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Fast Single Image Haze Removal Method for Inhomogeneous Environment Using Variable scattering coefficient

Computer Modeling in Engineering & Sciences 2020年第6期123卷 1175-1192页

作者： Rashmi Gupta Manju Khari Vipul Gupta Elena Verdú Xing Wu Enrique Herrera-Viedma Rubén González Crespo Ambedkar Institute of Advanced Communication Technologies and Research New Delhi110031India Escuela Superior de Ingeniería y Tecnología Universidad Internacional de La RiojaLogroño26006Spain School of Computer Engineering and Science Shanghai UniversityShanghai200444China Escuela Técnica Superior de Ingenierías Informática y de Telecomunicación Universidad de GranadaGranada18071Spain

The images capture in a bad environment usually loses its fidelity and contrast.As the light rays travel towards its destination they get scattered several times due to the tiny particles of fog and pollutants in the environment,therefore the energy gets lost due to multiple scattering till it arrives its destination,and this degrades the images.So the images taken in bad weather appear in bad quality.Therefore,single image haze removal is quite a bit tough task.Significant research has been done in the haze removal algorithm but in all the techniques,the coefficient of scattering is taken as a constant according to the homogeneous atmosphere but in real time this does not happen.Therefore,this paper introduces a simple and efficient method so that the scattering coefficient becomes variable according to the inhomogeneous environment.Then,this research aims to remove the haze with the help of a fast and effective algorithm i.e.,Prior Color Fading,according to the inhomogeneous environmental properties.Thereby,to filter the depth map,the authors used a weighted guided image filtering which removes the drawbacks of guided image filter.Afterwards the scattering coefficient is made variable according to the inhomogeneous atmosphere and then the Simple Color Balance Algorithm is applied so that the readability property of images can be increased.The proposed method tested on various general outdoor images and synthetic hazy images and analyzed on various parameters Mean Square Error(MSE),Root Mean Square Error(RMSE),Peak Signal to Noise Ratio(PSNR),Mean Structural Similarity(MSSIM)and the Universal Objective Quality Index(UQI).Experimental results for the proposed method show that the proposed approach provides better results as compared to the state-of-the-art haze removal algorithms.

关键词： Image dehazing scattering coefficient simple color balance inhomogeneous environment

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CHARACTERIZATION OF VITILIGO BY IN VIVO scattering coefficient OF HUMAN SKIN

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Journal of Innovative Optical Health Sciences 2011年第1期4卷 67-72页

作者： WANRONG GAO PENG LEE XIANLING ZHANG Department of Optical Engineering Nanjing University of Science and Technology 200 Xiao Ling Wei Nanjing Jiangsu 210094China

scattering coefficients of human skin in vivo with and without vitiligo were measured with optical coherence tomography(OCT).The experimental results show that there exist significant difference between the scattering coefficient of the epidermis of in vivo human skin with and without vitiligo disease.The results may be helpful for quantitatively diagnosing or evaluating the treatment of the disease.

关键词： scattering coefficient human skin vitiligo optical coherence tomography

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Study on the Repeatability of Reducing the scattering coefficient of Tissue with Hyper-osmotic Agents

Study on the Repeatability of Reducing the Scattering Coeffi...

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第三届国际仪器科学技术学术研讨会

作者： AN Yuan YAO Jian-quan College of precision instrument and Optoelectronics Engineering Tianjin University TianJin 300072 China

Using Hyper-osmotic agents to reduce the scattering coefficient of bio-tissue can enhance the detecting depth of OCT. The repeatability of this tissue-clearing effect is an important evaluating factor

关键词： Optical Coherence Tomography（OCT） scattering coefficient hyperosmotic agent repeatability refractive index surface signal ratio

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First-order approximate analytical expressions of oblique incident elastic wave at an interface of porous media saturated with a nonviscous fluid

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Petroleum Science 2022年第6期19卷 2720-2740页

作者： Dong-Yong Zhou Xing-Yao Yin Xiao-Tao Wen Xi-Lei He Zhen-Hua He State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengduSichuan610059China Key Laboratory of Earth Exploration and Information Technology of Ministry of Education Chengdu University of TechnologyChengduSichuan610059China College of Geosciences and Technology China University of Petroleum(East China)QingdaoShandong266580China

