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By the analysis of reinforced concrete slab, combined with experiment tests the feasibility of damaged plasticity model for concrete. Using parametric analyses, further the plastic damage model of related parameters set methods were discussed, concrete dilatation Angle, viscous coefficient, tensile stiffness, tensile damage on the results, in order to the design of slab-column connections engineering personnel to provide the reference.

The remote sensing technology can accurate inverse the aerosol optical depth so as to demonstrate the haze distribution. Taking the moderate resolution imaging spectroradiometer (MODIS) remote sensor data as the data source, the aerosol optical depth of Shanghai area on December 6, 2013 is inversed from the use of second simulation of satellite signal in the solar spectrum (6S) and NASA V5.2 algorithm, and then the formation has already been analyzed from the three aspects of human activities, weather situation and foreign pollutants. The results show that the inversion aerosol optical depth from MODIS remote sensing image gradually decreased mainly from northwest to southeast, and the foreign pollutants plays the leading role in this haze pollution incidents in a certain weather condition. It can provide the references for haze pollution monitoring and early warning using remote sensor data.

Aiming at the demand for timelines, effectiveness and retroactivity in the complex product assembly, this paper puts forward a kind of barcode-based material flow control technology. This technology regards the idea of complete kit as guide which, on one hand, puts forward a closed loop control mechanism including rapidly kitting pallet preparation, field scan confirmation and retrospective statistical distribution service-oriented material flow control. On the other hand, this paper puts forward a material complete kit which forms a complete set technology of assembly planning driven. This paper realized the dispatch of correct material in the correct time and in the correct way. This paper forms a process-oriented material trace statistics technology and solves the classification statistical issues of material status and location. Finally, this paper develops a prototype system and then the effectiveness of the technology was verified.

Study on the deterioration of the constant current remote feeding system throughout the life of the structure is always one of the most important issues in seafloor observatory network reliability engineering. Relationship between current-to-current convertor subsystem and amount of loads in branch line is described by introducing failure rate factor. Multistate reliability model of remote power feeding system has been set up and solved by genetic algorithms. Simulation results show that as the load configuration in trunk line and branch line changing, there exists best combination maximizes the system reliability, besides, appropriate increasing amount of loads in branch line can optimize the preventive strategy.

Three-axis processing of laser inner engraving machine control system can carry on multi-axis linkage control. Furthermore, it ensures multi-axis of high feeding speed and trajectory control of high precision. This article introduces the design of laser inner engraving machine movement control system. The core is a digital integrator of linear interpolation algorithm to generate the desired trajectory and control XYZ axis linkage. Wide speed range of servo motor and position detector resolution is adequate to constitute a half-closed loop drive. With integral separation algorithm being introduced in the controller, the speed of numerical control system, track speed and positioning accuracy are guaranteed in order to achieve optimal specification for dynamic and static characteristics of the whole system.

The loop controller of double position fully closed makes the AC servo drive system acquire a very high position accuracy and speed following which is hard to be achieved for time-varying parameters, load disturbance, AC motors and severely nonlinear controlled objects. For the system, the dynamic nature can be ensured by the inner position loop adopting PI regulation of half closed loop structure, while the stability and the immunity can be achieved by closed loop structures with the rings outside adopting dual-mode fuzzy control. This article analyzes the cause of positioning errors for servo motor and semi-closed loop structure. The article also explains how to design a two position closed-loop servo system based on fuzzy control by adopting the AC servo motor drive, the motor shaft back-end incremental photoelectric encoder to form the inner position loop and using the motion control card, the inner ring of servo system and the work platform of grating ruler to make up the outer position loop. Based on double position loop composed of three-dimensional laser processing gear, the accuracy of the three-axis linkage workbench position control and the speed following can be ensured, thus meeting the requirement of the laser subsurface engraving machine for high speed and high precision motion.

With the development of ubiquitous computing, augmented reality (AR ) technology has become an important research direction. For its Unique properties, it can be used in many engineering areas, especially in biomedical engineering. In this article, we mainly summarized the technical feature and technological superiority of the AR technology, and gave some applications and effectiveness of AR-based biomedical Engineering. This will be helpful for those who are eager to use this brand new technology in medicine.

