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Electroless copper plating method combined with spark plasma sintering (SPS) was used to fabricate W-Cu alloy with low W-W contiguity. Results show that W-Cu alloy with low W-W contiguity and high relative density can be obtained by this method. With sintering temperature increased from 860°C to 1060°C, the relative density of W-Cu alloy shows a rapidly increasing tendency, but the W-W contiguity keeps at a low level. Compression testing results show that the ductility of prepared W-Cu alloy is sensitive to strain rate, and the failure strain of the W-Cu alloy shows obviously increasing tendency with the loading strain rate increased from 10-3 to 103.

An improved method for the determination of chemical oxygen demand (COD) is presented. This method is based on the standard method but using silver sulfate as a masking agent for the chloride and using the microwave for the digestion. The method gives tiny errors when the chloride of the samples increases from 606.6 mg/L to more than 30,000 mg/L. The method applies to the samples containing macromolecules and give better results when the sample is prehydrolysed.

Joint Beamforming and power allocation schemes are considered for cognitive radio (CR) multiple input single output (MISO) system in this paper. We considered the robust downlink beamforming and power allocation problem with per-antenna power constraints which is more realistic in practice, instead of sum-power constraint, under the imperfect channel state information (CSI). Since the given optimization problem is a non-convex problem which is difficult to handle, we transformed it into second order cone program (SOCP) problem, which can be solved efficiently. Simulation shows that the proposed scheme indeed has a better performance in CR system.

Dynamic stability parameters (dynamic derivatives) are important indicators for the control system design, orbit design and longitudinal and horizontal dynamic stability analysis of aircrafts. Methods that evaluate the quality and dynamics of an aircraft typically include flight experiment, wind tunnel testing and theoretical calculation, with one of the most important part of them being the obtainment of dynamic derivatives. Project estimation method derivative action is not considered suitable for boundary layer transition, flow separation and re-attached and the complex situation leeward area vortex small angle of attack linear range. Frequency domain is a dynamic non-scheduled periodic invariant system to get moving derivative calculation method, but the accuracy of the unsteady flow is much lower than the time-domain calculations. Currently, unsteady CFD approach represents a time-domain nonlinear aerodynamic characteristics predicted the most advanced level. Derivative prediction efficiency and adaptability under conditions of high angle of attack of the development trend of nonlinear dynamic derivatives were analyzed. As a global trend, obtaining dynamic parameters through numerical calculation is becoming a prevailing approach to dynamic parameter research.

NoC is a expand for SoC.The architecture of NoC is huge and complex,it leads to the crosstalk fault between internal transmission of NoC increasingly serious. Crosstalk serious impact on the signal integrity of on-chip system.A new test codes generator was designed by PSpice simulation software based on improved HT model. The generator was composed of a 16-bit counter and a 16-bit data selector.The generator was tested by PSpice software,the result showed that it satisfied the test requirements and had the advantage of portable. A crossstalk test method was proposed in this paper,we used this method on a test circuit,the result showed that the method could reduce the number of tests and save resource effectively.

Based on the analysis of the flight stability, the research progress of the unsteady aerodynamic model was comprehensively introduced. Bryan, first of all, the aerodynamic load of traditional dynamic derivative model is put forward, still used today in some engineering issues. However, Bryan state parameters of the model is not complete, not exactly reflect the unsteady aerodynamic force time history effect and nonlinear effect. Etkin models, by retaining the item of high order Taylor expansion, including the influence of nonlinear effect. Improved Etkin model can explain the actual flight of some of the common transient response, including due to stall the mutation and aerodynamic force/torque caused by unsteady flow dynamic bifurcation and chaos of the aerodynamic force/torque value and uncertain phenomenon. Finally, the unsteady flow field of a reduced order model development trends and application prospect were analyzed, and pointing out that the CFD simulation is still accurately predict the plane stability and handling the most important method.

