• Journal of Korea Water Resources Association
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• v.40 no.2 s.175
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• pp.101-112
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• 2007

In this study, a methodology was developed to evaluate the effects produced in the event of joint-operation of dams from the viewpoint of water use. It was applied to evaluating the actual results of dam operation in the Han River basin. In order to evaluate the effects of real joint-operation in terms of water supply and flow conditions, the methodology used the satisfaction rate of water requirement and the stability of flow conditions at the evaluation site as indicator. In order to evaluate the effects of joint-operation in terms of power generation, the total power generation produced by dams was used as evaluation indicator. Actual operation results were evaluated by comparison of evaluation indicators relating to single dam operation by which the notified mont of water was supplied, as well as to optimization models. Results of actual joint-operation of the Han River basin, from 2001 to 2004, were compared yearly with results from single operation and optimization model; in terms of water supply, the satisfaction ratio of water requirement stood at $94.36{\sim}99.68%$ for single operation, $97.16{\sim}99.90%$ for actual joint-operation, and 100.0 % for optimization model for all four years. The stability of flow condition was evaluated by the coefficient of river regime and coefficient of flow conditions definitely, indicating that flow conditions were more stable in case of actual operation and optimization models than in case of single operation. The actual total power generation was compared with that generated by other operation rules, indicating that the optimization model increased the power generation by $-3.47{\sim}6.54%$ compared with the actual total power generation, and that the single operation decreased the power generation amount by $12.68{\sim}38.94%$ compared with the actual total power generation.

• 재활복지
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• v.22 no.3
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• pp.225-257
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• 2018

The purpose of this study is to find the application point of hearing augmentation technology development through examining the risk context experience of people with hearing impairment and the use of assistive device used as an alternative technology. Data of 355 people with hearing impairment with official disability grading was analyzed. The results of this study are first, research participants had no experience of recognizing any sound or vibration in situations highest in the order of means of transportation, material, and nature. Especially the ratio of being unable to recognize the sound and vibration of means of transportation was high, which implies the high possibility of people with hearing impairment experiencing risk. Secondly, the risk context that people with hearing impairment will most likely to experience are highest in the order of traffic accident, pedestrian accident, and daily life at home. Thirdly, the recognition of 2G phone/smart phone, vibrating digital alarm clock, light bar, vibrating wrist watch as assistive device for risk context awareness and notification was high and the satisfaction level of 2G phone/smart phone was the highest. Fourthly, the research participants had high recognition of assistive device for communication in the order of hearing aid, smart phone, videophone, cochlear implant and 2G phone and it was found that the satisfaction level and communication improvement level was the highest using the smart phone. Lastly, for the development of hearing augmentation technology the research participants recognized the importance of portable/wear convenience, price, and motion accuracy and for notification delivery means they preferred the method of using sight(text and light). Based on the results of this study policy and practical plans for hearing augmentation technology development for people with hearing impairment in risk context are proposed.

• Anxiety and mood
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• v.15 no.2
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• pp.115-121
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• 2019

Objective : The purpose of this study was to investigate prevalence of psychiatric symptoms and determine predictors of emotional distress of military hospital surgical patients. Methods : This study examined 104 orthopedic patients admitted to the Armed Forces Military Hospital September-November 2018. For the study, every subject completed self-assessment inventories regarding depressive and anxiety symptoms (Hospital Anxiety and Depression Scale), sleep problems (Pittsburgh Sleep Quality Index), problematic alcohol and tobacco use (Cut off, Annoyed, Guilty, Eye-opener screening), and psychiatric history. We performed the Student's t-test and the chi-square test for the collected data to investigate the prevalence of psychiatric symptoms, including emotional distress. Logistic regression analysis was used to examine the risk factors related to emotional distress of hospitalized military personnel. Results : There were no significant differences in socio-demographic and psychiatric symptoms between soldiers and officers. The prevalence of depressive and/or anxiety symptoms (emotional distress) was 21.2% (n=21). In the logistic regression analysis, psychiatric history [Adjusted Odds Ratio (AOR)=18.99 ; 95% Confidence Interval (CI)=1.42-253.57 ; p=0.026] and low military life satisfaction (AOR=15.67; 95% CI=1.46-168.11 ; p=0.023) correlated with emotional distress. Conclusion : Soldiers admitted to the military hospital showed similar prevalence of emotional distress as those at general hospitals. Considering military circumstances, it is necessary to detect and intervene regarding soldiers with a psychiatric history and low military life satisfaction to promote mental health at military hospitals.

