Journal of the Korean Society for Marine Environment & Energy
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v.8
no.1
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pp.1-8
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2005
We estimated the loadings of nitrogen and phosphorus flowing into Gwangyang Bay front river for monthly interval from April to December of 2003. We analyzed the concentrations of nitrogen and phosphorus in water and estimated the flowing rates of fresh water in 34 rivers. The amounts of water flowing into the Gwdngyang Bay from Sum-Jin River was 51-76% in the total inflow of the river. The river water over 96% of discharge was from Sumjin River, Dong River, Ju-Kyo River, Seo River and Shinkyum River. The flowing patterns of nitrogen and phosphorus into Gwangyang Bay were similar to the flowing of river. The nitrogen and phosphorus loadings into the Bay were higher in July and August than in dry seasons. In particular, the concentrations of phosphorus were high in Namshu River, Deukyang River and Kilho River sewage during in dry seasons. The range of DIN and TN loadings from Sumjim River were 46-66% and 36-64%, respectively. The loading of DIP and TP from Sumjim River were 2-55% and 12-67%, respectively. These results show that the most efficient control of N. p flow into Gwangyang Bay is to restrain the inflows of N, p from Namshu River, Deukyang River and Kilho River and to restrain the flows of N, p from Dong River, Ju-Kyo River and industrial plant. The DIN/DIP atom ratio in river water was about 18 in July and August, while the ratio was more higher in dry seasons than July and August of rainy seasons. The TN/TP atom ratio in river water was about 7 in rainy seasons, while the ratios were higher than 100 in the other months of dry seasons.
Kim, Su Yeon;Lee, Ho Jun;Park, Tae Su;Kim, Soo Geun;Shin, Hye Jung
Clinical and Experimental Pediatrics
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v.49
no.10
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pp.1037-1041
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2006
Purpose : The prevalence of obesity and nonalcoholic steatohepatitis(NASH) was increased in adolescents. This study was performed to observe the prevalence of elevated aminotransferase levels in adolescents and to assess the correlations between aminotransferase levels and obesity related parameters(body mass index, waist circumference, hip circumference, waist to hip ratio and insulin level). Methods : We obtained weight, height, waist circumference and hip circumference from 2,417 male and 1,219 female adolescents. Mean age was $15.7{\pm}0.7$ years old. We measured fasting insulin, aspartate aminotransferase(AST) and alanine aminotransferase(ALT). Obese and overweight were defined as body mass indices(BMI) of more than the 95th, and 85th-94th percentiles, respectively, for age and sex. Results : The number of adolescents with obesity is 324(8.9 percent). 414(11.4 percent) subjects belonged to the overweight group. The average ALT level of obese, overweight and control groups were significantly different(obese : $32.1{\pm}34.3U/L$, overweight : $19.6{\pm}13.6U/L$, control : $12.7{\pm}6.7U/L$, P<0.001). The average AST level was also different according to group(obese : $27.8{\pm}16.5U/L$, overweight : $22.8{\pm}8.6U/L$, control : $20.8{\pm}8.5U/L$, P<0.001). AST and ALT were correlated with anthropometric parameters and insulin level. After multiple regression analysis, waist circumference was the significant predictive value for AST(r=0.234, P<0.001). Waist circumference, BMI and insulin levels were significant predictive values for ALT(r=0.435, P<0.001). Conclusion : The prevalence of abnormal aminotransferase was higher in the obese and overweight groups than control group. Waist circumference was useful to predict abnormal aminotransferase levels.
