Abstract:Target tracking is to search the most similar parts to target in video sequences，which is an important research in computer vision．Focus on the moving target tracking in video sequences, a method based on meanshift for target tracking is proposed. First, the target area is determined and the target model is constructed in the tracking process. Then, the candidate target model in the Nth frame is calculated. Based on the Bhattacharyya similarity function, meanshift algorithm searches iteratively for the beat candidate area of the target model in the subsequent frames. Finally, the target tracking system based on meanshift algorithm is built with MATLAB, and through a series of experiments show that this method has a good tracking performance, and has low time complexity, which can meet the need of realtime processing.

Abstract:The cascade module of power electronic transfoemer (PET）has the problem of DC side voltage unbalance, which affects the stable operation of the system seriously. For power electronic transfoemer, the problem of DC side voltage unbalance in the cascaded H bridge rectifier is studied in this paper. The mathematical model of cascaded Hbridge rectifier is established, the reasons of voltage imbalance between cascaded Hbridge modules are analyzed, and the control strategy of voltage power balance is put forward, based on the reconstruction technique about modulation wave vector. By reconstructing the modulation wave vector, the balance of DC side voltage is achieved. The equal distribution of active power toward each H bridge is ensured, which makes the reactive power flowing through the H bridge to be allocated according to the requirement. Finally, the correctness and effectiveness of the method is verified by simulation in MATLAB/Simulink environment.

Abstract:To deal with the problem of severe distortion of the output waveform caused by the interference between the dual channel arbitrary waveform generator, this paper based on the theory of broad level power integrity and signal integrity theory, uses the target impedance method to design the decoupling capacitor network, to make the power’s impedance meets our design in the whole pass band, and in a further step, to make the power supply noise control in the acceptable range. Using SI9000 Polar to design a reasonable structure and line width, the signal line can meet the requirement of controllable impedance transmission line. Using the simulation software Cadence Signity 16.6 to simulate the system, and then tested on the hardware platform, the test results show that the interference between two channels’ signal is solved, the quality of the waveform signal has been greatly improved.

Abstract:The object studied is singlephase feedback type electronic load, the principle of Sandia frequency shift islanding detection(SFS) is analyzed in detail, nondetection zones are evaluated, and optimizing parameters of SFS algorithm. Meanwhile, SFS and Sandia voltage shift method (SVS) are combined to form a complex of islanding detection method with passive methods of over/under frequency and over/under voltage. Finally, the model of simulation are conducted in with the help of MATLAB/Simulink. The simulation results indicate that the system can be conducted without nondetection zones under special loads. The combination with SFS and SVS will significantly improve the detection efficiency,and it can carry islanding protection quickly and efficiently, and power quality is higher, the feasibility and the superiority of the scheme are verified.

Abstract:In order to realize a wideband RF source for cband and xband, an implement scheme of RF source was constructed based on the theory of PLL synthesizer. After introducing the synthesizer chips HMC983/984 and designing a wideband microstrip directional coupler needed in scheme, the parameters of LPF from simulation soft were obtained. By analyzing the design process of power and frequency resolution of RF source, the demands of soft control, filtering circuits, power supply design, input power of reference and feedback were mentioned, finally the design of the 5～10 GHz RF source was completed. The experiment revealed that the frequency error of the output signal was less than 0.001%, and the power flatness was not more than 4 dB, so the design achieved the expected specifications.

Abstract:This paper proposes an efficient buildin DC gain accuracy calibration system for digital oscilloscope, in order to substitute it for the conventional PC calibration system, which is complex and inefficient. Using Digital Oscilloscope instead of PC to control the oscilloscope calibrator directly, the system reduces the latency and speeds up its command stream and data stream. Benefiting from the tiny step programmable differential amplifier, the system improves the calibration accuracy. By calculating the calibration parameter according to sampling data directly, the system avoids the timeconsuming display processing. A highprecision internal calibrator is designed and the interfaces of it and various external calibrators are unified. The actual application results show that the system can meet the measurement need, at the same time, reduces the complexity and shorten the calibration time.

