Loading...
Search for:
electronic-device
0.011 seconds
Total 28 records
A new 3D, microfluidic-oriented, multi-functional, and highly stretchable soft wearable sensor
, Article Scientific Reports ; Volume 12, Issue 1 , 2022 ; 20452322 (ISSN) ; Esmaeili Dokht, P ; Olyanasab, A ; Orouji, N ; Alipour, Z ; Sayad, M. H ; Rajabi, K ; Mazzolai, B ; Fardmanesh, M ; Sharif University of Technology
Nature Research
2022
Abstract
Increasing demand for wearable devices has resulted in the development of soft sensors; however, an excellent soft sensor for measuring stretch, twist, and pressure simultaneously has not been proposed yet. This paper presents a novel, fully 3D, microfluidic-oriented, gel-based, and highly stretchable resistive soft sensor. The proposed sensor is multi-functional and could be used to measure stretch, twist, and pressure, which is the potential of using a fully 3D structure in the sensor. Unlike previous methods, in which almost all of them used EGaIn as the conductive material, in this case, we used a low-cost, safe (biocompatible), and ubiquitous conductive gel instead. To show the...
Design of a Tester for GOOSE Messages Performance Testing Defined in IEC 61850
, M.Sc. Thesis Sharif University of Technology ; Jahangir, Amir Hossein (Supervisor)
Abstract
Nowadays, electrical energy is a necessity and the use of intelligent power equipment is expanding. Of course, having a protocol for communicating between such equipment is not only useful but sometimes mandatory. In the past, each equipment manufacturer used its own method for communication, hence, the "IEC 61850" standard was proposed as a solution to solve the problem of communication between different equipment. In this research, we intend to design a tester to perform a performance test with for GOOSE messages. These messages are based on the IEC 61850 data set and have the ability to quickly and securely distribute input and output values at the system level, which are transmitted by a...
Reliability evaluation of power grids considering integrity attacks against substation protective IEDs
, Article IEEE Transactions on Industrial Informatics ; Volume 16, Issue 2 , 2020 , Pages 1035-1044 ; Fotuhi Firuzabad, M ; Farzin, H ; Sharif University of Technology
IEEE Computer Society
2020
Abstract
Secure operation of protective intelligent electronic devices (IEDs) has been recognized as a crucial issue for power grids. By gaining access to substation IEDs, intruders can severely disrupt the operation of protection systems. This paper develops an analytical reliability assessment framework for quantifying the impacts of the hypothesized integrity attacks against protection systems. Petri net models are used to simulate possible intrusion scenarios into substation networks. The cyber network model is constructed from firewall, intrusion prevention system (IPS), and password models, which are three types of defense mechanisms for protecting substation networks. In this paper, two main...
Current-Transformer saturation prevention using a controlled voltage-source compensator
, Article IEEE Transactions on Power Delivery ; Volume 32, Issue 2 , 2017 , Pages 1039-1048 ; 08858977 (ISSN) ; Vakilian, M ; Sanaye Pasand, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
Current-transformer (CT) saturation causes severe distortion in the measured current waveform which may lead to maloperation of the protective devices. This paper proposes a low-cost, power-electronic device to prevent the CT from saturation. The proposed compensator is inserted in series with the relay in the CT secondary circuit and acts as a controlled voltage source (CVS). The proposed CVS generates a time-varying voltage to cancel the voltage developed across the CT burden; therefore, the CT magnetic flux remains almost constant and undistorted during the power system transients. It will be shown that this device can precisely compensate fault current, inrush current, and other probable...
Fabrication of a 2.8 V high-performance aqueous flexible fiber-shaped asymmetric micro-supercapacitor based on MnO2/PEDOT:PSS-reduced graphene oxide nanocomposite grown on carbon fiber electrode
, Article Journal of Materials Chemistry A ; Volume 8, Issue 37 , 2020 , Pages 19588-19602 ; Shahrokhian, S ; Soavi, F ; Sharif University of Technology
Royal Society of Chemistry
2020
Abstract
Flexible and lightweight fiber-shaped micro-supercapacitors have attracted tremendous attention as next-generation portable electronic devices, due to their high flexibility, tiny volume, and wearability. Herein, we successfully fabricated a ternary binder-free nanocomposite of MnO2/PEDOT:PSS-rGO on a carbon fiber substrate for application in high performance fiber-shaped micro-supercapacitors. The synergistic effects of the different components in the fiber-shaped electrode help to deliver a high specific capacitance of 2.9 F cm-2 (194 F cm-3 and 550 mF cm-1) at a current density of 5 mA cm-2 and a long cycle life with 95% capacitance retention after 5000 cycles in 1 M Na2SO4 electrolyte. A...
