• 제목/요약/키워드: Collection 5

검색결과 3,355건 처리시간 0.031초

대기 에어로졸 측정용 3단 임팩터의 설계 및 성능평가 (Design and Performance Evaluation of a Three Stage Impactor)

  • 지준호;배귀남;황정호
    • 한국대기환경학회지
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    • 제17권6호
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    • pp.441-450
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    • 2001
  • A three stage impactor with the cutoff diameters of 1, 2.5, and 10$\mu\textrm{m}$ in aerodynamic diameter was developed and tested. The gravimetric method and the particle counting method were utilized to evaluate the collection performance of each stage. A vibrating orifice aerosol generator was employed to generate monodisperse test aerosols larger that 2$\mu\textrm{m}$ in diameter. Polystyrene latex (PSL) particles smaller than 2$\mu\textrm{m}$ in diameter were generated by an atomizer and the particle number concentration was measured by an Aerodynamic Particle Sizer Spectrometer. The experimental cutoff diameters obtained from the particle collection efficiency curves are in good agreement with the designed values. The square roots of Stokes number at 50% collection efficiency for stage 1, 2, and 3 are 0.42, 0.48, and 0.45, respectively. Effects of the particle bounce and the impaction plate on the collection efficiency were investigated. The collection efficiency curves including effect of the particle bounce were also compared with those of the MOUDI cascade impactor.

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비비안 탐 컬렉션에 나타난 중국풍 디자인 특성 연구 (A study on Characteristics of Chinese Style Reflected in the Vivienne Tam Collection)

  • 강란영;박주희
    • 한국의류산업학회지
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    • 제21권5호
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    • pp.527-539
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    • 2019
  • This study examined the Chinese style in the Vivienne Tam collection as well as explored diversity and modern interpretation of a Chinese style used in modern fashion. The study also investigated the concept and history of the Chinese style as well as analyzed the Chinese style in the collection based on a consideration of a Chinese element that is the basic structure with an understanding of Vivienne Tam and general collection themes. As a result of research, the Chinese style appeared in the Vivienne Tam collection was comprehensive with 43 Chinese elements including Animals, Flower & Grass among the Nature elements, Mythology Religion among the Figure elements, Historical Artifacts, Clothing, Oral Literature, Entertainment, Fine Arts. Technique, Folk holiday among Culture elements and Philosophy among Spirit elements, which accounted for 57.6% of the collection. The formative characteristics that included Chinese elements were extended, abstracted, distorted or transformed; in addition, some abstract elements were embodied into animals, images and certain particular forms to present a theme. In addition to two-dimensional method to print Chinese elements on fabric, they were also expressed as a three-dimensional texture or a silhouette, achieving clear and bold harmony. The aesthetic characteristic is a mixture of Eastern and Western way of thinking. Her costume has a political and historical meaning beyond the imitation of elements that represent the development of a pleasant and interesting design.

충진층식 세정집진기의 집진특성 실험 (An Experiment on the Particle Collection Characteristics in a Packed Wet Scrubber)

  • 유경훈;노희환;최은수;김종균
    • 설비공학논문집
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    • 제15권4호
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    • pp.305-311
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    • 2003
  • DOP aerosol particles with geometric mean diameter of 0.5-3.0 ${\mu}{\textrm}{m}$, geometric standard deviation of 1.1-1.3 and total number concentration of 1,500-8,000 Particles/㎤ were used to determine collection efficiencies of a packed wet scrubber with respect to particle size. The tested operating variables included air velocity and water injection rate. It was shown from the experimental results that the collection efficiencies increased with increasing water injection rate and decreasing air velocity. Meanwhile, as for the particle size variation, all of the collection efficiency curves increased rapidly between 0.57-1.41${\mu}{\textrm}{m}$ for the range of water injection rate above 30 L/min. It was also seen that the collection efficiency of a packed wet scrubber is mainly governed by the mechanism of inertial impaction.

Digital Collection and Development Initiatives in Engineering College Libraries: An Analytical Survey

  • Kumar, K.
    • International Journal of Knowledge Content Development & Technology
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    • 제4권1호
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    • pp.5-21
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    • 2014
  • The purpose of this paper is to study the initiatives on digital collection and development in engineering college libraries in the Rayalaseema Region of Andhra Pradesh. Eighty-one engineering college libraries in Rayalaseema Region have been surveyed to assess the initiatives taken on digital collection and development. This paper highlights opinions of librarians on most preferred digital materials and various digital resources acquainted with their library. The digital library initiatives cover a variety of activities starting from the digital collection building, digitization, digital collection, maintenance, and digital preservation. It is found that 34.57% of libraries are in the process of building digital collections, which is an encouraging trend among Engineering Educational Institutions in Rayalaseema Region.

