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    Effects of diverging angle and fuel molecular weight on NOx emissions in converging and diverging ducts

    , Article Journal of Engineering Research ; Volume 1, Issue 3 , 2013 , Pages 161-179 ; 23071885 (ISSN) Moghiman, M ; Amiri, M ; Amiri, A ; Sharif University of Technology
    The present paper developed and validated a numerical procedure for the calculation of turbulent combustive flows in converging and diverging ducts. Through simulation of the heat transfer processes, the amounts of production and spread of NOx pollutants were measured. Also, this paper reported the results of a numerical investigation of the effects of the fuel Molecular Weight on NOx emissions in converging and diverging ducts. The fuels which were examined were methane, naphtha, and kerosene. The differential equations in the Von-Misses coordinate system were transformed to a cross-stream coordinate system in order to concentrate more grid lines near wall boundaries. A marching integration... 

    Voltammetric determination of thiocytosine based on its electrocatalytic oxidation on the surface of carbon-paste electrode modified with cobalt schiff base complexes

    , Article Journal of Solid State Electrochemistry ; Volume 11, Issue 8 , 2007 , Pages 1133-1138 ; 14328488 (ISSN) Shahrokhian, S ; Amiri, M ; Sharif University of Technology
    The electrochemical oxidation of thiocytosine on the surface of carbon-paste electrode modified with Schiff base (salophen derivatives) complexes of cobalt is studied. The effect of the substituents in the structure of salophen on the catalytic property of the modified electrode is investigated by using cyclic and differential pulse voltammetry. Cobalt (II)-5-nitrosalophen, because of its electrophilic functional groups, leads to a considerable enhancement in the catalytic activity, sensitivity (peak current), and a marked increase in the anodic potential of the modified electrode. The differential pulse voltammetry is applied as a very sensitive method for the detection of thiocytosine. The... 

    Multi-walled carbon nanotube paste electrode for selective voltammetric detection of isoniazid

    , Article Microchimica Acta ; Volume 157, Issue 3-4 , 2007 , Pages 149-158 ; 00263672 (ISSN) Shahrokhian, S ; Amiri, M ; Sharif University of Technology
    A multi-walled carbon nanotube paste electrode (MWCPE) is prepared as an electrochemical sensor with high sensitivity and selectivity in responding to isoniazid. The electrochemical oxidation of isoniazid is investigated in buffered solution by cyclic and differential pulse voltammetry. The electrode is shown to be very effective for the detection of isoniazid in the presence of other biological reductant compounds. The electrochemical oxidation of cysteine, due to the high overvoltage, is completely stopped at the surface of MWCPE. The electrode exhibits a very good resolution between the voltammetric peak of isoniazid and the peaks of ascorbic acid (AA) and dopamine (DA). A resolution of... 

    Nucleophilic addition of thiaproline to electrochemically derived o-quinone, application to the sensitive voltammetric detection of thiaproline

    , Article Electroanalysis ; Volume 18, Issue 22 , 2006 , Pages 2225-2231 ; 10400397 (ISSN) Shahrokhian, S ; Amiri, M ; Sharif University of Technology
    The mechanism of electrochemical behavior of catechol in the presence of thiaproline is investigated by cyclic voltammetry, controlled-potential coulometry and spectrophotometric tracing of the reaction coordinate. The results indicate that thiaproline participate in with an ECEC mechanism in a nucleophilic (Michael) addition to o-quinone. Effect of pH of buffer solution on reaction pathway is studied and showed that addition of thiaproline to the o-quinone is performed only in solutions with pHs higher than 5. These results indicate that the addition of thiaproline is occurred first from amine functional group. In the second step, the addition of carboxylate group of thiaproline to C-5 of... 

    Mercaptotriazole as a nucleophile in addition to o-quinone electrochemically derived from catechol: Application to electrosynthesis of a new group of triazole compounds

    , Article Electrochemistry Communications ; Volume 7, Issue 1 , 2005 , Pages 68-73 ; 13882481 (ISSN) Shahrokhian, S ; Amiri, M ; Sharif University of Technology
    Electrochemical oxidation of catechol in the presence of 3-mercapto-1,2,4-triazole (MTA) as a nucleophile in aqueous buffered solutions was studied by cyclic voltammetry and controlled-potential coulometry. The mechanism of electrochemical reaction is confirmed by spectrophotometric tracing in various times of controlled-potential coulometry. The voltammetric and spectrophotometric foundations indicate that a 1,4 Michael addition of MTA from its thiol moiety to the electrochemically derived o-quinone is occurred. The electrochemical synthesis of Michael addition product has been successfully accomplished by controlled-potential coulometry in a divided H-type cell and the reaction product was... 

