A 3-DOF nonlinear dynamic model of vehicle is established as nominal model of vehicle state and parameter estimation. Strong tracking Central Difference Kalman Filter (CDKF) is adopted to simultaneously estimate the longitudinal velocity, side slip angle and yaw rate of the vehicle and the equivalent lateral stiffness of the axle. In order to verify the performance of the strong tracking CDFK algorithm, typical cases using model-in-the-loop simulation systems are carried out. Simulation results show that the algorithm is effective and can get high accuracy.

An integrated parameter matching/energy management optimization method is proposed for active on-board Hybrid Energy Storage System (HESS). The optimization model with two indicators, HESS replacement costs and energy consumption, was set up and solved using controlled elitist NSGA-Ⅱalgorithm to obtain Pareto sets as alternatives. After comparing the initial cost, daily total cost and battery pack mileage of lifetime of the alternatives, HESS parameters and corresponding energy management were selected. When the daily range is within 48 km, the optimal battery pack capacity is 22 kW·h, when the daily range exceeds 48 km, the optimal battery pack capacity increases with the daily range. An ultracapacitor pack around 60 W·h is adequate for various daily range. Compared with the optimization results of battery only, using the proposed optimization method, the replacement cost is reduced by 11.5% in average, the battery pack mileage of lifetime is raised by 19.8% in average, the daily total cost is reduced by 13.2%. The proposed optimization method ensures that the main indicators are optimal and the secondary indicators are satisfactory.

A coordinated control system is developed for the regenerative and hydraulic braking systems in electric-wheel vehicle. The control system is based on real calculation of wheel slip ratio model to improve the stability of the electric-wheel vehicle in emergency braking process. Antilock braking control is realized by reducing the motor torque with setting a series of threshold values of slip ratio, which are compared with instantaneous longitudinal slip ratio calculated according to wheel speed, based on a redesign of hydraulic braking system. A 15 DOF vehicle model is established in AMESim and Anti-lock Braking System (ABS) control model is established in Simulink. Simulation is carried out at low, middle and high grade of adhesion coefficient of the road. Results show that the proposed control strategy can prevent the wheel from locking as efficient recovery of braking energy, and ensure the braking stability of the vehicle.

A braking hysteresis compensation system for commercial tractor-semitrailer was designed and analyzed. A test bench of the commercial tractor-semitrailer braking system was set up, and the braking hysteresis characteristics of the tractor-semitrailer was tested. According to the analysis results of the causes of the braking hysteresis of the tractor-semitrailer, a set of electronic controlled braking hysteresis compensation system was designed. The tests were carried out based on the hardware in the loop simulation platform under the typical working conditions. The results show that the braking hysteresis compensation system can shorten the braking hysteresis of the trailer effectively, and improve the overall performance of the tractor-semitrailer.

The model based control strategy plays a key role in the power coordinate control. The powers from the electrical and mechanical sources are deeply coupled, and the dynamics of the engine strongly affect the coordinate control. In this paper, sweep signals are used as excitation signals to obtain a frequency domain model set of a class of plants with uncertainties. After collecting data from identification test, the Chirp-z transform is adopted to calculate the discrete frequency spectra of input and output signals. Then, discrete frequency response is obtained. With little priori knowledge of the plant and the type of uncertainties, Laguerre orthogonal basis functions are chosen to construct the nominal frequency domain model. Furthermore, a model set of the plant is determined by using a genetic algorithm, which can depict model errors and some unknown uncertainties. The results are helpful for system analysis and controller design.

In order to solve the problem of blindness in the load development of automotive chassis component bench test, the block cycle load was converted to arm fatigue bench test after investigation of the rain-flow counting, duty cycle compiling and damage calculation of the collected road load spectrum on proving ground. The durability results of the virtual bench test and physical bench test of the control arm show that the damage distribution between the bench test and the proving ground is identical, which provides a new idea for the determination of the chassis structure bench test load. Besides, it can also accelerate the test period and decrease the test cost.

