Abstract:The high voltage arm resistance is a key factor to test accuracy when using a resistive divider as a voltage converter to measure high voltage which contain static and dynamic step, and the high measurement accuracy of the signal is an important indicator of the highvoltage test. This paper proposed the lowrated power resistor formed a divider to improve the accuracy of voltage test, and analyzing temperature changes under different cooling mode and different insulating medium. The issue of high temperature when selecting a low resistance be solved by reducing the initial temperature of resistance through active cooling. The experimental results show that the voltage measurement accuracy optimized effectively by using the lowrated power resistor which solved the problem of high temperature.

Abstract:Colpitts chaotic oscillation circuit is composed of a triode and other linear components. It has a very extensive range of research and application. Colpitts chaotic oscillation circuit can generate a variety of chaotic signals, which can be applied to wireless transmission, communication encryption, signal detection and other fields. In this paper, two types of Colpitts chaotic oscillator circuits are introduced, and their circuit models are analyzed. At the same time, the chaotic signal generated by them is compared and analyzed, and the chaotic signals are used as the excitation signal of the wireless transmission system. In addition, the complementary cumulative distribution function curves show that the optimal Colpitts chaotic oscillation circuit has a preferable conversion efficiency of the rectifier circuit in the wireless power transmission system. Finally, the detailed chart of conversion efficiency of these circuits has been demonstrated.

Abstract:The performance of sensor is affected by the shape and the geometric parameters of coil. In order to optimize the detection performance of sensor, finite element model was established in the COMSOL Multiphysics. Simulation analysis on the structural optimization of sensor was conducted, and verified by the experiments. The biorthogonal rectangular sensor was found to have higher detection sensitivity comparing with the single orthogonal rectangular sensor. Otherwise, the effects of thickness, external shape coefficient, internal shape coefficient, excitation current, external shape proportionality coefficient of the auxiliary coil on detection sensitivity of sensor were investigated under the case of a fixed coil turn density. The conclusions from the study provide a reference for the determining of the coil parameters and the improvement of the sensor performance.

Abstract:An indoor navigation system based on the RTOF (round time of flight) of Chirp signal is designed and implemented, which is used to locate and track multiple targets in a complex building interior. Time division multiplexing method to allow more tag positioning simultaneously, SDSTWR (symmetrical doublesided twoway ranging) algorithm is realized between mobile tag and anchor node, then tag sends the result to the positioning base station, and through to the computing center. Computing center uses the improved kalman filtering algorithm to reduce the NLOS error and the weighted correction three points localization algorithm to calculate the mobile tag location information, which is stored in the location server finally. The client is able to access to the server to check the result of appointed tag. The experiments show that, within certain complex floor structures, the precision can reach 2 m, meet the demand if indoor navigation accuracy. The system has also realized refresh time optimization with tag number, with flexible and deployable.

Abstract:To carry out major energy parameters research for the transient electromagnetic excitation coil,according to the magnetic induction vector superposition principle, the design of several simple structure having focusing properties of the excitation coil structure, focusing effect by comparison, mutual size and the difficulty of making merit considering the electRectangle surface arrays, the response surface method focusing coil having a magnetic characteristic parameter optimization. Using electromagnetic simulation software simulation, comparing with the traditional singlecoil, the excitation energy of the magnetic field coil so that the main focus in a radius of less than 0.3 m, and the magnetic flux density within the target area increased 33 percent, to lay the foundation for further practical application, change a rectangular array overlap area is magnetically different depths of focus, good focus to improve the transient electromagnetic method of partial defect detection rate, to achieve accurate detection of parallel and overlapping metal pipe buried the remaining wall thickness.

Abstract:A current perturbation twophase maximum power point tracking(MPPT) control method is proposed, which divides MPPT into three regions by the combination of PV and IV curves. In current and voltage source regions, which adjusts the working point current of the PV array near the maximum power point(MPP) by shortcurrent method. Later current perturbation and observation(P&O) method is adopted to regulate the PV array operating point to achieve the MPP accurately. The shortcurrent method is introduced to determine the upper and lower boundary of the threshold function under different light intensities. The linear equivalent circuit model of PV array is established, analyzing its amplitude frequency and phase frequency characteristics, stability of the closed loop parameters are obtained. The proposed method has been applied to 115 V/400 Hz standalone PV power generation system. The simulation and experiment of system show that the system runs stably and maintains a good working condition. The results prove the proposed method is quite more feasible and correct.

