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In the paper, degradation and restoration model is introduced. Image restoration method using inverse filtering and using wiener filtering are studied and implemented. A new method of image restoration is proposed by combining histogram equalization and median filtering. Comparing three methods by MATLAB simulation, the results show that the new method can effectively restore degradation image with comparatively high restoration efficiency.

This paper based on the peculiarity of wavelet transform that its transform only in vacuum region and frequency region, decompose image use the theory of wavelet, obtain a series sub-image of different resolution ratio. The value of higeresolution ratio sub-image is all verge on 0, the phenomenon is more obviously in high frequency, so that, the mainly proportion is low frequency to a image. Use wavelet decomposition get rid of the high frequency, only reservation low frequency, to realize the aim of condensation image. Through the simulation of contradistinctive image of cerebra framework remotion between three-dimensional ultrasonic imaging in course of OPS and MIR preceding OPS validated the feasibility by Matlab.

Through analyzing Dabaoliang geological characteristics, this paper discussed the factors of the mechanism of landslide in Dabaoliang area and simulated its evolutionary process. The paper could get some conclusions, and the factors of landslide are as follow: the stability of the slope which mainly composed by clastic rock not only depended on the performance of the mudstone layer but also the skid resistance of the sliding surface and the shape of slope. Under the influence of regional structure, the joint fissures which developed along the boundary of the landslide will connect the crack and benefit the permeation of the surface water. The heavy rain is one of the main factors caused the slope unstable and sliding. Provide effective prevention and control for prevention and control of projects.

For the low contrast and serious noises, a fast image segmentation method based on one-dimensional gray segmentation, binary morphology erosion and area elimination is proposed. Since veins are thin and long, the vein image can be easily distinguished from background by judging the gray difference from nearby pixels when they are vertically or horizontally scanned. Then the processed image is diposed with erosion and area elimination to filter the noise. According to test results on the hand vein images which got from the equipment constructed by ourselves, it is proved that the method is more suitable for hand vein image segmentation than others and clear vein images can be botained quickly.

As a important tension member, high strength bolts having crucial effect for bearing capacity of grid structure. Especially for in-service engineering, when high strength bolt tensile load doesn’t meet the standard requirements, how to determine the structure bearing capacity influence is particularly important. The article is aimed at the situation of the design review and analysis, through the bearing capacity reduction, reducing the high strength bolt bearing capacity, and the reduction of bearing capacity and the actual force are compared, to determine the safety of the structure. Through the question processing, provides a discussion for solving the similar problems.

This paper investigates the synchronization of incommensurate fractional-order chaotic systems, and proposes a modified adaptive-feedback controller for fractional-order chaos synchronization based on Lyapunov stability theory, fractional order differential inequality and adaptive control theory. This synchronization approach that is simple, global and theoretically rigorous enables synchronization of fractional-order chaotic systems be achieved in a systematic way. Simulation results for a fractional-order chaotic system is provided to illustrate the effectiveness of the proposed scheme.

Existing Adaboost methods for face detection based on particle swarm optimization (PSO) do not consider that PSO suffers from easily trapping in local optimum and slow convergence speed. This paper presents an improved Adaboost method for face detection to solve this problem. In this method, self-adaptive escape PSO (AEPSO) is introduced into conventional Adaboost face detection, meanwhile, Haar-Like rectangular features are represented by particles, so that features selection and classifiers construction could be resolved by using AEPSO. Results of simulation based on Matlab indicate the improved method obtains better detection performance.

Feature extraction is a key point of text categorization[1]. The accuracy of extraction will directly affect the accuracy of text classification. This paper introduces and compares 4 commonly used methods of text feature extraction: IG (Information gain), MI (Mutual information), CHI (statistics), DF (Document frequency), and proposes an improved method based on the method of CHI. Experiment result shows that the proposed method can improve the accuracy of text categorization.

The engineering vehicle cab FOPS (falling-object protective structures) mainly contain two parts: top guard and front guard. According to the characteristics of the engineering vehicle cab security architectures, the simulation that top guard is impacted by the falling hammer is made by non-linear analysis software – LS-DYNA. The breakage phenomenon is also researched. The stiffness of the top guard is so weak that the hammer’s displacement is too large, which leads to the impact resistance of top guard is unqualified. Based on this, the cause of the stiffness insufficient is researched. By orthogonal experimental design for the dominant factors, it makes the simulation performance of the top guard meet the requirements of the national standard. On this basis, the simulation mechanical bearing capacity of the front guard is done by LS-DYNA, while the experimental research is also accomplished. By contrasting the result of simulation and experiment, it turns that simulative result coincides with the experimental well.