• Archives of design research
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• v.20 no.3 s.71
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• pp.141-150
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• 2007

This study began with the question: "what influence would the width of river surface have on visual preference, provided that the environment surrounding the river does not change?" to evaluate the visual preference factors of the river scenery which could vary according to the change of water level. To estimate the minimum flow needed for river sceneries, field survey of Youngsan river was carried out to collect the field data and evaluated the visual preference factors to obtain a most preferred W/B ratio. At Youngsan bridge location, the feeling of open space factors, physical characteristic factors and complexity factors appeared to have significant relations to visual preferences. At Imgok bridge location, complexity factors, aesthetic factors and physical characteristic factors have significance to visual preferences. As a result of multi regression modeling, it was found that physical factors affected visual preferences the most at urban river locations and complexity factors affected the most visual preferences at rural river locations. As a results of this study, the most preferred W/B ratio was estimated as which vary from 0.5 to 0.7 and this results can contribute to the field of river landscape design to maximize the users' satisfaction level.

• Applied Chemistry for Engineering
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• v.29 no.5
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• pp.503-509
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• 2018

In this study, we used the ultrasonic extraction process as a method to extract antioxidant substances from kudzu, and measured the content of iso-flavonoids puerarin, daidzein, daidzin contained in kudzu. The response surface methodology which is a statistical analysis method for optimizing the extraction amount of iso-flavonoids from the kudzu and the process condition for maximizing the yield was applied. It is the final objective of this study to effectively derive the condition of the process that matches the target response with a minimum number of experiments and analyze the effect of each process condition on the response. In the response surface methodology, the central composite design was applied and the optimum condition was analyzed, and the three independent variables were set to ultrasonic irradiation time, volume ratio of ethanol/ultrapure water, ultrasonic irradiation power. Using the response surface methodology, the optimum conditions with the maximum extraction yield and the content of iso-flavonoids were evaluated as ultrasonic irradiation time (24.75 min), ethanol / ultrapure water volume ratio (39.75 vol%), ultrasonic irradiation power (592.36 W). The overall satisfaction level appears as high as 0.8938, which is recognized at a significance level within 5%. As a result of analyzing the optimization process, it was confirmed that the ultrasonic irradiation time is the factor that most affects the responses.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.599-611
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• 2012

The purpose of this study was to investigate the effect of food behavior on dietary food intake status and health condition based on research of food behavior and nutritional intake status of university students in the Chungnam area. The average age, height, and weight of the subject group were 22.1 years old, 174.2 cm, and 67.0 kg for the male students and 20.9 years old, 161.8 cm, and 53.4 kg for the female students, respectively. From the nutritional intake status data, the averaged daily energy intake of both groups, male and female, are lower than the dietary reference intake(KDRI), as 2,169.2 kcal and 1,846.2 kcal, males and females, respectively. The lipid intake ratio was higher than the dietary reference figure, and the carbohydrate intake ratio was determined to be in the proper range. Male students(54.6%) and female students(52.0%) of the entire subject group skipped a breakfast mainly due to insufficient time, and the time at which meals were consumed, was determined to be irregular generally. In a day, male and female students have a heavier dinner than lunch(p<0.05), respectively. Meat and fishes are preferred by the entire subject group, and the number of students, who do not eat carrot and mayonnaise(p<0.05), was determined to be the highest, of all foods surveyed. The averaged daily activity coefficient and the resting energy expenditure shows significant difference(p<0.001) between two groups; was 1.7 and 1.6 and the second was 1,404.3 kcal/day and 1,292.5 kcal/day for the male and female groups, respectively. As the number of attempting to reduce body weight(p<0.001), the amount smoking(p<0.001), or the frequency of drinking alcohol increases, BMI decreases. On the other hand, as body shape satisfaction increases, BMI increases also.

