• Title/Summary/Keyword: 외대비요

Search Result 367, Processing Time 0.03 seconds

Validation of Load Calculation Method for Greenhouse Heating Design and Analysis of the Influence of Infiltration Loss and Ground Heat Exchange (온실 난방부하 산정방법의 검증 및 틈새환기와 지중전열의 영향 분석)

  • Shin, Hyun-Ho;Nam, Sang-Woon
    • Horticultural Science & Technology
    • /
    • v.33 no.5
    • /
    • pp.647-657
    • /
    • 2015
  • To investigate a method for calculation of the heating load for environmental designs of horticultural facilities, measurements of total heating load, infiltration rate, and floor heat flux in a large-scale plastic greenhouse were analyzed comparatively with the calculation results. Effects of ground heat exchange and infiltration loss on the greenhouse heating load were examined. The ranges of the indoor and outdoor temperatures were $13.3{\pm}1.2^{\circ}C$ and $-9.4{\sim}+7.2^{\circ}C$ respectively during the experimental period. It was confirmed that the outdoor temperatures were valid in the range of the design temperatures for the greenhouse heating design in Korea. Average infiltration rate of the experimental greenhouse measured by a gas tracer method was $0.245h^{-1}$. Applying a constant ventilation heat transfer coefficient to the covering area of the greenhouse was found to have a methodological problem in the case of various sizes of greenhouses. Thus, it was considered that the method of using the volume and the infiltration rate of greenhouses was reasonable for the infiltration loss. Floor heat flux measured in the center of the greenhouse tended to increase toward negative slightly according to the differences between indoor and outdoor temperature. By contrast, floor heat flux measured at the side of the greenhouse tended to increase greatly into plus according to the temperature differences. Based on the measured results, a new calculation method for ground heat exchange was developed by adopting the concept of heat loss through the perimeter of greenhouses. The developed method coincided closely with the experimental result. Average transmission heat loss was shown to be directly proportional to the differences between indoor and outdoor temperature, but the average overall heat transfer coefficient tended to decrease. Thus, in calculating the transmission heat loss, the overall heat transfer coefficient must be selected based on design conditions. The overall heat transfer coefficient of the experimental greenhouse averaged $2.73W{\cdot}m^{-2}{\cdot}C^{-1}$, which represents a 60% heat savings rate compared with plastic greenhouses with a single covering. The total heating load included, transmission heat loss of 84.7~95.4%, infiltration loss of 4.4~9.5%, and ground heat exchange of -0.2~+6.3%. The transmission heat loss accounted for larger proportions in groups with low differences between indoor and outdoor temperature, whereas infiltration heat loss played the larger role in groups with high temperature differences. Ground heat exchange could either heighten or lessen the heating load, depending on the difference between indoor and outdoor temperature. Therefore, the selection of a reference temperature difference is important. Since infiltration loss takes on greater importance than ground heat exchange, measures for lessening the infiltration loss are required to conserve energy.

Evaluation of Stored Rainwater Quality and Economic Efficiency at Yangdo Elementary Rainwater Harvesting System (양도 초등학교 빗물이용시설의 수질 및 경제성 평가)

  • Kim, Kiyoung;Park, Hyunju;Kim, Tschungil;Han, Mooyoung
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.36 no.5
    • /
    • pp.333-341
    • /
    • 2014
  • To supply substitution water, $2m^3$ of capacity of rainwater harvesting system is designed calculating rainfall, catchment area and LPCD and has a effects to 34.4% of substitution water supply and 237 days of service day. Rainwater of drinking water quality was judged to be suitable except for bacteria problem, however, groundwater is exceeded in nitrate nitrogen, the evaporation residue and also bacteria, which means that the rainwater is suitable for use as water supply. In addition, to consider cost-benefit ratio, economic analysis conducted. The result is that B/C ratio of RWHS (10 years) is 1.70. It means total benefit is bigger than cost. Except to social factor in this study, there are a variety of benefit such as flood or drought prevention, educational effects inspiring water conservation awareness.