There are often complex dependency relationships between systems in a system of systems (SoS), which present great challenges for SoS operability analysis. Functional Dependency Network Analysis offers the capability to evaluate the effect of both topology and of the possible degraded functioning of one or more systems on the operability of each node in the SoS. But there are some insufficiencies in the method, so here we give exact definition to self-effectiveness, which includes absolute self-effectiveness and relative self-effectiveness. Then according to the new definitions we show the detail calculation equations. Finally we we take the application of Guariniello and DeLaurentis’s five-node aerospace network for example, and compare the results with theirs. Comparative results show that their results are larger than the exact outcome, and our version give the authentic outcomes.

Applling Leeb hardness tester D punch, examined the steel hardness by two different ways of clamping method and coupling method respectively, studied the correlation of Leeb hardness and steel strength, compared the research results with related literature and Jiangsu province construction standard of DGJ32/ TJ116-2011. Through the research, the conclusion is larger that this research results and related literature, the reliability is very low which be used to infer steel tensile strength with the D punch testing Leeb hardness .

The definition for the constellation availability of the navigation system is given firstly, and then calculates the availability of a single satellite by using Markov processes, and establishes the model based on the state probability of the constellation, to achieve mapping model from component reliability of the single satellite to the constellation availability. Finally, we analysis the regional availability performance of the GNSS by the algorithm, which can fit and satisfy the requirements of contradiction between accuracy and rapidity for analysis of availability for constellation of GNSS.

Water inrush from coal floor is some kind of complex geology and mining phenomenon. It is the confined water underlying the coal seams breaking the barrier of the bottom layer, and the water runs into the face of mine in emergencies or delayed, causing natural disasters like discharge increases or flooding. According to the previous studies on water inrush, the water inrush is a joint result of geological structure, water pressure, mine pressure, water-resisting floor and mining of working face. The thesis focuses on the influence of geological fault on the water-inrush from coal floor and analyses the controlling effects of fault property and non-water conducted fault activation of water in order to provide a reference or significance for the analysis of water-inrushs genesis mechanism.

This paper present a way of pulmonary interstitial pathology diagnosis of computer-aided diagnosis based on wavelet analysis. It is difficult to diagnosis qualitatively in pulmonary interstitial pathology because various lesions of the image analogous and the image interlap. The method based on good time-frequency characters is put. The effectiveness and accuracy of the means is verified through the simulation experiment of denoised image, image segmentation and image characteristics extraction. Along with the further research and application of the wavelet technique, it will have more space that use wavelet analysis in computer-aided diagnosis.

Satellite navigation systems are running in complex electromagnetic and space environment. There is few research studies the threat and protect ability of navigation system. Lacking of qualitative data makes it difficult to analyse the security of it. In this paper, we applied Functional Dependency Network Analysis (FDNA) to solve this problem. FDNA studies how the impact caused directly by attack spreads in the overall system through the dependencies between function nodes of system. Then we are able to assess the operability of the application of navigation system. This method avoid considerable statistic experiments. Make full use of principle data. Provide constructive decision making comments.

The civil communication system in urban rail transit network is the one which can provide the passenger value-added service. It can meet underground needs of information service for passengers, and be the alternate means of communication for drivers, equipment maintenance personnel, the stations duty officers, and so on. When the wireless systems for rail transit comes malfunction, the civil communication system can provides smooth information channel for rail transit participants to ensure the safety of personnel and rail transit dispatching.

Parameters monitoring and risk management is more and more important and necessary for Tunnel Boring Machine (TBM) along with strata and environmental conditions are becoming increasingly complex. The accurate and real-time monitoring of TBM construction process is the basis of security for structure, environment and avoiding the engineering accidents. However, almost all existing TBMs only have the functions of data collecting and storing, how to use these data to monitor and evaluate the status of TBM advancing in real-time, as well as realize the functions of risk prediction and management are still a continuous research problems. In this paper, Risk Monitoring System for Tunnel Boring Machine (RMSTC) has been researched and developed to monitor the process of TBM tunneling and manage the construction risks. The engineering practices show that the RMSTC is a safe and credible system which can achieve data transmission, parameters analysis and material consumption statistics in real-time, and it offers a new efficient way for risk recognition, analysis, evaluation, prediction and control.

