Journal of Quantitative Spectroscopy & Radiative Transfer最新文献_第7页

Learning to precondition: Reinforcement learning enhanced three-level circulant preconditioning for the Discrete Dipole Approximation 学习到先决条件：离散偶极子近似的强化学习增强三层循环先决条件

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2025-11-12 DOI: 10.1016/j.jqsrt.2025.109741

Steven Lanier

Simulating light interaction with complex arbitrary geometry is crucial across the sciences. The Discrete Dipole Approximation (DDA) offers versatility for such problems but faces significant computational challenges, particularly for optically large or high-index systems, limiting its practical scope. Prior circulant preconditioning work, building on frameworks by Chan and Olkin and applied to DDA by Groth et al., demonstrated speedups primarily for quasi-2D geometries while attempts to create stable three-level preconditioners for general 3D structures were unsuccessful. Here we present an efficient and robust DDA implementation featuring a successful three-level circulant preconditioner stabilized through several key enhancements: optimized complex diagonal elements, controlled dimensional expansion and folding of the preconditioner structure, and automated parameter tuning via reinforcement learning. This preconditioning strategy is integrated with a custom GPU iterative solver incorporating stability improvements. Our approach effectively handles arbitrary 3D geometries, including non-homogeneous objects with varying refractive indices and multi-object scenarios with differing material values. The implementation yields substantial computational gains, often exceeding an order of magnitude reduction in iteration count or solution time, enabling convergence for more traditionally difficult problems and reducing demanding simulations from hours to minutes or even seconds on standard hardware. This work significantly extends the range of complex systems amenable to DDA modeling, facilitating advanced electromagnetic simulations relevant to nanophotonics, materials characterization, and atmospheric/biological optics.

模拟光与复杂任意几何的相互作用在各个科学领域都是至关重要的。离散偶极近似（DDA）为此类问题提供了多功能性，但面临重大的计算挑战，特别是对于光学大或高折射率系统，限制了其实用范围。先前的循环预处理工作，建立在Chan和Olkin的框架之上，并由growth等人应用于DDA，证明了主要针对准二维几何图形的加速，而试图为一般3D结构创建稳定的三层预处理则失败了。在这里，我们提出了一个高效和鲁棒的DDA实现，其成功的三级循环预调节器通过几个关键的增强来稳定：优化复杂对角元素，控制预调节器结构的维度扩展和折叠，以及通过强化学习的自动参数调谐。这种预处理策略集成了一个定制的GPU迭代求解器，其中包含稳定性改进。我们的方法有效地处理任意三维几何，包括具有不同折射率的非均匀物体和具有不同材料值的多物体场景。该实现产生了大量的计算收益，通常超过了迭代计数或解决时间的数量级减少，使传统上更困难的问题能够收敛，并将标准硬件上的苛刻模拟从几小时减少到几分钟甚至几秒钟。这项工作极大地扩展了适用于DDA建模的复杂系统的范围，促进了与纳米光子学、材料表征和大气/生物光学相关的先进电磁模拟。

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引用次数: 0

Reciprocal and nonreciprocal near-field radiative heat transfer between bio-inspired spiny particles under a magnetic field 磁场下仿生刺状粒子间的互反和非互反近场辐射传热

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2025-11-12 DOI: 10.1016/j.jqsrt.2025.109738

Zhiguo Xu, Fuquan Zhang

Inspired by the spiny structure in the nature, this study applies the anti-reflection properties of cicada wing structures to near-field radiative heat transfer. The surface microstructure of different cicada wings is observed by SEM, their reflectivity is measured and a model for spiny particles is simplified and established. Thermal discrete dipole approximations method and magneto-optical materials InSb under a magnetic field is used to investigate spiny particles. The nonreciprocal near-field radiative heat transfer between four spiny particles is considered. Effects of spine radius, magnetic field and spine gap are studied. The interaction between scattering of different peaks in spiny particles leads to the valleys and peaks in relative conductance. As the magnetic field increases, the redshift and blueshift of the split peaks reduce the surface polaritons scattering interaction between the resonance main peak and the split peaks. The net clockwise conductance and overall persistent heat transfer ratio increases when the spine radius increases. The overall persistent heat transfer ratio of particles decreases when the gap increases.

