• Membrane and Water Treatment
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• v.14 no.2
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• pp.85-93
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• 2023

Membrane separation is widely used for several applications such as water treatment, membrane reactors and climate change. Cross-linked organic-inorganic hybrid polyvinylidene fluoride (PVDF) / Tetraethyl orthosilicate (TEOS) was adopted for the preparation of optimized hollow membrane (HFM) for membrane distillation or other low pressure separators for mechanical properties and permeability under varying pretreatment schemes. HFMs were prepared on semi-pilot membrane fabrication system. Novel adopted post-treatment schemes involved soaking in glycerol, magnesium sulphate (MgSO₄), sodium hypochlorite (NaOCl), and isopropanol for different durations. All fibers were characterized for morphology using a scanning electron microscope (SEM), surface roughness using atomic force microscope (AFM), elemental composition by examining Energy Dispersive Spectroscopy (EDS), water contact angle (CA°) and porosity. The performance of the fibers was evaluated for pure water permeation flux (PWF). Post-treatment with MgSO₄ gave the highest both tensile modulus and flux. Assessment of properties and performance revealed comparable results with other organic-inorganic separators, HF or flat. In spite of few reported data on post treatment using MgSO₄ in presence of TEOS, this proves the potential of low cost treatment without negative impact on other membrane properties. The flux is also comparable with hypochlorite which manifests substantial precaution requirements in actual industrial use.The relatively high values of flux/bar for sample treated with TEOS, post treated with MgSO₄ and hypochlorite are 88 and 82 LMH/bar respectively.

• Journal of Periodontal and Implant Science
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• v.54 no.4
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• pp.265-279
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• 2024

Purpose: The aim of current study was to evaluate percentage root coverage (RC%) in isolated Miller class III/RT2 labial gingival recession (GR) associated with malaligned mandibular anteriors, using interdisciplinary periodontal-orthodontic treatment as compared to mucogingival surgery alone. Methods: Thirty-six systemically healthy patients having isolated Miller class III/RT2 GR with respect to malaligned mandibular anteriors, were randomly divided into test group: mucogingival surgery using subepithelial connective tissue graft followed by orthodontic treatment and control group: mucogingival surgery alone. Primary clinical parameters included (RC%), recession depth, keratinized tissue width, mid-labial clinical attachment level, interdental clinical attachment level (iCAL), periodontal phenotype (PP), gingival thickness (GT), root coverage esthetics score (RES) and hypersensitivity. Total duration of follow up was 12 months. Results: Mean RC% was significantly more achieved in test group (66.67%±40.82%) in comparison to control group (39.93%±31.41%) at the end of study (P=0.049). Further, complete root coverage was attained in 5/8 cases of test group versus 1/2 cases of control group after 3/12 months respectively. RES and hypersensitivity, showed statistically significant improvement after complete follow up period in both the groups. An ideal RES score of 10 was achieved in 4/7 cases of test group while in 1/2 cases of control group after 3/12 months respectively. Correlation analysis revealed significant negative correlation between RC% and iCAL. Correlation of RC% with GT and PP was non-significant. Conclusions: Interdisciplinary periodontal-orthodontic approach may be more beneficial in terms of achieving improved RC%, esthetic and resolution of hypersensitivity in the management of Miller class III/RT2 GR in malaligned mandibular anteriors.

• Journal of the Earthquake Engineering Society of Korea
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• v.13 no.5
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• pp.41-50
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• 2009

Following an earthquake, the major concerns for damaged buildings are their safety/risk in the event of aftershocks, and thus a quantitative damage assessment must be performed in order to evaluate their residual seismic capacity and to identify necessary actions for the damaged buildings. Post-event damage evaluation is therefore as essential for the quick recovery of a damaged community as pre-event seismic evaluation and strengthening of vulnerable buildings. The objective of this study is to develop a post-earthquake seismic evaluation method for RC frames with URM infill wall for typical school buildings. For this purpose, full-scale, one-bay, single-story specimens having different axial loads in columns are tested under cyclic loadings. During the tests, residual crack widths, which can also be found in damaged buildings, are measured in order to estimate the residual seismic capacity from the observed damage. In this paper, the relationship between the measured residual crack width and the residual seismic capacity is discussed analytically and experimentally, and reduction factors are proposed to estimate the residual seismic capacity based on the observed damage level.

