• 제목/요약/키워드: sum of temperature

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기상인자(氣象因子)에 의한 우리나라 삼림수종(森林樹種)의 생육범위(生育範圍) 및 적지적수(適地適樹)에 관한 연구(研究) (Studies on the Growth Range and Optimum Site Determination of the Tree Species Using Climatological Factors in Korea)

  • 노의래
    • 한국산림과학회지
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    • 제62권1호
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    • pp.1-18
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    • 1983
  • 수종별(樹種別) 생육온도(生育温度) 범위(範圍)를 조사분석(調査分析) 하므로써 조림예정지(造林豫定地)에 대한 올바른 수종(樹種) 선택방법(選擇方法)을 제시(提示)하고자, 30년간(年間)의 일(日) 평균기상자료(平均氣象資料)를 이용(利用)하여, 생육기(生育期)(3~10월(月))의 일(日) 평균기온합계(平均氣温合計), 일(日) 평균상대습도합계(平均相對濕度合計), 일(日) 평균일조시간합계(平均日照時間合計)와 휴면기(休眠期)(11~2월(月))의 일(日) 평균기온합계(平均氣温合計), 일(日) 평균상대습도합계(平均相對濕度合計), 일(日) 평균(平均) 최저기온합계(最低氣温合計)를 조사(調査)하여 우리나라 지도(地圖)에 등지선(等指線)으로 표시(表示)하였다. 조림예정지(造林豫定地)에 대한 생육기(生育期) 일(日) 평균기온합계(平均氣温合計)와 휴면기(休眠期) 일(日) 평균최저기온합계(平均最低氣温合計)를 추정(推定)하기 위하여 우리나라를 6개(個) 지역(地域)으로 나누어, 각각(各各) 이에 상응(相應)하는 추정식(推定式)을 다중회귀직선식(多重回歸直線式)으로 유도(誘導)하였다. 정대현(鄭臺鉉)과 이우철(李愚喆)의 우리 나라 수목(樹木)의 수직(垂直) 및 수평분포표(水平分布表)를 기준(基準)으로 수종별(樹種別) 생육범위(生育範圍)를 일(日) 평균기온합계(平均氣温合計)와 일(日) 평균최저기온합계치(平均最低氣温合計値)에 의하여 나타냈다.

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Temperature distribution analysis of steel box-girder based on long-term monitoring data

  • Wang, Hao;Zhu, Qingxin;Zou, Zhongqin;Xing, Chenxi;Feng, Dongming;Tao, Tianyou
    • Smart Structures and Systems
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    • 제25권5호
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    • pp.593-604
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    • 2020
  • Temperature may have more significant influences on structural responses than operational loads or structural damage. Therefore, a comprehensive understanding of temperature distributions has great significance for proper design and maintenance of bridges. In this study, the temperature distribution of the steel box girder is systematically investigated based on the structural health monitoring system (SHMS) of the Sutong Cable-stayed Bridge. Specifically, the characteristics of the temperature and temperature difference between different measurement points are studied based on field temperature measurements. Accordingly, the probability density distributions of the temperature and temperature difference are calculated statistically, which are further described by the general formulas. The results indicate that: (1) the temperature and temperature difference exhibit distinct seasonal characteristics and strong periodicity, and the temperature and temperature difference among different measurement points are strongly correlated, respectively; (2) the probability density of the temperature difference distribution presents strong non-Gaussian characteristics; (3) the probability density function of temperature can be described by the weighted sum of four Normal distributions. Meanwhile, the temperature difference can be described by the weighted sum of Weibull distribution and Normal distribution.

Environmental Characteristics of Ondal Cave(I)

  • Byeon, Tae-Geun
    • 동굴
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    • 제85호
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    • pp.18-20
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    • 2008
  • To find out the natural environmental characteristics of Ondal Cave, temperature, humidity, wind speed and water temperature have been investigated. When compared to other caves, in sum, Ondal Cave has shown no significant difference interms of natural environment. Inparticular, Ondal Cave was higher than other limestone caves by 1-2$^{\circ}C$ in terms of water temperature due to high inflow of river water nearby.

