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    A particle swarm optimization approach for robust unit commitment with significant vehicle to grid penetration

    , Article Iranian Conference on Intelligent Systems, ICIS 2014 ; 2014 Kherameh, A. E ; Aien, M ; Rashidinejad, M ; Fotuhi-Firouzabad, M
    Abstract
    Smartening of contemporaneous power delivery systems in conjunction with increased penetration of vehicle to grid (V2G) technology, changes the way market participants play their role in the market operation to maximize their profit. In V2G technology, plug-in electric vehicles (PEV) have bidirectional power flows i.e. they can either inject power to the grid or draw power from it. In recent years, the V2G technology has found a world wild attention due to its important advantages such as the peak load reduction and providing system reserve, to name a few. The unit commitment (UC) is a power system operation problem which is used to find the optimal operation schedule of generation units.... 

    Assessment of an optimized combination of Iranian power plants by environmental costs impact of carbon tax and fossil fuel price on longterm development of iranian electricity supply system

    , Article Journal of Environmental Studies ; Vol. 40, issue. 2 , 2014 , p. 415-430 Manzoor, D ; Farmad, M ; Aryanpur, V ; Shafiei, E ; Sharif University of Technology
    Abstract
    Despite the abundant renewable energy sources, the Iranian energy sector relies almost entirely on fossil fuel energy resources. Power sector is dominant source of CO2 emissions and responsible for about 35% of total CO2 emissions in the country. Additionally, long-term electricity demand of Iran is expected to grow quickly, which in turn requires extensive investment to meet the growing demand over the next decades. On the other hand, increasing domestic fossil fuel consumption had been a serious challenge due to high costs of oil and gas. Current study pays particular attention to the possible penetration rates of renewable electricity technologies and their implications for fossil fuel... 

    Design of multilevel interconnect network of an ASIC macrocell for 7.5nm technology node using carbon based interconnects

    , Article 2014 IEEE International Interconnect Technology Conference / Advanced Metallization Conference, IITC/AMC 2014 ; May , 2014 , p. 163-166 Farahani, E. K ; Sarvari, R ; Sharif University of Technology
    Abstract
    Multilevel interconnect network of a macrocell for 7.5 nm technology node is designed with carbon based interconnects (CBI) and Cu. Results are compared. Constrains of using CBI is discussed. It is shown that by using CBI power dissipation associated with wires could decrease by 32%. To use GNRs for more than one metal pair, reverse wire pitch idea is proposed that prevents undesirable increase in the number of metal layers  

    All-optical wavelength-routed architecture for a power-efficient network on chip

    , Article IEEE Transactions on Computers ; Vol. 63, issue. 3 , 2014 , p. 777-792 Koohi, S ; Hessabi, S ; Sharif University of Technology
    Abstract
    In this paper, we propose a new architecture for nanophotonic Networks on Chip (NoC), named 2D-HERT, which consists of optical data and control planes. The proposed data plane is built upon a new topology and all-optical switches that passively route optical data streams based on their wavelengths. Utilizing wavelength routing method, the proposed deterministic routing algorithm, and Wavelength Division Multiplexing (WDM) technique, the proposed data plane eliminates the need for optical resource reservation at the intermediate nodes. For resolving end-point contention, we propose an all-optical request-grant arbitration architecture which reduces optical losses compared to the alternative... 

    Dissipative quantum metrology in manybody systems of identical particles

    , Article New Journal of Physics ; Vol. 16, issue , January , 2014 Benatti, F ; Alipour, S ; Rezakhani, A. T ; Sharif University of Technology
    Abstract
    Estimation of physical parameters is essential in almost any part of science and technology. The enhancement of performance in this task (e.g. beating the standard classical shot-noise limit) using available physical resources is a major goal in metrology. Quantum metrology in closed systems has indicated that entanglement in such systems may be a useful resource. However, whether in open quantum systems such enhancements may still show up is not yet fully understood. Here, we consider a dissipative (open) quantum system of identical particles in which a parameter of the open dynamics itself is to be estimated. We employ a recently developed dissipative quantum metrology framework, and... 