• KEPCO Journal on Electric Power and Energy
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• v.4 no.1
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• pp.33-38
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• 2018

This study applied upgrades to the processes of a 10 MW wet amine $CO_2$ capture pilot plant and conducted performance evaluation. The 10 MW $CO_2$ Capture Pilot Plant is a facility that applies 1/50 of the combustion flue gas produced from a 500 MW coal-fired power plant, and is capable of capturing up to 200 tons of $CO_2$. This study aimed to quantitatively measure efficiency improvements of post-combustion $CO_2$ capture facilities resulting from process upgrades to propose reliable data for the first time in Korea. The key components of the process upgrades involve absorber intercooling, lean/rich amine exchanger efficiency improvements, reboiler steam TVR (Thermal Vapor Recompression), and lean amine MVR (Mechanical Vapor Recompression). The components were sequentially applied to test the energy reduction effect of each component. In addition, the performance evaluation was conducted with the absorber $CO_2$ removal efficiency maintained at the performance evaluation standard value proposed by the IEA-GHG ($CO_2$ removal rate: 90%). The absorbent used in the study was the highly efficient KoSol-5 that was developed by KEPCO (Korea Electric Power Corporation). From the performance evaluation results, it was found that the steam consumption (regeneration energy) for the regeneration of the absorbent decreased by $0.38GJ/tonCO_2$ after applying the process upgrades: from $2.93GJ/ton\;CO_2$ to $2.55GJ/tonCO_2$. This study confirmed the excellent performance of the post-combustion wet $CO_2$ capture process developed by KEPCO Research Institute (KEPRI) within KEPCO, and the process upgrades validated in this study are expected to substantially reduce $CO_2$ capture costs when applied in demonstration $CO_2$ capture plants.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.22 no.4
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• pp.416-423
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• 2015

Purpose: The purpose of this study was to evaluate the effect of a self-evaluation method using video recording on competency in nursing skills, self-directed learning ability, and academic self-efficacy in nursing students. Methods: The study design was a non-equivalent pre-post quasi-experimental design. The experimental and control groups were randomly assigned with 35 participants in each group. Interventions for the experimental group were video recording and students' self-evaluation of what they did. Nursing skills included in the study were tube feeding, intradermal injection, subcutaneous injection, and intramuscular injection. Competency in nursing skills was measured one time at the end of the study using a checklist. Self-directed learning ability and academic self-efficacy were measured 3 times (pre-, mid-, and post-intervention) over the 8 weeks. Independent t-test, chi-square test, and repeated measures ANOVA were used for data analyses. Results: There was no statistically significant difference for competency in nursing skills and self-directed learning ability over the 8 weeks of the practice session. There was a significant difference in academic self-efficacy by groups over time. Conclusion: Results indicate that self-evaluation method using video recording is an effective learning way to improve academic achievement in nursing students.

• Archives of Plastic Surgery
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• v.37 no.2
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• pp.195-198
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• 2010

Purpose: The zygoma is a key element which composes the facial contour. Zygomatic fracture induces facial asymmetry. We use radiologic evaluation or inspections mainly for identification of symmetry after reduction depressed zygomatic fracture. But the disadvantages of such methods are time-consuming and complicated process. So we tried to develop a new testing method with a ruler and a level. Methods: In unilateral depressed zygomatic fracture patient, parallel to the patient's head to make sure lay horizontaly. Put the leg of a ruler on the malar eminence so that it is at the same distance from the facial midline. Then take the level of malar eminence as put the level above the ruler. This process was performed before and after the reduction. Results: We were able to fix with plate and screw after checking the results of reduction fast and easily. Good results were obtained at post-operative radiologic evaluation. Conclusion: We can easily get the ruler and level around life. This method is not only simple but also shorttime process compared with other method-radiologic evaluation or inspection. And the operator can explain the results to the patients easily and objectively. Authors obtained the good results with this new method, and would introduce it for another method of identifying the result of reduction in depressed zygomatic fractures.

