• Korean Journal of Materials Research
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• v.5 no.6
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• pp.754-762
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• 1995

Strontium titanate(SrTiO$_3$) thin film was prepared on Si substrates by RF magnetron sputtering for a high capacitance density required for the next generation of LSTs. The optimum deposition conditions for SrTiO$_3$thin film were investigated by controlling the deposition parameters. The crystallinity of films and the interface reactions between SrTO$_3$film and Si substrate were characterized by XRD and AES respectively. High quality films were obtained by using the mixed gas of Ar and $O_2$for sputtering. The films were deposited at various bias voltages to obtain the optimum conditions for a high quality file. The best crystallinity was obtained at film thickness of 300nm with the sputtering gas of Ar+20% $O_2$and the bias voltage of 100V. The barrier layer of Pt(100nm)/Ti(50nm) was very effective in avoiding the formation of SiO$_2$layer at the interface between SrTiO$_3$film and Si substrate. The capacitor with Au/SrTiO$_3$/Pt/Ti/SiO$_2$/Si structure was prepared to measure the electric and the dielectric properties. The highest capacitance and the lowest leakage current density were obtained by annealing at $600^{\circ}C$ for 2hrs. The typical specific capacitance was 6.4fF/$\textrm{cm}^2$, the relative dielectric constant was 217, and the leakage current density was about 2.0$\times$10$^{-8}$ A/$\textrm{cm}^2$ at the SrTiO$_3$film with the thickness of 300nm.

• The Korean Journal of Mycology
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• v.22 no.1
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• pp.62-99
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• 1994

The fungal flora of Korean wood-rotting fungi were studied for two years from March of 1990 to February of 1992. Fresh fungi were collected from national parks, local areas, and islands throughout the country. Fleshy fungi of the Aphyllophorales were identified through specimen examination and literature studies. Total 217 species and 1 variety were counted, among which Aleurodiscus cerussatus, Botryobasidium obtusisporum, Ceraceomyces cystidiatus, Erythricium hypnophilum, Grandinia crustosa, Grandinia spathulata, Hyphoderma praetermissum, Hyphoderma roseocremeum, Hypochnicium bombycinum, Hypochnicium detriticum, Hypochnicium lundellii, Laeticorticium roseum, Mycoacia fuscoatra, Peniophora incarnata, Phanerochaete avellanea, Phanerochaete filamentosa, Phanerochaete martelliana, Phlebia lilascens, and Trechispora vaga under the Corticiaceae, Chondrostereum purpureum and Cystostereum subabruptum under the Stereaceae, Tomentella pilosa under the Thelephoraceae, Asterostroma laxum, Hymenochaete cruenta, Hymenochaete fuliginosa, Hymenochaete tabacina, Inonotus radiatus, and Phellinus pomaceus under the Hymenochaetaceae, Antrodia crassa, Antrodia serialis, Ceriporia reticulata, Oligoporus balsameus, Oligoporus guttulatus, Oxyporus cuneatus, Rigidoporus microporus, and Trichaptum laricinum under the Polyporaceae, total 36 species were confirmed as unrecorded species to Korea and are registered here with Korean names and English descriptions.

• Korea Journal of Hospital Management
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• v.7 no.4
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• pp.24-56
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• 2002