Currently climate wind tunnel lacks the information of ground simulation. To overcome this problem, based on numerical simulation, a 1∶1 scaled model of the climate wind tunnel and passenger car was created. Then, the ground effect on the vehicle cooling system experiment in climate wind tunnel was investigated. Results indicate that, the introduction of a single moving belt leads to the difference of the flow field distribution in the vehicle's underbody. The thickness of the ground boundary layer decreases and the underbody airflow velocity increases accordingly, which reduces the total pressure of the cooling airflow outlet, resulting in the mass airflow passing through the radiator increases by approximately 1.2%.

The relationship between the modifications of spot-welding mass matrices or rigidity matrices and Body in White (BIW) structural dynamic characteristics is investigated. First, the spot-welding parameters of shell structures in BIW are identified in order to describe the actual structural frequencies and vibration mode. Then, the method of Elastic-Plastic Beam with Parameter Identification (EPBPI) is employed to simulate spot-welding. Finally, the EPBPI method is compared with the universal method of elastic-plastic beam spot-welding in dynamic characteristic analysis, and it is applied to simulate of the dynamic characteristics of a real BIW to further validate the simulation accuracy. Results show that the EPBPI spot-welding simulation method can improve the accuracy of dynamic characteristic simulation of shell structure and provide a research method for spot-welding numerical simulation.

Under-segmentation and over-segmentation exist in the process of road segmentation for the environment system of intelligent vehicle. To solve such problem, a road segmentation method based on loopy belief propagation algorithm is proposed. First, multiple label Markov Random Field is applied to build grid map in the polar coordinate system, and several measurement cost function models are constructed based on the point distribution in each grid cell. Next, the local smoothness and slop hypothesis are integrated to establish smoothness cost function model and ensure the discontinuity of the ground height among the grids. Finally, the loopy belief propagation algorithm is employed to transmit the message repeatedly, and the road height of each grid is estimated with the largest belief to segment the road points. Experiment results show that the proposed method has better road segmentation performance than other methods, especially for rough or sloped road conditions.

In order to overcome the disadvantages of current insulation detection method, a new method is designed and realized with four relay switches and four 1% resistances in parallel respectively between positive or negative electrode of the power battery and the chassis; and a simple real-time battery insulation on-line monitoring system is developed. This method can effectively avoid the limitations of the current insulation detection method. The system was tested with SE40AHA lithium iron phosphate battery. The results show that the system can be used to monitor the insulation resistance during the power battery charging and discharging process and the insulation detection precision is within 3%.

In order to study the visual characteristics of the driver under stress condition, the eye movement data of drivers under different stress scenarios are analyzed. The dynamic clustering method is used to divide the gaze area, and the related visual characteristic indexes are selected to analyze. The principal component analysis and statistical analysis methods are used to analyze the eye movement data of the drivers. Test results show that when driver is under the stress scene the visual distribution is more concentrated, and the driver is more accustomed to obtain traffic information from the main area of the front region. When a moving object is in the scene, the driver will judge the moving range of the object and select 1 to 2 related auxiliary areas for information retrieval. The driver is used to gaze the main area and scan the auxiliary areas.

In order to directly reflect the traffic state at the roundabout, a model of vehicle travel time at roundabout was proposed based on vehicle lane choosing characteristics. The boundaries among the entering area, circling area and existing area at a roundabout are calibrated using the accumulative probability of the initial location of lane-changing. A relation model between the probability of lane choosing and traffic volume is developed with real field data. Considering the influences of the factors of roundabout geometry condition, vehicle queuing and lane changing, a travel time prediction model was established to obtain entering time, circling time and existing time. Finally, the model parameters were calibrated using survey data. Results show that the error of the prediction model is within 10% that meets the accuracy requirement. Thus, the model is beneficial for the traffic state evaluation and control method of the roundabout.

