• Journal of The Korean Society of Agricultural Engineers
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• v.64 no.6
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• pp.1-12
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• 2022

Estuary reservoirs were artificial reservoir with seawalls built at the exit points of rivers. Although many water resources can be saved, it is difficult to manage due to the large influx of pollutants. To manage this, it is necessary to analyze watersheds and reservoirs through accurate modeling. Therefore, in this study, we linked the Hydrological Simulation Program-FORTRAN (HSPF), Environmental Fluid Dynamics Code (EFDC), and Water quality Analysis Simulation Program (WASP) models to simulate the hydrology and water quality of the watershed and the water level and quality of estuary lakes. As a result of applying the linked model in stream, R² 0.7 or more was satisfied for the watershed runoff except for one point. In addition, the water quality satisfies all within 15% of PBIAS. In reservoir, R² 0.72 was satisfied for water level and the water quality was within 15% of T-N and T-P. Through the modeling system, We applied upstream pollutant management scenarios to analyze changes in water quality in estuary reservoirs. Three pollution source management were applied as scenarios, the improvement of effluent water quality from the sewage treatment plant and the livestock waste treatment plant was effective in improving the quality of the reservoir water, while the artificial wetland had little effect. Water quality improvement was confirmed as a measure against upstream pollutants, but it was insufficient to achieve agricultural water quality, so additional reservoir management is required.

• Journal of the Korean Geotechnical Society
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• v.23 no.10
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• pp.109-119
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• 2007

As the number of CFRD constructions increases, the necessity of an accurate assessment on its behavior also has been increasing. The performance of concrete faced rockfill dam (CFRD) under different water levels is a great concern of dam engineers and designers in the world. However, domestic research on CFRD design and construction has not been performed sufficiently. This study deals with three centrifuge model tests, mainly investigates quantitatively the deformation of the concrete faced slabs and settlements on the crest with different face slab stiffness. The prototype of a centrifugal model dam is half size of domestic CFRD dam. Detailed material preparation, model design, model set-up, model instrumentation and testing procedures are presented. In order to simulate the prototype concrete faced slab, three kinds of thin fiberglass plates with different thickness were adopted in three model tests. Finally, the centrifuge test results were compared with field measurements of domestic dams, which showed that the centrifuge tests were performed successfully.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.92-92
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• 2021

체외수정을 기반으로 이루어지는 성게의 수정 과정은 성게 주변에서 형성되는 복잡한 난류 흐름의 영향을 받게 된다. 성게 몸체의 하류부에 형성되는 재순환 영역 (recirculation zone) 내에는 다양한 난류 와류 흐름이 존재하며, 이들은 성게 몸체에서 방출된 정자와 난자의 충돌을 일으키고 수정 과정에 지대한 영향을 미친다. 즉, 성게의 수정 과정을 이해하기 위해서는 성게 주변의 흐름에 대한 유체역학적 관점에서의 분석이 수행되어야 한다. 본 연구의 목적은 성게 몸체에 의해 발생한 난류 흐름이 성게의 체외 수정에 미치는 영향에 대해 조사하는 것이다. 이를 위해 본 연구에서는 상용 프로그램인 오픈폼 (OpenFaom)을 활용하여 수치 모의를 수행하였다. 성게 주변의 유동장은 LES (Large Eddy Simulation)을 기반으로 모의하였고, 정자와 난자의 확산 궤적은 라그랑지안 입자 추적 (Lagrangian Particle Tracking) 알고리즘을 통해 구현하였다. 총 5개의 유속 조건 (0.025 - 0.20 m/s) 에 대해 모의를 수행하였으며 정자와 난자 사이의 거리를 바탕으로 수정률을 산정하였다. 정자와 난자의 뭉쳐있거나 퍼져있는 공간적인 분포 형태는 Standardized Morisita 지수를 통해 수치적으로 표현하였으며 이들과 수정률과의 관계를 규명하였다. 연구 결과에 따르면 성게 수정은 유속 조건이 0.1 m/s일 때 가장 빈번하게 발생하였으며, 성게 수정의 성공 여부는 크게 2가지 조건에 의해 결정되었다. 첫 번째로, Standardized Morisita 지수가 높을수록 다시 말해 생식세포들이 공간적으로 뭉쳐있어야 하며 두 번째는, 생식세포들을 충돌시킬 수 있는 원동력인 작은 와류가 존재해야 한다. 와류의 크기가 너무 크게 되면 생식세포들은 충돌하지 않고 확산만 되기 때문에 오히려 수정률이 감소하였다. 영역별로 분석한 결과에 따르면, 성게 몸체에 의해 형성된 재순환 영역이 수정과정에 있어 가장 지배적인 영역임을 확인하였다.