本研究受自然界棘状结构的启发，将蝉翅结构的抗反射特性应用于近场辐射传热。利用扫描电子显微镜观察了不同蝉翅的表面微观结构，测量了蝉翅的反射率，简化并建立了蝉翅的棘粒模型。利用热离散偶极近似法和磁光材料InSb在磁场下研究了棘粒子。研究了四棘粒子间的非互易近场辐射传热问题。研究了脊柱半径、磁场和脊柱间隙的影响。不同波峰散射之间的相互作用导致了相对电导的波谷和波峰。随着磁场的增大，分裂峰的红移和蓝移降低了共振主峰与分裂峰之间的表面极化子散射相互作用。当脊柱半径增大时，净顺时针电导和总持续传热比增大。随着间隙的增大，颗粒的总持续换热比减小。

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引用次数: 0

Semiclassical dynamics of the lemniscate ordered emitters enhanced by plasmon-polaritons in nanorings 纳米粒子中等离子体极化增强的微星有序发射体的半经典动力学

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2025-11-11 DOI: 10.1016/j.jqsrt.2025.109740

Gennadiy Burlak , Gustavo Medina-Ángel

The semiclassical dynamics of optical nanoemitters (NEs) arranged in the shape of a Bernoulli lemniscate (LB), enhanced by plasmon–polaritons (PPs) in a lattice of conducting nanorings (NRs), are investigated. The coupling of PP and NE is mediated by a common optical field and NE with a finite lifetime of pumping are considered. Using the FDTD approach, it is found that the field structure and the NE dynamics significantly depend on the plasma frequency of the NR. If the intersection point of the LB branches (the region of high NE density) is located inside the NR gaps, a significant increase in the laser field strength and quantum cross-correlations in the NE subsystem occurs. This effect may be exploited to create new types of emitting devices using dispersed nano-objects in modern nanoelectronics.

研究了导电纳米晶格中等离子体极化子（PPs）增强的伯努利透镜状光学纳米发射体（NEs）的半经典动力学。PP和NE的耦合是由一个共同光场介导的，并考虑了具有有限抽运寿命的NE。利用时域有限差分方法，发现场结构和NE动力学显著依赖于NR的等离子体频率。如果LB分支的交点（高NE密度区域）位于NR间隙内，则NE子系统中的激光场强和量子互相关会显著增加。在现代纳米电子学中，利用这种效应可以利用分散的纳米物体来制造新型的发射器件。

引用次数: 0

Standing photonic jets for stable nanoparticle trapping in cut-cylinder microfluidic channels 静止光子射流在切割圆柱微流体通道中捕获稳定纳米颗粒

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2025-11-11 DOI: 10.1016/j.jqsrt.2025.109739

Renxian Li , Yuexiao Jiao , Li Xiao , Huan Tang , Bing Wei , Shuhong Gong , Denis Novitsky , Igor V. Minin , Oleg V. Minin

Optical forces proved to be extremely useful for manipulating and trapping nano- and microparticles. Such applications are especially needed for microfluidic systems to reliably control streams of nanoparticles. In this paper, we propose to optically trap nanoparticles using an inclined photonic jet modulated by a standing wave and generated with a cut cylinder partially blocked from the incident plane waves by a variable metal screen. Our theoretical analysis is based on the Finite Difference Frequency Domain (FDFD) method for the electric field and the optical energy flux calculations and on the Rayleigh model for the optical force calculation. The effects of the cut-cylinder central angle and shape of the metal screen on the standing wave formation and the optical force distribution are numerically demonstrated. We show that the quality of the optical trap can be increased by adjusting the parameters of the model cut-cylinder central angle and estimating the stability of the resulting trap. The cut cylinder can be used as an ingenious microfluidic channel that has potential applications for the optical trapping of nanoparticles and the development of optical tweezers.

