• 제목/요약/키워드: Rate of Use

검색결과 10,420건 처리시간 0.043초

대형디젤엔진의 오염물질 배출특성 (Characteristics of Exhaust Emissions from a Heavy-duty Diesel Engine)

  • 엄명도;류정호;이종태;임철수
    • 한국자동차공학회논문집
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    • 제7권9호
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    • pp.20-27
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    • 1999
  • The proportion of diesel vehicle is very high in this country . PM and NOx emitted from diesel-posered vehicle is severely ;affecting to be air quality . Especially, diesel particulate matters(DPM) including black smoke are hazardous air pollutants to human health and environment. In order to reduce the exhaust emissions from diesel engines, it is necessary to analyze the characteristics of exhaust emissions from diesel engines in various driving conditions. Recently, there are occasion to increase the fuel consumption rate to engine power up. So, in this study we have tested a diesel engine detached from in use -diesel vehicle and analyzed exhaust emission by driving condition and fuel dispersion rate. From this results, we will prepare the comprehensive management plan for exhaust emissions from diesel vehicles and contribute to the improvement of air pollution in urban area.

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Physics analysis of new TRU recycling options using FCM and MOX fueled PWR assemblies

  • Cho, Ye Seul;Hong, Ser Gi
    • Nuclear Engineering and Technology
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    • 제52권4호
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    • pp.689-699
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    • 2020
  • In this work, new multi-recycling options of TRU nuclides using PWR fuel assemblies comprised of MOX and FCM (Fully Ceramic Micro Encapsulated) fuels are suggested and neutronically analyzed. These options do not use a fully recycling of TRU but a partial recycling where TRUs from MOX fuels are recycled while the ones from FCM fuels are not recycled due to their high consumption rate resulted from high burnup. In particular, additional external TRU feed in MOX fuels for each cycle was considered to significantly increase the TRU consumption rate and the finally selected option is to use external TRU and enriched uranium feed as a makeup for the heavy metal consumption in MOX fuels. This hybrid external feeding of TRU and enriched uranium in MOX fuel was shown to be very effective in significantly increasing TRU consumption rate, maintaining long cycle length, and achieving negative void reactivity worth during recycling.

도시화에 따른 갑천유역의 지하 수문 특성 변화 분석

  • 김정곤;손경호;고익환
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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    • pp.64-67
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    • 2006
  • The main purpose of this research was to investigate the effects of urbanization on the groundwater system in the Gap river basin, a sub-basin of the Geum river basin. In this analysis, we constructed a water cycle analysis system using SWAT. Then, changes in soil moisture and recharge rate due to land-use changes were investigated using different land-use data estimated in 1975 and 2000. Simulation results were analyzed for both draught (2001) and flood (2003) years to take into account different hydrologic conditions. It was shown that recharge rate in the most urbanized area (31% change) was reduced by 17% for both periods due to urbanization. The results also indicated that soil moisture decrease due to urbanization was more sensitive in the drought year (2001) than in the flood year (2003), We expect that the results of this research can contribute to providing useful information for managing urban rivers considering river restoration and flood control.

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멀티 라인 레이저 비전 센서를 이용한 고속 3차원 계측 및 모델링에 관한 연구 (Development of multi-line laser vision sensor and welding application)

  • 성기은;이세헌
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 춘계학술대회 논문집
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    • pp.169-172
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    • 2002
  • A vision sensor measure range data using laser light source. This sensor generally use patterned laser which shaped single line. But this vision sensor cannot satisfy new trend which feeds foster and more precise processing. The sensor's sampling rate increases as reduced image processing time. However, the sampling rate can not over 30fps, because a camera has mechanical sampling limit. If we use multi line laser pattern, we will measure multi range data in one image. In the case of using same sampling rate camera, number of 2D range data profile in one second is directly proportional to laser line's number. For example, the vision sensor using 5 laser lines can sample 150 profiles per second in best condition.

