In order to achieve the lubrication of water bearing in high-speed tire test rig under high slip, hydroplaning mechanism is applied in this test rig. A line contact Elastohydrodynamic Lubrication (EHL) model is established, which includes Reynolds equation, thickness equation and deformation equation. The thickness of the water film at the contact interface and the pressure distribution are obtained from the results of numerical iteration calculation. The relationship between the critical speed and tire pressure is analyzed. A water film is formed as the hydrostatic water bearing speed is below a critical value. Compared with NASA formula of hydroplaning critical speed, the high-speed tire test rig can form a dynamic lubrication water film at a lower speed.

A multi-objective integrated vehicle dynamics control algorithm is proposed for electric vehicle with x-by-wire actuators. This algorithm mainly uses feedforward control takes the feedbackward control as the supplement. The integrated control structure is established and the intention interpret layer, control command layer, control allocation layer and actuator layer are designed separately. A new type of rapid prototype test bench is built up using two both DS1103 single-board and DS1006-based mid-size dSPACE real time simulators. Tests are conducted on the test bench under typical working conditions. Results show that the proposed control method can enhance the control performance of the vehicle. The developed rapid control prototype testing method is easy and flexible, which can effectively shorten the development cycle and improve the development efficiency for vehicle control system design.

The pressure characteristic of vehicle brake system is a key factor influencing the braking performance. The structure and working principle of an electronic hydraulic brake system are introduced. Aiming at the dynamic response characteristics of the system, test trails of increasing pressure, reducing pressure and maintaining pressure are conducted in typical conditions. The trails are conducted on a developed test bench with data acquisition control system, and the test program is written and embedded into the electronic control unit in Codewarrior development environment. Form these trials the brake system pressure variation characteristic in typical operating conditions is acquired. Test results show that the dynamic response and controllability of pressure are favorable, and could be applied in vehicle chassis integrated control system. This study may provide important reference for further theoretical research, development of control strategy and the real vehicle test.

In order to solve the issue of frequent mode-switch of hybrid electric vehicle, a new scheme is proposed. The scheme integrates the time based, filter based and fuzzy logical and hysteresis based methods. Simulation results show that adopting the proposed scheme the percentage of mode duration less than 4 s is reduced from 85% to 3%, which mean that the number of mode switching falls nearly 80%. Meanwhile, the actual vehicle velocity follows the desired velocity and the charge maintains within a narrow operating band as well. The maximum and average impact equivalent degrees are reduced by 42% and 61.4%, and the fuel economy of the vehicle is improved by 9.4%.

A novel pure electric vehicle with dual motors configuration is introduced. The energy conservation potential and mechanism of this new vehicle are analyzed. First, the structural characteristics and operating mode are investigated. Then the parameters of the powertrain and control strategy are designed. The rationality of the parameters and the validity of the control strategy are demonstrated in MATYLAB/Simulink. As compared to the traditional pure electric vehicle, the energy conservation potential of the new pure electric vehicle with dual motors is around 10%.

This paper studies the lightweight design method of the twist beam of rear suspension of a domestic passenger car. The whole vehicle's rigid-flexible coupling model with flexible twist beam was built using multi-body dynamics software. Modal test of the twist beam in a free-free configuration and vehicle road test of ride comfort were carried out to verify the validity of the proposed model. On this basis, the modal displacement time history of the twist beam was calculated from a dynamic simulation on the durability enhancement road. Then the stress time history of the twist beam was obtained based on Modal Stress Recovery (MSR). According to the nominal stress method, fatigue life of the twist beam was assessed. Furthermore, mesh morphing technology was employed to build the parametric model of the twist beam, which was used to define the design variables. Then, the Kriging approximation model and particle swarm algorithm were adopted to perform the multi-objective optimization of the twist beam. The mass and fatigue life were defined as the objective functions, while the first modal frequency and torsional stiffness were taken as the constraints. The Pareto optimal set was found and one of the optimal solutions was chosen to check the effectiveness of the optimization method. The results indicate that the weight of the optimized twist beam is reduced 20.35% while its fatigue life satisfies the design requirement.

