대전 대덕구 출토 복식 유물에 부착된 세균의 종류 및 섬유소분해효소 활성

이상준,차미선,조현혹,백영미,권영숙 한국의류산업학회 2005 한국의류산업학회지 Vol.7 No.1

This study was aimed to isolation and identification of attached bacteria on the clothes excavated from Deajeon area dating on the 16th century. From the observation with colony shape, 17 bacterial strains were isolated, and then 7 bacterial strains were identified with morphological and biochemical characteristics. Streptococcus sp., Alcah eves faecalis, Gemella sp., Acinetobacter sp., Pseudomones vesicularis, Aeromonas sails. salmonicida, Moraxella spp. In observation of the bacterial strains by the sort of textile, more bacterial strains were found in silk, cotton, and cotton bats than in ramie and hemp. It is suggest that hemp has antibacterial characteristics due to the presence of lignin. In the comparison washed samples with unwashed ones, there were more kinds of bacterial strains in washed samples. In the cellulase activity tests, all isolated bacteria had low level cellulase activity.

(Bi_2O_3)_0.73(CaO)_0.27 세라믹 산소이온전도체의 저온에서의 전기전도 특성

李晟齊,盧鎭孝,白鉉德 홍익대학교 산업기술연구소 1996 産業技術 Vol.6 No.-

Low temperature characteristics of ionic conduction in (Bi_2O_3)_0.73(CaO)_0.27 ceramics were investigated by ac impedance analysis. In the 200 to 500℃ temperature range grain boundary effect was not separated in the impedance plane. The speciments with larger grain size exhibited higher electrical conductivity and lower activation energy than deternined to be 101 kJ/mol, which was very close to the reported value, 106 kJ/mol. At 300℃ and lower temperatures conductivity curve bent toward higher conductivity, as was reported in the some other ion conducrors. The conductivity showed aging effect at temperatures lower than 350℃, but conductivity decrease was not significant.

피압수가 존재하는 연약점토지반 내에 연직배수재의 관입깊이에 따라 압밀거동에 미치는 영향

정성교,진현식,백승훈 동아대학교 건설기술연구소 1999 硏究報告 Vol.22 No.2

In the Yangsan area developed for housing complex the soft clay deposited as about 20 to 40 meters in thickness and there was the Artesian pressure of about 20kPa under the clay stratum. To investigate the consolidation behaviour due to partially or fully penetrating vertical drains in the clay layer, a finite element analysis was carried out in this study. As a result of analysis, it was shown that the consolidation rate and the final settlement for the case of fully penetrating vertical drains were faster and less than of partially penetration, respectively.

SS400강판 맞대기용접부의 Out-of-plane 변위측정

차용훈,성백섭,김덕중,김성현,김충환 朝鮮大學校 機械技術硏究所 2002 機械技術硏究 Vol.5 No.1

Currently knowledge of strain in welds has mainly been obtained from strain gaging method which is directly attaching the gage to most of the material. The few non-contact method are still in the early stage. One of the non-contact methods is the use of the laser that has high-level of the accuracy for the measurement, and this laser also has excellent characteristics on which many studies for its applications are focused in the lot of fields. This study is focused on the measurement of the displacement caused by the characteristics and the temperature change of the CO2 welded zone which is used with 3-D ESPI (Electronic Speckle Pattern Interferometry) system that is functionally modified the laser ESPI system. This system employed the SS400 which are mainly used for the steel plate such as general welded structure, bridge, industrial machine and especially using structure of the Absorption Chiller-Heater.

단열양생을 이용한 고강도 콘크리트 압축강도 추정에 관한 실험적 연구

조규현,김제섭,전판근,백민수,김우재,정상진 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1(구조계)

The present study is a basic experiment on the estimation of the compressive strength of high strength concrete, aiming at estimating the compression strength of mass test pieces of high strength concrete by giving the temperature hysteresis of the mass test pieces to managerial test pieces. Different from ordinary concrete, high strength concrete generally shows the high rise of temperature caused by hydration heat inside the concrete. It is known that, in mass concrete, thermal stress occurs due to the difference in temperature between the inside and the outside, which causes a significant difference in compression strength between structure beams and managerial test pieces. It is also reported that there is a large difference between the compression strength of cylindrical managerial test pieces of standard underwater curing and the strength of structure beam concrete. Thus, this study made concrete test pieces in an optimal mix ratio for each strength level, and also created adiabatic curing tank and managerial test pieces. Then it carried out comparative analysis in relation to core strength and suggested equipment and a technique that can control the strength of high strength concrete mass more conveniently and accurately.

