• 대한화학회지
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• 제42권5호
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• pp.506-511
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• 1998

생체 내에서 양이온을 가지는 폴리아민류인 스퍼민이 DNA에 결합할 경우 안정화도를 증가시킴과 동시에 구조적인 변환(B형태→Z형태 변환)을 유발하는 것으로 알려져 있다. 그러나, 스퍼민의 분광학적 비활성 때문에 DNA에 대한 정확한 결합 위치를 분광학적으로 결정하는 것은 불가능했으므로 그 결합메커니즘에 관한 구체적인 보고는 없다. 본 실험에서는 스퍼민에 대한 탐침 작용을 할 수 있는 물질로 분광 활성이 있으며 결합 자리를 잘 알고 있는 DAPI를 사용하였다. 합성 DNA에서 스퍼민의 결합 자리와 염기 선택성을 연구한 결과, 스퍼민의 농도가 커질수록 아데닌-티민 염기쌍이 교대로 나선을 이루는 $poly[d(A-T)_{2}]$ 에서는 스퍼민이 DNA의 작은 홈 주위의 인산기 뼈대에 걸쳐지면 DAPI의 소수성 환경을 증가시켜 형광스펙트럼의 세기를 급격히 증가시킨다. 구아닌-시토신 염기쌍이 교대로 반복되며 만들어진 $poly[d(G-C)_{2}]$에서는 스퍼민이 DNA의 큰 홈 속에 결합하면서 큰 홈에 걸쳐 있으면서 부분적으로 염기쌍사이에 삽입된 DAPI를 밀어내는 것으로 생각할 수 있다. 이 두 가지의 경우에 스퍼민이 염기쌍에 대해 특별한 선택성을 보이지 않았다.

• 대한전자공학회논문지SP
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• 제48권6호
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• pp.115-123
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• 2011

일반적으로 실제 사용되는 카메라들은 렌즈 왜곡이 존재하며, 렌즈왜곡의 정도는 카메라의 가격뿐만 아니라 특정 용도에 의해 달라진다. 현재까지의 많은 렌즈 왜곡 보정기법들은 왜곡 변수를 찾기 위해 투영 기하학의 불변량 속성을 기반으로 한 것으로, "물체의 직선은 이미지에서의 직선"이라는 상식에서 출발한다. 하지만, 평행선인 경우 이전의 연구들은 렌즈 왜곡 변수를 결정하는데 제약이 있다. 본 논문에서는 렌즈왜곡 변수를 결정할 때 동시에 평행선 유지를 보증할 수 있는 방법을 제안함으로써, 핀홀 카메라 모델을 이용하여 투영된 이미지와 실제 이미지가 근접한 결과를 얻게 된다. 실제 이미지와 제안된 기법을 사용한 보정이미지를 비교하여 그 효율성을 입증하였다.

• 한국응용과학기술학회지
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• 제15권3호
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• pp.61-66
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• 1998

Cyclodextrin are obtained from starch by enzymatic degradation. The three best characterize forms are ${\alpha}$, ${\beta}$, ${\gamma}$ cyclodextrin consisting of 6, 7, and 8 D-glucose units, respectively. Each of the glucose units are in the rigid C1 chair conformation and are linked by ${\alpha}$ 1,4 bonds. This geometry gives the cyclodextrin the shape of a hollow truncated cone with the wider side formed by the secondary 2- and 3-hydroxy groups and the narrower side by the primary 6-hydroxy group. The most characteristics property of the cyclodextrin is their ability to form inclusion complexes with a wide range of guest moleculars. We syntheses per-6-substituted ${\beta}$-cyclodextrin derivatives and investigate structures, spectrospcopic properties. The substituted materials are piperidine, piperazin, morphorine. The synthetic compound showed a good solubility than natural ${\beta}$ cyclodextrin in organic solvents such as methylene chloride, methanol, ethanol, etc.

• 대한전자공학회논문지SP
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• 제39권1호
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• pp.40-48
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• 2002

시점을 달리하는 영상으로부터 3차원 장면 복구는 두 영상의 에피폴라 기하구조를 나타내는 F-행렬을 계산함으로서 가능하다. F-행렬을 계산하기 위해 입력으로 주어지는 두 영상의 일치점에는 잘못된 정합점과 같은 잡음을 포함하고 있기 때문에 정확한 F-행렬의 계산은 많은 오류를 가지게 된다. 따라서 본 논문에서는 에피폴라 기하구조에 영향을 미치는 잡음의 종류를 크게 outlier와 미세잡음으로 구분하였다. 상대적으로 에피폴라 기하구조에 영향을 크게 미치는 outlier를 단계적으로 제거시킴으로써 잡음 환경에서도 효과적으로 F-행렬을 계산할 수 있는 SSOR 알고리즘을 제안한다. 제안 알고리즘의 성능 평가를 위해 합성영상과 실 영상에서 실험하였으며 실험결과 제안 알고리즘이 기존의 알고리즘보다 성능이 우수함을 확인하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.625-628
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• 2007

We present an efficient and robust technique to estimate the velocity of moving targets from a single SAR image. In SAR images, azimuth image shift is a well known phenomenon, which is observed in moving targets having slant-range velocity. Most methods estimated the velocity of moving targets from the distance difference between the road and moving targets or between ship and the ship wake. However, the methods could not be always applied to moving targets because it is difficult to find the road and the ship wake. We adopted a method estimating the velocity of moving targets from azimuth differentials of range-compressed image. This method is based on an assumption that Doppler center frequency shift of moving target causes a phase difference in azimuth differential values. The phase difference is linearly distorted by Doppler rate due to the geometry of SAR image. The linear distortion is eliminated from phase removal procedure, and the constant phase difference is estimated. Finally, range velocity estimates for moving targets are retrieved. This technique is tested using an ENVISAT ASAR image in which several unknown ships are presented. The theoretical accuracy of this technique is discussed by SAR simulation. The advantages and disadvantages of this method over the conventional method are also discussed.