The analysis technology of Amplitude Variation with Offset(AVO)is one of the important methods for oil and gas reservoir prediction.Zoeppritz equation and its approximations are the theoretical basis of AVO analysis,which assumes that the upper and lower media of a horizontal interface are single-phase media.Limited by this assumption,AVO analysis has limited prediction and identification accuracy for complex porous reservoirs.In view of this,the first-order approximate analytical expressions of oblique elastic wave at an interface of porous media are derived.Firstly,the incident and scattering characteristics of various waves at the interface of porous media are analyzed,and the displacement vectors generated by these elastic waves are described by exponential function.Secondly,the kinematic and dynamic boundary conditions at the interface of porous media are discussed.Thirdly,by substituting the displacement vectors of incident and scattered waves into boundary conditions,the exact analytical equation is derived.Then,considering the symmetry of scattering matrix in the equation,the exact analytical expressions of each scattered wave are obtained.Furthermore,under the assumptions of small incident angle,weak elasticity at an interface of porous media,and ignoring the second-and higherorder terms,the first-order approximate analytical expressions are derived.Establishing a model of sandstone porous media with different porosity in upper and lower media,the correctness of the approximate analytical expressions is verified,and the elastic wave response characteristics of lithology and pore fluids are analyzed.

关键词： First-order approximate expressions Oblique incident wave Elastic plane wave Porous media scattering coefficient

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ASSESSMENT OF TISSUE OPTICAL CLEARING AS A FUNCTION OF GLUCOSE CONCENTRATION USING OPTICAL COHERENCE TOMOGRAPHY

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Journal of Innovative Optical Health Sciences 2010年第3期3卷 169-176页

作者： NARENDRAN SUDHEENDRAN MOHAMED MOHAMED MOHAMAD G.GHOSN VALERY V.TUCHIN KIRILL V.LARIN Department of Electrical and Computer Engineering University of Houston N308 Engineering Building 1 HoustonTX 77204USA Department of Biomedical Engineering University of Houston 2028 SERC Building HoustonTX 77204USA Department of Medicine Baylor College of Medicine HoustonTX 77030USA Institute of Optics and Biophotonics Saratov State University Saratov 410012Russia Institute of Precise Mechanics and Control of RAS Saratov 410056 Russia

One of the major challenges in imaging biological tissues using optical techniques,such as optical coherence tomography(OCT),is the lack of light penetration due to highly turbid structures within the tissue.Optical clearing techniques enable the biological samples to be more optically homogeneous,allowing for deeper penetration of light into the tissue.This study investigates the effect of optical clearing utilizing various concentrations of glucose solution(10%,30%,and 50%)on porcine skin.A gold-plated mirror was imaged beneath the tissue and percentage clearing was determined by monitoring the change in reflected light intensity from the mirror over time.The ratio of percentage clearing per tissue thickness for 10%,30% and 50% glucose was determined to be 4.7±1.6%mm^(−1)(n=6),10.6±2.0%mm^(−1)(n=7)and 21.8±2.2%mm^(−1)(n=5),respectively.It was concluded that while higher glucose concentration has the highest optical clearing effect,a suitable concentration should be chosen for the purpose of clearing,considering the osmotic stress on the tissue sample.

关键词： Glucose porcine skin percent clearing scattering coefficient optical coherence tomography

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Entropy-based multipath detection model for MIMO radar

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Journal of Systems Engineering and Electronics 2017年第1期28卷 51-57页

作者： Junpeng Shi Guoping Hu Hao Zhou Air and Missile Defense College Air Force Engineering UniversityXi’an 710051China

An optimized detection model based on weighted entropy for multiple input multiple output (MIMO) radar in multipath environment is presented. After defining the multipath distance difference (MDD), the multipath received signal model with four paths is built systematically. Both the variance and correlation coefficient of multipath scattering coefficient with MDD are analyzed, which indicates that the multipath variable can decrease the detection performance by reducing the echo power. By making use of the likelihood ratio test (LRT), a new method based on weighted entropy is introduced to use the positive multipath echo power and suppress the negative echo power, which results in better performance. Simulation results show that, compared with non-multipath environment or other recently developed methods, the proposed method can achieve detection performance improvement with the increase of sensors.

关键词： multiple input multiple output (MIMO) radar weighted entropy multipath distance difference (MDD) scattering coefficient likelihood ratio test (LRT)

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Biomimetic Material Simulating Solar Spectrum Reflection Characteristics of Yellow Leaf

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Journal of Bionic Engineering 2018年第4期15卷 741-750页

作者： Kai Xu Yang Lin Xuezhong Wei Hong Ye Department of Thermal Science and Energy Engineering University of Science and Technology of China Hefei 230027 China Beijing Institute of Space Launch Technology Beijing 100076 China

