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    Low-data complexity biclique cryptanalysis of block ciphers with application to piccolo and HIGHT

    , Article IEEE Transactions on Information Forensics and Security ; Vol. 9, Issue. 10 , 2005 , Pages 1641-1652 Ahmadi, S ; Ahmadian, Z ; Mohajeri, J ; Aref, M. R ; Sharif University of Technology
    Abstract
    In this paper, we present a framework for biclique cryptanalysis of block ciphers which extremely requires a low amount of data. To that end, we enjoy a new representation of biclique attack based on a new concept of cutset that describes our attack more clearly. Then, an algorithm for choosing two differential characteristics is presented to simultaneously minimize the data complexity and control the computational complexity. Then, we characterize those block ciphers that are vulnerable to this technique and among them, we apply this attack on lightweight block ciphers Piccolo-80, Piccolo-128, and HIGHT. The data complexity of these attacks is only 16-plaintext-ciphertext pairs, which is... 

    Synthesis, X-ray studies, and catalytic activity of tridentate Schiff base dioxo-molybdenum(VI)

    , Article Journal of Coordination Chemistry ; Volume 67, Issue 14 , 2014 ; ISSN: 00958972 Amini, M ; Khaksar, M ; Boghaei, D. M ; Bagherzadeh, M ; Ellern, A ; Woo, L. K ; Sharif University of Technology
    Abstract
    The reaction of a solution of MoO2(acac)2 in CH3OH and salicylidene 2-picoloyl hydrazone as a tridentate ONO donor Schiff base (ONO) afford a six-coordinated Mo(VI) complex [MoO2(ONO)(CH3OH)], with a distorted octahedral configuration. [MoO2(ONO)(CH3OH)] was isolated as an air-stable crystalline solid and fully characterized by single-crystal X-ray structure analysis. [MoO2(ONO)(CH3OH)] shows reactivity in the oxidation of sulfides to their corresponding sulfoxides using urea hydrogen peroxide as the oxidant at room temperature under air  

    A simple method for pulse repetition interval estimation and tracking radar pulse trains with complex pulse repetition interval modulations

    , Article Advanced Science Letters ; Volume 19, Issue 8 , 2013 , Pages 2262-2265 ; 19366612 (ISSN) Amiri, D ; Keshavarzi, M ; Amiri, K ; Sharif University of Technology
    2013
    Abstract
    In an electronic warfare environment, an electronic support system receives signals emitted by different radars. One of the key tasks in an electronic support system is PRI estimation tracking Pulse Trains using Pulse Repetition Interval (PRI) of these signals. In this paper we present a simple method for PRI estimation and tracking radar pulse trains with complex PRI Modulations. This method uses nonlinear least square, Pisarenko and innovative methods for PRI estimation and tracking pulse train. Simulation results show high robustness of the proposed method against noise (spurious and missing pulses)  

    Synthesis, X-ray studies, DFT calculations and catalytic activity of a novel iron complex containing an N, O-type bidentate oxazine ligand

    , Article Polyhedron ; Volume 61 , 2013 , Pages 94-98 ; 02775387 (ISSN) Amini, M ; Haghdoost, M. M ; Bagherzadeh, M ; Ellern, A ; Woo, L. K ; Sharif University of Technology
    2013
    Abstract
    The reactions of FeCl3·3H2O and 2-(2′-hydroxyphenyl)-5,6-dihydro-1,3-oxazine (N-O) as a bidentate O, N donor ligand afforded a five-coordinated iron(III) complex, [Fe(N-O) 2Cl], with a distorted trigonal bipyramidal configuration. The complex [Fe(N-O)2Cl] was isolated as an air-stable crystalline solid and was fully characterized, including by single-crystal X-ray structure analysis. The complex [Fe(N-O)2Cl] shows very efficient reactivity in the oxidation of sulfides to their corresponding sulfoxides using urea hydrogen peroxide (UHP) as the oxidant at room temperature under air. To get an insight into the electronic structure of the complex, the experimental studies have been accompanied... 