A new scheme for the development of IMU-based activity recognition systems for telerehabilitation
, Article Medical Engineering and Physics ; Volume 108 , 2022 ; 13504533 (ISSN) ; Eslaminia, A. R ; Bakhshayesh, P. R ; Ejtehadi, M ; Alibiglou, L ; Behzadipour, S ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Wearable human activity recognition systems (HAR) using inertial measurement units (IMU) play a key role in the development of smart rehabilitation systems. Training of a HAR system with patient data is costly, time-consuming, and difficult for the patients. This study proposes a new scheme for the optimal design of HARs with minimal involvement of the patients. It uses healthy subject data for optimal design for a set of activities used in the rehabilitation of PD1 patients. It maintains its performance for individual PD subjects using a single session data collection and an adaptation procedure. In the optimal design, several classifiers (i.e. NM, k-NN, MLP with RBF as a hidden layer, and...
Iterative machine learning-aided framework bridges between fatigue and creep damages in solder interconnections
, Article IEEE Transactions on Components, Packaging and Manufacturing Technology ; Volume 12, Issue 2 , 2022 , Pages 349-358 ; 21563950 (ISSN) ; Fotuhi Firuzabad, M ; Samavatian, M ; Dehghanian, P ; Blaabjerg, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
Costly and time-consuming approaches for solder joint lifetime estimation in electronic systems along with the limited availability and incoherency of data challenge the reliability considerations to be among the primary design criteria of electronic devices. In this article, an iterative machine learning framework is designed to predict the useful lifetime of the solder joint using a set of self-healing data that reinforce the machine learning predictive model with thermal loading specifications, material properties, and geometry of the solder joint. The self-healing dataset is iteratively injected through a correlation-driven neural network (CDNN) to fulfill the data diversity. Outcomes...
Circuit Printing for Low-Cost Electronics by Organic Inks
, M.Sc. Thesis Sharif University of Technology ; Sarvari, Reza (Supervisor)
Abstract
Due to the high cost of the conventional silicon-based circuits, printed electronic introduced as an ultra-low-cost saving techniques which are widely used in RFID tags, displays, sensors and thin film transistors and so on. Unlike the silicon-based devices, Organic materials are used in printed electronic devices, owing to this these devices can be used on large and flexible substrates like glass and plastic. Also in the printing method, there is no demand for expensive and time-consuming processes such as lithography or sputtering. Only by an ink-jet printer or graved cylinders the different layers of a device can be deposited. Besides these advantages of printed electronics to...
Programming of memristor crossbars by using genetic algorithm
, Article Procedia Computer Science, 6 October 2010 through 10 October 2010 ; Volume 3 , October , 2011 , Pages 232-237 ; 18770509 (ISSN) ; Shouraki, S. B ; Sharif University of Technology
2011
Abstract
Recently announcement of a physical realization of a fundamental circuit element called memristor by researchers at Hewlett Packard (HP) attracted so much interests and opened a new field in configurable or programmable electronic systems because it has properties of the perfect switch. Combination of this newly found circuit element with nanowire crossbar interconnect technology, creates a powerful platform which is called memristor crossbar. It has been demonstrated that this structure can offer the potential of creating configurable electronic devices which can have applications in signal processing and artificial intelligence. In this paper, we will highlight the rule that Genetic...
Residual flux mitigation of protective current transformers used in an autoreclosing scheme
, Article IEEE Transactions on Power Delivery ; Volume 31, Issue 4 , 2016 , Pages 1636-1644 ; 08858977 (ISSN) ; Salehizadeh, M ; Vakilian, M ; Sanaye Pasand, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
To avoid saturation of a protective current transformer (CT) operating under an autoreclosing scheme, the CT size should be chosen much higher than a similar CT operating under a single-step fault clearing scheme. The main reason for this significant difference is that the residual flux (caused by the first stage of the fault) cannot be noticeably reduced during the deadtime interval of the reclosing process and, therefore, the occurrence of a subsequent fault can extremely saturate the CT. In this paper, a low-cost, low-power electronic device is developed and introduced to demagnetize the CT under the reclosing deadtime interval. It will be shown that by using this device, the required...
