In this paper the Wilson nonconforming finite element is employed to solve Sobolev and viscoelasticity type equations. By means of post-processing technique, global superconvergence estimates are obtained for quasi-un...In this paper the Wilson nonconforming finite element is employed to solve Sobolev and viscoelasticity type equations. By means of post-processing technique, global superconvergence estimates are obtained for quasi-uniform rectangular meshes. Finally, an error correction scheme is presented.展开更多
Two kinds of measurement errors have been observed in the recently developed UAT-2 ultrasonic anemometer.One is the flow distortion produced by a"blocking effect",and the other is the angle of attack caused ...Two kinds of measurement errors have been observed in the recently developed UAT-2 ultrasonic anemometer.One is the flow distortion produced by a"blocking effect",and the other is the angle of attack caused by the vertical misalignment of the instrument.Here,we study these errors and discuss the possible correction methods.Via a wind tunnel experiment and numerical simulation,a 3D calibration matrix was developed to correct the"blocking effect".In the field test,the angle of attack was detected by an inclinometer settled on the reference plane of the anemometer,and the instrumental misalignment or tilt was corrected by a coordinate transformation.The combined use of an inclinometer and the proposed correction method may help find a new approach for vertical velocity correction.展开更多
文摘In this paper the Wilson nonconforming finite element is employed to solve Sobolev and viscoelasticity type equations. By means of post-processing technique, global superconvergence estimates are obtained for quasi-uniform rectangular meshes. Finally, an error correction scheme is presented.
基金The National Basic Research Program of China(Grant No.2010CB951804)The Strategy Guide for the Specific Task of the Chinese Academy of Sciences(Grant No.XDA10010403)+2 种基金The National Natural Science Foundation of China(Grant No.41375018)Special finance from the China Meteorological Administration(Grant No.GYHY200706034)The National Science and Technology Pillar Program(Grant No.2008BAC37B02)
文摘Two kinds of measurement errors have been observed in the recently developed UAT-2 ultrasonic anemometer.One is the flow distortion produced by a"blocking effect",and the other is the angle of attack caused by the vertical misalignment of the instrument.Here,we study these errors and discuss the possible correction methods.Via a wind tunnel experiment and numerical simulation,a 3D calibration matrix was developed to correct the"blocking effect".In the field test,the angle of attack was detected by an inclinometer settled on the reference plane of the anemometer,and the instrumental misalignment or tilt was corrected by a coordinate transformation.The combined use of an inclinometer and the proposed correction method may help find a new approach for vertical velocity correction.