    Privacy analysis and improvements of two recent RFID authentication protocols

    , Article 11th International ISC Conference on Information Security and Cryptology, ISCISC 2014 ; 3-4 September , 2014 , pp. 137-142 ; ISBN: 9781479953837 Baghery, K ; Abdolmaleki, B ; Akhbari, B ; Aref, M. R ; Sharif University of Technology
    Abstract
    Radio Frequency Identification (RFID) technology is being deployed at our daily life. Although RFID systems provide useful services to users, they can also threat the privacy and security of the end-users. In order to provide privacy and security for RFID users, different RFID authentication protocols have been proposed. In this study, we investigate the privacy of two recently proposed RFID authentication protocols. It is shown that these protocols have some privacy problems that cannot provide user privacy. Then, in order to enhance the privacy of these protocols, two improvements of analyzed protocols are proposed that provide RFID users privacy  

    On non-progressive spread of influence through social networks

    , Article Theoretical Computer Science ; Vol. 550, issue. C , 2014 , pp. 36-50 ; ISSN: 03043975 Fazli, M. A ; Ghodsi, M ; Habibi, J ; Jalaly, P ; Mirrokni, V ; Sadeghian, S ; Sharif University of Technology
    Abstract
    The spread of influence in social networks is studied in two main categories: progressive models and non-progressive models (see, e.g., the seminal work of Kempe et al. [8]). While the progressive models are suitable for modeling the spread of influence in monopolistic settings, non-progressive models are more appropriate for non-monopolistic settings, e.g., modeling diffusion of two competing technologies over a social network. Despite the extensive work on progressive models, non-progressive models have not been considered as much. In this paper, we study the spread of influence in the non-progressive model under the strict majority threshold: given a graph G with a set of initially... 

    A power-efficient reconfigurable architecture using PCM configuration technology

    , Article Proceedings -Design, Automation and Test in Europe, DATE ; 2014 Ahari, A ; Asadi, H ; Khaleghi, B ; Tahoori, M. B ; Sharif University of Technology
    Abstract
    Promising advantages offered by resistive NonVolatile Memories (NVMs) have brought great attention to replace existing volatile memory technologies. While NVMs were primarily studied to be used in the memory hierarchy, they can also provide benefits in Field-Programmable Gate Arrays (FPGAs). One major limitation of employing NVMs in FPGAs is significant power and area overheads imposed by the Peripheral Circuitry (PC) of NVM configuration bits. In this paper, we investigate the applicability of different NVM technologies for configuration bits of FPGAs and propose a power-efficient reconfigurable architecture based on Phase Change Memory (PCM). The proposed PCM-based architecture has been... 

    A subthreshold symmetric SRAM cell with high read stability

    , Article IEEE Transactions on Circuits and Systems II: Express Briefs ; Vol. 61, issue. 1 , Jan , 2014 , p. 26-30 ; 15497747 Saeidi, R ; Sharifkhani, M ; Hajsadeghi, K ; Sharif University of Technology
    Abstract
    This brief introduces a differential eight-transistor static random access memory (SRAM) cell for subthreshold SRAM applications. The symmetric topology offers a smaller area overhead compared with other symmetric cells for the same stability in the read operation. Two transistors isolate the cell storage nodes from the read operation path to maintain the data stability of the cell. This topology improves the data stability at the expense of read operation delay. Thorough postlayout Monte Carlo worst corner simulations in 45-nm CMOS technology are conducted. The proposed cell operates down to 0.35 V with a read noise margin of 74 mV and a write noise margin of 92 mV. Under this condition,... 

    12 bits, 40MS/s, low power pipelined SAR ADC

    , Article Midwest Symposium on Circuits and Systems ; Aug , 2014 , p. 841-844 Khojasteh Lazarjan, V ; Hajsadeghi, K ; Sharif University of Technology
    Abstract
    This paper presents a low power SAR ADC utilizing pipelining to increase the resolution up to 12 bits while maintaining a high speed sampling rate. Novel system level modifications and also new comparator architecture are proposed to optimize the power consumption. The ADC is designed and simulated in 0.18um CMOS technology by 1.2v supply voltage consuming 4.5mW power at 40MS/s sampling rate. The results indicates an effective number of bits (ENOB) of 11.04 bit and a challenging FOM of 54.9 fj/conversion which verifies the competence of proposed method  

    A novel approach towards control of exoskeletal systems as an assistive device for human's upper extremity

    , Article JICTEE 2014 - 4th Joint International Conference on Information and Communication Technology, Electronic and Electrical Engineering ; 2014 Ghassemi, M ; Jahed, M ; Sharif University of Technology
    Abstract
    With increasing importance of exoskeletons as rehabilitation apparatuses, suitable and delicate control strategies has received much attention. In order to control the exoskeleton, there should be a complete understanding of torques produced by the limb itself which makes the musculoskeletal modeling of the limb essential but also complex. In addition, the musculoskeletal model can be used to discover the user's desired movement to control the exoskeleton. In this paper a complete musculoskeletal model for the elbow with two degrees of freedom is developed and simulated. Next the model is used to determine user's desired movement. Finally based on this evaluation, an exoskeleton model is... 

