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Measurement of Optical Fiber Geometry Parameters with Bessel Function Fitting Method 被引量:1
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作者 Yiming Li Huazhong Xiang +3 位作者 Jiankun Tu Gang Zheng Minghui Chen Bin Jiang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2021年第2期74-81,共8页
Geometry parameters of optical fiber are crucial in evaluating the quality of the optical fiber.Near⁃field light distribution method is recommended in GB15972.20-2008 for the measurement of geometry parameters.To dist... Geometry parameters of optical fiber are crucial in evaluating the quality of the optical fiber.Near⁃field light distribution method is recommended in GB15972.20-2008 for the measurement of geometry parameters.To distinguish the boundary between fiber core and cladding,it is necessary to illuminate the fiber.The end face of the core is a bright spot with unclear edge,so the true edge of the core and the cladding cannot be accurately judged.A method is proposed in this paper to measure the geometry parameters of optical fiber by Bessel function fitting.Theoretically,the solution to the electromagnetic vector of mode field satisfies Bessel function,and the boundary between the core and the cladding can be precisely extracted by Bessel function fitting.Edges of the fiber were fitted by elliptical curves,and the geometry parameters of the fibers could be calculated.Results show that the maximum deviations of the diameters and the average differences of the fibers were decreased under normal and abnormal conditions respectively.The proposed method is an efficient way to obtain edge data and can improve the accuracy and stability of geometry parameters of optical fibers. 展开更多
关键词 geometry parameters of optical fiber Bessel function edge detect
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Parameterization of Longwave Optical Properties for Water Clouds 被引量:1
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作者 汪宏七 赵高祥 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2002年第1期25-34,共10页
Based on relationships between cloud microphysical and optical properties, three different parameterization schemes for narrow and broad band optical properties in longwave region for water clouds have been presented.... Based on relationships between cloud microphysical and optical properties, three different parameterization schemes for narrow and broad band optical properties in longwave region for water clouds have been presented. The effects of different parameterization schemes and different number of broad bands used on cloud radiative properties have been investigated. The effect of scattering role of cloud drops on longwave radiation fluxes and cooling rates in cloudy atmospheres has also been analyzed. 展开更多
关键词 Water cloud Long wave radiation optical property parameterIZATION Climate model
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Bio-inspired optimization algorithms for optical parameter extraction of dielectric materials: A comparative study
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作者 Md Ghulam Saber Kh Arif Shahriar +1 位作者 Ashik Ahmed Rakibul Hasan Sagor 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第10期202-208,共7页
Particle swarm optimization(PSO) and invasive weed optimization(IWO) algorithms are used for extracting the modeling parameters of materials useful for optics and photonics research community. These two bio-inspired a... Particle swarm optimization(PSO) and invasive weed optimization(IWO) algorithms are used for extracting the modeling parameters of materials useful for optics and photonics research community. These two bio-inspired algorithms are used here for the first time in this particular field to the best of our knowledge. The algorithms are used for modeling graphene oxide and the performances of the two are compared. Two objective functions are used for different boundary values. Root mean square(RMS) deviation is determined and compared. 展开更多
关键词 optical parameter extraction particle swarm optimization invasive weed optimization graphene oxide OPTIMIZATION
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Optical Dispersion Parameters with Different Orientations for SrLaAlO_4 Single Crystals
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作者 Z.El-Gohary, M.El-Nahass, H.Soliman and Y.L.El-Kady Physics Department, Faculty of Science, Menoufia University, Shebin El- Koom, Egypt Physics Department, Faculty of Education, Ain Shamd University, Cairo, Egypt 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2003年第1期77-80,共4页
The different optical dispersion parameters of SrLaAIO4 single crystals have been studied by the transmission andreflection measurements at normal incidence for the three orientations 001, 100 and 101 in the spectral ... The different optical dispersion parameters of SrLaAIO4 single crystals have been studied by the transmission andreflection measurements at normal incidence for the three orientations 001, 100 and 101 in the spectral range400 nm^2500 nm.The optical absorption data revealed the existance of allowed indirect and direct transition. Therefractive index has abnormal behaviour in the spectral region 400~900 nm, but has a normal one in the higherwavelength region. The optical dispersion parameters, the single oscillator energy Eo and the dispersion energy Edwere determined and indicated the ionic structure of the material. The high-frequency dielectric constant, the latticedielectric constant and the electronic polarizability were determined by the free carriers and the lattice vibrationmodes. The real dielectric constant (?)1, the dielectric loss tangent (tanδ), the volume (VELF) and the surface energyloss function (SELF) have also been discussed. 展开更多
