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831.
Ki-Young Heo Jeong-Wook Lee Kyung-Ja Ha Ki-Cheon Jun Kwang-Soon Park Jae-Il Kwon 《Natural Hazards》2009,51(1):151-162
High-quality informations on sea level pressure and sea surface wind stress are required to accurately predict storm surges
over the Korean Peninsula. The storm surge on 31 March 2007 at Yeonggwang, on the western coast, was an abrupt response to
mesocyclone development. In the present study, we attempted to obtain reliable surface winds and sea level pressures. Using
an optimal physical parameterization for wind conditions, MM5, WRF and COAMPS were used to simulate the atmospheric states
that accompanied the storm surge. The use of MM5, WRF and COAMPS simulations indicated the development of high winds in the
strong pressure gradient due to an anticyclone and a mesocyclone in the southern part of the western coast. The response to
this situation to the storm surge was sensitive. A low-level warm advection was examined as a possible causal mechanism for
the development of a mesocyclone in the generating storm surge. The low-level warm temperature advection was simulated using
the three models, but MM5 and WRF tended to underestimate the warm tongue and overestimate the wind speed. The WRF simulation
was closer to the observed data than the other simulations in terms of wind speed and the intensity of the mesocyclone. It
can be concluded that the magnitude of the storm surge at Yeonggwang was dependent, not only on the development of a mesocyclone
but on ocean effects as well. 相似文献
832.
A method for estimating the gear shape of a mid-water trawl 总被引:2,自引:0,他引:2
833.
834.
Hyun Hee Kim Seon Ki Park Dusanka Zupanski Milija Zupanski 《Asia-Pacific Journal of Atmospheric Sciences》2010,46(3):317-325
In this study, the maximum likelihood ensemble filter (MLEF) is applied to a tropical cyclone case to identify the uncertainty areas in the context of targeting observations, using the WRF model. Typhoon Sinlaku (2008), from which dropwindsonde data are collected through THORPEX Pacific Asian Regional Campaign (TPARC), is selected for the case study. For the uncertainty analysis, a measurement called the deep layer mean (DLM) wind variance is employed. With assimilation of conventional rawinsonde data, the MLEF-WRF system demonstrated stable data assimilation performance over multiple data assimilation cycles and produced high uncertainties mostly in data-void areas, for the given tropical cyclone case. Dropwindsonde deployment through T-PARC turned out to occur inside or near the weak uncertainty areas that are identified through the MLEF-WRF system. The uncertainty analysis using the MLEF method can provide a guide for identifying more effective targeting observation areas. 相似文献
835.
836.
Large strain similarity solution for a spherical or circular opening excavated in elastic‐perfectly plastic media
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K.H. Park 《国际地质力学数值与分析法杂志》2015,39(7):724-737
This paper deals with the unloading problem of a spherical or circular opening excavated in elastic‐perfectly plastic media with a nonassociated Mohr–Coulomb yield criterion. A large strain similarity solution, using incremental velocity approach, is presented by replacing partial differential equations from stress equilibrium, constitutive law, consistency condition, and displacement equation with first‐order ordinary differential equations. The classical Runge–Kutta method is used to solve the first‐order ordinary differential equations. Comparisons among small and large strain solutions are made using some data sets of soil and rock. The results show that the displacements by large strain similarity solution are smaller than those by exact small strain solution and somewhat larger than those by large strain solution using total strain approach. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
837.
Pore pressure model based on accumulated stress 总被引:2,自引:2,他引:0
838.
839.
The main purpose of the paper is to present a relatively simple, yet realistic, constitutive model for simulations of structured sensitive clays. The proposed constitutive model can simulate 1‐D and isotropic consolidation, and drained and undrained shear response of sensitive structured clay. The proposed sensitive bounding surface model is based on concepts from the modified Cam clay model 8 and bounding surface plasticity 27 , with the addition of a simple degradation law. The key material parameters are M, λ, κ, and ν from the modified Cam clay framework, h from the bounding surface framework to model a smoothed elasto‐plastic transition, and ωv, ωq, and Ssr to model softening associated with destructuration. The model has separate parameters to model destructuration caused by volumetric strain and deviatoric strain. The model is capable of modeling unusual behavior of strain softening during 1‐D compression (i.e., a reduction of effective stress as void ratio decreases). A good match between test results and the model simulation is demonstrated. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
840.