• The Bulletin of The Korean Astronomical Society
• /
• v.38 no.2
• /
• pp.41.1-41.1
• /
• 2013

To test whether the close relationships between host and satellite galaxies in isolated groups are also found in the harsh environment of a galaxy cluster, we carry out a case study of WHL 085910.0+294957, a galaxy cluster at z=0.30, using deep images obtained with the 2.1-m Otto Struve telescope and CQUEAN CCD camera. When environmental parameters are controlled, the local weighted mean color of faint galaxies shows a measurable correlation with the color of their bright ($M_i$ < -18) neighbor. The most striking result is that the red (r - i > 0.2) and bright galaxies within 200 kpc distance from the center of the cluster are correlated in color with very faint ($M_i$ > -14) galaxies around them by $(r-i)_{satellites}=(7.276{\pm}1.402){\times}(r-i)_{host}-2.434$ (correlation coefficient = 0.665). We suggest three scenarios to interpret the results: vestiges of infallen groups, dwarf capturing, and tidal tearing of bright galaxies.

• The Bulletin of The Korean Astronomical Society
• /
• v.39 no.2
• /
• pp.52-52
• /
• 2014

It is widely accepted that the evolution of galaxies is accelerated in dense environments. According to recent studies, however, the evolution by direct interactions between galaxies is known to be most active in a galaxy group rather than in a galaxy cluster. In particular, the central galaxy in a group is closely related to its satellites in the properties such as morphology, color and star formation rate, because those galaxies evolve together in a small-scale environment. Currently, however, it is not yet studied well whether such conformity between bright galaxies and their faint companions remains after a galaxy group falls into a galaxy cluster. Recently, Lee et al. (2014) have found that the colors of bright galaxies show a measurable correlation with the mean colors of faint companions around them in WHL J085910.0+294957, a galaxy cluster at z = 0.3, which may be the vestige of infallen groups in the cluster. As a follow-up study, we study Abell 2744, an ongoing cluster-cluster merger at z = 0.308, using the HST Frontier Fields Survey data. The cluster members are selected based on the distributions of color, size and concentration along magnitude. The correlation in color between bright galaxies and their companions is not found in the full area of Abell 2744. However, when the area is limited to the southeastern part of the Abell 2744 image, the mean color of faint companions shows marginal dependence (> $2{\sigma}$ to Bootstrap uncertainties) on the color of their adjacent bright galaxy. We discuss the implication of these results, focusing on their dependence on local environments.

• The Bulletin of The Korean Astronomical Society
• /
• v.39 no.1
• /
• pp.35.2-35.2
• /
• 2014

Today, it is widely accepted that dense environments tend to accelerate galaxy evolution. However, according to recent studies, the environments where galaxies evolve most considerably are galaxy groups rather than galaxy clusters. In an isolated group, the central host galaxy and its satellites co-evolve and interact with each other; as a result, they tend to have similar properties. Such conformity between host and satellite galaxies are relatively well known in galaxy groups, but it is hardly studied what happens after such galaxy groups merge into a galaxy cluster. Recently, J. H. Lee et al. (2014) have found that the colors of bright galaxies in WHL J085910.0+294957, a galaxy cluster at z = 0.3, show a measurable correlation with the mean colors of faint companions around them, which may be the vestige of infallen groups in the cluster. As a follow-up study, we explore more galaxy clusters, Abell 3659 and Abell 1146 at z ~ 0.1, using deep images obtained from the Magellan (Baade) 6.5-m telescope. Cluster members are selected based on the distributions of color, size and concentration along magnitude and spatial distribution. We investigate the dependence of the mean colors of faint companion galaxies on local environments and the properties of adjacent bright galaxies. After comparing the results with those in J. H. Lee et al. (2014), we discuss the origin of the relationships between bright galaxies and their faint companions based on their dependence on cluster properties.

