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ELITE: An elaborated cross-layer rpl objective function to achieve energy efficiency in internet-of-things devices
, Article IEEE Internet of Things Journal ; Volume 8, Issue 2 , 2021 , Pages 1169-1182 ; 23274662 (ISSN) ; Hosseini Monazzah, A. M ; Ejlali, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
Energy consumption is a major challenge in IoT devices, which was aimed to be improved by employing energy-efficient objective functions (OFs) in the structure of the RPL routing protocol. Meanwhile, the majority of the existing OFs mainly perform the parent selection based on the gathered information from the routing layer. Nevertheless, based on our investigations, there exists a series of transmission operations in the medium access control (MAC) layer, which significantly affects the energy consumption in IoT devices. Therefore, in this article, we propose ELITE, an energy-efficient cross-layer OF, which introduces a novel routing metric, called strobe per packet ratio (SPR). SPR...
Effects of RPL objective functions on the primitive characteristics of mobile and static IoT infrastructures
, Article Microprocessors and Microsystems ; Volume 69 , 2019 , Pages 79-91 ; 01419331 (ISSN) ; Mohammad Salehi, A. A ; Hosseini Monazzah, A. M ; Ejlali, A ; Sharif University of Technology
Elsevier B.V
2019
Abstract
The emergence of mobile IoT applications in recent years and the challenge of routing in their infrastructures have motivated scholars to propose appropriate routing mechanisms for such systems. Meanwhile, the IPv6 Routing Protocol for Low Power and Lossy Networks (RPL) is the standard routing protocol for IoT infrastructures. Nevertheless, RPL was mainly designed to comply with the primitive requirements of static IoT applications and it behaves poorly in confronting with the severe alterations in mobile conditions. The most important factor for such a poor behavior in mobile applications is the inappropriate design of OFs, which determine RPL's routing policies in the network. Therefore,...
Multiobjective design of an S control chart for monitoring process variability
, Article International Journal of Multicriteria Decision Making ; Volume 2, Issue 4 , 2012 , Pages 408-424 ; 2040106X (ISSN) ; Kazemzadeh, R. B ; Niaki, S. T. A ; Sharif University of Technology
2012
Abstract
Optimally determining parameters of the control chart is a critical task for control chart designer to improve the processes. However, difficulty in an accurate estimation of various cost and process parameters is one of the barriers while someone desire to determine these parameters by means of economic approach. In order to reduce cost penalties for not knowing the true values of the parameters and to study the impact of further improvement in detection power of the chart on the economic performance of the S control chart, this paper aims to develop a multiobjective model of the economic-statistical design of the S control chart to minimise the mean hourly loss cost as well as minimising...
Spatial resolution enhancement in fiber Raman distributed temperature sensor by employing ForWaRD deconvolution algorithm
, Article Optical Fiber Technology ; Volume 17, Issue 2 , 2011 , Pages 128-134 ; 10685200 (ISSN) ; Moosavi, A ; Bahrampour, M. J ; Safaei, L ; Sharif University of Technology
2011
Abstract
Governing equations of a Raman fiber distributed temperature sensor supported by a counter propagating pumped Raman amplifier are written in the form of integral equations. Forward pump and backward going probe are in the pulsed and continuous wave modes of operation respectively. It is shown that powers of the forward and backward Raman signals (stokes and anti stokes) approximately are the convolution of the input forward pump pulse and corresponding optical fiber impulse responses. The Fourier Wavelet Regularized Deconvolution (ForWaRD) method is employed to improve the spatial resolution in fiber Raman distributed temperature sensor without reducing the pulse width of the laser source
Multi-Objective economic statistical design of X-Bar control chart considering taguchi loss function
, Article International Journal of Advanced Manufacturing Technology ; Volume 59, Issue 9-12 , April , 2012 , Pages 1091-1101 ; 02683768 (ISSN) ; Kazemzadeh, R. B ; Niaki, S. T. A ; Sharif University of Technology
2012
Abstract
Shewhart charts are the most popular control charts that can be used to monitor variable quality characteristics in a production process. In this paper, a multi-objective model of the economic statistical design of the X-bar control chart is first proposed by incorporating the Taguchi loss function and the intangible external costs. The model minimizes the mean hourly loss cost while minimizing out-of-control average run length and maintaining reasonable in-control average run length. A multiobjective evolutionary algorithm, namely NSGA-II, is then developed and used to obtain the Pareto optimal solution of the model. Some sensitivity analyses are next performed to investigate the effect of...