    Ultra-sensitive detection of leukemia by graphene

    , Article Nanoscale ; Vol. 6, issue. 24 , Dec , 2014 , p. 14810-14819 Akhavan, O ; Ghaderi, E ; Hashemi, E ; Rahighi, R ; Sharif Universit of Technology
    Abstract
    Graphene oxide nanoplatelets (GONPs) with extremely sharp edges (lateral dimensions ∼20-200 nm and thicknesses <2 nm) were applied in extraction of the overexpressed guanine synthesized in the cytoplasm of leukemia cells. The blood serums containing the extracted guanine were used in differential pulse voltammetry (DPV) with reduced graphene oxide nanowall (rGONW) electrodes to develop fast and ultra-sensitive electrochemical detection of leukemia cells at leukemia fractions (LFs) of ∼10-11 (as the lower detection limit). The stability of the DPV signals obtained by oxidation of the extracted guanine on the rGONWs was studied after 20 cycles. Without the guanine extraction, the DPV peaks... 

    Two-compartment processing as a tool to boost recombinant protein production

    , Article Engineering in Life Sciences ; Vol. 14, issue. 2 , March , 2014 , p. 118-128 Jazini, M ; Herwig, C ; Sharif University of Technology
    Abstract
    Pichia pastoris is used extensively as a production platform for many recombinant proteins. The dissolved oxygen (DO) is one of the most important factors influencing protein production. The influence of the DO on productivity has not been studied independent from the feed rate. In this work, various DO levels were investigated independent from the feed rate. The model system was recombinant P. pastoris under the control of methanol-induced alcohol oxidase promoter, which expressed HRP as the target protein. No significant effect was observed in terms of titer and specific productivity, which is a confirmation of the fact that the DO in a one-compartment system cannot boost productivity for... 

    Application of sol-gel based molecularly imprinted xerogel for on-line capillary microextraction of fentanyl from urine and plasma samples

    , Article Analytical Methods ; Volume 5, Issue 24 , 2013 , Pages 7096-7101 ; 17599660 (ISSN) Bagheri, H ; Piri-Moghadam, H ; Bayat, P ; Balalaie, S ; Sharif University of Technology
    2013
    Abstract
    A molecularly imprinted xerogel (MIX) for fentanyl was successfully prepared on the inner surface of a copper tube by sol-gel technology. Primarily, the tube was treated by self-assembly monolayers of 3-(mercaptopropyl) trimethoxysilane and then [3-(2,3-epoxypropoxy)-propyl]-trimethoxysilane was employed as a precursor for imprinting the template molecule in acidic conditions. During the sol-gel process influential parameters including volume and concentration of fentanyl were carefully investigated to obtain the most efficient and appropriate xerogel. In parallel, a non-imprinted xerogel (NIX) was synthesized in the absence of fentanyl. The extraction efficiencies achieved from MIX and NIX,... 

    A web-based methodology for convergent product fuzzy networks using the Steiner tree

    , Article Journal of Industrial and Production Engineering ; Volume 30, Issue 7 , 2013 , Pages 415-432 ; 21681015 (ISSN) Hassanzadeh, R ; Mahdavi, I ; Mahdavi Amiri, N ; Sharif University of Technology
    2013
    Abstract
    An important manufacturing technology spectrum is to consider rapid and sensitive assemblies through convergent product (CP) in digital environment. We integrate functions and sub-functions using a comprehensive mathematical optimization process. To form the CP, a web-based fuzzy network is considered in which a collection of base functions and sub-functions configure the nodes and each arc in the network is to be a link between two nodes. The aim is to find an optimal tree of functionalities in the network adding value to the product in the web environment. First, a purification process is performed in the product network to assign the links among bases and sub-functions. Then, fuzzy... 

