• Title/Summary/Keyword: Scale-space

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Obtaining the driving scale of turbulence from observations

  • Cho, Jungyeon
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.1
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    • pp.56.2-56.2
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    • 2017
  • To maintain turbulence in astrophysical fluids, driving is required. Constraining the driving scale of turbulence is important to identify the driving mechanism and also to obtain more accurate turbulence statistics from observations. We discuss how to obtain the driving scale of turbulence from observations. First, we explain the method to obtain the driving scale from the standard deviation of centroid velocity (i.e. the first moment of the line profile). Second, we discuss other techniques to obtain the driving scale.

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No-reference Image Blur Assessment Based on Multi-scale Spatial Local Features

  • Sun, Chenchen;Cui, Ziguan;Gan, Zongliang;Liu, Feng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.10
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    • pp.4060-4079
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    • 2020
  • Blur is an important type of image distortion. How to evaluate the quality of blurred image accurately and efficiently is a research hotspot in the field of image processing in recent years. Inspired by the multi-scale perceptual characteristics of the human visual system (HVS), this paper presents a no-reference image blur/sharpness assessment method based on multi-scale local features in the spatial domain. First, considering various content has different sensitivity to blur distortion, the image is divided into smooth, edge, and texture regions in blocks. Then, the Gaussian scale space of the image is constructed, and the categorized contrast features between the original image and the Gaussian scale space images are calculated to express the blur degree of different image contents. To simulate the impact of viewing distance on blur distortion, the distribution characteristics of local maximum gradient of multi-resolution images were also calculated in the spatial domain. Finally, the image blur assessment model is obtained by fusing all features and learning the mapping from features to quality scores by support vector regression (SVR). Performance of the proposed method is evaluated on four synthetically blurred databases and one real blurred database. The experimental results demonstrate that our method can produce quality scores more consistent with subjective evaluations than other methods, especially for real burred images.

A Study on The Characteristics of Interior Design In Design Hotels - Focusing on Tony Chi's Works - (디자인 호텔에 나타난 실내디자인 표현특성 - 토니 치의 작품을 중심으로 -)

  • Kim, Sunyoung
    • Korean Institute of Interior Design Journal
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    • v.26 no.3
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    • pp.25-33
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    • 2017
  • The purpose of this study is to analyze the characteristics of interior space in his design hotel through the analysis of Tony Chi 's work and to present the direction of the design direction of the interior space of the design hotel in the future based on the results. The results are summarized as follows. First, the characteristics of the interior space of Tony Chi are divided into visual balance, repetitive rhythm, symbolic emphasis, exaggerated scale, design harmony, and physical borderlessness. Second, the spatial composition through visual balance was consistently shown in all cases, mainly by arranging elements such as furniture and lighting symmetrically. Third, the spatial composition through repetitive rhythm did not show its characteristics at the beginning of the works, but gradually appeared as repetitive rhythm expression using bold pattern. Fourth, Toni Chi constantly expressed the space composition through symbolic emphasis during the planning of the design hotel. Fifth, the exaggerated scale was mainly used to express the architectural detail vertically according to the height of the ceiling to express a grand space and appear in many works. Sixth, Toni Chi consistently expressed the composition of space through the harmony of design of oriental and western cultures, classical and modern designs in all cases. Seventh. In order to provide curiosity induction and aesthetic experience, spatial composition through physical borderlessness was used.

An Efficient Vehicle Parking Detection Method Using Gray Scale Images (그레이 스케일 이미지를 이용한 효율적인 주차검출 방법)

  • Park, Ho-Sik;Bae, Cheol-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.10C
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    • pp.629-634
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    • 2011
  • Empty space in the parking lot of the parking space to analyze the effective use of technology and transportation may be useful in the jungle, However, conventional analytical methods impractical parking space or need a fast processing speed. In this paper, real-time parking, so parking monitoring methods for detection is proposed. Gray-level images using the proposed method to determine whether the parking and the parking space was used to analyze. To verify the performance of the proposed method in an outdoor parking lot 129 video capture and analysis of experimental results in 98.5% of the parking space, parking space, the success of the proposed method was proved to be effective in the analysis.

A Study on the Distribution Specific Characteristics about Each Group of Exhibition Space on Museum through Multivariate Analysis - Focused on Establishment of Quantitative Analysis Characteristics and Main Component Analysis - (다변량해석에 의한 박물관 전시공간의 그룹별 분포특성 - 정량적 분석지표의 설정과 주성분분석을 중심으로 -)

  • Park Moo-Ho;Cho Jae-Wook;Lim Che-Zinn
    • Korean Institute of Interior Design Journal
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    • v.13 no.6
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    • pp.132-139
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    • 2004
  • This study is to a question in argument that existing theses about a trait spatial configuration of exhibition space were analyzed without appropriateness verification of analysis characteristics. Firstly, through theoretical studies of established thesis, validity twenty analysis characteristics was chosen by making an investigation into existing analysis characteristics. Secondly, through a subject of our investigation, forty-two exhibition space of nineteen museums and art museum at home and abroad, a distribution map of exhibition space was analyzed by multivariate analysis. As a result of this study : 1) Nine analysis characteristics which extracted through multivariate analysis was the principal analysis characteristics. 2) A scale was important characteristic for the classification of museum therefore a degree of space perception was ought to compare every one of similar scale museum. 3) When comparing a trait of spatial configuration at exhibition space, these characteristics came into effect on middle sized museums. 4) It was visually confirmed a trait of spatial configuration of each group between museum and art museum

