低空遥感在违法建筑快速监测中的应用

介绍了低空遥感平台及其数据特点,研究了其检测城市变化的方法,实现了对违法建筑的快速监测。     

三维城市地质空间数据库数据组织及模式设计

如何建立高效的数据组织以及存储模式是三维城市地质数据库必需要解决的两大基础性问题。本文通过引入基于地学属性的三维矢量数据组织方法以及基于类八叉树的真三维体数据组织方法,解决了传统海量三维空间数据无法在数据库中高效组织和访问的问题,从而在真正意义上实现了三维城市地质空间数据的数据库组织;并在此基础之上,针对城市地质空间数据的特点,提出了元数据驱动的数据存储模式,有效地增强了三维城市地质空间数据库的可扩展性和灵活性。     

利用Geoway ImageStation和SQL Server进行正射影像生产的若干问题思考

首先介绍Geoway ImageStation和SQL Server相结合的新型正射影像生产模式的产生背景,通过对全国第二次土地调查底图生产项目中正射影像制作过程中遇到的若干问题进行阐述,以及对正射影像产品质量进行分析,说明此种生产模式的优势和可行性.     

海洋声速剖面的自动聚类研究

以海区30'网格方区多年月平均统计的声速剖面作为原始数据集,提取声速剖面的表层、主跃层和深海等温层分层结构特征,把我国近海及其邻近海域预分为Ⅰ,Ⅱ和Ⅲ类区。对Ⅱ,Ⅲ类区声速剖面,应用有序样本聚类算法分别进行表层分离。根据各类区的表层声速剖面数据,通过归一化处理和Akima差值采样得到梯度剖面,建立起按月归一化后的声速剖面分层梯度样本集,并应用系统聚类法和SOFM神经网络方法分别进行聚类分析,再根据分类结果并结合各类型海区的声学特点,得到各类型海区声速剖面的典型类型。通过对大量历史数据的分析结果表明,该方法为自动分类海洋声速剖面提供了一条有效路径,弥补了长期以来海洋声速剖面主要依靠人工分类的不足。     

Community structure of bathyal decapod crustaceans off South-Eastern Sardinian deep-waters (Central-Western Mediterranean)

Community structure and faunal composition of bathyal decapod crustaceans off South-Eastern Sardinian deep-waters (Central-Western Mediterranean) were investigated. Samples were collected during 32 hauls between 793 and 1598 m in depth over the 2003–2007 period. A total of 1900 decapod specimens belonging to 23 species were collected. Multivariate analysis revealed the occurrence of three faunistic assemblages related to depth: (i) an upper slope community at depths of 793–1002 m; (ii) a middle slope community at depths of 1007–1212 m and (iii) a lower slope community at depths greater 1420 m. In the upper and middle slopes the benthic ( Polycheles typhlops ) and epibenthic–endobenthic feeders (mainly Aristeus antennatus and Geryon longipes ), which eat infaunal prey, were dominant, followed by the macroplankton–epibenthic feeders such as Acanthephyra eximia and Plesionika acanthonotus . In the deepest stratum, the most remarkable feature was the prevalence of macroplankton–epibenthic feeders ( A. eximia and P. acanthonotus ). A small percentage of the benthic deep-sea lobster Polycheles sculptus was also present. The biomass presented higher values in the middle slope and declined strongly in the lower slope. There was no general pattern of mean individual weight/size versus depth among decapods, and the changes seemed to be species-specific with different trends.     

Estimating copepods' abundance with paired nets: Implications of mesh size for population studies

Three representative copepods occurring in the southern Patagonian shelf, i.e., Calanus australis, Drepanopus forcipatus and Oithona helgolandica were sampled by the first time with paired nets of 66 and 150 µm mesh size. The stage-specific estimates of abundance of their populations were statistically analyzed to assess differences in the catchability by both plankton nets. Differences between nets were significant only for smaller developmental stages and species, with higher catchabilities by the 66 µm net, while no differences were detected for most of the stages of the medium and large size species. A significant effect of the spatial distribution on the estimates of abundance was detected for the majority of the species and stages but the interaction between mesh size and spatial distribution was not significant. This means that differences between both nets were maintained across the latitudinal gradient. Our results strongly suggest the convenience of using the 66 µm plankton net to estimate the abundance of the three copepods' populations. Furthermore, we propose a correction factor to adjust past estimates of abundances from 150 µm mesh collections.     

