• 제목/요약/키워드: Collection time

검색결과 2,310건 처리시간 0.024초

2단 평행판 정전식 집진기에서의 입자하전 및 포집 (Particle Charging and Collection in Two-Stage, Parallel-Plate Electrostatic Precipitators)

  • 오명도;유경훈;이준식
    • 대한기계학회논문집
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    • 제18권2호
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    • pp.432-445
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    • 1994
  • From a theoretical analysis point of view, the 2-stage precipitator is decomposed into two units: charging cell and collecting cell. Collection efficiency predictions of the two-stage parallel-plate electrostatic precipitator have been performed theoretically incorporating with the charging and the collecting cells. Particle trajectorise passing the charging cell have been modeled as a simple one. Particle charge distribution at the outlet of the charging cell is calculated through integration of the present unipolar combined charging rate along the entire particle trajectory, and average charge of particles at the outlet of the charging cell is obtained from the particle charge distribution. As for the collecting cell, the diminution of particle concentration along the longitudinal direction of the collecting cell is investigated considering the conventional Deutsch's theory and the laminar theory. One should note that the collection efficiency formula derived is based on monodisperse aerosols. It has been confirmed through the analysis that predictions of particle charge by applying White's unipolar diffusion charging theory overpredict actual cases in the continuum regime, while predictions by Fuch's unipolar diffusion charging theory indicate the reasonable result in the same regime. Theoretical predictions of collection efficiency are also compared with the available experimental results. Comparisons show that the experimental results are consistently located in the collection efficiency region bounded by the two limits, the Deutsch and the laminar collection efficiencies. Finally design parameters of the 2-stage electrostatic precipitator have been investigated systematically through the one-variable-at-a-time method in terms of collection efficiency. Applied voltages on the corona wire of the charging cell and the plate of the collecting cell, and the average air velocity have been selected as the design parameters.

현대 남성복 컬렉션에 나타난 키치(Kitsch) 특성 (Kitsch Features Expressed in Contemporary Men's Collection)

  • 유현서;윤정아;이연희
    • 한국의상디자인학회지
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    • 제17권2호
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    • pp.11-25
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    • 2015
  • This study analyzed features in contemporary men's collection to provide data for characteristics of kitsch in men's collection. The research method was to see background of the concept of kitsch through the domestic and international publications, the Internet, paper. Five designers' collections that have characteristics of kitsch were selected. The range of collection is from the 2000 S/S to 2011 F/W in Men's collection. The results are as follows: kitsch characteristics could be classified by amusements, inappropriateness, satire. First, exaggerative amusements in men's collection appeared exaggerated form, large size, which is ridiculous at the same time. Infantile amusements represents the image of a pure concentric matching accessories such as toys to the children express. sensual amusements reveals the sexual instincts and desires and people can feel satisfaction through sensual amusements. Second, inappropriateness is characteristic of kitsch to escape from normal life. Clothing does not fit the body and destroyed the design or design of this feature appears. It looks clumsy and strange. Inappropriateness characteristic in men's collection can be divided into inadequate performance and sexual inappropriateness. Third, satire can be divided into resistant satire, imitative satire, and popular satire. Resistance satire with anti-social tendencies through their clothing is achieved by expressing their needs. It was affected by sub-culture like Hippie or Punk. Imitative satire is to imitate other culture, customs and race. It is to resolve complaints through the consumption of things in disparities of wealth and materialism in the society. Popular satire is to express emotions that are free using materials that can recycling like can, bottle or paper.

