• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.2
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• pp.195-201
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• 1983

This study was conducted to find out the damage of rice root nematodes on rice and determine the economic injury level. In pot experiments, rice root nematode, Hirschmanniella imamuri, suppressed the growth and reduced yield of a rice, Milyang 23, above critical levels. Tillering was depressed above 5, 000 nematodes per pot inoculum levels. Heading was also delayed by 6 days when inoculum level was above 20, 000. Weight of roots and grain yield in rice plants which inoculated with 20, 000 nematodes/pot were reduced by 41% and 31%, respectively. Economic injury level of rice root nematode appeared to be 1, 500 nematodes per 30g of fresh root on Aug. 30.

• Journal of Digital Contents Society
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• v.16 no.3
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• pp.417-424
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• 2015

The research of occupational injury for safety and health is a comparatively recent occurrence. As labor activities took place regarding to employee concerns in industrial uprising, human resources health was tried to enhanced as a labor safety subject. Noticing that traditional statistics approach has limitations in learning future forecasting and major factors causing occupational injuries in each industry, Korean Government initiated a quantitative systematic simulation model project to analyze how the annual injury rate has been dropped and stays in a level for recent years. From this motivation and the project, system dynamics models have been developed to explain the mechanisms for reducing annual injury rate, and the mechanisms quantitatively. The main cause effects for the reduction of annual injury rate were due to the government driven investment on safety facilities. In overall viewpoint the gain achievable from these efforts has been reached a saturated level. However, it could reduce the annual injury rate if you chose the industry and size carefully. The model for forecasting, major injury factors, safety budget and allocation are introduced and analyzed, and Analyzing occupational injury related factors can also reduce employee injury and disease related costs, including medical care, quit, and disability assistance costs.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.407-411
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• 2008

This study was conducted to estimate the economic injury level (EIL) and economic threshold (ET) of the green peach aphid, Myzus persicae, on Chinese cabbage (Brassica campestris var). The changes of biomass of Chinese cabbage and M. persicae density were investigated after introduction of M. persicae at different density (0, 2, 5, 10, 15, and 20 per plant; inoculated at 10d after planting). The densities of M. persicae largely increased from the above initial densities to 0, 92.3, 177.4, 406.9, 440.4, and 471.3 aphids per plant at 18d after the initial inoculation, respectively. The biomass of Chinese cabbage significantly decreased with increasing the initial inoculated density of M. persicae: 602.0, 264.2, 262.0, 109.3, 151.0, and 67.3 g in above plots with different initial densities, respectively. The relationship between cumulative aphid days (CAD) and yield loss (%) of Chinese cabbage was well described by a nonlinear logistic equation. Using the estimated equation, EIL of M. persicae on Chinese cabbage was estimated 25 CAD per plant based on the yield loss 13%, which take into account of an empirical gain threshold 5% and marketable rate 92% of spring Chinese cabbage. Also, ET was calculated at 80% of EIL: 20 aphids per plant. Until a more elaborate EIL-model is developed, the present result may be useful for M. persicae management at early growth stage of Chinese cabbage.

• Korean journal of applied entomology
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• v.46 no.3
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• pp.409-414
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• 2007

Economic injury levels and economic thresholds were estimated for the american serpentine leafminer (Liriomyza trifolii) on greenhouse eggplant. Liriomyza trifolii density was increased until the late June and decreased after the July in innoculation on may 17. Growth of an aerial plants and fruits were not different in treatment respectively. But total number of fruits and yields were decreased on higher inoculation density. Whereas the rate of yield loss was increased. The rates of damaged leaf by L. trifolii were increased on higher inoculation density and the peak was 65%. The number of commodity fruits and the rates of commodity fruit were become lower than non-treatment (72.2%). The rates of damaged leaf area were 5.3, 11.7, 19.7, 25.7% on inoculation densities and the rates of yield loss were 0.6, 4.8, 9.8, 14.7%, respectively. There existed close correlation between rate of yield loss and inoculation density (Y = 0.76779X + 0.298354, $R^2\;=\;0.9599$). Considerated of the results, the economic injury levels of L. trifolii on eggplant greenhouse was 6.1 adults per 4 plant and the economic thresholds was 4.9 adults per 4 plant.

