• 제목/요약/키워드: Collection Methods

검색결과 2,344건 처리시간 0.028초

시료채취 방법에 따른 작업 공정별 Toluene diisocyanates 포집농도 비교 (Comparison of Toluene Diisocyanate Concentrations Collected with Different Sampling Methods by Work Process)

  • 김성호;원종욱;김치년;정우진;노재훈
    • 한국산업보건학회지
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    • 제23권2호
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    • pp.95-102
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    • 2013
  • Objectives: The aim of this study is to present an appropriate sampling method for individual exposure assessment based on a comparison of toluene diisocyanate (TDI) concentrations collected through different sampling methods by work process type. Methods: Two plants handling TDIs in the Incheon area were selected. The samplings were taken during respective processes of spray painting, drying, grinding, and foaming, in which the production of TDIs took on different forms. For the sampling methods for airborne TDIs, open-face cassette holder, modified 2-piece cassette holder, and impinger were used, and the sampling was performed simultaneously at the same locations. Results: The comparison of TDI collection concentrations by each process depending on the sampling method showed high concentrations in the order of the impinger, modified 2-piece cassette holder, and open-face cassette holder for spray painting and foaming. In all processes with the exception of drying, TDI collection concentrations were higher for sampling done with the modified 2-piece cassette holder than with the open-face cassette holder. Conclusions: Based on these results, the modified 2-piece cassette holder was found to be a more appropriate sampling method than the open-face cassette holder when taking individual samples of TDIs from spray painting, grinding, and foaming processes. In particular, for individual exposure assessment of the spray painting process, which features comparatively high collection concentrations compared to the other processes, the use of a modified 2-piece cassette holder is considered appropriate.

Diversity of Yeasts Associated with Natural Environments in Korea

  • Hong, Soon-Gyu;Lee, Kang-Hyun;Bae, Kyung-Sook
    • Journal of Microbiology
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    • 제40권1호
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    • pp.55-62
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    • 2002
  • Biodiversity af yeasts in various natural environments including soils, swamps and plants was investigated. By molecular identification methods based on the partial sequences of 265 rDNA, 69 isolates were assigned to 44 taxa including 27 known species. The remaining 17 taxa could potentially form new species. All of them were classified into Ascomycota, Hymenomycetes, Urediniomycetes and Ustilaginomycetes. Ascomycetous and ustilaginomycetous yeasts were generally isolated from flower samples, and hymenomycetous and urediniomycetous yeasts were generally isolated from soil samples. Distribution of yeast groups exhibited geographical variation. Yeast biodiversity of root sail also varied according to the associated plant species.

화학기상합성에 의해 제조된 $n-TiO_2$ 분말의 분말특성 (Powder Characteristics of $n-TiO_2$ Powder Synthesized by Chemical Vapor Synthesis)

  • 김혜경
    • 한국분말재료학회지
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    • 제6권3호
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    • pp.238-245
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    • 1999
  • The preparation of $n-TiO_2$ powder by the Chemical Vapor Synthesis process (CVS) was studied using the liquid metal organic precursor (TTIP). The residence time and the collection methods were considered as main processing variables through the experiments. The CVS equipment consisted of a micropump and a flashvaporizer, a tube furnace and a tubular collection device. The synthesis was performed at $1000^{\circ}C$ with various sets of collection zone. The residence time and the total system pressure were controlled in the range of 3~20 ms and 10 mbar, respectively. Nitrogen adsorption, X-ray diffraction and electron microscopy were used to determine particle size, specific surface area and crystallographic structure. The grain size of the as-prepared $n-TiO_2$ powder was in the range of 2~8 nm for all synthesis parameters and the powder exhibited only little agglomeration. The relationship between particle characteristics and the processing variables is reviewed based on simple growth model.

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Memory Compaction Scheme with Block-Level Buffer for Large Flash Memory

  • Chung, Weon-Il;Li, Liangbo
    • International Journal of Contents
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    • 제6권4호
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    • pp.22-29
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    • 2010
  • In flash memory, many previous garbage collection methods only merge blocks statically and do not consider the contents of buffer. These schemes may cause more unnecessary block erase operations and page copy operations. However, since flash memory has the limitation of maximum rate and life cycle to delete each block, an efficient garbage collection method to evenly wear out the flash memory region is needed. This paper proposes a memory compaction scheme based on block-level buffer for flash memory. The proposed scheme not only merges the data blocks and the corresponding log block, but also searches for the block-level buffer to find the corresponding buffer blocks. Consequently, unnecessary potential page copying operations and block erasure operations could be reduced, thereby improving the performance of flash memory and prolonging the lifetime of flash memory.

전력계통 운용상태의 신속한 판단을 위한 정보수집 및 추론기법에 관한 연구 (A Study on Information Collection and Inference Technique for Fast Evaluation of Power System Operation State)

  • 박찬엄;홍창호;이승철;문운철
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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    • pp.34-35
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    • 2006
  • This paper presents an information collection and a novel inference technique for evaluation of power system operation state. In most developing countries, power demands are steadily increasing and consequently power systems are becoming larger and more complicated. In addition, power system deregulations further complicate the power system operational tasks, which are resulted in prevailing wide area blackouts worldwide. In this paper, we proposed an effective information collection and operating state evaluation methods using a knowledge-based system. The RTS-79 24 bus system is used as a test system. The power system model is composed with JESS templates and included in the knowledge-base as a part of fixed facts. Dynamic informations are collected from various analysis results and actual operational data. Inferences are performed with rules expressed with terms in different abstraction levels. Future research will be concentrated on intelligent contingency selections for preventing wide area blackouts.

