استفاده از تصمیم گیری خوشه بندی خاکستری در تعیین حد روباز معدن کاوی The Application of Grey Clustering Decision in Determining the Rational Open-pit Limit of Mining

I. INTRODUCTION LONG with the rapid development of computer technology and the application in various realms of sciences, the basic industry also has experienced fierce technological changes. In recent years, the computer and the automated technology already seeped in the mining industry [1]. However, we find that many problems of the mining engineering usually involve a lot of experience and analysis for uncertainties. Until now, the mining computation could not propose the persuasive quantitative relations for decision-making. This is because the mining geological conditions are complex, and production process and techniques are changeable. The existing mathematics and mechanics methods in solving mining problems are also imperfect [2]. So far, the understandings of mining rules and solutions for production problems mainly rely on project analogism without any direction of scientific theories. This is the fundamental reason leading to the lag in mining technology and hindering the development of mining industry. As a new front-line science, the research on gray system has made progress in many aspects. Regardless of the fact that grey system is complex, fuzzy and nonstandard, the method applied is the Week Method. Whining using this method, the request for given information is weak; such information could be incomplete, qualitative and fuzzy. The more alternatives are considered when making a decision, the more prominent is grey system theory[3]. Research on the grey system theory and its application in mining industry, especially the application of grey decision-making in proposing mine, has shown great academic and practical significance. II. THE KEY PROBLEM Since long ago, the design of reasonable open-pit limits mainly depends on manual work. By analogy or borrowing ideas from the existing information and experience, the actual alternatives are limited. It’s very hard to define applicable standards for the appropriate open-pit limits. Under this circumstance, designers’ experiences play decisive role. So such a traditional method based on experience to define the mining limit is inaccurate; furthermore, since in the designing stage, designers only conduct some qualitative investigation and superficial quantitative computation, they can not prove whether the proposals are reasonable, without mentioning which proposal is optimal. Regarding mining in installments, in order to ensure the sustainable mining, based on the present technical and economical conditions, the most important work is to determine the reasonable open-pit limits. Usually, we apply parametric function method to obtain many alternatives. However, when considering the effective factors, such as quantity of underground ore, grade of the underground ore, quantity of rock, the ratio of rock’s and high grade ore’s quantity and the total benefit, it’s hard to determine the reasonable open-pit limits by applying the existing decision-making techniques. By now, finding a reasonable and feasible decision-making technique becomes the key factor in determining the open-pit limits. V. CONCLUSION This paper applies the basic principles of grey decision-making theory and grey clustering decision-making theory, makes grey clustering decisions for the open-pit limits obtained through parametric function and gets the optimal and feasible proposals for mining in installments. In order to make sure that the open-pit limits are reasonable, this paper applies multi mining limit proposals, discusses the influencing factors — quantity of milling in ore, grade of milling in ore, quantity of rock (including quantity of not milling in ore (low grade ore) and rock), the ratio of rock’s and milling in ore’s quantity, the total benefit, and provides new decision-making train of thought and methods when determining the reasonable open-pit limits.