Dynamic routing of data stream tuples among parallel query plan running on multi-core processors
, Article Distributed and Parallel Databases ; Volume 30, Issue 2 , April , 2012 , Pages 145-176 ; 09268782 (ISSN) ; Sharifrazavian, A ; Sharifi, M ; Haghjoo, M. S ; Sharif University of Technology
2012
Abstract
In this paper, a method for fast processing of data stream tuples in parallel execution of continuous queries over a multiprocessing environment is proposed. A copy of the query plan is assigned to each of processing units in the multiprocessing environment. Dynamic and continuous routing of input data stream tuples among the graph constructed by these copies (called the QueryMega Graph) for each input tuple determines that, after getting processed by each processing unit (e.g., processor), to which next processor it should be forwarded. Selection of the proper next processor is performed such that the destination processor imposes the minimum tuple latency to the corresponding tuple, among...
Objective function: a key contributor in internet of things primitive properties
, Article CSI International Symposium on Real-Time and Embedded Systems and Technologies, RTEST 2018 ; 26 June , 2018 , Pages 39-46 ; 9781538614754 (ISBN) ; Hosseini Monazzah, A. M ; Shahroodi, T ; Ejlali, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
With the widespread use of Internet of Things (IoT) in every aspect of human's daily life, communications of such an enormous amount of existing embedded devices in these systems arise many new challenges from power consumption, performance, and reliability perspectives. Communications in an IoT infrastructure are managed by a set of policies which are determined by Objective Functions (OFs). Thus, OFs are the most important contributors in facing with the mentioned challenges. In this paper, due to the lack of information on how OFs affect the primary properties of an IoT infrastructure, we have compared three well-known OFs (OF0, MRHOF, and OFFL) from power consumption, performance, and...
Learning-Oriented QoS- and drop-aware task scheduling for mixed-criticality systems
, Article Computers ; Volume 11, Issue 7 , 2022 ; 2073431X (ISSN) ; Alikhani, H ; Safaei, B ; Ejlali, A ; Kumar, A ; Sharif University of Technology
MDPI
2022
Abstract
In Mixed-Criticality (MC) systems, multiple functions with different levels of criticality are integrated into a common platform in order to meet the intended space, cost, and timing requirements in all criticality levels. To guarantee the correct, and on-time execution of higher criticality tasks in emergency modes, various design-time scheduling policies have been recently presented. These techniques are mostly pessimistic, as the occurrence of worst-case scenario at run-time is a rare event. Nevertheless, they lead to an under-utilized system due to frequent drops of Low-Criticality (LC) tasks, and creation of unused slack times due to the quick execution of high-criticality tasks....
Weighing criteria and prioritizing strategies to reduce motorcycle-related injuries using combination of fuzzy topsis and ahp methods
, Article Advances in Transportation Studies ; Volume 54 , 2021 , Pages 217-234 ; 18245463 (ISSN) ; Safaei, N ; Masoud, A ; Seyedekrami, S ; Sharif University of Technology
Aracne Editrice
2021
Abstract
Unsafe driving behavior and hazardous environmental conditions lead lo traffic crashes and injuries. The annual rale of road crashes in Iran is twenty times higher than the world's average. Motorcycle crashes have higher fatality rates than other motor vehicle crashes, and they exert psychological pressure on the communities and have adverse economic consequences for the societies. This paper analyzes Tehran's motorcycle crash data and investigates the effective underlying factors. Seven strategies were presented and prioritized to reduce the number and severity of motorcycle crashes. The fuzzy Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) combined with the...
A novel LNA circuit in the L band with the purpose of increasing gain in GSM GPS in wireless multi-receiver systems
, Article 2nd International Conference on Communication Engineering and Technology, ICCET 2019, 12 April 2019 through 15 April 2019 ; 2019 , Pages 163-167 ; 9781728114392 (ISBN) ; Arvandi, A ; Ashtarayeh, M ; Safaei, B ; Hosseini Monazzah, A. M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
In this paper, a noise amplifier circuit in the L-band frequency (lGHz-2GHz) has been designed and implemented through the Advanced Design System (ADS) software. In this circuit, the Cascade technique is utilized in order to amplify the signal. In addition, current reuse, in-ductive feedback, and the inductive square pair techniques are exploited to increase the gain in linearity mode, isolate the signal, and match the input and output networks. There are three objectives for designing this circuit, i.e., increasing the gain, improving the signal stability in the Frequency linearity Bandwidth (L), and enhancement in the NF value. The proposed circuit includes four levels of transistors with...
