• 제목/요약/키워드: 김상석

검색결과 148건 처리시간 0.029초

Streptomyces melanosporofaciens가 생산하는 새로운 항생물질 I. 생산균의 분류 . 동정 (New Antibiotics Produced by SEreptomyces mekmosporofaciens I. Taxonomy of the producing microorganism)

  • 김시관;김상석;김창한
    • 한국미생물·생명공학회지
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    • 제18권6호
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    • pp.624-632
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    • 1990
  • 새로운 phthalic acid 유도체 및 염기성 마크로라이드 항생물질을 생산하는 strain 88-GT-161은 numerical taxonomic data base에 의거 Streptomyces melanosporofaciens로 동정되었으나, 139 단위 특성 중 4가지 단위에 있어. S.violaceoniger 혹은 S.violaceusniger로 대표되는 cluster No.32에 속하는 6균주의 공통된 특성과 분명히 다른 특성을 나타냈다. 따라서 본 논문에서는 strain 88-GT-161의 분류. 동정학적 특성에 대하여 보고하고자 한다.

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이중 보안 레벨 기반의 다단계 관계형 모형 (Multilevel Relational Model based on Double Security Model)

  • 김상석;김응모
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2000년도 추계학술발표논문집 (상)
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    • pp.121-124
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    • 2000
  • DAC 정책을 기반으로 하는 DBMS에서 데이터에 대한 사용자의 접근 통제는 접근 규칙 데이터베이스에 저장된 접근 규칙을 바탕으로 이 사용자가 접근하려는 데이터에 접근 권리가 명시적으로 기술되었는지를 확인하므로 써 수행된다. MAC 정책은 각 시스템의 주체와 객체에게 보안 등급을 부여하고, 등급별로 분리된 정보의 보안을 유지하기 위해서 다중 보안 단계에서 정보를 처리하는 강제적 접근 권한을 제공한다. 본 논문에서는 실제 MAC 정책을 기업 환경에 적용시키는데 있어서는 많은 제약사항이 존재하고 있으며, 이러한 제약사항 중에 레벨별로 정보의 공유가 필요할 경우에 레벨간에 최대, 최소를 둠으로써 레벨간의 정보 공유를 가능하게 만들고자 하는 모델을 제안하고자 한다.

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웹 구조(構造)를 이용(利用)한 웹 질의(質疑) 시스템의 설계(設計) 및 구현(具現) (Design and implementation of Web Query System Using Web Structure)

  • 고성준;김상석;김응모
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2000년도 제13회 춘계학술대회 및 임시총회 학술발표 논문집
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    • pp.260-265
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    • 2000
  • 사용자 질의를 통한 검색엔진의 도움 없이 웹 데이터베이스의 개념을 도입하여, 웹을 직접 검색할 수 있는 웹 질의 엔진(Web Query Engine)을 제안한다. 특히 사용자가 자신이 원하는 질의를 할 수 있도록 기존의 질의 언어와 유사한 웹 질의 언어를 설계하고, 설계되어진 질의 언어를 사용하여 인덱스 서버에 정보의 요청 없이 네트워크 구조와 위상 기반의 질의를 할 수 있도록 하는 웹 질의 엔진을 설계 및 구현을 하였다.

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건설현장 활용을 위한 GIS기반의 국가지반정보DB 고찰 (Consideration of National Geotechnical Information Database based on GIS for application to construction sites)

  • 김상석;장용구;강호윤;강인준
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2007년도 춘계학술발표회 논문집
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    • pp.399-402
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    • 2007
  • National Geotechnical Information Database Project based on GIS has begun as public works and continued until now, the whole of country has been target on since the 2003. Today, the 60,581 number of geotechnical data(counted by bering number) have been constructed as GIS-DB and they are being serviced at the National Geotechnical Information Integration Management System(NGIIMS)(http://www.geoinfo.or.kr). In this study, we considered operation status of NGIIMS, GIS-DB distribution of Geotechnical Information and utilization in order to investgate applicability of National Geotechnical Information Database. The results appeared that Geotechnical Information DB was along road-center, and in the case of complex, was only to some area. But after the 2007 when the law of computerization responsibility would be institutionalized, the more geotechnical data will be constructed and be able to use at a construction site.

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담배나방(Helicoverpa assulta: 인시목 밤나방과)의 정자형성 과정과 염색체수 (Spermatogenesis and Chromosome Number of the Tobacco Budworm Helicoverpa assulta Guenee (Lepidoptera: Noctuidae))

  • 유종명;정성은;박희윤;채순용;김상석
    • 한국연초학회지
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    • 제18권1호
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    • pp.12-20
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    • 1996
  • The spermatogenesis and chromosome number were investigated in the pupal testes of Helicouerpa assulta Guenee by light microscopy. During the spermatogenesis, each bundle of P8(256) sperms developed by 6 mitotic and 2 meiotic spermatogonial divisions. From the early stage of spermatogenesis, it was distinguishable between two kinds of sperm differentiation, eupyrene and apyrene spermatogenesis, which are characteristic in Lepidoptera, by the differences in nuclear shape and cell distribution in immature spermatocyst. Through the followed spermiogenesis, the spermatocysts were developed into two kinds of mature cyst, a streamline-shaped eupyrene cyst with nucleated sperms of thready head or a long spindle-shaped apyrene cyst with anucleated sperms of cylindrical head. As the results off chromosomal analysis at metaphase of the spermatogonial mitosis and spermatocytic meiosis, the chromosome number were 2n=6a/n=31, respectively, and no variation between individuals.

