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A miniaturized circularly polarized (CP) antenna for ultra-high frequency (UHF) radio-frequency identification (RFID) reader is designed in the present paper. For the aim of miniaturizing antenna, the square radiating patch is opened by four T-shape slots. This can extend the route of surface current, as a result the operating frequency drops and the size reduces. In additional two diagonal corners of the radiation patch are truncated by a square to achieve CP operation. The designed antenna is calculated and optimized by HFSS. The optimized antenna exhibits satisfied performances, and is therefore suitable for UHF RFID reader applications. The designed antenna shows the advantages of small size, simple structure, and low cost.

Accurate measurement and modeling of complex surface is the foundation to precisely evaluate the error of complex surface. According to the NURBS method for rebuilding complex surface, a sampling data automatic replenishment method based on neural network is proposed and the sampling data with high precision is acquired. By using bicubic NURBS surface fitting method, the complex surface is rebuilt precisely and efficiently.

In order to determine the routing scheme of a line in city track traffic, a nonlinear constrained multi-objective 0-1 programming model is established, with the intervals as variables, and the optimal matching between the spatial characteristics of passenger demand and routing, as well as the minimization of operation cost as the objective functions. The equality constraint is built based on fuzzy clustering method, the number of variables is reduced, and the weighted coefficients are computed with objective function values. Taking Chongqing Rail Transit Line 1 as an example, a selectable routing scheme is calculated.

Mechanical properties of reactive powder concrete (RPC) containing fly ash were investigated under different curing regimes (standard and steam curing) in this study. The experimental results indicate that, flexural strength of RPC increased considerably after steam curing, compared to the standard curing. Steam curing had no significant effect on compressive strength of RPC. Increasing the fly ash content improved the flexural strength of RPC under all curing regimes considerably. The compressive strength reached a maximum (103.8MPa) when the fly to ash and cement ratio is 0.3.

To explore the influence of axial compressive ratio on seismic behavior of reactive powder concrete(RPC) beam-column joints,this paper carry out RPC beam-column joints nonlinear finite element analysis,using software ABAQUS.The effect of different axial compression ratio on the ductility,energy dissipation capacity and bearing capacity are studied,based on hysteretic curves and skeleton curves of the components.The results show that,with the increase of axial compression ratio,skeleton curves of the components tend to be steep when the vertical load of beam ends exceed the peak point.The ultimate bearing capacity of the components are improved with the increasing of axial compression ratio which is less then 0.6,while the ultimate bearing capacity show a opposite trend when the axial compressive ratio exceed 0.6.

An automatic injection mould machine for servo electric control system was introduced to deal with the existing problem of the control system of hydraulic injection mould machine. With the industrial control computer, the embedded industrial control computer is used as Main Processing Unit, other four units which are ejection, measurement, mode-locked and ejector were controlled by servo motor computer, with the combination of the control structure of cascade system. With the transformation instruction of AC servo, the control was accurate, the quality of products were improved, the energy was saved and consumption was slowed down..

The paper discusses the collaborative optimization problems with bounded. Based the penalty function the system-level optimization convert to a unconstraint programming. To the discipline-level optimization, the normalized weighted coefficients are used and combine relaxation factors to solve. It uses the relaxation factor to expand the feasible region, and possibly makes the iteration in the calculation process run inside feasible region. The data have shown that the algorithm has expanded the choice range of the initial points with high calculation accuracy and better algorithm stability.

In this paper, one ground freezing monitoring system based on Zigbee is designed. System is divided into four parts: sensor cable based on 1-wire technology, monitoring terminal with a drive circuit based on Zigbee, Zigbee coordinator and monitoring host with the function of network. This paper mainly introduces the network communication system. The system is suitable for the construction site of the engineering test; anti-interference and robustness of system are strong. It implements the project managers and experts operation of real-time control without time and space limits for freezing monitoring system. It provides technical support for the application of freezing engineering.

Given the path situation of Xiyue substation 220kV four outlets project crossing Shunde waterway section,this article applies of Dao Heng tower full stress analysis software and the finite element analysis software ANSYS to two steel pipe combination of angle steel towers to carry on design research,contrast axial stress of two kinds of software,analyse the reasons of axial stress difference.