关键词 optical parameters Dispersion theory Dielectric constant
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Profile Method for Measuring Apparent Optical Parameters (AOP) Ⅱin Class- Waters
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作者 李铜基 陈清莲 《Marine Science Bulletin》 CAS 2004年第1期1-8,共8页
The profile method is the principal method first to be chosen to measure the apparent optical parameters of waters. This paper first introduces the profile method briefly, then modifies Ⅱthe applied algorithm in the ... The profile method is the principal method first to be chosen to measure the apparent optical parameters of waters. This paper first introduces the profile method briefly, then modifies Ⅱthe applied algorithm in the light of the properties of the class- waters and lastly, analyses the effect of application. 展开更多
关键词 Profile method apparent optical parameters class- waters
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Optics and Spectral Investigation in Dy^(3+)-Doped Borate Glasses 被引量:2
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作者 Hou Yanyan Yang Hongxia +4 位作者 Lin Hai Ma Tiecheng Zhai Bin Wang Xiaojun Liu Xingren 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第6期661-661,共1页
Dy^3+-doped borate glasses (LBLB) with high effective visible fluorescence emission were synthesized. The absorption spectrum and fluorescence spectrum of this glass were measured and analyzed. By using J-O theory,... Dy^3+-doped borate glasses (LBLB) with high effective visible fluorescence emission were synthesized. The absorption spectrum and fluorescence spectrum of this glass were measured and analyzed. By using J-O theory, the oscillator strengths for some absorption transitions were calculated according to the absorption spectra. The intensity parameters Ω1 (t = 2, 4, 6) of Dy^3+ were determined by using a least-squares fitting approach, and the values are 4.04 × 10^-20, 1.30 × 10^-20 and 1.82 × 10^-20 cm, respectively. The root-mean-square deviation δrma was calculated. Under UV light excitation, Dy^3+-doped borate glasses (LBLB) emit intense yellowish white lights. The excitation spectrum indicates that argon laser is the effective excitation source in Dy^3+-doped LBLB glasses 展开更多
关键词 inorganic nonmetallic materials Dy^3+ ions borate glasses optical parameters luminescence spectra rare earths
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Research on optical properties of cardiovascular tissues based on OCT data 被引量:3
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作者 Na Qin Yana Liu +4 位作者 Lin Huang Yi Xin Xiao Zhang Xiaoming Hu Qin Li 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2021年第1期72-82,共11页
As a high-resolution optical imaging technology,Optical Coherence Tomography(OCT)has been widely used in the diagnosis and treatment of cardiovascular diseases.It has played an important role in the detection and iden... As a high-resolution optical imaging technology,Optical Coherence Tomography(OCT)has been widely used in the diagnosis and treatment of cardiovascular diseases.It has played an important role in the detection and identification of atherosclerotic plaques and has significant advantages.In this paper,we realized to extract the optical characteristic parameters of the target sample based on the OCT data by establishing optical transmission models conforming to the OCT principle.The optical phantoms and coronary artery of domestic pig were used as research samples to study the difference between the optical properties of the cardiovascular tissues.It can provide a basic method for further study of optical characteristic parameters of atherosclerotic plaques,and also lay a foundation for realizing the quantitative evaluation of atherosclerotic plaques with multiple optical characteristic parameters in the future. 展开更多
关键词 optical coherence tomography optical characteristic parameters theoretical model of optical transmission phantoms coronary artery
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Theoretical investigation of light generated by optical parametric down-conversion and its application in the demonstration of the EPR paradox
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作者 赵超樱 《Journal of Shanghai University(English Edition)》 CAS 2007年第2期195-196,共2页
Parametric down-conversion is a useful method to obtain non-classical state in quantum optics. (1) An analytical solution to the Fokker-Planck equation of non-degenerate optical parametric amplification (NOPA) fo... Parametric down-conversion is a useful method to obtain non-classical state in quantum optics. (1) An analytical solution to the Fokker-Planck equation of non-degenerate optical parametric amplification (NOPA) for generation of squeezed light is presented. The maximum intra-cavity compression of squeezed light derived from the analytical solution is 1/16 (vacuum fluctuations 1/4). To compare it with the previous 1/8 of degenerate optical parametric amplification (DOPA), it seems that squeezing for NOPA is superior to DOPA. 展开更多
关键词 degenerate optical parameter amplification non-degenerate optical parameter amplification quantumfluctuation EPR paradox.
