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    MASTER: Reclamation of hybrid scratchpad memory to maximize energy saving in multi-core edge systems

    , Article IEEE Transactions on Sustainable Computing ; 2021 ; 23773782 (ISSN) Shekarisaz, M ; Hoseinghorban, A ; Bazzaz, M ; Salehi, M ; Ejlali, A ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2021
    Abstract
    Most modern multi-core edge devices work in outdoor situations with limited power supplies like energy harvester and batteries. Therefore, energy consumption is a fundamental issue in which the memory subsystem has a significant role. Scratchpad memories (SPM) can provide a broad potential for energy saving. Still, due to the insufficient SPM capacity in such edge devices, a rigorous SPM data allocation scheme is necessary to reduce the energy consumption of the memory subsystem. Emerging non-volatile memories (NVMs) are very useful to reduce the energy consumption of the memory subsystem. Therefore, embedded and edge devices can take advantage of hybrid SPM composed of both NVM and SRAM to... 

    Design and Implement of Voltage Ripple Measuring System for Power Supply of Microwave Tubes

    , M.Sc. Thesis Sharif University of Technology Ahmadi Someh, Saeed (Author) ; Kaboli, Shahryar (Supervisor)
    Abstract
    Mostly, the high voltage DC power supplies have output voltage ripple. In such an applications like power supply of microwave lamps in radar systems, low output voltage ripple is an important point of operational characteristics. On the other hand, measuring the low voltage ripple will be a challenge that can lead to recognize of its reasons and reduce its amplitude. In this thesis, different ways of ripple measurement constraints is described, then a method based on high pass filters for output voltage ripple measurement is implemented. The impact of components tolerance and their parasitic components like shunt parasitic resistance of a capacitor in filter operational characteristics is... 

    Hardware Design for Cold Plasma Characterization Chamber

    , M.Sc. Thesis Sharif University of Technology Aghapour, Reza (Author) ; Rashidian, Bijan (Supervisor) ; Faez, Rahim (Supervisor)
    Abstract
    Cold plasma due to its special properties has many applications in the microelectronics industry. At the beginning of this study, a few examples of widely used plasmas and the requirements for driving their power sources have been investigated. To generate and characterize plasma, various topologies of DC power supply construction, including high-voltage low-current power supplies called multipliers and low-voltage high-voltage power supplies called converters, have been reviewed and compared.Circuit for pulse generating for plasma application has also been proposed and investigated. In the simulation section, after introducing, reviewing, and compareing the common types of simulators, the... 

    Budget-constrained drone allocation for distribution system damage assessment

    , Article IET Smart Grid ; 2021 ; 25152947 (ISSN) Arjomandi Nezhad, A ; Moeini Aghtaie, M ; Fotuhi Firuzabad, M ; Aminifar, F ; Sharif University of Technology
    John Wiley and Sons Inc  2021
    Abstract
    Natural disasters threaten the sustainability of electric power supply. This fact highlights the importance of enhancing technological resourcefulness to handle the upcoming events. Once a natural disaster occurs, the most urgent undertaking is to rapidly pinpoint and assess component damages and dispatch the repair crews towards the most critical impaired elements. Practical efforts confirm that utilising a drone, which is an unmanned aerial vehicle, can notably reduce the duration of post-disaster distribution system damage assessment (DA) and increase the resilience of power systems. This study presents an optimisation model to determine the optimal number and type of drones required for... 

    A fast vacuum ARC detection method based on the neural network data fusion algorithm for the high-voltage DC power supply of vacuum tubes.رر

    , Article IEEE Transactions on Plasma Science ; Volume 49, Issue 1 , 2021 , Pages 476-485 ; 00933813 (ISSN) Ayoubi, R ; Kaboli, S ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2021
    Abstract
    Vacuum arc is one of the most important failure factors of the vacuum tubes. The amount of delivered energy from the high-voltage dc power supply to the vacuum tube is an important issue during the vacuum arc in the tube. Vacuum arc acts as a short-circuit fault (SCF) at the power supply output. The majority of converters use a single current sensor to measure only the converter output current for detecting the SCF. However, the sensor may provide unreliable data because of the noise effect. Application of a low-pass filter reduces the noise effect. Regarding the delay of the low-pass filter, the interval of arc detection increases and more energy is delivered to the tube. In this article, a... 

