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Integration of image de-blurring in an aerial Mono-SLAM
, Article Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering ; Vol. 228, issue. 8 , May , 2014 , p. 1348-1362 ; Gholampour, P ; Malaek, S. M. B ; Sharif University of Technology
2014
Abstract
In this article, we discuss the possibility of integrating image de-blurring techniques in an aerial simultaneous localization and mapping by a single camera (monocular simultaneous localization and mapping (Mono-SLAM)). We use an integrated aerial virtual environment together with a six-degree-of-freedom aircraft flight simulator to show the effectiveness of the approach to generate three-dimensional flight trajectories via integration of image de-blurring in the associated loop of the Mono-SLAM. The objective is to increase the overall performance of a flying mission over an unknown area by means of a vision-only method. The integrated aerial virtual environment produces and collects...
Prediction of aerial-image motion blurs due to the flying vehicle dynamics and camera characteristics in a virtual environment
, Article Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering ; Volume 227, Issue 7 , 2013 , Pages 1055-1067 ; 09544100 (ISSN) ; Malaek, S. M. B ; Sharif University of Technology
2013
Abstract
This study presents comprehensive studies on practical means to predict aerial-image motion blurs due to the flying vehicle dynamics, including flying altitude; cruising speed; and angular velocities and finally installed camera characteristics; such as, frame rate and image size. The resulting predictions of blur values are in-turn used to generate blurry images to be fed as input data for later use in a de-blurring-in-the-loop of a Mono-simultaneous localization and mapping system. The whole process is coordinated by means of an integrated aerial virtual environment. The integrated aerial virtual environment consists of a three-dimensional graphical engine which could communicate with a...
PBN-Based time-optimal terminal air traffic control using cellular automata
, Article IEEE Transactions on Aerospace and Electronic Systems ; Volume 57, Issue 3 , 2021 , Pages 1513-1523 ; 00189251 (ISSN) ; Amiri Atashgah, M. A ; Malaek, S. M. B ; Thulasiraman, P ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
Over the last decade, there has been an increase in air transportation, which has raised awareness to provide necessary procedures to respond to air transportation demands and reduce delay costs. One such procedure, 'performance-based navigation (PBN),' currently studied, is expected to increase the airspace capacity based on aircraft's individual performances. This research describes an efficient and expandable model for allocating standard terminal arrival route during continuous descent approach (CDA) that effectively uses PBN requirements. As a case study, we have considered the 'Atlanta International Airport' and verified the model's accuracy using real-time traffic data. The model is...
An integrated virtual environment for feasibility studies and implementation of aerial MonoSLAM
, Article Virtual Reality ; Volume 16, Issue 3 , September , 2012 , Pages 215-232 ; 13594338 (ISSN) ; Malaek, S. M. B ; Sharif University of Technology
2012
Abstract
This work presents a complete framework of an integrated aerial virtual environment (IAVE), which could effectively help implementing MonoSLAM (single-camera simultaneous localization and mapping) on an aerial vehicle. The developed system allows investigating different flight conditions without using any preloaded maps or predefined features. A 3D graphical engine integrated with a full 6 DOF aircraft dynamic simulator together with its trajectory generator completes the package. The 3D engine generates and accumulates real-time images of a general camera installed on the aerial vehicle. We effectively exploit C++ to develop the 3D graphics engine (3DGE) and all its associated visual...
A simulation environment for path and image generation in an aerial single-camera vision system
, Article Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering ; Volume 225, Issue 5 , 2011 , Pages 541-558 ; 09544100 (ISSN) ; Malaek, S. M. B ; Sharif University of Technology
2011
Abstract
This work describes the essential tools and architecture of a simulation environment, which could help enhance general aviation training as well as safety issues, especially while dealing with flights over unfamiliar environments. It also describes how the authors could effectively generate any desired flight path and its associated surrounding images through implementing a virtual single camera with simultaneous localization and mapping (monocular simultaneous localization and mapping) techniques. The overall package enjoys an aerial three-dimensional (3D)/graphical engine integrated with a full six-degrees-of-freedom aircraft dynamics, which serves as its trajectory generator, together...
