• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.2 no.2
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• pp.36-45
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• 2003

This paper presents a way to maximize transmission efficiency and reception ability through transmission diversity technology, which can be adapted to wireless multimedia OFDM (orthogonal FDM) system. The presented method gives a comparative analysis between a case where parameter a for time average is 0.3, i with consideration of channel presumption and two types of rms delayed proliferation, which is 50nsec, 150nsec, for the performance analysis of STTC (Space-Time Trellis Code) using time-space code method which is appropriate for MIMO channel, and performance, in the case, where presumed channel value from long training column section is applied to the according frame in a single frame. The result shows that BER brought SNR improvement of 1.0dB in $10^{-3}$ when a was 0.3 than using only the long training column, and shows an increasement of general performance improvement when the time average factor is used.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.41.1-41.1
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• 2020

Different molecular lines trace different physical environments (with various densities and temperatures) within molecular clouds (MCs). Therefore, multimolecular line observations are crucial to study the physical and chemical structures of MCs. We observed the Orion A and Ophiuchus clouds in six different molecular lines as a Taeduk Radio Astronomy Observatory Key Science Program (TRAO-KSP), "mapping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale" (TIMES; PI: Jeong-Eun Lee). Here, we investigate the characteristic relations between the observed lines by performing the Principal Component Analysis (PCA). We also investigate the correlation between the line intensity distributions and the physical parameters, such as the gas column density and dust temperature. Finally, we will discuss how the correlations among different chemical tracers vary with the star formation environments.

• Journal of Astronomy and Space Sciences
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• v.28 no.1
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• pp.13-16
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• 2011

The $CH_3OH$ $4_2-5_1$ E transition was observed toward the Sgr B2 region, including the Principal Cloud and its surroundings. This methanol transition shows an extended emission along the 2'N cloud, which is believed to be colliding with the Principal Cloud and may trigger the massive star formation in this cloud. This extended methanol emission may also suggest that the 2'N cloud is under shocks. We derive total methanol column density $N(CH_3OH)\;=\;2.9{\pm}0.3{\times}10^{14}\;cm^{-2}$ toward the peak position of the extended emission. The fractional abundance of methanol is about 10.9, relative to the estimated total $H_2$ abundance, which is similar to the methanol abundances in quiet gas phase.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.6
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• pp.447-454
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• 2017

A three-dimensional two-phase large eddy simulation(LES) has been conducted to investigate the breakup and atomization of liquid jets such as a diesel jet in parallel flow and water jet in cross flow. Gas-liquid two-phase flow was solved by a combined model of Eulerian for gas flow and Lagrangian for a liquid jet. Two stochastic breakup models were implemented to simulate the liquid column and droplet breakup process. The penetration depth and SMD(Sauter Mean Diameter) were analyzed, which was comparable with the experimental data.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.40.1-40.1
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• 2016

We present the far-ultraviolet fluorescent molecular hydrogen ($H_2$) emission map observed with FIMS/SPEAR for ~76% of the sky. The fluorescent $H_2$ emission is found to be saturated by strong dust extinction at the optically thick, Galactic plane region. However, the extinction-corrected intensity of fluorescent $H_2$ emission is found to have strong linear correlations with the well-known tracers of the cold interstellar medium, such as the E(B-V) color excess, neutral hydrogen column density N(HI), $H{\alpha}$ emission, and CO $J=1{\rightarrow}0$ emission. The all-sky molecular hydrogen column density map is also obtained using a photodissociation region model. We also derive the gas-to-dust ratio, hydrogen molecular fraction ($f_{H2}$), and $CO-to-H_2$ conversion factor ($X_{CO}$) of the diffuse interstellar medium. The gas-to-dust ratio is consistent with the standard value $5.8{\times}10^{21}atoms\;cm^{-2}mag^{-1}$, and the $X_{CO}$ tends to increase with E(B-V), but converges to the Galactic mean value $1.8{\times}10^{20}cm^{-2}K^{-1}km^{-1}s$ at optically thick regions with E(B-V)>2.0.

