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In order to make the traffic flow smoothly through the intersection, to minimize the delay time, must ensure that the control decision of the traffic signal is real-time and accuracy. Aiming at the existing problems of the traditional timing control method, analysis of traffic signal control parameters, performance indicators, put forward the fuzzy inference is applied to the traffic signal control system, puts forward an intelligent traffic signal control system based on fuzzy control; the vehicle queue length, inlet flow rate, green extension as the control parameters and simulation the results show that the proposed control method can effectively improve the traffic congestion, improve the vehicle capacity.

According Robot roller hemming is known as an assembly method with high flexibility and automated rate for closures in automotive bodies. The hemming tool is manipulated by controlling the industrial robot to complete the formation of closures (i.e. doors, hoods, tailgates and trunklids). In this paper, we shall first briefly introduce the rope hemming process, detail on the impact of process parameters on the rope height, roll-in and roll-out with the FEA model to simulate the rope hemming process. Then the rope hemming defects are discussed in later sections. This paper studies the process parameters and the methods to improve the rope hemming quality and provides a good reference for the practical application.

Influence of different pre-hem paths on the flange geometry was studied first. Among these paths could be vertical, oblique, horizontal. The result of the simulation shows that the vertical pre-hem path leads to less creep. To avoid the hemming quality defects around the corner of the outer-sheet, influence of the structure of the pre-processing steel on the hemming force was studied. And finally the design scheme of the table-top hemming machine and the basic operating principle were presented.

The direction and positioning of the missile could be affected by the vertical deflection which is at the launch point, so the impact point errors will increase. Based on the launch coordination, the target point position deviation formula which is caused by vertical deflection is deduced in this paper. The correction precise of the vertical deflection is also a factor of the impact point error. The simulation based on the deviation formula is conducted to analyze the affection of the vertical deflection and the correction precise of the vertical deflection. And the results show that the vertical deflection can lead to 1km error for the long range missile. In addition, if the precision of vertical deflection were improved , the impact point errors will be reduced 85m.

Brick-concrete structures and common buildings are destroyed in strong earthquakes. Based on physical mechanics, a pattern contrast illustrates three special designs of building structure---removal of basal markets and underground garages, use of corrugated beams, adoption of trapezoid bars---that may effectively avoid damages and casualties.

Along with our country economy fast development, the building and renovation is becoming more and more widely, layer for steel structure system, relying on its obvious advantages, has gradually become one of hot topics in the study of engineering. Combining with engineering example, through the integrity research, bearing capacity calculation, field exploration, the analysis of the concrete strength testing, etc., has carried on the appraisal on the safety of building structure, and analyses the feasibility of after add layer. In layer for steel structure design, at the same time puts forward the design and construction of some key points, provide a reference for similar projects.

This paper firstly discusses the techniques to optimize power consumption of the embedded operating system, and then optimizes power consumption of embedded Linux by adding DVS (dynamic voltage scaling) module and modifies the scheduling function in the standard Linux kernel. Finally, take a comparison test on arm920 platform. The test results show that: the power optimized Linux can effectively reduce the power consumption of the whole embedded system.

Steel reinforced concrete composite structure which apply in the high-rise buildings, not only save steel, but also have excellent properties in fire prevention, anti-corrosion, and seismic performance, and improve the speed of construction, economic efficiency.This thesis based on the analyse of a steel reinforced concrete composite structure tower and the domestic and foreign experts study use Finite Element Analysis software SAP2000 analyze the dynamic Performance of the structure to draw the inherent vibration period and frequency of the structure. The structure is analyzed to obtain its deformation with different height of the structural elements under a small earthquake. Structure and component in elastic stage when suffur a small earthquake. Using the mode decomposition response spectrum method and method of linear time history analysis, the maximum horizontal displacements of the structural layer, the maximum inter-story displacement and the maximum inter-story displacement angle is obtained to see if the results within a predetermined range.

The purpose of this paper is to introduce the important steps of OLP (off-line programming) for robot roller hemming, including acquisition of virtual environment, trajectory generation and optimization and calibration. And an algorithm for calibration was also introduced which is of high accuracy with lower cost. The feasibility of OLP for robot roller hemming was validated by the final experiment.

This article researched the influence of TCP-RTP distance on the accuracy of product in robot roller hemming through orthogonal experiments used as guidance to optimize the parameter of TCP-RTP distance in practice. Results reveal that the influence of the TCP-RTP distance of each step on the accuracy of a product is different.

