Abstract:Electric motor and reducer are the core components of electric power steering system of pure electric vehicles, due to the performance of institutional inertia and friction damping factors of the EPS system, the EPS system has the problems of slow response and returning not sensitively, proposing a control method of the fuzzy PID control strategy based on EPS system in order to reduce the back steering resistance, so as to improve the performance of EPS system. Among them, the establishment of the mathematical model of EPS system, the real-time driving conditions of pure electric vehicle EPS system of motor current, motor torque and wheel torque control with fuzzy PID control strategy, in order to verify the feasibility of the control strategy, building the pure electric vehicle EPS system hardware in the loop（HIL）test environment, Test results show that fuzzy PID control strategy adopted by the EPS. It also can improve the steering performance of EPS system under real-time driving condition.

Abstract:The non-isolated bidirectional DC/DC converter is widely used in composite power storage systems. Using two-way interleaved topology can effectively reduce the output voltage and current ripple of DC/DC converters. In order to improve the dynamic performance and overload protection of bidirectional DC/DC converter，The paper based on the supercapacitor-based standby power storage system, analyzes the modes of the two-way interleaved Buck/Boost converter in Boost mode as models, and the working processes of each mode are introduced in detail. The original large-signal model is derived. On the basis of the small signal linearization method, the AC small-signal state equation and its equivalent circuit model are further derived, and the transfer function of it is obtained. Based on this design, the compensation network of the controller is optimized, and the stability and transient response speed of the system are improved. Finally, the experimental verification is carried out. The results show that the double-closed loop control strategy achieves constant voltage current limiting and can respond quickly, it meets the needs of practical engineering application.

Abstract:Pattern tools as an important part of the software of integrated circuits(IC) test system. Its performance has direct influence on efficiency of automatic test system (ATS).Defined the function structure of pattern tools by analyzing. The key technique for developing pattern tools was researched, and focused on the contrast between the Table Control and the ReportX Control to design pattern tools. After analysis, pattern tools are accomplished through ReportX Control, and embedded in the domestic BC3192 ATE. Finally, in a real environment pattern tools in performance was validated though testing. Flexible application of ActiveX Control technology makes virtual instrument development more complete and powerful.

Abstract:Analysis of a large number of traffic accidents showed that pedestrians are the vulnerable participants in traffic. In order to protect the safety of pedestrians, it is necessary to improve the intelligent level of vehicles, and assist the detection of pedestrians in danger of accidents through on-board terminals equipped with intelligent monitoring capabilities, so as to timely give early warning. The intelligent mobile video monitoring terminal with pedestrian detection capability has been designed based on the aggregated integral channel model to meet the needs of vehicle-mounted intelligent monitoring. A pedestrian detection algorithm based on the polymer integral channel model has been designed for multichannel video processing platform composed of TI DM365 chipset and TVP5158, and typical scene experiments were conducted. Experimental results showed that the terminal can implement remote video monitoring via mobile network, and effectively complete pedestrian detection, which improves the level of vehicle intelligence and traffic safety.

Abstract:According to the requirements of a recorder mounted on the shell, combined with VB6.0 GUI which has the characteristics of simple development and efficient programming, and the powerful data processing ability of MATLAB R2016a, designed and implemented a PC software which include instructions issued, information analysis, reading data back and data processing based on the mixed programming. The software includes ground simulation source testing, data read back and data processing. Instructions are issued through a serial port, and read back dates by the 100M EMAC, separated and parsed by channel, output source data and the corresponding physical quantity file. After testing, the software can give precise instructions, and get the parameter information in time after the flight test to meet the work requirements.

Abstract:In order to avoid the error of measuring the parameters of plastic pipes in the construction of hard plastic pipes, a measuring system for detecting the movement of steel beads in pipes is designed. The hardware of the system is controlled by STM32F103 single chip microcomputer, and the key measurement module is ExEX-2E1-Z metal sensor and SCA61T-FA1H1G inclination sensor. The system software mainly uses KEIL 5 software to compile the STM32F103 single-chip microcomputer, in order to drive the metal sensor and inclination sensor to measure and analyze the data, get the movement of the steel ball, and display the measurement results of the movement of the steel ball through the color LCD module. In the measurement method, the least square method is used to establish the calculation model of inclination angle, and curve fitting is carried out to achieve angle measurement. The overall function of the system is to measure the number, direction, period and angle of steel balls in non-transparent hard plastic pipes without machining marks.

