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	近海环境中抗生素分析样品前处理技术的研究进展期刊论文 OAI收割色谱, 2020, 卷号: 38, 期号: 1, 页码: 95-103 作者: 吕敏; 陈令新 \| 收藏 \| 浏览/下载：109/0 \| 提交时间：2020/07/08 抗生素近海前处理技术综述 antibiotics coastal pretreatment techniques review The widespread and massive usage of antibiotics for the prevention and treatment of diseases in human and animals have resulted in their continuous discharge into the environment, and finally, into the coastal environment through various pathways. Accumulation of antibiotics in aquatic organisms poses a great threat to ecological and human health, especially because it facilitates the generation and spread of bacterial resistance. Given the diverse range of antibiotics with various features, as well as their presence at low concentrations in the environment, it is imperative to develop pretreatment techniques for antibiotics in various matrices. In this paper, the pretreatment methods proposed in recent decades for antibiotics in coastal water, sediment, and biota are summarized, with emphasis on commonly used methods such as solid-phase extraction, solid-liquid extraction, matrix solid-phase dispersion, and QuEChERS. Additionally, the potential factors influencing the extraction performance and clean-up efficiency are analyzed. The advantages and disadvantages of the methods and their development are finally discussed.
	Color filtering method for CFA images based on gradient (EI CONFERENCE) 会议论文 OAI收割 International Conference on Communication Systems and Network Technologies, CSNT 2012, May 11, 2012 - May 13, 2012, Rajkot, Gujrat, India 作者: Wang Y.; Wang Y.; Wang Y.; Wang Y.; Wang Y. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 Single-sensor digital cameras capture image by covering the sensor surface with a color filter array(CFA) such that each sensor pixel only samples one of three primary color values three color is R(red) G(green) and B(blue). To render a full-color image need an interpolation process commonly referred to as CFA demosaicking is required to estimate the other two contributions for producing a full-color image. But the noise in imaging sensors not only corrupts the color filter array at the same time introduces artifacts during the color interpolation step and influence quality of images. In order to acquire high quality full-color images adopt a sort of viable and effective interpolation algorithm based on gradient at the time of removing the noise reserve image border and detail information clearly. 2012 IEEE.
	Auto-focusing evaluation functions in digital image system (EI CONFERENCE) 会议论文 OAI收割 2010 3rd International Conference on Advanced Computer Theory and Engineering, ICACTE 2010, August 20, 2010 - August 22, 2010, Chengdu, China 作者: Gao Y. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 Evaluation function is an important item to measure the quality of images in auto-focusing systems. This paper introduces four categories of evaluation functions which are respectively based on gradient correlation statistics and transform. These functions formally differ from each other and their performances are not consistent when dealing with different images. The same function also performs different when the processed images have different characteristics. Five commonly used functions from the four categories are verified and compared under different circumstances in order to validate their performances. The result provides references for variety of selections in the practical application. 2010 IEEE.
	Scene matching based on directional keylines and polar transform (EI CONFERENCE) 会议论文 OAI收割 2010 IEEE 10th International Conference on Signal Processing, ICSP2010, October 24, 2010 - October 28, 2010, Beijing, China 作者: Wang Y.; Wang Y.; Wang Y.; Wang Y.; Wang Y. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 Scene matching under complex background is a priority and difficulty in the field of computer vision it has the characteristics of rotation and scaling invariance commonly used in matching real-time collected images and photos for navigation. Scene matching techniques are faced with complex natural scenes anti-light and anti-slight-distortion the image distortion exist applicable for complex scene matching. The project has a new idea: combining the keylines with the vectors description based on polar image translation such as light and utilize the rotation-scale-invariance vectors to describe the extracted keylines change of gray levels this method includes three steps: keylines extraction perspective description and matching. Preliminary experiments show that this keylines-based scene matching algorithm is applicable for image matching under complex background. 2010 IEEE. scaling and other differences which cause matching difficult. This paper aims to find a scene matching algorithm
	An adaptive image contrast enhancement based on differential evolution (EI CONFERENCE) 会议论文 OAI收割 2010 3rd International Congress on Image and Signal Processing, CISP 2010, October 16, 2010 - October 18, 2010, Yantai, China Yang Q. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 Tubbs proposed a regularized incomplete beta function to represent some nonlinear transform functions most commonly used in image contrast enhancement. But how to define the coefficients of the beta function adaptively is still a problem. Applying the differential evolution in image contrast enhancement we utilize the global quickly search ability of the differential evolution algorithm adaptive mutation search at last searches the optimal values of beta function and gets an adaptive contrast enhanced image. To avoid trapping into local optimum a chaotic differential evolution algorithm is proposed. Experimental results show that the proposed algorithm can find the global optimal in few iterations and save largely computational time and complexity. 2010 IEEE.