Reasonable number of direction finding station is examined in multi-station bearing-crossing location. Though it is believed that increasing the number of station is helpful to improve the location accuracy, In the paper, the maximum likelihood estimation (MLE) as an example. The algorithms and the location error models are given. The simulation results show that the location accuracy will be improved quickly with the increase of the number of the measuring participants, but the improvement will be sharply slowed down if too many station involved, which also boost the complexity of location.

The new logging data of Daqing Oilfield every year is still scattered stored on a computer system in a separate document form at present, everytime use these logs are required to achieve through remote transmission,it’s very inconvenient and low retrieval efficiency. In view of this situation, we developed oilfields log digitizing system, establish a specialized database for Daqing Oilfield logs.It can achieve the logging data collection, processing, storage. With the computer database technology , network technology, it fundamentally reduce the manual statistics workload of reservoir evaluation personnel .

When the HVDC works in mono-polar operation or bipolar unbalanced operation, DC flows through the neutral point and causes DC bias magnetic of transformer around HVDC grounding electrode, which influences the operation security of transformers. Beside highly saturated core, it also causes the distortion of exciting current, increasing harmonics and leakage magnetic flux, and thus the losses, which in turn results in the structures of transformer overheating and insulation aging. Based on the principle of transformer DC bias magnetic and UMEC of transformer in PSCAD/EMTDC, electromagnetic transient simulation platform of transformer DC bias magnetic is built. Considering the effect of DC bias magnetic on different structure of transformer, three kinds of typical transformer that has been widely applied are selected including three-phase three-limb transformer, three-phase five-limb transformer, three-phase bank transformer. After comparing the differences between these three kinds of transformer, related parameters are set such as the core structure and mode of winding connection and so on.

Aiming at the features of nonlinearity, time delay, high dimension, big noise and others in the electric furnace smelting process, and the smelting process parameters some control process needs cannot be obtained by sensors, so the online parameter prediction method is of great significance for dynamic optimization control of system. In this paper, by using chaos theory and phase space reconstruction method, based on the idea of data-driven modeling, the temperature prediction model of crucible in the smelting process of ferroalloy electric furnace is established based on multivariate time series. Experiments show that the established data-driven prediction model can well predict the temperature change in the electric furnace smelting process, the root mean square errors of prediction are respectively less than 0.0715,and this has good guidance for practical production.

The virtually assemble model of the L-10/7 piston type air compressor with double actions was established under SolidWorks software. The kinematics and dynamics simulation of compressor’s crank-link mechanism were done by SolidWorks Motion, and the main results of simulation were given out, the results coincide with the date of design calculate. It can be used as the foundation for stress calculation and optimization design of the air compressor.

Industrial design has been developed in China for decades, it is with the constant collision of traditional Chinese culture and learned a variety of nutrients. Increasingly focused on product design aspects of traditional culture. Meanwhile, the product experience has become the core of the product design evaluation criteria. Many aspects of traditional culture will affect the user experience on the use of the product.

A form of static coupon following the boat was developed to carry the natural aging test for CF3011/BA9916-II composite in marine environment, and the weather resistance of composite in marine climate was studied. The changes of the morphology of the composite were observed, the changes of the quality ,tensile strength and interlaminar shear strength for specimen were analyzed, and the aging regulation was studied combining with the mechanism of hygrothermal aging for carbon fiber epoxy composite. The test results showed that with the aging time increasing, the moisture absorption of the composite increased, the mechanical strength decreased , and the plastic behavior of the material was showed.

：The application of Gauss pseudospectral method (GPM) to hypersonic aircraft reentry trajectory optimization problem with maximum cross range was introduced. The Gauss pseudospectral method was used to solve the reentry trajectory of the hypersonic vehicle with the maximum cross range. Firstly, the model of hypersonic aircraft reentry trajectory optimization control problem was established. Taking no account of course constraint, the maximum cross range was chosen as optimal performance index, and angle of attack and bank was chosen as control variable. Terminal state was constrained by position and velocity. Then GPM was applied to change trajectory optimization problem into nonlinear programming problem (NLP), and the state variables and control variables were selected as optimal parameters at all Gauss nodes. At last, optimal reentry trajectory was solved by solving the NLP with the help of SNOPT. The simulation results indicate that GPM does not need to estimate the initial cost variable, and it is not sensitive to the initial states and effective to solve trajectory optimization problem.