Based on Wagner field cancellation method, the paper presents a simplified method to calculate the induced overvoltage on transmission lines excited by lightning striking on tower. Firstly the square-wave response of lightning-induced voltage is calculated, and then the responses produced by other excitations can be calculated by Duhamel integral. This method can reflect the time-varying characteristic of the induced overvoltage. The simulation results show that the amplitude of lightning current and the length of upward leader have greater impacts on the induced overvoltage.

A refined theory of transversely isotropic beam posting inside Winkler foundation is derived without ad hoc assumptions. Based on elasticity theory, the displacement field and stress states of isotropic body are studied. From boundary conditions, the refined theory of transversely isotropic beam posting inside Winkler foundation is given. The approximate equations for the beam under transverse loadings are derived directly from the refined beam theory.

The objective of the study is to evaluate visual fatigue induced by different tablet PCs (LCD/OLED) by measuring CFF (critical fusion frequency), BF (eye blink frequency) and (SR) subjective rating. Twelve healthy subjects (10 males and 2 females) participated in the study in a controlled simulated living environment with a 18-23°C temperature, 30-45% relative humidity and 150lx illuminance. The experiment was carried out about 50 minutes, including: 30 minutes watching task (EOG test) and 20 minutes test (including subjective questionnaire and CFF test before and after the experiment). The experiment design included dependent variables: CFF, BF and subjective rating (SR); and two independent variables: Tablet PC types, watching times. As a result, after the experiment, the decline range of CFF of LCD was lower significant than that of OLED (p

This paper presents the architecture and implementation of a H.264 decoder SOC system. The SOC system has mixed hardware arithmetic unit and software instruction based on co-processors, which are designed by analyzing the major arithmetic units of H.264 decoder. The co-processor approach can meet certain performance requirement with high scalability, which can be easy for system upgrade and expansion in the future. The verification result shows that the SOC system can speed up H.264 decoding process by saving more than 75% of the decoding time.

This paper presents a Smart Farm system, which is based on Ultra Narrow Band (UNB) communication technology. As to the characteristics of large area and high livestock mobility on the farm, using traditional communication technology have the problems of high cost, high power consumption and difficult power supply, however, UNB can achieve a high spectrum utilization efficiency and reduce the power consumption. At first, this paper introduces the Minimum Side-Band (MSB) modulation technology which is one kind of the UNB technologies. Secondly, the key issues of digital demodulation is discussed. And then, a MSB transmission system include digital modulation and demodulation is designed and simulated. Finally is the design of Smart Farm based on UNB technology and the summary of the whole work.

This paper mainly description image enhance based on wavelet transform. The author gave the theory of wavelet analysis, the application of wavelet transform in image enhancement. The impression drawing is given by means of MATLAB simulation. Through tone up to disperse wavelet transform, rebuild coefficient, the siginal of image is more boost up in low contrast section than high contrast section, the margin is distinct.

In the Yellow Sea, two large terrains of tidal sand ridges developed, respectively, in the Subei Shoal and the West Korea Bay. Sediment supply, hydrodynamics and bedforms are critical factors to form them. In this paper, sediment composition, morphology of sand ridges, etc. are analyzed in terms of relevant factors and subsequently their formation mechanisms and evolution processes are careful compared.

Firstly, this article focous on the requirements for RFID antenna of ecommerce--a fractal design of folded dipole antenna by moment method for simulation analysis of the designed antenna, the return loss performance of the antenna are calculated. In order to have more redundancy for the performance of the antennas in actual use when in all kinds of bad environment to function properly, we try to use methods of additional passive patch, microcosmic fractal structure and mirror compensation structure to improve the performance of the antenna. Then we compare the effects of multiple antenna performance improvement methods, and find the best optimization design project. According to the design of antenna, it’s resonant frequency is 2.4GHz, the minimum return loss value is -46.27dB, the bandwidth is 544MHz. Secondly, in view of the engineered practice, the article also discusses the influence of substrate parameters on the performance of the antenna in detail.

