• Title/Summary/Keyword: Shape Space

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Polarization of Rayleigh Scattered Lyα in Active Galactic Nuclei

  • Chang, Seok-Jun;Lee, Hee-Won;Yang, Yujin
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.70.3-70.3
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    • 2016
  • Active galactic nuclei (AGNs) typically show a non-thermal continuum locally represented by a power-law and many prominent emission lines in the UV and optical regions. AGNs are classified by two types, where Type I AGNs exhibit both broad and narrow lines and only narrow lines are observed in Type 2 AGNs. The unification models of AGNs invoke the existence of a molecular torus just outside of the broad line region. In the presence of a high column HI region associated with the molecular torus, we propose that significant fraction of broad line photons near Lyman series can be scattered by atomic hydrogen in the torus. In particular, $Ly{\alpha}$ being the strongest emission line, strong linear polarization may develop around $Ly{\alpha}$ through Rayleigh scattering. We adopt a Monte Carlo technique to investigate the polarized transfer of $Ly{\alpha}$ in a thick HI region with the shape of a torus. We consider the range of HI column density N_HI = 1020-23 with fixed geometric parameters of the torus such as the inner and outer radii and the height. We present the polarized spectra and angular distribution of Rayleigh scattered radiation around $Ly{\alpha}$. We find that the $Ly{\alpha}$ core part is polarized in the direction perpendicular to the symmetry axis whereas in the far wing part it is polarized in the parallel direction. It is concluded that the unification of AGNs implies that $Ly{\alpha}$ can be uniquely polarized through Rayleigh scattering.

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A Simple Constitutive Model for Soil Liquefaction Analysis (액상화 해석을 위한 간단한 구성모델)

  • Park Sung-Sik;Kim Young-Su;Byrne P. M;Kim Dae-Man
    • Journal of the Korean Geotechnical Society
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    • v.21 no.8
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    • pp.27-35
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    • 2005
  • Several damages due to large displacement caused by liquefaction have been reported increasingly. Numerical procedures based on effective stress analysis are therefore necessary to predict liquefaction-induced deformation. In this paper, the fully coupled effective stress model called UBCSAND is proposed to simulate pore pressure rise due to earthquake or repeated loadings. The proposed model is a modification of the simple perfect elasto-plactic Mohr-Coulomb model, and can simulate a continuous yielding by mobilizing friction and dilation angles below failure state. Yield function is defined as the ratio of shear stress to mean normal stress. It is radial lines on stress space and has the same shape of Mohr-Columob failure envelope. Plastic hardening is based on an isotropic and kinematic hardening rule. The proposed model always causes plastic deformation during loading and reloading but it predicts elastic unloading. It is verified by capturing direct simple shear tests on loose Fraser River sand.

Personalization of Detached Houses in the Back-to-countryside Community Village - Case Study of the 'Jagun-Maul' in Namwon - (귀촌형 공동체마을 단독주택의 개성화 - 남원 '작은마을'의 사례연구 -)

  • Park, Kyoung-Ok;Lee, Sang-Un;Ryu, Hyun-Soo;Hwang, Jin-A
    • Journal of the Korean housing association
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    • v.23 no.1
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    • pp.79-88
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    • 2012
  • The purpose of this study is to determine the personalizing characteristics of detached housing that reflect the housing needs according to the residents' participation in the back-to-countryside community village. For this study, 15 households of Jagun-maul at Namwon in Jeonbuk provided responses to the semi-structured questionnaire on housing consciousness, housing needs, and views on lifestyle. In addition, 15 plans were analyzed about the shape of the plan, the composition of LDK, the type of access, and the type of special space. The results were as follows. 1) The number of households under the elementary education stage was larger than the number of households above the middle education stage. Most of the households revealed the housing consciousness of 'house as resting place'. Households under the elementary education stage showed a housing consciousness for family-oriented life and households above the middle education stage showed a housing consciousness to interact with neighbors. 2) Households under the elementary education stage preferred LK style while households above the middle education stage preferred LDK style. Most of the floor plans had a front entrance and sliding door for the access from living room to garden. 3) Special spaces such as a loft, 'Ondolbang' (room with underfloor heating), study, maru, 'Toenmaru' (narrow wooden porch), family room, workroom, and toilet with outside door were arranged on each floor plan.

