수중 고온 단일 기포의 열전달 해석 연구

윤석태 한국산업정보학회 2024 한국산업정보학회논문지 Vol.29 No.1

Bubbles generated in water receive an upward buoyant force due to the density and pressure difference of the surrounding fluid. Additionally, the behavior, shape, and heat exchange process of bubbles vary depending on the viscosity, surface tension, rising speed, and size difference with the surrounding fluid. In this study, a study was conducted on the behavior, shape, speed, and heat transfer analysis of a high-temperature single bubble rising in a cylindrical water tank. For this purpose, the shape, velocity, and temperature of the bubbles were calculated using theoretical equations, and data were set for comparison with the numerical analysis results. Then, numerical analysis was performed using a commercial program, and the stability of the numerical analysis results according to changes in the grid was confirmed through calculation of the grid convergence index. As a result of the numerical analysis, the rising speed and temperature of a single bubble showed convergence at the D/160 level, and the temperature decrease was confirmed to be the same as that of the surrounding fluid within 0.05 seconds.

무등산 안산암의 행인구조에 관한 연구

윤석태,이선,고영구,오강호 全南大學校 師範大學 科學敎育硏究所 2004 科學敎育硏究誌 Vol.28 No.1

It is important in geological teaching and learning that understandings on rocks might be directly performed in field outcrops. Under the scope, the study developed learning tools on recognitions of rocks in Mudungsan area. In particular, those tools are mainly of understanding the andesites in character, structure and texture. And, it is focused how to make amygdaloidal structures showed from the altered andesites in the area, additionally. The study area is mainly composed of granites, rhyolites, altered andesites, andesite porphyries and tuffs. Minerals forming the amygdaloidal structures are mostly of calcite, quartz, feldspar, epidote, biotite and muscovite. The structures are divided into mono- and poly-mineral filling types in origin. The poly-mineral filling types are subdivided into concentric, colloform, radial, zonal and fingerprinting ones.

영산강 상류역의 수질 특성 및 개선에 대한 고찰

윤석태,오강호,고영구 全南大學校 師範大學 科學敎育硏究所 2005 科學敎育硏究誌 Vol.29 No.1

To consider qualities and improvements for the stream waters of upper Yeongsan River drainage system, total of 54 water samples were taken from Yeongsan main, Hwangryong, Gwangju and Jiseok streams. On the basis of Pipers diagram, water qualities of these streams are corresponded to natural stream water on the whole. But BOD, COD, T-N and T-P are increased into downward in the streams. In particular, these values are highly increased at the encountered area between the above branch and the main streams. From above results, it is suggested to establish special law controlling these streams for water quality improvement as follows; the critical water quality indices to organic contaminations of T-N and T-P, the control of non-point contamination origins in relation with out-fluxing in rainfall time, specific water quality administration to encountered sites between main and each branched stream, and the consideration in the total amount of contamination to each branch streams.

함평군 일대에 분포하는 토양의 토성에 관한 연구

윤석태,고영구,나범수,오강호 全南大學校 師範大學 科學敎育硏究所 2007 科學敎育硏究誌 Vol.31 No.1

On the basis of soil analyses in Hampyeong area, A and B layers are dominantly developed in well weathered soils of the area. Those soil grain sizes are coarse to fine, showing a wide variation, and are poorly sorted. The soil characters directly influence to soil textures, and then, the texture types are classified into several kinds as clay, clay loam, sandy loam, sandy clay, and loam in the area. Soils in the area were formed in variable mixed ones including mountain piedmont and lower flat area environments, arid they are varied into brown soils with much humid material and deep weathered orange ones. Those soil characteristics might be brought on diverse agricultural types as ginseng and bamboo farms putting first of dry and water field ones in the study area.

섬진강 중․하류 퇴적물과 희토류 원소 분포 특성

윤석태,고영구,김종희,신상은,오강호 全南大學校 師範大學 科學敎育硏究所 2015 科學敎育硏究誌 Vol.39 No.1

This study considers analyses on the distribution of rare earth elements and the relations between grain sizes and these elements in the sediments of Seom Jin drainage system. The sediments are of -0.78 to 1.92 ∅ and assigned to very coarse to medium sands. Though the sediments are well to very poorly sorted in ranges of 0.36 ~ 2.32 phi (0.90 phi in average), most is well sorted below 1.0 ∅. Rare earth elements normalized by chondrites show that LREEs are more enriched relative to HREEs in the area. In correlation between grain size and the elements, the elements are strongly positively related with fine sands of 3 ~ 4 ∅. However, the relation between the elements and coarse sands of 0 ~ 1 ∅ is negative. La and Ce are enriched over 1. LREEs are more concentrated than HREEs, but whole REEs are low in the enrichment of the area.