• Korean journal of applied entomology
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• v.53 no.2
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• pp.93-96
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• 2014

This study was conducted to determine the economic injury levels and control thresholds for the striped cabbage flea beetle, Phyllotreta striolata (Coleoptera: Chrysomelidae), on Chinese cabbage at two different planting times. The number of inoculated adults per 10 cabbages was 0, 2, 4, 8, and 16 at the early developmental stage of the cabbage5 days after planting) and 0, 10, 20, 30, and 40 at the middle developmental stage (30 days after planting). Damages to the leaves at the first inoculation were 2.5-21.1% and at the second inoculation were 1.8-26.3% after harvesting. The linear relationships between population density and yield reduction were as follows: Y = 1.3475X + 2.135 ($R^2$ = 0.8699) at the early developmental stage and Y = 0.703X - 1.78 ($R^2$ = 0.966) at the middle developmental stage. On the basis of these results, the economic injury levels caused 5% loss of yield; there were 2.1 adults per 10 Chinese cabbage at the early developmental stage and 9.6 adults per 10 Chinese cabbage at the middle developmental stage.

• Research in Community and Public Health Nursing
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• v.26 no.2
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• pp.100-107
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• 2015

Purpose: To explore the association between sleep and the risk of accidental injury at school among Korean adolescents. Methods: From the database of the Ninth Korea Youth Risk Behavior Web-based Survey (KYRBS), the researcher selected 63,307 adolescents who responded to a survey on sleep hours. We conducted logistic regression with sleep duration and fatigue after sleep as independent variables, the risk of injury at school as a dependent variable, and gender, grade, school type, economic status, parents' education level, number of participations in physical education, and current smoking and drinking as control variables. Results: Using 9 hours of sleep as the reference, the adjusted injury risk (odds ratio) was 1.74 for those sleeping less than 5 hours a day, 1.61 for 5 hours, 1.45 for 6 hours, 1.31 for 7 hours, 1.13 for 8 hours, and 1.40 for 10 hours or longer. The difference between each pair of groups was statistically significant. In this study, injury risk increased as sleep duration decreased and fatigue after sleep increased. Conclusion: The findings suggest that a short nightly duration of sleep and fatigue after sleep can be considered potential risk factorsfor unintentional injuries at school among Korean adolescents.

• Journal of Korean Academy of Nursing
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• v.31 no.1
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• pp.126-138
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• 2001

The purpose of this study is to act nursing intervention strategies to promote quality of life (QOL) in Spinal Cord Injury patients. Therefore, the study is designed to evaluate religion, marital status, educational background economic status, level of injury, voiding pattern, transportation by driving, rehabilitation education, self-concept, sexual status, perceived barrier, powerlessness, depression, hope, social support, self-efficacy, anxiety, ADL, perceived hopelessness, personality and pain for QOL at the same time. It was gathered empirical data was collected using a self report questionnaire from 61 patients during a six month period after SCI at 5 general hospitals, at 2 rehabilitation centers and at 2 rehabilitation schools province from Jun. 18, 1999 through Sep. 28, 1999. The reliability of the 19 instruments was tested with Cronbach's alpha which ranged from .6319 to .9769. For the data analysis a SAS program was used for Pearson correlation coefficients, and stepwise multiple regression. The results were as follows; 1. The mean of total item score in the QOL scale was 2.814, which showed a much lower score than the cancer points. 2. There was a significant correlation between self concept, transportation by driving, perceived barrier, powerlessness, depression, hope, social support, self-efficacy, anxiety, ADL and QOL.(${\gamma}$= .27~-.79, p< .05) 3. Stepwise multiple regression analysis showed that; a) Depression was the main predictor of QOL and account for 53.7% of the variance in QOL. b) Hope, ecomic status and body satisfaction accounted for 8%, 4%, 3.4% respectively and these variables combined accounted for 69.2% of the variance in QOL. In conclusion, to begin with, it is important to reduce depression and to help for SCI points to inspire hope, economic status and body satisfaction. That will be short cut for nursing strategies to enhance QOL.