Abstract:In order to improve the working time of inclinometer in coal mine while drilling, a measurement scheme based on low power consumption mode is proposed with STM32 embedded chip as the core. Using magnetic sensor and acceleration sensor with special driving chip to sense the earth magnetic field and gravity field, then can obtain the drilling attitude information. By researching the low power consumption mode of STM32, the instrument can enter the dormancy state in non-measuring time to reduce the power consumption of the instrument and increase the working time. Through field industrial test, it is proved that under the premise of guaranteeing the measurement accuracy and time synchronization, the single use time of the instrument is more than 60 hours, which fully meets the requirements of drilling trajectory measurement.

Abstract:The system proposed a remote glass breakage detection and alarm method based on MSP430 and ZigBee. In order to design a high-precision and low-cost glass breakage detection system, the design algorithm is based on the characteristic analysis results of typical glass breakage signals. Remotely transmit glass break alarms via onboard buzzer and ZigBee. The processing procedure of the glass rupture detector is mainly divided into two stages. The first stage mainly filters and extracts the signals collected by the microphone, and the second stage judges and compares the characteristics of the first stage to detect the broken glass. through the simulation analysis and actual experiment of the typical broken glass broken signal, the experimental statistics show that the accuracy of the system detection of the glass reaches more than 95%, which is much better than the existing glass broken detector.

Abstract:Aimed at the deflagration and detonation problem caused by the geometrical features change of bullet gunpowder brought by bullet structure deformation during the penetration process, a projectile-borne storage testing system was developed to acquire the stress and strain state of projectile. This system based on FPGA+STM32 dual controller realized the function of multi-channel strain signal conditioning collection, data storage and communication. The system adopted the strain signal as the inner trigger signal and used the digital potentiometer realizing the automatic strain bridge balancing to reduce the strain signal offset caused by temperature variation and strain gauge sticking deformation. The STM32 program-controlled power supply is used to launch the main acquisition system at fixed time to reduce the power consumption. The verification test shows that the system can complete the sampling and data storage of strain signals, and it has certain application value for penetrating strain test.

Abstract:Mock technology plays an important role in improving the independence and comprehensiveness of software unit testing. The existing Mock generation framework needs to write the logic of Mock method manually, which leads to heavy workload and possibly introduce human errors. In view of the low efficiency of Mock method construction in testing, an aided generation method of Mock based on data driven idea is proposed, which defines the Mock model to describe internal logic of the implementation, so that the input and output data are independent of the test script. Firstly, through the analysis of programs under test, the simulated method and its input and output parameters are found and analyzed. Secondly, the input and output relationship is modeled. Thirdly, the Mock method is generated for the simulated method based on the input and output relation. Finally, the simulated method in programs under test is replaced by the Mock method. The effectiveness of the proposed method is proved by experiments.

Abstract:The potential transformer is an important measuring device in the power system, temperature is one of the main factors affecting the accuracy of its measurement. In order to analyse the temperature field distribution of voltage transforme and enhance the heat dissipation ability of potential transformer, the coupling of temperature field and fluid field are calculated and analyzed by ANSYS software and CFX software. this paper takes 10 kV electromagnetic potential transformer as the research object. A simplified simulation calculation model is established. The simulation is based on scanning and subdivision, and the air convection heat transfer was considered. Through simulation calculation, the cloud chart of the temperature distribution of the potential transformer and the location of hotspot temperature are obtained. The calculation results can provide basis for temperature correction and local temperature rise measurement. At last, the factors affecting the temperature characteristics are analyzed. The results show that, low voltage top winding is the most important part of voltage transformer, and is the key to temperature monitoring. And the thermal conductivity and viscosity of oil have little influence on the temperature field in normal temperature range, which can be ignored. The convective heat transfer coefficient of the side surface has a great influence on the hot spot temperature. The heat dissipation ability of the voltage transformer can be enhanced by increasing the heat transfer capacity of the side surface.