    Quantum metrology in open systems: Dissipative cramer-rao bound

    , Article Physical Review Letters ; Volume 112, Issue 12 , 2014 ; 00319007 (ISSN) Alipour, S ; Mehboudi, M ; Rezakhani, A. T ; Sharif University of Technology
    American Physical Society  2014
    Abstract
    Estimation of parameters is a pivotal task throughout science and technology. The quantum Cramér-Rao bound provides a fundamental limit of precision allowed to be achieved under quantum theory. For closed quantum systems, it has been shown how the estimation precision depends on the underlying dynamics. Here, we propose a general formulation for metrology scenarios in open quantum systems, aiming to relate the precision more directly to properties of the underlying dynamics. This feature may be employed to enhance an estimation precision, e.g., by quantum control techniques. Specifically, we derive a Cramér-Rao bound for a fairly large class of open system dynamics, which is governed by a... 

    Grafting the sol-gel based sorbents by diazonium salts: A novel approach toward unbreakable capillary microextraction

    , Article Journal of Chromatography A ; Volume 1318 , November , 2013 , Pages 58-64 ; 00219673 (ISSN) Bagheri, H ; Bayat, P ; Piri Moghadam, H ; Sharif University of Technology
    2013
    Abstract
    The present work deals with a novel approach for grafting a sol-gel based sorbent, using diazonium salts for preparation of an unbreakable capillary microextraction (CME) device in on-line combination with high performance liquid chromatography (HPLC). The use of diazonium salts modifier allowed all types of metallic and non-metallic substrates to be used without any limitation. Substrates including copper, brass, stainless steel and polytetrafluoroethylene (PTFE) were chosen to be functionalized by chemical or electrochemical reduction of 4-amino phenyl acetic acid. Then, 3-(trimethoxysilyl)propylamine (3TMSPA) was selected as the precursor and the only reagent for preparation of the... 

    Proposing a hybrid protocol for secure wireless networks based on signcryption scheme

    , Article 2013 World Congress on Computer and Information Technology, WCCIT 2013 ; June , 2013 , Page(s): 1 - 6 ; 9781479904600 (ISBN) Darmian, N. R ; Oskoei, H. R. D ; Vazirnezhad, B ; Sharif University of Technology
    2013
    Abstract
    Considering the weaknesses of cryptography algorithms and the attacks performed against them, cryptography alone cannot guarantee the security of communication in a wireless network. With regard to the developments in wireless communication networks brought about by smart array antennas, security can be sought in the physical layer as well, aiming to restrict the access of the data in a wireless network and limit it to authorized users only in order to further restrain malicious data accesses. In this paper, we analysis a strategy for restricting data access using smart array antennas and present the results in security by a parameter called exposure region. For this strategy afterwards we... 

    On tuning FO[PI] controllers for FOPDT processes

    , Article Electronics Letters ; Volume 49, Issue 21 , 2013 , Pages 1326-1328 ; 00135194 (ISSN) Badri, V ; Tavazoei, M. S ; Sharif University of Technology
    2013
    Abstract
    A method recently proposed for tuning fractional order [proportional integral] (FO[PI]) controllers is investigated. This tuning method, when applied in control of first-order plus dead time (FOPDT) processes, can ensure the desired phase margin, the desired gain crossover frequency and the flatness of the phase Bode plot at such a frequency. The necessary and sufficient condition for the applicability of the aforementioned tuning method is derived. Also, it is shown that this condition can be used in obtaining the achievable performance region of the tuning method in the gain crossover frequency-phase margin plane  

    A branch-and-bound algorithm for the single machine sequence-dependent group scheduling problem with earliness and tardiness penalties

    , Article Applied Mathematical Modelling ; 2015 ; 0307904X (ISSN) Keshavarz, T ; Savelsbergh, M ; Salmasi, N ; Sharif University of Technology
    2015
    Abstract
    The NP-hard single machine sequence-dependent group scheduling problem with minimization of total weighted earliness and tardiness is investigated. An arc-time-indexed formulation is presented and a Lagrangian-based branch-and-bound algorithm is proposed. The Lagrangian relaxation of the arc-time-indexed formulation is solved as a shortest path problem. The results of an extensive computational study demonstrate the efficacy of the proposed algorithm and establish characteristics of some hard to solve instances