Population distribution problems and policies in Asia

"The main purposes of this paper are (1) to identify the primary population distribution problems in Asia, and (2) to identify the range of explicit population policy instruments or packages designed to alleviate or solve existing maldistribution. As a corollary to these main goals, attempts are made to classify types of spatial population problems and policies and to compare them across nations. Additionally, a qualitative analysis is made to assess the effectiveness of population distribution policies in those cases where there are reasonable data available."     

Hydrocarbon composition and distribution in a coastal region under influence of oil production in northeast Brazil

Waters and sediments from the Potiguar Basin (NE Brazilian coast) were investigated for the presence and nature of polycyclic aromatic hydrocarbons (PAH) and aliphatic hydrocarbons. The region receives treated produced waters through a submarine outfall system serving the industrial district. The total dispersed/dissolved concentrations in the water column ranged from 10-50 ng L⁻¹ for ∑16PAH and 5-10 μg L⁻¹ for total aliphatic hydrocarbons. In the sediments, hydrocarbon concentrations were low (0.5-10 ng g⁻¹for ∑16PAH and 0.01-5.0 μg g⁻¹ for total aliphatic hydrocarbons) and were consistent with the low organic carbon content of the local sandy sediments. These data indicate little and/or absence of anthropogenic influence on hydrocarbon distribution in water and sediment. Therefore, the measured values may be taken as background values for the region and can be used as future reference following new developments of the petroleum industry in the Potiguar Basin.     

Removal of river-stage fluctuations from well response using multiple regression

Many contaminated unconfined aquifers are located in proximity to river systems. In groundwater studies, the physical presence of a river is commonly represented as a transient-head boundary that imposes hydrologic responses within the intersected unconfined aquifer. The periodic fluctuation of river-stage height at the boundary produces associated responses within the adjacent aquifer system, the magnitude of which is a function of the existing well, aquifer, boundary conditions, and characteristics of river-stage fluctuations. The presence of well responses induced by the river stage can significantly limit characterization and monitoring of remedial activities within the stress-impacted area. This article demonstrates the use of a time-domain, multiple-regression, convolution (superposition) method to develop well/aquifer river response function (RRF) relationships. Following RRF development, a multiple-regression deconvolution correction approach can be applied to remove river-stage effects from well water-level responses. Corrected well responses can then be analyzed to improve local aquifer characterization activities in support of optimizing remedial actions, assessing the area-of-influence of remediation activities, and determining mean groundwater flow and contaminant flux to the river system.     

SHARAD study on the structures and permittivity of a buried impact crater in Martian Central Elysium Planitia

The Elysium Planitia, located in the transition zone between the northern and southern hemispheres, is one of the key areas for studying the stratigraphic structure and geological history of Mars. Previous studies have shown that this plain has undergone complex surface modification processes including fluvial and volcanic processes, and systematic progress has been made in the study of macro-geological processes. However, there are relatively few studies on the regional structure of the plain,w...