In this paper three psychoacoustic parameters, loudness, sharpness and roughness, are introduced to evaluate the abnormal noise for commercial vehicle cab. The noise transfer and acoustics distribution characters of the vehicle are investigated and analyzed by means of field measurements and virtual simulation based on subjective evaluation of sound quality and frequency characteristics analysis. Identification of the abnormal cab noise is made to find a control method. The results show that the abnormal noise for commercial vehicle cab occurs at the vehicle speed of 70 km/h. the sound quality of the vehicle cab is mainly affected at the frequency ranges of 22-36 Hz and 56-90 Hz. The main reasons are the higher structure excitation near frequency 25 Hz, and the resonance coupling of the cab structure and cavity at 58 Hz by the exterior vibration and noise transfer characters, respectively. At low frequency, the interior sound pressure distribution is higher in the underside and lower in the middle at the cross-section. The loudness distribution is also higher in the underside, but not lower in the middle at the cross-section at 0-1 Bark.

In order to improve the thermal environment of the loader engine cabin and the heat transfer performance of the radiators to ensure the stable vehicle performance, a 3-D physical model of the loader was built. Virtual wind tunnel and numerical simulation were used to predict the influence of the exhaust system on the cabin thermal environment and radiator performance. The heat transfer power of the radiators was compared under two kinds of exhaust system. Analysis results show reasonable agreement with experiment results, which proves the accuracy of the model. Simulation results show that using insulated exhaust system could significantly reduce the air temperature in the engine cabin. The thermal environment of the engine cabin was improved. The heat transfer performances of the hydraulic oil radiator, the water radiator and the transmission oil radiator ware increased by 9.0%, 7.3% and 6.8%, respectively. The results of this work may provide guidance for vehicle thermal management of the loader.

Contingent Valuation Method (CVM), one of the most widely used methods to estimate non-market goods, was introduced to quantify the crowding costs in bus, which is an important part of the total costs of bus trip. With the goal of utility maximization, the relationship between the crowding costs and Value of Time (VOT) was deduced from the concept of willingness to pay. To further establish the model of the crowding costs and load factors, the relationship between VOT and load factors was analyzed and improved based on the existing models. Meanwhile, in accordance with the questionnaire data in Hangzhou city, the relevant parameters were obtained using the binary Probit model. Then, the crowding costs were quantified under different crowding conditions. The results show that the crowding costs are nonlinear, when the load factor is greater than 2.0 the crowding cost is one third of the total costs of bus trip.

The capacity is a key parameter in bicycle path planning, design and management. With the rapid development of electric bicycles (E-bikes) in China, the E-bikes and the bicycles share the conventional bicycle path, which leads to certain safety and efficiency issues. Five classic speed-density relationship models were introduced to build the speed-density relationship of mixed bicycle traffic flow. The bicycle path capacity was estimated using the flow-density relationship. Field data were collected from three bicycle paths in Hangzhou, China for calibration and validation. With 61% of E-bikes, the mean capacity of per meter width of the three paths is 2000 bicycles/h. Finally, the effects of riders' gender, age and E-bike proportion were analyzed. Results show that riders' gender and age have no significant influence on the path capacity, while there is significant linear correlation between E-bike proportion and bicycle path capacity.

In order to directly reflect the degree of congestion at roundabout, a model of vehicle travel time at roundabout was propose based on Origin-Destination (OD) distribution. First for the particularity of roundabout, a relationship model between roundabout geometric dimension and the vehicle travel time under noninterference state was established applying geometric knowledge. Second, probabilistic statistical methods were used to analyze the vehicle's characteristics of lane choosing at roundabout, and a vehicle lane change model was established under specific OD, thus to obtain the vehicle delay caused by lane changing. Third, by analyzing the actual survey data and the relationship between flow rate at weaving section and waiting time, a waiting time model of vehicle at the entrance of weaving area was built. Finally, the model parameters were calibrated and the model was validated using survey data. Results show that the prediction error of the proposed model was within 10% that meets the accuracy requirement.

Traditional metering signalization is designed for individual entry at roundabout with unbalanced vehicular demands, which could fail to avoid circulatory roadway from locking up. A new control strategy of full metering signalization at roundabout is proposed which can be used for multilane roundabout. Traffic detectors are placed on each approach and the circulatory roadway to detect time headways and occupancy times. Metering signals are installed on each approach and are used on a part-time basis. Metering signal operations can be managed in three modes. Four function modules driven by traffic events are designed to avoid circulatory roadway from locking up. These modules satisfy different levels of vehicular demands by dynamically changing the mode of metering signal operation and the durations of different color signals. VISSIM simulation results show that good performance of proposed full metering signalization is obtained in low and medium load demand scenarios. The poor performance in heavy load demand scenarios indicates the necessity to implement full signalization on every approach and on the circulatory roadway.