Kim, Song-Mun;Hwang, Ki-Hwan;Park, Hong-Ryeol;Cho, Jun-Mo;Park, Su-Jin;Shin, Hyon-Po;Hur, Jang-Hyun;Han, Dae-Sung
The Korean Journal of Pesticide Science
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v.2
no.2
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pp.102-107
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1998
The objective was to know if seed potato farmers in Kangwon alpine area control weeds effectively and use herbicides properly to control weeds. Seed potato farmers in Pyongcbang, Hoengsong, and Kangnung have noxious weeds, such as marsh pepper, lambsquarters, barnyard grass, mugwort, asiatic dayflower, hairy carbgrass, ladysthumb, common chickweed, field horsetail, and common purslain, in their farmyard. These are controlled by a combination of physical and chemical weed control methods. However, several weeds such as marsh pepper, field horsetail and, mugwort are poorly controlled by 2-fold amount of several herbicides, including paraquat, pendimethalin, and metribuzin (58% of the answered). Herbicides are not selected and used in a proper manner by seed potato farmers: most of farmers selected herbicides by their experience (51% of the answered) and dealers recommendation (34% of the answered), while only a few farmers of the answered took advantage of the Farmers Handbook for Herbicide Application. In addition, the selected herbicides, including non-registered ones such as paraquat and fluazifop-butyl, are applying three to five years in a succession. With these improper selection and usage of herbicides, sixty-seven percent of the answered farmers have experienced crop damage and seventy-five percent have poisoning. We conclude that a systemic educational program for the proper selection and use of herbicides is needed for seed potato farmers in Kangwon alpine area.
The present study aims to monitor pesticide residues in cut flowers collected from the farms and markets. Cut flowers used in this study included rose, lily and chrysanthemum collected from June to September, 2008. Samples were collected once from farms in Hwasung, Goyang (Gyeonggi-do), Inje (Gangwon-do) and thrice from wholesale market in Namdaemunm, Yangjae and Gangnam (Seoul). Total of 24 pesticides (12 fungicides, 11 pesticides and 1 acaricide) were detected from samples collected from farm and total of 64 pesticides (25 fungicides, 36 pesticides, 1 acaricide and 2 fungicides) were detected from samples collected from wholesale market. The highest detection frequency of pesticide from farm was for carbaryl (15%) and for boscalid, fluacrypyrin, fluquinconazole, methomyl, pyraclostrobin, trifloxystrohin (10%), with overall detection of $0.1-36.99\;mg\;kg^{-1}$. While the highest detection frequency of pesticides from wholesale market was for carbaryl, fluquinoconazole and kresoxim-methyl (18.52%), methomyl (16.6%), and methiocarb and thiacloprid (12.96%) with overall detection amount of $0.1-56.2\;mg\;kg^{-1}$. Higher amount of pesticides were detected in leaves than in flowers. Among the pesticides detected, detection frequency of unregistered pesticides for rose, chrysanthemum and lily was 55%, 60% and 63% collected from farms and 47%, 60% and 89% collected from markets, respectively. These pesticides require registration and further monitoring in floricultural crops.
An analytical method for detecting metamifop residue in paddy water, soil, and rice with high performance liquid chromatography (HPLC) was developed. Water was extracted with ethyl acetate before analyzing by HPLC. Soil residues were extracted with acetone under acidic condition and after purifying with $Extrelut^{(R)}$ NT, and silica SPE, the residue was analyzed by HPLC. For residue analysis in rice, the procedure involved extraction with acetone, purification with $Extrelut^{(R)}$ NT, partitioning between acetonitrile/hexane, purification with silica SPE cartridge, and analysis by HPLC. The limit of detection (LOD) was 1.0 ng, limit of quantitation (LOQ) was 3.0 ng, and method limit of quantitation (MLOQ) were 0.001 mg/L for paddy water, 0.01 mg/kg for rice and soil, respectively. Standard calibration curve shows linearity from 0.05 mg/kg to 5.0 mg/kg ($R^2=0.9999$). The recoveries in fortified paddy water were $91.3{\pm}3.5%$ (0.01 mg/L level) and $93.2{\pm}6.3%$ (0.05 mg/L level). The recoveries in fortified paddy soils were $92.5{\pm}4.0%$ (0.1 mg/kg level) and $92.7{\pm}4.0%$ (0.5 mg/kg level) in soil A, while, $102.3{\pm}4.4%$ (0.1 mg/kg level) and $98.9{\pm}7.9%$ (0.5 mg/kg level) in soil B, respectively. The recoveries in fortified rice were $93.0{\pm}6.9%$ (0.1 mg/kg level) and $85.0{\pm}3.5%$ (0.5 mg/kg level). This method was proved to be effective and can be used to determine the metamifop residue in paddy water, paddy soil, and rice.
