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Image segmentation is the key step in image recognition,the result of segmentation affects the one of recognition directly.The article introduces the concept and detailed definition of the image segmentation. The segmentation algorithm of iterative threshold in detail. According to the intrinsic characteristics of weed images, just can use the iteration threshold segmentation method, and implements them by Matlab programme, then processes three weed images, respectively to obtain effective results , and establishes a good base for the pick-up of the target character.

It plays an important role in guiding laser remanufacturing process and process control to research temperature field of laser remanufacturing. A numerical simulation method of temperature field based on MATLAB PDE Tool is proposed. Theoretical model of temperature field is presented. The temperature fields at different times are calculated and simulated with finite element method and MATLAB software with PDE Toolbox. The results show that this method can accurately calculate the temperature distribution of the laser remanufacturing process. The simulation results are helpful to optimize process parameters and to improve the quality of laser remanufacturing.

The functions and approval test requirements of the GCS were introduced. The composition and working principle of DEWE 2010, a portable data acquisition system, were presented, which provides a feasible technological approach for software demodulation of AM signals in GCS testing. On researching the principles of AM signal modulation, two novel coherent and non-coherent software demodulation methods for AM tracking error of GCS were devised with mixed programming of LabWindows and MatLab. Test and simulation results show that the measuring accuracy and automation level of novel AM tracking error testing approach meet the requirements of test measurement.

This paper designed and implemented a desktop application of safety lock based on face recognition. The application is developed by C# and used open source visual library OpenCV and SQLite lightweight database. Principal component analysis (PCA) and Rijndael algorithm are respectively used in face recognition and algorithm of encryption and decryption. This paper illustrates design and implementation in detail

The deformation analysis of explosion vessel is very important in strength analysis and engineering design. By means of laser Doppler measurement and Wigner-Ville distribution, the expansion process of steel explosion vessels has been studied, and the frequency characteristics of the strain wave are analyzed. Finally, the experimental results of deformation and vibration frequency of vessel are given under the condition of 300g TNT explosion equivalent.

This paper presents a new approach for obstacle avoidance of small mobile robots, which combine the position sensitive detector (PSD) with digital compass. It is important for an autonomous robot to explore its surroundings in performing the task of localization and navigation for searching. Because of the complexity of the environment, one simple kind of sensors is not sufficient for robot to accomplish these tasks. In this paper, the small mobile robots are enabled to identify barriers and distinguish surroundings by using the angle signal from the digital compass which is generally mounted on the robot. Experimental results indicate that this approach based on digital compass shows great potential in autonomous robot obstacle avoidance.

To characterize the coarse-grained soil of the fillers in Zhijiang North station of Shanghai-Kunming Passenger Dedicated Line, the vibration compaction test was conducted to study maximum dry densities under different granular compositions. Considering the non-linear relations between granular compositions and maximum dry densities, a BP neural network prediction model of which the input layer was consisted of granular compositions, grading index and fractal index was established based on the backwards error propagation algorithm and the results of the maximum dry density tests. As was improved by the adaptive learning rate method and additional momentum method, the final model established in this paper performed well in predicting the maximum dry density of the coarse-grained soil of various granular compositions.

Test and adjustment system of coordinator (T&ASC) is, virtual instrument technology based, developed. PXI measurement control platform, turntable system, target simulator and air source equipment are integrated in hardware design. Multithreading, IMAQ Vision module and DLL techniques are used in software programming. Technical difficulties as synchronous receiving of RS422 data with high speed, direct display of LVDS video image and integrated control of turntable are solved. The system achieves the integrated design of test, control and adjustment function, which can carry out overall performance tests for coordinator automatically, and execute system parameters calibrating and adjusting intelligently.

Functions and features of servo system are, as well as composition and working principle of DEWE 2010 portable data acquisition system, introduced. Feasibility of using DEWE 2010 data acquisition platform to test rapidity performance parameters of servo system is analyzed. Identification method for rapidity performance parameters is given out by research of rapidity model and signal definitions. Parameters are, such as overshooting, fluctuation number and transferring time, defined for servo system. LabWindows and MATLAB co-programming method is used to realize automatic measurement of rapidity performance parameters. Test results indicate that the measuring accuracy and automation level of this method meet the test requirements.

Volunteer management is large sports games get a key element of success. This article through the literature data method, interview method and logical analysis, the characteristics of volunteers and the particularity of the large sports games was analyzed, With the success of Beijing Olympic Games volunteer management experience, put forward the large sports games volunteer management should stick to effective recruitment, multiple training, it is with the person this, dynamic adjustment, Multidimensional incentive, meet the demand, mutual equality, unity cooperation principle, with its large sporting events for the future volunteer management to provide the beneficial reference.

