• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.103-103
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• 2015

유류유출사고와 같이 하천 수표면의 흐름에 따라 이동 확산하는 부유성 오염물질의 혼합해석을 위해 많은 연구자들은 입자추적모형을 사용한 혼합모의를 수행해왔다. 입자추적모형에서 오염물질의 혼합은 평균 유속 분포에 의한 결정론적인 이동과 난류유동에 의한 무작위적인 혼합으로 나타내며, 난류혼합에 의한 수평확산은 난류확산계수로 조절한다. 따라서 표면흐름에 의한 난류확산계수의 산정을 위해 많은 연구자들은 부유성 입자를 이용한 실내실험을 수행하여 수평확산계수를 산정했고(Engelund, 1969; Cederwall, 1971), 최근에는 GPS의 발전으로 인해 해양영역에서 GPS를 장착한 표면부자를 활용한 확산실험을 통해 수평확산계수를 산정한 바 있다(Kjellson and $D{\ddot{o}}{\ddot{o}}s$, 2012; Alpers 등, 2013). 하천수질오염사고의 약 43.5%가 유류유출에 의한 것이며(환경부, 2013), 이에 따라 표면흐름에 의한 오염물질 혼합해석이 필요하나, 하천에서 수평확산계수 산정을 위한 현장실험연구는 부족한 상황이다. 따라서 본 연구에서는 낙동강 본류에서 GPS부자를 이용한 입자추적실험을 수행하여 표면흐름에 의한 확산계수를 산정했다. GPS부자를 이용한 입자추적실험은 낙동강의 강정고령보 하류와 구미보 하류의 각각 세 지점에서 수행되었다. GPS부자는 바람에 의한 교란을 최소화하기 위해 지름 10 cm의 구형으로 제작하였으며 시범테스트를 통해 입자의 주 궤적 변화가 크지 않은 지점에 GPS부자를 투입했다. GPS부자는 오염물질의 사고유출을 가정하여 한 지점에 투입했고 GPS부자 사이의 간섭을 최소화하기 위해 25 ~ 35개의 GPS부자를 이용했다. 표면흐름에 의해 이동하는 부자의 위치는 GPS에 시계열로 저장됐고 ADCP를 이용하여 실험당시의 수리량을 측정했다. 입자위치의 시계열자료로부터 GPS부자의 확산범위의 시간변화를 계산했고 단순 모멘트법을 이용하여 종, 횡 방향 확산계수를 계산했다. 그 결과, 종 방향 확산계수는 $0.003{\sim}0.041m^2/s$로 계산되었고 횡 방향 확산 계수는 $0.001{\sim}0.012m^2/s$로 계산되어, 흐름방향의 유속성분에 의한 확산이 지배적인 것으로 나타났다. 지류 합류부에서는 이송이 지배적인 혼합이 발생되었고(Pe>1) Pe의 증가에 따라 수평확산계수가 감소되었다. 25~35개 GPS부자 궤적의 앙상블 평균으로부터 계산한 Integral time scale은 모멘트법으로부터 계산한 종, 횡 방향 확산계수와 비례하는 것으로 나타나, Taylor(1921)의 이론과 일치했다. 또한 실험수로에서 수행된 기존연구결과와 비교한 결과, 하폭 대 수심비, 마찰항의 증가에 따라 수평확산계수가 증가하는 경향을 나타내었다.

• Journal of the Korean Applied Science and Technology
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• v.38 no.4
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• pp.1070-1080
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• 2021

This study is a descriptive survey research on social network service addiction tendency and interpersonal relationships on college life adaptation among nursing students. The study period was from October 1 to 4, 2019, the survey was conducted for 228 first and third year nursing students located in G city. The collected data were analyzed with the SPSS 23.0 program using descriptive statistics, ANOVA, Pearson correlation coefficients, and multiple regression. The results of the study showed that there were differences in the subjects' college life adaptation depending on their gender (t=5.26, p<.001), daily average duration of using social network service (F=8.07, p<.001), and friends in real life (F=2.87, p=.037). College life adaptation had a significant correlation with social network service addiction tendency (r=-.31, p<.001) and interpersonal relationships (r=.52, p<.001), and social network service addiction tendency with interpersonal relationships had a significant correlation (r=-.17, p=.011). Factors that affected college life adaptation included interpersonal relationships (𝛽=.477, p<.001), gender (𝛽=-.198, p=.001), and daily average duration of using social network service (𝛽=-.177, p=.003), and the explanatory power of these factors was 37.8%. Based on the results of this study, it is thought that it is necessary to develop a program for a positive interpersonal relationship formation using social network service in order to improve the college life adaptation of nursing students.

