• 천문학회지
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• 제26권2호
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• pp.115-134
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• 1993

The light curve and radial velocity curve of multiperiodic dwarf cepheid VI719 Cyg (HD200925) with peculiar light curve have been reanalyzed in order to identify the oscillation modes to confirm the helium settling within the envelope. To do these, through the period search for the photometric and radial velocity data from the literature, two different periods were determined and the oscillation modes corresponding to the first and second periods were identified as the fundamental and first radial overtones. Hence the helium settling within the envelope was confirmed from the period ratio. The color excess, metallicity, effective temperature, and surface gravity corresponding to two different modes were determined and it was found that these parameters almost do not depend upon different oscillation mode. By utilizing the surface brightness method, we investigated the variation of angular diameter and radial displacement and it was found that the angular variation is very peculiar. Also by referring to the stellar models, mass and age were determined as $2.7M_{\bigodot}$ and 0.42 Gyr respectively which make this variable star heavier and younger than other multimode dwarf cepheids. Preliminary spectroscopic CCD observations were carried out and it was found that Mg in VI719 Cygni is nearly solar abundent according to the analysis of $5172.68{\AA}MgI$ line which is inconsistent with the photometric result. It was suggested that VI719 Cyg may be classified as a $\rho$ Pup stars according to the photometric characteristics.

• 한국동물위생학회지
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• 제24권1호
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• pp.89-94
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• 2001

In order to investigate the relationship between milk hygienic quality and some environmental factors such as the herd size and types of milking machines, we sampled and examined the level of total bacterial count, coliforms, Staphyococcus aureus, somatic cell counts(SCC) and fat rates in raw milk. of the 84 dairy farms, the prevalence of level on number of standard plate count over 100,000cfu/$m\ell$ and coliforms over 1,000cfu/$m\ell$ in bulk milk were 25.0% and 15.6%, respectively. Also, 2 farms(2.4%) were exceed the level on number of 500cfu/$m\ell$ S aureus in raw milk. The prevalence of dairy herd with first grade of total bacterial count(TBC) according to bucket, pipe line and parlour milking system was 40.0%, 74.0% and 84.0%, respectively. The prevalence of dairy herd with first grade of TBC according to grade 1, 2 and 3 by SCC was 77.8%, 83.2%. and 69.2%, respectively. Therefore, the relationships between hygienic quality in raw milk and the herd size, types of milking machines, were significant. In conclusion, this study could be overemphasized the importance of herd management condition for milk hygienic qualify.

• 한국환경과학회지
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• 제29권11호
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• pp.1141-1151
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• 2020

The impact of sound speed variability in the sea is the very important on acoustic propagation for the underwater acoustic systems. Understanding of the temporal and spatial variability of ocean sound speed in the sea around the Ieodo were obtained using oceanographic data (temperature, salinity). from the Korea Oceanographic Data Center, collected by season for 17 years. The vertical distributions of sound speed are mainly related to seasonal variations and various current such as Chinese coastal water, Yellow Sea Cold Water (YSCW), Kuroshio source water. The standard deviations show that great variations of sound speed exist in the upper layer and observation station between 16 and 18. In order to quantitatively explain the reason for sound speed variations, Empirical Orthogonal Function (EOF) analysis was performed on sound speed data at the Line 316 covering 68 cruises between 2002 and 2018. Three main modes of EOFs respectively revealed 55, 29, and 5% the total variance of sound speed. The first mode of the EOFs was associated with influence of surface heating. The second EOFs pattern shows that contributions of YSCW and surface heating. The first and second modes had seasonal and inter-annul variations.

• 정보과학회지
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• 제1권1호
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• pp.72-74
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• 1983

Traditionally, polynomials have been used to approximte functions with prescribed values at a number of points(called the knots) on a given interal on the real line. The method of splines recently developed is more flexible. It approximates a function in a piece-wise fashion, by means of a different polynomial in each subinterval. The cubic spline gas ets origins in beam theory. It possessed continuous first and second deriatives at the knots and is characterised by a minimum curvature property which es rdlated to the physical feature of minimum potential energy of the supported beam. Translated into mathematical terms, this means that between successive knots the approximation yields a third-order polynomial sith its first derivatives continuous at the knots. The minimum curvature property holds good for each subinterval as well as for the whole region of approximation This means that the integral of the square of the second derivative over the entire interval, and also over each subinterval, es to be minimized. Thus, the task of determining the spline lffers itself as a textbook problem in discrete computer programming, since the integral of ghe square of the second derivative can be obviously recognized as the criterion function whicg gas to be minimized. Starting with the initial value of the function and assuming an initial solpe of the curve, the minimum norm property of the curvature makes sequential decision of the slope at successive knots (points) feasible. It is the aim of this paper to derive the cubic spline by the methods of computer programming and show that the results which is computed the all the alues in each subinterval of the spline approximations.