Abstract:The processes of generation, reception of ultra acoustic wave of EMAT and principle of detecting defect in conductive material were presented in this paper. Then a FEA model of 2D EMAT was set up to detect the internal defects in conductive material based on the electromagnetics theory and finite element method. The accuracy of FEA model was verified by refining mesh elements and result comparison between theoretical calculation and simulation. In the last, simulation result comparisons indicate that the 2D EMAT model can be applied to detect internal defects in aluminum and steel plates, and compared to the steel plate, detecting effect for aluminum plates is more efficient.

Abstract:To estimate symbol rate of phaseshift keying（PSK）signals in high precision rapidly, a new algorithm is proposed after an analysis of the delaymultiply circuit. The new algorithm estimates symbol rate roughly by estimating the bandwidth of signal. Using with the rough estimation, the algorithm can estimate the symbol rate in high precision by the delaymultiply circuit. The validity is verified by computer simulations. This method is not only applicable to the symbol rate estimation of baseband signals, but also to the symbol rate estimation of modulated signals. The estimation accuracy of the proposed algorithm can be improved by increasing the number of sampling data when the sampling rate is fixed.

Abstract:In this paper, the author put forward a double model to solve the method of electrical impedance imaging system.In the treatment of the forward problem, provides a fine cylinder model; In the treatment of the inverse problem, provides a relatively rough 3d model of cylinder.The two models is through the corresponding mapping formula for finite element unit and deficient detailed finite element unit conversion.To find the mapping system model transformation, this paper puts forward the dual model is established by sparse matrix P which is the mapping relationship.Finally using the reconstruction algorithm of electrical impedance imaging, proves the double model system.Through the computer simulation and using modified Laplace GuassNewton reconstruction algorithm can get impedance reconstruction images clearly.

Abstract:Acoustic method to detect wind vane delaminating damage is a kind of feasible and relatively easy to implement, the method of acoustic signal endpoint detection is important link in acoustic resonance method to detect. In order to improve the adaptability and robustness of endpoint detection, wavelet transform and the MFCC parameters extraction are studied. Based on these research, a new parameter, DWTMFCC, is extracted. And using the SVM to audio endpoint detection. The experimental results show that, compared with the traditional wavelet and MFCC parameters, in the same noise environment, DWTMFCC has a higher rate of endpoint detection.

Abstract:For reducing a fixed threshold binarization method’s drawback and the serious Inadequate and Interference after binarization handling,meanwhile the traditional DSP and other processors in highspeed image processing in realtime poor is not good enough, proposing that using FPGA / Nios II processor and the improved adaptive threshold Sobel algorithm for image binarization, morphological processing again. The whole system implementation includes the original image capture, color format conversion, gradation processing, edge detection and median filtering using the weighted average method and adaptive threshold image binarization, and finally by using morphological methods to further deal with the binary image, to achieve a more efficient extraction of contour, and through VGA interface display. Experimental results show that the system is high efficient, fast, stable and reliable.

Abstract:Abnormal crowd behavior detection is a highlv focused research area of the intelligent monitoring.The paper mainly aims at studying how to extract spatiotemporal characteristics of dense crowd video,and how to improve the efficiency of anomaly detection.Combining with human visual system(HVS),we proposed a novel method based on the analysis of the quaternion Fourier transform which is a fusion of spatiotemporal characteristics in order to extract features of dense crowd scene.It is proved by the experiment that the proposed method can describe the dense crowd scene from different aspects and achieve good effect of anomaly detection as well.

Abstract:In the light of the background of the complex situation, the image acquired by the image has fuzziness and color difference, through the white balance deviation compensation, improve the imaging results. In the traditional method, the contour feature fusion method is used to compensate the white balance in the complex illumination. When the image pixel is lower, the color difference compensation is not good. A new method of white balance offset compensation based on wavelet packet decomposition is proposed. Firstly, the image of the complex illumination is collected and the image is described. The original image is processed by noise reduction. The color difference of the image is analyzed and extracted by wavelet packet decomposition method. The simulation results show that the image processing method is used to compensate for the White Balance errors, which can effectively balance the image color, improve the image of the image, the performance of the details of the image is more powerful, the peak signal noise is relatively high, and the performance is superior.

Abstract:Hyperspectral data is becoming increasingly popular and widely used. Accurate classification of the high ground objects is one of the core application of hyperspectral remote sensing technology. Extracting feature from hyperspectral data is an effective method for classification. Deep learning is the new areas of machine learning research. It has multilayer perceptron structure so that it can learn to portray a more essential characteristic, and have better results in the field of image classification and visualization. DBN is a normal model of deep learning network. A hyperspectral image classification model based on DBN is constructed by using high dimensional feature of hyperspectral data and combining the spatial structure of hyperspectral data. Experiment shows that high spectral image classification based on DBN can get better classification results.

