• Journal of Korea Water Resources Association
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• v.50 no.7
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• pp.503-511
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• 2017

In order to estimate the demand for water resources planning and operation, methodology for determining the size of water supply facilities has been mainly applied to agricultural water, unlike living and industrial water, which reflects actual usage trends. This inevitably leads to an overestimation of agricultural water and can lead to an imbalance in the supply and demand of each use in terms of the total water resources plan. In this study, the difference of approaches of concept of net consumption was examined in comparison with the existing methodology and the characteristics of agricultural water demand were analyzed by applying it to whole Jeju Island. SWAT model was applied to estimate the amount of evapotranspiration, which is a key factor in estimating demand, and watershed modeling was performed to reflect geographical features, weather, runoff and water use characteristics of Jeju Island. For the past period (1992~2013), demand of Jeju Island as a whole was analyzed as 427 mm per year, and it showed a relatively high demand around the eastern and western coastal regions. Annual demand and seasonal variation characteristics of 10 river basins with watershed area of $30km^2$ or more were also analyzed. In addition, by applying the cultivated area of each crop in 2020 in the future, it is estimated that the demand corresponding to the 10-year frequency drought is 54% of the amount demanded in the previous research. This is due to the difference in approach depending on the purpose of the demand calculation. From the viewpoint of water resource management and operation, additional demand is expected as much as the net consumption. However, from the actual supply perspective, it can be judged that a facility plan that meets the existing demand amount is necessary. In order to utilize the methodologies and results presented in this study in practice, it is necessary to make a reasonable discussion in terms of policy and institutional as well as engineering verification.

• Korean Journal of Ecology and Environment
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• v.39 no.1 s.115
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• pp.110-118
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• 2006

The Namyang Stream in Hwaong polder was planned for several water uses including recreation, where people can contact the water and consume some amount during the recreational activity. A human health risk was assessed from exposure to E. coli in the Namyang Stream, which receives partially treated wastewater from watershed. The QUAL2E model was applied to simulate stream water quality, and this model was calibrated and verified with field monitoring data. The calibration result showed a high correlation coefficient of greater than 0.9. The mean concentration of E. coli in the Namyang Stream from the QUAL2E output was in the range of 5,000 ${\sim}$ 8,000 MPN 100 mL^{-1}$, which exceeded national and international guidelines. The Beta-Poisson was used to estimate the microbial risk of pathogens ingestion and the Monte-Carlo analysis (10,000 trials) was used to estimate the risk characterization of uncertainty. The Microbial risk assessment showed that the risk ranged from 7.9 ${\times}\;10^{-6}\;to\;9.4\;{\times}10^{-6}$. Based on USEPA guidelines, the range of $10^{-6}\;to\;10^{-8}$ was considered reasonable levels of risk for communicable disease transmission from environmental exposure, and the risk above $10^{-4}$ was considered to be in the danger of infection. Therefore, water quality of the Namyang Stream might not be in the danger of infection although it exceeded national and international guidelines. However, it was in the range of communicable disease transmission, and thorough wastewater collection and treatment at the source is recommended to secure safe recreation water quality.

• Journal of the Korean Institute of Gas
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• v.5 no.4 s.16
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• pp.1-7
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• 2001

This paper presents a 'consequence analysis' for vapor cloud explosions caused by heavy gas leakages from commercially used storage tanks at petrochemical plants. Particularly, this paper emphasizes on evaluating the results of various vapor cloud explosion accidents from Butane storage tanks. Also this paper analyses the impact of variables on the accidents in order to acquire the optimum conditions for variables. $SuperChems^{TM}$ Professional Edition was applied to analyse the impact (If atmospheric and other variables in the situation where vapor cloud continuously disperses from the ground level. Under the assumption that practical operating conditions are selected as a standard condition, and Butane leaks from the storage tank for 15 minutes, the results show that the maximum distance of LFL (Lower Flammable Limit) was 52 meters and overpressure by the vapor cloud explosion was 1 psi at 128.2 meters. It is observed that the impact of the variables on accidental Butane storage tank leakage mainly varied upon atmospheric stability, wind velocity, pipe line size, visible length, etc., and changes in the simulation result occurred as the variables varied. The maximum distance of the LFL (Lower Flammable Limit) increased as the visible length became shorter, the size of the leak became larger, the wind velocity was decreased, and the climatic conditions became more stable. Thus, by analysing the variables that influence the simulation results of explosions of Butane storage tanks containing heavy gases, I am presenting the most appropriate method for 'consequence analysis' and the selection of standards for suitable values of variables, to obtain the most optimal conditions for the best results.