    CHANCE: Capacitor charging management scheme in energy harvesting systems

    , Article IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems ; Volume 40, Issue 3 , June , 2021 , Pages 419-429 ; 02780070 (ISSN) Hosseinghorban, A ; Bahrami, M. R ; Ejlali, A ; Abam, M. A ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2021
    Abstract
    The energy efficiency of emerging nonvolatile processors equipped with FRAM-SRAM memory makes them a promising solution for energy harvesting systems. To enable correct functionality and forward progress with an unreliable power supply, the system must accumulate sufficient energy in the capacitor to execute tasks atomically, even in the worst case scenario. Due to the large gap between the average and worst case energy consumption of tasks, state-of-the-art approaches like eM-map require a large capacitor to execute tasks on the SRAM. However, the size, cost, and charging time of the capacitor are major concerns in the energy harvesting systems. In this article, we proposed CHANCE, a... 

    Investigation of transient effects on FPGA-based embedded systems

    , Article ICESS 2005 - 2nd International Conference on Embedded Software and Systems, Xian, 16 December 2005 through 18 December 2005 ; Volume 2005 , 2005 , Pages 231-236 ; 0769525121 (ISBN); 9780769525129 (ISBN) Bakhoda, A ; Miremadi, S. G ; Zarandi, H. R ; Sharif University of Technology
    2005
    Abstract
    In this paper, we present an experimental evaluation of transient effects on an embedded system which uses SRAM-based FPGAs. A total of 7500 transient faults were injected into the target FPGA using Power Supply Disturbances (PSD) and a simple 8-bit microprocessor was implemented on the FPGA as the testbench. The results show that nearly 64 percent of faults cause system failures and about 63 percent of the faults lead to corruption of the configuration data of the FPGA chip. © 2005 IEEE  

    Experimental evaluation of transient effects on SRAM-based FPGA chips

    , Article 17th 2005 International Conference on Microelectronics, ICM 2005, Islamabad, 13 December 2005 through 15 December 2005 ; Volume 2005 , 2005 , Pages 251-255 ; 0780392620 (ISBN); 9780780392625 (ISBN) Bakhoda, A ; Miremadi, S. G ; Zarandi, H. R ; Sharif University of Technology
    2005
    Abstract
    This paper presents an experimental evaluation of transient effects on SRAM-based FPGAs. A total of 9000 transient faults were injected into the target FPGA using Power Supply Disturbances (PSD). The results show that nearly 60 percent of faults cause system failures and about 58 percent of the faults lead to corruption of the configuration data of the FPGA chip. © 2005 IEEE  

    Experimental evaluation of Master/Checker architecture using power supply- and software-based fault injection

    , Article Proceedings - 10th IEEE International On-Line Testing Symposium, IOLTS 2004, Madeira Island, 12 July 2004 through 14 July 2004 ; 2004 , Pages 239-244 ; 0769521800 (ISBN); 9780769521800 (ISBN) Rajabzadeh, A ; Miremadi, S. G ; Mohandespour, M ; Sharif University of Technology
    2004
    Abstract
    This paper presents an experimental evaluation of the effectiveness of the Master/Checker (M/C) architecture in a 32-bit Pentium® processor system using both power-supply disturbance (PSD) fault injection and software-implemented fault injection (SWIFI) methods. A total of 6000 faults were injected in the Master processor to measure the error detection coverage of the Checker processor. The results of the experiments with PSD fault injection show that the error detection coverage of the M/C architecture is about 66.13%, which is not quite effective. This low coverage depends on the high rate of Master processor hangs because of voltage fluctuation. The coverage increased to about 99.73% when... 

    Reducing the Flow Rate of Short Circuit Fault Current at the Output of the High Voltage Power Supply

    , M.Sc. Thesis Sharif University of Technology Zibarzani, Ali (Author) ; Kaboli, Shahriar (Supervisor)
    Abstract
    In this research, we have presented a method to delay the propagation of fault current in high voltage power supplies. Common protection methods usually protect the load and do not protect the power supply itself well. In this research, our goal was to propose a method to prevent the short circuit fault current from reaching the power supply elements. At first, the available methods to limit the fault current and protect the high voltage power sources were studied and investigated. Then, using the transmission line theory, a ladder filter was designed as an alternative to the normal filter at the output of the power supply. In the next step, using software simulation, the performance of the... 

