• 천문학회보
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• 제42권1호
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• pp.44.4-45
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• 2017

We report the first detection of RR Lyrae variable stars in the Crater II dwarf galaxy, a recently discovered ultra-faint satellite of the Milky Way. Based on B, V time series photometry obtained with the Korea Microlensing Telescope Network (KMTNet) at CTIO, Chile, we have identified ~45 fundamental-mode (ab-type) and ~2 first-overtone (c-type) RR Lyrae stars by adopting template light-curve fitting method. Our preliminary analysis suggests an Oosterhoff-intermediate classification of this galaxy from the mean period of the RRab stars, <$P_{ab}$> ${\simeq}0.63$ days, and the location of them on the period-amplitude diagram. We discuss the properties of the RR Lyare stars in this galaxy.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1965-1966
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• 2008

The manipulation of Boolean functions is a fundamental part of computer science, and many problems in the design and testing of digital systems can be expressed as a sequence of operations. It is mainly a paper of our research on the techniques of Boolean function manipulation using Binary Decision Diagram(BDDs) and their applications for VLSI CAD System. In many practical applications related to digital system design, it is a basic technique to use ternary-valued functions. In this paper, we discuss the methods for representing logical values.

• 한국안전학회지
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• 제15권4호
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• pp.47-55
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• 2000

In this modern age which electric energy is the fundamental source of energy in the industry, electric shock disasters are unavoidable. Although numerous efforts, time, and money have been invested to prevent such electric shock disasters, the number of electric shock disasters are on the increase. In this study, models for equivalent electric circuit are developed for the different types of electric shock which are classified into three groups. The objective of these models is to calculate the electric current flowing through the body at the time of the shock. Based on the analysis, countermeasures to prevent the shock are suggested. The data used in this study are based on 28 actual incidents which occurred in the Daegu area during January of 1995 through June of 1999. The results of this study can be used as a technical manual for workers treating electrical facilities.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제25권2호
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• pp.95-113
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• 2018

A mathematical knot is an embedded circle in ${\mathbb{R}}^3$. A fundamental problem in knot theory is classifying knots up to its numbers of crossing points. Knots are often distinguished by using a knot invariant, a quantity which is the same for equivalent knots. Knot polynomials are one of well known knot invariants. In 2006, J. Przytycki showed the effects of a n - move (a local change in a knot diagram) on several knot polynomials. In this paper, the authors review about knot polynomials, especially Jones polynomial, and give an alternative proof to a part of the Przytychi's result for the case n = 3 on the Jones polynomial.

• 한국농공학회지
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• 제45권1호
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• pp.83-90
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• 2003

In order to offer some fundamental data for recycling the excavated rocks, the component and mechanical characteristics was investigated for the excavated rocks, by means of X-ray diffraction analysis, strength test, slacking test and abrasion test were performed. It appeared that the unconfined compressive strength and the elastic wave velocity were the highest in the sound rock. The dissipation rate by stability tests was found to be high in the case of the slacking index of 98% because of more bedding and more clay minerals. The apparent specific gravity of some crushed aggregate was decreased because they included easily weathered minerals while both the absorption and the abrasion were increased. The results in this study were expected to be useful for recycling the excavated rocks as a concrete aggregate.

• 전자공학회논문지B
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• 제30B권4호
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• pp.21-26
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• 1993

Network systems are of fundamental importance in programmable device in industrial automation, as they essential in order to active group management of integration and coordination. In this papers,MMS implemented on the basis ISO specification for industrial environment. In the MMS-MAP, MMS is situated in the application layer and on the datalink layer. This implemented software was operated with network interface unit which was designed in group objects and service primitives for group management network model system. This function of designed module showed possibility of operation through group state diagram transition in the Mini-MAP environment.

• Structural Monitoring and Maintenance
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• 제6권4호
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• pp.347-364
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• 2019

Two seismic response data from the CSMIP strong motion instrumentation of Pacoima dam are selected: San Fernando earthquake (Jan 13, 2001; ML=4.3) and Newhall earthquake (Sept. 1, 2011; ML=4.2), for the identification of the dam system. To consider the spatially nonuniform input ground motion along the dam abutment, the subspace identification technique with multiple-input and multiple-output is used to extract the dynamic behavior of the dam-reservoir interaction system. It is observed that the dam-reservoir interaction is significant from the identification of San Fernando earthquake data. The influence of added mass (from the reservoir) during strong ground motion will create a tuned-mass damper phenomenon on the dam body. The fundamental frequency of the dam will be tuned to two different frequencies but with the same mode shapes. As for the small earthquake event, the dam-reservoir interaction is insignificant.

• 천문학논총
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• 제30권2호
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• pp.335-339
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• 2015

Using black hole masses which span $10^5-10^{10}M_{\odot}$, the distribution of galaxies in the (host spheroid stellar mass)-(black hole mass) diagram is shown to be strongly bent. While the core-$S{\acute{e}}rsic$ galaxies follow a near-linear relation, having a mean $M_{bh}/M_{sph}$ mass ratio of ~0.5%, the $S{\acute{e}}rsic$ galaxies follow a near-quadratic relation. This is not due to offset pseudobulges, but is instead an expected result arising from the long-known bend in the $M_{sph}{-{\sigma}}$ relation and a log-linear $M_{bh}{-{\sigma}}$ relation.

• BMB Reports
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• 제55권8호
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• pp.363-369
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• 2022

Biomolecular phase separation has recently attracted broad interest, due to its role in the spatiotemporal compartmentalization of living cells. It governs the formation, regulation, and dissociation of biomolecular condensates, which play multiple roles in vivo, from activating specific biochemical reactions to organizing chromatin. Interestingly, biomolecular phase separation seems to be a mainly passive process, which can be explained by relatively simple physical principles and reproduced in vitro with a minimal set of components. This Mini review focuses on our current understanding of the fundamental principles of biomolecular phase separation and the recent progress in the research on this topic.

• Structural Engineering and Mechanics
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• 제72권6호
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• pp.675-687
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• 2019

As the bridges are an integral part of the transportation network, their function as one of the most important vital arteries during an earthquake is fundamental. In a design point of view, the bridges piers, and in particular the wall piers, are considered as effective structural elements in the seismic response of bridge structures due to their cantilever performance. Owing to reduced seismic load during design procedure, the response of these structural components should be ductile. This ductile behavior has a direct and decisive correlation to the development of plastic hinge region at the base of the wall pier. Several international seismic design codes and guidelines have suggested special detailing to assure ductile response in this region. In this paper, the parameters which affect the length of plastic hinge region in the reinforced concrete bridge with wall piers were examined and the sensitivity of these parameters was evaluated on the length of the plastic hinge region. Sensitivity analysis was accomplished by independently variable parameters with one standard deviation away from their means. For this aim, the Monte Carlo simulation, tornado diagram analysis, and first order second moment method were used to determine the uncertainties associated with analysis parameters. The results showed that, among the considered design variables, the aspect ratio of the pier wall (length to width ratio) and axial load level were the most important design parameters in the plastic hinge region, while the yield strength of transverse reinforcements had the least effect on determining the length of this region.