Abstract:Slope monitoring is a critical step to ensure the safety of excavation. However, conventional manual method using inclinometer is unable to fulfill realtime data acquisition and automated management because of its inefficiency and low monitoring frequency. So we use Internet of Things technology to develop a remote and automatic slope monitoring system based on electronic dip angle sensor. This paper presents the operating principle，constitution of this system and tests of its performance. According to the results, resolution, long term error and applicable accuracy of the sensor are 0.000002 rad, 0.0002 rad, and 0.0001 rad respectively. In the laboratory, the system has water repellency under the water pressure of 100 m and relative tolerance of 0.12 mm/m, which tentatively satisfies remote automation of excavation monitoring.

Abstract:A lownoise, broadband, high dynamicrange underwater acoustic receiver is designed to measure ocean ambient noise. First, new generation true RMStoDC chip AD8436 realizes realtime highprecision calculations of RMS value of the noise signal. Then, microprocessor is used to implement AGC by adjusting the gain code of programmable gain amplifier. Meanwhile, the system gain values are automatically recorded. The receiver has an excellent manmachine interactive interface, through which the gain values are transferred to the embedded host computer online and the system gain can also be set according to customer’s requirement. The experiment result shows that the equivalent input noise of the receiver is lower than 3 μVrms, the frequency band is 20 Hz~5.5 kHz, and the input dynamic range is larger than 68 dB. Besides, the designed receiver is precise, flexible and stable. Therefore, it can satisfy the demand of measurement and analysis of ocean ambient noise.

Abstract:Unmanned helicopter is becoming more and more popular in the field of agricultural plant protection, with the development of agricultural mechanization and modernization. And flight control technology is the core of unmanned helicopter. In view of the irregular shape of farmland, designing the flight route automatically and efficiently is one of the key technologies, which make sure the application of unmanned helicopter in the field of agriculture and improvement of commercial efficiency. With technical requirements of unmanned helicopter flight trajectory in agricultural plant field, the author of this paper researched irregular farmland identification and the optimal route design algorithm using the theory of graphics, and realized the corresponding function module and application software. The software has been proved in the engineering application, and achieved good application effect.

Abstract:The antishock ability of naval ship equipment is very important for ship vitality. For the reasons of cost and safety, the real test measurement cannot be processed frequently. The technology of numerical simulation provides a new method for ship equipment evaluation. The finite element analysis technology based on acousticstructure interaction method was used to simulate the shock response of a small floating shock platform(FSP) numerically. Then, the realtime explosion test validated the peak acceleration and shock response spectrum compared to the simulated result. The results showed that numerical simulation can provide the exact input for ship equipments and predict the shock environment of the FSP accurately. The method can be extended to medium and large FSP.

Abstract:In the algorithms of change detection of remote sensing image based on semisupervised SVM, PTSVM algorithm uses paired labeling rule that once marks only one pair of unlabeled samples to label unlabeled samples, which achieves good results in the change detection of remote sensing image and to some extent, improves the detection accuracy. But PTSVM algorithm uses only spectral information of samples. Sample characteristics information includes not only the spectral information, but also spatial information. Spatial information as one of the basic characteristics of the sample is equally important, so this paper proposes the improved PTSVM algorithm combined spatial information of samples with spectral information of samples in change detection for remote sensing images. Through the experimental results analysis, the method has achieved good results in change detection of remote sensing image, and further improves the change detection accuracy.

Abstract:In order to realize the edge extraction of color images, and to ensure that the algorithm has better stability.The article used the multiscale Gabor filter method to extract the edge of the color image and contour, the Gabor filter has three scales and sixteen directions.The first, changes the color image into the gray image, the imaginary part of multiscale Gabor filter is utilized to obtain the change information of gray image.The second, Through the nonmaxima suppression,and then through the high and low threshold to extract the edge pixels and its candidate edge pixels.The last, through the local edge connection to obtain edge contour line. And the performance of this algorithm is compared with the commonly used edge detection algorithm.This experimental conclusion states: this algorithm can obtain high positioning accuracy, and also has good noise robustness. Compared with a series of algorithms, such as Roberts, this method has better detection effect and better stability.

