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101.
Lee Donggil Oh Wooseok Gim Byeong-Mo Lee Jung Suk Yoon Euna Lee Kyounghoon 《Ocean Science Journal》2019,54(4):573-579
Ocean Science Journal - Efficient fish aggregation systems are essential for catching chub mackerel (Scomber japonicus), which is a major target of purse seine fisheries in South Korea. To aid the... 相似文献
102.
Modeling input errors to improve uncertainty estimates for one-dimensional sediment transport models
Jung Jeffrey Y. Niemann Jeffrey D. Greimann Blair P. 《Stochastic Environmental Research and Risk Assessment (SERRA)》2018,32(6):1817-1832
Stochastic Environmental Research and Risk Assessment - Bayesian methods have recently been applied to one-dimensional sediment transport models to assess the uncertainty in model predictions due... 相似文献
103.
Ocean Science Journal - This study sought to examine the characteristics and patterns of marine algae community changes in Wangdol-cho in order to establish a theoretical basis for the development... 相似文献
104.
DeWachter E. Murk A. Straub C. Haefele A. Soohyun Ka Jung Jin Oh Kampfer N. 《Geoscience and Remote Sensing Letters, IEEE》2009,6(1):3-7
The Stratospheric WAter vapor RAdiometer (SWARA) is a microwave radiometer designed for ground-based measurements of water vapor (H2O) in the middle atmosphere (20 to 80 km), including the stratosphere and mesosphere. The instrument is operating in a noncryogenic balancing calibration mode. Since its deployment, features have been observed in the spectrum which can be attributed to resonant variations of the antenna pattern of the corrugated horn. This paper presents copolar and crosspolar antenna pattern measurements of two sister antennas of the SWARA horn, as well as water vapor measurements from both antennas on the ground-based microwave radiometer MI ddle Atmospheric WAter vapor RA diometer. We show that small irregularities in the frequency spectrum at the -20-dB level are visible in the copolar pattern, which, due to the balancing operation scheme used for the radiometer, lead to features in the spectrum that have the same or even higher brightness temperature as the line of interest. 相似文献
105.
The present paper is Part I of a series of three papers prepared by the authors on the methods useful for ultimate limit state assessment of marine structures, that have been developed in the literature during the last few decades. It is considered that such methods are now mature enough to enter day-by-day design and strength assessment practice. The aims of the three papers are to conduct some benchmark studies of such methods on ultimate limit state assessment of (unstiffened) plates, stiffened panels, and hull girders of ships and ship-shaped offshore structures, using some candidate methods such as ANSYS nonlinear finite element analysis (FEA), DNV PULS, ALPS/ULSAP, ALPS/HULL, and IACS common structural rules (CSR) methods. As an illustrative example, an AFRAMAX-class hypothetical double hull oil tanker structure designed by CSR method is studied. In the present paper (Part I), the ultimate limit state assessment of unstiffened plates under combined biaxial compression and lateral pressure loads is emphasized using ANSYS, DNV PULS, and ALPS/ULSAP methods, and their resulting computations are compared. Part II will deal with methods for the ultimate limit state assessment of stiffened panels under combined biaxial compression and lateral pressure using ANSYS, DNV PULS, and ALPS/ULSAP methods, and Part III will treat methods for the progressive collapse analysis of the hull structure using ANSYS, ALPS/HULL, and IACS CSR methods. 相似文献
106.
107.
This paper presents the implementation details of a real‐time pseudodynamic test system that adopts an implicit time integration scheme. The basic configuration of the system is presented. Physical tests were conducted to evaluate the performance of the system and validate a theoretical system model that incorporates the dynamics and nonlinearity of a test structure and servo‐hydraulic actuators, control algorithm, actuator delay compensation methods, and the flexibility of an actuator reaction system. The robustness and accuracy of the computational scheme under displacement control errors and severe structural softening are examined with numerical simulations using the model. Different delay compensation schemes have been implemented and compared. One of the schemes also compensates for the deformation of an actuator reaction system. It has been shown that the test method is able to attain a good performance in terms of numerical stability and accuracy. However, it has been shown that test results obtained with this method can underestimate the inelastic displacement drift when severe strain softening develops in a test structure. This can be attributed to the fact that the numerical damping effect introduced by convergence errors becomes more significant as a structure softens. In a real‐time test, a significant portion of the convergence errors is caused by the time delay in actuator response. Hence, a softening structure demands higher precision in displacement control. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
108.
Yuan‐Sen Yang Shang‐Hsien Hsieh Keh‐Chyuan Tsai Shiang‐Jung Wang Kung‐Juin Wang Wei‐Choung Cheng Chuan‐Wen Hsu 《地震工程与结构动力学》2007,36(15):2291-2306
An Internet‐based framework, named Internet‐based Simulation for Earthquake Engineering (ISEE) was developed to facilitate collaborative earthquake engineering experiments performed by multiple laboratories in a network environment. One of the approaches in the ISEE framework, named Database Approach, offers an easy way to perform multi‐site networked collaborative pseudo‐dynamic experiments. The Database Approach uses the Structured Query Language (SQL), a common and standardized computer language used in database management systems, for inter‐laboratory communications. Using the SQL protocol, it is easy to monitor the experiments' progress, access the data, as well as develop additional programs to expand the functions for a networked experiment. This approach offers consistency and durability of selected experimental data both during and after experiments. Two networked pseudo‐dynamic experiments were conducted to demonstrate the feasibility and expansibility of the Database Approach in ISEE. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
109.
3D magnetotelluric modelling including surface topography 总被引:9,自引:0,他引:9
Myung Jin Nam Hee Joon Kim Yoonho Song Tae Jong Lee Jeong-Sul Son Jung Hee Suh 《Geophysical Prospecting》2007,55(2):277-287
An edge finite‐element method has been applied to compute magnetotelluric (MT) responses to three‐dimensional (3D) earth topography. The finite‐element algorithm uses a single edge shape function at each edge of hexahedral elements, guaranteeing the continuity of the tangential electric field while conserving the continuity of magnetic flux at boundaries. We solve the resulting system of equations using the biconjugate gradient method with a Jacobian preconditioner. The solution gives electric fields parallel to the slope of a surface relief that is often encountered in MT surveys. The algorithm is successfully verified by comparison with other numerical solutions for a 3D‐2 model for comparison of modelling methods for EM induction and a ridge model. We use a 3D trapezoidal‐hill model to investigate 3D topographic effects, which are caused mainly by galvanic effects, not only in the Zxy mode but also in the Zyx mode. If a 3D topography were approximated by a two‐dimensional topography therefore errors occurring in the transverse electric mode would be more serious than those in the transverse magnetic mode. 相似文献
110.
The characteristics of four wet deposition schemes widely used in dust modeling studies are examined within the framework of a regional scale dust model. Since these schemes are based on different formulations, the scavenging coefficients of them deviate by a factor of 103 depending on precipitation rate and particle size. The four schemes coupled with the dust model are applied to simulate a 2002 Asian dust event. The corresponding wet deposition patterns and scavenging efficiencies are compared. It is found that apart from the scheme derived from scavenging coefficient measurements, the other three schemes give similar wet deposition patterns although their scavenging efficiencies are different depending on the particle-size range. The results suggest that the performances of these schemes are affected by the particle size distribution of the dust emission, together with the model's performance of precipitation prediction. 相似文献