• 대기
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• 제19권2호
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• pp.107-125
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• 2009

Statistical downscaled surface temperature datasets by employing the cyclostationary empirical orthogonal function (CSEOF) analysis and multiple linear regression method are examined. For evaluating the efficiency of this statistical downscaling method, monthly surface temperature of the ECMWF has been downscaled into monthly temperature having a fine spatial scale of ~20km over the Korean peninsula for the 1973-2000 period. Monthly surface temperature of the ECHOG has also been downscaled into the same spatial scale data for the same period. Comparisons of temperatures between two datasets over the Korean peninsula show that annual mean temperature of the ECMWF is about $2^{\circ}C$ higher than that of the ECHOG. After applying to the statistical downscaling method, the difference of two annual mean temperatures reduces less than $1^{\circ}C$ and their spatial patterns become even close to each other. Future downscaled data shows that annual temperatures in the A1B scenario will increase by $3.5^{\circ}C$ by the late 21st century. The downscaled data are influenced by the ECHOG as well as observation data which includes effects of complicated topography and the heat island.

• 대한의용생체공학회:의공학회지
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• 제17권2호
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• pp.165-172
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• 1996

A scanning slot digital mammography system Luing a plastic scintillating fiber screen (SFS) is currently being developed To improve the x-ray interaction efficiency and absorption efficiency of an SFS, high Z elements can be added into the scintillating fiber core. In this paper, we investigated theoretically the zero spatial frequency detective quantum efficiency, DQE(0), and modulation transfer function, MTF(f), of three 2 cm thick SFSs made of polystyrene, polystyrene loaded with 5% by weight of lead, and polystyrene Loaded with 10% by weight of tin scintillating fibers. X-ray interaction efficiency, scintillating light intensity distributions and line spread functions were generated using Monte Carlo simulation. DQE(0) and MTF(f) were computed for x-ray energies ranging from 15 to 50 keV. Loading high Z elements into the SFS markedly increased the DQE(0). For x-ray energies used for mammovaphy, DQE(0) values of both high Z element loaded SFSs are about a factor of three higher than the DQE(0) of an Min-R screen. At mammographic x-ray energies, MTF(f) values of all three SFSs are Venter than 50% at 25 Ip/mm spatial frequency, and were found to be dominated by the 20 um individual scintillating fiber diameter used The results show that both hiP DQE(0) and spatial resolution can be achieved with the high Z element loaded SFSs, which make these SFSs attractive for use in a scanning slot detector for digital mammography.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권6호
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• pp.3121-3143
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• 2019

Segmentation plays an important role in the field of image processing and computer vision. Intuitionistic fuzzy C-means (IFCM) clustering algorithm emerged as an effective technique for image segmentation in recent years. However, standard fuzzy C-means (FCM) and IFCM algorithms are sensitive to noise and initial cluster centers, and they ignore the spatial relationship of pixels. In view of these shortcomings, an improved algorithm based on IFCM is proposed in this paper. Firstly, we propose a modified non-membership function to generate intuitionistic fuzzy set and a method of determining initial clustering centers based on grayscale features, they highlight the effect of uncertainty in intuitionistic fuzzy set and improve the robustness to noise. Secondly, an improved nonlinear kernel function is proposed to map data into kernel space to measure the distance between data and the cluster centers more accurately. Thirdly, the local spatial-gray information measure is introduced, which considers membership degree, gray features and spatial position information at the same time. Finally, we propose a new measure of intuitionistic fuzzy entropy, it takes into account fuzziness and intuition of intuitionistic fuzzy set. The experimental results show that compared with other IFCM based algorithms, the proposed algorithm has better segmentation and clustering performance.

• 건축역사연구
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• 제17권4호
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• pp.83-95
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• 2008

This study was firstly to reflect upon the background of the generation and the urban spatial value and significance of the medieval plaza. The main aim of this study was to extract the spatial determinants which give the great influence on the formation of the medieval plaza and in addition the endogenous rules and aesthetical grounds regarding the respective elements. Especially they could be applied to the design guideline. They are dimension(volume and scale), shape, elevation as the morphological elements and enclosure, proportion, grade difference, spatial sequence and plaza group as the spatial determinants and visual sequence, visual or spatial boundary, approaching axis and perspective effect as the aesthetic and visual elements and function(use), human behaviour as the social-behavioral elements and otherwise, for instance, plaza furniture, ground decoration and vegetation. This study was intended to analyze each elements based on the classical historical literatures and to suggest the planning conditions for composing the ideal plaza referring to the cases and literature review on the medieval plaza and finally is expected to contribute to the plaza design methodology.

• 한국공간정보시스템학회 논문지
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• 제2권1호
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• pp.63-72
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• 2000

본 연구에서는 국가지리공간정보의 유통망의 구성 방안을 제시하였다. 국가지리공간정보의 유통망의 구성요소를 유통망 게이트웨이, 유통노드, 공간데이터 서버, 통신망, 관련 규약과 표준 그리고 사용자의 여섯가지로 나누고, 구성요소 각각의 역할과 상호관계에 대하여 기술하였다. 제시된 방안에 따라 국가지리공간정보 유통체계를 구축하여 활용함으로써 지리공간정보의 중복 구축을 방지하고, 지리공간정보의 가치를 높이며, 민간 사업자들이 지리공간정보 데이터베이스의 구축에 적극적으로 참여할 수 있도록 유도할 수 있으며 나아가 지리공간정보의 구축, 유통 및 활용 사업을 새로운 정보통신의 기반 산업으로 자리잡게 할 수 있을 것이다.

