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Pressure vessel is widely used in the industrial engineering. Many materials in pressure vessel are inflammable and explosive dangerous goods. If the accident happens, great harm will be done to the lives and properties of people. Some common methods for studying pressure vessel have obvious drawbacks. 3D laser scanning method uses non-contact measuring method and can directly obtain the point cloud data of the mass surface which can be used to reconstruct any convex surface. According to the advantages of 3D laser scanning method, in this paper, it is introduced to measure the dimensions of flanges in pressure vessel. The experimental results obtained have little errors, which certify that 3D laser scanning method can be used to measure the dimensions of flanges and further study the characteristics of pressure vessel.

Poly (L-lactide) was grafted onto chitosan by ring-opening copolymerization under microwave irradiation in the presence of tin octoate (Sn (Oct)2) as catalyst. The chemical structure and physical properties of the copolymers with different feeding ratios were discussed by FTIR, DTG and X-RD, taking pure chitosan as reference. The results showed that the application of microwave irradiation in the reaction could achieve the copolymer with high grafting percentage in a short time and low temperature. The thermal stability and crystallinity were decreased with the feeding ratio increasing, attributing to the increasing of grafting percentage.

The steady-state mathematical model of Smith-connection three-winding single-phase capacitor motor is established, and the capacitance calculation formula in minimum voltage unbalance condition is deduce .Based on this, by MATLAB simulated program, a operation simulation of Smith single phase capacitor motor that in single-phase 220V power supply and in single-phase 380V power supply is developed. The simulation results agree with the experimental results.

This paper introduces the detecting principle、range of application and interferencerejection of Ultrasonic And UHF Partial Discharge Detection In GIS(Gas Insulated Switchgear).In view of the advantages and disadvantages of ultrasonic and UHF detection,this paper proposesa quick joint detection method, which uses UHF (Ultra High Frequency) method to online detectthe suspected discharge range in real time, adopts ultrasonic method to determine the specificdischarge points, finally through a concrete instance in a 1000KV UHV(Ultra High Voltage)Substation verified the feasibility of the joint detection method.

There has been wide interest in the control scheme of the electromagnetic levitation system due to its disadvantages of nonlinearity and open-loop uncertainty. A typical coil-ball levitation system is used in research. The forces of the ball are analyzed and a dynamic model of the whole electromagnetic levitation system is established. Based on the nonlinear state-space model, the coil-ball system is linearized and then a LQR control approach is proposed. Simulation results show that, compared with conventional pole assignment scheme, the electromagnetic levitation system under the proposed control approach gets a better performance, including smaller overshot and faster response.

Determining the freezing pipe spacing, the freezing reinforcement required range and method, acquiring the development and distribution patterns of frozen soil wall temperature field are the key issues needed to be addressed when using vertical freezing method for the soil reinforcement at shield shaft. Based on the shield launching project of the cross-river shield tunnel of Nanjing subway line 10 and the finite element numerical analysis software, the development and distribution patterns of different distance between freezing pipes of the vertical frozen wall are studied. The numerical simulation shows that, it is feasible to use the numerical model to simulate the temperature field of vertical frozen wall. Decreasing the distance between freezing pipes causes a greater impact on the temperature field. When freezing pipe spacing increases to 0.1m, frozen wall cross-lap time increases of about 1 day. With the freezing pipe spacing increasing, the cross-lap time increases linearly. The temperature of frozen wall decreases with the distance between freezing pipes decreasing, and the strength of frozen wall is more uniform. Results and conclusions form this research may play a useful role to aid designs of similar projects in future.

The impact of the flood discharge water flow from a high dam is rather great on the slab of a plunge pool, and may cause damages to the plunge pool and consequently endangers the dam body safety. Therefore, a reverse arch slab model was established on the base of a study on and a simulation of the rational scale of gaps between the plates of the plunge pool slab. The model was an arch ring containing 7 slabs. The uplift force time history of each slab was measured, and the uplift force power spectrum and probability density were analyzed. The test result shows that the uplift energy mainly centers in 0-15Hz frequency bandwidth, and mostly within 1Hz. It belongs to a low frequency and big amplitude vibration.

