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The method of high temperature physical vapor transport (HTPVT) is an available approach to prepare silicon carbide (SiC) ceramics with high density and high purity. In the present work, α-SiC (6H-SiC) and β-SiC (3C-SiC) powders were used as starting materials respectively to fabricate SiC ceramics with HTPVT process, and the effects of starting materials on nucleation, density, microstructure and mechanical properties of SiC ceramics were investigated. It showed that at high temperature, the decomposition rate of β-SiC was higher than that of α-SiC, and at the initial nucleation stage, the average grain size of SiC crystal obtained with β-SiC starting materials was smaller than that with α-SiC starting materials, because higher vapour pressure of gas phase which decomposed by β-SiC starting materials facilitated nucleation and growth of SiC grains. Density of the resulted SiC ceramics using α-SiC and β-SiC as starting materials was 3.16 g·cm-3 and 3.17 g·cm-3, indicating close values, while, using β-SiC as the starting materials, the grain size was smaller, consequently, the flexure strength was higher. Increasing growth temperature from 2200°C to 2300°C, the densities and the flexure strength of the SiC ceramics using either α-SiC or β-SiC were decreased.

It is an inevitable phenomenon that flash is generated in the process of hypervelocity impact. The research on impact flash is of important significance for assessing the collision between space debris and spacecraft, identifying the material properties on the surface of planet, evaluating the damage of weapon system. A measurement system was built in order to acquire flash spectrum ranging in wavelength from 200 to 1100nm. The relationship between flash intensity and impact velocity was studied. The spectrum consists of line spectrum and continuous spectrum. Line spectrum mainly concentrates in the range of 200-500nm. The spectral lines of the elements were identified. The strong flash happens within 2.2ms after beginning to impact. In addition, the electron temperature of plasma produced in hypervelocity impact is calculated by spectral method, and compared with the temperature measured by Langmuir three probes.

The effect of high-k material on gate threshold voltage for double gate tunnel field-effect transistor (DG-TFET) is studied in this paper. By physically derived the model of threshold voltage for DG-TFET, the quantitative relationship between threshold voltage and gate length is also discussed. It is shown that the proposed model is consistent with the simulation results, and can also easily predict the improved performance on the gate threshold voltage when using high-κ dielectrics and the limited effect on gate threshold voltage when changing the gate length.

This paper presents a physical-based model for accumulation PMOS capacitor based on strained-Si/SiGe material. With this model, the physical mechanism of the “plateau”, observed in accumulation region of the C-V characteristics of the strained-Si(SSi)/SiGe PMOS capacitor, is studied. The results from the model show excellent agreement with the experimental data. The proposed model can provide valuable reference to the strained-Si device design and has been implemented in the software for extracting the parameter of strained-Si MOSFET.

Since external loads affect the sealing performance of bolted flanged joints, this paper calculated external loads of bolted flanged joints by using CAESAR II software and evaluated the effects of external loads on the sealing performance from the viewpoint of changes in contact gasket stress and flange rotation by using ANSYS software. The FE results showed that the contact gasket stress decreases a lot at the tension side and increases a little at the compression side. The paper also evaluated the stress distribution in bolted flanged joints subjected to external loads. The results suggested that the flange rotation and the overall stress increased compared with that of flange without external loads. External loads can induce unexpected leakage and strength failure of the bolted flanged joints during operation.

Gear shaving machining is the one way of gear finish machining; this machining processing is applied in the gear manufacturing widely because of its high efficiency and low cost. Due to the use of standard involutes gear shaving cutter for shaving, the work piece profile nodes occur with varying degrees of "concave" phenomenon. This profile not only affects the gear transmission accuracy, but also can increase the transmission noise, shorten the service life of the gear. In this paper, by using ADAMS software analysis tool, the shaving cutter gear the non-backlash meshing process contact simulation analysis, reached along the tooth profile curve of the contact pressure distribution results. And in the ADAMS environment Post / Process module, in order to meet the needs of the whole tooth profile curve approach contact pressure as the goal, the shaving cutter gear meshing of the maximum contact pressure was carried out based on the experimental design optimization, which conducted the tooth profile modification.

