基于PC机上的桌面图形图像处理软件在遥感调查中的应用潜能

本文以南沙群岛岛、礁、滩、沙分布现状遥感调查为例,介绍基于PC机上的桌面图形、图像处理软件在遥感图像处理、解译和制图中的应用及其优越性。实践证明,桌面软件功能强大,具有操作方便、易于普及的特点,并能够实现可视化的计算机交互式图像解译和全数字化的计算机遥感制图。     

Morphotectonic evidence from lateral propagation of an active frontal fold; Pakuashan anticline, foothills of Taiwan

The Pakuashan anticline is uniquely suited for study of the forward and lateral growth of fault-related folds. The Pakuashan ridge development arises from the late Quaternary uplift of the most external thrust zone of the western foothills of Taiwan. From Kaoshiung to Taichung, recent and active westward thrusting occurs at the front of the foothills. The Pakuashan anticline, trending N 150°E in the northern part to N 000° in the southern part, has been active throughout the Quaternary period. This activity is marked by geological structures, tectonic geomorphology and seismicity. A multisource and multiscale approach to study of the continental collision setting has been undertaken to combine tectonics, sedimentology and geomorphology. Studies of fracture patterns allow identification of two main features of stress orientations: a WNW/ESE compression direction, and E–W and N–S extension directions. Quantitative geomorphic parameters have been used to define the morphotectonic evolution and to infer tectonic style along the mountain front. Geomorphic evidence provides significant information on the processes that govern lateral propagation of an active anticline. Quaternary terraces are uplifted, tilted and folded over the Pakuashan ridge. Drainage systems in areas of active compression give information on the thrust zone structures and their development. Steep drainage and high local relief indicate that the Pakuashan anticline forms a well-defined zone of high uplift, especially in the southern part. The two main controls on drainage in that area are rock strength in the hanging wall and propagation of the deformation towards the south.     

分析测试质量监控软件的开发与应用

编制了计算机统计计算密码抽查的合格率和插入标准样品分析结果累计统计的精密度和准确度的程序,从而大大减少了管理人员的劳动强度,提高了工作效率。实践证明,应用所编程序统计的合格率、准确度及精密度准确可靠,操作简单,方便。     

The unusual cyclicity of the Triassic (Carnian) Bleiberg facies of the Wetterstein Formation (Drau Range,Austria)

The carbonate platform of the upper Wetterstein Formation (Cordevol) of the Drau Range (Austria) shows a distinct facies differentiation which depends on the palaeotopography. Although most areas of the platform were permanently flooded, a periodically emergent palaeotopographic high (Bleiberg facies) occurred near to the centre of the platform. The resulting cyclic sequences are composed of subtidal and intertidal to supratidal carbonates and emersion horizons. Typical shallowing upward cycles occur, as well as deepening upward, symmetrical and incomplete cycles. These types of cycles, with long-term emersion phases, can be explained by eustatic sea-level oscillations. It can be shown, due to an excellent lithostratigraphy based on distinct emersion horizons, that the cycle-type varies along a marker bed while the vertical distance between the emersion horizons is retained. Therefore the cycles cannot be explained by eustatic sea-level oscillations alone; local events which produce a local relief are necessary.A compiled profile of the Bleiberg facies is simulated with the help of a one-dimensional, parametric computer model. The quantification of some parameters which result from this simulation is used to verify and quantify the effects of relief on sedimentation.     

Predicting air temperature simultaneously for multiple locations in an urban environment: A bottom up approach

Cities are characterized by high heterogeneity that results in varied microclimate effects. The current study introduces a new bottom–up approach linking the urban Canyon Air Temperature (CAT) model with spatially distributed inputs extracted from a GIS data-base and remote sensing products to predict intra-urban temperature variability simultaneously for multiple locations in an urban environment. To provide proof of concept, the model was applied for the city of Bat-Yam, Israel. Simulation shows a maximum nighttime urban heat island (UHI) intensity of 2–2.25 °C, relative to a rural reference point, during both summer and winter, with significant spatial variability related to the height-to-width ratio of urban street canyons and to the surface land cover. The CAT simulation also highlighted the important influence of the local wind regime on the development and persistence of the nocturnal UHI. We conclude that linking CAT to a GIS data-base supports simulations at the city scale that reflect the local intra-urban variability. The model can be used to investigate both macro and micro scale spatio-temporal characteristics of the UHI in various urban development scenarios, which may be applied to generate appropriate geographically-explicit mitigation and adaptation measures.     

