High energy milling process에 의한 Gd₂O₃-doped CeO₂의 소결성 증진

최광훈,이주신 경성대학교 공학기술연구소 2003 공학기술연구지 Vol.S1 No.2

Gd₂O₃-doped CeO₂ powders with Ga₂O₃ addition were prepared by ball milling and high energy milling, respectively. The powders prepared by high energy milling showed the particle size of average 0.52 μm and narrow particle size distribution than ball milled powders. The specimens prepared by high energy milled powders showed higher sintered density than ball milled specimens. Also, the specimens containing 0.5 mol% Ga₂O₃ had the highest relative density of 97%, but it decreased with further addition of Ga₂O₃.. High energy milling process and Ga₂O₃ addition gave good effect on sinterability of Gd₂O₃-doped CeO₂.

Gd₂O₃doped CeO₂의 소결성에 미치는 Al₂O₃의 첨가효과

최광훈,이주신 경성대학교 공학기술연구소 2002 공학기술연구지 Vol.9 No.-

The effect of Al_2O_3 addition on sintering behavior of 10 mol% Gd_2O_3 doped CeO_2 was systematically investigated from the following aspects: the variation in sintering density, the variation in grain size, and the forms and existence position of Al_2O_3 in CeO_2. Sintering density increased up to 2 mol% Al_2O_3 addition, and then it decreased. Grain size increased up to 2 mol% Al_2O_3 addition also. Over 2 mol% Al_2O_3 addition, grain size was decreased by a pinning effect of AlGdO_3 precipitation at grain boundary. Lattice constant decreased with increasing Al_2O_3 content up to 2 mol%. This decrease will be due to the substitution of smaller Al^3+ ions for Ce^4+ ions in the CeO_2 structure. According to the result of SEM and XRD analysis, the solubility limit of Al_2O_3 in 10 mol% Gd_2O_3 doped CeO_2 can be estimated to be nearly 2 mol%. The addition of Al_2O_3 up to solubility limit was found to promote the sintering properties.

Strontium gallate의 첨가에 따른 Gd_(2)O_(3)-doped Ceo_(2) 세라믹스의 소결특성

최광훈,이주신 경성대학교 공학기술연구소 2004 공학기술연구지 Vol.11 No.-

The densification behavior of Ce_(0.8)Gd_(0.2)O_(1.9) ceramics was investigated with the strontium gallate concentration ranging from 0 to 5 mol%. Sintered density was the highest at the specimen containing 0.5 mol% Sr_(2)Ga_(2)O_(5). 0.5 mol% Sr_(2)Ga_(2)O_(5)-added specimen had the relative density of 97%. Overall, sintered density of specimens containing Sr_(2)Ga_(2)O_(5) was higher than that of pure specimen. Sr_(2)Ga_(2)O_(5) addition gave good effect on sinterability of Gd_(2)O_(3)-doped CeO_(2).

TetR-VP16-mediated transcription activation system에서 TetR-VR16과 TetR 이종dimer에 의한 전사활성의 영향

최광훈,김기호,김홍진 중앙대학교 약학연구소 1999 약학 논총 Vol.13 No.-

In TetR-VP16-mediated transcription activation stystem TetR-VP16 hobodimer activates the tet operator modified minimal promoter. To determine the effect of the heterodimer of TetR-VP16 on transcriptional activation from that minimal promoter cotransfection assays were performed with U373 cells. In coexpression of TetR-VP16 and TetR the expression from the minimal promoter was activated 4-12 fold higher than in expression of TetR-VP16, suggesting that the usage of the heterodimer of TetR-VP16 can improve the effecacy of TetR-VP16-mediated transcription activation system

