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141.
The main aim of this article is to analyze the relationships between the spatial patterns of residential burglaries and the socioeconomic characteristics of neighborhoods in London, Ontario. Relative risk ratios are applied as a measure of the intensity of residential burglary. The variation in the risks of burglary is modeled as a function of contextual neighborhood variables. Following a conventional (global) regression analysis, spatial variations in the relationships are examined using geographically weighted regression (GWR). The GWR results show that there are significant local variations in the relationships between the risk of residential burglary victimization and the average value of dwellings and percentage of the population in multifamily housing. The results are discussed in the context of four hypotheses, which may explain geographical variations in residential burglary. The practical implication of the GWR analysis is that different crime prevention policies should be implemented in different neighborhoods of the city. 相似文献
142.
Hervé Cabot Christian Meynadier Dorota Sobczyńska Barbara Szabelska Jacek Szabelski Tadeusz Wibig 《Astroparticle Physics》1998,9(4):269-276
We describe the possible measurable difference in the Cherenkov light component of EAS induced by an electromagnetic particle (i.e., e+, e− or γ) and induced by a hadron (i.e., proton or heavier nuclei) in the TeV range. The method can be applied in experiments which use wave front sampling method of EAS Cherenkov light detection (e.g., THEMISTOCLE, ASGAT). 相似文献
143.
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145.
Assessment of the Accuracy of SRTM C- and X-Band High Mountain Elevation Data: a Case Study of the Polish Tatra Mountains 总被引:1,自引:0,他引:1
Global digital elevation models (DEMs) are an invaluable source of information in large area studies. Of particular interest are shuttle radar topography mission (SRTM) data that are freely available for the scientific community worldwide. Prior to any application, global datasets should be evaluated using reference data of higher accuracy. Therefore, the main objective of this study was to assess the accuracy of the SRTM C-band (version 4) DEM and SRTM X-band DEM of mountainous areas located in Poland and to examine the quality of data in relation to topographic parameters, radar beam geometry, initial voids in data and the presence of forest cover. A DEM from the Central National Geodetic and Cartographic Inventory, Poland, served as a reference. The study consisted of three steps: (i) the computation of vertical errors of the SRTM C- and X-band DEMs, (ii) the examination of any systematic bias in the data, and (iii) the analysis of the relationships between the elevation errors and terrain slope, aspect, local incidence angle, occurrence of voids and land cover. We found that the SRTM C- and X-band DEMs have mean errors equal to 4.31 ± 14.09 and 9.03 ± 37.40 m and root mean square errors equal to 14.74 and 38.47 m, respectively. Only 82 % of the C-band DEM and 74 % of the X-band DEM vertical errors had absolute values below 16 m. We found that the most important factors determining the occurrence of high errors were the distribution of initial voids and high slope angles for the C-band DEM, and local incidence angle, slope, aspect and radar beam geometry for the X-band DEM. In both cases, the presence of forest cover increased the mean error by approximately 10 m. 相似文献
146.
The paper contains an analysis of S-velocity distribution in the crust and upper mantle beneath the Bohemian Massif, which is the second biggest Variscan outcrop
in Europe. It occupies mainly the west part of Czech Republic and also part of south-west Poland and south-east Germany. We
use data from 10 permanent stations set in the region. Some previous papers relate to the same scope but use linear methods
to inverse receiver function. Our new approach involves Monte Carlo techniques for inversion procedure, which is more convenient
and robust for such a non-linear task. The result of Monte Carlo inversion is compared with the previously achieved one. The
obtained Moho depths vary from 29 km in the north-west part of the Bohemian Massif to 38 km in the south and south-east and
are consistent with other papers. Some discrepancies occur in the middle and upper crust. 相似文献
147.