Laser cladding on K418 substrate using NiCrWMo powder by Nb:YAG laser was carried out for the repair of aero blades. The microstructure and microhardness of cladding layers were investigated. The result showed that using the correct nickel based alloy powder, at the craft parameter of electric current 160 A, pulse width 8mses, the frequency 4 Hz, the surface is balanced and continuous; the microstructure is close and uniformity; the cladding is well combined with the substrate without flaw; the rigidity of the cladding is higher than the substrate .

When UAV is implementing the simultaneous localization and mapping (SLAM) problem, the environment where UAV is flying exists unavoidable solid or moving obstacles because of its unknown character, which threatens the flying safety and the completeness of SLAM mission. To conquer this problem, an improved artificial potential field algorithm is proposed to simultaneously accomplish obstacle avoidance of UAV and SLAM mission based on a potential field function containing the distance from UAV to the goal and from UAV to the obstacles and the covariance of features. This algorithm is simulated and tested based on the built UAV plane motion model. The result shows that the proposed algorithm is effective to avoid the obstacles while implementing SLAM for UAV.

Based on the shoes design methods and processes of analysis and summary, the computer-aided design as a design tool to intervene to determine concept , design performance and design verification stages. TO build a market to meet customer needs as the guiding ideology of the computer-aided design system shoes finally.

This paper proposed a numerical model to investigate the characteristics of solar energy collected by the UAV’s surface in different flight conditions. The novel model consists of a solar radiation model and a solar-powered aircraft model. The solar radiation model describes the process of the sunlight (including visible and infrared light) reaching the surface of the panels, and key effective factors are included. The solar-powered aircraft model describes a conventional layout fixed wing aircraft model with solar panels on the upper surface of the wing. The whole model was solved numerically by a computer program developed with C language to calculate the total power that the panels absorbed under different conditions. The visual and numerical results were presented and discussed in details.

In this paper, the data mining technology and the mining process was explained; and several common methods of data mining were described. Based on the characteristics of the target value, application of text classification and textual association in the target value mining were discussed, and the process model of data mining concerning target value was also expressed.

Architecture design is an important part of the top-level system design, which is related to the development efficiency and quality. Description framework is how to describe the ideas and methods of architecture framework, which help relevant system research personnel understand the architecture. This paper analyzes and summarizes the model of the architectural framework home and abroad, combined with the current development of information technology and information system building needs, which uses the ability to guide the construction, and uses the demand to tract the function. Studying process of building the "new three mutual" (NTM) architecture description framework, this paper designed and completed a six-view architecture framework work, which is more responsive to the current needs of information systems development.

The montmorillonite (MMT)/multi walled carbon nanotube (MCNTs)/sulfonated polyether ether ketone (sPEEK) nanocomposite membrane were prepared by a method of solution casting for fuel cells application.The MMT and MCNTs were modified with sodium sulfanilateand poly (styrene sulfonic acid) (PSSA), respectively. The proton conductivity of theas-prepared membranes containing 0.5wt.% PSSA grafted MCNTs (PSS-g-MCNTs) and 0.5wt.% sulfonatedmontmorillonite (sMMT) increased by 0.013 Scm−1compared to the plain sPEEK.The tensile strength and yield strength of which increased by 34.37MPa and 34.20MPa relative to the 1.0 wt.% PSS-g-MCNTs loaded sPEEK, which indicated that PSS-g-MCNTs and sMMT may generate a proton conducting cocontinuous networkwithin the SPEEK matrix.

