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81.
Spatial statistical analysis and geographic information systems   总被引:25,自引:0,他引:25  
In this paper, we discuss a number of general issues that pertain to the interface between GIS and spatial analysis. In particular, we focus on the various paradigms for spatial data analysis that follow from the existence of this interface. We outline a series of questions that need to be confronted in the analysis of spatial data, and the extent to which a GIS can facilitate their resolution. We also review a number of exploratory and confirmatory techniques that we feel should form the core of a spatial analysis module for a GIS.  相似文献   
82.
83.
Heavy metal escapement associated with ore trucks is known to occur along the DeLong Mountain Regional Transportation System (DMTS) haul road corridor in Cape Krusenstern National Monument, northwest Alaska. Heavy metal concentrations in Hylocomium splendens moss (n = 226) were used in geostatistical models to predict the extent and pattern of atmospheric deposition of Cd and Pb on Monument lands. A stratified grid-based sample design was used with more intensive sampling near mine-related activity areas. Spatial predictions were used to produce maps of concentration patterns, and to estimate the total area in 10 moss concentration categories. Heavy metal levels in moss were highest immediately adjacent to the DMTS haul road (Cd > 24 mg/kg dw; Pb > 900 mg/kg dw). Spatial regression analyses indicated that heavy metal deposition decreased with the log of distance from the DMTS haul road and the DMTS port site. Analysis of subsurface soil suggested that observed patterns of heavy metal deposition reflected in moss were not attributable to subsurface lithology at the sample points. Further, moss Pb concentrations throughout the northern half of the study area were high relative to concentrations previously reported from other Arctic Alaska sites. Collectively, these findings indicate the presence of mine-related heavy metal deposition throughout the northern portion of Cape Krusenstern National Monument. Geospatial analyses suggest that the Pb depositional area extends 25 km north of the haul road to the Kisimilot/Iyikrok hills, and possibly beyond. More study is needed to determine whether higher moss heavy metal concentrations in the northernmost portion of the study area reflect deposition from mining-related activities, weathering from mineralized Pb/Zn outcrops in the broader region, or a combination of the two. South of the DMTS haul road, airborne deposition appears to be constrained by the Tahinichok Mountains. Heavy metal levels continue to diminish south of the mountains, reaching a minimum in the southernmost portion of the study area near the Igichuk Hills (45 km from the haul road). The influence of the mine site was not studied.  相似文献   
84.
Sofronova  E. D.  Lipin  V. A.  Sustavova  T. A. 《Fibre Chemistry》2022,53(5):342-345
Fibre Chemistry - Under modern conditions the creation of materials for sanitary hygiene and medical products based on cellulose is of paramount importance. Development and improvement in this area...  相似文献   
85.
Theoretical Foundations of Chemical Engineering - The paper presents a study of the process of the isolation of styrene-butadiene rubber from latex with the method of mathematical planning for a...  相似文献   
86.
Makarov  R. I.  Khorosheva  E. R. 《Glass and Ceramics》2022,78(9-10):350-352
Glass and Ceramics - Selective quality control of manufactured multilayer windshields was conducted. Deviations of curved products from a specified shape were brought to light. Linear regression...  相似文献   
87.
Glass and Ceramics - A catalyst was developed in the form of a composite based on a zeolite matrix modified with titanium nanoparticles based on zeolite raw materials from the Kulikovskoe deposit...  相似文献   
88.
Glass and Ceramics - A system for technological regulation of adverse environmental impacts (AEI) that is based on the best available technologies (BAT) was analyzed. The expediency of updating the...  相似文献   
89.
The article presents the results of metallographic study of low-carbon 20 steel grade and high-carbon 70 and 65G steel grades upon carburizing, heat treatment, and laser hardening. The change in the microhardness through the depth of the surface layer of steels and their abrasion resistance upon hardening under different conditions has been measured. Optimal hardening conditions have been proposed for steels for cutting blades of tillage machines that enable the durability of the blades to be improved.  相似文献   
90.
Russian Engineering Research - In research on thread cutting, the flaws inevitably arising in the first two and last two turns of the thread, when the process is unsteady, are analyzed....  相似文献   
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