• Journal of Nutrition and Health
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• v.53 no.2
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• pp.190-202
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• 2020

Purpose: This study aims to evaluate the recognition, purchase, and intake status of edible insects in adults, who are the main consumers of edible insects, and to provide the information necessary to expand the production and consumption of edible insects and related products in the future. Methods: A total of 453 adults (172 males and 281 females) aged 19 years and older were surveyed regarding their awareness of edible insects, purchase and consumption experience, and intention to purchase and consume, and the differences between them were analyzed according to gender and age groups. Data collection took place from December 2018 to January 2019. Results: Those who had knowledge of edible insects accounted for 87.0%, whereas those who had more than average knowledge were 75.9%, suggesting recognition was relatively high. Men had more experience than women in purchasing or consuming edible insects and related products (45.9% vs. 31.0%, p < 0.01). In terms of age, experience was 22.5% in 20-30s, 44.6% in 40-50s, and 63.1% in 60s and older, showing significant growth as age increased (p < 0.001). The satisfaction level of edible insects was highest in taste (3.4 points), and especially for shape and appearance, it decreased as age reduced (p < 0.001). The most common reason for not being willing to use edible insects was feeling repulsive (4.1 points), which was significantly more common in women than in men (4.3 vs. 3.9, p < 0.001), and lower with age (p < 0.001). The most needed information display for using edible insects was country of origin (63.8%), the main nutrient in edible insects was protein (93.6%), and the most preferred form of products was powder (39.5%). Conclusion: According to the above results, the recognition of edible insects was high, whereas experience of using edible insects and intention to use edible insects were low especially in women and younger groups. The reason for this is that consumers are dissatisfied with edible insects due to their appearance. This study is expected to be used as basic data for expanding the production and consumption of edible insects and related products in the future.

• Korean Security Journal
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• no.13
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• pp.471-485
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• 2007

This study is performed to find out what type instructions are produced to players by coaches and what effects are resulted in cooperative spirit of the concerned group. Furthermore the study has its aims at advancing instructors' skills by using finding of it. The study used 'SPSS 11.0 FOR WINDOW - Statistical Package' to analyze the collected samples and dealt with data of 174 individuals. Statistical analysis of the research for hypothesis verification was about frequency, trust level, mutual relationship, variables, and T-verification. The meaningful level for any result was ranged within 95%(p< .05), 99%(p<.01). The finding are as follows. Effects on pleasure, one of elements of team spirits taken by instructor's training style are analyzed as follows. It was proved to be meaningful in relation with a series of activities like training, democratic, social, compensatory aspects and showed also considerable relation with power based behaviors. That says, players are found to enjoy high pleasure when social and bureaucratic behaviors of instructors are very energetic. In addition to that, training, democratic, and compensatory activities didn't show any meaningful effect. Team spirit was found to play a main role between instructor's behaviors and training, democratic, social rewarding activities. Democratic and social acts influence on team spirit. Looking into the detailed aspects, team spirit was resulted very high in the individuals with low democratic mind and was shown high group spirit by groups with high sociable activities. Teamworks was found to be affected by relation between instructor's acts and training, democratic, social and compensatory aspects and it showed meaningful relations with training, social, bureaucratic behaviors. Low degree of training and bureaucratic activities are found to prefer for power team spirit, and high social activities led a strong teamworks. Group binding spirit was influenced by training, democratic, social compensatory, bureaucratic behaviors and it showed to give effects on democratic, social, and bureaucratic activities of instructors. Low degree of democratic and bureaucratic behaviors are found to produce strong team spirit. In contrast with that, strong social activities was found to be motive of powerful team spirit. Value of team spirit was found to play a main role between instructor's behaviors and training, democratic, social, rewarding activities. It didn't show any meaningful effect on behavior of instructors.

