• Title/Summary/Keyword: Consistent measure

Search Result 386, Processing Time 0.024 seconds

Merging Galaxy Cluster Abell 115: Weak Lensing with Subaru Observation

  • Kim, Mincheol;Jee, Myungkook J.
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.42 no.2
    • /
    • pp.41.1-41.1
    • /
    • 2017
  • We present weak-lensing analysis of the merging galaxy cluster Abell 115 at z=0.197 based on Subaru i and V band images. As merging clusters often show, Abell 115's merging signatures include radio relics, double X-ray peaks, and large offsets between the cluster member galaxies and the X-ray distributions. A weak-lensing study provides underlying dark matter distribution, the key information to determine the complex merging scenario of the cluster. In this work, we present 2D mass reconstruction of the cluster, which reveals two distinct mass peaks consistent with galaxy distributions. We measure the first weak-lensing mass of each subcluster. Our weak-lensing total mass estimate is a few factors lower than the published dynamical mass obtained from velocity dispersion. This large mass discrepancy may be attributed to a significant departure from dynamical equilibrium. We also re-analyze the archival chandra data and find that the result is consistent with weak-lensing mass.

  • PDF

Nondestructive Characterization of Materials Using Laser-Generated Ultrasound

  • Park, Sang-Woo;Lee, Joon-Hyun
    • International Journal of Reliability and Applications
    • /
    • v.5 no.1
    • /
    • pp.1-13
    • /
    • 2004
  • It is recently well recognized that the technique for the one-sided stress wave velocity measurement in structural materials provides measurement in structural materials provides valuable information on the state of the material such as quality, uniformity, location of cracked or damaged area. This technique is especially effective to measure velocities of longitudinal and Rayleigh waves when access to only one surface of structure is possible. However, one of problems for one-sided stress wave velocity measurement is to get consistent and reliable source for the generation of elastic wave. In this study, the laser based surface elastic wave was used to provide consistent and reliable source for the generation of elastic wave into the materials. The velocities of creeping wave and Rayleigh wave in materials were measured by the one-sided technique using laser based surface elastic wave. These wave velocities were compared with bulk wave velocities such as longitudinal wave and shear wave velocities to certify accuracy of measurement. In addition, the mechanical properties such as poisson's ratio and specific modulus(E/p) were calculated with the velocities of surface elastic waves.

  • PDF

Messier 3: An Extra-Galactic System with Two Globular Clusters

  • Lee, Jae-Woo;Sneden, Christopher
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.46 no.1
    • /
    • pp.34.3-34.3
    • /
    • 2021
  • We present Ca-CN-CH-NH photometry for the globular cluster (GC) M3. Our new photometric system combined with robust and self-consistent theoretical fine model grids allows us to measure key elements in stellar populations, [Fe/H], [C/Fe], and [N/Fe], even in the extremely crowded fields. Our results show that M3 consists of two GCs with different chemical abundances, structural and kinematical properties. Furthermore, each GC has its own carbon-nitrogen anticorrelation with whose fractions of the CN-weak populations are consistent with those in the Magellanic Clouds. We suggest that M3 is a merger remnant of two GCs, most likely in a dwarf galaxy environment and accreted to our Milky Way Galaxy later in time.

  • PDF

Aerial scene matching using linear features (선형특징을 사용한 항공영상의 정합)

  • 정재훈;박영태
    • Proceedings of the IEEK Conference
    • /
    • 1998.06a
    • /
    • pp.689-692
    • /
    • 1998
  • Matching two images is an essential step for many computer vision applications. A new approach to the scale and rotation invariant scene matching is presented. A set of andidate parameters are hypthesized by mapping the angular difference and a new distance measure to the hough space and by detecting maximally consistent points. The proposed method is shown to be much faster than the conventinal one where the relaxation process is repeated until convergence, while providing robust matching performance, without a priori information on the geometrical transformation parameters.

  • PDF

Development of the Wind Power Forecasting System, KIER Forecaster (풍력발전 예보시스템 KIER Forecaster의 개발)

  • Kim Hyun-Goo;Lee Yung-Seop;Jang Mun-Seok;Kyong Nam-Ho
    • New & Renewable Energy
    • /
    • v.2 no.2 s.6
    • /
    • pp.37-43
    • /
    • 2006
  • In this paper, the first forecasting system of wind power generation, KIER Forecaster is presented. KIER Forecaster has been constructed based on statistical models and was trained with wind speed data observed at Gosan Weather Station nearby Walryong Site. Due to short period of measurements at Walryong Site for training the model, Gosan wind data were substituted and transplanted to Walryong Site by using Measure-Correlate-Predict(MCP) technique. The results of One to Three-hour advanced forecasting models are consistent with the measurement at Walryong site. In particular, the multiple regression model by classification of wind speed pattern, which has been developed in this work, shows the best performance comparing with neural network and auto-regressive models.