Building a text collection for Urdu information retrieval

  • Rasheed, Imran;Banka, Haider;Khan, Hamaid M.
    • ETRI Journal
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    • 제43권5호
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    • pp.856-868
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    • 2021
  • Urdu is a widely spoken language in the Indian subcontinent with over 300 million speakers worldwide. However, linguistic advancements in Urdu are rare compared to those in other European and Asian languages. Therefore, by following Text Retrieval Conference standards, we attempted to construct an extensive text collection of 85 304 documents from diverse categories covering over 52 topics with relevance judgment sets at 100 pool depth. We also present several applications to demonstrate the effectiveness of our collection. Although this collection is primarily intended for text retrieval, it can also be used for named entity recognition, text summarization, and other linguistic applications with suitable modifications. Ours is the most extensive existing collection for the Urdu language, and it will be freely available for future research and academic education.

한국농업미생물자원센터 (KACC)에 보존중인 Colletotrichum gloeosporioides와 C. acutatum의 재동정 (Reidentification of Colletotrichum gloeosporioides and C. acutatum Isolates Stored in Korean Agricultural Culture Collection (KACC))

  • 김대호;전영아;고승주;이종규;홍승범
    • 식물병연구
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    • 제12권3호
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    • pp.168-177
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    • 2006
  • 한국농업미생물자원센터(Korean Agricultural Culture Collection, KACC)에 보존되어 있는 Colletotrichum gloeosporioides 39 균주와 C. acutatum 5 균주를 ribosomal DNA-ITS와 $\beta$-tubulin 부분염기서열과 PDA와 Benomyl-PDA배지에서의 생장 특성에 의하여 재동정 하였다. 그 결과 13 균주가 Talhinhas 등의 C. acutatum A2 그룹으로, 5 균주가 C. acutatum A3 그룹으로, 1 균주가 C. acutatum A4 그룹으로, 18 균주가 Moriwaki 등의 C. gloeosporioides ribosomal DNA group(RG) 4로 2 균주가 C. gioeosporioides RG6로 2 균주가 c. boninense RG5로 2 균주는 C. coccodes RG2 그리고 1 균주는 c. dematium RG12로 재동정되었다. 이들 중에서 한국에서 분리된 31 균주는 12 균주가 C. acutatum A2 그룹으로, 1 균주가 C. acutatum A3 그룹으로, 14 균주가 C. gloeosporioides RG4 로 2 균주가 C. gloeosporioides RG6로 1 균주가 C. boninense RG5로 그리고 1 균주는 C. dematium RG12로 동정되었다. 더불어 C. acutatum/C. gloeosporioides의 분류적인 특징과 국내 주요 기주별 분포 등에 대하여 고찰하였다.

Effects of Spray Surfactant and Particle Charge on Respirable Coal Dust Capture

  • Tessum, Mei W.;Raynor, Peter C.
    • Safety and Health at Work
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    • 제8권3호
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    • pp.296-305
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    • 2017
  • Background: Surfactant-containing water sprays are commonly used in coal mines to collect dust. This study investigates the dust collection performance of different surfactant types for a range of coal dust particle sizes and charges. Methods: Bituminous coal dust aerosol was generated in a wind tunnel. The charge of the aerosol was either left unaltered, charge-neutralized with a neutralizer, or positively- or negatively-charged using a diffusion charger after the particles were neutralized. An anionic, cationic, or nonionic surfactant spray or a plain water spray was used to remove the particles from the air flow. Some particles were captured while passing through spray section, whereas remaining particles were charge-separated using an electrostatic classifier. Particle size and concentration of the charge-separated particles were measured using an aerodynamic particle sizer. Measurements were made with the spray on and off to calculate overall collection efficiencies (integrated across all charge levels) and efficiencies of particles with specific charge levels. Results: The diameter of the tested coal dust aerosol was $0.89{\mu}m{\pm}1.45$ [geometric $mean{\pm}geometric$ standard deviations (SD)]. Respirable particle mass was collected with $75.5{\pm}5.9%$ ($mean{\pm}SD$) efficiency overall. Collection efficiency was correlated with particle size. Surfactant type significantly impacted collection efficiency: charged particle collection by nonionic surfactant sprays was greater than or equal to collection by other sprays, especially for weakly-charged aerosols. Particle charge strength was significantly correlated with collection efficiency. Conclusion: Surfactant type affects charged particle spray collection efficiency. Nonionic surfactant sprays performed well in coal dust capture in many of the tested conditions.