Choosing LW15-550Y porcelain high voltage SF6 circuit breaker as the research subject, we designed the lead laminated rubber bearing (LRB) seismic isolation device for LW15-550Y circuit breaker. We finally gets the results that the LRB isolation system increases the flexibility of the breaker structure and improves the seismic performance of the high voltage circuit breaker structure.

According to the high real-time and the high anti-interference which required by the machanical arms of humanoid robot, a distributed controllers for mechanical arms of humanoid robot system based on CAN is developed, to which C8051F041 micro controller is applied as the joint controllers. The circuits of incremental discs and speed detection as well as their applications are designed. The achievement of develop and design on distributed controllers for six degrees of freedom mechanical arms fulfills the trajectory requirement of humanoid robot qualification and the system according to the study design.

The characterization and use in sludge dewatering of a novel bioflocculant M-C11 produced by Klebsiella pneumoniae was investigated. The purified M-C11 was composed of 91.20% sugar, 4.61% protein and 3.91% nucleic acids (w/w). Fourier transform infrared (FT-IR) spectroscopy of purified M-C11 confirmed the presence of carboxyl, hydroxyl, methoxyl and amino groups. The sludge resistance to filtration (SRF) decreased remarkably from 11.64×1012 m/kg to 4.66×1012 m/kg under the optimum conditions (pH=6, 3 mL bioflocculant and 4 mL CaCl2 dosage), after being conditioned with bioflocculant M-C11, which was more efficient than inorganic flocculants. Results showed that M-C11 could serve as a substitute for chemical conditioners and a promising alternative to the sludge treatment industries.

A folded dual-band monopole antenna for 2.45 GHz and 5.8 GHz RFID tag applications is proposed in the present paper. It is formed by two folded monopole antennas for reducing the geometric size of the tag. One of them operates at 2.45 GHz, and the other operates at 5.8 GHz. The input impedance of the proposed antenna is designed to be conjugate matched to the chip impedance for the maximum power transfer. This antenna is modeled, analyzed, and optimized by HFSS. The simulation results demonstrate that the performances of the proposed antenna can satisfy the requirements of RFID system. The characteristics of the proposed antenna are simple structure, low cost, and small sizes.

With the rapid development of RFID (radio frequency identification) application, the design requirements of RFID tag antenna are also increasing. A design of dual-frequency or multi-frequency tag antenna has become fashionable. In the present paper, we design a dual-band RFID tag antenna, which consists of a bent microstrip patch and rectangular microstrip patch. The designed antenna is analyzed and optimized by HFSS13. Simulation results indicate that the tag antenna has the characteristics of double band, high gain, and good radiation pattern.

A printed inverted-F antenna for RFID tag at 5.8 GHz is designed in this paper. The antenna structure consists of an inverted-F patch, a substrate layer, and a ground plane. To reduce costs, the FR4 is selected as the material of substrate layer, which is used commonly in PCB (Printed Circuit Board). Its relative permittivity is 4.4 and a loss tangent is 0.02. The inverted-F patch and ground plane are laid on/under the substrate layer respectively. The designed antenna is modeled, simulated and optimized by using HFSS (high frequency electromagnetic simulation software). Simulation results demonstrate that the printed inverted-F antenna can satisfy the requirements of RFID Tag applications.

tower consisted of steel tubes and angel steels has equal advantages which steel tube tower has and not easy to happen some bar breeze vibration,but but the wind vibration response for such transmission tower structure research is less. In the engineering background of a tower consisted of steel tubes and angel steels , set up the finite element model for transmission towers. Using Kaimal spectrum for numerical simulation of wind velocity time history. Of 90 ° Angle of wind direction wind to dynamic response are analyzed, the results show that for the displacement, the maximum of dynamic analysis results 88% larger than the result of the average wind, 53.7% larger than standard wind load static result; For axial force, the maximum of dynamic analysis results 147% larger than average the result of the wind, 108% larger than standard wind load static result. So in view of the transmission tower structure dynamic response analysis should be more precise.

A speed controller with fuzzy sliding mode algorithm was designed by using power function instead of the traditional switch symbol function, and adjusting the approach law parameters combined with fuzzy algorithm in real time, as it was difficult to eliminate the chattering when designing a PMSM speed controller with the traditional sliding mode variable structure. The mathematical model of the PMSM was built in Matlab/Simulink with the vector control strategy. The simulation results showed that the control system of PMSM built by improved sliding mode had quick velocity response with less overshoot and significantly weakened chattering, which verified the efficiency of the improved algorithm in the simulation stage.

