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41.
The problem of estimating the proportion of lithological (ore) types in volumes of mineral deposits is considered when an auxiliary variable Z(z) is observed along with the lithology L(x) at x. The process {Z(x)} is assumed to be stationary and an assumption on the statistical relationship between {Z(x)} and {L(x)} processes is made. Consequently, the second-order stationarity of {L(x)} is not required. A method using the kriged distribution of the auxiliary variable is proposed. A case study illustrating the procedure is given.  相似文献   
42.
A. Patel  N.J. Balmer  P. Pleasence 《Geoforum》2008,39(6):2084-2096
Despite limited research on access to advice services, it has long been assumed that access is related to geographic proximity [e.g. Blacksell, M., 1990. Social Justice and access to legal services: a geographic perspective. Geoforum 21 (4), 489–502]. The current study uses data from the English and Welsh Civil and Social Justice Survey, a large-scale nationally representative survey of respondents’ experience of and response to civil and social justice problems [Pleasence, P., 2006. Causes of Action: Civil Law and Social Justice, second ed. TSO, Norwich], to examine the impact of proximity to mainstream advice services on awareness and utilisation of services. In general, proximity of advice services had a relatively modest impact on both awareness and advice seeking. However, proximity did impact upon mode of contact and there was some evidence of difference in strategy (particularly more inaction) for isolated individuals without use of motorised transport. The suitability of different modes of advice provision for particular demographic groups are discussed, as well as implications for service delivery.  相似文献   
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On some shores the seawater is muddy, contaminated with fine silt and clay in suspension. If it became necessary to use such seawater it would be essential either to resort to filtration or to allow for settling of soil sediments. The present scheme was undertaken with a view to providing clear seawater for experimentation in growing crops and plants with seawater. The system consisted of a filtration unit embedded in the shore over which the tidal water passes. The clear water is run through a conveying assembly and is stored in a sump for end uses. The design, construction materials and construction operation of such a device on coastal sand dunes has been described in detail. The precautions to be taken under such circumstances are also given.  相似文献   
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Exhumation has been recognised as a key factor in understanding the dynamics of a mountain belt. Normal faulting, erosion and ductile thinning are the three basic mechanisms to exhume the deeper high grade metamorphic rocks to the surface. Convergent orogenic belts are characterised by over-thickening of the crust due to thrusting and folding. The interplay of uplift due to over-thickening of crust and climatic-erosion is the most plausible mechanism of exhumation as suggested by the numerical models and analogue experiments. The analysis of 534 thermo-chronological dates through 1D-thermal numerical model in the Himalaya suggest that the exhumation is dominantly due to erosion but the pattern of erosion is controlled by local tectonic activities in different sector of the Himalaya since Miocene, indicating that tectonic force as the prime mechanism of exhumation in Himalaya.  相似文献   
48.
The application of piezo-ceramic elements for measuring shear and compression wave velocities in the soil mass is increasing day-by-day. Depending upon the configuration and polarity, these elements can either be used as benders or extenders, which can transmit and receive shear and compression waves, respectively. Though, several researchers have successfully employed these elements for characterizing the soil mass based on the shear and compression wave velocities, determination of the “time lag” between the input and output waves remains debatable. Even, the existing literature does not clearly present the response of these elements with respect to the frequency of excitation and the type of the material to be characterized. With this in view, extensive investigations were made to capture the performance of piezo-ceramic elements by changing their (a) wiring configuration (i.e., series or parallel) and (b) polarization (i.e., same or opposite) in the compacted soils of different characteristics (i.e., moisture content, dry density and type of the soil). Details of the methodology are presented in this paper and special attention has been paid to address various problems (i.e., wave attenuation, crosstalk phenomena, near field effect and overshooting of transmitting waves) that are associated with signal interpretation and may yield misleading results.  相似文献   
49.
Well preserved ichnofossils were found in Kulakkalnattam sandstone exposed at Kulakkalnattam stream in Ariyalur area, Cauvery Basin. It consists of infaunal structures of both suspension and deposit feeders. Five ichnofossils are present in a fine to coarse grain sandstone which includes Ophiomorpha, Palaeophycus, Planolites Skolithos, and Thalassinoides. The study infers that ichnofossils Skolithos and Ophiomorpha are infaunal colonization of the suspension feeders in high energy condition in shifting substrate, whereas Thalassinoides and Planolites-Palaeophycus ichnofossils indicate infaunal deposit feeders living at the sediment-sediment interface in low to moderate energy conditions. Furthermore, the abundance and diversity of the trace fossils indicates there was alternatively fluctuations in energy conditions which lead to development of Skolithos and Cruziana ichnofacies type condition during the deposition of Kulkkallanattam sandstone in foreshore-shoreface environments.  相似文献   
50.
Nanofiltration of ternary mixtures of sodium chloride and aqueous solutions of Reactive Black-5 was studied in two different modules, namely, flat sheet and spiral wound over a wide range of operating conditions. Hydrophilized polyamide membrane with molecular weight cutoff of 150 was used for the experiments. Combined effect of dye and salt concentration, trans-membrane pressure drop, initial pH of feed solution on the permeate flux, and observed retention were investigated. Extent of color removal, chemical oxygen demand (COD), total dissolved solid (TDS), and conductivity were determined to assess performance of the membrane. The experimental results showed that both the permeate flux and observed retention decreased with increase in dye as well as salt concentration in the feed. Permeate fluxes were lower at higher pH values. Substantial removal of color was achieved in the nanofiltration experiments with a marked reduction in COD and TDS. The process allowed the production of permeate stream with great reutilization possibilities.  相似文献   
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