• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.146-153
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• 1997

An experimental study was performed of natural-convection downward smolder spread across a sawdust bed peripherally enclosed with an insulating container, to examine the effect of the open- ing condition at the top end on downward smolder spread. Experiments were conducted by using relatively coarse sawdust and 25-cm-long cylindrical container The variations of temperature profiles along the bed axis with time were determined far different opening conditions and were com-pared with those in smolder spread from open top to open bottom. It was shown that the smolder zone initiated from open top toward closed bottom penetrates the bed with keeping high peak temperature like the case of open top to open bottom spread, although mean spread rate is smaller. This indicates that the downward smolder zone can be sustained stably if sufficient air or oxygen Is supplied from the back of it by natural convection even if upward draft entering from the bottom of the bed is absent. When the top end was partially closed by mounting a cover after stable smolder spread had begun from open top toward open bottom, the temperature at the peak decreased more than 200 K and the smolder zone became to spread with thickening residue. In this case, the shape of temperature profiles continuously changed or decayed until end-effect at the open bottom end enhanced the reaction. The temperature at the shrunk peak, free from the end-effect, was almost identical with the temperature at the exothermic oxidative-degradation zone in smolder spread from open top to open bottom. from these results, it can be inferred for natural-convection downward smolder spread that the oxidation reaction of the char is very sensitive to the oxygen supply by natural convection in the space above the smolder zone, and that the top end opening condition strongly alters the completeness of reactions, structure, and behavior of the smolder zone.

• Journal of The Korean Astronomical Society
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• v.34 no.3
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• pp.137-141
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• 2001

We derive a new relationship between the giant branch slope as measured in the color-magnitude diagram (K, J - K) and [Fe/H] metallicity for old open clusters. Previously such relationships have been derived for globular clusters, while similar tendency has been expected for open clusters. New derived correlation, [Fe/H]=-17.2($\pm$0.23)GB slope - 1.95($\pm$0.02), is based on a collection of data for 10 old open clusters. Most clusters behave as expected from the theoretical predictions.

• Bulletin of the Korean Mathematical Society
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• v.53 no.1
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• pp.205-214
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• 2016

Any open Riemann surface has a conformal model in any orientable Riemannian manifold of dimension 4. Precisely, we will prove that, given any open Riemann surface, there is a conformally equivalent model in a prespecified orientable 4-dimensional Riemannian manifold. This result along with [5] now shows that an open Riemann surface admits conformal models in any Riemannian manifold of dimension ${\geq}3$.

• Journal of Chest Surgery
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• v.21 no.3
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• pp.462-470
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• 1988

1,597 cases of operation on the cardiovascular disease were performed at the Hanyang University Hospital from 1972 to 1987. Of these, 1,005 cases were open heart surgery. It was started from July 1975. Among the open heart cases, 725 were congenital heart diseases and 280 were acquired heart diseases. In congenital heart cases, 554 were acyanotic and 171 were cyanotic. The operative results were as follows; the overall mortality of cardiovascular surgery was 7.1%, the open heart mortality was 9.5%. This analyses were reported in memory of the achievement of 1,000 cases of open heart surgery.

• Communications of the Korean Mathematical Society
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• v.27 no.3
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• pp.603-611
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• 2012

We introduce the concept of fuzzy $r$-minimal ${\alpha}$-open set on a fuzzy minimal space and some basic properties. We also introduce the concepts of fuzzy $r$-M ${\alpha}$-continuous and fuzzy $r$-M($M^*$) ${\alpha}$-open mappings, and investigate characterization for such mappings.

• Journal of Chest Surgery
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• v.19 no.4
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• pp.672-677
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• 1986

From April, 1984 to August, 1986, 214 cases of cardiovascular surgeries had been performed at Yeungnam University Hospital consisting 158 open heart surgeries and 56 non-open heart surgeries. The leading cardiac anomaly of open heart surgeries was ventricular septal defect which was 43% of congenital heart diseases, and most of remaining non-open heart surgeries were ligating patent ductus arteriosus. We had observed 33 postoperative complications such as wound problems, transient arrhythmia, postpericardiotomy syndrome, bleeding requiring reoperation and so on. 3 cases of surgical mortality were present [2 in congenital heart diseases and 1 in acquired heart disease], which resulting 1.9% of surgical mortality rate in the open heart surgeries.

• Kyungpook Mathematical Journal
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• v.56 no.3
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• pp.745-754
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• 2016

In a graph G = (V, E), a non-empty set $S{\subseteq}V$ is said to be an open packing set if no two vertices of S have a common neighbour in G. The maximum cardinality of an open packing set is called the open packing number and is denoted by ${\rho}^{\circ}$. In this paper, we examine the effect of ${\rho}^{\circ}$ when G is modified by deleting a vertex.

• Journal of applied mathematics & informatics
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• v.39 no.3_4
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• pp.251-257
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• 2021

This article is devoted to introduce the notion of fuzzy cleanly covered fuzzy topological spaces; in addition two strong fuzzy separation axioms are studied. By means of fuzzy maximal open sets some properties of fuzzy cleanly covered fuzzy topological spaces are obtained and also by means of fuzzy maximal closed sets few identical results of a fuzzy topological spaces are investigated. Through fuzzy minimal open and fuzzy maximal closed sets, two strong fuzzy separation axioms are discussed.

• Journal of the Korean Society for Library and Information Science
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• v.43 no.2
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• pp.299-328
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• 2009

In this study, the present condition of 8 Open APIs for books, such as Naver, Daum, Aladdin, Amazon, Google, KERIS, LibraryThing, and OCLC, were compared and analyzed. In addition, the bibliographic records of 167 samples of visible 'light & paraphotic' (DDC 535) classifications were selected from the bibliographic records of the library of C university, and the effectiveness of the Open APIs were compared and analyzed. On the basis of the results of this analysis, 12 Open API application models, which were judged to be useful in expanding the function of the access point of the bibliographic records and enhancing the library catalog using Open API, were experimentally implemented. Various methods of augmenting access points of bibliographic records and expanded library catalogue were investigated using the unique identifier described in the KORMARC fields of 001, 010, 012, 020, 035, 246, 505, 520, 850, 856 for the integrated format for bibliographic data, and Open API. Finally, using Open API for the brief display and detailed display screen as a result of search of the OPAC of the sample bibliographic records, the devices for the expanding library catalog were implemented as examples.

• Journal of the Korea Convergence Society
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• v.8 no.3
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• pp.23-30
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• 2017

OpenADR is a national standard communication protocol of demand response service. OpenADR uses XML message, called a payload, to support logical transaction of demand response service. For this purpose, OpenADR defines a XML element as transaction identifier which is called requestID. Unfortunately, OpenADR 2.0b profile specification describes some information about requestID but, it is not enough for understanding properly. Ambiguous definition of payload transaction makes vulnerabilities of implementing VEN & VTN and confuses mapping OpenADR 2.0b protocol into other smart grid protocols. Therefore, this paper redefines payload transaction to solve an ambiguous information of OpenADR 2.0b profile specification, proposes a model of analyzing payload transaction, and shows how to detect a payload transaction vulnerability in real-world.