1. introduction mountain regions are increasingly endangered by a variety of disaster, including avalanche, debris flows, and rock slide. some characteristics such as elevation, angle of slope, vegetation and climatic elements could affect the avalanche event. indeed, avalanche is the second factor in soil erosion that causes demolition; therefore, it threatens the food safety. iran has two mai...

in this study the land surface in western half of hyper-arid lut desert, in south east of iran, which is covered by yardangs, a worldwide typical landform for aeolian erosion, were classified by self organizing maps (som) method. in the first step by using digital elevation model with 10 m resolution and matlab software, 22 morphometric parameters were calculated based on derivative of the surf...

We prove that the total curvature of any planar graph with nonnegative combinatorial is an integral multiple 1 12 \frac {1}{12} </mml:se...

abstract limitations of traditional (conventional) soil surveys and improvement of information technology have lead soil surveyors to invent new methods which are generally called digital soil mapping (dsm). the aim of these methods is the prediction of soil classes or soil properties based on easily-available or measuring environmental variables. the objective of this investigation is to study...