• Steel and Composite Structures
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• v.48 no.2
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• pp.179-190
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• 2023

Many recent attempts have sought accurate prediction of pile pullout resistance (P_ul) using classical machine learning models. This study offers an improved methodology for this objective. Adaptive neuro-fuzzy inference system (ANFIS), as a popular predictor, is trained by a capable metaheuristic strategy, namely equilibrium optimizer (EO) to predict the P_ul. The used data is collected from laboratory investigations in previous literature. First, two optimal configurations of EO-ANFIS are selected after sensitivity analysis. They are next evaluated and compared with classical ANFIS and two neural-based models using well-accepted accuracy indicators. The results of all five models were in good agreement with laboratory P_uls (all correlations > 0.99). However, it was shown that both EO-ANFISs not only outperform neural benchmarks but also enjoy a higher accuracy compared to the classical version. Therefore, utilizing the EO is recommended for optimizing this predictive tool. Furthermore, a comparison between the selected EO-ANFISs, where one employs a larger population, revealed that the model with the population size of 75 is more efficient than 300. In this relation, root mean square error and the optimization time for the EO-ANFIS (75) were 19.6272 and 1715.8 seconds, respectively, while these values were 23.4038 and 9298.7 seconds for EO-ANFIS (300).

• Journal of Microbiology and Biotechnology
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• v.33 no.9
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• pp.1228-1237
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• 2023

The CRISPR-Cas system has emerged as the most efficient genome editing technique for a wide range of cells. Delivery of the Cas9-sgRNA ribonucleoprotein complex (Cas9 RNP) has gained popularity. The objective of this study was to develop a quantitative polymerase chain reaction (qPCR)-based assay to quantify the double-strand break reaction mediated by Cas9 RNP. To accomplish this, the dextransucrase gene (dsr) from Leuconostoc citreum was selected as the target DNA. The Cas9 protein was produced using recombinant Escherichia coli BL21, and two sgRNAs were synthesized through in vitro transcription to facilitate binding with the dsr gene. Under optimized in vitro conditions, the 2.6 kb dsr DNA was specifically cleaved into 1.1 and 1.5 kb fragments by both Cas9-sgRNA365 and Cas9-sgRNA433. By monitoring changes in dsr concentration using qPCR, the endonuclease activities of the two Cas9 RNPs were measured, and their efficiencies were compared. Specifically, the specific activities of dsr365RNP and dsr433RNP were 28.74 and 34.48 (unit/㎍ RNP), respectively. The versatility of this method was also verified using different target genes, uracil phosphoribosyl transferase (upp) gene, of Bifidobacterium bifidum and specific sgRNAs. The assay method was also utilized to determine the impact of high electrical field on Cas9 RNP activity during an efficient electroporation process. Overall, the results demonstrated that the qPCR-based method is an effective tool for measuring the endonuclease activity of Cas9 RNP.

• Journal of Korean Biological Nursing Science
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• v.26 no.1
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• pp.1-15
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• 2024

Purpose: This study aimed to evaluate the effectiveness of exercise in patients with hemophilia. Methods: We carried out a systematic review and meta-analysis in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines. A literature search was conducted of published randomized controlled trials for exercise interventions from January 1, 2014 to March 15, 2023. To estimate the size of the effects of exercise, a meta-analysis was performed using the R package "meta." Results: Five databases were searched to obtain articles published in Korean or English. Of 1,150 articles reviewed, 13 were included in the systematic review and 9 in the meta-analysis. The risk of bias was assessed using RoB 2.0. The overall effect sizes of exercise interventions, calculated as the standardized mean difference, were -0.11 (95% confidence interval [CI] = -1.41 to -1.20) for pain, -2.13 (95% CI = -3.33 to -0.93) for joint health, 9.96 (95% CI = 7.51 to 12.28) for physical activity, and 0.59 (95% CI = -0.39 to -1.56) for quality of life. Conclusion: These findings suggest that exercise is useful for improving the joint health and physical activity of patients with hemophilia. Thus, it is necessary to develop and apply exercise interventions for patients with hemophilia to reduce their pain and improve their quality of life.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.9
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• pp.130-138
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• 2018