The purpose of this study is to analyze the current status and condition of children's playgrounds in K which parents recognize as in Gyeonggi-do and provide basic data for the qualitative environment for daily outdoor play of young Children. To do so, a survey of 269 parents living in Gyeonggi-do was conducted and reconstructed based on the advanced research related to outdoor play. Also it was evaluated and revised after consultation with 3 children education specialists. The repossessed questionaries were frequency-analyzed with SPSS 20.0 program. The result of the analysis on outdoor playgrounds is in the following. First of all, it was analyzed that parents required 1 or 2 hours for their children to play outdoors in a type of "forest playgrounds." Moreover, they said that it was really important for the children to feel "interesting and funny" during the outdoor play, and they recognized that the play would be helpful for the children's socialization. However, they felt that a risk factor of the outdoor play was "a vehicle risk in streets." Secondly, the study suggested that there were outdoor playgrounds around parents' houses, and a type of the outdoor play was "a playground installed in the apartment complex." Furthermore, most of the parents weren't satisfied with the outdoor play because the apartment neglected the management of the playgrounds, and there were no playing facilities that were good enough to derive children's curiosity and adventurous spirit. The result also showed that most of the children played outdoors with "their mothers," and they participated in indoor activities, especially playing a game or watching TV rather than outdoor activities after attending a children educational institute. Lastly, when it comes to areas of outdoor play to be improved, it was necessary to "expand playgrounds that children can use for each season," build "safe playgrounds" for a type of the outdoor play," provide "playing spaces" for a spatial type, and "control vehicles around the playgrounds and deal with dangerous things" to prevent safety accidents. The result can expand the understanding of outdoor play for Young Children and offer discussions about the relevant organizations and studies.
In the last decades, technology-oriented small firms, i.e. venture businesses, have been increasingly engaged in R&D collaborations with external parties as strategic means for technological innovation. Despite ample evidence on the benefit of such collaborations for the firms, there has been less attention to examining whether and how the firms' social interactions with cooperating partners and their managerial characteristics contribute to that benefit. Drawing on the theories of social capital and entrepreneurial orientation, this study is to remedy this gap. The theory of social capital, referring to a sum of the value and potential resources embedded in social relationships of collectives, provides an integrated view of social factors among cooperating partners, e.g. strong ties, network stability, trust, reciprocity, shared vision and value. It categorizes these factors into structural, relational, and cognitive dimensions of social capital. Entrepreneurial orientation theory captures firms' managerial characteristics as a combination of innovativeness, proactiveness, and risk-taking. This addresses firms' managerial process to utilize and combine internal and external resources for wealth creation and opportunity realization. Against this background, this study investigates what roles social capital among cooperating R&D partners and entrepreneurial orientation of the collaborating firms play for collective performance improvement in R&D collaborations. In terms of the collective performance, this study adopts two indicators: technological competitiveness and business performance. Technological competitiveness refers to the contribution of a technology developed by a cooperative R&D project to competitive advantage of a firm while business performance is defined as the financial and economic outcome of a collaboration. Using a sample of 218 Korean ventures engaging in R&D collaboration with external parties, the author finds the significant effects of social capital (i.e. structural, relational, and cognitive dimensions) and entrepreneurial orientation (i.e. innovativeness, proactiveness, and risk-taking) on both of the technological competitiveness and the business performance. Further, the higher the social capital among R&D partners, the more likely it is to foster the entrepreneurial orientation at firm-level. Most importantly, the entrepreneurial orientation at firm-level is an significant mediator of the relationship between social capital and collective performance. Beyond these novel empirical findings, this study contributes to the literature on R&D collaboration. The findings' implications for management and policy are deeply discussed in the conclusion.