国家防震减灾指挥中心的构成

介绍了防震减灾指挥中心作为领导和专家共同迅速有效处置地震应急事件的工作平台,该中心是国务院抗震救灾指挥的主要工作场所。防震减灾指挥中心包括指挥中心机房、指挥大厅和辅助工作区三部分。指挥中心建设是一项复杂的系统工程建设项目,包括了计算机系统、网络、通讯、声像、供电、空调、投影显示、GIS技术应用、数据库、软件开发、机房建设等。可对抗震救灾工作快速作出科学决策。     

离子束抛光工艺中驻留时间的分步消去算法

在离子束抛光工艺中,驻留时间的求解是很关键的。求解驻留时间是利用离子束加工函数和驻留时间的卷积等于镜面去除量的关系,而离子束抛光的过程就是一个执行解卷积的过程。受此启发,采用一种分步消去算法解矩阵的卷积运算。这种新算法占用计算机资源少,运算速度快,同时可以根据预先设定的加工精度算得满足要求的驻留时间函数。对这种新算法进行仿真分析,采用3种不同的消去顺序分步加工,得到了理想的仿真结果,PV值由抛光前的363.721 nm分别减小到6.136 nm、33.347 nm、3.875 nm,抛光后的镜面精度提高了很多。     

Asteroid identification at discovery

We present a novel method for the search of linkages among astrometric observations of asteroids, that is, tentative identifications among asteroids observed. Having two different master sets of asteroid observations each containing a number of separate subsets, we define a linkage as a pair of subsets residing in separate master sets that can be tied together with an orbit for given observational errors. To find linkages among a wealth of observations we use an efficient stepwise filtering approach. First, we start with what we call phase-space address comparison. The first step substantially reduces the initially huge amount of pairs by requiring that pairs to be subjected to further analysis have similar geocentric spherical coordinates at common epochs (for example, at three epochs). Second, we search for orbits for each of the selected pairs of subsets. Succeeding in the effort proves that a linkage exists. If there are contradictions among linkages found—for example, a single subset being linked to several mutually exclusive subsets—additional new or archive observations are usually needed to discard erroneous linkages. The new method is built on six-dimensional statistical orbital inversion (Ranging), and is therefore particularly suitable for analyzing objects with the shortest observational arcs, that is, newly discovered asteroids (and comets). Results from extensive and successful tests on simulated survey observations are presented and discussed. Theoretical and empirical scaling results show that the method is applicable to future large-scale surveys that will increase the rate of asteroid discovery by at least two orders of magnitude. The successful linking of faint single-night observation sets obtained with the Very Large Telescope are briefly reviewed.     

Light scattering by media composed of semitransparent particles of different shapes in ray optics approximation: consequences for spectroscopy, photometry, and polarimetry of planetary regoliths

Computer simulations of light scattering by particulate surfaces and single particles forming these surfaces are presented. The ray optics approximation is used. Three types of particles are studied: spheres, cubes, and very irregular particles that are generated with an auxiliary random Gaussian field. The surfaces of the particles are represented as an arrangement of triangular facets. For the Monte Carlo ray tracing 10⁶−10⁷ rays were used. The ray tracing verifies Shkuratov et al.'s (Icarus 137 (1999) 235-246) spectral albedo model for powder-like media. We derive a useful relationship between the hemispheric albedo, A_int, and the bi-directional reflectance, R, at phase angle 30°: logR(30°)=1.088logA_int. This relationship provides a way to estimate bi-directional reflectance spectra from laboratory spectra measured with an integrating sphere for surfaces composed of particles of irregular shapes. We study also phase angle curves of the nonzero scattering matrix elements, F₁₁, −F₁₂/F₁₁, F₂₂/F₁₁, F₃₃/F₁₁, F₃₄/F₁₁, F₄₄/F₁₁, for single particles and media thereof. Randomly shaped particles show smoother phase angle behavior than particles with regular shapes that display distinct features. For media consisting of spheres the glory and primary rainbow both are prominent even in the case of conservative (nonabsorbing) scattering. On the other hand, such media clearly exhibit the depolarization effect, showing a significant role of multiple scattering between particles. For media composed of semitransparent cubes the retroreflector spike and a very deep negative polarization branch at small phase angles are observed. We demonstrate that, in the geometric optics approximation, neither a medium of spherical particles nor one of cubic particles is appropriate for modeling light scattering behavior of regolith-like surfaces.     

Search for shadowing of primary cosmic radiation by the moon at TeV energies

The antimatter research through the earth moon ion spectrometer (ARTEMIS) experiment is described in terms of searching for the moon's shadow in the primary cosmic radiation at TeV energies. Observations were made using the Whipple 10 m Imaging Atmospheric erenkov Telescope, in conjunction with a special optical filter to suppress unwanted moonlight. Monte Carlo simulations were used to predict that the magnitude of shadowing based on a pure proton beam would be 1% of the cosmic ray background. Observations and event classification are discussed, and results of a search for shadowing based on both protons and antiprotons are presented. Atmospheric fluctuations giving rise to non-statistical event rates constituted a limiting factor to the sensitivity of the shadow search as they rivaled or exceeded statistical errors. It is demonstrated that the experiment does not have sufficient sensitivity to moon shadowing which would allow a search for an antimatter component in the primary cosmic ray flux at the percent level. Possible future improvements of the technique are discussed.