Abstract:The thesis developed a set of Photovoltaic solar power grid data acquisition system which includes functions of data acquisition,analysis&process and measurement correction.In order to solve the measurement error caused by zero drift and nonlinear characteristics of components, thesis proposed a kind of data calibration algorithm based on sector least square method.It set up the standard values of photovoltaic date acquisition system by measurement standard table, do measurement calibration for system by Piecewise least squares fitting method, and decide whether system meets design requirements by comparing Standard to measure value and calibration value. The experimental results indicate that Piecewise least squares fitting method can compensate the measurement error of the system effectively, The measurement error has been reduced 89.6% after using Gridconnected PV data acquisition system and calibration algorithm compared with metrical date without calibration, measurement accuracy been improved effectively.

Abstract:Radio Frequency fingerprinting is the transmitters identification in wireless communication process, applying in wireless security, whose difficulty is the effective feature extraction. The feature extraction approaches for RF fingerprinting can broadly be divided into transient and steadystate analysis. Considering the difference of transient waveforms, we use transient intensity as the fingerprint feature to identity transmitters, which is defined as the ratio of signals’ mean power and peak magnitude. The classification performance of notebook wireless network adapts in different models and USB wireless network adapts in different series have been evaluated from experimental simulation, combined with features of the magnitude of HilbertHuang Transform and the Short Time Fourier Transform in timefrequency domain. It is demonstrated that the feature of transient intensity has some advantages, such as high accuracy and short time of classification.

Abstract:For the restrictions that the fixed camera cannot automatically track the moving target, a rotatable camera system was designed based on the steering engine, in order to position and track the moving face. The Adaboost algorithm was used to detect and track the face. The face detectionpositioning– tracking system was designed under the development environment of Visual studio 2010 with the computer vision class library OpenCV and the graphical interface development framework Qt. The test results show that the accuracy rate for tracing face is 100% in the bright environment, and 95% in the dim environment. And it is also effective to tract the partially occluded face. This system can also be applied for security and other fields.

Abstract:Vision navigation has become one of the main navigation methods of micro air vehicles. In order to provide a platform for the research of visual navigation technology, a digital image realtime acquisition and transmission scheme is designed. The IEEE 1394b bus is used as the transmission protocol. FPGA, as the control core, generates the timing control logic of the image sensor, FIFO buffer module and 1394b protocol link layer IP core. The image data is packaged into the 1394b format after the FIFO buffer, and then transmitted to the computer with a 1394b acquisition board through the optical fiber after signal conversation. The C++ Visual is used to process the received data, and the display and memory functions of the images are realized. Test results show that the average transmission rate of the system is 123.264 Mb/s, which could meet realtime requirements.

Abstract:Image feature detection has been developed rapidly in the computer vision, and the SURF feature description can be very stable and fast. RANSAC can estimate the parameters of the model under the condition that the inliers is more than 50%, and it plays a key role in the feature points matching. The surf descriptor of image feature points of detection and description, and then applying the cross matching strategy effectively eliminate wrong matching points, then the use of RANSAC algorithm to estimate the model. Finally, using the linear weighted method for image fusion. This method can be used to match images in low time complexity with the the SURF feature detector and descriptor and RANSAC algorithm.

Abstract:ARM processor and μC/OSⅡ operating system as the core of embedded technology has been widely applied in low cost and micro realtime system. In the paper, the research object of micro unmanned helicopter flight control system using LPC2468 micro controller, application soft design based on the μC/OSⅡ operating system. For multihardware interrupt and μC/OSⅡ many task management scheduling mechanism combing the running of flight control software. To meet the requirements of the system stability and reliability of the engineering application, launches the corresponding research of μC/OSⅡ system transplantation driver development and flight control software structure design. Finally, we tested the whole system.

Abstract:To take full advantages of LXI instruments based on LAN and allow users to control the instrument through web interface completely, a scheme to extend the capability of LXI web interface was proposed. Bclass LXI DAS is taken as the design target in the scheme and deep design to the HTML framework is implemented. Many extra functions, including realtime curve, equipment control, status display, database uploading are added to the HTML pages besides the fundamental functions; transporting LwIP protocol realizes a HTTP server in embedded chip without OS; communication based on AJAX solves key problems of dynamic HTML page and smoothing data refreshing. Finally a B/Sbased LXI DAS is built by. As for implementation, test result shows that the web interface improves interactivity and functionality of traditional ones and has better advantage in compatibility and light architecture with the B/S framework.

