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Determining the optimum heap height considering the irrigation rate and the slope of heap bed variations in miduk copper mine
, Article Acta Physica Polonica A ; Volume 128, Issue 2 , 2015 , Pages 352-354 ; 05874246 (ISSN) ; Rahimi, E ; Mohaghegh, N ; Sharif University of Technology
Polish Academy of Sciences
2015
Abstract
Determining an optimum height is remarked as one of the most important issues in heap designing and this is obtained by calculating the number and the height of heap lifts. Although the increase of lift height has benefits in heap leaching method from economic point of view, it will reduce the stability and make process problems such as low permeability. The current paper analyzes the effect of sulphuric acid irrigation on the strength parameters of Miduk oxide copper ores. In addition, the result of the process experiments have evaluated with different irrigation rates as well as variable conditions of permeability. From process view, approximately 75% of copper is recovered at irrigation...
Computer simulation of fluid motion in a porous bed using a volume of fluid method: Application in heap leaching
, Article Minerals Engineering ; Volume 19, Issue 10 , 2006 , Pages 1077-1083 ; 08926875 (ISSN) ; Jafari, A ; Yaghmaei, S ; Vossoughi, M ; Sarkomaa, P ; Sharif University of Technology
2006
Abstract
Heap leaching is a process extensively used by the mining industry to recover metals from low-grade ores and large quantities of submarginal material resources. Understanding flow through a packed particle bed is important to enhance the performance of heap leaching with respect to design and operating considerations. Complex fluid behavior in porous media, such as film flow, fragmentation, coalescence of droplets, and rivulet flow with or without meandering, has been widely observed in laboratory experiments. In this study, to provide detailed information of momentum and mass transfer phenomena in a granular bed direct numerical simulations (DNS) were performed. In this case the liquid-gas...
Leaching of a zinc ore and concentrate using the Geocoat™ technology
, Article Minerals Engineering ; Volume 24, Issue 1 , 2011 , Pages 64-69 ; 08926875 (ISSN) ; Petersen, J ; Roostaazad, R ; Hosseini, S ; Mohammad Mousavi, S ; Najafi, A ; Vasiri, A. K ; Sharif University of Technology
Abstract
In this study, the Geocoat™ technology was used for the extraction of zinc from a mineral concentrate obtained from the Kooshk mine (Yazd, Iran) by a culture dominated by the mesophilic bacterium Acidithiobacillus ferrooxidans in a packed column bioreactor. A low grade sphalerite ore was used as support for the concentrate coating. During the 100 days of leaching pH, Fe3+, Fetotal, microbial population density and zinc extraction were measured. The final zinc extraction from concentrate and low grade support was 97% and 78%, respectively, and it was found that leaching from the support does not proceed significantly before leaching from the coating is completed
A novel approach for avoiding wormhole attacks in VANET
, Article 1st South Central Asian Himalayas Regional IEEE/IFIP International Conference on Internet, AH-ICI 2009, 3 November 2009 through 5 November 2009, Kathmundu ; 2009 ; 9781424445707 (ISBN) ; Movaghar, A ; Mohammadizadeh, M ; Sharif University of Technology
Abstract
Different attacks on routing protocols in ad hoc networks occur that one of the most dangerous types is called wormhole attack. This attack happens with the assistance of at least two or more malicious nodes. In this attack nodes create a private tunnel which if a packet comes to one of them, it will be guided to other pair of these malicious nodes by this tunnel and that node broadcasts it into network. This action provides a short connection in the network that is controlled by these malicious nodes. Hence they control all Packets that come to them and threaten the security of data within packets or delete them. Totally, what a wormhole does is an incorrect understanding of network...
A novel approach for avoiding wormhole attacks in VANET
, Article 2nd International Workshop on Computer Science and Engineering, WCSE 2009, 28 October 2009 through 30 October 2009 ; Volume 2 , 2009 , Pages 160-165 ; 9780769538815 (ISBN) ; Movaghar, A ; Mohammadizadeh, M ; Sharif University of Technology
Abstract
Different attacks on routing protocols in ad hoc networks occur that one of the most dangerous types is called wormhole attack. This attack happens with the assistance of at least two or more malicious nodes. In this attack nodes create a private tunnel which if a packet comes to one of them, it will be guided to other pair of these malicious nodes by this tunnel and that node broadcasts it into network. This action provides a short connection in the network that is controlled by these malicious nodes. Hence they control all Packets that come to them and threaten the security of data within packets or delete them. Totally, what a wormhole does is an incorrect understanding of network...
SEAODV: Secure efficient AODV routing protocol for MANETs networks
, Article ACM International Conference Proceeding Series, 24 November 2009 through 26 November 2009, Seoul ; Volume 403 , 2009 , Pages 940-944 ; 9781605587103 (ISBN) ; Movaghar, A ; Safi, S. M ; Sharif University of Technology
Abstract
Secure routing is one of the most important topics in the wireless MANETs networks. MANETs networks don't have a central infrastructure for the management of routing in the networks. Each node independently routes and sends packets, so many attacks such as forging, modifying, and denial of service (DoS), Occur in these networks. In this paper, we present the new protocol, SEAODV; Secure Efficient Ad-hoc on Demand Routing Protocol for MANETs networks. SEAODV is based on the AODV algorithm and in comparison with existing secure AODV protocols such as SAODV, ARAN and SEAR have improved security and performances. SEAODV uses HEAP authentication Scheme with symmetric cryptography and one-way hash...