• 한국정보통신학회논문지
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• 제25권6호
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• pp.799-806
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• 2021

정합은 고유 좌표를 가지고 있는 점군을 전역 좌표로 변환하는 과정이다. 지역 정합은 계산 시간이 오래 걸리고 대략적인 위치를 맞춘 후 정밀 정합을 수행하고, 전역 정합은 정합에 이용할 대응점을 계산하고 한 번에 정합하기 때문에 일반적으로 지역 정합법에 비해 속도가 빠르고, 초기 위치에도 상관이 없다. 전역 정합 방법 중 고속 전역 정합법은 성능이 우수하여 많이 사용하는 방법 중 하나이다. 하지만 정합 정밀도와 속도를 높이기 위해서는 많은 매개변수가 필요하다. 본 논문에서는 이와 같은 매개변수들을 분석하고 실험하여 실제 정합 시 유효하게 작용하는 매개변수를 제안한다. 제안한 결과는 고속 전역 정합법을 활용해야 하는 경우 방향 설정에 도움이 될 것이다.

• 지역과문화
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• 제6권4호
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• pp.1-21
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• 2019

이 연구는 인문학과 지역문화의 관점에서 부산의 지역적 특성과 역사적 특성이 상호작용하여 탄생한 향토음식을 통해 부산의 장소적 특성을 살펴보았다. 장소는 단순히 좌표에 표기되는 공간상의 지점이 아니라 그 안에서 살아가는 인간의 경험과 정서적 면까지도 포함하는 의미체이다. 장소는 가시적 환경과 환경에 대한 인간의 반응인 문화가 혼합되어 이루어지는 것으로 장소에 대한 이해는 개인의 지리와 문화·역사까지를 이해할 수 있는 기반이 된다. 장소성과 함께 한 지역의 특수성을 말하는 것 중에 하나가 향토음식이다. 향토음식은 그 지역의 특성과 주민들의 선호에 따라 변화될 수 있어 고정불변한 것은 아니다. 부산의 향토음식은 부산이 위치한 장소적 특징을 반영하면서 부산의 역사적 체험까지를 함께 담고 있는 음식이라 할 수 있다. 장소성과 역사성을 가진 부산의 대표적인 향토음식은 다음과 같이 정리될 수 있다. 첫 번째로, 바다와 접해있는 항구로서의 장소적 특성을 잘 말해주고 있는 멸치회와 곰장어 구이이다. 두 번째로, 수산물과 곡물을 이용해서 만든 동래파전과 산성막걸리이다. 세 번째로, 일제강점기 때 새롭게 탄생한 어묵과 활어회이다. 그리고 마지막으로 1·4후퇴 때 부산으로 피난 내려와 정착해서 살던 피난민들이 만든 음식인 밀면과 돼지국밥이다. 한 지역을 대표하는 향토음식은 단순하게 먹고 즐기고 소비되는 상품으로서의 수준을 넘어 그 지역의 장소적 특성과 역사적 특성을 함께 담은, 즉, 그 지역의 문화적 특성을 잘 말해주는 하나의 상징물이라 할 수 있다. 또한 이러한 상징물은 한 지역의 특성을 살피고 정체성을 규정하는 데 중요한 근거가 될 수 있다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.75-80
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• 2002

The mainly used technique to rectify satellite images with distortion is to develop a mathematical relationship between the pixel coordinates on the image and the corresponding points on the ground. By defining the relationship between two coordinate systems, a polynomial model is designed and various linear transformations are used. These GCP based geometric correction has performed overall plane to plane mapping. In the overall plane mapping, overall structure of a scene is considered, but local variation is discarded. The highly variant height of region is resampled with distortion in the rectified image. To solve this problem this paper proposed the TIN-based rectification on a satellite image. The TIN based rectification is good to correct local distortion, but insufficient to reflect overall structure of one scene. So, this paper shows the experimental result and the analysis of each rectification model. It also describes the relationship GCP distribution and rectification model. We can choose a geometric correction model as the structural characteristic of a satellite image and the acquired GCP distribution.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1366-1371
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• 2003

Molecular dynamics (MD) simulations are conducted to investigate the thermophysical characteristics and the stability of liquid threads for various conditions. A cylindrical thread in the simulation domain is made of Lennard-Jones molecules. The surface tension of liquid threads can be determined from local densities, local normal and transverse components of the pressure force. In order to understand the effects of thread radii on surface tensions, the Tolman equation is modified on the basis of the cylindrical coordinates for prediction of surface tensions. Surface tensions calculated from the MD simulation agree with the prediction from the modified Tolman equation. In addition, surface tensions decrease linearly with increasing system temperature. For a binary system, the surface tension decreased linearly compared to that for a pure system with increasing binary ratio of solute molecules which have relatively large value of the affinity coefficient. For a fixed binary ratio, the surface tension increased slightly with the affinity coefficient and the maximum value appear around where the affinity coefficient is 1.5 and decreased rapidly for upper value of 1.5. In addition, the critical wavelengths of perturbations are proven to be directly proportional to the equimolar dividing radii of the liquid threads.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제2권1호
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• pp.5-21
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• 2008

In order to securely transmit multicast data packets in a mobile environment where frequent join/leave events are a characteristic of the environment, there is a need for a new secure and efficient group key management solution. We propose a secure group key generation/distribution solution providing scalability and reliability. Using this solution, when a mobile node, which is in a multicast session, enters a new domain, the agent of the domain joins the multicast session and coordinates its data packets with the mobile node. The agent encrypts and transmits subsequent data packets to the mobile node, using a local one-time pad key. This key is generated with FI sequences, enabling the mobile node to regenerate the same data packet, based on the information sent by the agent. Our performance analysis demonstrates that the proposed solution can significantly reduce the number of key generations and distributions, when it is applied to the hierarchical mobile IPv6 network.

