• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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• pp.344-347
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• 2008

Ocean surface waves may be modified by ocean current and their observation may be severely distorted if the observer is on a moving platform with changing speed. Tidal current near a sill varies inversely with the water depth, and results spatially inhomogeneous modulation on the surface waves near the sill. For waves propagating upstream, they will encounter stronger current before reaching the sill, and therefore, they will shorten their wavelength with frequency unchanged, increase its amplitude, and it may break if the wave height is larger than 1/7 of the wavelength. These small scale (${\sim}$ 1 km changes is not suitable for satellite radar observation. Spatial distribution of wave-height spectra S(x, y) can not be acquired from wave gauges that are designed for collecting 2-D wave spectra at fixed locations, nor from satellite radar image which is more suitable for observing long swells. Optical images collected from cameras on-board a ship, over high-ground, or onboard an unmanned auto-piloting vehicle (UAV) may have pixel size that is small enough to resolve decimeter-scale short gravity waves. If diffuse sky light is the only source of lighting and it is uniform in camera-viewing directions, then the image intensity is proportional to the surface reflectance R(x, y) of diffuse light, and R is directly related to the surface slope. The slope spectrum and wave-height spectra S(x, y) may then be derived from R(x, y). The results are compared with the in situ measurement of wave spectra over Keelung Sill from a research vessel. The application of this method is for analysis and interpretation of satellite images on studies of current and wave interaction that often require fine scale information of wave-height spectra S(x, y) that changes dynamically with time and space.

• Archives of Plastic Surgery
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• 제36권5호
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• pp.637-641
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• 2009

Purpose: Most unilateral secondary cleft lip nose deformities have depressed nostril base and sill on the cleft side. To obtain a symmetric nose, correction of the recession on nostril is critical. The authors have worked out effective methods to elevate the nostril of the cleft side according to the extent of the depression. Methods: A total of 115 unilateral secondary cleft lip nose deformity patients with nostril depression were evaluated. Data were acquired from patients' charts and photography with special reference to the height difference of the nostrils between the cleft side and the non - cleft side. Patients were divided into three groups based on the difference and operated with various techniques : (1) mild degree(< 1 mm) with graft, (2) moderate degree(1 ~ 3 mm) with C - flap or suspension suture of septal cartilage (3) severe degree(> 3 mm) with graft, C - flap and suspension suture. Follow - up period averaged 21.3 months. Results: Forty - six patients(40 percent) were in mild group, and forty - two(37 percent) were in moderate. In twenty - seven patients(23 percent), nostril recession was more than 3 mm. The elevated nostril base and sill were maintained without height alteration during follow - up. Conclusion: The symmetry of the nostril base, especially projection of nostril sill influences successful correction of unilateral cleft lip nose deformity. Our tolerable techniques can be applied to most deformities with nostril depression and can present a new guideline.

• 소성∙가공
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• 제23권6호
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• pp.376-379
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• 2014

During roll forming a sheet metal is continuously and progressively formed into a product of the required cross-section and longitudinal shape. An example product is a circular tube with a required diameter, wall-thickness and straightness. Roll forming occurs by passing the sheet through a series of forming rolls that are arranged in tandem. Each pair of forming rolls in the roll forming line plays a particular role in obtaining the required cross-section and longitudinal shape in the product. In recent years, that process is often applied to car body parts by automotive industries. In the current study, an optimal model design and proper roll-pass sequences as well as the number of forming rolls and bending angles were used to produce a sill side. The effects of the process parameters on the final shape formed by roll forming defects were evaluated.

• East Asian mathematical journal
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• 제13권1호
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• pp.1-10
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• 1997

• 한국전자거래학회:학술대회논문집
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• 한국전자거래학회 2005년도 e-Biz World Conference 2005
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• pp.108-113
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• 2005

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2003년도 학술발표회논문집(2)
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• pp.779-782
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• 2003

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.931-938
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• 2011

Nondestructive inspection(NDI) is a testing procedure used to easily inspect an object for internal defects, abnormalities, shape, and structure, etc. without destroying it. Typical candidates for NDI include buildings, railways, aircraft, bridges, underground pipelines and various types of factory equipment. Recent advances in nondestructive evaluation(NDE) technologies have led to improved methods for quality control and in-service inspection, and the development of new options for material diagnostics. Under frame side sill in rolling stocks is designed for preventing corrosion in order to meet mechanical requirements. However during long operation time, there are corrosion in the under frame side sill caused by environmental effect, vibration and etc. This paper introduces the methods of a survey and assessment on NDI applications in Electric Multiple Units(EMU). The main objective of this paper was to obtain information on various applications and evaluation of NDI technology in EMU.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1410-1413
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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 planning 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.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.82-85
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• 2003

강원도 춘천시 신북읍 유포리 연구지역의 지하수의 NO$_3$-N 2차원 공간 분포를 정의하기 위하여 지구통계학적 해석 방법인 sequential Gaussian simulation(SGS)을 이용하였다. 원자료의 공간적 clustering을 제거하기 위하여 cell declustering을 수행한 후 normal score 변환을 거친 후 variogram 분석과 모델링을 수행하였다. Exponential, gaussian, spherical variogram model에 대한 각각의 nugget, range, sill을 정의하여 SGS에 이용하였다. SGS에 의해 도출된 결과들은 모두 동일한 결과를 나타낸다. 또한 관측 자료의 분포와 주 오염원의 분포와 상응하는 모델링 결과를 나타내는 것으로 보아 SGS를 이용한 농촌지역 지하수내 NO$_3$-N의 공간적 오염 분포 영상화가 매우 유용하게 활용될 수 있을 것으로 판단된다.