국내은행의 연결 마케팅 강화를 통한 소매금융 경쟁력 제고방안

윤석태 경기대학교e비즈니스연구소 2004 e-경영연구 Vol.1 No.2

용화-설천 지역에 분포하는 백악기 반상화강암의 암석화학 및 유체포유물에 관한 연구

윤석태,박희인 대한자원환경지질학회 1995 자원환경지질 Vol.28 No.5

황룡강 표층퇴적물의 퇴적환경

윤석태,고영구,오강호 全南大學校 師範大學 科學敎育硏究所 2003 科學敎育硏究誌 Vol.27 No.1

To consider sedimentological characteristics of surface sediments in Hwangryong River drainage system, total 23 sediment samples were analyzed in sedimentary texture and facies. The sediments are pebble to coarse sand of 3 .47ø- 1.67ø in grain size, 0.45ø- 3.23ø of poor soπing and very coarse to very fine skewed being biased positively. These sedimentary characters might be influenced by several factors as topography of channel gradient, water charge, surrounding geology. In particular, coarse poπions of channel deposits in the drainage were induced from the weathered products of surrounding area. 환경적으로 수권은 암석권과 상호 유기적이며 밀접한 관계를 가지고 순환한다. 수권과 암석권은 하천을 통하여 인간 활동과 밀접한 관계를 이루고 있으며, 하천으로 유입되는 다양한 물질들은 생물권 및 하상에 퇴적되는 퇴적물에영향을 주어 수중 환경의 변화를 가져온다. 특히 하천에 퇴적 되어진 퇴적물은 존재 형태에 따라 그속에 함유된 중금속의 물리 •화학적 변화 를 수반하여 하천수 중으로 재용출되거나 퇴적물 내에 침전될 가능성이 있기 때문에 하천환경에 대한 영향이 매우큰것으로 알려지고 있다.

해남 지역의 지질에 관한 연구

윤석태 全南大學校 師範大學 科學敎育硏究所 1998 科學敎育硏究誌 Vol.22 No.1

The stratigraphic sequences of the Haenam area are groupped into four units : (1) metamorphic rocks of Pre- cambrian, (2) intrusive rocks of Jurassic period, (3) volcaniclastic and sedimentary rocks of Late Cretaceous and (4) intrusive rocks of Late Cretaceous and Tertiary. Schists and Gneiss complex of Pre-Cambrian and schistose and biotite granite of Jurassic age are exposed at the base of this area on which the thick Cretaceous pyroclastic sediments were deposited. These old rocks are unconformably overlain by the volcaniclastic rocks of Late Cretaceous composed of Hwawon and Hwangsan formation. Biotite granite, micrographic granite, quartz diorite and porphyries of Late Cretaceous and Tertiary intruded into the pre-existed rocks above mentioned.

한국의 금은광화작용

윤석태 全南大學校 師範大學 科學敎育硏究所 1998 科學敎育硏究誌 Vol.22 No.1

This work is a metallogeny on gold-silver deposits in republic of Korea based on broad report of existing literature available. The metallogeny on the gold-silver deposits is mostly related to the granitic rocks. That is, gold-silver deposits distribute with in or near the areas of Daebo and Bulguksa granites. The metallogenic provinces are spatialy associated with some of the felsic to intermediate igneous rock, whereas the metallogenic epochs are temporarily connected with the igneous activities and tectonism. Gold-silver deposits are hosted in the granites and are also in Precambrian schists and gneisses, Paleozoic metasediments and carbonate rocks, as well as in Mesozoic sedimentary and volcanic rocks. In most of the vein deposits, the ores consists of electrum, argentite, native gold and silver, freibergite, polybasite, pyragyrite, miargyrite, tetrahedrite, canfildite, hessaite, jalpaite, tennantite, pearsite, stenbergite, boulangerite, cosalite, tetradymite, Ag-bearing chaicosite, stefanite, energite and base-metal sulfides. Homogenization temperatures and salinities of fluid inclusions range from 130'C to 454'C and from 0.0 wt.% to 12.9 wt.% NaCl equivalent, respectively.