Storm-Time Behaviour of Meso-Scale Field-Aligned Currents: Case Study with Three Geomagnetic Storm Events

  • Awuor, Adero Ochieng;Baki, Paul;Olwendo, Joseph;Kotze, Pieter
    • Journal of Astronomy and Space Sciences
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    • v.36 no.3
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    • pp.133-147
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    • 2019
  • Challenging Minisatellite Payload (CHAMP) satellite magnetic data are used to investigate the latitudinal variation of the storm-time meso-scale field-aligned currents by defining a new metric called the FAC range. Three major geomagnetic storm events are considered. Alongside SymH, the possible contributions from solar wind dynamic pressure and interplanetary magnetic field (IMF) $B_Z$ are also investigated. The results show that the new metric predicts the latitudinal variation of FACs better than previous studies. As expected, the equatorward expansion and poleward retreat are observed during the storm main phase and recovery phase respectively. The equatorward shift is prominent on the northern duskside, at ${\sim}58^{\circ}$ coinciding with the minimum SymH and dayside at ${\sim}59^{\circ}$ compared to dawnside and nightside respectively. The latitudinal shift of FAC range is better correlated to IMF $B_Z$ in northern hemisphere dusk-dawn magnetic local time (MLT) sectors than in southern hemisphere. The FAC range latitudinal shifts responds better to dynamic pressure in the duskside northern hemisphere and dawnside southern hemisphere than in southern hemisphere dusk sector and northern hemisphere dawn sector respectively. FAC range exhibits a good correlation with dynamic pressure in the dayside (nightside) southern (northern) hemispheres depicting possible electrodynamic similarity at day-night MLT sectors in the opposite hemispheres.

An Analysis on the Relationship of Architectural Features and Composition Elements for Structure Planning in School Gymnasium (학교체육관의 구조계획을 위한 구조시스템 구성요소의 변화와 건축특성의 영향분석)

  • Lee, Juna
    • Journal of the Korean Institute of Educational Facilities
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    • v.26 no.5
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    • pp.25-36
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    • 2019
  • School gymnasium is a multi-purpose large space building for various events and physical education activities, and is a facility that requires an approach to the desirable structural design, besides mechanical problems of structure against loads. For the integrated structure design concerning the architectural features, the major considerations of gymnasium planning that are the internal and external shape of the gymnasium, the space scale with structure members, the structural efficiency by members weight reduction and openness of the gymnasium space will have to take into account in the structural planning. From this point of view, the several cases of the school gymnasium were investigated and the parametric analyses were performed to the models using the various structural system. The parameters were the composition elements of structure system that are profile of structure, rigidity of member, connection and anchorage and stability. At the result, It was presented that the profile of structure member was the most influential factor to structural efficiency and the effect of the form and space of gymnasium. Also the design informations of structure design having the various feature of form and space were presented for the initial gymnasium planning.

Longitudinal Modal Analysis of a LOX-filled Tank Using the Virtual Mass Method

  • Lee, SangGu;Sim, JiSoo;Shin, SangJoon;Kim, Youdan
    • International Journal of Aeronautical and Space Sciences
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    • v.18 no.4
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    • pp.807-815
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    • 2017
  • For liquid rocket engine(LRE)-based space launch vehicles, longitudinal instability, often referred to as the pogo phenomenon in the literature is predicted. In the building block of system-level task, accurate dynamic modeling of a fluid-filled tank is an essential. This paper attempts to apply the virtual mass method that accounts for the interaction of the vehicle structure and the enclosed liquid oxygen to LOX-filled tanks. The virtual mass method is applied in a modal analysis considering the hydroelastic effect of the launch vehicle tank. This method involves an analysis of the fluid in the tank in the form of mass matrix. To verify the accuracy of this method, the experimental modal data of a small hemispherical tank is used. Finally, the virtual mass method is applied to a 1/8-scale space shuttle external tank. In addition, the LOX tank bottom pressure in the external tank model is estimated. The LOX tank bottom pressure is the factor required for the coupling of the LOX tank with the propulsion system. The small hemispherical tank analysis provides relatively accurate results, and the 1/8-scale space shuttle external tank provides reasonable results. The LOX tank bottom pressure is also similar to that in the numerical results of a previous analysis.

Lubrication of Space Systems by Tribo-coating

  • Kato, Koji
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2002.10b
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    • pp.7-8
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    • 2002
  • It is a time to introduce a concept of lubrication to space systems. Minimum amount of lubricant should be supplied to a contact interface instead of preparing too much lubricant on surfaces of the earth. In situ controllable lubrication method is wanted to overcome unexpected tribo-troubles in space. Tribo-coating, which forms a thin solid film in nm-scale by vacuum deposition during friction, is a promising lubrication method for space.

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