamic response curve of Voltage and frequency in micro-grid is reached .Analysis of simulation results, this paper gets the general rule on the effect of stability of Micro-grid.

Based on the result of SP survey, the transfer problems are classified and analyzed in detail. Then this paper conducts research on the passenger demand for metro transfer system. By using the Multinomial Logistic Model, the transfer impact factor is analyzed which could provide basical support for the improvement, planning and construction of public transit transfer system.

An on-line detection system, which detected for µg/L level of iron, combined the automatic concentrate device and o-phenanthroline spectrophotography. The improved method has four innovations: the automatic concentrate device, the airtight structure of storing ammonia, a temperature sensor controlled the action of the rotating and dumping, an electronic balance with magnetic stirring to control the coloration process. The detection limit for iron was 0.717μg/L, the sensitivity of the improved method was 0.020. The obtained results by using the improved method were in good agreement with those obtained from graphite furnace atomic absorption spectrometry.

This article aims to improve the accuracy of gas flow measurement of cone flowmeter and get a high-precision expansibility factor calculation model with wide applicable pressure range and different upstream side pressure. The experimental research was based on the DN50 and DN100 two sets of V-Cone flowmeter designed by Tianjin University. As the standard gas flow facility by means of critical flow venturi nozzles was insufficient supply capacity and poor pressure stability in positive pressure method, the experimental data obtained from standard gas flow facility by using negative pressure method was used to fit out the V-Cone flowmeter expansibility factor calculation model --TJU-2012 model. The model was tested with the experimental data obtained from the standard gas flow facility and compared with other four cone flowmeter expansibility factor calculation models, its maximum relative error was better than 0.9% and square averaged root error was better than 0.6%, both of them are the least.

This article discusses how and why the wet gas metering overreading produce for a standard Venturi tube by analyzing the influence of the key parameters of X parameter, the Froude number and pressure. The adopted multiphase model is DPM. The results of simulation are compared with the experimental results of National Engineering Laboratory. The maximum relative error of the predicted overreading from simulation is 5.14% and the average relative error is less than 2.8%.

The length variability of telescoping heavy hydraulic trailer wills casue friction and sliding, increasing drag torque and power consumption of steering, moreover, and reducing the security and reliability of steering, so the new type follow-up steering system is designed and studied. In order to reduce the turning radius and tire wear, the adjustable steering wheel structure and double front axle mechanism are designed. On this basis, the theoretical analysis of the steering system is carried out, and the mathematical model is established. The minimum error of actual and ideal angle is regarded as the optimization goal of pure rolling condition, and the simulation optimization and experimental research is done. The results show that: the steering structural optimization is feasible, the performance is optimal on the condition that the actual and ideal angle valves of inside and outside wheels of each axis are approximately equal in turning process, and can reflect the advantage of new follow-up steering system in lowering power consumption, improving product life cycle and other areas.

The smelting factory of Dexing Copper Mine is separated, so mine stripping material and low grade ore yards have huge impact on the environment. For a variety of reasons, the efficiency of operation of the environmental protection facilities in Dexing Copper Mine area was so low that all the acid wastewater was not treated well before discharge. This can lead to a problem that extracting copper and other metal mineral from the low grade ore in the waste stone, and also produce acidic wastewater and heavy metal pollution. Finally, the wastewater discharge into the Dawu River has made huge impact on water, soil, ecological environment. Based on the mathematical model of DGH, this paper analyzed the soil samples of Dexing Copper Mine in the Dawu River domain by the method of successive extraction. The results reveals the DGH characteristics of Cd element in the soil of downstream Dawu River. Cd element in the soil of downstream of Dawu Rive tends to shift from TRCP-Cd (total releasable content of Cd element) to TCAS-Cd (total concentration of active species of Cd element). The critical point of outbreak is TRCP=185.90 ng/g. 36% of the samples of downstream Dawu River oversteps the critical point of outbreak, making it possible to break out. Meanwhile, the analysis of DGH of Cd element is of great significance to early-warning of soil heavy metal pollution and improvement of ecological environment in the study area.

This research based on a new type of Double-cone flow sensor, using computational fluid dynamics (CFD) method and orthogonal experiment to investigate the influence of key geometric factors, such as fore-and-aft cone angle, equivalent diameter ratio and channel flow length, on discharge coefficient, discharge coefficient linearity and relative pressure loss of double-cone flow sensor, and finally predict the best optimal match of these geometric factors. The turbulence model is RNG and the medium for simulation is water. After the simulation, a special device for calibration was set up to verify the computational conclusion. The results show that the biggest deviation of simulation on discharge coefficient linearity and relative pressure loss are less than 0.4% and 1.2%, the results simulated by CFD are in good agreement with that by experiment.

Datasets of metabolomics of multi-group are becoming increasingly complex, hard to summarize and visualize. Hierarchical Modeling makes the data dimensionality reduction and interpretation much easier by principal component analysis (PCA). Dose-response curve is drawed with the principal component score values. As an example, dataset from Ma Xin Shi Gan Tang (MXSGT) water extract administrated rats plasma collected by LC/MS/MS was used to demonstrate this method. As a result, Hierarchical Modeling based on PCA was proved to be an effective, time saving method for data purification.

According to the new kind of the upper arm mechanism of the slag pot carrier, optimization design, simulation and experimental research are carried out, in which the combination of conventional design, three dimensional virtual design and experimental study are applied. The motion law of multi-segment arc slide way of main arm is given by means of researching the motion process of slag ladle in the main arm slide way. The functional relationship among the internal parameters of the arm mechanism, and between load force and arm movement is revealed by studying kinematics of mechanism and dynamics law of the upper arm mechanism. The finite element analysis of the upper arm mechanism is carried out to get the weak links of structure strength, and then the improvement solution is proposed. After experiments, the method correctness of optimization and design of upper arm mechanism is testified by the coincidence of the trial results and experimentation results.

