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The structure of inertial-type counter flow screen is presented in this paper. It can be proved that the solid wastes with different friction factors and elasticity coefficients can be well separated by inertial-type counter flow screen. The more difference they have in friction factors and elasticity coefficients, the better sorting performance can be achieved. The selection and calculation on the dynamical parameters of inertial-type counter flow screen is carried out. The study provides the theory basis for the design on new-type friction separation equipment and develops new prospects for the application of inertial-type counter flow screen.

The detection of rotor position plays an important role in the motor speed-adjustment system. By analyzing the back-EMF method and its improved methods, we know the amplitude of back-EMF is too small to be detected when the motor run at low speed. A new detection method of rotor position has been proposed in this paper. It detects the zero crossing point of line terminal voltage difference to acquire the rotor position signal after a 90 degrees mechanical angle delay. The amplitude of line terminal voltage difference is large in wide speed range, so the rotor position signal can be accurately acquired in most situations. Simulation results proved that the new method can obtain the rotor position signal exactly in both high and low speed. It meets the wide speed range of motor.

Energy recovery ability is one of the most important ability of the hybrid system. In this paper, we established a simulation model of a 10T hybrid tractor under researching in advisor by the secondary development technology. And then we carried out the simulation which provides many important curves about the energy recovery ability and some other important abilities under the working conditions of 5 peak cycle using the self-adaptive fuzzy control strategy. The results of the simulation prove that the recovery ability of the hybrid tractor satisfy the design goals well.

N5 single crystal was transient liquid phase (TLP) diffusion bonded under different conditions in vacuum environment using Ni-base insert metal. Scanning electron microscopy (SEM) was used to observe the microstructure of the joints. Results show that the typical TLP joint could be divided into rapidly solidified zone (RSZ), isothermally solidified zone (ISZ) and diffusion zone (DZ). The widths of RSZ decreases with the increase of holding time at any established bonding temperature, amount of bulk compounds decrease at the same time. Bonding temperature has a complex influence on TLP joint. High temperature creep rupture tests were performed, results reveal that the sample fractured in the joint interface and the fracture mechanism has been studied.

In this paper, the research status and development trend of titanium alloy/stainless steel joining technology is reviewed. Characteristics and problems of titanium alloy/stainless steel jointing are analyzed. And then advantages and disadvantages of various jointing methods are compared.

The steering quality is one of the most important targets which reflect the flexibility of the vehicles. In this paper, the basic composition of the changeable tracks was introduced and then a virtual prototype of the shovel loader with four tracks was established according to the truth designing dimensions. After which the simulation was done to analysis it’s steering qualities. The results indicate that the shovel loader with four tracks have strong maneuverability and stability when turning around. This simulation provides theory supports for the further research of this new kind of tread structure.

The Cu/Zn-14.1Al-0.9Si/Al joints were joined by flame brazing and furnace brazing, respectively. The influence of brazing methods on the interface structure and property of Cu/Al brazed joint was investigated. It was found that the interface structure near Cu substrate of the joint with different brazing method are both Cu/diffusion layer/Al4.2Cu3.2Zn0.7 layer, but the thickness of the interface layer of the joint with the flame brazing (3-4μm) is obviously thinner than that of the joint with the furnace brazing (5-10μm). The filler metal zone of the joint with flame can not find the Cu-Al IMCs. Instead, the block CuAl2 IMC can generate in the filler metal zone of the joint with the furnace brazing. For thinner interface layer, the joint with flame brazing has higher shear strength of average 60.5MPa, which is 20.6MPa higher than that of the joint with air cooling (39.9MPa).

There is different applicable transmission capacity and range between 1000kV and 500kV AC transmission. The traditional method is to use the continuous power flow algorithm by BPA simulation software. But this method is complicated and time-consuming. Calculation is particularly large when electricity has a variety of power demand analysis. This paper presents an algorithm based on the AC line transmission capacity, using MATLAB software programming to achieve the establishment of UHV AC transmission model and economical optimization strategy. The method can use thermal limit, voltage limit, landing stability constraints to get the AC line transmission capacity curve by considering the factor of power network strength. On the basis of this method, an UHV AC transmission model can be built combining with unit capacity annual cost algorithm, which can meet the power transmission of arbitrary transmission capacity and the optimal economic of any transmission distance, has an important reference significance and practical value for the planning and construction of electric transmission lines in China.