Journal of the Korea Academia-Industrial cooperation Society
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v.14
no.8
/
pp.3958-3970
/
2013
This study was carried out to grasp the job stress and intention to change their jobs of nurses at general hospitals by their socio-demographic, job-related and health-related behavior characteristics and especially to investigate their relationship to the job stress and intention to change their jobs. The subjects were 355 nurses working at three university hospitals located in Daejeon City, and data were collected by a survey using self-administered questionnaires structured from April 1 to May 31, 2012. As a results, the average point of the nurses' intention to change jobs by the causes for job stress was significantly higher in the boss group with low support than in that with high support while it was higher in colleague group with low support than in that with high support. To look into the correlation between the points of intention to change their jobs and the causes for job stress, their intention to change their jobs showed a significant negative correlation to the boss's support and colleagues' support while there was no significant relationship with job demands and job autonomy. As a result of hierarchical multiple regression, age, drinking coffee, department, job satisfaction, the boss's support and colleagues' support were selected as significant related variables affecting the nurses' intention to change their jobs and these variables' descriptive power was 29.4%. Viewed from the above results, it is suggested that the nurses' job stress and intention to change their jobs has a significant relationship with various variables such as socio-demographic, health-related behavior and job-related characteristics. In addition, there were a significant positive correlation between the causes for the job stress cause and intention to change their jobs, and among the causes for the job stress, support by their boss or colleagues turned out to be those affecting their intention to change their jobs. Thus, it is considered that it is necessary to minimize the nurses' job stress and at the same time to seek for specific measures for preventing their turnover.
Effects of harvest date, number of the leaves remained on stump after flower cutting, duration of cold treatment on the growth and flowering of L. elegans 'Connecticut King' bulb were tested. Shoot emerging rate increased over 90% by delayed cold treatment, late harvesting time and more leaves remained. Flowering rate increased over 90% when conducted cold treatment of 90 days to the premature bulb at flowering date, the bulb matured for 50 days with 10 leaves and the bulb matured for over 30 days with 20 leaves, and when conducted cold treatment of 50 days to the bulb matured for over 30 days with all leaves. Delayed cold treatment duration shortened days needed to shoot emergence and flowering. Especially days to flower of the premature bulb at flowering date were the shortest of all treatments, and can be flowered within 100 days after planting. In generally, plant height, number of flowers per plant and stem diameter generally increased by longer bulb maturing period after flower cuting, and the premature bulb harvested at flowering date showed poor growing and flowering responses. But, if used the larger size bulb, it is believed that the prematured bulb can be forced to flower normally in current year without bulb maturing period.
This study was conducted to estimate the effects of year, age of dam at calving, farm and lactation period on milk yield with the data of 4,008 cows' records which were collected at 32 farms by Korea Animal Improvement Association from 1985 to 1989. The results obtained in this study are summarized as follows: 1. The average performance of the dairy cattle in the study were $5,959.23{\pm}2,113.03kg$ in actual milk yield, $49.19{\pm}22.77$ months in age of dam at calving, $27.11{\pm}5.13$ months in age at first calving and $255.11{\pm}79.68$ days in lactation period. 2. The percentages of variance component for different sources were 29.39% for the residuals, 1.91% for years, 4.86% for age at calving, 8.89% for farms and 54.94% for lactation period. 3. The overall mean of least-square estimate on the milk yield was 6,229.31kg. In the effects of year, the least-square means of milk yield were estimated 6,000.76kg in 1985-1987, 6,028.11kg in 1988 and 6,659.07kg in 1989. 4. The least-square means of calving age on the milk yield were estimated 5,456.01kg in less than 24 months, 6,565.48kg in 61-66 months which were the highest least-square means. This effects were gradually increased until the 61-66months and gradually decreased after the 61-66months, with highly significant differences among different months of age at calving(p<0.01). 5. In the effects of farm, the least-square means of milk yield were estimated 4,959.50 kg in the lowest farm and 7,497.07kg in the highest farm. Among the milk yield of each farm the effects showed highly significant difference(p<0.01). 6. The least-square means of milk yield in the effects of lactation period were gradually increased with the lapse of the lactation period. Among the lactation period the effects showed highly significant difference(p<0.01).
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