대학도서관 시설기준에 관한 연구 (A study on standards for college and university library building areas)

  • 손정표
    • 한국도서관정보학회지
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    • 제23권
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    • pp.363-404
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    • 1995
  • This study is to set up a model of minimum and optimum standards for college and university library building areas in Korea. The results of this study are summarized as follows: 1. minimum standards(proposal) At first, Areas needed by factors of space component are as follows: User space --- 0.45 $m^{2}$ per student. Collection space --- 0.0107 $m^{2}$ per volume Staff space --- 10.1 $m^{2}$ per person Space attached to user, collection and staff space --- 5% of the sum of user, collection and staff areas(0.041 $m^{2}$ per student). Nonassignable space --- 25% of the sum of user, collection and staff areas (0.21 $m^{2}$ per student). Next, the formula to calculate the total area of the college and university library building is as follows: N = 0.45T $m^{2}$(a) + 0.0107V $m^{2}$(b) + 10.1S $m^{2}$(c) + 0.05(a+b+c) $m^{2}$, NS = 0.25N $m^{2}$. 2. Optimum standards(proposal) At first, Areas needed by factors of space component are as follows: User spae --- 0.64 $m^{2}$) per student. Collection space --- 0.01 $m^{2}$ per volume Staff space --- 9.7 $m^{2}$ per person Space attached to user, collection and staff space --- 5% of the sum of user, collection and staff areas(0.073 $m^{2}$ per student). Nonassignable space --- 25% of the sum of user, collection and staff areas(0.38 $m^{2}$ per student). Next, the formula to calculate the total area of the college and university library building is as follows: N = 0.64T $m^{2}$(a) + 0.01V $m^{2}$(b) + 9.7S $m^{2}$(c) + 0.05(a+b+c) $m^{2}$, NS = 0.25N $m^{2}$.

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능동형 RFID 시스템의 성능 향상을 위한 연구 (Study on the Performance Improvement of Active RFID System)

  • 김지태;김진성;이강원
    • 한국통신학회논문지
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    • 제40권5호
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    • pp.871-885
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    • 2015
  • 본 연구에서는 우선 고속으로 태그 수집을 위한 2.4 GHz 능동형 RFID 시스템의 시뮬레이션 모델을 구축 하였다. 그리고 단순화 된 Collection 명령과 Ack 절차, 슬롯의 충돌 확률(k1)과 충돌이 발생한 슬롯의 평균 태그 수($k_2$)를 이용하여 태그수를 예측하는 새로운 방법을 제안하였다. 이들에 따른 능동형 RFID 시스템의 성능 추적을 구축한 시뮬레이션 모델을 통해 획득하였다. Query 명령을 사용하여 Collection 명령과 Ack를 간소화하고 $k_1$$k_2$를 이용하여 태그수를 예측하는 방법의 조합이 모든 성능 면에서 가장 우수한 것으로 나타났다. 이는 Query 명령을 이용한 Collection 명령과 Ack의 간소화는 태그 인식 속도를 줄이는데 기여했고 $k_1$$k_2$를 이용하여 태그수를 예측하는 방법은 Throughput을 향상시킬 뿐만 아니라 이로 인해 Collection 라운드 횟수를 줄여 태그 인식 속도를 줄일 수 있었다. 본 연구에서 제안한 방법은 Throughput, 평균 인식 시간, 1초 안의 평균 인식률 모두에서 이상적인 경우의 성능값과 매우 유사하게 나타나 제안한 방법의 유효성을 확인 할 수 있었다.

수거체계 및 재활용 인식조사를 통한 기저귀 수거방안 연구 (Research on Collection Method of Used Diaper Based on Foreign Collection Method and Perception Survey)

  • 김경신
    • 자원리싸이클링
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    • 제26권5호
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    • pp.29-38
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    • 2017
  • 본 연구는 기저귀 재활용을 정책적으로 도입 시 최적의 수거방안을 마련하고자 해외 사례조사를 통해 국내 실정에 맞는 적절한 방안을 제안하고, 실제 수거에서 발생할 수 있는 문제점을 파악하고자 시민들 대상으로 인식조사를 실시하여 사회적 수용도를 높일 수 있는 방안에 대해 조사하였다. 조사 결과 시민들은 경제적 부담 및 위생문제 해결을 위한 방안 마련이 중요하다고 인식하고 있었고, 주거지 근처 전용 수거함에 전용봉투를 통한 주 2회 수거 빈도가 적절하다고 응답하였다. 현행 폐기물관리법 상 재활용 대상이 되는 생활폐기물의 경우 지자체 단위로 업체와 개별 계약을 통해 수거되고 있기 때문에 사용 후 기저귀 역시 현행 방식과 동일하게 지자체 수거 위탁 시스템을 활용하여 자원회수시설에서 최종 처리하는 방안이 적절할 것으로 보인다. 이러한 관점에서 지자체 연계를 통한 시범사업을 가정하고 최적의 지자체를 선정하는 방안을 위해 여러 대안을 제시하였다. 향후 기저귀 재활용을 전 사회적으로 도입할 때 본 연구 조사결과를 통해 도출된 수거방식을 고려하여 인구밀집 지역을 대상으로 시범사업을 기획, 설계하여 운영한다면 보다 경제성이 확보된 결과를 도출할 수 있을 것으로 보인다.