Development of a DEM in the GIS “PANORAMA” Based on a Topographic Map for the Southern Territory of the Fergana Valley

Dinara Abzhaparova — 2025-08-05

The capabilities of GIS for constructing a digital elevation model of a mountainous area and visualizing a spatial image of the terrain are given in this paper. Graphic, digital data and topographic maps, which are the main sources for GIS, are described. The methods of vectorization of isolines and the requirements for technical means of processing graphic materials are presented in detail. The advantages and disadvantages of the DEM of a mountainous region are shown here. Segmentation methods using an interpolation polynomial are described in detail. A DEM of the mountainous area where the border between the republics runs was constructed in 2D and 3D formats using the GIS Panorama. Reducing the chord length when segmenting isolines on topographic maps leads to more accurate DEM construction. A vertical profile of a mountainous area with a visibility zone between two points was constructed. It is expected that the improved latitude, longitude and altitude parameters of the topographic map will be used to form a regional geodetic network and geospatial analysis of mountain ranges. It is proposed to use not only satellite data, but also classical geodetic networks and maps. It is recommended to use satellite and aerial photography to clarify the topographic and geodetic support of the studied area.

Solvent-Driven Fractional Crystallization Applied to the Desalination of a Concentrated Wastewater by Reverse Osmosis

Edgar Vásquez — 2025-08-04

This paper reports the efficiency of the solvent-driven fractional crystallization (SDFC) process using ethanol, also known as antisolvent crystallization, in the treatment of a concentrated wastewater by reverse osmosis (RO). This experiment evaluated the effects of varying the volumetric mixing ratio of ethanol-to-RO concentrate, in conjunction with the incorporation of Ca(OH)₂, on the efficiency of magnesium and boron removal. The incorporation of Ca(OH)₂resulted in an enhancement of the reduction of magnesium and boron concentrations at a mixing ratio of 85:15 (v/v) and a pH of 12. In these conditions, the removal efficiencies achieved for magnesium and boron were 98.64% and 90.82%, respectively. The findings indicate that Ca(OH)₂has a significant impact on enhancing the removal efficiencies of these elements. The RO concentrated wastewater used in this experiment exhibited a salinity of 50,497.200 ppm prior to the SDFC test. The experimental results also showed a 48.10% reduction in salinity and 28.10% salt precipitation at the maximum mixing ratio and pH level examined. The tested process demonstrated significant reduction of scaling ions including calcium, magnesium, and sulfate. Similar behavior was observed for arsenic and manganese. Moderate removal efficiencies were observed for monovalent ions such as chloride, sodium, and potassium. However, the process was no effective for iron and lithium, which showed low removal efficiencies. Based on the results obtained, SDFC technology is seen as a promising technological option for application in the treatment of complex mining wastewaters.

Journal of Environmental & Earth Sciences

Development of a DEM in the GIS “PANORAMA” Based on a Topographic Map for the Southern Territory of the Fergana Valley

Solvent-Driven Fractional Crystallization Applied to the Desalination of a Concentrated Wastewater by Reverse Osmosis