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Biclique cryptanalysis of Twine-128
, Article 13th International ISC Conference on Information Security and Cryptology, 7 September 2016 through 8 September 2016 ; 2016 , Pages 46-51 ; 9781509039494 (ISBN) ; Zare Ahangarkolaei, M ; Ahmadi, S ; Aref, M. R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
Security evaluation of lightweight block ciphers plays a critical role to determine security margin of these ciphers. One of the methods to find the security margin of block ciphers is biclique cryptanalysis. In this paper, we present a new schematic for biclique attack which combines asymmetric biclique and early abort technique. Then, we apply it against Twine-128 to evaluate the security margin of Twine-128. As a result, we present two cryptanalysis for Twine-128, one with 2125.75 computational complexity and 260 data complexity, and the other with 212616 computational complexity and 28 data complexity. To the best of our knowledge, our results are the best in computational and data...
Zero correlation linear attack on reduced round Piccolo-80
, Article 13th International ISC Conference on Information Security and Cryptology, 7 September 2016 through 8 September 2016 ; 2016 , Pages 66-71 ; 9781509039494 (ISBN) ; Hoseini Najarkolaei, S. R ; Ahmadi, S ; Aref, M. R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
Universal deployment of lightweight block ciphers increase the importance of cryptanalysis of these ciphers. In this paper, we focus on reduced round version of Piccolo-80 as a lightweight block cipher and try to analyze it by zero correlation linear attack. As a result, we proposed a new zero correlation linear attack on 12-round Piccolo-80 without whitening keys with computational complexity of 251.4, while memory and data complexities of the attack are equal to 258.2 and 250, respectively. Also, we proposed an attack on 12-round Piccolo-80 with whitening keys and 13-round Piccolo-80 without whitening keys. To the best of our knowledge, these are the first zero correlation attacks on...
Experimental Investigation of Three Dimensional Turbidity Current
, M.Sc. Thesis Sharif University of Technology ; Firoozabadi, Bahar (Supervisor)
Abstract
Dense underflows are continuous currents which move down slope due to the fact that their density is heavier than ambient water. Driven by density differences between the inflow and clear water in the reservoirs, the density current plunges the clear water and moves on the bed. While density currents flowing on a sloping bed, the vertical spreading due to water entrainment plays an important role in determining the propagation rate in the longitudinal direction. These currents are similar to wall-jet currents according to structure of the flows but are complicated relative to wall-jet currents due to the existence of density difference. Characteristics of the density current sometimes are...
Implementing distance line protection schemes among IEC61850-enabled substations
, Article Proceedings of the IEEE Power Engineering Society Transmission and Distribution Conference ; April , 2014 , Page(s): 1 - 5 ; ISSN: 21608555 ; ISBN: 9781479936557 ; Darabi, Z ; Vakilian, M
2014
Abstract
As digital technology has developed, relays have evolved from simple electro-mechanical devices into robust microprocessor-embedded intelligent electronic devices (IEDs). Distance protection, one of the most important and sophisticated forms of substation protection, quickly and selectively detects and clears phase faults in sub-transmission and transmission lines. The installation of a substation automation system (SAS) involves implementing control, monitoring, and protection logic by programming the IEDs and providing an appropriate communication network. IEC61850 has gradually satisfied the need for a standard communication protocol so that IEDs from different manufacturers can...
Fault Tolerant Distributed Computing in Deep Neural Networks
, M.Sc. Thesis Sharif University of Technology ; Aref , Mohammad Reza (Supervisor) ; Maddah Ali, Mohammad Ali (Co-Supervisor)
Abstract
Nowadays, with the development of machine learning and deep learning on one hand, and the dramatic increase in the amount of information available and the complexity of models on the other hand, it is practically impossible to implement learning algorithms on a single node. Thus it is inevitable to distribute learning algorithms on several machines. In a distributed system, the main operations are divided into smaller tasks and performed by different nodes. The final result is then calculated by exchanging messages among the existing nodes.In this thesis, a method is introduced to compute the gradient of a massive data set in a distributed system. In this problem, there are a number of...
