Analyzing spatial disparities in access to health care: A methodology with application in Bangladesh

This paper develops a methodology for analyzing spatial disparities in access to health care in situations where the data base is limited, and applies it in the context of Bangladesh. The proposed indirect measures of inpatient and outpatient service utilization, and of quality of available services, seem to provide reasonably accurate, consistent, and interpretable results; these indices are combined into a composite index of relative access to health care. The form of the composite index and its components permits the incorporation of Sopher's disparity index into the methodology for measuring urban-rural disparities in relative access to health care. The empirical analysis based on subdivision level data revealed that Bangladesh's health care delivery system is, in general, characterized by extremely low level of access and a high degree of disparity in favor of urban areas, especially in terms of inpatient services. Spatial patterns of relative access and urban/rural disparity were perused through cartographic and statistical analyses; although clear-cut regional patterns did not emerge, the considerable spatial variations could be explained largely with reference to urbanization and density of population. Assuming improved level of access and minimal urban/rural disparity as basic policy goals a method to prioritize spatial units for future allocation of health sector resources is recommended.The author gratefully acknowledges the helpful comments on an earlier draft of this paper by Dr. S. M. Bhardwaj, Professor of Geography, Kent State University.     

Application of a two-dimensional electrical tomography technique for investigating landslides along the Amman–Dead Sea highway, Jordan

Electrical tomography geophysical surveys were conducted with the SYSCAL-R2 resistivity instrument at the location of instantaneous rock failure of a few 1,000s m³ along the Amman-Dead Sea highway, Jordan, providing a ground image for investigating landslide sites which caused material damage and closed the road. This slide occurred along two major fault planes after heavy rainfall in a rock consisting of a succession of shale, marl and marly limestone layers which were folded, tilted and fractured. Three electrical tomography profiles were performed along the axis of the slope to assess the landslide risk in such potential unstable areas. The results obtained, based on two-dimensional inversion of field data, have allowed mapping of the shale zones at depths which are characterized by a lower resistivity value, and have demonstrated that the rupture was initiated at the contact between the shale mass (black colored) and the massive limestone (white, yellowish-brown colored).     

Area Influence Kriging

This paper presents a modified ordinary kriging technique referred to as the “Area Influence Kriging” (AIK). The method is a simple and practical tool to use for more accurate prediction of global recoverable ore resources in any type of deposit. AIK performs well even in deposits with skewed grade distributions when the ordinary kriging (OK) results are unreasonably smooth. It is robust and globally unbiased like OK. The AIK method is not intended to replace OK, which is a better estimator of the average grade of the blocks. Rather it aims to complement OK with its excellent performance in predicting recoverable resources that have been the major pitfalls of OK in many resource estimation cases. The paper details the methodology of AIK with a couple of examples. It also reports the results from its application to a gold deposit.     

An assessment of the impact of urbanization and land use changes in the fast-growing cities of Saudi Arabia

Understanding rates, patterns and types of land use and land cover (LULC) changes are essential for various decision-making processes. This study quantified LULC changes and the effect of urban expansion in three Saudi Arabian cities: Riyadh, Jeddah and Makkah using Landsat images of 1985, 2000 and 2014. Seasonal change of vegetation cover was conducted using normalised difference vegetation index, and object-based image analysis was used to classify the LULC changes. The overall accuracies of the classified maps ranged from 84 to 95%, which indicated sufficiently robust results. Urban area was the most changed land cover, and most of the converted land to urban was from bare soil. The seasonal analysis showed that the change of vegetation cover was not constant due to climatic conditions in these areas. The agricultural lands were significantly decreased between 1985 and 2014, and most of these lands were changed to bare soil due to dwindling groundwater resources.     

Determining Water Depths for Monitoring Coastal Water Quality Using Multiple Functional Traits of Periphytic Protozoa in Marine Ecosystems

Ocean Science Journal - Biological trait analysis (BTA) of protozoan communities has been used a useful bioindicator of environmental quality status in marine ecosystems. To determine the optimal...     

Algal community and pollution indicators for the assessment of water quality of Ismailia canal,Egypt

Stochastic Environmental Research and Risk Assessment - The phytoplankton community structure is affected by both ecological and spatial factors. Influences of these two factors on phytoplankton...     