기저세포암 및 편평세포암에서 미세혈관밀도와 p53 단백 발현에 관한 연구

어수락,조규성,안호범,김대영,이삼용,조백현 大韓成形外科學會 1999 Archives of Plastic Surgery Vol.26 No.3

Basal cell carcinoma(BCC) and squamous cell carcinoma (SCC) are very prevalent neoplasms of the human skin. Ultraviolet radiation in sunlight is a well-established mutagen of the p53 gene and is one of basal cell carcinoma and squamous cell carcinoma. The newly-formed vascular network is important for neoplasms to grow beyond a size of about 1 ㎣. Recent reports have suggested the hypothesis that a mutant p53 protein is closely related with capillary density. Immumohistochemistry for p53 protein and CD34 was performed in 20 cases of BCCs and 14 SCCs to evaluated the relationship between p53 protein and capillary density. The results were as follows:1. The microvessels stained by CD34 were mainly located in the interface of tumor cells and stroma. 2. There was no difference in the microvessel density according to the histologic types and age of the patients, but a higher microvessel density was noted in male patients. 3. The aggressive BCCs and the less-differentiated SCCs showed higher p53 immunostaining. 4. The mean microvessel density of cases showing strong positive immunostaining of the p53 gene(54.73±17.75) was higher than that of others(39.75±18.30). These results suggested that p53 protein expression and microvessel density are not related to the histologic types and age of the patients, but that differentiation and biologic behavior such as the infiltrating property of tumors and the microvessel density are closely related to p53 protein expression.

유전치의 polyethylene fiber-post를 이용한 심미수복에 관한 증례 보고

서영주,조태식,김효석,고승백,정현구,이난영 조선대학교 구강생물학연구소 2002 口腔生物學硏究 Vol.26 No.2

In clinical practice, restoration of primary incisors severely affected by caries continues to be a challenge. Not only are these teeth difficult to restore. but the behavior of the patient can affect treatment negatively. An acceptable restoration for maxillary anterior incisors should have matching material color, durability, adhesive cementation that is biocompatible with the pulp, easily and rapidly placed. This Paper describes two cases showing an alternative technique for the construction of completely destroyed upper incisors with polyethylene ribbons for retention and stability for the resin crowns.

Seedling Stand Influenced by Water Management after Seeding and Seed Soaking with Plant Growth Regulators in Direct Wet Seeding Rice

Back, Nam-Hyun,Kim, Sang-Su,Kang, Si-Yong,Choi, Min-Gyu,Shin, Hyun-Tak,Kwon, Tae-Oh The Korean Society of Crop Science 1999 Korean journal of crop science Vol.44 No.3

Unstable seedling stand establishment of wet direct seeding culture of rice is one of the major elements preventing the extension of its culture area. In order to develop methods of seedling stand improvement in direct seeded rice on flooded surfaces, three field experiments were conducted on silty loam soil using a cultivar 'Donjinbyeo' for three years, mainly focusing on water management after seeding and seed soaking with plant growth regulators (PGRs). Under the condition of shallow flooding after seeding, seedling stand rate increased and floating seedling rate decreased in both early and normal season seeding compared to deep flooding. With earlier draining time after seeding, there was a tendency towards preferential growth of the seminal root, increase of seedling stand and decrease of the floating seedling rate. Therefore the highest seedling numbers per unit area and the lowest floating seedling numbers were found upon drainage at 1 day after seeding (DAS), while a contrary tendency was shown upon conventional drainage at 7 DAS. Seed soaking with PGRs such as Metalaxyl or mixing of Metalaxyl with gibberellic acid (GA$_3$) significantly increased the seedling stand. In addition the effects of PGR treatment on seedling stand and the early growth of plants were greater under flooded conditions than under drained conditions after seeding, although draining of water after seeding improved the seedling establishment rate more when compared with the PGR treatment. These results suggest that draining management after seeding or maintaining of shallow flooding for a week is the most effective method to improve the seedling stand rate in wet direct seeding.