The NaCl-KCl-K2HfCl6 electrolyte successfully prepared by the reaction of HfCl4 with equimolar NaCl-KCl. Microstructure, surface morphology and components of the electrolyte were analyzed by XRD, SEM, and EDS. The results show that HfCl4 preferentially reacts with KCl when KCl and NaCl coexist or conversion relationship exist between Na2HfCl6 and K2HfCl6. The removal rates of oxygen reached 96.98%in electrorefining of hafnium attributed to high stability and low volatility of the electrolyte.

This paper designs and implements an IEEE 802.11n based mining high power access point to improve the disadvantages of low throughput, low communication distance which are met in current mining communication systems. By adding high power design to transmitting and receiving path, this design can get over more than 190Mbps throughput in lab testing, and can achieve more than 2km outdoor communication distance. Test results show that the mining high power access point is more suitable for mining application.

At present, wireless communication networks obtain preliminary application in underground metal mines, but the problems of anti-interference ability and communication capability generally exist. With regard to this situation, this paper proposed an IEEE 802.11n based multi-channel MAC protocol (MC-MAC), which supports multi-channel dynamically switching by evaluating real time channel packet received rate. MC-MAC can improve wireless networks’ data throughput, anti-interference ability, and communication reliability. To evaluate the practical performance of MC-MAC, This paper designed and implemented an wireless access point based on IEEE 802.11n as testing platform, experimental results show that MC-MAC can provide 193Mbps physical links rate and improve network anti-interference ability effectively, it is suitable for underground metal mine applications.

Polyamides (PI)-matrix composite films with inorganic nanoTiO2have been fabricated by employing in situ polymerization. Before addition, TiO2particles were firstly modified with coupling agents (KH550). The electric breakdown strength and micromorphology of hybrid films were characterized and investigated. Results indicated that nanoTiO2particles were homogeneously dispersed in the PI matrix for the addition of coupling agents and the electric breakdown strength of PI/TiO2composite films with KH550 were better than unmodified PI composite film. The breakdown field strength and tensile modulus of PI composite film with the inorganic content of 5 wt% were 200.1 (KV/mm). So the using coupling agent can effectively improve the compatibility and the homogenous dispersion of nanoTiO2particles in PI matrix. Meanwhile, the procedure described here offers an effective and simple method to produce PI/TiO2with excellent electrical needed for future application in electrical engineering field.

In high-speed mobile Orthogonal Frequency Division Multiplexing (OFDM) cooperative system, direct channel signal presents a step change due to carriage loss, which interferes with signal reception. In the proposed system, spread spectrum is adopted at relay to separate the receiving mixed signals. Subsequently, the fading coefficient threshold of direct channel is obtained by simulating outage probability of direct channel. Finally, separated direct channel signal is selectively received based on the ratio relationship between its current fading coefficient and the obtained threshold. The proposed receiving strategy reduces Bit Error Rate compared with other receiving methods. Moreover, throughput of the proposed system increases when the fading coefficient is higher than threshold.

C8051F020 MCU with rich external resources on-chip, in the electromagnetic stress test excitation signal or a power conversion circuit design, it can provide comprehensive control PWM signal and signal system, simplify the circuit hardware. This paper uses the voltage feedback signal through the C8051F020 single chip ADC0 conversion, and converts the result to send PCA0 module implements the 16-bit PWM signal output. At the same time generating a PWM signal, use ADC0 Window Detector achieved over the range of the input value alarm and protection, also, because the ADC0 is 12-bit, so, in the program for PCA0 values were trimmed, PWM signal output frequency can be set have been achieved and verified by experiment design conclusions.

The quantum-confined Stark effect on the optical absorption of intersubband transitions in an asymmetric AlxGa1-xN/In0.3Ga0.7N/GaN quantum wells is investigated by means of the density matrix formulism. The built-in electric field generated by the piezoelectric and spontaneous polarizations competing against to the external electric fields is considered. As the result, the influences of the built-in and external electric fields on the energy potentials and the eigen stares are discussed in detail. When the positive external electric field is applied, the peak values of the absorption coefficients from 3-2, 2-1 and 3-1 transitions are reduced and moved to the lower photon energy levels. With the negative field, the exactly opposite results can be obtained. Moreover, it is indicated that the results of the wavelengths from the 3-2, 2-1 and 3-1 transitions are reduced by the positive external electric field and increased by the negative field.