In order to improve the loss of traffic efficiency caused by the application of variable speed limit control, the integration of adaptive cruise control and variable speed limit control is analyzed to control the highway traffic. The cruise control model is developed from the intelligent driver model, and then it is integrated with the variable speed limit control method. The microscopic traffic data of the NGSIM in the USA are used to calibrate the models. Simulations of the highway traffic are carried out. Results show that the integrated control method reduces the average increasing rate of vehicles' travel time by successfully declining the speed of the vehicles in the upstream of the bottleneck, thus improving the traffic efficiency of the highway. The results of this study may provide valuable information for highway traffic management.

To explore effective approaches of intervention on road rage, a driving anger detection model based on driving behavior is proposed. The driving behavior data in angry and neutral states were acquired by conducting timed experiments for driving anger induction in busy traffic sections. Piecewise Linear Representation (PLR) method was used to fit multivariate time series, which consists of steering wheel angle and vehicle lateral position, and a bottom-up algorithm was implemented to separate the multivariate time series. The slope and time interval of each segment were extracted as the input features of a Support Vector Machine (SVM) model, which was used to recognize the driving anger. The validation results show that the accuracy of the proposed model with ten segments is 78.69%, which is 8.57% and 4.85% higher than that with five segments and twenty segments, respectively. This study may provide reference for the design of real driving anger detection devices based on driving behavior.

The principle of local maximum entropy is used to improve the lane-changing rule. Meanwhile, lane-changing with entropy-increasing probability is introduced, and the serial update method is used during the lane-changing. It reflects the electric bicycle flow characteristics very well. Then, the concept of lane-changing wave is introduced, and the formation mechanism and propagation of the lane-changing wave are analyzed, which is used to explain the relationships of lane-changing rate with the number of lanes and between the lane-changing with entropy-increasing probability. Furthermore, the influence on the fundamental diagram is analyzed under different parameter set in deterministic and stochastic cases. If the flow is appropriate, four lanes for electric bicycle lanes can more easily make the flow of metastable state appear in the high branches, and improve the using-efficiency of the road. Finally, field observations were carried out to calibrate the slowdown probabilities. The model is compared with multi-value model, dynamic floor model and field observation data. The results suggest that the proposed model not only overcomes the defect of the existing models, but also has higher accuracy.

To solve the problem of mechanical response behavior of track and subgrade, and the structure design of subgrade bed under overweight goods, an integrated model of track and subgrade was established. Based on soil elastic-plastic theory, the response laws of the track and subgrade under overweight good were analyzed. The mechanism of the spatio-temporal evolution of the mechanical properties were revealed, and the overall thickness of the track and subgrade was recommended under overweight goods. Results show that, the dynamic bending stress value imposed on the rail does not exceed the allowable value. The maximum pressure of the sleeper is 222.2 kN, which is close to the designed bearing capacity, 230 kN, of the cross-section of type Ⅲ sleeper. The bearing capacity of the ballast track structure does not satisfy the transportation requirement of overweight goods. Therefore, the subgrade bed must be adequately tamped and compacted before and after the trains pass the railway. The maximum dynamic stress at the top of the subgrage bed is 197.37 kPa, which is more than the critical dynamic stress, 169 kPa, of group A filler. The overall thickness of the track and subgrade should be 4.3 for overweight goods. The results of this work can provide theoretical basis and technical reference for the safe transportation of overweight goods and the maintenance of the track and subgrade.

A novel spatial grid model is proposed and applied to analyze the shear lag effect of six tower cable-stayed bridge. The theoretical principle of the proposed spatial grid model is elaborated along with the relevant illustrations of the modeling parameters of the composite box girder with corrugated steel webs. Then, the typical transverse and longitudinal shear lag coefficient distribution patterns at the key cross sections of side-span and mid-span are analyzed to provide reference for simple bridges. The effectiveness and accuracy of the proposed spatial grid analysis method is validated through cable-stayed bridge.