In order to estimate the real-time queue length at signalized intersection, a macroscopic traffic flow model METANET was improved to describe vehicle accumulation and discharge process in urban road. First, the queue tail cell is identified according to analysis of the density calculated with the improved traffic flow model. Then, the vehicle spatial distribution in the queue tail cell is analyzed to identify the location of the queue tail, so that the queue length can be calculated. Finally, the proposed model is evaluated and the results demonstrate that this model can be used to estimate queue length in real-time with satisfactory accuracy. The proposed estimation method may be used to support the strategy generation of traffic control and management.

A dynamic Origin-Destination (O-D) matrix model based on least square approach is proposed for urban rail transit using moving-average strategy. Statistic analysis of historic automatic fare collection records shows that, in continuous periods, there is a strong average O-D flow relevance between priori passenger flow and current passenger flow. Therefore, a dynamic O-D matrix estimation model is established based on moving-average strategy. This model can utilize the priori flow information more efficiently. A passenger flow arrival coefficient based on the distribution of O-D travel time is defined to characterize the dynamics of traffic flow, thus establishing the relationship between O-D flow and in-and-out flow at stations. Finally, a case analysis of Beijing rail transit network is carried out. Results show that, comparing with existing model, the accuracy of the proposed model is improved about 15%~20% from the viewpoint of average relative deviation in a day. The proposed model can improve the accuracy of dynamic O-D matrix estimation in short time range for urban rail transit greatly.

In order to solve the problems of fuzziness and randomness in the division of congestion state in metro transfer hub, an identification method of pedestrian crowding degree factor is proposed based on normal cloud model. First, the connotation and the measure standard of the pedestrian crowding degree are analyzed, and according to their boundary value under different service level the digital characteristics of the cloud are calculated. Second, the cloud synthesis theory is applied to establish the template cloud corresponding to different service levels, and the survey data (pedestrian speed, flow etc.) are input into the cloud generator in order to set up the identification cloud model. Third, according the definition of cloud similarity, the similarity between the identified cloud and the template cloud in the infrastructure (e.g. channel, stairs) is calculated. Moreover, the crowding degree is defined independently, which is described in a quantificational level under the state of crowding degree in the metro transfer hub, and the method to identify the pedestrian crowding degree is given. The method is verified by a case study in a metro transfer hub in Xi'an. Results show that the pedestrian crowding degree in the channel 100.095, which is in the crowding state, the pedestrian crowding degree in the stair is 100.273, which is also in the crowded state. This method can not only accurately identify the crowded state quantificationally, but also reflect the change process of pedestrian crowding degree, which has strong practicality.

A survey of comprehensive transportation mixed network design and freight flow allocation was carried out. An optimal model was developed to minimize the total transportation cost and reconstruction cost, considering the investment budget constraint. A hybrid heuristic algorithm based on cloud harmony search strategy (C-HS) and ILOG Cplex optimization studio was designed to solve the model. The C-HS was used to optimize the reconstruction decision of the transport arc in the network, while the freight flow allocation result for harmony evaluation was solved by ILOG Cplex based on the k shortest path of the freight. The cloud model was used to enhance the harmony search convergence rate when the new harmony (new solution) was constructed. A numerical example was given and results show that the model and algorithm are effective.

Dynamic and static scenarios of overtaking on freeway were embedded into a driving simulator. Thirty drivers completed driving simulation and their saccade frequency, duration, angle and angular velocity were obtained. The driver's visual area was divided into five regions and the probability of viewpoint transition between any two regions was calculated. The results indicate that destination vehicle speed does not influence the saccade frequency, but shows positive correlation with saccade duration, saccade angle and saccade angular velocity. While the destination vehicle speed is the same, when overtaking a truck the driver's saccade duration is longer, saccade angle is bigger, saccade frequency and angular velocity are lower than that overtaking a small car. The driver's viewpoint transition frequency between initial lane and destination lane is the highest and the driver pays the most attention to these two lanes.