• Journal of the Korea Convergence Society
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• v.12 no.7
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• pp.317-327
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• 2021

This study is a randomized controlled trial to compare the effects of light therapy on stress, depression, sleep quality and quality of life in middle-aged women. The participants of this study were 56 middle-aged women who worked at the same office. Data collection period was from August 26 to September 13 for the control group and from September 16 to October 4 for the experimental group. Subjective stress, depression, quality of sleep and quality of life in middle-aged women were measured by Numeric Rating Scale (NRS), Center for Epidemiology studies of scale (CES-D), Verran & Synder-Halpern Sleep scale (VHS) and WHO Quality of Life Scale Abbreviated Version (WHOQOL-BREF). Stress index was measured using a Canopy9 RSA (IEMBIO, Gangwondo, Korea) equipment. The data were analyzed by mean, standard deviation, real number and percentage, χ²-test, t-test, repeated measures ANOVA and ANCOVA using IBM SPSS Statistics version 25.0. The results showed that the experimental group applying light therapy had significantly lower subjective stress (F=6.30, p<.001) and higher quality of life (F=2.80, p=.049) than the control group, There was no difference in objective stress index, depression, and sleep quality. As a result, light therapy is partially effective in subjective stress and quality of life for middle-aged women, and further research is needed on middle-aged women working in work environments with limited light exposure.

• 한국노년학
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• v.38 no.4
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• pp.853-869
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• 2018

This study aimed to investigate variables affecting subjective memory impairment in the elderly with benign prostatic hyperplasia. We used 179 survey data collected from the urology department of two metropolitan general hospitals. The subjects were patients with benign prostatic hyperplasia. T-test, one-way analysis of variance, and $Scheff{\acute{e}}^{\prime}s$ test were performed to identify differences among variables. Pearson's correlation-coefficient and stepwise multiple regression were used to identify variables that affect subjective memory impairment. This study revealed that lower urinary tract symptom and activities of daily living were statistically significant variables, with an explanatory power of 30.0%. The lower urinary tract symptom was due to the benign prostatic hyperplasia increasing the risk of subjective memory impairment. Treatment of the lower urinary tract symptom was delayed because as the elderly got older, they increasingly recognized benign prostatic hyperplasia as a reasonable symptom. Timely intervention and early screening are necessary to prevent lower urinary tract symptom. Finally, programs to reduce the incidence of lower urinary tract symptom and educate nurses to assess, evaluate, perform intervention for subjective memory impairment should be developed.

• Journal of Mushroom
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• v.16 no.4
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• pp.299-303
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• 2018

Flammulina velutipes, which is a white rot fungus, is a commercially important edible mushroom and is produced in large quantities with the help of an automated and mechanized cultivation system in Korea. F. velutipes has the lowest distribution rate among domestic cultivars, estimated at about 20 percent. As most white cultivars of F. velutipes produced and exported to Korea were introduced from Japan, farmers pay large amounts of royalties. Therefore, we have developed a new, purely domestic cultivar, "Baeke," to substitute for Japanese cultivars, which has improved storage characteristics for export. Baeke was bred by mating two monokaryotic strains isolated from ASI 4216-18 (Hansol) and ASI 4217-26 (Baekjung). Baeke showed faster mycelial growth and higher mycelial density upon incubation for seven days at $25^{\circ}C$ on PDA media than the control variety. The mycelial growth of Baeke was even maintained at $30^{\circ}C$ unlike the control. The lengths of pilei and stipes in Baeke harvested in the optimal stage were $11.2{\pm}0.5mm$ and $125{\pm}5.4mm$, respectively, and they were $11{\pm}0.5mm$ and $141.9{\pm}5.7mm$, respectively, in the control harvested in the optimal stage. The yields of Baeke ($257.4{\pm}13.5g$) and control ($270.7{\pm}17.8g$) per 1,100ml in bottle cultivation showed no significant difference. Overall, our results showed that Baeke was at par with foreign varieties of Flammulina velutipes in terms of quality and yield and had a uniformly shaped fruitbody, which added to its commercial value.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.3
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• pp.49-59
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• 2019

This paper examines the background and content of Thomas Jefferson's botanical garden plan for the University of Virginia. When Jefferson promoted the establishment of a botanical garden, European botanical gardens were evolving from physic gardens, and American botanical gardens were in their infancy. Accordingly, this paper compares the Botanical Garden Plan for the University of Virginia with contemporary botanical gardens. This is examined by outlining the trends of botanical gardens in Europe and the United States around the nineteenth century, analyzing their function and spatial structure. Also, Jefferson's perspective on botany, his plan, and botanical gardens are reviewed. This study found that Jefferson's project had its background in the social recognition of the importance of botany as a practical science, advancing the national economy, which was a prominent goal in late eighteenth-century Europe, and in developing networks of exchanging plants and information concerning botany and botanical gardens. Based on the botanist Correia's opinion on the role of a public botanical garden, the Botanical Garden Plan for the University of Virginia was developed by Jefferson as an action plan, including its site creation, space organization, and supplying of plants. Compared to the other contemporary botanical gardens, the University of Virginia's Botanical Garden Plan has the following characteristics. First, like European gardens in the late eighteenth century, it evolved from being a physic garden to a botanical one. As such, it emphasized botanical research and education over medicine, creating a tree garden and a plant garden. Second, it differed from many European and American botanical gardens in that it rejected decorative elements, refused to install a greenhouse, and attempted to spread practical overseas plants suitable to the local climate. This study contributes to broadening the history of botanical gardens at the turn of the nineteenth century.