The content of selenium in Shiitake was determined by hydride-atomic fluorescence spectrometry and the sources of uncertainty were evaluated. Each parameter in mathematic model was analyzed to evaluate the type A and type B uncertainties in the method. To obtain the uncertainty evaluation , each uncertainty component was synthesized and extended by the current international method . The evaluation results showed that the major source of the uncertainty in the method was the sample solution volume and the standard curve.

The safety storage of rice or brown rice moisture content is below 14% ,hardness and brittleness is larger to low moisture content of brown rice, the crack in the manufacturing process of milling rice and broken rice rate is higher, milling processing energy consumption to increase, and the rice surface roughness is low .In this paper, using mathematical simulation method based on the theory of the humidifying, thin layer of humidifying dynamics model is established, and brown rice humidification conditioning properties are studied. Results show that the unit heat consumption is reduced with the increase of air temperature,humidifying rate increases, the bread machine temperature linearly increases; With the increase of wind speed, unit heat consumption increases, humidifying rate increased.

For the superheterodyne reconnaissance receiver detected "signalBatch-increasing" phenomenon, research on radar signal sand the intercepted characteristics of reconnaissance receiver from the frequency domain, pointed out that "Pulse-width split" and "Pulse-width truncated" caused by Emitter signal spectrum loss is the reason of "Batch-increasing",On this basis, analyzed the strategies of "Batch-increasing" signal processing .

Analyzing the current developing status and actual problems of radar system simulation, based on continuous system simulation, combining signal simulation and function simulation, considering current development of simulation technique and the request of air battle to EW, the simulation system of phased array radar based on MATLAB/SIMULINK is presented and designed, which conquered the contradiction between simulation precision and real-time characteristic. And the key techniques of composition, modeling and exploitation of modules are studied in-depth. The simulation system is checked and tested by illustration of one jamming to phased array radar system in the end. Simulation is carried out whose result verifies the efficiency. The successful exploitation of the system will supply the analyses evaluation of the whole simulation system efficiency with platform and basis, which has instructive sense for the tactical use and simulation of phased array radar.

To make clear what the impact of correlation between clustering factors to land use zoning is, taking Linxiang prefecture as the object of investigation, this study firstly establish a land use zoning index system, and then get two zoning results with hierarchical cluster analysis. One is achieved with correlation reserved; the other is approached with the correlation eliminated by principal component analysis. Analyze the two clustering results comparatively associated with the objective reality of land use, and we conclude that the correlation between indices has a positive effect on the zoning result and should be reserved.

This paper defined the hereditary property (or constant property) concerning graph operation, and discussed various forms of the hereditary property under the circumstance of Cartesian product graph operation. The main conclusions include: The non-planarity and Hamiltonicity of graph are hereditary concerning the Cartesian product, but planarity of graph is not, Euler characteristic and non-hamiltonicity of graph are not hereditary as well. Therefore, when we applied this principle into practice, we testified that Hamilton cycle does exist in hypercube.

Measurement results of spectral reflectance spatial distribution on multi-crystalline silicon solar cells surface are presented. The optical measurement apparatus employs a specific designed micro-spectral reflectance meter. It is suitable for working in visible wavelength range; measurable sample size can be as small as 0.06mm. Results of reflectance distribution on mc-Si solar cell are presented as a spatial sampling interval of 0.1 mm. The peak values of spectral reflectance appear about 400nm wavelength and vary from 10% to 30% with the spatial position on solar cell.

Landmark correspondence plays a decisive role in the landmark-based multi-modality image registration. We combine RPM (Robust Point Matching) and improved Mean Shift to estimate the correspondence of landmarks in images. We improve the target mode and bandwidth used in Mean Shift, and we also perform RPM to estimate the initial landmark correspondence. Next, we use improved Mean Shift to adjust corresponding relations between points. Our method is benefit to make corresponding relations between points more accurate and impels the convergence process of RPM to be related to the image content. Experimental results show that our method can achieve accurate registration of the multi-modal images.