To improve the spraying quality of vehicle-mounted sprayer for liquid deicing and snow-melting agent, the influences of the fluctuations of the vehicle speed and the agent pump speed on the spraying quality are discussed. A pump speed control system is proposed under the condition of varying vehicle speed with the help of theoretical analysis and field test. Experiment results show that, when the vehicle speed is slower than a critical value, the pump speed maintains the threshold and the actual spraying volume deviates from the target value, but there is no striped spraying defect. If the vehicle speed exceeds the critical value, the pump speed would be automatically adjusted by the control system according to the vehicle speed and the actual spraying volume is close to the target value.

The reliability of the pavement structure under Freeze-Thaw (F-T) cycles is studied based on simulation test, in which various uncertainties of influence factors are taken into account. The impact of F-T cycles in Qinghai-Tibet cold region is simulated by F-T cycle test, and the reliability function of the asphalt pavement structure is built. Monte Carlo simulation method is employed to solve the reliability function. Analytical results show that the resilient modulus of asphalt concrete mixture declines under F-T cycles, the mixture performance decreases sharply in the initial F-T cycles and turns to gentle after 8 to 10 F-T cycles. The F-T cycle has significant impact on the reliability of the pavement structure, which decreases as F-T cycles increase. The reliability of the pavement structure also decreases as the coefficient of variance increases. An analysis method of the reliability of pavement structure under F-T cycles is proposed, which is useful to reflect the actual impact of F-T cycles on pavement performance in cold region.

The particle size distribution characteristics in a common-rail diesel engine with and without catalyzed Diesel Particulate Filter (DPF) under different fuels and operation conditions were studied by experiments. The filtration efficiency of catalyzed DPF for different particle sizes was analyzed. Results show that the exhausted particle concentration distribution curve presents bimodal structure when burning BTL and petroleum diesel with and without DPF. The DPF filtration efficiency is related to engine operation conditions and particle size distribution characteristics that the trapping effect is better for nucleation mode and ultrafine particles. DPF filtration efficiency for ultrafine particles can reach 75% under medium and low loads. As the speed and load increase the efficiency gradually decreases for different modal particles, and as the particle size decreases the efficiency increases. Compared with burning petroleum diesel, the exhausted particles are mainly in nucleation mode when burning BTL. BTL has higher filtration efficiency than petroleum diesel, especially under heavy load condition.

The elastic moduli of bulk materials were determined by means of four-point bending test on a self-developed small size four-point bending device. Using a displacement sensor, the method can automatically measure the displacement of the inner support rather than the mild-span of the specimen during loading process. After the calibration of the frame compliance of the device, the elastic moduli of machinable glass ceramic, 6061 Al alloy, c11000 Cu alloy and K9 optical glass were measured using the proposed method and the results coincide with the standard values of the materials. The proposed four-point bending test method is simple and can be used to measure the elastic moduli of bulk materials.

To meet the requirement of synchronization signals of multifunction electromagnetic instruments, a synchronization system is developed. The PC of the instrument is taken as the master device to design the interactive interface using LabVIEW programming. The parameters are set for the FPGA frequency division based on the acquired information of GPS Module and the idea of circular-queue. The hardware description language VHDL is used to design the FPGA modules to achieve the least square estimation of 1PPS and 10 kHz. The treated 1PPS is taken as the clock signal to control the FPGA frequency division module, and the module is applied to divide the treated 10 kHz for the generation of synchronization signal according to the parameters. Experiment results show that the developed system can manually or automatically generate 1 Hz to 5 Hz sync signals, with sync accuracy better than 0.03 s that meets the accuracy requirement of most electromagnetic methods.

In order to solve the overheating problem in the hydraulic system of loader working in summer, the lumped parameter method is introduced to study the heat transfer in the hydraulic system. A RC network of heat transfer model is established using the lumped parameter method, and the computational program is developed. The heat transfer in the hydraulic system of a 50 type wheel loader is simulated, and the simulating results are compared with test data. Results show that the simulation precision can satisfy engineering demand and the accuracy of the model can meet the needs of engineering design. This study provides valuable reference to the design and improvement of the hydraulic system of loader.