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Perfect photon absorption based on the optical parametric process
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作者 Yang Zhang Yu-Bo Ma +2 位作者 Xin-Ping Li Yu Guo Chang-Shui Yu 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第6期294-299,共6页
The perfect photon absorption is studied in a cavity quantum electrodynamics(CQED) system, in which an optical parameter amplifier(OPA) is coupled to the cavity mode. This makes it possible to control the optical phas... The perfect photon absorption is studied in a cavity quantum electrodynamics(CQED) system, in which an optical parameter amplifier(OPA) is coupled to the cavity mode. This makes it possible to control the optical phase to realize the perfect photon absorption. It is found that in the presence of one and two injected fields, the perfect photon absorption is present in these two cases and can be controlled by adjusting the parametric phase. Moreover, different from the previous predictions of perfect photon absorption in atomic CQED systems, the perfect photon absorption can be changed significantly by the relative phase. Our work provides a new platform to use the parametric processes to make an available way to control the behaviors of photons and to take advantage of the optical phase to achieve the perfect photon absorption. 展开更多
关键词 photon absorption cavity quantum electrodynamics optical parameter amplifier
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Synthesis and study the influence of yttrium doping on band structure,optical,non-linear optical and dielectric results for Ca_(12)Al_(14)O_(33) (C12A7) single crystals grown using traveling-solvent floating zone (TSFZ) method
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作者 A.Abdel Moez Ahmed I.Ali A.Tayel 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期626-630,共5页
Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)single crystals were grown by using the traveling-solvent floating zone(TSFZ)method.The temperature was increased to avoid the bubbles and cracks ... Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)single crystals were grown by using the traveling-solvent floating zone(TSFZ)method.The temperature was increased to avoid the bubbles and cracks which may be formed during the preparation of the ingot material.We have started with the flux higher than the normal to avoid the bubbles and make good treatment for the solid-liquid interface.The structures of both Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)were studied by using x-ray diffraction(XRD).Optical properties for C12A7 and Y-C12A7 single crystals have been studied in order to determine the optical parameters such as optical energy gap(Eg),refractive index n,oscillating energy(Eo),dispersion energy(Ed),volume energy loss function(VELF),and surface energy loss function(SELF).Finally,a new result for these samples is that the third-order nonlinear optical susceptibility(χ(3))was determined.The results have been discussed with effect of Y-doping on the C12A7 single crystals for optical and industrial applications. 展开更多
关键词 syntheses Ca_(12)Al_(14)O_(33)(C12A7)single crystals Y-doping optical parameters dielectric results nonlinear optical susceptibility
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An investigation on the magneto-optic properties of terbium gallium garnet under high magnetic field
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作者 杨国 张国营 +3 位作者 高娇 薛刘萍 夏天 张学龙 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期631-638,共8页