On the basis of the measured ground borne vibration of some inter-city express railway viaduct, test results analysis shows that: the test environmental vibration is under the limit set by standard of environmental vibration in urban area; whether transverse or vertical vibration, a rapid attenuation of the peak acceleration with the distance to the up-track center is observed, however the vibration at 7.5m appears to be amplified; the ground vibration with the distance conforms to a logarithmic relationship; the horizontal ground vibration at 7.5m caused by the elevated rail transit is larger 3.6cm/s2 than the vertical vibration; low-frequency vibration transfers farther than high frequency vibration; the eccentric effect of two-track viaduct is obvious.

When a train runs across a bridge, vibration energy is transmitted from the track structure into the bridge deck and other components which act as different size of ‘sounding boards’. These ‘sounding boards’ also radiate noise, namely, re-radiated noise, which results in ‘hot spots’ in noise maps for bridge sections. Based on the field tests on the noise of 32m double line simply-supported PC-box girder serviced in Chengdu-Dujiangyan High-speed Railway (CDHR) in China, mathematical logarithmic equation for predicting the equivalent A-weighed noise level (LA,eq) is proposed. Predicted results are compared with field ones and the non-parametric tests including two-related samples Wilcoxon and two-independent samples Kolmogorov–Smirnov are carried out, indicating satisfactory results and verifying the reliability of theoretical model. Analysis shows that equivalent A-weighed noise level detects no significant difference between the model predictions and the field measurements at the confidence level of 95%.

During rehabilitative training, a 3-DOF wire-driven parallel robot driven was designed to coordinate and control the trainer pelvis movement. Based on the force balance equation of the end-effector, the stiffness problem about the robot system was analyzed and one kind of force/position parallel control strategy was proposed that the position loop would realize the end-effector motion trajectory, and the force loop would control the wire tension. The experimental results have shown that the robot systematic stiffness is related with the wire tension and can be changed to realize the compliance control of the robot system by adjusting the wire tension.

Screw pump is a special type of rotary positive displacement pump in which the flow through the pumping elements is truly axial. The objective of this study is to develop a numerical solution method for flow analysis of a twin screw pump by using a Single Rotating Reference Frame method with various boundary conditions and rotational speeds of rotor on steady state condition. Flow variable contours and plots were obtained for fluid flow inside a pump subject to pressure inlet and pressure outlet conditions using the numerical control volume method in the commercial package of FLUENT. This work needs for the analysis of flow parameters inside a screw pump in order to achieve optimum design.

The emotional demand of modern consumers is analyzed and it is pointed out that products based on appealing design will be widely accepted and needed by people. Under the consideration of design originality and availability, five innovate methods are concluded to instruct the product appealing design which are bionics design on product shape or character of bionics in shape, idiographic design of materials, fun character during using experience, artistic character of market positioning and the feasibility of product customization. During the dissertation of above innovative methods, some excellent products are exampled to enlighten and verify the research conclusions.

On the base of comprehensive analysis of some new single-track seismic profiles and logging data, the neotectonic movement characteristics of the northern East China Sea Shelf Basin are researched. In the study area, there are intensive neotectonic movement. The main manifestations of the neotectonics include vertical movement, fracture activity and magma activity. The research indicate that the sedimentation centers shift from west to east since Miocene. NE-NNE-striking fault and EW-striking fault are the main active faults. The activity of these faults are gradually later from west to east. The magma activity are frequent and can be divided into three phases in the neotectonic period . They are mainly distribute along active faults. From west to east, the magma activity phases are gradually later. The intrusion gradually weaken and eruption gradually strengthen.

Path planning for mobile robot is a kernel problem in the robot technology area, with the characteristics of complexity, binding and nonlinearity. On account of global path planning for mobile robot in static environment, this paper discussed a method of combining ant colony algorithm and genetic algorithm. After completing a cycle of ant colony algorithm, two paths ants walked were randomly selected, and these two paths were further optimized genetically on the basis of certain crossover rate, if more optimal paths were obtained, the pheromone would be released in the more optimal paths, by this method the diversity of solution could be increased and solution speed be improved. The simulation result has verified the effectiveness of the proposed method.

Deformation memory effect (DME) is one of the rock memory effects. One important application of the DME is to determine the in situ stress. The in situ stress measurement methods based on the DME are commercial and permit large number of measurements. Application of DME needs the reliable and effective identification methods to detect the DME. However, the existing identification methods are insufficient and not distinct. In this paper, a new method based on fractal dimension was proposed. It takes advantage of the increase of the irregularity of the stress-strain curve after the previous maximum stress attained. Numerical models for the sandstone and granite were developed based on the contact bond model in PFC2D. Fractal dimension method was employed to detect the DME for two types of the rock. The results demonstrate that the fractal dimension method is effective and reliable in the identification of DME in rock.