기체-액체 크로마토그래피에서 화합물의 머무름 지표의 예측에 관한 연구 (Prediction of Retention Indices of Various Compounds in Gas-Liquid Chromatography)

  • 차기원;이덕재
    • 대한화학회지
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    • 제38권2호
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    • pp.108-121
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    • 1994
  • OV-1701 모세관 컬럼과 OV-1모세관 컬럼을 사용하여 컬럼온도 150, 180, $210^{\circ}C$에서 알칸, 방향족, 알코올, 아민, 케톤, 알데히드 및 고리 화합물의 머무름 지표값을 구하였다. 기능기에 의한 머무름 인자(GRF)와 구조변화에 따른 머무름 인자(SRF)는 기능기가 없는 비교 화합물로부터 계산하였다. f번째 기능기에 따른 $GRF_f$를 구하는 식은 $GRF_f\;=\;I_{obs}-(100Z +\sum\limits_{i{\neq}f}GRF_i+{\sum}SRF_i$)와 같다. 마찬가지로 f번째의 구조변화에 따른 $SRF_i$를 구하는 식은 $SRF_f\;=\;I_{obs}-(100Z + {\sum}GRFi + \sum\limits_{i{\neq}f}SRF_i$)와 같다. 계산된 머무름 지표값과 측정값과의 차이는 OV-1701컬럼에서는 ${\pm}2$, OV-1컬럼에서는 ${\pm}3$이내였다. 또한 온도변화에 따른 기능기와 구조변화에 따른 머무름 인자 $\Delta_{ xi}$$\Delta_{ yi}$값을 기능기가 없는 비교 화합물 로부터 계산하였다. f번째 기능기에 따른 $GRF_f$를 구하는 식은 ${\Delta}x_f$ = $\Delta'/^{\circ}C+ \sum\limits_{i{\neq}f}{\Delta}xi +{\sum}{\Delta}yi$ 와 같다. 마찬가지로 f번째의 구조변화에 따른$SRF_f$를 구하는 식은 ${\Delta}yi ={\Delta}'/^{\circ}C+{\sum}{\Delta}xi + \sum\limits_{i{\neq}f}{\Delta}yi$와 같다. 계산된 ${\Delta}xi$ 값과 측정값과의 오차는 OV-1701 컬럼에는 ${\pm}18%$, OV-1컬럼에는 ${\pm}17%$였다.

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남부지역에서 콩의 적기파종 대비 후기 파종이 생육과 수량에 미치는 영향 (Effect of Growth and Yield of Soybean on Late-Sowing Compared to Optimal Sowing in the Southern Region of South Korea)

  • 김예린;김종혁;노일래
    • 한국작물학회지
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    • 제69권1호
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    • pp.61-69
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    • 2024
  • 남부지방(진주)에서 콩 생태형에 따라 적기파종 이후 파종 시기를 달리하였을 때 온도와 일장이 생육일수 및 수량에 미치는 영향을 조사한 결과는 다음과 같다. 1. 적기파종 이후 파종시기를 달리하여 파종하였을 때 모든 생태형에서 출현일, 개화소요일수, 전체 생육일수는 단축되었다. 2. 일장과 온도가 생육일수에 미치는 영향을 다중회귀분석으로 분석한 결과 파종~개화기까지 소요일수는 일장과 온도 모두 정의 상관이였고, 개화기~수확기까지 소요일수는 일장은 정의 상관, 온도는 부의 상관이 있었다. 3. 추정 회귀모형은 파종~개화까지 소요일수(Y) = 3.177 + (0.030 × (누적일장 + 적산온도)), 개화기~수확기까지 소요일수는 (Y) = 20.945 + (0.021 × (누적일장+적산온도))인 것으로 나타났다. 4. 수량은 적기파종에서 가장 높았고 적기파종 이후 늦게 파종할수록 수량이 급격히 감소하여 조생종은 7월 20일, 중만생종은 7월 10일 이전까지는 파종을 해야 급격한 수량감소를 피할 수 있을 것으로 보인다.

총채널 불확실도를 적용한 원전 노심출구온도의 운전가능 판정기준 (Operating Criteria of Core Exit Temperature in Nuclear Power Plant with using Channel Statistical Allowance)

  • 성제중;윤덕주;하상준
    • 한국안전학회지
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    • 제29권6호
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    • pp.166-171
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    • 2014
  • Nuclear power plants are equipped with the reactor trip system (RTS) and the engineered safety features actuation system (ESFAS) to improve safety on the normal operation. In the event of the design basis accident (DBA), a various of post accident monitor(PAM)systems support to provide important details (e.g. Containment pressure, temperature and pressure of reactor cooling system and core exit temperature) to determine action of main control room (MCR). Operator should be immediately activated for the accident mitigation with the information. Especially, core exit temperature is a critical parameter because the operating mode converts from normal mode to emergency mode when the temperature of core exit reaches $649^{\circ}C$. In this study, uncertainty which was caused by exterior environment, characteristic of thermocouple/connector and accuracy of calibrator/indicator was evaluated in accordance with ANSI-ISA 67.04. The square root of the sum of square (SRSS) methodology for combining uncertainty terms that are random and independent was used in the synthesis. Every uncertainty that may exist in the hardware which is used to measure the core exit temperature was conservatively applied and the associative relation between the elements of uncertainty was considered simultaneously. As a result of uncertainty evaluation, the channel statistical allowance (CSA) of single channel of core exit temperature was +1.042%Span. The range of uncertainty, -0.35%Span ($-4.05^{\circ}C$) ~ +2.08%Span($24.25^{\circ}C$), was obtained as the operating criteria of core exit temperature.