Propylmethyl cellulose monoester of maleic acid (MAPMC) was synthesized with Propylmethyl cellulose and Maleic anhydride. A modified polyether-type superplastizer (PES) was prepared from ally polyoxyethylenether, Maleic anhydride, acrylic acid and MAPMC through a free radical polymerization. MAPMC and PES were recorded by FTIR. The fluidity of cement paste were investigated, the hydration process of cement for PES were characterized via Hydration Heat Tester. The results indicate that PES superplastizers can improve the fluidity of mortars and more capable of preventing slump loss, the hydroxy group of PES has no negative impact on cement hydration .

On the base of introducing the principle of the brake system of mine dump truck,the in fluence factors of the brake performance are analysed.In order to further reduce the brake distance to meet the requirements of actual use,the improvement plan is presented for brake system opti mization and the field test is made.The results show that the brake duration of the brake system is re duced after the optimization and the performance is improved which is of great practical significance.

Transfer print is a new industry in China. There’s a big difference from others, especially transfer print in metal surface. It is hard to control. This paper discusses the pre-exposure time’s influence on the performance of the plate. The results show that the resin plate of 500s is ideal while the making time is 210s, 320s,410s and 500s respectively.

This paper reviews the present situation of research on earthen architecture sites protection in China from the diseases of the earthen architecture sites, reinforcement technologies and materials, non-destructive testing technology and seismic stability reinforcement, and points out the main existing problems. The author holds that China should carry out the top design of the protection research topics as soon as possible to identify the core scientific problems and strengthen the cultivation of the research team; construct the earthen site simulation laboratory in field to research the disease mechanism in a large scale from multi-field coupling analysis; start the scientific research work on the traditional reinforcement materials and techniques and emphasize the application of the traditional reversible reinforcing technique; establish the post evaluation system on the reinforcement effect and make the long-term tracking of the protective effect of the existing reinforcing projects to put an end to the protective destruction; supports the development and application of the non-destructive technology in the field of heritage preservation.

The paper introduces the principle of multi-channel voltage pulse testing scheme based on Lab Windows/CVI. 32 channels of a control system are synchronized acquired through a PXI module NI 6259 and displayed on the virtual instrument interface developed with CVI. The paper illustrates the process of synchronized-selecting more detail in figures and presents a means of how to transform a datum matrix come from NI 6259 to another one which can be calculated and programmed conveniently.

This study provided quantitative analyses about the influence of phasing sequences and the impact of intersection spacing. A large number of signal system scenarios were randomly generated to represent the real-world traffic systems. Based on simulation result, it was concluded that Leading and Lagging left turn phasing were more likely to be involved in progression bandwidth solution of signal systems with randomly distributed spacing. And the number of signals has significant impact on bandwidth attainability. Further conclusions were drawn from the fitting curve that it is impossible to obtain any two-way bandwidth solutions when more than 16 signals were involved in the system.

The thrust cylinder is one of the most important components in thrust system of the shield machine. The enormous thrust force and radial load makes the cylinder work under bad environment. In this paper, it uses nonlinear finite element method to simulate the thrust cylinder structure of a type shield machine. From the simulation results, the contact stress distribution of the oil cylinder guide sleeve and the deformation of the piston rod are discussed, and then the way to reduce the stress concentration is proposed. It provides the theory basis for the design and check of the thrust cylinder.

The acetochlor residue in the tobacco cultivated soils was inclined to affect the growth of tobacco. In this study, regarding the acetochlor as the inorganic salt medium with the sole carbon source, we obtain the acetochlor-degrading bacteria from the tobacco cultivated soil through isolation and screening, numbering as CSUFTM78. Under the view of the microscopy, the bacteria has a rod shape and no spore with the size of 0.8 ~ 1.5 × 0.4 ~ 0.6μm; in the medium, the colonies are opaque, white, round, convex with neat edge and moist and shiny surface. Then determine the concentration of acetochlor which was directly added into the liquid medium and the phote-absorbance of strain number using UV spectrophotometer. The results indicate that the strain CSUFTM78 can grow in the inorganic salt medium which regards quinclorac as the sole carbon source; besides, the degradation rate was up to 38%. By determining the 16S sequence of CSUFTM78 strain, the homology of GENBANK in BLAST reaches more than 99% with Stenotrophomonas maltophilia (HQ185399). By constructing a phylogenetic tree, strain CSUFTM78 and S. maltophilia were integrated into one with the confidence of 100%. Combined with the morphological characteristics of strains, we identify the CSUFTM78 as S.maltophilia and the results can provide both strains and theoretical basis for degrading the acetochlor residual in tobacco cultivated soil using microorganism.

Artificial boundary is an important part of finite element calculation model. Based on finite element method, this paper presents substructure condensation elements to simulate far field boundary. As most dynamic responses are focused on ground surface, substructure elements’ internal nodes are condensed and only keep the nodes on the ground surface to maintain the accuracy of scattering wave transmition. According to the example of verification, if the related parameters are chosen properly, the effect of substructure condensation boundary is guaranteed.

This paper focuses on network management software on the computer a number of issues including the commonly used network management software, network management software applications, user-based network management software, network management software of different characteristics of specific network management software attention to such matters, as well as the development trend.

Now thin coal seam mining technology and equipment falls behind and the researches on hydraulic support is not enough, this paper introduces the structure and design characteristics of hydraulic support of thin coal seamm, systematically describes the automatic control function, and establishes simple planar models of thin coal hydraulic support. Successful application of the support provides methods and experiences for design and manufacture of thin coal seam hydraulic support.