A new delay attack detection algorithm for PTP network in power substation
, Article International Journal of Electrical Power and Energy Systems ; Volume 133 , 2021 ; 01420615 (ISSN) ; Jahangir, A. H ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Time synchronization is one of the main issues for guaranteeing the correctness of actions depending on the time of measured data or detected events by electronic devices across industrial networks. According to the accuracy needed in different applications and networks, several synchronization protocols or algorithms have been proposed so far. The Precision Time Protocol, PTP, is one of the most accurate synchronization protocols introduced for automation applications. It has also been used in power grids and digital substations. However, due to the variety of cyber-attacks in electrical power systems in recent years, its security should be considered and evaluated as other substation...
ECG classification algorithm based on STDP and R-STDP neural networks for real-time monitoring on ultra low-power personal wearable devices
, Article IEEE Transactions on Biomedical Circuits and Systems ; Volume 13, Issue 6 , 2021 , Pages 1483-1493 ; 19324545 (ISSN) ; Hashemi, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
This paper presents a novel ECG classification algorithm for inclusion as part of real-time cardiac monitoring systems in ultra low-power wearable devices. The proposed solution is based on spiking neural networks which are the third generation of neural networks. In specific, we employ spike-timing dependent plasticity (STDP), and reward-modulated STDP (R-STDP), in which the model weights are trained according to the timings of spike signals, and reward or punishment signals. Experiments show that the proposed solution is suitable for real-time operation, achieves comparable accuracy with respect to previous methods, and more importantly, its energy consumption in real-time classification...
Reliability assessment of some high side MOSFET drivers for buck converter
, Article 2013 3rd International Conference on Electric Power and Energy Conversion Systems, EPECS 2013, Istanbul ; 2013 ; 9781479906888 (ISBN) ; Kaboli, S ; Sharif University of Technology
2013
Abstract
Nowadays power electronic devices have a wide usage in the industries and different electrical equipment for power conditioning. As a point of view, reliability is one of important figure of merits that should be considered to have long life time and also have more probability to do exactly the proposed mission. In this paper some methods are presented to improve the reliability of power electronic components. Also some methods of system reliability improvement are reviewed. One group of converters is DC-DC step down converter which is used in different applications such as battery charger and voltage regulator. In this paper as an example, reliability of a DC-DC step down converter with...
Quantitative modeling and analysis of substation automation systems
, Article Proceedings of the IEEE Power Engineering Society Transmission and Distribution Conference ; 2012 ; 21608555 (ISSN) ; 9781467319348 (ISBN) ; Darabi, Z ; Fu, Y ; Vakilian, M ; Sharif University of Technology
2012
Abstract
The application of digital technologies in power systems has resulted in an evolutionary replacement of electromechanical devices with numerical ones featuring internal digital processors with communication capabilities. A substation automation system (SAS) deploys substation operation functions, including control, protection, monitoring, and measuring. Ethernet technology and local area networks (LANs) make it possible to design substation communication architectures with greater reliability, availability, speed, and cost savings than conventional hard-wired systems. This paper proposes a new method to describe topologies of the SAS as an interconnected network. The concept of data...
Ceria reinforced nanocomposite solder foils fabricated by accumulative roll bonding process
, Article Journal of Materials Science: Materials in Electronics ; Volume 23, Issue 9 , September , 2012 , Pages 1698-1704 ; 09574522 (ISSN) ; Kokabi, A. H ; Miyashita, Y ; Mutoh, Y ; Rezayat, M ; Madaah Hosseini, H. R ; Sharif University of Technology
Springer
2012
Abstract
As one of the key technologies for high performance electronic devices, composite solders have been recently developed to improve thermal and mechanical properties of solder joints. In this study, accumulative roll bonding process was used as an effective alternative method for manufacturing high-strength, finely dispersed, void-free and highly uniform Sn-Ag-Cu/CeO 2 nanocomposite solders. Microstructural investigation of nanocomposite solders revealed that homogenous distribution of CeO 2 nanoparticle has been achieved and the eutectic as-cast morphology of the solder changed to recrystallized fine grained structure. As a result of severe plastic deformation during rolling, brittle and...
