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1.
This paper describes an application of the geographic information system (GIS) technology to a ground stability assessment in the karst area of Dzerzhinsk, Russia. In the stability analysis, the groundwater level changes in the karst aquifer could cause suffosion sinkholes when the gravitational force was greater than the soil strength. The GIS technology was used to combine various data and to delineate the zones of potential gravitational collapse and suffosion collapse in the area.
V. V. TolmachevEmail:
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2.
Important aspects of melt inclusion formation and potential compositions effects have been addressed through a series of experiments using anorthite/fosterite saturated anhydrous mafic liquids. Experimental charges were cooled from 1,300 to 1,230 and 1,210°C at rates of 1–10°/min followed by 0–24 h isothermal periods. Hopper and skeletal crystal morphologies with variable degrees of completeness developed during the cooling period. Planar overgrowth of these textures during isothermal periods led to the formation of inclusions, the majority of which formed after 6 h of isothermal run time. We suggest that the change in morphologies is related to a decrease in growth rates and changes in dominant growth mechanisms. In general, inclusion compositions were uniform and similar to the host glass, indicating that with the isothermal times required for most inclusions to form, a boundary layer was not entrapped that could be detected within the limits of our analyses.
Edward KohutEmail: Phone: +1-541-7373023Fax: +1-541-7371200
Roger L. NielsenEmail: Phone: +1-541-7371235
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3.
Crustal-scale shear zones may act as prominent electrical conductors given that sufficient amounts of graphite or fluids are present. There are several graphite-enriched shear zones within the 583-m-deep Rittsteig drilling (Bavaria, Germany), two of which are of major importance. One shear zone cuts through Moldanubian biotite-muscovite schists at 320 m depth. The other shear zone separates Teplá-Barrandian amphibolites from Moldanubian biotite-muscovite schists at 460 m depth. To detect these shear zones adjacent to the drilling, the self-potential method and the non-linear impedance spectroscopy have been applied. From the new data, obtained from hole-to-surface and surface measurements, we conclude that (1) graphite is pervasively distributed within the Rittsteig shear zones resulting in powerful electronic conductors, (2) the graphite-bearing shear zones are dipping moderately towards the S, and (3) the shear zone drilled at 320 m depth extends to the Earths surface where it has been detected ca. 400 m to the N of the drilling. As the graphite-bearing shear zones of both the Rittsteig drilling and the German Continental Deep Drilling (KTB) developed in the brittle-ductile regime of quartzofeldspathic rocks, we argue that the brittle-ductile boundary layer may act as a significant graphite attractor in the continental crust.
Gernold ZulaufEmail: Phone: +49-9131-8522617Fax: +49-9131-8529295
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4.
Using density functional simulations, within the generalized gradient approximation and projector-augmented wave method, we study structures and energetics of CaSiO3 perovskite in the pressure range of the Earths lower mantle (0–150 GPa). At zero Kelvin temperature the cubic CaSiO3 perovskite structure is unstable in the whole pressure range, at low pressures the orthorhombic (Pnam) structure is preferred. At 14.2 GPa there is a phase transition to the tetragonal (I4/mcm) phase. The CaIrO3-type structure is not stable for CaSiO3. Our results also rule out the possibility of decomposition into oxides.
Daniel Y. JungEmail: Phone: +41-44-6323744Fax: +41-44-6321133
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5.