Abstract:In many fields of production and life, the demand of environmental detection is increasing, but there are many spaces that are not suitable for human activities or exist certain risks. For the detection operation of the above special circumstances, it need to design a number of intelligent detection car to complete. The design uses the upper and lower monitor structure. Using a STM32 as the core, the lower monitor realizes four control functions, which are the car motion control, environment detection, automatic obstacle avoidance, and WiFi communication with the upper monitor. The combinational characteristics of ultrasonic and infrared sensors are used to detect obstacles and improve the stability of obstacle avoidance. In the laboratory environment, using the interface developed by VC++ on the PC to set up running and control parameters of the car, the test of the design meets the expected design requirements.

Abstract:Aiming at the existing smart home technology to design the more flexible assembly and convenient handling system. Basing on the wireless interconnection mobile terminals, and cloud computing technology, using the intelligent image recognition technology for robot localization. Experimental results show that the system has achieved the corresponding function, on mobile terminal through cross screen and voice to dialogue with the robot, so as to expand the application areas of system.

Abstract:Since some shortconmings as timeconsuming, poor accuracy and difficult expansion, traditional manual testing method has bottlenecked the rapid development of radar testing technology,so we have to build new ones urgently. Based on standard system bus and specially designed adapter, the generalpurpose automatic test system can test diversified modules or plugins of many subsystems. After recognise the adapter ID, automatic test system execute corresponding testing schema automatically. Testing management system can analyse and diagnose the fault of equipment under test (EUT), trace back to fault causes from fault phenomena. Then, it put forward fault diagnoses method, finally implement fault localization. Through practical application, it has been proved that the system has good versatility, high degree of automation, really implement the instruments parameters automatically set, automatic data acquistion, automatic storage of the test results and many other functions. Furthermore, the radar generalpurpose automatic test system show the construction of perfect function, stable performance.The system played an important role on R&D process and Maintenance of an exported radar.

Abstract:In order to satisfy the requirements of smart antenna beamforming, an adjustable powersplitter and phaseshifter microstrip circuit has been developed for radiation pattern measurement of smart antenna in microwave anechoic. The circuit is composed of Wilkinson power divider, πtype resistance attenuator, loaded line phase shifter and cascade of a coaxial transmission line. The onetofour powerdivider and phaseshifter microstrip circuit has been realized with power ratio 1∶2∶2∶1 and sequence phase difference 105 degrees in TDLTE F band. Simulation software of HFSS was used to optimize the design of the circuit. And the circuit was fabricated and measured. The measured results show that the input VSWR is less than 1.2 with the amplitude error less than 0.5 dB and the phase error less than 3°. The structure of the circuit is of low cost, and the distribution of the amplitude and phase is easy to adjust. It can meet the needs of the testing application.

Abstract:In view of measurement requirements in the underwater explosion test such as freespace pressure, wall pressure, acceleration, etc., putting forward the design train of thought and test methods based on the distributed measurement technique. The method fully considers measuring multichannel, high realtime demand, high reliability demand in the underwater explosion test. By adopting distributed measurement way and CAN communications in distributed explosion measurement system, the data acquisition, transmission, and fault upload of measurement unit are managed and controlled. So the system reliability is improved, and measurement data collection is ensured. In laboratory, the reliability of trigger acquisition is tested with two simulated trigger signals. Experiments show that the system can be triggered reliably with any one trigger signal. This system is successfully applied to explosion test, it is more flexible, more convenient, and more reliable than other measuring equipments.

Abstract:Urine test instrument is an important medical diagnostic equipment, however the traditional instrument urine has been designed with great limitations. In order to aviod the disadvantage of large volume and high cost, this paper designed a portable wireless urine test instrument based on the principle of the capacitive sensor. This system take capacitive sensor TouchSenser as the detecting element and using Pcap01 ACAM to detect the capacitance change of every unit. The controller of this system was STM32L152, an 32bit microcontroller of STMicroelectronics, with low power consumption. Low power Bluetooth chip Da14580 of Dialog Semiconductor was used to wireless communicate. In order to obtain accurate capacitance value, proposes a data processing algorithm based on Pauta criterion. The experimental results show that the urine test instrument has the characteristics like high precision, flexibility and so on.