In order to study and solve the problem of connection on the part of the prestressed tendons RPC concrete pole engineering. Design connecting flange suitable for the existing part of the prestressed tendons RPC concrete pole developed by our group used the connection flange in Steel tower as the prototype.Through the ABAQUS software to establish the finite element model between the connection flange and part of the prestressed tendons RPC concrete pole, and carry out finite element analysis.Through the finite element analysis to get results whether the design of connecting flange can meet the strength requirements when the prestressed tendons RPC concrete pole is under ultimate load, so to get the practical design method of the 500kv part prestressed RPC concrete pole connecting flange.

This paper describes the machining method of complex surface face gear used CNC machine tools and hob cutter, Based on surface characteristics and gear hob principle. A coordinate transformation process is explained in detail in the five axes CNC machining of complex parts. A CNC hob method is proposed about surface orthogonal gear. An experiment is done for validating the method.

The data of engine failures about tobacco Heights Department of tractor operating in field conditions was collected by running engine failure tracking tests. An evaluative model was established using the theory of Fuzzy Neural Network(FNN) for the tractor ' using reliability, based on the data of failures about tractors, the observed values of the reliability standards were made out and the degree of subordination was figured out, finally, the evaluative result for the tractors ' using reliability was obtained by evaluative model of reliability. The result of research can be used as references for the improvement of reliability and maintainability of tractor engines, and for the establishment of maintenance strategy, and it also lay a theoretical foundation for studying the improvement of evaluation method for the tobacco Heights Department of tractor ' reliability as well.

This paper had 3-dimensional models of a spiral bevel gear and a cutter in real size assembled in accordance with the milling process and transformed them into the finite element analysis (FEA) code. Then several researches on simulation methods of this milling system had been conducted, and stress distributions of gear surface after processing under different cutting conditions was given out, based on which a cause-effect study was carried out about the correlation between cutting parameters and the stress distribution, leading to methods of maintaining a low-stress condition during manufacturing.

The stroke and the material characteristics of the large five-axis machining center were expounded; a structure similar to the truss of the reinforced beam plates was designed according to the design requirements of the beam structure, this structure could make the frame gain high rigidity in small size, the frame made by the rods could be constituted with high rigidity, the overall rigidity of the machining center could be improved 23% - 25%; three different beam structures were designed, and the finite element analysis software ANSYS was carried out to analyze their static characteristics, the maximum deformations in three directions X, Y, Z were obtained; compared with other structures through the comparisons on mass, stiffness and performance, the optimal structure was obtained, its mass was 1818Kg, and its maximum deformations in X, Y, Z directions were 0.45mm, 0.07mm and 0.13mm, respectively.

In this paper, the repair capacity of SMA wire by using internal and external installation was studied. The SMA wires were embedded in epoxy resin and silicon cement mortar beams made of polymer clay, and then three-point bending test was conducted on the composite beam. The ability of beams which embedded SMA wires was also studied. On the other hand, the SMA wires were installed in the external of the epoxy polymer clay cement mortar, then three point bending test was also used and its self-repair ability was also studied. The results show that the crack can be repaired very well under these two methods. If there are cracks in existing buildings, we can use an external installation method to repair them. In order to ensure the new buildings crack free, both methods are feasible.

Constant stress tensile creep tests were conducted on an AZ 91–25 vol.% Al2O3-SiO2short fiber composite and on an unreinforced AZ 91 matrix alloy. The creep resistance of the reinforced material is shown to be considerably improved compared with the matrix alloy. The creep strengthening arises mainly from the effective load transfer between plastic flow in the matrix and the fibers. Microstructural investigations by SEM revealed good fiber–matrix interface bonding during creep exposure. Short fibers have a great function in load bearing and load transfer, and greatly hinder the dislocation movement, thus enhancing the creep resistance of the composite. Damage and multiple rupture of aluminum silicate short fiber, quality of the interface combination between aluminum silicate short fiber reinforcement and the matrix, are two important factors of the creep deformation microstructure process control of Al2O3-SiO2(sf)/AZ91 composite. The creep mechanism of the composite is dislocation and grain boundary sliding control.