Based on the difficulty to accurately control temperature for torch brazing, the study is concerned with developing low-melting-point solders for brazing pure aluminum. For this purpose, Ge and Zn have been chosen to be added to Al-Si-based alloy. The melting characteristic, wetting property of solders with Al and mechanical property of the brazed joints were investigated. The results show that the addition of 10 wt. % germanium into the traditional Al-12Si (wt. %) filler metal causes its liquidus temperature to decrease by about 23 °C. An addition of 30 % zinc into such Al-Si-Ge ternary alloy will cause its liquidus temperature to drop further to 525 °C. The solders have good wettability with Al. With the increase of Zn content in the alloys, the spreading areas of solders exhibit nonlinear decrease, and there exist a very large value at the zinc content of 15%. When Al-Si-10Ge-30Zn solder was used to braze the pure aluminum, an optimized bonding strength of 116 MPa was achieved.

The initial designed structure of the diameter measuring gauge of filter rod forming machine is too large, so that it cannot be installed in the limited space of filter rod forming machine. Because of this, the structure of the diameter measuring gauge is redesigned in order to overcome the space constraints of filter rod forming machine. Firstly, the diameter measuring gauge of KDF2、KDF3 type filter rod forming machine is redesigned by combining the advantages of the theory of inventive problem solving (TRIZ) and constraints (TOC). Next, through constraints theory, finding the main contradictions of initial design and then contradictions can be eliminated by using inventive problem solving theory. Finally, diameter measuring gauge of filter rod forming machine design should be available, and the product design successfully. It is the first time that this type diameter measuring gauge is designed and installed on the KDF2、KDF3 type filter rod forming machine successfully across the country.

This study researched the aerodynamic characteristics of a two-dimensional trajectory correction fuze used for the common artillery ammunition, which increases the targeting accuracy by decreasing the circular error probability. The correction fuze has a pair of fixed canard and a pair of steering canards for roll control and guidance. In this study, computational fluid dynamic (CFD) simulation is performed to study the aerodynamic characteristics of the trajectory correction fuze. The primary purpose of this performance was to predict the aerodynamic coefficients and flow field over a spin-stabilized projectile with the correction fuze. Calculation covered from-10 degrees to 10 degrees steering canards deflection over speed range from Mach 0.6 to 3. The results showed the variation law in the rotary moment of correction module and the control forces of the steering canards with the Mach varying, providing aerodynamic reference for the research of trajectory correction projectiles in the future.

Heavy metals (Hg, As, Pb, Cd, Cr, Cu) pollution in soil samples of Rosa sterilis planting areas located in Wudang District in Guiyang and Pingba County in Anshun was studied using a new evaluation theory of pollution loss rate, and following a series of methods for Rosa sterilis leaf including over standard rate, enrichment coefficient, single pollution index and comprehensive pollution index, the heavy metals pollution of the two Rosa sterilis planting areas was analyzed and evaluated. The results showed that the soil comprehensive pollution loss rate ranged from 12.73% to 28.26% in Wudang District samples, most of which belong to light pollution level. The comprehensive soil pollution loss rate of the sampling points in Pingba County varied from 9.68% to 16.10%, which belong to fairly clean level. Meanwhile, the experimental results for the Rosa sterilis leaf showed that the contents of Cr and Pb in both planting areas exceeded the permissible limit, while other elements were below the safe limit. The six heavy metal elements in Rosa sterilis leaf did not accumulate.

In classic radial sampling scheme, angle intervals between adjacent straight sampling lines are the same. And so the coherence between the sampling matrix and the sparse matrix is high. Many pseudo-shadows will occur on the reconstructed image. For this problem, we put forward a novel sampling scheme in which the scan lines are placed in the manner of golden section angle interval. In the resulting sampling matrix, the scan lines scatter randomly on the whole. Experimental results demonstrate that the algorithm proposed in this paper has lower correlation coefficient between sampling matrix and sparse matrix than classic radial sampling scheme and random radial sampling scheme. Image can be accurately reconstructed by collecting less data than the other two schemes.

For vehicle-borne LiDAR, a mathematical model is built for the computation and reconstruction of laser point cloud with the scanning data, GPS data and IMU data. 3D point cloud of the road and the scenery on the both sides of the road is obtained. Then according to the trajectory of the vehicle, 3D roaming for the scenery on the both sides of the road is realized using OpenGL 3D engine technology. This technology provides a probably feasible way for anti-collision of vehicles and aircrafts when driven at night, in the heavy fog or flying between the mountains.