This paper reports that a series of Nd3+:Er3+:yb3+ co-doped borosilicate glasses have been prepared and their absorption spectra measured. The J-O intensity parameters Ωk (k = 2, 4, 6), spontaneous radiative l... This paper reports that a series of Nd3+:Er3+:yb3+ co-doped borosilicate glasses have been prepared and their absorption spectra measured. The J-O intensity parameters Ωk (k = 2, 4, 6), spontaneous radiative lifetime Trad, spontaneous transition probability A, fluorescence branching ratio β and oscillator strength fed of the Nd3+ ions at room temperature are calculated based on Judd-Ofelt (J-O) theory. The temperature dependence of the up-conversion photoluminescence characteristics in a Nd3+:Er3+:Yb3+ co-doped sample is studied under a 978 nm semiconductor laser excitation, and the energy transfer mechanisms among Yb3+, Er3+ and Nd3+ ions are analysed. The results show that the J-O intensity parameters Ω2 increase when the Nd3+ concentration of the Nd3+:Er3+:yb3+ co-doped borosilicate glasses increases. The possibility of spontaneous transition is small and lifetimes are long at levels of 4F5/2 and 4F3/2. The intensity of Nd3+ emissions at 595, 691, 753, 813 and 887 nm axe markedly enhanced when the sample temperature exceeds 400 K. The reasons being the cooperation of the secondary sensitization from Era+ to Nd3+ and the contribution of a multi-phonon. 展开更多
关键词 Nd3+:Er3+:yb3+ co-doped borosilicate glasses optical parameters photoluminescence characteristics high temperature
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(Al_xGa_(1-x))_yIn_(1-y)P Films and Its Optical Constants on the Surface
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作者 ZHANGShu-zhi HUANGBo-biao 《Semiconductor Photonics and Technology》 CAS 1999年第2期86-91,共6页
The optical parameters for three samples of intrinsic, doped Si and doped Mg (Al x Ga 1- x ) y In 1- y P prepared by the MOCVD on GaAs substrate were measured by using ellipsometry and were calc... The optical parameters for three samples of intrinsic, doped Si and doped Mg (Al x Ga 1- x ) y In 1- y P prepared by the MOCVD on GaAs substrate were measured by using ellipsometry and were calculated by the two-layer absorption film model. The results obtained were discussed. The grown rates and thickness of oxidic layer on the intrinsic (Al x Ga 1- x ) y In 1- y P surface exposed in the atmosphere were studied. A linear dependence of oxidic layer thickness on the time was obtained. 展开更多
关键词 Ellipsometry optical parameters Oxidic Layer Two-layer Absorption Film Model CLC number:TN304.23 O472.3 Document code:A
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Hybrid optical parametrically oscillating emitter-enabled photoacoustic imaging of water:enhanced contrast,dynamic range,and multifaceted applications
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作者 Huajun Tang Yitian Tong +7 位作者 Mingsheng Li Najia Sharmin Jiawei Shi Bingfeng Li Chandra Jinata Nikki Pui-Yue Lee Kevin K.Tsia Kenneth K.Y.Wong 《Advanced Photonics Nexus》 2024年第4期136-151,共16页
Water photoacoustic microscopy(PAM)enables water absorption contrast mapping in deep biological tissue,which further allows a more detailed architecture analysis and facilitates a better understanding of metabolic and... Water photoacoustic microscopy(PAM)enables water absorption contrast mapping in deep biological tissue,which further allows a more detailed architecture analysis and facilitates a better understanding of metabolic and pathophysiological pathways.The strongest absorption peak of water in the near-infrared region occurs at 1930 nm,where the first overtone of the O-H bond lies.However,general light sources operating in this band hitherto still suffer from low optical signal-to-noise ratio and suboptimal pulse widths for photoacoustic signal generation.These lead to not only PAM contrast deterioration but also a high risk of sample photodamage.Consequently,we developed a hybrid optical parametrically-oscillating emitter(HOPE)source for an improved water PAM image contrast,leading to noninvasive and safer bioimaging applications.Our proposed source generates 1930 nm laser pulses with high spectral purity at a repetition rate of 187.5 kHz.The pulse width is flexibly tunable from 4 to 15 ns,and the maximum pulse energy is 