• Clean Technology
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• v.26 no.3
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• pp.177-185
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• 2020

All coal ash, generated from coal-fired power plants, is entirely dumped onto a landfill site. As coal ash contains 80% fly ash, a clean floating process was developed in this study to recover useful components from coal ash and to use them as high value-added industrial materials. When the unburned carbon (UC) was recovered from the fly ash, soybean oil, an eco-friendly vegetable oil, was used as collector instead of a non-ionic kerosene collector to prevent the occurrence of odor from the kerosene. After the UC was separated by flotation, particulate ceramic microsphere (CM) was recovered, without generating acidic wastewater, through hydro-cyclone instead of sulfuric acid solution in order to separate ceramic microsphere (CM) and cleaned ash (CA) from the residue. By utilizing soybean oil as a collector, the recovery rate of UC turned high at 85.8% due to the increased adsorption of UC, the high viscosity of soybean oil, and the increase in floating properties caused by the linoleic acid contained in soybean oil. All of the combustible components contained in the recovered UC were carbon components, with the carbon content registering high when soybean oil was used. The recovered UC had many pores with a rough surface; thus, it could be easily ground and then used as an industrial material for its fine particles. The CM and CA recovered by the clean separation process using hydro-cyclone had a spherical shape, and the particles were clearly separated without clumping together. The average diameter (D₅₀) of the particles was 5 ㎛, so it was possible to realize the atomization of CM through a process change.

• Resources Recycling
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• v.12 no.2
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• pp.45-53
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• 2003

In 2001, Korea produced a total of 4.91 million metric tons of fly ash, approximately 63.3% of which was recycled. Almost all of the recycled fly ash are used in concrete mixtures and cement industry. Therefore, in order to develop a new usage to increase the utilization of the fly ash, conductive induction was used in this research rather than triboelectrostatic. By applying conductive induction, we could verify the possibility of obtaining high purity fly ash below 1%LOI and high carbon fly ash over 70%LOI from raw fly ash. In this test, the potential difference between the two electrodes was conducted by changing the range of 8 to 16 kV.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.30-30
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• 2018

해상교통사고의 가장 큰 책임은 사람에게 있기에 사람이 발생시킬 수 있는 사고의 요인을 명확하게 파악하고 선별할 수 있는 대책을 마련할 필요가 있다. 특히 사고를 발생시키는 근본적인 원인은 개인 스스로도 지각하지 못하는 적성상의 결함요인에 의해 발생할 가능성이 높다. 따라서 사고의 예방을 위해 개인의 적성에 대해 명확히 개념화 하고 측정하여 관리할 필요가 있다. 본 연구에서는 항해사의 적성검사도구 개발을 위한 기초연구로서, 항해사 개인특성에 대한 사전연구 분석, 전문가 회의 및 설문조사 결과를 종합하여 항해사의 사고경향성 평가요인을 선정하고자 하였으며, 이를 기반으로 항해사의 사고경향성을 평가할 수 있는 항해사 적성검사도구의 프로토타입을 개발하고자 하였다.

• (The) Korean Journal of Educational Psychology
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• v.31 no.2
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• pp.265-282
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• 2017

The purpose of this study was to applicate systematic RTI educational service by providing reading fluency program to identify high-risk students with dyslexia of a shadow zone based on their growth rate. Twenty-two students of 1st to 5th graders were selected as study subjects through "2016 Kyungi-Do Project of the Dyslexia Excellence Program". An individualized reading fluency program was provided through 8-10 sessions over a period of 3 months. The program was developed based on evidence-based reading strategies with the consideration of each student's educational needs. As results, three groups were identified with their learning growth rates: concerned, improving, and discrepancy groups. The study identified three students in a discrepancy group as students with dyslexia. Based on these results, implications and suggestions for further educational identification process along with effect programs were discussed.

• The Journal of the Korea Contents Association
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• v.11 no.10
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• pp.333-341
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• 2011

To compare between calcium scoring CT (CSCT) and Low-dose CT (LDCT) image finding for coronary artery calcification (CAC) in screening of lung disease by MDCT. A total of 61 subjects who retired-workers exposed to inorganic dust were performed LDCT and CSCT by using a MDCT scanner on the same day, after be approved by the institutional review board, and obtaining the written informed consent from all subjects. LDCT images were read for detecting lung diseases as well as CAC by a experienced chest radiologist, then the subjects were divided either the positive group with CAC or the negative group without it. The CSCT was used to quantify and detect the presence of calcification in the coronary artery, and score of CAC calculated by using a Rapidia software (ver 2.8). In all coronary arteries, calcium score of positive group was higher better than that in negative group, especially in the total calcium (13.7 vs. 582.9, p=0.008) and the left anterior descending artery (3.2 vs. 249.0, p=0.006). CAC findings between CSCT and LDCT image were showed excellent agreement in cut-off point 100(K-value=0.80, 95% CI=0.69-0.91) from total calcium score. CAC findings on LDCT images showed the higher relation with CSCT. Therefore, the obstructive coronary artery disease could be predicted by CAC on LDCT images for screening of lung diseases.

