• International Journal of Aerospace System Engineering
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• 제3권1호
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• pp.21-24
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• 2016

In this study, a optimal design on the hood automotive using eco-friendly natural fiber composites is performed. The hood of an automobile is determined by dividing the Inner panel shape through optimization phase to outer panel and inner panel. It was performed to optimize the size of the thickness of the inner panel and the outer panel by applying a flax/epoxy composite materials. The optimized shape was evaluated for weight-lightening, stability and the pedestrian collision safety. Through the resin flow analysis are confirmed to molding possibility judgment of product.

• Structural Engineering and Mechanics
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• 제25권6호
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• pp.637-652
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• 2007

This paper presents stacking sequence optimization of laminated angle-ply cylindrical panel based on natural frequency. Finite element method (FEM) is used to obtain the vibration characteristic of an anisotropic panel using the first order shear deformation theory(FSDT) and genetic algorithm (GA) is used to obtain the optimal stacking sequence of the layers. Cylindrical panel has finite length and arbitrary boundary conditions. The thicknesses of the layers are assumed constant and their angles are specified as design variables. The effect of the number of plies and boundary conditions in the fitness function is considered. Numerical examples are presented for four, six and eight layered anisotropic cylindrical panels.

• 실천공학교육논문지
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• 제13권2호
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• pp.393-403
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• 2021

본 연구의 목적은 훈련 교·강사를 모집단으로 데이터 기반 의사결정을 위한 토대를 마련하고자 직업훈련기관 수준에서의 패널조사 표집설계 방안을 제시하여 지속적이고 체계적인 훈련 교·강사 실태조사의 기초를 제공하는데 있다. 이에 본 연구에서는 체계적인 조사 설계를 위한 요소인 목표 모집단과 표본추출틀을 제안하였으며, 전문가 자문과 실증 자료 분석을 토대로 데이터의 대표성, 자료 수집의 효율성 및 지속가능성 등을 종합적으로 고려하여 표본추출단위, 외층변인과 내층변인을 고려한 표본추출방법 등을 제시하였다. 연구 결과 패널의 단위를 직업훈련기관으로 하여 패널로 선정된 기관과 그 기관에 소속된 훈련 교·강사가 설문조사에 참여할 수 있도록 2단계 층화 비례 표집 방안을 마련하였으며, 이를 바탕으로 패널조사 표본 설계 방안에 대한 시사점을 제시하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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• pp.457-462
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• 2009

In a high speed train, aluminium extruded panel is widely used in floor, side wall and roof structures for high bending stiffness and weight reduction. However, with some inevitable reasons, aluminium extruded panel shows inferior sound insulation performance compared with the flat panel having same weight. Especially, occurrence of local resonance modes in the particular frequency band, is one of the main reason in the deterioration of the sound insulation performance. Local resonance modes are generated in the structure which consists of periodic unit structure, such as the aluminium extruded panel. The local resonance frequency is determined by the specification of the unit structure. In this study, we predict the local resonance frequency band on the aluminium extruded panel used for the high speed train, and investigate how the design modification in the unit structure influences the local resonance frequency band and panel bending stiffness. The purpose of the study is to provide the design information for the effective unit structure in order to improve the sound insulation performance of the aluminium extruded panel.

• 한국공작기계학회논문집
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• 제15권6호
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• pp.88-96
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• 2006

The objective of this research works is to develop back panel dies of PDP TV with a large size. In order to design the geometry of the dies and an initial size of blank optimally, the finite element analysis has been carried out using AUTOFORM V4.2. The conner radius of the upper trimming area and the distance from the outer line of the blank holder to the outer line of the blank have been selected as design parameters to remove the wrinkling of the trimming area. The results of the analyses have been shown that a feasible product without wrinkles and skid lines can be obtained when the conner radius ranges from 6mm to 8mm and the distance lines in the range of 40-60mm. From the proposed design of the dies and an initial blank size, the final die set of the back panel has been successfully manufactured.

