• 제목/요약/키워드: temperature correction

검색결과 480건 처리시간 0.025초

수요관리사업자에 대한 외부온도 변화에 따른 수요반응 CBL의 편익에 관한 연구 (A Study on Benefit Sides of Demand Response Customer Baseline with Outdoor Temperature Variable about Load Aggregator)

  • 김성철;송하나
    • 조명전기설비학회논문지
    • /
    • 제28권3호
    • /
    • pp.44-50
    • /
    • 2014
  • This paper describes reasonable methods by considering change of outdoor temperature into Customer Baseline Load(CBL) of Demand Resources in Smart Demand Resource Market, which controls peak power demand and maintains reliability of power system. The Smart Demand Resouce Market, which KPX(Korea Power Exchange) implement, is explained and then effects for CBL calculated by considering temperature correction factor are established. Finally, four methods for calculation of CBL are proposed and those results are compared and analyzed.

진동신호기반 손상검색기법과 온도변화의 영향 (Temperature Effects on Vibration-Based Damage Detection Method)

  • 김정태;류연선;조현만;윤정방;이진학
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2003년도 추계학술대회논문집
    • /
    • pp.608-613
    • /
    • 2003
  • In this paper, the variability of modal properties caused by temperature effects is assessed to adjust modal data used for frequency-based damage detection in plate-girder bridges. First, experiments on model plate-girder bridges are described. Next, the relationship between temperature and natural frequencies is assessed and a set of empirical frequency-correction formula are analyzed for the test structure. Finally, a frequency-eased method is used to locate and estimate severity of damage in the test structure using experimental modal data which are adjusted by the frequency-correction formula. Here, local damage in beam-type structures is detected by using measured frequencies and analytical mode shapes.

  • PDF

가압기 밀림관 환경피로평가를 위한 피로보정계수 적용에 관한 연구 (A Study on Application of Fatigue Correction Factor for Environmental Fatigue Evaluation of Pressurizer Surge Line)

  • 양준석;박치용;강선예
    • 대한기계학회논문집A
    • /
    • 제33권10호
    • /
    • pp.1151-1157
    • /
    • 2009
  • Nuclear power plants applying for the continued operation over design life are required to address the effects of reactor water environment in fatigue design requirement of the ASME Code. Reactor water environmental effects are generally evaluated by calculating fatigue correction factors on fatigue usage. This paper describes the application for pressurizer surge line of environmental fatigue correction factors and the strain rate impact in the application. From this paper, the environmental fatigue correction factors resulted from the assumption of a step change in temperature are especially compared with those calculated from the data measured during plant startup. As a conclusion of this paper, the design transient conditions applied to the fatigue design may be conservative in case of the environmental fatigue evaluation.

등가재령방법에 의한 혼화재 종류별 콘크리트의 압축강도 증진해석 (Estimation of the Compressive Strength of the Concrete incorporating Mineral Admixture based on the Equivalent Age Method)

  • 한민철;한천구
    • 한국건축시공학회지
    • /
    • 제7권1호
    • /
    • pp.71-77
    • /
    • 2007
  • This paper is to investigate the effect of the curing temperature on strength development of concrete incorporating cement kiln dust(CKD) and blast furnace slag (BS) quantitatively. Estimation of the compressive strength of the concrete was conducted using the equivalent age equation and the rate constant model proposed by Carino. Correction of Carino model was studied to secure the accuracy of strength development estimation by introducing correction factors regarding rate constant and age. An increasing curing temperature results in an increase in strength at early age, but with the elapse of age, strength development at high curing temperature decreases compared with that at low curing temperature. Especially, the use of BS has a remarkable strength development at early age and even at later age, high strength is maintained due to accelerated pozzolanic activity resulting from high temperature. Whereas, at low curing temperature, the use of BS leads to a decrease in compressive strength. Accordingly, much attention should be paid to prevent strength loss at low temperature. Based on the strength development estimation using equivalent age equation, good agreements between measured strength and calculated strength are obtained.

IMPROVING EMISSIVITY ESTIMATION IN RETRIEVING LAND SURFACE TEMPERATURE WITH MODIS DATA

  • Lin, Tang-Huang;Liu, Gin-Rong;Tsai, Fuan;Hsu, Ming-Chang
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
    • /
    • pp.337-340
    • /
    • 2007
  • Many researches conducted to investigate the relationship between surface emissivity and surface temperature in the past two decades and pointed out that the emissivity play a key role in applying remote sensing data to retrieve surface temperature. The task of surface temperature estimation is so important in many research fields, such as earth energy budgets, evapotranspiration, drought, global change and heat island effect. Therefore, it is indispensable to develop an effective and accurate technique to estimate the emissivity for accurate surface temperature estimations. This study developed an improved emissivity estimation technique for the use of surface temperature retrievals with MODIS data. The result of applying this improved technique using Band 31 of MODIS shows that the accuracy of estimated surface temperatures will be improved. This study also uses MODIS data observed in 2005 to establish the relationship between the surface emissivity correction factor and NDVI. Through the use of these correction factors, the land surface temperature can be retrieved more accurate with MODIS data.

