Risk analysis of meteorological, agricultural, and hydrological drought events and study of drought propagation features: a case study in the upper Tapti River sub-basin, Central India

As a natural hazard, drought is a complex multivariate phenomenon that requires more comprehensive analysis. In this study, we studied meteorological, agricultural, and hydrological drought events with precipitation, soil moisture, and stream flow data for the study area. The risk analysis for drought duration and severity of three kinds of drought events were analyzed with univariate and three kinds of bivariate return periods based on the copula. Furthermore, the propagation of three kinds of drought was studied. From the investigation, it is observed that agricultural drought events are longer and more severe, besides the risk associated with agricultural drought is high compared to other kinds of drought. Moreover, the average time taken for meteorological drought to propagate into agricultural drought is 4.3 months and for the hydrological drought is 3.8 months for the river basin. The comprehensive study of three kinds of drought is helpful to adopt suitable drought management plans in the region. HIGHLIGHTS Studied characteristics of meteorological, agricultural, and hydrological drought events in the river basin.; Found out that agricultural drought events have a long duration and high severity.; Meteorological drought has less risk compared to the other two kinds of drought.; The propagation time to agricultural drought from meteorological drought is long compared to the time taken for hydrological drought events.

Study of tribological properties on Al/Al2O3/MoS2 hybrid composite processed by powder metallurgy

Aluminium ceramic composites with improved mechanical and chemical properties are essential and needed in aerospace and automotive application. The aluminium matrix composite reinforced with ceramic material of alumina (Al2O3) has good tribological properties. However, aluminium based ceramic composites require improvements in their lubrication properties. In this study an attempt is made in the development of a new material through powder metallurgy technique by the addition of molybdenum disulphide (MoS2), which acts as a solid lubricant. This molybdenum disulphide (MoS2) based solid lubricant has unique advantage that it can be used in vacuum space, but the same is not applicable in case of graphite. The microstructures, material combination, wear and friction properties were analysed by scanning electron microscopy, EDX, and pin-on-disc wear tester. The newly developed aluminium composite has significant improvements in tribological properties with a combination of 5% alumina (Al2O3) and 5% molybdenum disulphide (MoS2). The test reveals that sliding distance of 1000 m and sliding speed of 1.5 m/s with applied load of 5 N result in minimum wear loss of 0.0102 g and coefficient of friction as 0.117

Analysis of Various Road Pattern Recognition Methods for Satellite Images

Abstract--Recently road extraction from satellite imagery has emerged as one of the hot topics in the research field. It is particularly employed in the city planning, cartography and to revise already detected roads in Geographic Information Systems (GIS) environment.. Some of the several applications of road extraction are renewal of GIS database, reference for image registration, assistance for identification algorithms and fast mapping. Road extraction enables the road network to be truly presented in the object space when the image to ground systems transformation is carried out and it has been described as the method of detection and precise localization of roads in the image. Automatic road extraction attempts to simplify and speed up the road extraction process by focusing on automating all or few parts of this process. In photogrammetry and digital image processing fields, road extraction is considered as a challenging issue. In this paper detailed survey has been carried out on various road extraction techniques from satellite images and their performances were analyzed. Keywords-Particle filtering.kalman filtering, road extraction, Neural network and dense cloud points