The purpose of this study was to analyze the characteristics of socio-demographic, organizational culture, organizational conflict and organizational commitment, and to examine the interrelation of influential factors in the organizational commitment. The data for this study were collected through a self-administrated survey with a structured questionnaire to 1,027 subjects from several medical doctor staff members, nursing staff members, administration staff members, pharmacist, and technical expert of eleven hospitals. The data were collected by self-reporting questionnaire from July 29 to September 7, 2002. In this analysis frequency test, t-test, ANOVA, multiple regression were used. The main results of this research is as following; 1. According to socio-demographic characteristics the respondents' level of the organizational commitment was higher in a administration staff members than others, for males than females, and for employees aged more than forty, as working for longer time, and as higher level of the working position. 2. According to the organizational culture characteristics the progressive culture, affiliative culture, and task-focused culture among many types of organizational culture were moderately and positively correlated with the level of the organizational commitment while the hierarchical culture was negatively correlated. 3. According to the organizational conflict characteristics as the respondents who got less conflict experience in the organization, their level of the organizational commitment was higher. And, technical conflict experiences were expressed greater than hierarchical conflict experiences. 4. According to the job satisfaction characteristics as his or her satisfaction that is about the promotion, working itself, salary, and fellowship in the organizational was higher, the level of the organizational commitment was higher. The most important factor of the satisfactions was the fellowship among the respondents while the level of job satisfaction for the promotion and salary was average. 5. Overall, according to the result of Multiple Regression as older age and longer working hours, the level of the organizational commitment was higher and as a higher level of the satisfaction for the promotion, working itself, salary, and fellowship in the organization, it caused more effective factors for the organizational commitment. 6. According to the result of Multiple Regression for the doctor staff members in special hospitals rather than general hospitals the hierarchical culture and task focused culture was positively correlated with the satisfaction of working itself while hierarchical conflict factors in the organizational conflict characteristics was negatively correlated with the organizational commitment. For the nursing staff members the affiliative culture and the job satisfaction for the promotion, working itself, salary, and fellowship were positively correlated with the organizational commitment. For the administration staff members as the job satisfaction for the fellowship was positively correlated with the organizational commitment. For medical and pharmacy staff members as more working experience, correlation with the organizational commitment was positive. Besides, as he or she has a high perception of the affiliative culture, it caused statistically more effective factors for the organizational commitment. For the skill and technicians, male worker expressed greater organizational commitment in the organization than female worker. And also older age along with higher education also showed higher organizational commitment. Moreover, the job satisfaction for the fellowship was positively correlated with the organizational commitment. This study identified the major effective factors of the organizational commitment and analyzed the differences among the job category. In that respect, it is significant for the study to be able to provide a reference for managing hospital of industrial accident and organizational development. However, this study has a problem, which is not to identify a valuable model for examining the relationship between organizational factors such as organizational culture, conflict, satisfaction, and commitment. Therefore, further study is needed and strengthened in the field of organizational commitment for hospital for industrial accident.

• KSBB Journal
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• v.21 no.3
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• pp.204-211
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• 2006

For the production of the recombinant human interferon-gamma(rhIFN-${\gamma}$) in Escherichia coli, human glucagon and ferritin heavy chain were used as fusion partners. Even though rhIFN-${\gamma}$ is expressed as an inclusion body form in E. coli because of strong hydrophobicity of itself, over 50% of fused rhIFN-${\gamma}$ was expressed as soluble form in E. coli $Origami^{TM}$(DE3) harboring pT7FH(HE)-IFN-${\gamma}$ which encodes ferritin heavy chain-fused rhIFN-${\gamma}$. In the case of using glucagon-ferritin heavy chain hybrid mutant as a fusion partner, 6X His-tag was additionally introduced to N-terminus of GFHM(HE)-IFN-${\gamma}$ for enhancing purification yields of rhIFN-${\gamma}$. Fusion protein HGFHM(HE)-IFN-${\gamma}$ with two 6X His-tag was more effectively bound to Ni-NTA agarose bead than GFHM(HE)-IFN-${\gamma}$ with a 6X His-tag. rhIFN-${\gamma}$ was completely purified from enterokinase-treated HGFHM(HE)-IFN-${\gamma}$ by Ni-NTA affinity column. For high-level production of rhIFN-${\gamma}$, glucose was used as the sole carbon source with simple exponential feeding rate($2.4{\sim}7.2g/h$) in fed-batch process. The effective lactose concentration for the expression of the rhIFN-${\gamma}$ was $10{\sim}20mM$. Under the fed-batch culture conditions, rhIFN-${\gamma}$ production yield reached 11 g DCW/L for 6 hours after lactose induction.