• 자원환경지질
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• 제28권5호
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• pp.481-485
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• 1995

본 논문에서는 탄성파 굴절법 탐사자료를 이용하여 천부지층의 속도와 심도를 결정하기 위한 새로운 접근방법을 소개한다. 굴절법 자료로부터 초동을 발췌한 후 실제 합성단면도를 이러한 초동의 시간이동에 해당하는 단위 델타 함수로 대치할 수 있다고 가정하였다. 주시의 계산은 발사법 파선추척을 이용하였다. 감쇠 최소자승법의 적용을 위한 편미분치의 계산은 이론주시의 계산과 동시에 해석적으로 구하였다. 본 역산법은 합성자료와 현장자료에 적용하여 성공적인 결과를 가져왔으며, 초기 가정 모델이 실제 모델과 많이 다르더라도 저주파수 대역에서 매우 양호한 결과를 보여주는 장점을 지닌다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.225-227
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• 2003

Traditional photogrammetry and satellite image rectification technique have been developed based on control-points for many decades. These techniques are driven from linked points in image space and the corresponding points in the object space in rigorous colinearity or coplanarity conditions. Recently, digital imagery facilitates the opportunity to use features as well as points for images rectification. These implementations were mainly based on rigorous models that incorporated geometric constraints into the bundle adjustment and could not be applied to the new high-resolution satellite imagery (HRSI) due to the absence of sensor calibration and satellite orbit information. This research is an attempt to establish a new Line Based Transformation Model (LBTM), which is based on linear features only or linear features with a number of ground control points instead of the traditional models that only use Ground Control Points (GCPs) for satellite imagery rectification. The new model does not require any further information about the sensor model or satellite ephemeris data. Synthetic as well as real data have been demonestrated to check the validity and fidelity of the new approach and the results showed that the LBTM can be used efficiently for rectifying HRSI.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2014년도 춘계학술발표대회
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• pp.904-907
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• 2014

In this work we present a robust and fast approach to estimate 3D vehicle pose that can provide results under a specific traffic surveillance conditions. Such limitations are expressed by single fixed CCTV camera that is located relatively high above the ground, its pitch axes is parallel to the reference plane and the camera focus assumed to be known. The benefit of our framework that it does not require prior training, camera calibration and does not heavily rely on 3D model shape as most common technics do. Also it deals with a bad shape condition of the objects as we focused on low resolution surveillance scenes. Pose estimation task is presented as PnP problem to solve it we use well known "POSIT" algorithm [1]. In order to use this algorithm at least 4 non coplanar point's correspondence is required. To find such we propose a set of techniques based on model and scene geometry. Our framework can be applied in real time video sequence. Results for estimated vehicle pose are shown in real image scene.

• 대한원격탐사학회지
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• 제35권1호
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• pp.15-28
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• 2019

By applying the method of SAR interferometry to X-band synthetic aperture radar (SAR) image of COSMO-SkyMed, detailed motion patterns of five glaciers in the Parlung Zangbo River basin, Tibetan Plateau, in January 2010 have been derived. The results indicate that flow patterns are generally constrained by the valley geometry and terrain complexity. The maximum of $123.9ma^{-1}$ is observed on glacier No.1 and the minimum of $39.4ma^{-1}$ is found on glacier No.3. The mean values of five glaciers are between 22.9 and $98.2ma^{-1}$. Glaciers No.1, No.2, No.4 and No.5 exhibit high velocities in their upper sections with big slope and low velocities in the lower sections. A moraine lake accelerates the speed of mass exchange leading to a fast flow at the terminal of glacier No.3. These glaciers generally move along the direction of decreased elevation and present a macroscopic illustration of the motion from the northwest to the southeast. The accuracy of DEM and registration conditions of DEM-simulated terrain phases has certain effects on calculations of glacier flow direction and velocity. The error field is relatively fragmented in areas inconsistent with the main flow line of the glaciers, and the shape and uniformity of glacier are directly related to the continuous distribution of flow velocity errors.

• 한국지하수토양환경학회지:지하수토양환경
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• 제25권4호
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• pp.87-97
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• 2020

In this study, the applicability of the geostatistical evolution strategy as an inverse analysis method of estimating hydraulic properties of small-scale basin was tested. The geostatistical evolution strategy is a type of data assimilation method that can effectively estimate aquifer hydraulic conductivity by combining a global optimization model of the evolution strategy and a local optimization model of the ensemble Kalman filtering. In the applicability test, the geometry, hydraulic boundary conditions, and the distribution of groundwater monitoring wells of Hanlim-Eup were employed. On the other hand, a synthetic hydraulic conductivity distribution was generated and used as the reference property for ease of estimation quality assessment. In the estimations, two different cases were tested where, in Case I, both groundwater levels and hydraulic conductivity measurements were assumed to be available, and only the groundwater levels were available, in Case II. In both cases, the reference and estimated hydraulic conductivity fields were found to show reasonable similarity, even though the prior information for estimation was not accurate. The ability to estimate hydraulic conductivity without accurate prior information suggests that this method can be used effectively to estimate mathematical properties in real-world cases, many of which little prior information is available for the aquifer conditions.