Abstract:IEEE1394b is a highspeed serial bus, with strong realtime, high reliability and wide application. Optical transmission technology has characteristics of strong anti interference ability and long distance transmission. This paper designs and implements a data optical transceiver module based on the combination of both advantages. Applying FPGA as the core controller, this module builds PCI bus controller with the technology of system on chip to achieve the control of IEEE 1394b link layer interface, realizes the DMA driver development of embedded system based on IEEE1394b’s isochronous transmission mode and achieves the conversion circuit from electricity to light of IEEE1394b physical layer utilizing circuit simulation based on PSpice. Meanwhile the implementation of the protocol mapping from IEEE1394b to fiber channel realizes the interconnection between IEEE1394b and fiber channel and also works out the limitation of IEEE1394b bus network topology. The module is able to adapt the embedded, highspeed, longdistance and realtime demands of data acquisition systems.

Abstract:In allusion to the photoelectric signal detection or data acquisition under the condition of the weak photoelectric signal or weak signal to noise ratio, the modulation/demodulation circuit based on the autocorrelation detection principle is proposed. It is aimed at the photoelectric intensity adjustment of the modulation sensor and the detection of weak signal.The circuit uses pseudo random code and optical fibre sensor to modulate the weak signal and detects the weak signal according to the output light intensity. Meanwhile, the numerical simulation for the sensing circuit with strong noise is carried out. According to the simulation results, photoelectric signal detection and data acquisition based on the weak signal to noise ratio conditions are realized effectively.

Abstract:The design in this paper aims to make periodical deflection with FPGA controlling galvanometer to achieve laser linear scanning, and to replace digital oscilloscope with data acquisition card to collect photoacoustic signals. DAQ card based on VC has flexible control of the data acquisition of the photoacoustic signal, the system timing is under the control of FPGA. The experiment has proved the feasibility of deflected scanning of galvanometer and the data acquisition card. This scheme can efficiently improve the current situation that the existing photoacoustic imaging systems in labs can only achieve linear scanning with manual adjustment of stepping motor, it is able to collect the available photoacoustic signal in the light of its own demands, and it also provides basis for the implementation of integrated photoacoustic imaging system combined with the acoustical lens in post production.

Abstract:Duffing oscillator is extremely sensitive to the periodic signal and has strong immunity to noise. So it is used for the detection of weak periodic signal in strong noise background and the measurement of its parameters. In order to further improve its detection performance, a new method of Duffing oscillator weak signal detection based on signal preprocessing is proposed and is proved in theory. The new method firstly processes the signal by segmentation, stacking, extension then sends the processed signal to Duffing oscillator to detect. Simulation results show that the proposed method can obtain a large SNR gain, when the segmentation number is three, the lower limit of detection SNR reduces about 2dB, when the number of segmentation is five, the lower limit of detection SNR reduces about 3dB.

Abstract:Mud pulse signal communication is the main communication way of wireless logging with drilling system, but the mud channel attenuation is large, and the channel noise is complex. A joint coding method which is suitable for the mud pulse signal was proposed, after analyzing the mud channel characteristic and noise source,in addition to realizing lossless compression it can correct unexpected errors and random errors as well,the coding method guarantees the transmission efficiency and at the same time reduces the bit error rate, and will not increase the complexity of the equipment. Finally based on the field logging data, it shows that the maximum compression ratio of LZW is 3:1, and through the simulation experiment, the result proves its antinoise effect, logging data can be well reconstructed, which verifies the effectiveness of the joint coding method.

Abstract:This paper introduces the basic constitution and the engineering application research status of the bridge strain data acquisition system, from two aspects of hardware circuit and software program to describe the design scheme of the strain data acquisition system, the key technologies of the hardware design of the system is mainly studied. The power management system based on TP4056 and STC12C2052AD is proposed. A new bridge circuit wiring method based on the Wheatstone bridge is designed to detect the strain capacity in significant nodes of the bridge. Aiming at the problem that the system measurement accuracy is reduced when the strain capacity is to maximum but the actual output voltage is very small, signal processing circuit is designed. Experimental tests conducted on bridge show that the proposed system can improve the measurement accuracy and operate steady, verified the correctness and feasibility of the proposed method.