In this paper, the generalized projective synchronization for a general class of hyperchaotic systems is investigated. A systematic, powerful and concrete scheme is developed to investigate the generalized projective synchronization between the drive system and response system based on the feedback control approach. The hyperchaotic Chen system and hyperchaotic Lorenz system are chosen to illustrate the proposed scheme. Numerical simulations are provided to show the effectiveness of the proposed schemes.

An automation intelligent electrical distribution terminal unit is designed in the paper, making full use of the super calculation ability of digital signal processors. Whole hardware design and circuit designs, such as power conversion module, relay control module communication and data storage module etc, are discussed respectively in the paper. Researches on the reliability of the intelligent terminal unit are carried on finally. Results show that the unit can operate safely, stably and reliably.

With the conflict between storage space of the ship navigation radar system and large raw echoes data and files, a mixed compression algorithm of the bitmap compression + half-byte compression + Double Huffman compression is presented which is based on the characteristics of the text type data. On the basis of the original half-byte compression algorithm, the method combined with the bitmap compression and Huffman improved compression algorithm. If just using the half a byte compression algorithm, the compression ratio can only be 50%; while using the hybrid compression, the total compression ratio can be up to 75%, which save a large amount of storage resources for ship navigation system, and improve the rate of data transmission at the same time.

Because the attributes of the network data become more and more complex, the useful clustering attributes are increasing greatly. The traditional network data clustering algorithm is sensitive with the initial center of the network data clustering which cause the operation efficiency of the algorithm is quite low. This paper proposes a kind of network data fast clustering algorithm based on fuzzy processing model. The algorithm solves the issue of fixed center in the traditional network data clustering algorithm. The experiment illustrates the algorithm has better clustering accuracy and the convergence speed is quickly.

The global navigation satellite system (GNSS) is an important infrastructure of the space-time positioning; not only plays an momentous role in the building of national defense and national economy, but also the world's major competitive battleground of space powers, space technology and its applications. Accurately grasp the characteristics of the life of the GNSS, redundancy of key components to establish a practical satellite program, is one of the prerequisites of the satellite lifetime assurance measures. In this paper, we build the satellite lifetime grid model based on the satellite key components lifetime degradation models, optimize the key components redundancy design scheme combining genetic algorithm. To guarantee the lifetime of the entire star, optimize the satellites cost, provide the theory support of decomposition and optimization of life indicators for GNSS.

Transport sector is one of the main sources of anthropogenic greenhouse gases (GHG) emissions. Comprehensive countermeasures are needed in cities to mitigate transport GHG emissions. After reviewing green traffic measures that implemented by Shanghai since bidding for Expo 2010, this paper analyzes the achievement that Shanghai has made in carbon mitigation. The results showed that travel demand management and the constrcution public transportation infrastructure promoted by the event played a vital role in promoting mode shift to form public transport oriented traffic system. Carbon emission intensity of Shanghais urban transport declined steadily from 1.66 kg/trip to 1.55 kg/trip. The CO2 reduction attributable to mode shifts amounted to 4.99 million tons. It demonstrated that Shanghai Expo has promoted the city in carbon emission reduction through public transport improvement, new energy vehicles innovation, car growth restriction measures and green commuting initiate.

Water quality of Poyang Lake is facing serious threats with the quick development of Jiangxi Province. Water quality control and pollution prevention of Poyang Lake have become important problems set before Jiangxi Province. To keep good water quality of Poyang Lake, a series of pollution-preventing strategies were studied. In order to prevent point source (PS) pollution, industrial types and layout, management measures and production technique should be improved. Strategies to prevent non-point source (NPS) pollution include four aspects. First is to transform part of NPS pollution to PS pollution by rationally laying out industry system. Second is to construct spatially harmonious and reasonable landscape pattern. Third is to reform conventional agricultural production by using advanced chemical and biological technologies. Fourth is to carry out Best Management Practices (BMPs) and Low-impact Development (LID) by learning and innovation.

