The Experts below are selected from a list of 35055 Experts worldwide ranked by ideXlab platform
Renhui Ding - One of the best experts on this subject based on the ideXlab platform.
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Design and experimental study of an effective, low-cost, naturally ventilated radiation shield for monitoring surface air temperature
Meteorology and Atmospheric Physics, 2020Co-Authors: Yang Jie, Deng Xuan, Liu Qingquan, Renhui DingAbstract:Accurate near-surface air temperature is demanded for climate change research. To reduce the air temperature observation error, this paper presents a novel radiation shield. First, a computational fluid dynamics (CFD) method is applied to obtain an optimum design of the radiation shield. Next, the CFD method is used to obtain quantitative radiation errors. Then, a neural network model is used to obtain a radiation error Correction Equation. Finally, observation experiments are conducted to vertify the actual performance of the shield and the corresponding Correction Equation. Experimental results show that the mean radiation error of the shield proposed in this paper is approximately 0.04 °C. In addition, the comparison between the radiation errors provided by the experiments and the radiation errors given by the Correction Equation show that the mean absolute error (MAE) and the root mean square error (RMSE) are 0.012 °C and 0.015 °C, respectively. The radiation error of the radiation shield proposed in this paper may be 1–2 orders of magnitude lower than the radiation errors of the traditional instruments.
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Computational Fluid Dynamics Analysis on Radiation Error of Surface Air Temperature Measurement
International Journal of Thermophysics, 2016Co-Authors: Jie Yang, Qingquan Liu, Renhui DingAbstract:Due to solar radiation effect, current air temperature sensors inside a naturally ventilated radiation shield may produce a measurement error that is 0.8 K or higher. To improve air temperature observation accuracy and correct historical temperature of weather stations, a radiation error Correction method is proposed. The Correction method is based on a computational fluid dynamics (CFD) method and a genetic algorithm (GA) method. The CFD method is implemented to obtain the radiation error of the naturally ventilated radiation shield under various environmental conditions. Then, a radiation error Correction Equation is obtained by fitting the CFD results using the GA method. To verify the performance of the Correction Equation, the naturally ventilated radiation shield and an aspirated temperature measurement platform are characterized in the same environment to conduct the intercomparison. The aspirated temperature measurement platform serves as an air temperature reference. The mean radiation error given by the intercomparison experiments is 0.23 K, and the mean radiation error given by the Correction Equation is 0.2 K. This radiation error Correction method allows the radiation error to be reduced by approximately 87 %. The mean absolute error and the root mean square error between the radiation errors given by the Correction Equation and the radiation errors given by the experiments are 0.036 K and 0.045 K, respectively.
Jie Yang - One of the best experts on this subject based on the ideXlab platform.
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An E-type Temperature Sensor for Upper Air Meteorology
Nanotechnology and Precision Engineering, 2018Co-Authors: Shangbang Han, Wei Dai, Qingquan Liu, Xu Han, Jie YangAbstract:ABSTRACT An E-type high-precision temperature sensor, which is adopted for upper air meteorology, was proposed in this paper. A computational fluid dynamics (CFD) method was implemented to analyze temperature rise induced by solar radiation at different altitudes and solar radiation intensities. A temperature rise Correction Equation was obtained by fitting the CFD results using a Broyden-Fletcher-Goldfarb-Shanno (BFGS) method. To verify the performance of the temperature sensor, an experimental platform was constructed. Through simulations and experiments, the relationship among the altitude, solar radiation intensity and radiation temperature rise was obtaned. The root-mean-square error (RMSE) between the temperature rise derived from the Correction Equation and that derived from the experiments is 0.013 K. The sample determination coefficient r2 of the solar radiation error Correction Equation is 0.9975.
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Computational Fluid Dynamics Analysis on Radiation Error of Surface Air Temperature Measurement
International Journal of Thermophysics, 2016Co-Authors: Jie Yang, Qingquan Liu, Renhui DingAbstract:Due to solar radiation effect, current air temperature sensors inside a naturally ventilated radiation shield may produce a measurement error that is 0.8 K or higher. To improve air temperature observation accuracy and correct historical temperature of weather stations, a radiation error Correction method is proposed. The Correction method is based on a computational fluid dynamics (CFD) method and a genetic algorithm (GA) method. The CFD method is implemented to obtain the radiation error of the naturally ventilated radiation shield under various environmental conditions. Then, a radiation error Correction Equation is obtained by fitting the CFD results using the GA method. To verify the performance of the Correction Equation, the naturally ventilated radiation shield and an aspirated temperature measurement platform are characterized in the same environment to conduct the intercomparison. The aspirated temperature measurement platform serves as an air temperature reference. The mean radiation error given by the intercomparison experiments is 0.23 K, and the mean radiation error given by the Correction Equation is 0.2 K. This radiation error Correction method allows the radiation error to be reduced by approximately 87 %. The mean absolute error and the root mean square error between the radiation errors given by the Correction Equation and the radiation errors given by the experiments are 0.036 K and 0.045 K, respectively.
