Sharif Digital Repository

Storage subsystem is one of the most important components of a computer system. As more valuable information such as bank transactions are being stored in storage subsystems,occurrence of an unrecoverable error can lead to a much bigger problem. A storage subsystem can be divided into software and hardware part. Previous works focused on fault injection in the higher layers of the storage stack and didn’t consider fault injection at the device driver level. In this thesis, the dependability of storage stack is evaluated using fault injection at the device driver layer. Various hardware and software faults that can occur in hard disks and solid state drives are studied and dependability of... 

LOOP accident is one of the most important accidents in NPPS and it leads to loss of power supply of the RCP pumps which are the main pumps of primary circuit. Subsequently trip of the rector occurs. In safety analysis, concerning worst conditions, assumes that after a small period of time, main generator of plant stops working and loss of AC power supply of all power plant loads including safety systems ocures. To control of this accident, it’s necessary to startup and load backup power supply system (EDGs) for at least one safety channels, if not, the accident moves forwards and becomes S.B.O accident which is more important accident that ends to core damage because of stops working of all... 

Nowadays the concept of competition in business has been expanded from enterprises to supply chains. For success in this competitive environment, it should be established complete coordination and synchronization between different rings of the chain in both strategy and operations. The supply chain management is a factor for achieving to this purpose. Effective supply chain management, especially in complex supply chains like petroleum upstream supply chain, requires to strategic factors that propel the chain to the long term goals. Unfortunately, it is showing off the vacancy of attending to this case in the literature. This thesis tries to fill this gap in literature with a new approach... 

Composite systems consisting of concrete columns and steel beams are introduces as structural systems in recent years. These structural systems enjoy merits of both steel and concrete frames by efficiently combining the advantages of them. This study is allocated to lateral force resistance system using armed concrete and structural steel. Advantages of composite structures rather to those of two other conventional ones are among performance characteristics under ultimate loads, economical conservation, and higher speed of construction.In this research the aim is to study these frame under earthquake induced loads. The seismic performances of these composite frames with through column beams,... 

In this study, the hierarchical multiscale method is presented to model macro-scale materials with considering large and plastic deformations. Since the classic methods such as continuum mechanics were unable to model defects such as dislocations, voids, and etc. at nano scale. Also, the molecular dynamics methods have high computational costs; hence, recearchers try to develop multiscale methods in order to utilize them. Multiscale modeling in which two scales are considered and some information be transferred from fine scale to coarse scale. In this work, the coarse scale is modeled by finite element method (FEM) and the fine scale is analysed by molecular dynamics (MD). In fact, two...