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스트레스함수가 감마분포인 가속수명시험 (Accelerated Life Tests under Gamma Stress Distribution)

  • 원영철
    • 대한안전경영과학회지
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    • 제4권3호
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    • pp.59-66
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    • 2002
  • This paper presents accelerated life tests for Type I censoring data under probabilistic stresses. Probabilistic stress, S, is the random variable for stress influenced by test environments, test equipments, sampling devices and use conditions. The hazard rate, $\theta$ is a random variable of environments and a function of probabilistic stress. In detail, it is assumed that the hazard rate is linear function of the stress, the general stress distribution is a gamma distribution and the life distribution for the given hazard rate, $\theta$is an exponential distribution. Maximum likelihood estimators of model parameters are obtained, and the mean life in use stress condition is estimated. A hypothetical example is given to show its applicability.

효율적인 농지이용계획수립 방향에 관한 연구 (A Study on the Directions of Effective Farmland Use Planning)

  • 임상봉
    • 농촌계획
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    • 제1권2호
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    • pp.77-92
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    • 1995
  • The initiative to determine farmland use has been transferred to local side under the decentralized government system in Korea. New Land Act and Rural Development Act support it. Changes in external and internal environments of Korean agriculture require to diversify farmland use. Lpcal development plan may be implemented when specific farmland use plan is prepared. However, (armland use planning has not been prepared by the local governments yet. This study aims to identify problems encountered in current farmland use and suggest directions of effective and reasonable farmland use planning relevant to local conditions. Questionnaire method was used to prove topographical differences of community land demand, Statistical analyses show that farmers desire to utilize marginal farmland for income increase. Growing grass(42.0%) and cash crops(41.7%) was greatly demanded by them. They were generally eager for developing touristic farm (52.1 % ). By topographical characteristics, the eager was greatest in coastal areas, on the contrary, it was relatively low in mountainous areas. There were more farmers who want to expand their farmland in rice farming(48.4%) or rice-horticulture farming(46.9%) areas. Potential retirer among farmers were most in suburban areas, However, it was expected that there would be the highest retirement rate in rice farming areas because of the high rate of aged farmers. Farmland use planning should be incorporated into food production policies and community people's needs for income increase and life improvement. Agriculture promotion areas must be maintained for scale optimized farming and cash crop farming as much as possible. However, minimum portion for other uses in each village or farming community unit should be adopted. Less favored areas will have to be utilized for both agriculture and non-agriculture uses. Priority can be put into touristic resorts as a non-agriculture use. Furthermore, such areas can be used for sustainable agriculture as well as for residence, industry, animal breeding.

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멀티 라인 레이저 비전 센서를 이용한 고속 용접선 추적 기술 (High speed seam tracking using multi-line laser vision sensor)

  • 성기은;이세헌
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 추계학술대회 논문집
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    • pp.584-587
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    • 2002
  • A vision sensor measure range data using laser light source. This sensor generally use patterned laser which shaped single line. But this vision sensor cannot satisfy new trend which needs laster and more precise processing. The sensor's sampling rate increases as reduced image processing time. However, the sampling rate can not over 30fps, because a camera has mechanical sampling limit. If we use multi line laser pattern, we will measure multi range data in one image. In the case of using same sampling rate camera, number of 2D range data profile in one second is directly proportional to laser line's number. For example, the vision sensor using 5 laser lines can sample 150 profiles per second in best condition.

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정맥주사용 수액의 개방후 시간경과에 따른 오염도에 관한 실험연구 (A Study on the Relationship Between Length of Time and Contamination in Open Intravenous Solutions)