兰州城区稳定能量及其与空气污染的关系

从能量学的观点出发，提出了描述地面至特定高度大气层结构稳定度的参数－稳定能量，并给出了具体计算方法。根据1988－1992年兰州气象站逐日08：00（北京时，下同）的探空资料，计算了300－1000m每隔50m共15层的稳定能量。利用同期兰州市环境监测站自动监测系统监测的兰州城区3种主要空气污染物二氧化硫、一氧化碳和氮氧化物（SO2、CO、NOX）的日平均浓度资料，计算了地面气象要素、低空气象参数、低空风和稳定能量等气象因子与SO2、CO、NOX之间的相关。结果表明：（1）用稳定能量来描述低层大气的稳定性更为合理一些；（2）在诸多气象因子中，稳定能量与SO2、CO、NOX浓度之间的相关性最显著；（3）稳定能量的年变化规律与空气污染浓度的年变化规律基本一致；（4）逐月看，各层稳定能量与SO2浓度之间均为正相关，除7月份以外，大多数层次均通过了α＝0．01显著性水平的相关性检验。     

Collective control of spacecraft swarms for space exploration

Swarms are characterized in nature by a dynamic behaviour which is quite appealing for researchers involved in numerous fields of study, like robotics, computer science, pure mathematics and space sciences. Global group organization acquired in absence of centralized control is the feature of natural swarms which is most interesting to reproduce. This study proposes to make use of some evolutionary robotics findings in order to obtain the autonomous group organization in the framework of a deeper knowledge of the astrodynamics. The main task which will be accomplished is the implementation of the control laws for the single satellite. A careful tuning of the parameters at member level is necessary in order to gain an autonomously evolving global behaviour in a number of space missions of immediate interest. In remote sensing missions, for example, trains of a small number of satellites are already orbiting and integrating their collected data: in near future entire swarms of agents could accomplish this task, and should be controlled in order to acquire and maintain the desired leader-follower configuration. Another example can be seen in deep space exploration of unknown celestial bodies, where the migration of the entire swarm from a reference orbit to a (previously unknown) targeted one is an issue; the same group migration is of interest in Earth orbit, when transferring from parking to operational orbit. Finally, self-assembly of rigid-like virtual structures is also simulated. This paper shows that all these cases are autonomously performed by the swarm by correctly implementing four simple rules at individual level, which assess the primal needs for any satellite: avoid collision, remain grouped, align to the neighbor, reach a goal.     

Influence of sedimentary setting on the use of magnetic susceptibility: examples from the Devonian of Belgium

Bulk magnetic susceptibility measurements on sedimentological samples from all geological periods have been used widely in the last two decades for correlations and as a proxy for sea‐level variations. This paper explores the link between magnetic susceptibility, depositional setting and environmental parameters. These environmental parameters include distal–proximal transects, microfacies successions and fourth‐order trends on different carbonate platform types (platform, ramp, carbonate mound or atoll) during different Devonian stages (Eifelian, Givetian and Frasnian). Average magnetic susceptibility values over a distal–proximal‐trending facies succession vary markedly with depositional setting. On carbonate platforms, average magnetic susceptibility generally increases towards the top of shallowing‐upward sequences. On a distal–proximal transect, average magnetic susceptibility is intermediate for the deepest facies, decreases for the reef belts and increases to a maximum in the back‐reef zone. In ramps and atolls, magnetic susceptibility trends clearly differ; average magnetic susceptibility generally decreases towards the top of shallowing‐upward sequences and is highest in the deepest facies. The strong relationship between magnetic susceptibility, facies and sequences implies a strong environmental influence. However, the different responses in the different platform types suggest that sea‐level changes leading to variation in detrital input is not the only parameter controlling average magnetic susceptibility values. Other primary or secondary processes also probably influenced magnetic mineral distribution. Primary processes such as carbonate production and water agitation during deposition are probably key factors. When carbonate production is high, the proportion of magnetic minerals is diluted and the magnetic susceptibility signal decreases. High water agitation during deposition will also selectively remove magnetic minerals and will lead to low average magnetic susceptibility values. These parameters explain the lowest values observed on the reef platform, inner ramp and atoll crown, which are all in areas characterized by higher carbonate production and greater water agitation during deposition. The lowest values observed in the lagoon inside the atoll crown can be related to detrital isolation by the atoll crown. However, other parameters such as biogenic magnetite production or diagenesis can also influence the magnetic signal. Diagenesis can change magnetism by creating or destroying magnetic minerals. However, the influence of diagenesis probably is linked strongly to the primary facies (permeability, amount of clay or organic matter) and probably enhanced the primary signal. The complexity of the signal gives rise to correlation problems between different depositional settings. Thus, while magnetic susceptibility has the potential to be an important correlation tool, the results of this investigation indicate that it cannot be used without consideration of sedimentary processes and depositional environments and without strong biostratigraphical control.     

基于OrthoVista的数字正射影像快速成图的方法研究

以武汉市东湖国家自主创新示范区的正射影像生产工程为例,阐述利用德国InPhO公司的O rthoV ista软件制作正射影像图的方法,并结合生产流程中的部分环节,提出了若干快速成图的方法。