事实证明，光力在操纵和捕获纳米和微粒方面非常有用。这种应用特别需要微流体系统来可靠地控制纳米颗粒流。在本文中，我们提出了利用由驻波调制的倾斜光子射流来光学捕获纳米粒子，并通过可变金属屏部分阻挡入射平面波产生切割圆柱体。我们的理论分析是基于有限频域差分法（FDFD）计算电场和光能通量和光力计算的瑞利模型。数值模拟了金属屏的截圆柱圆心角和形状对驻波形成和光力分布的影响。我们表明，通过调整模型切割-圆柱圆心角的参数和估计所产生的阱的稳定性，可以提高光阱的质量。切割后的圆柱体可以作为一种巧妙的微流体通道，在纳米粒子的光学捕获和光镊的开发方面具有潜在的应用前景。

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引用次数: 0

The HITRAN2024 methane update HITRAN2024甲烷更新

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2025-11-07 DOI: 10.1016/j.jqsrt.2025.109736

T. Bertin , I.E. Gordon , R.J. Hargreaves , J. Tennyson , S.N. Yurchenko , K. Kefala , V. Boudon , C. Richard , A.V. Nikitin , V.G. Tyuterev , M. Rey , M. Birk , G. Wagner , K. Sung , B.P. Coy , W. Broussard , G.C. Toon , A.A. Rodina , E. Starikova , A. Campargue , G.B. Rieker

Spectroscopic parameters of methane from many different studies were gathered to improve the HITRAN database towards its 2024 version. After a validation process using high-resolution FTS and CRDS spectra, about 80,000 lines of the four most abundant isotopologues were replaced from the dyad to the triacontad regions. These changes amount to 51,000 transition wavenumbers, 18,000 line intensities, 33,000 pressure-broadening half-widths, and 3300 assignments. 44,000 new lines were added with 16,000 old lines removed, extending the database from 12,000 cm⁻¹ up to 14,000 cm⁻¹, and covering some gaps. A greater focus was brought on the pentad, octad, and tetradecad regions, targeted by several remote sensing instruments. In these regions, comparisons of spectral fits from multiple line lists were performed, taking only the parameters that provide best fit for each line. In the

ν_{3}

band, in addition to replacing the previous values, speed-independent pressure broadening parameters of ¹²CH₄ were gathered and used to fit Padé-approximant functions. These functions then replaced any outdated experimental data in

ν_{3}

, missing data in the new lines, as well as the values that were determined to be outside their physical boundaries. The CH₃D broadening parameters were replaced in the same manner, for missing and low or high values, using a semi-empirical formula instead.

从许多不同的研究中收集了甲烷的光谱参数，以改进HITRAN数据库，使其达到2024年的版本。在使用高分辨率FTS和CRDS光谱进行验证后，将四种最丰富的同位素的约80,000行从二元区替换为三重区。这些变化总共有51,000个过渡波数，18,000个线强度，33,000个压力加宽半宽度和3300个分配。增加了44,000条新线，删除了16,000条旧线，将数据库从12,000 cm−1扩展到14,000 cm−1，并覆盖了一些空白。更加注重几项遥感仪器所针对的五进制、八进制和十进制区域。在这些地区，对来自多个谱线列表的光谱拟合进行比较，只采用最适合每条谱线的参数。在ν3波段，除了替换之前的值外，还收集了与速度无关的12CH4的压力展宽参数，并用于拟合pad近似函数。然后，这些函数替换了ν3中任何过时的实验数据，新行中缺失的数据，以及确定超出其物理边界的值。CH3D展宽参数以相同方式替换，对于缺失和低值或高值，使用半经验公式代替。

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引用次数: 0

Suitability of a group of spheroids with a lognormal shape distribution for modeling the scattering and polarimetric properties of irregular particles 一组具有对数正态分布的球体用于模拟不规则粒子的散射和极化特性的适用性

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2025-11-05 DOI: 10.1016/j.jqsrt.2025.109732

Jie Luo , Yangyang Ma , Miao Hu , Congcong Li , Hongjin Li , Xiulin Geng , Meihua Bi , Xuefang Zhou

The morphology of certain atmospheric particles, such as dust, is highly complex, yet remote sensing retrieval methods often employ simplified morphological representations. extensive research has demonstrated that particle morphology significantly influences optical properties, it remains uncertain whether a set of simple models can represent the optical properties of more complex particles. Based on scattering matrices of irregularly shaped model particle ensembles, we assume a lognormal distribution of aspect ratios and invert for the optimal spheroidal particle ensemble to evaluate its ability to replicate the optical and polarimetric properties of particles with more intricate and irregular morphologies. This work compares the performance of both the best-fit single spheroid and the best-fit spheroidal ensemble in simulating the scattering matrix of irregular particles. Our findings indicate that the suitability of the spheroidal-based simulation of the scattering matrix is significantly affected by different shapes. Additionally, the applicability of the spheroidal ensemble is investigated in the context of simulating satellite polarimetric observations, using a vector radiative transfer model with irregular particles as the reference. Results reveal that the normalized radiance simulated by the optimal spheroidal ensemble can deviate by approximately 6% from that of irregular particles, while differences in the polarized bidirectional reflectance factor (pBRF) and the degree of linear polarization (DoLP) range from –0.0015 to 0.0015 and –0.03 to 0.06, respectively. Moreover, the distribution of the best-fit aspect ratios for irregular particles of varying shapes is analyzed. This study provides valuable insights for employing simplified models to assess uncertainty sources in remote sensing applications.