This paper will systematically study the different shapes of steels corrosion rate under different corrosion environments through accelerated corrosion test of orthogonal experiment and the corresponding physical tests and electrochemical detection methods. The experimental results show that the corrosion resistance of the deformed bar is poorer than the plain round bar. In the same corrosive environment, its tensile strength, yield strength and elongation decline are more significantly than the round steel, and the change of the elongation is more obvious. Experimental results also show that in the environment which is absence of chloride ion, reinforced is basically with uniform corrosion in previous time, late stage for the development of local corrosion, the mechanics performance index is also present a corresponding positive correlation with the corrosion situation. But the uneven corrosion condition appears at the previous period when it is in the chlorine ion environment. In this condition, the mechanical performance and corrosion situation is no longer in linear relationship, but the trend of rapidly decline. Results of weightlessness rate test confirm that the correlation of degree of corrosion and the mechanical properties.

In order to achieve internal reinforcement of concrete bridges quantitative nondestructive testing, this paper has adopted linear polarization method to test reinforcement passivation in the pore solution of simulated concrete and corrosion current density value in the corrosion process under different external environments and has built calculation model for amount of reinforcement corrosion based on detection signal. That is to say a new idea, which makes the evaluation results more effective, has been put forward to efficiently correspond with reinforcement corrosion ratio with potential signal, and the quantification evaluation for damage of reinforced concrete can be carried directly. It has modified theoretical model and analyzed the error through weightlessness tests. The research result shows that the calculation model after modified can significantly improve the detection accuracy for the actual rate of reinforcement corrosion. CLC: TU528.33 Document code

Short-cut grass and starch were selected as raw materials to prepare environmentally friendly composite by hot-pressing method. Results indicated that short-cut grass and starch were easily mixed uniformly by water medium and adapt to hot-pressing process. Hot-pressing time and hot-pressing temperature influenced the performances of composites. The strength and elongation first increase and then decrease with the increase of two processing factors. Tensile strength and strength at fracture reach 2.3 MPa and 1.2 MPa respectively when hot-pressing was performed at 140 °C for 10 min. The tensile strength is always higher than strength at tensile fracture and the elongation at fracture is always higher than that at maximum force. This indicates that the fracture of composite is ductile fracture. The hardness of composite is uneven. Long hot-pressing time resulted in not too obvious decrease of hardness.

Corrosion of reinforcement is one of the most important factors in causing the damage to reinforced concrete structure and the inestimable economic loss and major security risk to a large number buildings with reinforced concrete structure. In order to overcome the disadvantage of previous service reinforcement which can only be carried out by sizing detection not quantification, this paper puts forward to a new method to evaluate non-destructive quantification of corrosion degree of reinforcement based on the combination of electrochemical detection and finite element analysis, thus the effective corresponding can be produced among reinforcement corrosion rate, potential signal and reinforced concrete structural distortion. The relation among corrosion current density and potential characteristic parameters as well as corrosion ratio has been established. Through the finite element analysis technique and the combination with the case analysis, the relation model between the strain rate of concrete beams and detection signal has been built; the forecasted empirical formula for change of strain value of tested reinforcement has been given And by means of verifying the reliability of model with data of previous experiments, the quantitative calculation of reinforcement corrosion degree has been realized, which lays the technical foundation for the research and development of non-destructive detection equipment of corrosion of reinforcement.

To the question of networked control system with random time-delay in both forward and feedback channels, a new class of Smith predictor combined to Fuzzy PID control is presented. It sets up a new Smith forecast model and designs the parameter self-tuning fuzzy PID controller. The results of system simulation using MATLAB show that the network control system of the proposed scheme has better dynamic and stability, and in the case of model miss-matching has high robustness.

The AT89S52 MCU is the central core of the system which combined with external circuit modules for data processing. Under the stable supply of 5v DC power, the each module can be initialized by MCU, through the serial port communication technology for data exchange. The single serial bus interface technology is used to obtain DHT11 temperature and humidity sensor testing data in the system. Through the MCU data processing, the detected data will be compared with the alarm data which is given by the users. When a given range is exceeded by the detected data, the sound and light alarm is triggered, moreover, temperature and humidity control is performed. Compared with the LCD1602, the advantage of the temperature and humidity remote monitoring system are the simple structure of the circuit, work stability, accuracy and fully suitable for the need of temperature and humidity monitoring system in human living environment.