Analysis of Semi-Rigid Connections on 3D Floating Structures (3차원 플로팅 구조물의 반강접 접합부 해석)

  • Park, Jong-Seo;Song, Hwa-Cheol
    • Journal of Navigation and Port Research
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    • v.36 no.3
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    • pp.175-180
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    • 2012
  • The shape of floating superstructure is the same as other buildings, but the foundation is based not on land but on a floating body. Unlike inland structures, they are largely influenced by the wave load. Deformation of the floating pontoon due to the wave loads affects the connection, which in turn causes problems related to the habitability and safety to the superstructure users. Accordingly, this study conducted elastic analysis regarding rigid connection and semi-rigid connection by the integration analysis that combined together the superstructure and pontoon of the 3-D floating structure. Moreover, this study investigated the results of the separation analysis excluding pontoon and the integration analysis. In addition, elasticity analysis was used to divide up the wave loads cases, and to classify the moment and displacement of the structure depending on connection following the changes in the wave loads.

Uniform Color Image Transformation based on Color Cluster Model (칼라 클러스터 모델에 근거한 균일 칼라 영상 변환)

  • Lee, Jeong-Hwan;Park, Se-Hyeon;Kim, Jung-Su
    • The Transactions of the Korea Information Processing Society
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    • v.3 no.6
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    • pp.1646-1657
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    • 1996
  • This paper presents a color transformation method based on a uniform color image model. Firstly, color variation factors are grouped into identical (multiplicative) factor and independent(additive) one for the color model, and they are modelled by the Gaussian function. The shape of a color cluster in (R, G, B) feature space is an ellipsoid whose elongated major axis correspond to the direction of mean vector. Secondly, the transformation of a color cluster using the model is studied. A transformation method for three dimensional coordinated is described. The proposed method is applied to artificial and natural color images. By the result of experiments, the elongated major axis of each cluster making up the transformed color image aggress with the direction of its mean vector.

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Error analysis of acoustic target detection and localization using Cramer Rao lower bound (크래머 라오 하한을 이용한 음향 표적 탐지 및 위치추정 오차 분석)

  • Park, Ji Sung;Cho, Sungho;Kang, Donhyug
    • The Journal of the Acoustical Society of Korea
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    • v.36 no.3
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    • pp.218-227
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    • 2017
  • In this paper, an algorithm to calculate both bearing and distance error for target detection and localization is proposed using the Cramer Rao lower bound to estimate the minium variance of their error in DOA (Direction Of Arrival) estimation. The performance of arrays in detection and localization depends on the accuracy of DOA, which is affected by a variation of SNR (Signal to Noise Ratio). The SNR is determined by sonar parameters such as a SL (Source Level), TL (Transmission Loss), NL (Noise Level), array shape and beam steering angle. For verification of the suggested method, a Monte Carlo simulation was performed to probabilistically calculate the bearing and distance error according to the SNR which varies with the relative position of the target in space and noise level.

Implementation of the Vehicle Antenna for the AM/FM/TDMB/GPS Receiver (AM/FM/TDMB/GPS 수신용 전장 안테나 제작)

  • Kim, Joo-Man;Son, Tae-Ho
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.8 no.5
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    • pp.105-113
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    • 2009
  • In this paper, a vehicle antenna for AM, FM, TDMB, GPS systems was designed and implemented. AM antenna loaded into small space of shark shape was designed by ferrite turn style antenna. For the FM and TDMB antenna, folded monopole antenna which helical is folded was applied. GPS antenna for achieving characteristics both bandwidth and gain improvement was designed microstrip patch that has air substrate and fractal structure. Receiving signal strengths by the measurement were presented for the AM, FM and TDMB antenna. AM signal strength was -65.7dBm, this strength is almost as same conventional pole antenna as -63.4dBm. It can be replaced conventional pole or glass antenna by the studied antenna. Signal strengths for FM and TDMB were -55.66 and -43.50dBm at center frequency, they are 5~10dB higher than conventional antenna. Measurements of bandwidth and gain for the GPS antenna showed 135 MHz under VSWR 2 : 1 and 4.31dBi, gains over GPS band were 3~5dB higher than ceramic patch antenna.