Abstract:School of Automation Science and Electrical Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100191, China

Abstract:Usually the enterprise decision analysis system needs to deal with the key business information. These operations are automaticly deal with lots of complex information without user interaction. In order to solve the problem of low efficiency of batch data operation, in this paper, based on indepth research and analysis on the Spring Batch framework, we use SpringBatch framework, open source job scheduling Quartz and relational database MySQL and non relational database Cassandra to design and implement the decision analysis system of efficient batch processing. At the same time, this paper also carry out the performance test of the system, test results show that the decision analysis system which used the SpringBatch framework to implement is more efficient in batch data processing.

Abstract:In view of the problem that the existing APF(active power filter) has less data storage, weak data processing ability and poor ability of remote monitoring, the signal acquisition, processing, transmission, display and so on of the APF in the operation are studied. The design method of online monitoring system is summarized. The realtime monitoring system for APF operation is designed. This system adopts the lowpower STM32F103RBT6 chip as the signal collection and processing controller, using STM32 development board peripheral function module for data transmission, storage, and using the advanced standard communication interface on development board to realize RS485 remote communication. Thus the problems that APF data storage capacity is small and remote monitoring ability is weak are fundamentally overcome. The experimental simulation results show that this system has greatly strengthened the ability of APF data acquisition and processing, significantly enhances the data storage and remote monitoring effect is good. The system operation is simple and has low cost, thus it has good application and popularization value.

Abstract:The practical application of fault diagnosis method is limited because of the lack of accurate failure mode analysis, and in order to solve this problem, a hierarchical analysis framework for failure mode and effect analysis (FMEA) is proposed in this paper. This method divides the FMEA analysis into three levels: the device level, the board level and system level. As to the device level, accelerated stress test method is proposed to analyze the temporal deterministic effect. As to the board level and system level FMEA, a limit test platform is developed. The specification boundary for electronics system can be acquired using this platform, as well as the test method and fault mode. Using the method proposed in this paper, the failure mode of whole electronic system can be acquired, and provide practical application basis for fault diagnosis.

Abstract:In order to solve low recognition rate and poor robustness in pipe defect recognition based on ultrasonic guided wave, principal component analysis (PCA) is used to optimize the feature of pipe defect echo signals. First, a few characteristic parameters in domain of time and timefrequency were extracted by means of dealing with the ultrasonic guided echo signals of the pipe defect to construct a multifeature vector. The multifeature vector dimension is then reduced using principal component analysis. The fusion feature is generated by extracting the principal component whose cumulative contribution rate is about 89%. Finally, BP neural network is used to train and recognize fusion feature. This method can effectively recognize the pipe defect, and has higher recognition rates than that of the multifeature vector.

Abstract:According to the frequency domain energy distribution differences of bearing vibration signal in the different failure modes, rolling bearing fault pattern recognition technology based on the orthogonal wavelet packet decomposition and BP neural network is proposed. The orthogonal three layer wavelet packet decomposition for rolling bearing vibration signal is carried out to get the third layer wavelet packet decomposition coefficients from low frequency to high frequency，then the different frequency band signal are reconstructed respectively to extract energy features by means of wavelet packet decomposition coefficients. Using the energy feature vector of different frequency band as the model input of the BP neural network model，a large number of samples are trained to get the network pattern recognition model for different bearing fault，then use several groups of test data are used to verify the BP network models to discrimination the type of rolling bearings fault. The test results proved that the method integrated the Wavelet packet decomposition with BP neural network can identify the fault of rolling bearings more accurately.

Abstract:With the development of the Internet of things, architectural design and construction stages for the application of Internet of things has become indispensable.In the background of the project of Shenyang Shang Tai Department Store, based on the steel wire strain sensor and angle sensor, we studied a construction monitoring system and the analysis of monitoring data and solved the problem of data commission and acceptance.Firstly, according to the site situation we made the rational arrangement of measuring points in the vertical deflection and stress. According to the change of the structure response, after the processing of monitoring data, it can realize the reasonable control of the construction steps, so as to achieve the purpose of safe construction.

Abstract:To ensure the soundness of spare parts and to solve performance degradation or failure caused by prolonged， we focused on the characteristics of some aircraft display and control system equipment， designed the display and control unit is powered aging system. The system used automated test， virtual instruments， artificial intelligence and signal designoriented technology， treated the computer as the core， GPIB instrument as the base， multiple bus interface as the link， built the aging system which has advanced technology， high reliability， good versatility and easy to operate. The results show that use of the system which with high economic and military benefits can improve the integrity of aviation materials effectively.