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장시간사용(長時間使用)한 공조용(空調用) 전기집진(電氣集塵)필터의 특성(特性) (Characteristics of long-term operated Electrostatic airclean filter for air-conditioner)

  • 홍영기;강광옥;이성화;손상철
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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    • pp.453-455
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    • 1995
  • In electrostatic airclean filter, the collection efficiency defends on particle charge in the ionizer section. The effect of electrostatic airclean filter condition (deposition of dust, variation of corona discharge current) on corona discharge characteristics was well studied. However, it seems not to be studied on corona discharge characteristics of electrostatic airclean filter respect to contaminated electrode which is caused by practical use. In this paper, Long-term(60days) effects are studied experimentally by two methods. The one is ozone concentration, the other is collection efficiency. Generation of ozone level was increased but collection efficiency was slightly reduced in long-term used electrostatic airclean filter.

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구조개편에 대비한 자료 수집.관리 및 평가 체계의 제안 -지역간 융통전력 산정기법을 중심으로- (A suggestion of data collection, administration and evaluation system for deregulation environment)

  • 황성욱;김정훈;김준환;김성구;방민재;원종률
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 A
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    • pp.389-391
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    • 2001
  • The existing data systems and structures scope primarily the data evaluation which is performed by only corresponding or Interesting bodies. And the bodies i.e. electricity and energy utilities' quarters don't exchange the data each other because methods, purposes, etc. of the collection are different. This paper presents a new integrated system of data collection, administration and evaluation on the power system. And the system is applied to PSS/E data structures.

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북경대학 소장 한대의간(漢代醫簡)과 노관산 의간(老官山醫簡)의 비교 연구 (A Study Comparing the Han Period Bamboo Slats of the Beijing University Collection with the Laoguanshan Collection)

  • 김범수;김기왕
    • 대한한의학원전학회지
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    • 제36권1호
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    • pp.33-43
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    • 2023
  • Objectives : Overlapping contents between two recently discovered Han period bamboo slats, the so-called "Beidahanjian" and the "Liushibingfang" have been identified. This study aims to present new knowledge that could be inferred from the concordance of these two texts. Methods : The most recent original texts of the medical part of the Beidahanjian and medical texts excavated from the Laoguanshan in addition to the Liushibingfang were compared with each other to determine identical parts. The meaning of these concordances was explored. Results : Identical sentences in two verses in the Beidahanjian and the Laoguanshan were identified. Conclusions : The Beidahanjian is a credible Western Han period text, of which the medical bamboo slats are likely to comprise an independent text that is a combination of ancient folk prescriptions and those of doctors.

OASIS의 선정지침 개선(안)에 관한 연구 (A Study on Improving the OASIS Selection Guidelines)

  • 노영희;고영선
    • 한국비블리아학회지
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    • 제23권3호
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    • pp.105-137
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    • 2012
  • 웹상에서 유통되는 정보자원의 역사적, 사회적, 문화적 가치는 전 세계적으로 인정받고 있으며, 인류 유산으로 후세에게 물려주기 위한 웹 아카이빙 사업이 수행되고 있다. 이 사업에서 가장 기본이 되는 것은 수많은 웹 자원 중 수집 및 보존의 가치가 있는 웹 자원을 선정하기 위한 선정지침이라 할 수 있다. 본 연구에서는 선행연구 및 국내외 웹 아카이빙 선정지침을 집중적으로 분석하여 OASIS를 위한 선정지침의 개선안을 제안하였다. 첫째, 웹 자료에 대한 정의, 용어정의, 수집기본원칙, 수집방법, 수집주기, 구체적인 아카이빙 대상자원 선정에 대해서 개선 내용을 제안하였다. 둘째, 수집대상자료에 대해서 대폭적으로 개선 내용을 제안하였으며, 웹 아카이빙 선정제외자료에 대한 제안도 하였다. 마지막으로, 수집방법과 온라인 자료 납본과의 관련성, 선정대상자료에 대한 목록데이터베이스 구축의 필요성, 협력형 아카이빙 정책의 필요성에 대해서 논의하였다.

다중 가상 검지선을 이용한 실시간 교통정보 수집 (Real-Time Traffic Information Collection Using Multiple Virtual Detection Lines)

  • 김의철;김수형;이귀상;양형정
    • 정보처리학회논문지B
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    • 제15B권6호
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    • pp.543-552
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    • 2008
  • ATIS(Advanced Traveler Information System)는 교통 상황이나 주행 정보 등을 실시간으로 제공하여 이용자의 편익을 도모하는 시스템이다. ATIS를 위해 영상 이미지를 분석하여 교통정보를 수집 수집하는 방식은 크게 영역에 루프 검지기를 설정하여 측정하는 방식과, 영상 분석을 통해 차량을 검출하고 추적하는 방식으로 나뉜다. 본 연구에서는 차선마다 가상 검지기를 설치하는 방식을 기초로, 영상 분석 방법의 차량 위치 추적 방식을 응용하여 교통정보를 측정하는 시스템을 제안한다. 이때 가상 검지기 방식의 단점을 보완하기 위해 차선마다 다중의 가상 검지선을 설정하여, 검지 영역 내에 여러 대의 차량이 진입하거나 차량의 차선 변경 시에도 효과적으로 교통정보를 추출할 수 있게 하였고, 영상분석 방식의 문제점인 검지영역의 크기 증가에 따른 차량 추출 시간의 증가를 해결하기 위해 검지 영역 내에서 대표 픽셀을 추출하여 교통정보를 측정하였다. CCTV를 이용하여 취득한 영상에 제안하는 시스템을 이용하여 차량의 평균 속도와 차선별 교통량 측정한 결과 실제 교통량대비 평균 92.32%의 차량 검지율를 보였다.