Editor in chief:Prof. Sun Shenghe
Inauguration:1980
ISSN:1002-7300
CN:11-2175/TN
Domestic postal code:2-369
- Most Read
- Most Cited
- Most Downloaded
Song Jiayi , Li Bin , Chen Jie , Fan Chenyang , Huang Shaofeng
2015, 38(6):1-4.
Abstract:At present,the research of vortex shedder focused on shedder shape and size , but in the field of complex environmental conditions, the location of shedder is not fixed, there will have a certain amount of error.For a good analysis of problems about changed signal strength with spectrum brought by misalignment of the vortex shedder, the simulation model is built based on the actual physical vortex flowmeter size with the shape called triangular prism of vortex shedder by using Ansys+Workbench+FLUENT software. Then divided the simulation model into grids and get the result. After comparing the frequency of lift force with drag force, concluded that the Resistance frequency is as twice as the Lift frequency . The simulator result shows that use FLUENT to numerical simulation is feasible. Compare and analysis the signal strength with spectrum distribution at low, medium and high velocity by changing the angle between the surface of the pipe crosssection and closure. Thus we obtains the relationship between the angle of the signal strength: The effect on the signal strength is small when angle in the range of 1 degree to 7 degrees , and larger impact more than 7 degrees.
Li Shuai , Zhang Xuefan , Ren Xiufang , Meng Chunyang
2015, 38(6):5-10.
Abstract:While UHF RFID tags being attached to the surface of various materials, there will be great errors when we adopt the traditional method of cable connection test to get the tags resonance characteristics. In this paper, we formed a model of tags powerreceiving, analyzed the relationship between the energy obtained by tag chip and frequency, and then proposed a contactless method to get the resonance characteristics of UHF RFID tags. This paper detailed the principle of using the relationship between frequency and distance to test the resonance characteristics, illustrated the design concept of testing software, built and completely implemented the contactless hardware test platform. Measurement results demonstrated that the proposed method and platform can test the tags resonance characteristics effectively. In practical applications, tags for different materials can be designed according to the resonance characteristics.
Peng Zhangyou , Ren Xiufan , Meng Chunyan , Li Shuai , Chen Wentao
2015, 38(6):11-15.
Abstract:Readability of UHF RFID tags in dense environment will be influenced by mutual coupling effect between tags. The paper study mutual coupling effect from the perspective of frequency shift characteristic of antenna impedance. First, based on the structure and circuit model of inductive coupling tag antenna, the frequency characteristic of tag antenna impedance with meanderline is analyzed, in consideration of mutual coupling. Then the simulation and calculation verify the conclusion that antenna impedance shifts to lower frequencies. Combined with theory and simulation data, frequency characteristics of the mutual coupling effect is analyzed. It is put forward that the power transmission coefficient also shifts to lower frequencies, resulting in unreliable reading performance. The conclusion has guiding significance for research on the performance of the dense tags.
Tang Jiaming , Li Hui , Li Zhifang , Zhu Jinfu
2015, 38(6):16-21.
Abstract:For different effectiveness demands in wideband and smallsignal medical ultrasonic testing, three classes of ultrasonic testing conditioning circuit designs are provided, which mainly consist of discrete components type, discrete components and integrated amplifiers combination type, specific integrated circuits type variable gain amplifier respectively. Moreover, its advantages and disadvantages, applicable scope are also discussed here. An experimental circuit based on the amplifier AD8334 was finally tested, which were used to amplified ultrasound impulse and filtering to obtain a stable 80 dB amplification waveform, as well as 0.7 nV/Hz input noise density according to the signaltonoise ratio, stipulating the ultrasound receiver/ transmitter PR5800 as a standard source. The mentioned circuits can comply with the design requirements include achieving 80 dB maximum gain, 30 MHz bandwidth@80 dB, <5 nV/Hz equivalent input noise voltage well. The program may provide some useful references in the aspects of cost, flexibility, convenience concern in ultrasonic testing design.
Chen Wenhao , Zhu Liyao , Chi Hanwen , Liu Wen , Zhao Zhiyong , Deng Shijie , Huang Tongjin
2015, 38(6):22-26.
