Reappearance of ordered motions in strongly nonlinear Hamiltonian systems     

Tadashi Yokoyama 《Celestial Mechanics and Dynamical Astronomy》1984,33(2):99-109

A strongly nonlinear Hamiltonian system which occurs in Celestial Mechanics is studied by the method of surface of section. The reappearance of ordered motions is observed and the numerical experiments suggest that this phenomenon could be predicted by the criterion of interaction of resonances.  相似文献   

Effects of environmental gradients concerning water qualities on the structure of the phytoplankton community in the coastal sea     

Tetsuo Mukai  Kazuto Takimoto 《Estuarine, Coastal and Shelf Science》1985,20(2):169-181

The effects on the structure of the phytoplankton community of in situ environmental gradients concerning water qualities, formed during the mixing process of coastal with oceanic waters, were investigated on macro scale over a wide area of the Seto Inland Sea, Japan.The community structure of the phytoplankton varied almost constantly along the in situ environmental gradients in the community, which was shown by use of the diversity index rather than a mere listing of the phytoplankton community. These observations were considered to be the result of the direct or indirect response of the phytoplankton community to environmental gradients which occur in situ, which mean a series of variations of the habitat of the phytoplankton community. Their effects were reflected not in biomass but in the structure of the phytoplankton community. It was difficult to establish quantitatively the extent of their effects because of the variability in the degree of the environmental gradients which occur in situ.  相似文献   

Infrared properties of haze particles of Venus     

Sonoyo Mukai  Tadashi Mukai 《Icarus》1981,48(3):482-487

The computed variation of the infrared flux and polarization of Venus as a function of phase angle, based upon multiple-scattering calculations for the cloud model of Kawabata et al. (1980) with an internal heat source, precludes the possibility of sulfuric acid as the composition of the haze particles located above the main cloud. Furthermore, our calculations reveal that the hazticle should have a large absorption coefficient at these wavelengths, i.e, $\text{k(}\text{imaginary part of the complex refractive index}\text{) ? 1.3}\text{at a wavelength}\text{λ = 3.4 μ}\text{m}$. The optical thickness of the haze layer must be about 0.15 at λ = 3.4 μm.  相似文献   

Optical constants of the mixture of ices     

T. Mukai  W. Krätschmer 《Earth, Moon, and Planets》1986,36(2):145-155

The Maxwell-Garnett mixing rule (MG) was applied to estimate the optical constant m ^* of the mixture of ices. A fairly good agreement between the resulting values of m ^* and those of our laboratory measurements suggests that the MG rule becomes a powerful tool to derive the unknown optical constants of natural dirty-ice, when there are no chemical bonds between the guest and host materials. Our results would provide the knowledge of the optical constants of dirty-ice for studies of icy substances on the surface of satellites, cometary nucleus and interplanetary dust grains based on their reflectance spectra.  相似文献   

Propagation of seismic slip from brittle to ductile crust: Evidence from pseudotachylyte of the Woodroffe thrust, central Australia     

Aiming Lin  Tadashi Maruyama  Stallard Aaron  Katsuyoshi Michibayashi  Alfredo Camacho  Ken-ichi Kano 《Tectonophysics》2005,402(1-4):21

The Woodroffe thrust, central Australia, is a > 1.5-km-wide mylonitized shear zone marked by large volumes of mm- to cm-scale pseudotachylyte veins. The pseudotachylytes display typical melt-origin features, including rounded and embayed clasts, spherulitic and dentritic microlites, and flow structures within a fine-grained matrix. Three types of pseudotachylyte are identified on the basis of deformation texture, vein morphology, and host-rock lithology: cataclasite-related (C-Pt), mylonite-related (M-Pt), and ultramylonite-related (Um-Pt). The M-Pt and Um-Pt veins intrude into mylonite and ultramylonite and are themselves overprinted by subsequent mylonitization. These pseudotachylytes contain an internal foliation defined by flattened porphyroclasts and layering of the fine-grained vein matrix, and the foliation is generally oriented parallel to foliation in the surrounding mylonite and ultramylonite. These observations constrain the timing and environment of M-Pt and Um-Pt pseudotachylyte formation to a protracted period of deformation and mylonitization within the ductile regime of the crust. The M-Pt and Um-Pt veins, as well as the host mylonite, are overprinted by cataclasis and multiple generations of late-stage C-Pt veins that were generated in the brittle-dominated regime of the upper crust during uplift and exhumation of the shear zone.The coexistence of multiple generations of voluminous C-Pt, M-Pt, and Um-Pt veins indicates that the pseudotachylyte veins represent a large number of large earthquakes and accompanying seismic slip over an extended period of seismicity on the Woodroffe thrust. The timing and distribution of pseudotachylyte indicate that the earthquakes nucleated at the base of the brittle-dominated seismogenic zone and propagated down through the brittle–ductile transition into the ductile-dominated regime of the crust.  相似文献   

Characterization of a landslide-triggered debris flow at a rainforest-covered mountain region in Brazil     

Cabral  Victor Carvalho  Reis  Fábio Augusto Gomes Vieira  D’Affonseca  Fernando Mazo  Lucía  Ana  dos Santos Corrêa  Claudia Vanessa  Veloso  Vinicius  Gramani  Marcelo Fischer  Ogura  Agostinho Tadashi  Lazaretti  Andrea Fregolente  Vemado  Felipe  Pereira Filho  Augusto José  dos Santos  Claudia Cristina  Lopes  Eymar Silva Sampaio  Rabaco  Lis Maria Reoni  do Carmo Giordano  Lucilia  Zarfl  Christiane 《Natural Hazards》2021,108(3):3021-3043

Natural Hazards - Debris flows represent great hazard to humans due to their high destructive power. Understanding their hydrogeomorphic dynamics is fundamental in hazard assessment studies,...  相似文献   

Impact of climate and land-use changes on hydrological processes and sediment yield—a case study of the Be River catchment,Vietnam     

Dao Nguyen Khoi  Tadashi Suetsugi 《水文科学杂志》2013,58(5):1095-1108

Abstract

The impact of climate and land-use changes on hydrological processes and sediment yield is investigated in the Be River catchment, Vietnam, using the Soil and Water Assessment Tool (SWAT) hydrological model. The sensitivity analysis, model calibration and validation indicated that the SWAT model could reasonably simulate the hydrology and sediment yield in the catchment. From this, the responses of the hydrology and sediment to climate change and land-use changes were considered. The results indicate that deforestation had increased the annual flow (by 1.2%) and sediment load (by 11.3%), and that climate change had also significantly increased the annual streamflow (by 26.3%) and sediment load (by 31.7%). Under the impact of coupled climate and land-use changes, the annual streamflow and sediment load increased by 28.0% and 46.4%, respectively. In general, during the 1978–2000 period, climate change influenced the hydrological processes in the Be River catchment more strongly than the land-use change.