It is hard to measure the load history of the working device of hydraulic excavator in fatigue analysis. To solve this problem a novel fatigue analysis method is proposed. First, the complete change process of digging resistance, named Digging Resistance Load Spectrum (DRLS), is obtained by simulating the digging process of soil with the bucket of hydraulic excavator. Second, according to the DRLS, the load history of each hinge of the working device is calculated by the operation simulation of a full typical working cycle of the excavator. The simulation results are then verified by comparing with the actual cylinder pressure measured from the experiment similar to the working condition in the simulation. Finally, the fatigue analysis of the boom and arm of the working device are accomplished with the verified load histories of the hinges. The effectiveness of the proposed method is demonstrated with the fatigue analysis process of the working device of a 23 t hydraulic backhoe excavator. The results come out that the minimum lives of the boom and arm are 10^5.978 and 10^6.47 cycles respectively.

Soil sample with physical and mechanical properties similar to real lunar soil is prepared as the drilling object. The power consumption model of coring driller is proposed and verified by coring experiments. The lower power consumption drilling procedure is obtained by analyzing the power consumption curve. To ensure high cording rate, lower rotary speed can decrease the drilling power consumption in the allowable range of resistance moment of drilling. The data calculated from the proposed model is in good agreement with the drilling experiment results. Thus, the proposed model can be used to predict the drilling power consumption.

The surface feature of Mars, the chemical components, mechanical properties, grain sizes and their distribution of Martian regolith are introduced based the success of rover missions on Mars. The mechanical properties of some simulant Martian regolith used in the world are compared and analyzed. Then, three grain size distributions of simulant Martian regolith are proposed and the terra-mechanics characters, such as cohesion and internal friction angle, are measured. Results show that the cohesion ranges from 0 to 0.316 kPa and the internal friction angle ranges from 38.4° to 46.1°.

With the growing requirement of high reliability of the intershaft bearing of aircraft-engine, the fundamental research of this kind of product life is needed. A test rig has been developed to simulate behavior of this kind inner shat bearing. The test rig has the functional features of automatic controls of oil temperature, rotational rate and load, and automatic alarming. The structure and functions of the test rig are introduced, and its high-speed performance is tested. Results show that the test rig can meet the requirements to test the performance of the intershaft bearing of aircraft-engine working in real and complex conditions, the test process can be automatically controlled, the procedure parameters can monitored and stored in real-time. This test rig can be used as a basic testing platform of inner shat bearing of aircraft.

The domestic and abroad thermal vacuum quasi-accelerated life tests of two-axis gimbals are investigated. It is shown that almost all the tests are focused on the parts rather than on a full gimbal, which can not reflect the performance of the full gimbal. According to the analysis of the structure and lubrication mode of the thermal vacuum quasi-accelerated life tests of two-axis gimbals, the five main elements and their design methods are determined. The test contents and methods are designed for the motion performance examination of a full gimbal, and the failure criterion is given to control the test process. A thermal vacuum quasi-accelerated life test is designed in accordance with the design method of the element design method. A series of test data about the motion performance of the two-axis gimbal is acquired by experiments, which can evaluate the in-orbit life of the space two-axis gimbal. The in-orbit application of the obtained results demonstrate that the designed thermal vacuum quasi-accelerated life test method for the space two-axis gimbal can satisfy the test requirement and it is effective and feasible.

The influence of starting microstructure on the austenite grain refining potency in Electro-Pulsing (EP) was investigated by microstructure observation and hardness testing. Results indicate that the mechanism of austenite formation from the starting tempered martensite during Electro-Pulsing Treatment (EPT) is occurred by the α + Fe₃C → γ diffusional transformation, and austenite grains are ultra-refined (d_γ < 5 μm). This verifies the analysis that the austenite nucleation rate can be increased by EPT. However, the reverse transformation from martensite during EPT occurs by the α'→ γ displacive transformation process. The prior austenite grain boundaries of the starting martensite are not changed during the reverse transformation, leading to the formation of coarse grained Displacive Reverse Austenite (DRA). Martensite transformed from DRA after quenching is strengthened. As the peak temperature is increased during EPT, the recrystallization of DRA is occurred. The nucleation recrystallization is started at the boundaries of DRA, where the high angle microstructure is only reversed after displacive reverse transformation. The mean size of the austenite grains is 11 μm after recrystallization.

A finite element model of stretch forming was established based on distributed displacement loading and the displacement loading trajectory of forming the three-dimensional surface was designed. Spherical parts and saddle parts were selected for simulation, the effects of the number of discrete loading points and loading time-steps on the stress and strain distribution on the formed part were analyzed comparatively. Results show that the more discrete loading points, the higher uniformity of the strain distribution and the better forming quality; and the more loading time-steps, the smaller variation of the stress magnitude and the better forming quality. However, when the loading time-step reaches a certain value, there were no obvious changes in the stress and strain distributions with further increase in the loading time-step. Experiment results demonstrate to feasibility of proposed displacement loading method.