• Communications of the Korean Mathematical Society
• /
• v.24 no.3
• /
• pp.367-379
• /
• 2009

For a prime number p, let $\mathbb{Q}_p$ denote the p-adic field and let $\mathbb{Q}_p^d$ denote a vector space over $\mathbb{Q}_p$ which consists of all d-tuples of $\mathbb{Q}_p$. For a function f ${\in}L_{loc}^1(\mathbb{Q}_p^d)$, we define the Hardy-Littlewood maximal function of f on $\mathbb{Q}_p^d$ by $$M_pf(x)=sup\frac{1}{\gamma{\in}\mathbb{Z}|B_{\gamma}(x)|H}{\int}_{B\gamma(x)}|f(y)|dy$$, where |E|$_H$ denotes the Haar measure of a measurable subset E of $\mathbb{Q}_p^d$ and $B_\gamma(x)$ denotes the p-adic ball with center x ${\in}\;\mathbb{Q}_p^d$ and radius $p^\gamma$. If 1 < q $\leq\;\infty$, then we prove that $M_p$ is a bounded operator of $L^q(\mathbb{Q}_p^d)$ into $L^q(\mathbb{Q}_p^d)$; moreover, $M_p$ is of weak type (1, 1) on $L^1(\mathbb{Q}_p^d)$, that is to say, |{$x{\in}\mathbb{Q}_p^d:|M_pf(x)|$>$\lambda$}|$_H{\leq}\frac{p^d}{\lambda}||f||_{L^1(\mathbb{Q}_p^d)},\;\lambda$ > 0 for any f ${\in}L^1(\mathbb{Q}_p^d)$.

• Journal of the Korean Society of Costume
• /
• v.52 no.1
• /
• pp.21-36
• /
• 2002

The Miaos have their own unique and luxurious culture traditional and modern formed as they have experienced repeated fusion into and resistance against the Han Race or the Chinese in their long and old history. Taijiang County of Guizhou Provice, in which whey have been living, is endowed with natural beauty. Thus their culture enjoys abundant and diverse contents of artificial and natural character. Naturally, their costume reflects cultural and natural features in abundance and variety. This dissertation aims to investigate the artistic character of Miaos' traditional costume as reflected in patterns for their embroidery. As for the artistic character of the patterns for embroidery, the following were found. To begin with, the space in the Miaos' embroidery is, unlike the measurable three-dimensional space found in Greek art, unmeasurable and fantastic with its beauty, majesty and peculiarity. It is as if immersed in limitless space, they were in communion with gods and universe. Another characteristic is the use of image construction beyond mere imitation. Their mode of image construction was realistic in that patterns as a whole reveal an abstract form or meaning but separately they portray visual representations of concrete thins in nature. Still another is that sense of motion conveyed by the basic curve line is full of life. It was the result of using light rhythm breaking stereotypic balance and symmetry. Finally, the colouring was abstract, and a strong contrast between black and white was gorgeous and fantastic.

• Journal of Magnetics
• /
• v.18 no.3
• /
• pp.308-310
• /
• 2013

Translation induced by the field-gradient force is being observed for a single ferromagnetic iron grain and a ferrimagnetic grain of a ferrite sample ($CuFe_2O_4$). From measurements on the translation, precise saturated magnetization of $M_S$ is possible for a single grain. The method is based on the energy conservation rule assumed for the grain during its translation and the grain is translated through a diffuse area under microgravity conditions. The results of the two materials indicate that a field-induced translation of grain bearing spontaneous moment is generally determined by a field-induced potential $-mM_SH(x)$ where m denotes the mass of sample. According to the above translations, the detection of $M_S$ is not interfered by any signals from the sample holder. The $M_S$ measurement does not require m value. By observing translations resulting from fieldinduced volume forces, the magnetization of a single grain is measurable irrespective of its size; the principle is also applicable to measuring susceptibility of diamagnetic and paramagnetic materials.

