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11.
Since the 1960s the analysis of small-scale surface processes has been the dominant approach in geomorphology, the previous focus on regional-scale landscape evolution having been largely abandoned as a result of the lack of knowledge of processes and process rates at the relevant temporal and spatial scales. It has recently been acknowledged that small-scale, surface process geomorphology alone is unable to provide an understanding of long-term landscape development, both because of the significance of tectonics, and because of the important role of contingency at the large temporal and spatial scales involved. But the major advances in geochronological techniques and numerical modelling of landscape evolution that are now revolutionizing our understanding of long-standing questions of landscape evolution have been largely developed and applied by researchers from outside the traditional geomorphology community. As a result, two distinct communities of researchers have emerged concerned with different scales of landform analysis, but the progress of geomorphology will be best served by greater interaction between them.  相似文献   
12.
In the last few years virtual anthropology has been used to solve different problems that could not be properly addressed using a traditional anthropological approach. Mainly when dealing with mummies or embalmed bodies, the virtual approach is the only solution to carry out a detailed analysis of the skeleton without jeopardizing the integrity of the physical remains.  相似文献   
13.
J. P. FAIRLEY 《Geofluids》2009,9(2):153-166
Previous studies have shown that most hydrothermal systems discharging at the land surface are associated with faulting, and that the location, temperature and rate of discharge of these systems are controlled by the geometry and style of the controlling fault(s). Unfortunately, the transport of heat and fluid in fault-controlled hydrothermal systems is difficult to model realistically; although heterogeneity and anisotropy are assumed to place important controls on flow in faults, few data or observations are available to constrain the distribution of hydraulic properties within active faults. Here, analytical and numerical models are combined with geostatistical models of spatially varying hydraulic properties to model the flow of heat and fluid in the Borax Lake fault of south-east Oregon, USA. A geometric mean permeability within the fault of 7 × 10−14 m2 with 2× vertical/horizontal anisotropy in correlation length scale is shown to give the closest match to field observations. Furthermore, the simulations demonstrate that continuity of flow paths is an important factor in reproducing the observed behavior. In addition to providing some insight into possible spatial distributions of hydraulic properties at the Borax Lake site, the study highlights one potential avenue for integrating field observations with simulation results in order to gain greater understanding of fluid flow in faults and fault-controlled hydrothermal and petroleum reservoirs.  相似文献   
14.
This paper considers the impact of distance to polling station upon electoral turnout. Using polling station level data from a London borough, it examines three types of election – parliamentary, European and local elections – over a twenty year period. The UK is notable among western liberal democracies for its relatively large turnout gap – the percentage point difference between turnout at elections for the Westminster parliament compared to that for other institutions, including local councils and the supra-national European parliament. This research considers the hypothesis that in high information, high salience elections for the national parliament the costs of voting associated with travelling to a polling station to vote in person are perceived as either low or insignificant but that in low information, low salience elections, those costs are perceived as higher and may act as a deterrent upon voting. A series of multi-level models consider the relationships between the dependent variable, percentage turnout, and a range of independent variables, including socio-economic characteristics, marginality as well as the spatial context. We show that there is indeed a relationship between distance and voter turnout, and other spatial and contextual variables, which are stronger for the lower salience European and local elections than for the higher salience national elections. Hence we conclude that the local geography of the polling station can have a significant impact on voter turnout and that there should be a more strategic approach to the siting of polling stations.  相似文献   
15.
A methodology is described by which spatial patterns of land use were reconstructed from pollen analyses on anthropogenic sediments at a recently excavated early Neolithic timber ‘hall’ in north east Scotland. The anthropogenic sediments were from a deep, small diameter pit within the building. They present numerous taphonomic and interpretative challenges to the analyst, but from this type of deposit, the power to estimate quantitatively the vegetation structure around the archaeological site makes such difficult deposits very significant. A rigorous methodology is firstly described, therefore, by which confidence in ecological interpretation can be established. Secondly, the source of pollen in the deposit is evaluated. Thirdly, the possible pollen source area and structure of the surrounding vegetation are estimated by quantitative simulation modelling. Finally, these analyses are compared with region-scale pollen analyses from nearby conventional wetland deposits with much larger pollen source areas. The pollen assemblages recovered probably reflect land uses adjacent to the ‘hall’ and up to 2.5 km around. Cereal cultivation was the most important land use immediately around the ‘hall’, possibly grown between stands of scrub Corylus (hazel) woodland. These intensive but local-scale land uses cannot be discerned in region-scale pollen analyses.  相似文献   
16.