In the forming process of heads the defects of wrinkling, swelling, nonuniformity of the thickness, and springback deformation occurred in a certain factory. To solve these problems, optimized scheme is proposed. The objectives of this scheme are reducing the swelling, enlarging the region of uniform thickness, and decreasing the springback deformation. The optimizing factors include the clearance between the punch and die, the matrix radius, the height of drawbead and the relative position of the drawbead. The combination of software of Matlab and Design-Expert was adopted to conduct fitting and modeling analysis of the Response Surface Model (RSM). A second-order RSM with three objective values was obtained. The accuracy of the obtained RSM was verified and the error margin was less than 7.4%, which was available for subsequent optimizations. The actual production results show that heads with good surface finish, small shape error and high dimension precision can be produced by the application of the proposed multi-objective optimization scheme of forming process.

To solve the kinematic optimization problem of the 7R humanoid arm, the closed-form solutions to the inverse kinematics based on the arm angle parameter were established. The range of the feasible arm angle corresponding to joint limits was determined using analytical methods. Besides, a new function was defined, which is used to evaluate the joint angles, and the optimal indexes of joint limits avoidance were transformed into virtual torques. Based on this, the self-optimizing method was proposed to solve the kinematic optimization problem of joint limits avoidance. Simulations demonstrate that the proposed method can determine the feasible range of the arm angle accurately and implement the kinematic optimization of the humanoid arm efficiently.

In order to enhance the output force of Ionic Polymer Metal Composites (IPMC), a novel linear actuator unit was designed. First the method of chemical deposition was used to prepare IPMC materials. Then the surface segmentation method was applied to fabricate the linear actuator unit model. The evaluation technique of fatigue peeling was proposed, and the crispation phenomenon of cantilever beam driving was analyzed. The performance of the linear actuator unit under square wave voltage was researched using an IPMC experiment platform. Results show that the crispation phenomenon can be reduced by controlling the voltage lower than 4 V, and the length to width aspect ratio smaller than 3.5. The output force along the motion direction first increases then decreases as the voltage increases, and the maximum output force is 2.15×10^-2 N when the voltage is 4 V, which is four times of the output ability of the cantilever beam. The output displacement keeps constant the does not change with the voltage. Furthermore, the output force along vertical motion direction also does not change with the voltage, which corresponds to the output ability of the cantilever beam. The output displacement also first increases then decreases as the voltage increases, and the maximum output displacement is 41 mm when the voltage is 4 V. The fatigue peeling analysis verifies that the optimal performance of the linear actuator unit is obtained when the voltage ranges from 3 V to 4 V.

A CSN-2 compression algorithm for integer data was proposed and applied to the compression of any documents. Moreover, the CSN-2 data compression algorithm does not need additional data support. A CSNE-2 decompression algorithm, which can properly restore the original data, was proposed by studying the CNS-2 decompression algorithm. It was proved that the results of the decompression algorithm are unique and correct in theoretical and experimental tests. Furthermore, it was demonstrated that the CSN-2 compression algorithm for the integer type of documents has a higher compression ratio, and could compress any documents compared with experiments of other compression programs.

Considering that the traditional programming language fails to use multicore processors to calculate conveniently and effectively, a parallel programming language is proposed and its core semantics and the relative algorithms of its runtime environment are defined. This language with Pi-calculus as its theoretical foundation first defines the core syntactic structure of the language based on the basic structure of Pi-calculus, and then defines the core operating semantics on the basis of synchronous communication in Pi-calculus process. This paper also defines the context of process in parallel operating semantics and designs the main data structure, which consists of overall architecture in operating and scheduling algorithms based on synchronous communication and garbage collection algorithm based on reference count. Therefore, the proposed parallel programming language is capable of using multicore processors to calculate sources easily and effectively.

In order to the convenient use of laboratory self-assembled Laser-Induced Breakdown Spectroscopy (LIBS), a software is designed and implemented. The system includes two parts: the control software and spectrum analysis software, and it possesses the functions of self-inspection, data acquisition, preprocessing and recognition. Model-View-Controller (MVC) is employed to design the system architecture, the design process of each model is described, and C# language is used to develop the software. Experiments show that the software can feasibly operate the LIBS to achieve spectral acquisition and qualitative analysis.