With high volume and flexible automated production line becoming the future trend of automobile welding line, the modular gripper, as the role of the robot tool, is finding increasing application. This article concluded the deformation formula by detecting bending and torsion deformation of aluminum profile in tests and also provided guidance and rationale for designers.

In this paper, an experimental mixing equipment has been developed for producing low density material with a high volume filling rate of phenolic hollow microsphere. The experiments with the equipment aim to explore the feasibility of this equipment for industrial production and to optimize the process. Experiments have been made to evaluate the influence of the filling ratio and the mixing rotor movement on the mixing effect. The results show that when the volume filling ratio of the material to the mixing barrel is about 40% the mixing effect is the best. But with mixing time increasing, the broken ratio of hollow microsphere will increase too. To solve this problem, some changes on the rotor movement have been made. The results show that the broken ratio increasing rate becomes lower and the density becomes more uniform. These indicate that the broken ratio can be well controlled by a suitable production process.

In this paper, employing the mixing theory of polymer and the numerical simulation of polymer processing, numerical simulation model for dispersive mixing of solid powders in polymer matrix is studied, and a multi factor accumulative size distribution function is established. Based on this, the dispersive mixing processes of black carbon/natural rubber are studied using three-dimension dynamic numerical simulation, and the influences of operating conditions on the dispersive mixing of black carbon are analyzed. The simulation results show that the final size of solid powder aggregates is depended on the rotational speed of rotors. When the maximum shear stress of polymer flow field is sufficient to overcome the cohesive force of solid powder aggregates, the size of aggregates distribution will be related with mixing time.

In this paper, the 3D flow field and dynamic mixing processing in the continuous mixer with new-type rotors have been studied using finite element software package Polyflow. The influences of continuous mixer process conditions on mixing properties were analyzed by numerical simulation. The results show that the dispersion property is mainly affected by the rotational speed of rotors and the viscosity of polymer. Better dispersion property can be gained as and the viscosity increase. However, the distribution property is mainly affected by feed rate, and the distribution efficiency will reduce if feed rate is too fast.

Absrtract. In this paper, the method of ultrasonic vibration in preparation of multi-walled carbon nanotubes(MWCNTs)/epoxy resin composites was studied. Suspension specimens of MWCNTs/epoxy resin solution prepared by different ultrasonic conditions were compared to find out the influences of operating conditions on dispersion properties. In this study, transmission electron microscopes(TEM) were used to characterize the morphology of the blends and suspension stability was used to evaluate the stability of blends. The results showed that ultrasonic power, ultrasonic time and material quantity have great effect on the dispersion of MWCNTs in epoxy resin solution. Increasing ultrasonic power and time can improve dispersion of MWCNTs, and decreasing material quantity within an appropriate range was helpful to disperse MWCNTs into epoxy resin solution. The results of suspension stability were very similar with TEM results, which demonstrate that suspension stability of MWCNTs/epoxy resin blending could be used as an assistant method to characterize the dispersion of MWCNTs in epoxy resin.

Rapid detecting structural damage by lamb wave is an emerging technology in the field of structural health monitoring, and damage signal decomposition of Lamb wave, with the intent of obtaining reflection signal from damage, is the key point of detecting damage by Lamb wave. Therefore, this paper proposes a new algorithm for damage signal decomposition--similarity-based algorithm. In order to obtain reflection signal form damage, it simulates the reflection signals from damage and boundary with the waveform after the input signal has propagated a distance, and then optimizes the various parameters of the synthetic signal, which consists of reflection signals from damage and boundary, by genetic algorithm based on similarity so that the similarity between the synthetic signal and the damage signal reaches the maximum. Finally, simulation results showed the feasibility and accuracy of the algorithm proposed in this paper.

Studing the identification methods of sedimentary microfacies by the implement of self-organizing neural network model. Picking up the geometrical characteristic parameters and image characteristic parameters of the logging curves. Establishing the relationship of sedimentary microfacies patterns and well logging curves shapes by characteristic parameters. Developing the Sedimentary microfacies patterns identification system and applying it to 1000 wells of the southern area of Daqing Changyuan, the recognition rate can reach 90%, it can prove the validity of the method.

