• Journal of the Korean Home Economics Association
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• v.35 no.4
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• pp.257-268
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• 1997

The effects of water-and oil-repellent finishes on the deposition and removal of oily soils from polyseter fabrics were investigated in this study. The polyester fabrics treated with three kinds of fluoropolymers(TG-410H, TG-990) were soiled with mixed oily soils and washed by using Terg-O-Tometer at various conditions. It was found that TG-410H and TG-527 treated polyester fabrics reduced significantly the deposition of oily soils than untreated and TG-990 treated polyester fabrics. The removal of oily soils from polyester fabrics was increased in porportion to increasing of surfactant concentration up to a certain point(0.2% owb) but it levelled off above the point. The removal effect was high in the order of TG-990 treated polyester fabrics > untreated polyester fabrics > TG-527 treated polyester fabrics > TBG-410H treasted polyester fabrics. Especially the removal of oily soils from polyester fabrics was more effectively removed in triton X-100 solution. In general the removal of oily soils from polyester fabrics treated with fluoropolymers was increased up to a miximum near 6$0^{\circ}C$ and than decreased above 6$0^{\circ}C$. And efficient removal could be achieved within relatively short time (30min) The removal of oily soils from polyester fabrics was increased in proportion to increasing of pH range up to a certain point(9.5 or 11.0) but it began to decrease above the point. Furthermore the removal of oily soils was increased with th increase of mechanical agitation, but it began to decrease above 160 rpm.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.2
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• pp.8-16
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• 2001

To manufacture toilet tissue with ONP (old newspaper), the effect of fractionation fiber (R150, R100, R70 mesh) and bleaching(P, PY), blending (70/30) with MOW(mixed office wastepaper) or WL(white ledger) and the addition of softener on the optical and mechanical properties were studied. Considering the pulp yield, brightness and strengths, fibers of R100 mesh fraction were proper to be produced to toilet paper from ONP. This pulp showed the pulp yield of 76.8%, brightness of 50.2% ISO and tensile index of 21.1 Nm/g. By the bleach with P and PY stages, the brightness of the pulps increased up to 60.3% ISO and 61.8% ISO, respectively. When blended with MOW (57.3% ISO) or WL (76.2% ISO), the brightness of the former increased up to 58.5% ISO, the latter up to 63.6% ISO. The strengths of pulp blended with WL were higher than those of fractionated pulp from 100% ONP, however there was no difference in strengths between fractionated pulp and blended pulp wth MOW. While the addition of softener improved the softness of paper, but it decreased strengths of pulp and extended dispersing time in water.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.10
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• pp.28-37
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• 2011

Though Korea has introduced CBP(Cost Based pool) power trading system since 2001, long-term Generation system planning has been executed by government for Cost minimization every 2 years. Until currently the model which is used for Generation system planning and best-mix only considers cost minimization and total yearly or quarterly electricity demand every year. In a view point of one day power supply operation, technical characteristics, like the ramp up/down rate of total generation system, minimum up/down time and GFRQ(Governor Free Response Quantity), are very important. this paper analyzes Optimal Fuel-Mix for 2022 Korea generation system satisfying these constraints of each fuel type and considering pump storage plants, construction cost and $CO_2$ emission charge Using MILP(Mixed Integer Linear Programming) method. Also the sensitivity analysis which follows in future power industry environmental change accomplished.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.383-386
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• 2003

In this study, the MMA-modified paste mixed waste rubber powder, which has a small elastic modulus and a large modification, was produced by using the soft unsaturated polyester resin(UP) as a binder. Then the adhesive properties according to the matrices in both underwater and air-dry conditions and the hardening shrinkage according to the contents of shrinkage reducing agent(SRA) and of MMA were surveyed. The experimental results show that, regardless of humidity of matrices the adhesive strength of polymer concrete was larger than cement concrete. the adhesive strength of MMA content of 20% was larger than MMA content of 30%. regardless of matrix materials the adhesive strength in water condition were $20{\sim}30%$ comparing with the air-dry condition. The case of MMA content of 20% showed the largest adhesive strength. In the hardening shrinkage experiment, the hardening shrinkage reduced as MMA and SRA contents increased, and the decrease of the hardening shrinkage by SRA was larger.