The purpose of this study is to provide a correct and timely diagnosis mechanism of shearer failures by knowledge acquisition through a fuzzy inference system which could approximate expert experience. Concerning a question of uncertain knowledge expression and reasoning in shearer malfunction, the fuzzy inference theory is used in shearer malfunction fault diagnosis. The fuzzy relation matrix of faults and signs is deduced based on deep research of failure mechanism and expert experience, which agrees with fault and fault symptoms non one-to-one relationship and human thinking. Fault characteristic parameter is calculated to corresponding subordinate degree, then is operated with fuzzy relation matrix and get fault fuzzy vector. Finally, the shearer malfunction fault is diagnosed according to certain diagnosis principle. The example proves that the method has less calculation, explicit conclusion and other merits.

Expert system of full-mechanized face equipment fitting based on artificial neural network is researched and processing method is presented in this paper. On the basis of this, BP neural network models for the forecast of production capability of mining face and the parameters of equipment fitting of full-mechanized mining face are built up. Employing these models forecasts the output, work efficiency and main technical parameters of full-mechanized equipment of the test mining face in Ji'er Colliery.

The enterprise clusters are many enterprises in the same region, which are centralized to produce the same mass products. In the context of globalization, the enterprise clusters are becoming an important force of the leading world economy. Based on investigating and analyzing for the enterprise clusters in south China, the local area networks of the enterprise clusters can be built by using multi-level distributed computer system. The CAD and MIS systems are integrated into the local area networks of the enterprise clusters so that the flexible manufacturing systems can gain manufacturing data from the integrated systems. So, the integrated systems greatly improve the productivity of the enterprise clusters. The CAD and MIS system integration model of intelligentization has been dwelt on in this paper.

Based on the idea of integrated design, a drive-transmission integrated linear electromechanical actuator is developed. The actuator consists of a permanent magnet synchronous motor (PMSM), a ball-screw and shells. By using coaxial assemblage, the ball-screw is inserted into the hole of the hollow motor rotor and the nut of the ball-screw connects with the motor rotor. In order to restrict the ball-screw rotating relatively to the shell, splines machined respectively on ball-screw and the shell come into being a spline pair. A driver based on a DSP processor and IGBTs plus a position feedback resolver forms a precise servo system.

In this paper, the existing research and key technologies of 4-DOF parallel robot are reviewed, i.e., mechanism, kinematics, singularity, workspace, dexterity, dynamics and control. Most of them are focused on mechanism and kinematics. The study in dynamics and control is relatively rare and not mature in practice, especially in how to optimize the control strategies to improve its performance. Finally, the research trend and unsolved problem of 4-DOF parallel robot is described.

To explore the impact of abrasive granularity, feed pressure and cutting feed speed on NC ultrasonic machining efficiency, a three-factor four-level orthogonal test was carried out, and data were analyzed to establish a ternary nonlinear regression model of NC ultrasonic machining efficiency. Furthermore, significance of the regression model and impact of all independent variables on dependent variables were studied. The study showed that when significance level is α = 0.01, the combination of the three factors tested impacts significantly on machining efficiency indicators. However, among the three factors, the abrasive granularity has the highest impact and its impact on the machining efficiency is nonlinear.

The spiral bevel gears of attack helicopter transmission systems are taken as an object in this paper. The numerical analysis model for starved elastohydrodynamic lubrication (SEHL) of spiral bevel gears is established on the basis of the analysis of load tooth contacts analysis and SEHL in elliptical contacts. The SEHL characteristics of spiral bevel gears are also analyzed. The results are as follows: during the course of a gear-tooth meshing cycle of the spiral bevel gear, the extremum of minimal film thickness and maximal film pressure occurs near midpoint of the path of contact, and leans to dedendum. The minimal value of the minimal film thickness is 0.39 um, and the maximal value of the maximal film pressure is 0.69 GPa. The value of minimal film thickness gradually increases with the increasing of meshing point velocity. When the velocity of meshing point exceeds 110 m/s, the increase became tardiness. As the load of meshing point increases, the value of minimal film thickness gently diminishes.

A novel mixed metal molybdates, Zn2(MoO4)(SeO3) 1 has been synthesized by a simple hydrothermal process. Samples obtained are characterized using powder and single crystal X-ray diffraction (XRD), transmission electron microscopy (TEM). Furthermore, the photocatalytic performances of samples obtained are investigated for degradation of RhB under visible light irradiation. photocayalysis experimental result has illustrated that the compound exhibits good photocatalysis.