• Title/Summary/Keyword: Scale-space

Search Result 2,522, Processing Time 0.036 seconds

Disturbance in the Daytime Midlatitude Upper F Region Associated with a Medium Scale Electrodynamic Vortex Motion of Plasma

  • Hegai, Valery V.;Kim, Vitaly P.
    • Journal of Astronomy and Space Sciences
    • /
    • v.33 no.3
    • /
    • pp.207-210
    • /
    • 2016
  • Under the assumption of the presence of a medium-scale E × B drift vortex of plasma in the daytime midlatitude F region, and using a simplified ionospheric model, we demonstrate that the E × B drift produces noticeable perturbations in the horizontal distribution of the plasma density in the upper F region. The pattern of ion density perturbations shows two separate medium scale domains of enhanced and reduced ion density with respect to the background. The E × B drift does not produce multiple small-scale ion density irregularities through plasma mixing because of the suppression effect of the field-aligned ambipolar plasma diffusion.

High Performance Hybrid Direct-Iterative Solution Method for Large Scale Structural Analysis Problems

  • Kim, Min-Ki;Kim, Seung-Jo
    • International Journal of Aeronautical and Space Sciences
    • /
    • v.9 no.2
    • /
    • pp.79-86
    • /
    • 2008
  • High performance direct-iterative hybrid linear solver for large scale finite element problem is developed. Direct solution method is robust but difficult to parallelize, whereas iterative solution method is opposite for direct method. Therefore, combining two solution methods is desired to get both high performance parallel efficiency and numerical robustness for large scale structural analysis problems. Hybrid method mentioned in this paper is based on FETI-DP (Finite Element Tearing and Interconnecting-Dual Primal method) which has good parallel scalability and efficiency. It is suitable for fourth and second order finite element elliptic problems including structural analysis problems. We are using the hybrid concept of theses two solution method categories, combining the multifrontal solver into FETI-DP based iterative solver. Hybrid solver is implemented for our general structural analysis code, IPSAP.

Hue Preserved Multi-scale Retinex to Improve Color Reproduction

  • Kyung, Wang-Jun;Lee, Tae-Hyung;Lee, Cheol-Hee;Ha, Yeong-Ho
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2009.10a
    • /
    • pp.1546-1549
    • /
    • 2009
  • In recent studies on tone reproduction with the objective of reproducing natural looking colors in digital images, an integrated multi-scale retinex (IMSR) has produced great naturalness in the resulting images. Most methods, including IMSR, work in RGB or quasi-RGB color spaces. As such, this produces hue distortion from the perspective of the human visual system. Accordingly, this paper proposes the hue preserved multi-scale Retinex (HPMSR) method to obtain a high contrast and naturalness. The proposed method enhanced the $L^*$ and saturation values in CIELAB color space. As a result, the visibility in dark shadows in the resulting images was improved.

  • PDF

An Estimating Space Program of Technical High School for Future Educational Curriculum (전문교과 교육과정에 대응하기 위한 공업계고등학교 공간규모 산정에 관한 연구)

  • Lee, Sang-Min
    • The Journal of Sustainable Design and Educational Environment Research
    • /
    • v.7 no.2
    • /
    • pp.12-29
    • /
    • 2008
  • The problem should be approached in terms of recovering essential functions of technical high school and identification to supply stable and quality human resources in technical sector. An adequate space programming for technical high school is needed to educate effective skills and techniques. Considering the education directions of vocational high school, the article covers principals of technical school's construction plan and directions and, based on this, suggest the way of estimating the scale in construction plan of technical school. Through this research, systematic and reasonable space planning can be possible. The range of this research is based on development directions of society and education and an objective standard in a newly reformed the 7th Stage of Education. In addition, the research is limited to technical high school among kinds of vocational high school. The purpose is to redefine the role of technical school that face identification crisis currently, comparing to the past, and to suggest a more effective space planning. The research limits the space to classes for specialized subjects, a core space for education in technical school among diverse spaces.

  • PDF

A Study on The Modulor System Shown in Structure and Envelope of Le Corbusier's Works (Le Corbusier 건축의 구조와 외피에 나타나는 모듈러 시스템에 관한 연구)

  • Cho, Sung-Hyun
    • Journal of The Korean Digital Architecture Interior Association
    • /
    • v.10 no.1
    • /
    • pp.15-22
    • /
    • 2010
  • As for structural system, which constitutes his construction, there are column inside dimension and span which constitutes plane, and as for constructions for section, there are C.H and slab, and as for constructive factors for envelope, there are window and closing panel of outer wall, and as for opening, there are punching window and wave window. With these constructive parts and opening of envelope, his construction composes volume and mass. The relation of structure and modulor which are shown in his later construction can be divided in two cases that modulor is directly and indirectly adapted for rate and measure calculation of the constructive body. As for indirectly adapted case, we can find it form most of his later construction, it is living place in which human beings life is, and it is adapted mainly for small space. In his construction, he tried to tell human scale and sense of musical rhythm through modulor. In other words, he played sense of space and musical scale by adapting regular and repetitive modulor of opening, and in small space for daily life, he made the size of space into the space which human can perceive. And, if we interpret mudulor in modern meaning, it is an establishment of radius of human act. And, we can make organic and harmonic design of space if we use modulor as origin of human centered measurement calculation, and if we adapt space after dividing by use.