회체가스중합모델에 기초한 연소가스의 파장별 복사 성질 (WSGGM-Based Spectral Modeling for Radiation Properties of Combustion Products)

  • 김옥중;송태호
    • 대한기계학회논문집B
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    • 제23권5호
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    • pp.628-636
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    • 1999
  • This work describes the low-resolution spectral modeling of the water vapor, carbon dioxide and their mixtures by applying the weighted-sum-of-gray-gas-gases model (WSGGM) to each narrow band. Proper modeling scheme of gray gas absorption coefficients vs temperature relation is suggested. Comparison between the modeled emissivity calculated from this relation and the 'true' emissivity obtained from the high temperature statistical narrow band parameters is made for a few typical narrow bands. Low resolution spectral intensities from one-dimensional layers are also obtained and examined for uniform, parabolic and boundary layer type temperature profiles using the obtained WSGGM's with several gray gases. The results are compared with the narrow band spectral intensities obtained by a narrow band model-based code with Curtis-Godson approximation. Good agreement is found between them. Data bases including optimized modeling parameters and total and low-resolution spectral weighting factors are developed for water vapor, carbon dioxide and their mixtures. This model and obtained data bases, available from the authors' Internet site, can be appropriately applied to any radiative transfer equation solver.

표면온도 측정에 의한 아크용접공정의 부최적제어 (Suboptimal control of arc welding process using surface temperature measurement)

  • 부광석;조형석
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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    • pp.322-326
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    • 1989
  • This paper describes design procedure of suboptimal control to minimize a performance index which is represented as sum of square output error and the heat input power in arc welding process. Heat input and temperature of a fixed point on the surface of the material are concerned as input and output of the process, repectively. The suboptimal control law considered here in is a proportional plus integral type and is implemented by using only the output variables available from sensor which is also optimally located in a fixed point w.r.t. a moving weld touch.

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삼중효용 흡수사이클의 성능특성 평가 (evaluation of Performance Characteristic on Triple Effect Absorption Cycle)

  • 권오경
    • Journal of Advanced Marine Engineering and Technology
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    • 제22권6호
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    • pp.782-791
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    • 1998
  • This paper presents a computer simulation of five types of triple effect absorption cycles employ-ing the refrigerant absorbent combinations of NH3/LiNO3 low-pressure type NH3/LiNO3+H2O/LiBr binary two-stage type series flow cycle and two types of parallel flow cycle for H2O/LiBr. The absorption systems is investigated through cycle simulation to obtain the system characteristics with the cooling water inlet temperature approach temperature of absorber loss temperature of absorber and chilled water outlet temperature. The most important characteristic temperature of absorber and chilled water outlet temperature. The most important characteristic of NH3/LiNO3 low-pressure type and a NH3/LINO3+H2O/LiBr binary two-stage type is that it obtains a coefficient of performance higher than the sum of the performance coefficients of its part operating independently. As a result of this analysis the optimum designs and operating conditions were determined based on the operating conditions and the coefficient of performance.

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농업재해 예측을 위한 신 기후변화 시나리오의 농업기상자료 구축 - 111개 농업주요지점을 대상으로 - (Construction of Agricultural Meteorological Data by the New Climate Change Scenario for Forecasting Agricultural Disaster - For 111 Agriculture Major Station -)

  • 주진환;정남수;서명철
    • 한국농공학회논문집
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    • 제55권6호
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    • pp.87-99
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    • 2013
  • For analysis of climate change effects on agriculture, precise agricultural meteorological data are needed to target period and site. In this study, agricultural meteorological data under new climate change scenario (RCP 8.5) are constructed from 2011 to 2099 in 111 agriculture major station suggested by Rural Development Administration (RDA). For verifying constructed data, comparison with field survey data in Suwon shows same trend in maximum temperature, minimum temperature, average temperature, and precipitation in 2011. Also comparison with normals of daily data in 2025, 2055, and 2085 shows reliability of constructed data. In analysis of constructed data, we can calculate sum of days over temperature and under temperature. Results effectively show the change of average temperature in each region and odd days of precipitation which means flood and dry days in target region.