Abstract:A Giant MagnetoResistance(GMR) sensor was selected to design a magnetic encoder based on STM32 microcontroller. Dual orthogonal voltagesignals were generated by four GMR sensors which were orthogonally placed in the bottom of a columned magnet. And the two voltage signals were filtered and amplified through conditioning circuit, and converted into digital signals in STM32 chip. Rotational angle value would be accurately displayed after determined the quadrant, lookup table and performed arithmetic operation. And the output of the magnetic encoder can be flexible to choose as needed. The results showed that the magnetic encoder had a high detection accuracy and realtime.
Lu Qiupeng , Zhang Qingpeng , Qin Runjie
2015, 38(6):27-30.
Abstract:Affected by the influence of skin effect, the current density distribution on the conductor crosssection is completely different when there is high frequency current and direct current flowing through the conductor respectively. In this article, the theoretical basis of skin effect and the calculation formula of conductor resistance were introduced. With the help of Ansoft Maxwell electromagnetic field simulation software, a circular wire and a rectangular wire were modeled and simulated, and the figures of skin effect under different current frequency were given. It is also proved that with the increase of current frequency, the skin depth will be smaller and the resistance loss of the wire will be greater by comparing the current density distribution on the conductor crosssection under different frequency.
Liu Lei , Sun Xiaofei , Zhang Yu
2015, 38(6):31-33.
Abstract:Currently human hands are still not liberated when men carry things. This paper designs and implements an remote control and intelligent following car based onSTM32, ultrasonic ranging and proportional control algorithm.The car uses STM32 as its control center, and the intelligent follower mode and the infrared remote controlling mode are both available for the car. There are two ultrasonicmodulesinstalledon the front to watch thedistance between the car and the targetat each time under the following mode.SCMadopts proportional control algorithm and controls the motor speed on the left and right side according to the watcheddistance.Itcontrols the moving direction of the car according to the received infrared signal under remote controlling mode. Experimental results show the car accurately follow probability greater than 95% and response time less than 250 ms within two meters. This design accomplishes the goal that a intelligent car can automaticallyfollow the targeteven turning 360°and peoplecan control the car remotely when necessary.The system is reliable and convenient to people.
Qin Runjie , Zhang Qingpeng , Lu Qiupeng
2015, 38(6):34-36.
Abstract:With the constant improvement of the system frequency, many noise appeared, which can cause the deterioration of the system performance and make the signal integrity problems to become more and more serious. Crosstalk is a frequently encountered problem, which is caused by the capacitive coupling and the inductive coupling as the reason of edge filed generated between aggressive lines and victim lines. On the basis of the analysis of the causes of crosstalk, this paper introduced how to use a 2D field solver to solve per unit length inductance and the capacitance matrix so as to establish the SPICE circuit of transmission lines and analyze the signal integrity of multiple conductor transmission line system.
Ye Qingzhou , Ding Jinrong , Chen Jian
2015, 38(6):37-42.
Abstract:At present in the construction industry, if can be directly observed objectively underground circular tens of meters deep perfusion pile foundation for cracks and other images is very meaningful for engineering personnel. Outdoor homework this topic with related industry demand, research and development of the corresponding equipment and related software, through the deep underground waterproof camera image transferred to the pile foundation caused by the laptop display screen, on the ground can be adjusted according to different pile diameter size automatically proportional scale, at the bottom of the screen on the right side and a ruler scale, can be viewed and through the scale measure wall crack size, marked location accurate depth at the same time. When a camera when you arrive at the bottom of the pile foundation can give, and to save the resulting image and other information compression for analysis.
Yan Guangbao , Li Kaiyu , Yang Shengya
2015, 38(6):43-47.
Abstract:In order to simultaneously display information from multiple sensors, we need to fuse the image information that is acquired from infrared sensors and CCD sensor. This article make the resolution of infrared image is consistent with the resolution of the CCD image after the infrared image interpolation amplification, and get the infrared color images by using colour coding arithmetic. In order to realize the 2 pair of color image fusion, we adopt the method of color space transformation which can split color and brightness information and use different fusion strategies for each channel to fuse the image information, and realize the image fusion algorithm in FPGA.Finally,we design a set of realtime image fusion system based on FPGA.
