• 한국컴퓨터그래픽스학회논문지
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• 제3권1호
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• pp.9-15
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• 1997

지금까지 대부분의 렌더링(rendering)에 대한 연구는 빛의 반사(reflection)와 광원과 물체 표면에서의 조명(illumination)에 대한 것이었다. Kolb가 [1]에서 밝힌 것처럼 카메라와 렌즈에 대한 연구는 렌더링 연구에서 중요한 요소임에도 불구하고 연구 결과가 많지 않았다. 본 논문에서는 카메라 렌즈에서의 범프 맵핑과 새로운 렌즈개발을 위한 프레임 워크를 소개한다. 이 프레임 워크는 새로운 렌즈 개발에 쓰일 수 있고, 범프 맵핑은 그림 2,3,4,5에서처럼 어안 렌즈등 여러 다른 렌즈들과 혼합되어 다양한 효과를 거둘 수 있다.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2004년도 추계학술발표회 논문집
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• pp.263-268
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• 2004

GPS/INS에 의한 항공사진측량을 이용하려면 사진촬영과 동시에 획득한 외부표정요소의 결과를 도화ㆍ편집 작업에 실제로 적용해 보아야 한다. 도화성과의 검증작업은 GPS/INS의 결과를 이용하여 수치지도의 제작시 가장 중요한 공정에 해당한다. 이를 위하여 기존 AT성과에 의하여 제작된 해석도화원도를 기준으로 본 연구에서 제시한 AT 성과별, 도화기별, 표정방식별로 수행한 도화결과를 비교하였다. AT 성과와 표정방법에 상관없이 해석도화와 수치도화의 평면과 표고의 오차를 비교하여 보면, 해석도화가 수치도화보다 우수한 결과를 보여주며, 또한 평면오차가 표고오차보다 더 크게 나타남을 알 수 있었다. GPS/INS AT의 Direct 표정의 경우 InDirect 표정방법에 비해 3배 이상의 오차가 발생하였으나 모든 경우의 결과가 허용오차를 충족하고 있으므로 축척 1:5000에서는 GPS/INS AT를 이용한 표정과 도화작업은 매우 효율적으로 수행될 수 있음을 알 수 있었다.

• 응용통계연구
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• 제17권3호
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• pp.431-443
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• 2004

본 연구에서는 질병지도작성(disease mapping)을 위해 인접지역의 정보를 효과적으로 활용할 수 있는 EB(empirical Bayes) 추정 법과 HGLM(hierarchial generalized linear model)을 기초로 한 추정법을 다룬다. 사례연구로 이 추정방법들을 이용하여 2000년 사망원인통계자료를 이용해 경상도 및 전라도의 112개 시$.$군$.$구 단위 행정자치구역별 45세 이상 폐암 사망률을 산출하고, 경상도 및 전라도 지역 폐암 사망률 지도를 작성한다. 아울러 제시된 방법들에 위해 얻어진 추정치들의 변동과 3년간 평균 사망률을 기준으로 구한 MSD(mean square deviation)를 이용하여 추정방법들의 특성을 비교 분석한다.

• 한국전산응용수학회:학술대회논문집
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• 한국전산응용수학회 2003년도 KSCAM 학술발표회 프로그램 및 초록집
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• pp.17.2-17
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• 2003

The purpose of this paper is to solve the generalized Hyers-Ulam stability problem for a cubic functional equation 8f(x-y/2)＋8f(y-x/2)＋2f(x＋y)=9f(x)＋9f(y) on the basis of a direct method.

• East Asian mathematical journal
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• 제35권3호
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• pp.331-340
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• 2019

In this paper, we investigate the stability for the functional equation $f(x+ky)-kf(x+y)+kf(x-y)-f(x-ky)-(k^3-k)f(y)+(k^3-k)f(-y)=0$ in the sense of M. S. Moslehian and Th. M. Rassias.

• Korean Journal of Radiology
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• 제24권6호
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• pp.553-563
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• 2023

Objective: Functional magnetic resonance imaging (fMRI) and diffusion tensor imaging-derived tractography (DTI-t) contribute to the localization of language areas, but their accuracy remains controversial. This study aimed to investigate the diagnostic performance of preoperative fMRI and DTI-t obtained with a simultaneous multi-slice technique using intraoperative direct cortical stimulation (DCS) or corticocortical evoked potential (CCEP) as reference standards. Materials and Methods: This prospective study included 26 patients (23-74 years; male:female, 13:13) with tumors in the vicinity of Broca's area who underwent preoperative fMRI and DTI-t. A site-by-site comparison between preoperative (fMRI and DTI-t) and intraoperative language mapping (DCS or CCEP) was performed for 226 cortical sites to calculate the sensitivity and specificity of fMRI and DTI-t for mapping Broca's areas. For sites with positive signals on fMRI or DTI-t, the true-positive rate (TPR) was calculated based on the concordance and discordance between fMRI and DTI-t. Results: Among 226 cortical sites, DCS was performed in 100 sites and CCEP was performed in 166 sites. The specificities of fMRI and DTI-t ranged from 72.4% (63/87) to 96.8% (122/126), respectively. The sensitivities of fMRI (except for verb generation) and DTI-t were 69.2% (9/13) to 92.3% (12/13) with DCS as the reference standard, and 40.0% (16/40) or lower with CCEP as the reference standard. For sites with preoperative fMRI or DTI-t positivity (n = 82), the TPR was high when fMRI and DTI-t were concordant (81.2% and 100% using DCS and CCEP, respectively, as the reference standards) and low when fMRI and DTI-t were discordant (≤ 24.2%). Conclusion: fMRI and DTI-t are sensitive and specific for mapping Broca's area compared with DCS and specific but insensitive compared with CCEP. A site with a positive signal on both fMRI and DTI-t represents a high probability of being an essential language area.

