数字图象处理技术在电厂锅炉燃烧监测中的应用研究

简要介绍了火焰辐射与温度关系的理论和图象数字处理的技术以及将它们结合用于电厂炉膛火焰动态温度分布测量的方法与实践。讨论了进一步发展的方向和实用化途径。

文献图象数字化存储系统(数字光盘)

光盘作为一种新的高密度图象、声音存储和通信载体,为信息的存储和传递开辟了广泛的途径,提供了新的媒介。光盘是一种利用激光束记录和再现信息的存贮装置。它是在七十年代迅速发展起来的。1970年 Teldoc 推出记录固定或活动图象的光盘。1978年菲利普公司展出了数字光盘。数字光盘是一种用数字扫描机,进行图象数字化处理(0和1的模数信号)记录和再现信息(包括图表、平面图等)的存贮器。

Digitalization Modeling System for Constitutive Relation of Geomaterial

A digital modeling system method is put forward for modeling constitutive relation of geomaterial including digital image subsystem for deformation measurement, numerical modeling subsystem and numerical simulation subsystem. A non-contact measurement method based on digital image processing is introduced to improve measurement of specimen deformation. Based on the method, a series of conventional tri-axial compression tests under diverse stress paths are done. Then an elasto-plastic constitutive model of soil is acquired through the numerical method of modeling constitutive law for geomaterial. Two examples of specimen deformation and ground subsidence are presented and discussed. It indicated that this method can rationally simulate the stress-strain relationship of soil, which reflects the effect of stress path on soil stress-strain relationship.

Mesomechanics coal experiment and an elastic-brittle damage model based on texture features

To accurately describe damage within coal, digital image processing technology was used to determine texture parameters and obtain quantitative information related to coal meso-cracks. The relationship between damage and mesoscopic information for coal under compression was then analysed. The shape and distribution of damage were comprehensively considered in a defined damage variable, which was based on the texture characteristic. An elastic-brittle damage model based on the mesostructure information of coal was established. As a result, the damage model can appropriately and reliably replicate the processes of initiation, expansion, cut-through and eventual destruction of microscopic damage to coal under compression. After comparison, it was proved that the predicted overall stress-strain response of the model was comparable to the experimental result.

Machine vision inspection of rice seed based on Hough transform

A machine vision system was developed to inspect the quality of rice seeds. Five varieties of Jinyou402, Shanyou10, Zhongyou207, Jiayou and IIyou were evaluated. The images of both sides of rice seed with black background and white background were acquired with the image processing system for identifying external features of rice seeds. Five image sets consisting of 600 original images each were obtained. Then a digital image processing algorithm based on Hough transform was developed to inspect the rice seeds with incompletely closed glumes. The algorithm was implemented with all image sets using a Matlab 6.5 procedure. The results showed that the algorithm achieved an average accuracy of 96% for normal seeds, 92% for seeds with fine fissure and 87% for seeds with incompletely closed glumes. The algorithm was proved to be applicable to different seed varieties and insensitive to the color of the background.

New Measurement of Swaying Quantity and Multi-barrel Parallelism for Rocket Launcher

By analyzing the deficiencies of the method, a measurement system with the technologies of photoelectricity, laser and digital image processing to synthetically measure these two parameters has been developed. A traditional method to measure the swaying quantity and multi-barrel parallelism of rocket launcher is introduced. Meanwhile, the principle, executive plan and the accuracy analysis are also presented. The photoelectric measurement system has been applied in the swaying quantity and multi-barrel parallelism measurement for Φ122 mm and Φ302 mm rocket launcher. The metrical errors are both 16^th.

