• Journal of the Korean Geographical Society
• /
• v.41 no.2 s.113
• /
• pp.212-226
• /
• 2006

Surface data generally represent continuous distribution of geographical or social phenomena of a region in urban analysis. Instances include distribution of temperature, population of region, and various distributions related to human activities. When spatial data are given in the form of surface, surface comparison is required as a way of comprehending the surface change or the relationship between two surfaces. As for previous approaches of surface comparison, there are visualization, quantitative methods and qualitative method. All those approaches, however, show the difference between two surfaces in a limited way. Especially, they are not able to distinguish spatial difference between two surfaces. To overcome such problem, this paper proposes a method of comparing two surfaces in terms of their spatial structure. Main concept of the method comes from earth moving problem and the method is named minimum surface transformation, here. When a surface is transformed into another, total surface volume moved in the process of transformation should be the minimum. Both quantitative and spatial differences between two surfaces are evaluted by total surface volume moved and the distribution of moved surface volume of each cell respectively. The method is applied to hypothetical and actual data. From the former, it is understood that the method explains how two surfaces are quantitatively and spatially different. The result of the latter shows that moved total surface volume decreases as time goes by which fits the actual situation that population change rate gets smaller. Concerning the other measure of surface difference, the distribution of $X_{ij}$ describes detailed flow of surface volume than that of simply subtracting surface volume by indicating to what direction the population change occurs.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2009.05a
• /
• pp.1955-1959
• /
• 2009

본 연구에서는 토양층에서 지하수 수리경사와 주 흐름 방향을 산정하여 변동특성을 분석하고, 그 원인에 대해 고찰하였다. 연구부지는 부경대학교 환경연구동 앞 잔디밭이며, 2008년 10월 18일 ${\sim}$ 11월 1일의 기간 중 12일(10월 21, 28일은 관측 못함) 동안 24회 관측되었다. 관측된 지하수공은 9개공이며, 4 m ${\times}$ 4 m의 정방형으로 설계되었다. 지하수위에 의한 수리경사와 주 흐름 방향의 산정은 총 9가지 형태의 평면으로 가정하여 산정하였다. 수리경사와 주 흐름 방향을 산정하기 위한 평면은 모두 9가지 형태로 가정하였다. 첫 번째는 9개공 모두를 이용한 정방형 평면(TW), 두 번째는 6개공을 이용한 4가지 경우의 삼각형 평면(T1, T2, T3 및 T4), 세 번째는 6개공을 이용한 4가지 경우의 직사각형 평면(R1, R2, R3 및 R4)으로 가정하여 각각의 평면에서 수리경사와 주 흐름 방향을 산정하였다. 이상에서 가정된 9가지 평면에서 산정된 평균 수리경사는 0.0094(R2) ${\sim}$ 0.0123(T2)의 범위로 나타났으며, 9개공 모두를 이용한 평면(TW)에서의 평균 수리경사는 0.0109로 산정되었다. 관측기간 동안 T1과 T3 평면의 평균 주 흐름 방향은 각각 -84.9818과 -86.2487로서, 다른 7개 평면의 평균 주 흐름 방향이 79.7045(T4) ${\sim}$ 85.8405(TW)의 범위로 나타난 것과는 반대의 흐름 방향을 보였다. 이러한 결과는, 본 연구에 적용된 수리경사와 주 흐름 방향의 산정기법(Devlin, 2003)이 삼각형 형태의 평면에는 부적합할 수 있음을 보여주는 것이다. 관측기간 중 10월 12일에 내린 소량의 강우(12 mm)에 의한 수리경사와 주 흐름 방향의 변동은 크게 나타나지 않았다. 본 연구에서는 정방형, 삼각형 및 직사각형의 평면 토양층에서 지하수의 수리경사와 주 흐름 방향을 산정하여 전체 및 국부적인 부지에서의 차이를 파악하고, 평면의 형태에 따른 수리경사와 주 흐름 방향의 차이 또한 확인할 수 있었다.

• Korean Journal of Optics and Photonics
• /
• v.28 no.6
• /
• pp.339-345
• /
• 2017

The flatness of a reference flat plays an important role, from the calibration of an interferometer to the reference for a semiconductor or flat-panel display, etc. Especially if we order the flatness measurement outside Korea, we may spend more time and money. In this paper, we measured the flatness of a reference flat using a three-flat test, which is one of the absolute measurement methods, and calculated its measurement uncertainty. In the three-flat test we adopted, each flat is tested against another flat, with three unknown flats, using an interferometer. Among several three-flat tests, we adopted Griesmann's method which has a low measurement uncertainty and is less dependent on the experimental equipment. As a result, the measurement uncertainty was found to be less than 0.5 nm rms, which is very accurate for high-tech industrial applications.