  • PDF

A Study of Body Surface Area Calculation -Centering around 40 Ages- (체표면적 산출식에 관한 연구 -40대 여성을 중심으로-)

  • Im, Soon
    • The Research Journal of the Costume Culture
    • /
    • v.2 no.2
    • /
    • pp.385-394
    • /
    • 1994
  • Data of the body surface is a necessary unit for the measuring of metabolism energy and activity energy. And also, these data are referring to check the degree of retaining warmth of clothes, to find the effect of heat insulation according to body surface, to calculate an average temperature of skin, and to study the several fields of clothing. In measuring of body surface, it si actually impossible to measure a subject's body surface in each experiment. As the experimental method, both gypsum method, by which the shape of body an be copied as it is, and the weighting method from which planed body surface area can be measured with consistent thickness of polyprophylene film as used. In fact, every female subject feels uncomfortable to measure her body surface as a naked body. There, it is providing a simple, accurate regressive equation with weight & height as variable factors in this study. This equation is as=117.02W+77.31H-3344.94 with average error : 0.1%, absolute average error : 2.07%.

  • PDF

Conductance of a Single Molecule Junction Formed with Ni, Au, and Ag Electrodes

  • Kim, Taekyeong
    • Journal of the Korean Chemical Society
    • /
    • v.58 no.6
    • /
    • pp.513-516
    • /
    • 2014
  • We measure the conductance of a 4,4'-diaminobiphenyl formed with Ni electrodes using a scanning tunneling microscope-based break-junction technique. For comparison, we use Au or Ag electrodes to form a metal-molecular junction. For molecules that conduct through the highest occupied molecular orbital, junctions formed with Ni show similar conductance as Au and are more conductive than those formed with Ag, consistent with the higher work function for Ni or Au. Furthermore, we observe that the measured molecular junction length that is formed with the Ni or Au electrodes was shorter than that formed with the Ag electrodes. These observations are attributed to a larger gap distance of the Ni or Au electrodes compared to that of the Ag electrodes after the metal contact ruptures. Since our work allows us to measure the conductance of a molecule formed with various electrodes, it should be relevant to molecular electronics with versatile materials.

A Study On The Relationship Between Ownership Structure And Corporate Social Responsibility (기업 소유구조와 사회적 책임투자간 관계에 대한 실증 분석)

  • Park, Yong-Sam;Pyo, Se-Won
    • Korean Management Science Review
    • /
    • v.25 no.3
    • /
    • pp.123-133
    • /
    • 2008
  • We investigate the relationship between ownership structure and firm performance. For this paper, we use the 'donation' figure from the income statement of each firm as a measure of firm Performance lather than short-term financial measure that has been wifely used by previous studies. Our results are consistent with the idea that family ownership is both prevalent and substantial in Korea. More importantly, however, non-family firms are found to give more donations than family firms. This suggests that non-family firms more readily recognize the significance of corporate social responsibility and play an active role in philanthropy.

Scence Change Adaptive Bit Rate Control Using Local Variance (국부 분산을 이용한 장면 전환 적응 비트율 제어)

  • 이호영;김기석;박영식;송근원;남재열;하영호
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.22 no.4
    • /
    • pp.675-684
    • /
    • 1997
  • The bit rate control algorithm which is capable of handing scene change is proposed. In MPEG-2 TM5, block variance is used to measure block activity. But block variance is not consistent with human visual system and does not differenciate the distribution of pixel values within the block. In target bit allocation process of TM5, global complexity, obtained by results of previous coded pictures, is used. Since I pictures are spaced relatively far apart, their complexity estimate is not very accurate. In the proposed algorithm local variance is used to measure block activity and detect scene change. Local variance, using deviation from the mean of neighboring pixels, well represents the distribution of pixel values within the block. If scene change is detected, the local variance information is used for target bit allocation process. Allocating target bits for I picture, the average local variance difference between previous and current I picture is considered. The experimental results show that the proposed algorithm can detect scene change very precisely and gives better picture quality and higher PSNR values than MPEG-2 TM5.

  • PDF

Parallelism and Straightness Measurement of a Pair of Rails for Ultra Precision Guide-ways (초정밀 안내면 레일의 평행도 및 진직도 동시측정)

  • Hwang, Joo-Ho;Park, Chun-Hong;Wei, Gao;Kim, Seung-Woo
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.24 no.3 s.192
    • /
    • pp.117-123
    • /
    • 2007
  • This paper describes a three-probe system that can be used to measure the parallelism and straightness of a pair of rails simultaneously. The parallelism is measured using a modified reversal method, while the straightness is measured using a sequential two-point method. The measurement algorithms were analyzed numerically using a pair of functionally defined rails to validate the three-probe system. Tests were also performed on a pair of straightedge rails with a length of 250 mm and a maximum straightness deviation of $0.05{\mu}m$, as certified by the supplier. The experimental results demonstrated that the parallelism-measurement algorithm had a cancellation effect on the probe stage motion error. They also confirmed that the proposed system could measure the slope of a pair of rails about $0.06{\mu}rad$. Therefore, by combining this technique with a sequential differential method to measure the straightness of the rails simultaneously, the surface profiles could be determined accurately and eliminate the stage error. The measured straightness deviation of each straight edge was less than $0.05{\mu}m$, consistent with the certified value.