• Human Ecology Research
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• v.56 no.6
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• pp.555-571
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• 2018

This study identified the characteristics of fashion rental service users as well as analyzed their purchase decision-making processes. A qualitative investigation was conducted through in-depth interviews with 13 women in their 20s-30s who have experienced renting fashion items due to a high interest in fashion. The results of the study are summarized as follows. The need recognition stage analyzed ventilation by mass media, SNS impact, curiosity, saving shopping time and money, awareness of situational necessity, and creation of various styles. The information search stage analyzed how users obtained information from 2 different sources of nonmarketer-dominated sources and marketer-dominated sources. The pre-purchase stage analyzed the evaluation of alternatives in which study participants used 2 evaluation criteria for fashion rental services and fashion rental items. The purchase stage analyzed how participants wait and select desired items (when receiving the notification of rentable items) or select alternative products. The consumption stage examined the usage frequency and usage method. The study divided the post-consumption evaluation stage into 2 categories for evaluation: personal feelings and service. The post-consumption behavior stage analyzed how participants displayed WOM, eWOM and purchase rental product behavior. Clothing shopping orientation of study participants is displayed in 5 dimensions of brand-seeking propensity, individuality-seeking propensity, economic efficiency-seeking propensity, rationality-seeking propensity, and pleasure-seeking propensity. This study identified three main characteristics in the study participants: interest in the fashion, favorable attitude toward used fashion items, consciousness of others.

• The Journal of the Convergence on Culture Technology
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• v.9 no.1
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• pp.299-311
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• 2023

This study is to verify the development process and effectiveness of a learning strategy program for junior college students. The necessity and feasibility of learning strategy programs for junior college students were confirmed and reviewed through prior studies, and the program development process was divided into four stages: program planning, program development, program execution, and program evaluation, and integrated into program development management. In the first stage of program planning, the development direction, goals and objectives were set. In the second stage of program development, prior research analysis, content selection, program organization, and evaluation plan were conducted. In the third stage of execution, the program was executed, and in the fourth stage of evaluation, program evaluation was conducted to develop the program. In order to verify the effectiveness of the program, the test was conducted using the learning strategy diagnostic scale for junior college students to collect data, and the effectiveness was verified for the pre-, post-, and post-test scores.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.1
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• pp.83-94
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• 2002

This study was intended to identify fabric impact on decision-making process for clothing purchase, to determine evaluation factors of clothing, and to analyze consumer's preference for fabric on clothing purchase. 396 questionnaires distributed to college students were analyzed by descriptive statistics, oneway ANOVA, correlation, factor analysis and multidimensional scaling. The results are as follows; (1) Fabric impacted on the pre-purchase evaluation and the post-purchase process. (2) 4 factors - physical properties, outer-consciousness, self-satisfaction, and appropriateness- were determined as evaluation factors. Though fabric was included in the physical properties, fabric presented high correlations with other evaluative elements. (3) The most preferred fabric was being composed of natural fiber in fiber contents and having softness in sensation. As a result of multidimensional scaling, 2 dimensions of fabric sensation were developed as 'soft-hard'and 'thin-thick'.

• Journal of the Korean housing association
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• v.18 no.5
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• pp.143-150
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• 2007

The purpose of this research is to example the general trend of the service environment evaluation of the silver town and classify based on the service environment evaluation to suggest a effective method and alternatives fur development companies. The survey population of this study focused on 40s and 50s' middle aged both genders living in the Seoul and national capital region, we used random sampling method. The analytical methods used in this study were frequency, mean, standard deviation, factor analysis, Chi-Squae analysis, ANOVA, cluster Analysis, post-hoc estimation (Duncan test), To verify the reliability of each measure, Cronbach's alpha coefficient was used. As a result of classifying the environment evaluation elements, it was classified into 5 groups for the differentiating strategy on each group. The groups are: life support service type, medical and health support service type, cultural support service type, indifference type, and food support service type.