With the construction and development of urban rail transit, Geographic Information System (GIS), a high performance computer based tool is playing a critical role in research and application of the integrated information management. Through the characteristic analysis of the urban rail transit construction situation and operation status, the paper establishes different geographic information data layers including subway lines, stations, construction schedule, quality risk, operating system and emergency resources. Then, it applies the GIS software and service to realize data display, query and analysis with the corresponding data system, knowledge discovery, and algorithm model. Besides, the paper particularly describes the function application cases of GIS technology in many aspects of urban rail transit, which shows that it can improve the management level and safety quality in different stages.

The paper presents numerical simulation of the vortex in a submersible axial flow pump impeller using OpenFoam code. A mixture assumption and a finite rate mass transfer model were introduced to analyze vortex. The finite volume method is used to solve the governing equations of the mixture model and the pressure-velocity coupling is handled via a Pressure Implicit with Splitting of Operators (PISO) procedure. Simulation results have shown that the cavitation may occur on the lower portion of impeller suction side. And the blade channel vortex will be formed in the impeller. It can induce the pressure pulsation in the impeller and can result in reduced efficiency of the submersible axial flow pump.

In order to study the application of Weibull distribution in cable partial discharge pattern recognition. We apply a 10kV 30m XLPE cable for this study. Then design four kinds of typical artificial defect model and analyze each of defect model’s discharge pulse signals. Finally, estimate the Weibull distribution of signals by use of the maximum likelihood method. The results show that Weibull probability distribution is similar to partial discharge amplitude distribution, the shape parameter β can be used to identify different types of discharge.

The paper presents the numerical analysis of erosive wear on the guide vanes of a Francis turbine using CFD code. The 3-D turbulent particulate-liquid two-phase flow equations are employed in this study. The computing domain is discretized with a full three-dimensional mesh system of unstructured tetrahedral shapes. The finite volume method is used to solve the governing equations and the pressure-velocity coupling is handled via a Pressure Implicit with Splitting of Operators (PISO) procedure. Simulation results have shown that the volume fraction of sand at the top of the guide vanes is higher than others and the maximum of volume fraction of sand is at same location with the maximum of sand erosion rate density. The erosive wear is more serious at the top of the guide vanes.

Energy is the basic industry of the national economy, the social and economic development. It plays a very important role in the improvement of human living standards. However, in the actual planning process, a lot of the energy system complexity and uncertainty of information exists, the traditional energy model does not reflect this characteristic. Therefore, this short paper will make a brief introduction of the uncertainty of the Energy System allocation model.

In this paper the digital watermarking algorithm deep into the field of integrated circuits combined with the JPEG image watermarking processes and SOPC technology, Verilog HDL language is used to design and implement of a reusable JPEG decoder IP core which can be embedded, realizing the JPEG decoding on FPGA platform and further completing the watermark embedding. The JPEG decoder is tested through the Modalism simulation software and would be revised until the simulation results become correct. Finally, the Altera development board EP2C70F896C6N of CycloneII series is used to complete the system design. The results prove that the system can run well, the program which can obtain a larger increase speed in exchange for consuming a little hardware resource does work.

This paper outlines the development trend of current tobacco logistics warehouse automation and discusses the process and its subsystem of box type automatic stereo warehouse. The subsystem includes a drill packing, turning box feeding, EMS system, image recognition system, RFID bar code system, weighing system, stacker system, expounds the composition and it’s the basic control flow of computer, PLC electric control system. Aiming at the storage tank type wire automatic stereo warehouse operation in conveying line blocking, distribution efficiency low problem, carry out research and analysis, put forward a design scheme of cross platform change direction, change the target of the. From the actual production operation knowledge, this design improves the efficiency of delivery; field test result shows that the design is feasible and effective.

In this paper, we make the kinematics and dynamics analysis of a micro-robotic platform [3] driven by inertial force generated by eccentric masses. We establish the mathematical model and get the displacement, velocity and acceleration relationships of the platform. According to movement and stability requirements of the micro-robotic platform, we get a conclusion that the minimum angular velocity of the motor when the platform moves and the maximum angular velocity of the motor when the platform jumps.

