Xuyan Zhou

The Hydrological Sediment Detection System Based on Image Process

We propose the hydrological sediment detection system based on image process. It consists of image collection subsystem, network transmission subsystem andARM-based processing subsystem based on PXA270 processor. The systems configuration and structure is described. The system gets the image of mountain rivers flow section by using on-line technique and then proceed to hydrological analysis of sediment by the appropriate image algorithm. The characteristic ofsystem is image segmentation algorithm based on a wavelet level Markov model and the multi-direction one-dimensional wavelet transformation microscopic image denoising algorithm. The experiment show that hydrological sediment detection system could get the sediment concentration of mountain rivers flow on-line.

A Study of Image-Based Algorithms of River Sediment Measurement

Letting an underwater camera sunk into a pre-set vertical location by using the existing hydrology cableway in river, When the computer in the bank workstation issued camera control commands, the underwater camera begins taking photo to water samples, and the image transmitted to the image acquisition card, and transmitted the image data which be collected by ARM to the bank workstations. Various pieces of image be denoising, segmentation, calculation and processing by riparian workstation computer, and thus arrive at the river sediment content. This proposed method image-based content of river sediment detection techniques applied to the lower sediment concentration (30kg/m3) of river sediment measurements and used in hydrological stations of Wujiang City, Ji’an practical, the application results show that the method than the traditional drying method in time, a decrease of 96% accuracy compared with the drying method error of 1% -5%, in line with norms of hydrologic and sediment measurements. Although the method for the large sediment (100kg/m3) river sediment concentration measurement still falls short of expectations, but it can still test method used for the design and optimization to provide a frame of reference.

On the Way to Design an Optical Camera Lens for River Sediment in Underwater Imaging

In order to real-time gathering the images of underwater sediment, an optical imaging system should be designed for the optical imaging of the sediment. As water and air has a different refractive index, so when light from the aqueous medium aiming at the phenomenon of refraction of air will occur, the objective lens’s angle of vision will become smaller (focal length), magnification decreases, aberrations have also changed, in which color deviation and distortion significantly increased, so that deterioration of image quality, image distortion and resolution reduction. In order to solve the above problems, the underwater sediment illumination imaging system designed in this paper using active illumination imaging systems, and analyzed imaging focal length, imaging distance, Light source and camera angle etc. in the imaging system. Because of the Water absorption of light, scattering, and changing refractive index, this optical imaging system designed for specific using environmental of river sediment camera dedicated optical imaging system to ensure the systems image quality.

Method for monitoring river sediment on-line using image slice based on five-point

To analyze the River Sediment water sample collection process based on five-point, a video camera on the water samples collected in the process of continuous chip camera is proposed. The images obtained for each slice were sent to the bank after the workstation de-noising, segmentation and binarization processing, and then according to the volume of sediment particle equivalent spherical degrees and the average density to calculate the overall content of river sediment method. Various pieces of image be denoising, segmentation, calculation and processing by riparian workstation computer, and thus arrive at the river sediment content. This proposed method applied to the lower sediment concentration of river sediment measurements and the application results show that the method than the traditional drying method in time, a decrease of 96%, accuracy compared with the drying method error of 1%–5%, in line with norms of hydrologic and sediment measurements.

Transformation of hydrology cableway observation system based on EKL-3

In order to enhance the reliability of EKL-3 hydrology cableway observation system and the sampling accuracy, we transformed the inlet valve of this system, river bottom weightlessness and the data communication module, then revised the way of measuring according to the hydrology code requirement. To avoid the remaining silt to catch the valve in the sampling process we used the double barrel bistability valves; Installed a normally closed “weightlessness” switch on the winch lifting cable to solve the tray type river bottom weightlessness which is unable worked when it falls into sludge;we have solved the wireless signal weaken quick in the water by the double audio communication method. The test result in XIAJIANG station, WUJIANG station, the BAISHA station indicated that the reliability of the system is enhancement, the sampling precision to be able to sharpen, the transmission signal antijamming ability as well as anti-weaken ability can strengthen, and this system maintenance is convenient, especially qualify in small rivers hydrology data gathering and survey.