  • PDF

펄스 플라즈마 제트내에 있는 구리원자의 발광 스펙트럼 정밀 보정 (Precise correction of the copper emission spectra from the pulsed plasma jet)

  • 김종욱;고동섭;오승묵
    • 한국광학회지
    • /
    • 제12권2호
    • /
    • pp.115-120
    • /
    • 2001
  • 본 연구는 고온 고압의 전열(electrothermal)플라즈마내에 존재하는 구리원자의 발광 스펙트럼을 정량적으로 분석하는 방법에 대해 논하였다. 플라즈마는 플라즈마 발생장치내에 설치되어 있는 모세관 양단의 두 개의 전극이 방전함으로써 발생하며 고속으로 대기를 향해 전파해 나간다. 플라즈마의 특성을 분석하기 위해서는 플라즈마의 여기온도나 전자밀도와 같은 물리량의 측정이 필요하다. 그러나 여기온도나 전자밀동와 직접적으로 관련이 있는 발광 스펙트럼은 분광시스템의 파장에 따른 서로다른 응답 특성 때문에 왜곡되어질 수 있다 따라서 본 연구에서는 펄스 플라즈마 제트로부터 얻은 구리원자의 발광 스펙트럼을 정밀하게 보정하는 방법을 제시하였다.

  • PDF

막여과 정수처리 공정에서 온도보정차압 식의 파울링 지표로서의 활용성 검토 (Applicability of Temperature Correction Trans-membrane Pressure as a Fouling Index of Membrane Water Treatment Process)

  • 김민재;임재림;이경혁;이영주;김수한
    • 상하수도학회지
    • /
    • 제30권1호
    • /
    • pp.1-8
    • /
    • 2016
  • Temperature correction trans-membrane pressure (TC-TMP) is frequently used as a fouling index in membrane water treatment plants. TC-TMP equation is derived based on an assumption that the total membrane resistance (i.e. the sum of the intrinsic membrane resistance and fouling resistance) is not affected by temperature. This work verified the validity of this assumption using microfiltration (MF) and ultrafiltration (UF) membranes with and without fouling. The foulants used in the work were kaolin (inorganic) and humic acid (organic). The intrinsic resistances of MF and UF membranes remains at constant values regardless of temperature change. When the same amount of foulants were accumulated on the membrane, inorganic fouling resistance with kaolin was constant regardless of temperature change while organic fouling resistance with humic acid decreased at higher temperatures, which means that TC-TMP cannot be used as a fouling index when organic fouling occurs in a real field application. Since TC-TMP underestimates the amount of fouling at higher temperatures, more attention should be necessary in the operation of membrane water treatment plant in a hotter season like summer.

콘크리트의 형상비 및 온도변화에 따른 부착강도 특성평가 (Evaluation of Bond Strength Properties with Changing the Aspect Ratio and Temperature of Concrete)

  • 김현석;정원경;오한진;박준영;김형배
    • 한국도로학회논문집
    • /
    • 제20권3호
    • /
    • pp.19-26
    • /
    • 2018
  • PURPOSES : The main purpose of this study is suggest of field bond strength evaluation method for more objective evaluation method through Evaluation of Bond Strength Properties with changing aspect ratio and temperature. METHODS : The evaluation is laboratory bond strength test. Using the core machine, the pull-off test method ; the bond strength test of interface layer the universal testing machine. RESULTS : As a result of the laboratory bond strength evaluation, it was verified that the bond strength by aspect ratio decreases linearly with increasing aspect ratio and the bond strength properties by temperature change existed at high and low temperature condition relative to odinary temperature condition. CONCLUSIONS : According to the results of laboratory bond strength evaluation, the field bond strength evaluation results suggest applying the proposed correction factor (0.8, 1.0, 1.4, 1.9) according to aspect ratio(0.5, 0.1, 1.5, 2.0), For more objective evaluation of the bond strength, it is analyzed that the evaluation value is within $6{\sim}32^{\circ}C$ and the result can be obtained within 5% of the coefficient of variation.

온도 의존적 재료물성치를 고려한 개선된 그린함수 기반 열응력 계산 (Thermal Stress Calculations Using Enhanced Green's Function Considering Temperature-dependent Material Properties)

  • 한태송;허남수;전현익;하승우;조선영
    • 한국생산제조학회지
    • /
    • 제24권5호
    • /
    • pp.535-540
    • /
    • 2015
  • We propose an enhanced Green's function approach to predict thermal stresses by considering temperature-dependent material properties. We introduce three correction factors for the maximum stress, the time taken to reach maximum stress, and the time required to attain steady state based on the Green's function results for each temperature. The proposed approach considers temperature-dependent material properties using correction factors, which are defined as polynomial expressions with respect to temperatures based on Green's functions, that we obtain from finite-element (FE) analyses at each temperature. We verify the proposed approach by performing detailed FE analyses on thermal transients. The Green's functions predicted by the proposed approach are in good agreement with those obtained from FE analyses for all temperatures. Moreover, the thermal stresses predicted using the proposed approach are also in good agreement with the FE results, and the proposed approach provides better predictions than the conventional Green's function approach using constant, time-independent material properties.