Improvement of the microfluidic microbial fuel cell using a nickel nanostructured electrode and microchannel modifications
, Article Journal of Power Sources ; Volume 437 , 2019 ; 03787753 (ISSN) ; Ghasemi, S ; Sanaee, Z ; Ghobadi Nejad, Z ; Mardanpour, M. M ; Yaghmaei, S ; Ghorbanzadeh, M ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this study, the effect of utilization of a nanostructured nickel based material as a negative electrode on the performance of microfluidic microbial fuel cell (MFC) with Escherichia coli as biocatalyst has been investigated. Designing the microfluidic MFC with nickel nanostructure resulted in a higher volumetric power density of 343 W m−3 compared to the previously published results. The assessment of effective parameters on the electrochemical performance of cell was investigated. The investigation of the hydraulic diameter impact on the power generation proves that reducing the microchannel hydraulic diameter from 1000 to 350 μm minimized the internal mass-transfer resistance, and...
Interactions of coinage metal clusters with histidine and their effects on histidine acidity; Theoretical investigation
, Article Organic and Biomolecular Chemistry ; Volume 10, Issue 47 , Oct , 2012 , Pages 9373-9382 ; 14770520 (ISSN) ; Jamshidi, Z ; Tehrani, Z. A ; Fattahi, A ; Sharif University of Technology
2012
Abstract
Understanding the nature of interaction between metal nanoparticles and biomolecules such as amino acids is important in the development and design of biosensors. In this paper, binding of M3 clusters (M = Au, Ag and Cu) with neutral and anionic forms of histidine amino acid was studied using density functional theory (DFT-B3LYP). It was found that the interaction of histidine with M3 clusters is governed by two major bonding factors: (a) the anchoring N-M and O-M bonds and (b) the nonconventional N-H⋯M and O-H⋯M hydrogen bonds. The nature of these chemical bonds has been investigated based on quantum theory of atoms in molecules (QTAIM) and natural bond orbital (NBO) analyses. In the next...
Interactions of glutathione tripeptide with gold cluster: Influence of intramolecular hydrogen bond on complexation behavior
, Article Journal of Physical Chemistry A ; Volume 116, Issue 17 , 2012 , Pages 4338-4347 ; 10895639 (ISSN) ; Jamshidi, Z ; Javan, M. J ; Fattahi, A ; Sharif University of Technology
2012
Abstract
Understanding the nature of the interaction between metal nanoparticles and biomolecules has been important in the development and design of sensors. In this paper, structural, electronic, and bonding properties of the neutral and anionic forms of glutathione tripeptide (GSH) complexes with a Au 3 cluster were studied using the DFT-B3LYP with 6-31+G**-LANL2DZ mixed basis set. Binding of glutathione with the gold cluster is governed by two different kinds of interactions: Auâ€"X (X = N, O, and S) anchoring bond and Au··•·•H-X nonconventional hydrogen bonding. The influence of the intramolecular hydrogen bonding of glutathione on the interaction of this peptide with the gold cluster has been...
Computational intelligence of Levenberg-Marquardt backpropagation neural networks to study the dynamics of expanding/contracting cylinder for Cross magneto-nanofluid flow model
, Article Physica Scripta ; Volume 96, Issue 5 , 2021 ; 00318949 (ISSN) ; Raja, M. A. Z ; Chu, Y. M ; Khan, W. A ; Abbas, S. Z ; Shoaib, M ; Irfan, M ; Sharif University of Technology
IOP Publishing Ltd
2021
Abstract
In the present investigation, design of integrated numerical computing through Levenberg-Marquardt backpropagation neural network (LMBNN) is presented to examine the fluid mechanics problems governing the dynamics of expanding and contracting cylinder for Cross magneto-nanofluid flow (ECCCMNF) model in the presence of time dependent non-uniform magnetic force and permeability of the cylinder. The original system model ECCCMNF in terms of PDEs is converted to nonlinear ODEs by introducing the similarity transformations. Reference dataset of the designed LMBNN methodology is formulated with Adam numerical technique for scenarios of ECCCMNF by variation of thermophoresis temperature ratio...
Fast mapping in word-learning: A case study on the humanoid social robots' impacts on Children's performance
, Article International Journal of Child-Computer Interaction ; Volume 38 , 2023 ; 22128689 (ISSN) ; Rokhi, Z ; Meghdari, A. F ; Taheri, A ; Soleymani, Z ; Alemi, M ; Karimi, M ; Sharif University of Technology
Elsevier B.V
2023
Abstract
The evolution of robotic technology has heightened the demands for robots capable of social interaction with humans, also known as social robots. The encouraging prospects of deploying this advanced assistive tool in entertainment, healthcare, and education have, in turn, promoted substantial growth in studies conducted on the human-robot interaction (HRI) topic. One hot HRI subject is the examination of social robots' efficacy within various educational scenarios, e.g., word learning. In the context of word learning, fast mapping (FM) is a well-established technique through which novel words are taught by contrasting them with previously known words. The concept of this approach originates...
