• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.2
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• pp.250-261
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• 1999

Based on a set of performance plots relating the design variables to the imposed conditions, an easy-to-use and versatile design procedure for chevron-type multipass plate heat exchangers is developed. In order for the present procedure to cover multipass with unequal passes and non-unity ratio of heat capacity rate, each stream number of transfer unit is adopted as the basic design variable instead of the exchanger number of transfer unit. It is found that there exists a unique relation between the stream and exchanger number of transfer units regardless of the chevron angle and the plate length. In addition, for a given value of the pressure drop the heat transfer area per unit mass flow rate can be expressed in terms of the stream number of transfer unit only. These two relationships in the form of simple plots constitute the framework of design. The sample results in comparison with the available data indicate that the present procedure includes the previous ones as a subset, and that every design method is affected essentially by the selection of specific correlations for the heat transfer coefficient and the friction factor.

• Journal of the Speleological Society of Korea
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• no.68
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• pp.75-98
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• 2005

Korea physiographic province is divided into two provinces which is northern Chugaryung graben zone and southern Chugraryung graben zone. Northern Chugraryung is also divided in to Gema block and Kohan block, and southern Chugraryung dividedinto Han block, Yongnam basin and Honam plain. The above mentioned macro geomorophic units is divided, mainly on the geotectonics. The meso geomorphic units is divided, based upon the regional distribution of topographic characteristic that is plateaus, mountains, mountain range, basins and great plain etc. Micro geomorphic units id into a mountain, a hill, a plain, and a lowland, and then it is formed by selfreliant topographic unit. And micro topographic (fan, peneplain, delta, etc) dealt with a characteristics unit. In this article has a disregarded amallest scale that is included flood plait natural levee, back marsh and oxbow lake etc. Accordingly, it shows macro units are meso units are 5, meso units are 53, micro units are 299. A study method of physiographic provincs prefered to aufsteigende and abstergands methoy. How to organically combine topographic factors can be seen in regional distribution of the peculiar topographic characteristics, for charage teristic of topographic makes a study on the topographic of micro unit such understanding as aufsteigende method. At the same time, since it can be studied systematically from marco unit to micro unit like the absteigende methods, I used both methods. And this establishment of physiographic province based on the scientific method depend on the base map of climate classification. Geology, Soil, Biology. I feel confident that it will be used the basic map for land use map, land classification map, study of geomorphology of Korea. And will be used for study of a topographic standard data.

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.165-172
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• 2014

The distribution of basic nitrogen-containing compounds in three vacuum gas oils (VGOs) with different boiling ranges and their dewaxed oils from the lube base oil refining unit of a refinery were characterized by positive-ion electrospray ionization (ESI) Fourier transform-ion cyclotron resonance mass spectrometry (FT-ICR MS). It turned out that the composition of basic nitrogen compounds in the samples varied significantly in DBE and carbon number, and the dominant basic N-containing compounds in these oil samples were N1 class species. $N_1O_1$, $N_1O_2$, and $N_2$ class species with much lower relative abundance were also identified. The composition of basic nitrogen compounds in VGOs and dewaxed VGOs were correlated with increased boiling point and varied in DBE and carbon numbers. The comparison of the analytical results between VGOs and dewaxed VGOs indicated that more basic N-containing compounds in VGO with low carbon number and small molecular weight tend to be removed by solvent refining in lube base oil processing.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.2 no.2
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• pp.138-150
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• 1997

The late Quaternary stratigraphy of the tidal deposits in the Hampyung Bay, southwestern coast of Korea comprises 1) Unit III (nonmarine fluvial coarse-grained sediments), 2) Unit II (late Pleistocene tidal deposits), and 3) Unit I (late Holocene fine-grained tidal deposits) in ascending order. The basements of the Hampyung Bay is composed of granitic rocks and basic dyke rocks. These three units are of unconformally bounded sedimentary sequences. The sequence boundary between Unit I and Unit II, in particular, seems to be significant suggesting erosional surface and exposed to the air under the cold climate during the LGM. The uppermost stratigraphic sequence (Unit I) is a common tidal deposit formed under the transgression to highstand sea-level during the middle to late Holocene.