2015, 38(6):48-53.
Abstract:This system combining the tone and stroke structures to generate nonphotorealistic image with pencil drawing effect. First , process the image with a high lift filter, which making the stroke image contained more information .Then by calculating the gradient of the gray scale, and according to the gradient do some classification. In the outline extraction stage we set two parameters, respectively, the length and depth of the pencil, by adjusting the parameters will produce different effects in the contour diagram. Texture is to build a parametric model approach to stratify the image, select the people drawn pencil texture rendering tone for each layer, but different shades weights will produce different styles of shades textures. The resulting sketch pencil drawing is convolution superimposed contour and texture, and the system can be further extended to colored pencil drawing automatically.
Yin Yanpeng , Zhou Ying , Zeng Dan , Cheng Cheng , Zhang Zhijiang
2015, 38(6):54-59.
Abstract:Face segmentation is quite challenging due to the diversity of hair styles, head poses, clothing, occlusions, and other phenomena. To improve the accuracy of face segmentation from the images with complex scenes, we present a method based on Conditional Random Fields (CRFs) in this paper. The CRFs model is defined on a graph, in which each node corresponds to a superpixel and each edge connects a pair of neighboring superpixels. The features of color and texture are used to define the node(unary) energy function, and the position distance and differences of features between adjacent superpixels are used to define the edge(binary) energy function. Segmentation is performed by inferring the CRFs model built by fusing node energy function and edge energy function. We evaluate the performance of the proposed method on two unconstrained face databases. Experimental results demonstrate that the proposed method can efficiently partition face.
Niu Min , Wu Zhanjun , Niu Yanxiong , Yang Lu , Xu Bing , Geng Tianqi
2015, 38(6):60-63.
Abstract:The median filter not only suppresses interference pulse and punctiform noise, but also keeps the image details better, therefore it plays an important role in many image processing. Moving object recognition technology needs higher and higher realtime quality in image preprocessing. In order to improve the preprocessing speed, we study the filtering algorithm and implementation scheme based on the median filter principle. And a fast image median filtering method based on the order statistics theory is proposed to realize realtime filtering. The results show that this method is the improvement of traditional median filtering sorting algorithm on hardware system, making 9 pixels of 2 dimension reduce to 5 pixels of 1 dimension to find the median in window 3×3. The comparing times, finding the median in single window, change from traditional sort of 36 times down to 16 times. Combined with the FPGA parallel processing ability and pipeline structure, filtering speed increases by almost four times, so as to satisfy the realtime image preprocessing.
2015, 38(6):64-67.
Abstract:For the purpose of image tampering localization, a fragile digital watermarking method is proposed on the basis of orthogonal fractal coding and chaos. The algorithm use the fractal coding parameters as a key to create the chaotic binary watermark to be embedded into the fractal coding field, so as to realize the image authentication. The algorithm can effectively detect whether the image is malicious tampered, and different host image will produce different chaotic binary watermark, which strengthen the confidentiality of the algorithm, especially in the face of mass image processing. The simulation results show that the proposed algorithm is efficacious and practical, and has precise tamper localization to grayscale images.
2015, 38(6):68-72.
Abstract:To solve the random gauss noise in the video, this paper proposed a spatiotemporal combination method with the combing of background extraction and foreground filtering. Video images in this paper are divided into two parts: The foreground and the background, using background difference method combined with image expanding. Then deal with the two parts using spatiotemporal combination method based on the Nonlocal means filter and direct meaning in time domain. And then the output video can be got by adding the foreground and the background which are proposed. At last, this paper give the comparison of the Nonlocal means filter and the method in this paper. Experimental results indicate that the PSNR of the tow test video after denoising reaches 33.0043、29.0365 and 35.8340、31.5261. Experiment shows that for the monitoring video with fixed background, the arithmetic in this paper effectively deal with the lowfrequency information and the highfrequency details, on the basis of reducing the complexity and improving the realtime ability of the method.
Li Guoning , Han Shuangli , Zhang Yu , Liu Yanyan , Gao Yinhan
2015, 38(6):73-79.