브랜드 디자인의 시각적인 표현 요소에 관한 연구 : 영캐주얼 제품의 브랜드를 중심으로

최광훈 한국패키지디자인학회 2002 상품문화디자인학연구 Vol.11 No.-

Design can be said to be a kind of a language system. it is a basic form of a language that enables us to communicate thoughts and ideas to others before words can be formed to express them for talking and writing. Visual design may be a creative activity expressed in graphics aimed for human communication to take place, and to have it accomplished through visual representation. Lately a new type of consumer group possessing diversified needs has emerged in a rapidly changing environment of the fashion market. Competition is made fierce among those in fashion business to meet such needs. Particularly a group of young generation is quite different from their predecessore, and has become a dominant player determining the market position. With enormous purchasing power they actually lead the medium-and-low-priced market segment for unisex casual-clothes for the uoung. As society became more sophisticated, people found more needs to satisfy. Since needs thend to createtheir own supply, a variety of products came flowing into the market to meet such needs, which are most of the cases a product of carefully planned design work with meticulous attention to detail. Each product has its own image that may vary depending on color, type of product and brand. A brand may be one of the most powerful factors affecting the image of a given product. There are tens of thousands of fashion brands for each type of fashion design. However, it is common to see quite a number of similar looking brands. This is probably because people have similar idea of beauty, and they are inclined to pursue a symbolic design that best fits the purpose. It is therefore very important how one hives unique features to a brand he or she is designing. And how is he or she adjusting the brands readability? Those are two of the most important questions to ask when establishing a brand design strategy in view of purchasing behavior of the new generation. Business firms contemplating a brand design should not forget the fact that this new generation is just too important to be neglected and that they are actually a dominant power leading a social change in our society. It may be the first on the priority list of the business firm's action plan to understand this powerful new generation, which actually led the consumption pattern and created a new pattern centered around styling, individuality, and diversity. Communicating information through a brand can be both effective and extensive as it passes information through visual representation, and would most likely play an important role as far as the market share is concerned. it may be important to invent a brand image for the medium-and low-priced casuals that appeals to the sensitivity of this consumer group of young generation

테트라사이클린에 의한 HCMV에서 바이러스유전자 발현유도

최광훈,김기호,김홍진 중앙대학교 약학연구소 1998 약학 논총 Vol.12 No.-

Recombinant viruses containing the US11 gene under the control of the tet O-modified US11 promoter were isolated ; DNA blot analysis attested to the fidelity of the recombination Western blot experiment using polyclonal antisera of US11 gene product indicated that US11 gene expression of the recombinant virus was induced in the infected tTA expressing cell lines by the presence of tetracycline. This tetracycline-dependent inducible gene expression system has potential applications to study the biological roles of HCMV genes.

Gd₂O₃doped CeO₂에서의 Al₂O₃ 및 Ga₂O₃의 고용도한

최광훈,이주신 경성대학교 공학기술연구소 2002 공학기술연구지 Vol.9 No.-

The solid solubility limits of Al_2O_3 and Ga_2O_3 in Gd_2O_3 doped CeO_2 were determined by X-ray diffraction and scanning electron microscope measurements. The solubility limit of Al_2O_3 in Gd_2O_3 doped CeO_2 was found to be 2 mol%, and Ga_2O_3 was found to be 5 mol%. It is expected that the determination of the solid solubility limits will give an important information in a study on the promotion of the sintering properties with sintering aids addition.

생활하수슬러지가 토양 화학성 및 장미의 생육에 미치는 영향

최정,이동훈,박만,최충렬,김광섭 한국환경농학회 2002 한국환경농학회지 Vol.21 No.2

생활하수슬러지를 장미 재배지에 토양 개량제로서 시용량을 달리하여 첨가하고 장미의 생육상, 토양 및 식물체중 중금속의 함량에 미치는 영향을 조사하였다. 장미 재배지에 하수슬러지를 사용하면 시용량이 증가함에 따라 신장과 비대생장이 증가했으며 주당 꽃송이도 많아 생육이 양호한 것으로 나타났다. 토양 중 중금속 함량은 시용량의 증가에 따라 일정한 경향은 없었으며 식물체에 의한 대부분의 무기성부 흡수량은 하수 슬러지의 시용량에 따라 증가하는 것으로 나타났다. 결과적으로 생활 하수 슬러지는 유해물질의 농도가 낮으면 경작지에 처리하여도 무관할 것으로 판단된다. This study was conducted to find out the effect of municipal sewage sludge on the growth and heavy metal content of rose and soil chemical properties. Municipal sewage sludge was applied to soil at rate of 0, 3, 5, 10 and 15 ton/10a, the plant height, flower number and stem size of rose were found to be increase in the treatments of sewage sludge. Contents of mineral nutrients in rose stem were determined to be higher at municipal sewage sludge application plots than those of no application. But, there were not any significant increases of heavy metal contents in soil and rose stem with the sludge applications. From the results of this study, it is apparent that the application of municipal sewage sludge would not increase available heavy metals in soil.