• Journal of the Korean Institute of Rural Architecture
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• v.12 no.3
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• pp.19-26
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• 2010

This study is aimed to look into the craftsmanship non-educated constructors in Korean-style secondary stations(Gong-So) of Naepo region which is located in the northwestern Chungcheongnam-do. Although the area was persecuted as one of three cradles of Korean Catholicism, Catholic activities flourished there. The 13 cases of Korean-style secondary stations were selected through a survey report list about modern cultural assets of Chungcheongnam-do published in december 2004. This study examined the methods of plan layout and framework of Gong-So to look into craftsmanship of non-educated constructors, the results are as follows; The methods of plan layout are divided into three types according to existence and arrangement of inner column(Nae-Ju); 'Layout with Nae-Ju' is considered as the primary form of Korean-style Gong-So with using regular Nae-Ju. 'Layout with the different position of the center between Nae-Ju and exterior column(Oe-Ju)' and 'layout without Nae-Ju' is appeared in Korean-style Gong-So which is important to assembly and alter function. The methods of framework are appeared variously according to different plan layout for securing worship space. The unusal beam(Chung-Ryang) is used to solve different spans of altar and narthex. When space was formed widely without Nae-Ju, diagonal members and M letter type rafters are used, they are influenced by the technique of western wooden roof truss.

• Communications of the Korean Mathematical Society
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• v.38 no.3
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• pp.821-835
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• 2023

Hankel operators and their variants have abundant applications in numerous fields. For a non-zero complex number r, the r-Hankel operators on a Hilbert space 𝓗 define a class of one such variant. This article introduces and explores some properties of two other variants of Hankel operators namely k^th-order (C, r)-Hankel operators and k^th-order (R, r)-Hankel operators (k ≥ 2) which are closely related to r-Hankel operators in such a way that a k^th-order (C, r)-Hankel matrix is formed from r^k-Hankel matrix on deleting every consecutive (k - 1) columns after the first column and a k^th-order (R, r^k)-Hankel matrix is formed from r-Hankel matrix if after the first column, every consecutive (k - 1) columns are deleted. For |r| ≠ 1, the characterizations for the boundedness of these operators are also completely investigated. Finally, an appropriate approach is also presented to extend these matrices to two-way infinite matrices.

• Journal of The Korean Digital Architecture Interior Association
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• v.10 no.1
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• pp.15-22
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• 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.

• Journal of architectural history
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• v.4 no.1
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• pp.71-78
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• 1995

This study aims 1) to estimate the form of living house of pre-urbanization of Inchon, and 2) to ensure originality of to be achieve urban plan and living space plan which is base on local character by 3) arranging changed character of living space through the urbanization sequence by invest of house in natural village at Pupyung. The character of arranging living space of house at Pupyung is placing Sarang-chae(husband's block of house) instead of making another Haenrang-chae (visitor's block of house) and Sarang-chae is attach importance to Man's living space but today, have disappearing the uses of Sarang-bang (husband's living space) because by Man lives An-bang(originally woman's space). The character of plan is arranging room in both side of Maru(wooden living floor) in spite of different structure, and the uses of plan or room is changing to fit to purpose of according to environment of living. Generally, the structure is made by natural stone and cubed column, and used smaller member cause by rare wood material.

• Bulletin of the Korean Space Science Society
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• 1993.10a
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• pp.15-15
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• 1993

Revised Yale Isochrone(Green et al, 1987)과 Lee의 HB simulation data(LEE '||'&'||' Demarque 1990)을 이용하여 Park이 만든 CMD simulation program(Park 1983).에 쌍성을 첨가하면 CMD에 어느 정도의 영향을 나타내게 되는가를 조사하였다. MS, SGB와 RGB는 큰 변화가 없었으나, HB에서는 많은 변화를 나타내었다. 193919 S02401193919 ^x We have observed the emission of HC3N J= 4-3, 5-4 10-9 and 12-11 transitions toward the Sgr B2 central region in an area of 150"XISO" with resolutions of16"-48". The intensities and central velocities of line profiles show significant variations with positions. In contrast to the in tensities of the low J-level transitions which gradually increase from the central source toward the outside region the HC3N emission of the high J-level transition become stronger toward the central radio continuum source MO5. Systematic chainge in the radial velocity of each line profile occurs along north-south direction there are a few peaks in most line profiles, and these indicate that there not multiple velocity components along the line of sight. Distributions of excitation temperah at and column density which were estimated from the excitation calculations show the existence of a small(IxEpc),hot(Tex> SOK) core which contains two tempegatlue peaks at -15" east and north of MDS. The column density of HCaN is (1-3):n1014cm-2. Column density at distant position from MD5 is larger than that in the (:entral region. We have deduced that this hot-core has a mass of 10sR1 which i:s about an order of magnitude larger those obtained by previous studies.previous studies.