Abstract:The dense correspondence of 3D facial surface is the premise and foundation of 3D face analysis. The majority of the techniques deform a template to fit the target, and the non-rigid iterative closest point (ICP) is the most widely used one, this method fits high-resolution 3D facial template mesh to 3D target face (scan face data) step by step. But this type of methods maintain the topology of the edge regions at the expense of edge precision, in order to ensure the dense correspondent between deformed faces. Aiming at this problem, a non-rigid iterative closed point algorithm combining topological structure loss was proposed, which keeps the topology of the facial edge regions without sacrificing the registration accuracy. Experiments show that our algorithm perform better than the state of art.

Abstract:The security of network control system has captured worldwide attention. For the frequent overflow caused by the disparity between buffer setting and practical requirement in the Modbus TCP protocol fuzzing test, a new data structure of improved application data unit capable to preventing the message length information from being lost is presented in this paper. Then principal component analysis (PCA) is used to reduce the dimensionality explosion risk aroused by the massive identical information which comes from the data relativity. At last, a probabilistic neural network (PNN) is deployed to estimate the vulnerabilities detecting possibility of the malformed data to be input, which makes the fuzzing test more efficient. The analysis and comparison to the experiment result denote that the input data is reduced by 8.60% via using the method presented in this paper.

Abstract:Aiming at the obstacle avoidance and path optimization for industrial robots in complex environments, a path planning strategy for robot obstacle avoidance based on improved artificial bee colony algorithm is proposed. Firstly, aiming at the problems of lack of search ability and easy to fall into local optimum for traditional artificial bee colony algorithm, tabu search is introduced into the search process of artificial bee colony algorithm. An improved artificial bee colony algorithm based on tabu search is formed, and applied to the path planning problem of industrial robot. The results show that the improved method can obtain the optimal obstacle path of industrial robot, and the optimization speed is fast and the process is stable, which can be used to solve the problem of obstacle avoidance path planning of g industrial robot.

Abstract:Aim at technical status of corresponding products at home and abroad, and test requirements for defense equipment against electronic countermeasures, a wideband microwave vector signal generator is designed. First, vector modulation is implemented on 300 MHz intermediate frequency carrier, the frequency of vector signal is expanded to 4 GHz through RF converting and filtering, On the basis, after micromave frequency converting and filtering, the frequency is extended to 18 GHz. A electrically tunable microstrip filter is used for RF filtering, switching band pass filter module is used for microwave filtering, it can achieve low loss, small ripple, good group delay and good rejection outside band, maintaining modulation quality and spectral purity of vector signals. Calibration of vector modulator using precise internal calibration voltage, eliminating the residual carrier, quadrature offset, I/Q amplitude imbalance of modulation channel and the influence of frequency conversion channel, ensure the quality of vector signals in the whole frequency range and at different operating temperatures. Experiments show that the frequency range of signal generator can reach 300 kHz～18 GHz, stray is less than -30 dBc, error vector magnitude is less than 4％.

Abstract:The ship rock data is one of important data which need to be handled real-time during the mission of track and control ship. In order to improve the accuracy of the ship rock data, the paper proposes an improved M-step maximum likelihood ship rock data predictive method. The proposed method uses the stable 41 point-endpoint smoothing algorithms to solve the low accuracy level of the beginning 210-point filtering algorithm, which is also called maximum likelihood method. Besides, the proposed method need less filtering data than existing 210-point filtering algorithm. The paper uses some ship rock data from a real-time mission as a simulation data, and the simulation results show the effectiveness of the proposed algorithm.

Abstract:Non-intrusive load monitoring based on event decomposition is widely application for less storage and fast calculation speed. Firstly, methods on extracting load steady state feature were given, typical household appliance identification feature library was concluded. From the library, load harmonic features were important for air conditioner and other small power appliance which have even harmonics. Then, influencing factors of harmonic feature extraction in engineering application were researched. Based on the principle of spectrum leakage of FFT algorithm, the influence of grid frequency dynamics and electrical harmonic phase angle jitter on harmonic feature quantity extraction were studied. A Multi-point mean solution is proposed to solve the problem of non-synchronous sampling caused by grid frequency fluctuations, and the method of extreme value difference is proposed to solve the influence of appliance harmonic phase angle. With the two methods, the base harmonic error can be reduced to less than 1%, and the even harmonic error to 2%~4%. Finally, with the experimental platform and engineering, the effectiveness of the harmonic improvement extraction method is verified, and the load identification accuracy can be effectively improved by more than 5%.