Biologists agree that real-time methodologies are an interesting new topic in the field of electrical engineering, and cryptographers concur. In this paper, we argue the emulation of voice-over-IP, which embodies the typical principles of crypto analysis. We motivate new homogeneous symmetries, which we call Niceness.

The implications of empathic models have been far-reaching and pervasive. Here, we verify the deployment of systems. In this position paper, we verify not only that context-free grammar and fiber-optic cables can agree to achieve this mission, but that the same is true for fiber-optic cables. This follows from the development of architecture.

In this paper, frame differential method will be used to detect moving targets in a static background video file, and pre-contour can be obtained by binarizing the detected targets . However,, the result are not what was expected, so the expansion and corrosion of mathematical morphology are used to extract the final contour of moving targets. in the progress of dealing with massive data , mathematical morphology is not good enough to achieve the need of the real-time in video surveillance. Considering the dilation and erosion is a kind of parallel processing operations, in order to improve the speed of mathematical morphology operations, this paper offers detailed implementation process of the dilation algorithm for parallel computing on GPU. Experimental results showed that GPU parallel processing on mathematical morphology algorithm faster than the CPU serial processing.

In order to have a good understanding of the geotechnical behavior around underground opening excavated in stratified rock mass, numerical simulation of a gate-shaped cavern excavation was conducted by applying a transversely isotropic model base on microstructure tensor method. The simulations were performed under the assumption that both the beddings and the in-situ middle stress vector run parallel with the cavern. Effect of the dip angle of beddings and that of in-situ major stress vector on deformation and failure of rock mass around the cavern was investigated. The mechanism underneath the image of deformation and failure was also discussed. It is found that the dip angle of beddings has less influence than the in-situ stress on deformation while the dip angle of bedding and the direction of in-situ major stress vector are equally important to the failure of surrounding rock mass.

This research was carried out according to the actual needs of plateau kitchen vehicle. However, these military equipments have played important roles in the military exercises, earthquake relief, and other major activities, they does need urgent improvements in the using process. Among those problems to be solved, drift distortion of pressure cooker signal transmission on account of low temperature of high altitude, inability of achieving accurate control, and untimely feedback of service demand included. The pressure automatic control system of plateau kitchen vehicle which is based on Single Carrier Ultra Wide Band (UWB) wireless technology (SC-UWB), will completely solve the above problems, and the followings are innovations of this study: Firstly, Single-carrier ultra-wideband wireless transmission technology was used in this study, which was in accordance with Chinese Standard and based on chips produced by China. This would satisfy the needs of real-time transmission in pressure and temperature information under extreme environment, and solve technical problems such as signal integrity and communicational confidentiality, and this would also eliminate technical problems such as signal distortion, hysteresis, drift, high deviation repeatability of automatic control system of plateau kitchen vehicle in extreme environment. Secondly, intelligent sensor systems were connected to the Internet of things (IOT). To develop Industrial Personal Computer (IPC) according to the management system and daily use of this equipment and to lead the equipment to have node function of access to the Internet of things, would be the foundation of all kinds of beneficial exploration in the management of Internet of things, and also the guarantee of technology standard of Internet of things in military equipment of future. Then, the existing equipment can smoothly be switched in to avoid duplication of investment.

A robotic arm control system based on LabVIEW and FPGA is presented in this paper. It is built with USB camera, PC, FPGA development board and 4-DOF robotic arm. In a way with high performance-price ratio and strong expandability, the system achieves a series of functions: capturing and processing images, identifying the target, planning the path, driving the actuators, and finally, grasping the target. Users can not only monitor the situation of the workbench, but also real-timely grasp the object in the area.

This document proposes a novel two-transistor forward DC/DC converter with resonance reset. It is recommended because the duty circle is able to exceed 50% and the efficiency of the converter is higher which is superior to the conventional. The principle of operation of the enhanced configuration is illustrated and some simulation is employed to prove its practicability and superiority. Finally a 80V~140V input, 12V/8.3A output DC/DC converter prototype is founded for verification.