Abstract:For geostationary meteorological satellite application, landmarks registration is the first and most important step. The landmark registration results in high resolution satellite image show as edges which are easy easily to influenced by clouds, noise and other edge interference,. In this paper we propose a method based on geometric information, using shoreline in high resolution satellite image and standard image of landmarks based on GSHHS to get accurate matching points through geometric similarity registration.

Abstract:The jitter of remote sensor during exercise will cause the image position shift. To settle this problem, a realtime image correction algorithm is proposed. However, the design of algorithm by using HDL has great difficulty and it leads to long development cycle. Therefore, the design of algorithm is achieved by adopting C language. Then the abstract C algorithm is translated to RLT code by means of Calypto’s Catapult C Synthesis tools. Furthermore, a cosimulation test of C/C++ and RLT is carried out in Catapult C Synthesis tools. It’s also verified in the platform of XC5VLX110T. The results of Simulation test and hardware verification show that the algorithm designed by applying Catapult C Synthesis tools can meet the design requirements both in timing and performance. And it can correct the shifted image in realtime.

Abstract:The method based on dark channel prior will cause excessive noise and halo phenomenon in the region of sky.To solve this problem, a method of adjusting the transmission rate of the sky region is proposed based on the credibility of the sky. To obtain the credibility coefficient of the corresponding position of the fog image,Changing the adjustment range of transmissivity adaptively,and using characteristic of the quadratic function to change the map of the credibility coefficient,then the hazefree image can be recovered by the atmosphere scattering model. A lot of experimental results show that the recovered image by the proposed method is clear and natural,especially in the sky region.Retaining the degree of haze remove in dense fog area and suppressing the noise and halo phenomenon in the region of sky. The improved method proposed in this paper can obtain better effect than the method based on dark channel prior in the processing of haze removal.

Abstract:Hyperspectral image classification has become one of important hyperspectral applications, but how to get good classification results in the case of small sample size is still an open issue and attracts many research attentions. In recent year, deep learning has been used in the context of remote sensing image analysis. In this paper, we propose a new hyperspectral image classification method based on EMAPs (extended multiattribute profile) and polynomial networks (PN). Firstly, EMAPs can extract multilevel structures of morphological features by a series of attribute filters, which integrate the spatial and spectral information of remote sensing data. Then, the spatiospectral features are fed as the input to the deep PN composed of multilayer feed forward structure. PN decreases the training error layerbylayer in the sense to obtain good classification results. Classification experimental results on different hyperspectral image sets demonstrate that the proposed method outperforms other methods.

Abstract:In the traditional image retrieval methods based on wavelet transform, the wavelet transform and the importance of the different color components of HSV color space are not considered. For this question, this paper proposes an new image retrieval method using wavelet transform in HSV color space. Firstly, each image would be transformed from RGB color space to HSV color space. Then, each color component(H,S,V) of the image is performed by wavelet transform to extract the texture features of the image, and the feature vector of the image is also obtained. Finally, calculating the similarity between the retrieved image and each image in database by assigning the weights of three color components reasonably with the importance, and get the retrieval results. The results of experiments show that the algorithm given in this paper can get better retrieval performance.

Abstract:In order to improve the control and performance ability of GPS display control system, in the electrooptical tracking device. Based on the previous equipment, increase the touch screen display terminal and new circuit structure. The operation interface is simple, beautiful, providing a good interface for the operator. Based on the structure of FPGA+DSP, The system control precision, convenient, and its realtime processing ability is strong. In the engineering application, the system is stable, easy to operate, and communication with other systems works well, which achieving a good GPS navigation, positioning and other functions

Abstract:In this paper, a complete set of vibration meter design including ARMbased hardware platform and signal processing algorithm is proposed to achieve vibration signal acquisition and transmission. This design is based on the actual situation that the pump maybe loose due to vibration caused by longterm running. The power part has over voltage protection function, signal processing algorithm sensor with high sensitivity, fast transfer rates and other characteristics, and the algorithm achieves less error ensuring efficiency. The meter is proved to be of high stability and reliability after a large number of laboratory tests and field trials.