• Journal of the Korean GEO-environmental Society
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• v.11 no.8
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• pp.33-40
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• 2010

In this study, evaluation of basic unit of non-point pollutant, which is fundamental evaluation of non-point loading, was conducted using both road point and angle of intersection point in Maesong area, West coast highway by utilizing Event Mean Concentrations(EMC). Concentration of pollutants except heavy metals at these two points rapidly decreased in 30 minutes after start of runoff. According to the results of EMC, for both sampling points, it was determined that the concentrations of TSS(Total Suspended Solid), $BOD_5$(Biological Oxygen Demand), and DOC(Dissolved Organic Carbon) were higher than those of wastewater effluent standard in Korea, however, the concentrations of T-N(Total Nitrogen) and T-P(Total Phosphorus) were lower than those of the standard. In terms of heavy metals, Fe, Pb, and Zn showed higher concentrations than others. When compared with the units established by the Ministry of Environment in Korea, the basic units of $BOD_5$ and T-N in this study were lower. On the other hand, when compared with foreign units, Cu, Pb, and Zn showed approximately 10 times higher concentrations. It was estimated that a long term monitoring should be conducted for obtaining additional data and more reliable basic units for the non-point pollutnats based on the results from this study.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.99-102
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• 2000

In the case of making large vocabulary speech recognition system, it is better to use the segment than the syllable or the word as the recognition unit. In this paper, we study on the basis of making biphone for Korean speech recognition. For experiments, we use the speech toolkit of OGI in U.S.A. The result shows that the recognition rate of the case in which the diphthong is established as a single unit is superior to that of the case in which the diphthong Is established as two units, i.e. a glide plus a vowel. And also, the recognition rate of the case in which the biphone is used as the recognition unit is better than that of the case in which the mono-phoneme is used.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.36 no.5
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• pp.319-327
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• 1987

This paper presents a dynamic programming sucdessive approximation algorithm for scheduling pumped storage hydro plants and shows how this method can be coordinated with the commitment of the thermal units of the system. The general object of operation of pumped hydrostorage plants is the minimization of the overall production cost and the maximization of generation reserves. The basic procedure used to obtain a combined pumped storage-unit commitment schedule is to execute the pumped storage scheduler and unit commitment scheduler iteratively. A combined DPSA algorithm has been presented to coordinate the scheduling of the pumped storage with the scheduling of the thermal units.

• Bulletin of the Korean Mathematical Society
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• v.48 no.3
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• pp.585-600
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• 2011

In this paper we derive an integral formula on an (n + 3)-dimensional, compact, minimal contact three CR-submanifold M of (p-1) contact three CR-dimension immersed in a unit (4m+3)-sphere $S^{4m+3}$. Using this integral formula, we give a sufficient condition concerning the scalar curvature of M in order that such a submanifold M is to be a generalized Clifford torus.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 1996.11a
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• pp.29-38
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• 1996

The purpose of this study is to provide a basic information for the plan of neighborhood facilities as residential environment. For the purpose of this study, this paper is to investigate all criteria of neighborhood unit on the related laws and regulations, As a result, the legal criteria of neighborhood unit has come to no conclusion of terms(the neighborhood life facilities, the life benifit facilities, the neighborhood facilities, etc.) and ranges(the density of population, the number of floors, etc). Therefore a consistent neighborhood unit can be applied to the development plans of new cities as well as new residential areas for the future.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2004.05a
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• pp.145-149
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• 2004

This cases are designated to examine various respect of space program in a museum which are focused on 32 exhibition unit space among the 9 case studies of public museum. Therefore, this study cases offer comprehension of a character and trend about exhibition space through the analysis and classification. Also, through setting up the guide line for the classification of exhibition unit space, the intention of the case study is the use of the case study as guide line and offer the basic data of exhibition space for consideration of exhibition act and moving line caused by the exhibition unit space type.