The dynamic load characteristics of a proton exchange membrane fuel cell（PEMFC） with a dead-ended anode were studied. In a 70 h experiment, the effects of anode pressure, operating temperature, and relative humidity...The dynamic load characteristics of a proton exchange membrane fuel cell（PEMFC） with a dead-ended anode were studied. In a 70 h experiment, the effects of anode pressure, operating temperature, and relative humidity of the cathode on the performances of the fuel cell were investigated. The obtained results show that, with different relative humidity of the cathode at 65 ℃, dynamic loading has little effect on the performances of fuel cell and the electrochemically active surface area（ECSA）. However, the fuel cell operating under dynamic load is unstable when the relative humidity is 50%, and at 50 ℃ with 100% relative humidity, applying a dynamic load has a significant influence on the fuel cell performances. Scanning electron microscopy（SEM） showed that both the upstream and middle catalyst layers of the cell were unchanged, whereas the downstream cathode catalyst layer thinned as a response to dynamic load.展开更多
To reduce the complexity of large-scene high-resolution maps while using the dead-end information distributed in the unmanned vehicle driving environment,we propose a novel non-uniform quadtree map-building method inc...To reduce the complexity of large-scene high-resolution maps while using the dead-end information distributed in the unmanned vehicle driving environment,we propose a novel non-uniform quadtree map-building method including dead-end semantic information extraction.By utilizing quadtree data structures,submaps and a positive-order tree depth organization approach,our proposed map can adapt to the large-scale high-resolution requirement and expand more easily to larger environments.To verify the practicality of our proposed map,we have successfully implemented map matching and path planning in real environments.Additionally,we effectively extract the dead-end semantic information that widely distributes in the environment,which can help unmanned vehicles avoid collisions and improve the search efficiency of the planning procedure.We evaluate our method with KITTI datasets,CARLA Simulator,and our self-collected real-world datasets.The experimental results show that our proposed method significantly reduces the complexity of large-scale high-resolution maps,effectively extracts dead-end semantic information,and has good practicality in real environments.The implementation of our method is released here:https://github.com/biter0088/Non-uniform-quadtree-map.展开更多
基金Funded by the National Natural Science Foundation of China(Nos.51476119 and 51576147)the Natural Science Foundation of Hubei Province(No.2016CFA041)the Fundamental Research Funds for the Central Universities(No.2017 IVA 031)
文摘The dynamic load characteristics of a proton exchange membrane fuel cell（PEMFC） with a dead-ended anode were studied. In a 70 h experiment, the effects of anode pressure, operating temperature, and relative humidity of the cathode on the performances of the fuel cell were investigated. The obtained results show that, with different relative humidity of the cathode at 65 ℃, dynamic loading has little effect on the performances of fuel cell and the electrochemically active surface area（ECSA）. However, the fuel cell operating under dynamic load is unstable when the relative humidity is 50%, and at 50 ℃ with 100% relative humidity, applying a dynamic load has a significant influence on the fuel cell performances. Scanning electron microscopy（SEM） showed that both the upstream and middle catalyst layers of the cell were unchanged, whereas the downstream cathode catalyst layer thinned as a response to dynamic load.
文摘To reduce the complexity of large-scene high-resolution maps while using the dead-end information distributed in the unmanned vehicle driving environment,we propose a novel non-uniform quadtree map-building method including dead-end semantic information extraction.By utilizing quadtree data structures,submaps and a positive-order tree depth organization approach,our proposed map can adapt to the large-scale high-resolution requirement and expand more easily to larger environments.To verify the practicality of our proposed map,we have successfully implemented map matching and path planning in real environments.Additionally,we effectively extract the dead-end semantic information that widely distributes in the environment,which can help unmanned vehicles avoid collisions and improve the search efficiency of the planning procedure.We evaluate our method with KITTI datasets,CARLA Simulator,and our self-collected real-world datasets.The experimental results show that our proposed method significantly reduces the complexity of large-scale high-resolution maps,effectively extracts dead-end semantic information,and has good practicality in real environments.The implementation of our method is released here:https://github.com/biter0088/Non-uniform-quadtree-map.