• 한국측량학회지
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• 제9권2호
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• pp.1-8
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• 1991

정밀측지좌표의 계산, 탄도무기의 탄도계산 및 관성유도장치의 기준 방향설정 등에 영향을 주는 지오 이드형상은 지구 물리학 및 측지학에서 매우 중요하게 취급된다. 본 연구는 우리나라에 가장 적합한 지오이드 모델을 개발하는데 그 최종 목적이 있으며, 여러가지의 지오이드 결정 방법 중 가장 기초적이고 고전적인 천문측지 수준측량 및 곡면다항식 방법을 사용하여 표준오차 $\pm$0.49m 및$\pm$0.66m의 지역 지오이드를 얻을 수 있었으며, 최대 지오이드 경사는 약 22m~23m 정도임을 알 수 있었다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제10권6호
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• pp.711-729
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• 2018

This paper reports on the experimental investigations on the failure modes of ring-stiffened cylinder models subjected to external hydrostatic pressure. Nine models were welded from general structural steel. The shells were initially formed by cold-rolling, and flat-bar ring frames were welded to the shell. The hydrostatic pressure tests were conducted by using water as the medium in pressure chambers. The details of the preparation and main test were briefly explained. The investigation identified the consequence of the structural failure modes, including: shell yielding, local shell buckling between ring stiffeners, overall buckling of the shell together with the stiffeners, and interactive buckling mode combining local and overall buckling. In addition, the ultimate strengths were predicted by using existing design codes. Non-linear numerical computations were also conducted by employing the actual imperfection coordinates. Finally, accuracy and reliability of the predictions of design formulae and numerical were substantiated with the test results.

• Structural Engineering and Mechanics
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• 제13권2호
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• pp.135-154
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• 2002

This paper presents the convected material frame approach to study the nonlinear behavior of inelastic frame structures. The convected material frame approach is a modification of the co-rotational approximation by incorporating an adaptive convected material frame in the basic definition of the displacement vector and strain tensor. In the formulation, each discrete element is associated with a local coordinate system that rotates and translates with the element. For each load increment, the corresponding strain-displacement and nodal force-stress relationships are defined in the updated local coordinates, and based on the updated element geometry. The rigid body motion and deformation displacements are decoupled for each increment. This modified approach incorporates the geometrical nonlinearities through the continuous updating of the material frame geometry. A generalized nonlinear function is used to derive the inelastic constitutive relation and the kinematic hardening is considered. The equation of motion is integrated by an explicit procedure and it involves only vector assemblage and vector storage in the analysis by assuming a lumped mass matrix of diagonal form. Several numerical examples are demonstrated in close agreement with the solutions obtained by the ANSYS code. Numerical studies show that the proposed approach is capable of investigating large deflection of inelastic planar structures and providing an excellent numerical performance.

• Bulletin of the Korean Chemical Society
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• 제12권2호
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• pp.214-219
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• 1991

To study the effect of solvents and counterions in Z-DNA crystal of d(5BrC-G-5BrC-G-5BrC-G), we performed the local energy analysis and then molecular dynamics simulations. Since counterions raise serious caging problems in crystal simulations, it is very important to search for the possible positions before simulations. For this purpose, the local energy analysis was done for the whole crystal volume. It is shown from our simulation that counterions along with water molecules play a bridging role to bind adjacent oligomers so as to form the crystal. In this crystal, each water molecule bound to Gua-N2H, either directly or indirectly, hydrates the adjacent anionic phosphate oxygen, and thus assists Gua to be in a syn position. From the simulation, the average root-mean-square deviation of allthe DNA heavy atom coordinates from the X-ray data is $0.99{\AA}$ . The bases are less deviated from the X-ray positions than the phosphates. The temperature factors from the simulation are consistent with those from the X-ray refinement, showing that the phosphates are more mobile than the bases.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2003년도 추계학술발표회 논문집
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• pp.49-54
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• 2003

As of date, the cadastral information which is the utility to be computerized have not been identical with local autonomous entities and relational groups each other and updated real-time, therefore the relation group or the academic circles carried out in many researches on a cadastral map matching, but the cadastral maps have not been even occurred the expansion and contraction so that the theory arrangement doesn't seem simple as to a cadastral map matching. As being take such reality into consideration, We have to be based on $\boxDr$construction ministry of the rules for continuous map$\boxUl$ for a continuous cadastral map with using PBLIS data; so the operators use Autodesk Map 5 which added applications and match the neat line by the identical scale, the different scale, the district boundary and the origin according to the judgement myself We have the purpose to minimize the problem as analyzing the accuracy between the parcel coordinates If the matched map and ones of moved map.