Synopsis The regression effect in ore-reserve estimation has been identified, described and quantified in vein and reef deposits for more than twenty years. Its importance in ‘three-dimensional’ deposits whether underground or open-pit -has been recognized under the alternate guise of the geostatistical volume-variance relationship. The Fontainebleau school has developed the technique of disjun...

One of the most effective parameters in economics of open-pit mines is the pit slope angle, so that the slope angle more than the optimum value increases the probability of a large failure in the pit wall and the slope angle less than the optimum value leads to increasing stripping ratio and reducing net present value of mine. Therefore, in this paper, considering the limit equilibrium methods ...

Transportation costs are a significant part of capital and operating costs of large open pit mines. Cost efficiency and high reliability of in pit crushing and conveying systems compared to conventional truck-shovel system makes it more appealing to be utilized in modern mining activities. In this paper the suitable location of an in pit crusher is investigated as a single hub location problem....

Background: Sacral pit is a shallow or deep dimple in the lower sacral region, with a reported prevalence of 3-5% among newborns. The aim of the present study was to investigate spinal cord abnormalities in newborns with sacral pit via ultrasound examinations. Methods: In this descriptive study, 3071 infants born at 34-42 weeks of gestation were studied in hospitals affiliated to Islamic Azad U...

In open-pit mine planning, the design of the most profitable ultimate pit limit is a prerequisite to developing a feasible mining sequence. Currently, the design of an ultimate pit is achieved through a computer program in most mining companies. The extraction of minerals in open mining methods needs a lot of capital investment, which may take several decades. Before the extraction, the p...