Materials selection for electronic enclosures in space environment considering electromagnetic interference effect
, Article Advances in Space Research ; Volume 49, Issue 3 , February , 2012 , Pages 586-593 ; 02731177 (ISSN) ; Abedian, A ; Sharif University of Technology
2012
Abstract
Using low power electronic devices for space applications to reduce the mass and energy consumption has lead to electromagnetic interference (EMI) problem. Electronic enclosures are used to shield electronic devices against EMI. In the past, electromagnetic shielding has been mainly the only criteria considered in electronic enclosure design. However, there are several structural and thermal requirements for selection of shielding materials which should also be taken into account. In this research work, three quantitative materials selection methods, i.e. Digital Logic (DL), Modified Digital Logic (MDL), and Z-transformation, are employed to select the best material from among a list of...
Coupled plasmonic quantum bits
, Article Proceedings of SPIE - The International Society for Optical Engineering, 24 January 2010 through 28 January 2010 ; Volume 7608 , January , 2010 ; 0277786X (ISSN) ; 9780819480040 (ISBN) ; Sodagar, M ; Khoshnegar, M ; Khorasani, S ; Adibi, A ; Sharif University of Technology
2010
Abstract
In this paper we introduce a coupled system of two quantum bits residing at the interface of a heterostructure device. The structure encompasses a reference quantum bit, a photonic/plasmonic crystal waveguide and an obedient quantum bit. Each quantum bit is an electronic device which is designed based on an anti-dot lattice of two-dimensional electron gas in heterostructures. By applying a potential gate in the aforementioned structure it is possible to control electronic tunneling rate and hence quantum bits' swapping frequency. Coupling through the plasmonic waveguide may be employed to entangle quantum bits. The waveguide has been designed by exploiting conducting islands of...
Guest editorial: special section on asset management in smart grid
, Article IEEE Transactions on Smart Grid ; Volume 6, Issue 2 , 2015 , Pages 953-954 ; 19493053 (ISSN) ; Khodaei, A ; Matevson, J ; Li, Z ; Bertling, L ; Passo, E. A ; Fotuhi Firuzabad, M ; Sharif University of Technology
Abstract
Electric power system and its components, most of which developed based on the rising electricity demand during economic growth periods of 1970s and 1980s, have aged and some are not being replaced quickly. In addition, the integration of variable sources of energy has changed the way assets are being managed for optimal operation. Aging assets and uncertainty in power system load profile and demand management create a challenge for the optimal operation and maintenance of the electricity grid. This special section aims at addressing the challenges and opportunities in deployment of smart grid technologies such as wireless sensors for condition monitoring and intelligent electronic devices...
A novel soft-switching seven-level converter topology with self-voltage balancing ability
, Article IEEE AFRICON Conference, 23 September 2009 through 25 September 2009 ; 2009 ; 9781424439195 (ISBN) ; Poure, P ; Saadate, S ; Abbaspour Tehrani Fard, A ; Sharif University of Technology
Abstract
One of the major limitations of the multilevel converters is the voltage unbalance between different levels. The techniques to balance the voltage between the different levels normally involve voltage clamping or capacitor charge and discharge control. However, traditional Flying Capacitor Converter (FCC) may be quite limited by the voltage unbalance of flying-capacitors that is the most serious problem. This paper describes operating principles of a new softswitching seven-level converter topology based on FCC for self-voltage stabilization and balancing. By adding power electronic devices to the traditional FCC topology, the proposed topology regulates the DC bus voltage and balances the...
High-Performance fiber-shaped flexible asymmetric microsupercapacitor based on ni(oh)2 nanoparticles-decorated porous dendritic ni-cu film/cu wire and reduced graphene oxide/carbon fiber electrodes
, Article ACS Sustainable Chemistry and Engineering ; Volume 6, Issue 11 , 2018 , Pages 14574-14588 ; 21680485 (ISSN) ; Naderi, L ; Mohammadi, R ; Sharif University of Technology
American Chemical Society
2018
Abstract
Miniaturization of electronic devices with portable, flexible and wearable characteristics created a great demand for high-performance microscale energy storage devices with lightweight and flexible properties. Among the energy storage devices, wire-shaped supercapacitors (WSSCs) have recently received tremendous attention due to their tiny volume, wearability, high flexibility and potential applications in the next-generation portable/wearable electronic devices. Herein, we successfully fabricated a porous dendritic Ni-Cu film on Cu wire substrate (CWE) for fabrication of high-performance wire-type supercapacitors. The porous structure with dendritic morphology provides a high surface area,...