Abstract:Aiming at the death of detained children in school bus, a detection and alarm system based on ZigBee technology is developed. The system detects the children′s detention through the sound sensor and infrared sensor in ZigBee wireless sensor network, and uploads the data to the control center to judge if there is any abnormality. If there is an abnormality, the control alarm system gives the sound and light alarm prompt, and sends the alarm short message to the designated number through GSM module. The design gives full play to the four advantages of ZigBee wireless sensor network: low power consumption, low cost, distributed and self-organizing. The function of the system is realized by software and hardware design. The experimental results show that the system has high success rate and short response time in detecting abnormal situations. It can play an escort role for the safety of children′s lives.

Abstract:In order to solve the problem of low efficiency, low function, large weight and complex circuit, a bidirectional DC-DC converter is designed to realize the high efficiency of constant current charging and constant voltage discharge for lithium batteries. The main control unit is based on the STC12C5A-60S2 microcontroller and uses a synchronous rectifier Buck-Boost circuit. The drive part controls the power MOS tube with IR2104 as the center. Constant voltage charging range 1～2 A, current step value not more than 0.1 A, current control accuracy not less than 5 %, charging efficiency greater than 95%. The constant voltage discharge voltage is 30±0.5 V, and the discharge efficiency is greater than 90%. The experimental results show that the whole design prototype has simple circuit, high charging and discharging efficiency, and no more than 500 g in weight, and has a certain practical application value.

Abstract:Based on the advanced metering infrastructure （AMI） user measurement data, this paper aims solve topology verification of city LV power distribution network. Firstly, the typical structure of city lv power distribution network was analyzed, and belonging topology and phase topology were defined. Then the topology verification models were researched, including circuit model and math model, and the method of multi-variate linear regression is studied. Combining the power network operation, topology verification framework was given, and the detail verifications of belonging topology and phase topology were proposed. Finally, taking the three typical communities in Hefei as an example, the verification results were demonstrate. The example shows that the accuracy of belonging topology verification is 100%, and that of the phase topology is 95%.

Abstract:With the continuous development of battery technology and extensive application of mobile electronic devices, battery test experimental platform becomes more important in the study of the process of exploring battery. In order to achieve real-time monitoring of the battery voltage, current and temperature data, and the charge-discharge state of the battery switching function, a design based on LabVIEW battery test experimental platform. Experimental hardware and software platform composed of two parts, the first data acquisition card interface circuit and the charge-discharge state of the switching circuit introduces hardware circuit hardware composition. The platform uses LabVIEW to develop the host computer, and then the main software components of the system are described from the aspects of electronic load communication module and data acquisition and digital output module. Finally, the experiment shows that the platform has a good real-time test function, which can monitor the health status of the battery in real time.

Abstract:The atherosclerotic plaque in the intravascular ultrasound image is mainly thickened by the intima and endominal tissue, which leads to the narrowing of the transverse section of the lumen and the identification of the types of atherosclerotic plaques, which can provide guidance for clinical treatment. Atherosclerotic plaques were mainly composed of lipid plaques, fibrous plaques and calcified plaques, and their echo intensity increased in turn. The texture feature information of arterial plaque image is extracted from the distribution of image pixel gray level in space, and three kinds of feature extraction methods are selected, such as GLCM, LBP, NGL. The extracted features are classified by the support vector machine (SVM) and the error correcting output codes (ECOC). The results show that the classification accuracy of the three feature extraction methods is better.

Abstract:To meet the requirements of rapid detection of fiber cross-section geometry parameters in the measurement of industry, digital image processing technology is used to realize fiber geometric parameter measurement. The high-contrast fiber secondary coating layer region is segmented based on Otsu method; the edge detection is performed on the low-contrast fiber primary coating layer and cladding layer based on the improved Canny algorithm. The algorithm uses the local region distance threshold based on the traditional Canny algorithm. The method replaces the high threshold in the double threshold method to realize the single edge response principle; the curve is fitted to the edge based on the combination of the quadratic curve normalization method and the homogeneous equation method, and the Gauss-Newton iteration method is used to solve the fiber geometric parameters. The test results are compared with the high-precision fiber tester FGM-502, the results prove the validity and accuracy of the fiber detection algorithm studied in this paper, and the accuracy meets the requirements of enterprise fiber geometry parameter detection.

