This paper is based on the digital waveform synthesis techniques,designed and implemented a new digital phase standard *** amplitude,frequency and phase of the phase-source system can be adjusted,the output sine wave ...
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This paper is based on the digital waveform synthesis techniques,designed and implemented a new digital phase standard *** amplitude,frequency and phase of the phase-source system can be adjusted,the output sine wave frequency ranges of 10Hz-100kHz and the phase adjustable ranges of-180°-180°.By extending the voltage amplifier and transconductance amplifier,the voltage output can up to 600V,the current can up to 100A,the resolution can up to 0.0017°and the phase accuracy can up to 0.005°.This circuit design is simple,reliable,and can be controlled by programs *** it can be applied for highly accurate calibration and test as standard sine wave signal source and phase source.
It is necessary to accomplish running a single instance for test software that need to own a software resource or hardware resource *** are three common methods to accomplish running a single instance including "...
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It is necessary to accomplish running a single instance for test software that need to own a software resource or hardware resource *** are three common methods to accomplish running a single instance including "Looking up the caption of the main window of the application", "Using thread mutex" and "Using Windows global atom".These methods have the imperfections of *** imperfections may result in serious aftereffect for the high reliability system.A new method for such problems is puts forward,that is accomplish running a single instance of the application through cooperation of main window handle and thread *** the method can not only solve the imperfections of reliability completely but also reduce the complexity of program and improve efficiency of program.
In the paper,the noise feature of X-ray image intensifier visual system is analyzed by using 3-dimesion model based on time domain,the different kinds of noise factors are defined,the spatial and temporal noises in th...
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In the paper,the noise feature of X-ray image intensifier visual system is analyzed by using 3-dimesion model based on time domain,the different kinds of noise factors are defined,the spatial and temporal noises in the view of the system is tested and analyzed,and the 3-dimesion noise of the X-ray image intensifier visual system with different incidence parameters is measured and *** result has showed that it match the practical capability of X-ray image intensifier.
Coordinate positioning of turbulence tracing particle based on cross correlation matching and image projection transformation is *** the basis of extracting wavelet high-frequency components of turbulence conjugate se...
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Coordinate positioning of turbulence tracing particle based on cross correlation matching and image projection transformation is *** the basis of extracting wavelet high-frequency components of turbulence conjugate sequential images in continuous time-points,cross correlation matching is applied to definite tracing particle's relative location in the projected images,and then relationship of three-dimensional projection transformation is established to calculate particle's absolute space *** analysis and data comparison indicate that accurate coordinate positioning result of tracing particle can be obtained by this method,turbulence feature and its motion discipline can be displayed finely.
In video stream,a method was mentioned that combining gray level projection and human iris saturation information based on HIS color space with template matching and Kalman filter in order to improve the robustness of...
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In video stream,a method was mentioned that combining gray level projection and human iris saturation information based on HIS color space with template matching and Kalman filter in order to improve the robustness of human eye positioning and tracking,accuracy and detection speed,and improve the applicability of the ***,the gray level projection method to locate eyebrow regions was adopted,then human iris saturation information was used to locate the eyes ***,according to the characteristics of Kalman filter,the location of the human eye to appear in the next frame would be estimated,and template matching would run in limit range in order to determine the exact location of the *** experimental results show that the right accuracy of eye positioning is 85%,positioning time is 0.0726s,the rate of eye tracking could reach 17 f/s,the accuracy of eye tracking is 87.5%.
This paper designs the electromagnetic flowmeter in partially filled pipes(EMF-PF),which sensor sets four *** pair of the electrodes is set on the pipe bottom as the signal injection electrodes that inject the AC puls...
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This paper designs the electromagnetic flowmeter in partially filled pipes(EMF-PF),which sensor sets four *** pair of the electrodes is set on the pipe bottom as the signal injection electrodes that inject the AC pulses used to determine liquid fill *** pair of long-arc electrodes is set on the pipe wall as the measurement *** measurement electrodes alternate duties,sensing both the flow and fill height *** the flow and fill height raw signals are disposed in different time period by the same signal processing *** result shows that the designed EMF-PF can achieve the flow measurement in partially filled pipes,and the measurement accuracy of this EMF-PF meets the actual requirements.
Astronomical Positioning and Orientation plays an indispensable role in missile launch,inertial platform calibration,aerospace and so *** this paper,an astronomical surveying scheme based on modern motor-driving elect...
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Astronomical Positioning and Orientation plays an indispensable role in missile launch,inertial platform calibration,aerospace and so *** this paper,an astronomical surveying scheme based on modern motor-driving electronic theodolite /total station is *** addition,the research on automatic star finding method is undertaken by use of the electronic theodolite driven by the Leica-TPS1000 motor. Finally,comparison is made between results from actual measured data and data from the method mentioned above,and corresponding conclusions are made.
An embedded mine ventilator's condition monitoring and fault prediction system is described in this paper,in which the mine ventilator's voltage,electric current, power,rotational speed,torque,hotbox,wind pres...
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An embedded mine ventilator's condition monitoring and fault prediction system is described in this paper,in which the mine ventilator's voltage,electric current, power,rotational speed,torque,hotbox,wind pressure, vibration intensity and other operating parameters are monitored by wireless ZigBee and GPRS *** addition, the data are submitted to the fault diagnosis and prediction servers via the wireless network for realizing the remote on-line monitoring,diagnosis and prediction of the mine ventilator's.
In this paper,a novel velocity measurement method based on laser feedback effect of Zeeman-birefringence dual-frequency laser has been *** experimental setup based on an optical feedback dual-frequency laser is develo...
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In this paper,a novel velocity measurement method based on laser feedback effect of Zeeman-birefringence dual-frequency laser has been *** experimental setup based on an optical feedback dual-frequency laser is developed to realize velocity value and direction discrimination utilizing phase delay between the optical feedback fringes of the two orthogonally polarized *** the external cavity stretches,the optical feedback curve of the parallel light exceeds that of the vertical lightπ/2 in *** the contrary, the optical feedback curve of the parallel light lags that of the vertical lightπ/2 in *** properties can be used to achieve the velocity value and the direction discrimination of the displacement and ***,it can meet some demands of non-contact and high-precision velocity measurements.
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