• 제목/요약/키워드: Safety Estimation

검색결과 1,650건 처리시간 0.03초

금속파편충격에 의한 강판의 가속도신호 특성 (Acceleration Signal Characteristics of Steel Plate Impacted by Metallic Loose Parts)

  • 성게용;윤용구
    • 비파괴검사학회지
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    • 제12권2호
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    • pp.21-29
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    • 1992
  • Acceleration signal characteristics of a steel plate, impacted by steel balls, were studied in an attempt to apply the experimental results to the impact location and mass estimation of metallic loose parts in the cooling system of nuclear power plants. Experimental results show that the variation of maximum acceleration amplitude and impact contact time due to the change of ball mass and impact velocity can be well explained by the Hertz impact theory. The frequency spectral pattern shifted slightly in spite of the increase of impact velocity and impact location. Ball mass, however, strongly affected the frequency spectral pattern. Hence the frequency spectrum can be used for estimation of the mass of unknown loose parts in the cooling system.

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실차 운행정보를 이용한 온실가스 배출량 산정에 관한 연구 (A Study on the Estimation of GHG Emissions using a Real World Vehicle Driving Information)

  • 박건진;김필수;최상진;한용희;이헌주;이갑상;장영기
    • 한국기후변화학회지
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    • 제6권2호
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    • pp.143-158
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    • 2015
  • This study developed the emission intensity estimation method of GHGs by considering the characteristics of the models and time series. The telematics device was installed on the vehicle (OBD-II) to collect information on the operation conditions from each sample vehicle of public authorities. As a result of comparing the mileage distance and fuel consumption, the matching degree is analyzed very high, showed a ${\pm}1{\sim}4%$ error for each vehicle. By comparing driving record diary of vehicles managed by public authorities, this study presents the method that can be used to verify driving information in order to derive the GHGs emission intensity.

Quantitative measures of thoroughness of FBD simulations for PLC-based digital I&C system

  • Lee, Dong-Ah;Kim, Eui-Sub;Yoo, Junbeom
    • Nuclear Engineering and Technology
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    • 제53권1호
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    • pp.131-141
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    • 2021
  • Simulation is a widely used functional verification method for FBD programs of PLC-based digital I&C system in nuclear power plants. It is difficult, however, to estimate the thoroughness (i.e., effectiveness or quality) of a simulation in the absence of any clear measure for the estimation. This paper proposes two sets of structural coverage adequacy criteria for the FBD simulation, toggle coverage and modified condition/decision coverage, which can estimate the thoroughness of simulation scenarios for FBD programs, as recommended by international standards for functional safety. We developed two supporting tools to generate numerous simulation scenarios and to measure automatically the coverages of the scenarios. The results of our experiment on five FBD programs demonstrated that the measures and tools can help software engineers estimate the thoroughness and improve the simulation scenarios quantitatively.

국내 천연가스배관 유지관리를 위한 목표신뢰도 적용사례 (Application of Target Reliability Levels for Maintenance of Domestic Natural Gas Pipelines)

  • 이진한;김정환;조영도;김래현
    • 한국가스학회지
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    • 제22권3호
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    • pp.1-6
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    • 2018
  • 신뢰도기반 설계 및 평가(RBDA) 방법론은 천연가스 배관을 설계하는 최신의 방법 중 하나이다. 신뢰도 목표는 설계와 유지관리 단계에 걸쳐 관계된 한계상태을 충족하는 안전수준을 가지는 지 확인하기 위해 사용된다. 목표 신뢰도는 대누출과 파단과 같은 극한한계상태에 대한 개인적 위험과 사회적 위험에서 사용하는 허용 가능한 위험수준을 적용하여 개발되었다. 본 논문에서 신뢰도 목표는 배관의 생애주기 동안 주기적인 유지관리를 적용함으로써 충족할 수 있음을 보여준다. 사례분석은 국내 천연가스 수송배관에 대한 굴착공사에 따른 손상확률 계산, 부식에 따른 손상확률의 계산, 그리고 재검사 주기의 추정을 포함한다.

해안매립 신도시의 재해 예방관리 네트워크 비젼 (Network vision of disaster prevention management for seashore reclaimed u-City)

  • 안상로
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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    • pp.117-129
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    • 2009
  • This paper studied the safety management network system of infrastructure which constructed smart sensors, closed-circuit television(CCTV) and monitoring system. This safety management of infrastructure applied to bridge, cut slop and tunnel, embankment etc. The system applied to technologies of standardization guidelines, data acquirement technologies, data analysis and judgment technologies, system integration setup technology, and IT technologies. It was constructed safety management network system of various infrastructure to improve efficient management and operation for many infrastructure. Integrated safety management network system of infrastructure consisted of the real-time structural health monitoring system of each infrastructure, integrated control center, measured data transmission using i of tet web-based, collecting data using sf ver, early alarm system which the dangerous event of infrastructure occurred. Integrated control center consisted of conference room, control room to manage and analysis the data, server room to present the measured data and to collect the raw data. Early alarm system proposed realization of warning and response within 5 minute or less through development of sensor-based progress report and propagation automation system using the media such as MMS, VMS, EMS, FMS, SMS and web services of report and propagation. Based on this, the most effective u-Infrastructure Safety Management System is expected to be stably established at a less cost, thus making people's life more comfortable. Information obtained from such systems could be useful for maintenance or structural safety evaluation of existing structures, rapid evaluation of conditions of damaged structures after an earthquake, estimation of residual life of structures, repair and retrofitting of structures, maintenance, management or rehabilitation of historical structures.

