• 제목/요약/키워드: temperature estimation

검색결과 1,638건 처리시간 0.024초

화재시 철근 콘크리트 보 내부 온도의 해석적 추정 (Analytical Estimation of Internal Temperature of RC Beam under Fire)

  • 이은주;신미경;강지연;신영수
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
    • /
    • pp.548-551
    • /
    • 2004
  • The main purpose of this study is to estimate the internal temperature of RC beam under fire. For this purpose, the finite difference method was used. In the previous studies, the structural behavior of fire damaged RC beams was investigated through experiments. The result was concluded that The high temperature affects the properties of concrete such as the elastic modulus, the compressive strength. The internal temperature Estimation of the concrete is helpful for understanding the structural behavior of fire damaged RC beams. Especially, high strength concrete has more spalling than normal strength one. So, this study is performed analysis of internal temperature of RC beam considering spalling.

  • PDF

콘크리트 고성재료의 수화발열 및 열적특성을 고려한 단열온도상승 예측에 관한 연구 (The estimation of adiabatic temperature rise of concrete considered hydration heat generation and thermal properties of constituents)

  • 손명수;강석화;이양수;박연동;김훈
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 1998년도 봄 학술발표회 논문집(I)
    • /
    • pp.155-160
    • /
    • 1998
  • In this study, the estimation method of adiabatic temperature rise of concrete was developed by using hydration heat generation of mineral compounds of clinker and pozzolans. Specific heat considered the effects of mix proportion and temperature was calculated with experimental data. The adiabatic temperature rise calculated by developed method were compared with experiments in which many types of cement and admixtures were used. As the results of this study, it was found that the developed method could calculate adiabatic temperature rise of concrete accurately without the experiment.

  • PDF

Capacitance Estimation of DC-Link Capacitor Considering Temperature Effect

  • 보성사;김경현;이동춘;이교범;김장목
    • 전력전자학회:학술대회논문집
    • /
    • 전력전자학회 2010년도 하계학술대회 논문집
    • /
    • pp.156-157
    • /
    • 2010
  • This paper proposes a correction method of capacitance estimation considering the temperature effect for the DC-link capacitor banks in three-phase AC/DC PWM converters. In this work, a sensing circuit using a temperature sensor is designed for measuring the operating temperature. Capacitance value is corrected considering the measured temperature. This method has been implemented in experiment.

  • PDF

1차원 유한요소법 모델을 이용한 초음파 Hyperthermia의 온도분포에 관한 연구 (A Study on the Estimation of Temperature Distribution in Ultrasonic Hyperthermia by 1-Dimensional FEM Model)

  • 하재규;성굉모
    • 한국음향학회지
    • /
    • 제6권1호
    • /
    • pp.29-38
    • /
    • 1987
  • Hyperthermia의 임상 응용에서 측정할 수 있는 온도치는 수 점의 온도치로 제한되는데 효과적인 치료를 위해서는 그 외의 점에서의 정확한 온도분포를 알아야 할 필요가 있다. 이를 위하여, 본 논문에서는 생체 열전달 방정식을 1차원 2경계치 문제로 단순화시켜 계산시간을 줄였으며 Galerkin법을 이용하여 그 근사해률 구하였다. 그 결과를 동심환 초음파 변환기에 적용하여 축방향의 온도분포를 계산하였으며 측정된 수 점의 온도로부터 축방향의 온도분포를 추정할 수 있는 알고리즘을 제시하였다.

  • PDF

기온예상치를 고려한 모델에 의한 주간최대전력수요예측 (Weekly maximum power demand forecasting using model in consideration of temperature estimation)

  • 고희석;이충식;김종달;최종규
    • 대한전기학회논문지
    • /
    • 제45권4호
    • /
    • pp.511-516
    • /
    • 1996
  • In this paper, weekly maximum power demand forecasting method in consideration of temperature estimation using a time series model was presented. The method removing weekly, seasonal variations on the load and irregularities variation due to unknown factor was presented. The forecasting model that represent the relations between load and temperature which get a numeral expected temperature based on the past 30 years(1961~1990) temperature was constructed. Effect of holiday was removed by using a weekday change ratio, and irregularities variation was removed by using an autoregressive model. The results of load forecasting show the ability of the method in forecasting with good accuracy without suffering from the effect of seasons and holidays. Percentage error load forecasting of all seasons except summer was obtained below 2 percentage. (author). refs., figs., tabs.