	Thermal difference analysis and athermalization design of infrared optical system (EI CONFERENCE) 会议论文 OAI收割 Optical Design and Testing IV, October 18, 2010 - October 20, 2010, Beijing, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 When infrared optical system works in a large temperature range the thermal effect of optical lens and optical tube will produce image plane shift and lead to imaging quality deterioration. In order to eliminate the thermal aberration the athermalization design principles of infrared optical system were introduced and some commonly used methods of thermal difference compensation were described. Proceeding from single lens the thermal difference caused by temperature changing was analyzed and the relationship between temperature and focus shift was obtained. Considering optical tube thermal expansion a set of equations to estimate the thermal difference of lens group was given. Finally an infrared optical imaging system that can work under the temperature range of -40C to 60C was design according to athermal technique in which a new mechanical passive temperature compensation was proposed. Through simulation the athermalization design could make imaging plane shift the smallest. The simulation results coincided with the theoretical formula and the design had reference value in engineering. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Carbon content detection methods' research in the AOD furnace (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China Hui M.; Yuguo T.; Fangxiao C. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 In the process of smelting of iron alloy the carbon content has been a most important reference to the control of refining end. This article describes the commonly used off-line detection methods about carbon content of hot metal smelting furnace including chemical analysis and spectrometry and introduces the on-line measurement principle measuring devices and modeling based on the light's intensity value. 2010 IEEE.
	The analysis and design of low velocity estimation based on observer (EI CONFERENCE) 会议论文 OAI收割 2009 IEEE International Conference on Automation and Logistics, ICAL 2009, August 5, 2009 - August 7, 2009, Shenyang, China 作者: Wang D.; Zhang S. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 Low velocity servo system needs precision velocity estimation. An observer for low velocity estimation was proposed in this paper. First the source of low velocity estimation errors and the shortcomings of the single period difference were analyzed. The relationship between the estimation accuracy and estimator's frequency characteristics was concluded. Then the structure of the observer was proposed. Frequency characteristics were used to design the compensator which can stabilize the observer. The stability of the observer was also discussed. At last the observer's estimation accuracy was evaluated through a quantitative comparison. The results of simulation and experiment have shown that the quantized error in velocity estimation decreases dramatically when a velocity observer is used. Compared with some commonly-used estimators the phase lag accompanying the observer is much less. 2009 IEEE.
	Key techniques of laser direct writing patterns on spherical substrate (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Design, Manufacturing, and Testing of Micro- and Nano-Optical Devices and Systems, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Zhao J.-L.; Feng X.-G. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 Comparing with the writing method of plane pattern spherical pattern' has some remarkable different on several points. Firstly it is difficult to spin-coated a uniform photoresist film on a spherical substrate especially the ratio of spherical radius to caliber is smaller and the spin-coated way must match the ratio of spherical radius to caliber. Secondly if the sphere couldn't be regarded as a plane a so-called concentric optical scan movement way must be applied for the generation of spherical pattern because the reflex of substrate will affect the quantity of illumination. Commonly an alignment technique is indispensable with pattern generation of spherical surface by the concentric optical scan in order to ensure the orthogonal intersection of focusing laser beam and writing surface. Thirdly a uniform velocity control must be considered for the laser direct writing method on a spherical substrate. Otherwise the exposure time of photoresist will be different and the line widths of pattern will be also different at different areas. Fourthly commonly because the errors of concentric machine and substrate surface shape are bigger so focusing servo-control technique is also needful for writing a pattern on a spherical substrate. Focusing servo-control may keep the focal spot on the spherical surface by a focus detection and control system in the course of writing pattern. Using these techniques we fabricated a line width of 7m and a period of 600m isometric mesh on the concave of a spherical substrate.