A secure and efficient chaotic maps based authenticated key-exchange protocol for smart grid
, Article Wireless Personal Communications ; Volume 97, Issue 2 , 2017 , Pages 2551-2579 ; 09296212 (ISSN) ; Beheshti Atashgah, M ; Aref, M. R ; Sharif University of Technology
2017
Abstract
Nicanfar and Leung proposed a multilayer consensus elliptic curve based password authenticated key-exchange (MCEPAK) protocol for smart grid. They claimed that their protocol is secure against possible attacks. In this paper, we show that the MCEPAK protocol is vulnerable to the dictionary attack and an adversary can obtain the passwords of the appliances by eavesdropping the communicated messages in the protocol. Moreover, we state that the passwords can be discovered by curious operators of the building area networks and the neighbor area networks. Theses weaknesses motivated us to introduce a chaotic maps based authenticated key exchange protocol for smart grid. To the best of our...
Improvement on Q. Xie threshold proxy signature scheme against collusion attack
, Article 2011 19th Iranian Conference on Electrical Engineering, ICEE 2011, 17 May 2011 through 19 May 2011 ; May , 2011 , Page(s): 1 - 5 ; ISSN : 21647054 ; 9789644634284 (ISBN) ; Bayat, M ; Gardeshi, M ; Aref, M. R ; Sharif University of Technology
2011
Abstract
In a (t, n) threshold proxy signature scheme, the original signer can delegate the signing power to n proxy signers such that any t or more out of n proxy signers can sign messages on behalf of the original signer, but t -1 or less of the proxy signers cannot generate a proxy signature. In this paper, we will improve the security of Xie's threshold proxy signature scheme against the new types of collusion attack was presented by Liu and Tan in 2007 We also present that our improved scheme is more efficient than Xie's scheme in terms of computational complexities
A novel lattice-based proxy signature scheme
, Article ICEE 2012 - 20th Iranian Conference on Electrical Engineering, 15 May 2012 through 17 May 2012 ; May , 2012 , Pages 1224-1227 ; 9781467311489 (ISBN) ; Ajori, M ; Gardeshi, M ; Aref, M. R ; Sharif University of Technology
2012
Abstract
In a proxy signature scheme, an original signer delegates his/her signing capability to a proxy signer and then the proxy signer can sign messages on behalf of the original signer. The security of many proxy signature schemes that have been proposed depends, either directly or indirectly, on either the difficulty of big integers factoring problem or the difficulty of finding discrete logarithm in a finite group. These types of schemes cannot resist quantum attacks. In this paper, we propose a new lattice-based proxy signature scheme which can resist quantum attacks. The proposed scheme is based on the GGH-signature scheme and also satisfies all the security requirements of proxy signature...
ID-based strong designated verifier signature scheme and its applications in internet of things
, Article 27th Iranian Conference on Electrical Engineering, ICEE 2019, 30 April 2019 through 2 May 2019 ; 2019 , Pages 1486-1491 ; 9781728115085 (ISBN) ; Aref, M. R ; Bayat, M ; Barari, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
Strong designated verifier signature scheme is a concept in which a user (signer) can issue a digital signature for a special receiver; i.e. signature is produced in such way that only intended verifier can check the validity of produced signature. Of course, this type of signature scheme should be such that no third party is able to validate the signature. In other words, the related designated verifier cannot assign the issued signature to another third party. This article proposes a new ID-based strong designated verifier signature scheme which has provable security in the ROM (Random Oracle Model) and BDH assumption. The proposed scheme satisfies the all security requirements of an...
An ultra-lightweight RFID mutual authentication protocol
, Article 16th International ISC (Iranian Society of Cryptology) Conference on Information Security and Cryptology, ISCISC 2019, 28 August 2019 through 29 August 2019 ; 2019 , Pages 27-32 ; 9781728143736 (ISBN) ; Beheshti Atashgah, M ; Eghlidos, T ; Aref, M. R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
In some applications of the Internet of Things (IoT), for privacy preserving and authentication of entities, it is necessary to use ultra-lightweight cryptographic algorithms. In this paper, we propose a new ultra-lightweight authentication protocol between RFID components, in which only simple operations are used. In this protocol, the server has access to the data gathered by the tag in the same authentication phase through the reader interface, instead of sharing a secret key. The proposed protocol is secure against several attacks, such as replay attacks, denial of service, offline guessing attacks, modification attacks, full disclosure attacks and impersonation attacks, in addition to...