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부등침하의 영향이 반영된 철근콘크리트 구조물 잔존수명 평가모델 (Remaining Service Life Estimation Model for Reinforced Concrete Structures Considering Effects of Differential Settlements)

  • 이상훈;한선진;조해창;이윤정;김강수
    • 한국구조물진단유지관리공학회 논문집
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    • 제24권1호
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    • pp.133-141
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    • 2020
  • 한국시설안전공단에서는 '시설물의 안전관리에 관한 특별법'에 따라 철근콘크리트 구조물의 안전점검 및 정밀안전진단을 실시하도록 제시하고 있다. 그러나 한국시설안전공단 안전점검 및 정밀안전진단 세부지침의 평가방법에서는 평가결과를 등급으로 제시하기 때문에 구조물의 잔존수명을 알 수 없으며 부등침하가 구조물의 잔존수명에 미치는 영향을 반영하지 못한다. 따라서, 이 연구에서는 부등침하의 영향이 반영된 구조물의 잔존수명 평가모델을 제시하고자 하였다. 부등침하와 각 변위의 상관관계를 나타내는 기존의 연구를 바탕으로 부재의 공칭강도에 부등침하의 영향을 반영시키기 위한 식을 제시하였으며, 실제 철근콘크리트 구조물의 현장데이터를 활용하여 부등침하가 구조물의 잔존수명에 미치는 영향을 분석하였다.

지하주차장 성능위주설계의 피난안전성 평가 개선에 관한 연구 (A Study on Improvement of Evacuation Safety Evaluation for Performance Based Design in Underground Parking Lot)

  • 송영주;공일천;김학중
    • 한국화재소방학회논문지
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    • 제33권2호
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    • pp.85-97
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    • 2019
  • 오늘날 인간의 삶의 질 향상과 다양한 욕구를 충족시키기 위한 건축물은 대형화, 고층화, 심층화, 복합화 되는 추세이며, 이에 따른 비정형화된 공간이 새롭게 창출되면서 성능위주설계대상도 증가하고 있다. 성능위주설계의 피난안전성 평가는 ASET과 RSET를 산정 비교하여 RSET이 ASET를 초과하지 않도록 하여야 한다. 그러나 지하 주차장과 같이 구획된 공간의 면적이 넓고 피난경로가 다양한 경우 현재 시행되고 있는 성능위주설계 평가 방법만으로 모든 피난경로에서 안전성을 확보하기 어려운 문제가 있다. 따라서 본 논문에서는 이러한 문제점을 극복하기 위해 현재 사용되고 있는 성능위주설계의 시뮬레이션 설정방법에 대해 먼저 고찰한 다음 지하 주차장을 대상으로 화재시뮬레이션 2가지와 피난시뮬레이션 3가지 경우를 각각 수행하여 6가지 경우에 대한 피난안전성 평가를 실시하고 비교 평가하여 문제점을 살펴보고 개선된 성능위주설계의 피난안전성 평가 방안을 제시한다.

백부자-대체 가능 한약재의 계종버섯에 대한 급성독성시험과 안전성등급화 (Acute toxicity test and safety classification for Termitomyces albuminosus containing pharmacologically similar ingredient of Aconitum koreanum)

  • 안민지;박영철
    • 대한본초학회지
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    • 제32권4호
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    • pp.33-38
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    • 2017
  • Objectives : Termitomyces albuminosus (Berk.) Heim is one of the famous wild edible mushrooms in the southern part of China. It is known that Termitomyces albuminosus, like Aconitum koreanum used in Korean traditional medicine, contains a kind of cerebroside, termitomycesphin, causing a pharmacologic effect on the neuron system. The pharmacologic effect of Termitomyces albuminosus can be used to possibly replace Aconitum koreanum. However, It needs to be certified as safe before it can be used. Here, a single-oral toxicity test and safety classification was conducted to obtain acute information of the toxicity of dried-Termitomyces albuminosus powder and to secure its safety in clinical applications. Methods : In order to calculate approximate lethal dose(ALD), test substance was orally administered to male and female SD-rat at dose levels of 5,000 and 0 (vehicle control) mg/kg (body weight). Based on the result of this toxicity, also the estimation of safety classification was calculated using the HED-based (human equivalent dose) MOS (margin of safety). Results : There were no mortalities, test substances treatment-related clinical signs, no changes in the body or organ weights, and no gross or histopathological findings at 14 days after treatment with test substance. Thus, the approximate lethal dose of dried-Termitomyces albuminosus powder was considered over 5,000 mg/kg in both female and male mice. Conclusions : Based on the limit dose, 5000 mg/kg, it was estimated that dried-Termitomyces albuminosus powder is classified as "Specified class B" indicating that clinical dose is not limited to patients as safe as food.