The coupling effects of the macro content and meso micro characteristics of mineral powder on the low-temperature performance of asphalt mortar were studied, and the macro content of the mineral powder was determined. The meso voids in unit mass of the mineral powder was measured based on the principle of Rigden void ratio. Based on the critical and fatigue damage control indicators, the optimum ratio of fixed asphalt to free asphalt in the asphalt mortar under different low-temperature conditions was determined, from which the optimum ratio of filler-asphalt can be obtained. Results show that the coupling of the macro content and meso micro characteristics of the mineral powder can be determined from the ratio of fixed asphalt to free asphalt. The results of this work are important for the improvement of the pavement performance of asphalt at low temperature.

In order to study the diffusion mechanism of grout in soil body collapsible loess area, a simulation analysis method of grout flowing diffusion in 2D surface is proposed based on fracture mechanics theory. The formation pattern of crack was described, the failure criterion and judgment method of the crack growth in fracture grouting were established, the problems of crack growth and coupling of seepage and stress were solved. Meanwhile, by setting up the crack growth equation with ABAQUS software, the fracture grouting pressure and the influence of physico-mechanical properties of soil body on the length of crack growth were analyzed. Results show that, to calculate the facture grouting pressure, crack growth length and the soil body strength parameters must be considered. In loess fracture grouting, fracture grouting can not obtained by continuous pressure, which should replaced by segmented pressure to ensure the aggregation of energy in crack growth process. Laboratory model experiments were carried out and the results are in good agreement with that of model analysis, verifying the proposed simulation analysis method.

Spray droplet size is one of the important parameters to evaluate the spray characteristics of injector, and is also one of the significant boundary conditions of the engine combustion system. In this paper, the spray droplet size characteristics of Gasoline Direct Injection (GDI) engine is studied using laser diffraction technique under the conditions, such as different spray pressure, injection pulse width and space position. The results demonstrate first, the big size droplet is prone to occur due to the unstable pressure difference between the inner and outer of the orifice at the beginning and end of spray; second, the influence of spray pressure and injection pulse width on the droplet size is a dynamics process, therefore, it is important to optimize the injector's parameters to obtain appropriate spray droplet size; third, spray droplet distribution in the space is not uniform and droplet size in the center field of the spray plume is bigger than that in the boundary field.

In order to solve the current problem that some printed pieces with cantilever and cavity structures but not allowed to add internal support can not be printed, a type of 3D printer with reversible working platform was designed. The structure composition and working principle were introduced. Through kinematic analysis of the system model, the kinematic positive and inverse solutions of the working platform mechanism were obtained, which provide the basis for the velocity analysis and motion control of the 3D printer mechanism. The simulation model was established using ANSYS simulation software, the stress and modal analysis of the structure of the working platform and the nozzle were obtained, which verify the feasibility of the design scheme. Consequently, the possibility that the working platform can be turned over was achieved and the non-support surface structure can be printed.

Based on full-size vehicle collision test, a new Finite Element Model (FEM) of dummy is built, and the corresponding parameter optimization method is proposed. To improve the consistency between the results of dummy simulation and full-size collision test, it is necessary to scientifically adjust the major structural material parameters of the FEM of dummy. First, the parameter optimization method is proposed and the important parameters, which significantly affect the simulation results, are selected. Then, the optimal method is applied to obtain the modified FEM of dummy that is similar to that of the full-size vehicle. Finally, taking the chest pressures of some FEMs of dummy in positive collision as examples, the main material parameters of the dummy chest are selected and the structural parameters are modified by the optimization method, thus, ensuring that the chest pressure peak and spring rate of the simulation dummy are consistent with the full-size vehicle collision results. The method proposed in this work can be used to improve the FEM of dummy to meet the requirement of full-size vehicle collision simulation.