A lightweight anonymous authentication protocol for IoT wireless sensor networks
, Article 16th International ISC (Iranian Society of Cryptology) Conference on Information Security and Cryptology, ISCISC 2019, 28 August 2019 through 29 August 2019 ; 2019 , Pages 39-44 ; 9781728143736 (ISBN) ; Beheshti Atashgah, M ; Eghlidos, T ; Aref, M. R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
Lightweight authentication protocols are crucial for privacy preserving in Internet of Things (IoT). Authentication protocols should be implementable for devices with constrained memory and computational power in this area, in addition to resistance against cryptographic threats. On the other hand, these protocols should not impose a heavy computational load on such devices. In this paper we proposed an authentication protocol that properly meets these features. Our protocol is suitable for wireless sensor networks (WSNs). In this protocol, authentication is fulfilled with low communication and computational loads between sensors and users through the gateway interface using a hash function...
Aerial Vision-Based Navigation and Monitoring in Special Conditions
, Ph.D. Dissertation Sharif University of Technology ; Malaek, Mohammad Bagher (Supervisor)
Abstract
This research is dedicated to specific issues in the field of Aerial Vision Based Navigation (VBN). It focuses mainly on vehicles with no pilot such as RPVs and small aircraft; having in mind their safety which must be close to commercial applications. Various methods have been studied and the simplest one; which is based on observation, identification and utilization of landmarks is selected for detailed implementation. In this work, we concentrate on using a single-camera while flying in an unknown environment (MonoSLAM). Other available sensors are accelerometer and GPS receiver to keep the cost down. Different studies show that using a low-cost single camera system is much more efficient...
Butanol Production from Bagasse Sugarcane Black Liquor by Native Strain and Clostridium Acetobutylicum Species
,
M.Sc. Thesis
Sharif University of Technology
;
Shayegan, Jalaleddin
(Supervisor)
;
Vossoughi, Manouchehr
(Supervisor)
;
Sedighi, Mahsa
(Co-Supervisor)
Abstract
Considering the limitations of fossil fuels in recent years, as well as increasing demand for biofuels, it is anticipated that future attention to biofuels will increase further. Among biofuels, due to some disadvantages of bioethanol and biodiesel fuel, there is a tendency to use biobutanol, which does not have the disadvantages of the mentioned fuels. The cost of chemical production of butanol also led researchers to use biotechnology production of butanol. According to studies, butanol production can be achieved by fermenting some sugars such as glucose, xylose, and ... by anaerobic microorganism, but the cost of using these sugars has resulted in the use of natural sources of these...
Theoretical study of high repetition rate short pulse generation with fiber optical parametric amplification [electronic resource]
, Article Journal of Lightwave Technology ; May 2012, Volume 30, Issue 9, PP. 1263-1268 ; Ariaei, A. M ; Jadidi, M. M ; Salehi, J. A ; Sharif Unversity of Technology
Abstract
In this paper, we study theoretically the generation of high repetition rate short pulses using fiber optical parametric amplification. We show that the pulse shape and duration depend on the signal location relatively to the pump frequency. We demonstrate that in order to get the shortest pulse width, the signal must be located at one of the extremities of the gain spectrum associated with the pump peak power. We derive the analytical expression of the pulse shape in this case and compare it to the exponential gain regime case. Using numerical simulations, we also analyze the impact of walk-off and pump phase modulation that is required to suppress Stimulated Brillouin Scattering and derive...
A novel omega shaped microwave absorber with wideband negative refractive index for C-band applications
, Article Optik ; Volume 242 , 2021 ; 00304026 (ISSN) ; Baqir, M. A ; Iftikhar, A ; Ali, M. M ; Rahim, A. A ; Niaz Akhtar, M ; Mughal, M. J ; Naqvi, S. A ; Sharif University of Technology
Elsevier GmbH
2021
Abstract
This paper reports a polarization controllable and angle-insensitive perfect metamaterial absorber (PMA). The proposed PMA consists of periodically arranged asymmetric omega-shaped resonators made of metallic copper. The absorptivity was analyzed considering the microwave C-band from 4 GHz to 8 GHz. The proposed PMA shows an absorption peak with almost 100% absorptivity at 6.2 GHz. Also, wideband negative index of refraction is observed. Further, the absorber is inspected for the different rotation angles of the top metasurface (omega-shaped ring) along the optical axis, and obliquity of incidence angle for both TE and TM polarized waves. Moreover, surface electric field and surface current...