This paper illustrates the design methods of machine tools based on the theory of Kansei Engineering. General attitudes towards the machine tools are measured by the Semantic Differential Method, the mapping between the design elements and the cognitive image is established through the Orthogonal Experiments, and the specific element style that significantly results in a certain image as well as the order of contribution degree from design elements towards images are obtained. Finally, the effectiveness of this method is verified by designing practice of a pipe processing machine.

The installation position of nozzle directly affect the efficiency of high pressure water jet cleaning. In order to improve the cleaning efficiency, the paper establish the three-dimensional structure and numerical model of the original nozzle assembly and the spiral nozzle assembly. The numerical simulation results show that, on the same boundary conditions, the effective hit range of the spiral nozzle assembly is greater and more uniform than that of the original nozzle assembly.The effective surge pressure of the spiral nozzle assembly is larger than that of the original nozzle assembly, spiral nozzle assembly can can reduce the blind cleaning area and improve the cleaning efficiency.

In Inertia confinement fusion (ICF) physical experiments, target positioning accuracy directly affects the success of target hitting. The proposed positioning method firstly used template matching to extract the target features in image, then calculated the target’s spatial coordinate and rotation matrix by integrating the feature values from three CCDs. We used a PI Hexapods Micro-robot to adjust the target to a desired position. The experiment results show the PI Hexapods Micro-robot is confirmed to be able to adjust the target in a desired position, which verifies the practicality of the proposed positioning algorithm to be used in the real ICF physical experiment.

The concepts of fuzzy reliability are introduced, and the model of fuzzy reliability calculation for cylinder liner wear life is set up. A fuzzy reliability calculation example of cylinder liner wear life for vehicle engine with 4 cylinders is given. The different of reliability calculation between the sample reliability and fuzzy reliability are discussed, and point out that the key for fuzzy reliability calculation is to decide the fuzzy range properly.

To understand the development situation of the worldwide public bicycle systems more fully, the comparison research on the representative public bicycle systems at home and abroad is summarized in several aspects including operating mode, charging method, technology application, implementation effect, etc. Finally, the experiences and lessons for successful operating of public bicycle system are concluded.

Elastic constants of purity and containing impurity metal aluminum were calculated, and the effects of impurity on the elastic constants were also studied. The effect of particle on micro-stress concentration and debonded stress of inclusion was researched. The mechanical relationship between the grains was defined by relationship of displacement and driving force in cohesion zone model (CZM).The method can be extended to research mechanical properties of other metals and alloys structures.

According to coal-fired power plant’s granulated powder preparation,storage and delivery processes, the existing problems of feed valves in the actual useing environment and job conditions.It was introduced to the principle about a new type of the feed valve,the form of structure and practical application.

The maglev chopper is a very important part in the maglev train technology. This paper briefly analyses the working principle of a kind of two-quadrant zero-transition soft-switching maglev chopper, discussing the choosing of the key parameters, also with the experimental study on the choosing of the switching-on time, the experimental results indicate that, if you choose the switching-on time correctly, the pulse spike and ripple wave at the switching-on time is decreased, the resonance degree is subdued, and the efficiency is improved.

The target of this design is to modify and innovate on the basic original bicycle. It not only can offer all travel requirements, but also can provide a simple table to supply the rest and entertainment. This article will elaborate the bicycle design idea, design scheme, transmission device design, Solid Edge Modeling and stress analysis by ANSYS.