A 6-DOF hybrid precision assembly platform was designed to assemble the optical and mechanical modules of the huge laser facility SG-III. Based on analytic method, the position and posture mapping relationship between the pose module and pose adjusting mechanism was established, and then the invert kinematics was obtained. By employing BP neural network, the nonlinear mapping model from driving displacements to the pose module positions and postures was built, and the forward kinematics was acquired by training the inverse kinematics samples. In order to improve the accuracy of the forward kinematics, the network was divided into six sub-networks corresponding of each DOF, thus, the accuracy of the solution was increased by one order of magnitude. Finally, position compensation algorithm was proposed to optimize the network. The results demonstrate the displacement accuracy is enhanced to level 10^-3 mm, which meets the requirement of engineering application. The reliability of the proposed methods is validated by simulation in MATLAB software, which can be applied to solve the forward and inverse kinematics of common hybrid robots.

In order to join aluminum alloy sheets effectively and reduce the protrusion height, a reshaping method was investigated in this paper. A clinched joint was produced by extensible dies, then the clinched joint was reshaped by a flat die and a bumped die. The shearing strengths of the clinched joint and reshaped joint were measured; the energy absorption, failure mode and relevant geometrical parameters were obtained. The results show that the reshaping method can not only reduce the protrusion height, but also increase the shearing strength and energy absorption. The neck thickness of the joint is increased by the reshaping method to increase the shearing strength.

In order to reasonably compute the average maintenance time of combination of CNC machine tools, a calculation method of the average maintenance time is developed based on the system component failure rate and maintenance time model. First, according to the subsystem fault information of the combination of CNC machine, the mean rank method is introduced to establish the time related subsystem failure rate model. Then the system failure rate model of the combination of CNC machine tools is derived. Finally, combining the subsystem maintenance time function, the average maintenance time model of the combination of CNC machine tools is established, and the average maintenance time is determined by the minimum number of failures. This research may provide reference for system maintenance time design and maintenance planning.

An experiment study on the flow characteristics of aluminum alloy 2B06 sheet under normal stress is carried out on the basis of the elliptical hydraulic bulging. The equivalent stress-strain curves of the target sheet are obtained by the ellipse bulging experiment with different ratio of the length semi-major to semi minor,b/a; meanwhile, the material and the thickness of the overlapping sheet are varied. The results show that, when nicking occurs, the equivalent stress-strain curve of the target sheet can achieve greater strain under the action of overlapping sheet. With the decrease in b/a, the flow stress curves tend move away from the curve obtained by circular (b/a=1) bulging test. At the same time, the larger strength coefficient of overlapping sheet, larger hardening exponent and larger thickness of the overlapping sheet lead the thickness of the target sheet more uniform. Proper overlapping sheet can significantly improve the flow characteristics of the target sheet.

Transient liquid phase diffusion bonding of steel/aluminum alloy dissimilar metal joints was carried out with pure Cu foil as the interlayer. The microstructure and mechanical properties of the joints were analyzed by Scanning Electron Microscope (SEM), Energy Dispersion Spectrometer (EDS), X-ray Diffraction (XRD) and instron testing machine. Results show that, under the bonding condition of 580 ℃ and 15 min, layered structure appears in the joint. With the increase in holding time and bonding temperature, the width of diffusion zone increases, which indicates that sufficient reaction occurs at the interface, and the layered structure can not be observed obviously. However, cracks appear in the Fe-Al intermetallic compound layer near the steel side. The microhardness of the Fe-Al intermetallic compound layer adjacent to the steel side reaches 439 HV. When the holding time and bonding temperature are 30 min and 580 ℃, the joint shear strength reaches the highest, up to 77 MPa. At the beginning of the joining process, Cu foil added generates eutectic liquid to wet the surface of steel and aluminum alloy and blocks the interdiffusion between Fe and Al elements in the later joining process. Thus the joint quality can be ensured.

