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21.
22.
A GIS-implemented, deterministic approach for the automated spatial evaluation of geometrical and kinematical properties of
rock slope terrains is presented. Based on spatially distributed directional information on planar geological fabrics and
DEM-derived topographic attribute data, the internal geometry of rock slopes can be characterized on a grid cell basis. For
such computations, different approaches for the analysis and regionalization of available structural directional information
applicable in specific tectonic settings are demonstrated and implemented in a GIS environment. Simple kinematical testing
procedures based on feasibility criteria can be conducted on a pixel basis to determine which failure mechanisms are likely
to occur at particular terrain locations. In combination with hydraulic and strength data on geological discontinuities, scenario-based
rock slope stability evaluations can be performed. For conceptual investigations on rock slope failure processes, a GIS-based
specification tool for a 2-D distinct element code (UDEC) was designed to operate with the GIS-encoded spatially distributed
rock slope data. The concepts of the proposed methodology for rock slope hazard assessments are demonstrated at three different
test sites in Germany. 相似文献
23.
24.
Over the past decade, the electric vehicle (EV) industry has experienced unprecedented growth and diversification, resulting in a complex ecosystem. To effectively manage this multifaceted field, we present an EV-centric knowledge graph (EVKG) as a comprehensive, cross-domain, extensible, and open geospatial knowledge management system. The EVKG encapsulates essential EV-related knowledge, including EV adoption, EV supply equipment, and electricity transmission network, to support decision-making related to EV technology development, infrastructure planning, and policy-making by providing timely and accurate information and analysis. To enrich and contextualize the EVKG, we integrate the developed EV-relevant ontology modules from existing well-known knowledge graphs and ontologies. This integration enables interoperability with other knowledge graphs in the Linked Data Open Cloud, enhancing the EVKG's value as a knowledge hub for EV decision-making. Using six competency questions, we demonstrate how the EVKG can be used to answer various types of EV-related questions, providing critical insights into the EV ecosystem. Our EVKG provides an efficient and effective approach for managing the complex and diverse EV industry. By consolidating critical EV-related knowledge into a single, easily accessible resource, the EVKG supports decision-makers in making informed choices about EV technology development, infrastructure planning, and policy-making. As a flexible and extensible platform, the EVKG is capable of accommodating a wide range of data sources, enabling it to evolve alongside the rapidly changing EV landscape. 相似文献
25.
In an elementary approach every geometrical height difference between the staff points of a levelling line should have a corresponding
average g value for the determination of potential difference in the Earth’s gravity field. In practice this condition requires as
many gravity data as the number of staff points if linear variation of g is assumed between them. Because of the expensive fieldwork, the necessary data should be supplied from different sources.
This study proposes an alternative solution, which is proved at a test bed located in the Mecsek Mountains, Southwest Hungary,
where a detailed gravity survey, as dense as the staff point density (~1 point/34 m), is available along a 4.3-km-long levelling
line. In the first part of the paper the effect of point density of gravity data on the accuracy of potential difference is
investigated. The average g value is simply derived from two neighbouring g measurements along the levelling line, which are incrementally decimated in the consecutive turns of processing. The results
show that the error of the potential difference between the endpoints of the line exceeds 0.1 mm in terms of length unit if
the sampling distance is greater than 2 km. Thereafter, a suitable method for the densification of the decimated g measurements is provided. It is based on forward gravity modelling utilising a high-resolution digital terrain model, the
normal gravity and the complete Bouguer anomalies. The test shows that the error is only in the order of 10−3mm even if the sampling distance of g measurements is 4 km. As a component of the error sources of levelling, the ambiguity of the levelled height difference which
is the Euclidean distance between the inclined equipotential surfaces is also investigated. Although its effect accumulated
along the test line is almost zero, it reaches 0.15 mm in a 1-km-long intermediate section of the line. 相似文献
26.
Many regions around the world require improved gravimetric data bases to support very accurate geoid modeling for the modernization
of height systems using GPS. We present a simple yet effective method to assess gravity data requirements, particularly the
necessary resolution, for a desired precision in geoid computation. The approach is based on simulating high-resolution gravimetry
using a topography-correlated model that is adjusted to be consistent with an existing network of gravity data. Analysis of
these adjusted, simulated data through Stokes’s integral indicates where existing gravity data must be supplemented by new
surveys in order to achieve an acceptable level of omission error in the geoid undulation. The simulated model can equally
be used to analyze commission error, as well as model error and data inconsistencies to a limited extent. The proposed method
is applied to South Korea and shows clearly where existing gravity data are too scarce for precise geoid computation. 相似文献
27.
Reshu Agarwal Rakesh Gupta J. K. Garg 《Journal of the Indian Society of Remote Sensing》2009,37(3):473-481
A three-step hierarchical Semi Automated Empirical Methane Emission Model (SEMEM) has been used to estimate methane emission
from wetlands and waterlogged areas in India using Moderate Resolution Imagine Spectroradiometer (MODIS) sensor data onboard
Terra satellite. Wetland Surface Temperature (WST), methane emission fluxes and wetland extent have been incorporated as parameters
in order to model the methane emission. Analysis of monthly MODIS data covering the whole of India from November 2004 to April
2006 was carried out and monthly methane emissions have been estimated. Interpolation techniques were adopted to fill the
data gaps due to cloudy conditions during the monsoon period. AutoRegressive Integrated Moving Average (ARIMA) model has been
fitted to estimate the emitted methane for the months of May 2006 to August 2006 using SPSS software. 相似文献
28.
29.
Kamlesh P. Lulla Michael R. Helfert David L. Amsbury Victor S. Whitehead Cynthia A. Evans M. Justin Wilkinson 《国际地球制图》2013,28(1):69-80
Abstract Multi‐temporal ERS‐1 SAR data acquired over a large agricultural region in West Bengal was used to classify kharif crops like rice, jute and sugarcane. Rice crop grown under lowland management practice showed a temporal characteristic. The dynamic range of backscatter was highest for this crop in temporal SAR data. This was used to classify rice using temporal SAR data. Such temporal character was not observed for the other study crops, which may be due to the difference in cultivation practice and crop calendar. Significant increase in backscatter from the ploughed fields was used to derive information on onset and duration of land preparations. Synergistic use of optical remote sensing data and SAR data increased the separability of rice crop from homesteads and permanent vegetation classes. 相似文献
30.
Michael A. O'Neal 《国际地球制图》2013,28(4):315-325
Climatic interpretations of recent glacier fluctuations rely on ice-extent chronologies developed from lichenometric ages of Holocene landforms. However, lichenometry requires time- and resource-consuming field surveys, which limit our understanding of glacier chronologies, especially in remote locations. This study presents a rapid, coarse, a priori approach to predicting new field sites where lichenometry can be applied. Geologic, geographic, climatic, and landcover data were used in spatial and supervised classification analyses to identify areas in the Cascade Range of Washington and northern Oregon with similar environmental conditions to those where lichenometric dating techniques had previously been applied. These results focus the attention of researchers to only 1100 km2, or 3%, of the broader Cascade Range study area. Though this study concentrates on the utility of lichenometry for dating recent glacier activity in the Cascade Range, the screening method presented is easily translatable to a variety of geomorphic and environmental applications. 相似文献