가변적층쾌속조형시스템에 대한 연구

정동원,한유리,고형훈 제주대학교 공과대학 첨단기술연구소 2005 尖端技術硏究所論文集 Vol.16 No.1

Today, product a model is diversified according to consumer various request, and product development period and beginning period and cost saving are urgently required. High speed modeling system can serve to reduce expense and time. That is required in product development that product arrived from design to prototype production to cope effectively with a market's request. In this paper, studied to supplement problems to use VLM-ST to solve problem of modeling time of long hours, high price's device induction and preservation etc. that is problem of that do existent rapid prototyping system.

미니 임플란트 직경에 따른 피로파절강도의 비교 연구

허유리,손미경,김희중,최한철,정재헌 大韓齒科補綴學會 2012 대한치과보철학회지 Vol.50 No.3

Purpose: This study was conducted to obtain difference in fracture strength according to the diameter of one-body O-ring-type of mini implant fixture, to determine the resistance of mini implant to masticatory pressure, and to examine whether overdenture using O-ring type mini implant is clinically usable to maxillary and mandibular edentulous patients. Materials and methods: For this study, 13 mm long one body O-ring-type mini implants of different diameters (2.0 mm, 2.5 mm and 3.0 mm) (Dentis, Daegu, Korea) were prepared, 5 for each diameter. The sample was placed at 30 from the horizontal surface on the universal testing machine, and off-axis loading was applied until permanent deformation occurred and the load was taken as maximum compressive strength. The mean value of the 5 samples was calculated, and the compressive strength of implant fixture was compared according to diameter. In addition, we prepared 3 samples for each diameter, and applied loading equal to 80%, 60% and 40% of the compressive strength until fracture occurred. Then, we measured the cycle number on fracture and analyzed fatigue fracture for each diameter. Additionally, we measured the cycle number on fracture that occurred when a load of 43 N, which is the average masticatory force of complete denture, was applied. The difference on compressive strength between each group was tested statistically using one-way ANOVA test. Results: Compressive strength according to the diameter of mini implant was 101.5 ± 14.6 N, 149 ± 6.1 N and 276.0 ± 13.4 N, respectively, for diameters 2.0 mm, 2.5 mm and 3.0 mm. In the results of fatigue fracture test at 43 N, fracture did not occur until 2×106 cycles at diameter 2.0 mm, and until 5×106 cycles at 2.5 mm and 3.0 mm. Conclusion: Compressive strength increased significantly with increasing diameter of mini implant. In the results of fatigue fracture test conducted under the average masticatory force of complete denture, fracture did not occur at any of the three diameters. All of the three diameters are usable for supporting overdenture in maxillary and mandibular edentulous patients, but considering that the highest masticatory force of complete denture is 157 N, caution should be used in case diameter 2.0 mm or 2.5 mm is used. 연구 목적: 일체형의 o-ring type 미니 임플란트 고정체의 직경에 따른 파절강도의 차이를 비교하고자 한다. 연구 재료 및 방법: 길이 13 mm의 one body o-ring type의 미니 임플란트(Dentis, Daegu, Korea)를 직경2.0, 2.5, 3.0 mm 각각 5개씩 준비하였다. Instron universal testing machine 에 수직면에서 30도 각도로 샘플을 위치시키고 off-axis loading을 가하여 영구변형이 일어난 하중 값을 파절강도로 하고 5개의 시편의 평균을 구하여 각 직경에 따른 임플란트의 고정체의 파절강도를 비교하였다. 또한, 각 직경마다 3개의 시편을 준비하고 동적하중 피로 시험기를 이용하여, 파절이 발생할 때까지 파절강도의 80%, 60%, 40%의 loading 을 가하여 파절되는 cycle수를 측정하여 각 직경의 피로 파절을 분석하였다. 추가적으로 총의치의 평균 저작력인 43 N의 하중을 가하여 파절되는 cycle 수를 측정하였다. 각 군간의 차이를 검증하기 위해서 일원분산분석(one-way ANOVA test)을 시행하였고, 통계처리는 SPSS ver.12 (SPSS Inc. Chicago, IL, USA) 을 이용하여 실시하였다. 결과: 직경 3.0 mm 의 미니 임플란트는 평균 276.0 ± 13.4 N의 압축력을 받았을 때 영구 변형이 일어났고 직경 2.5 mm 미니 임플란트가 149.0 ± 6.1 N, 2.0 mm 미니 임플란트가 101.5 ± 14.6 N일 때 영구 변형이 일어났다. 각 군간의 파절강도에는 유의한 차이가 있었다(P<.001). 총의치의 평균 저작력 하중에서 실시한 피로 파절 실험 결과, 세직경 모두 5×106 cycle까지 파절이 일어나지 않았다. 결론: 미니 임플란트의 정적 하중 하에서 최대 압축강도는 직경이 증가할수록 유의적으로 증가하였다. 최대 압축강도는 세 직경 모두 총의치의 평균 저작력 보다는 크나 최대 교합력보다는 직경 3.0 mm에서만 크게 나타났다. 총의치의 평균 저작력 하중에서 실시한 피로 파절 실험 결과, 세 직경 모두 파절이 일어나지 않았다.