Abstract:With the development of computer image process technology, traditional manual selecting has gradually been replaced by automatic selecting equipment in the selecting of the colonies. The core of the automatic screening instrument is the colony image recognition module. The key to the colony image recognition lies in the image segmentation technology. This paper proposes an improved watershed segmentation algorithm. The algorithm first uses Gaussian filtering to remove image noise, then performs morphological processing on the denoised image, then performs chamfer distance transformation to obtain the colony distance image, and then fills the cavity information by morphological method, and then performs the labeled region. The watershed is segmented, and finally the region is merged to gather the similar regions, so that the final segmentation image is obtained. The accuracy of colony image segmentation using the improved watershed algorithm proposed in this paper is 93.4%, while the traditional watershed algorithm has a segmentation accuracy of 75%, it can be seen from the comparison with the traditional watershed that the improved algorithm better suppresses the over-segmentation of the traditional watershed and greatly improves the accuracy of recognition.

Abstract:With the development of optical technology, higher requirements have been put forward for optical components. The accuracy and veracity of detection is an important part of optical components. The registration of defective images is a very important link. Therefore, it is necessary to study the registration of defective images. Aiming at the defect image registration algorithm, the principle and process of SIFT algorithm based on feature point matching are introduced. The experimental platform is programmed by MATLAB software to obtain the defect image. The defect image is registered and mosaic by SIFT algorithm, and the complete defect image is obtained. The experimental results show that the algorithm can effectively register the defect image and lay a good foundation for the subsequent defect information extraction.

Abstract:Our nation has a vast territory, which holds variate geology and climate condition. In order to ensure homeland security, it is usually necessary for the relevant personnel to carry out routine inspections, which will consume a lot of manpower and resources. To this end, this paper proposes an aeronautical surveillance method based on deep learning, which uses drones to collect images from high altitude, and uses convolutional neural networks to classify and judge the collected images to monitor the scene. The purpose is to use artificial intelligence to replace the manual inspection by drones, thereby improving the efficiency of homeland security monitoring. To this end, this thesis establishes a database of top-down perspectives containing 10 different scenarios. Through the convolutional neural network model, the image features of different scenes are learned, so that the model can distinguish different scenes. In order to verify the feasibility of this method, this paper carried out experiments on 10 kinds of space-based perspective databases, and the results showed that the classification accuracy reached 97%. This shows that this method can meet the needs of security monitoring and provides ideas for intelligent monitoring.

Abstract:People detection is a challenge task in the field of computer vision. This paper aims to detect the pedestrians with high precision by only using the depth information provided by TOF(time-of-flight) camera. When the TOF camera is overhead, the human head, as a part of the human body, has very rich feature information and it can be unobstructed for a long time. In view of this, a people detection method, combing blob detection with water filling algorithm, is proposed. The proposed method first uses the mixture Gaussian background model to find the region of interest in the image; then it uses the water filling algorithm to filter out the candidate heads; at last, it combines with the prior condition to determine the real heads in the scene. In order to verify the effectiveness of the proposed algorithm, two kinds of real-time depth image datasets were tested. The result turns out that, compared with two other algorithms, the proposed method has better performance, and can achieve real-time and accurate people detection.

Abstract:In the aerospace electronics field, time-triggered ethernet (TTE) can act as an integrated network for carrying control commands and real-time data, with time-triggered (TT) communications for missions with high critical levels. TT communication task scheduling requires deepening design parameters such as topology configuration and path selection; however, in the early stage of design, it pays more attention to the application layer requirements for communication tasks, and it is necessary to plan TT communication tasks without deepening design parameters. This paper proposes a two-stage communication task planning method. Firstly, the communication task switching matrix is expanded into a communication task capacity matrix. Then, the BVN decomposition method is introduced and improved, and the latter is decomposed into time slices of non-conflicting communication task combinations, which is easy to form. A template that is arranged during subsequent scheduling. Case study shows that the planning method can reduce the communication task delay by 43% and compatible with the subsequent time schedule generation step.

Abstract:In this paper, the multi-hop amplify-and-forward (AF) relaying transmission from the source to its destination after the m-th hop is considered, and the frame structure construction process of the hybrid time-switching (TS) and power-splitting (PS) simultaneous wireless information and power transfer (SWIPT) protocol is given. Under the constraint of the total transmission power and throughput of each relay, the trade-off relationship between power transmission efficiency and information transmission performance is evaluated. A non-closed formal expression of double hybrid parameters is derived, and the maximum number of achieved hops under a given node throughput is calculated. The numerical simulation results show that, in order to expand network coverage and ensure energy efficiency, the two parameters can be dynamically adjusted by different relay hops to achieve the optimal SWIPT performance.

