研究野生动物的空间属性时一般要用到地理信息系统(geographic information system),ArcGIS作为一款功能强大、开放性强、可拓展、可伸缩、多层次的GIS空间分析软件,在野生动物空间分布研究中必不可少。本文从生境适宜性、空间分布与种...研究野生动物的空间属性时一般要用到地理信息系统(geographic information system),ArcGIS作为一款功能强大、开放性强、可拓展、可伸缩、多层次的GIS空间分析软件,在野生动物空间分布研究中必不可少。本文从生境适宜性、空间分布与种群监测、自然保护地设计三个方面介绍了ArcGIS在野生动物空间分布研究中的作用,系统阐述了ArcGIS在野生动物空间分布研究中应用现状和进展,结合云计算、5G多元统计等热点领域对其未来的发展与前景进行了展望。展开更多
A stall warning approach based on aero-acoustic theory is studied in this paper. For this stall warning approach, a parameter Rc is defined to measure the periodicity of the blade-passing signal. Signal simulation is ...A stall warning approach based on aero-acoustic theory is studied in this paper. For this stall warning approach, a parameter Rc is defined to measure the periodicity of the blade-passing signal. Signal simulation is used to investigate the mechanism of the stall warning approach. The results suggest that the value of Rc is influenced by the power of the perturbations. The experiments on a two-stage compressor indicate this stall warning approach can generate a warning signal several seconds before the stall. It is demonstrated in this paper that the stall warning approach can detect the distribution and evolution of stall precursors. According to the distribution of the stall precursors, the partial stall precursor-suppressed casing treatment is applied and realized a stabilization of compressor.展开更多
文摘研究野生动物的空间属性时一般要用到地理信息系统(geographic information system),ArcGIS作为一款功能强大、开放性强、可拓展、可伸缩、多层次的GIS空间分析软件,在野生动物空间分布研究中必不可少。本文从生境适宜性、空间分布与种群监测、自然保护地设计三个方面介绍了ArcGIS在野生动物空间分布研究中的作用,系统阐述了ArcGIS在野生动物空间分布研究中应用现状和进展,结合云计算、5G多元统计等热点领域对其未来的发展与前景进行了展望。
基金supported by China Academy of Launch vehicle Technology (No.51606223)National Natural Science Foundation of China (Nos. 11661141020, 51576008, 51822601 and 51790514)
文摘A stall warning approach based on aero-acoustic theory is studied in this paper. For this stall warning approach, a parameter Rc is defined to measure the periodicity of the blade-passing signal. Signal simulation is used to investigate the mechanism of the stall warning approach. The results suggest that the value of Rc is influenced by the power of the perturbations. The experiments on a two-stage compressor indicate this stall warning approach can generate a warning signal several seconds before the stall. It is demonstrated in this paper that the stall warning approach can detect the distribution and evolution of stall precursors. According to the distribution of the stall precursors, the partial stall precursor-suppressed casing treatment is applied and realized a stabilization of compressor.