This article carries on a research about spreading and imitating based on network modal of dynamic, complex and comparing various Agents. The Agent regarded as drug complex network nodes and combine Agent itself functions. Propose a dynamic complex network technology combined with Agent simulation model based on fuzzy cognitive map to study the spread of HIV. Using fuzzy cognitive map design with independent learning ability node agent based on personal emotion and cognition, agent considers the individual perception of the epidemic of surrounding environment, social discrimination, legal constraints strength, national testing and treatment, free needle exchange extrinsic and intrinsic factors in the environment of individual course, emotion, etc., Under the combined effect of individual values ​​derived drug fuzzy cognitive map. Develop individualized decision rules to circumvent virus. This article studied the impact of fuzzy cognitive and social discrimination and legal factors on HIV transmission.

Steady-state magnetic field superconducting magnet power adopted double-inverse-star thyristor rectifier solutions, it is a typical non-linear load which will bring great reactive power impact and harmonic pollution at runtime. In this paper, according to the scheme of scientific facility chain-type high voltage active power filter (APF), a three-grade voltage balance control of capacitor method was proposed. Considering the non-linear characteristics of APF, we using fractional order PI controller instead of ordinary PI controller. The solution of fractional order calculus is realized based on the improved Oustaloup algorithm. Finally, the working effect of fractional order PI controller and ordinary PI controller are comparative analysis through simulation and experimental results, the results show that the DC voltage balance control strategy used in this paper is correct, and has a certain reference value.

Pyrolysis behavior and kinetics of walnut shell were investigated using thermogravimetic analysis in this study. It was shown that kinetics parameters and model of the walnut shell pyrolysis were determined by the relevant parameter of kinetics calculated using Achar differential and the Šatava-Šesták integral methods. 3D Diffusion model (Z-L-T equation) was fitted to walnut shell pyrolysis mechanism with activated energy from 184.08 to 196.88 KJ/mol.

With the development of our society, electronic devices, such as laptops, tablets and mobile phones become increasingly widespread. An accompanying problem of this is the increase of theft aimed at these devices. Even though the proper administration and policy plays an important role to mitigate this crime, they still occur ubiquitously. Therefore, for the sake of eliminating this crime, not only the aspects of administration, policy and legislation should be enhanced, but also the corresponding techniques need to be reinforced. In fact, technology plays a dominant role in preventing crimes. In this paper, a conceptual design of an anti-theft alarm system based on antenna array and wave transmission models will be introduced piece by piece. By implementing a series of electronic components embedded into a protecting wireless network, the location of the protected object can be detected in real time. Once a theft occurs, the computation center will instantaneously obtain the data related to this behavior and assess its authorization and then determine to report or ignore it. This alarm system is specifically suitable for use in public places, for example, libraries, cafes, and holiday villages.

This paper presents a technique for processing Terahertz radar reflector by SPDT (Single Point Diamond Turning) based on LODTM (Large Optics Diamond Turning Machine). This technique applies single crystal diamond cutting tools for ultra-precision machining, and thus could obtain high-precision optical mirror, which could be used as the Terahertz radar reflectors. An experiment for aluminum sample had been done to demonstrate the availability of the technique, and a pair of Terahertz radar reflectors were obtained. The precision of the reflectors, detected through precision coordinate measuring technology, was better than the designed requirement. The experiment results showed that Terahertz radar reflectors generated by deterministic ultra-precision machining technique based on LODTM would have advantages in figure accuracy and roughness and so on, which could be helpful to improve the precision and low the cost of Terahertz radar system.

The life cycle of a road engineering usually contains multiple stages. It starts from design, through the construction, usage and damaged to discarded. Early disease water damage of asphalt pavement has great influence on the service life of road surface. Through analyzing the mechanism of water damage and summarizing the main forms of water damage, this paper puts forward the reasonable distribution of asphalt mixture and the good rigidity relationship between base and surface, which is the key factors to avoid water damage. We analyze and summarize the advantage of drainage asphalt pavement in the prevention and control of water damage of asphalt pavement in order to apply it in the practice of engineering.

