• 품질경영학회지
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• 제41권4호
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• pp.601-610
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• 2013

Purpose: The purpose of this paper is to analyze the relationship between R&D investment and growth rate of manufacturing firms in Incheon. Methods: The balanced panel data of 246 firms which have existed for the period 2001-2012 are constructed. As a method of analysis, fixed effects panel data model is used. Results: There is a one year lag in the relationship between R&D intensity and the subsequent sales growth of firms and its relation depends on the firms' characteristics. Conclusion: We suggest the emphasis on R&D investment for firms' growth and the differentiated R&D program based on firm size. This article has the limitation that various types of R&D investment cannot be included in this analysis.

• 대한기계학회논문집A
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• 제29권3호
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• pp.484-494
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• 2005

Finite element method is very effective method to simulate the forming processes with good prediction of the deformation behaviour. For the finite element modeling of sheet mental forming the accurate tool model is required. Due to the geometrical complexity of real-size part stamping tools it is hard to make FE model for real-size auto-body stamping parts. In this paper, it was focussed on the drawability factors on auto-body panel stamping by AUTOFORM with using tool planing alloy to reduce law price as well as high precision from Design Optimization of die. According to this study, the results of simulation will give engineers good information to access the Design Optimization of die.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 추계학술대회논문집
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• pp.138-141
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• 2004

Finite element method is very effective method to simulate the forming processes with good prediction of the deformation behaviour. For the finite element modeling of sheet mental forming the accurate tool model is required. Due to the geometrical complexity of real-size part stamping tools it is hard to make FE model for real-size auto-body stamping parts. In this paper, it was focussed on the drawability factors on auto-body panel stamping by AUTOFORM with using tool planing alloy to reduce law price as well as high precision from Design Optimization of die. According to this study, the results of simulation will give engineers good information to access the Design Optimization of die.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.416-421
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• 2010

The north and south panel of a geostationary satellite are used for radiator panels to reject internal heat dissipation of electronics units and utilize several heat pipe networks to control the temperatures of units and the satellite within proper ranges. The design of these panels is very important and essential at the conceptual design and preliminary design stage so several thousands of nodes of more are utilized in order to perform thermal analysis of panel. Generating a large number of nodes(meshes) of the panel takes time and is tedious work because the mesh can be easily changed and updated by locations of units and heat pipes. Also the detailed panel model can not be integrated into spacecraft thermal model due to its node size and limitation of commercial satellite thermal analysis program. Thus development of a program was required in order to generate detailed panel model, to perform thermal analysis and to make a reduced panel model for the integration to the satellite thermal model. This paper describes the development and the verification of panel thermal analysis program with ist main modules and its main functions.

• 한국전산유체공학회지
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• 제15권3호
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• pp.66-72
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• 2010

The north and south panel of a geostationary satellite are used for radiator panels to reject internal heat and utilize several heat pipe networks to control the temperatures of units and the main structures of satellite within proper ranges. The design of these panels is very important and essential at the conceptual design and preliminary satellite design stage, so several thousands of nodes or more are utilized in order to perform detailed thermal analysis of panel. Generating a large number of panel nodes takes time and is tedious work because the nodes can be easily changed and updated by locations of units and heat pipes. Also the detailed panel model can not be integrated into spacecraft thermal model due to its node size and limitation of commercial satellite thermal analysis program. Thus development of a program was required to generate a detailed panel model, to perform thermal analysis and to make a reduced panel model for the integration to the satellite thermal model. This paper describes the development and the verification of the panel thermal analysis program with its main modules and functions.

• 한국멀티미디어학회논문지
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• 제15권4호
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• pp.439-448
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• 2012