Lidia Dzierzbicka-Glowacka Jacek Piskozub Jaromir Jakacki Stella Mudrak Maria Iwona ?mijewska 《Journal of Oceanography》2012,68(6):887-904
In the present study, we used a 3D Coupled Ecosystem Model of Baltic Sea version 1 (3D CEMBSv1) coupled with a copepod model to examine the spatiotemporal distribution of two representative copepod populations in the Gulf of Gdansk (southern Baltic Sea) including Acartia spp. and Pseudocalanus minutus elongatus. The annual cycles simulated for 2000 under realistic weather and hydrographic conditions were studied with the three-dimensional version of the coupled ecosystem-copepod model in the south-eastern Baltic Sea. The paper presents the comparison of simulated and observed copepod development at two stations in the Gulf of Gdansk. A validation of influential state variables gives confidence that the model is able to calculate reliably the stage development of dominant species in the southern Baltic Sea. The number of generations was one for P. m. elongatus and 3?C5 for Acartia spp.. A mean of five generations for the latter species per year were estimated in the coastal region and ca. three generations at the Gdansk Deep (in the open sea). Food concentration and temperature as the main factors controlling the development of the investigated copepods as well as salinity as a masking factor (i.e. salinity modifies the rate of their development) in the case of Pseudocalanus minutus elongatus are included in the present study. 相似文献
148.
Maps of shallow depth (down to −250 m) temperature distribution across Canada show large variability, related mainly to surface
climatic forcing. Very small changes of temperature with depth in the upper 250 m are related to heat gained by the subsurface
due to recent global warming. Temperature data compiled from precise temperature logs in equilibrium wells, and temperature
time series from a network of meteorological stations, allow calculation of the available heat energy for heating in the cold
period and for cooling in peak warm months. Utilization of this energy resource has the potential for significant CO2 reduction in Canada. The geothermal energy stored in the ground can be used, with the help of heat pumps, for heating, given
very low winter temperatures. The amount of potential heat available is vast. In Canada, south of permafrost border, the integrated
value of potentially available heat during the heating season down to −50 m is 1.1 E21 J (1100 quads). 相似文献
149.
Functional space inversions (FSI) of precise temperature logs from wells located in low conductivity clastic sediments of the western Canadian Sedimentary Basin show evidence of extensive, recent ground surface temperature (GST) warming. Simultaneous inversion of the data, as well as averaging of the individual site reconstructions, indicate that this high magnitude of GST warming exceeds over two times that of globally averaged GST's [Science 282 (1998) 279] and is significantly higher than that of surface temperature histories based on instrumental records and tree ring reconstruction in northern and western Canada [Holocene 7 (1997) 375; Science 278 (1997) 1251; Clim. Res. 12 (1999) 39]. 相似文献
150.
Marcin Szwagrzyk Dominik Kaim Bronwyn Price Agnieszka Wypych Ewa Grabska Jacek Kozak 《Natural Hazards》2018,94(1):227-240
Flooding is a major environmental hazard in Poland with risks that are likely to increase in the future. Land use and land cover (LULC) have a strong influencing on flood risk. In the Polish Carpathians, the two main projected land use change processes are forest expansion and urbanization. These processes have a contradictory impact on flood risk, which makes the future impact of LULC changes on flooding in the Carpathians hard to estimate. In this paper, we investigate the impact of the projected LULC changes on future flood risk in the Polish Carpathians for the test area of Ropa river basin. We used three models of spatially explicit future LULC scenarios for the year 2060. We conduct hydrological simulations for the current state and for the three projected land use scenarios (trend extrapolation, ‘liberalization’ and ‘self-sufficiency’). In addition, we calculated the amount of flood-related monetary losses, based on the current flood plain area and both actual and projected land use maps under each of the three scenarios. The results show that in the Ropa river, depending on scenario, either peak discharge decreases due to the forest expansion or the peak discharge remains constant—the impact of LULC changes on the hydrology of such mountainous basins is relatively low. However, the peak discharges are very diverse across sub-catchments within the modeling area. Despite the overall decrease of peak discharge, there are areas of flow increase and there is a substantial projected increase in flood-related monetary losses within the already flood-prone areas, related to the projected degree of urbanization. 相似文献