• Korean Journal of Materials Research
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• v.5 no.5
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• pp.568-574
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• 1995

We investigated the effects of B-doping on the growth mechanism of ZnO films. The B-doped ZnO films, which were widely applied for transparent conducting electrode, were deposited by plasma enhanced chemcial vapor depostion(PECVD) using diethylzinc(DEZ), No.sub 2/. and B$_{2}$H$_{6}$. The deposition conditions were a sbustrate temperature of 30$0^{\circ}C$, an rf power of 200, and a chamber pressure of 1 torr. At the given depostion condition, the growth rate of B-doped ZnO thin films was higher than that of undoped ones, but didn't change even with further increasing B$_{2}$H$_{6}$ flow rate and the interplanar distance between(0002) planes was reduced as B atoms substituted Zn sites.s.

• Journal of Applied Biological Chemistry
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• v.42 no.4
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• pp.186-190
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• 1999

Isotope ratio ($^{15}N/^{14}N$) and nitrate-nitrogen concentration in groundwater were measured to investigate the effect of chemical fertilizer and livestock manure on temporal variations in nitrate-nitrogen concentration and to estimate the contribution of fertilizer and manure to groundwater contamination by nitrate. Four study wells from a rural area in Kyonggi province were selected. One well was located on an upper site from a livestock feedlot, and the others were situated at lower sites from the feedlot. The ${\delta}^{15}N$ values were analyzed by a stable isotope ratio mass spectrometer (Micromass, VG Optima IRMS). Reproducibility of the method and precision of the mass spectrometer were below 1.0 and 0.1‰, respectively Even though study wells were located at the same area, nitrate-nitrogen concentrations and ${\delta}^{15}N$ values differed and fluctuated during the sampling period. The ${\delta}^{15}N$ values of well located at upper site from the feedlot were extremely variable (-1.48~20.80‰). The ranges of ${\delta}^{15}N$ value of three wells situated at lower sites from the feedlot were 11.83~20.73 (ave. 16.11), 8.90~11.73 (ave.11.01), and 5.29~12.73‰ (ave. 8.21‰) with increasing distance from the feedlot. The average values of contribution proportion of nitrogen derived from livestock manure to nitrate-nitrogen in groundwater were 79% for the well closet to the feedlot, 44% for the well most distant from the feedlot, and 56% for the well in between the two wells.

• Korean Journal of Veterinary Research
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• v.40 no.3
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• pp.645-652
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• 2000

This study was performed to investigate Mycoplasma (M) spp. infection status of dairy cow in South Korea. Among 8,485 bulk tank milk collected from dairy farms of the 5 areas, 26 samples (0.30%) were positive for Mycoplasma by direct culture method. The isolation rates of Mycoplasma spp. according to the areas were 0.51% in Kyonggi, 0.16% in Cholla, 0.23% in Gyoungsang, 0.12% in Chungchong, and 0.08% in Kangwon. In the species identification test by indirect immunoperoxidase test, 16 out of 26 isolates were identified as M bovis (61.53%), M bovigenitalium (23.07%), M californicum (7.69%), M alkalescens and Acholeplasma laidlawii (3.84%), respectively. The isolation rate of Mycoplasma spp. from 208 quarter milk samples in culling cows due to severe clinical mastitis was 3.0%. These Mycoplasma spp. were identified as M bovis (62.0%), M bovigenitalium (12.0%), M californicaum (12.0%), and M alkalescens (12.0%). This study shows that the bovine mammary gland infected by Mycoplasma spp. is present in some dairy farms and the routine culture test of bulk tank milk samples for Mycoplasma is needed for a high quality milk promotion services.

• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.1052-1056
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• 2004

A secretion signal sequence-selection vector (pGS40) was constructed based on an $\alpha$-amylase gene lacking a secretion signal and employed for selecting secretion signals from Lactococcus lactis ssp. cremoris LM0230 chromosomal DNA. Six fragments were identified based on their ability to restore $\alpha$-amylase secretion in E. coli, and among these, a fragment, S405, conferred the highest secretion activity (84%) in E. coli. Meanwhile, S407, which conferred poor secretion activity in E. coli, was quite active in L. lactis. The results suggested that the efficiency of a secretion signal depended on the host. All six fragments had an open reading frame (ORF) fused to the reporter gene, and the potential Shine-Dalgamo (SD) sequence and putative promoter sequences were located upstream of the ORF. Deduced amino acid sequences from the six fragments did not show any homology with known secretion signals. However, they contained three distinguished structural features and cleavage sites, commonly found among typical secretion signals. The characterized secretion signals could be useful for the construction of food-grade secretion vectors and gene expression in LAB.

• The Korean Journal of Mycology
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• v.26 no.2 s.85
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• pp.287-292
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• 1998

The perfect state of Bipolaris coicis, causing leaf blight of Job's tears, was in duced under in vitro conditions. Eighty nine isolates of the fungus were collected from 17 locations in Korea from 1994 to 1996. They were crossed on Sach's nutrient agar, on which a piece of rice straw was placed, and incubated at $25^{\circ}C$. Pseudothecia were produced only by certain combinations of compatible isolates. Although pseudothecia were usually produced on rice straw two weeks after incubation, asci and ascospores were observed only in a few pseudothecia examined. The pseudothecia were black and globose with protruding ostiolar beaks. The locules were filled with a mass of hyaline and filamentous pseudoparaphyses. Asci were cylindrical to clavate and straight or slightly curved. The ascus wall was bitunicate with short stipes. Ascospores were filiform, hyaline, and arranged parallel to slightly coiled in the asci, measuring $143-166.4{\times}2.6-3.8\;{\mu}m$. Perfect state of the fungus was identified as Cochliobolus nisikadoi (Tsuda, Ueyama & Nishihara Alcorn), based on the morphological characteristics.

• Journal of architectural history
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• v.17 no.3
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• pp.23-43
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• 2008

Seoul has been watched at its symbolic image which is the capital of one nation. since then Joseon was established. So, most of study about Seoul placed too much emphasis on like next; urban organization, palace, government office and public establishment. On the other hand, it is lacking in study of the individual building, the residential district, the change of building-lot. This study is to make up a deficiency from study of Gaokdohyung(家屋圖形site and floor plan). Gaokdohyung(家屋圖形) is drawings of building lots & houses existed in Hanseongbu漢城府(modem Seoul). It is possessed in Jangseogak and all 24 sheets. It is merely 24sheets but has many urban information in that. Housing of number 116 expressed in Gaokdohyung are consist on the house of Sadaebu士天王(noble class) Joongin中人(middle class) Sangmin常民(commoner), Villa(Byeolseo別墅) and connecting stores etc. Houses in Gaokdohyung has characteristic that most building lot is very specious and owners are variety of social position. The study of Gaokdohyung will progress through analyzing diachronic change of individual building lot & house. In the event, results of this study will help to find out change of urban tissue & architecture. So, i intend to seek for entity of urban tissue and urban house in Joseon Period differ from now, and to study out those have been changed continuously forward now.

• Journal of Korean Society of Transportation
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• v.22 no.3 s.74
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• pp.49-58
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• 2004

The first and perhaps the most critical and perhaps the most important step in the process of predicting future traffic volume in a region (Zone) is to estimate the number of trips generated in from each traffic analysis zone. Most trip generation models for urban transportation planning, and highway in Korea are regression models. In Korea the category analysis has not been tried for last decades since the proper data such as the household travel behavior data have not been collected. Recently, the comprehensive household travel behavior survey such as ${\ulcorner}$1996 The Household Travel Behavior Survey${\lrcorner}$, ${\ulcorner}$2002 The Household Travel Behavior Survey${\lrcorner}$ has been done. In this paper, the cross-classification tables of Seoul Metropolitan Area including the City of Seoul and Kyonggi Province are estimated by the category analysis. The tables are compared with regression models and ${\ulcorner}$2002 The Household Travel Behavior Survey${\lrcorner}$ data in terms of predictive capabilities in Seoul Metropolitan Area. Improvement strategies for trip generation forecast in Seoul Metropolitan Area are proposed.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.4
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• pp.473-488
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• 2008

