• Journal of the Korean Ceramic Society
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• v.37 no.10
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• pp.987-993
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• 2000

Bayer 공정은 보오크사이트로부터 수산화알루미늄을 추출시키는 가장 일반적인 방법으로서 공정 조건에 따라 수산화알루미늄의 1차입자경, 입도분포도 및 생산효율 등이 달라지게 된다. 이러한 수산화알루미늄의 특성에 영향을 미치는 석출인자로는 가성소다 농도, 석출온도, 종자투입량 및 알루미나와 가성소다 농도비 등이 있다. 본 실험에서는 이러한 각각의 인자들이 수산화알루미늄 석출시 입자성장에 미치는 영향을 연구하였다. 그 결과 입자성장에 가장 큰 영향력을 미치는 인자는 석출온도와 종자 투입량이며 A/C비 및 가성소다 농도는 큰 영향을 주지 않음을 알 수 있었다.

• Vending industry
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• v.1 no.4 s.4
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• pp.40-53
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• 2002

지난 97년도를 기억하는 가. 그해 연말은 사상 초유의 IMF 부채국으로의 전락이라는 오욕과 뼈를 깎는 불황의 전주곡을 울렸던 해였기는 했지만, 아이러니컬하게도 자판기 산업은 사장 최대의 실적을 기록한 해다. 그러나 다음해인 98년부터 2000년까지는 시장성은 급락 직하하는 마이너스 성장기를 맞는다. 고도성장을 해 나가야 할 자판기 산업에 오히려 브레이크가 걸렸고, 지난 3년간의 통계조사 속에는 그러한 산업의 좌절과 아픔이 깊게 베어 있다. 하지만 산업계는 금번 2001년도 통계조사 분석 결과를 반갑게 받아들일 수 있게 됐다. 산업계는 온갖 어려움을 극복하고 마침내 산업 성장을 견인해 낸 것. 금호 기획특집에서는 성장세를 견인한 2001년 자판기 산업의 모든 것을 통계분석을 통해 대해부하는 시간을 마련했다

• Digital Contents
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• no.10 s.77
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• pp.49-51
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• 1999

2.4분기에는 개인 컴퓨터를 비롯해 PC통신, 인터넷, 휴대폰 동의 급격한 보급 증가와 더불어 정보서비스 이용량이 급격하게 늘고 있는 것으로 나타났다. 최근 정보통신부의 조사에 따르면 보급수준(이용자수)과 이용수준(매출액)을 종합한 정보이용 동향을 분석한 결과 1999년 2/4분기 정보 이용지수 성장률은 1/4분기 15.19% 의 성장률에 비해 1.19% 증가한 16.38%로 높은 성장률을 지속한 것으로 나타났다.

• Proceedings of the Korean Reliability Society Conference
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• 2005.06a
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• pp.157-163
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• 2005

신뢰성성장시험관리는 제품개발프로그램의 초기단계에서 고장모드를 확인하고, 이를 개선 또는 제거하기 위해 설계를 변경하고, 그 결과 진행되는 신뢰성이 향상되는 변화를 추적할 수 있는 실용적인 방법이다. 본 연구의 목적은 AMSAA(Army Materiel Systems Analysis Activity)모델을 이용하여 신뢰성 성장을 계획하고 평가할 수 있는 실용적인 방법을 제시하는데 있다. 시험-개선 과정을 통하여 성장하는 신뢰성 수준의 변화에 대한 추적과 예측 가이드라인을 제시함으로써 현장에서 활용할 수 있는 방법을 보여준다.

• The Korean Journal of Malacology
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• v.16 no.1_2
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• pp.25-29
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• 2000

In order to investigate the optimal environment factor for growth of the cockle shell, Anadara granosa bisenensis, tolerance experiment to the water temperature and salinity have been conducted. In the tolerance experiment to the temperature A. granosa bisenensis survived a very wide range from 3$^{\circ}C$ to 33$^{\circ}C$, but their survival rate was lower at higher water temperature up to 35$^{\circ}C$. In the case of salinity their tolerance range was from 0$\textperthousand$ to 100$\textperthousand$ and showed higher survival rate at lower salinity. Growth in shell length and total weight of the spat at the end of the rearing experiment was 13.17${\pm}$0.98 mm and 0.69${\pm}$011 g.