• The Korean Journal of Ecology
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• v.27 no.6 s.122
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• pp.383-390
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• 2004

This study was conducted in three sites, Si-Hwa Lake, Dongman and Seoman island and Janguyeop island, from march, 1999 to september, 2002. The behaviors of pre-breeding season, territorial behaviors, reproductive ecology, foraging sites and behaviors, and the competition of reproduction and foods between intraspecific or interspecific of Eurasian Oystercatcher (Haematopus ostralegus) were observed in each studying sites. The breeding of Eurasian Oystercatcher started on the middle of April in Si-Hwa Lake and on the middle of May in Dongman and Seoman island and Janguyeop island. For intension of pair bond on pre-breeding season, Eurasian Oystercatcher foraged with pair and behaved male-female chasing flight behavior. The pair foraged with male and female before copulation. If other pairs and individuals approached in feeding site of pair, this pair attacked them with piping calling and intruder chasing flight. If continuos serial behaviors were not observed, the discrimination of male-female chasing flight and intruder chasing flight was difficult. Territorial behaviors classified four types; butterfly flight, calling behavior, chasing behavior, fight behavior. The important foraging sites in Si-Hwa Lake are the land place in Daeboo island, tidal flat of Bangameori, tidal flat a front of a stationary net for catching fishes and tidal flat a front of a view station for bird watching. Eurasian Oystercatcher foraged at tidal flat on low water of the tide and foraged at feeding sites near island on flood tide in Dongman and Seoman island. Eurasian Oystercater in Janguyeop island usually foraged feeding sites near island, because water level was not different between low water of the tide and flood tide. Eurasian Oystercatcher competed on foods of intraspecific and interspecific. They chased for taking foods by force in feeding sites and drove out intruders in feeding sites. The foods interspecific competition happened with Black-tailed Gull (Larus crassirostris). Eurasian Oystercatcher was robbed of foods and attacked by Black-tailed Gull. The individual of food competition with Black-tailed Gull was low foods intake rate comparison with other feeding sites and this individual flied out other feeding sites.

• The Korean Journal of Ecology
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• v.27 no.6 s.122
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• pp.325-333
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• 2004

Birds were censused to investigate the composition of landscape structure for bird diversity around Ulsan between May and November 2002. Associations with three main categories of habitat variables were evaluated: 1) amount and type of forest; 2) residual habitats not classified as forest or crops; 3) land-use variables. Cluster analysis of bird community shows the highest forest variables of $79.06\%$, and the others are residual habitat variables ($17.98\%$), land-use variables ($2.94\%$) in spring, and forest variables of $57.77\%$, land-use variables ($23.16\%$), residual habitat variables ($18.47\%$) in autumn, respectively. In Principal Component Analysis of a total of 196 sites, the populations are strongly correlated to Component I ($54.8\%$) based forest habitats and to Component II based on land-use. Species preferring sites were clearly separated with heterogenous forest along the first axis. In autumn, the populations are moderately correlated to Component I based land-use and to component II based forest habitats. Species preferring local habitats were also clearly separated. Fifty three species of 1,700 birds were recorded: Brown-eared Bulbul, Vinous-throated Parrotbill, Great Tit, Tree Sparrow and Black-billed Magpie accounted for over $60\%$ of the observed birds in spring and autumn. The important species were Brown-eared Bulbul, Vinous-throated Parrotbill, Great Tit and Tree Sparrow in spring and autumn. Four habitats in terms of their species richness were computed as follows: Wonhyosan has the highest an expected species number, $E[S_{59}]=19$. Moonsusan has the lowest expected species number, $E[S_{59}]=17$ in spring. In autumn, Kuenamsan has the highest expected species number, $E[S_{63}]=16$. Moonsusan has the lowest expected species number, $E[S_{63}]=12$. Pairwise similarity declined with increasing distance between recording site and recording site from Moonsusan-Wonhyosan (0.62), the same geographical regions clustered separately in a UPGMA cluster tree in spring, and in autumn from Moonsusan-ChungJoksan (0.53).

