The migration of the Danagla to port Sudan: A case study on the impact of migration on the change of identity

The study of the history and dynamics of the migration of the Danagla to Port Sudan proves that they belong to the most active groups in the Sudan. Though they have completely dropped their agricultural background and adopted an entirely urban character they still have close contacts both to each other in town and to their home land. Their migration is, nontheless, a permanent one.     

Flow against dispersion in two-dimensional regions

In field applications, upstream spreading of contaminant plumes may be controlled by the flow of fresh water in a direction opposite to the dispersive expansion direction of the plume. In the current literature this type of control is identified as flow against dispersion or contrary flow. In this study analytic methods are used to investigate contrary flow conditions for two-dimensional applications. In particular, special attention is given to the dispersive spread of the contaminant plume in the transverse direction under equilibrium flow against dispersion. Typical problems analyzed emphasize the effect of adsorption and transverse dispersion on the overall control process. Problems analyzed indicate that equilibrium flow velocities deduced from one-dimensional analysis, which may balance the dispersive spread of the plume in the longitudinal direction, represent an over design condition when these equilibrium velocities are compared with the conditions generated from a two-dimensional model for a downstream source which is finite in the transverse direction.     

Automatic near-photorealistic 3-D modelling and texture mapping for rectilinear buildings

Three-dimensional (3-D) representations of urban regions have gained much attention because of recent developments in remote sensing and computer graphics technologies. In particular, textured 3-D building reconstruction for a variety of applications has been a popular research topic in recent years. In this study, we present the reconstruction of 3-D building models along with texture selection and mapping. Extracted two-dimensional building patches and normalized digital surface model (nDSM) data are used to generate the 3-D models. To build near-photorealistic 3-D models, the acquired geo-referenced facade textures are associated with the corresponding building facades using an automated GPS-assisted approach. On the other hand, the modelling and texture mapping of the roof structures were carried out manually. The study area is composed of eight housing estates (blocks), where a total of 110 buildings were analysed. The whole study area was modelled, with facade textures, in less than 1 min of processor running time with an acceptable level of accuracy. The texture mapping was carried out using MATLAB’s Virtual Reality Toolbox?.     

Heavy metal pollution and acid drainage from the abandoned Balya Pb-Zn sulfide Mine,NW Anatolia,Turkey

This study was conducted to determine the effects of the waste-rock dump (WRD) of the underground polymetallic Balya Mine on the Kocacay River and eventually on Lake Manyas in Turkey. Data presented in this paper include geochemical characteristics of various kinds of water (mine, surface and groundwater) and of suspended-particle samples in the vicinity of Balya. The more polluted mine waters have low pH and high conductivity, while high concentrations of Zn, Cd, Mn tend to be found in the dry and wet seasons. High concentrations of Pb, As, Cr, Cu and S appear only in the wet season. The sources of the heavy metal concentration within the Kocacay River are leached waste, surface run off, and overflow from the spillway of the WRD. To minimize the formation of acids and dissolved metal, and for the remediation of the harmful effects of extreme contamination conditions, it is recommended that lime or alkali materials and organic carbon be added to simulate the action of sulfate-reducing bacteria.