排序方式： 共有44条查询结果，搜索用时 62 毫秒
41.
Aditya R. Kartadikaria Yasumasa Miyazawa Kazuo Nadaoka Atsushi Watanabe 《Ocean Dynamics》2012,62(1):31-44
An eddy-resolving Indo-Pacific ocean circulation model was applied to highlight the behavior of eddies throughout the Indonesian
seas. The complexity of the topography and coastline at the entrance of the Makassar Strait induce an eddy-type throughflow,
instead of a straightforward flow. A sill and a narrow passage in the Makassar strait creates a barrier and impedes the continuation
of eddies from the Pacific ocean, but the existence of a steep deep basin (>500 m depth) between the Java and Flores seas
indicates a possible area for eddies. Based on our numerical results, we described the presence of a unique eddy structure
north of Lombok Island, which we designated the “Lombok Eddy” and verified it by performing a drifter release field experiment
and reviewing monthly mean climatology data from the World Ocean Atlas 2001 and XBT PX2 track data. NCEP/NCAR reanalysis,
satellite observation data, and mixed layer depth analysis were also used to confirm these processes. By analyzing numerical
simulation results and available temperature datasets, two additional eddies were found. All eddies form primarily due to
eastward local winds correlated with seasonal monsoon winds during the austral summer. These eddies vary synchronously at
an interannual time scale. Together, they are referred to as the Lombok Eddy Train (LET), which affects the surface layer
down to a depth of 60 m, and the intensity of the eddy system is strongly affected by mixed layer depth variability from December
to February. 相似文献
42.
Shape classification of the 40-Hz waveforms obtained by the recently launched AltiKa satellite has been attempted in the paper. Since retracking algorithms suitable for altimeter return echoes based on Brown model are not applicable for the echoes from coastal ocean, specific algorithms are to be devised for such echoes. In the coastal ocean, waveforms display a wide variety of shapes due to varying coastline geometry, and topography. Hence, a proper classification strategy is required for classifying the waveforms into various categories so that suitable retracker could be applied to each category for retrieving the oceanic parameters. The algorithm consists of three steps: feature selection, linear discriminant analysis, and Bayesian classifier. The classification algorithm has been applied to the waveforms in the close proximity of Gujarat coast. Independent validation has been done near the eastern coast of India. Confusion matrices obtained for both the coasts are quite encouraging. Individual examples of classification have been provided for the purpose of illustration. 相似文献
43.
Ganga river basins exposed to active erosional and deformational processes. The recurrence of landslides, floods, and seismic activities makes it more susceptible to deformational activities. The tectonic analysis using geomorphic indices and morphometric parameters will help in determining the hazard-prone area of the river basin. Geomorphic indices and morphometric parameters are calculated to investigate the role of neotectonic activities, as it acts as a controlling factor in the development of landforms in the tectonically active terrains. Neotectonic activities influence the terrain topography, which significantly affects the drainage system and geomorphological setup of the area. In this study, the assessment of active tectonics of study area was determined using Advanced Spaceborne Thermal Emission and Reflection Radiometer(ASTER) Global Digital Elevation Model(GDEM) based on Geomorphic Indices(Stream Length Gradient index, Hypsometric integral, Asymmetry factor, Basin shape, Valley floor width to Valley height ratio, Mountain front sinuosity index) cumulatively with Linear, Areal and Relief morphometric parameters on 27 delineated basins of the study area. The combined classification of Relative Tectonic Activity Index(Iat) and morphometric parameters of 27 basins categorized all the zones into four different classes:Class 1 – Very High(1.97; 410 km~2); Class 2 – High(1.97 – 2.05; 275 km~2); Class 3 – Moderate(2.05 – 2.21; 273 km~2),and Class 4 – Low(2.21; 299 km~2). The basins with tectonic activities have a consistent relationship with structural disturbances, basin geometry, and field studies. The tectonically active zonation of a part of Ganga basin using geomorphic indices and morphometric parameters suggest that it has significant influence of neotectonic activities in a part of Ganga basin. 相似文献
44.
We study the physical behavior of a five dimensional non-static spherically symmetric cosmological models in the presence of massive strings in the framework of \(f(R,T)\) gravity proposed by Harko et al. (Phys. Rev. D 84:024020, 2011). Here \(R\) is the Ricci scalar and \(T\) is the trace of the stress energy tensor and the fifth dimension is not observed because it is compact. We solve the field equations (i) using a relation between the scale factors given by Samantha and Dhal (Int. J. Theor. Phys. 52:1334, 2013) and (ii) equations of state for string models. The models obtained correspond to \(p\)-string, geometric string and massive string models in this modified theory in five dimensions. Cosmological parameters of the models are determined and their dynamical properties are discussed. 相似文献