In this paper,the mechanical properties of rock experiencing the variation of joint tip distance from sample end under uniaxial compression condition were simulated.Numerical simulation for the different rock sample in the uniaxial compression have been conducted to evaluate the effects of joint tip distance from sample end on the overall mechanical behaviour of jointed rock masses. It was done using the Rock Failure Process Analysis program RFPA2D. Numerically simulated stress-strain curve, peak stress, peak strain and failure patterns were compared with the corresponding physical tests. We found that specimen joint tip distance from sample end corresponding value (distance from the crack tip to the compression surface) linear relationship with the compressive strength values .Numerical simulations agree well with physical results, it is shown that RFPA2Dis suitable for the analysis of joint tip distance from sample end effect on rock fracture.

Getting the real-time information of spatial data, height and length of weld bead is the key point during the process of grinding and polishing large-scale part. To tackle this problem, a robot visual system is completed by building the double CCD and the laser on the mobile robot. Combining the image search algorithm with the image preprocessing algorithm in time domain, the laser single pixel feature line is obtained. The positions of each point in feature line are optimized by curve fitting so that the right spatial data and dimension are obtained. The result shows the proposed method can provides the precise information of weld bead, and the accuracy of measurement is within 0.15mm, as steady as repeatability.

A new element-free formulation of Kriging interpolation procedure based on finite covers technique and Kriging interpolation method which integrates the flexibilities of the manifold method in dealing with discontinuity and the element-free features of the moving Kriging interpolation. Two cover systems are employed in this method. Mathematical cover of the solution domain under consideration are used to construct shape function and physical cover is used to reproduce the geometry of the solution domain. The mathematical covers can take any types of shape and is much easily formed compared with those in the conventional MM. The presented method can overcome some difficulties in conventional element-free Galerkin methods in treating discontinuous crack problems. The fundamental theory of this procedure is illustrated and numerical analyses of examples show that the proposed procedure is an effective and simple method with higher computational accuracy.

This paper is based on the basic principles of the extended finite element in the large commercial software ABAQUS on the platform of different fracture energy of three point bending test of concrete are numerically simulated, and three-point bending crack initiation, through expansion path analysis. The results show that has a direct impact on the size of the fracture energy of concrete specimens destruction, Fracture of brittle fracture can be small more obvious, produce more harmful. When softening decline stage after peak stress occurred in the "jump back" phenomenon.

This paper is mainly based on the basic principle of the extended finite element ,in the large commercial software abaqus on the platform of dynamic load eccentric mixed-mode of concrete failure process are numerically simulated, the results showed that the crack together under tension and shear ,crack extension direction and the direction of cracks was obvious deflection, and is in good agreement with the physical experiments, also shows that the extended finite element fracture problems have very good advantage.

A portable mind wave monitor which is a special made headband for intellectual disabled children is proposed. The headband could make the children easier to be understood by the teachers and researchers. The EEG (electroencephalogram-graph) sensor, live camera, microphone and a series of sensors is consisted in the headband. With the Wi-Fi or 3G network, the headband could connect to server though the internet at any time. The teachers and researchers can access on the website or apps on smartphone to manage the children daily testing data. Intellectual disable children always have low self-control ability, limited language ability and self-associated complications, and this system meets the special needs for the teachers and researchers. This headband enable teachers and parents have the same perspective as the intellectual disabled children.

The direct-drive servo motor is servo product with high performance widely applied in the fields of robotics and manufacturing due to its special construction and high-precision design. Considering the working principles of laser engraving machines, as well as the impact on the dynamic and static performance of the control system exerted by PID controllers frequently integral correction link in the process of start and stop, this article describes in detail how to achieve accurate positioning of direct drive servo motor by adjusting PID parameters. Key Words Servo motor,PID variable structure,Servo positioning,Laser engraving machine

CR-InSAR is developing continuously in recent years. It is an important technology in the field of monitoring crustal micro-deformation. Radar cross section of corner reflector is an important work foundation because only radar cross section of artificial corner reflector achieves maximum, it is easier to recognize it from SAR image and increase monitoring accuracy. Dihedral corner reflector is the simplest type in proving ground of Northwest of Beijing; its RCS research is a beneficial attempt helping to build up reasonable corner reflector layout. In the paper, establishing geometric model and subdivision model of dihedral corner reflector are based on FEKO software, and choosing physical optics to simulate RCS. The simulation result is good consistency with theoretical max value. Through analyzing RCS curve, it can help to provide guidance on how to set up corner reflector in the proving ground.