• Journal of The Korean Astronomical Society
• /
• v.54 no.6
• /
• pp.171-182
• /
• 2021

The lack of short baselines, referred to as the short-spacing problem (SSP), is a well-known limitation of the performance of radio interferometers, causing a reduction of the flux detected from source structure on large angular scales. The very large number of antennas operated in the Atacama Large Millimeter/sub-millimeter Array (ALMA) generates situations for which the impact of the SSP takes a complex form, not simply measurable by a single number, such as the maximal recoverable scale. In particular, extended antenna configurations, complemented by a small group of closeby antennas at the centre of the array, may result in a double-humped baseline distribution with a significant gap between the two groups. In such cases one should adopt as the effective maximal recoverable scale the one associated with the extended array and use only the central array to recover missing flux, as one would do with single dish or ACA (Atacama Compact Array) observations. The impact of the missing baselines can be very important and may easily be underestimated, or even overlooked. The present study uses ALMA archival data of the ²⁹SiO(8-7) line emission of the AGB star W Hydrae for a demonstration. A critical discussion of the reliability of the observations away from the star is presented together with comments of a broader scope. Properties of the circumstellar envelope of W Hya within ~15 au from the star, many of which are not mentioned in the published literature, are briefly described and compared with R Doradus, an AGB star having properties very similar to W Hya.

• Korean Institute of Interior Design Journal
• /
• v.26 no.5
• /
• pp.125-134
• /
• 2017

This study is aimed at analyzing desired spaces and demands for their improvements, and subsequently proposing the design plan for eating and drinking places for solo diners by surveying the user satisfaction based on the analysis of the space configuration, and the physical environment of eating and drinking spaces for solo diners. Theoretical discussions about eating and drinking spaces for solo diners and their physical environment were reviewed from the previous studies, and an on-site survey was conducted with a checklist, for which the items regarding configuring elements of physical environments for the satisfaction with eating and drinking spaces for solo diners have been derived. Measurable checklist items according to the configuration of eating and drinking spaces were derived for this survey, which had then been conducted with diners in the eating and drinking spaces for 2 weeks. The analysis results are as follows. First, cleanliness is required as a necessity for the user satisfaction in eating and drinking spaces for solo diners. Second, a '-' shaped bar and the spaces to utilize and combine additional facilities are required in the central service space. Third, the self service should be performed in the additional service space. Fourth, the menu composition and the location selection considering main age groups of diners are needed. Fifth, interior design elements need to be improved to allow diners to feel visual interest along with enjoying food and beverage. It is considered that the strategies of spatial design need to be analyzed and proposed from the perspective of design among the physical environments of eating and drinking spaces for solo diners in future studies.

• Proceeding of Spring/Autumn Annual Conference of KHA
• /
• 2004.11a
• /
• pp.335-341
• /
• 2004

According to the improvements of the education and the cultural level, the noise pollutions which have been occupying a major portion of civil petitions about environment is gradually aggravating. Especially, the plumbing noises which took place at machine room of dormitory are the compositive shapes of an air-borne sounds and a solid-borne sounds. So it has been causing to injure the comfortable residential environment of residents that it is propagated in a residential space. Judging from this point of view, this study grasped the propagation and the properties of attenuation about four varieties's plumbing noise which took place at machine room to understand that it cause influences to a residential space. In this point, we understand the peculiar features by measuring noise, which was generated from equipment in machine rooms of three dormitories having different features. On the basis of these features, we examine all predictability and reliability in comparing the predictive value with the measurable one, using architectural acoustic simulation.

• Journal of the Chungcheong Mathematical Society
• /
• v.8 no.1
• /
• pp.161-166
• /
• 1995

Let (${\Omega}$, ${\Sigma}$, ${\mu}$) be a finite perfect measure space, and let $f:{\Omega}{\rightarrow}X$ be strongly measurable. f is Pettis integrable if and only if there is a sequence ($f_n$) of Pettis integrable functions from ${\Omega}$ into X such that (a) there is a positive increasing function ${\phi}$ defined on [0, ${\infty}$) such that ${\lim}_{t{\rightarrow}{\infty}}\frac{{\phi}(t)}{t}={\infty}$ and sup $f_{\Omega}{\phi}({\mid}x^*f_n{\mid})d{\mu}$ < ${\infty}$ for each $x^*{\in}B_{X*}$,$n{\in}N$, and (b) for each $x^*{\in}X^*$, $lim_{n{\rightarrow}{\infty}}x^*f_n=x^*fa.e.$.