• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.2
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• pp.234-240
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• 2014

In this paper, the interface matrix of honeycomb composite panel has been derived by the governing equation of a honeycomb sandwich panel. The interface matrix of honeycomb panel is added to the previously developed transfer matrix method, thus analysis of the multi-layered insulation composite panel with honeycomb is accomplished. Furthermore, predictions of sound transmission loss(STL) for the ship's insulation panel with honeycomb and mineral wool are presented. The insulation performance of the honeycomb used for skin of the ship's insulation panel is better than that of 0.35 mm steel panel by 2dB, approximately. Although honeycomb panel has inefficient insulation performance beside steel panel, honeycomb panel achieve improvements in the performance of weight reduction. The surface density of the panel with honeycomb is rather than with steel by $5.2kg/m^2$. It is decrease in weight by 31.7 %.

• International Journal of Aeronautical and Space Sciences
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• v.17 no.4
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• pp.476-490
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• 2016

This paper defines mode shape function of a composite solar panel assumed as Kirchhoff-Love plate for considering a torsional mode of composite solar panel. It then goes on to define dynamic model of a high-agility satellite considering the flexibility of composite solar panel as well as stiffness of a solar panel's hinge using Lagrange's theorem, Ritz method and the mode shape function. Furthermore, this paper verifies the validity of dynamic model by comparing numerical results from the finite element analysis. In addition, this paper performs a dynamic response analysis of a rigid satellite which includes only natural modes for solar panel's hinges and a flexible satellite which includes not only natural modes of solar panel's hinges, but also structural modes of composite solar panels. According to the results, we confirm that the torsional mode of solar panel should be considered for the structural design of high-agility satellite. Finally, we performed optimization of high-agility satellite for minimizing mass with solar panel's area limit using the defined dynamic model. Consequently, we observed that the defined dynamic model for a high-agility satellite and result of the optimal design are very useful not only because of their optimal structural design but also because of the dynamic analysis of the satellite.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.1
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• pp.39-45
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• 2009

The CRT(Cathode Ray Tube) displays have been substituted for FPDs(Flat Panel Displays) such as LCD(Liquid Crystal Display) and PDP(Plasma Display Panel) because they have a convex surface, large volume and heavy weight. The productivity of FPDs is greatly dependent on the area of thin glass panel with $0.6{\sim}0.8mm$ thickness because FPDs are manufactured by cutting a large-scaled thin glass panel with patterns to the required product dimensions. So FPD's industries are trying to increase the area of thin glass Panel. Through FEM(Finite Element Method) analysis and fluid analysis, we developed an non-contact and air-floating conveyor system which consists of transport-module, distributor, horizontal/vertical changer and controller for the 7th generation glass panel (2,200mm in width, 1,870mm in length and 0.7mm in thickness). The design technology developed in this study can be effectively applied to a conveyor system for a larger-scaled thin glass panel.

• Journal of Labour Economics
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• v.32 no.2
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• pp.95-124
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• 2009

In this article, I were trying to analyze the listed manufacturing companies' trend of productivity and the corporate education & training effect after the financial crisis. According to the analysis, the listed manufacturing companies have decreased their productivity since financial crisis, and from such declining trend. jobless growth and a growth without physical and human capital investment has been observed. Furthermore, there is no efficient labor force coordination within the manufacturing industry; In order to analyze the effect of education & training investment on productivity more deeply, I have practiced the dynamic panel data analysis from constructing the micro panel data which consists of company level information 1997~2008. According to the consequences, dynamic panel data analysis solved the problem of the overestimating education & training effect fairly well.

• Journal of the Society of Naval Architects of Korea
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• v.52 no.5
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• pp.380-386
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• 2015

Panel methods are useful tools for analyzing fluid-flow around a wing section. It has the advantage of fast and accurate calculation, compared to other CFD Methods such as RANS solvers. This paper suggests a piecewise linear panel method in order to improve accuracy of existing panel methods by changing the piecewise constant singularity strength to linear singularity strength(for dipole strength). The piecewise linear panel method adopts the linear distribution of singularity strength, while control point is located at the node of each panel. Formulation of the piecewise linear panel method is given, and some calculation results are shown for typical wing sections.