某些大气粒子（如尘埃）的形态非常复杂，但遥感检索方法通常采用简化的形态表示。大量的研究表明，粒子的形态对光学性质有显著的影响，但一组简单的模型能否代表更复杂的粒子的光学性质仍然是不确定的。基于不规则形状模型粒子系的散射矩阵，我们假设长宽比为对数正态分布，并对最佳球形粒子系进行反演，以评估其复制更复杂和不规则形态粒子的光学和偏振特性的能力。本文比较了最佳拟合单椭球和最佳拟合椭球系综在模拟不规则粒子散射矩阵中的性能。我们的研究结果表明，不同形状的散射矩阵对基于球体的散射矩阵模拟的适用性有显著影响。此外，在模拟卫星极化观测的背景下，以不规则粒子的矢量辐射传递模型为参考，研究了椭球系综的适用性。结果表明，最优椭球系综模拟的归一化辐亮度与不规则粒子的辐亮度相差约6%，偏振双向反射系数（pBRF）和线偏振度（DoLP）的差异分别在-0.0015 ~ 0.0015和-0.03 ~ 0.06之间。此外，还分析了不同形状的不规则粒子的最佳拟合宽高比的分布。本研究为采用简化模型评估遥感应用中的不确定性源提供了有价值的见解。

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引用次数: 0

Simultaneous estimation of radiance and its sensitivities to radiative properties in a spherical-heterogeneous atmospheric radiative transfer model by Monte Carlo method: Application to Titan 用蒙特卡罗方法同时估计球形非均质大气辐射传输模型中的辐射强度及其对辐射特性的敏感性：在土卫六上的应用

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2025-11-05 DOI: 10.1016/j.jqsrt.2025.109722

Zili He , Sandrine Vinatier , Vincent Eymet , Vincent Forest , Bruno Bézard , Pascal Rannou , Sébastien Rodriguez , Emmanuel Marcq , Richard Fournier , Stéphane Blanco , Nada Mourtaday , Yaniss Nyffenegger-Péré , Sébastien Lebonnois , Anni Määttänen

The study of planetary atmospheres and surfaces depends on integrating radiative transfer modelling with inversion techniques. Traditional radiative transfer models, which assume simplified geometries (e.g., parallel-plan approximation), are limited in accurately capturing the heterogeneous and spherical nature of planetary atmospheres and surfaces, especially in spectral ranges where the scattering effects are important. Numerous modelling strategies are available with full accuracy in the representation of 3D features, but coupling such realistic radiative transfer model with inversion techniques raises challenges in calculation time and gradient assessment. Thanks to the recent active research at the interface between statistical physics and computer graphics, we here tackle these challenges based on the propositions of null-collision (Galtier et al., 2013) and spatial partitioning of extinction-coefficients overestimates (Villefranque et al., 2019). Straightforwardly, these propositions are implemented here for planetary atmospheres and we also provide a slightly modified version of the algorithm that simultaneously estimates the radiance and its gradient with respect to the radiative properties (e.g., absorption coefficients, scattering coefficients and surface reflectivities). Gradient estimation preserves the insensitivity of calculation time to the geometric complexity. The method is applied to Titan. Its performance and limitations are discussed together with the perspectives of being integrated into the inversion routine of planetary data.