    Improving Renewable Energy Usage in Data Centers with Distributed UPS Using Batch Job Scheduling

    , M.Sc. Thesis Sharif University of Technology Haghshenas, Kawsar (Author) ; Goudarzi, Maziar (Supervisor)
    Abstract
    In recent years, the demands come to data centers have increased significantly, so huge amount of energy consumption, cost of this usage and environmental effects of data centers have become serious issues. Accordingly using solar energy to provide some portion of a data center’s energy usage can reduce environmental effects efficiently. Also smarter use of this energy could decrease overall cost of energy in data center. The demands that come to a data center are categorized to critical and non-critical workloads. Running of Non-critical workload (batch job) can be moved to another time according to its deadline. This work suggests a solution that schedules batch jobs considering solar... 

    Sensorless Estimation of Lifetime of High-Voltage Power Supplies

    , M.Sc. Thesis Sharif University of Technology Sheikhi Azizi, Abbas (Author) ; Kaboli, Shahriyar (Supervisor)
    Abstract
    High voltage power supplies have a wide range of applications, and due to their high cost, it is essential to monitor their condition to predict potential failures and prevent significant losses. The most common cause of power supply failure is the wear and tear of its components. However, these components can be replaced before they wear out completely to prevent the failure of the power supply and, consequently, avoid damaging the load. Estimating the lifetime of power supplies is crucial because it allows for scheduled maintenance and helps prevent significant problems in power supplies. By estimating the lifespan of a power supply, one can anticipate when it may fail, allowing for the... 

    Recent Progress of Triboelectric Nanogenerators for Biomedical Sensors: From Design to Application

    , Article Biosensors ; Volume 12, Issue 9 , 2022 ; 20796374 (ISSN) Rahimi Sardo, F ; Rayegani, A ; Matin Nazar, A ; Balaghiinaloo, M ; Saberian, M ; Mohsan, S. A. H ; Alsharif, M. H ; Cho, H. S ; Sharif University of Technology
    MDPI  2022
    Abstract
    Triboelectric nanogenerators (TENG) have gained prominence in recent years, and their structural design is crucial for improvement of energy harvesting performance and sensing. Wearable biosensors can receive information about human health without the need for external charging, with energy instead provided by collection and storage modules that can be integrated into the biosensors. However, the failure to design suitable components for sensing remains a significant challenge associated with biomedical sensors. Therefore, design of TENG structures based on the human body is a considerable challenge, as biomedical sensors, such as implantable and wearable self-powered sensors, have recently... 

    Research on the effect of transients of high-voltage power supplies on the lifetime of high-power vacuum tubes: A microscopic assessment

    , Article IEEE Transactions on Plasma Science ; Volume 50, Issue 11 , 2022 , Pages 4700-4708 ; 00933813 (ISSN) Kaboli, S ; Ziaoddini, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2022
    Abstract
    Electron guns are used as the electron sources in high-power electron tubes. The generated electron beam in electric guns passes through an aperture at the center of the anode. Since the electron beam has considerable kinetic energy, any collision between the electron beam and the anode aperture edge damages the electron gun. Therefore, electron guns are designed to meet the compatibility between the diameters of the electron beam and the anode aperture. However, this compatibility is disrupted during the transient time interval of the gun's power supply. In this article, the cause of failure of the electron gun of high-power electron tubes is investigated for the transient interval of the... 

    Sustainable solutions for advanced energy management system of campus microgrids: model opportunities and future challenges

    , Article Sensors ; Volume 22, Issue 6 , 2022 ; 14248220 (ISSN) Muqeet, H. A ; Javed, H ; Akhter, M. N ; Shahzad, M ; Munir, H. M ; Nadeem, M. U ; Bukhari, S. S. H ; Huba, M ; Sharif University of Technology
    MDPI  2022
    Abstract
    Distributed generation connected with AC, DC, or hybrid loads and energy storage systems is known as a microgrid. Campus microgrids are an important load type. A university campus microgrids, usually, contains distributed generation resources, energy storage, and electric vehicles. The main aim of the microgrid is to provide sustainable, economical energy, and a reliable system. The advanced energy management system (AEMS) provides a smooth energy flow to the microgrid. Over the last few years, many studies were carried out to review various aspects such as energy sustainability, demand response strategies, control systems, energy management systems with different types of optimization... 