지역사회 노인의 인지기능과 정신적 활동의 연관성

여현철(Hyun Chul Yuh),고상현(Sang Hyun Koh),이윤환(Yunhwan Lee),백종환(Joung Hwan Back),임기영(Ki Young Lim),김현정(Hyun Chung Kim),홍창형(Chang Hyung Hong) 대한노인정신의학회 2011 노인정신의학 Vol.15 No.1

Objectives:The purpose of this study was to describe the status of mental activity participation in community-dwelling elderly and to evaluate the association between mental activity and cognitive function after adjustment for depression and anxiety. Methods:This study was based on the Suwon Project, which was a cohort comprising of nonrandom convenience samples of ethnic Koreans aged 60 years and above. All the subjects completed the study questionnaire including their demographic characteristics, current and past illnesses history, drug history, Korean version-Mini Mental State Examination (K-MMSE), Korean version of Short Form Geriatric Depression Scale (SGDS-K), Beck Anxiety Inventory (BAI). We checked how many hours per day are used for each items of 11 mental activities through the checklist. Results:Total time spent in 11 mental activities was 237.4±152.4 minutes per day. On multiple regression analysis, total time spent in 11 mental activities (MA-total), and time spent by watching television and reading book/newspaper showed statistically significant association with K-MMSE score after adjustment with age, sex, education, chronic medical illness, depression and anxiety. Conclusion:Our result suggested that mental activity may be associated with cognitive function in the elderly without cognitive impairment in the community after adjusting age, sex, education, chronic medical illness, depression and anxiety.

DOT 색인을 이용한 효율적인 공간 조인 기법

백현(Hyun Back),윤지희(Jee-Hee Yoon),원정임(Jung-Im Won),박상현(Sang-Hyun Park) 한국정보과학회 2007 정보과학회논문지 : 데이타베이스 Vol.34 No.5

지리정보시스템에서 빈번히 사용되는 공간 조인 연산자의 성능을 보장하기 위해서는 효율적인 색인 기법의 선택이 중요하며, 대표적인 색인 기법으로는 R<SUP>*</SUP>-tree를 이용한 방법이 알려져 있다. 본 논문에서는 DOT(DOuble Transformation) 공간 색인을 이용한 효율적인 공간 조인 처리 기법을 제시하고 이를 R<SUP>*</SUP>-tree를 이용한 공간 조인 처리 기법과 비교한다. DOT 공간 색인 기법은 공간 객체의 MBR 정보를 공간 순서화 곡선을 사용하여 하나의 1차원 값으로 변환한 후 그 값을 검색 키로 갖는 B<SUP>+</SUP>-tree 색인 구조를 구성하는 방법으로서, 이를 이용하면 전통적인 데이타베이스의 주 색인을 적용할 수 있다는 중요한 특징을 가진다. 본 논문에서는 공간 객체의 MBR 정보를 하나의 1차원 값으로 변환하기 위해 사용되는 공간 순서화 곡선의 규칙성을 분석함으로써 공간 변환 연산의 횟수를 대폭 감소시킨 효율적인 DOT 색인 기반의 공간 조인 알고리즘을 제안한다. 제안된 알고리즘에서는 반복적으로 수행되는 공간 변환 연산의 횟수를 줄이기 위하여 질의 영역을 공간 순서화 곡선이 연속 운행하는 가능한 최대 크기의 면적으로 분할하는 쿼터 분할 기법을 사용한다. 다양한 분포와 크기를 갖는 데이타 집합을 대상으로 R<SUP>*</SUP>-tree를 이용한 공간 조인 처리 기법과의 비교 실험을 수행한 결과 최대 약 3배의 성능 이익을 얻을 수 있음을 확인할 수 있었다. The choice of an effective indexing method is crucial to guarantee the performance of the spatial join operator which is heavily used in geographical information systems. The R<SUP>*</SUP>-tree based method is renowned as one of the most representative indexing methods. In this paper, we propose an efficient spatial join technique based on the DOT(DOuble Transformation) index, and compare it with the spatial join technique based on the R*-tree index. The DOT index transforms the MBR of an spatial object into a single numeric value using a space filling curve, and builds the B<SUP>+</SUP>-tree from a set of numeric values transformed as such. The DOT index is possible to be employed as a primary index for spatial objects. The proposed spatial join technique exploits the regularities in the moving patterns of space filling curves to divide a query region into a set of maximal sub-regions within which space filling curves traverse without interruption. Such division reduces the number of spatial transformations required to perform the spatial join and thus improves the performance of join processing. The experiments with the data sets of various distributions and sizes revealed that the proposed join technique is up to three times faster than the spatial join method based on the R<SUP>*</SUP>-tree index.