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The general formulations for spectral directional emissivity and spectral bi-directional reflectivity are analyzed by using Fresnel's formula and Snell's law in rough sea surface which is simulated by wave facets, whose slopes are changing according to the isotropic Gaussian distribution with respect to surface wind. Then, shadowing effect is taken into account in both emission and reflection of sea surface. On this basis, the mathematic expression is obtained for spectral radiance of rough sea surface, in which the radiance of rough sea surface is considered as a composition of self-emission, reflection of sky and reflection of sun. Finally, calculations for infrared radiance of rough sea surface in bands of 3-5 μm and 8-12 μm are given to illustrate their significant different, which are caused mostly by the dispersion of sun radiation. 相似文献
43.
城市道路沥青混凝土路面裂缝分析 总被引:4,自引:0,他引:4
归纳总结了城市道路沥青混凝土路面常见裂缝的类型,结合实际案例分析了裂缝产生的原因,并提出防治路面裂缝的具体措施。 相似文献
44.
Neural networks (NNs) for the inversion of chlorophyll concentrations from remote sensing reflectance measurements were designed and trained on a subset of the SeaBAM data set. The remaining SeaBAM data set was then applied to evaluating the performance of NNs and compared with those of the SeaBAM empirical algorithms. NNs achieved better inversion accuracy than the empirical algorithms in most of chlorophyll concentration range, especially in the intermediate and high chlorophyll regions and CaseⅡ waters. Systematic overestimation existed in the very low chlorophyll (<0.031 mg/m3) region, and little improvement was obtained by changing the size of the training data set. 相似文献
45.
46.
Yu Liu Zhaoran Hao Haigang Jiang Yajun Liu Yafei Wang Hua Tan Guohua Xie 《Tetrahedron》2018,74(3):425-432
Two novel dendrimer-like blue-emitting dinuclear cyclometalated iridium (III) complexes, namely (DNaTPA)2DBF(FIrpic)2 and (DPyTPA)2DBF(FIrpic)2, have been successfully synthesized and characterized. In which FIrpic is an iridium (III) bis[(4,6-difluorophenyl)pyridinato-N,C2′]picolate blue-emitting phosphorescent chromophore core, DBF is a 2,7-diphenyl-9H-fluorene bridging core, DNaTPA and DPyTPA are deep blue-emitting fluorescent chromophores composed by rigid high-triplet-energy dendrons of triphenylamine-functionalized naphthalene or pyrene units, and the peripheral dendrons are connected with the ancillary ligand of the emitting core through nonconjugated ether linkage. Their photophysical, thermal, electrochemical, as well as electrophosphorescent properties were primarily studied. Both iridium (III) complexes exhibit high efficient blue emission in solution (38.5% and 19.2%) and a typical FIrpic emission in 1,3-bis(N-carbzolyl)benzene (mCP) matrix (27.0% and 24.1%). Simple bilayer phosphorescent organic light-emitting diodes (PHOLEDs) with a configuration of ITO/PEDOT:PSS/mCP:dopants/TmPyPB/Liq/Al achieved high efficiencies of 12.96 cd/A for current efficiency (CE), 6162 cd/m2 for brightness, 6.22% for external quantum efficiency (EQE), and 3.13 lm/W for power efficiency (PE) with Commission International de L'Eclairage (CIE) coordinates of (0.19 ± 0.01, 0.35 ± 0.02) at only 2 wt% blend of (DNaTPA)2DBF(FIrpic)2. (DPyTPA)2DBF(FIrpic)2-doped devices also reach efficiencies of (9.14 cd/A, 7167 cd/m2, 4.41%, 2.61 lm/W) at the same doping concentration. The results demonstrate that the introduction of dendritic blue-emitting fluorescent chromophore grafted into the blue phosphorescent chromosphere core through nonconjugated linkage is an efficient way to achieve high-efficiency sky-blue emission. 相似文献
47.
Yuan Tian Hong Chen Shufan Ji Zhengping Han Haigang Lian Xiaojun Wen 《Optical and Quantum Electronics》2014,46(6):769-777
Using the quantum teleportation, a broadcasting multiple blind signature scheme is proposed. Different from classical multiple signature and current quantum signature schemes, which could only deliver either multiple signature or unconditional security, our scheme guarantees both by adopting quantum key preparation, quantum encryption algorithm and quantum teleportation. Our proposed scheme has the properties of multiple signature, blindness, non-disavowal, non-forgery and traceability. To the best of our knowledge, we are the first to propose the broadcasting multiple blind signature using the quantum teleportation. 相似文献
48.
A measurement scheme carried out in a tank is designed to obtain the compressionaland shear-wave velocities of a large elastic material.A hydrophone is used to receive the high frequency acoustic signals which penetrate the tested material,in order to determine the transmission time from the source to the hydrophone,the transmission time is also calculated according to the ray acoustic theory in layered media.A cost function is built based on the measured and the calculated transmission time,then the compressional- and shear-wave velocities can be obtained using the optimization algorithm.Compared with the traditional measurement scheme,this approach can not only get the 2 kinds of sound velocities in the tested material at the same time,but also keep the integrality of the tested material.With the proposed measurement system,the uncertainty of measurement results is less than 3.5%. 相似文献
49.
In this paper, we establish the existence theorem for the exterior Dirichlet problems for a class of fully nonlinear elliptic equations, which are related to the eigenvalues of the Hessian matrix, with prescribed asymptotic behavior at infinity. This extends the previous results on Monge–Ampère equation and k-Hessian equation to more general cases, in particular, including the special Lagrangian equation. 相似文献
50.
针对浅海Pekeris环境下声矢量场的干涉特征,基于简正波理论分析了在频率-距离域上声强谱、质点振速自谱、复声强谱和波阻抗谱干涉结构的形成机理,探讨了对干涉结构的波导不变量表征,并进行了宽带辐射声场干涉结构的海上测量试验。仿真研究和海试数据分析均表明,在频率-距离域上,上述4类物理量都会呈现稳定的、可用波导不变量β表征的干涉结构,而复声强独有的纯干涉分量更能体现波导的干涉效应。最后引入多尺度线性滤波器对海试实测LOFAR图进行处理,处理结果表明该滤波器可有效地增强干涉特征,更利于检测和提取干涉图案中的条纹信息。 相似文献