Abstract:Combined with the requirement of filter in engineering application, the design method of active low-pass filter based on CFA has been research. A typical current feedback operational amplifier has been selected. On the basis of the analysis of the transfer function of the VCVS filter circuit, a six-order Chebyshev active low-pass filter based on CFA has been designed. The circuit parameters have been determined according to the filter performance parameters and cut-off frequency. The software simulation results show that the cut-off frequency of the circuit is about 15 MHz, the pass band gain is 39.796 dB, the pass band fluctuation is 3.18 dB, the attenuation rate of the transition zone is -47.992 dB/frequency doubling, and the performance index of the filter is consistent with the theory. The datas indicate that the design method is effective and feasible, and can provide reference value for design of other active power filter.

Abstract:The field operation and maintenance of power communication network is very important for the stable and effective operation of power communication network and smart grid. In order to ensure the quality of operation and maintenance of power communication network and improve the operation and maintenance operation efficiency, this paper presents a field of power communication network. The operation and maintenance work order scheduling optimization method promotes the efficient implementation of on-site operation and maintenance operations. Aiming at the characteristics of onsite work order dispatching in power communication networks, combined with the characteristics of operation and maintenance personnel and operating resources, a mathematical model for on-site operation and maintenance work order scheduling under multi-resource constraints is described and established, and then a virus genetic algorithm is used to solve the problem. This paper provides an experimental evaluation of the proposed algorithm and verifies the effectiveness and feasibility of the proposed algorithm in field job maintenance scheduling under multi-resource constraints.

Abstract:In view of the complicated and variable environment of seismic exploration field, using traditional wired or single wireless technology to transmit data has the problems of low reliability, high cost and low efficiency. By analyzing the existing wireless technology, a kind of hybrid wireless data transmission scheme based on 4G cellular network and WiFi network was proposed. The solution prevents and relieves congestion through TCP Vegas and queue management. The test results show that the proposed hybrid wireless data transmission scheme operates reliably and steadily in the seismic exploration system, has high speed of data transmission. It can absorb large amounts of data flow in a short time and prevent congestion, provides technical support for the field seismic exploration process and has certain application prospect.

Abstract:With the continuous popularization and development of PEPS technology in the automotive market，passive entry and passive start are already available on more and more models. In addition to this, the welcome feature that has emerged is also being used more and more. The traditional intelligent key is not highly integrated and can not meet the market demand for new functions. In order to meet the needs of market development, adopt the real single-chip intelligent vehicle access control solution of NXP semiconductor, namely NCF29A1. It combines a keyless system (PKE), a remote-controlled RF transmitter, and an anti-theft lockout system, enabling a true single-chip solution that greatly simplifies the hardware design circuit. This design uses NCF29A1 as the main control chip to realize the software and hardware design of the smart key. In order to meet the latest design requirements of the market, functional aspects include RKE, PKE, PS, IMMO anti-theft, welcome function, etc. And in terms of cost and performance, due to the selection of the latest NCF29A1 single-chip solution, the static power consumption of the key is reduced and the service life of the key is extended. It has the characteristics of low cost, excellent performance and easy expansion.

Abstract:In order to solve the problem that existing internet of things routing schemes relying on specific link detection packages are vulnerable to interference, an internet of things routing scheme based on virtual network estimation is proposed. Firstly, the proposed scheme uses the network state vectors and the activity sharing to estimate the successful transmission rate of each link. Secondly, the traffic of the node is estimated according to the local traffic generated by the node, the inflow traffic of the neighbor node and the retransmission flow. Finally, the node that can increase the gateway traffic is selected as the next hop node, and the internet of things routing is established according to this principle. The simulation results show that the number of the data packets estimated by the proposed scheme and the simulation results are consistent, and the throughput of the proposed routing scheme is superior to that of the load-aware routing scheme. Therefore, the proposed routing scheme can be well used to find the effective transmission path of the internet of things, which has good theoretical research value and practical application value.