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명세 기반 인공지능 학습 데이터 수집 방법 (A Specification-Based Methodology for Data Collection in Artificial Intelligence System)

  • 김동기;최병기;이재호
    • 정보처리학회논문지:소프트웨어 및 데이터공학
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    • 제11권11호
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    • pp.479-488
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    • 2022
  • 최근 기계학습 기술이 빠르게 발전함에 따라 지능형 시스템을 구성하는 여러 기술 중에서 인지, 추론 및 판단, 행위와 같은 분야에서 기계학습을 활용한 연구가 활발히 이루어지고 있다. 이러한 기계학습을 활용하기 위해서는 학습을 위한 데이터의 구축이 필수적이다. 하지만 데이터가 생성되는 환경에 따라 생성되는 데이터의 종류가 다양하고, 기계학습에 활용할 학습모델에 따라 요구되는 데이터의 종류와 양식이 다르다. 이로 인해 새로운 환경에서 기존의 데이터 수집 방법을 재사용하지 못하고 매번 특화된 데이터 수집 모듈을 개발해야 한다는 문제가 있다. 본 논문에서는 위와 같은 문제를 해결하기 위해 명세 기반 인공지능 데이터 수집 방법을 제안하여 데이터 수집 환경에 따른 데이터 수집 방법의 재사용성을 확보하고, 데이터 수집 기능 구현을 자동화할 수 있는 방법을 제시하고자 한다.

활성탄집진시설의 시간변화에 따른 총탄화수소의 집진효율성 및 경제성에 관한 연구 (A Study on Collection Efficiency And Economy of Total Hydrocarbons in Accordance with Time Changes at Activated Carbon Collection Facility)

  • 김성중;한대희;우인성
    • 대한안전경영과학회지
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    • 제16권2호
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    • pp.231-236
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    • 2014
  • In this study, the changes in collection efficiencies due to the time changes of activated carbons were ascertained, and in order to identify the magnitude of adsorption, the before-use and after-use iodine adsorption values were analyzed. In addition, as a result of examining the characteristics of continuous process and non-continuous process and as a result of investigating whether the emission standards would be maintained, the continuous process and printing facilities were seen as not being able to maintain the emission standards. Also were found, in the case of non-continuous process,-taking into consideration the special nature of the job -for 4${\o}$ palletized charcoal, a collection efficiency near 50% was shown even after 96 hours. Also, when the inlet concentration was about 300ppm, it is thought that the emission standards would be maintained if the activated carbons are replaced within at least 96 hours in the case of 4${\o}$ palletized charcoal and the use was deemed pointless in the case of carbon. The results of this study are expected to provide assistance in selecting replacement periods for activated carbons and in selecting absorbents at the project sites, and are expected to be of significant help in the selection of precipitators that can collect total hydrocarbons for compliance of the emission standards.

A Study on the Improvement of VDS Data Collection Algorithm Using Kalman Filter

  • Choi, NakJin;Kim, SungJin;Ju, YongWan;Suh, SangMin;Choi, JaeHong;Lee, JunDong
    • 한국컴퓨터정보학회논문지
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    • 제26권9호
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    • pp.133-141
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    • 2021
  • 도로 이용자의 교통정보에 대한 수요 증가와 효율적인 도로 이용을 위해 또한, 지능형 교통체계(ITS, Intelligent Transport Systems)의 기본 기술로 교통정보를 수집하여 제공하는 시스템에 대한 개발과 요구가 지속되고 있다. 고속도로에서 가장 많이 사용하는 교통정보 수집 도구로는 차량검지기(VDS)와 단거리무선통신(DSRC)이 있으며, 신뢰성 있는 교통정보의 생성을 위해서는 질 높은 교통데이터 수집 및 가공 기술과 더불어 수집된 자료의 효율적 관리 및 활용이 필요하다. 본 연구에서는 교통정보 수집·제공 기술의 현황을 기술하고, VDS를 통하여 수집되는 교통정보의 현황과 문제점에 대하여 분석한다. 이를 바탕으로 VDS 데이터의 차량정보 계측에 칼만 필터를 활용하여 개선된 수집 알고리즘을 제시하고자 한다. 본 연구의 알고리즘을 활용하면 계측 시 필연적으로 발생하는 노이즈 제거 뿐만 아니라 추정 값의 시간지연(time delay)을 최소로 할 수 있다.