• Journal of Chest Surgery
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• v.24 no.1
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• pp.48-53
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• 1991

This report documents the clinical k pathologic features of 33 patients treated for thymoma for 11 years & 6 months between September 1977 and February 1989. At the Thoracic & Cardiovascular Surgery, Yonsei University, College of Medicine of the group, 31 patients treated with surgery were examined for the result of operation & prognosis. Mean age was 50 years. Thirteen were female and twenty were male. Dyspnea on exertion and chest discomfort were common in the patients without myasthenia gravis. Fourteen patients[42.6%] had myasthenia gravis and one patient had autoimmune thyroid disease. Four patients[12.1%] presented without symptoms attributable to their thymoma. Histologic review disclosed 12[36.4%] epithelial thymoma, 10[30.3%] mixed lymphoepithelial, 9[27.3%] lymphocytic, 1[3.0%] spindle cell and 1[3.0%] unknown cell thymoma. They were classified according to Masaoka`s clinical staging criteria; by these criteria, 8 patients were stage I, 5 patients were stage II, 15 patients were stage III and 3 patients were stage IV. Total excision of mass was possible in 20 patients. Partial excision of mass in 4 patients and biopsy in 7 patients were carried out during the operation. There was only one operation mortality. Follow-up was possible in 26 patients and follow-up ranged from 4 months to 10.5 years[mean 28.9 months]. One-year survival rates were 77.8% and eight patients expired during follow-up period. Eleven[78.6%] patients with myasthenia gravis were improved after the operation. This observation suggests that the most significant factor determining the survival is whether or not total surgical excision had been performed.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.3_4
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• pp.492-502
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• 2002

The purpose of this study was to investigate the advertising appeals and consumption values expressed on cosmetic advertisements in Adolescent's magazines from 1973 to 2000. The data for longitudinal content analysis were collected from Adolescent's magazine : Junior Joongang(1973.3∼1985.12), Highteen(1986.1∼1994.9), Cci(1994.l0∼2000.12). Collected data was consisted of 542 advertisements. 1. The product categories in cosmetics advertisements, the major were Base Make-up in the past but the number of Color Make-up, Functional Make-up, and Hair-related Products had increased in 1990s. Also, there were more increasing number of imported products than domestics. 2. The trend of appeals showed change according to time and society. Overall, a great many of cosmetic advertisements had emotional approach. Before the middle of the 1980's emotional approach had decreased, and mixed(rational and emotional) approach were dominated in 1990s. 3. The major consumption values in cosmetics advertisements were effective value. Especially, it had increased from 1990s. And esthetic value was dominated in the middle of the 1970s.

• Corrosion Science and Technology
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• v.21 no.6
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• pp.423-433
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• 2022

The objective of this study was to determine whether Cymbopogon citratus extract as a corrosion inhibitor from natural tropical resources could prevent corrosion of carbon steel in sulfuric acid solution. Inhibitory action of this extract was investigated using electrochemical methods such as potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Those methods revealed corrosion rate, efficiency of inhibition, and adsorptions isotherm values when the extract was added to the sulfuric acid solution at concentration up to 500 ppm with various immersion time at ambient temperature. Results revealed that higher concentration of the extract and longer immersion time decreased the corrosion rate of carbon steel whereas the inhibition efficiency of the extract was increased up to 97.25%. The value of charge transfer resistance was increased significantly by adding the extract at concentration up to 500 ppm with an immersion time of 60 minutes. The type of the extract was a mixed inhibitor. It could inhibit the corrosion process in both anodic and cathodic sides electrochemically. Results of this study suggest that the mechanism of adsorption on the surface of carbon steel is related to Langmuir adsorption isotherm.

• The Journal of Economics, Marketing and Management
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• v.12 no.2
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• pp.19-26
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• 2024

In recent years, entrepreneurship has become a significant movement in Vietnam. Vietnamese youth has paid more attention on entrepreneurship. Local brand fashion is currently booming in Vietnam. Many young Vietnamese choose to start up in local brand fashion. Vietnamese government has show strong commitment to support entrepreneurial movement among young people. Purpose: The research focused on assessing the determinants of entrepreneurial intentions in local brands fashion in Vietnam. Research design, data and methodology: The sample size consist of 293 young Vietnamese who are passionate on starting up their business in fashion. The research method employ Exploratory Factor Analysis (EFA) and SPSS software is used to analysze the collected data. Data collection involved a mixed-methods approach, combining surveys and case studies. Results: The research findings confirm the determinants of entrepreneurial intentions in local brand fashions are Attitude towards behavior, Subjective norms, Cognitive behavioral control, Entrepreneurship education, and Capital. Conclusion: The study not only delved into the influencing elements for starting a business but also examined the current landscape of the youth-oriented local fashion brand market. Managerial implications are provided to promote entrepreneurial intention among young Vietnamese in fashion industry. Limitations and further research are also discussed to provide recommended research directions for future studies.