This paper presents a low luminance dynamic range converter that includes light recording and adjustment system for vehicle application under light insufficient environment. The development of vehicle electronic technology has improved traditional vehicle function. How to design a safety function system for vehicle become more and more important in vehicle industries. This work designs low luminance dynamic range converter circuit for vehicle application and provides a safety-driving environment. In the proposed method, we adopt video capture system to record light information from driving environment. An adaptive adjustment is adopted to re-arrange the histogram according to the distribution of luminance. Then, we use a series of test images and extract the characteristic value to train the system to reflect practical circumstances. Next, color calibrations and de-noise processing are performed to improve the visual quality. The presented approach considers the realistic driving situation and provides a bright and safe visual environment for driver under light insufficient environment.

In this paper, we propose a three dimensional vision conversion based on cloud computing. Three dimensional video and image system become an important technology in consumer electronics field in latest decade. There are numerous three dimensional video and image formats for different 3D products. However, the three dimensional vision contents that are manufactured by different standards are difficult to exchange without complete three dimensional vision converters. Therefore, how to perform the three dimensional vision format converters to interchange different kinds of three dimension vision becomes an important research topic in academic and industry. Nevertheless, three dimensional vision processor and converter have high computing complexity. It is hard to perform whole three dimensional vision converter according to all kinds of international standards in client machine and portable device. At the same time, three dimensional visions often require a large number of storage spaces. It is also very difficult to record all kinds of three dimensional visions in local device. The above problem should be solved adopting different concepts. Therefore, we proposed cloud computing concept that establishes a complete three dimensional vision converter in cloud computing server and storage space in three dimensional vision clouds. The customer access the three dimensional vision rely on three dimensional vision cloud. The approach methodology solves the problems of computing complexity and storage space of tradition three dimensional vision converters and storage. The presented intact framework of three dimensional vision converters also provides a solution of related research in this paper.

Presented in this paper is a new element-free formulation built shape function using moving Kriging interpolation method instead of moving least squares method. The merit of the proposed method is that the shape functions constructed using this method have the property of Kronecker δ-function property which made the essential boundary conditions be easily implemented. The fundamental theory of this procedure is illustrated and numerical analyses of examples show that the proposed procedure is an effective and simple method with higher computational accuracy.

The measurement of the teeth surface and the CAD modeling of the point cloud data are the key basics for the following CNC machining, and the complete data can only be obtained through multi-perspective scanning method. Using ICP iteration algorithm that based on point-to-line to the multi-perspective scanning data, specific to the features of layering scanning, retrograde the 3D data registration to 2D planar registration, and provide the cutting and splicing algorithm for registered tooth data, obtain precise and integrated tooth surface point cloud data, which serves as the CAD model for the following CNC machining.

The STL (Stereo Lithography) model is based on the triangular facets of 3D surface description model. This article studies the processing cutter path calculation of the STL model sculptured surface manufacturing: It proposes the full grid quad-tree partition method for surface of the triangular grid model. The sculptured surface is classified by quad-tree partition with projection plane for cutter location point calculation to give a fast search algorithm. Take tooth surface for example, the feasibility of the algorithm is verified according to the study of cone-shaped cutter tool path generation algorithms and also by the grinding test.

In this paper, we propose an interactive remote control system using image processing technique for three dimensional displays. In order to control three dimensional displays, we present an algorithm based on gestures recognition. Then we adopt cell-based design flow and 0.18μm TSMC single poly and six metals processing to perform the system chip. Besides, the SMIMS FPGA development board is used to achieve the system. The results prove the performance reaching the well quality of interactive remote control system for three dimensional displays.

In 3-axis NC machining, most algorithms of the sculptured surface tool-path generation are valid for ball-cutter, and the axes are designed to realize pure translation. A tool-path generation algorithm using taper-cuter is proposed in this article. And one axis of the 3-axis NC tool machine is designed to realize swing motion. The Stereo Lithography (STL) model is the most popular triangular mesh approximation of the 3D surface model. Considering the special swing mechanical and taper-cutter, arc-zigzag tool-path planning and deform Z-map grid methods are proposed, which incorporate triangular vertexes method and the Z-map method. Finally, some simulation and experiment results are provided.