Age of Data in Contemporary Research Articles Published in Representative General Radiology Journals

  • Kang, Ji Hun;Kim, Dong Hwan;Park, Seong Ho;Baek, Jung Hwan
    • Korean Journal of Radiology
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    • 제19권6호
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    • pp.1172-1178
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    • 2018
  • Objective: To analyze and compare the age of data in contemporary research articles published in representative general radiology journals. Materials and Methods: We searched for articles reporting original research studies analyzing patient data that were published in the print issues of the Korean Journal of Radiology (KJR), European Radiology (ER), and Radiology in 2017. Eligible articles were reviewed to extract data collection period (time from first patient recruitment to last patient follow-up) and age of data (time between data collection end and publication). The journals were compared in terms of the proportion of articles reporting the data collection period to the level of calendar month and regarding the age of data. Results: There were 50, 492, and 254 eligible articles in KJR, ER, and Radiology, respectively. Of these, 44 (88%; 95% confidence interval [CI]: 75.8-94.8%), 359 (73%; 95% CI: 68.9-76.7%), and 211 (83.1%; 95% CI: 78-87.2%) articles, respectively, provided enough details of data collection period, revealing a significant difference between ER and Radiology (p = 0.002). The age of data was significantly greater in KJR (median age: 826 days; range: 299-2843 days) than in ER (median age: 570 days; range: 56-4742 days; p < 0.001) and Radiology (median age: 618; range: 75-4271 days; p < 0.001). Conclusion: Korean Journal of Radiology did not fall behind ER or Radiology in reporting of data collection period, but showed a significantly greater age of data than ER and Radiology, suggesting that KJR should take measures to improve the timeliness of its data.

일반국도 교통량조사의 조사 유형별 개선 방안 (A Study on Improving the National Highway Traffic Counts System : With Focus on Short Duration Counts and Continuous Counts)

  • 이상협;하정아;윤태관
    • 대한토목학회논문집
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    • 제32권3D호
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    • pp.205-212
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    • 2012
  • 일반국도 교통량조사는 크게 수시조사와 상시조사로 나누어진다. 수시조사는 상시조사와 달리 표본조사로 시행되고 있으며 조사 시기에 따라 AADT에 대한 오차의 크기가 달라진다. 따라서 본 연구에서는 수시조사의 AADT 추정의 정확도를 높이기 위하여 도로 유형별로 AADT와의 오차가 작은 수시조사 시기를 파악하고자 하였다. 그리고 상시조사는 조사 지점에 설치되어 있는 장비의 고장이나 오작동 등으로 인하여 교통량 자료가 정상적으로 수집되지 않아 해당 지점의 교통량 변동을 제대로 파악할 수 없는 경우가 자주 발생한다. 따라서 본 연구에서는 장비 설치년도, 중차량 비율 등이 장비의 고장이나 오작동의 원인이 될 수 있는 지를 장비 유지보수 횟수와의 상관관계 분석을 통하여 파악하고자 하였다.

유치원 4세반에서 간식과 점심시간의 교육적 의미 재조명 (Reinterpretation of Educational Meanings of Snack and Lunch Time in a Kindergarten Class of 4-Year-Old Children)

  • 원유옥;김송이
    • 한국생활과학회지
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    • 제22권6호
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    • pp.571-586
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    • 2013
  • The purpose of this study was to examine educational meanings of snack and lunch time of 4-year-old children and their teachers in a kindergarten class. The study was done in the Class of 4-year-old children in S Kindergarten located in Songpa-gu, Seoul. And 30 children of this class, Teacher A who is the teacher in charge of the Class, and Teacher B who is the researcher and teacher in charge of it participated in it. The study was carried out by the ethnography method and data collection was done through participation observation, interviews, video and voice recording, and data collection of photography shooting. The results are as follow: First, the children had private conversations, shared their cultures, deepened and expanded their existing concepts, expressed their emotions and relieved their tension, and strengthened relations with friends during the snack and lunch time. Second, the teachers promoted conversation and communication, gave the opportunity that the children can set the lunch table by themselves and tried to make the snack and lunch time with the children by discussing what they are how they are operated with them together. In conclusion, the snack and lunch time can be more meaningful time for children when there are proper educational plans and support of teachers which are considered children's viewpoints.