• 한국산업융합학회 논문집
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• 제23권6_2호
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• pp.1043-1050
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• 2020

In this study, a study was presented on the monitoring technique of landslide area using UAV. In the case of disaster investigation using drone mapping, it can be used at various disaster sites. The mission can be carried out at various disaster sites, including surveys of damage to mountainous areas caused by landslides, building collapses surveys of flood damage, typhoons, earthquakes. The damage investigation plan using drone mapping is expected to be highly utilized at disaster sites where investigators cannot access it like in mountainous areas and where it is difficult to conduct direct damage investigations at the site. Drone mapping technology has many advantages in terms of disaster follow-up, such as recovery. Compared to the existing survey system, which was mainly carried out manually, the investigation time can be drastically reduced, and it can also respond to disaster sites that are difficult to carry out or are difficult to access directly. In addition, it is possible to establish and guide spatial data at the disaster site based on accurate mapping data from the time of the disaster, which has considerable strength in managing the situation of the disaster site, selecting priority areas for recovery, and establishing recovery plans. As such, drone mapping is a technology that can be used in a wide range of sites along with natural disasters and social disasters. If a damage investigation system is established through this, it is believed that it will contribute significantly to the rapid establishment of recovery plans along with the investigation of disaster response time and extent of damage recovery.

• 한국정밀공학회지
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• 제21권4호
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• pp.88-94
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• 2004

Recently, vehicle simulators are widely used to evaluate driver's responses and driver assistance systems. It needs much effort to construct the virtual driving environment for a vehicle simulator. In this study, it is described how to make effectively the roads and the driving environment for a vehicle simulator. The GIS (Geographic Information System) is used to construct the roads and the environment effectively. Because the GIS is the integrated system of geographical data, it contains useful data to make virtual driving environment. First, the outline and centerline of roads is abstracted from the GIS. From the road outline, the road width is calculated. Using the centerline, the grid model of roads is constructed. The final graphic model of roads is constructed by mapping road image to the grid model according to the number of lanes and the kind of surface. Data of buildings from the GIS are abstracted. Each shape and height of buildings is determined according to kind of buildings, the final graphic model of buildings is constructed. Then, the graphic model of roadside tree is also constructed. Finally, the driving environment for driving simulator is constructed by converting the three graphic models with the graphic format of Direct-X and by joining the three graphic models.

• 항공우주산업기술동향
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• 제6권2호
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• pp.80-89
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• 2008

사진측정기는 2차원 사진 이미지를 사용해 비접촉식으로 3차원 좌표를 측정한다. 사진측정기는 2차원 사진으로부터 3차원 데이터를 재구성하기 위해 삼각측량법을 사용한다. 디지털 사진측정기는 측정사진에 대한 맵핑(mapping)과 비율 조정(scaling) 그리고 번들(bundle) 조정이 소프트웨어로 동시에 계산되며 이를 통해 카메라의 위치와 좌표를 해석해 낸다. 본 연구에서는 대형전파망원경의 구조적인 변형 측정, ISIM 시험 구조체의 사진측정기 결과 분석, 원자로 연료 조립물에 대한 수중 사진측정, 위성 광학 조립부 측정 및 위성 지상지원장비 측정과 같은 특별한 용도로 사용된 사진 측정기에 대해 소개하였다.

• 한국자동차공학회논문집
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• 제13권4호
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• pp.167-173
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• 2005

Thermal regeneration means burning-off and cleaning-up the particulate matters piled up in DPF(diesel particulate filter), and it requires both high temperature $(550\~600^{\circ}C)$ and appropriate concentration of oxygen at DPF entrance. However, it is not easy to satisfy such conditions because of the low temperature window of the HSDI(high speed direct injection) diesel engine(approximately $200\~350^{\circ}C$ at cycle). Therefore, this study is focused on the method to raise temperature using the trade-off relation between temperature, oxygen concentration, and the influence of many parameters of common rail injection system including post injection. After performing an optimal mapping of the common rail parameters for regeneration mode, the actual cleaning process during regeneration mode is investigated and evaluated the availability of the regeneration mode mapping through regenerating soot trapped in the DPF.