700 nJ with a power stability of 1.79%.Leveraging these advancements,we also demonstrated high-contrast water PAM in multifaceted application scenarios,including tracking the dynamic of water distribution in a zebrafish embryo,visualizing the water content of a murine tumor xenograft,and mapping the fluid distribution in an edema mouse ear model.Finally,we showcased 1750-nm/1930-nm dual-color PAM for quantitative imaging of lipid and water distributions with reduced cross talk and imaging artifacts.Given all these results,we believe that our HOPE source can heighten water PAM’s relevance in both biological research and clinical diagnostics. 展开更多
关键词 photoacoustic microscopy WATER optical parameter near-infrared region
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Synthesis,structural study,thermal,optical properties and characterization of the new compound[C6H7N2O2]3TeCl5·2Cl
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作者 Dhaou Maraii Jordi Farjas +1 位作者 Xavier Fontrodona Mohamed Dammak 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第8期1773-1779,共7页
The new organic-inorganic compound, [C_6H_7N_2O_2]_3TeCl_5·2Cl was synthesized and its structure was determined at room temperature in the triclinic system (P^-1) with the following parameters: a = 10.5330(11... The new organic-inorganic compound, [C_6H_7N_2O_2]_3TeCl_5·2Cl was synthesized and its structure was determined at room temperature in the triclinic system (P^-1) with the following parameters: a = 10.5330(11) ?, b = 10.6663(11) ?, c = 15.9751(16)?, α = 82.090(2)°, β = 71.193(2)°, γ = 68.284(2)°and Z = 2. The final cycle of refinement led to R = 0.057 and Rw = 0.149. The crystal structure was stabilized by an extensive network of N--H···Cl and non-classical C--H···Cl hydrogen bonds between the cation and the anionic group. Several thermal analysis techniques such as thermogravimetric analysis, differential scanning calorimetric analysis and evolved gas analysis were used. We used isoconversional kinetics methods to determine the kinetics parameters. We observe that the decomposition of [C_6H_7N_2O_2]_3TeCl_5·2Cl entails the formation hydrochloric acid of nitroaniline as volatiles. The infrared spectra were recorded in the4000–400 cm^(-1)frequency region. The Raman spectra were recorded in the external region of the anionic sublattice vibration 50–1500 cm^(-1). The optical band gap was calculated from the UV-Vis absorbance spectra using classical Tauc relation which was found to be 3.12 and 3.67 eV. 展开更多
关键词 Thermal analysis Kinetics parameters Structural analysis FTIR Raman optical absorption
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Numerical Analysis of the Analytical Relationships between Angstrom Coefficients of Aerosols and Their Optical Properties for Four Types of Aerosols
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作者 Idrith Tijjani Bello Sha’aibu Uba Salman Koki Fatima 《Open Journal of Applied Sciences》 2013年第8期490-513,共24页
In this paper, the authors numerically analyzed the analytical relationships between angstrom coefficients and optical properties of aerosols to the existing data extracted from OPAC at the spectral length of 0.25 μm... In this paper, the authors numerically analyzed the analytical relationships between angstrom coefficients and optical properties of aerosols to the existing data extracted from OPAC at the spectral length of 0.25 μm to 2.5 μm at eight relative humidity for desert, urban, marine clean and continental clean aerosols. That is apart from their relationships with the wavelength that was determined, in this paper their relation with respect to aerosols’ type and RHs are determined. The properties extracted are scattering, absorption, and extinction coefficients and single scattering albedo. The results showed that the extinction and single scattering albedo are correct for all the aerosols but single scattering co-albedo is satisfied for only sahara and continental clean. 展开更多