Direct Embryo Collection(DEC)에 의한 한우의 수정란 채란 (Embryo Recovery by Direct Embryo Collection (DEC) in Korean Native Cattle (Hanwoo))

  • 유한준;이용승;박정준;김기원;박춘근
    • 한국수정란이식학회지
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    • 제26권3호
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    • pp.153-158
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    • 2011
  • This study was performed in order to simplify the operation and minimize stress of donor and be readily available in the field with low cost and high quality embryos using the Direct Embryo Collection (DEC). Donors, at random stages of the estrous cycle, received a CIDR. 7 days later, 200 mg FSH was treated with 40, 30, 20, 10 mg FSH levels in declining doses twice daily by intramuscular injection for 4 days. On the 3rd day administration of FSH, 25 mg $PGF_2{\alpha}$ was administered and CIDR was withdrawn. After FSH injections were complete, donors were artificially inseminated twice at 12 hr intervals. The donor cattle received 250 ${\mu}g$ GnRH at time of 1 st insemination and embryos were recovered 8 days after the 1st insemination. Embryo collection from superovulated donors was performed to flushing by non-surgical methods of 3-way, 2-way and DEC (l-way). The average number of recovered embryos were 11.25${\pm}$0.63, 12.5${\pm}$0.65 and 11.75${\pm}$0.48 from operations of 3-way, 2-way and DEC methods, respectively. There were no significant differences among the embryo collection methods. Also, The average number of transferable embryos were 6.25${\pm}$0.48, 7.25${\pm}$0.48 and 7.25${\pm}$0.63 from each embryo collection procedures. The number of transferable embryos was no differences among the 3-way, 2-way and DEC methods, respectively. Meanwhile, the ratio of transferable embryos for all recovered embryos from DEC methods was higher as 61.7 % than 55.6 %, 58 % from methods of 3-way, 2-way. And the flushing solution required for recovering embryos by DEC method was significantly lower as 0.28${\pm}$0.32 1 than 1.8${\pm}$0.12 1, 1.75${\pm}$0.10 1 from 3-way, 2-way methods (p<0.05). Also, the time required for recovering embryos by DEC methods was significantly lower as 27${\pm}$2 min than 51${\pm}$3, 45${\pm}$2 min, respectively (p<0.05). In conclusion, these results suggest that DEC method for embryo collection may be effectively used for production of in vivo embryos using less flushing solution and, it might be effectively available in the field compared to conventional embryo recovery methods using 3-way or 2-way balloon catheter.

Garbage Collection Technique for Balanced Wear-out and Durability Enhancement with Solid State Drive on Storage Systems

  • Kim, Sungho;Kwak, Jong Wook
    • 한국컴퓨터정보학회논문지
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    • 제22권4호
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    • pp.25-32
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    • 2017
  • Recently, the use of NAND flash memory is being increased as a secondary device to displace conventional magnetic disk. NAND flash memory, as one among non-volatile memories, has many advantages such as low power, high reliability, low access latency, and so on. However, NAND flash memory has disadvantages such as erase-before-write, unbalanced operation speed, and limited P/E cycles, unlike conventional magnetic disk. To solve these problems, NAND flash memory mainly adopted FTL (Flash Translation Layer). In particular, garbage collection technique in FTL tried to improve the system lifetime. However, previous garbage collection techniques have a sensitive property of the system lifetime according to write pattern. To solve this problem, we propose BSGC (Balanced Selection-based Garbage Collection) technique. BSGC efficiently selects a victim block using all intervals from the past information to the current information. In this work, SFL (Search First linked List), as the proposed block allocation policy, prolongs the system lifetime additionally. In our experiments, SFL and BSGC prolonged the system lifetime about 12.85% on average and reduced page migrations about 22.12% on average. Moreover, SFL and BSGC reduced the average response time of 16.88% on average.