The paper innovatively proposes using atomic force microscopy (AFM) and the concept of specific down force energy (SDFE) to establish a method for fabricating T shape nanochannel grooves on silicon (Si) substrate. Using the single-pass multi-layer cutting method of nanochannel groove using AFM proposed by the paper, a nanochannel looked like T shape is fabricated. For fabricating T shape nanochannel, it is set that cutting is firstly carried out for one pass on each cutting layer at a fixed down force. Then the probe carries out cutting for repeated passes. Using this cutting way by AFM and SDFE theory, the cutting depth and width of each pass can be predicted. The results of simulation and experiment of fabricating method for T shape nanochannel is further compared.

The Internet of Things (IOT) provides people with a more integrated and intelligent services. The applications based IOT is focus on the solution driving safety in the paper. The design of driving safety control system based on the IOT is proposed and the topology of the system is given. Meanwhile, the alcohol content testing modeling of human blood after drinking is established using the simple differential equations sets. Meanwhile, the model is established and the model solution is given. In the end, MATLAB fitting curves of alcohol content in the blood is proposed and the simulation results showed whether measures are taken after driving, such driving permitted. it shows deeply intelligent driving safety control system can provide mankind with the better services of personal security.

Based on the integration of the genetic algorithm and particle swarm algorithm, a network congestion control method is proposed for path optimization, which takes the load balanced distribution function and the resource consumption function as optimization target and optimizes path under the condition of meeting a number of QoS metrics such as bandwidth, delay, expense. Aiming at avoidance of network congestion, the approach attempt to minimize the network resource consumption and balance the distribution of network load. Simulation results show that the method is effective and reliable.

A nonlinear dynamic compensation for probability analysis in fault diagnosis of electric equipment was reported. Because of the limitations of Threshold temperature diagnosis method and the traditional Bayesian theory fault diagnosis method of electric equipment, a nonlinear SGompertz model and quadratic power model were used to compensate the diagnosis results for the influence of equipment aging and running temperature, then the maximum probability principle was adapted to judge whether the equipment is in malfunctioning state. The 3-D simulation results indicates that: (1) there is a strong relationship between the status and equipment aging and running temperature; (2) an obviously difference exists between linear and nonlinear compensational results of the characteristic temperature region. This proposed methodology is testified having important significance in improving the reliability and the information level of power transformers operation.

Radiation characteristics and mutual coupling are the important factors to the integration design and arrangement for airborne antennas. And the study of them is significant to the EMC of airborne electronic systems. Therefore, by using UTD, a study of predicting the far field pattern of a monopole mounted on the fuselage of an aircraft is described, and the method of computing isolation between airborne antennas is referred to. Initially simple model of large airplane is given by the principle that configuration should be simplified while electromagnetic radiation characteristics should not be neglected. Furthermore, single order, two orders as well as higher orders ray tracing are discussed based on the basic modals such as cylinder, taper and flat. The analytical solution of ray tracing is given out when it exists. If the analytical solution of ray tracing doesnt exist, faster numerical searching method is recommended. Then shadow judgment is introduced briefly. Lastly programs are made, and the results are proved true by comparing them with relative referencesv [1].

One of the main failure mechanisms in semiconductor device is the thermal breakdown of compact multi-chip (CMC) module. In order to avoid the compact layout or location of the heating chips, the distribution of the chips on printed circuit board (PCB) should be optimized to decrease the thermal breakdown probability of device. Based on the finite element theory, we simulated the three-dimensional space thermal field distribution of two kinds of PCB that the same chips were layout in difference ways in this paper. By analyzing the simulation results, we can find that the maximum temperature of the optimized CMC layout will be decreased about one degree. The simulation method and the conclusion of this paper will have significance effect for CMC design and optimization.

The choice of wind measured data and numerical simulation method has an important impact on the results of wind resource assessment. This paper will take a wind farm, in Yangjiang City, Guangdong Province, for an example and discuss the simulation accuracy by linear model WAsP and nonlinear model based on simulation software Fluent. First of all, contrast mean absolute percentage error (MAPE) about simulated wind speed under four kinds of wind conditions, which are simulated by four sets of wind data in WAsP, and then select the wind data with the smallest . Then, using WAsP and CFD method simulates wind field by the optimal wind data. Compare simulated wind speed and annual generation capacity. In this paper, the simulated wind speed in the simulation model CFD based on Fluent is closer to the measured wind speed. The MAPE of wind speed and annual generation capacity by CFD model is smaller than that by WAsP. Therefore, for the wind resource assessment in the complex terrain, the nonlinear model CFD based on Fluent will be qualified to response the relationship between wind resource and terrain, simulation accuracy, and has higher simulation accuracy than the linear model WAsP.

