• Korean Journal of Construction Engineering and Management
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• v.5 no.2 s.18
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• pp.136-143
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• 2004

This study presents a risk management methodology using fuzzy theory for early construction stage and is focused on risk identification and risk analysis. This study identifies various risk factors associated with activities clearly construction stage, then establishes the Risk Breakdown Structure(RBS) by classifying the risks into the three groups; Common risks, risks for Earth works, and risks for Foundation works. The risk analysis method presented in this study is based on the RBS that has two levels such as upper level and lower level. The risk exposure of lower level risk factors is assessed by fuzzy inference. The weight of risks is estimated by fuzzy measure. Then, the estimated risk exposures and weights are aggregated to assess the risk exposure of upper level risks by Choquet fuzzy integral. The risk exposure of upper level risks determine the priority of risk factors in view of risk management. This study performs case study to validate the proposed method. The result of case study shows that the methodology suggested in this thesis would be utilized well in evaluating risk exposure.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.2
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• pp.125-130
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• 2018

The technology development of a high performance upper stage engine for a GEO(GEostationary Orbit) KSLV(Korea Space Launch Vehicle) is undergoing in Korea Aerospace Research Institute. KSLV is composed of an open cycle engine with gas generator, which is for a low orbit launch vehicle. However the future GEO launch vehicle requires a high performance upper stage engine with a high specific impulse. The staged combustion cycle engine is necessary for this mission. In this paper, current progress and future plan for staged combustion cycle engine development is described.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.6
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• pp.723-730
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• 1995

Effects of leaf and pod removal on changes in dry weight and protein content of soybean [Glycine max (L.) Merr.] cultivar 'Hwangkeumkong' were measured at the research farm of Korea University in 1992. The upper 40% and lower 60% of leaves and pods were subjected to treatments at the growth stage of beginning pod(R3). Leaf dry weight of lower part was increased by upper leaf-lower pod removal, but seed dry weight of upper part was decreased. The upper leaf-lower pod removal also increased stem dry weight and decreased upper pod dry weight. Protein content was higher in lower leaves than upper leaves. Seed protein contents were decreased both upper leaf-lower pod removal and lower leaf-upper pod removal treatments. The upper leaf-lower pod removal showed the highest leaf and the lowest seed protein quantities among the five treatments. These results indicated that protein sources were moved from lower to upper parts but weak in remobilization from leaves for the long distance translocation during the reproductive growth period of soybean plants.an plants.

• Journal of the Korean earth science society
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• v.31 no.1
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• pp.18-35
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• 2010

Facies analysis of the Late Triassic Hajo Formation, the lowest stratigraphic unit in the Chungnam Basin, shows that the lower part is composed mainly of breccias or conglomerates; the middle part, conglomerates; and the upper part, conglomerates and sandstones. The formation consists of 13 facies, which include horizontally stratified clastsupported conglomerate, clast-supported massive breccia, matrix-supported massive breccia or conglomerate, matrixsupported graded conglomerate, massive pebbly sandstone, horizontally laminated sandstone, massive sandstone, graded sandstone, inversely graded sandstone, planar cross-bedded sandstone, trough cross-bedded sandstone, low angle crossbedded sandstone, and massive mudstone. These are grouped into 4 facies associations (FA). FA I consisted of clastsupported and matrix-supported massive breccias presumably deposited in the talus or upper fan delta environment. FA II consists of matrix-supported massive conglomerate and horizontally stratified clast-supported conglomerate of cobble size and it seems to have been deposited in the upper fan delta environment. FAIII consisted of matrix-supported massive conglomerate of pebble size, horizontally laminated sandstone and massive sandstone may have been deposited in the middle fan delta environment. FAIV consists of massive pebbly sandstone, horizontally laminated sandstone and massive sandstone and presumably was deposited in the lower fan delta environment. In general the Hajo Formation is interpreted to have been deposited at the talus/upper fan delta environment in early stage; it might have been deposited in the alternating environments of upper and middle fan delta in middle stage; and it seems to have been deposited in alternating environments of middle and lower fan delta in late stage.

• Journal of Chest Surgery
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• v.25 no.4
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• pp.398-405
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• 1992

Twenty nine adult patients underwent surgical esohpagectomy and one, bypass procedure for documented carcinoma of esophagus and cadiac portion of stomach at Chonnam National University Hospital from Jan 1986 to April 1991. There were several kinds of esophagectomies including through transhiatal, left thoracotomy only, laparotomy and thoracotomy, and laparotomy and right thoracotomy and cervical incision. Twenty five and squamous cell carcinoma and 5, adenocarcinoma. The tumor locations were the upper third in 3, middle third in 12, lower third in 10 and cardiac portion of stomach in 5. After operation, 8[27%] patients were classified in Stage IIa, 6[20%] patients in Stage IIb, 15 patients[50%] in Stage III and one patient in Stage IV. Major postoperative complications included anastomotic narrowing in 3, limited suture line leak in 2, wound infection in 2, hoarseness in 2, pseudomembraneous enterocolitis in 1 and herpes zoster in 1. There was no death within 30 days of operation. Ten months survival was 100% for patients with Stage lIa, 67% for patients with Stage IIb, 50% for patients with Stage III. Furthermore, 20 months survival was 75% in IIIa, 33% in IIb, and 40% in III. But there were no significant differences in survivals among the stage. The actuarial survival is 58% at one year and 41% at two years, The periods of average survival is 589 days after operation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.4
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• pp.324-329
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• 1993

