• International Journal of High-Rise Buildings
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• v.10 no.2
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• pp.137-147
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• 2021

The principle of energy dissipation technology is to dissipate or absorb the seismic energy input through the deformation or velocity change of dampers installed in the main structure of high-rise buildings, so as to reduce the seismic response of the buildings. With the development of energy dissipation technology, recognized as an effective and new measurement for reducing seismic effects, its application in high-rise buildings has become more and more popular. The appropriate energy dissipation devices suitable for high-rise buildings are introduced in this paper. The effectiveness of energy-dissipation technology for reducing the seismic response of high-rise buildings with various structural forms is demonstrated with a number of actual examples of high-rise buildings equipped with various energy dissipation devices.

• Journal of fish pathology
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• v.15 no.2
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• pp.65-75
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• 2002

This study was performed to know the effects of stress induced by the daily fluctuation of water temperture from 18$^{\circ}C$ to 25$^{\circ}C$ up and down for 30 days on the defence mechanism of olive flounder. Puralichthys olivaceus. To make clear the temperature stress on the defense mechanism of the tested fish. several factors of immune response such as counting of leucocyte appearance in peripheral blood, phagocytic activity in whole blood cells, nitroblue tetrazolium(NBT) reduction, chemiluminescence(CL) response, and lysozyme activity were investigated at 28 days after giving the change of water temperature. The fish was controlled under the none feeding condition during experimental period. Mortality of the tested fish was rapidly increased up to 22% within the first one week of the experimental period without any additional stress factors. The number of neutrophil of peripheral blood in the tested group was significantly higher than the control group at the 2nd week. but the number of lymphocyte was significantly lower than the control group at the 1st and 3rd day of the experimental period. respectively. In the NBT reduction test, the activity of macrophage in the control group fish was the highest on the 7th day while that in the tested group was on the 3rd day. Also. the phagocytosis of tested group against formalin killed cells was retarded compared with the control. CL response of the tested group was significantly lower from 2nd to 5lh day of the experimental period than the control. 'The lysozyme activity of tested group was remained higher during the experimental period than the control. Even though the tested fish showed different results in some non-specific factors of immune respceses between tested and control group fish, olive flounder seems highly adaptable in repealed water temperature change in condition after one week under the given temperature fluctuation range.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.5
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• pp.23-30
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• 2018

Recently, there are highly interests on structural damping to improve resistance of seismic and wind. It has been frequently used hysteresis damping devices made of steel because of economic efficiency, construction, and maintenance. This paper presents the effective reduction of seismic response by using Kagome damping system(SKDS) in rahmen system apartment building. The proposed system is designed to be activated by the relative displacement between the building and the stairs. It is performed nonlinear dynamic analysis to review the effects of earthquake response reduction for the 20-stories rahmen framed apartment building. In the analysis of the SKDS system, the reduction of maximum response displacement, maximum response acceleration and layer shear force are compared with the seismic design, and the result show that allowable story displacement is satisfied with Korean Building Code (KBC 2016).

• KIPS Transactions on Software and Data Engineering
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• v.10 no.7
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• pp.263-270
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• 2021

Reinforcement learning(RL) is the method to find an optimal policy through training. and it is one of popular methods for solving lifesaving and disaster response problems effectively. However, the conventional reinforcement learning method for disaster response utilizes either simple environment such as. grid and graph or a self-developed environment that are hard to verify the practical effectiveness. In this paper, we propose the design of a disaster response RL environment which utilizes the detailed property information of the disaster simulation in order to utilize the reinforcement learning method in the real world. For the RL environment, we design and build the reinforcement learning communication as well as the interface between the RL agent and the disaster simulation. Also, we apply the dimension reduction method for converting non-image feature vectors into image format which is effectively utilized with convolution layer to utilize the high-dimensional and detailed property of the disaster simulation. To verify the effectiveness of our proposed method, we conducted empirical evaluations and it shows that our proposed method outperformed conventional methods in the building fire damage.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.34 no.2
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• pp.101-111
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• 2021