  • PDF

한반도 주변해역 대기환경에 대한 싱글채널 온도추정 알고리즘의 불확도 추정 (Uncertainty Estimation of Single-Channel Temperature Estimation Algorithm for Atmospheric Conditions in the Seas around the Korean Peninsula)

  • 이종혁;강경웅;백승일;김원국
    • 대한원격탐사학회지
    • /
    • 제39권3호
    • /
    • pp.355-361
    • /
    • 2023
  • 지구 표면에 대한 정보는 기상 및 대기 역학의 이해나 인간을 포함한 동물에 큰 영향을 미치는 극한 열현상에 대응함에 있어서 핵심적인 지구 물리량이다. 지구 영역에 대한 온도를 추정하기 위하여 위성에 탑재된 열적외 센서가 널리 활용되어 왔는데, 정밀한 활용을 위해서는 온도 추정 과정의 불확도에 대한 이해가 선행되어야 한다. 하지만 온도추정 불확도에 영향을 미치는 많은 요소 중에서 한반도 주변의 환경 하에서의 온도추정 알고리즘의 불확도 산정에 대한 연구는 미미하였다. 본 연구에서는 한반도 주변의 대기 및 해양 조건하에서 범용성이 높은 single-channel 알고리즘의 불확도를 추정하는 연구를 수행하였다. 알고리즘의 입력자료로 필요한 재분석자료(reanalysis)의 영향성을 평가하기 위하여 두 가지의 재분석자료, 즉 fifth generation of European Centre for Medium-Range Weather Forecasts reanalysis of the global climate and weather (ERA5)와 Modern-Era Retrospective analysis for Research and Applications-2 (MERRA-2)를 사용하였고, 복사전달모델은 MODerate resolution atmospheric TRANsmission (MODTRAN)을 사용하였다. MODTRAN 모의와 온도 추정 정확도 검증에 사용되는 현장 관측 수온은 한반도 인근 해역에 위치한 해양 기상 부이(buoy)로부터 획득했다. 실험 결과, 알고리즘 불확도는 대기 수증기량에 따라서 선형에 가깝게 증가하는 것을 확인하였고, 가장 건조한 조건에서는 약 0.35K 그리고 평균적으로 0.45K 가량의 불확도가 발생함을 확인하였다. 이러한 결과는 재분석자료의 종류에 상관없이 유사하게 도출되어 알고리즘이 가지는 순수한 불확도라고 추정할 수 있었다.

온도변화에 강인한 EPB 시스템의 모델기반 고장검출 방법 (Robust Model Based Fault Detection of EPB System for Varying Temperature)

  • 문병준;박종국
    • 한국자동차공학회논문집
    • /
    • 제17권5호
    • /
    • pp.26-30
    • /
    • 2009
  • In this paper, a robust model based fault detection for varying temperature is proposed, To develop a robust force estimation model, it needs temperature information because the force sensor's output is affected by a temperature variation. If an EPB system does not include a temperature sensor, the model has a much larger error than an EPB system with a built-in temperature sensor. Therefore, the temperature is estimated by using Ohm's law. The force model is applied with a motor current, battery voltage, operation mode, and the estimated temperature to detect a force sensor's abnormal signal fault. The residual is calculated by comparing the value of the measured force and the estimated force. Fault information is collected by using the output of the evaluated residual with the adaptive thresholds. A proposed robust model based fault detection for varying temperature was verified by HILS (Hardware in the Loop Simulation).

