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According to the actual demand of the system, the paper proposed scheme and implement for the stored-grain grossness remote monitoring system based on GPRS and Zigbee. The test result is shown that the max error is ∼0.02mA between inversion value of the server-side data and the measure value. The design should be served as the useful reference to the study of acquisition technology in similar system.

The paper proposed scheme and implement for the grossness inspection system of grain depot based on the actual demand of the system and the electrical confine analysis on the application environment. The test results is shown that, on the communication condition of 1Km distance and 5Kbps rate, the mistake code didn’t appeared and the measure error is less than 2.4% in the relative MSD, which can meet with the precision demand of the inspection system. The design should be served as the useful reference to the study of acquisition technology in similar system.

To need the requirement of measuring the grain quantity in the barn, the pressure sensors are mounted on the ground and the wall of the barn, and the grain quantity can be calculated by using these measurement values. To realize the data transmitting reliability and real time, the design proposal of the measurement node of the CAN-bus by using the chips of AT89C51 and the SJA1000 is put forward, and the design of software and the hardware of the node is given. To verify the effectivity and the reliability of the measurement node, some experiments are done, the results shown that, the measurement error is no more than 3% under the conspicuous level is equal to 0.05, the grain quantity can be measure by this system completely.

Based on the properties of transient feeble optical signal, which is the wide dynamic range and the feeble lower limit signal, it is presented a novel detecting scheme compressing signal real-time in logarithmic domain in this paper. After the principle analysis of the scheme, it has been implemented to choose appreciate parts, design the circuitry and test. The results indicated that the approach can make transient optical signal ranged 120dB compress in the range of 0~5V. And together with the circuitry design simplified and the dissipation decreased, the troubles at the back data acquisition module can be lessened greatly. It may be a novel clue for research on the tech of detecting the transient light and provide certain reference values to similar system design.

In order to analyze the influence of the satellite jitter on the image quality of the remote sensing camera, the image motion introduced by the low frequency sine jitter was given. The influence of the image motion along the roll, pitch and yaw direction on the image quality was studied chiefly. Finally, the degradation of the image quality caused by the jitter was computed concretely according to the datum come from two kinds of the emulation on the satellite kinetic jitter. The results showed that, with the increase of TDICCD integration number, the requirement of remote sensing camera for jitter amplitude is more stringent, and must be limited.

In this study, we present an integration scheme of preprocessing circuit for detecting optical pulse based FPGA-tech. Using the photoelectric detection technique, the scheme includes a the photodiode detector (PDD), which can convert an optical pulse to a small current signal; and a FPGA produces code to control MUXes for different channel, which changes circuit parameters to adapt different detection situation. Design issues are addressed. Testing circuits are implemented. Simulation wave displayed on the oscillograph and the data of the system acquiring are presented. And the feasibility of the scheme is confirmed by the data analyse. Presently, the scheme has been used in a lightning detection system.

Extracting the clear fundus images information is a prerequisite for diagnosing the patients’ conditions exactly in clinic. This paper adopts respectively de-noising algorithm based on multi-scale and that based on median filter to process real fundus images. It gives the LMLSD algorithm based on Gaussian wave extraction, which is used to estimate SNR (Signal-to-Noise) of the processed images and give an objective quantitative evaluation to treatment effect of the above two de-noising algorithms. The results show that the image processed by multi-scale algorithm is much clearer, and SNR increases significantly. The results of objective quantitative evaluation are in accordance with subjective visual feeling, so the selecting of evaluation algorithm is appropriate.

—A method for threshold selection to detect edge width of objects in the image was presented. Three order spline wavelet was choosed to complete multiscale wavelet edge detection and wavelet edge module values were obtained. After properties of these data was analyzed, a method for threshold selection was proposed using half of maximum of wavelet edge module values. Edge width of objects in the image was given a definition and can be calculated by area and girth of the transition edge using the threshold selected by the method proposed. Experiment results show that the algorithm is effective and performs better.