비행안전구역 건물 높이 평가에서 수치지형도로 제작한 DEM의 활용성 (The Utilization of DEM Made by Digital Map in Height Evaluation of Buildings in a Flying Safety Area)

  • 박종철;김만규;정웅선;한규철;류영기
    • 한국지리정보학회지
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    • 제14권3호
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    • pp.78-95
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    • 2011
  • 본 연구에서는 1:5,000 수치지형도를 이용하여 서로 다른 보간 방법으로 다양한 공간해상도를 갖는 여러 가지 DEM을 제작하였다. 그리고 제작한 다양한 DEM의 수직정확도를 network RTK GPS survey를 통해 획득한 다수의 검사점 자료를 활용하여 평가하였다. 연구 결과 전반적인 RMSE 값, 토지 유형별 RMSE 값 및 단면 평가(profile evaluation) 결과 등을 고려할 때 TIN 기반의 Terrain 방법으로 제작한 DEM이 비행안전구역에서의 신축건물 고도제한 평가에 유용함을 알 수 있었다. 그리고 비행안전구역에서의 신축건물 고도제한 평가에 적합한 DEM의 공간해상도는 3m임을 알 수 있었다. 한편, 제작한 DEM으로 획득한 지형고도 값(elevation value)은 점 추정 값(point estimation value)이 아닌 구간 추정 값(interval estimation value)이다. 이는비행장 주변의 잠재적인 신축 예정 건물의 높이가 그 지역에 설정된 제한 고도 값(height limitation value)에 저촉되는지에 대한 여부를 평가하는 데 활용할 수 있다. 본 연구에서는 구간 추정 값인 신축건물의 높이 값이 제한 고도 값에 저촉될 가능성을 3단계로 나누어 평가하는 방안을 제시하였다 - 1) 저촉 가능성 매우 높음, 2) 저촉 가능성 매우 낮음, 3) 저촉 가능성 판단 어려움. 본 연구의 결과는 비행장 주변 건물 고도제한 평가 관련 지리정보시스템(GIS)을 개발하는 데 중요한 기초를 제공한다. 아울러, 연구지역에 한정된 값이기는 하지만, 2차원 수치지형도를 활용하여 제작한 DEM의 수직정확도 값은 DEM을 이용하고자 하는 연구자들에게 의미 있는 유용한 정보가 될 것이다.

A Collaborative Study to Establish the Second Korean National Reference Standard for Snake Venom

  • Han, Kiwon;Jung, Kikyung;Oh, Hokyung;Song, Hojin;Park, Sangmi;Kim, Ji-Hye;Min, Garam;Lee, Byung-Hwa;Nam, Hyun-sik;Kim, Yang Jin;Ato, Manabu;Jeong, Jayoung;Ahn, Chiyoung
    • Toxicological Research
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    • 제34권3호
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    • pp.191-197
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    • 2018
  • In 2015, a candidate for the second national reference standard (NRS) of Gloydius snake venom was produced to replace the first NRS of Gloydius snake venom. In the present study, the potencies of the candidate were determined by a collaborative study, and the qualification of the candidate was estimated. The potencies of the candidate were determined by measuring the murine lethal titers and lapine hemorrhagic titers of venom against the regional working reference standard (RWRS) for antivenom using the methods described in the previous report for the first NRS of Gloydius snake venom. Three Korean facilities contributed data from a total of 30 independent assays. Subsequently, two foreign national control research laboratories contributed to this collaborative study. The results were calculated using the Reed-Muench method for lethality and determined using a mixed-effects model for hemorrhage. The general common potencies of the lethal and hemorrhagic titers were obtained from the results of the 30 tests performed at three Korean facilities. The results are expressed in micrograms for 1 test dose (TD) with a 95% confidence interval as follows: a lethal titer of $90.13{\mu}g/TD$ (95% confidence interval = $87.39{\sim}92.86{\mu}g$) and a hemorrhagic titer of $10.80{\mu}g/TD$ (95% confidence interval = $10.46{\sim}11.14{\mu}g$). In addition, the candidate preparation showed good quality evaluation according to the results of the quality estimation of the candidate and is judged to be suitable to serve as the Korean NRS for snake venom. In conclusion, the second NRS of Gloydius snake venom was established in this study and will be used for national quality control, including a national lot release test of Korean antivenom products.