Abstract:Target detection in the background of sea clutter is an important part of sea surface radar signal processing. The detection of weak targets in sea clutter is based on the statistical characteristics of sea clutter, but the statistical persistence does not reflect the intrinsic dynamics of sea clutter. Therefore, the detection results are not ideal. Based on the chaotic characteristics of sea clutter, this dissertation reconstructs the phase space of the sea clutter, and particle swarm optimization (PSO) is applied to radial basis function(RBF) neural network kernel function parameters. In the optimization study, this method is validated by using IPIX radar to measure sea clutter with target in Dartmouth area. The results show that: PSO-RBF small target detection method has good predictability in the background of chaotic sea clutter. Compared with the general radial basis neural network, the improved algorithm not only has fast convergence speed but also has high recognition rate.

Abstract:Multi-UAV cooperative reconnaissance planning problem refers to the problem that multiple UAVs reconnaissance multi-targets to solve the problem of minimizing the number of UAVs and the shortest total driving path. The bat algorithm is an emerging swarm intelligence algorithm with broad prospects and significant effects in many fields. In this paper, for the multi-UAV cooperative reconnaissance planning problem, the scene is coded, and the bat algorithm is used to solve the problem, and the obtained results are compared with the results obtained by genetic algorithm and particle swarm algorithm. The experimental results show that the bat algorithm has better stability and faster processing speed than the genetic algorithm and particle swarm optimization algorithm when solving the multi-UAV cooperative reconnaissance mission planning problem.

Abstract:The process of water quality assessment is multivariable, nonlinear and uncertain. The traditional particle swarm optimization training neural network water quality evaluation model has slow convergence speed and poor generalization performance. In order to overcome the shortcomings, this paper proposes a new model to use dynamic multigroup particle swarm optimization algorithm to train support vector machine, in which the DMPSO is used to optimize the parameters of the fuzzy neural network model. The model combines the search performance of PSO algorithm, the efficiency and robustness of SVM, which can improve the generalization ability of the model. Through the simulation experiment on the hydrological data, the results show that the relative error of this model is 2.74%, which is much lower than the 4.21% relative error of the traditional particle swarm optimization. It is proved that the efficiency and accuracy of the model are improved, and is suitable for the daily water quality evaluation.

Abstract:In the process of fault diagnosis of analog circuits, there are some problems which are insufficient extraction of fault feature information and feature information redundancy, for this, in this paper, a fault diagnosis method for analog circuits based on maximum overlapping discrete wavelet packet transform (MODWPT) and local Fisher discriminant (LFDA) is proposed. In this method, firstly, MODWPT is used to original signal processing and fault features extraction of the analog circuit. Then, due to the redundant information in the high-dimensional feature set, which is not conducive to pattern classification and recognition, LFDA is used to reduce the dimension of the high-dimensional feature set and obtain a lower-dimensional feature set which is more conducive to fault pattern recognition. Finally, support vector machine (SVM) is used as fault pattern recognition classifier, and a fault diagnosis model is constructed based on SVM. Through analog circuit simulation experiments, the maximum fault diagnosis accuracy of the proposed method can reach 99.17%, which verifies the effectiveness of the proposed method.

Abstract:Group recommendation has attracted significant research attention in recent years. In view of the problem of insufficiency of fusion strategy in group recommendation which cause the low accuracy, we propose an novel method to improve preference fusion strategy to increaandse the accuracy. We introduce the concept of item type proportion factor and calculate the type similarity between group type preference and user type preference. Meanwhile we design a score fusion formula to predict item score for the group. Finally, we carry out experiments and compare our method with several classic group recommendation methods using Movielens dataset. The results show that our method achieves higher recommendation accuracy than all the baseline methods.

Abstract:To better assess field X-frequency band RCS dynamic tracking performance of measuring system and the quality of the RCS measurement data, based on the uncertainty analysis and principle of RCS measurement, in this article, the uncertainty influencing factors in the process of RCS measurement from the radar system, environmental factors, calibration system are analyzed, researched and established the system uncertainty source, and combined with the specific measuring conditions, the uncertainty of system is given, so can fully grasp the quality and accuracy of the measurement data, provides support for describing the results of the measuring system preferably. At the same time, the uncertainty analysis method in paper can be combined with other measurement conditions, has extensive universality and applicability.