• Journal of Preventive Medicine and Public Health
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• v.29 no.3 s.54
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• pp.669-678
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• 1996

Helicobacter pylori is now recognized as causative agent of chronic gastritis and peptic ulcer, and strongly associated with development of gastric carcinoma. With development of sensitive and specific serologic tests to identify individuals infected with Helicobacter pylori, the epidemiologic study of this diseases has been investigated. But it's transmission route is not established, yet. The purpose of this study is to measure the prevalence of Helicobacter pylori infection in healthy children and young adults and to evaluate related factors for Helicobacter pylori infection in Korea. The seroprevalence of Ig G antibodies to Helicobacter pylori was determined using a Enzyme Linked Immunosorbent Assay and we obtained the information, such as demographic characteristics, monthly household income, numbers of family members in the house, numbers of persons using same room, type of house, and type of drinking water through the questionnaire survey. The observed overall seropositivity rate was 25.7%. The rate is increased progressively from 5.8% in the age group $1\sim3$ years to 44.4% in the age group $20\sim29$years($\chi^2$ for trend, p<0.001). Especially, the rate increased steeply from 6.5% in the age group $4\sim6$ years to 20.8% in the age group $7\sim9$ years, and this suggested that elementary school age was the major acquisition time of Helicobacter pylori infection. In multivariate logistic regression model, age, numbers of family members in the house, and type of house was statistically significant variables for Helicobacter pylori infection. Each odds ratio(93% CI) were as follows; base to age group $1\sim9$ years, age group $10\sim19$ years $3.6(2.0\sim6.4)$, age group $20\sim29$ years $7.3(4.1\sim13.1)$ and base to group of $1\sim3$ family members, group of $4\sim5$ family members $2.1(1.1\sim4.0)$, group of 6 or more family members $2.7(1.3\sim5.4)$ and base to apartment, single and multihouse $1.9(1.1\sim3.5)$. Sex, monthly household income, numbers of persons using same room, and type of drinking water was not statistically significant for Helicobacter pylori infection.

• Journal of Preventive Medicine and Public Health
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• v.29 no.3 s.54
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• pp.539-553
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• 1996

The study was conducted from May to September in 1994 to investigate applicability of the Hearing Handicap Inventory for the Elderly-Screening version(HHIE-S) in parallel with the pure-tone audiometer to the initial screening test of noise-induced hearing loss(NIHL) in some noise-exposed workers. Subjects were selected by systemic sampling that took every 10th person from 6, 700 workers taking the annual occupational health examination by the department of Health Maintenance of Dongsan Hospital Keimyung University in Taegu. The authors administered the pure-tone audiometric test and self-reported questionnaire of HHIE-S including items of sociodemographic and job-related variables concurrently. The final subjects analysed were 1,019(488 males and 531 females) excluding fourteen persons who had many missing values in their questionnaires. The reliability coefficients of HHIE-S scale by Cronbach's alpha were 0.84. In the univariate analysis of hearing handicap measured by the HHIE-S, work duration, military service and the hearing threshold loss at 1KHz and 4KHz by the initial audiometer were significant in males while age, work duration and hearing threshold loss at 1KHz and 4KHz were significant in females. In the stepwise linear regression analysis, hearing threshold loss at 1KHz and 4KHz, was the only selected variable explaining the hearing handicap in males and hearing threshold loss at 1KHz and 4KHz, age, and work duration were selected in females. In ROC curves for HHIE-S scores against NIHL as gold standard which was defined by the follow-up audiogram as more than 30dB of the average of 0.5/1/2KHz and 50dB at 4KHz, the optimal cutoff for the parallel HHIE-S appeared to be 8. The results suggest that HHIE-S appeared to have some reliability and validity in this data and might be used in screening NIHL in parallel with pure-tone audiometer in noise-exposed workers.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.3
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• pp.163-172
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• 1989

In order to study spatial variability of soil physical properties accross the land-partitioned boundary on Hwadong silt clay loam soil (Fine clayey, mixed, mesic family of Aquic Hapludalfs), all measured data were analyzed by means of kriging, fractile diagram, smooth frequency distribution, and autocorrelation. Sampling for soil particle size distribution analysis was made at 225 intersections of $15{\times}15$ grid with 10m interval. Field capacity, bulk density and saturated hydraulic conductivity were measured in situ at 594 intersections of $33{\times}18$ grid with 2.5m interval in only $6,000m^2$ reselected from $22,500m^2$ of sampling area for particle size distribution analysis. Sampled or measured soil depths were 0 to 10cm 25 to 35cm and 50 to 60cm at each intersections. The results are summarized as follows: 1. The coefficient of variance (CV) of various physical properties ranges from 4.8 to 128.8%. Saturated hydraulic conductivity is classified into the high variation group with CV greater than 100%, while the low variation group with CV smaller than 10% consists of bulk density. Other properties belong to the medium variation group with CV between 10 and 100%. 2. The appropriate number of soil samples for the determination of various physical properties with error smaller than 10% are calculated as one for bulk density, six for field moisture capacity, 16 for silt, 19 for clay, 69 for sand and 686 for saturated hydraulic conductivity. 3. Smooth frequency distribution and fractile diagram show that saturated hydraulic conductivity is in lognormal distribution while other physical properties are in normal distribution. 4. Serial correlation analysis reveals that the soil physical properties have spatial dependence between two nearest neighbouring grid points. Autocorrelation analysis of physical properties measured between the serial grid points in the direction of south to north following section boundary shows that the zone of influence showing stationarity ranges from 7.5 to 40m. In the direction of east to west across section boundary, the autocorrelogram of many physical properties shows peaks with the periodic interval of 30m, which are similar to the partitioned land width. This reveals that the land-partitioned boundary causes soil variability.

