The use of visible and infrared remote sensing images to calculate the water area is an effective means to grasp the basic situation of water resources,and water segmentation is the premise of statistics.Generally,the...The use of visible and infrared remote sensing images to calculate the water area is an effective means to grasp the basic situation of water resources,and water segmentation is the premise of statistics.Generally,the edge features of the water in the remote sensing images are complex.When the traditional morphology is used for image segmentation,it is easy to change the image edge and affect the accuracy of image segmentation because the fixed structuring elements are used to perform morphological operations on the image.To segment water in the remote sensing image accurately,a remote sensing image water segmentation method based on adaptive morphological elliptical structuring elements is proposed.Firstly,the eigenvalue and eigenvector of the image are estimated by linear structure tensor,and the elliptical structuring elements are constructed by the eigenvalue and eigenvector.Then adaptive morphological operations are defined,combining the close operation to eliminate the influence of dark detail noise on water without overstretching the water edge,so that the water edge can be maintained more accurately.Finally,on this basis,the water area can be segmented by gray slice.The experimental results show that the proposed method has higher segmentation accuracy and the average segmentation error is less than 1.43%.展开更多
The effective cathode flow field design can realize the internal water balance and higher current density output of proton exchange membrane fuel cells(PEMFC).Therefore,a segmented water management flow field is propo...The effective cathode flow field design can realize the internal water balance and higher current density output of proton exchange membrane fuel cells(PEMFC).Therefore,a segmented water management flow field is proposed in this study,i.e.a half separated-half coupled cathode(HSHC)flow field which has two inlets but just one outlet.A 3D numerical PEMFC model is applied to study the effect of the HSHC flow field on PEMFC performance and its operating strategy in terms of operating conditions.The study results are shown as follows:Compared with the two conventional cathode flow fields,the HSHC flow field improves the water balance along the channel and increases the current density by 17.1%at a cathode stoichiometry of 3.25.It is because the HSHC flow field can overcome the water loss at channels upstream and the water accumulation at channels downstream.The draw water phenomenon(DWP)in the HSHC flow field is observed,which is mainly affected by the water vapor pressure of channel.Based on the DWP,cooling channel inlet flow rates can be used to adjust water balance,but severe water loss should be avoided.In addition,the inlet temperature control in HSHC flow field should be that cell temperature>cathode channel inlet temperature>cooling channel inlet temperature>ambient temperatures for better water balance.展开更多
Water leakage inspection in the tunnels is a critical engineering job that has attracted increasing concerns.Leakage area detection via manual inspection techniques is time-consuming and might produce unreliablefinding...Water leakage inspection in the tunnels is a critical engineering job that has attracted increasing concerns.Leakage area detection via manual inspection techniques is time-consuming and might produce unreliablefindings, so that automated techniques should be created to increase reliability and efficiency. Pre-trainedfoundational segmentation models for large datasets have attracted great interests recently. This paper proposes a novel SAM-based network for accurate automated water leakage inspection. The contributions of thispaper include the efficient adaptation of the SAM (Segment Anything Model) for shield tunnel water leakagesegmentation and the demonstration of the application effect by data experiments. Tunnel SAM Adapter hassatisfactory performance, achieving 76.2 % mIoU and 77.5 % Dice. Experimental results demonstrate that ourapproach has advantages over peer studies and guarantees the integrity and safety of these vital assets whilestreamlining tunnel maintenance.展开更多
基金National Natural Science Foundation of China(No.61761027)Graduate Education Reform Project of Lanzhou Jiaotong University(No.1600120101)。
文摘The use of visible and infrared remote sensing images to calculate the water area is an effective means to grasp the basic situation of water resources,and water segmentation is the premise of statistics.Generally,the edge features of the water in the remote sensing images are complex.When the traditional morphology is used for image segmentation,it is easy to change the image edge and affect the accuracy of image segmentation because the fixed structuring elements are used to perform morphological operations on the image.To segment water in the remote sensing image accurately,a remote sensing image water segmentation method based on adaptive morphological elliptical structuring elements is proposed.Firstly,the eigenvalue and eigenvector of the image are estimated by linear structure tensor,and the elliptical structuring elements are constructed by the eigenvalue and eigenvector.Then adaptive morphological operations are defined,combining the close operation to eliminate the influence of dark detail noise on water without overstretching the water edge,so that the water edge can be maintained more accurately.Finally,on this basis,the water area can be segmented by gray slice.The experimental results show that the proposed method has higher segmentation accuracy and the average segmentation error is less than 1.43%.
基金the financial support for this research from the National Natural Science Foundation of China(52176063)the International Science and Technology projects of Huangpu District of Guangzhou City(2020GH08)the Guangzhou Science and Technology Plan Project(201907010036)。
文摘The effective cathode flow field design can realize the internal water balance and higher current density output of proton exchange membrane fuel cells(PEMFC).Therefore,a segmented water management flow field is proposed in this study,i.e.a half separated-half coupled cathode(HSHC)flow field which has two inlets but just one outlet.A 3D numerical PEMFC model is applied to study the effect of the HSHC flow field on PEMFC performance and its operating strategy in terms of operating conditions.The study results are shown as follows:Compared with the two conventional cathode flow fields,the HSHC flow field improves the water balance along the channel and increases the current density by 17.1%at a cathode stoichiometry of 3.25.It is because the HSHC flow field can overcome the water loss at channels upstream and the water accumulation at channels downstream.The draw water phenomenon(DWP)in the HSHC flow field is observed,which is mainly affected by the water vapor pressure of channel.Based on the DWP,cooling channel inlet flow rates can be used to adjust water balance,but severe water loss should be avoided.In addition,the inlet temperature control in HSHC flow field should be that cell temperature>cathode channel inlet temperature>cooling channel inlet temperature>ambient temperatures for better water balance.
基金funded by the National Natural Science Foundation of China(Nos.62171114,52222810)the Fundamental Research Funds for the Central Universities(No.DUT22RC(3)099).
文摘Water leakage inspection in the tunnels is a critical engineering job that has attracted increasing concerns.Leakage area detection via manual inspection techniques is time-consuming and might produce unreliablefindings, so that automated techniques should be created to increase reliability and efficiency. Pre-trainedfoundational segmentation models for large datasets have attracted great interests recently. This paper proposes a novel SAM-based network for accurate automated water leakage inspection. The contributions of thispaper include the efficient adaptation of the SAM (Segment Anything Model) for shield tunnel water leakagesegmentation and the demonstration of the application effect by data experiments. Tunnel SAM Adapter hassatisfactory performance, achieving 76.2 % mIoU and 77.5 % Dice. Experimental results demonstrate that ourapproach has advantages over peer studies and guarantees the integrity and safety of these vital assets whilestreamlining tunnel maintenance.