Abstract:A design of the portable oil wells environment monitoring and gas detection system based on STC12C5A60S2 microcontroller，NRF24L01 wireless transmission module and a wireless AV module is proposed to improve Environmental monitoring efforts and the safety production of oil well, which uses gas sensors and the STC12C5A60S2 chip A/D conversion function for data collection, getting the realtime environmentally images captured by the camera with the PTZ.The acquired data and realtime images are transferred to the handheld terminal display by NRF24L01 wireless transmission module and a wireless AV module, and experimental results show that the device can realtime returns environmental picture and the accuracy of the gas concentration. The error is allowed. The use of the device is good for enhancing the safety of detecting person and detection efficiency, and ensuring the detection accuracy, which has good practicability.

Abstract:Human joint motion measurement means a lot in judicial expertise, rehabilitation medicine and other fields. This paper designs and realizes a kind of joint motion measurement system based on euler angle. The System get marker location information through optical positioning device, then compute angles using algorithm of rotation matrix and euler angle inverse solution.System has realized the accurate, realtime motion measurement and it suit to the motion measurement of neck, waist, shoulder, elbow, wrist, hip, knee and ankle. Accuracy verification experiment show that the system precision can reach within 0.3 degrees.

Abstract:Teaching playback is the major way of robot path tracking. Its working principle decide the complex degree of robot working. With the technology of human motion tracking, we can simplified robot teaching program and improve the safety of working environment. This article focus on the human motion tracking based on the technology of MEMS. With the 9axis inertial sensor, which include an accelerometer, a gyroscope and a magnetometer, and the method of complementary data fusion, the data accuracy of hands will improved. The results of linear path motion and space continuous path motion experiment show that the date calculated by this method has the high accuracy, can be used in robot teaching playback.

Abstract:Cable communication often brings some problems such as difficulty in wiring, equipment flexibility is not high in the process of industrial production, And the range of the existing wireless intelligent temperature transmitter transmits data is very close，at the same time past temperature transmitter’s range adjustment used to be changed resistance, steps are tedious，it brings much inconvenience to debug In order to solve these problems, this paper combines temperature transmitter with 3G technology and programmable gain amplifier. Modifying software parameters can easily adjust range. This paper introduces a kind of intelligent temperature transmitter which uses " programmable gain amplifier +A/D + microprocessor+ D/A" model, realizing the design of wireless intelligent temperature transmitter. The temperature transmitter has many functions, such as its range can be adjusted, 3G wireless communication, LCD 1602 realtime display and so on. The whole circuit design is simple, high precision and good stability, having a certain practical value and application prospect.

Abstract:A man machine interactive system, which is based on USART of STM32 and applied to new automatic weather station of DZZ12, is designed. Through this interactive system, the user can directly and conveniently set parameters or view data in the installation and maintenance for the new automatic weather station. This design includes hardware circuit design, user UI design and embedded software design. The design flow of user UI and the key points of the USART interrupt function are described emphatically. It proves that the system is stable and reliable after testing and business operation for one year in Guangdong Province.

Abstract:Some problems that lowprecision, high power consumption and long operation time are still existed in ultrasonic heat meter on the current market. So the ultrasonic heat meter based on STM32L152 and TDCGP22 is developed. Flow, temperature and heat are measured by ultrasonic timedifference method for flow measurement and capacitor’s chargedischarge principle for temperature measurement. The designed heat meter includes flow measurement, temperature measurement, communication modules and interactive modules. Hardware circuit design and software design of the heat meter are described in detail in this paper. The experiment results show that the flowmeasurement precision error is within 1% and it can work 9 years consistently with one 19 000 mAh battery supply. The ultrasonic heat meter with battery supply has the advantages of highprecision and lowpower consumption. It has broad prospect of applications.

Abstract:Sensor observation service (SOS) is one of the core services of the sensor web enablement (SWE), which is used to manage the data of multi source sensor observation, and to provide data services to end users. Open geospatial consortium (OGC) developed a standard for inserting observation data into SOS and obtaining data from SOS, but could not handle the heterogeneous sensors using different access mode and different data transmission protocol adaptively. When manage the data of multisource sensor by SOS, system must resolve the observation data from sensor, and convert it to the data format under SOS specification. In this paper, we design a new technology scheme of data access to SOS for heterogeneous sensor, discussed the implementation process of the scheme from the aspects of sensor registration, access network selection, data receiving and parsing, insert document generation and data insertion. Take wearable heart rate monitoring sensor as an example, we realized the SOS management of heart rate monitoring sensor monitoring data. The result shows that the scheme is feasible, and it provides a basis for the access to SOS of heterogeneous sensors.