Transmission planning is a complex optimization problem with multiple deciding variables and restrictions. The mathematical model is non-linear, discrete, multi-objective and dynamic. It becomes complicated as the system grows. So the algorithm adopted affects the results of planning directly. In this paper, a fast non-dominated sorting genetic algorithm (NSGA-II) is employed. The results indicate that NSGA-II has some advantages compared to the traditional genetic algorithms. In transmission planning, NSGA-II is feasible, flexible and effective.

In the research of electricity market, electricity pricing is a key issue. Transmission pricing affects the interests of generation company, transmission company and consumer. In this paper, a new method of transmission pricing is proposed .It is based on the short term marginal cost method and further considers capacity cost. Simulation results show that the method proposed can not only lead to short-run market efficiency by providing effective economic signals to generators and consumers, but also ensure the balance between income and expenditure of transmission companies as well as help them accumulate special fund for transmission network expansion.

Submarine pipeline failures usually occur at free span part, and free spanning pipeline is easily induced vibration by vortex, which accelerates the fatigue failure of pipe. Therefore, it is necessary to assess the strength of free spanning pipeline at regular intervals. In this paper, considering the effects of VIV, resonance assessment and yield strength assessment as well as buckling strength assessment are enumerated. And an illustration is calculated to verify the reliability of assessment method. This research may provide a guide for safety design, installation and maintenance of submarine pipeline.

In order to evaluate the impact protection capacity of armor material quantitatively, direct impact testing loaded by modified Hopkinson bar was used to simulate the impaction between penetrator and armor. Protection coefficient k was defined to describe the protective performance. Using the direct impact testing, Ti-6Al-4V specimens with different microstructure and thickness were tested. Results show that k decreases with increased impact velocity and increases with increased thickness of specimen. Under a given loading condition, binary microstructure exhibits the highest k, indicating the best protective performance. Moreover, its k shows the most sensitivity to thickness (mt) and the least sensitivity to impact energy (me), which means that its protective performance can be improved most efficiently by increasing its thickness and it will exhibit good protective performance in a wider impact velocity range. This new method can evaluate the impact protective properties of armor materials efficiently, which may have a broad application prospect.

In view of the product development situation in the apparel industry characterized by high consumption of raw materials, the author proposes to use raw materials for one garment to satisfy the function of raw materials for two or more garments. By determining the orientation of experimental products through market research, and using pattern transformation technology experiment of garments and related supplies, the author has designed and made the combination enabling mutual transformation of outdoor clothing and outdoor tent, thus extended the ecological philosophy of garment product development. Furthermore, the author leads consumers to ecological consumption through the eco-product development, and gives suggestions on virtuous cycle of low-carbon production and consumption in the apparel industry.

According to the high earth dam with a large volume, high construction intensity, tense schedule, numerous construction machines, complex technology, and a lot of unexpected risk factors, the construction transportation becomes poor if the arrangement for transportation to the dam is unreasonable, which may result in schedule delays. This paper discusses the system of the real-time 3D visualization on network environment which is based on Unity3D engine, and the query of real-time three-dimensional visual information for transportation to the dam on the network environment is achieved. Users can have a real-time view of the dump truck during transportation and optimize the arrangements of construction organization. The results of research have great practical significance.

This paper presents a vision-related technique for 3-D position measurement. The proposed method utilizes the genetic algorithm (GA) and unprocessed grayscale image input from vision, in order to perform recognition of a target being imaged with known target object shape. The problem to recognize the target shape and simultaneous detection of the position, is converted to an optimistic problem of a model-based evaluation function, named as surface-strips model-based fitness function that consists in the computation of the brightness difference between an internal surface and a contour-strips. In order to evaluate the proposed 3-D recognition method, experiments by an unprocessed grayscale image have been input to recognize a ball in the image. The results show the effectiveness of this method for 3-D position detection.