COACH: Consistency aware check-pointing for nonvolatile processor in energy harvesting systems
, Article IEEE Transactions on Emerging Topics in Computing ; Volume 9, Issue 4 , December , 2021 , Pages 2076-2088 ; 21686750 (ISSN) ; Hosseini Monazzah, A. M ; Bazzaz, M ; Safaei, B ; Ejlali, A ; Sharif University of Technology
IEEE Computer Society
2021
Abstract
Recently, energy harvesting systems that utilize hybrid NVM-SRAM memory in their designs are introduced as a promising alternative for battery-operated systems. Since the ambient input power of an energy harvesting system fluctuates as the environmental conditions change, the system may stop the execution of programs until it receives enough energy to continue the execution. Resuming the execution of a program after the suspension may lead to data inconsistency in an energy harvesting system and threatens the correct functionality of the programs. In this article, we propose COACH, an energy-efficient consistency-aware memory scheme which guarantees the correct functionality and consistency...
A robust PN length estimation in down link low- SNR DS-CDMA multipath channels
, Article International Conference on Advanced Communication Technology, ICACT, 7 February 2010 through 10 February 2010 ; Volume 2 , February , 2010 , Pages 951-955 ; 17389445 (ISSN) ; 9788955191455 (ISBN) ; Ganji, F ; Safaei, A ; Samsami Khodadad, F ; Sharif University of Technology
2010
Abstract
In this paper an efficient method is proposed for blind detection of multiuser spread spectrum signal and pseudo noise (PN) length estimation in downlink scenario. This method is based on fluctuating observation of second order statistic (SOS) estimator of received signal; estimating length of spreading code with no need to primary information based on observing second order peaks of correlation estimator is presented. In low SNR, the fading multipath phenomenon especially in length of small codes leads to problem in detecting place of correlation estimator peaks. In this paper besides expanding blind estimation to multiuser environment, by using searching method in updating the length of...
Observer-free control of satellite attitude using a single vector measurement
, Article IEEE Transactions on Aerospace and Electronic Systems ; Vol. 50, issue. 3 , 2014 , pp. 2070-2081 ; ISSN: 00189251 ; Namvar, M ; Sharif University of Technology
2014
Abstract
The existing methods in attitude control of satellites are based on using the estimate of satellite attitude, which is usually generated by using multiple vector measurements. In this paper we propose an output feedback controller that directly uses a single vector measurement and does not use an attitude estimator. The output feedback gain is computed by solving a generalized Riccati differential equation (GRDE). The existence of a solution to the GRDE depends on a uniform controllability condition
Output feedback control of satellite attitude using a single vector measurement
, Article Proceedings of the IEEE Conference on Decision and Control, 10 December 2012 through 13 December 2012, Maui, HI ; 2012 , Pages 490-495 ; 01912216 (ISSN) ; Namvar, M ; Sharif University of Technology
2012
Abstract
The existing methods in attitude control of satellites are based on employing the estimate of satellite attitude which is usually generated by using multiple vector measurements. In this paper we propose an output feedback control law that directly uses a single vector measurement and gyro, and without any need for estimating the satellite attitude. The output feedback gain is computed by solving a generalized Riccati time varying differential equation. We assume the moment-of-inertia matrix of satellite is unknown. The controller guarantees asymptotic convergence of the attitude to its desired value. A realistic simulation is presented where a magnetometer is used to provide the single...
3D motion recognition using HMM and nearest neighbor method
, Article Proceedings of the IASTED International Conference on Signal Processing, Pattern Recognition and Applications, SPPRA 2012 ; 2012 , Pages 17-22 ; 9780889869219 (ISBN) ; Jahed, M ; Sharif University of Technology
ACTA Press
2012
Abstract
Gesture and motion recognition are needed for a variety of applications. The use of human hand motions as a natural interface tool has motivated researchers to conduct research in the modeling, analysis and recognition of various hand movements. In this work, we introduce a 3-D hand motion recognition. We use 3-D landmarked points on finger tips and joints followed by a HMM (Hidden Markov Model) to recognize hand motions. Experimentally, in an effort to evaluate the formation of hand gestures similar to those used in rehabilitation sessions, we studied three hand motions. Using natural hand motion features in an uncontrolled environment, we were able to classify, differentiate and quantify...