Hydrology of the coastal sabkhas of Abu Dhabi, United Arab Emirates   总被引：2，自引：0，他引：2  
Water fluxes were estimated and a water budget developed for the land surface and a surficial 10-m-deep section of the coastal sabkhas that extend from the city of Abu Dhabi, United Arab Emirates, west to the border with Saudi Arabia. The fluxes were estimated on the basis of water levels and hydraulic conductivities measured in wells and evaporation rates measured with a humidity chamber. In contrast with conceptual models proposed in earlier studies, groundwater inflow is estimated to be small, whereas the largest components of the water budget are recharge from rainfall and evaporation from the water table. Estimates within a rectilinear volume of sabkha, defined as 1 m wide by 10 km long by 10 m deep, indicate that about 1 m3/year of water enters and exits by lateral groundwater flow; 40–50 m3/year enters by upward leakage; and 640 m3/year enters by recharge from rainfall. Based on the water and solute fluxes estimated for the upward leakage into the sabkha, 7–8 pore volumes of brine have entered the sabkha from below since the time the sabkha became saturated (7,000 years ago) as a result of the last global sea-level rise.
Ward E. SanfordEmail:
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6.
The pattern of Church of England dioceses has evolved over a period of 1,400 years. It reflects the practical response of the Church to the changing political and demographic patterns of the country. No ideal size and form of diocese was ever devised and few systematic attempts were made to achieve a degree of equity between them. The constitutional link between state and church has inhibited change for the last 80 years, although society has changed significantly. Nevertheless, rapid constitutional reforms, especially in the House of Lords, may be reflected in ecclesiastical reorganisation of the dioceses.
Anthony John ChristopherEmail:
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7.
Materials properties of barricade bricks for mining applications   总被引：1，自引：0，他引：1  
Barricade bricks are fundamental to the safe operation of a mining site. Past failures have lead to loss of life and reduced mine efficiency or even shut down. The fundamental material property that determines the operational characteristics of barricade bricks is their permeability, which must be tailored to suit the operational environment of the mine. The ability of the barricade to control the hydraulic pressure within a stope application is crucial for safety and economic returns. In the current work practical barricade bricks were tested for permeability. As well, the strength and modulus of bricks were measured after being soaked in water for either 7 or 90 days so that a measure of their engineering functionality could be determined. The primary conclusions of this work are as follows. There was substantial deviation in permeability between bricks; however, the average permeability of the barricade bricks was several orders of magnitude larger than the values obtained for the hydraulic fill. This difference indicates that modelling efforts can assume that the barricade does not contribute to the pore pressure development within the fill. Hence the drainage of the system is not related to the permeability of these bricks provided that the barricades are built from the bricks in such a way that the construction or future migration of fines from the fill does not impede the drainage performance.
Christopher C. BerndtEmail:
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8.
This paper examines the effect of economic interdependence, intergovernmental organizations, political freedom, and spatial relationship on foreign diplomatic presence in the U.S. from 1980 to 2000. Spatial perspective is largely missing in the mainstream international theories. Spatial relationship has three measures: spatial proximity measured as distance, spatial dependency measured as neighborhood effect, and spatial heterogeneity measured as regional effect. We found that the effect of economic interdependence is directional. The U.S. sensitivity to foreign trade rather than foreign sensitivity to trade with the U.S. explains much of the variation in the foreign diplomatic presence in the U.S. Spatial effect is mainly manifested as spatial dependency; the effects of geographic proximity and geographic regions on foreign diplomatic presence are, however, mild. Spatial dependency in the variation of foreign diplomatic presence in the U.S. could not be well explained by the liberal perspective without using the spatial model.
Lin Liu ([Summer Visiting Professor])Email:
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9.
The paper compares the results of two studies of salt damage at the Wakefield Tower, Tower of London. The first, in 1993, was based on semi-quantitative salt analysis and hygroscopicity measurements. The second was based on quantitative analysis and a thermodynamic model, ECOS. Both studies aimed to predict environmental conditions that would minimise salt damage to the interior stonework. Their predictions are markedly different, and this paper examines the reasons for the differences. It is shown that hygroscopicity alone is not a reliable indicator of crystallisation from mixed salt solutions.
Clifford A. PriceEmail:
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10.
A vulnerability index for the Fire Service in the UK has been designed to identify vulnerable locations during episodes of severe floods. Taking recent case studies with the UK Fire Service, the patterns of vulnerability, in terms of demand on time and resources, can be explained by investigating the environmental causes and their interaction with the adaptive capacity of the response agencies.