임용 후보자 선정 경쟁시험에 대한 초등 특수교사의 인식 및 개선 요구

정평강,김유리 이화여자대학교 교과교육연구소 2017 교과교육학연구 Vol.21 No.4

본 연구의 목적은 초등 특수교사를 선발하는 임용시험에 대한 초등 특수교사의 인식 및 요구를 알아보고, 이를 토대로 초등 특수교사 임용제도가 역량 있는 특수교사를 선발하는 타당한 절차로 정착되는 데 필요한 기초 자료를 제공하는 데 있다. 이를 위해 임용시험을 통해 국·공립학교에 배치되어 근무하고 있는 초등 특수교사 9명을 대상으로 개별 심층면담을 실시하였으며, 면담자료는 연속적 비교분석법을 이용하여 분석되었다. 분석 결과 임용시험의 타당성, 개선요구라는 대주제 2개가 도출되었으며 대주제별로 하위주제 3개씩 총 6개의 하위주제가 드러났다. 연구결과를 바탕으로 초등 특수교사 임용시험을 개선하기 위한 시사점이 논의되었으며, 이와 함께 후속연구를 위한 제언이 제시되었다. 초등 특수교사의 관점에서 바라본 초등 임용시험에 대한 더 깊은 이해는 앞으로 임용시험 문항의 내용이나 절차, 제도를 개선하는 데 중요한 기초 자료를 제공할 것으로 사료된다 The purpose of the present study was to explore the perceptions of elementary special education teachers on the national teacher exam. In-depth interviews were conducted with each of the 9 elementary special teachers and the interview data were analyzed using the constant comparative method. Two main themes and 6 sub-themes emerged from the data analysis. Based on the findings, practical implications on how to improve the national teacher exam are discussed and future areas for research are suggested. A better understanding of the teacher exam based on perspectives of elementary special teachers seems to provide essential basic information that assists the improvement of its process and systems.

운동에 의한 뇌 활성과 인지기능에 대한 고찰

김경애,정유진,안나리,장혁기 서울여자대학교 자연과학연구소 2013 자연과학연구논문집 Vol.25 No.-

We reviewed literatures on human brain activity on exercise. It was proved that exercise activate brain function through various equipments. Among methods to evaluate brain activation, there are Electroencephalography (EEG), Magnetoencephalography (MEG), transcranial doppler sonography (TCD), Magnetic resonance imaging (MRI), Near Infrared Spectroscopy (NIRS) methods. There were different characteries in each measurement methods to demonstrate exercise effects. NIRS is a spectroscopic method that uses the near infrared region of the electromagnetic spectrum. According to using brain scanning equipments involved NIRS, moderate exercise increased frontal lobe (specially prefrontal cortex) and improves cognitive performance. This review will be discussed about brain activation and cognitive functions.

P284 : Facial angiofibromas treated with a combination of fractional resurfacing and topical rapamycin

( Yu Na Lee ),( Min Jung Kim ),( Hae Jeong Youn ),( Soo Young Kim ),( Nam Kyung Roh ),( Ho Jung Jung ),( Yu Ri Kim ),( Jae Wook Jung ),( Yang Won Lee ),( Yong Beom Choe ),( Kyu Joong Ahn ) 대한피부과학회 2014 대한피부과학회 학술발표대회집 Vol.66 No.1

New-onset of palmoplantar pustulosis while on adalimumab treatment for ankylosing spondylitis

( Yu Na Lee ),( Ho Jung Jung ),( Yu Ri Kim ),( Jae Wook Jung ),( Hyun Jung Park ),( Hyung Jin Hahn ),( Young Ji Hwang ),( Ji Young Kim ),( Yang Won Lee ),( Yong Beom Choe ),( Kyu Joong Ahn ) 대한피부과학회 2012 대한피부과학회 학술발표대회집 Vol.64 No.1

P135 : Analysis of the safety and efficacy of three natural extracts in cosmetics

( Yu Na Lee ),( Hae Jeong Youn ),( Min Jung Kim ),( Soo Young Kim ),( Nam Kyung Roh ),( Ho Jung Jung ),( Yu Ri Kim ),( Jae Wook Jung ),( Yang Won Lee ),( Yong Beom Choe ),( Kyu Joong Ahn ) 대한피부과학회 2014 대한피부과학회 학술발표대회집 Vol.66 No.2