On the design of graphene oxide nanosheets membranes for water desalination
, Article Desalination ; Volume 422 , 2017 , Pages 83-90 ; 00119164 (ISSN) ; Tavakoli, R ; Sharif University of Technology
Elsevier B.V
2017
Abstract
According to current researches, graphene oxide (GO) membranes show promising desalination properties due to ease of synthesis, low production cost, and high efficiency. There are several experimental works to study ionic sieving properties of GO membranes. However, it is difficult to characterize atomistic mechanism of water permeation and ion rejection by experimental approaches. On the other hand, there exist a few reports in which the atomistic picture of water permeation across GO membranes is investigated by means of molecular dynamics (MD) simulation. In the present work, in addition to water desalination, the atomic scale mechanism of ion rejection is studied using large scale MD...
Quine-McCluskey classification
, Article 2007 IEEE/ACS International Conference on Computer Systems and Applications, AICCSA 2007, Amman, 13 May 2007 through 16 May 2007 ; 2007 , Pages 404-411 ; 1424410312 (ISBN); 9781424410316 (ISBN) ; Beigy, H ; Sharif University of Technology
2007
Abstract
In this paper the Karnaugh and Quine-McCluskey methods are used for symbolic classification problem, and then these methods are compared with other famous available methods. Because the data in classification problem is very large, some changes should be applied in the original Quine-McCluskey (QMC) algorithm. We proposed a new algorithm that applies the QMC algorithm greedily calling it GQMC. It is surprising that GQMC results are most of the time equal to QMC. GQMC is still very slow classifier and it can be used when the number of attributes of the data is small, and the ratio of training data to the all possible data is high. © 2007 IEEE
Entanglement Spectrum of One Dimensional Ising Model in Transverse Field
, M.Sc. Thesis Sharif University of Technology ; Langari, Abdollah (Supervisor)
Abstract
Entanglement spectrum is the set of eigenvalues of reduced density matrix for a definite state. It contains more information than the entanglement entropy. This spectrum can show entanglement measure, quantum phase transition and topological order in a system. In recent years, the entanglement spectrum for several models has been studied. The entanglement spectrum shows a correspondence to the energy spectrum within some specific regions, which are related to the edge state of the system; It has been verified for the Heisenberg ladder [1] and fractional quantum Hall effect [3]. Moreover, the topological order can be seen in the entanglement spectrum. There exists an acceptable adaption...
Automatic Hand and Wrist Motion Tracking and Assessment Using Stereo Vision and Video Processing
, M.Sc. Thesis Sharif University of Technology ; Jahed, Mehran (Supervisor)
Abstract
Gesture and motion evaluation are needed for a variety of applications. The use of human hand motions as a natural interface tool has motivated researchers to conduct research in the modeling, analysis and evaluation of various hand movements. In particular, human-computer intelligent interaction has been a focus of research in vision-based gesture recognition. In this work, we introduce a 3-D hand model evaluation method that offers flexible and elaborate representation of hand motion. We used landmarked points on tips and joints of the fingers and calculated the 3-D coordinates of these points through a stereo vision system followed by an HMM (Hidden Markov Model) to recognize hand...
Fault Tolerance in Cloud Storage Systems Using Erasure Codes
, M.Sc. Thesis Sharif University of Technology ; Miremadi, Ghassem (Supervisor)
Abstract
International Data Company (IDC) has reported, at the end of 2020, the total amount of digital data stored in the entire world will reach 40 thousand Exabytes. The idea of accessing this volume of data, anywhere at any time by exploiting commodity hardware, led into the introduction of cloud storage. The abounded rate and variety of failures in the equipment used in cloud storage systems, placed fault tolerance, at top of the challenges in these systems. HDFS layer in Hadoop has provided cloud with reliable storage. Replication is the conventional method to protect data against failures in HDFS. But the storage overhead is a big deal and therefore designers are tending towards erasure codes....