Formal process algebraic modeling, verification, and analysis of an abstract Fuzzy Inference Cloud Service
, Article Journal of Supercomputing ; Vol. 67, issue. 2 , February , 2014 , pp. 345-383 ; Online ISSN: 1573-0484 ; Rahmani, A. M ; Movaghar, A ; Teshnehlab, M
2014
Abstract
In cloud computing, services play key roles. Services are well defined and autonomous components. Nowadays, the demand of using Fuzzy inference as a service is increasing in the domain of complex and critical systems. In such systems, along with the development of the software, the cost of detecting and fixing software defects increases. Therefore, using formal methods, which provide clear, concise, and mathematical interpretation of the system, is crucial for the design of these Fuzzy systems. To obtain this goal, we introduce the Fuzzy Inference Cloud Service (FICS) and propose a novel discipline for formal modeling of the FICS. The FICS provides the service of Fuzzy inference to the...
Impact of holmium on structural, dielectric and magnetic properties of Cu–Zn spinel ferrites synthesized via sol–gel route
, Article Journal of Materials Science: Materials in Electronics ; Volume 32, Issue 2 , 2021 , Pages 2205-2218 ; 09574522 (ISSN) ; Khan, M. A ; Hussain, A ; Akhtar, M. N ; Ahmad, M ; Javid, M. A ; Sharif University of Technology
Springer
2021
Abstract
The mixed nano-ferrites materials Cu0.6Zn0.4HoxFe2−xO4 (0.00 ≤ x ≤ 0.12) were prepared via the sol–gel auto combustion technique. The TGA curve established the annealing temperature (500 °C) for phase formation. The single exothermic peak on the DSC plot occurred at 341 °C temperature. XRD patterns of these nano ferrites verified single phase formation of the FCC cubic structure. The lattice constant a was increased from 8.4244 to 8.4419 Å and then its value decreased to 8.4319 Å. Crystallite size was found in the range of 7 to 16 nm. The surface morphology of the samples was observed from the scanning electron microscope (SEM) images. The grain size was found within the range of 90 nm to...
Impact of holmium on structural, dielectric and magnetic properties of Cu–Zn spinel ferrites synthesized via sol–gel route
, Article Journal of Materials Science: Materials in Electronics ; Volume 32, Issue 2 , 2021 , Pages 2205-2218 ; 09574522 (ISSN) ; Khan, M. A ; Hussain, A ; Akhtar, M. N ; Ahmad, M ; Javid, M. A ; Sharif University of Technology
Springer
2021
Abstract
The mixed nano-ferrites materials Cu0.6Zn0.4HoxFe2−xO4 (0.00 ≤ x ≤ 0.12) were prepared via the sol–gel auto combustion technique. The TGA curve established the annealing temperature (500 °C) for phase formation. The single exothermic peak on the DSC plot occurred at 341 °C temperature. XRD patterns of these nano ferrites verified single phase formation of the FCC cubic structure. The lattice constant a was increased from 8.4244 to 8.4419 Å and then its value decreased to 8.4319 Å. Crystallite size was found in the range of 7 to 16 nm. The surface morphology of the samples was observed from the scanning electron microscope (SEM) images. The grain size was found within the range of 90 nm to...
An experimental study on mechanical behavior of a calcite cemented gravelly sand
, Article Geotechnical Testing Journal ; Volume 41, Issue 3 , May , 2018 , Pages 494-507 ; 01496115 (ISSN) ; Haeri, S. M ; Shahrabi, M. M ; Khosravi, A ; Sajadi, A. A ; Sharif University of Technology
ASTM International
2018
Abstract
In the study presented herein, a simple method for laboratory calcite cementation of a reconstituted gravelly sand was presented. This method was used to prepare cemented gravelly sand specimens, which have similar natural characteristics to alluvial deposit of the city of Tehran. The formation and distribution of calcite bonds, as well as the effectiveness of the presented calcite cementation method in increasing interparticle cohesion, as observed in weakly to moderately cemented soil in Tehran, were evaluated by means of chemical analysis, X-ray diffraction technique, and unconfined compressive strength tests. The cementation technique was used to prepare triaxial specimens with calcite...
A new dynamic optimal m2m rf interface setting in relay selection algorithm (dorsa) for iot applications
, Article IEEE Access ; Volume 10 , 2022 , Pages 5327-5342 ; 21693536 (ISSN) ; Hemmatyar, A. M. A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
Machine-to-Machine (M2M) communication is an important type of communication in the Internet-of-Things (IoT). How to send data in these high-density communications using relay selection can help improve the performance of this type of communication in various applications. In addition, the possibility of simultaneous use of different Radio Frequency (RF) interfaces helps to use the spectrum more efficiently. In this work, we try to further use machine communication RF equipment and improve the average data rate of networks in some applications such as the IoT, which have their own bandwidth requirements. Therefore, we provide an optimization algorithm for relay selection as well as the...