• 천문학회보
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• 제46권2호
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• pp.80.3-81
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• 2021

RR Lyrae variables are excellent distance indicators thanks to their visual magnitude-metallicity relation and well-defined Period-Luminosity Relations (PLRs) at infrared wavelengths. These population II variables together with the tip of the red giant branch provide primary calibration for the first-rung of the population II distance ladder. We will present new empirical calibration of RR Lyrae PLRs at near-infrared wavelengths using our data from the ongoing CFHT-WIRCam RR Lyrae program. We will discuss the systematic uncertainties involved in the calibration of these relations based on the latest Gaia EDR3 parallaxes and the implication for the cosmic distance scale.

• 한국환경복원기술학회지
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• 제3권3호
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• pp.29-36
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• 2000

The purpose of this study is to develop and adapt indicators for the rural community assessment. Bearing in mind, indicators are derived from the various theoretical literature review and the efficiency of the indicators has been tested through comparing and evaluating 3 different rural communities which was selected based on their distance from Seoul. In order to assess a rural development project, the assessment indicators should include at least 5 domains of natural environment, socio-economic, quality of living environment, community characteristics, public participation, which are the basic formation of indicators of this study. Furthermore, this approach could be a ground for the environmentally friendly rural development planning.

• 천문학회지
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• 제29권spc1호
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• pp.89-91
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• 1996

Within the next few years eclipsing binaries should yield primary distance measurements for the Magellanic Clouds as well as provide tests of theoretical low-metallicity stellar models.

• 천문학회지
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• 제29권spc1호
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• pp.65-66
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• 1996

• 천문학회보
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• 제21권
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• pp.22.2-22.2
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• 1996

• 한국농촌건축학회논문집
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• 제8권1호
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• pp.62-69
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• 2006

This study is based on the ecological design method related with the Building Landscape in Coastal Area, basically Building Landscape design theories are affected the visual distance and visual area. The results derived of this study are as follows. First, We established design method of Building Landscape in Coastal Area in consideration of Ecological Environment that is purposed by means of the Normative theory study analysis and contents analysis related with Landscape and Architecture planning theory. Second, We can define 'Micro Landscape', 'Urban Landscape', and 'Wide Landscape'. 'Micro Landscape' are 'Near view'. 'Urban Landscape' are related 'Middle-distance view' and 'Long-distance view'. 'Wide Landscape' are related 'High & Long-distance view'. Third, We can also define 'Ecological Mode', 'Formal Aesthetic Mode', 'Psychological Mode', and 'Semiotical Mode' by the dimensions of macro scale. finally, we define 48 detailed factors types of 3 visual Area of Building Landscape in Coastal Area by the dimensions of micro scale.

• Spatial Information Research
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• 제23권3호
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• pp.23-33
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• 2015

현재 계획단계에서 구득하여 활용할 수 있는 토지이용 관련 정보는 시도, 시군구, 그리고 읍면동과 같은 집계된 단위의 자료가 주를 이루고 있어, 미시적 공간단위에서의 변화 양상을 파악하기에는 근본적인 한계가 존재한다. 본 연구의 목적은 존 내 물리적 도시특성지표를 바탕으로 공간 개발패턴을 추정하는 방법론을 개발하는데 있다. 본 연구에서는 강남지역을 육각형 픽셀로 분할하고 각 공간분석단위별로 판매 및 업무의 건축물 개발강도를 단계별로 구분하여 도시의 공간적 특성이 판매 및 업무에 어떠한 영향을 미치는가를 다항 로지스틱 회귀분석을 통해 수행하였다. 분석결과 도로와 버스정류장과의 거리가 증가하면 밀도 개발 확률이 감소하며, 수계와의 거리가 증가하면 밀도 개발 확률이 높아짐을 확인하였다. 본 연구의 방법론과 결과물은 도시계획분야에서 집계된 자료를 미시적 공간으로 세분하는 방법론으로 활용될 것으로 판단된다.

• 천문학회지
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• 제30권1호
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• pp.27-70
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• 1997

The brightest stars in galaxies have been used as distance indicators since Hubble. However, the accuracy of the brightest stars for distance estimates has been controversial. Recently, Rozanski & Rowan-Robinson [1994 : MNRAS, 271, 530] argued large errors of this method for the distance determination : 0.58 mag and 0.90 mag, respectively, for the brightest red stars and the brightest blue stars, while Karachentsev & Tikhonov [1994 : A&A, 286, 718] suggested much smaller errors in the distance determination than the former: 0.37 mag for the brightest red stars and 0.46 mag for the brightest blue stars. The reasons for these conflicting results are not yet known. In this study we have investigated the accuracy of this method using a sample of 17 galaxies for which Cepheid distances are known and reliable photometry of the brightest stars are available. We have obtained the calibrations of the relations between the mean luminosities of the three blue and red brightest supergiants (BSGs and RSGs, respectively) and the total luminosities of the parent galaxies: $= 0.21M_B^T- 3.84, \sigma(M_v) = 0.37 mag,\;and\;\delta_{\mu0}=0.47$ mag for the brightest red supergiants, and $= 0.30M_B^T -3.02, \sigma(M_B)\;=\;0.55 mag,\;and\; \delta_{\mu0}=0.79mag$ for the brightest blue supergiants. Also it is found that the errors in the distance determination are reduced by a factor of two, as the observing wavelengths increase from B-band to K-band. In conclusion, the brightest red supergiants are considered to be useful for determining the distances to resolved late-type galaxies.

• 한국실내디자인학회논문집
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• 제25권4호
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• pp.147-155
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• 2016

In order to ensure a certain level of the quality of design, standardized evaluation indicators are being used as an objective criterion. Even though the evaluation indicators are quantifiable, limitations such as inefficiency and inconsistency caused by manual task in the evaluation process still have been found. BIM (Building Information Modeling) technology that is commonly adopted in architectural design process provides an environment which enables us to figure out a building model to be interpreted quantitatively with the basis of the building information model. It supports quantitative, consistent, accurate and quick evaluations so as to improve quality of design even in the initial design phase. This paper aims to establish BIM-enabled quantitative indicators and an evaluation framework to analyze building circulation even in early phase of design. The indicators are composed of 4 types (relative distance, accessibility, simplicity, pedestrian friendliness) and 7 sub-types. The evaluation framework is the process to derive Parameterized Path Value (PPV) as weighting on each indicator. For demonstrating the scalability of the suggested evaluation indicators and the framework, the authors implemented an evaluation tool and a case study has been carried out by using an actual building remodel project.

• 천문학회보
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• 제45권1호
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• pp.31.3-32
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• 2020

The surface brightness fluctuation (SBF) is one of the most crucial distance indicators for unresolved stellar systems at large distances. Here, we present an evolutionary population synthesis model of the surface brightness fluctuation (SBF) for normal and He-enriched simple stellar populations (SSPs). Our SBF model for the normal-He population agrees well with other existing models, but the He-rich populations bring about a substantial change in the SBF of SSPs. Our normal-He SBF model well reproduces the observed SBFs of the Milky Way globular clusters, but the SBFs of early-type galaxies in the Virgo Cluster are placed between the normal-He and He-rich SBF models. We show that the SBF-based distance estimation would be affected by up to a 10-20% level in I- and near-IR bands at given colors. Finally, we propose that when combined with independent metallicity and age indicators such as Mg2 and H��, the UV and optical SBFs can readily detect underlying He-rich populations in unresolved stellar systems. Given the degree of the SBF variation resulting from the population difference, we suggest that the distance measurement before the proper in-depth analysis of stellar populations should be done with great caution.