In system of cetyltrimethylammonium bromide (CTAB), tetraethyl orthosilicate (TEOS) and sodium hydroxide, the mesoporous sieves MCM-48 with hetero atom could be synthesized by adding different aluminum and titanium sources. The results showed that M41S family of hexagonal (MCM-41), cubic (MCM-48) and lamellar phase (MCM-50) could be synthesized respectively through hydrothermal method by adjusting the alkalinity in synthesis gel exactly.

In recent years, saliency detection has been gaining increasing attention since it could significantly boost many content-based multimedia applications. In this paper, we propose a visual saliency detection algorithm based on multi-scale superpixel and dictionary learning . Firstly, in each scale space, we extract the boundaries as the training samples to learn a dictionary through sparse coding and dictionary learning methods. Then, according to reconstruction error of each superpixel, the saliency map is generated for each scale of superpixel. Finally, some saliency maps from different scale spaces are fused together to generate the final saliency map. The experimental results show that the proposed algorithm can highlight the salient regions uniformly and performs better compared with the other five methods.

With the rapid development of the city, the construction of underpass of adjacent subway tunnel will have influence on the safety of subway operation. Base on underground pedestrian passage engineering, the complex construction conditions of oblique crossing-over subway running tunnel for A section channel is considered, plane strain finite element simulation analysis for the excavation and support and secondary lining construction of A section channel are conducted, and two kinds of construction conditions of adjacent and crossing subway tunnel for A section channel are simulated, the influence of the construction of A section channel on adjacent subway running tunnel is also analyzed. The results were shown that the maximum floating upward value is within 1mm and almost no lateral displacement during the construction of A section channel. which meet the requirements of urban rail transit safety operation, and the basis for advanced control of underpass construction is provided.

This paper puts forward a classification method of imitating the human eyes to recognize image as a whole which combined chaotic neural network and the Empirical Mode Decomposition (EMD). The method takes the individual of weeds plant as the research object and utilizes the chaotic neural network, the EMD, Teager energy operator and cluster analysis technology comprehensively. Firstly take the two-dimensional gray image matrix as the chaotic neural network weight matrix directly. Use the chaotic neural network with n neurons expression to iterate and get the one-dimensional output curve. Secondly, make the EMD decomposition for the curve and get the corresponding intrinsic mode function (IMF) curves. Then make the Teager energy transformation for each IMF component and get the average Teager energy. Finally use the fuzzy clustering algorithm to cluster analyze and get the clustering results. It can realize the classification of different categories of weeds through analysis and contrast the results with the original images. The experiment proves the effectiveness of the proposed algorithm for classifying weeds, and it is a universal new method of weeds classification.

Firstly, a model is established in Pro/E and imported into ANSYS. Static analysis is done through imposed corresponding boundary condition and loads in the condition of fully load. And then, testing its strength can meet the requirements. At the same time, the modal analysis of the third to the tenth steps is carried out and gets the nature frequency under the driving axle housing’s Free State. The vibration performance is analyzed at last.

Under excitation of high-voltage pulse electric field, the deformation vibration of droplet in oil was very important to electro-dehydration of emulsified oil. So far, the theoretical calculation on vibration of droplet was scarcely studied. In order to calculate the vibration of droplet, the forces acted on a single droplet needed to be analyzed, and the vibration kinetic model of droplet needed to be established. The model was resolved by method of harmonious wave balance. It was found by analysis that the resonance of droplet might occur. In the experiment, the results approximated to that of model calculation. So it was verified that the model could efficiently calculate the vibration amplitude of droplet.

