随着地球观测进入大数据时代,传统的数据管理技术已经难以适应大数据需求,Open Data Cube(ODC)作为新型的开源的地球观测数据管理与分析平台,适合进行时间序列数据的高性能计算和探索性数据分析,是亚大区域综合地球观测系统AOGEOSS的重...随着地球观测进入大数据时代,传统的数据管理技术已经难以适应大数据需求,Open Data Cube(ODC)作为新型的开源的地球观测数据管理与分析平台,适合进行时间序列数据的高性能计算和探索性数据分析,是亚大区域综合地球观测系统AOGEOSS的重要技术支撑平台。但当前ODC对国产卫星影像支持不友好,缺乏自动化管理和数据组织工具,使用ODC进行国产卫星影像数据管理的技术不成熟。因此,本文以高分一号卫星影像为例,通过开发ODC_GFTool中间件和自定义高分卫星影像产品格式探索ODC框架下国产影像数据自动化管理流程,最后以鄱阳湖为试验区,进行了基于ODC框架的水体提取应用实验,论证了ODC框架下国产卫星数据存取的可行性,研究结果表明相较于传统的数据处理工具ODC具有明显的效率优势,能够为AOGEOSS基础设施建设和国产卫星影像数据管理提供一定的参考。展开更多
As a basic optical device, the optical directional coupler (ODC) is basically used as optical splitters, optic switches and so on. A novel ODC employing surface plas- mon polaritons (SPPs) is proposed for high integra...As a basic optical device, the optical directional coupler (ODC) is basically used as optical splitters, optic switches and so on. A novel ODC employing surface plas- mon polaritons (SPPs) is proposed for high integration. The finite difference time domain (FDTD) method is adopted to simulate and analyze its properties. Results show that the ODC proposed here follows the general regulations of a conventional dielectric ODC, but its transverse size is of nanoscale, which improves the optical integration greatly. For 1550 nm and 1310 nm input wavelengths, when the coupling region length (L) equals half of its coupling length, the Excess Loss is respectively 0.57 dB and 0.56 dB, which is practical in applications. So the research on the present ODC is of some practical importance.展开更多
In this paper, Ductility Dip Cracking (DDC) susceptibility in Inconel600 companion Filler Metal 82 (FM82) under different stress states is investigated. Inconel600 is a Ni-Cr-Fe alloy with excellent resistance to ...In this paper, Ductility Dip Cracking (DDC) susceptibility in Inconel600 companion Filler Metal 82 (FM82) under different stress states is investigated. Inconel600 is a Ni-Cr-Fe alloy with excellent resistance to general corrosion, localized corrosion, and stress corrosion, which has been widely used in nuclear power plants. However, the companion FM82 has been shown to be susceptible to DDC in welding process. To resolve the problem, this work is mainly focused on evaluating DDC susceptibility in FM82 in welding process. First of all, Strain to Fracture (STF) test is used to achieve the DDC criterion under simple stress state, and the formation mechanism of DDC was explained. Real welding is a process with complex stress state. Later, to get the DDC susceptibility under complex stress state, models about multi-pass welding were built up by means of finite element method. According to numerical simulation results, relationship of deformation and temperature history is achieved. Moreover, susceptible locations and moments could be determined associated with STF results. The simulation results fairly agree with welding experiment from another research.展开更多
The taxonomic status of the Sulawesi endemic Geomalia heinrichi has long been debated, and it has variously been treated as a babbler (Timaliidae) or a turdid (Turdidae). We estimated the phylogeny of 43 taxa in the f...The taxonomic status of the Sulawesi endemic Geomalia heinrichi has long been debated, and it has variously been treated as a babbler (Timaliidae) or a turdid (Turdidae). We estimated the phylogeny of 43 taxa in the family Turdidae based on the mitochondrial cytochrome b gene and the nuclear myoglobin intron 2 and ornithine decarboxylase introns 6–7. Geomalia heinrichi was shown to be part of the Zoothera clade with high support. We propose that Geomalia is transferred to Zoothera under the name Zoothera heinrichi.展开更多
文摘随着地球观测进入大数据时代,传统的数据管理技术已经难以适应大数据需求,Open Data Cube(ODC)作为新型的开源的地球观测数据管理与分析平台,适合进行时间序列数据的高性能计算和探索性数据分析,是亚大区域综合地球观测系统AOGEOSS的重要技术支撑平台。但当前ODC对国产卫星影像支持不友好,缺乏自动化管理和数据组织工具,使用ODC进行国产卫星影像数据管理的技术不成熟。因此,本文以高分一号卫星影像为例,通过开发ODC_GFTool中间件和自定义高分卫星影像产品格式探索ODC框架下国产影像数据自动化管理流程,最后以鄱阳湖为试验区,进行了基于ODC框架的水体提取应用实验,论证了ODC框架下国产卫星数据存取的可行性,研究结果表明相较于传统的数据处理工具ODC具有明显的效率优势,能够为AOGEOSS基础设施建设和国产卫星影像数据管理提供一定的参考。
基金the Project of Guangdong Natural Science Funds for the Research on Nano-integrated Waveguide Devices Based On Surface Plasmon Polariton (Grant No. 07117866)the Key Project of the Natural Science Foundation of Guangdong Province of China (Grant No. 05200534)
文摘As a basic optical device, the optical directional coupler (ODC) is basically used as optical splitters, optic switches and so on. A novel ODC employing surface plas- mon polaritons (SPPs) is proposed for high integration. The finite difference time domain (FDTD) method is adopted to simulate and analyze its properties. Results show that the ODC proposed here follows the general regulations of a conventional dielectric ODC, but its transverse size is of nanoscale, which improves the optical integration greatly. For 1550 nm and 1310 nm input wavelengths, when the coupling region length (L) equals half of its coupling length, the Excess Loss is respectively 0.57 dB and 0.56 dB, which is practical in applications. So the research on the present ODC is of some practical importance.
基金Acknowledgements This research was sponsored by the National Natural Science Foundation of China (Grant No. 50975176).
文摘In this paper, Ductility Dip Cracking (DDC) susceptibility in Inconel600 companion Filler Metal 82 (FM82) under different stress states is investigated. Inconel600 is a Ni-Cr-Fe alloy with excellent resistance to general corrosion, localized corrosion, and stress corrosion, which has been widely used in nuclear power plants. However, the companion FM82 has been shown to be susceptible to DDC in welding process. To resolve the problem, this work is mainly focused on evaluating DDC susceptibility in FM82 in welding process. First of all, Strain to Fracture (STF) test is used to achieve the DDC criterion under simple stress state, and the formation mechanism of DDC was explained. Real welding is a process with complex stress state. Later, to get the DDC susceptibility under complex stress state, models about multi-pass welding were built up by means of finite element method. According to numerical simulation results, relationship of deformation and temperature history is achieved. Moreover, susceptible locations and moments could be determined associated with STF results. The simulation results fairly agree with welding experiment from another research.
基金the Chinese Academy of Sciences Visiting Professorship for Senior International Scientists (No. 2011T2S04)
文摘The taxonomic status of the Sulawesi endemic Geomalia heinrichi has long been debated, and it has variously been treated as a babbler (Timaliidae) or a turdid (Turdidae). We estimated the phylogeny of 43 taxa in the family Turdidae based on the mitochondrial cytochrome b gene and the nuclear myoglobin intron 2 and ornithine decarboxylase introns 6–7. Geomalia heinrichi was shown to be part of the Zoothera clade with high support. We propose that Geomalia is transferred to Zoothera under the name Zoothera heinrichi.