Digital Autofocusing Method Based on Contourlet Transform

The autofocusing technique based on contourlet transform is discussed in this paper and an autofocusing method is proposed for images with much information in certain directions. The experimental results show that the proposed method can focus accurately and the sensitivity ratio is higher than that of the other autofocusing methods based on conventional image processing

Measuring Structural Parameters of Knitted Fabrics by Digital Image Processing Techniques

In the knitting industry the measurements of the stitch density and the stitch length are usually done manually, which may lead to lower efficiency and less definition and also bring subjective ideas into the test results. In order to improve the effect we can measure with Digital Image Processing Techniques. A piece of sample is scanned into computer and changed into a digital image, which is processed with media filtering. To acquire the power spectrum, the image in the spatial domain is converted into the frequency domain. Picking up the characteristic points describing the stitch density and the stitch length separately in the power spectra and reconstructing them, the values of the stitch density and the stitch length could be calculated. When measuring the stitch length, we should establish a geometric model of the stitch based en the digital image processing, which provides a method to transform the stitch length in the two-dimensien space into the three-dimensien space and to measure the value of the stitch length more accurately. This method also provides a new way to measure the stitch length without damaging the fabric.

Three-Dimensional Reconstruction of Live Fish through the Moire Technique

Currently, in fish farms, the controls of the physical characteristics of the fishes, for example, size and mass are made by means of the operation of fish removal, in which the tanks are emptied to capture the animals and perform the biometry. This operation demands large volumes of water and generates effluent containing high concentrations of organic matter and nutrients that can contribute to the deterioration of water quality in the recipient bodies. Therefore, the development of technologies that use digital image processing, such as the moird technique and image analysis, can be important allies for the preservation of environmental quality by avoiding the fish removal and the discharge of effluents, increasing productivity due to optimization of the time and still the saving of water. To obtain the images a 9-liter glass aquarium, a support for notebook and light projector, a digital camera brand Samsung Galaxy Camera 2 were used. The objective of this work was to obtain the three-dimensional reconstruction of live fish in aquariums. In the future, the technique can be developed to obtain the mass and the volume of the fish in fish tanks, replacing the fish removal, allowing the preservation of water resources.

Super-resolution inpainting

Image or video resources are often received in poor condition, mostly with noise or defects making the resources hard to read. We propose an effective algorithm based on digital image inpainting. The mechanism can be used in restoring images or video frames with very high noise or defect ratio (e.g., 90%). The algorithm is based on the concept of image subdivision and estimation of color variations. Noises inside blocks of different sizes are inpainted with different levels of surrounding information. The results showed that an almost unrecognizable image can be recovered with visually good result. The algorithm can be further extended for processing motion picture with high percentage of noise.

DESIGN OF MODULATION AND COMPRESSION CODING IN UNDERWATER ACOUSTIC IMAGE TRANSMISSION

This paper describes the design of modulation, compression coding and transmission control in underwater acoustic color image transmission system. This design adapts a special system of modulation and transmission control based on a DSP(Digital Signal Processing) chip, to cope with the complex underwater acoustic channel. The hardware block diagram and software flow chart are presented.

Visualization of a Turbulent Jet Using Wavelets

An application of multiresolution image analysis to turbulence was investigated in this paper, in order to visualize the coherent structure and the most essential scales governing turbulence. The digital imaging photograph of jet slice was decomposed by two-dimensional discrete wavelet transform based on Daubechies, Coifman and Baylkin bases. The best choice of orthogonal wavelet basis for analyzing the image of the turbulent structures was first discussed. It is found that these orthonormal wavelet families with index N<10 were inappropriate for multiresolution image analysis of turbulent flow. The multiresolution images of turbulent structures were very similar when using the wavelet basis with the higher index number, even though wavelet bases are different functions. From the image components in orthogonal wavelet spaces with different scales, the further evident of the multi-scale structures in jet can be observed, and the edges of the vortices at different resolutions or scales and the coherent structure can be easily extracted.

An Improved Algorithm of Harmonic Mean Filter

Rafael C. Gnzalez has mentioned an algorithm on adaptive local noise elimination filter in the book named Digital Image Processing. This paper points out the algorithm＇s deficiency and presents an improved harmonic mean filter algorithm which makes mean square error emse cutting quarter but SNR, SNPm and PSNR increasing a tenth more than original algorithm. This filter algorithm is verified to be effective by simulation experiment.