Dorian SpeakmanEmail:
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11.
The single-crystal acoustic velocities of α- and β-quartz were measured by Brillouin spectroscopy to a maximum temperature >1,500°C at room pressure. From these velocities, the single-crystal elastic moduli were calculated up to 1,050°C, exceeding the temperature range of previous measurements by 350°C for the elastic moduli and by 710°C for acoustic velocities. The ordinary refractive index (n o) of α- and β-quartz was measured from room temperature to 800°C. In the temperature interval from ∼950 to 1,000°C a subtle change in the temperature derivative of the longitudinal acoustic velocity was observed in platelet geometry for all measured directions. The high-temperature acoustic velocity data may indicate the presence of a second phase, presumably β-cristobalite, that nucleates below 1,000°C.
Dmitry L. LakshtanovEmail:
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12.
Summary  The question of alternative technologies for high-speed Internet access lies at the heart of rural development problems. In this paper, we focus on one of those technologies, the system combining satellite technologies and Wi-Fi. Based on an empirical study carried out in three rural areas, we analyze the dynamics of the use and appropriation of that technology by the companies and organizations participating in the experiment. Considered both from a technical and social standpoint, the technology ‘in use’ appears here in its structuring dimensions.
Valérie FautreroEmail:
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13.
The effects of permeability variability on uncertainty of the results of a hydrocarbon biodegradation model are addressed. The model includes saturated and unsaturated flow, multi-species transport, heat transport, and bacterial-growth processes. A stochastic approach was used in the uncertainty analysis. Sensitivity analyses were conducted, taking into consideration the effects of heterogeneity. The Monte Carlo method was used, with permeability as the input stochastic variable. Results showed that uncertainty increases with time. This can lead to difficulties regarding cleanup decision making such as predicting the timeframe to reach an aquifer cleanup goal. It was not possible to replace the heterogeneous system with a homogeneous one through the use of effective parameters that preserve an equivalent behavior of the two systems. Effective permeability is space and time dependent and also depends on values of bioactivity parameters. The study also emphasized the importance of accurately measuring certain bacterial parameters, namely, maximum substrate uptake rate for degradation and cell yield coefficient. Uncertainties regarding nutrient and oxygen uptake and saturation parameters were less important for the current application.
Aly I. El-KadiEmail:
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14.
Over the last 20 years, many tools have been developed for the prediction of the post-failure behaviour of rapid landslides. However, as pointed out by several researchers, knowledge may be improved by the performance of back-analyses using different models and the evaluation of their reliability. This paper reports the back-analysis, conducted using numerical models, of 57 rapid landslides that have occurred in the Campania region. The back-analysis has been performed using the 2-D DAN_W code (version 2003) with two different rheological models: the Voellmy and the frictional models. The latter has been immediately discarded because it did not match the observed data. Instead, using the Voellmy model, the best-fit values of the parameters (friction μ and turbulence ξ) for different types of flow (channelled, un-channelled and mixed flows) have been researched. With these values a parametric study has been carried out on four representative slope profiles of the Campania region, enabling the prediction of runout, velocity and depth of flow (dynamic parameters) of potential debris flows.
Anna Scotto di SantoloEmail:
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15.
Crystallization of salts is recognized to be a major factor of the degradation of porous materials such as stone and concrete. On the theoretical side, there is now general acceptance about the thermodynamic origin of this phenomenon. However, on the experimental side, there are only scarce quantitative data. In this respect, the reference work par excellence is that of Correns (Discuss Faraday Soc 5:267–271, 1949) who shows a good correlation between calculated and measured crystallization pressures. However, concerns about both the thermodynamic derivation and the experimental conditions raise the question about why Correns could have obtained such a good correlation. This issue is discussed extensively in this paper which is organized as a commented translation of a former paper by Correns, co-authored by Steinborn, and that is much richer in experimental details.