GENERALIZED ANALYTIC FEYNMAN INTEGRAL VIA FUNCTION SPACE INTEGRAL OF BOUNDED CYLINDER FUNCTIONALS

  • Chang, Seung-Jun;Choi, Jae-Gil;Chung, Hyun-Soo
    • Bulletin of the Korean Mathematical Society
    • /
    • v.48 no.3
    • /
    • pp.475-489
    • /
    • 2011
  • In this paper, we use a generalized Brownian motion to define a generalized analytic Feynman integral. We then obtain some results for the generalized analytic Feynman integral of bounded cylinder functionals of the form F(x) = $\hat{v}$(($g_1,x)^{\sim}$,..., $(g_n,x)^{\sim}$) defined on a very general function space $C_{a,b}$[0,T]. We also present a change of scale formula for function space integrals of such cylinder functionals.

VERTICAL DENSITY DISTRIBUTION OF THE GALAXY FROM STAR COUNT ANALYSIS

  • Sohn, Young-Jong
    • Journal of Astronomy and Space Sciences
    • /
    • v.19 no.1
    • /
    • pp.19-24
    • /
    • 2002
  • The five space density distribution D(z) wish distance perpendicular to the Galactic plane were combined. The scale heights and the local densities at z = 0 of the thin disk, thick disk, and the halo components were estimated from the nonlinear least square fits of exponential law. The scale heights of the thin disk, thick disk, and the halo components were estimated to be $260{\pm}90$ pc, $660{\pm}220$ pc, and $3.6{\pm}1.4$ kpc, respectively. The density ratio of each components to the thin disk component at the galactic plane, i.e., z = 0.0, were also derived as 1 :0.07:0.002. Our model fit suggests that the thick disk component has a local density of 6.9% relative to the thin disk.

Redshift Space Distortion on the Small Scale Clustering of Structure

  • Park, Hyunbae;Sabiu, Cristiano;Li, Xiao-dong;Park, Changbom;Kim, Juhan
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.42 no.2
    • /
    • pp.78.3-78.3
    • /
    • 2017
  • The positions of galaxies in comoving Cartesian space varies under different cosmological parameter choices, inducing a redshift-dependent scaling in the galaxy distribution. The shape of the two-point correlation of galaxies exhibits a significant redshift evolution when the galaxy sample is analyzed under a cosmology differing from the true, simulated one. In our previous works, we can made use of this geometrical distortion to constrain the values of cosmological parameters governing the expansion history of the universe. This current work is a continuation of our previous works as a strategy to constrain cosmological parameters using redshift-invariant physical quantities. We now aim to understand the redshift evolution of the full shape of the small scale, anisotropic galaxy clustering and give a firmer theoretical footing to our previous works.

  • PDF

Use of Importance-Performance Analysis to Evaluate Open Space Environment functions in Taejon City (중요도(重要度)-성취도(成就度) 분석(分析)에 의한 대전시(大田市) 녹지환경(綠地環境) 기능(機能) 평가(評價))

  • Song, Hyung Sop
    • Korean Journal of Agricultural Science
    • /
    • v.21 no.2
    • /
    • pp.92-102
    • /
    • 1994
  • This study examined Public Evaluation for functions of urban open space environment using a marketing strategy called Importance-Performance analysis. 12 main function attributes for urban open space environment were selected 150 respondents were sampled in Taejon city by personal interview. Ratings used mean values from a seven-point scale. Results were then graphically displayed on an easily interpreted two-dimensional 'Action Grid'. Generally Importance Ratings were high, but Performance Ratings were low relatively for various open space environment functions. In air pollution control function the difference was the most large. The results of rating scale analysis indicated repondents' sexual and residence period difference.

  • PDF

Optical Long-slit Spectroscopy of Parsec-scale Jets

  • Oh, Heeyoung;Pyo, Tae-Soo;Yuk, In-Soo;Kim, Kang-Min;Lee, Sungho;Park, Byeong-Gon
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.38 no.1
    • /
    • pp.55.2-55.2
    • /
    • 2013
  • We present the observational study of parsec-scale jets from YSOs reaching lengths of several arc-minutes. The medium-resolution spectroscopic data were obtained between 6000 - $7000{\AA}$ with BOAO long-slit spectrograph. By performing multi-position observation, we investigated the physical variation of the jets and the ambient gas along the whole path of the jets. The flux, electron density, ionization fraction, and electron temperature are discussed with the estimated line ratios between from [OI], [NII], $H{\alpha}$ and [SII] emission lines. This study carried out with more than 8 jets of YSOs including low- to intermediate-mass stars. We also briefly discuss the kinematics of the outflows using spatial and spectroscopic data.

  • PDF