对行星大气和地表的研究依赖于将辐射传输模拟与反演技术相结合。传统的辐射传输模型假设了简化的几何形状（例如，平行平面近似），在准确捕捉行星大气和表面的非均匀性和球形特性方面受到限制，特别是在散射效应重要的光谱范围内。许多建模策略都可以完全准确地表示三维特征，但将这种真实的辐射传输模型与反演技术相结合，在计算时间和梯度评估方面提出了挑战。由于最近在统计物理学和计算机图形学之间的界面进行了积极的研究，我们在这里基于零碰撞命题（Galtier等人，2013）和消光系数高估的空间划分（Villefranque等人，2019）来解决这些挑战。直接地说，这些命题在这里适用于行星大气，我们还提供了一个稍微修改的算法版本，同时估计辐射特性（例如，吸收系数，散射系数和表面反射率）的辐射及其梯度。梯度估计保留了计算时间对几何复杂度的不敏感性。该方法适用于泰坦。讨论了它的性能和局限性，并展望了将其纳入行星数据反演程序的前景。

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引用次数: 0

Emulating non-gray gas radiative heat transfer in combustion scenarios by machine learning method 利用机器学习方法模拟燃烧工况下非灰色气体的辐射传热

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2025-11-04 DOI: 10.1016/j.jqsrt.2025.109735

Yujia Sun , Chenxin Lin , Shu Zheng

Thermal radiation plays an important role in combustion systems due to its significant effect on the energy evolution. Radiation modeling in combustion simulations needs expensive computational resources due to high complexity of the radiative transfer equation and highly variations of the spectral radiative properties. Traditional numerical methods for the radiation modeling have many simplified and approximated models, but they are still suffering from the irreconcilable conflict between the accuracy and efficiency. This work investigates the capability of machine learning for predicting radiative heat transfer in combustion scenarios. Two machine learning models, UNet model and Fourier network operator (FNO) model are designed to learn radiative heat transfer directly from the temperature and concentrations fields. Their performances are tested for a turbulent diffusion flame. Results show that both UNet and FNO performs well for emulating the radiative heat source for the considered flame, with relative errors generally smaller than 0.3 %. The two models have similar accuracies. This study demonstrates the feasibility of using UNet and FNO models as surrogate model for non-gray gas radiative heat transfer in combustion system, but they need further investigations for more complex combustion scenarios.

热辐射对燃烧系统的能量演化有重要影响，在燃烧系统中起着重要作用。燃烧模拟中的辐射建模由于辐射传递方程的高度复杂性和光谱辐射特性的高度变异性，需要耗费大量的计算资源。传统的辐射数值模拟方法有许多简化和近似的模型，但仍然存在精度和效率之间不可调和的冲突。这项工作研究了机器学习预测燃烧场景中辐射传热的能力。设计了两个机器学习模型，UNet模型和傅立叶网络算子（FNO）模型，直接从温度和浓度场中学习辐射传热。在紊流扩散火焰中测试了它们的性能。结果表明，UNet和FNO都能很好地模拟所考虑火焰的辐射热源，相对误差一般小于0.3%。这两种模型具有相似的精度。本研究证明了使用UNet和FNO模型作为燃烧系统非灰气体辐射换热的替代模型的可行性，但需要对更复杂的燃烧场景进行进一步的研究。

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引用次数: 0

O2- and air-broadening coefficients in the ν2 and ν5 bands of CH3Br CH3Br ν2和ν5波段的O2-和空气展宽系数

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2025-11-01 DOI: 10.1016/j.jqsrt.2025.109723

I. Majdi , S. Harbaoui , D. Ben Abdallah , J. Salem , Z. Boussetta , F. Kwabia Tchana , X. Landsheere , A. Voute , M. Hochlaf , H. Aroui

In the present work, we measured the O₂-broadening coefficients of the absorption lines in the ν₂ and ν₅ bands of methyl bromide at room temperature (T = 295 K) using a high-resolution Fourier Transform spectrometer. Eight spectra were recorded at pressures ranging from 2.0 to 6.5 Torr for the active gas and from 3 to 90 Torr for the perturber gas. The line shape parameters were obtained by fitting Voigt and Galatry profiles to the measured line shapes, allowing the determination of the O₂-broadening coefficients for the branches over the 1250 – 1622 cm^-1 wavenumbers range. This range covers 1451 measured transitions with 2 ≤ J ≤ 54 and 0 ≤ K ≤ 10. These data, combined with previously measured N₂-broadening coefficients, were used to determine the air-broadening coefficients of the ν₂ and ν₅ bands. Finally, an empirical model was used to fit the broadening coefficients of the two bands. On average, the empirical expression reproduces successfully the measured broadening coefficients.