High-strength Cu-based bulk glassy alloys with a large supercooled liquid region in Cu-Zr-Ti-Ni systems were prepared by means of copper mold casting. The Cu-based bulk glassy alloys samples were tested by X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and Instron testing machine. The result indicates, the maximum diameter was 5.0 mm for the Cu55Zr25Ti15Ni5 bulk glassy alloy. The temperature interval of supercooled liquid region (ΔTx) is as large as 45.48-70.98 K for the Cu-Zr-Ti-Ni alloy. The Cu-based glassy alloys rods exhibited the very high mechanical properties and the distinct plastic strains. The compressive fracture strength is 2155 MPa, 2026 MPa and 1904 MPa respectively for Cu50Zr25Ti15Ni10, Cu55Zr25Ti15Ni5 and Cu54Zr22Ti18Ni6 bulk glassy alloys. The Vickers hardness is respectively 674, 678 and 685 for the Cu50Zr25Ti15Ni10, Cu55Zr25Ti15Ni5 and Cu54Zr22Ti18Ni6 bulk glassy alloys. The addition Co element to Cu-Zr-Ti-Ni alloy expand the ΔTx, the ΔTx is 74.5 K for Cu50Zr22Ti18Ni6Co4 bulk glassy alloys.

SpaceWire is a high-speed, full-duplex serial bus standard which is applied in aerospace, so its functions require high accuracy. The traditional methods of verification, such as simulation and test, are not complete. In order to prove the design of the SpaceWire faithfully implemented the SpaceWire protocol’s specification, we presented our experience on the model checking of SpaceWire data flow control using the Cadence SMV tool. It overcomes the incompleteness of traditional verification. And by injecting the errors to ensure the accuracy of the artificial extraction properties and completeness, comparison tests show that the method can effectively ensure the functional coverage, improve reliability of the verification.

Considerable attention has been devoted to prove the correctness of programs. Formal verification overcomes the incompleteness by applying mathematical methods to verify a design. SpaceWire is a well known communication standard. For safety-critical applications an approach is needed to validate the completeness of SpareWire design. This paper addresses formal verification of SpareWire error detection module. The system model was constructed by Kripke structure, and the properties were presented by linear temporal logic (LTL). Compared the verification of LTL with CTL (branch temporal logic), LTL properties could improve the verification efficiency due to its linear search. The error priority was checked using simulation guided by model checking. After some properties were modified, all possible behaviors of the module satisfied the specification. This method realizes complete validation of the error detection module.

Based on fractional nonlinear stable theorem, backstepping approach for designing controller is extended to fractional order chaotic system. The controller is designed to synchronize fractional order Newton-Leipnik chaotic system via the backstepping approach. Numerical simulation certifies effectiveness of the approach.

In this article, the mechanism of the effects of nano-TiO2 on the properties of automotive topcoat is discussed. Based on the original thought that nano-TiO2 may improve the aging property, a research is carried out into the effects of nano-TiO2 on the properties of automotive topcoat, and the formulation design of nano-TiO2 coating is optimized. The coating properties such as glossiness, adhesion, resisting impact strength, hardness, water fastness and resistance to aging are measured by experiments. The results show that with 1.0~2.0 percent of nano-TiO2 content, the aging resistance of the coating increases by approximaSubscript texttely 20 percent with higher glossiness, while adhesion, impact strength, hardness and water fastness are not meaningfully improved.

The blast-resistant performance of columns which are the most important component in the whole structure is a crucial factor which influences the safety of the structures subjected to the blast loads. Studying dynamic responses of RC columns under the blast loading and improving the blast-resistant performance can prevent the structure from progressive collapse due to the damage of the columns in the blast loading, and give people more time to escape from the building in a dangerous situation. Then the same parameters are used to analyze the dynamic responses of RC columns under three typical blast loads. Conclusion can be used for structure blast-resistant design.

To study the kinematic characteristics of a new designed flange vertical lathe with double machining tools, a virtual prototype model was developed in ADAMS with the help of PRO/E and MechPro, a seamless interface program between both mentioned software. And kinematic and dynamic simulations were carried out. The results of the simulations are consistent with the reality which states that the model was created correctly and the simulations were reliable.

With the optimization design method of FE,the FE model of vertical flange lathe beam of double-tool holder was established,the sensitivity analysis of dynamic performance for the machine tool was performed based on presented modal analysis and probability analysis.The influence rules of the first four natural frequencies affected by the design parameters of the lathe beam were confirmed and the weaknesses of it were indicated as well.Then, the structure of the lathe beam was optimized.As a result ,the dynamic performances of the lathe beam are improved and it offers the basis for the optimization design of the other lathe parts.