Heat resistant bulk Al was prepared by mechanical milling, cold isostatic pressing and press-forming technique. The bulk Al possesses stable microstructure, with grain size between 0.6 and 4 μm, and the ultimate tensile strength, 536 MPa, surpasses that of most commercial Al alloys, especially at high temperature. The heat exposure experiment was carried out at 200 ℃, 300 ℃ and 350 ℃ for 4320 h. The high temperature endurance strength is 381 MPa, 242 MPa and 178 MPa corresponding to 200 ℃, 300 ℃ and 350 ℃ respectively. The pinning action of the second-phase dispersoids in bulk Al highly restrains grain growth during the process of hating.

In this paper, aluminum and Polymethylmethacrylate (PMMA) were used as experimental substrates, BOPP and RTV-1 WH-705 were used as two kinds of different elastic coatings, and the ice-adhesion strength on the coated substrate was measured with an Al-cup for ice making. The tangential ice-adhesion strength testing equipment was used to measure the ice-adhesion strength on uncoated and coated aluminum and PMMA substrates with the elastomeric coatings. Results show that elastic modulus of the coating has significant effect on the ice-adhesion strength on the substrates. Compared with uncoated substrates, the ice-adhesion strength on substrates coated with BOPP and RTV-1 WH-705 is decreased obviously. the ice-adhesion strength on aluminum substrate coated with elastic RTV-1 WH-705 is deduced by 73.27%, and that on PMMA substrate coated with elastic RTV-1 WH-705 is deduced by 14.85%. It is shown that the elastic coefficient and distribution of the coating have significant effects on the ice-adhesion strength. Thus rational choosing coatings and coating distribution on substrate can effectively improve the anti-icing an de-icing properties of the substrates.

The chemical synapse coupling synchronization of Hindmarsh-Rose neurons and the effect of Gauss white noise on the synchronization of coupled neurons were studied. It was found that the coupling strength can affect the discharge activity of the coupled neuron system and the synchronization between the coupled neurons. By adjusting the coupling strength between the coupled neuron systems, the two neuron systems can be changed into the synchronous state from the non-synchronous state. At the same time, it was also found that the appropriate noise can induce the synchronization behavior of the non-synchronous Hindmarsh-Rose neurons, which can cause the synchronization of the chemical synapses.

A recursive robust filtering method based on the orthogonal projection and an innovation analysis approach is proposed for stochastic uncertain systems with delayed measurements. First, the original system is transformed into a stochastic uncertain system with correlated measurement noises, and the innovations are recalculated. Then, by applying the mathematical induction, the newly obtained innovations are proofed to be uncorrelated with each other. Finally, the desired recursive robust filter is designed via an innovation analysis approach and the orthogonal projection theorem. Without resorting to state augmentation, the proposed filter treats the noise correlated across time directly. Therefore, the desired filter has less computational burden, but a high computational accuracy. Simulation results demonstrate the effectiveness of the proposed approach.

For the phenomenon that the position of cable bundle in reality is non-deterministic geometric, this paper proposes the statistical analysis method of cable bundle crosstalk model based on Polynomial Chaos Expansion. The orthogonal polynomial basis functions are chosen based on the distribution pattern of the variables related to the positions of wires in the cable bundle, and the distributed parameters of the wires can be expressed by the Polynomial Chaos Expansion. With the boundary conditions, the extended MTL can be solved by the modeling methodology, and then the voltage vector and current vector can be expressed by the Polynomial Chaos Expansion. According to the properties of the Polynomial Chaos Expansion, the mean, standard deviation and variation range of the cable bundle crosstalk can be obtained, and the probability density function of the cable bundle crosstalk can also becalculatedthrough numerical method. Thus, the efficient prediction of electromagnetic compatibility of cable bundle in complex system has realized.