Abstract:This paper presents an image stabilization method based on deformable mirror. Firstly, the stabilization mathematical model based on plane mirror has been set to calculate the stabilization compensatory angle. Secondly, according to the key parameters of deformable mirror, the surface-shape error has been researched. At last, by experiments, the steady effect of deformable mirror has been verified and the stabilization error has been analyzed. The experiment results show that, the deformable mirror we used can realize the image stabilization function. Besides the absolute value of the image stabilization maximum relative error is 1.87%, and the corresponding stability accuracy is 2.11″.

Abstract:An image target was designed based on the principle of maximum length sequence（MLS）, using monocular vision and laser displacement sensor carried out One-dimensional absolute displacement test. In a relatively ideal laboratory environment, It’s show the standard deviation of the system’s repeated location detection data was less than 1 μm. According to the actual application environment and system installation status, for loss of focus from the lens, uneven illumination, deflection of the target and tilt of the lens may cause the detection error, conduct comprehensive experiments and analysis, The repetitive positioning of the one-dimensional absolute displacement detection system is discussed and proposed the method of improved. The experimental results show the standard deviation of the repeated positioning measurement data detected by one-dimensional displacement is less than 1 μm when the lens is out of focus; That the standard deviation of the non-uniform measurement data of lighting was less than 1 μm by improving the algorithm; When the targets under the condition of not greater than 5°, The standard deviation of the repeated positioning measurements is no more than 1 μm; And the camera angle is not greater than 3°, the standard deviation of the repeated positioning measurements is less than 1 μm. The last, the one-dimensional absolute displacement measurement is systematically calibrated by using laser displacement sensor. Under the above environment and installation error conditions, the root mean square error of the system measurement data is limited to 2 μm after the calibration.Test experiment and data analysis show the one-dimensional absolute displacement detection system is based on the principle of maximum length sequence can achieve high precision non-contact precision displacement detection, the system structure is simple and low requirement to implement process, advantages of easy installation and debugging.

Abstract:In the face of the measurement task of the contour surface of some mural panel components in the process of modern aircraft assembly and manufacturing, the single digital measurement equipment can no longer meet the measurement requirements. Therefore, the combined measurement technology based on laser tracker and articular arm measuring machine is studied in this paper. Firstly, the combined measurement system was built, and then the measurement process of the combined measurement system was developed and analyzed, and the deviation vector diagram and deviation distribution chromatogram were obtained. Finally, the combined measurement technology scheme was applied to the measurement task of the contour surface of a certain type of fuselage wall panel component. Through case analysis, the scheme is effective and feasible, and has certain application value.

Abstract:Study on optimization of the accuracy of navigation in walking posture corrector, in view of the lack of accuracy of the current attitude calculation technology, this is a design scheme of embedded stance posture correction in Linux environment. Based on a priori iteration method of correcting equation coefficients of position magnetic moment, an iterative error index function and an iterative formula are established, and numerical simulation experiments are carried out. In order to detect the attitude angle in real time, the integration of data collected by sensors is proposed including acceleration, angular velocity and magnetic field strength. The accumulated error of the integration is corrected by using the vector deviation of the three-axis acceleration sensor and magnetometer. The sensors transmit the final data results to the computer and mobile APP via the ZigBee and Bluetooth protocols to achieve the purpose of walking posture detection and correction. By the actual measurement results, the design improves the accuracy of walking position correction and strengthens the performance of real-time detection.

Abstract:Aviation simulation instrument is an important part of flight simulator. Conventional aviation instrument refitting method is difficult to develop and high maintenance cost. A simulation method is developed, which can exchange data and simulate the aviation instrument in appearance, display and operation. There are great significance for improving the integration and fidelity of aviation instrument simulation system. Digital design and CNC are used to make the aviation instruments panel and bezel; GLFW framework is used to render the graphical aviation instruments; hardware circuit is designed based on AVR MCU to realize real-time signal detection and lamp driving; ASCII code message is used for data exchange between simulation instrument panel and instrument simulation program. Through the test of helicopter flight trainer installation, the appearance, indication and operation response of the simulation aviation instrument is close to that of the airborne aviation instrument, which meets the design requirements, effectively improves the simulation standard and reduces the development cost. It is of great significance for the development of flight simulation training equipment.