Architectural space evolution process and form of railway passenger station are studied in this paper. Firstly, architectural connotation evolution of railway passenger station is distinguished into three phases, namely railway-oriented passenger station, comprehensive transportation hub and urban complex. Then, architectural space evolution of three basic functional divisions, namely yard, station building and square, are studied. Furthermore, architecture space evolution of overall railway passenger station is divided into five stages with respective features of yard-dominated, yard-building-square plane layout, yard-building-square three-dimension layout, comprehensive transportation hub, and station complex. Finally, railway passenger station architectural space evolution in China is analyzed.

The paper adopts large deformation elastic buckling finite element method, researches the out-of-plane stability of lateral braced web openings circular steel arches under the distributed radial load and considers the effects of rise-span ratio, arch foot condition, brace rigidity and brace quantity. Research results demonstrate that the out-of-plane buckling load of web openings circular arches increases with the rise of rise-span ratio and increases with the improvement of arch foot constraint. Buckling half waves increase gradually with the increase of lateral brace stiffness. When brace stiffness reaches the brace critical stiffness, the out-of-plane buckling load of steel arches increases will no longer increase with the rise of the brace stiffness, and the buckling mode of steel arches will transit from out-of-plane instability to in-plane instability. The improvement degree of lateral brace to the bucking load of web openings circular steel arches depends on the lateral brace quantity and the size of the brace intervals.

this article do research in explosive broken problem, using the triple differential of the explosive roll type crushing technology to realize safe automation, take man-machine isolation operation measures, effectively reduce the labor intensity of workers, improve working environment ，ensure the personal safety and broken after medicine block size and crushing efficiency, it have high safety and reliability, certain promotion value, laid a solid foundation of technical innovation for the military and civil industry.

Electroencephalogram (EEG) is generally used in Brain-Computer Interface (BCI) applications to measure the brain signals. However, the multichannel EEG signals characterized by unrelated and redundant features will deteriorate the classification accuracy. This paper presents a method based on common spatial pattern (CSP) for feature extraction and support vector machine with genetic algorithm (SVM-GA) as a classifier, the GA is used to optimize the kernel parameters setting. The proposed algorithm is performed on data set Iva of BCI Competition III. Results show that the proposed method outperforms the conventional linear discriminant analysis (LDA) in average classification performance.

This paper aims to explore the dynamic behavior of the twin-lift lattice crane truss. The designs used ANSYS for finite element analysis. The situations of vibration and the resonance behavior of localization were dynamically analyzed. The results of this research could provide the engineers with useful information in understanding the dynamic vibration behavior of the crane system.

As a social network, microblog has obtained great attention and gotten wide application. Applications of microblog need to retrieve quickly information with the support of real-time search technology in order to implement information sharing. A query classification algorithm of microblog for real-time search was put forward. Based on question classification mechanism, the algorithm divides queries into two categories: the candidate queries and the popular queries, and takes separate storage strategy. Test results show that the classification algorithm can reduce real-time search time and improve the efficiency of retrieval.

The characteristics of PID controller, Active Disturbance Rejection Controller (ADRC) and Linear Active Disturbance Rejection Controller (LADRC) are introduced in the paper, then the parts which can be improved are analyzed, which leads to the topic of balancing linear and nonlinear elements in controller. LADRC with FFTD is used as an example in simulation experiment operated in Matlab7.0.The results shows that the control effect of LADRC with FFTD is better than other three controllers above. The simulation results and perspectives in paper offers reference for combining linear and nonlinear controller and balancing difficulty and performance.

In this paper, an ABC (Always Best Connected) supported QoS (Quality of Service) unicast routing scheme is proposed. In the proposed scheme, in order to overcome difficulties on accurately measuring network link parameter values and exactly expressing user QoS requirements, the knowledge of the fuzzy mathematics and probability theory is introduced, and the range is used to describe these parameters; both of the users utility and the network providers utility are computed, and gaming analysis is taken to deal with profits of both the user and the network provider; EDPGA (Elitist Distance-based Pareto Genetic Algorithm) is used to find the specific QoS unicast path with Pareto optimum under Nash Equilibrium among all parties utilities achieved or approached. While comparing with unicast routing scheme based on Dijkstra and the game theory based fuzzy unicast QoS routing scheme, simulation results show that this proposed scheme is both feasible and effective.