This design uses GPRS wireless communication technology to achieve remote control of the stepper motor. The system design the software of upper machine by the VC++ based on the TCP/IP protocol. The wireless module SIM300 transfers data to the primary station by its GPRS function. Then the primary station converters the input into differential signal and send commands to slave stations via RS485 and Modbusprotocol. According to the commands, slave stations output the corresponding control signal to the stepper motor. Stepper motor has some protection function when working, such as: acceleration and deceleration and down limit , emergency stop , over-temperature .The result of experiments verifies that the aim of design GPRS-based remote control of stepper motor is realized. It is possible to improve largely both in real-time performance and reliability by using the GPRS wireless technology, it promotes the industrial monitoring and control system more intelligent and informed.

This paper describes the optimization design of prefabricated XPLE cable accessories and presents the formula of the design of stress cone. The finite element method for optimizing the design of the electric stress distribution inside the HV power cable joint and adjusting the length and curvature of the stress cone of this termination is discussed. The relationships between dimensions of stress cones structure and the electric field distribution were obtained.

In this paper, a new kind of Multi-model Predictive Controller (MMPC) is presented. Multiple models switch MMPC with Kalman filter based on neural network optimization was implemented in a DC/DC converter. Multiple models direct switch was used according to the two modes of the Boost-Buck circuit and different loads condition. Kalman filter was successfully added to the MMPC to transfer the optimal state value to MMPC from the output of the DC/DC circuit. Parameters optimization method is also discussed in the paper when the controller was applied to real model simulation. Simulation result demonstrates that the good performance of MMPC compared with single model predictive control and PID control. With the help of high speed FPGA, it is possible to apply this method to hardware simulation.

Wireless sensor networks consist of two kinds of nodes: the anchor and the Agent. The anchor is equipped with special hardware to obtain precise location information and employed to derive the locations of Agents. Due to the resource-limited nature of single sensors, actively participating nodes should be kept to a proper number. Based on an investigation on the trade-off between the localization accuracy and the computation complexity of sensor nodes, we propose a distributed algorithm to select subsets of anchor nodes for localization and analyze this algorithm regarding the energy consumption of every node.

The basic performance and technical characteristics of the prefabricated light-gauge steel inner partition are introduced in the article. And a detailed analysis of its economic is studied by comparing with other inner partition wall materials. The results show that the prefabricated light-gauge steel inner partition not only has good economic effect, but also has high social value.

Thermoelectric energy harvesting is emerging as a promising alternative energy source to drive wireless sensors in mechanical, civil, and aerospace engineering systems. Typically, the waste heat from spindle units of machine tools creates obvious potential for thermoelectric generation. The structure of heat sinks on a thermoelectric generator has a great effect on the output voltage of the thermoelectric generator due to the temperature difference between hot and cold sides induced by heat transfer, so several typical structures of heat sinks are studied under different rotation speed of the spindle. According to the simulation study, the thermal resistance of heat sinks was presented. In the experiment, the output voltages of a thermoelectric generator were measured under different rotation speed with different structures of heat sinks. Experiment and simulation shows that the two pipes structure of the heat sink can help the generator to produce more power.

This paper primary researched the influence of limestone powder on the workability, the strength performance and the volume stability of self-compacting concrete (SCC). Results showed that the workability of self-compacting concrete was improved greatly by mixing proper limestone powder; besides, limestone powder could improve early age strength of concrete obviously, but had little influence on long age strength; the self-shrinkage of concrete increased as the admixture of limestone powder increased. The content of limestone should be capped at 10% and the optimum mix amount is about 7%.

The physi-mechanical performances of geosynthetics were studied by the test on the geosynthetics produced by one factory. Tests of stretching, top-breaking, pierce, tearing, etc. under different materials, temperatures and moistures were done by indoor study, thus studying the physi-mechanical performances of geosynthetics under different conditions. The research shows: the stretching performance of nonwoven textile is better than the woven textile's; The influence of temperature on the geosynthetics is remarkable, it should be emphasized during the construction; The moisture has a little impaction on the mechanical performance of geosynthetics; These achievements provide scientifical data and references for the physi-mechanical performances of geosynthetics, while no further study on the long-term effect, it should be studied in future.