Engineering quantum Hall phases in a synthetic bilayer graphene system
, Article Physical Review B ; Volume 102, Issue 8 , 2020 ; Grass, T ; Vaezi, A ; Liu, Z ; Hafezi, M ; Sharif University of Technology
American Physical Society
2020
Abstract
Synthetic quantum Hall bilayer (SQHB), realized by optically driven monolayer graphene in the quantum Hall regime, provides a flexible platform for engineering quantum Hall phases as discussed in Ghazaryan et al. [Phys. Rev. Lett. 119, 247403 (2017)PRLTAO0031-900710.1103/PhysRevLett.119.247403]. The coherent driving which couples two Landau levels mimics an effective tunneling between synthetic layers. The tunneling strength, the effective Zeeman coupling, and two-body interaction matrix elements are tunable by varying the driving frequency and the driving strength. Using infinite density matrix renormalization group techniques combined with exact diagonalization, we show that the system...
Fabrication of CuFe2O4/α-Fe2O3 composite thin films on FTO coated glass and 3-D nanospike structures for efficient photoelectrochemical water splitting
, Article ACS Applied Materials and Interfaces ; Volume 8, Issue 51 , 2016 , Pages 35315-35322 ; 19448244 (ISSN) ; Hussain, S ; Waleed, A ; Tavakoli, M. M ; Wang, Z ; Yang, S ; Fan, Z ; Nadeem, M. A ; Sharif University of Technology
American chemical society
2016
Abstract
Recently, photoelectrochemical conversion (PEC) of water into fuel is attracting great attention of researchers due to its outstanding benefits. Herein, a systematic study on PEC of water using CuFe2O4/ α-Fe2O3 composite thin films is presented. CuFe2O4/ α-Fe2O3 composite thin films were deposited on two different substrates; (1) planner FTO glass and (2) 3-dimensional nanospike (NSP). The films on both substrates were characterized and tested as anode material for photoelectrochemical water splitting reaction. During PEC studies, it was observed that the ratio between two components of composite is crucial and highest PEC activity results were achieved by 1:1 component ratio (CF-1) of...
Transmission loss allocation via loss function decomposition and current projection concept
, Article World Academy of Science, Engineering and Technology ; Volume 62 , 2010 , Pages 675-678 ; 2010376X (ISSN) ; Ghofrani, Z ; Ehsan, M ; Sharif University of Technology
2010
Abstract
One of the major problems in liberalized power markets is loss allocation. In this paper, a different method for allocating transmission losses to pool market participants is proposed. The proposed method is fundamentally based on decomposition of loss function and current projection concept. The method has been implemented and tested on several networks and one sample summarized in the paper. The results show that the method is comprehensive and fair to allocating the energy losses of a power market to its participants
An investigation on the temperature and stability behavior in the levitation melting of nickel
, Article Metallurgical and Materials Transactions B: Process Metallurgy and Materials Processing Science ; Volume 37, Issue 6 , 2006 , Pages 997-1005 ; 10735615 (ISSN) ; Halali, M ; Nusheh, M ; Sharif University of Technology
2006
Abstract
In this report the important factors affecting the levitation melting of nickel are discussed. The relationship between the temperature of a levitated sample to factors such as coil design, gas flow rate, power input, and sample weight are studied. Different coil designs were investigated and compared. It was found that for satisfactory sustained levitation melting, the sample weight, depending on the material, must be within a particular range. Furthermore, increasing the power input would result in a decrease in the droplet temperature; and increasing the weight of the sample results in an increase in the temperature. The flow rate of a cooling gas has a reverse relationship to the...
Thorough approach toward cylindrical MMW image reconstruction using sparse antenna array
, Article IET Image Processing ; Volume 12, Issue 8 , 2018 , Pages 1458-1466 ; 17519659 (ISSN) ; Seyyed Talebi, M. J ; Kazemi, M ; Kavehvash, Z ; Shabany, M
Institution of Engineering and Technology
2018
Abstract
In this study, a thorough analysis of image reconstruction in an active millimetre-wave (MMW) cylindrical imaging system is performed. To improve the system's performance in terms of the total cost as well as the coupling effect, sparse multistatic arrays are desired. Nevertheless, the existing reconstruction methods fail to operate in sparse multi-static antenna-array systems. Therefore, to address these shortcomings, in this study, at first, the existing MMW mono-static cylindrical image reconstruction methods are modified in both single-frequency and wideband reconstruction platforms. Moreover, in order to further improve the image quality and the system cost, a sparse multi-static...