To counter the threat of hyperspectral detection, it is necessary to develop biomimetic materials to simulate the solar spectral re- flection characteristics of plant leaf accurately. Two kinds ofmembranaceous yellow biomimetic materials were prepared by dispersing the particles of chrome titanium yellow and iron oxide yellow as fillers in polyvinyl alcohol films respectively. Reflectance and transmittance of the biomimetic materials were measured, and absorption and scattering coefficients of the biomimetic materials were inverted with a four-flux model. Results indicate that the biomimetic material adopting chrome titanium yellow particles can simulate the solar spectrum reflection characteristics of yellow leaf because of the similar absorption and scattering characteristics. The biomimetic material adopting iron oxide yellow particles cannot simulate the spectrum reflection characteristics of yellow leaf near the wavelength of 900 nm due to the characteristic absorption of the iron oxide. When the volume fraction of the chrome titanium yellow particles is lower than 2.12%, the absorption and scattering coefficients both increase approximately linearly with the volume fraction, indicating that the particles can scatter radiation independently. Therefore, the reflectance of the biomimetic material can be regulated through linearly changing of the volume fraction of the chrome titanium yellow particles.

关键词： biomimetic material yellow leaf solar spectrum reflection four-flux model absorption coefficient scattering coefficient

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OPTICAL PROPERTIES OF SKIN,SUBCUTANEOUS,AND MUSCLE TISSUES:A REVIEW

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Journal of Innovative Optical Health Sciences 2011年第1期4卷 9-38页

作者： ALEXEY N.BASHKATOV ELINA A.GENINA VALERY V.TUCHIN Institute of Optics and Biophotonics Saratov State University Saratov 410012Russia Institute of Precise Mechanics and Control of RAS Saratov 410028Russia

The development of optical methods in modern medicine in the areas of diagnostics,therapy,and surgery has stimulated the investigation of optical properties of various biological tissues,since the efficacy of laser treatment depends on the photon propagation and fluence rate distribution within irradiated tissues.In this work,an overview of published absorption and scattering properties of skin and subcutaneous tissues measured in wide wavelength range is presented.Basic principles of measurements of the tissue optical properties and techniques used for processing of the measured data are outlined.

关键词： Absorption coefficient scattering coefficient anisotropy factor reduced scattering coefficient refractive index

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Mode error analysis of impedance measurement using twin wires

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Chinese Physics C 2015年第3期39卷 66-70页

作者：黄良生入江吉郎刘瑜冬王生 Dongguan CampusInstitute of High Energy PhysicsChinese Academy of Sciences Dongguan Institute of Neutron Sciences High Energy Accelerator Research Organization

Both longitudinal and transverse coupling impedance for some critical components need to be measured for accelerator design. The twin wires method is widely used to measure longitudinal and transverse impedance on the bench. A mode error is induced when the twin wires method is used with a two-port network analyzer. Here, the mode error is analyzed theoretically and an example analysis is given. Moreover, the mode error in the measurement is a few percent when a hybrid with no less than 25 dB isolation and a splitter with no less than 20 dB magnitude error are used.

关键词： coupling ilnpedance accelerator twin wires mode error scattering coefficient

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Characterization of Blue-Green Light Non-Line-of-Sight Transmission in Seawater

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Optics and Photonics Journal 2022年第11期12卷 234-252页

作者： Xizheng Ke Gang Li Faculty of Automation and Information Engineering Xi’an University of Technology Xi’an China Shaanxi Civil-Military Integration Key Laboratory of Intelligence Collaborative Networks Xi’an China College of Physics and Electronics Shaanxi University of Technology Hanzhong China

The blue-green light in the 450 nm to 550 nm band is usually used in underwater wireless optical communication (UWOC). The blue-green light transmission in seawater is scattered by the seawater effect and can achieve communication in non-line-of-sight (NLOS) transmission mode. Compared to line-of-sight (LOS) transmission, NLOS transmission does not require alignment and can be adapted to various underwater environments. The scattering coefficients of seawater at different depths are different, which makes the scattering of light in different depths of seawater different. In this paper, the received optical power and bit error rate (BER) of the photodetector (PD) were calculated when the scattering coefficients of blue-green light in seawater vary from large to small with increasing depth for NLOS transmission. The results show that blue-green light in different depths of seawater in the same way NLOS communication at the same distance, the received optical power and BER at the receiver are different, and the received optical power of green light is greater than that of blue light. Increasing the forward scattering coverage of the laser will suppress the received optical power of the PD, so when performing NLOS communication, appropriate trade-offs should be made between the forward scattering coverage of the laser and the received optical power.

关键词： Underwater Wireless Optical Communication Non-Line-of-Sight Transmission scattering coefficient Received Optical Power Bit Error Rate

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