Global navigation satellite system (GNSS)-like the Global Positioning System (GPS) and the future Chinese Beidou system-can deliver very good position estimates under optimum conditions. However, especially in critical positioning scenarios like urban canyons or indoor environments the performance loss would be very high or GNSS based positioning is even not possible. Based on the concept of Cooperative Positioning in acquiring real-time positioning information of mobile robots, GNSS Peer-to-Peer Cooperative Positioning (P2P-CP) technology is proposed to overcome the shortage of GNSS positioning. Terrestrial ranging and communication modular are equipped with GNSS receivers to construct real-time CP network. The terrestrial ranging and communication modular respectively used for distance measurement and communication between nearby GNSS receivers, distributed algorithms are applied to fuse pseudorange and neighbors nodes distance to calculate the nodes position. Current research results of GNSS CP show that this new positioning strategy gets equal or better precision with less time cost compared with Assisted GNSS (AGNSS).

Determining the freezing reinforcement required range and reinforcement method, acquiring the development and distribution pattens of frozen soil wall temperature field are the key issues needed to be addressed when using cup-shaped horizontal freezing method for the soil reinforcement of shield tunnel ends. Based on the shield launching project of the west side of Yixianqiao station in Nanjing subway line 2 and the finite element numerical analysis software, the development and distribution patterns of the cup-shaped frozen soil wall reinforcement were studied. The numerical simulation showed that, after freezing for 30 days, the x = -1 section temperature field evenly distributed around the center tube. And the freezing temperatures within the outer tubes were usually below-20°C. The temperature field circled around the center tube and the temperature gradually increased from the inside to the outside to 0°C within the range of about 1 m outside the outer tubes. The freezing temperatures within the range of 2 m thickness of the cup-bottom in the y= 0 section were usually below-10°C and the temperatures changed from inner to outer significantly until rising to 0 °C at the freezing pipe ends of the cup-bottom. Freeze wall formed firstly in the outer tubes, then the intermediate tubes, and lastly the outer tubes. And the freeze wall closure time that closed cup-shaped frozen soil wall formed was 15 days in this designed freezing method.

The possible reasons of an explosion during the process of filling oxygen cylinder were analyzed in this article. And finding the grease in the cylinder may be the main cause of this incident. Using three kinds of lubricating oil as the experimental grease were experimented in combustion reaction under different pressure of oxygen by the PTGA. The relationship between the increment of lubricating oils' mass, ignition point, combustion rate and the pressure of oxygen were derived from the TG and DTG curve (TG-DTG curve). Experimental results show that the oil oxidation increment increase and the ignition point decrease with the pressure of oxygen escalating, and the higher pressure of oxygen, the lower combustion rate. In addition, the fact was confirmed that the lubricants additives have an effect on combustion characteristics of lubricating oil in high-pressure oxygen.

The principle of carbon materials modification by plasma was introduced in this paper. The studies on application of plasma technology in surface modification of carbon materials were reviewed in three main aspects, namely using plasma to improve the catalytic effect, capacitance and adsorption performance of carbon materials. Moreover, the prospects of plasma technology in surface modification of carbon were also discussed.

In the new era, the reliability technology based on physics of failure (PoF) is playing an increasingly important role in development of electronic equipment. PoF models of electronic products, as the foundation and core of this advanced technology, are the main point of engineering application. With continual scaling of VLSI in electronic equipment, the electric field across gate oxide becomes higher and higher and affects the reliability of semiconductor device greatly. In this paper, TDDB failure mechanism and Physics-of-Failure model was researched firstly. Then the test sample was designed and processed, and the test verification program for TDDB Physics-of-Failure model was carried out to develop the test verification, collect and process test data. Through analyzing test data, the parameters of TDDB model were determined and modified to ensure the Physics-of-Failure model precision and the model could be used in engineering. Based on modified model, the reliability of integrated circuits can be evaluated at designing stage. And the inherent reliability of integrated circuits in electronic equipment could be improved by design optimization to reduce the risk in the process of using.

Physics-of-Failure (PoF) represents one approach to reliability assessment based on modeling and simulation that relies on understanding the physical processes contributing to the appearance of the critical failures. Firstly the connotation and meaning of PoF method were analyzed here, the inherence relation between PoF and reliability was expatiated, the PoF based reliability method and current reliability method based on probability statistics were compared, their differences and relationships were discussed here. Then the application condition of PoF method in reliability engineering in European and American developed country and China were summarized, the PoF based reliability engineering technologies were introduced systemically from several aspects, such as reliability design and analysis, reliability test and validation, maintain and support. Finally, combining with the developing characteristics of military materiel during the new period, some future investigation directions and application foregrounds were prospected.