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A Study on The relocation plan and architectural characteristics of 18th century's Jongtaek based on the analysis of Hakbong Gado (학봉종택 가도(家圖)의 분석을 통한 18세기 종택의 이건계획 및 건축적 특성)

  • Ryu, Kee-Weon;Kim, Ki-Joo
    • Journal of architectural history
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    • v.18 no.3
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    • pp.7-25
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    • 2009
  • Hakbongjongtaek(The head house of Uisong Kim family, 鶴峯宗宅), firstly built in the early 17th century, was moved to its neighboring place in the late 18th century. The man who led the relocation(移建) of the house was the eldest grandson of the family, Jong-soo, Kim. He made and overall plan and also participated in building the house. There remain four Gados(family paintings, 가도(家圖)) related to the relocation plan. This paper aims to make an analysis of these Gados, and through analysis, to find what was the essential poing of the relocation plan and how the point was represented in the paintings. The result of analysis is as follows: 1. The main focus of relocation plan was the form of Anchae(the inner house). Anchae was designed as asymmetrical form, and restricted to four kan. Only Andaechung needed to be 6 kan size for religious ceremonies. 2. For the design of Sarangchae, the displacement of large Sarangbang and small Sarangbang was an important issue. There were two ways of layout: parallel type and facing type. The latter was chosen. 3. The representation and techniques of Gado is quite concrete, in spite of differences among them. The expression of doors, windows, attic and kitchen was based on the understanding of space. Also the spatial division, which was expressed line on the grid, was based on the scaled ruler. As we've seen before, painting the relocation plan was a kind of endeavors to make the housing type as a realization of Garye. Also, we can find out that role of the eldest grandson of the family was quite important to carry out the plan. As well as, it was meaningful to examine Sadaebu (the aristocrat of Chosun)'s perception of housing.

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A Study on the Origin and Form of Pagodas in Myanmar (미얀마 불탑의 기원과 형식 유래에 대한 고찰)

  • Cheon, Deuk-Youm;Yeom, Seung Hoon
    • Journal of architectural history
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    • v.27 no.2
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    • pp.63-78
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    • 2018
  • Pagodas in Myanmar can be largely divided into Zedi and Pato. Zedi is a developed form of the early domed pagodas in India and Sri Lanka, which can be found in the introduction of Buddhism in Myanmar and the comparison of early pagodas in India, Sri Lanka and Myanmar. On the other hand, Pato is where statues of Buddha were enshrined, which is why many scholars referred to it as a temple. However, this study proposes that Pato shall be referred to as a temple-style pagoda in a form unique to Myanmar, based on the origin of Pato, definition of pagodas, and Sarira Enrichment Record of Pato. Moreover, it seems more appropriate to name this type of structure Stupa Temple(塔殿) or Stupa Shrine(塔堂) rather than a Buddhist temple(佛殿) or Buddhist shrine(佛堂) for clear distinction. Pato, or temple-style pagodas, has a ${\acute{S}}ikhara-style$ structure at the center like Ananda Pato upon entering the Pagan (Bagan) kingdom period, on which Zedi-style structures are built. As a result of examining the integration of various Buddhist schools and religions focused on Theravada during the period of King Anawrahta and King Kyanzittha, the ${\acute{S}}ikhara-style$ structure is a symbolic representation of the fact that Theravada embraced Hinduism. The common features shared by pagodas in Myanmar are the centrality of place and the verticality of $y{\check{a}}ngti{\bar{a}}n$ (looking up to the sky) in terms of shape. All temples are placed at the most important and central space, and their forms represent strong religious $y{\check{a}}ngti{\bar{a}}n$ and verticality. These are the features that stand out most among various pagodas in Buddhist countries.

An Assumed Strain Beam Element for Spatial Post-Buckling Analysis of Non-symmetric and Shear Flexible Thin-Walled Beams (박벽보의 3차원 후좌굴 해석을 위한 Locking-Free 보요소)

  • Lee, Kyoung-Chan;Kim, Moon-Young;Park, Jung-Il;Chang, Sung-Pil
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.20 no.6
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    • pp.719-730
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    • 2007
  • This study presents a thin-walled space frame element based on the classical Timoshenko beam theory. The element is derived according to the assumed strain field in order to resolve the shear-locking phenomenon. The shape function is developed in accordance with the strain field which is assumed to be constant at a 2-noded straight frame element. In this study, the geometrically nonlinear analysis applies the Corotational procedure in order to evaluate unbalanced loads. The bowing effect is also considered faithfully. Two numerical examples are given; monosymmetric curved and nonsymmetric straight cantilever. When these example structures behave lateral-torsional bucking, the critical loads are obtained by this study and ABAQUS shell elements. Also, the post-buckling behavior is examined. The results give good agreement between this study and ABAQUS shell.