• Physical Therapy Korea
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• v.29 no.2
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• pp.117-123
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• 2022

Background: Push-up are effective exercises for shoulder stability. Previous studies have documented the effects of support plane and hand position and width on muscle activities during a push-up. Objects: This study aimed to investigate the changes in muscle activities in the upper extremity when performing the standard and the knee-flexed push-up with different hand shapes. Methods: A total of twenty-six healthy males participated in this study. Three different hand shapes (finger abduction, finger adduction, and fists) and two types of push-up posture (standard and knee-flexed push-up) were set as the independent variables. Electrograms were used to measure the muscle activity of the upper trapezius (UT), triceps brachii (TB), pectoralis major (PM), and serratus anterior (SA). Each participant performed the randomly assigned push-up to the sound of the metronome. The mixed-effect linear regression model was used to detect the changes in muscle activities after changing the hand shape and push-up posture. Statistical significance was set at α = 0.05. Results: The UT muscle activity was statistically significantly higher when performing push-up with fists than finger abduction (p = 0.035) or finger adduction (p = 0.044). During the standard push-up, the muscle activity in all muscles was that the push-up with fists showed the highest muscle activity compared to the finger abduction (p < 0.01) and finger adduction (p < 0.01). Regardless of the shape of the hand, UT had the lowest muscle activity compared to other muscles (p < 0.001). In contrast, the SA muscle had the highest muscle activity among four muscles during the standard push-up. Conclusion: Based on the results of this study, we suggest hand shape is related to the difficulty level of push-up either in the standard or the knee-flexed push-up, especially in the push-up with fists. In addition, knee push-up can be recommended as shoulder muscle-strengthening exercises for individuals with low shoulder muscle strength.

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.17-23
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• 2003

In Korea terrestrial fluvial sequences can be used as pedological and sedimentological markers indicating a millenium-scale environmental and climatic changes imprinted in fluvial sub-environments, which in turn are represented by the cyclicity of fluvial sands, backswamp organic muds, and flooding muds intercalations of frostcracked or dessicated brown paleosols. Post LGM and Holocene fluvial and alluvial sedimentary sequences of Korea are formed in such landscapes of coastal, floodplain, backswamp and hillslope areas. Among them, the most outstanding depositional sequences are fluvial gravels, sands and organic mud deposits in coastal, fluvial, or alluvial wetlands. The aim of this study is to explain the sedimentary sequences and palynofloral zones since the last 15,000years, on the basis of organic muds layers intercalated in fluvial sand deposits. Jangheung-ri site of Nam river, Soro-ri site of Miho river, Youngsan rivermouth site in Muan, Oksan-ri site of Hampyeong and Sanggap-ri site of Gochang are illustrated to interpret their sedimentary facies, radiocarbon datings, and palynofloral zonation. Up to the Middle to Late Last Glacial(up to 30-35Ka), old river-bed, flooding, and backswamp sequences contain such arboreal pollens as Pinus, Abies, and Picea, and rich in non-arboreal pollens like Cyperaceae, Gramineae, Ranunculaceae, and Compositae. During the LGM and post-LGM periods until Younger Dryas, vegetation has changes from the sub-alpine conifer forest(up to about 17-11Ka), through the conifer and broad-leaved deciduous forest, or mixed forest (formed during 16,680-13,010yrB.P), to the deciduous and broad-leaved forest (older than 9,500yrB.P). In the Earliest Holocene flooding deposits, fragments of plant roots are abundant and subjected to intensive pedogenic processes. During Holocene, three arboreal pollen zones are identified in the ascending order of strata； Pinus-Colyus zone(mixed conifer and deciduous broad-leaved forest, about up to 10Ka), Alnus-Quercus forest (the cool temperate deciduous broad-leaved forest, about 10Ka-2Ka), and Pinus forest (the conifer forest, about after 2Ka), as examplified in Soro-ri site of Cheonwon county. The palynological zonations of Soro-ri, Oksan-ri, Sanggap-ri, Youngsan estuary, and Gimhae fluvial plain have been recognized as a provisional correlation tool, and zonations based on fluvial backswamp and flooding deposits shows a similar result with those of previous researchers.