Based on the principle of the three phase voltage source PWM rectifier, firstly, describes the topology of the three-phase VSR, and establishes the three-phase VSR’s mathematical model based on the three-phase stationary symmetric coordinate system (a,b,c) and two-phase synchronous rotating coordinate system (d,q); then analysis the three-phase VSR’s control strategy, and discusses the feedforward decoupling control strategy of the inner current loop, the outter voltage loop control strategy and the Space Vector PWM (SVPWM) control strategy. Secondly, builds a simulation model, simulates it in Matlab\Simulink environment.The simulation results show that the system has good current waveform of AC side current, high system stability, fast dynamic response speed, and can realize two-way flow of energy, energy feedback, and unit power factor control.

A new control method based on least squares support vector machine (LSSVM) and model predictive control (MPC) is proposed for the control of fermenter temperature. Existing PID control doesn’t consider the model of controlled object, so it tends to bring steady-state error. The proposed method utilizes LSSVM to obtain fermenter temperature’s model and then uses it to implement MPC. The simulation results show that our method has better control performance than traditional PID control

In this paper, A class of third-order nonlinear neutral damped functional differential equations with distributed deviating arguments are studied. By using a generalized Riccati transformation and Kamenev-type or Philos-type integral averaging technique,we establish some new sufficient conditions which insure that any solution of this equation oscillates or converges to zero.

It is very important for connection of between beam and column, connection safety and reliability is premise to guarantee the normal work of the whole structure. Node often bears complex stress which includes compression, bending and shear, so the study of the mechanical properties and ascertained behavior of mechanical, failure mechanism of between beam and column is very important. This paper use finite element analysis software to analyze the node of between SRC column and RC beam which exist in high-rise buildings but relatively few researches at present. Analyzed cracking load-displacement relation and studied on relation of concrete shear strain-section steel wing shear strain and crack load of joint core with different axial compression ratio, According to data of finite element analysis, this paper bring forward formula of crack resistance capacity of SRC column-RC beam joint core, At last compare theory value calculated with formula with test data, there being less error, it indicate the formula is reliable.

A hybrid adaptive genetic algorithm is proposed for solving constrained optimization problems. The algorithm combines adaptive penalty method and smoothing technique in order to get no parameter tuning and easily escaping from the local optimal solutions. Meanwhile, local line search technique is introduced and a new crossover operator is designed for getting much faster convergence. The performance of the algorithm is tested on thirteen benchmark functions and the results indicate that the proposed algorithm is robust and effective.

Tower crane is a widely used lifting machinery which can be produced by several domestic manufacturers. The study on static characteristics of tower crane is widely engaged in nowadays. However, the analysis based on advanced CAE techniques is seldom used. Therefore, this paper uses ANSYS to analysis the characteristics of tower crane and the final results are well validated.

There are numerous difficulties and risks in the construction of river-crossing tunnel of large-diameter metro. How to ensure the safety of the project and reduce the construction risk is the key issue requiring urgent solution. This paper, taking a project of constructing river-crossing tunnel of large-diameter metro as the research background, compared and selected the methods of constructing this river-crossing tunnel. Large-diameter slurry shield machine was recommended to conduct digging construction. Then, possible risks of the selected construction method were analyzed and summarized into two categories: risk concerning the project itself and environmental risk. Finally, corresponding measures to handle the risks were put forward.

In recent years, with the development of intelligent control theory, fuzzy control theory has been applied to automatic control of the crane. This paper designs fuzzy anti-swing controller based on the nonlinear mathematical model of bridge crane, and MATLAB/Simulink simulation was carried out. The Simulink experiment proves that location fuzzy controller and angle fuzzy controller show the good anti-swing effect compared with conventional PID controller. The two controllers not only improve response speed times but also improve control accuracy.

This paper describes the design of monitoring system for coal mine safety constructed by MSP430 and nRF24E1, which has described the structure of the system, working principle, and gives the hardware design of sensor nodes and the software design. This system is used for on-line monitoring of coal mine safety with the character of simple structure, low cost, low power consumption and so on, which will improve the level of monitoring production safety and reduce accident in the coal mine.