In order to study the impact of mechanical properties of aluminum alloy that is added into carbon powder, the aluminum alloy with carbon powder were melt and test bars were cast. The mechanical properties were tested by a tensile tester, the fracture morphology were observed by SEM and the morphology of material surface and composition were checked by SEM and EDAX. The results showed that: several slip platforms were observed during bar stretching and the longer slip platform is better elongation, so the ductile of alloy was improved obliviously after adding carbon powder. Microscopic studies showed that the aluminum alloy system has been infiltrated by the carbon powder and some stable compounds were formed in the alloy systems. Overall, Carbon is added can effectively promote the toughness of the aluminum alloy and improve the mechanical properties to some extent. Keywords: Carbon powder, Cast aluminum alloy, Slip platform, Toughness

In this paper, authors made contrast with the three finite element methods in analysis accuracy and usability .Those are all based on the structural analysis of mining excavator arm. The first fem is using UG solid modeling capabilities to create model .The finite element model is generated by UG_ANSYS, including setting the loads of material properties and boundary conditions ,also loading work. The process is called preprocessing completely .Then export a“. inp” file,after that, imported that file directly into ANSYS software for solving. The second one is to import solid mode created in UG into ANSYS software directly ,then take pretreatment and solution accordingly.The last one is using UG modeling and UG NX NASTRAN (the finite element analysis function) for structure analysis. It is concluded that using UG completely pretreatment of ANSYS analysis method and UG NX NASTRAN method feel more convenient to operate it with the high analyze accuracy,with the two methods , designers can modify mining mechanical arm weak positions more easily.In turns,they can improve the designing level of physical prototyping.

Six degrees of freedom in this paper, by using the ADAMS software to realize the industrial robots can make any saddle trajectory simulation, and trajectory parameters, and it is easy to control the generated trajectory of the saddle shape, size and spatial position,which will improve the efficiency of the industrial robot simulation. The method of complex space curve simulation is generic, and can test the coordinate axis displacement, so the executing agency for the actual factory to avoid movement interference has a certain significance.

With the surface materials of cold region buildings as the research object in this paper, a study on the changes in the color of surface materials in the cases of discoloration, fading and yellowing is made. The changes in the chroma, brightness and hue of visible colors in the case of the use of different building materials are analyzed. The results show: the brightness increases with an increase in the time of exposure, chroma decreases with an increase in time, chromaticness declines fastest and the changes and attenuation of hue are the slowest.

Al-W alloy billets were produced by powder pressing at room temperature and subsequent hot pressing. Quantities of billets were compressed at constant strain rate and temperature with 60% height reduction on Gleeble-3800 thermal simulation testing machine to study the plastic flow behaviors of the test alloy. The temperature of the compression processes ranged from 450 to 570oC. The strain rate was varied between 0.001 and 1s−1. The regularity of flow stress for the test alloy varied at elevated temperatures was studied. The activation energy during hot deformation is 757.943 kJ/mol by calculated, and the Arrhenius constitutive relation model was established. Keywords: Al-W alloy, powder metallurgy, thermal simulation, constitutive model

Soybean wastewater is a kind of nutrients wastewater. Using yeast to treat this kind of wastewater can not only degrade high concentration organic pollutants, but the yeast cell itself also can be harvest and realize the resources recycling. In this work, the feasibility and the optimal conditions of using yeast to treat soybean wastewater were investigated. Results showed that the initial COD and hydraulic retention time were the critical factors influencing COD degradation. Under 28 °C and with the initial soybean wastewater of 4800 mg/L, usingCandida utiliswith 20% of inoculums dosage could realize the higher reduction of the concentration of COD. And after 18 h’s treatment with rotating speed of 160 rpm, the COD removal could reach to 90%. The yeast wastewater treatment technology has the prospect of resources recycling. Besides, the pH value is very important for yeast to treat soybean wastewater.

The paper carries out the finite modal analysis of a Semi-trailer frame and obtains the modal parameters such as frame natural frequency and vibration mode. It also compares the modal analysis results with the excitation frequency effect caused by the road on the frame, the conclusion supports a reference to improve the frame design.

The infrared theodolite is unable to realize the practical problems of star school, put forward a set of indirect detection method for measuring accuracy of photoelectric theodolite, This method not only solves the infrared theodolite test precision,but also can be convenient for full visual field and a full range of accuracy evaluation of equipment.

This article introduces the operating schematic of the ABS. Based on its working characters, an ABS testing bench is introduced. The main parameters of the testing bench are also designed. Its validity and feasibility are proved by modeling and the fem simulative analysis.