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레이저 빔 프린터용 F-theta Lens 개발 (Development of F-theta Lens for Laser Beam Printer)

  • 김상석;김현욱;정상화;김혜정;김정호
    • 한국전기전자재료학회논문지
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    • 제19권4호
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    • pp.386-390
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    • 2006
  • Global consumption of aspheric lens will expand rapidly due to golbal transformation of the electronics based industry to optics based mechatronics. Especially, F-Theta lens is one of important parts in Laser Scanning Unit(LSU) because it affects the optical performance of LSU dominantly. Non axisymmetric machine based processing techologies are required to obtain high accuracy in utlra-precision aspheric core, the most important component in plastic injection molded F-Theta lens assembly. In this study, the core with non-axisymmetric aspheric shape which is used to emit the F-Theta lens was processed using the ultra precision processing technology and the shape accuracy of the core was measured. And the results there of were evaluated and compared with the emitted shape accuracy of F-Theta lens.

초정밀가공기를 이용한 알루미늄반사경의 절삭특성 (A Study of Aluminum reflector manufacturing in diamond turning machine)

  • 김건희;도철진;홍권희;유병주;원종호;김상석
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2001년도 춘계학술대회 논문집
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    • pp.1125-1128
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    • 2001
  • A 110mm diameter aspheric metal secondary mirror for a test model of an earth observation satellite camera was fabricated by ultra-precision single point diamond turning(SPDT). Aluminum alloy for mirror substrates is known to be easily machinable, but not polishable due to its ductility. A harder material, Ni, is usually electrolessly coated on an Al substrate to increase the surface hardness for optical polishing. Aspheric metal secondary mirror without a conventional polishing process, the surface roughness of Ra=10nm, and the form error of Ra=λ/12(λ=632nm) has been required. The purpose of this research is to find the optimum machining conditions for reflector cutting of electroless-Ni coated Al alloy and apply the SPDT technique to the manufacturing of ultra precision optical components of metal aspheric reflector.

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다기능 복합가공기의 틸팅터릿 시스템의 진동특성 해석 (Dynamic Characteristics of the Tilting Turret System for Multi-Purpose Lathe)

  • 정상화;김상석
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 추계학술대회 논문집
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    • pp.215-219
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    • 2000
  • In multi-purpose lathe, the design of tilting turret slide system has on important and critical role enhance accuracy of the machining process. Tilting turret unit is traveled by 3-axis slide systems. There is a need to design this part very carefully. In this research, 3-axis sliding system with tilting turret is modeled by considering the element dividing, material proprties, and boundary conditions using MSC/PATRAN. Mode and frequency analysis of each structures such as saddle, careg, and turret are simulated by MSC/MASTRAN, for the purpose of developing the effective design.

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연초포장에서 발생하는 복숭아혹진딧물(Myzus persicae Sulz.)의 Esterase 분류

  • 채순용;김상석;정성은;장영덕
    • 한국연초학회지
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    • 제21권1호
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    • pp.49-56
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    • 1999
  • Classification of esterase isozymes of the apterous green peach aphids (Myzus persicae Sulzer) collected in tobacco fields were investigated by the native polyacrylamide gel electrophoresis (PAGE). A total of twelve esterase bands were identified in adult apterous aphid, and the difference of enzyme band activity in the clones was observed at the first and second bands group. Esterases of green peach aphids reacted with specific substrate were more stained $\alpha$-naphthyl acetate than $\alpha$-naphthyl propionate, and $\alpha$-naphthyl acetate more than $\beta$-naphthyl acetate. Twelve esterases on the basis of inhibition by the three types of inhibitors (organophosphates: 2.5$\times$10$^{-3}$ M paraoxon, 4$\times$10$^{-3}$ M DFP; eserine sulfate : 2$\times$10$^{-3}$ M eserin; sulfhydryl reagents: 2$\times$10$^{-3}$ M p-HMB) were classified into three class, namely, cholinesterase (ChE) I, II, carboxylesterase (CE) and arylesterase (ArE), and these classes contained 3, 4, 3 and 2 isozymes, respectively.

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연초포장에서 발생하는 복숭아혹진딧물의 핵형과 살충제 저항성 (Karyotype and Insecticide Resistance of the Green Peach Aphids (Myzus persicae Sulzer) collected from Tobacco fields)

  • 채순용;김영호;김상석;장영덕
    • 한국연초학회지
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    • 제19권2호
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    • pp.107-116
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    • 1997
  • Karyotype of apterous green peach aphid (Myzus persicae SuIBer) populations occurring in tobacco fields and their resistance to insecticides were investigated. All of the 16 clones collected from tobacco fields had same chromosome number of 2n=12. Among them, 5 clones had the normal karyotype, regardless of color morph, but chromosomal translnations between #1 and #3 autosomal chromosomes were noted in the other 11 clones. All of the aphid clones were highly resistant tolambda cyhalothrin, a pyrethroid pesticide, having over 20 times higher concentrations of LD90 than recommended concentration (10ppm) for the aphid. However, their resistance to acephate, demeton 5-methyl and pirimicarh varied depending on the clones, among which green-colored clones were generally more resistant to the pesticides than red-colored ones. No association was found between the insecticide resistance and the karyotype of the aphid in this experiment.

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