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51.
In the present paper, with the aid of invariance principles in connection with the scattering matrix, we get the exact solution of diffuse reflection and transmission problems by finite inhomogeneous, anisotropically scattering atmospheres bounded by reflecting sufaces. On making use of the reflection and transmission integral operators, we show how to obtain the non-linear integro-differential equations for these operators, which do not depend on the initial condition. Then, we have a system of the required integro-differential equations for the scattering and transmission functions. The obtained result is new, so far as we know. Finally, using the scattering matrix, we reduce the diffuse reflection and transmission problems for planetary atmospheres with reflecting surfaces to the standard diffuse reflection and transmission problems.Supported by the National Science Foundation under Grant No. GP29049 and the Atomic Energy Comminission, Division of Research under Contract No. AT(40-3)-133, Project 19. 相似文献
52.
Hiromichi Ueno 《Journal of Oceanography》2013,69(2):277-283
Hydrographic data measured for 50 years along Line P between the North American west coast and mid Gulf of Alaska as well as data from profiling float observations were analyzed to study the formation and variation of temperature inversions in the eastern subarctic North Pacific. Remarkable decadal to inter-decadal variation was observed in the magnitude of temperature inversions. This variation was mostly attributed to the variation of southward Ekman transport, eastward geostrophic transport, and surface cooling. 相似文献
53.
In an attempt to examine whether the spectroscopic Doppler method with an iodine cell (which is known to be successful for
precise radial-velocity determinations in stellar astronomy) could be effective for investigating the solar differential rotation,
we carried out intensive observations to collect spectra at a large number of points on the solar disk by using the Domeless
Solar Telescope along with the horizontal spectrograph of the Hida Observatory. Having converted the resulting line-of-sight
velocity component into the angular rotational rate (ω), we derived a differential rotation law, wsidereal (deg day-1) = 14.03 (±0.06)-1.84 (±0.57) sin2y-1.92 (±0.85) sin4y\omega_{\mathrm{sidereal}}\; (\mathrm{deg}\,\mathrm{day}^{-1}) =14.03 (\pm0.06)-1.84 (\pm0.57) \sin^{2}\psi-1.92 (\pm0.85) \sin^{4}\psi (ψ: heliographic latitude), which is reasonably consistent with other spectroscopic determinations published so far. Our analysis
also revealed several practical points to note for successful application (e.g., exclusion of those data that are not well distant from the meridian; mutual data subtraction/averaging for symmetric counterparts
at the eastern and western hemisphere). Considering its easiness and cheapness, this iodine-cell-featured spectroscopic method
may be regarded as an effective and practical tool for studying the differential rotation of the Sun. 相似文献
54.
Sachihiko Itoh Ichiro Yasuda Hiromichi Ueno Toshio Suga Shigeho Kakehi 《Journal of Oceanography》2014,70(3):211-223
Regeneration of a warm anticyclonic ring as a result of interaction with cold water masses was observed within the western subarctic gyre of the North Pacific. Satellite, profiling float, and shipboard observations revealed that a warm-core ring originated from the Kuroshio Extension, propagating northeastwards, entrained cold and fresh water masses from the coastal area of Hokkaido, which are typically recognized within the ring as water that is colder than 2.5 °C. The potential temperature and planetary contribution of potential vorticity of the cold water in the coastal area of Hokkaido were <2 °C and 15 × 10?11 m?1s?1, respectively, suggesting that it originated from the Sea of Okhotsk. After the intrusion, the warm core of the ring cooled, freshened, and contracted, while the outer and lower parts became occupied by the cold and fresh water; however, even after the cooling, the positive surface elevation and downward depression of the main pycnocline, typical of an anticyclonic ring, were still evident. The ring continued to propagate northeastwards, with the main part of its structure occupied by the cold water, but changed its direction of travel from northwest to west-southwest 8 months after the cold-water event, and was finally absorbed into another warm-core ring. It is suggested that these anticyclonic rings, which transported and mixed warm and cold water masses, play important roles in the cross-gyre exchange of subtropical and subarctic waters in the North Pacific. 相似文献
55.