The effects of aging treatment on the damping capacities of ZA84-xSb alloys were studied. The results show that in the aging treatment process, because of following mainly reasons: (1) the dissolution of the ternary phases, (2) the increase of grain interfaces, (3) the increases of dislocation density, and (4) the micro deformations of matrix interfaces and the second phases, the damping capacity of ZA84-xSb magnesium alloys did not be reduced. On the contrary, whether at the low temperatures or high temperatures, its damping capacity is higher than as-cast alloy, which is of great significance for the application of ZA84-xSb magnesium alloys.

The paper builds up the model for exergy analysis of vapor compression refrigeration. According to the exergy analysis, it appears exergy loss degree of the main units in the system, and points out the way of reducing exergy loss and the approach utilizing energy rationally, and proceeds with exergy loss compare with aiming at that if condenser in surplus heat recycling. Conclusion is that adopting surplus heat recycling can reduce exergy loss. Furthermore, it analyzes exergy loss to a actual refrigeration aiming at temperature regulation, and provides the theory reference for improvement and optimization of the system.

This paper introduces calibration technique for robot vision system, aiming to enhance the robot’s ability to adapt to various environments. In accordance with a calibration plate and car body, we figured out the relationship among the coordinates of car body, camera, and robot by image acquisition, processing, analysis, and calculation. An algorithm was developed to deduce the coordinate transformation between robot frame and calibration plate frame with 4 points. Its feasibility was validated by the experiment.

This paper discusses the principle and practice that the crank-rocker mechanism was utilized as up-down. MATLAB was used for analysis and optimization for the up-down mechanism, in order that the designed path can be realized on the coupler. And then ADAMS was used to create a virtual prototype model for the crank - rocker mechanism，to analyze the kinematic parameters, and to validate the feasibility. The paper tried to setup a universal method for electric shuttles mechanism.

In view of the HVAC and fan-coil system utilizing geothermal water whose temperature range is from 60°C to 85°C,the objective function of system has been established. The temperature parameters of all levels and the optimum recharge temperature of geothermal water are obtained by using MATLAB software. At the end of the paper, supply-water temperature of load side influencing on the price and coefficient of performance of high temperature heat pump have been analyzed in theory.

Choose a wavelet to transform the logging curves, which can obtain a series of scale and depth corresponding to wavelet coefficients. From the view of fourier series expansion and spectrum energy, the wavelet coefficients of optimal scale should be the largest proportion of total spectral energy. Based on the theory above, method of average modulus based on wavelet transform is put forwarded. Find the optimal scale factor through wavelet transforming of logging curves, and establish a correspondence between oscillations characteristic of wavelet coefficients curve of the optimal scale factor and sequence stratigraphy boundaries. This method provides a new way to recognize sequence stratigraphy boundaries.

Spherical cap harmonic (SCH) theory has been widely used to format regional model of fields that can be expressed as the gradient of a scalar potential. The functions of this method consist of trigonometric functions and associated Legendre functions with integral-order but non-integral degree. Evidently, the constructing and computing of Legendre functions are the core content of the spherical cap functions. In this paper,the approximated calculation method of the normalized association Legendre functions with non-integral degree is introduced and an analysis of the entire order of associated non-Legendre function calculation is presented. Besides, we use the Muller method to search out for all intrinsic values. The results showed that the highest order of spherical harmonic function for constructing regional model of fields is limited, thus high-resolution spherical harmonic structure of local gravity field need to be improved.

The mutation and form of logging curve can be represented by the variation of modulus maxima coefficients of wavelet transform within different scales exactly, then we can use wavelet multiscale edge detection theory to analyze characteristics of sequence stratigraphy boundaries in logging curves. Obtain the modulus maximum of approximation coefficient matrix and detail coefficient matrix after decompositing GR and SP curve in every scales.Compare and amend the modulus maximum of approximation coefficient matrix and detail coefficient matrix reciprocally, applicate the Mallat alternation foldover algorithm to reconstruction logging curve eventually ,we can get the fusion curves in different scales. The fusion curves can greatly enhance characteristics of sequence stratigraphy boundaries in logging curves.

Treating high speed milling theory as the guidance, this paper researched high speed milling process of bracket part based on Pro/E. Combined with the structural features of bracket part, three dimensional model is built by Pro/E and machining processes are worked out after analysis. Pro/E module was applied to fabricate tool paths. At last, finite element analysis method is introduced to study the processing deformation by Pro/E module, based on which measures to restrain processing deformations is advanced and processing sequences are optimized.