Background: The function of sebum in human is reducing water loss from the skin``s surface and protecting the skin from infection by microorganism. However, when there is excessive secretion of sebum, it will cause black heads and expansion of the pores so that waste will be accumulated. Objectives: To develop cosmetics for sebum removal and pore improvement that can improve limitations of the existing products. The ingredients include Diospyros kaki (D. kaki ), Castanea crenata (C. crenata), and Polygonum cuspidatum (P. cuspidatum) and to verify the safety and human efficacy evaluation. Methods: Bacteria microbial limit test and patch test performed with 31 participants. Also, with 23 participants who have oily skin, efficacy evaluation was performed. Changes in the amount of sebum, moisture, dead skin condition, blackhead, skin roughness between before and after the test were compared for control group. Results: As a result of safety assessment, there was no pathogenic microorganism for microbial limit test and, there was no skin reactions for patch test. For changes in the amount of sebum and black head from efficacy evaluation,there was temporary improvement for the experimental group. For the amount of moisture, dead skin, and skin roughness of the experimental group showed improvement. Conclusion: When being complemented with body application test for long-term usage, they can be used as natural ingredients when cosmetic manufacturers or sellers are developing new products.

Integrin α6β4-Src-AKT signaling induces cellular senescence by counteracting apoptosis in irradiated tumor cells and tissues

Jung, Seung Hee,Lee, Minyoung,Park, Hyun A,Lee, Hyung Chul,Kang, Donghee,Hwang, Hyun Jung,Park, Chanho,Yu, Dong-Min,Jung, Yu Ri,Hong, Mi-Na,Kim, Yong-Nyun,Park, Heon Joo,Ko, Young-Gyu,Lee, Jae-Seon Springer Science and Business Media LLC 2019 CELL DEATH AND DIFFERENTIATION Vol.26 No.2

Genotoxicity Test on 3,9-Diferuloyl-6-oxopterocarpen, a New Agent Candidate for Anti-aging Material

Yu-Ri Jung,Sung-Min Park,Nam-Jin Lee,Hyeong-Bae Pyo,Geun Soo Kim,Jong-Hun You,Chun-Mei Lin,Zheng Mei Shu,Jong-Koo Kang 한국실험동물학회 2008 Laboratory Animal Research Vol.24 No.1

To perform the safety studies on 3,9-diferuloyl-6-oxopterocarpen (DFO), we accomplished the reverse mutation assay in Salmonella typhimurium and Escherichia coli, in vitro chromosomal aberration assay on Chinese hamster lung cell and in vivo bone marrow micronucleus test in male ICR mice. In the reverse mutation assay, this material treatment at the dose range up to 5,000 ㎍/plate did not induce mutagenicity in Salmonella typhimurium TA98, TA100, TA1535, TA1537 and in Escherichia coli WP2uvrA-with and without metabolic activation. In the in vitro chromosomal aberration assay, this material did not increase the number of cells having structural or numerical chromosome aberration. In the in vivo bone marrow micronucleus assay, no significant increase in the occurrence of micronucleated polychromatic erythrocytes was observed in male ICR mice administered this material. In conclusion, we suggested that DFO have no genotoxicity in reverse mutation assay, in vitro chromosomal aberration assay and in vivo bone marrow micronucleus test.

Catalytic Conversion of 1,2-Dichlorobenzene Over Mesoporous V₂O₅/TiO₂ Prepared from Spray Pyrolysis

Jung, Kyeong Youl,Jung, Yu Ri,Jeon, Jong-Ki,Kim, Jung Hwan,Park, Young-Kwon American Scientific Publishers 2011 Journal of nanoscience and nanotechnology Vol.11 No.2

<P>Mesoporous V2O5/TiO2 particles were prepared by spray pyrolysis and applied to the catalytic oxidation of 1,2-dichlorobenzene (1,2-DCB). Two different precursors (alkoxide and nanoparticles) for the TiO2 support were used to determine the effects on the texture properties and the catalytic activity of the mesoporous V2O5/TiO2 particles. The 5 wt% V2O5/TiO2 particles had the largest surface area (173 m2/g) and 4.7 nm in average pore size. The catalytic activity of the V2O5/TiO2 particles depended strongly on the loading quantity of vanadium, whereas the P25-derived samples showed no significant change in catalytic activity with weight% of vanadium. The surface area of the V2O5/TiO2 particles prepared using the alkoxide precursor was larger than that of the particles prepared using P25 nanoparticles. The P25-derived V2O5/TiO2 particles, however, showed a higher catalytic activity compared with those alkoxide-derived, which is due to the difference in the vanadium quantity exposed to the pore surface. It was confirmed that the 10 wt% V2O5/TiO2 particles prepared by spray pyrolysis had an excellent activity for the oxidation of 1,2-DCB, particularly at temperatures below 300 degrees C.</P>