• Korean journal of applied entomology
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• v.58 no.3
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• pp.233-238
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• 2019

For greenhouse crops, thrips is one of the major insect pests, but its control is difficult owing to short generation time, rapid escaping behavior, and development of pesticide resistance. Stratiolaelaps scimitus (Womersley) is a soil-dwelling predatory mite attacking various soil invertebrate species, including thrips. Using the method by growers' self-production, we mass-reared S. scimitus colony and investigated thrips control in the greenhouse chrysanthemum. The initial density of thrips was six individuals/flower. The treatment with one S. scimitus box in the greenhouse was estimated to be $1,000individuals/m^2$. From August to September 2018, the greenhouse was released with a total of 10 boxes of S. scimitus. The density of thrips in the untreated and the treated cultivar was $53.7{\pm}7.0$ and $13.5{\pm}1.7$ on the late September, respectively, which indicated a reduction of 74.9% in the treated cultivar. Our results suggest that S. scimitus was highly effective for the control of thrips in the greenhouse chrysanthemum although temperature is very high during the summer season.

• Korean Journal of Organic Agriculture
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• v.26 no.4
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• pp.629-647
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• 2018

This study was carried out to investigate the economic value of organic rice production using gelatin chitin microorganisms in eco-friendly complex, Gongsan, Naju city. The soil condition of experiment paddy field was Jeonbuk series and silt loam with a slightly poor drainage. Except for the high effective silicate, the chemical characteristics of soils used were included in the optimum range of paddy soils in Korea. In growth, plant length, tiller number, ear number, and ear length were observed to be higher in conventional paddy fields than organic paddy fields. However, number of grain per panicle and grain filling ratio (%) were higher in organic paddy fields than conventional paddy fields. Incidences of diseases and insect pests were slightly higher in the organic paddy fields. Water weevil, sheath blight, rice leaf roller and rice blast were more occurred in organic paddy field. On the other hand, false smut was higher occurred in conventional paddy field. There was a significant negative correlation between rice sheath blight and rice leaf roller, and rice yield. In the milled rice quality, the quality of organically cultivated milled rices was lower by the increase of broken rice than that of conventionally cultivated milled rices. The quality and palatability of rice were higher in organic cultivation with decreasing of protein content. Net income of conventionally and organically cultivated rice was 360,000 won/10a and 610,000 won/10a, respectively. Premium net income of the organically cultivated rice was 68%.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.137-148
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• 2019

This study was conducted to investigate the factors influencing burnout of nurses in long-term care hospitals based on the expanded JD-R model (Xanthopoulou et al, 2007). Participants were 167 nurses who worked in long-term care hospitals. The instruments used in this study were the Maslach Burnout Inventory, Copenhagen Psycho-social Questionnaire version II, Connor-Davidson Resilience Scale and the instrument developed by Thomas and Ganster (1995). Data were collected from August 25 to September 6, 2018 and analyzed based on frequency, t-tests, ANOVA, Pearson's correlation, and hierarchical regression using the SPSS WIN 23.0 program. The results were as follows: Nurses' burnout in long-term care hospitals was positively correlated with job demands (r=.24, p=.002) and negatively correlated with resilience (r=-.43, p<.001) and social support (r=-.41, p<.001). Factors influencing the level of burnout were resilience (${\beta}=-.28$, p<.001), social support (${\beta}=-.20$, p=.016), and job demands (${\beta}=.17$, p=.016) ), which together explained 32.0% of the total variance in burnout. Therefore, we strongly recommend interventions that reduce job demands and enhance resilience and social support to prevent and reduce the burnout of nurses in long-term care hospitals.

• Mood & Emotion
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• v.16 no.3
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• pp.140-151
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• 2018

Objectives : The purpose of this study was to examine effects of adjunctive aripiprazole versus bupropion, on depressive symptoms of female depression. Methods : Sixty six female patients with major depressive disorders were enrolled from a six-week, randomized prospective open-label multi-center study. Participants were randomized to receive aripiprazole (2.5-10 mg/day) or bupropion (150-300 mg/day). Montgomery Asberg Depression Rating Scale, 17-item Hamilton Depression Rating scale (HAM-D17), Iowa Fatigue Scale, Drug-Induced Extrapyramidal Symptoms Scale, Psychotropic-Related Sexual Dysfunction Questionnaire scores, and Clinical Global Impression-Severity (CGI-S) were obtained at baseline and after one, two, four, and six weeks. Changes on individual items of HAM-D17 were assessed as well as on composite scales (anxiety, insomnia and drive), and on four core subscales that capture core depression symptoms. Results : Overall, both treatments improved depressive symptoms, without causing serious adverse events. There were significant differences in the HAM-D17 total score (p=0.046) and CGI-S (p=0.004), between aripiprazole and bupropion augmentation, favoring aripiprazole over bupropion. Aripiprazole revealed significantly greater effect size in depressed mood (p=0.006), retardation (p=0.005), anxiety psychic (p=0.032), and general somatic symptom (p=0.01). Conclusion : While both treatments were effective, results of this study suggested that aripiprazole may be preferable, in treating general and core symptoms of female depression.