• Steel and Composite Structures
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• 제51권3호
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• pp.289-304
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• 2024

The seismic performance of traditional steel frame-shear wall structures was significantly improved by the application of self-centering steel-reinforced concrete (SRC) wall-panel structures in the steel frames. This novel resilience functionality can rapidly restore the structure after an earthquake. The presented steel frame with steel-reinforced concrete self-centering wall-panel structures (SF-SCW) was validated, indicating its excellent seismic performance. The seismic design method based on bear capacity cannot correctly predict the elastic-plastic performance of the structure, especially certain weak floors that might be caused by a major fracture. A four-level seismic performance index, including intact function, continued utilization, life safety, and near-collapse, was established to achieve the ideal failure mode. The seismic design method, based on structural displacement, was proposed by considering performance objectives of the different seismic action levels. The pushover analysis of a six-floor SF-SCW structure was carried out under the proposed design method and the results showed that this six-floor structure could achieve the predicted failure mode.

• 한국강구조학회 논문집
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• 제9권4호통권33호
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• pp.683-695
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• 1997

본 연구는 강제 라멘교각 접합부 panel zone의 전단거동특성에 대하여 검토한 것이다. 여기에서는 접합부 시험체 20개에 대한 재하실험 결과와 3가지의 FEM해석 모델에 대한 결과를 제시 하였다. 이와같은 실험및 해석결과를 비교 검토한 결과, panel zone의 강도와 변형 성능은 단면적비와 전단좌굴등에 의하여 감소하는 경향을 보이고 있음을 알 수 있었다. 따라서 본 연구에서는 이상의 결과를 기초로 panel zone의 강도와 변형성능에 대한 새로운 평가식을 제안하였으며, 또한 기존의 라멘교각 접합부에 대한 변형성능에 관해서 검토하였다.

• 한국군사과학기술학회지
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• 제6권2호
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• pp.35-44
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• 2003

A Decal Panel is developed for the Night Vision Imaging System of XKO-1 aircraft. The Decal Panel is a kind of lighting system kits and is installed on each system switch box in crewstation. The Decal Panel consists of upper panel made of polycarbonate and lower panel which is a printed circuit board. This paper includes the design, manufacture, test and evaluation of Decal Panel in addition to items and conditions of environmental test. Besides it is confirmed the Key for manufacturing a decal panel, is depth of paint, dry time period and frequency, and diffusion material for spreading of light.

• 한국정밀공학회지
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• 제23권4호
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• pp.91-98
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• 2006

A light guide panel (LGP) is an element of the LCD back light unit, which is used for display devices. In this study, the laser marking process is applied to the fabrication of light guide panels as the new fabrication process. In order to obtain a light guide panel which has high luminance and uniformity, four principal parameters such as power, scanning speed, ratio of line gap, and number of line were selected. A Web-based design tool was developed to generate patterns of light guide panel at any location, and the tool may assist the designer to develop optimized patterns. Topcon-BM7 was used for luminance measurement of each specimen with $100mm{\times}100mm$ area. By Taguchi method optimized levels of each parameters were found, and luminance of $3523cd/cm^2$ and uniformity of 92% were achieved using the laser machined BLU.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.638-643
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• 2011

The aluminum soundproofing panel used to the traffic noise reduction will judge with the material to improve because the CO2 emission is greater than other soundproofing panel such as plastic soundproofing panel. Also, if the air-passing soundproofing panel which can endure the fast wind velocity will be developed, it judged that it can reached to the target of low CO2 traffic technology development using the reduction of material cost and the lower consumption of steel. The objective of this study is to improve the soundproofing panel and to develop the air-passing soundproofing panel for the replacement of aluminum sound proofing panel which is more emit CO2 than other soundproofing panel. And, we tried to develop the reduction technology of CO2 emission through the development of air-passing soundproofing panel. At first, the flow and noise simulation were conducted for the purpose of the calculation of wind pressure on soundproofing wall and noise exposure level on receiver points according to the open ratio of air-passing soundproofing panel. And the 1st and 2nd mockup of air-passing soundproofing panel were made, and the design load test were conducted for these mockup.