Due to the low design standards when constructed, limited construction materials, corrosion damage from natural environments and degeneration in normal use process, some reinforced concrete silos put up in the 1980s and 1990s are facing the troubles like decrease of bearing capacity, cracks and component damages, which are seriously affecting their normal use and bring certain security risks. Thus, the strengthening of these silos should be taken into account. In this paper, the positions that should be paid more attention when strengthened are obtained through finite element method analysis of a silo. Then the silo is strengthened with carbon fiber sheet through three different reinforcement conditions. The structure performances after being strengthened are analyzed, and the factors that affect the reinforcement effects are summarized.

In consideration of the deficient study on dynamic response of reinforced concrete silos, especially group silos at home and abroad, taking the silos of one grain storage for instance, the dynamic response analysis of a single column-supported silo and that of group silos are carried out and contrasted through finite element method. Then the analysis results are contrasted with corresponding standards as well as academic studies.

Coping problem is closely related to mental adapt and mental health. Coping style is an important mediator in physical normal college students’ mental stress, which affects students’ mental health. Based on a lot of documents, specialist interviews and questionnaire physical normal college students’ coping style features. Discuss physical normal college students’ methods of coping style in problem of life and study.

The material characterization and mechanical behaviors of aluminum alloy (6063) were investigated using flat specimens and the butterfly specimens with a modified Arcan fixture. The butterfly specimens were tensile-loaded at various stress triaxiality by changing the loading angles of the Arcan fixture. The flat specimens were tensile-loaded at various strain rates. The results of tensile tests at various stress triaxiality showed that the curves of engineering stress-engineering strain are obviously different. The results of different strain rates tensile tests showed that the yield stress and fracture stress increased slightly with strain rates increasing, however the fracture strain decreased obviously with strain rates increasing, and the ultimate strength almost remained constant. The Johnson-cook constitutive model could be used to describe the dynamic axial crashing behavior of thin-walled 6063 aluminum alloy tubes under impact loading. The material constants of the Johnson-cook constitutive model and failure model were acquired to be used for FEM simulation through material characterization.

The seismic response of the asymmetric structure isolated by the friction sliding bearings is carried out. The eccentricity and the torsional stiffness of superstructure are taken into account. The eccentricity and the torsional stiffness of the superstructure have less effect on the horizontal response of the base-isolated structure, but these have significant impact on the displacement at the corner of the superstructure and the rotational response of the structure.

The nano-scale indium tin oxide (ITO) particles are synthezed by liquid phase co-precipitation method under given conditions with solution of indium chloride, tin chloride and ammonia. The absolute ethyl alcohol or deionized water was used as solvent and the dodecylamine or hexadecylamine surfactant as a dispersant in the reaction system. The sample powder was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and high resolution electron microscopy (HRTEM). Based on the transmission electron micrograph， the influences of the two different solvents and the two different dispersants on the nanoparticle size and dispersion were studied respectively. The results shown that the ITO particles are finely crystallized body centered cubic structure. The particle size has distributed in 30nm to 90nm.

In this article a method of high speed scanning in Electron Beam Selective Melting (EBSM) technology is presented. Based on the conventional point-to-point vector scanning method, a scanning method nominated profile vector scanning was developed in cooperation with the existing manufacturing system. A scanning speed up to 200m/s was realized using the improved system. 3D parts from 316L metal powder were fabricated using this scanning system and the quality of the fabricated parts was evaluated.

Removed due to plagiarism. The original paper was published as http://onlinelibrary.wiley.com/doi/10.1002/1521-3765%2820001117%296:22%3C4082::AID-CHEM4082%3E3.0.CO;2-S/abstract

The effects of inoculation on the damping property of Mg-8Zn-4Al-0.3Mn alloys have been investigated. The results show that the damping property of ZA84 alloys reduces at room temperature after the addition of RE, whereas the damping property at high temperature increases obviously. The damping property of ZA84 alloys at room temperature and high temperature improves respectively after the addition of Al5TiB. It has reached Q-1=0.01 at room temperature with 0.25% Al5TiB. There exists a damping peak in all alloys at high temperature because of the viscous sliding of the grain boundaries and the inteneration of φ (Al2Mg5Zn2) phase at high temperature. It was found that the addition of RE could delay the temperature of damping peak occurs. The main damping mechanisms of ZA84 magnesium alloys with RE and Al5TiB additions are the dislocation damping and interface damping. The higher the movable dislocation density is, the finer the grains are and the more the grain boundaries and phase interfaces are, the better damping property of ZA84 alloys is.