Kernel-based Fuzzy C-means Clustering Method (KFCM) is a common method for data clustering. The performance of KFCM is greatly affected by the parameter of the kernel function, while the selection of kernel parameter is extremely difficult in practice. To solve this problem, a Parameter Optimization-based KFCM (POKFCM) is proposed according to the idea that the distances between samples of the same class are closer than the distance between samples from different classes. First, initial clustering of dataset is completed by K-means method. Then the optimal kernel parameter is determined by calculating the distance similarity between the actual kernel matrix and ideal kernel matrix. Finally, the optimal kernel parameter is applied to KFCM. Clustering experiment results of six UCI datasets illustrate that POKFCM can effectively improve the clustering performance of KFCM.

Appropriate rule evaluation functions are important to improve the performance of classification algorithm based on rules. In order to obtain the comprehensible classification rules, an adaptive artificial bee colony algorithm, called A_ABC algorithm, is proposed. The A_ABC algorithm can adaptively select a appropriate rule evaluation function for the given data, and effectively process both discrete attributes and continuous attributes. The proposed A_ABC algorithm is evaluated by experiment using different standard real datasets, and compared with existing classification algorithms. Results show that the A_ABC algorithm can solve classification problems more effectively than the existing algorithms.

To solve the transmission delay exorbitant problem in P2P live streaming system, we develop a dynamic layering model based on the uploading bandwidth of peers, and introduce its quantitative basis and method of the initialization and dynamic adjustment. Based on this model, we propose a new parallel transmission algorithm. Meanwhile, each layer of the peers generates seeds at geometric growth rate and transmits them to the lower layer continuously. In mathematical modeling analysis, when the parallel transmission algorithm divides the data content into sufficient units, the total time unit and average time unit costs for transmitting the data content to all the peers are better than the existing transmission algorithm.

A Spatial Verification method based on Local Regional Constraints (SVLRC) is developed to remove false positive matches. First, the local region range of a center match pair is calculated. Then, the constraint value of the centre matches is defined according to the number of other matches in the local regions and whether the center match pairs satisfy the condition of local region constraint is judged. If the condition is met, whether all the matches in the local regions follow consistent geometric transformation is estimated based on geometric order. Extensive experiments demonstrate that the SVLRC can improve the retrieval accuracy significantly with low computation cost.

In order to ensure efficient computerized detection of vehicles passing green toll lane of highway, a detection method, named PGM-OCSVM, is proposed for free toll lane of highway based on multi-feature fusion. First, the Principal Component Analysis (PCA) is used to filter and simplify the sample characteristics. Then, the Genetic Algorithm is applied for adaptive adjustment of bandwidth of kernel function (σ) and false acceptance rate (v), which are two important parameters of one-class SVM. Finally, a one-class SVM model is constructed to learn the samples and classify the results. Big data analysis demonstrates that the proposed PGM-OCSVM can effectively complete green-vehicle discrimination task. This method has been applied to the vehicle detection system in free toll lane of highway.

To make up for the lack of standard in data exchange of practical application, the conceptions of “self-standard data”,“data harbor”, “data dock” and “data pump” are proposed. Using these concepts, the data supplier can organize their data in a more flexible way. Data supplier can standardize the data provided, and store the data in "data harbor". For data consumers, they can obtain these data by means of data pump and parse the needed data from the data supplied by the data supplier. The definition and characteristics of self-standard data, the generating background, data exchange technical architecture based on self-standard data and data harbor, and the application areas are discussed in details. The effectiveness and feasibility of the self-standard data and data harbor technique are demonstrated by the realization of prototype system and enterprise application.

To solve the scheduling problem of various businesses existing in Bluetooth Piconet, a dynamic bandwidth allocation algorithm for multi-priority business of Bluetooth Piconet was presented, namely MPBA scheduling algorithm. In MPBA, the optimal polling interval can be derived by estimating data arrival rate and packet type for each link with high priority. By comparing the value of the optimal polling interval and the slot counter of a link MPBA decides whether to schedule this link. Simulation results indicate that the MPBA scheduling algorithm can provide better bandwidth requirement for high priority links with higher bandwidth utilization and lower scheduling delay than existing algorisms.