Statics is set up on the basis of 4 axioms of statics. Although these axioms are distillate and summarizing of the accumulated humankind's experience in long-range production and life, introduction of these axioms to statics seems a bit abrupt, especially the critical axiom "resultant of two forces" far fetched. This article was an attempt to present the embodying description of the effect of force and force system, based on the nature of effect of force and the equivalent and equilibrium of force systems. On this basis, theorem of two forces resultant and the theorem of two forces balance were proved, and the theorem of force systems equivalent was brought up. A new framework of static equilibrium system was built up to try to make a more perfect and more reasonable description for static equilibrium.

In this paper, a simulation model for the propagation of transformer PD pulse has been constructed,and the propagation of PD in a real substation were investigated. We also studied the frequency characteristics of currents at different detection positions, and the influences of substation network are analyzed in aspects of system resonant frequency. The optimal detection position and the optimal measuring band are proposed. The results show that, the calculated range of substation network and capacitive apparatus play the key roles in impedance characteristics.

Localization technology is enabling technology for wireless sensor applications. In order to improve the localization accuracy of wireless sensor network node, this paper proposes a mobile anchor node localization based on a layered approach. First area for wireless sensor networks slicing. Each layer consists of a number of equilateral triangles. Anchor nodes in each layer moves along the edge of the equilateral triangle to locate unknown node. After receiving the position information of the anchor node, unknown node to determine their own position by the triangular positioning.

Electrodeposition method was applied to recover copper from the simulation of copper-containing electroplating wastewater. Stainless steel plate is used as the cathode and the anode is made of titanium plate coated with RnO2+IrO2, titanium mesh coated with RnO2+IrO2 or stainless steel plate. The electrode potential of copper in electrolyte was calculated, and the effect of initial concentration of copper ions, temperature of electrolyte, voltage, electrode spacing, initial pH value and additive concentration on the recovery of copper was studied in detail. The experimental results showed that the proper anode is titanium plate coated with RnO2+IrO2.Under the condition ofinitial concentration of copper ions 25g/L, temperature of electrolyte 40°C, voltage 3.8V, electrode spacing 25mm, initial pH value 3.60, additive concentration 7.1g/L,the recovery rate of copper can achieve 99.4% and the current efficiency can achieve 88.5%.

Stator winding inter turn short-circuit fault is one of the most common internal faults of fault-tolerant machine, which can disconnect the fault phases and keep operating correctly in the event of a failure. Stator winding short-circuit fault model is established through analysis. Based on finite element method, the high-power density fault-tolerant machine internal magnetic field simulation and analysis is implemented using Maxwell2D and induced voltage frequency spectrum is analyzed by FFT method. The characteristics of stator winding short-circuit faults are summarized, which lay a solid foundation for fault-tolerant machine earlier faults prediction and winding switching.

In order to improve the cutting efficiency of abrasive waterjet (AWJ), the relationship between pre-mixed AWJ cutting depth and pressure was experimentally studied. Then, through analysis of the cutting results, the topographic characteristics and formation mechanism of the cut trough faces were investigated. Moreover, through comparing the effects of different jet pressures on the topographic characteristics of AWJ cut trough faces and the SEM analysis of the cut trough faces at different pressures and depths, the effects of pre-mixed AWJ cutting mechanism on the characteristics of cut trough faces were investigated, and the characteristics of the trough faces of metals cut by pre-mixed AWJ were analyzed.

This paper studied the time-domain waveform characteristics of diesel engine cylinder head vibration. The relative relationship between the various explosions of diesel engine were analyzed and compared. Seven criteria were proposed under which to achieve the time domain waveform peak identification in the absence of TDC signal. According to the criteria computer algorithms for the time domain waveform peak identification were given. The method can reduce the vibration diagnosis system using request such as can achieve misfire fault diagnosis in the absence of TDC signal.

