基于MAPGIS的军事指挥系统的设计

介绍了在ＭＡＰＧＩＳ上进行的武警指挥系统的设计,系统采用ＧＩＳ和ＧＰＳ结合的技术,实现了信息管理,信息查询,战术标图,战术计算、作战文书、作战文书、动态目标监控以及三维电子沙盘等功能。     

地下通信管线动态信息管理系统的研制与应用

根据地下通信管线网络的特点与通信部门对管线网络规划、工程设计、维护管理与统计分析的实际需求,以通信主干管线为初始对象,以通信综合网络为终极目标,选用国产优秀地理信息系统基础软件平台———ＭＡＰＧＩＳ进行二次开发,建立地下通信管线动态信息管理系统,并对系统的应用现状与前景作了简要介绍．     

The high-velocity molecular stream in W51B: a ring structure with compact H ii regions

We present ¹³ CO J  = 1 − 0 line observations of the H  ii region complex W51B located in the high-velocity (HV) stream. These observations reveal a filamentary and clumpy structure in the molecular gas. The mean local standard of rest (LSR) velocity ∼ + 65 km s⁻¹ of the molecular gas in this region is greater than the maximum velocities allowed by kinematic Galactic rotation curves. The size and mass of the molecular clouds are ∼ 48 × 17 pc² and ∼ 2.4 × 10⁵ M⊙ respectively. In a position–velocity diagram, molecular gas in the southern part comprises a redshifted ring structure with v _LSR=+ 60 to +73 km s⁻¹. The velocity gradient of this ring is ∼ 0.5 km s⁻¹ pc⁻¹, and the mass is ∼ 6.2 × 10⁴ M⊙. If we assume that the ring is expanding with a uniform velocity, the expansion velocity, radius and kinetic energy are ∼ 7 km s⁻¹, ∼ 13 pc and ∼ 3.0 × 10 ⁴⁹ erg respectively. The kinetic energy and mass spectrum of the ring could be explained by an expanding cylindrical cloud with a centrally condensed mass distribution. The locations of two compact H  ii regions, G49.0−0.3 and G48.9−0.3, coincide with the two molecular clumps in this ring. We discuss star formation, and the mechanism that produced the ring structure.     

S 266: a ring nebula around a Galactic B[e] supergiant?

A narrow-band Hα image and high-resolution spectroscopy have been obtained in order to investigate the nature of S 266 and its central star MWC 137. The analysis of the stellar and nebular spectra suggests that MWC 137 is a B[e] supergiant located ≥ 6 kpc away from the Sun and not a Herbig Ae/Be star, as it has been traditionally classified. Moreover, the morphology and other properties of the nebula suggest that S 266 is a ring nebula, probably produced by the interaction of stellar winds with the ambient interstellar medium or unprocessed ejected matter. This result would imply that S 266 is the first ring nebula around a B[e] supergiant known in the Galaxy.     

Methanol masers and their environment at high resolution

We have used the Australia Telescope Compact Array (ATCA) to make high-resolution images of the 6.7-GHz 5₁ → 6₀A⁺ maser transition of methanol towards 33 sources in the Galactic plane. Including the results from 12 methanol sources in the literature, we find that 17 out of 45 sources have curved or linear morphology. Most of the 17 have a velocity gradient along the line, which is consistent with masers lying in an edge-on circumstellar disc surrounding a massive star. We also made simultaneous continuum observations of the sources at 8.6 GHz, in order to image any associated H  ii region. 25 of the sources are associated with an ultracompact H  ii region, with a detection limit of ∼0.5 mJy beam⁻¹. We argue that the methanol sources without an associated H  ii region represent less massive embedded stars, not an earlier stage in the lifetime of the star, as previously suggested.     

Morphology of star formation regions in irregular galaxies

The location of H  II regions, which indicates the locus of present star formation in galaxies, is analysed for a large collection of 110 irregular galaxies (Irr) imaged in Hα and nearby continuum. The analysis is primarily by visual inspection, although a two-dimensional quantitative measure is also employed. The two different analyses yield essentially identical results. H  II regions appear preferentially at the edges of the light distribution, predominantly on one side of the galaxy, contrary to what is expected from stochastic self-propagating star formation scenarios. This peculiar distribution of star-forming regions cannot be explained by a scenario of star formation triggered by an interaction with extragalactic gas, or by a strong one-armed spiral pattern.     

西双版纳自然保护区纳板河可持续发展信息系统

建立自然保护区是保护自然资源的重要途径,但自然保护区本身也正面临着持续发展的问题,即保护和开发利用上的问题,而在西双版纳热带地区更是突出。地理信息系统的出现,为解决这一矛盾提供了重要的技术手段。开发纳板河可持续发展信息系统（ＮＢＲＳＤＩＳ）是一项复杂的系统工程,采用了结构化系统分析方法对ＮＢＲＳＤＩＳ进行分析与设计。系统的建立,一方面为纳板河自然保护区的科学管理提供决策依据,另一方面,为具有相似地理环境,面临同样问题的国内其它自然保护区开发可持续发展信息系统提供模式和经验     

Seismic hazard assessment for low-seismicity areas — Case study: Northern Germany

The problem of assessing seismic hazard in low-seismicity areas becomes obvious in many practical applications. A typical low-seismicity area, which experienced damaging earthquakes in historical times, is the North German Plain, for which a case study is presented. It is shown how seismic hazard assessments are influenced by different interpretations of historical key earthquakes, changes in b-value as well as variations of the upper bound magnitude assumed for the seismic source regions. The latter strongly influences the hazard results in the case of very low b-values for long return periods.     

自动化地理信息综合的发展现状和趋势

本文在强调地理信息综合对于开发和应用地理信息系统的必要性的同时，阐述了区分模型综合和图像综合在新环境下的实用意义，并总结了欧洲和北美地区在自动化综合研究方面所作的主要努力。通过分析现阶段综合方法和编程语言的特点，指出了现有计算机综合系统由于缺乏专家知识而存在的缺陷和局限性，并相应地介绍和讨论了知识获取和表达的几种实用方法。最后，列举了开发未来高智能自动化综合系统应当注意的问题和必须具备的条件。     

城市地理信息系统的发展

回顾了城市地理信息系统的历史，分析了城市地理信息系统的现状和问题，指出了城市地理信息系统的发展方向。