The timing errors in Orthogonal Frequency Division Multiplexing (OFDM), which occur when the first path is not the strongest one in the multipath fading channel, would incur a high probability of miss detection. To solve this problem, a timing synchronization algorithm was proposed, which can be used to exploit the cycle-right-shift property of channel impulse response to estimate precisely the first path delay. In this algorithm, first, the delay of the strongest path was estimated through coarse synchronization. Then, the channel impulse response was obtained using the Least Square (LS) algorithm, based on which the location of each path was determined according to the difference in a sliding window. Finally, the first path was detected using the adaptive threshold approach. Theoretical analysis and simulation results show that, compared with the existing methods, the proposed algorithm can decrease the probability of miss detection and improve the system timing performance.

In P2P networks, due to the selfish behavior, all the nodes pursue the maximum individual gains, but the system cannot achieve socially optimal gain. To solve this problem, a charging scheme to the requesting nodes is proposed. Based on the online mechanism of the P2P nodes, a continuous time queuing model with random number of services is built. Using the method of a matrix-geometric solution, the system model is analyzed in steady state based on an unobservable queuing rule. The expressions of the average delay and activation ratio are given. By establishing a reward function, the strategies with Nash equilibrium and social optimization are investigated. With a reasonable pricing policy the P2P network is socially optimized.

By introducing a feedback branch with fixed weights, a new adaptive broadband beamformer based on the Generalized Sidelobe Canceller (GSC) is designed. The feedback weights are obtained off-line through approximating the band-pass filter whose passband covers that of the interference. Also, the relationship between the interference suppression capability of the beamformer and the number of poles of the feedback branch is investigated. Compared with existing beamformer, since the feedforward branch of the new beamformer is exactly the same as the GSC, the complexity and amount of calculations of the updating procedure for feedforward weights are reduced. Meanwhile, the fixed feedback weights guarantee its stability. Besides, the flexibility of changing the number of poles strengths its interference suppression capability.

The excellent degree method is widely used in performance evaluation of image segmentation algorithms. However, this method ignores the influence of image quality. Hence, the results have no reference value to the overall performance evaluation of the segmentation algorithm or the comparison of different segmentation algorithms. To solve this problem, the image factors interfering with the performance of the segmentation algorithms were analyzed. Then, the metric Activity Degree of Image (ADI) was proposed to quantify these factors. Finally, based on the ADI, a performance evaluation method of the image segmentation algorithms was developed, named Weighted Excellent Degree (WED) method. Experiment results show that, compared with the current evaluation method, the WED method has higher consistency degree between evaluation results and subjective assessment, and better monotonicity between evaluation results and image qualities. Thus, the proposed WED method is more effective in performance evaluation of image segmentation algorithms than the current evaluation method.

In order to reduce the complexity of motion estimation and improve the efficiency of the video encoder, a novel multi-level adaptive fast integer pixel motion estimation algorithm is proposed. First, based on the frame-level motion intensity of previous frame and the predictive motion vector of current block, the frame-level search range and macroblock-level search range are predicted, and the smaller range is taken as the final search range. Second, the macroblock is divided into low, medium and high motion types according to the macroblock-level motion intensity; the Diamond, Hexagon improved or UMHexagonS improved algorithmic templates are adaptively selected. Then adaptive motion estimation of the high motion type macroblock is taken in a certain direction based on the directivity of the motion vector. Finally, improvements are made on the inefficient parts of the UMHexagonS algorithm. Experiment results show that, compared with the full search algorithm, UMHexagonS algorithm and EPZS algorithm, the proposed algorithm can averagely reduce the estimation time by 70.29%, 19.12% and 14.11% respectively, while, the Peak Signal to Noise Ratio (PSNR) and bit rate remain almost unchanged.

In order to solve the problem of loop and energy-unbalance in ant colony routing algorithm, an improved algorithm is proposed. In the proposed algorithm, the combination items of ant identity are added to the Hello package and stored in the neighbor lists of other nodes by broadcasting, which effectively weakens the routing loops. Simultaneously, the pheromone updating formula is corrected that the accuracy of pheromone updating is improved at multi-node region. An energy-difference factor is introduced to improve the node energy-balance in the network. Simulation results illustrate that the improved algorithm can greatly improve energy-unbalance and weaken the loop effect.