膈下逐瘀湯과 膈下逐瘀湯合四君子湯의 抗癌 및 免疫調節作用에 關한 實驗的 硏究

崔昇勳,安圭錫,文濬典,高光錫 대한동의병리학회 1994 동의생리병리학회지 Vol.9 No.1

연구배경 : 암은 사망의 주요 원인이 되는 질환으로 매년 증가하고 있는 추세이다. 이에 mouse에 암을 유발하여, 약물치료를 시행함으로써 높은 치료효과를 거두는 한약제재를 개발하여 암의 치료에 기여하고 아울러 근본적인 예방치료에 대한 새로운 방법을 제시하고자 함. 방법 : 생쥐에 Sacroma 180을 이식하여 복강암을 유발하고 격하축어탕 및 격하축어탕합사군자탕을 투여하여 생명연장률과 B cell 및 T cell, 혈청항체가, 임파구증식반응, IL-2 생산능 및 자연살해페소의 활성도를 측정하였다. 결과 : 격하축어탕과 격하축어탕합사군자탕은 면역조절작용을 통한 항암효과가 있을 것으로 생각되며, 활혈거어제인 격하축어탕과 보기제인 사군자탕을 합방했을때, 그 효과가 증가되었다. In order to investigate the effects of Gyeokhachukeotang and Gyeokhachukeotang plus Sagunjatang on anti-tumor and immunodulatory reaction to the ICR and C57BL/6 mice which have abdominal tumor after Sarcoma-180 cells were transplanted, the extracts of herbal medicines above mentioned were orally administered to the mice for 21 days to observe the extention of survival duration of the mice, quantitation of T cells and B cells, productivitiy of interleukin-2, lymphocytes transformation, hemagglutinin titer and hemolysin titer and activity of splenic natural killer cells. The results are summarized as follows; 1. In the effect of life extention, the Gyeokhachukeotang-medicated mice group inclined to show extended duration of life, which is of no great significant difference and the mice group medicated with mixture of Gyeokhachukeotang plus Sagunjatang appeared to survive longer than the Gyeokhachukeotang-medicated mice group, which is not meaningful. 2. Considering T cell and B cell content, the Gyeokhachukeotang-medicated mice group had a meaningful increase in B cell (P<0.05) content, and the mice group medicated with the mixture of Gyeokhachukeotang plus Sagunjatang remarkably showed a significant increase in both T cell and B cell (P<0.01). 3. Considering serum antibody titer tended to increase in case of the Gyeokhachukeotang-medicated mice group, which is of no significant difference, while decreasing in case of the mice group medicated with mixture of Gyeokhachukeotang plus Sagunjatang. 4. In lymphocyte transformation marked a significant increase the Gyeokhachukeotang-medicated mice group, marked a significant (P<0.01), and remarkably showed a significant increase the mice group medicated with the mixture of Gyeokhachukeotang plus Sagunjatang (P<0.001). 5. As for the productivity of interleukin-2 and the activity of NK cells, the both tested groups inclined to show an increase or a decrese, but there is no significance.