• Journal of Korean Society of Steel Construction
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• v.9 no.4 s.33
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• pp.683-695
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• 1997

This paper presents the shear behavior of panel zone in steel frame piers. The results of loading tests on twenty box connections and three types of analysis model are reported herein. It is indicate that the major cause of the reduction of strength and shear deformation capacity (ductility) is the sectional-area ratio and the shear buckling of panel zone. Based on the results, some new proposals are presented for the evalution of strength and ductility of panel zone. This paper is also discussed the ductility of connections by current design procedure.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.3 no.4
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• pp.276-285
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• 1991

The transient heat transfer characteristics in the radiant heating panel were predicted by numerical analysis. Thermal behaviors of panel, such as temperature distributions in panel and convective and radiative heat fluxes in panel surface with respect to time were obtained. Heating hours per day, rate of energy supplied and maximum temperature differences at panel surface were also compared for several important parameters. The performance and thermal comfort of heating panel were studied and compared for various operating and design conditions such as pipe pitch, pipe location, pipe diameter and flow rate of hot water for the purpose of producing useful data, which can be used for the test and decision of efficient operating condition of the conventional heating systems or the optimal design of the new panel heating systems.

• Journal of the Regional Association of Architectural Institute of Korea
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• v.21 no.4
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• pp.139-146
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• 2019

The purpose of this study is to propose the building design guideline considering photovoltaic panel installation through the analysis of relevant guidelines from home and abroad in terms of building design and solar panel installation. Conclusions can be summarized as followings; Considerations in building design : selection of the site with high solar accessibility, avoidance of the shade from the adjacent building & trees, south facing orientation of solar panel in building design, removal of shade on the solar panel from the part of building itself, load consideration of solar panel & fixing materials, safe passage securement for solar system maintenance, and planning of piping and mechanical room for solar system. Considerations in solar panel installation : harmonizing of solar panel with surrounding environment, unity of solar panel orientation & slope, regular maintenance of solar system, (in case of flat roof installation) solar panel installation afloat over the roof, installation area within the roof floor, and lower than parapet height, (in case of sloped roof installation) solar panel installation parallel with the roof slope, ventilation space securement below the panel, installation area within the roof surface, and similar material installation in empty space.

• Transactions of Materials Processing
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• v.20 no.7
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• pp.512-517
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• 2011

TRB(Tailor Rolled Blank) is an emerging manufacturing technology by which engineers are able to change blank thickness continuously within a sheet metal. TRB door inner panels with required larger thicknesses can be used to support localized high loads. In this study, the aluminum alloy 5J32 TRB sheet is used for a door inner panel application. The TRB material properties were varied by using three heat treatment conditions. In order to predict the failure of the aluminum TRB during simulation, the forming limit diagram, which is used in sheet metal forming analysis to determine the criterion for failure, was investigated. Full-field photogrammetric measurement of the TRB deformation was performed with an ARAMIS 3D system. A FE model of the door inner panel was created using Autoform software. The material properties obtained from the tensile tests were used in the numerical model to simulate the door inner of AA 5J32 for each heat treatment condition. After finite element analysis for the evaluation of formability, a prototype front door panel was manufactured using a hydraulic press.

• Journal of computational fluids engineering
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• v.19 no.4
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• pp.37-44
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• 2014

A detailed satellite panel thermal model composed of more than thousands nodes can not be directly integrated into a spacecraft thermal model due to its node size and the limitation of commercial satellite thermal analysis programs. For the integration of the panel into the satellite thermal model, a reduced thermal model having proper accuracy is required. A thermal model reduction method was developed and validated by using a geostationary satellite panel. The temperature differences of main components between the detailed and the reduced thermal model were less than $1^{\circ}C$ in steady state analysis. Also, the dynamic responses of the detailed and the reduced thermal model show very similar trends. Thus, the developed reduction method can be applicable to actual satellite thermal design and analysis with resonable accuracy and convenience.