An ant colony algorithm with features of high robustness, distributed computing, and positive feedback, is used to solve edge detection problem. In order to prevent extracting discontinuous edges and missing weak edges by using ant colony algorithm, some improving measures are put forward. An Ostsu's method for pre-processing is proposed, the initialization of pheromones matrix and heuristic matrix is improved; meanwhile, pheromones asynchronous update strategy and parameter self-adaptive modification are applied to avoid early stagnancy. Experiments show that the proposed method can extract more continuous edges and weak edges with better robustness.

In this paper, a geometric constraint system is represented by a bipartite graph model, which expresses geometric primitive parameters and basic geometric constraints, and a new Geometric Constraint Solving (GCS) method based on the maximum matching of bipartite graph is proposed. The under- and over-constrained sub-domains are identified by using the bipartite graph decomposition method. An under-constrained sub-domain is processed by introducing the geometric constraint priority and improving the geometric constraint assembly mechanism. The consistent and inconsistent over-constraints are identified by the modified artificial bee colony algorithm, and the identified over-constrained sub-domain is also effectively processed. Research results show that the GCS method based on the new bipartite graph model is effective.

Considering the characteristics of medical images, a multi-scale region growing segmentation algorithm is proposed. First, the original image is smoothed by a Gaussian filter. Then, the region growing segmentation is performed on both the original image and the smoothed image. Finally, the two obtained segmentation maps are compared to get the final segmentation. In the process of region growing segmentation, a pixel in the background region is selected as the initial seed for region growing. The advantages of the proposed algorithm are the robustness to noises and easiness of initial seed selection. This method is also suitable to other segmentation applications, in which background region is simple but target region is complex. In order to select an appropriate threshold, the concept of Maximum Gradient Transform (MGT) is proposed. The issue of threshold selection is converted into a minimization problem with the assistance of the statistical properties of the transformation matrix. Experiment results show that the proposed algorithm can obtain accurate medical image segmentation results.

To meet the real-time requirement in complex human-computer interaction, a Single Instruction, Multiple Data (SIMD) parallel collision detection algorithm based on optimization operator is proposed. By introduction of optimization operator, the search space is confined in a non-uniform local minimum area, reducing the colony search time. In the process of solving the multiple ant colony, the load balancing strategy is used to assign the sub-tasks to each processing core on multi-core processors for parallel execution. Results show that, compared with the classic I-COLLIDE, MPI and Pipelining algorithms, the proposed algorithm has better performance in solving the human-computer interaction in collision detection.

A clustering method for uncertain data based on spectral decomposition was proposed. The method was applied to explore the true covariance structure of data records behind the uncertain representation under the natural potential association of the data. The data analysis method based on spectral decomposition can get the sharpening data according to the covariance structure. Then, clustering analysis of the sharpening data is carried out. The comparison experiment results show that, using the proposed method, the clustering quality improves significantly; the results of root mean square error and CH index are all better than that obtained using the traditional method.

An actual point to point Quantum Key Distribution (QKD) experimental system of polarization encoding was built based on BB84 protocol under stress testing conditions. QKD experiment under commercial fiber channel stress was carried out. The main parameters of the system were collected in real time for data analysis. The results show that, with the increase in the external forces on the fiber channel, both the decoy state error rate and the signal state error rate of the QKD system increase, but the bit generation rate decreases. The tensile limit value of the QKD system is lass than the limit value of the pressure, the system is more sensitive to tension change. Results of this study may provide guidance for the application of key distribution in military and commercial secret communication.

High sensitivity acquisition architecture for Galileo E1 signal is proposed. This architecture processes E1B/C signals by time-division multiplexing, and then joins the results together. Compared with individual E1B or E1C channel acquisition, higher detection probability is achieved without the increase in hardware burden. In addition, a novel decision strategy, named threshold combining code phase, is also proposed. The strategy utilizes threshold and the code phase correlation of correct cell between multiple Intermediate Frequency (IF) data replays with different starting point of each replay. Compared with traditional threshold decision strategy based constant false alarm rate, the proposed strategy enhances the detection probability. When overall false probability is 0.002 and Carrier to Noise Ratio (CNR) downs to 27 dBHz, the number of acquisition rounds is 2, and the top 10 maximum values are retained in each round, the overall detection probability of the decision strategy is near 40%, while the overall detection probability of the traditional threshold decision strategy is less than 10%.