TFT-LCD 패널을 저해상도로 획득한 영상은 불균일한 휘도 분포와 노이즈 신호, 그리고 결함 신호로 구성되어 있다. 불균일한 휘도 분포와 노이즈로 인해 결함 신호를 분할하기 어려우며 이를 위해 다양한 분할 방법이 개발되고 있다. 본 논문에서는 공간영역 상에서 Eikvil et al.'s에 의해 제안되어진 크기가 다른 두 개의 창을 두고 각 창의 평균을 계산하고 그 값의 차이를 이용하는 방법을 이용하여 TFT-LCD 패널 이미지 상에 존재하는 결함의 영역을 분할하는 방법을 제안한다. 하지만 이 방법은 창의 크기에 의해 검출 가능한 결함영역의 크기가 제한되어 큰 결함영역을 분할하기 위해서는 창을 키워야 하므로 효율적이지 못한 문제점을 가지고 있다. 이 문제를 해결하기위해 멀티스케일(Multi-scale)을 이용하고, 각 스케일에서 검출 가능한 결함 크기를 제한함으로써 다양한 크기의 결함 영역을 분할 할 수 있는 알고리즘을 제안한다. 알고리즘의 성능을 검증하기위해 다양한 크기의 결함 영역을 만들어 분할되어진 결과와 실제 결함이 존재하는 TFT-LCD 패널 이미지의 분할 결과들을 통해 실제 적용 가능한 알고리즘임을 보인다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 추계 학술논문 발표대회
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• pp.204-205
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• 2015

Demands for free-form buildings are on the rise, but such building designs require most cost and longer construction schedule, with less constructability due to challenges in construction member production and installation. FCP production technology has been developed using CNC machine in a bid to resolve the difficulties of member production. Exterior finishing panels of free-form building design must be divided in size and shape that can be produced by CNC machine. To solve this problem, constraints of CNC machine and correlations between CNC machine and panel need to be reviewed. Thus, the purpose of this study is to analyze decision factors on free-form concrete panel sizes produced by CNC machines. Through this study, FCP size can be optimized, which in turn can lead to improved FCP productivity and aesthetical quality of free-form building designs determined by the pattern of exterior finishing panels. CNC machine-enabled free-form concrete panel production technology will apply on site in the future, which will not only maximize the economic benefits of the technology but also support shorter construction schedule and better constructability.

• Journal of Welding and Joining
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• 제25권1호
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• pp.49-56
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• 2007

Prediction and control of the thermal distortion is particularly important for the design and manufacture of welded thin plate panel. In this study, experiments and computations are performed to analyze effect of a hole configuration and a specimen size on distortion. In addition, this study aims to develop a thermal elasto-plastic simulation using finite element method to predict distortion, with particular emphasis on buckling deformation generated in plates welded around hole. From the experiments, the severe distortion appeared in the weldments by the laser welding process, in which the specimen size plays an important role on the distortion but the hole configuration showed little effect. And the results of numerical analysis were corresponded well with the experiment ones. Thus, a thermal elasto-plastic analysis model for predicting the weld distortion of thin plate panel was successfully developed through this study.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2006년도 전력전자학술대회 논문집
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• pp.403-405
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• 2006

Over the years, plasma display panel (PDP) manufacturers have impressed the flat panel display industry with yet another new product essentially having the merits of a larger screen size. Since larger size implies higher power ratings, voltage/current ratings of the power devices used have become a rising concern. Another important concern is the brightness of PDP, one way of increasing which is by operating the PDP at higher frequencies. In order to address the above issues, a transformer coupled sustain-driver for AC-PDP is proposed During the transition time, the two windings of the transformer greatly boost up the displacement current flowing through the panel capacitance and hence enable a fast inversion of the voltage polarity with practical values of resonant inductance. In the proposed topology, the resonant inductance can be increased by a factor of $(n+1)^2$ as compared to prior approaches. Increased inductance results in lower current stresses. Moreover, high frequency operation is possible by using higher value of n (turn ratio of the transformer). The operational principle and design procedure of the proposed circuit are presented with theoretical analysis. The validity of the proposed sustain driver is established through simulation and experimental results using a 42-in PDP

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.725-730
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• 2008

In this study, we found out charged particle's deposition characteristic by experiments of $0.5{\mu}m$, $1.0{\mu}m$, $3.0{\mu}m$ size particle's concentration decay. We carried out the experiments on charged particle deposition onto the vertical cleanroom wall panel and some other fundamental experiments. The particle deposition mechanism is consist of sedimentation, convection, diffusion, thermophoresis, electrostatic and so on. Particle size determines mainly working deposition mechanism. The charged particle is made with corona discharge that are constituted field charging and diffusion charging. In addition, this combinational mechanism is called combined charging. The type of corona discharge determines quantity of particle electrical charge. In conclusion, we assumed that quantity of particle electrical charge accelerations deposition velocity onto the vertical cleanroom wall panel and proved it. And we figured out particle's deposition characteristic through compared between our experiment's results.