In this paper, the elasto-plastic dynamic analysis on the steel spatial arch truss with 90 m span and 0.3 rise-span ratio is carried out under earthquake wave with SAP2000. the geometric and material nonlinear effects are considered during the analysis simultaneously based on the plastic hinge theory. Under the action of EL wave with the peak increasing gradually, its elasto-plastic dynamic responses have been obtained. The results show that its failure mode under the earthquake action is elasto-plastic dynamic buckling; that its critical peak acceleration of EL earthquake wave when applied in horizontal direction is 363 gal, and is 408 gal when applied in vertical direction; The ratio of its maximal node horizontal displacement and its structural height is 1/796, and its displacement ductility coefficient is 1.06 and the ratio of its bars with plastic hinge appearing when buckling is 0.96% when EL-Centro waves applied on structure in horizontal direction; The ratio of its maximal node vertical displacement and its structural span is 1/1418, and its displacement ductility coefficient is1.12 and the ratio of its bars with plastic hinge appearing when buckling is 1.28% when EL-Centro waves applied in vertical direction.

Matlab anonymous function method combining graph with analytical method was proposed in this paper, which was based on the low solving efficiency and low precision of trigonometry transcendental equation for shape line design and sectional profile calculation of screw pump rotor. Parameters of anonymous function can be nested within each other to solve enveloping conditional formula of shape design or intersecting line of sectional profile design for screw pump, the process of which only took several seconds with high precision of 10E-08mm. What’s more, this method could also be adopted in the forming tool design with spiral cross section, which could largely improve design efficiency and calculation precision.

Aimed at the problems of logarithmic spiral blade mixing unequally and square spiral blade discharging in slow speed, a new method for deriving mixing drum spiral blade was proposed based on the principle of differentiation, deducing both logarithmic spiral and square spiral. Combined with actual demand, a new type of mixing drum spiral blade was designed. Compared with traditional spiral blade, helical lead angle of the new spiral became smaller in a certain range. The variation scope of pitch and taper section diameter were more reasonable, and then the mathmatical model of new mixing drum had been established.

A robot system is present for the wind turbine blade grinding work. The robot is a mobile manipulator equipped with a grinding tool. In order to realize the compliant control of the operation force, a robust impedance controller is present in the presence of coupling factors between the mobile platform and manipulator, modeling uncertainties and existing bounded disturbances. The proposed control strategies guarantee that the system motion converges to the desired manifold and the desired constraint force. Simulation experiment has been done and the experiment results show that, the presented control method can realize the robust control of mobile manipulator, and thus show the effectiveness and correctness of the designed controller.

A mobile grinding robot is present here for the wind turbine blade grinding work. The robot is a mobile manipulator equipped with a grinding wheel. A mobile manipulator robot is built up with a mobile platform and a robotic arm mounted on it. The dynamic model of the robot is built, and the dynamic model of the two subsystems is derived from it, so the dynamic coupling items can be deduced. In order to discover how the coupling force influence the robotic manipulator, the SimMechanics model of the robot is built up and the simulation research is carried out by the built model. The results show the influence of coupling force on the manipulator.

Molding parameters are significant for compression molding. In this paper, the molding process for low pressure sheet molding compounds thickened by crystalline unsaturated polyester was investigated. The optimal molding parameters such as molding temperature, molding pressure and curing time were determined by orthogonal test. And the effect of molding parameters on flexural strength and surface quality of molded parts were also studied. Results showed that when the molding temperature was 115°C, the pressure adding time was beginning at 15s after LPMC was put into the die cavity, the moving time of press column was 15s at the last 25mm and the pressure keeping time was 6min, LPMC gained optimal mechanical property and surface quality.

There have been more and more types of electromechanical products which is detected and controlled with computer aided techniques, and also they have been more and more automatic. In order to learn and design a system to measure and control electromechanical products quickly, this paper developed a comprehensive test-bed to measure and control parameters. It combines VC++6.0 programming environment, MATLAB and PCL-818HG data acquisition card. This thesis introduced how to examine the displacement, rev, temperature, stress and the scheme of hardware composition to control the rev of engine. It also introduced the multi-threaded programming of VC++6.0 and the development methods of establishing link libraries between MATLAB and PCL-818HG. There were some applications as well.