Management System of USN-based Collaborative Lighting Energy (USN기반 참여형 조명에너지 관리시스템)

  • Kim, Sam-Taek
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.13 no.4
    • /
    • pp.47-53
    • /
    • 2013
  • Nowadays, Advanced country have devised a plan energy-saving through lighting effectiveness and increasing performance of lighting control system. If it uses the LED as a source of light then conserve electricity by 50%. This paper implement LEMS(Lighting Energy Management System) that applicate and Smart Dimmer and Smart Switch that control the digital LED light, support wired-wireless communication using USN(Ubiquitous Sensor Network). This system of validity and reliability control special purpose lamp including indoor and outdoor lighting and landscape lighting effectively. It minimize the use of indoor and outdoor lighting energy by USN remote integral control function of Digital System Lighting of LED and increase effectiveness of energy and is a collaborative system that can feedback the use of electricity by measurement itself through Web and Switch.

Stereo Matching by Dynamic Programming with Edges Emphasized (에지 정보를 강조한 동적계획법에 의한 스테레오 정합)

  • Joo, Jae-Heum;Oh, Jong-kyu;Seol, Sung-Wook;Lee, Chul-Hun;Nam, Ki-Gon
    • Journal of the Korean Institute of Telematics and Electronics S
    • /
    • v.36S no.10
    • /
    • pp.123-131
    • /
    • 1999
  • In this paper, we proposed stereo matching algorithm by dynamic programming with edges emphasized. Existing algorithms show blur generally at depth discontinuities owing to smoothness constraint and non-existence of matching pixel in occlusion regions. Also it accompanies matching error by lackness of matching information in the untextured regions. This paper defines new cost function to make up for the problems occurred to existing algorithms. It is possible through deriving matching of edges in left and right images to be carried out between edge regions anf deriving that in the other regions to be peformed between the other regions. In case of the possibility that edges can be Produced in a large amount, matching between edge information adds weight to cost function in proportion to Path distance. Proposed algorithm was applied to various images obtained by convergent camera model as well as parallel camera model. As the result, proposed algorithm showed improved performance in the aspect of matching error and processing in the occlusion regions compared to existing algorithms. Also it could improve blur especially in discontinuity regions.

  • PDF

제내지 홍수재해 대피 계획 수립을 위한 도시홍수범람모형(SIMOD) 개발

  • Lee, Suk Ho;Kim, Jin Hyuck;Kang, Dong Ho;Kim, Byung Sik
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2017.05a
    • /
    • pp.81-81
    • /
    • 2017
  • 최근 발생하는 태풍 또는 국지성호우는 단기간에 많은 양의 강우를 동반하고 있으며, 이로인한 내수침수 및 외수범람 피해가 빈번히 발생하고 있다. 이와 같은 홍수피해를 저감하기 위한 하나의 대책으로 내수 또는 외수로 인한 피해를 미리 예측하고 대비하는 방법이 필요하다. 피해를 미리 예측하기 위한 기존의 모델들은 지표유출, 지하유출, 침투, 증발산 등 다양한 강우-유출 알고리즘에 의해 홍수범람모의를 분석하게 된다. 따라서 그 모의시간이 길게 나타나 재난상황을 대처하는 데 문제가 있다. 본 연구에서는 홍수로 인한 제내지의 침수 확산 경로 빠른 시간 안에 모의하기 위하여 여러 가지 알고리즘을 단순화시킨 홍수범람 모형을 개발하였다. 개발된 분포형 홍수범람 모형인 SIMOD(Simplified Inundation MODel)는 홍수가 발생된 시점에서 그리드화된 주변셀로의 홍수전의를 위하여 주변셀과의 경사를 이용하여 차등 분배하는 다중흐름방향법(Multi Direction Method, MDM)과, 하나의 낮은 고도의 셀에서 수위가 높아져 인접셀보다 수위가 증가하면 그 수위는 인접 셀들과 균등해 진다는 가정인 평수가정법(Flat-Water Assumption, FWA)인 두 가지 알고리즘을 이용한다. 개발된 모형의 적합성을 확인하기 위하여 상용 모형인 FLO-2D를 이용하여 각 모의시간별 침수면적과 모형의 구동시간을 비교하였다. 비교결과 초기 1시간을 제외하고 홍수피해 면적이 10% 전후로 나타나 SIMOD의 적용성이 확인되었다. 모의 구동시간의 경우 32시간 모의시 SIMOD는 10분 안에 결과가 나오는 반면 FLO-2D는 1시간 이상 소요되는 것으로 나타났다. 또한 대피계획을 수립하기 위하여 제방붕괴시나리오를 이용한 제내지 침수모의를 실시하였다. 대상지역은 금호강하류 성서산업단지 유역으로 계획홍수위는 200년 빈도 홍수위를 기준으로 하였으며 폭 35m, 높이 7m의 제방파제로 인한 외수위 유입을 가정하여 제내지의 시간별 침수면적 모의하였다. 모의된 결과를 이용하여 시간대별 대피경로를 산정함으로써 홍수로 인한 대피 계획 수립에 적용 가능함을 확인하였다.