Tow-point Non-uniformity Correction (NUC) based on blackbody is not suitable to correct actual sky background. To overcome this problem, a new two-point correction method based on gradient sky background was proposed. First, the fixed positions of bind pixels are replaced by the pixels in neighborhood. Then, the two-point images are captured at two different pitch angles in the pure sky by infrared focal plane array detector; and gain and offset coefficients are obtained from two-point correction. Finally, the two correction coefficients are modified to remove a few remaining bas points. Results show that this method has good performance. In the second place, a new bilateral filtering and gradient template algorithm is proposed to detect dim point target after correction. First, median filter is used to remove remaining single noise. Then, convolution with the gradient template is made. Dim point target can be detected after adjusting image grayscale to the certain threshold interval. Results show that the proposed gradient template algorithm has advantages to suppress complex background. It improves Signal-to-noise Ratio (SNR), and has the preference of low complexity and easy implementation in real-time system.

Based on Field Programmable Gate Array (FPGA), two sets of CameraLink interface transfer hardware platform are designed to compare serial-parallel converter chip and CameraLink interface based on FPGA). A new method, in which on-chip debugging tool Chipscope is combined with synchronized generation module, is proposed to detect error data accurately. The results show that CameraLink interface based on FPGA uses fewer pins with higher speed transmission rates. Single port supports a maximum transfer rate of 4.31 Gbit/s when the pixel clock is 154 MHz. The CameraLink data output can drive 6 m CameraLink transmission line, with no bit error appears for long hours, and it can be used in a variety of different systems based on CameraLink interface.

To overcome the redundant feature descpriptor, high computational complexity, low matching precision when the angle of rotation or view spends greatly in image registration method based on SURF algorithm, an improved SURF algorithm is proposed. First, the feature points are extracted using Hessian matrix. Then, the feature descriptor for each keypoint in the circular neighborhood is constructed using Haar wavelet response; meanwhile, the normalized gray values difference and second-order gradient of this region are computed. Finally, RANSAC algorithm is applied to eliminate false matches. This method not only performs faster than SURF algorithm, but also fully employs the image gray information and details to acquire higher accuracy. Results indicate that the proposed method has strong robustness and stability for blur, illumination difference, angle rotation and viewpoint change. A well-edge mosaic image is obtained without obvious geometric misalignment in the remote sensing image mosaicking process. This method is an effective image registration algorithm with high-speed and precision, and it satisfies the need of registration in the remote sensing image mosaic.

In this paper, an image encryption algorithm based on two-dimensional, two state and five neighbor reversible Cellular Automaton (CA) is proposed. First, this method is applied to analyze several X type neighbor structures of CA, and a partial X type structure of CA is put forwarded, which has obvious key confounding effect. Second, in each CA encryption iteration, the results are processed with matrix transpose operation; then the key image with one-dimensional four neighbor CA is generated, which has chaotic behavior at the rules of 9d62 (hex). Finally, the key information is put into the CA boundary conditions, so that the key is involved in each cellular automaton iteration. Experimental results show that using partial X2 type CA structure and new model of key design can improve the sensitivity of the key in the encryption system. Compared with traditional single XOR operation, the new method can also reduce the number of CA iterations, thus, possessing advantages in plaintext diffusion rate and obfuscation key, the diffusion rate is increased by 36.14%.

The raw echo generation model is established considering the varying target electromagnetic scattering characteristics, and the module effects on azimuth and range direction are also presented. The echo generation and imaging results for typical target demonstrate the effectiveness of the proposed analysis method. Further improvement direction is put forward for the high resolution spaceborne SAR image simulation.