Abstract:With wide field of TDI CCD camera at the push of the attitude Angle of image point in the process of scanning imaging like speed difference is bigger, the row frequency matching precision is not caused by higher camera function to drop, a kind of coarse and fine adjustment precision horizontal frequency matching method was put forward. First of all, the large field of TDI CCD camera as the main characteristic of the velocity field and as the key problems of speed matching was expounded; Secondly, in the big field of TDI CCD camera Angle side swing and swing pushed sweeping imaging before and after indepth analysis of the characteristics as velocity field; Then, according to the characteristics of the velocity field choose image speed matching mode of the same speed and the different speed, analysis the functional features, the using condition of each mode; Finally, this paper proposes a support of coarse and fine adjustment precision horizontal frequency matching method, and analysis of the accuracy of the implemented row frequency matching method, ultimately meet the requirements of a given row frequency matching accuracy. The experimental results show that the integral series for level 96, coarse adjustment method can make the precision of the row frequency 0.999 425, fine adjustment method can make the precision of the row frequency 0.999 928, two methods can make the camera pass letter MTF is better than 0.998, thus realize the wide field of TDICCD camera under the condition of all kinds of big push attitude Angle scanning imaging with high quality imaging.
Zhao Yafan , Wang Kun , Yang Fan , Wang Xinghai
2015, 38(6):80-82.
Abstract:The radio controlled clock system which was using STM32 MCU as the control core and receiving Chinese code through the selfmade rod antenna displays the full time on the LCD monitor and obtains the realtime data by MCU decoding after frequency selection amplified. The system power supplied by solar energy systems with stopwatch counter timer,digital countdown timer and signal strength detection could output stability constant power. The whole system improved signaltonoise ratio adopted by AGC and displayed signal strength while reducing overall energy consumption as much as possible in order to improve power endurance. The performance of the antenna is an important influence on the performance of clock radio system, the system works excellently with clear time code signal while the field strength is 1.0mV/m and works normally while the field strength is 0.5 mV/m. The test of selecting frequency amplifier module shows that the whole system has high sensitivity while the testing data of display module shows that the system can reduce the power consumption effectively with turning off backlight by timing.
Yu Xinhua , Li Taiquan , Chen Wei , Cheng Changyan
2015, 38(6):83-86.
Abstract:With the rapid development of portable electronic products, electronic products also more and more consumers carry. In order to solve the problem of quick charge for a variety of portable electronic products, application of STM32 MCU design an intelligent multichannel Lilon battery charger .This design integrates four road charging loop, each loop control independently, without mutual influence. It is through the analog switch to respectively gating charge circuit, and use the button to select the initialization of charging parameters, using PWM wave to regulate the charging process. The experimental results show that under the premise of guarantee the charging time, this design can effectively realize multichannel charging at the same time, and through the button to choose, can choose for two kinds of the size of 3.7 V and 7.4 V lithium battery.
Li Chenyu , Cheng Zhi , Chen Feng , Du Yaohua , Bao Hongtao , Wu Taihu
2015, 38(6):87-91.
Abstract:In recent years, with great importance increasingly attached to atmospheric environmental quality, methods of quantitative analysis for the concentration of atmospheric aerosol was receiving more and more attention. The atmospheric aerosol realtime monitoring system was based on Mie scattering analytical technique, taking the advantage of LabVIEW data stream graphical programming to realize the functions of realtime process, dynamic display and historical data saved. This system analyzed the concentration of sampled various size aerosol particle by realtime getting the backscattering light intensity of every aerosol particle, which can reflect the air quality of current environment. This system had advantages of easy operation, friendly interface and abundant information, which can be widely used for atmospheric aerosol analysis area.
He Nailong , Sha Yizhuo , Xing Hongyan
2015, 38(6):92-96.
Abstract:According to resistance measuring instruments and equipment for precision resistance measurement not enough, and there is a highcost problem, This article designed a highprecision resistance measurement system based on bridge.The system uses the bridge circuit as the core of the measurement circuit, the use of STM32F103RBT6 SCM to control the core of the system, mainly to achieve acquisition and analogdigital conversion of data to measure the resistance by the reference voltage circuit and A/D module circuit, at the same time, in order to achieve highprecision measurement of the resistance, both hardware decoupling filter and software digital filtering and error compensation methods by reducing the influence of the common lead resistance , contact resistance and other types of noise. The system measures the resistance can display six significant digit by the LCD, that accuracy can reach one hundred thousandth resolution 1 mΩ;Simple operation with resistance measurement, stable data acquisition, high sensitivity and low cost characteristics, can measure all kinds of resistance, including resistance precision resistors, and apply to be applied to a variety of occasions experiments, maintenance and engineering development.
