结合国际照明委员会(Commission International de l’Eclairage, CIE)颜色系统,首先利用基于卫星多光谱遥感反射率的色度角信息获取方法,得到色度角信息数据集;然后,将色度角数据集与航测数据集匹配,建立基于色度角信息的总叶绿素和悬...结合国际照明委员会(Commission International de l’Eclairage, CIE)颜色系统,首先利用基于卫星多光谱遥感反射率的色度角信息获取方法,得到色度角信息数据集;然后,将色度角数据集与航测数据集匹配,建立基于色度角信息的总叶绿素和悬浮颗粒物浓度反演模型;最后利用现场采集的辽宁大连附近海域高清数码图像进行验证。结果表明:基于色度角信息反演得到的叶绿素a质量浓度、悬浮颗粒物质量浓度的反演模型精度较高,二者与色度角的相关系数R^(2)分别为0.73、0.81,且均与色度角呈负相关关系。该模型可以与无人机、数码相机等系统联动,并与卫星遥感组成立体监测系统,为海洋水质环境监测提供一种新方法。展开更多
Based on numerical simulations,this study highlights the sedimentation and erosion problems around a sand barrier through the relationship between the shear stress of the surface around the sand barrier and the critic...Based on numerical simulations,this study highlights the sedimentation and erosion problems around a sand barrier through the relationship between the shear stress of the surface around the sand barrier and the critical shear stress of sand grains.The numerical simulation results were verified using data measured by the wind tunnel test.The results showed that when the porosity was the same,the size and position of the vortex on the leeward side of the sand barrier were related to the inlet wind speed.As the wind speed increased,the vortex volume increased and the positions of the separation and reattachment points moved toward the leeward side.When the porosity of the sand barrier was 30%,the strength of the acceleration zone above the sand barrier was the highest,and the strength of the acceleration zone was negatively correlated with the porosity.Sand erosion and sedimentation distance were related to wind speed.With an increase in wind speed,the sand grain forward erosion or reverse erosion areas on the leeward side of the sand barrier gradually replaced the sedimentation area.With an increase in porosity,the sand sedimentation distance on the leeward side of the sand barrier gradually shortened,and the sand erosion area gradually disappeared.The sand sedimentation distance on the leeward side of the sand barrier with 30%porosity was the longest.The numerical simulation results were in good agreement with the wind tunnel test results.Based on the sand erosion and sedimentation results of the numerical simulation and wind tunnel test,when the porosity was 30%,the protection effect of the High Density Polyethylene(HDPE)board sand barrier was best.展开更多
文摘结合国际照明委员会(Commission International de l’Eclairage, CIE)颜色系统,首先利用基于卫星多光谱遥感反射率的色度角信息获取方法,得到色度角信息数据集;然后,将色度角数据集与航测数据集匹配,建立基于色度角信息的总叶绿素和悬浮颗粒物浓度反演模型;最后利用现场采集的辽宁大连附近海域高清数码图像进行验证。结果表明:基于色度角信息反演得到的叶绿素a质量浓度、悬浮颗粒物质量浓度的反演模型精度较高,二者与色度角的相关系数R^(2)分别为0.73、0.81,且均与色度角呈负相关关系。该模型可以与无人机、数码相机等系统联动,并与卫星遥感组成立体监测系统,为海洋水质环境监测提供一种新方法。
基金financially supported by the fellowship of the China Postdoctoral Science Foundation(2021M703466)the Natural Science Foundation of Gansu Province,China(20JR10RA231)+1 种基金the Basic Research Innovation Group Project of Gansu Province,China(21JR7RA347)an Special Funds for Guiding Local Scientific and Technological Development by the Central Government(22ZY1QA005)。
文摘Based on numerical simulations,this study highlights the sedimentation and erosion problems around a sand barrier through the relationship between the shear stress of the surface around the sand barrier and the critical shear stress of sand grains.The numerical simulation results were verified using data measured by the wind tunnel test.The results showed that when the porosity was the same,the size and position of the vortex on the leeward side of the sand barrier were related to the inlet wind speed.As the wind speed increased,the vortex volume increased and the positions of the separation and reattachment points moved toward the leeward side.When the porosity of the sand barrier was 30%,the strength of the acceleration zone above the sand barrier was the highest,and the strength of the acceleration zone was negatively correlated with the porosity.Sand erosion and sedimentation distance were related to wind speed.With an increase in wind speed,the sand grain forward erosion or reverse erosion areas on the leeward side of the sand barrier gradually replaced the sedimentation area.With an increase in porosity,the sand sedimentation distance on the leeward side of the sand barrier gradually shortened,and the sand erosion area gradually disappeared.The sand sedimentation distance on the leeward side of the sand barrier with 30%porosity was the longest.The numerical simulation results were in good agreement with the wind tunnel test results.Based on the sand erosion and sedimentation results of the numerical simulation and wind tunnel test,when the porosity was 30%,the protection effect of the High Density Polyethylene(HDPE)board sand barrier was best.
基金Projects(42077254, 51874144) supported by the National Natural Science Foundation of ChinaProjects(cstc2019jcyjmsxm X0488, cstc2021jcyj-msxm X0354) supported by the Natural Science Foundation of Chongqing,China+2 种基金Projects(KJZD-K202201304, KJQN202201314) supported by Science and Technology of Chongqing Municipal Education Commission,ChinaProject (2021M693751) supported by China Postdoctoral Science FoundationProject (P2017JG18) supported by Major Cultivation of Chongqing University of Arts and Sciences,China。