As a new media platform, the social network like microblog has aroused wide concern in recent years. People become more and more interested in information from microblog. How to retrieval the huge amount of newly created contents in real time is the key issue of microblog, so real-time search is a scalable indexing service that microblog must provide. Analysis on Sina microbolg, a microblog classification and indexing process has been put forward on basis of partial indexing mechanism. Instead of indexing the whole dataset, a partial index is to index the records that may be queried with high probability. The classification scheme can effectively save the real-time search costs and obtain microblog data with high quality.

Stacked Alamouti coding in MIMO wireless communication systems was analyzed through equivalent channel.We derive an upper bound on the portion of the ergodic capacity that the stacked Alamouti scheme can achieve, which is dependent on the ratio of number of transmit antennas to that of receive antennas in the high signal-to-noise ratio regime. As a conclusion, it is shown that the stacked Alamouti scheme can approach the channel capacity as long as the number of transmit antennas is no less than two times that of receive antennas.

Source camera detecting, which is about establishing whether or not the images of interest are taken by the same camera, is a challenging problem. Most CFA(color filter array) interpolation algorithm characterize the feature of camera which take the image. In this paper, we propose an improved algorithm. Instead of using inter-channel demosaicking/color interpolation traces, we first extract four in-and-inter-channel variance maps, respectively, and then extract the shape, similarity and difference features of maps for camera model identification. The experimental results show that the method had significantly improved the accuracy rate of source digital image identification.

In this paper, we propose a new discrimination method using image statistical characteristics is proposed which is designed to distinguish natural images from photorealistic computer graphics. Using Benford model as statistical basis, we conclude statistical properties of the MSD (most significant digit) of AC (Alternating Current) coefficients in DCT (Discrete Cosine Transform) domain of natural images and computer graphics, and then we constructed the detection model of the proposed algorithm. Experimental results show that this method can identify natural images and computer graphics effectively, compared with the existing algorithms this method has a higher recognition rate, which comes to 95.22%.

This paper introduces a new method about the downlink power allocation in LTE system, first, eNB indicates the downlink power allocation information through MAC Control Element, second, UserEquipment calculates Energy Per Resource Element of Physical Downlink Shared CHannel Resource Element according to the downlink power allocation information, finally, UserEquipment use the new Energy Per Resource Element to decode. The advantage of the method is that processing delay is less, and it improves performance of downlink transmission system.

Difficulties of tunnel construction mainly appear in the entrance and exit stage, some adverse geological problems may occur. In terms of the tunnel at the Changsha-Kunming section of the Shanghai-Kunming passenger line, firstly, adverse geological phenomena at tunnel exits was described. Secondly, major factors leading to disasters were listed, including geology, hydrology and construction procedure. Combined with in-situ conditions, Finite Element Method (FEM) was used to analyze the instability mechanism of surrounding rock after the upper arch gate was excavated by three-bench seven-step exaction method. At last, through comparison between computed result and measuring data, several basic conclusions was obtained. It can make much sense to similar engineering.

DEM matching algorithm without control points is the base for detecting deformation method, the deformation existing in DEMs is treated as gross error. The detectability and locatability of multiple gross errors is very critical according to the surveying error and reliability theory. The interactive observations number (ION) derived from gross error judgement matrix is adapted in this paper. The relationship between zero-column vectors in judge matrix and the rank of the coefficient matrix of DEM matching is discussed in theory, and prove none zero-column vectors exist with real date sets. ION Equal to the number of redundant observations. Experimental results show that DEM matching algorithm has the detectability and locatability of multiple gross errors, and the deformation can be correctly detected by robust estimators in prearranged confidence level.

Progress as well as integration of wireless communication technology, computer technology and semiconductor technology, can integrate information such as the perception,acquisition and data processing in a very limited volume [. With the rapid development of wireless technology,wireless sensor networks greatly extends the applications of sensor network and Internet of Things as well as the new challenges to wireless communication technology. We will use STC12LE4052AD microcontroller and ultra-low power radio frequency chip nRF24AP2 embedded ANT protocol stack to complete the development of wireless sensor nodes in this paper.

