• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.23 no.3
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• pp.111-116
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• 1987

The accurate prediction of the ship wave resistance is very important to design ships which operate satisfactorily in a wave environment. Thus, work should continue on development and validation of methods to compute ship wave patterns and wave resistance. Research efforts to improve the prediction of ship waves and wavemaking resistance are categorized in two major areas. First is the development of higher-order theories to take account of the nonlinear effect of the free surface condition and improved analytical treatment of the body boundary condition. Second is the development of direct numerical methods aimed at solving body and free-surface boundary conditions as accurately as possible. A new formulation of the slender body theory for a ship with constant speed is developed by Maruo. It is quite different from the existing slender ship theory by Vossers, Maruo and Tuck. It may be regarded as a substitute for the Neumann-Kelvin approximation. In present work, the method of asymptotic expansion of the Kelvin source is applied to obtain a new wave resistance formulation in fluid of finite depth. It takes a simple form than existing theory.

• Journal of the Society of Naval Architects of Korea
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• v.46 no.6
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• pp.688-698
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• 2009

In this paper, the steady lift force acting on a slender body moving beneath regular wave systems of arbitrary wavelengths and directions of propagation is considered. The momentum conservation theorem and the strip method are used to obtain the hydrodynamic forces acting on the body and affecting its motions on the assumption that the body is slender. In order to obtain the vertical steady force acting on it, or the free surface suction force, the second-order hydrodynamic forces caused by mutual interactions between the components of the first-order hydrodynamic forces are averaged over time. The validity of the method is tested by comparison of the calculated results with experimental data and found to be satisfactory. Through some parametric calculations performed for a typical model, some useful results are obtained as to the depth of submergence of the body, wavelengths, directions, etc.

• The Korean Journal of Food And Nutrition
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• v.17 no.2
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• pp.156-162
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• 2004

This study was performed as a part of comparative biological studies of carotenoid pigment for the unutilized biological products. The content of total carotenoid in the integument of wild catfish were 0.27(${\pm}$0.7) mg％ and composed of 25.8％ zeaxanthin, 9.7％ diatoxanthin and 9.1 ％ cynthiaxanthin as major carotenoid. The content of total carotenoid in the integument of cultured catfish were 0.07(${\pm}$0.03) mg％ which is relatively lower compare to wild catfish and composed of 48.5％ lutein, 13.9％ zeaxanthin and 13.3％ isocryptoxanthin as major carotenoid. The total carotenoid contents of the slender catfish were 0.75(${\pm}$0.25) mg％ which is relatively higher compare to other species of catfishes. The carotenoids were composed of 24.5％ zeaxanthin, 24.1 ％ 7'8'-dihydro-${\beta}$-carotene-4-ol, 17.9％ 7'8'-dihydro-${\beta}$-carotene and 10.8％ 7'8'-dihydro-${\beta}$-carotene-3-01 as major carotenoid and 8.7％ diatoxanthin, 6.7％ cynthiaxanthin and 5.0％ lutein as minor carotenoid. Based on these data, as a comparative studies of carotenoid in integument of siluridae, parasiloxanthin and 7',8'-dihydroparasiloxanthin which are the characteristic carotenoid of catfish from biwa lake in Japan, Slender catfish contained more based on 7',8'-dihydro-${\beta}$-carotene while that of wild and cultured catfishes were not found, indicating that carotenoid pigment of slender catfish depend on their living conditions.

• Structural Engineering and Mechanics
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• v.4 no.4
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• pp.462-465
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• 1996

• Computational Structural Engineering
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• v.29 no.2
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• pp.33-37
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• 2016

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.159.4-159
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• 2003

No Abstract, See Full Text

• Advances in aircraft and spacecraft science
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• v.1 no.3
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• pp.253-271
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• 2014

A linearised buckling analysis of thin-walled beams is addressed in this paper. Beam theories formulated according to a unified approach are presented. The displacement unknown variables on the cross-section of the beam are approximated via Mac Laurin's polynomials. The governing differential equations and the boundary conditions are derived in terms of a fundamental nucleo that does not depend upon the expansion order. Classical beam theories such as Euler-Bernoulli's and Timoshenko's can be retrieved as particular cases. Slender and deep beams are investigated. Flexural, torsional and mixed buckling modes are considered. Results are assessed toward three-dimensional finite element solutions. The numerical investigations show that classical and lower-order theories are accurate for flexural buckling modes of slender beams only. When deep beams or torsional buckling modes are considered, higher-order theories are required.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.129-139
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• 2005

The focused topic according to be slender and longer of cable stayed bridge's main span is as follows (1) Aerodynamic stability (2) Lateral movement of stiffening girder caused by wind force during and after construction (3) Global bucking of stiffening girder caused by axial force Among this, the number 3 has not received much attention in the past due to high buckling safety factor of stiffening girder. However, according to be slender of stiffening girder, the topic of buckling stability of girder is not any more unconcerned subject. The purpose of this paper is to examine the effect of stay cable's nonlinear behavior on the buckling stability of cable-stayed bridge.

• International Journal of High-Rise Buildings
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• v.5 no.1
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• pp.51-62
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• 2016

The concept of introducing viscous damping devices between outriggers and perimeter columns in tall buildings to provide supplementary damping and improve performance, reduce structural costs, and increase available usable area was developed and implemented by Smith and Willford (2007). It was recognized that the relative vertical movement that would occur between the ends of outriggers and columns, if they were not connected, could be used to generate damping. The movements, and correspondingly damping, can potentially be significantly increased by amplifying them using simple "mechanisms". The mechanisms also make it possible to increase the number of available dampers and thus further increase supplementary damping. The feasibility of mechanisms to amplify supplementary damping and enhance structural performance of tall, slender buildings is studied with particular focus on its efficacy in improving structural performance in wind loads.

• Structural Engineering and Mechanics
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• v.63 no.3
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• pp.385-400
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• 2017

This paper presents an experimental study on the behavior of axially-loaded steel RHS (rectangular hollow section) compression members that are partially reinforced along their lengths with welded steel plates. 28 slender column tests were carried out to investigate the effects of the slenderness ratio of the unreinforced member and the ratio of the reinforced length of the member to its entire length. In addition to the slender column tests, 14 stub-column tests were conducted to determine the basic mechanical properties of the test specimens under uniform compression. Test results show that both the compressive strength and stiffness of an RHS member can be increased significantly compared to its unreinforced counterpart even when only the central quarter of the member is reinforced. Based on the limited test data, it can be concluded that partial reinforcement is, in general, more effective in members with larger slenderness ratios. A simple design expression is also proposed to predict the compressive strength of RHS columns partially reinforced along their length with welded steel plates by modifying the provisions of AISC 360-10 to account for the partial reinforcement.