• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 II
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• pp.882-887
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• 2001

This paper deals with the effect of mass-spring-mass resonance that is a characteristics of the multi-layered panels in order to enhance sound insulation performance. From theoretical and experimental investigation, it is evident that tuning mass-spring-mass resonance by controlling elastic modulus of the core materials is very important to improve the STC value without increasing the weight of panels, resulting in enhancing STC value more than 10 dB.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-1
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• pp.44-46
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• 2003

Although Cyclosporin A (CsA) is a powerful immunosuppresant with little adverse effect on the bone marrow, CsA administered orally in the general formulation cannot obtain high bioavailability due to its poor aqueous solubility. To improve the solubility and enhance the bioavailability of poorly water-soluble CsA, many different approaches have been made in our laboratory. (omitted)

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2016년도 춘계학술대회
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• pp.130-131
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• 2016

Although many metals contaminated sediment from coastal area contain both anionic and cationic heavy metals, the current remediation technologies are not effective for stabilize heavy metals of both anionic and cationic elements from contaminated coastal region. the present work investigated the efficiency and mechanism of immobilization of Fe, Zn, Cr, Cu, Pb and Cd metal solutions in modified zeolite based biostimulant ball. Biostimulant ball containing acetate, nitrate and sulphate which are enhance the activity of marine microorganisms and it can act as electron donors and electron acceptors. Modified zeolite and chelating agent is greatly enhance the metal stabilization due to increased immobility of the analysed metals. The XRD, FT-IR and SEM of modified zeolite which cheating agents containing heavy metals were investigated. The results indicated that heavy metals could be effectively immobilized in modified zeolite and chelating agents in BSB added sediment. The immobilization of heavy metals in modified zeolite and chelating agents along with BSB could be due to stabilize of heavy metal cations. Immobilization of heavy metals using BSB with modified zeolite and chelating agent has lower cost effect and enhance the sediment quality.

• 한국토양비료학회지
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• 제49권6호
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• pp.776-782
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• 2016

Salinity has been a threat to agriculture in some parts of the world; and recently, the threat has grown. Plant growth-promoting rhizobacteria (PGPR) may benefit plant growth, either by improving plant nutrition or producing plant growth hormones. The effects of rhizobacterial strains to attenuate the salinity stress on the germination of Chinese cabbage seeds were tested using four different concentrations of NaCl (50, 100, 150, and 200 mM). Also, PGPR strains were tested to enhance the early germination of Chinese cabbage seeds under normal conditions. Azotobacter chroococcum performed best with enhancing the radicle length of 4.0, 1.2, and 1.0 times at treatments of 50, 100, and 150 mM of NaCl, respectively. Additionally, significant differences were found in plumule length, A. chroococcum and Lactobacillus sp. showed remarkable activation either in normal or under stress conditions. Co-inoculation by three rhizobacterial strains (LAPmix) indicated synergistic effect to enhance the early germination of the seeds. The results of this study are promising for application of rhizobacterial strains that possess plant growth promoting traits to enhance the plant tolerance against salinity.

• Advances in concrete construction
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• 제11권2호
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• pp.163-171
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• 2021

This paper studies the effect of using multi-scale reinforcement additives on mechanical strengths, damage performance, microstructure, and water absorption of cementitious composites. Small dosages of carbon nanotubes (CNTs) or polypropylene (PP) microfibers; 0.05%, 0.1%, and 0.2% by weight of cement; were added either separately or simultaneously into cement mortar. The experimental results show the ability of these additives to enhance the mechanical behavior of the mortar. The best improvement in compressive and flexural strengths of cement mortar reaches 28% in the case of adding a combination of 0.1% CNTs and 0.2% PP fibers for compression, and a combination of 0.2% CNTs and 0.2% PP fibers for flexure. Adding CNTs does not change the brittle mode of failure of plain mortar whereas the presence of PP fibers changes it into ductile failure and clearly enhances the fracture energy of the specimens. Scanning electron microscopic (SEM) images of the fracture surfaces highlights the role of CNTs in improving the adhesion between the PP fibers and the hydration products and thus enhance the ability of the fibers to mitigate cracks propagation and to enhance the mechanical performance of the mortar.

• 운동영양학회지
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• 제13권1호
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• pp.15-21
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• 2009