• 한국방재학회:학술대회논문집
• /
• 2010.02a
• /
• pp.33.1-33.1
• /
• 2010

불특정다수의 사람들이 이용하는 숙박계시설이며, 자립피난이 곤란한 피난약자에 해당하는 환자 및 노약자, 임산부, 어린이가 대다수 이용하는 병원은 피난안전상 매우 불리한 용도의 건축물이라 할 수 있다. 따라서 본 연구에서는 실재병원의 건립 당시 평면계획과 실재 사용 중 평면을 조사하고, 이를 대상으로 본 연구의 선행연구에서 발표된 피난안전성의 평가법에 적용하여, 병원 평면의 변화에 따른 피난안전성의 변화를 정량적으로 나타내는 것으로, 불가피한 평면의 변경 시에 참고자료로 활용 될 수 있는 근거를 제시 하고자 한다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.23 no.4
• /
• pp.836-845
• /
• 1998

In this ppaer, the confguration of multi-layers of the image planes surrounding the current trace of inite width has been considered, and the shielding performance of image planes is analyzed with the parameters of the width and conductivity of the planes, and the distance between the current trace and the planes. The induced current distributions on the image planes have bgeen calculated by solving a set of electric field integral equations by the method of moments. To cacluate the current distribution on the planes effectively, a new method for dividing integral intervals is proposed.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
• /
• v.6 no.4
• /
• pp.28-36
• /
• 1995

The use of image planes can reduce effectively the radiated emissions from a printed circuit board. This work deals with the influence of image planes on radiation from current trace. The configu- rations of one and two layers of image planes on both sides of current trace are proposed. The radiated emissions of those configurations have been calculated by solving a set of electric field integral equations by the method of moments. The induced current distributions on image planes and the radiation patterns are analyzed for different configurations of image planes, the distance between current trace and image planes, and the frequency of signal current.

• Korea Real Estate Review
• /
• v.27 no.1
• /
• pp.17-32
• /
• 2017

The openness of residential space directly affecting lighting, view, and ventilation leads to the variation of open floor plan type in apartment construction project. This study intends to substantiate the effect to the apartment price by design property of open floor plan based on actual design information of apartment and price. The open floor plan type and associated design property, and actual transaction price of apartment have been considered as variables for analysis by the hedonic price function model and artificial neural networks model. Research findings indicate that the openness affects the price of apartment positively and the three sides open plan is the most preferred with the highest price. This study aims to provide the implication to the developer in planning and design stage of apartment and the purchaser seeking the suitable price by floor plan design.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.14 no.4
• /
• pp.321-336
• /
• 2012

The shear behavior at the particle/surface interface such as rock joint can determine the mechanical behavior of whole structure. Therefore, a fundamental understanding of the mechanisms governing its behavior and accurately estimation of the interface strength is essential. In this paper, PFC, a numerical analysis program of discrete element method was used to investigate the effects of the surface roughness crushing on interface strength. The surface roughness was characterized by smooth, intermediate, and rough surface, respectively. Particle shape was classified into one ball model of circular shape and 3 ball model of triangular shape. The surface shape was modelled by wall model of non-crushing surface and ball model of crushing surface. The results showed that as the bonding strength of ball model decreases, lower interface strength is induced. After the surface roughness crushing was occurred, the interface strength tended to converge and higher bonding strength induced lower surface roughness crushing. Higher friction angle was induced in wall model and higher surface roughness induced the higher friction angle. From these findings, it is verified that the surface roughness and surface roughness crushing effect on the particle/surface interface shear behavior.

• Journal of Digital Convergence
• /
• v.14 no.11
• /
• pp.319-324
• /
• 2016

In the case of robot and Argument Reality applications using a camera in environments, a technology to estimate planes is a very important technology. A RGB-D camera can get a three-dimensional measurement data even in a flat which has no information of the texture of the plane;, however, there is an enormous amount of computation in order to process the point-cloud data of the image. Furthermore, it could not know the number of planes that are currently observed as an advance, also, there is an additional operation required to estimate a three dimensional plane. In this paper, we proposed the real-time method that decides the number of planes automatically and estimates the three dimensional plane by using the continuous data of an RGB-D camera. As experimental results, the proposed method showed an improvement of approximately 22 times faster speed compared to processing the entire data.

• The Journal of Korean Institute of Next Generation Computing
• /
• v.15 no.4
• /
• pp.80-88
• /
• 2019

Software Defined Networking (SDN) is the future network paradigm of decoupling control and data functions. In SDN structure, it is hard to address scalability in case of large-scale networks because single controller managed thousands of switches in a centralized fashion. Most of previous studies have focused on horizontal scalability, where distributed controllers are assigned to network devices. However, they have abstracted the control plane and the application plane into a single controller. The layer of the common SDN architecture is divided into data plane, control plane, and application plane, but the control plane and application plane have been modeled as a single controller although they are logically separated. In this paper, we propose a analytical traffic model considering the both application plane and control plane based on queuing theory. This model can be used to address scalability issues such as controller placement problem without complicated simulations.