  • 김일원
    • 대한간호학회지
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    • 제16권1호
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    • pp.67-80
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    • 1986
  • The use of intravenous solutions for fluid replacement has become an integral part of patient care, This widespread use of intravenous solutions has increased the risk of contamination that can lead to septicemia and phlebitis. The literature regarding contamination of in use intravenous solutions recommends a standard 24-hour time limit on the use of these fluids. But the desings of these studies did not incorporate a time variable related to contamination. In other studies, however, time was a manipulated variable: but data regarding the onset of contamination were conflicting. Because published reports conflict with regard to a time standard related to the use of intravenous therapy, additional empirical data are needed upon which to base the standards of care regulating use of intravenous therapy. This study investigated rate of contamination in simulated in-use intravenous solutions to obtain data from which to recomend a standard time period for the administration of intravenous solutions. In this study samples were drawn from 60 bottles of 5% D/W solution at predetermined time intervals over 48 hours and samples were inoculated to Thio-glychollate Broth. After 10 days' culturing in that Broth, samples were cultured on blood agar plates for 18∼48 hours to determine the rate of contamination. was found at all time Period, regardless of the presence or absence of nurse's gloving in the preparation of fluids, the location in which the experimentations were performed, the contamination level of surrounding air, or the length of time during which solutions were opened. Data from this study support the use of a 48-hour time period on which to base the standard involved in ready-to-use simple intravenous solutions without additives. In emergency departments and critical care areas where intravenous solutions are prepared in advance, the suggested time standard supported by the data generated from this study is 48 hours, not 24 hour. Data from this study support a 24-hour time standard for changing in-use intravenous solutions when the contamination results from the manipulation of intravenous infusion system by hospital personnel, or from some other exogenous sources during administration. Because contamination that does occur within 48 hours in intravenous solutions must be introduced from some exogenous sources, further empirical studies based on the identification of sources of contamination and factors that affect the rate of contamination, are needed to investigate the currently employed standard of intravenous therapy and to provide the patient with more efficient and safer intravenous thereapy.

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A Method for Caption Segmentation using Minimum Spanning Tree

  • Chun, Byung-Tae;Kim, Kyuheon;Lee, Jae-Yeon
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 ITC-CSCC -2
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    • pp.906-909
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    • 2000
  • Conventional caption extraction methods use the difference between frames or color segmentation methods from the whole image. Because these methods depend heavily on heuristics, we should have a priori knowledge of the captions to be extracted. Also they are difficult to implement. In this paper, we propose a method that uses little heuristics and simplified algorithm. We use topographical features of characters to extract the character points and use KMST(Kruskal minimum spanning tree) to extract the candidate regions for captions. Character regions are determined by testing several conditions and verifying those candidate regions. Experimental results show that the candidate region extraction rate is 100%, and the character region extraction rate is 98.2%. And then we can see the results that caption area in complex images is well extracted.

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The Effects of Training on the Proper Use of Respiratory Rate Measurement Devices for Providing High-Quality Artificial Ventilation

  • Jae-Ran Lim;Sung-Hwan Bang;Hyo-Suk Song;Gyu-Sik Shim;Ho-Jin Park
    • 한국컴퓨터정보학회논문지
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    • 제29권3호
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    • pp.165-171
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    • 2024
  • 본 연구는 2급 응급구조사가 호흡부전 및 호흡정지 환자에게 백-밸브 마스크(BVM) 인공호흡 시 호흡량 측정기를 사용하여 적정량의 호흡량과 및 성공률을 알아보고자 한다. 연구는 2023년 12월 11일부터 12일까지 D 대학교에 재학 중인 2급 응급구조사를 대상으로 20명을 선정하여 10명은 호흡량 측정기를 이용하여 BVM 인공호흡을 교육한 실험군으로, 다른 10명은 호흡량 측정기 없이 BVM 인공호흡을 교육한 대조군으로 선정하여 2분간 인공호흡을 제공하는 실험을 하였다. 연구 결과, 대조군에서는 정확한 호흡량을 제공하지 못하였고(p=.025), 호흡 성공률 역시 실험군에서는 2분간 호흡 성공률이 높았으나 대조군에서는 유의한 차이를 보였으며(p=.001), 주관적 호흡량과 측정된 객관적 호흡량이 대조군에서 유의한 차이를 보였다(p=.010). 따라서 호흡량 측정기를 사용한 교육은 2급 응급구조사가 느끼는 주관적 호흡량을 객관적 호흡량과 일치시키고 호흡 성공률을 높여 호흡부전 및 호흡정지와 심폐소생술 시 심장정지 환자의 생존율을 높이는 데 도움이 될 것이다.