• The Korean Journal of Ecology
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• v.26 no.1
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• pp.39-47
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• 2003

The leaf aqueous extracts from five gymnosperms plant were investigated for allelopathy with five Hibiscus syriacus varieties. The leaf aqueous extract of Pinus rigida had the highest total phenolic compound of 2.21mg/L, whereas the soil under Pinus koraiensis canopy had the highest total phenolic compound of 1.38mg/L. Fourteen phenolic compounds were isolated from five gymnosperm plants by HPLC. Among them, phenolic compounds were the highest in P. rigida (320.56 g/mg) with the primary compound 5-sulfosalicylic acid (312.55 g/mg). The correlation between leaf total phenolic compound and pH was not significant, while the total phenolic compound of the leaf extract changed soil pH. The relative seed germination of H. syriacus varieties showed 25% was threshold concentration. The germination rates of varieties were similar to the control group or showed slight stimulation to treatment of P. koraiensis extract. H. syriacus Cambanha was similar to the control group or showed stimulation in all treated groups. H. syriacus Seohohyang showed stimulation in both root and shoot growth compared to the control group. In other varieties except Seohohyang, shoot growth was similar to the control group, while root growth was stimulated in all treated groups. The extracts of tested gymnosperms showed significantly more stimulation to transplanted Seohohyang seedlings, whereas others were similar to control or inhibited in the greenhouse. The dry weight of Seohohyang was greater in all treated groups than the control group, while other varieties were inhibited. All gymnosperm extracts stimulated the chlorophyll contents of Seohohyang and H. syriacus Koyoro but other varieties were not significantly affected. Accordingly, it is suggested that Seohohyang seems the most desirable when planted within these five gymnosperms.

• Journal of Ecology and Environment
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• v.29 no.6
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• pp.511-520
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• 2006

The study analyzed the distribution of mammalia per altitude in Gamebong, the highest trail of Juwangsan National Park and confirmed the inhabitation of 22 different species inhabiting in the park. Starting from 200 m to 800 m above the sea level was segmented into 100 m unit. The result of analysis has shown that the Tamias sibiricus is the dominant specie throughout in all segments. Species confirmed to be inhabiting in all segments of research areas were Mustela sibirica, Caproelus pygargus and squirrel. By analyzing the confirmed Field Sign basing from the observation point, it has shown close relations between types of species and population following the increase in altitude (y=-0.0234 + 25.552, $R^2$=0.9296, $F_{0.05}$(1,4)=7.71, p<0.05). However, the result of analysis targeting nine species inhabiting in at least five out of six 100 m segmented units has shown that only two species, Apodemus sgrarius (y=-0.034X+25.2, $R^2$=0.905, $F_{0.05}$(1, 4)=38.169, p<.0.01) and Sciurus vulgaris (y=-0.0154X+ 12.819, $R^2$=0.781, $F_{0.05}$(1, 4)=14.270, p<0.05) were affected by the altitude. Therefore, it is judged that the distribution of species does not follow the altitude variation but follows the food conditions and the structure of habitat. The result of analysis of Box and Whisker Diagram had shown lowest quartile deviation($Q_U-Q_L$) in Nature Restoration Area that is located in $200{\sim}300m$ above the sea level, where hikers are prohibited from entering. In $500{\sim}600m$ above the sea level segment that has similar food environment and trail, it has shown the widest distribution. Further research is required on this segment for the excretion drops of Prionailurus bengalensis, a Grade II class of endangered species, were found on the trails.