• Childhood Kidney Diseases
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• v.2 no.1
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• pp.1-8
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• 1998

Purpose : To evaluate the diagnostic value of dipstick urinalysis($Multistix^{(R)}$) as a screening test for urinary tract infection(UTI) in acute febrile children. Methods : We compared dipstick uinalysis (leukocyte estease(LE) and nitrite) with microscopic urinalysis (WBC and bacteria) and urine culture in 80 children with UTI and 605 children without UTI, who were admitted due to acute fever at EWHA Womans University Hospital between Oct. 1994 and Feb. 1996. Results : 1) In dipstick urinalysis, LE and nitrite were positive in 38.7%, and 13.8% of 80 children with UTI and in 2.1%. and 1.2% of 605 children without UTI. 2) In microscopic urinalysis, WBC and bacteria were positive in 31.2%, and 17.5% of 80 children with UTI and in 4.1%, and 0.6% of 605 children without UTI. 3) Positive rate of LE on dipstick urinalysis was 38.7%, which was significantly higher than 31.5% of WBC on microscopic urinalysis (P<0.05). Positive rate of nitrite was not significantly different to that of bacteria. 4) Sensitivity, specificity, positive predictive value, negative predictive value of dipstick urinalysis were 43.7%, 98.3%, 63.6%, 92.9% which were not significant different to 40.0%, 99.0%, 54.0%, 92.3% of microscopic urinalysis. The sensitivity of combined dipstick and microscopic urinalysis were still low(50%). 5) Additional positive rate of microscopic urinalysis to negative dipstick urinalysis was 6.3%(5/80) in 80 children with UTI. Conclusion : The sensitivity of dipstick urinalysis was low and additional value of microscopic urinalysis was minimal in febrile UTI. So urine culture is mandatory in acute febrile children even though dipstick and microscopic urinalysis are negative.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.15 no.1
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• pp.35-39
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• 2015

Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency is the most common mitochondrial fatty acid oxidation disorder which is inherited as an autosomal recessive pattern. MCAD deficiency is caused by mutations in the ACADM gene; medium-chain acyl-CoA dehydrogenase gene (ACADM; OMIM 607008) on chromosome 1p31 which encodes MCAD, the mitochondrial enzyme which catalyzes the first reaction in beta-oxidation of fatty acids with medium-chain length. Here, we describe one Korean pediatric case of MCAD deficiency, which was diagnosed during newborn screening by tandem mass spectrometry and confirmed by molecular analysis. The level of hexanoyl (C6), octanoyl (C8), decenoyl (C10:1) carnitine, and C8/C2 ratio was elevated. Homogenous c.1189T>A (p.Tyr397Asn) mutation of ACADM gene was identified by direct sequencing. He has been asymptomatic and has shown normal growth and development by 25 months of age without any intervention. There was no episode of metabolic acidosis during follow-up period.

• The Journal of Korean Association of Computer Education
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• v.17 no.3
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• pp.75-84
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• 2014

It is a current situation that a large number of physical and financial damages are increasing due to the growth of intellectual cyber crime and unexpected Internet incidents year by year. In the large scale security incidents, digital forensics techniques for computer crime investigations are essential to secure a place in the field. However, qualified digital forensics investigators who complete with digital security technology are practically insufficient in domestic. In this paper, as one of developing human resources plans regarding to scientific investigation of Internet security incidents, an undergraduate curriculum per stage in digital forensics was proposed. For the effective curriculum per stage, the interviews, group discussion on focused group of existing digital forensics investigators and related research were performed to select curriculum, and then the level of difficulty and practical suitability on each subject designed were analyzed through survey and interview to current investigators and security professionals. After collating the survey, the digital forensic curriculum per level was designed to highly adaptable workforce for the future for working and positive suggestions and proposals are addressed.

• Microbiology and Biotechnology Letters
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• v.14 no.4
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• pp.305-310
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• 1986

To improve the starch fermentation ability of yeast, hybrids were introduced by protoplast fusion of S. cerevisiae and S. diastaticus. The protoplasts of parental auxotrophic cells were fused in the presence of 10 mM CaCl$_2$and 30% of polyethyleneglycol (M.W 4, 000). The frequencies of fusant formation varied depending upon the strains used and were 3.51$\times$10$^{-4}$ to 5.04$\times$10$^{-4}$ for the regenerated protoplasts. The strains capable of extensive starch hydrolysis produce only 10% to total fusants. The 4 strains were finally selected by the results of starch fermentation and genetic stability test. The DNA content and cell volume of the fusants were greater than those of the parental strains.

• The Journal of the Convergence on Culture Technology
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• v.8 no.2
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• pp.59-67
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• 2022

The main purpose of this study is to quantitatively grasp the effectiveness of the gardening program by conducting a gardening program to induce active activities of the elderly and to induce healing functions and social activities, and then observing the results before and after implementation. In order to achieve the purpose of the study, as a result of conducting 30 gardening programs for 20 elderly people at two elderly care facilities, the measure of depression was found to have an improvement effect as a practice-oriented program, and it was found to revitalize the elderly. In addition, it was found that the quality of life was improved by the gardening program, and it was found to be helpful in activating the brain.