Effect of electrical parameters on morphology, chemical composition, and photoactivity of the nano-porous titania layers synthesized by pulse-microarc oxidation
, Article Electrochimica Acta ; Volume 55, Issue 8 , 2010 , Pages 2760-2766 ; 00134686 (ISSN) ; Moshfegh, A. Z ; Golestani Fard, F
2010
Abstract
TiO2 layers were grown via pulse type microarc oxidation process under different applied voltages, frequencies, and duty cycles. Surface chemical composition and phase structure of the synthesized layers were studied utilizing X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). Furthermore, scanning electron microscope (SEM) and atomic force microscope (AFM) were employed to investigate surface morphology and topography of the layers. It was revealed that the layers had a porous structure with both anatase and rutile phases. The anatase relative content in the layers increased with the applied frequency; meanwhile, it decreased with duty cycle at low applied voltages, but...
A robust steganography algorithm based on texture similarity using Gabor filter
, Article 5th IEEE International Symposium on Signal Processing and Information Technology, Athens, 18 December 2005 through 21 December 2005 ; Volume 2005 , 2005 , Pages 578-582 ; Jamzad, M ; Sharif University of Technology
2005
Abstract
The main concern of steganography (image hiding) methods is to embed a secret image into a host image in such a way that the host should remain as similar as possible to its original version. In addition the host image should remain robust with respect to usual attacks. In this paper we present a method that tries to cover all above mentioned concerns. The secret and host images are divided into blocks of size 4 × 4. Each block in secret image is taken as a texture pattern for which the most similar block is found among the blocks of the host image. The embedding procedure is carried on by replacing these small blocks of the secret image with blocks in host image in such a way that least...
A review on the methods in diesel desulfurization
, Article Current Analytical Chemistry ; Volume 17, Issue 6 , 2021 , Pages 815-830 ; 15734110 (ISSN) ; Ahmad, S ; Tahir, Z ; Ul Hassan, S ; Ali, Z ; Akhtar, M. N ; Azam, K ; Abdullah, M. O ; Sharif University of Technology
Bentham Science Publishers
2021
Abstract
Background: Diesel mainly consists of paraffin and thio-aromatic compounds. Sulfur present in diesel exhaust is the major challenge for oil refineries. Sulfur is an oxidizing element that discharges as acute pollutant in the environment, having adverse effects on human and animal life. Introduction: The scope of this review paper is to discuss and highlight the recent advancements in the process of desulfurization of diesel oil to explore the less energy-intensive and more economical process. Methods: Recently, different techniques are widely used for desulfurization of diesel oil to remove sulfur containing compounds from diesel. These techniques mainly involve hydrodesulfurzation,...
Effect of intermetallic compounds on the fracture behavior of dissimilar friction stir welding joints of Mg and Al alloys
, Article International Journal of Minerals, Metallurgy and Materials ; Volume 26, Issue 10 , 2019 , Pages 1285-1298 ; 16744799 (ISSN) ; Sajuri, Z ; Selamat, N. F. M ; Omar, M. Z ; Miyashita, Y ; Kokabi, A. H ; Sharif University of Technology
University of Science and Technology Beijing
2019
Abstract
Joining Mg to Al is challenging because of the deterioration of mechanical properties caused by the formation of intermetallic compounds (IMCs) at the Mg/Al interface. This study aims to improve the mechanical properties of welded samples by preventing the fracture location at the Mg/Al interface. Friction stir welding was performed to join Mg to Al at different rotational and travel speeds. The micro structure of the welded samples showed the IMCs layers containing Al12Mg17 (γ) and Al3Mg2 (β) at the welding zone with a thickness (> 3.5
Topology and vulnerability of the Iranian power grid
, Article Physica A: Statistical Mechanics and its Applications ; Vol. 406, issue , July , 2014 , p. 24-33 ; ISSN: 03784371 ; Jalili, M ; Alipour, Z ; Sharif University of Technology
2014
Abstract
In this paper we investigated the structural properties of the ultra high voltage power transmission network of Iran. We modeled the power grid as a network with 105 nodes and 142 connection links. We found that the Iranian power grid displays a relatively moderate clustering coefficient-much larger than that of corresponding random networks-and small characteristics path length comparable to that of corresponding random networks; i.e. the power grid is a small-world network with exponential degree distribution. Global efficiency was considered as an indicator of grid's performance and the influence of random and intentional nodal failures on the efficiency was investigated. We also studied...