In general, several computational resources are required to perform multiple-loading transient response analyses. In this paper, we present the procedure for multiple-loading transient response analysis using the Krylov subspace model order reduction and Newmark's time integration scheme. We utilized ANSYS MAPDL, Python, and ANSYS ACT to automate the transient response analysis procedure in the ANSYS Workbench environment and studied several engineering numerical examples to demonstrate the feasibility and efficiency of the proposed approach.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.10a
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• pp.185-189
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• 2009

It is very important to control the vibration transmitted from external utilities and the transient response due to the internal sources for the precision equipment, which is very sensitive to the vibration environment. The anti-vibration tables that use air springs have been widely used due to their excellent isolation performance, but the systems with high flexibility have the critical problem of large transient response by the impulsive force of the moving mass in operation of the equipment. In this paper, the hybrid vibration control system is proposed, which is combined the air springs with the semi-active MR dampers in order to satisfy the performances of isolation and vibration reduction simutaneously.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2015.07a
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• pp.179-180
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• 2015

The variety of organic and inorganic pollutants are introduced to coastal sediment and making highly contaminated due to rapid development of industralization and economic development. Numerous contaminants are release into marine sediment and it significantly affect marine aquatic environment. In the present study stated the optimize the biostimulant ball (BSB) in coastal sedimentand stabilse the heavy metals present in the sediment. The effective variables like BSB size, distance and month variables on Cu stabilization was determined by using Response surface methodology(RSM). The analysis of variance (ANOVA) and coefficient determination (R2) of Cu reduction 0.9610 and maximum stabilisation was obtained in 3cm ball size and 5.5cm distance and 4 month interval time. This result revealed that the BSB in effective for Cu reduction in coastal sediment.

• Wind and Structures
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• v.25 no.4
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• pp.361-379
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• 2017

In view of the importance of the wind-structure interaction for tall and slender structures, an aeroelastic model test of the 610m-high TV tower with a complex and unique structural configuration and appearance carried out successfully. The assembled aeroelastic model of the TV tower with complex shape and structure was designed and made to ensure the similarities of the major natural frequencies and the corresponding mode shapes. The simulation of the atmospheric boundary layer with higher turbulent intensity is presented. Since the displacement and acceleration responses at several measurement sections were directly measured in the wind tunnel test, a multi-mode approach was presented to indirectly estimate the displacement and acceleration responses at arbitrary structural floors based on the measured ones. It can be seen that it is remarkable for the displacement and acceleration responses of the TV tower in the two horizontal directions under wind loads and is small for the dynamic response of the torsional displacement and acceleration.

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.4
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• pp.413-419
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• 1998

A novel order-reduction technique for model predictive control(MPC) is proposed based on the singular value decomposition(SVD) of a pulse response circulant matrix(PRCM) of a concerned system. It is first investigated that the PRCM (in the limit) contains a complete information of the frequency response of a system and its SVD decomposes the information into the respective principal directions at each frequency. This enables us to isolate the significant modes of the system and to devise the proposed order-reduction technique. Though the primary purpose of the proposed technique is to diminish the required computation in MPC, the clear frequency decomposition of the SVD of the PRCM also enables us to improve the robustness through selective excitation of frequency modes. Performance of the proposed technique is illustrated through two numerical examples.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.55 no.2
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• pp.69-75
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• 2006

This paper deals with the optimum design solution on reduction of torque ripple for a Synchronous Reluctance Motor with concentrated winding using response surface methodology. The coupled Finite Elements Analysis (FEA) & Preisach model have been used to evaluate the nonlinear solution. Comparisons are given with characteristics of a SynRM according to the stator winding, slot number, open width of slot, slot depth, teeth width variation in concentrated winding SynRM, respectively. This paper presents an optimization procedure using Response Surface Methodology (RSM) to determine design parameters for reducing torque ripple. RSM has been achieved to use the experimental design method in combination with finite Element Method (FEM) and well adapted to make analytical model for a complex problem considering a lot of interaction of design variables. Moreover, Sequential Quadratic Problem (SQP) method is used to solve the resulting of constrained nonlinear optimization problem.