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.4
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• pp.322-331
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• 2016

Oil budget calculator identifies the removal pathways of spilled oil by both natural and response methods, and estimates the remaining oil required response activities. A oil budget calculator was newly developed as a response tool for Deepwater Horizon oil spill incident in Gulf of Mexico in 2010 to inform clean up decisions for Incident Comment System, which was also successfully utilized to media and general public promotion of oil spill response activities. This study analyzed the theoretical background of the oil budget calculator and explored its future application to Korea. The oil budge calculation of four catastrophic marine pollution incidents indicates that 3~8% of spilled oil was removed mechanically by skimmers, 1~5% by in-situ burning, 4.8~16% by chemical dispersion due to dispersant operation, and 37~56% by weathering processes such as evaporation, dissolution, and natural dispersion. The results show that in-situ burning and chemical dispersion effectively remove spilled oil more than the mechanical removal by skimming, and natural weathering processes are also very effective to remove spilled oil. To apply the oil budget calculator in Korea, its parameters need to be optimized in response to the seasonal characteristics of marine environment, the characteristics of spilled oil and response technologies. A new algorithm also needs to be developed to estimate the oil budget due to shoreline cleanup activities. An oil budget calculator optimized in Korea can play a critical role in informing decisions for oil spill response activities and communicating spill prevention and response activities with the media and general public.

• The Journal of Korean Society for Radiation Therapy
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• v.25 no.1
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• pp.77-85
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• 2013

Purpose: The accurate movement of gantry rotation, collimator and correct application of dose rate are very important to approach the successful performance of Volumetric Modulated Arc Therapy (VMAT), because it is tightly interlocked with a complex treatment plan. The interruption and restart of dose delivery, however, are able to occur on treatment by various factors of a treatment machine and treatment plan. If unexpected problems of a treat machine or a patient interrupt the VMAT, the movement of treatment machine for delivering the remaining dose will be restarted at the start point. In this investigation, We would like to know the effect of interruptions and restart regarding dose delivery at VMAT. Materials and Methods: Treatment plans of 10 patients who had been treated at our center were used to measure and compare the dose distribution of each VMAT after converting to a form of digital image and communications in Medicine (DICOM) with treatment planning system (Eclipse V 10.0, Varian, USA). We selected the 6 MV photon energy of Trilogy (Varian, USA) and used OmniPro I'mRT system (V 1.7b, IBA dosimetry, Germany) to analyze the data that were acquired through this measurement with two types of interruptions four times for each case. The door interlock and the beam-off were used to stop and then to restart the dose delivery of VMAT. The gamma index in OmniPro I'mRT system and T-test in Microsoft Excel 2007 were used to evaluate the result of this investigation. Results: The deviations of average gamma index in cases with door interlock, beam-off and without interruption on VMAT are 0.141, 0.128 and 0.1. The standard deviations of acquired gamma values are 0.099, 0.091, 0.071 and The maximum gamma value in each case is 0.413, 0.379, 0.286, respectively. This analysis has a 95-percent confidence level and the P-value of T-test is under 0.05. Gamma pass rate (3%, 3 mm) is acceptable in all of measurements. Conclusion: As a result, We could make sure that the interruption of this investgation are not enough to seriously affect dose delivery of VMAT by analyzing the measured data. But this investigation did not reflect all cases about interruptions and errors regarding the movement of a gantry rotation, collimator and patient So, We should continuously maintain a treatment machine and program to deliver the accurate dose when we perform the VMAT for the many kinds of cancer patients.