    Infrastructure aware heterogeneous-workloads scheduling for data center energy cost minimization

    , Article IEEE Transactions on Cloud Computing ; Volume 10, Issue 2 , 2022 , Pages 972-983 ; 21687161 (ISSN) Haghshenas, K ; Taheri, S ; Goudarzi, M ; Mohammadi, S ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2022
    Abstract
    A huge amount of energy consumption, the cost of this usage and environmental effects have become serious issues for commercial cloud providers. Solar energy is a promising clean energy source, to provide some portion of the Internet data center's (IDC's) energy usage which can reduce environmental effects and total energy costs. Moreover, due to the high energy consumption of the cooling system, considering cooling power in job scheduling can provide efficient solutions to reduce total energy consumption. In this article, we investigate the problem of minimizing the energy cost of an IDC and propose an algorithm which schedules heterogeneous IDC workloads, by considering available renewable... 

    Budget-constrained drone allocation for distribution system damage assessment

    , Article IET Smart Grid ; Volume 5, Issue 1 , 2022 , Pages 42-50 ; 25152947 (ISSN) Arjomandi Nezhad, A ; Moeini Aghtaie, M ; Fotuhi Firuzabad, M ; Aminifar, F ; Sharif University of Technology
    John Wiley and Sons Inc  2022
    Abstract
    Natural disasters threaten the sustainability of electric power supply. This fact highlights the importance of enhancing technological resourcefulness to handle the upcoming events. Once a natural disaster occurs, the most urgent undertaking is to rapidly pinpoint and assess component damages and dispatch the repair crews towards the most critical impaired elements. Practical efforts confirm that utilising a drone, which is an unmanned aerial vehicle, can notably reduce the duration of post-disaster distribution system damage assessment (DA) and increase the resilience of power systems. This study presents an optimisation model to determine the optimal number and type of drones required for... 

    A computational modelling study of excitation of neuronal cells with triboelectric nanogenerators

    , Article Scientific Reports ; Volume 12, Issue 1 , 2022 ; 20452322 (ISSN) Nazari Vanani, R ; Mohammadpour, R ; Asadian, E ; Rafii-Tabar, H ; Sasanpour, P ; Sharif University of Technology
    Nature Research  2022
    Abstract
    Neurological disorders and nerve injuries, such as spinal cord injury, stroke, and multiple sclerosis can result in the loss of muscle function. Electrical stimulation of the neuronal cells is the currently available clinical treatment in this regard. As an effective energy harvester, the triboelectric nanogenerators (TENG) can be used for self-powered neural/muscle stimulations because the output of the TENG provides stimulation pulses for nerves. In the present study, using a computational modelling approach, the effect of surface micropatterns on the electric field distribution, induced voltage and capacitance of the TENG structures have been investigated. By incorporating the effect of... 

    Operational strategy optimization of a hybrid green power system based on fuzzy logic controller with considering for optimal sizing and analysis of different priorities for energy storage

    , Article Sustainable Energy, Grids and Networks ; Volume 32 , 2022 ; 23524677 (ISSN) Zahedi, R ; Moeini Aghtaie, M ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    Renewable energy (RE) as a new player in the generation sector of power systems imposes new challenges to the system operators. The intermittent nature of REs for systems where are autonomous calls for new operational and planning strategies to reach more efficient power management. An autonomous hybrid green power system (HGPS) should be able to meet the load while keeping the cost of the HGPS as low as possible. Many studies have presented different un-optimal and optimal operational strategies, a few of which were optimally sized. In this regard, this paper develops a new thorough framework for designing and optimizing an autonomous HGPS. To reach this goal, the proposed model (a)... 

    Short-Circuit Failure Detection in Series-Connected IGBTs for Reliability Improvements

    , M.Sc. Thesis Sharif University of Technology Javidi, Pourya (Author) ; Kaboli, Shahriyar (Supervisor)
    Abstract
    In high-voltage power electronics systems where the supply voltage exceeds the maximum voltage these devices can withstand, series-connected IGBTs with TO-247 packaging and simultaneous gate command circuitry are used to create a high-voltage switch with an on and off time equivalent to a single IGBT. By considering voltage protection circuits for the series IGBTs, the large supply voltage is approximately evenly divided among the series switches. The resulting high-voltage switch has smaller conduction and switching losses compared to single high-voltage switches, has a lower finished price, and its turn-on time is much shorter due to their smaller gate-emitter junction capacitance...