It is high difficult to control the underwater welding because of the effect of water and the leak proofness of the weld devices which is a troubling problem. In this paper, a DSP-based automatic seam tracking system for underwater welding is designed. This system has the advantages of simple hardware structure, low-cost, rich function software, friendly human-machine interface, and easily realizing. And the work of this paper can be used for further research in underwater welding seam automatic tracking.

Obtaining narrower kerf and smaller heat affected zone (HAZ) is a difficulty in laser cutting carbon fiber reinforced plastic (CFRP) composites. In order to solve this problem, the experiments used a semiconductor UV laser to cut CFRP have been done and how laser parameters (include pulse power, repetition frequency, cutting speed and direction) influent the width and HAZ of kerf have been achieved. In the meantime, compared with infrared laser cutting CFRP, the quality of CFRP cut by different wavelength laser has been investigated. The results show that owing to CFRP has the characteristic of anisotropy, laser cutting direction is the most significant factor that affects the quality of kerf cut by UV laser. The study also found that owing to high single photon energy, the narrower kerf and smaller HAZ around kerf can be get by UV laser cutting CFRP, nevertheless, it can’t be achieved by infrared laser cutting CFRP.

The residual vibration of cam curves is analyzed. The displacement of residual vibration is computed by Duhamel method. The comparison of the residual displacement between the flexible exponential cam curves, the modified constant velocity curves, the modified trapezoidal curves, and the modified sine curves is done. The residual vibration of the flexible exponential curves is smallest.

First of all, the characteristics of obstacles in military vehicle equipment running simulation were described, and three generating methods, that is, extracting from digital vector map, manual drawing and dynamic generating during simulation, were expatiated. According to the demands, the data structure of obstacles was designed. Afterwards, the spatial overlay analysis of the moving route and the obstacles set, appending and deleting obstacles, and breaking a new path in obstacles were researched respectively.

The objective of this study was to investigate the effects of salinity on power generation and microbial community structure in the microbial fuel cell (MFC). Three two-chamber MFCs (MFC-A, MFC-B, MFC-C) were used to conduct experiments. The MFC-A was operated sequentially using solutions of 0, 20, 40, 60, and 70 g/L NaCl in the anode chamber of the cell. The MFC-B was operated with solutions of 0 and 40 g/L NaCl and the MFC-C with solutions of 0 and 70 g/L NaCl. Results showed that the salinity inhibited power generation in all the MFCs. In the MFC-A, the maximum voltage outputs and CEs decreased from 660 to 130 mV and from 67% to 4%, respectively, with the NaCl concentrations from 0 to 70 g/L. However, the NaCl concentrations did not affect the removal efficiency of substrate (glucose) in the MFC, which reached 100% at the end of every cycle. Moreover, voltages could be recovered to the maximum value (630 mV) within 60 h after replacing the salt solutions with water. With the solutions of 40 and 70 g/L NaCl in the MFC-B and MFC-C, respectively, no obvious electricity was generated after two cycle operations.

In this paper, taking Luoyang city as an example, research the problem of population system based on the entropy method in the urbanization process. First, access to date of statistical yearbook, we choose 8 indexes to construct the evaluation of development level of population urbanization. Then, using the entropy method to determine the weight of each index, a multilevel fuzzy comprehensive evaluation model is built to evaluate on this change between the urban and rural in population system. The results show that the level of urbanization of this city is currently in the conversion process from the second grade to the third.

The CY7C68013 chip of FX2 series products from Company Cypress is used as the bridge between Nios II and the computer. The data communication between the two parts can be realized quickly and stable used the USB 2.0 interface, which made it possible to save the resource on chip. Thereafter Nios II can be set free from the heavy work of data communication. The designation can be used to made a system for data acquisition or image processing based on Nios II which can be used to solve the bottleneck of low speed.

Li-ion battery, with the advantage as small size, large power density, high individual voltage, low self-discharge rate, and low internal resistor so on, substitutes the traditional power battery used in AGV system. In the practical application, Li-ion battery discharge with large current after a period of time, the upper voltage of every cell will be non-consistency, and the power system will work abnormally. In the case, the intelligent management of li-ion battery is designed.Experiment result improves that the system can effectively protect the li-ion battery and realize the energy feedback.