Abstract:In order to reduce the loss of life and property caused by fire, an intelligent fire extinguishing vehicle system was designed and developed. This system adopts the structure of upper-lower computer. The STM32 chip is used as the main control chip of the lower vehicle, and the fire extinguishing intelligent vehicle moves along the preset path through the detection path information of infrared photoelectric sensor. The position of the fire source is detected by the flame sensor, and the fire extinguishing operation of the vehicle in manual mode, automatic mode and tracking mode is realized by the algorithm design. The upper computer software is developed by using C# language, and the data transmission between the upper computer and the lower computer is realized through WiFi communication, and the movement control, mode switching, real-time video, fire alarm and other functions of the upper computer PC to the car are realized through the program design. According to the test, the intelligent fire-extinguishing trolley system designed in this paper can well complete the fire-fighting work in three modes.

Abstract:In order to meet the management demand of charger in intelligent Substation, the management unit of the charger based on STM32 is designed. According to the analysis of functional requirements, the hardware architecture and software architecture are designed, the charger management unit is developed, and the system experimental platform is built. The experimental data show that it can realize the functions of information collection and parameter adjustment, local data display and key operation, remote monitoring two-way communication, logic control of charger and so on. The practical application shows that it can enable the staff to control the work of the charger in real time, improve the intelligent management of the system and meet the needs of practical application.

Abstract:Aiming at traditional switchgear, terminal and electronic components easily affected by the environment, moisture into the cabinet contacts with electronic equipment to produce condensation, reducing insulation performance, causing accidents, while not real-time intelligent control and processing, resulting the waste of resources. A new type of environmental humidity detection and dehumidification system for switchgear based on ARM is designed. The system takes STM32 as the core, uses the humidity sensor network to detect the humidity parameters, transmits the parameters data through RS485, displays the data in real time by the host computer, sets the threshold parameters, and the control center makes the dehumidification process. Comparing the four groups of data with the high precision humidity measuring instrument, the minimum relative error is 0.06%, the maximum relative error is 0.1%, and the accuracy is 0.1%. It can really show the humidity in switchgear. In 48 minutes, humidity was reduced to 67.2% and 50%, respectively, according to the comparison of the non dehumidification system. From the experimental results, the system has high accuracy, real-time and accurate display of humidity in the cabinet, intelligent dehumidification effect is obvious, can be very good detection and processing of the switchgear ambient humidity.

Abstract:Aiming at the problems of single factor and poor accuracy of meteorological observation in fishpond at present, a comprehensive meteorological observation system for fish ponds based on STM32 high performance processing chip is designed. By building functional modules such as data acquisition, data quality control and packet transfer, etc, the system can achieve real-time acquisition of meteorological observation data such as water temperature, humidity and radiation. At the same time, the message is transmitted to PC software for data monitoring and product processing. At the same time, by comparing and analyzing the operational data between the meteorological standard instrument and the system, solving the root mean square error of each element, the results are 0.2, 1, 0.3, 6 respectively, which complies with relevant meteorological business requirements, and the accuracy of the data collected by the system is preliminarily verified. The practical application results show that the comprehensive observation system has the advantages of stable and reliable operation, high measurement accuracy and high transmission efficiency, and can meet the needs of Agrometeorological services betterly.

Abstract:Aiming at the problem of weighing accuracy and low efficiency caused by irregular shape and uneven quality of weighing objects, an embedded multi-function combination scale control system based on STM32 single-chip microcomputer was designed and developed. The system introduces a modular design concept and adopts distributed control. The hardware is standardized on the power module, main control module, AD data acquisition module and stepper motor drive module of the system. The software aspect improves the efficiency and yield of the combination by establishing nested functions and optimizing the combination algorithm. After field test, when the combined speed is controlled within 0.5%/min, the error can be controlled within 0.5% to achieve the desired effect.

Abstract:In order to adapt to the rapid development of IoT technologies based 5G, the idea of using the ARM architecture as a terminal device for IoT has important practical significance. However, it is still unclear whether the ARM architecture can meet the 5G IoT terminal performance requirements. In particular, the processing delay of terminal for massive data will directly affect its feasibility.In view of this, based on the open air interface(OAI), this paper focuses on the Turbo decoding delay problem using the ARM architecture and compares it with the x86 architecture computer.The results show that the decoding delay based on the ARM architecture is 20%~25% longer than that of x86 architecture. Given the difference in the performance of the two architectures, this gap is in line with expectations.

