Abstract: The public opinion topics are usually caused by the sudden events,and social network sites( SNS) have become the important communication channels of the public opinion topics because of their large scale of users and the characters of open,real-time and interactive. Therefore,studying the propagation mechanism of public opinion topics in SNS will be conducive to analyzing and monitoring the propagation process of public opinion topics. However,it is difficult for the traditional information propagation models to describe the propagation and evolution of the public opinion topics in SNS. This paper analyzes the information interaction mode and propagation characteristics of the public opinion topics in SNS,and then the propagation model of public opinion topics in SNS is built up based on SIR model in the scale-free network. The model considers internal infection probability,external infection probability,immune probability and direct immune probability as the important parameters in the propagation process. The simulation results show that the model established in this paper can well describe the propagation law of public opinion topics in SNS.

Abstract: For the probem that indoor objects or persons use active radio frequency identification technology,the paper presented an RFID indoor positioning algorithm based on BP neural network. The localization algorithm introduced reference label assisted positioning,and used BP neural network to establish the field strength signal conversion model. In the model,input received signal strength value,output the path loss coefficient,improved the accuracy of the path loss coefficient,and reused the distance-loss model to achieve precise positioning,thereby reducing the positioning error. Compared with traditional RFID localization algorithm,the simulation results show that the positioning accuracy of the method has been significantly improved,there are potential applications in warehouses,prisons,supermarkets and other indoor environments.

Abstract: Based on the instability,quickness and velocity limitation of 6- DOF manipulator in the process of grasping objects,a Time- optimal 3- 5- 3 polynomial interpolation trajectory planning algorithm was proposed based on Differential evolution algorithm( ED). According to the velocity limitation of manipulator,the characteristics of simple structure and easily adjusted parameters of ED prove the effectiveness of the method. The comparison between the algorithm and traditional spline interpolation on the position,velocity and acceleration of the movement shows that the running time of the algorithm is shorter,and its stability and fluidity are better.

Abstract: In the process of permanent magnet synchronous motor speed control,external interferences,parameter changes and imprecise system models have great impacts on control precision. In this paper,a dual loop control,current loop and velocity loop,is adopted in motor control system. SVPWM modulation vector control is adopted by current loop,sliding adaptive control is adopted by velocity loop,sliding mode control is not sensitive to external interference and parameter changes. By combining with adaptive control,the buffeting generated by the sliding mode control can be weakened. MATLAB platform is used,simulation results show that motor starting speed and current overshoot are small in sliding mode adaptive control,and steady- state operation can be achieved quickly; when disturbance is added to the system,speed and current have small fluctuation,and steady- state operation can be quickly restored. Compared with the simple sliding mode control,sliding mode adaptive controller has fast response,small overshoot,and buffeting can be overcome,it has good steady- state accuracy and dynamic performance.

Abstract: The adhesion control is one of the difficult problem for locomotive traction control systems. In traditional adhesion control methods,the fixed control parameters of locomotive cause much locomotive traction loss. To optimize the adhesion utilize and the traction of locomotive,an adhesion control method which is based on the fuzzy road identification is proposed. The method identifies the road condition of locomotive by adhesion coefficient,which is estimated through the disturbance observer,and the difference value of locomotive axle reference velocity and axial velocity. The method switches the idling discriminant parameters and the output function of traction torque. The simulation model of electric motor coach is established to verify the effectiveness of the method. The simulation shows that traction loss can be reduced by the method,and the method can improve the using of adhesion.

Abstract: An optimized task scheduling model of IOT based on combination weighting approach is proposed According to the characteristics of multi-core task scheduling in IOT,the task selection model under the state of multi-core operating in IOT is established,and the task selection problem is transformed into multiple attribute decision making problems Through combination weighting approach,the weight of each attribute is calculated The task required to complete is sorted according to the weight value size,and the task required to complete with the largest comprehensive attribute value is preference to carry out On the basis of top performance task selection method,the task scheduling model in IOT for resource optimization is presented,and the optimized multi-core task scheduling in IOT is completed Simulation results show that the proposed method takes less time to complete the same task than the traditional methods

Abstract: In order to overcome the torque ripple and speed instability of BLDCM,this paper proposes a new control method based on self- adaptive fuzzy PID optimized by Particle Swarm Optimization Algorithm. The particle swarm optimization algorithm is applied to design the fuzzy controller,and the motor speed can be controlled smoothly and the load disturbance can be inhibited. The simulation model of a brushless DC motor with fuzzy PID controller through MATLAB is built,and the operation is simulated for motor starting as well as speed and load change. Simulation results show that the system has good performance with rapid response,ideal stability,strong robustness to the change of system parameters and load disturbances.