    Catalytic efficacy of an oxido-peroxido tungsten(VI) complex: Synthesis, X-ray structure and oxidation of sulfides and olefins

    , Article Journal of Coordination Chemistry ; Volume 66, Issue 11 , Jan , 2013 , Pages 1897-1905 ; 00958972 (ISSN) Amini, M ; Bagherzadeh, M ; Eftekhari Sis, B ; Ellern, A ; Woo, L. K ; Sharif University of Technology
    2013
    Abstract
    An oxido-peroxido tungsten(VI) complex [WO(O2)L(CH 30H)] using salicylidene benzoyl hydrazine as a tridentate ONO donor Schiff base (H2L) has been synthesized and characterized by elemental analysis, IR, 1H NMR, molar conductance data, and single-crystal X-ray analysis. The complex was used as a catalyst for epoxidation of olefins and oxidation of sulfides. The results show that epoxides and sulfoxides were produced in high yield, turnover number, and selectivity  

    Selective oxidation of sulfides and olefins by a manganese (III) complex containing an N,O-type bidentate oxazine ligand

    , Article Journal of Coordination Chemistry ; Volume 66, Issue 3 , 2013 , Pages 464-472 ; 00958972 (ISSN) Amini, M ; Bagherzadeh, M ; Moradi-Shoeili, Z ; Boghaei, D. M ; Ellern, A ; Woo, L. K ; Sharif University of Technology
    2013
    Abstract
    A new manganese(III) complex [(N-O)2Mn(OAc)] was synthesized using 2-(2'-hydroxyphenyl)-5,6-dihydro-1,3-oxazine (N-O) as a bidentate O, N donor. The complex has been characterized by elemental analysis, IR, UV-vis spectroscopy, and X-ray structure analysis. Oxidation of sulfides and epoxidation of olefins, respectively, to their corresponding sulfoxides and epoxides were conducted by this catalyst using urea hydrogen peroxide as oxidant at room temperature under air. The catalyst is efficient in oxidation reactions giving high yields and selectivities  

    Synthesis, X-ray structure and oxidation catalysis of a oxido-peroxido molybdenum(VI) complex with a tridentate Schiff base ligand

    , Article Inorganic Chemistry Communications ; Volume 20 , 2012 , Pages 86-89 ; 13877003 (ISSN) Bagherzadeh, M ; Amini, M ; Parastar, H ; Jalali Heravi, M ; Ellern, A ; Woo, L. K ; Sharif University of Technology
    2012
    Abstract
    A new oxido-peroxido molybdenum(VI) complex [MoO(O 2)L(CH 3OH)] was synthesized, using salicylidene benzoyl hydrazine as tridentate ONO donor Schiff base ligand (H 2L). The complex has been characterized by elemental analysis, IR, 1H NMR, molar conductance data, and finally by X-ray structure analysis. This complex functions as facile olefin epoxidation catalyst with hydrogen peroxide (H 2O 2) as terminal oxidant and sodium hydrogen carbonate (NaHCO 3) as a co-catalyst at room temperature. Catalytic potentiality of complex is also exhibited in oxidation of sulfides. The catalyst show very much efficient reactivity in the oxidation reactions giving high yield, turnover number (TON) and... 

    Synthesis, spectral characterization and crystal structure studies of a new hydrazone Schiff base and its dioxomolybdenum(VI) complex

    , Article Journal of Coordination Chemistry ; Volume 68, Issue 8 , Feb , 2015 , Pages 1441-1451 ; 00958972 (ISSN) Kia, R ; Kargar, H ; Sharif University of Technology
    Taylor and Francis Ltd  2015
    Abstract
    A new hydrazone-Schiff base (H2L) and it corresponding dioxomolybdenum(VI) complex were synthesized and characterized by spectroscopic methods and elemental analyses. The crystal structures of both ligand and its complex were determined by single-crystal X-ray diffraction. A new hydrazone Schiff base, (E)-N′-(3-ethoxy-2-hydroxybenzylidene)isonicotinohydrazide (H2L), has been prepared and characterized by elemental analyses, spectroscopic methods, and single-crystal X-ray diffraction. The corresponding dioxomolybdenum(VI) complex [Mo(O)2(L)(CH3OH)] was synthesized and characterized by spectroscopic methods and by single-crystal X-ray diffraction. The hydrazone ligand coordinates to Mo through... 