Ergogenic aids는 에너지를 많이 소비하는 운동선수들이나 혹은 일반 사람들일지라도 기대 수준 이상으로 운동수행능력을 개선시키거나 향상시키기 위하여 흔히 사용하는 여러 가지 물질이나 처치들을 말한다. L-carnitine은 장시간 운동을 하는 동안 근육세포의 지질산화 자극에 의해 운동수행능력 증진과 유산소능력을 증진시키며 운동 수행력 증진제로 잘 알려져 있다. 본 연구에서는, 흰쥐 심근에서 유발된 field potential에 대한 L-carnitine의 작용을 통해, 심장 세포들 사이의 네트워킹으로 유도되는 세포활성 작용 기전에 미치는 영향을 확인하였다. Field potential은 multi-channel extracellular recording system(MED64 system)으로 측정하였고, L-carnitine을 100 nM, 1 μM, 10 μM, 그리고 100 μM의 농도로 처리하여 대조군에서 측정된 전류의 크기와 비교하여 결과를 분석하였다. 본 실험의 결과 심근세포에 L-carnitine을 투여 시 field potential이 증가하였다. L-carnitine과 ATP-dependant K⁺ channel 길항제인 glibenclamide을 투여 시에는 field potential의 증가가 유지된 반면, L-carnitine과 ATP-dependent K⁺ channel 효현제인 diazoxide을 투여 시에는 증가된 field potential이 다시 감소되었다. 본 연구에서는 L-carnitine이 ATP-dependant K⁺ channel을 억제하여 field potential을 증가시키는 작용이 L-carnitine의 ergogenic aids로서의 새로운 기전으로 제시될 수 있다.

• 수산해양교육연구
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• 제21권1호
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• pp.1-15
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• 2009

The purpose of this study was to examine the effect of a career exploration program using career portfolio for vocational high school students and suggest ideas for making a decision their career and occupation. The number of subjects in this study were 50 high school students in Busan metropolitan city among which 25 were assigned for the experimental group and 25 in the control group. The career exploration program utilizing career portfolio in this study was composed of 12 sessions utilizing the career portfolio. This program was based on Jeong et al.'s career development program(2005) for high school students and Choi's career exploration program using internet(2005). The instruments of this study were self-efficacy scale and career identity scale. The average, standard deviation and the differences between the pre and post-test were calculated and processed by SPSS WIN 14.0. The major findings of this study can be summarized as follows: First, the career exploration program using career portfolio was effective to enhance significantly the level of the self-efficacy of vocational high school students. Second, the career exploration program using career portfolio was also effective to enhance career identity.

• Human Ecology Research
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• 제55권1호
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• pp.57-66
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• 2017

This study investigates the effect of a leadership program to enhance leadership skills in children from low-income families. A total of 45 elementary school students participated in the 52-week leadership program. Five leadership scales, such as goal attainment, paradigm shifting skills, skills to lead others, human relationship skills, and sense of purpose, were measured through survey questionnaires before and after implementing the program. In addition, individual teacher interviews examined the influence of the program on students' leadership skills. This study found that participants showed significant improvement after implementing the program in the three domains of the leadership skills (goal attainment, paradigm shifting skills, and human relationship skills); however, the skills to lead others and sense of purpose did not significantly change. The leadership teachers also stated that the program influenced positively on students' leadership skills; in addition, students' behavioral changes were found by developing relationships with other children as well as contemplating and attempting to find a future dream and vision. The leadership program was effective to enhance leadership skills in children from low-income families. This study can provide the theoretical and practical foundations for the development and implementation of effective leadership programs that meet the needs of children from low-income families.

• BMB Reports
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• 제30권5호
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• pp.308-314
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• 1997

We investigated biotinylation of nitrocellulose membrane for immuno-filtration capture assay. In order to enhance the efficiency of biotinylation, nitrocellulose membranes were pretreated with several chemicals for the purpose of suitable protein absorption through surface modification. As a signal generating enzyme, urease was used and the concentration of avidin was optimized for the efficient binding kinetics between urease-biotin in liquid phase and biotinylated membrane in solid phase. For effective biotinylation, bovine serum albumin-biotin complexes could be immobilized at a concentration of $370\;{\mu}g$/stick ($4.4\;cm^2$). Among tested chemicals, polylysine (0.25%) showed a significant effect in biotinylation. Polylysine is thought to enhance surface area by extending unbound residues into solution. Time of treatment over 30 min and higher molecular weight of polylysines (58,100 dalton) showed positive effect on the enhancement of biotinylation. The result from this study may be useful for developing a new biosensor and other biofunctional membranes for examining molecular recognition.

• 무역상무연구
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• 제69권
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• pp.655-672
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• 2016

The main objective of this study is to examine the mediating effect of 'e-trust' on the relationship between the antecedents related to e-marketplace and the intention of using e-marketplace. Data was collected from a survey of 169 exporting firms in Gwangju, Korea. The results of the study are as follows ; First, 'e-trust' is produced a mediating effect when technology and government factors affect the intention of using e-marketplace. However, "e-trust" does not play a mediating role in the relationship between company factor and the intention of using e-marketplace. Second, technology factor, government factor and company factor have a positive impacts on the intention of using e-marketplace. Accordingly, in order to enhance the intention of using e-marketplace, small & medium exporting firms in Korea should try more to prepare for factors related to technology and company. In addition to these, government should give full support to be prepared for regulations and systems related to e-marketplace. If e-trust were properly built, the enhancement of using e-marketplace would be taken place more smoothly. So most of exporting firms can participate in e-marketplace more actively.