Abstract: The friction problem of rotary steering drilling platform was studied,and the generalized mathematical model of controlled object with friction was established. Aiming at the uncertainty of friction model,stair-like generalized predictive control algorithm was proposed to improve the accuracy and stability of the control system of stabilized platform. It can not only retain the advantages of traditional generalized predictive control,but also avoid to solve the inverse matrix online,meanwhile the security of this algorithm has been improved. This algorithm was applied in the control system of tool face orientation,and simulation studies were carried out. Simulation results show that the algorithm can guarantee higher control precision and good dynamic performance,as well as has strong anti-interference ability to time-varying frictional and good robustness to parameter uncertainty.

Abstract: In order to research the economy of the micro- grid with micro- turbine,the economic optimization model based on maximizing comprehensive benefits was set up on the premise of satisfying the constraintson system operation and demands of loads. At island model and grid-connected model,optimization models were developed in the micro-grid taking into account equipment depreciation cost,operation and maintenance costs,cost of fuel,power purchase cost and reduced environmental cost. The swarm optimization algorithm was used to solve this model,comparing and analyzing the comprehensive cost in the running mode with and without micro-turbine and the output of distributed generation. The results show that the model can ensure the reliability of electricity and the power configuration scheme with micro-turbine can ensure best economy. That provides a theoretical basis for the planning of micro-grid.

Abstract: In order to solve the collision avoidance and obstacle avoidance problem according to Multi-Agent formation through the obstacles area,an obstacle avoidance algorithm is optimized by the improved artificial potential field method,the Multi-Agent formation can effectively pass the obstacles area,and after passed the obstacles area,the Multi-Agent formed again. First,the Multi-Agent model is improved,Agent model is built based on the speed vector with a visualization range of speed. Then,the obstacle avoidance problem of Multi-Agent is solved using the Vectorial Artificial Potential Field(VAPF) method. Finally,by adding " rotational force" to the force of agent,the agents can easily pass the obstacles area,and solve the " local trouble". Simulation results verify the efficiency and validity of the method.

Abstract: The multi-ship DOA location is a common passive co-location method under the complex sea battlefield environment. The ship layout plays an important role on the detection zone and position accuracy of DOA location. Therefore the ship layout must be optimized on the basis of operational mission and geographic features of operational area. The ship layout includes three factors: number of ship,interval between ships and ship formation. How to configure the three factors with reasonable setting is the difficult problem of the ship layout optimization. The mathematical model of position error of the multi-ship DOA location is built. The position error distributions of DOA location under all kinds of layouts are simulated. By the comparison and analysis of the simulation results,the reasonable setting methods for the number of ship,interval between ships and ship formation under different location demands and sea areas are acquired,and so that the ship layout is optimized.

Abstract: Rutting is one of the important factors for vehicle hydroplaning in raining days Based on the analysis of vehicle driveability and lateral stability on the pavement covered by water, the rutting safety evaluation method considering driving safety under the condition of road waterlogging was put forward Using the Car Sim software to simulate vehicle lateral offset and lateral acceleration with different speeds, the rutting evaluation indicators on driving safety were set up It shows that vehicle lateral offset and lateral acceleration increase quickly and exceed the safety threshold easily when more than 80km/h speed On the rutting pavement covered by water, vehicle lateral offset may exceed the safety threshold firstly, and the vehicle may lose its driveability when rutting length is long enough to arrive the instability threshold

Abstract: This paper proposed an encryption optimization algorithm of improved elliptic curve cryptosystems under the certificateless public key cryptosystems. Initialization was conducted for the network communication system to be encrypted,so as to obtain the system initial state information meeting the requirements of algorithm,build the theoretical encryption model based on the improved elliptic curve cryptosystems,acquire the legal and valid keys of node in the form of elimination,and simplify the encryption process. Then the safety of various system nodes was evaluated,and the security of the key attributes was verified. The experimental results show that the improved algorithm for encryption optimization in large network communication under the certificateless public key cryptosystems,can simplify the password system deployment,and improve the efficiency of the encryption system.

Abstract: Multi-UAV cooperative task allocation problem is the key to multi-UAV cooperative control. In order to solve the task allocation model which is based on single objective function and can not provide large battlefield environment information for the decision-makers,based on multi-objective optimization theory,a multi-objective optimization model of cooperative task allocation was established,and the maximum voyage and maximum task execution time were treated as two optimization objective functions. On this basis,an improved fish swarm algorithm with the variation idea of the genetic algorithm was adopted for obtaining the multi-objective optimization solution set of multi-UAV task allocation,then the decision makers can select the best task allocation scheme according to their preference. Finally,the algorithm was applied to the simulation of multi-UAV cooperative task allocation,the simulation results demonstrate the convergence and effectiveness of the improved fish swarm algorithm.

