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911.
912.
小波变换理论在炸药装药安全性检验中的应用 总被引:1,自引:0,他引:1
工业CT探测炸药时,存在的严重噪声使得信号难以识别,严重影响了炸药探测的可靠度和精确度.为提高工业CT探测炸药的信噪比和可靠性,利用小波变换的方法降低信号噪声以实现有效的炸药探测.结果显示,小波变换可以实际地进行工业CT探测炸药得到的信号的分析,能有效地抑制噪声和提高信噪比,并且利用小波变换可以检测出药柱的裂纹以及裂纹的位置. 相似文献
913.
锚杆支护巷道安全监测技术 总被引:11,自引:3,他引:8
锚杆支护巷道顶板冒落具有突发性和冒落面积大的特点 ,安全监测非常必要。笔者介绍了国内近年来最新研制的CM— 2 0 0型测力锚杆、GYS— 30 0型锚杆 (索 )测力计、LBY— 3型顶板离层指示仪、ZW— 4型遥测多点位移计等监测仪器 ;提出锚杆支护巷道动态信息施工方法 :监测施工、监测信息反馈、检验和修正设计 ,循环往复 ,以达到最佳施工效果。 相似文献
914.
Van Der Perk M Burema J Vandenhove H Goor F Timofeyev S 《Journal of environmental management》2004,72(4):770-240
A Monte Carlo analysis of two sequential GIS-embedded submodels, which evaluate the economic feasibility of short rotation coppice (SRC) production and energy conversion in areas contaminated by Chernobyl-derived (137)Cs, was performed to allow for variability of environmental conditions that was not contained in the spatial model inputs. The results from this analysis were compared to the results from the deterministic model presented in part I of this paper. It was concluded that, although the variability in the model results due to within-gridcell variability of the model inputs was considerable, the prediction of the areas where SRC and energy conversion is potentially profitable was robust. If the additional variability in the model input that is not contained in the input maps is also taken into account, the SRC production and energy conversion appears to be potentially profitable at more locations for both the small scale and large scale production scenarios than the model predicted using the deterministic model. 相似文献
915.
基于“3S”技术构建农业灾害监测信息系统 总被引:25,自引:1,他引:24
本文从介绍遥感、地理信息系统、全球定位系统在建设农业灾害监测信息系统中的特点和优势出发,阐述了“3S”技术在农业灾害监测信息系统中的作用。在此基础上,提出了基于“3S”技术建设农业灾害监测信息系统的构想。 相似文献
916.
Factors affecting private forest landowner interest in ecosystem management: linking spatial and survey data 总被引:1,自引:0,他引:1
Jacobson MG 《Environmental management》2002,30(4):577-583
Many factors influence forest landowner management decisions. This study examines landowner decisions regarding participation
in ecosystem management activities, such as a landscape corridor cutting across their private lands. Landscape corridors are
recognized worldwide as an important tool in biodiversity conservation. For ecosystem management activities to occur in areas
dominated by a multitude of small private forest landholdings, landowner participation and cooperation is necessary. Data
from a survey of landowners combined with an analysis of their land's spatial attributes is used to assess their interest
in ecosystem management. Results suggest that spatial attributes are not good predictors of an owner's interest in ecosystem
management. Other factors such as attitudes and opinions about the environment are more effective in explaining landowner
interest. The results have implications for any land manager using GIS data and implementing ecosystem management activities
on private forestland. 相似文献
917.
Environmental surveys yield three principal products: maps, a set of data tables, and a textual report. The relationships between these three elements, however, are often cumbersome to present, making full use of all the information in an integrated and systematic sense difficult. The published paper report is only a partial solution. Modern developments in computing, particularly in cartography, GIS, and hypertext, mean that it is increasingly possible to conceive of an easier and more interactive approach to the presentation of such survey results. Here, we present such an approach which links map and tabular datasets arising from a vegetation survey, allowing users ready access to a complex dataset using dynamic mapping techniques. Multimedia datasets equipped with software like this provide an exciting means of quick and easy visual data exploration and comparison. These techniques are gaining popularity across the sciences as scientists and decision-makers are presented with increasing amounts of diverse digital data. We believe that the software environment actively encourages users to make complex interrogations of the survey information, providing a new vehicle for the reader of an environmental survey report. 相似文献
918.
Land-use suitability analysis in the United States: historical development and promising technological achievements 总被引:19,自引:1,他引:18
Various methods of spatial analysis are commonly used in land-use plans and site selection studies. A historical overview
and discussion of contemporary developments of land-use suitability analysis are presented. The paper begins with an exploration
into the early 20th century with the infancy of documented applications of the technique. The article then travels through
the 20th century, documenting significant milestones. Concluding with present explorations of advanced technologies such as
neural computing and evolutionary programming, this work is meant to serve as a foundation for literature review and a premise
for the exploration of new advancements as we enter into the 21st century. 相似文献
919.
信息融合技术在锅炉故障诊断中的应用 总被引:1,自引:0,他引:1
为满足锅炉故障诊断的要求,用信息融合技术,提出了具有数据挖掘功能的锅炉故障诊断系统的一般模型。在对锅炉故障诊断中的信息进行分类的基础上,详细阐述了模型中各功能模块的作用以及它们之间的层次关系,并提出了模型中关键技术的实现方法。实例分析表明,信息融合技术用于锅炉故障诊断对提高诊断的可靠性和准确性有重要作用。 相似文献
920.
基于XML语言的信息隐藏方法 总被引:5,自引:2,他引:5
XML作为网络中的信息交换格式,一出现便得到了广泛的应用和支持。XML不是一种普通的文本语言,它用于置标电子文档,是一种使其数据具有结构化的置标语言。利用XML的这一特性,可以将秘密的信息隐藏到XML文本中。笔者通过研究XML语言的基本特性和XML语言在网络中的应用,提出了几种基于XML语言的信息隐藏方法,这种方法的理论基础简单,同时也便于在实际中应用。 相似文献