Abstract:Using the fluid mechanics software fluent to numerically simulate the two ultrasonic wind transducers at different wind speed, the velocity nephogram， and the curve of the wind speed with time step on the centerline of the transducer has been obtained. And the effects of the two transducers on wind speed are analyzed and compared. Secondly, the rectangular transducer is taken as the research object. At different wind speeds and different wind directions, the variation of wind speed with wind direction on the wind path is simulated. The wind speed curve along the wind direction and the comparison chart of the curve of x component velocity with wind direction and the variation curve of x axis component velocity with wind direction of standard wind speed has been obtained. From these diagrams, we can see the influence of ultrasonic transducer on wind speed under different wind directions. From the simulation results, it can be concluded that the streamlined shape of the bullet-type ultrasonic transducer has less influence on the wind speed than the cylindrical transducer at high wind speed. In addition, the ultrasonic wind path should avoid parallel wind when designing the ultrasonic anemometer, that is, the path of wind measurement should be at an angle to the wind direction, and the angle should be about 60°.

Abstract:A multi-point temperature monitoring system based on single-chip microcomputer is designed to solve the shortcomings of traditional single-point wired control. The system includes the host and three slave modules. From machine using digital temperature sensor DS18B20 to test the temperature, the temperature signal is transmitted to MCU, MCU to temperature signal processing, the processed data to the wireless module nRF24L01, nRF24L01 module and then sends the data to the host, the host nRF24L01 after receiving the temperature signal, sent to the host MCU processing, control the LCD1602 display temperature, when the temperature more than upper and lower limit, the SCM will start peripheral circuit buzzer alarm. The actual test results show that the temperature error measured by the system is small, the system performance is good, the structure is simple, the stability is reliable, and it has good popularization value.

Abstract:Combining the characteristics of various existing object motion acceleration measurement methods, a low-cost and convenient motion acceleration measurement method based on MEMS motion sensor is proposed. The method uses multi-sensor data fusion technology to solve the motion posture of the object in real time, and then extracts the motion acceleration of the object from the measured data of the MEMS motion sensor. The feasibility of the method is verified by the MEMS motion sensor based acceleration measurement system. The experimental results show that the acceleration solution error of the method is 0.03 m/s2 at rest, which is basically consistent with the acquisition accuracy of MEMS accelerometer. The acceleration solution error of the method is 0.07 m/s2 when free-floating motion. The coupled motion acceleration will reduce the accuracy of the solution when the object is moving for a long time, but it still has high accuracy in short-time motion.

Abstract:The optic sensor salt density on-line monitoring system is a new technology of on-line monitoring insulator pollution. Due to the baffle above, the optic sensor salt density on-line monitoring system is not obvious to the reflection of rain. In this paper, the original equipment is improved, that is, double optic sensor salt density on-line monitoring system. When continuous shower or heavy rain, it has response that the equivalent salt deposit density measured by the light sensor. By analyzing the measured data, the basic data obtained from the measurement are almost the same, while by comparing the data, it is the same that the overall trend of the measurement data obtained by the upper sensor and the insulators. finally, the necessity and feasibility of the system are verified.

Abstract:In view of the serious harm of propellant leakage, a monitoring alarm system for propellant leakage based on CC2530 microcontroller and ZigBee wireless technology is proposed in this paper. The system mainly consists of wireless propellant leakage monitoring gas sensor, dual mode monitoring alarm host and master computer. The sensor and the alarm host transmit the signal through the ZigBee wireless technology. The alarm host and the master computer in the monitoring room transmit the data collected by the alarm host through Ethernet. The experimental results show that the wireless transmission of the system is reliable, and the monitoring error of propellant is less than 3%. The system realizes the wireless monitoring of propellant leakage, greatly reduces the installation time of the system, and has a strong mobility, not only realizes the fixed mode propellant leakage monitoring, but also realizes the leakage monitoring under the maneuver mode.

Abstract:The flexible joint mechanism with variable stiffness is affected by joint damping when it is controlled by active and passive composite drive, which leads to poor global steady-state of driving regulation. An optimal control design method for flexible joint mechanism with variable stiffness based on compound amplitude saturation nonlinear state feedback is proposed. The dynamic model of flexible joint mechanism with variable stiffness is constructed, and the equivalent stiffness of flexible joint is used. The damping force and the compression of the joint spring are the control constraints. The controlled object model of the flexible joint mechanism with variable stiffness is established. The adaptive damping error is corrected by using the amplitude saturation nonlinear state feedback control method. According to the characteristics of active and passive composite stiffness, the driving inertia parameter of flexible joint mechanism with variable stiffness is adjusted, and the driving regulation control of joint mechanism is realized. The simulation results show that the stability of the flexible joint mechanism with variable stiffness is better and the driving ability is better.