Effects of leaf and pod removal on changes in leaf and seed number, and leaf, seed, pod and stem dry weight of soybean [Glycine max (L,) Merr.] cultivar ‘Hwangkeumkong’ were measured at the research farm of Korea University in 1992. The upper 40% and lower 60% of leaves and pods were subjected to treatments at the growth stage of beginning pod(R3). Leaf number and dry weight of lower part were increased by upper leaf-lower pod removal, but seed number and dry weight were decreased. Upper leaf-lower pod removal increased lower stem dry weight and decreased upper pod dry weight. Leaf-seed ratio of the upper leaf-lower pod removal was the highest with 3.54 and harvest index was the lowest with 27% among the treatments. Lower leaf-upper pod removal showed that more assimilates from upper leaves were translocated to lower seeds than from lower leaves to upper seeds in upper leaf-lower pod removal treatment.

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.13-14
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• 2003

It is generally well known that Quaternary is characteristic geologically in terms of glacial and interglacial repeats and their associated unconformity formation. This paper deals with the first finding of the characteristic and significant meaningful unconformity between Holocene and late Pleistocene, which implies submergence and emergence of the tidal sedimentary basin along the western coastal zone of Korea during interglacial stage(IOS-5e) and glacial time(IOS-2). The stratigraphy of intertidal deposits in the Haenam Bay, western coast of Korea shows two depositional sequence units (Unit I of Holocene and Unit II of late Pleistocene) bounded by an erosional surface of disconformity. The disconformity is related to the latest Pleistocene sea-level lowstands (probably during the LGM). The Unit II is interpreted as intertidal deposit showing tidal sedimentary structures and crab burrow ichnology and has two parts (the upper part and the lower part) showing different lithology and character. The upper part of Unit II shows characteristic subaerial exposure features (emergence) and its related lithology. Such subaerially exposed upper part (more or less 4m to 5m in thickness) is characterized by yellow-brownish sediment color, cryoturbat-ed structure, crab burrow ichnofacies and high value of shear strength. Geochemical and clay mineral analyses of the upper part sediments also indicate subaerial exposure and weathering. In particular, very high value of magnetic susceptibility of the upper part in comparison to that of the lower part is interpreted as pedogenetic weathering during the subaerial exposure period.

• Journal of the Korean Society of Tobacco Science
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• v.5 no.2
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• pp.9-15
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• 1983

The effect of leaf dehydration process and air flow capacity of bulk curing on physical properties and composition of cured leaves was studied, respectively, during flue- curing. Cured leaves from excessive moisture during yellowing stage and those from rapid dehydration Process inevitably during later stages, tend towards lower equilibrium moisture contents, higher shatter index, hither protein nitrogen, and leaf scalding or deterioration of Beaves with redish cast. Early dehydration at the yellowing stage re suited in increasing of p Bamitic, stearic, linoleic, and linolenic acid contents, but showed reduction of brightness difference between upper and lower surface of the cured leaves, Leaf surface lipid decreased with the progress of curing stages, more conspicuously during later stage. Lowering air flow capacity of fan by 50oye during stem drying stage resulted in increasing of leaf surface lipid and 25oye decreasing of electric power consumption , but curing period and kerosene consumption were not affected.

• Journal of Korean Institute of Industrial Engineers
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• v.33 no.2
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• pp.213-220
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• 2007

This paper considers a two-stage hybrid flow shop scheduling problem for the objective of minimizing the number of tardy jobs. Each job is processed through the two production stages in stages, each of which has multiple identical parallel machines. The problem is to determine the allocation and sequence of jobs at each stage. A branch and bound algorithm that gives the optimal solutions is suggested that incorporates the methods to obtain the lower and upper bounds. Dominance properties are also suggested to reduce the search space. To show the performance of the algorithm, computational experiments are done on randomly generated problems, and the results are reported.

• Journal of the korean academy of Pediatric Dentistry
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• v.3 no.1
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• pp.7-11
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• 1976

The author measured the degree of development and the eruption pattern of first permanent molars with orthopantomography in 553 Korean children(male; 302, female; 251) from 4 to 9 years old. The orthopantomographs were obtained from dept. of pedodontics, college of dentistry, Seoul National University. The results of the studies were as follows: 1. Upper first permanent molars were erupted with distal inclination of about 30 degrees in the early stage and they gradually moved in the mesial direction by bodily movement of the tooth to be in contact with the disto-proximal surface of primary secondary molars in the late stage. 2. Lower first permanent molars were erupted with mesial inclination in the early stage and moved mesially by tipping movement of the tooth to be in contact with the disto proximal surface of the second primary molars in the late stage. 3. The eruptive forces were considered to be main etiologic factors of space closure after the premature loss of primary molars.