    Temperature gradient and wind profile effects on heavy gas dispersion in build up area

    , Article Journal of Applied Sciences Research ; Volume 6, Issue 12 , 2010 , Pages 6010-6020 ; 1816157X (ISSN) Kashi, E ; Shahraki, F ; Rashtchian, D ; Behzadmehr, A ; Sharif University of Technology
    Abstract
    Dispersion of heavy gases is considered to be more hazardous than the passive ones. This is because it takes place more slowly. In this paper, based on the extensive experimental work of Hanna and Chang, the CFD model (Ansys-CFX) was tested compared with Kit Fox experiments. In order to accomplish this validation, the multiphase approach was employed as a new method in this area. In addition, the temperature gradient effects were investigated. The survey of wind speed was done taking factors such as time, height and direction into the consideration. To reduce the number of elements in computational domain, a combination of 2D and 3D geometries were utilized. Results showed that the wind... 

    Temperature gradient and wind profile effects on heavy gas dispersion in build up area

    , Article Australian Journal of Basic and Applied Sciences ; Volume 4, Issue 12 , 2010 , Pages 6010-6020 ; 19918178 (ISSN) Kashi, E ; Shahraki, F ; Rashtchian, D ; Behzadmehr, A ; Sharif University of Technology
    Abstract
    Dispersion of heavy gases is considered to be more hazardous than the passive ones. This is because it takes place more slowly. In this paper, based on the extensive experimental work of Hanna and Chang, the CFD model (Ansys-CFX) was tested compared with Kit Fox experiments. In order to accomplish this validation, the multiphase approach was employed as a new method in this area. In addition, the temperature gradient effects were investigated. The survey of wind speed was done taking factors such as time, height and direction into the consideration. To reduce the number of elements in computational domain, a combination of 2D and 3D geometries were utilized. Results showed that the wind... 

    A new vanadium Schiff base complex as catalyst for oxidation of alcohols

    , Article Journal of Coordination Chemistry ; Volume 63, Issue 21 , May , 2010 , Pages 3849-3858 ; 00958972 (ISSN) Bagherzadeh, M ; Amini, M ; Sharif University of Technology
    2010
    Abstract
    The monoanionic bidentate Schiff base, N-(phenolyl)-benzaldimine (HL), has been employed to synthesize a new vanadium(IV) complex of general composition [VO(L)2] (where L = O, N donor of Schiff base). The ligand and complex have been fully characterized by elemental analyses, molar conductance data, FT-IR, 1H- and 13C-NMR, and UV-Vis spectroscopies. Oxidation of alcohols to their corresponding aldehydes and ketones was conducted by this complex catalyst using Oxone as oxidant under biphasic reaction conditions (CH2Cl2/H2O) and tetra-n-butylammonium bromide as phase transfer agent under air at room temperature  

    Weighted coupling for geographical networks: Application to reducing consensus time in sensor networks

    , Article Physics Letters, Section A: General, Atomic and Solid State Physics ; Volume 374, Issue 38 , 2010 , Pages 3920-3925 ; 03759601 (ISSN) Jalili, M ; Mazloomian, A ; Sharif University of Technology
    2010
    Abstract
    Although many complex real-world networks are weighted, unweighted networks are used in many applications such as sensor networks. In this Letter it is shown using properly weighted networks the performance can be greatly enhanced by reducing the time necessary for the average consensus. Random geographical models are adapted as network models and a method based on mutually coupled phase oscillators is used for providing average consensus over the network. The consensus time is calculated by numerically solving the network's differential equations and monitoring the average error. The simulation results on some sample networks show that the consensus time is dramatically reduced when the... 

