Data structures for three-dimensional spatial information systems in geology     

CHRISTOPHER B. JONES 《International journal of geographical information science》2013,27(1):15-31

Abstract

The accumulation of geological information in digital form, due to modern exploration methods, has introduced the possibility of applying geographical information system technology to the field of geology. To achieve the benefits in information management and in data analysis and interpretation, however, it will be necessary to develop spatial models and associated data structures which are specifically designed for working in three dimensions. Some progress in this direction has already been demonstrated, with the application of octree spatial subdivision techniques to the storage of uniform volume elements representing mineral properties. By imposing octree tessellations on more precisely-defined geometric data, such as triangulated surfaces and polygon line segments, it may now be possible to combine efficient spatial addressing with topologically-coded boundary representations of geological strata. The development of storage schemes capable of representing such geological boundary models at different scales poses a particular problem, a possible solution to which may be by means of hierarchical classification of the vertices of triangulated surfaces according to shape contribution.  相似文献   

基于LabVIEW的预应力孔道压浆质量检测仪的软件设计     

余涛  朱自强  蒋奇云  鲁光银  曾智力 《地球物理学进展》2013,28(3)

本文提出了一种预应力孔道压浆质量检测仪的硬件方案,在此基础上介绍了基于LabVIEW的仪器软件设计,重点讨论了软件实现的关键技术,实现了参数设置,多通道超声信号采集,文件管理等功能.软件界面友好,操作简单,适应仪器的野外工作,且升级维护方便.  相似文献   

Potential use of dissolved cyanobacterial DNA for monitoring toxic Microcystis cyanobacteria in filtered water     

《Physics and Chemistry of the Earth》2013

Toxic and non-toxic Microcystis sp. are morphologically indistinguishable cyanobacteria that are increasingly posing health problems in fresh water systems by producing odours and/or toxins. Toxic Microcystis sp. produces toxicologically stable water soluble toxic compounds called microcystins (MCs) that have been associated with cases of aquatic life and wildlife poisoning and kills including some cases of human illnesses/deaths around the world. Thus, the need for rapid detection of toxic Microcystis sp. in surface water is imperatively a necessity for early mitigation purposes. Genomic DNA from potentially toxic Microcystis sp. comprises of ten microcystin synthetase (mcy) genes of which six major ones are directly involved in MCs biosynthesis. In Polymerase Chain Reaction (PCR) methodsmcy genes can be amplified from intracellular/extracellular genomic DNA using PCR primers. However, little is known about the limitations of sourcing genomic DNA templates from extracellular DNA dissolved in water. In this work, filtered water (0.45 μM) from a Microcystis infested Dam (South Africa) was re-filtered on 0.22 μM syringe filters followed by genomic DNA isolation and purification from micro-filtrates (9 mL). Six major mcy genes (mcyABCDEG) from the isolated DNA were amplified using newly designed as well as existing primers identified from literature. PCR products were separated by gel electrophoresis and visualized after staining with ethidium bromide. The limitation of using dissolved DNA for amplification of mcy genes was qualitatively studied by establishing the relationship between input DNA concentrations (10.0–0.001 ng/μL) and the formation of respective PCR products. The amplification of mcyA gene using new primers with as little as 0.001 ng/μL of DNA was possible. Other mcy gene sensitivities reached 0.1 ng/μL DNA dilution limits. These results demonstrated that with appropriately optimized PCR conditions the method can provide accurate cost-effective tools for rapid detection of toxic Microcystis sp. in water giving early information for water quality monitoring against MC producing cyanobacteria.  相似文献   

Impacts of urbanisation on hydrological and water quality dynamics,and urban water management: a review     

Scott J. McGrane 《水文科学杂志》2013,58(13):2295-2311

ABSTRACT

As urban space continues to expand to accommodate a growing global population, there remains a real need to quantify and qualify the impacts of urban space on natural processes. The expansion of global urban areas has resulted in marked alterations to natural processes, environmental quality and natural resource consumption. The urban landscape influences infiltration and evapotranspiration, complicating our capacity to quantify their dynamics across a heterogeneous landscape at contrasting scales. Impervious surfaces exacerbate runoff processes, whereas runoff from pervious areas remains uncertain owing to variable infiltration dynamics. Increasingly, the link between the natural hydrological cycle and engineered water cycle has been made, realising the contributions from leaky infrastructure to recharge and runoff rates. Urban landscapes are host to a suite of contaminants that impact on water quality, where novel contaminants continue to pose new challenges to monitoring and treatment regimes. This review seeks to assess the major advances and remaining challenges that remain within the growing field of urban hydrology.