关键词 ANGSTROM COEFFICIENTS ANALYTICAL RELATIONSHIPS parameterize Wavelength Dependence optical Properties
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Cascaded optical parameter oscillator within lithium tantalate microdisk based on two periodically poled structures
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作者 Kun Zhang Yifan Chen +7 位作者 Chongyang Xu Hongquan Yao Jian Ning Xinjie Lü Gang Zhao Peng Zhan Zhenda Xie Shining Zhu 《Chinese Optics Letters》 2025年第4期131-136,共6页
The whispering gallery resonator(WGR)represents a promising avenue for the miniaturization of optical devices,while cascaded optical parameter oscillator(OPO)processes have not been realized in the WGR,to the best of ... The whispering gallery resonator(WGR)represents a promising avenue for the miniaturization of optical devices,while cascaded optical parameter oscillator(OPO)processes have not been realized in the WGR,to the best of our knowledge.We present a microdisk with quality factors up to 3.2×10^(7),then embed two quasi-phase-matching structures inside it to demonstrate cascaded OPO.The cascaded OPO exhibits the same idler light output with the threshold of 32.7 mW at 36°C(1063.8 nm→1566.6 nm+3314.6 nm/1566.6 nm→2970.4 nm+3314.6 nm),while the operating threshold of OPO without cascade process is 4.32 mW.Moreover,diverse cascaded processes are observed,with the longest output wavelength reaching 4802.9 nm.Our results suggest the potential for a low-threshold cascade OPO based on WGR. 展开更多
关键词 whispering gallery resonator QUASI-PHASE-MATCHING cascaded optical parameter oscillator
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从全波段太阳直射辐射确定大气气溶胶光学厚度 I:理论 被引量:42
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作者 邱金桓 《大气科学》 CSCD 北大核心 1995年第4期385-394,共10页
本文提出了从全波段太阳直射辐射信息确定0.7μm波长大气柱气溶胶光学厚度的一种新方法。数值试验表明,对各类气溶胶谱分布,在水汽含量±0.2cm的误差、臭氧总量±0.1cm的误差、太阳直射辐射的±1%的观测... 本文提出了从全波段太阳直射辐射信息确定0.7μm波长大气柱气溶胶光学厚度的一种新方法。数值试验表明,对各类气溶胶谱分布,在水汽含量±0.2cm的误差、臭氧总量±0.1cm的误差、太阳直射辐射的±1%的观测误差以及太阳常数的±2%误差范围内,对小于0.1的0.7μm波长气溶胶光学厚度,它的解误差一般小于0.017,对大于0.1并小于0.6的光学厚度,它的解误差一般小10%。 展开更多
关键词 太阳直接辐射 气溶胶 光学厚度 参数化
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从宽带太阳直接辐射小时或日曝辐量反演气溶胶光学厚度研究 被引量:4
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作者 邱金桓 杨理权 《大气科学》 CSCD 北大核心 2002年第4期449-458,共10页
从宽带的太阳直接辐射1天或1小时累计量(曝辐量)气象观测资料反演气溶胶光学厚度的一个有效方法是很有用的。作者把太阳曝辐量与“等效”的瞬时太阳直接辐射关联起来,建立了一个与曝辐量“等效”的瞬时太阳直接辐射的模式;应用该模式和... 从宽带的太阳直接辐射1天或1小时累计量(曝辐量)气象观测资料反演气溶胶光学厚度的一个有效方法是很有用的。作者把太阳曝辐量与“等效”的瞬时太阳直接辐射关联起来,建立了一个与曝辐量“等效”的瞬时太阳直接辐射的模式;应用该模式和一个“等效”波长模式,发展了一个从太阳直接曝辐量反演气溶胶光学厚度的方法。作者还从试验上比较分析了由某时刻的宽带太阳直接辐射、每小时或1天的太阳直接辐射曝辐量反演得到的气溶胶光学厚度以及由太阳光度计探测的气溶胶光学厚度。试验结果表明,由日太阳直接辐射曝辐量反演得到的气溶胶光学厚度可理解为辐射加权的日平均光学厚度。 展开更多
关键词 宽带 太阳直接辐射 曝辐量 气溶胶 光学厚度
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云天地表总辐射和净辐射瞬时值的计算方法 被引量:4
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作者 孙治安 刘晶淼 +1 位作者 曾宪宁 梁宏 《气象与环境学报》 2014年第3期1-9,共9页
为减少计算机时,满足实时预报要求,全球数值预报模式中的辐射计算频率通常设定为3 h。这样处理会大大减少计算量,但同时导致较大的辐射日变化偏差,并影响模式对地面能量平衡、对流及降水的模拟。为改进这一缺陷,建立了一种辐射快速计算... 为减少计算机时,满足实时预报要求,全球数值预报模式中的辐射计算频率通常设定为3 h。这样处理会大大减少计算量,但同时导致较大的辐射日变化偏差,并影响模式对地面能量平衡、对流及降水的模拟。为改进这一缺陷,建立了一种辐射快速计算方案,可用于计算瞬时地面太阳总辐射和净辐射,使到达地面的太阳辐射计算可与模式积分同步进行,改善地面太阳辐射日变化模拟。本文介绍云天情况下的总辐射和净辐射计算方案,该方案所用的输入变量均为预报模式或卫星观测提供。结果表明:该方案既可用于数值预报模式,也可利用观测资料独立计算地面太阳辐射。通过使用美国能源部大气辐射观测资料检验,证明该方案的精度高,地面总辐射瞬时值的平均计算误差小于7%。 展开更多
关键词 太阳总辐射 大气透过率 云光学厚度 辐射参数化
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冰云短波辐射特性参数化 被引量:4
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作者 张国栋 《应用气象学报》 CSCD 北大核心 1997年第3期283-291,共9页
该文对卷云和高层云分别构造了15种冰晶尺度分布,3种云高和云厚,总共30种冰水含量、90种冰水程长模式.对尺度小于与大于30μm的冰晶粒子的单次散射特性分别用表面积等效冰球Mie理论和射线光学理论进行计算.采用del... 该文对卷云和高层云分别构造了15种冰晶尺度分布,3种云高和云厚,总共30种冰水含量、90种冰水程长模式.对尺度小于与大于30μm的冰晶粒子的单次散射特性分别用表面积等效冰球Mie理论和射线光学理论进行计算.采用delta-Eddington法计算了在4种不同地面反射率下冰云的多重散射辐射传输特性,提出了冰云辐射特性的参数化公式,指出参数化公式可以用于气候模式或大气环流模式. 展开更多
关键词 冰云 短波辐射特征 参数化
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