Abstract: The armored simulation training has developed from skill training to unit simulation training Performance evaluation is an important part of armored unit simulation training system The reasonableness of the evaluation will have great impact on the training level and enthusiasm of troops The current methods are human-oriented and they are not objective and systematic Through analysis of the requirement and characteristics of the armored unit simulation training system,we established the training performance evaluating index system based on AHP to solve the above problem The responding mathematical model,the calculation method of the weight of each index and the rating method were given in detail Finally,taking an armored unit simulation training as an example,we evaluated the performance The score it gives is scientific and it has a good performance in an armored unit simulation training system

Abstract: Traditional Fourier transform cannot describe how the frequencies in time-varying signal change over time,while the time-frequency analysis methods are the effective tools to process time-varying signals This paper compares the performance of the time-frequency analysis methods such as the spectrogram,the Wigner-Ville distribution,the smoothed pseudo WVD,the local polynomial periodogram(LPP),the S-method,and the RGK time-frequency distribution In terms of the MSE of the instantaneous frequency estimation,the concentration measure,and the computation time,the paper compares the above 6 time-frequency representations for mono-component linear frequency modulated signal and sinusoidal frequency modulated signal Performance of the 6 representations for multi-component signals as well as the bat sound signal is also compared The comparisons provide the basis for choosing the proper time-frequency representations for different signals in different SNR environments

Abstract: Aiming at the problem that mobile robot is always influenced by the environment in practical applications,a new method based on probabilistic model checking was proposed for path planning. The main factors of environment that may have an influence on the robot were analyzed. The motion behavior of robot was considered as an uncertain action,then Markov Decision Process(MDP) model was built. Meanwhile,the properties were described in Probabilistic Computation Tree Logic(PCTL) to express complex and diverse needs of behavior. The model was verified and analyzed on the PRISM platform for finding the global optimal path and quantitative data. The simulation experiment demonstrates that this optimal path can meet the mission requirements and collision-free and always avoid complex environment areas to ensure that the robots complete the task in maximum probability. The comparison experiments demonstrate the correctness and effectiveness of the method.

Abstract: Aiming at the situation of completely unknown attributes' weights and experts' weights in interval-valued intuitionistic fuzzy multi-attribute group decision-making problems,in accordance with the idea of evidence discount,a method based on improved Dempster- Shafer( D- S) theory of evidence is used to make decision. The experts' interval-valued intuitionistic fuzzy decision-matrix is normalized and transformed into mass function. An attribution-weight calculation method is ascertained considering interval-valued intuitionistic fuzzy entropy,the multiattribute of experts' group towards project set is modified and integrated,and the evidence information of all experts towards project set is obtained. The calculation method of evidence conflict degree is established based on conflict coefficient and Jousselme distance and is used to compute the expert-weight,then the evidence information of all experts towards project set is modified and integrated and the ranking order of all the projects is determined. A numerical example is given to verify the feasibility and validity of this method.

Abstract: In order to avoid the slip of the driving wheel caused by the changes of rail adhesion conditions,a control method of rail identification based on fuzzy theory was proposed. Real-time creep speed and adhesion coefficient estimated by full-dimension state observer used fuzzy logic to determine the similarity between current rail and standard trail. Then,the adhesion peak point of current tail was quickly and accurately identified. Finally,the contact force of current track was fully utilized to dynamically adjust the output torque of traction motor. The proposed control method was simulated through four-axise electric locomotive model with MATLAB / Simulink. Simulation results show that the proposed control method effectively prevents the slip of the driving wheel,and improves the stability of train and railway transport efficiency.

Abstract: In cloud computing environment,for a data-intensive scientific workflow,the rational distribution of its task data files in multiple cloud data centers will largely impact its execution efficiency. In this paper,based on the dependence of scientific workflow task data,a data placement strategy and the related scheduling approach for scientific workflows in cloud was proposed,which can improve the workflow execution efficiency. The processing capacity differences of data centers and the bandwidth differences among them were also taken into account. The analysis and simulation show that the strategy can observably reduce the data transfer across data centers and the time cost of scientific workflow,and hence improve the whole efficiency of scientific workflows.

Abstract: In this paper,the modeling function of servo control system for aerospace linear electro-mechanical actuator( linear EMA) with high accuracy,broad band and heavy load is analyzed. Structure and parameters of current loop,velocity loop and position loop are designed and components of servo system are analyzed. In order to improve the accuracy of linear EMA servo system model,combined with the control mathematic model established using Simulink and linear EMA physical model built though Simscape,dynamic response of the servo system is simulated and analyzed. According to the simulation,the physical modelling in use of Simscape is closer to real system and linear EMA has a good displacement tracking ability. Correctness and feasibility of the controlling project are proved and the project satisfies the designed inputting requirement.

