• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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• pp.186-191
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• 1998

The first step in change detection in any SAR monitoring, including SAR interferometry, is the co-registration of the images. CCPs (Ground Control Points) for co-registration are usually detected manually, but for qualitative analyses of enormous volumes of data, some automation of the process will become necessary. An automated determination of common CCPs for the same path/row data is especially desirable. We selected the intersections of linear features as the candidates of common GCPs Very bright point targets, which are commonly used as GCPs, have the drawback of appearing and disappearing depending on the conditions of the observation. But in the case of linear features, some detailed elements may appear differently in some case, but the overall line-likeness will remain. In this study, we selected 18 common GCPs for a single-look JERS-1 SAR image of Omaezaki area in central Japan. Although the GCPs in the first image had to be selected either interactively or semi-automatically, the same GCPs in all other images were successively detected automatically using a tiny sub-image around each GCP and a dilated mask of each linear feature in the first image as the reference data.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권9호
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• pp.4336-4354
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• 2018

Fuzzy C-means (FCM) algorithm is a most usually technique for medical image segmentation. But conventional FCM fails to perform well enough on magnetic resonance imaging (MRI) data with the noise and intensity inhomogeneity (IIH). In the paper, we propose a Gamma correction conditional FCM algorithm with spatial information (GcsFCM) to solve this problem. Firstly, the pre-processing, Gamma correction, is introduced to enhance the details of images. Secondly, the spatial information is introduced to reduce the effect of noise. Then we introduce the effective neighborhood mechanism into the local space information to improve the robustness for the noise and inhomogeneity. And the mechanism describes the degree of participation in generating local membership values and building clusters. Finally, the adjustment mechanism and the spatial information are combined into the weighted membership function. Experimental results on four image volumes with noise and IIH indicate that the proposed GcsFCM algorithm is more effective and robust to noise and IIH than the FCM, sFCM and csFCM algorithms.

• 대한방사선기술학회지:방사선기술과학
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• 제22권1호
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• pp.49-53
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• 1999

To inquire its usefulness of the clinical application of intelligent replenishment system of automatic X-ray film processor based on film density, we processed the serial 300 sheets of radiographic film of chest [$14{\times}14"$, HR-C type] and bone [elbow & ankle($8{\times}10"$), skull($10{\times}12"$), hand & foot($11{\times}14"$), pelvis($14{\times}17"$), HR-G type, 68, 70, 77, 85 sheets respectively]. We analyzed the characteristic corves, relative speeds, average gradients and base plus fog densities every twenty five sheets. We also evaluated the developer and fixer replenishment volumes every that time. In the chest and bone radiograph two all, the characteristic curves were little change, and the relative speeds, average gradients and base plus fog densities were within the maximum control limits. The average developer replenishment volumes were about 43m1/sheet and 39m1/sheet respectively. It brings decreased results about 29% in comparison with the conventional replenishment system. In our experiences, we conclude that the intelligent replenishment system of automatic X-ray film processor based on film density maintains image quality consistently, decreases also the replenishment volumes. Therefore, this system will be resulted in economic and environmental effects, and solve problems of over and low replenishment volume.

• Journal of Computing Science and Engineering
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• 제6권1호
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• pp.1-11
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• 2012

Computed tomography (CT) images are widely used for the analysis of the temporal evaluation or monitoring of the progression of a disease. The follow-up examinations of CT scan images of the same patient require a 3D registration technique. In this paper, an automatic and robust registration is proposed for the rigid registration of 3D CT images. The proposed method involves two steps. Firstly, the two CT volumes are aligned based on their principal axes, and then, the alignment from the previous step is refined by the optimization of the similarity score of the image's voxel. Normalized cross correlation (NCC) is used as a similarity metric and a downhill simplex method is employed to find out the optimal score. The performance of the algorithm is evaluated on phantom images and knee synthetic CT images. By the extraction of the initial transformation parameters with principal axis of the binary volumes, the searching space to find out the parameters is reduced in the optimization step. Thus, the overall registration time is algorithmically decreased without the deterioration of the accuracy. The preliminary experimental results of the study demonstrate that the proposed method can be applied to rigid registration problems of real patient images.

• 한국조경학회지
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• 제19권3호
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• pp.55-71
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• 1991

The purpose of this thesis is to suggest objective basic data for the environmental design through the quantitative analysis of the visual quality included in the physical environment of Basemsagol valley sequence landscape. For this, visual volumes of physical elements have been evaluated by using the mesh analysis, spatial images structure of physical elements have been analyzed by factor analysis algorithm, and degree of visual quality have been measured mainly by questionnaires. Also, this study aims to understand semiotics and to grope the possibility of application to the sequence landscape assessment. A semiological approach suggests a new dimension in sequence landscape assessment, which is a contrast to the existing scientific evaluation methods. Result of this thesis can be summarized as follows. Visual volumes of the immediate vegetation, rock, bridge, road and distant vegetation are found to be the main factor determining the visual quality. Factors covering the spatial image of natural park sequence landscape have been found to be the overall synthetic evaluation, potentiality, natural quality, spatial, appeal and dignity. By using the control method for the number of factors, T.V. has been obtained as 40.22%. The characteristics of the semiological approach is qualitative, open, holistic, and experiential, whereas that of the scientific approach is quantitative, closed, reductive, and experimental.