2015, 38(6):97-99.
Abstract:particularity application environment and network connectivity in wireless sensor network node, proposed the use of immune genetic algorithm to optimize the distribution of nodes covering strategy, designed to meet the network uptime in practical application, function under the conditions of implementation, make possible with a minimum number of nodes reaches the maximum coverage. Finally, the experimental analysis to verify the validity and feasibility of the algorithm.
2015, 38(6):100-103.
Abstract:In order to improve furtherly the low frequency response ability of the piezoelectric sensor and its signal conditioning circuit and extend the frequency of piezoelectric sensors, through the analysis of the frequency response of the charge amplifier circuit of the piezoelectric sensor,a method for compensation with a digital filter is proposed . Using the piezoelectric sensor calibration for input and output and matlab software,a FIR filter is designed. Through the sensor testing system with the filter in series, the original measured signal is reproduced. The simulation results show that the method makes the working bandwidth of the measurement system expand and the lowfrequency cutoff frequency of the piezoelectric measuring system is reduced furtherly,the goal to reduce the dynamic measurement error is achieved.
Li Shensong , Wen Jiaming , Liu Xuefeng
2015, 38(6):104-107.
Abstract:In order to satisfy peoples demand for realtime information, a new scheme to get sensor observation information on Android phone is proposed which combines with the current development of sensor networks and mobile devices. Based on Android platform, a mobile terminal application is designed and developed to get sensor observation information in real time by interacting with Sensor Observation Service (SOS). Through the application, sensor information and observations which users are interested in can be filtered by time, space and sensor type, and finally displayed on phone. It is proved that this scheme can get sensor information in real time by Android phone and it has feasibility and practicality.
Zhou Ying , Yin Yanpeng , Lei Rui , Zhang Zhijiang
2015, 38(6):108-112.
Abstract:Signal sparse decomposition is one of critical issues in compressed sensing. Redundant dictionary provides much more sparse decomposition than using conventional orthonormal basis function. In this paper, we propose jointly sparse model of light field based on the features of light camera arraythe images with intersignal and intrasignal correlation, and then sparse represent the signals using different linear combinations of redundant dictionary trained from original signals, and next reconstruct the sparse signals with Simultaneously stagewise Orthogonal Matching Persuit, which runs much faster than other greedy algorithms and reconstructs images simultaneously. Finally, we give several examples showing the methods are rapid and reliable in light field images.
Zuo Chaohua , Zhang Jie , Gao Hongli , Fu Pan , Chen Chunjun
2015, 38(6):113-117.
Abstract:One of the most important prerequisites for blind source separation to achieve an effective separation is to estimate the number of sources accuratly. For underdetermined problems of which the sources signal number is unkown and less than the observed signal number, this paper proposes a kind of signal source number estimation method based on Empirical Mode Decomposition(EMD), together with Singular Value Decomposition(SVD) of covariance matrix, and by means of Bayesian selection principle combining with Laplace approximation. Before procesing the observation signal with EMD, the proposed method denoised the observation signal by means of Kalman filtering algorithm in order to remove the mode mixing phenomenon of Intrinsic Mode Function(IMF). The method is validated using both simulated signals and measured signals respectively. The research on this shows that the proposed method can estimate the sources signal number exactly and provide an accurate priori information to the blind source separation.
2015, 38(6):118-121.
Abstract:The study of the valid simulation method of the echo signal of the sea surface for synthetic aperture radar is one important part of the radar simulation system. Using the characteristics of the high frequency electromagnetic scatter, one method building the radar echo signal of the sea surface in the time region by the mean of Graphic Electromagnetic Computation is established, including the construction of the sea model, the computation of the echo filed strength and the echo time signal. Based on the principle of the Stripmap SAR, the results prove this method to be valid.
Hao Xiaojun , Chen Xiang , Yan Jinghai
2015, 38(6):122-124.