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A temperature error Correction method for a naturally ventilated radiation shield
Journal of Atmospheric and Solar-Terrestrial Physics, 2016Co-Authors: Jie Yang, Qingquan Liu, Wei Dai, Rrenhui DingAbstract:Abstract Due to solar radiation exposure, air flowing inside a naturally ventilated radiation shield may produce a measurement error of 0.8 °C or higher. To improve the air temperature observation accuracy, a temperature error Correction method is proposed. The Correction method is based on a Computational Fluid Dynamics (CFD) method and a Genetic Algorithm (GA) method. The CFD method is implemented to analyze and calculate the temperature errors of a naturally ventilated radiation shield under various environmental conditions. Then, a temperature error Correction Equation is obtained by fitting the CFD results using the GA method. To verify the performance of the Correction Equation, the naturally ventilated radiation shield and an aspirated temperature measurement platform are characterized in the same environment to conduct the intercomparison. The aspirated temperature measurement platform serves as an air temperature reference. The mean temperature error given by measurements is 0.36 °C, and the mean temperature error given by Correction Equation is 0.34 °C. This Correction Equation allows the temperature error to be reduced by approximately 95%. The mean absolute error (MAE) and the root mean square error (RMSE) between the temperature errors given by the Correction Equation and the temperature errors given by the measurements are 0.07 °C and 0.08 °C, respectively.
Russell Poole - One of the best experts on this subject based on the ideXlab platform.
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temperature quenching of cdom fluorescence sensors temporal and spatial variability in the temperature response and a recommended temperature Correction Equation
Limnology and Oceanography-methods, 2012Co-Authors: Elizabeth Ryder, Eleanor Jennings, Elvira De Eyto, Mary Dillane, Caitriona Nicaonghusa, Donald C Pierson, Karen Moore, Martin Rouen, Russell PooleAbstract:Field-based instruments measuring chromophoric dissolved organic matter (CDOM) fluorescence are often used as a proxy for dissolved organic carbon concentrations in lakes and streams. CDOM fluorescence yield is, however, affected by water temperature at the time of measurement, a factor which varies on both diel and seasonal timescales. A temperature Correction must therefore be applied to these data. We present data on temporal and site-specific variability in temperature quenching of CDOM fluorescence for water from a humic lake and one of its main inflows in the west of Ireland. In addition, we present a temperature compensation Equation and show that this Equation is an improvement on methods previously proposed.
Erik Dick - One of the best experts on this subject based on the ideXlab platform.
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mach uniformity through the coupled pressure and temperature Correction algorithm
Journal of Computational Physics, 2005Co-Authors: Krista Nerinck, Ja Vierendeels, Erik DickAbstract:We present a new type of algorithm: the coupled pressure and temperature Correction algorithm. It is situated in between the fully coupled and the fully segregated approach, and is constructed such that Mach-uniform accuracy and efficiency are obtained. The essential idea is the separation of the convective and the acoustic/thermodynamic phenomena: a convective predictor is followed by an acoustic/thermodynamic corrector. For a general case, the corrector consists of a coupled solution of the energy and the continuity Equations for both pressure and temperature Corrections. For the special case of an adiabatic perfect gas flow, the algorithm reduces to a fully segregated method, with a pressure-Correction Equation based on the energy Equation. Various test cases are considered, which confirm that Mach-uniformity is obtained.
Mingbo Liu - One of the best experts on this subject based on the ideXlab platform.
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multiobjective stochastic economic dispatch with variable wind generation using scenario based decomposition and asynchronous block iteration
IEEE Transactions on Sustainable Energy, 2016Co-Authors: Mingbo LiuAbstract:We investigated a multiobjective stochastic economic dispatch (MOSED) problem considering variable wind power integration. We transformed this problem into an equivalent large-scale multiobjective deterministic optimization model based on the scenario method. We simultaneously minimized power purchase costs and polluting gas emissions. We introduced the normal boundary intersection (NBI) method to convert the multiobjective optimization (MOO) model into a series of single-objective optimization (SOO) problems, which we solved using the interior-point method (IPM). In the process used to solve each SOO problem, we rearranged the coefficient matrix of the Correction Equation in the block bordered diagonal form (BBDF) according to the sequence of the forecast scenario and sampling scenarios. Thus, we were able to decompose this Correction Equation further into a number of low-dimensional Equations corresponding to the forecast scenario and sampling scenarios, respectively, and solve them using the asynchronous block iteration method. Furthermore, we implemented the proposed algorithm on an IEEE 39-bus system and a real-provincial power system, and built a parallel computational framework on high-performance clusters to demonstrate the enhancements in computational speed and the reduced memory requirements obtained by parallelization. Through this framework, one can obtain scheduling of the outputs of generators on a day-ahead basis.