Aquifer Treatment of Sea Water to Remove Natural Organic Matter Before Desalination

An investigation of a sea water reverse osmosis desalination facility located in western Saudi Arabia has shown that aquifer treatment of the raw sea water provides a high degree of removal of natural organic matter (NOM) that causes membrane biofouling. The aquifer is a carbonate system that has a good hydraulic connection to the sea and 14 wells are used to induce sea water movement 400 to 450 m from the sea to the wells. During aquifer transport virtually all of the algae, over 90% of the bacteria, over 90% of the biopolymer fraction of NOM, and high percentages of the humic substance, building blocks, and some of the low molecular weight fractions of NOM are removed. Between 44 and over 90% of the transparent exopolymer particles (TEP) are removed with a corresponding significant reduction in concentration of the colloidal fraction of TEP. The removal rate for TEP appears to be greater in carbonate aquifers compared to siliciclastic systems. Although the production wells range in age from 4 months to 14 years, no significant difference in the degree of water treatment provided by the aquifer was found.     

Cokriging for enhanced spatial interpolation of rainfall in two Australian catchments

Rainfall data in continuous space provide an essential input for most hydrological and water resources planning studies. Spatial distribution of rainfall is usually estimated using ground‐based point rainfall data from sparsely positioned rain‐gauge stations in a rain‐gauge network. Kriging has become a widely used interpolation method to estimate the spatial distribution of climate variables including rainfall. The objective of this study is to evaluate three geostatistical (ordinary kriging [OK], ordinary cokriging [OCK], kriging with an external drift [KED]), and two deterministic (inverse distance weighting, radial basis function) interpolation methods for enhanced spatial interpolation of monthly rainfall in the Middle Yarra River catchment and the Ovens River catchment in Victoria, Australia. Historical rainfall records from existing rain‐gauge stations of the catchments during 1980–2012 period are used for the analysis. A digital elevation model of each catchment is used as the supplementary information in addition to rainfall for the OCK and kriging with an external drift methods. The prediction performance of the adopted interpolation methods is assessed through cross‐validation. Results indicate that the geostatistical methods outperform the deterministic methods for spatial interpolation of rainfall. Results also indicate that among the geostatistical methods, the OCK method is found to be the best interpolator for estimating spatial rainfall distribution in both the catchments with the lowest prediction error between the observed and estimated monthly rainfall. Thus, this study demonstrates that the use of elevation as an auxiliary variable in addition to rainfall data in the geostatistical framework can significantly enhance the estimation of rainfall over a catchment.     

Adaptive base-isolation of civil structures using variable amplification

Semi-active dampers are used in base-isolation to reduce the seismic response of civil engineering structures. In the present study, a new semi-active damping system using variable amplification will be investigated for adaptive baseisolation. It uses a novel variable amplification device （VAD） connected in series with a passive damper. The VAD is capable of producing multiple amplification factors, each corresponding to a different amplification state. Forces from the damper are amplified to the structure according to the current amplification state, which is selected via a semi-active control algorithm specifically tailored to the system＇s tmique damping characteristics. To demonstrate the effectiveness of the VAD-damper system for adaptive base-isolation, numerical simulations are conducted for three and seven-story base-isolated buildings subject to both far and near-field ground motions. The results indicate that the system can achieve significant reductions in response compared to the base-isolated buildings with no damper. The proposed system is also found to perform well compared to a typical semi-active damper.     

Seismic identification of geothermal prospecting in Harrat Rahat,Northern Arabian Shield

Influenced by mining activities in adjacent coal seams, stresses on rocks surrounding roadway were redistributed, and the roadways in lower coal seam were subjected to the asymmetrical roof falling and roof sagging. Considering stresses effect on the plastic zone around the roadway, numerical models were carried out by FLAC to investigate plastic zone with respect to stress ratio and direction of stresses. The relationship between the properties of surrounding rock and plastic zone boundary was also investigated by another numerical model and analytical study, whereby the tailgate stability of panel 30,501 in Tashan coal mine was implemented. It is shown that the rocks surrounding a roadway in the lower coal seam were subjected to unequal stresses, and the principal stress direction was deflected from the original direction. High stresses and big stress ratio can produce butterfly-shaped or X-shaped plastic zone. The direction of stresses was deflected, causing the plastic zone around the roadway to be transferred from the shoulder to the roof of the roadway. Consequently, asymmetrical stresses produce asymmetrical plastic zone. On this basis, the tailgate should be assigned conditions of the stresses and stress ratio at a low level. In this way, the tailgate was arranged at the position where the horizontal distance from the roadway in the lower seam to the centre line of the coal pillar in the upper seam (x) is 52.5 m, and was stable relatively.