Makoto Taguchi Tetsuya Fukuhara Masahiko Futaguchi Mitsuteru Sato Takeshi Imamura Kazuaki Mitsuyama Masato Nakamura Munetaka Ueno Makoto Suzuki Naomoto Iwagami George L. Hashimoto 《Icarus》2012,219(1):502-504
Mid-infrared images of almost the entire Venus nightside hemisphere obtained by the Longwave Infrared Camera (LIR) onboard Akatsuki on December 9 and 10, 2010 reveal that the brightness temperature of the cloud-top ranges from 237 K in the cold polar collars to 243 K in the equatorial region, significantly higher than the values obtained by Venera 15. Other characteristic features of the temperature distributions observed are zonal belt structures seen in the middle and low latitudes and patchy temperature structures or quasi-periodic streaks extending in a north–south direction in the northern middle latitudes and southern low latitudes. 相似文献
56.
57.
In order to facilitate the computations of the intensities of radiation reflected and/or transmitted by plane-parallel, vertically inhomogenous, scattering-absorbing media, we carry out the optical thickness integrations of the Cauchy systems (normally referred to as Invariant Imbedding Equations) for reflection and transmission functions originating from the first three orders of scattering: the medium in question is represented by a stack of a certain number of homogeneous slabs, each of which is characterized by a constant single scattering albedo and a constant phase function together with the optical thickness.The results are a set of recurrence formulae involving only the angular intergrations, a convenient feature for numerical computations, and should prove useful particularly for finding approximate values of the high frequency Fourier coefficients of reflection and transmission functions of inhomogeneous media or efficiently initializing the solution for a thin layer to perform rigorous multiple scattering computations by means of other techniques such as the Doubling-Adding method. 相似文献
58.
Contamination by organochlorine compounds in sturgeons from Caspian Sea during 2001 and 2002 总被引:2,自引:0,他引:2
Kajiwara N Ueno D Monirith I Tanabe S Pourkazemi M Aubrey DG 《Marine pollution bulletin》2003,46(6):741-747
Organochlorine compounds (OCs) were determined in the five species of sturgeons collected from coastal waters of Caspian Sea in Kazakhstan, Azerbaijan, Turkmenistan and Iran during 2001 and 2002 to understand their status of contamination and accumulation features. Among OCs examined, concentrations of DDTs (DDT and its metabolites) were predominant in all the sturgeon samples with concentrations ranging from 73 to 31,000 ng/g on lipid weight basis, followed by PCBs, CHLs, HCHs, HCB, dieldrin, TCPMOH, and heptachlor epoxide in order. The concentrations of OCs in beluga (Huso huso) were the highest among all the five species. When comparing residue levels among same species, OC residues were highest in sturgeons from Azerbaijan and Kazakhstan and lowest in Turkmenistan. However, the concentrations of HCHs, dieldrin, and heptachlor epoxide in sturgeons showed less geographical variability. 相似文献
59.
A complete set of transfer equations required for the order-of-scattering analysis of partially polarized radiation in inhomogeneous, anisotropically scattering atmospheres is provided. The equations have been derived for both a local study using the radiative transfer equation and its associated auxiliary equation for the source-matrix, and a global study in terms of the scattering and transmission matrices; they account for the polarity of the scattering medium. Their derivations for the finite order scattering and the finitely cumulative scattering, in particular, have yielded important new equations expressing the invariance principles and the integro-differential recurrences for the scattering and transmission matrices. These novel expressions contain as a special case Bellmanet al's (1972) equations for the simpler case of isotropic scattering of unpolarized light in homogeneous atmospheres. 相似文献
60.
We present a new method for the automatic identification and classification of dynamic Hα dark features found in time series of full-disk solar images at three Hα wavelengths (center, and ± 0.8 Å). The simultaneous Hα observations are obtained by the multi-channel Flare Monitoring Telescope (FMT) at Hida Observatory. The program was developed in order to replace the present visual detection and classification of the phenomena. Usually, an obvious dark feature found in the Hα ?0.8 Å observations probably corresponds to some phenomenon such as a surge or chromospheric network enhancement, or filament activity. Thus, one of our aims in this program is to distinguish each phenomenon by its own properties and key parameters. We optimized the threshold values of the key parameters such as the area and darkness of the transiently darkening features in Hα ?0.8 Å so that the computer can reasonably identify surges and filament activations. In comparison, for a 7-day observation period, the number of dark events detected by the program contains 89% of the events recognized visually. However, 10 times more events are detected automatically. The missing events are mainly caused by the deletion of data with poor visibility. It is found that the dark events can be identified with more precise starting and ending times by a machine than by a human. Some statistical studies of surges or other activities can be carried out based on the computer-produced database. With some modifications the program can be applied to monitor real-time dynamic features on disk, including flare ribbons. 相似文献