  • PDF

An convergence analysis of patent toothbrush (칫솔에 대한 특허 융합분석)

  • Moon, Kyung-Hui;Jeong, Mi-Kyoung;Kim, Jang-Mi
    • Journal of the Korea Convergence Society
    • /
    • v.10 no.7
    • /
    • pp.55-62
    • /
    • 2019
  • This study analyzed 467patent for toothbrush that used for oral hearlth, registered for 10years from 2008 to 2017 at KIPRIS which can search patent. Based on the toothbush composition, 8categories were detailed information was subdivided. As a result showed that the most patents were patent for toothbrush bristle, patent for additional function, patent for electronic toothbrush, patent for toothbrush's head, patent for toothbrush in different form, patent for toothbrush's neck, patent for learning of brushing habits, patent for toothbrush's handle. The patent that has a variety of the section was a patent for additional function, the patent for toothbrush bristle was the highest that is 25 in 2012. The only increasing number of patents compared to toothbrush patents, which are decreasing slightly in 2017, was the Patent for learning of brushing habits and the patent for toothbrush's handle. As a result, from 2009, the number of patents for toothbrushes has increased and varied.

Technology Development Trends Analysis and Development Plan of Unmanned Underwater Vehicle (무인 잠수정 연구 개발 동향 분석 및 발전 방안)

  • Lee, Ji Eun
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.20 no.9
    • /
    • pp.233-239
    • /
    • 2019
  • An unmanned underwater vehicle is a major weapon system that allows surveillance and reconnaissance missions in border areas or threatening areas where enemy submarines are present. Unmanned underwater vehicles can be used to explore underwater resources, predict disasters, and survey the topography of the ocean floor in the civilian fields, while in the defense fields, it can be used for anti-submarine reconnaissance and mine countermeasures. In this paper, we first investigate the main classification of unmanned underwater vehicles, and foreign R&D trends are analyzed based on the main classification criteria by weight, such as portable, light, heavy and large-scale unmanned underwater vehicles. Then we examine the trends in the development of domestic unmanned underwater vehicles. Finally, through the analysis of both domestic and foreign unmanned underwater vehicles, we present future development trends of unmanned underwater vehicles in order to set defense goals to counter the anticipated threats and diversified potential environment.

Analysis of the Hydrological Components of the Seolmacheon Catchment for the Year 2021 (2021년 설마천 유역의 수문성분 분석)