Polyaniline (PANI) and polypyrrole (PPy) is developed rapidly with special physical and chemical performance. According to high catalytic activity, polyaniline is applied in a wide range of electrocatalysis area, especially for oxygen reduction. In this paper, electrochemical prepared polyaniline was used as catalyst as well as the loading of noble metal catalyst for manufacturing oxygen reduction electrode. Then the influence of carrier, noble metal and their binding forms to the ability of oxygen reduction were investigated by cyclic voltammeter. The result shows that PANI carrier was the most influential factor for oxygen reduction; for single noble metal catalyst, Pt shows bigger catalytic activity than Ag. And the best catalytic activity was optimized at dual deposited catalyst as Ag, Pt mass ratio to 23:100. Further more; compared to glassy carbon, graphite is much better for electrode basement.

In order to optimize the processing parameters of TiC/steel composite materials, in-situ TiC particle reinforced steel-based surface composites were prepared by vacuum evaporative pattern casting (V-EPC) infiltration process, and the structure and interface of the composites were investigated. The results show that, TiC particle size with Ti-C-20wt%Fe reaction system was much smaller than the composite with Ti-C reaction system in the same location of the composites. In the composites, the TiC particle size and volume fraction increased and spherical degree dropped from the tradition layers (interface between the substrate and the composite layer) to the outer surface. But the increase of TiC particle size (1-3μm) and volume fractions (25.8%-43.5%) in the composite with Ti-C-20wt%Fe reaction system was obviously lower than that of TiC particle size (1-10μm) and volume fractions (12.3%- 67.7%) in the composite with Ti-C reaction system. The bond zone between TiC particles and the matrices was totally metallurgical bonding without apparent interface. Comparing with the composite with Ti-C-xFe reaction system, the tradition layer with Ti-C reaction system has a poorer internal quality. The forming process of TiC in situ synthesized reinforced steel substrate surface composites prepared by V-EPC infiltrating process was infiltrating of the melting and carbothermal reactions of C and Ti powder the result of joint action.

The supervision system of hazardous chemical based on the WEBGIS technology is constructed, which displays the reality of the situation and simulates the accident consequence of security risks ( including major risk sources ) to the user in the form of map, realizes the registration of hazardous chemicals, enterprise qualification examination, administrative licensing of hazardous chemical construction projects, and investigation and rectification of the potential safety hazard in hazardous chemicals enterprise as well as management and supervision in other related business process through information means, and improves the ability of supervision and emergency rescue in chemical safety production. It has an important significance to prevent and control the major hazard. This paper introduces the supervision system of hazardous chemicals and the structure, database design, and system application of the supervision system.

This paper aims to design an ultrasonic cleaning machine for crops to provide the engineers with very useful information. First, the new practical model is designed, including the body shell, cleaning tank, ultrasonic generator and control system. Second, three vegetables (lettuce, cabbage and potato) are used in the experiment. The result shows the damage percentage after washed was 0%. The root vegetables are cleaned faster in this machine.

Have a large population because of being engaged in tennis, impact in ball and bat in the energy transfer produced, only some energy is changed into the kinetic energy that the ball rebounded, other energy will be consumed in the vibration of the ball, network thread and frame, among them the arm that the vibration of the frame certainly will be held bat by the human body is absorbed, load to cause arm produce tired to injure, certainly will absorb through bat transmission of bar by human body even, excessive load, cause arm weariness and strain, it is thereupon production to injure, probing into the vibration quality of bat becomes the very urgent theme, so this text aims at studying and striking the regional impact on vibration characteristic of tennis racket differently. Research this through experiment analytic approach, by accelerate rule amount of instrument and equipment waited for examine different to bump into area hold bat, take things vibration energy parameter on bat. This research obtains the important conclusion as follows: 1. In the impacting experiment of tennis racket, include driving board mode and node bending mode. 2. The natural frequency between 117Hz and 127Hz, amplitude and bending type that produce its have extensive, influence to arm. 3. The impacting area on the throat area, the vibration energy that the arm bears is biggest, secondly for the side area next for the tip area, it is the sweet district is minimum, so try not to deviate from the sweet districts in the batting area.

For the short life of hot work die in enterprise directly caused problems the waste of resources and the rising cost of production. Based on studying the biological prototype of crack-resistance of plant lamina and found that surface thermal fatigue crack is one of the main factors affecting the service life of hot work mould, it is put forward thoughts about the local bionic laser melting on mould surface to block cracks. Different from the traditional mould surface integral laser transformation hardening (LTH) technology, using laser melting simulating plant lamina to block cracks on the partial surface of mold, life of bionic strengthened die is improved within 1~1.5 times. Experiment results show that a new method is provided to improve the service life of casting mould and promoting this technology will bring significant economic benefits for the mould industry.