The influence of relief, as well as other environmental features such as soils or the hydrological regime, on prehistoric settlement patterns is commonly accepted. Settlement patterns and preferences changed over time in different areas, so it is difficult to formulate general rules of human behaviour throughout history. In lowland areas of the temperate zone, which lack radical relief changes and have widespread access to water resources, specific settlement preferences and significant changes in these preferences are difficult to interpret.New methods developed to address the problem of the settlement transformations as a result of prehistoric settlement and economic processes using multivariate statistics have been adapted for the middle part of the Great Poland Lowland. In this region, data from the Polish Archaeological Record Project database have been used.Models of the dependence between geomorphological features and settlement intensity form the basis for estimating changes in prehistoric settlements. The degree of preference (or avoidance) is a nonparametric function of the number of archaeological sites observed in the area relative to the number of sites expected from a completely random pattern. The most crucial factors for settlement are distance to plateau edges, distance to water bodies, and the wetness index. The results show that the entire investigated area is more or less suitable for settlement, but the most occupied terrains are the areas near plateau edges.  相似文献   
17.
A new method for modelling archaeological resource potential is presented that avoids some of the mathematical violations and inconsistencies of previously-favoured techniques. The Minanha research area in west-central Belize and a database of other Maya centres from within Belize are used as a case study for demonstrating the utility of the proposed modelling technique.  相似文献   
18.
This work describes the procedures, the different techniques and the pipeline used for creating a digital framework that should assist the Superintendence of Pompeii in the digital reconstruction, classification, management and visualisation of archaeological finds inside an advanced 3D web-based repository of reality-based data. Specific topics have been focused on the quality assessment procedures adopted to ensure consistency and reliability of data throughout the whole 3D models acquisition and pipeline creation, as well as on the particular semantic reality-based structure adopted to develop an information system into a knowledge one. The main purposes of our framework have been the usage of 3D digital models as a restitution of the real object and as a metaphor for navigating through the data; 3D models were used as archaeological cognitive systems and developed as a collection of structured objects, identified through a precise terminology that allows to easily extend the concept of 2D GIS to 3D GIS. In addition, the system was developed as a scalable application that allows the use of the same database by different users, simply filtering the data according to the specific requirements, and can operate both as standalone and web-based application.  相似文献   
19.
This paper introduces GIS-based statistical methods for the study of settlement patterning in an archaeological context. The main aspect is an improvement over suboptimal stepwise statistical model selection procedures, with the introduction of a Deletion/Substitution/Addition (DSA) algorithm, a systematic model selection algorithm that provides an optimal model choice. The paper also introduces the combined use of Receiving Operator Characteristic (ROC) curves, and variable ranking as key tools aimed at an understanding of settlement patterning causation. An illustrative case study is provided whereby both a purely environmental and a mixed environmental/historical model (based on settlement hierarchy considerations) are investigated.  相似文献   
20.
Maternal mortality is a major problem in middle‐income and low‐income countries, and the availability and accessibility of healthcare facilities offering safe delivery is important in averting maternal deaths. Siaya County, in Kenya, has one of the highest maternal mortality rates in the country—far more than the national average. This study aimed to evaluate geographic access to health facilities offering delivery services in Siaya County. A mixed‐methods approach incorporating geographic information system analysis and individual data from semi‐structured interviews was used to derive travel time maps to facilities using different travel scenarios: AccessMod5 and ArcGIS were used for these tasks. The derived maps were then linked to georeferenced household survey data in a multilevel logistic regression model in R to predict the probability of expectant women delivering in a health facility. Based on the derived travel times, 26 per cent (13,140) and 67 per cent (32,074) of the estimated 46,332 pregnant women could reach any facility within one and two hours, respectively, while walking with the percentage falling to seven per cent (3,415) and 20 per cent (8,845) when considering referral facilities. Motorised transport significantly increased coverage. The findings revealed that the predicted probability of a pregnant woman delivering in a health facility ranged between 0.14 and 0.86. Significant differences existed in access levels with transportation‐based interventions significantly increasing coverage. The derived maps can help health policy planners identify underserved areas and monitor future reductions in inequalities. This work has theoretical implications for conceptualising healthcare accessibility besides advancing the literature on mixed methodologies.  相似文献   
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