An improved understanding of changes in carbon storage of terrestrial ecosystems is very important for assessing the impacts of increasing atmospheric CO2 concentration and climate change on the terrestrial biosphere. Accurately predicting terrestrial carbon (C) storage requires understanding the carbon stock, because it helps us understand how ecosystems would respond to natural and anthropogenic disturbances under different management strategies. We investigated organic C storage in aboveground biomass, litter, roots, and soil organic matter (SOM) in five land-use types (i.e. artificial pasture, AP; natural meadow, NM; corn plantation, CP; temperate savanna, TS; and bush wood, BW) in meadow steppe of Northeast China. The primary objective of this study was to ascertain the impact of different land-use types on the carbon stock. The total C storage (including C stored in aboveground biomass, litter, roots, and 0–100-cm soil layers) did not significantly differ between one and another type among the five pairs (P>0.05), with the exception of AP2-BW pair. The total C storage changes in value varying from 5958.09 g C m-2 for plot NM2 to 11922.87 g C m-2 for plot CP1. The C stored in the aboveground biomass was less than 1177.96 g C m-2, accounting for negligible amounts (-2 for plot BW, CP1, and CP2 to 2032.32 g C m-2 for plot NM3, and it accounted for less than 20% of C storage in the grassland.

In order to make sure a high-accuracy and fast- speed survey, a Soft-sensing model for the roughness of machining surface was built based on the support vector machines using rotate speed n, feed peed vf, and depth of cutting as independent parameters, taking groups of actual machining experiment data as samples.The allowable error ε and the positive aligned c and the kernel function parameter r were optimized by an adaptive genetic algorithm. After being optimized 300 steps, the following results can be gained through the training, testing and application. The average relative error tended to saturation training was 4.0%; the test error was less than 2.6%; the average relative error between the Soft-sensing value for the roughness of machining surface under the numerical control and the test value of the profile and roughness tester for the SV-C3000 super surface of was ranging from 0.4% to 1.25%.

Considering the multiple and complicated driving conditions for tracked vehicles and their structural features, a comprehensive intelligent control method to deal with semi-active suspension was proposed based on the principle of magneto rheological damper. One half of the tracked vehicle suspension system is taken as the research object, where analysis is directed to the vertical amplitude, pitch angle and vertical body acceleration response. And the magneto rheological damper was taken as an actuator, the fuzzy control was taken as feedforward and PID control was taken as feedback. The control system model has been established by using of the complex random road output to simulink due to the condition of MATLAB/Simulink. The simulation results show that it is of good real-time control competence, good robustness and high accuracy, etc. Contrasting to passive suspension, some capability parameters such as the body vertical amplitude, pitch angle and the body vertical acceleration of the semi-active suspension system can had been well controlled by using of the intelligent hybrid control method, for exmple, the root mean square value of vertical amplitude decreased by 37.2%，the root mean square value of pitch angle decreased by 45.2% and root mean square value of the vertical vibration acceleration decreased by 38.6%.

Based on reliability theory on physics of failure, reliability information of electronic products is predicted by modeling and simulation methods. Various engineering analysis techniques are utilized and the product’s reliability is analyzed and designed. Analysis results on an electronic product example show that physics of failure method can find week problems of reliability design, advance prevention measures, mend the design to eliminate potential faults, thus improve the inherent reliability of electronic product ultimately.

As a branch of Utilization of vibration, vibration friction is a type of the most valued applicable technology developed during the later part of the 20th century and still in rapid development now. Since the technology is closely associated with industrial and agricultural production, can create huge social and economical benefits for our society and provide excellent service for human beings, it becomes a necessary mechanism in human production and life. The theory of the vibrating machines has been developed and used widely in this field. In this paper, nonlinear dynamic characteristics of vibration friction system based on vibration pile driver were investigated. According to dynamics theory, the motion equation of vibration friction system was established. For further study of vibration friction mechanism and its application on vibrating machines, numerical simulation of vibration pile-soil system was made. Chaos was found in the process of motion. The conclusion of our research is that vibration can decrease rub and wears between vibrating body and materials and it is very important to prolong the working life of machines and their parts.