Constrained long-term production scheduling problem(CLTPSP) of open pit mines has been extensively studied in the past few decades due to its wide application in mining projects and the computational challenges it pos...Constrained long-term production scheduling problem(CLTPSP) of open pit mines has been extensively studied in the past few decades due to its wide application in mining projects and the computational challenges it poses become an NP-hard problem.This problem has major practical significance because the effectiveness of the schedules obtained has strong economical impact for any mining project.Despite of the rapid theoretical and technical advances in this field,heuristics is still the only viable approach for large scale industrial applications.This work presents an approach combining genetic algorithms(GAs) and Lagrangian relaxation(LR) to optimally determine the CLTPSP of open pit mines.GAs are stochastic,parallel search algorithms based on the natural selection and the process of evolution.LR method is known for handling large-scale separable problems; however,the convergence to the optimal solution can be slow.The proposed Lagrangian relaxation and genetic algorithms(LR-GAs) combines genetic algorithms into Lagrangian relaxation method to update the Lagrangian multipliers.This approach leads to improve the performance of Lagrangian relaxation method in solving CLTPSP.Numerical results demonstrate that the LR method using GAs to improve its performance speeding up the convergence.Subsequently,highly near-optimal solution to the CLTPSP can be achieved by the LR-GAs.展开更多
According to the particularity of the open pit, the main influencing factors of mining quantity about mineral resources have been summarized systematically in life cycle and the structured hierarchical relation of its...According to the particularity of the open pit, the main influencing factors of mining quantity about mineral resources have been summarized systematically in life cycle and the structured hierarchical relation of its influencing factors has been constructed. In the light of the production process of open pit, the functional relationships between investment, mining cost and mining quantity have been defined based on the process of mining and loading so that the relation of the life cycle cost and mining quantity can be set up. And what’s more, in order to obtain the maximum economic profit of mining enterprises in life cycle, the planning model of mining quantity has been established based on the life cycle cost. The rational distribution of mining quantity will have been found on the condition of obtaining optimal solution about the planning model so as to determine scientifically the production scale of mining enterprises from the point of view of the sustainable development.展开更多
The measured data of vibrations induced by excavation of deep-buried cavern and open pit with method of bench blasting were analyzed by Fourier Transform and Wavelet Transform,and the characteristics of vibrations ind...The measured data of vibrations induced by excavation of deep-buried cavern and open pit with method of bench blasting were analyzed by Fourier Transform and Wavelet Transform,and the characteristics of vibrations induced under these two circumstances were studied.It is concluded that with the similar rock condition and drilling-blasting parameters,vibration induced by bench blasting in deep-buried cavern has a higher main frequency and more scattered energy distribution than that in open pit.The vibration induced by bench blasting in open pit is mainly originated from the blast load,while the vibration induced by bench blasting in deep-buried cavern is the superposition of vibrations induced by blast load and transient release of in-situ stress.The vibration induced by transient release of in-situ stress increases with the stress level.展开更多
文摘Constrained long-term production scheduling problem(CLTPSP) of open pit mines has been extensively studied in the past few decades due to its wide application in mining projects and the computational challenges it poses become an NP-hard problem.This problem has major practical significance because the effectiveness of the schedules obtained has strong economical impact for any mining project.Despite of the rapid theoretical and technical advances in this field,heuristics is still the only viable approach for large scale industrial applications.This work presents an approach combining genetic algorithms(GAs) and Lagrangian relaxation(LR) to optimally determine the CLTPSP of open pit mines.GAs are stochastic,parallel search algorithms based on the natural selection and the process of evolution.LR method is known for handling large-scale separable problems; however,the convergence to the optimal solution can be slow.The proposed Lagrangian relaxation and genetic algorithms(LR-GAs) combines genetic algorithms into Lagrangian relaxation method to update the Lagrangian multipliers.This approach leads to improve the performance of Lagrangian relaxation method in solving CLTPSP.Numerical results demonstrate that the LR method using GAs to improve its performance speeding up the convergence.Subsequently,highly near-optimal solution to the CLTPSP can be achieved by the LR-GAs.
文摘According to the particularity of the open pit, the main influencing factors of mining quantity about mineral resources have been summarized systematically in life cycle and the structured hierarchical relation of its influencing factors has been constructed. In the light of the production process of open pit, the functional relationships between investment, mining cost and mining quantity have been defined based on the process of mining and loading so that the relation of the life cycle cost and mining quantity can be set up. And what’s more, in order to obtain the maximum economic profit of mining enterprises in life cycle, the planning model of mining quantity has been established based on the life cycle cost. The rational distribution of mining quantity will have been found on the condition of obtaining optimal solution about the planning model so as to determine scientifically the production scale of mining enterprises from the point of view of the sustainable development.
基金Project(2010CB732003) supported by the National Basic Research Program of ChinaProjects(50725931,50779050 and 50909077) supported by the National Natural Science Foundation of China
文摘The measured data of vibrations induced by excavation of deep-buried cavern and open pit with method of bench blasting were analyzed by Fourier Transform and Wavelet Transform,and the characteristics of vibrations induced under these two circumstances were studied.It is concluded that with the similar rock condition and drilling-blasting parameters,vibration induced by bench blasting in deep-buried cavern has a higher main frequency and more scattered energy distribution than that in open pit.The vibration induced by bench blasting in open pit is mainly originated from the blast load,while the vibration induced by bench blasting in deep-buried cavern is the superposition of vibrations induced by blast load and transient release of in-situ stress.The vibration induced by transient release of in-situ stress increases with the stress level.