Robert J. FlattEmail:
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16.
Tornado shelters and the manufactured home parks market   总被引：2，自引：2，他引：0  
Manufactured or mobile homes represent a fast growing portion of the housing market but are particularly vulnerable to tornadoes. In the US over 40% of tornado fatalities occur in mobile homes even though they comprise about 8% of US housing units. We examine the market for tornado shelters in manufactured home parks in Oklahoma. Almost 60% of parks in the state have shelters, with 90% of the shelters underground. Parks with shelters are not concentrated in urban areas but spread across the state, with parks with shelters in 32 counties. We find that rents for lots in parks with shelters are 5–8% higher, which generates sufficient revenue to approximately pay for shelters, but the point estimate is statistically significant in only one specification.
Daniel Sutter (Corresponding author)Email:
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17.
Sarah F. Ives 《GeoJournal》2009,74(3):245-255
Using a discussion of South African soap operas, I will place the idea of visuality in a discourse analysis that incorporates a feminist epistemological lens, or an epistemology that integrates reflexivity and an acknowledgment of the dialogic nature of visual media. Through this discussion, I will examine the possibilities that dialogism provides for unpacking and exploring the politics of imperfect translation between the visual and the textual. These methodological interventions, I argue, will help enrich discussions of the visual’s role in the contested realm of geographic imaginations and move beyond the distanced position of the masculine gaze.
Sarah F. IvesEmail:
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18.
Approximately 1.2 km of dolomitic limestone overlies the Far West Rand gold reefs southwest of Johannesburg, South Africa. This karst aquifer is partitioned into several groundwater compartments by predominantly north–south trending syenite dykes. Prior to mining, the primary water flow was westwards, decanting over dyke boundaries as a succession of springs along the Lower Wonderfontein Spruit. Dewatering of the overlying dolomitic aquifer for safety and economic reasons by deep gold mining operations, caused the water levels of four compartments to drop and their respective springs to dry up. By perforating dykes, formerly separated aquifers were hydraulically interconnected by mining. Using historical and recent data of water flow—surface and groundwater—and pumping rates, a geohydrological model is presented. The results suggest that the water tables will rise to their pre-mining levels within 30 years after mining ceases and that the dry springs will flow again, despite the compartments being connected by the extensive mining operations.
C. J. U. SwartEmail: Phone: +27-18-7874435Fax: +27-18-7875972
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19.
In order to study the ongoing tectonic deformation in the Rhine Graben area, we reconstruct the local crustal velocity and the strain rate field from GPS array solutions. Following the aim of this work, we compile the velocities of permanent GPS stations belonging to various networks (EUREF, AGNES, REGAL and RGP) in central western Europe. Moreover, the strain rate field is displayed in terms of principal axes and values, while the normal and the shear components of the strain tensor are calculated perpendicular and parallel to the strike of major faults. The results are compared with the fault plane solutions of earthquakes, which have occurred in this area. A broad-scale kinematic deformation model across the Rhine Graben is provided on the basis of tectonics and velocity results of the GPS permanent stations. The area of study is divided into four rigid blocks, between which there might be relative motions. The velocity and the strain rate fields are reconstructed along their borders, by estimating a uniform rotation for each block. The tectonic behaviour is well represented by the four-block model in the Rhine Graben area, while a more detailed model will be needed for a better reconstruction of the strain field in the Alpine region.
Magdala TesauroEmail:
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20.
Spatial and temporal knowledge representation   总被引：1，自引：1，他引：0  
Knowledge Representation (KR) originated as a discipline within Artificial Intelligence, and is concerned with the representation of knowledge in symbolic form so that it can be stored and manipulated on a computer. This article surveys that part of KR that is concerned with the representation of space and time, with particular reference to the use of such representations in geographical information science.
Antony GaltonEmail:
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