• 한국실내디자인학회논문집
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• 제16권5호
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• pp.22-29
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• 2007

In the face of the new dimension of the developed technology $L{\acute{a}}szl{\acute{o}}$ Moholy-Nagy, a master of 'the Bauhaus Akademie', made an effort to constitute the integrated life of the intellectual and the emotional by translating the experiences of the new technology Into the emotional language and the cultural realities. As an artist who criticized in the constructivist ethos the conception of the image as the imitation and brought the Image movements into relief Moholy-Nagy groped for a new expressive idea that can be called as 'the idea of the non-representational spatial expression' in which the expressive elements interact one another. His idea of the non-representational spatial expression that is made up of the pure forms of the nature, the direct colors and the spatial elements is oriented to incorporate the modern realities, i.e. the space experiences as the complicated sensory workings and the new technology as the measure of the human thinking, and further to see where they will move to. This study is on the one hand purposed to explicate the fundamental idea of the non-representational spatial expression that was poorly illuminated in spite of its importance in the respects of the design and art history, on the other to re-actualize the implications of the space-design which are contained in it.

• 한국철도학회논문집
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• 제12권5호
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• pp.656-662
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• 2009

일반적으로 교통수단선택 모형은 이용자의 인구 및 개인통행특성 등을 반영한 수단별 선호도를 효용함수로 구축하여 분석하고 있다. 본 연구에서는 이용자의 출발지에 대한 공간적 연관성을 수단선택모형에 고려한 방법을 제시하였다. 이를 위하여 공간적 연관성을 포함하는 공간로지스틱 회귀모형을 고려하였다. 신뢰성있는 추정값을 얻기 위해 베이지안 기법을 적용하였으며 이 연구에서 제시한 방법론은 수단선호도 조사가 이루어지지 않은 지역에 대해서도 수단분담률을 추정할 수 있을 것으로 기대된다.

• Wind and Structures
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• 제16권5호
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• pp.433-455
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• 2013

A phase delay spectrum model towards the representation of spatial coherence of stochastic wind fields is proposed. Different from the classical coherence functions used in the spectral representation methods, the model is derived from the comprehensive description of coherence of fluctuating wind speeds and from the thorough analysis of physical accounts of random factors affecting phase delay, building up a consistent mapping between the simulated fluctuating wind speeds and the basic random variables. It thus includes complete probabilistic information of spatial stochastic wind fields. This treatment prompts a ready and succinct scheme for the simulation of fluctuating wind speeds, and provides a new perspective to the accurate assessment of dynamic reliability of wind-induced structures. Numerical investigations and comparative studies indicate that the developed model is of rationality and of applicability which matches well with the measured data at spatial points of wind fields, whereby the phase spectra at defined datum mark and objective point are feasibly obtained using the numerical scheme associated with the starting-time of phase evolution. In conjunction with the stochastic Fourier amplitude spectrum that we developed previously, the time history of fluctuating wind speeds at any spatial points of wind fields can be readily simulated.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.880-884
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• 2002

According to the development of computer technology, especially in 3D graphics and visualization, the interest for 3D GIS has been increasing. Several commercial GIS softwares are ready to provide 3D function in their traditional 2D GIS. However, most of these systems are focused on visualization of 3D objects and supports few analysis functions. Therefore in this paper, we design not only a spatial operation processor which can support spatial analysis functions as well as 3D visualization, but also implement a prototype to operate them. In order to support interoperability between the existing models, the proposed spatial operation processor supports the 3D spatial operations based on 3D geometry object model which is designed to extend 2D geometry model of OGIS consortium, and supports index based on R$^*$-Tree. The proposed spatial operation processor can be applied in 3D GIS to support 3D analysis functions.

• 대한원격탐사학회지
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• 제32권1호
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• pp.61-65
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• 2016

Importance of remote sensing for surface is increased than past. So many countries try to many ways to retrieve surface reflectance. In this study, we study a Bidirectional Reflectance Distribution Function (BRDF) to retrieve surface reflectance. We apply BRDF using observed surface reflectance of SPOT/VEGETATION (VGT-S1) and angular data to get Bidirectional Reflectance Distribution (BRD) coefficients for calculating scattering. And then we apply BRDF in the opposite direction with BRD coefficients and angular data to retrieve Background Surface Reflectance (BSR). The range of BSR is not over $0.4{\mu}m$ (blue), $0.45{\mu}m$ (red), $0.55{\mu}m$ (NIR). And for validation we compare BSR with VGT-S1, there are bias is from 0.0116 to 0.0158 and RMSE is from 0.0459 to 0.0545. As a result, we confirm that BSR is similar to VGT-S1.