Suzana Lutovac

Evaluation of Underground Zinc Mine Investment Based on Fuzzy-Interval Grey System Theory and Geometric Brownian Motion

Underground mine projects are often associated with diverse sources of uncertainties. Having the ability to plan for these uncertainties plays a key role in the process of project evaluation and is increasingly recognized as critical to mining project success. To make the best decision, based on the information available, it is necessary to develop an adequate model incorporating the uncertainty of the input parameters. The model is developed on the basis of full discounted cash flow analysis of an underground zinc mine project. The relationships between input variables and economic outcomes are complex and often nonlinear. Fuzzy-interval grey system theory is used to forecast zinc metal prices while geometric Brownian motion is used to forecast operating costs over the time frame of the project. To quantify the uncertainty in the parameters within a project, such as capital investment, ore grade, mill recovery, metal content of concentrate, and discount rate, we have applied the concept of interval numbers. The final decision related to project acceptance is based on the net present value of the cash flows generated by the simulation over the time project horizon.

Analysis of blasting impacts at the open pit Manastiriste near Topola on the monastery complex

This paper discusses the problems associated with the negative effects that accompany blasting operations, and the certain conclusions were derived. One of the negative effects of blasting operations is the phenomenon of seismic action and its effects on the buildings and the environment. Shock waves, induced by blasting, could cause damages to the building facilities and the environment. Those shocks seem to be very unfavorable to both humans and the environment. Therefore, certain standards were developed that define permissible values of impacts on buildings and people in buildings. In Serbia, there are no standards for assessing the impact of such shock waves. The international regulations and standards, mostly Russian and German, will be used to solve this problem. This case study provides an overview the measurement of shock waves during blasting at the open pit Manastiriste near Topola in a function of the quantity of used explosives, their impact on the surrounding buildings with special reference to the Monastery of the Holy Archangel Michael, as well as the assessment of measurement results according to the appropriate scales in the world. Keywords blasting, shock waves, measurement, impact, seismics * University of Belgrade, Faculty of Mining and Geology, Djusina 7, 11000 Belgrade, Serbia, e-mail: sanjabajic@sezampro.com; radmila.gacina@rgf.rs; katarina.urosevic@rgf.rs; suzana.lutovac@rgf.bg.ac.rs

Determination of Safe Distance While Blasting at Open Pit Mine Zabrdica, Valjevo

This paper deals with problems related to the determination of safe distance with special reference to adverse effects accompanying blast work. One of them is related to the seismic effect caused by blast work. Therefore measurements have been carried out at the open pit mine Zabrdica-Valjevo which served to determine the law of soil oscillation. On the basis of carried out seismic measurements and the analysis of oscillation velocity, the law of soil oscillation was determined according to the formula of M.A. Sadovski.

Justification of renewed coal exploitation from the deposit 'Bajovac'

Coal presents the basic energy potential of the Republic of Serbia. More than half of electric energy production in our country comes from this resource. This causes a need for activation the new seams of raw material which are potentially exploitable. This work presents an extract from the research results, published within the Project TR 33029 “Study of Possibilities for Valorization the Remaining Coal Reserves with a View to Provide the Stability of Energy Sector of the Republic of Serbia”, financed by the Ministry of Education and Science. This work treated the problems of future coal exploitation from the West Morava Basin, with special review to the activation of the closed mine “Bajovac”.