基于基础地理数据统计的长三角城市主城区空间格局扩展研究

在快速城镇化时期,城市主城区的空间格局变化最为显著,以其复杂性和扩展性为突出特征。研究其扩展变化对认识城镇化、优化城市空间结构等具有重要意义。本文在基础地理数据统计的基础上,对长三角城市主城区2002~2012年的空间扩展进行了分析,探索影响其演变的若干因素。     

河流型国家湿地公园功能区规划方法探析

国家湿地公园总体规划的核心工作是功能区划分,功能区划分直接影响到相关的保护和恢复工程规划,也为湿地公园的建设布局指明了方向。功能区规划前实地调查工作的重点为理清水系脉络、确定核心资源、找出威胁因子,归纳了4种适合于河流型国家湿地公园功能区划的区划方式,为湿地公园功能区规划提供参考模式。     

Observing Magnetic Fields in Star-Forming Regions

Magnetic field strengths and directions can be estimated using many different observational techniques that span a wide range of wavelengths. Each observational method favours different regimes of scale size, density and other physical conditions. The available techniques and their ranges of applicability are briefly described and the current status of observations is reviewed, with particular emphasis on high-resolution observations of star-forming regions.     

Probing the growth of supermassive black holes at z > 6 with LOFAR

H  ii regions surrounding supermassive black holes (SMBHs) in an otherwise still neutral intergalactic medium (IGM) are likely to be the most easily detectable sources by future 21-cm experiments like LOFAR. We have made predictions for the size distribution of such H  ii regions for several physically motivated models for BH growth at high redshift and compared this to the expected LOFAR sensitivity to these sources. The number of potentially detectable H  ii regions does not only depend on the ionization state of the IGM and the decoupling of the spin temperature of the neutral hydrogen from the cosmic microwave background temperature, but is also strongly sensitive to the rate of growth of BHs at high redshift. If the SMBHs at redshift 6 were built up via continuous Eddington-limited accretion from low mass seed BHs at high redshift, then LOFAR is not expected to detect isolated QSO H  ii regions at redshifts much larger than 6, and only if the IGM is still significantly neutral. If the high-redshift growth of BHs starts with massive seed BHs and is driven by short-lived accretion events following the merging of BH hosting galaxies then the detection of H  ii regions surrounding SMBHs may extend to redshifts as large as 8–9 but is still very sensitive to the redshift to which the IGM remains significantly neutral. The most optimistic predictions are for a model where the SMBHs at z > 6 have grown slowly. H  ii regions around SMBHs may then be detected to significantly larger redshifts.     

河南省电子政务空间信息服务系统建设与典型应用

介绍了河南省电子政务空间信息服务系统的项目背景、系统总体设计，论述了数据处理与集成建库所涉及的一些关键技术，并以中原城市群空间信息服务系统为典型应用，作了进一步的探讨。     

New giant H ii regions in the southern sky

We present results of a search for giant H  ii regions in southern galaxies. Using high-resolution spectra, obtained with the Magellan Inamori Kyocera Echelle (MIKE) at the Las Campanas Magellan II telescope, we were able to resolve the emission-line profiles and determine the intrinsic velocity dispersion of the ionized gas. Out of four observed regions, selected from previous CCD narrow-band photometry, we detected three H  ii regions showing supersonic velocity dispersion, characteristic of giant H  ii regions, and their location in diagnostic diagrams suggests that a powerful starburst is the source of ionization energy.