• Korean journal of applied entomology
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• v.50 no.4
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• pp.289-293
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• 2011

This study was conducted to develop economic injury level (EIL) of onion thrips, Thrips tabaci, on welsh onion (Allium fistulosum L. var) in the early transplanting stage. The changes of welsh onion biomass, yield loss, and T. tabaci density were investigated according to the inoculation periods of T. tabaci. In the early transplanting stage of welsh onion, the yield loss (%) increased with increasing inoculation periods: 17.0, 53.3, 38.4, and 80.8% yield loss in 5, 10, 15, and 20 d inoculation periods, respectively. The relationship between Cumulative Insect Days (CID) of T. tabaci and yield loss (%) of welsh onion was well described by a nonlinear logistic equation. Using the estimated equation, EIL of T. tabaci on welsh onion was estimated to 30 CID per plant based on the yield loss 12% (an empirical gain threshold 5% + marketable rate 93% of welsh onion). ET was calculated to 24 CID, which corresponds to 80% of EIL. Until a more defined EIL-model is developed, the present results should be useful for T. tabaci management in early growth stage of welsh onion. The effect of T. tabaci attack on the yield of welsh onion in late growing season (120 days after transplanting) was also examined. The yield of welsh onion increased at a low population density of T. tabaci and decreased at higher densities, showing a typical over-compensatory response.

• Physical Therapy Korea
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• v.12 no.4
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• pp.48-57
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• 2005

The purpose of this study was to evaluate the general characteristics, complications and level of social adaptation of spinal cord injured patients. The subjects were one hundred forty five members who were inpatients or outpatients from October 1, 2004 to April 30, 2005 in general hospitals and municipal welfare centers for the handicapped located in the metropolitan city of Gwangju. The following results were obtained using Modified Barthel Index (MBI). 1) Gender distribution was 77.9% male and 22.1% female. The mean age at the time of injury was 35.4 and the mean age during the study was 44.2. 2) The degree of paralysis among the subjects was as follows: 49.0% had complete paralysis and 51.0% suffered incomplete paralysis. The most frequently injured lesion among the subjects was cervical (49.0%), followed by thoracic (35.9%), and lumbar (15.2%). 3) The mean MBI score was 63.5. There was statistically significant difference in the MBI score in the relation between complete and incomplete paralysis, the relation between cervical, thoracic, and lumbar injury, and the relation between a recovery period of less than three years and more than three years according to the characteristics of injury (p<.05). 4) There was statistically significant difference in the MBI score of subjects who had complications concerning spasticity, deformity, urinary tract infection, and sexual dysfunction (p<.05). 5) The most serious emotional pain after spinal cord injury resulted from economic issues, which affected 35.2% of the subjects. The group having a shorter recovery period after spinal cord injury complained of psychological matters, the group having a longer recovery period complained about the surrounding environment (lack of convenient facilities), suggesting statistically significant difference (p<.05). 6) The most common activities of the group with injuries more than ten years old included meeting schoolmates and working, while most common activities of the group with injuries less than three years old included attending religious functions and miscellaneous others (watching TV, spending time with family), suggesting statistically significant difference (p<.05).

• Research in Plant Disease
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• v.12 no.3
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• pp.231-234
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• 2006

The influences of powdery mildew caused by Sphaerotheca fusca were assessed on cucumber to verify the economic injury level and yield response. Based on the relation of disease severity and yield response, economic threshold was determined by grading the disease severity of powdery mildew. Yield loss simulation due to damage of powdery mildew was conducted by defoliation of lower cucumber leaves in two seasons. The minimum number of leaves was 10 in spring season and 13 in autumn season which made no distinct difference on cucumber yield. The whole yields of cucumber was reduced as the disease severity was increased. Therefore occurrence of powdery mildew have a negative effect on cucumber yield. The regression equation between disease severity and yield loss showed Y=-57.237x+6143.1, $R^2=0.9628$. This equation suggests the disease severity of economic threshold is 17.6%, which is 3% reduction point of yield based on yield and economic relations. These results suggest that application of fungicide should be needed when 1 or 2 leaves of cucumber are infected by powdery mildew in the growing season.