• Korean Journal of Crystallography
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• v.3 no.2
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• pp.98-110
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• 1992

B-SiC thin films were fabricated on Si(100) substrate under 1 atom by fVD. The effects of deposition conditions on the growth and the properties especially crystallinity and prefer ential alignment of these thin films were investigated. SiH4 and CH4 were used as source gases and H2 as Carrier gas. Th9 growth Of B-SiC thin films with changing parameters such as the growth temperature, the ratio of source gases (SiH4/CH4 ) and the total amount of source gases. The grown thin films were characterized by using SEM, a -step, XRD, Raman Spectro- scopy and TEM. Chemical conversion process improved the quality of thin films due to the formation of SiC buffer layer. The crystallinity of SiC thin films was improved when the growth temperature was higher than l150t and the amount of CH4 exceeded that of SiH4. The better crystallinity, the better alignment to the crystalline direction of substates. TEM analyses of the good quality thin films showed that the grain size was bigger at the surface than at the interface and the defect density is not depend on the ratio of the source gases.

• Journal of Aquaculture
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• v.13 no.3
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• pp.231-238
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• 2000

Growth, feed efficiency and condition factor of the olive flounder fed supplemented diets containing different levels of Obosan were significantly (P<0.05), especialluy at the optimum level of 0.6% Obosan. The hematological values (RBC count, hemoglobin, hematocrit, MCHC, MCV and MCH) were not significantly different among the flounder fed diets containing different levels of Obosan (P> 0.05). However, serum concentrations of total protein and glucose in the flounder, feds Obosan supplemented diets, were significantly higher, while the levels of total cholesterol, COT and GPT were lower than those of control fish (P<0.05)i the values for COT and GPT were only about half that of the control (P<0.05).

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.2
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• pp.63-68
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• 2021

This study was focused to investigate the effect of NbC-coated crucible on the quality of the SiC crystals. Then, the different properties between SiC crystals grown in a conventional graphite crucible and NbC-coated crucible were systematically compared. SiC crystals were grown using the Physical Vapor Transport (PVT) method at a temperature of 2300℃ and a pressure of 5 Torr in Ar atmosphere. After grinding and polishing, the polytype of the grown SiC crystal was analyzed using Raman spectroscopy, and crystallinity was confirmed by HR-XRD. Furthermore, the defect density and the concentration of impurities were analyzed by an optical microscope and a SIMS, respectively.

• Journal of The Korean Association For Science Education
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• v.43 no.1
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• pp.29-36
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• 2023

This study investigates the effects of the operation of science activity program on scientific literacy focusing on science cultural literacy and core competencies for pre-service teachers. 255 pre-service teachers of K University participated, and the effects of the program were examined through a paired-sample t-test with one group pretest-posttest design for science cultural literacy. Only the post-test was conducted on core competency growth perception, and differences in growth perceptions by competency were compared using ANOVA. As a result of the study, the average of pre-service teachers was higher than the pre-test for science culture literacy, and this difference was statistically significant (p<.05). In the core competency growth perception, 70.6% of pre-service teachers reported growth in scientific communication ability, and as a result of the post-hoc test using LSD, it shows statistically significant growth compared to other competencies (p<.05). Through this, it was possible to confirm the educational value of the science activity program as a way to develop pre-service teachers' scientific literacy.

• Journal of Life Science
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• v.29 no.5
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• pp.614-620
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• 2019

The purpose of this study was to examine the growth plate, femoral bone length, bone mineral density, and blood composition in various experimental animals fed with oriental medicinal herbs containing growth factors. First, the lengths of the bone growth plates of the positive control (PC) group (fed with Astragalus membranaceus) and the Gh-199 and Sh-188 groups were increased when compared to group N. The Gh-199 group showed a greater increase in bone growth when compared with the PC group. In terms of the femoral bone length and bone mineral density, the effect of both Gh-199 and Sh-188 powders were as good as those of the PC group, and the Gh-199 powder showed a positive effect. Conversely, in the PC group, unlike the Gh-199 and Sh-188 groups, the aspartate aminotransferase(AST) and alanine aminotransferase(ALT) activities in the blood were increased, indicating that A. membranaceus is toxic to the body. Both the PC and Sh-188 groups also showed higher insulin-like growth factor-1(IGF-1) activity when compared with the Gh-199 group. Overall, the bone growth plate, femoral bone length, and bone mineral density measurements, and the blood analysis showed positive results in the group treated with Gh-199, and no specific toxicity of the herbal medicine in the body was evident.