기계학습을 이용한 노면온도변화 패턴 분석 (Analysis of Road Surface Temperature Change Patterns using Machine Learning Algorithms)

  • 양충헌;김승범;윤천주;김진국;박재홍;윤덕근
    • 한국도로학회논문집
    • /
    • 제19권2호
    • /
    • pp.35-44
    • /
    • 2017
  • PURPOSES: This study suggests a specific methodology for the prediction of road surface temperature using vehicular ambient temperature sensors. In addition, four kind of models is developed based on machine learning algorithms. METHODS : Thermal Mapping System is employed to collect road surface and vehicular ambient temperature data on the defined survey route in 2015 and 2016 year, respectively. For modelling, all types of collected temperature data should be classified into response and predictor before applying a machine learning tool such as MATLAB. In this study, collected road surface temperature are considered as response while vehicular ambient temperatures defied as predictor. Through data learning using machine learning tool, models were developed and finally compared predicted and actual temperature based on average absolute error. RESULTS : According to comparison results, model enables to estimate actual road surface temperature variation pattern along the roads very well. Model III is slightly better than the rest of models in terms of estimation performance. CONCLUSIONS : When correlation between response and predictor is high, when plenty of historical data exists, and when a lot of predictors are available, estimation performance of would be much better.

다중모델추정기법을 이용한 HEV/EV용 리튬이온전지의 잔존충전용량 추정 (Multiple Model Adaptive Estimation of the SOC of Li-ion battery for HEV/EV)

  • 정해봉;김영철
    • 전기학회논문지
    • /
    • 제60권1호
    • /
    • pp.142-149
    • /
    • 2011
  • This paper presents a new state of charge(SOC) estimation of large capacity of Li-ion battery (LIB) based on the multiple model adaptive estimation(MMAE) method. We first introduce an equivalent circuit model of LIB. The relationship between the terminal voltage and the open circuit voltage(OCV) is nonlinear and may vary depending on the changes of temperature and C-rate. In this paper, such behaviors are described as a set of multiple linear time invariant impedance models. Each model is identified at a temperature and a C-rate. These model set must be obtained a priori for a given LIB. It is shown that most of impedances can be modeled by first-order and second-order transfer functions. For the real time estimation, we transform the continuous time models into difference equations. Subsequently, we construct the model banks in the manner that each bank consists of four adjacent models. When an operating point of cell temperature and current is given, the corresponding model bank is directly determined so that it is included in the interval generated by four operating points of the model bank. The MMAE of SOC at an arbitrary operating point (T $^{\circ}C$, $I_{bat}$[A]) is performed by calculating a linear combination of voltage drops, which are obtained by four models of the selected model bank. The demonstration of the proposed method is shown through simulations using DUALFOIL.

Inverse Brightness Temperature Estimation for Microwave Scanning Radiometer

  • Park, Hyuk;Katkovnik, Vladimir;Kang, Gum-Sil;Kim, Sung-Hyun;Choi, Jun-Ho;Choi, Se-Hwan;Jiang, Jing-Shan;Kim, Yong-Hoon
    • 대한원격탐사학회지
    • /
    • 제19권1호
    • /
    • pp.53-59
    • /
    • 2003
  • The passive microwave remote sensing has progressed considerably in recent years Important earth surface parameters are detected and monitored by airborne and space born radiometers. However the spatial resolution of real aperture measurements is constrained by the antenna aperture size available on orbiting platforms and on the ground. The inverse problem technique is researched in order to improve the spatial resolution of microwave scanning radiometer. We solve a two-dimensional (surface) temperature-imaging problem with a major intention to develop high-resolution methods. In this paper, the scenario for estimation of both radiometer point spread function (PSF) and target configuration is explained. The PSF of the radiometer is assumed to be unknown and estimated from the observations. The configuration and brightness temperature of targets are also estimated. To do this, we deal with the parametric modeling of observation scenario. The performance of developed algorithms is illustrated on two-dimensional experimental data obtained by the water vapor radiometer.