Abstract:Intersystem EMC database, based on the transmitting parameters and susceptivity, is designed for improving the accuracy of EMC prediction. Structure, content and function requirement of database are described in detail, the layered EMC database design is produced according to the crossindex of all kinds of data, COM technique can guarantee the stable and extension of database in future. Based on the EMC prediction database and coupling calculation of sensitive ports, accurate Intersystem EMC prediction can be realized, which can further improve the development of EMC prediction.
Qiao Xinfeng , Mu Ping’an , Dai Shuguang , Wang Bo
2015, 38(6):125-129.
Abstract:Based on the research of corrosion resistance coupon, a new method has been proposed, which uses the lowsignal relay G6K2PY to realize the multichannel measurement of corrosion resistance coupon. A kind of corrosion resistance coupon containing 4pcs of resistance specimens, can realize the multichannel switch measurement whether the resistance specimens are exposed or inclosed. And the measurement resolution of this system can reach the level of 1μΩ.
Zhou Yaqiang , Ma Jun , Du Jun
2015, 38(6):130-134.
Abstract:In order to satisfy the requirement of greenhouse crop to be produced at high quality and high yield, the existing GSM network can be used for implementation of the system, this paper introduces a inquire and control system aims at greenhouse information through sending SMS,based on GSM communication module TC35 and STC11F32XE microcontroller . Its peripheral circuits also include five sensor modules, driver circuit module, key input module, power management module, LCD module.It aims to measure and record the temperature and humidity of the atmosphere, illuminance, carbon dioxide density and the temperature of the soil in the greenhouse.Besides that,it can be requested the information of the sensors and be controlled by SMS, this system will alarm locally and send an alarmed message to you when greenhouse environmental indicators overruns. The paper focuses on data acquisition and data transmission by GSM. We have made a prototype and a test ,through the test and operation,the system transmit data fast and accurately, important indicators of greenhouse can be adjusted fast and sensitively. It provides a method for the efficient control of greenhouse environment.
Zhang Yuqin , Wang Liang , Li Panwen
2015, 38(6):135-138.
Abstract:For the demand of monitoring and analyzing the highspeed network data and predicting the capability ,analyze the solution of the software for saving and reading the original network data. In this paper, take WinPcap as example , particularly prodict each stage of capturing network data with the inner running system, provide the detailed performance evaluation, meanwhile find out the disadvantage of capability and choke point. Then elicit the particular solution which improve the capability of each stage for improving the rate of capturing the packet obviously, saving system cost and leaving abundant resource to process and analyze the pocket. In the end,analyze and demonstrate the solution.
2015, 38(6):139-142.
Abstract:As a simple, reliable and highly standard way of communication, serial port communication is widely used in industrial automation and electrical equipment controller. The paper presents the way to implement serial port communication of a data collection system. Take Visual C++ programming as example, the key code for MSComm control is presented to implement serial port communications between computer and lower computer. It presents how to create and set up the MSComm control properties. Detailed key code design is discussed from sending perspective and receiving perspective. The communication transfer protocol is designed in details with figure illustration and code examples. The communication handshake protocol is designed in details with process presented to show how the handshake does between computer and lower compute. At the end, the running result for the system is shown. The paper also extends its strategy to long distance communications between computer and lower computer. Two designs are mentioned.
Jia Jianbo , Liu Junyan , Sun Shixian , Shang Jie
2015, 38(6):143-147.
Abstract:Rotary steerable drilling tool works in harsh environment underground. The communication system in tools need the following characteristics,such as high temperature resistance, high reliability, realtime capability and flexible expansion capability. This paper describes the design of CAN bus communication system based on HI3110 chip,introduces CAN bus communication nodes hardware structure and software work flow with HI3110 and MCU.Laboratory tests show that the communication bit error rate can reach 10-5in ambient temperature 125 ℃. The communication system meets requirements of rotary steerable tool with high temperature resistance, high reliability and realtime capability, and obtained the good effect in engineering application of rotary steerable drilling tool.
Editor in chief:Prof. Sun Shenghe
Inauguration:1980
ISSN:1002-7300
CN:11-2175/TN
Domestic postal code:2-369