    DFT study on metal cationization and o6-protonation on 2'-deoxyguanosine configuration: Changes on sugar puckering and strength of the n-glycosidic bond

    , Article Journal of Theoretical and Computational Chemistry ; Volume 9, Issue 3 , June , 2010 , Pages 585-609 ; 02196336 (ISSN) Ahmadi, M. S ; Fattahi, A ; Sharif University of Technology
    2010
    Abstract
    Density functional theory (DFT) calculations were performed at the B3LYP/6-311++G(d, p) level to determine coordination geometries, absolute metal ion affinities, and free energies for all possible complexation stable products formed by monovalent metal cations including Li+, Na+, K+ with the nucleoside 2'-Deoxyguanosine. All computations indicate that the metal ion affinity (MIA) decreases on going from Li+ to Na+ and K+ for 2'-Deoxyguanosine. For example, the affinities for the metal ions described above are 75.2, 57.3, 43.4 kcal/mol, respectively. Furthermore, the influence of metal cationization and O 6 protonation on the strength of the N-glycosidic bond, torsion angles and angle of... 

    Cycloplatinated(II) complexes containing bridging bis(diphenylphosphino)acetylene: Photophysical study

    , Article Journal of Luminescence ; Volume 179 , 2016 , Pages 222-229 ; 00222313 (ISSN) Jamshidi, M ; Nabavizadeh, S. M ; Sepehrpour, H ; Niroomand Hosseini, F ; Kia, R ; Rashidi, M ; Sharif University of Technology
    Elsevier  2016
    Abstract
    Reaction of the known cycloplatinated (II) complexes [PtAr(C^N)(SMe2)], in which Ar=p–MeC6H4 or p–MeOC6H4 and C^N= 2-phenylpyridinate (ppy) or benzo[h]quinolinate (bhq), with 0.5 equivalent of the bidentate phosphine ligand 1,1′–bis(diphenylphosphino)acetylene, dppac, in acetone at room temperature gave the symmetrical binuclear cycloplatinated(II) complexes [Pt2Ar2(C^N)2(μ–dppac)], 1–4, in which dppac acts as a bridging bidentate ligand. All the complexes were fully characterized using multinuclear (1H, 31P and 195Pt) NMR spectroscopy and the complex [Pt2(p–MeC6H4)2(ppy)2(μ–dppac)], 1, was further identified by single crystal X-ray structure determination. Additional information about the... 

    Synthesis, characterization, and catalytic activity of supported molybdenum Schiff base complex as a magnetically recoverable nanocatalyst in epoxidation reaction

    , Article Journal of Coordination Chemistry ; Volume 69, Issue 4 , 2016 , Pages 668-677 ; 00958972 (ISSN) Moradi Shoeili, Z ; Zare, M ; Bagherzadeh, M ; Ozkar, S ; Akbayrak, S ; Sharif University of Technology
    Taylor and Francis Ltd  2016
    Abstract
    A heterogeneous nanocatalyst was prepared via covalent anchoring of dioxomolybdenum(VI) Schiff base complex on core-shell structured Fe3O4@SiO2. The properties and the nature of the surface-fixed complex have been identified by a series of characterization techniques such as SEM, EDX, XRD, TGA, FT-IR, and VSM. The synthesized hybrid material was an efficient nanocatalyst for selective oxidation of olefins to corresponding epoxides with t-BuOOH in high yields and selectivity. The catalyst could be conveniently recovered by applying an external magnetic field and reused several times without significant loss of efficiency. © 2016 Taylor and Francis  

    ONO pincer type binuclear Pd(II) complex: Synthesis, crystal structure and catalytic utilization of the resulting organopalladium complex in catalytic copper-free Sonogashira coupling reaction