本文用高分辨率傅立叶变换光谱仪测量了室温（T = 295 K）下甲基溴ν2和ν5波段吸收谱线的o2展宽系数。活性气体在2.0 ~ 6.5托的压力下，摄动气体在3 ~ 90托的压力下，记录了8个光谱。通过将Voigt和galry剖面拟合到测量的线形上，获得了线形参数，从而确定了分支在1250 - 1622 cm-1波数范围内的o2展宽系数。该范围涵盖了1451个2≤J≤54和0≤K≤10的测量跃迁。这些数据与先前测量的n2展宽系数相结合，用于确定ν2和ν5波段的空气展宽系数。最后，利用经验模型对两波段的展宽系数进行拟合。平均而言，经验表达式成功地再现了测量的展宽系数。

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引用次数: 0

Implementation of low stream interpolation technique to accelerate scattering calculations in the 4A/OP radiative transfer model 在4A/OP辐射传输模型中实现低流插值技术以加速散射计算

IF 1.9 3区物理与天体物理 Q2 OPTICS

Journal of Quantitative Spectroscopy & Radiative Transfer

Pub Date : 2025-11-01 DOI: 10.1016/j.jqsrt.2025.109734

Bojan Sic , Elsa Jacquette , Denis Jouglet , Pierre Lafrique , Clemence Pierangelo , Raymond Armante , Olivier Lezeaux , Mahmoud El Hajj

Considering scattering in radiative transfer calculations often leads to extensively long computation times that can be prohibitive, especially in the operational context of satellite missions. Over time, numerous methods were developed to accelerate scattering calculations. In this paper, based and further built upon the work of O’Dell [1], we describe the implementation of the Low-Stream Interpolation acceleration technique in the 4A/OP radiative transfer model. The method’s acceleration relies on the execution of computationally expensive calculations only for representative points, which represent the regions in the gas absorption optical depth space called “bins”. For all other points the calculation is performed at a low accuracy and by subsequent interpolation. We have considered a number of method’s aspects, and introduced various modifications in order to optimise its accuracy and computation time. This includes: a) an extension of the method to Jacobians, b) modifications of bin and sub-bin divisions, c) implementation of automatic binning and its comparison to fixed bins, d) improvement of the computation of representative points, e) improvement of the definition of “significant scattering” used by the method, f) avoiding the redundancy of high-accuracy computation at large gas absorption optical depths, g) optimisations of the method computation domain size and h) evaluations of various possible accelerations of low-accuracy calculations. We applied the method on the MicroCarb O₂ and CO₂ bands in near-infrared and shortwave-infrared over a large variety of geophysical cases and discussed the impacts of the modifications and the overall performance. We confirmed that the Low-Stream Interpolation is a powerful technique to accelerate the scattering calculations and, in our model, it provided relative accuracies on polarised and unpolarised radiances and Jacobians lower than 0.05 % with acceleration of 10–50 times.

在辐射传输计算中考虑散射通常会导致计算时间过长，这可能令人望而却步，特别是在卫星任务的业务范围内。随着时间的推移，发展了许多方法来加速散射计算。本文在O 'Dell[1]的基础上，描述了低流插值加速技术在4A/OP辐射传输模型中的实现。该方法的加速依赖于只对代表性点执行计算昂贵的计算，这些代表性点代表气体吸收光学深度空间中的区域，称为“箱”。对于所有其他点，计算是在低精度和随后的插值执行。我们考虑了许多方法的方面，并引入了各种修改，以优化其精度和计算时间。这包括:a)将该方法推广到雅可比矩阵，b)修改本箱和子箱的划分，c)实现自动分箱及其与固定分箱的比较，d)改进代表性点的计算，e)改进该方法使用的“显著散射”的定义，f)避免在大气体吸收光学深度下高精度计算的冗余。G)方法计算域大小的优化和h)低精度计算的各种可能加速的评估。我们将该方法应用于近红外和短波红外的MicroCarb O2和CO2波段，并讨论了修改后的影响和整体性能。我们证实了低流插值是一种加速散射计算的强大技术，在我们的模型中，它提供了极化和非极化辐射和雅可比比的相对精度低于0.05%，加速度为10-50倍。

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引用次数: 0