• International Journal of CAD/CAM
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• 제9권1호
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• pp.111-120
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• 2010

In this paper, we propose a volume rendering method using grid computing for large-scale volume data. Grid computing is attractive because medical institutions and research facilities often have a large number of idle computers. A large-scale volume data is divided into sub-volumes and the sub-volumes are rendered using grid computing. When using grid computing, different computers rarely have the same processor speeds. Thus the return order of results rarely matches the sending order. However order is vital when combining results to create a final image. Job-Scheduling is important in grid computing for volume rendering, so we use an obstacle-flag which changes priorities dynamically to manage sub-volume results. Obstacle-Flags manage visibility of each sub-volume when line of sight from the view point is obscured by other subvolumes. The proposed Dynamic Job-Scheduling based on visibility substantially increases efficiency. Our Dynamic Job-Scheduling method was implemented on our university's campus grid and we conducted comparative experiments, which showed that the proposed method provides significant improvements in efficiency for large-scale volume rendering.

• Computers and Concrete
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• 제25권5호
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• pp.433-445
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• 2020

A method is proposed in this paper to estimate the workability of self-compacting concrete (SCC) in different mixing conditions with different mixers and mixing volumes by recording the mixing process based on deep learning (DL). The SCC mixing videos were transformed into a series of image sequences to fit the DL model to predict the SF and VF values of SCC, with four groups in total and approximately thirty thousand image sequence samples. The workability of three groups SCC whose mixing conditions were learned by the DL model, was estimated. One additionally collected group of the SCC whose mixing condition was not learned, was also predicted. The results indicate that whether the SCC mixing condition is included in the training set and learned by the model, the trained model can estimate SCC with different workability effectively at the same time. Our goal to estimate SCC workability in different mixing conditions is achieved.

• 대한공간정보학회지
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• 제3권2호
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• pp.151-158
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• 1995

Change detection기법은 영상에서 차이를 알아내기 위하여 가장 많이 사용되는 방법이며 다양한 영상환경에 사용된다. 수치지형모델과 수치영상은 같은 수치격자데이타 구조를 가지므로 Change detection기법을 수치지형모델에 적용할 측량결과의 표고데이타를 불규칙삼각형(TIN)으로부터 격자구조로 변환하고 수치지형모델화하여 구조물의 변형지점을 찾는데 사용함으로 많은 소모성 자재와 인력을 줄일 수 있었다. 그 결과를 가시화하여 건물의 변형이 발생한 지점과 변형향을 수치적으로 나타낼 수 있었다.

• 한국지능시스템학회논문지
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• 제24권5호
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• pp.518-528
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• 2014

본 논문에서는 4차원 시공간 (4D-ST, [x,y,z,t]) 특징을 이용하여 행동 방향을 인식하는 방법을 제안한다. 이를 위해 4차원 시공간 특징점 (4D-STIPs, [x,y,z,t])을 제안하였고, 이는 여러 다른 뷰에서 촬영한 이미지들로부터 복원된 3차원 공간 (3D-S, [x,y,z]) 볼륨으로부터 계산된다. 3차원 공간정보를 갖고 있는 3D-S 볼륨과 4D-STIPs는 2차원 공간 (2D-S, [x,y]) 뷰로 사영을 하여 임의의 2D-S 뷰에서의 특징을 생성해 낼 수 있다. 이 때, 사영 방향을 결정 할 수 있으므로, 학습 시 방향에 대한 정보를 포함하여 행동 방향을 인식 할 수 있다. 행동 방향을 인식하는 과정은 두 단계로 나눌 수 있는데, 우선 어떤 행동인지를 인식하고 그 후, 방향 정보를 이용하여 최종적으로 행동 방향을 인식한다. 행동 인식과 방향 인식을 위해, 사영된 3D-S 볼륨과 4D-STIPs은 각각 움직이는 부분과 움직이지 않는 부분에 대한 정보를 담고 있는 motion history images (MHIs)와 non-motion history images (NMHIs)로 구성된다. 이러한 특징들은 행동 인식을 위해, 방향 정보에 상관없이 같은 행동이면 같은 클래스로 분류되어 support vector data description (SVDD) 분류기로 학습되고, support vector domain density description (SVDDD)을 이용하여 인식된다. 인식된 행동에서 최종적으로 방향을 인식하기 위해 각 행동을 방향 클래스로 분류하여 SVDD 분류기로 학습하고 SVDDD로 인식한다. 제안된 방법의 성능을 보이기 위해서 INRIA Xmas Motion Acquisition Sequences (IXMAS) 데이터셋에서 제공하는 3D-S 볼륨을 사용하여 학습을 하고, 행동 방향 인식 실험이 가능한 SNU 데이터셋을 구축하여 인식 실험을 하였다.

• 복식문화연구
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• 제26권2호
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• pp.233-250
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• 2018

This study examined images typical to this city and explored ways to develop cultural products using these images. Researchers reviewed literature about fashion cultural products and related previous research, and then conducted a closed-ended survey to analyze universal fashion preferences. For the examination material, such a way was used as information data base and network review inside and outside the country, dissertation screen, and published media including separate volumes. The following are considering points in the developing process. First, the study identified design, color, price, practicality and quality as factors that should be taken into consideration when using the image of Gangneung. In particular, it determined that the image needs to reflect a modern sensibility while maximizing its representation of local culture. Second, Gangneung's symbolic image should incorporate the sea, Gyeongpo, and coffee. In other words, the sea, Gyeongpo, and coffee should receive top symbolic priority. Third, from a development perspective, the most appropriate items for displaying the image include t-shirts, keychains, umbrellas, or other accessories, since these items are easily available in terms of price. In sum, this study highlighted the necessity of reconsidering Gangneung's currents ymbolic image, suggesting that a new image should be developed. Developing a typical fashion cultural product image will enrich Gangneung's cultural industry and the distribution of newly designed products will improve the localeconomy.