Abstract:Time synchronization is an important theoretical research in wireless sensor networks. The users can know accurately know the information in the monitoring area, only when the sensors have a consensus clock. An innovative distributed time synchronization protocol, called GCTS(group consensus time synchronization), was proposed for largescale wireless sensor networks. Each sensor node collects the clock information of the neighbors. The sensor update the clock information according to the result of calculation using group consensus protocol. The advantage of the protocol is fully distributed and it has simple calculation, fast convergence rate and low energy consumption. At the same time, the proof for the convergence of the proposed protocol is carried out using Lyapunov stability theory and graph theory. Finally, the proposed protocol for largescale wireless sensor networks is implemented in Matlab, and the experimental results meet the expected analysis.

Abstract:In order to measure the optical rotation angle of glucose solution and sucrose solution, a rotating waveplate polarimeter is established. The polarimeter is full fiber system and uses the fiber taper to probe the optical rotation of liquid. First, through the establishment of system equations, squares optimization is used to estimate the Mueller matrix of the solution under test, and then, using the Mueller matrix decomposition to calculate the optical rotation angle of the sugar solution. Then, the optical rotation angles of glucose and sucrose solution at different concentration are measured by the experiment system. Results show that optical rotation angle linear increase with the increase of concentration of glucose and sucrose solution. Compared to the traditional measurement of optical rotation angel, the systematic polarization alignment is not necessary in our system. Consequently, the experimental operation is simple, and then the features make the system quite remote and feasible. It can satisfy the system requirements of higher precision.

Abstract:According to the principle of differential method, the main insulation structure of the capacitor voltage current transformer, the network equivalent model, through two similar operating devices are measured values, which are related to three parameters: the two phase, the same phase, the voltage measurement of the terminal screen of the same phase, the type of capacitive voltage current transformer, and the voltage measurement between the devices, and the end of the two devices, the voltage measurements, judging whether there is fault equipment, judging whether there is fault equipment, judging whether there is fault equipment, judging whether or not, judging whether there is fault equipment, judging from the two different periods, judging whether there is fault equipment, judging from the voltage measurement, and the use of differential mode, the method of measuring the capacitance type high voltage transformer equipment. Easy to use, and so on, is to carry out the operation of capacitive type substation equipment operation state detection work and a new method.

Abstract:With a large number of smart meters installation, the power utility can get a variety of information such as meter metering device via a communication network. Considering the needs of grid state estimation for metering device, we propose a general security domain model. The algorithm of calculating the network security domain by using metering device is designed in this paper. Through the security domain model and AHP in obtaining network security at the same time measuring device, given the state of metering devices affect the reliability of the key factors is estimated to improve the state estimation accuracy.

Abstract:Electric power electronic device is widely used in power system, and in the process of design of power electronic drive device, because it is not only to carry out highspeed operation, but also to carry on the fast processing of high frequency signal. Therefore, the combination of DSP and FPGA is usually used. In the design process, the communication problem of DSP and FPGA has been a focus of research. In this paper, a serial communication scheme is proposed, which is based on SPI (LVDS), FPGA (IO) and SelectIO (XC6SLX9). The DSP module is configured with SPI (TMFS28335). The scheme has the advantages of high speed of communication, strong antiinterference ability, FPGA and DSP can be separated.

Abstract:With the continuous development of research work on next generation wireless communication, millimeter wave (mmwave) and Massive MIMO technology has become the focus topics both at home and abroad. In this paper, we choose dense urban environments as our research background, according to the main lineofsight (LOS) propagation and the excellent reflection performance in millimeter wave multiuser Massive MIMO systems, we construct a simplified system model. Based on the sparsity of the beamspace channel matrix, we choose several beams that capture the channel’s main energy to approximate the original highdimensional channel, and propose a lowdimensional beamspace precoder method. The simulation results demonstrate that the reducedcomplexity precoder can also achieve considerable system sum rates. The construction of the system model and the optimization of precoder methods have strong theory value and practical significance, can provide a reference for hardware and software design and subsequent algorithm research.

Abstract:In order to increase the throughput and fully use wider bandwidth, the IEEE 802.11ax task group introduces ULMUMIMO. However, the ULMUMIMO is not specifically addressed, due to the complexity of user scheduling. Recently, heterogeneous networks have been widely discussed, and the research on CRAN provides the flexibility to the offloading between LTE and WLAN. In this paper, we propose a coscheduling model for UL MUMIMO based on the heterogeneous network scenario. Simulation results show that the proposed approach significantly improves the capacity and average throughput of the UL MUMIMO in WLAN networks.