• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.11a
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• pp.263-268
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• 1999

Langasite, a new piezoelectric material was polished by CMP(chemical mechanical polishing). To enhance the polishing rate, alumina abrasives were added to commercial ILD1300 slurry which contains silica abrasive. The effect of added alumina 0 the silica slurry on the polishing rate and damage of langasite was investigated, Experimental results show that the polishing rate and roughness increases with increasing added alumina particle size, Crystallinity of the langasite is also lowered by alumina addition.

• KDI Journal of Economic Policy
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• v.42 no.1
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• pp.1-30
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• 2020

On average, small business support projects appear to improve beneficiary sales, and the growth effect is obvious when supporting young or growing firms. However, the effect is largely offset by sales reductions due to overcrowding. Small business support projects must be operated in two ways to alleviate the overcrowding of businesses in a few industries and to enhance the overall effectiveness of the support programs.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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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.

• Proceedings of the PSK Conference
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• 2003.10a
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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)

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2016.05a
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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.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.6
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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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• v.11 no.2
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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.

• Korean Journal of Exercise Nutrition
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• v.13 no.1
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• pp.15-21
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• 2009

Ergogenic aids are substances, devices, and practices that enhance an individual's energy use and production, and recovery from fatigue. L-carnitine increases enhance performance and aerobic capacity by stimulating lipid oxidation in muscle cells during long term exercise. L-carnitine is a well known and widely used ergogenic aid. In the present study, the effect of L-carnitine at concentrations of 100 nM, 1 μM, 10 μM, and 100 μM on the amplitude of field potential in rat cardiac muscle slices was measured using multi-channel extracellular recording (MED 64) system. In the present result, L-carnitine was shown to enhance field potential as a does-dependent manner. The increasing effect of the L-carnitine on field potential was not affected by application of the glibenclamide, an ATP-dependant K⁺ channel antagonist. The increasing effect of L-carnitine on field potential was suppressed by application of the diazoxide, an ATP-dependent K⁺ channel agonist. Present data show that L-carnitine potentiates field potentials by inhibition on ATP-dependant K⁺ channel in cardiac muscles. The enhancing effect of the L-carnitine on the field potential in cardiac muscles can be suggested as one of the underlying mechanism of ergogenic aid of the L-carnitine.

• Journal of Fisheries and Marine Sciences Education
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• v.21 no.1
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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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• v.55 no.1
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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.