• 수산해양교육연구
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• 제26권6호
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• pp.1435-1441
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• 2014

The fire took place in the synthetic heat transfer fluid boiler used in production process of medium density fiberboard. This study investigated pressure distribution of the first, second and third passes and the temperature in the fire burner. The boiler's internal fluid is unsteady due to the out of order inverter. As the operation continues, the flame's flow and speed are unsteady. The synthetic heat transfer fluid leak spouted about 120kg/min in the form of vapor in the early period of the fire. The flame extended to the second and third passes. The highest temperature of the second and third pass is $1059^{\circ}C$ and $1007^{\circ}C$, respectively. The synthetic heat transfer fluid spouted through the cracked part of the fire box in the first pass and accumulated on the turn table. Therefore, it is expected that the temperature of the interior of the fire box is above $1200^{\circ}C$. The temperature of the burner rises to a maximum level several times in a short period. On account of that, several explosions occur in the fire burner. Pressure distribution at steady state in combustion furnace is 2~5mAq and pressure distribution at inverter under fault condition in combustion furnace is 10~-53mAq. The decrement of coil thickness measurement for synthetic heat transfer fluid boiler is 0~5mm.

• 한국환경과학회지
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• 제28권1호
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• pp.163-167
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• 2019

In order to collect base line data for setting up bat boxes, we established a total of 30 bat boxes in 2017. The bat boxes were established on the sidewalls of overpass and on the inside of girder bridges. Since establishing bat boxes, we regularly confirmed whether or not they were used; in June 2018, we confirmed that a total of six bat boxes were being used by Pipistrellus abramus and Myotis aurascens. It was confirmed that P. abramus used one bat box each out of five bat boxes, and that many adult females of M. aurascens used a single bat box as a place for maternity roosts. This result is the first use case for setting up bat boxes across the country, and could be used as baseline data to build roosts for bats by setting up additional bat boxes in the future.

• World Technopolis Review
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• 제8권1호
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• pp.8-20
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• 2019

The intent of this paper is to identify key actors of a sustainable Smart City and define metrics that will allow assessment and better management of Sustainable Smart Cities. The paper is organized in two major segments. The first segment reviews the definition, six components, six action items of Smart Cities. It describes briefly a sample Smart City project and presents a selection of different dimensions along which Smart Cities are ranked and the rankings. The segment also discusses the technology architecture of a Smart City and then examines the definition and components of an innovation platform. The second presents the original contributions of the paper. It first introduces the dynamics created seven key actors of a Smart City ecosystem and describes their existing and potential contributions. It then defines Innopreneurship platform and presents a triple bottom line based quality metric to evaluate such a platform. This segment also discusses reengineering an economy and suggests a Smart City's Innovation Platform Score. The actions to be taken by the key actors of a Smart City in order to make it a Sustainable Smart City are described in several subsections. We hope these concepts and metrics will be a good starting point and will be refined over time by others.

• The Journal of Asian Finance, Economics and Business
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• 제8권4호
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• pp.699-707
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• 2021

The objective of this study is to examine the determinants of the liquidity of 17 commercial banks listed on the Vietnamese Stock Exchanges, HOSE, HNX and UPCoM. The study uses the quarterly audited financial statements from the first quarter of 2006 to first quarter of 2020; it includes 496 observations. Data on GDP and inflation are compiled from the International Monetary Fund and the General Statistics Office of Vietnam. Once collected, the data were organized along the line of unbalanced panel data. The results show that total asset size, return on total assets, and credit growth are positively associated with the liquidity of the listed banks; whereas the interaction between the bank size and the return on total assets has a negative impact on the liquidity of commercial banks listed on the HNX, HOSE, UPCoM. In order to maintain good liquidity, commercial banks need to focus on effective credit growth, ensure a high rate of profit over total assets, and at the same time focus on developing the scale of total assets. However, the development of the size of the total assets should be noted in the balance between the total assets and the rate of return on the total assets.

• Journal of Positioning, Navigation, and Timing
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• 제11권1호
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• pp.11-21
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• 2022

Fast Fourier transform (FFT)-based parallel acquisition techniques with reduced computational complexity have been widely used for the acquisition of binary phase shift keying (BPSK) global positioning system (GPS) signals. In this paper, we propose a low computational FFT-based fine acquisition technique, for binary offset carrier (BOC) modulated BPSK signals, that depending on the subcarrier-to-code chip rate ratio (SCR) selectively utilizes the computationally efficient frequency-domain realization of the BPSK-like technique and two-dimensional compressed correlator (BOC-TDCC) technique in the first stage in order to achieve a fast coarse acquisition and accomplishes a fine acquisition in the second stage. It is analyzed and demonstrated that the proposed technique requires much smaller mean fine acquisition computation (MFAC) than the conventional FFT-based BOC acquisition techniques. The proposed technique is one of the first techniques that achieves a fast FFT-based fine acquisition of BOC signals with a slight loss of detection probability. Therefore, the proposed technique is beneficial for the receivers to make a quick position fix when there are plenty of strong (i.e., line-of-sight) GNSS satellites to be searched.

• 한국실내디자인학회논문집
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• 제36호
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• pp.93-101
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• 2003

The first object of this study is to clarify the newly demanded service to the visiter in the museum. And the second is to consider the spatial configuration on the layout of exhibition and the shape of exhibition room from the view points of behavior of appreciation and other methodology. The results of this study are as follows : The exhibition content and structure of Seoul Museum of History formed by a story-line according to the theme of an each zone fixed sequence in an each exhibition that we are achieved. But the layout of exhibition and the shape of exhibition consist on the other hand of the freedom selection. So the problem appeared In the difference of the exhibition content and the layout of exhibition to the behavior of appreciation. It can be said that the concept of exhibition space should be taken into account and the spatial configuration by the completed floor plan in order to satisfy the planning concepts.