• Applied Chemistry for Engineering
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• v.32 no.2
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• pp.168-173
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• 2021

In this study, we measured total flavonoids after extracting the total flavonoids from lemongrass which is known to have a high content of antioxidant ingredients when using microwave energy. Also, optimal extraction conditions of active ingredients using central composite design-response surface methodology (CCD-RSM) were presented. Both ultrapure water and alcohol were used as extraction solvents and the volume ratio of ethanol/ultrapure water, microwave irradiation time, and microwave irradiation power were set as independence variables. And the extraction yield and total flavonoids were measured. The optimal extraction conditions using CCD-RSM were the volume ratio of ethanol/ultrapure water = 56.3 vol.%, the microwave irradiation time = 6.1 min, and the microwave irradiation power = 574.6 W. We could also obtain expected results of yield = 17.2 wt.% and total flavonoids = 44.7 ㎍ QE/mL dw under the optimum conditions. The comprehensive satisfaction degree of this formula was 0.8562. The P-value was calculated for the yield of 0.037 and the total flavonoids content of 0.002. The average error from actual experiments established for the verification of conclusions was lower than 2.5%. Therefore, a high favorable level could be obtained when the CCD-RSM was applied to the optimization of extraction process.

• Journal of Korea Society of Industrial Information Systems
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• v.25 no.6
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• pp.47-54
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• 2020

The acupressure is a treatment that applies pressure to certain parts of the body and has been mainly used for pain relief in the field of oriental medicine. However, the treatment effect is often different depending on the practitioner's ability, experience, and physical strength, so standardized acupressure is needed. In this regard, the equipment is being released, but this is mainly a rolling massage method, which reduces energy concentration and poses a risk of injury. Therefore, in this study, a device that provides vertical acupressure based on variable bogie (wheel truck) was implemented. As a result of experimenting with load and body pressure distribution and desirability to validate the device's bearing pressure, the acupressure rod held up to 150kg, the body pressure ratio was measured lower than the body pressure ratio of the comparison item in section 0%

• Journal of People, Plants, and Environment
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• v.24 no.4
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• pp.311-327
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• 2021

Background and objective: Recent urban agriculture meets the needs of urban residents that safety and avoids using chemical pesticides. This study was conducted to identify various factors of companion planting affecting the growth of cherry tomatoes, which will promoting urban agriculture by improving socioeconomic satisfaction with gardening activities through quality. Methods: Four types of companion plants such as marigold, zinnia, spearmint and basil, that have a companion effect with growth, sugar content, and vitamin C content. We obtained the mean and standard deviation and tested the significance at a 95% confidence level (p < .05) with Duncan's multiple range test after one way ANOVA and MANOVA. Results: Compared to monoculture of cherry tomatoes, the plant growth in the treatment plots with companion planting showed a significant increase overall(p < .05), but there wasn't interaction effect among companion plants, planting ratio and type. As for the absorption of inorganic components, the companion planting showed better absorption than monoculture of cherry tomatoes, as favorable growth, and there was an interaction effect among the individual factors. The sugar content was higher than the standard sugar content of 5.8 brix in both the treatment plots at the control, and vitamin C content was higher than the control at 26.27mg/100g in all treatment plots, but there wasn't statistically significant difference. The soil pH in the cultivation plot ranges from 5.5 to 9.0 and was weakly alkaline in all treatment plots except zinnia, showing low contents of phosphoric acid, exchageable potassium, calcium and magnesium. Conclusion: This study was conducted to analyze various factors such as the growth of cherry tomatoes, contents of inorganic components, sugar content and vitamin C content of fruits, and soil analysis according to companion plants, planting type, and planting ratio. We will study sugar content by measuring the change in growth every phase of fruits.

• Journal of Digital Convergence
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• v.12 no.9
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• pp.93-99
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• 2014

This study aims to explore and analyze smartphone users' characteristics from the two perspectives (purchase vs. use characteristics) on the two operating systems (iOS and Android). The results of the study on purchase characteristics show that smartphones choice priority and the gender ratio are found to be significantly different between the two operating system users. However, the replacement cycle is not statistically different from iOS and Android users. The results of study on use characteristics show that the number of the applications and the registered SNS(social network service), the average monthly smartphone bill, and satisfaction are significantly different between iOS and Android users. However, the average Internet usage time is not different between the two operating system users. The findings provide useful implications for operating developers, smartphone manufacturers, and application developers.