    , Article Inorganica Chimica Acta ; Volume 451 , 2016 , Pages 227-232 ; 00201693 (ISSN) Bagherzadeh, M ; Mousavi, N. A ; Zare, M ; Jamali, S ; Ellern, A ; Woo, L. K ; Sharif University of Technology
    Elsevier S.A  2016
    Abstract
    New binuclear palladium (II) complex featuring ONO pincer type hydrazone ligand was synthesized and characterized by spectroscopic and single-crystal XRD analysis. This complex showed excellent catalytic activity towards the copper-free Sonogashira cross coupling reaction. The main advantages over previous methodologies include low catalyst loading, less problematic reaction media (H2O–DMSO) and reusability in homogenous systems for optimal performance  

    Path simplification under difference area measure

    , Article 2009 14th International CSI Computer Conference, CSICC 2009, 20 October 2009 through 21 October 2009, Tehran ; 2009 , Pages 276-279 ; 9781424442621 (ISBN) Daneshpajouh, S ; Zarei, A ; Ghodsi, M ; Sharif University of Technology
    Abstract
    In this paper, we consider path simplification problem under difference area (diff-area) measure. Diff-area measure is defined as AA(Q) AB(Q) , where AA(Q) is the area under Q and above P and AB(Q) is the area above Q and under P (sec Figure 1). Bose et al. [1] presented an approximation algorithm for finding a simplificd path with at most k verticcs that minimizes the cliff-area measure which only works on i-monotone paths. The constraint of being i-monotone is restrictive in some applications like tracking bird migration paths or map boundary simplification. Here, we extend the method of Rosc et al. [1] and present algorithms with the same time complexities as theirs for gcneral paths.... 

    On the possibility of network scheduling with polynomial complexity and delay

    , Article IEEE/ACM Transactions on Networking ; 2017 ; 10636692 (ISSN) Sharifnassab, A ; Golestani, S. J ; Sharif University of Technology
    Abstract
    Considering the collection of all networks with independent set interference model, Shah, Tse, and Tsitsiklis showed that there exist scheduling algorithms with polynomial complexity and delay, only if the maximum independent set problem can be solved in polynomial time (equivalently, P=NP). In this paper, we extend this result to arbitrary collections of networks and present a clear-cut criterion for the existence of polynomial complexity and delay scheduling algorithms relative to a given collection of networks with arbitrary interference models, not confined to independent set interference or SINR models, and not necessarily encompassing all network topologies. This amounts to the... 

    The value of help bits in randomized and average-case complexity

    , Article Computational Complexity ; Volume 26, Issue 1 , 2017 , Pages 119-145 ; 10163328 (ISSN) Beigi, S ; Etesami, O ; Gohari, A ; Sharif University of Technology
    Birkhauser Verlag AG  2017
    Abstract
    “Help bits" are some limited trusted information about an instance or instances of a computational problem that may reduce the computational complexity of solving that instance or instances. In this paper, we study the value of help bits in the settings of randomized and average-case complexity. If k instances of a decision problem can be efficiently solved using ℓ< k help bits, then without access to help bits one can efficiently compute a k-bit vector that is not equal to the k-bit vector of solutions to the k instances. A decision problem with this property is called k-membership comparable. Amir, Beigel, and Gasarch (1990) show that for constant k, all k-membership comparable languages... 

    Link prediction in multiplex online social networks

    , Article Royal Society Open Science ; Volume 4, Issue 2 , 2017 ; 20545703 (ISSN) Jalili, M ; Orouskhani, Y ; Asgari, M ; Alipourfard, N ; Perc, M ; Sharif University of Technology
    Royal Society  2017
    Abstract
    Online social networks play a major role in modern societies, and they have shaped the way social relationships evolve. Link prediction in social networks has many potential applications such as recommending new items to users, friendship suggestion and discovering spurious connections. Many real social networks evolve the connections in multiple layers (e.g. multiple social networking platforms). In this article, we study the link prediction problem in multiplex networks. As an example, we consider a multiplex network of Twitter (as a microblogging service) and Foursquare (as a location-based social network). We consider social networks of the same users in these two platforms and develop a...