This study was conducted to analyze the perception and observance of traditional Korean holidays and preparation of traditional Korean holiday foods among university students in Seoul and the Gyeonggi area in order to further develop modernize and globalize the foods. The analysis revealed that the traditional Korean holidays with the highest perception and observance was Seollal, followed by Chuseok, Jeongwaldaeboreum, Dongji, Dano and Sambok. Traditional Korean festival foods such as Ddukgook, Mandoogook, Sikhye, Injeolmi, Yookgeijang, Kalgooksoo, Songpyon, Galbizzim, Soondubu and Samgyetang also scored high in perception and preparation. Schools were the most frequent route of introduction to Korean traditional festival foods at a rate of 41.6%. Special educational institutions and schools were also high at introduction rates of 38.3% and 19.5% respectively. The results of this study show that traditional Korean festival foods need to be further developed, as the succession of traditional food culture was the highest among 61.4% and 41.3% of the respondents who answered that the 'standardization of flavor, nutrition and cookery' is the most necessary action to popularize seasonal specialty foods.

• Journal of Families and Better Life
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• v.26 no.5
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• pp.333-354
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• 2008

This study aimed to investigate the role of domain-specific causal mechanism information and domain-general conditional probability in young children's causal reasoning on psychology and biology. Participants were 121 3-year-olds and 121 4-year-olds recruited from seven childcare centers in Seoul, Kyonggi Province, and Busan. After participants watched moving pictures on psychological and biological phenomena, they were asked to choose appropriate cause and justify their choices. Results of this study were as follows: First, young children made different inferences according to domain-specific causal mechanisms. Second, the developmental level of causal mechanisms has a gap between psychology and biology, and biological knowledge was proved to be separate from psychological knowledge during the preschool period. Third, young children's causal reasoning was different depending on the interaction effect of domain-specific mechanisms and domain-general conditional probability: children could make more inferences based on domain-specific causal mechanisms if conditional probability between domain-appropriate cause and effect was evident. To conclude, it can be inferred that the role of domain-specific causal mechanisms and domain-general conditional probability is not competitive but complementary in young children's causal reasoning.

• Nutrition Research and Practice
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• v.9 no.3
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• pp.304-312
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• 2015

BACKGROUND/OBJECTIVES: International students face dissimilar food environments, which could lead to changes in dietary behaviors and anthropometric characteristics between before and after migration. We sought to examine the risk factors, including dietary behaviors, acculturation, and demographic characteristics, related to overweight subjects residing in South Korea. SUBJECTS/METHODS: We conducted a cross-sectional study, collecting data from 142 Chinese international students (63 males, 79 females) in 2013. RESULTS: The mean age of the subjects was 25.4 years, and almost half of them immigrated to South Korea to earn a master's degree or doctoral degree (n = 70, 49.3%). Chinese international students showed an increase in skipping meals and eating speed, but a decrease in the frequency of fruit and vegetable consumption in South Korea compared to when they lived in China. We found a statistically significant increase in weight (69.4 ${\rightarrow}$ 73.9 kg) and BMI (22.4 ${\rightarrow}$ $23.8kg/m^2$) for male subjects (P < 0.001) but no change for female subjects. We also found that overweight subjects were more likely to be highly acculturated and male compared with normal-weight subjects. CONCLUSION: Among Chinese international students living in South Korea, male and more highly acculturated subjects are more vulnerable to weight gain. This study provides useful information to design tailored nutrition intervention programs for Chinese international students.