• Journal of Korean Ophthalmic Optics Society
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• v.13 no.4
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• pp.65-73
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• 2008

Purpose: The purpose of this study is to investigate the effect of age in the response to long-term overnight orthokeratology (OK) lens wearing. Methods: Among volunteers, ninety-five healthy subjects who had no eye diseases and could wear OK contact lens at least for 8 hours every day were divided into three groups children, youngsters and young adults. Unaided logMAR visual acuity, refractive error, apical corneal radius, corneal asphericity and central corneal thickness were measured with different period; before and after one day, one week, two weeks, one month, three months and six months of OK lens wear. Paired student t-test, ANOVA analysis and Pearson correlation were used with a critical p value of 0.05 for statistical analysis. Results: All groups showed statistically significant (p<0.001) improvement in unaided visual acuity, a trend for flattening in the apical corneal radius, decrease in central corneal thickness and less prolate after OK lens wear. The child group showed significantly rapid change (p<0.001) in visual acuity, and apical corneal radius showed that they reached the targeted refractive change earlier compared with youngster and adult groups. The visual effect of OK lens was significantly related with the change in central corneal thickness after long-term OK lens wear, especially in child and youngster group, and central corneal thickness were highly correlated with the targeted refractive change. Conclusions: Visual acuity change is statistically correlated with the central corneal thickness change, which is highly correlated with targeted refractive change in the long-term orthokeratology and younger lens wearers showed a rapid response to OK lens wear, suggesting a reduced epithelial response with increasing age. The results found this study extends our understanding and development in the long-term orthokeratology.

• Electronics and Telecommunications Trends
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• v.12 no.2 s.44
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• pp.79-102
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• 1997

본 고에서는 국내 시각 및 청각 장애인을 위한 복지통신 서비스 및 기기개발과 정부의 복지통신 정책수립에 필요한 기초자료를 마련하기 위해, 실제 장애인을 대상으로 정보통신 서비스와 기기에 대한 사용현황 및 수요를 정성조사와 정량조사 방법을 이용하여 조사/분석하였으며, 이를 바탕으로 정부의 복지통신정책 수립과 기기개발에 반영되어야 할 몇가지 의견을 제시하였다.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.36-39
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• 1997

In this paper, we described an approach to design of precision optical system for visual inspection of solder joint defects of SMC(surface mount components) on PCBs(Printed Circuit Board). The illumination system, consisting of three tiered LED lamps and one main camera and four side view camera, is implemented to generated iso-contour on the solder joint according to gradient of the soldered surface. We analyze LED design parameter such as incident angle, diameter of LED ring, and so on to acquire uniform illumination.

• Journal of the Korean Chemical Society
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• v.58 no.5
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• pp.490-495
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• 2014

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2008.04a
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• pp.442-445
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• 2008

The purpose of this study is making Proto-type development of BIM based Architectural Construction Simulation System. This study suggest a new schedule access method for overcoming limitation of current Simulation Program focused on visualization. The method made from analysis of current Simulation Program. This program is based on Visual Basic .Net language.

• Proceedings of the Acoustical Society of Korea Conference
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• 1998.06c
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• pp.167-170
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• 1998

음성신호의 특징적인 성분인 피치를 검출하는 알고리즘 중 실시산 구현이 손쉬운 3단계를 클리핑 알고리즘을 PC상에서의 처리를 위하여 구현하였다. 이 알고리즘을 통하여 검출되는 피치의 안정성 및 정확성을 높이기 위해서 적용된 창함수, LPF, 클리핑 자기상관값계산, 비선형 감쇄, 등의 전처리 필터링과, 배수피치 검출 및 정정, 메디언 필터링을 사용하여 피치를 검출하였다. 또한 이 알고리즘을 이용하여 DSP의 도움을 얻지 않고 PC상에서 음성을 분석하여 스펙트로그램, 파형, 에너지, 피치 등을 출력하는 프로그램인 Visual Analysis Tool for sounds(VAT)의 출력화면을 통하여 피치검출을 나타내었다.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.2
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• pp.131-139
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• 2003

Shape descriptors play an important role in systems for object recognition, retrieval, registration, and analysis. Seven well-known descriptors including MPEG-7 visual descriptors arebriefly reviewed and a new robust pattern recognition descriptor is proposed. Performance comparison among descriptors are presented. Experiments show that the newly proposed descriptor yields better performance results than Fourier, invariant moment, and edge histogram descriptors.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2003.04a
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• pp.146-151
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• 2003

작물의 생장상태를 측정하고자 기존의 연구자들에 의해서 많은 연구가 수행되고 있다(Hatou 등, 1995, Shimizu와 Hems, 1995; 김 등, 1998; 성, 1995). 그러나 작물의 생장을 감시하기 위한 기존의 방법은 파괴적이며 지속적이지 못한 단점을 지니고 있다. 작물이 스트레스를 받아 눈에 띄게 작물의 생장변화가 보일 경우 작물은 이미 영구적인 손상을 받게 된다. (중략)

• Proceedings of the Korea Multimedia Society Conference
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• 2003.11b
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• pp.613-620
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• 2003

애니메이션의 사전제작과정에서 캐릭터의 보다 효율적 제작, 분석, 평가을 위해 시각적 모델화및 데이터 베이스 구축이 필요했다. 캐릭터의 체격과 기질 관계를 조명하기 위해 W. 셀던의 체격기질유형 이론으로부터 정형화된 분석 틀을 구축하여 개념을 시각화하고 유형분석 모델을 만들었으며, 또한 케이스 스터디를 위해 세 애니메이션에 나타난 캐릭터의 유형들을 분석함으로써 모델의 적용 가능성과 나아가 애니메이션의 캐릭터에서 표현된 외적 형상과 내적 기질의 상관성을 추론하여 실제 적용이 가능한 기초적 데이터가 되도록 하였다.

• Journal of Ocean Engineering and Technology
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• v.14 no.3
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• pp.35-40
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• 2000

SMAC method is, one of the numerical simulation techniques, modified from the original MAC for the time-dependent variation of fluid flows. The Navier-Stokes equation for incompressible time-dependent viscous flow is applied and, also marker particles which move with the fluid are used. Two-dimensional numerical computations of fluid flow are carried out in a virtual water tank. This paper has shown very well the movements of marker particles using SMAC method.