• The Korean Journal of Ecology
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• v.26 no.1
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• pp.5-12
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• 2003

Seed germination rate and seedling growth were measured on 6 different species(Phytolacca americana, Eupatorium rugosum, Rumex acetocella, Echinochloa crusgalli, Cassia mimosoides var. nomame, Setaria viridis) treated with leaf extract of E. rugosum. Total phenolic compound and heavy metal were analyzed on leaf and soil with and without E. rugosum. The growth of P. americana seedlings were stimulated by 10% and 25% of E. rugosum water extract treatment. The content of total phenolic compounds in soil was lower than that of leaf extract, and 25% was confirmed as threshold concentration in natural systems because the total phenolic compounds were not significantly different between the control soils and the soil treated with 10%, and 25% extract. Total phenolic compound concentrations of the leaf extracts were highest (1.66 mg/l) with E. rugosum grown under the Quercus forest canopy and lowest (1.09 mg/l) for the plant grown in the mixed forest edge. Leaf extracts of plants selected in different sampling sites (Forest interior, Forest edge, under Pinus Canopy and Quercus Canopy) were significant, while soil extracts were not. Seed germination of R. acetocella and S. viridis were significantly inhibited at over 50% concentrations of E. rugosum, but C. mimosoides var. nomame was not affected at any concentration. The radicle and shoot growth of the native species group were reduced two times more than those of the exotic species group by the treatment of extracts. Especially, the seed germination percentage and dry weight of E. rugosum were greater than those of the control group by treatments with extracts of 10% and 25%. Analysis of aqueous extracts from E. rugosum by HPLC identified 6 phenolic compounds: caffeic acid (460.9 mg/l), benzoic acid (109.7 mg/l), protocatechuic acid (7.3 mg/l), ρ-hydroquinone (6.0 mg/l), cinnamic acid (2.7 mg/l) and hydroquinone (0.23 mg/l). The seed germination of P. americana was also inhibited dramatically by protocatechuic acid and cinnamic acid even though the content of caffeic acid (460.9 mg/l) was the highest among analyzed phenolic compounds. The heavy metal content of soil without A. altissima was higher than that of soil with E. rugosum. Particularly, Al, Fe and Mn was considerably high and most of the heavy metal were accumulated in leaves where a high level of total phenolic compounds was found.

• Journal of Ecology and Environment
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• v.29 no.6
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• pp.551-558
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• 2006

Effects of Pb and $CO_2$ on soil microbial community associated with Pinus densiflora were investigated using community level physiological profiles (CLPP) and 16S rDNA PCR-denaturing gradient gel electrophoresis (DGGE) methods. Two-years pine trees were planted in Pb-contaminated soils and uncontaminated soils, and cultivated for 3 months in the growth chamber where $CO_2$ concentration was controlled at 380 or 760 ppmv. The structure of microbial community was analyzed in 6 kinds of soil samples (CA-0M : $CO_2$ 380 ppmv + Pb 0 mg/kg + initial, CB-0M : $CO_2$ 380 ppmv + Pb 500 mg/kg + initial, CA-3M : $CO_2$ 380 ppmv + Pb 0 mg/kg + after 3 months, CB-3M : $CO_2$ 380 ppmv + Pb 500 mglkg + after 3 months, EA-3M : $CO_2$ 760 ppmv + Pb 0 mg/kg + after 3 months, EB-3M : $CO_2$ 760 ppmv + Pb 500 mg/kg + after 3 months). After 3 months, the substrate utilization in the uncontaminated soil samples (CA-3M vs EA-3M) was not significantly influenced by $CO_2$ concentrations. However, the substrate utilization in the Pb-contaminated soil samples (CB-3M vs EB-3M) was enhanced by the elevated $CO_2$ concentrations. The results of principal component analysis based on substrate utilization activities showed that the structure of microbial community structure in each soil sample was grouped by Pb-contamination. The similarities of DGGE fingerprints were 56.3 % between the uncontaminated soil samples (CA-3M vs EA-3M), and 71.4% between the Pb-contaminated soil samples (CB-3M vs. EB-3M). The similarities between the soil samples under $CO_2$ 380 ppmv (CA-3M vs CB-3M) and $CO_2$, 760 ppmv (EA-3M vs EB-3M) were 53.3% and 35.8%, respectively. These results suggested that the structure of microbial community associated with Pinus densiflora were sensitively specialized by Pb-contamination rather than $CO_2$ concentration.