Density Measurement in Oil and Gas Wells using Ultrasonic Sensors

, M.Sc. Thesis Sharif University of Technology Baneshi, Abdolkarim (Author) ; Movahedian Attar, Hamid (Supervisor)

Abstract

Production logging consists of running measurement instruments called logging tools into an oil or gas well to measure various parameters such as temperature, flow velocity, pressure, density, etc. The primary purpose for production logging is to allow enhancing production profits and decreasing costs. Nowadays the common way for fluid density measurement as a part of these tools depends on radioactive source. Special considerations must be taken upon the use of this principle due to its radioactive character. This thesis is focused on a non-radioactive method of determining density. The subject of this thesis is to consider methods for measuring density based on principle of acoustic...

Efficient Power Management of 3D-stacked DRAMs Through Aggressive Undervolting

, M.Sc. Thesis Sharif University of Technology Baneshi, Saeideh (Author) ; Sarbazi Azad, Hamid (Supervisor)

Abstract

Nowadays the performance of multi-core systems is increasing; however, the limited off-chip bandwidth of DRAMs is the biggest limiting factor for keeping up this trend. 3D stacked memories are good alternatives for current memories as they utilize high-bandwidth low-power through silicon via (TSV) connections. The main problem of these structures is significant rise of temperature as heat cannot be dissipated easily from the middle layers. As a result, utilizing thermal and power-aware management techniques is one of the most critical design goals of these systems. DRAM manufacturers consider timing parameters of memory controller conservatively high to guarantee the true functionality of...

On endurance of erasure codes in SSD-based storage systems

, Article Computer Architecture and Digital Systems (CADS), 17th CSI International Symposium on ; Article number 6714239 , 2013 , Pages 67-72 ; 9781479905621 Alinezhad Chamazcoti, S. (Saeideh) ; Miremadi, Gh. (Sayyed Ghassem) ; Asadi, H. (Hossein) ; Sharif Univesity of Technology

2013

Abstract

The wear-out of flash-based Solid-State Drives (SSDs) is a main concern that significantly affects their reliability. One major parameter that accelerates SSD wear-out is the number of write-cycles committed to flash chips. The number of write-cycles in SSD-based disk subsystem is highly dependent on the erasure code implemented in Redundant Array of Independent Disks (RAIDs). In this paper, we investigate the impact of erasure codes and the configuration of storage subsystems (i.e., the number of disks participated in the RAID array and stripe unit size) on the endurance of storage systems. The number of write-cycles is considered as a metric to evaluate the endurance of storage system. We...

Core–Shell nanophotocatalysts: review of materials and applications

, Article ACS Applied Nano Materials ; Volume 5, Issue 1 , 2022 , Pages 55-86 ; 25740970 (ISSN) Shafiee, A ; Rabiee, N ; Ahmadi, S ; Baneshi, M ; Khatami, M ; Iravani, S ; Varma, R. S ; Sharif University of Technology

American Chemical Society 2022

Abstract

Hybrid nanostructures and nanoarchitectures possess unique physicochemical properties such as high activity/functionality, enhanced physicochemical stability, and improved biocompatibility, which renders them suitable for various biomedical, pharmaceutical, environmental, and catalytic applications. In this context, core–shell nanophotocatalysts have shown superior activity compared to their counterparts, namely, their individual pristine semiconductors and composite materials components. Thus, the development of various innovative core–shell nanostructures as photocatalysts is of practical relevance in view of their unique properties with salient advantageous features applicable to, among...