In CR systems, resource allocation is very important, which can be operated by different rules, according to the different purposes. In this paper, we focus on subcarrier allocation in CR systems, where primary and CR users co-exist in adjacent bands, while keeping the total interference introduced to the PU band below a certain threshold and the total power allocated to the CR users under a constraint. First, we investigate Max-Rate subcarrier allocation algorithm (MaxR-SAA) which can achieve maximum transmit rate of the CR system. Then, focusing on the fact that the less interference introduced to the PU band, the better the PU can work; we proposed a Min-Interference subcarrier allocation algorithm (MinI-SAA). Further, aiming at achieving fairness among all the SUs, we propose a subcarrier allocation algorithm, which is termed as Fair-Rate subcarrier allocation algorithm (FairR-SAA). Numerical results are obtained for the behaviors and performance of our proposed algorithms.

The major instable modes of the gravity retaining and protecting structure for foundation pit are overturning and slipping. Because of the stability of these geotechnical problems is affected by many uncertain factors, the stability analysis of them should be involved in the scope of the fuzzy and random event. Therefore, based on the theory of probability and fuzzy mathematics, the random and fuzzy characteristics were took into account, the calculating model of the fuzzy reliability of the gravity retaining and protecting structure for foundation pit was established. Through an engineering example’s calculating analysis of its overturning and slipping instable modes, the fuzzy instable probability and reliable index are calculated, some relevant conclusions are acquired via comparing with the traditional safety-coefficient method, and the feasibility of the fuzzy reliability method is testified.

For description of rotor-bearing system, a symmetrical flexible rotor supported by two turbulent journal bearings is modeled. The analysis of the rotor-bearing system is implemented under the assumptions of turbulent lubricant flow and a long bearing approximation. The bifurcation and chaos behaviors of the system are investigated for various rotational speeds. The motion equations are solved by the self-adaptive Runge-Kutta method. The numerical results show that the bifurcation of nonlinear responses of the system varies with the rotational speed of the rotor. It is found that the rich and complex dynamic behaviors of the system include period-1, period-doubling, quasi-periodic and chaotic motions etc.

In recent years, the security of software becomes one significant feature of software. This paper improves trustworthy software engineering through a knowledge based expert system. We propose the knowledge collection and organization method, and threats analyzing algorithm in detail which are the kernel of the expert system. The software threat information is divided into threat state and exploit, and stored in the knowledge database together with the state production and exploit production representing the relationships between threat state and exploit. The threat analysis calculates the threat degree quantitatively of an application based on this knowledge in a formal way and give security advice to mitigate threats. Our method can reduce the work of an experienced security expert which is time consuming and economic costly, therefore popularizes the trustworthy software engineering.

Accompany with fast development of location technology, more and more trajectories datasets are collected on the real applications. So it is something of value in the theory and applied research to mine the clusters from these datasets. In this paper, a trajectory clustering algorithm, called Density-Based Spatial Clustering of Application with noise (Tra-DBSCAN for short), based on DBSCAN that is a classic clustering algorithm. In this framework, each trajectory firstly partitions into sub-trajectories as clustering object, and then line hausdorff distance is used to measure the distance between two sub-trajectories. Next, DBSCAN is introduced to cluster sub-trajectory to form cluster area, and then connecting different moments of clustering area is regarded as trajectory movement patterns. Finally, the experimental results show our framework’s effective.

The influence of different traffic information on drivers’ day-to-day route choice behavior based on microscopic simulation is investigated. Firstly, it is assumed that drivers select routes in terms of drivers’ perceived travel time on routes. Consequently, the route choice model is developed. Then, updating the drivers’ perceived travel time on routes is modeled in three kinds of traffic information conditions respectively, which no information, releasing historical information and releasing predictive information. Finally, by setting a simple road network with two parallel paths, the drivers’ day-to-day route choice is simulated. The statistical characteristics of drivers’ behavior are computed. Considering user equilibrium as a yardstick, the effects of three kinds of traffic information are compared. The results show that the impacts of traffic information on drivers are related to the random level of driver’s route choice and reliance on the information. In addition, the road network cannot reach user equilibrium in three kinds of information. This research results can provide a useful reference for the application of traffic information system.