Abstract: The DC motor has a strong nonlinear characteristic. By using the given parameters,PID speed control method can improve the response speed and dynamic performance,but it will generate the overshoot. So the speed control system performance is not guaranteed. In this paper,we design a fuzzy self-turning PID control system with the basic knowledge of expert systems and expert control system. The system uses input error and its change rate to establish a set of PID adjustment rules in real time. Combined with the established DC motor model for simulation,the results show that the designed fuzzy self-turning PID controller improves the response speed of the DC motor,and makes a good solution to conventional PID control overshoot problem.

Abstract: To study the influence rules of the critical initiation speeds that the projectiles impact initiation shelled explosive with different materials and L / D ratios,so as to offer data reference for the armament design of projectiles,by using LS- DYNA software and the Lee- Tarver ignition and growth model,the numerical simulation of shelled PBX- 9404 explosive is researched when it is impacted respectively by three different materials of projectiles with the same mass,the initiation process is analyzed,the critical initiation speeds of the projectiles of three different materials with different L / D ratios are acquired,theoretical calculation model is established,and the results of numerical simulation are validated by detonation criteria. The results indicate that,among the three different projectiles,there are obvious differences in ability to initiate the shelled explosive. When the initiation point is not on the interface of shell and explosive,the faster of the impacting velocity is,the closer initiation point to the interface is. Besides,the bigger of the L / D ratio of projectile is,the higher of the critical initiation speed is.

Abstract: To solve the problem of automatic flight of quadrotor UAV indoors or in other complex environments which lack GPS signals,the attitude controller based on backstepping method with sliding mode and the PID position controller were designed respectively on the basis of nonlinear model of quadrotor UAV. Considering the high prices of laser range finder,the method based on infrared sensors and Extended Kalman Filter( EKF) was proposed to achieve indoor autonomous localization,which makes up the shortfall that the infrared sensor can only measure one point at a time. The performance of the designed controller and the localization algorithm were validated by simulation experiments,and the experimental results proved the validity and reliability of the designed indoor autonomous flight method of quadrotor UAV.

Abstract: Development of pure electric vehicle( PEV) system involves multiple disciplines,such as machinery,electronics,control etc. Its multi-domain modeling process not only requires model to be close to the practice of the system but also puts forward higher requirements to the integration ability of the model. To improve the integrated ability of the model and the credibility of simulation results,this paper adopts a more suitable language for complex system modeling-Modelica,and builds a simulation model of PEV which is composed of battery,AC permanent magnet synchronous motor,and suspension. Simulation analysis is conducted on the vehicle model about acceleration performance,grade ability,driving range and following features on the multi-domain modeling and simulation platform-MWorks. The results show that the error between the model simulation data and the real vehicle test data is quite small,which indicates that the structure and parameters of the vehicle model is reasonable.

Abstract: There are several interference factors in touchless palmvein capture system,which degrade the location accuracy of region of interest( ROI). In order to overcome the interference factors and improve the verification performance,"point set operation"is used to preprocess palmvein images,which analyzes and processes the regions directly. The valley regions between fingers,i. e.,the valley point set,are detected through the translation,intersection and union of point set of segmented palm. Four valley points are selected from the valley point set according to constraint conditions. With the help of the four valley points,the corresponding coordinate system is established to dynamically locate ROI. The experimental results confirm that the proposed"point set operation"has strong capacity of resisting disturbance and high location accuracy.

Abstract: In the process of high temperature measurement,using the traditional algorithm for high temperature measurement,the temperature measurement model is set up,the object being measured spectral emissivity of stability is poor,temperature measurement precision reduce problems. Therefore,an algorithm based on neural network is presented in the color of the high temperature measuring system of temperature measurement method. Using color digital camera to the high temperature object in all sorts of color light for calibration of temperature,using image recognition technology of image recognition,fusion transform aperture shutter combination method of measuring temperature will extend to the commonly used temperature range of producing high temperature,by a RBF neural network measurement model and calibration CCD spectral response bandwidth and the object being measured spectral emissivity of three sides facing the influence of the temperature measurement accuracy,establish the color of the precise method of high temperature measuring system of temperature measurement model. The color of the simulation experiment proves that the algorithm based on neural network method of high temperature measuring system of temperature measuring is of high accuracy and strong adaptability.

Abstract: Prediction accuracy of software reliability prediction model( SRPM) based on a single neural network is not high and this SRPM has low adaptability,and network structure of SRPM based on advanced neural network is too complex In order to improve the adaptability of SRPM and reduce the neural network structure in the case of high prediction accuracy,a new prediction model is proposed The weights and thresholds of the BP neural network are optimized by Firefly Algorithm( FA) in the training process of BP neural network by software defect data At the same time,in order to reduce the fluctuation of prediction by BP network,averaging method is used to deal with predicted results Based on those,software reliability prediction model is established by FABP According to 3 groups of software defected data,and the mean value of error and sum of squared errors are taken as measurement to compare prediction performance Simulation results show that the SRPM based on FABP which has a relatively simple network structure can improve the prediction accuracy and adaptability