This study was a descriptive study, analyzing the clinical judgment process that occurs in a simulation of practice education for nursing students applying to LCJR. Subjects were two nursing college students in S city. Fever scenario and apnea scenario, including mock patient, were implemented. Data collection was conducted between September, 2013 and December, 2014. Data analysis was performed using descriptive statistics, paired t-test, and Pearson's correlation of PASW statistics 18.0 program. The result of this study revealed that the clinical judgment scores of nursing college students were 30.50 for males and 29.32 for females. Nursing Clinical judgment score for the apnea scenario was higher than the score for the febrile scenario, and nursing students' self-evaluation and professors' evaluation showed a significant correlation with respect to the responding domain. In comparison the student and faculty ratings, domain of interpreting and domain of reflecting were significant This study will provide educators with foundational knowledge of program development to enhance nursing students' clinical judgment abilities. We suggest more discussion on their nursing practice and judgment during debriefing session may be beneficial for students.

• Journal of the Korean association of regional geographers
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• v.20 no.3
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• pp.344-355
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• 2014

This study examines American geography educators' familiarity and knowledge of Korea, their perception on sovereignty education, and their knowledge on Korea's sovereignty issues using the survey conducted at the annual conference of the National Council for Geographic Education (NCGE) in the United States in 2010 and 2012. This study also analyzes how much these knowledge and perception influence on values of sovereignty education and Korea's sovereignty issues and further investigates proper educational approaches on territorial issues in Northeast Asia. Knowledge on the geography of Korea of American geography educators is higher than their knowledge on Korean culture. Both experiences attending educational programs about Korea and visiting Korea further enhance their knowledge on the geography of Korea and Korean culture. They agree the importance of sovereignty education in geography education and believe that sovereignty education should promote students' sense of patriotism and encourage students to be global citizens who promote public interests. However, they value less on teaching on the economic value of their own country's territory and students' ability to understand territorial conflicts with other countries. American geography educators' perception on sovereignty education improves their familiarity with and knowledge of Korean territorial issues. This study identifies that providing opportunities to learn about Korea and Korean territorial issues can maximize geography educators' accessibility to Korean territorial issues, regardless of their interest in territorial issues. These findings help Korean government develops better strategies for formulating and implementing future international public relations practices for Korean territorial issues.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.6
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• pp.15-29
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• 2022

The Byungsan Neo-Confucian Academy, a 17th-century World Heritage Site in Korea, is being praised as a manifestation of naturalness or non-artificiality of the traditional Korean borrowed scenery technique (借景, chagyeong). This study, however, aims to reinterpret the chagyeong of the Byungsan Academy (hereafter the Academy) as a device of illusion evoking an idealized vision of nature. In the process of interpretation, 'picture and frame'-a widely accepted expression that represents the chagyeong of the Academy-will be foregrounded as the pivotal concept mediating the change of perspectives from naturalistic to ideological. This study consists of the following three parts. First, it shows that 'picture and frame' represent a modern way of seeing the Academy as an architectural heritage in harmony with nature; it denotes pristine nature and the empty architectural frame that safely circumscribes the innate beauty of the natural landscape. Second, departing from the naturalistic perspective, this study argues that the architectural framework of the Academy composes scenography enticing the viewer to imagine the idealized, Confucian image of nature that compares to the landscape imagery found in the landscape poetry and paintings that were produced and appreciated by the 17th-century Confucian literati. Lastly, based on the above interpretation, this study stresses that the 'picture' one encountered at the Academy in the 17th century was not the framed scene of a natural landscape but the illusion it caused; the architectural 'frame' worked not as a symbol of naturalness but as an institutional apparatus of vision manipulating the way one sees-and therefore imagines-the landscape.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.1
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• pp.1-8
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• 2015

Wind power systems have gained much attention due to the relatively high reliability, good infrastructures and cost competitiveness to the fossil fuels. Advances have been made to increase the power efficiency of wind turbines while less attention has been focused on structural integrity assessment of structural sub-systems such as towers and foundations. Among many parameters for integrity assessment, the most perceptive parameter may be the induced horizontal displacement at the hub height although it is very difficult to measure particularly in large-scale and high-rise wind turbine structures. This study proposes an indirect displacement estimation scheme based on the combined use of inclinometers and accelerometers for more convenient and cost-effective measurements. To this end, (1) the formulation for data fusion of inclination and acceleration responses was presented and (2) the proposed method was numerically validated on an NREL 5 MW wind turbine model. The numerical analysis was carried out to investigate the performance of the propose method according to the number of sensors, the resolution and the available sampling rate of the inclinometers to be used.