  • Kim, Dong Phil
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2022.05a
    • /
    • pp.409-409
    • /
    • 2022
  • 환경부 홍수통제소의 경우는 전국단위의 강수량(지상, 레이더), 하천수위, 유사량 관측과 국부적으로 증발산량과 토양수분 관측이 이루어지고 있는 상황이며, 기상청 및 다른 공공기관도 각 목적에 맞게 수문기상관측이 이루어지나 유역(또는 지역) 단위의 물순환 과정(강우량, 유출량, 증발산량, 지하수함양량, 토양수분량 등 포함)을 규명하는 조사·연구는 매우 미비한 실정이다. 개별적인 물순환 성분별 수문조사에서 벗어난 전체적인 관점을 고려한 유역단위의 물순환 과정을 규명하는 것은 매우 중요하다. 즉 물순환 성분별 명확한 수문량 산정 결과는 수자원 개발과 물환경 보전에 중요한 정보를 제공할 수 있다. 따라서 물순환 성분별 명확한 분석을 위해서는 중·소규모 유역 단위를 대상으로 지속적이고 신뢰성 있는 자료의 획득과 축적이 중요하므로 중·소규모 유역 단위의 대표성 있는 시험유역의 운영은 매우 의미가 있다고 볼 수 있다. 본 논문에서는 한국건설기술연구원에서 운영하는 설마천 유역(전적비교 수위관측소 기준, 유역 면적 8.48km2, 유로연장 5.59km, 유로경사 2.15%, 경기도 파주시 적성면 소재)의 2021년 수문관측자료를 이용하여 지표수 물순환 성분인 강우량, 하천유출량, 증발산량을 산정하였다. 기본 관측자료인 강우량은 각 지점강우량의 관측자료의 비교·검토 등 품질관리를 통해 자료를 확정하고 유역평균강우량을 산정하였다. 하천수위는 기준수위표와의 검토를 통해 자료를 확정하였으며, 하천유출량은 기존의 유량측정성과와 단면검토를 통해 수위-유량관계곡선식을 개발하고, 확정된 수위자료를 적용하여 산정하였다. 그리고 증발산량은 유역인근 2개 관측소(동두천 파주)의 기상관측자료를 이용하여 잠재증발산량을 산정하여 추정한 값이며, 그 외 지하수 함양량은 관측 지하수위자료의 결측으로 산정에서 제외하였다. 각 물순환 성분별로 생성된 2021년의 설마천 유역(전적비교 수위관측소 기준)의 총강우량은 1,103.6mm이며, 하천유출량은 620.1mm(총강우량 대비 56.2%), 실제증발산량(잠재증발산량 추정값)은 443.0mm(40.1%)이며, 그 외는 유역 손실량이다. 이와 같이 산정된 물순환 성분별 자료는 유역의 물순환 과정 규명을 위한 기초자료로 매우 유용하게 활용될 수 있으며, 유역 물관리를 위한 의사결정 과정에 중요한 역할을 할 수 있을 것으로 기대된다.

  • PDF

A Study on the Setting of Examination Limits for Radiographers in Medical Institutions (의료기관 내 방사선사의 검사 한도 설정에 관한 연구)

  • Jeong-Ho Kim;Gap-Jung Kim
    • Journal of the Korean Society of Radiology
    • /
    • v.17 no.3
    • /
    • pp.401-410
    • /
    • 2023
  • A radiographer is a job in charge of diagnostic imaging equipment, and must contribute to the promotion of public health by suggesting an appropriate level of work. To this end, we intend to present an appropriate level of work through evaluation of human harm according to work, statistical evaluation through questionnaires, and domestic and international trends. In the case of human harm evaluation, considering radiation exposure, 42.6%, shield work, 69.7%, and in the case of magnetic resonance imaging, the maximum length of stay in the examination room should be adjusted to 15 minutes and not exceed 30 times. According to the survey statistics, it was confirmed that the physical and mental burden increased due to the high workload and difficulty compared to working hours. Based on domestic and international trends, it is necessary to adjust the examination standards for domestic radiographers to 36.8% to promote national health through qualitative improvement of radiological examinations. something to do.

Local Imbalance of Emergency Medical Services(EMS): Analyses on 119 EMS Activity Reports of Busan (구급서비스의 지역 불균형: 부산시 119 구급활동일지 분석)

  • Lee, Dalbyul
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.23 no.3
    • /
    • pp.161-173
    • /
    • 2020
  • This study analyzed local imbalances in the supply and demand of emergency medical services in Busan using the 119 emergency activity reports of the Busan Fire & Disaster Headquarters. The data for EMS activity reports in 2017 was converted into Jimgyegu units. The spatial distribution of the indicators representing the local imbalance of emergency demand and supply (number of reports, number of reports relative to the population, average coefficient of variation and outlier of on-site arrival time, and number of dispatches outside the jurisdiction) was analyzed using Hotspot analysis of GIS spatial statistics analysis. As a result of the analysis, the hot spot area and the cold spot area where both supply and demand of emergency services are concentrated were clearly distinguished. This means that the supply and demand of emergency services in Busan are locally unbalanced. In particular, there was a difference in the demand and supply of emergency services in the original downtown and its surrounding areas, and in the outskirts of Busan.