치아의 순(협)설 경사도 변화에 따라 파노라마 방사선 사진에 나타난 치아 길이 및 각도 변화

최갑림,임성훈,김광원,김재덕 대한치과교정학회 2007 대한치과교정학회지 Vol.37 No.2

파노라마 방사선 사진은 치아 및 주위 조직에 대한 많은 정보를 제공해 주며 교정치료 동안에도 치근의 근원심 경사도나 길이 평가를 위해 흔히 이용되고 있지만 파노라마 방사선 사진에서 보이는 치아의 근원심 각도와 길이는 순(협)설 경사도에 의해 영향을 받는 것으로 알려져 있다. 따라서 본 연구에서는 치아의 근원심 경사도를 정상교합자의 평균 근원심 각도로 유지하면서 순(협)설 경사도만 변화시킬 때 파노라마 방사선 사진에서 각 치아의 근원심 경사도와 길이가 어떻게 변화되는지 알아보고자 하였다. 성인 정상 교합자 30명의 평균 악궁을 기초로 하여 아크릴 모델을 제작한 후 치아를 대신하는 와이어를 정상 근원심 및 순(협)설 경사도(I°)로 식립하고 여기에 순(협)설 경사도만 I-15°에서 I+15°까지 5°씩 변화시켜 파노라마 방사선 사진을 촬영한 후 방사선 사진에 나타난 와이어의 길이와 각도를 각각 계측하였다. 와이어를 정상 근원심 및 순(협)설 각도로 식립했을 때 방사선 사진에서 계측된 길이는 중절치, 측절치, 견치의 경우 실제 길이의 111% ~ 117%의 확대율을 보였고, 소구치와 대구치에서는 121% ~ 125%의 확대율을 보였다. 이 때 근원심 경사도는 그대로 유지하면서 순(협)설 경사도만 I-15°(순측경사)에서 I+15°(설측경사)로 변화시킨 경우 중절치 (p < 0.01)와 측절치 (p < 0.05)에서만 유의한 확대율 증가를 보였다. 파노라마 방사선 사진에서 치아의 경사도는 대부분 실제 근원심 경사도보다 더 크게 즉 원심경사된 것으로 계측되었고, 이러한 원심경사 경향은 측절치와 견치에서 가장 크게 나타났으며, 제1, 2소구치의 I+10°, I+15° 그룹과 제1, 2대구치의 I+15° 그룹에서만 실제 근원심 각도보다 더 작게, 즉 근심 경사된 것으로 계측되었다. 또한 순(협)설 경사도의 변화에 따라 파노라마 방사선 사진에서 모든 치아의 근원심 각도가 유의한 변화를 보였는데, 순(협)설 경사도가 작아질수록, 즉 순(협)측 경사될수록 파노라마 방사선 사진에서 더 원심경사되어 나타났다. 따라서 파노라마 방사선 사진에서 중절치와 측절치의 치아 길이와 모든 치아의 근원심 경사도를 평가할 때 치아의 순(협)설 경사도에 따라 영향을 받기 때문에 이를 고려해야 할 것이다. Objective: The purpose of this study was to examine how the mesio-distal angulation and the length of each tooth changes on panoramic radiograph at different bucco-lingual inclinations. Methods: After constructing an acrylic model based on the mean arch of 30 adults with normal occlusion, the wire was placed in the center of the teeth on the acrylic model. First, the wire was implanted in normal angulation and inclination and a panoramic radiograph taken. After changing the inclination from I-15° to I+15° by 5°, a panoramic radiograph was taken again and the mesio-distal angle and wire length on the panoramic radiograph were assessed. Results: When the wire was implanted at the normal angulation and inclination, the length measured in the panoramic radiograph was magnified 111 ~ 117% from the original length in the anterior region and 121 ~ 125% in the posterior region. Only the central and lateral incisors showed significant length differences when the inclination was changed from I-15° to I+15° at fixed angulation. When the inclination was changed from I-15° to I+15°, the angulation of most teeth on panoramic radiograph appeared to be more disto-angulated than in reality, and the lateral incisor and canine showed the largest difference. Only I-15°, I+15° groups of premolars and I+15° group of molars showed more mesio-angulation than in reality. As the labio(bucco)lingual inclination of all teeth were decreased, tooth angulation in the panoramic radiograph appeared to be more disto-angulated. Conclusion: The labio-liugual inclination of teeth should be considered because it affects panoramic image of teeth, such as length of incisors and angulation of other teeth.