    Visible photoenhanced current-voltage characteristics of Au : TTT iO2 nanocomposite thin films as photoanodes

    , Article Journal of Physics D: Applied Physics ; Volume 43, Issue 10 , 2010 ; 00223727 (ISSN) Naseri, N ; Amiri, M ; Moshfegh, A. Z ; Sharif University of Technology
    In this investigation, the effect of annealing temperature and concentration of gold nanoparticles on the photoelectrochemical properties of sol-gel deposited Au : TiO2 nanocomposite thin films is studied. Various gold concentrations have been added to the TiO2 thin films and their properties are compared. All the deposited samples are annealed at different temperatures. The optical density spectra of the films show the formation of gold nanoparticles in the films. The optical bandgap energy of the Au : TiO2 films decreases with increasing Au concentration. The crystalline structure of the nanocomposite films is studied by x-ray diffractometry indicating the formation of gold nanocrystals in... 

    A low overhead fault detection and recovery method for the faults in clock generators

    , Article 2009 IEEE Circuits and Systems International Conference on Testing and Diagnosis, ICTD'09, Chengdu, 28 April 2009 through 29 April 2009 ; 2009 ; 9781424425877 (ISBN) Karimpour Darav, N ; Amiri, M. A ; Ejlali, A ; Sharif University of Technology
    In many synchronous digital systems especially those used in mobile applications, the system is exposed to sever shaking that may lead to a failure in the clock generator. In this paper we present an effective method to tolerate the faults on the clock signal that are due to defects in external oscillators. Our technique utilizes no Phase-Lock Loops (PLL), no Delay-Locked Loops (DLL) and no high frequency oscillators because of their drawbacks so that it needs neither more effort to meet Electro-Magnetic Compatibility (EMC) and requirements nor extra hardware to implement DLLs. We have formally evaluated the meta-stability of our technique. This evaluation shows that our technique reliably... 

    Mapping activity diagram to Petri Net: Application of Markov theory for analyzing non-functional parameters

    , Article International Journal of Engineering, Transactions B: Applications ; Volume 20, Issue 1 , 2007 , Pages 65-76 ; 1728-144X (ISSN) Motameni, H ; Movaghar, A ; Fadavi Amiri, M ; Sharif University of Technology
    Materials and Energy Research Center  2007
    The quality of an architectural design of a software system has a great influence on achieving non-functional requirements of a system. A regular software development project is often influenced by non-functional factors such as the customers' expectations about the performance and reliability of the software as well as the reduction of underlying risks. The evaluation of non- functional parameters of a software system at the early stages of design and its development process are often considered as major factors in dealing with these issues. Because these evaluations can help us to choose the most proper model which is the securest and the most reliable.In this paper, a method is presented... 

    Markhor: malware detection using fuzzy similarity of system call dependency sequences

    , Article Journal of Computer Virology and Hacking Techniques ; 2021 ; 22638733 (ISSN) Lajevardi, A. M ; Parsa, S ; Amiri, M. J ; Sharif University of Technology
    Springer-Verlag Italia s.r.l  2021
    Static malware detection approaches are time-consuming and cannot deal with code obfuscation techniques. Dynamic malware detection approaches, on the other hand, address these two challenges, however, suffer from behavioral ambiguity, such as the system calls obfuscation. In this paper, we introduce Markhor, a dynamic and behavior-based malware detection approach. Markhor uses system call data dependency and system call control dependency sequences to create a weighted list of malicious patterns. The list is then used to determine the malicious processes. Next, the similarity of a file system call sequences to a malicious pattern is extracted based on a fuzzy algorithm and the file nature is... 

    Effect of annealing temperature on growth of Ce-ZnO nanocomposite thin films: X-ray photoelectron spectroscopy study

    , Article Thin Solid Films ; Volume 520, Issue 2 , November , 2011 , Pages 721-725 ; 00406090 (ISSN) Yousefi, M ; Azimirad, R ; Amiri, M ; Moshfegh, A. Z ; Sharif University of Technology
    Ce-doped ZnO nanocomposite thin films with Ce/Zn ratio fixed at optimum value (10 at.%) have been prepared via sol-gel method at different annealing temperatures varied from 180 to 500 °C. The synthesized samples were characterized employing atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) techniques. According to AFM analysis, the average grain size increased from about 70 nm to 150 nm by increasing the annealing temperature from 300 to 500 °C. Moreover, based on the XPS data analysis, it was found that three major metal ions namely Ce 3+, Ce4+, and Zn2+ coexist on the surface of the nanocomposite films. XPS data analysis also revealed that... 

    Enhanced photoelectrochemical activity of Ce doped ZnO nanocomposite thin films under visible light

    , Article Journal of Electroanalytical Chemistry ; Volume 661, Issue 1 , 2011 , Pages 106-112 ; 15726657 (ISSN) Yousefi, M ; Amiri, M ; Azimirad, R ; Moshfegh, A. Z ; Sharif University of Technology
    Ce-doped ZnO and pure ZnO nanocomposite thin films with different Ce/Zn ratios (0, 2, 5, 10, 15, 20, and 30 at.%) have been prepared by sol-gel method at optimum annealing temperature of 500 °C. The synthesized samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV-vis spectrophotometry. According to our XPS data analysis, there are three major metal ions namely Ce3+, Ce4+ and Zn 2+ that coexist on the surface. The XRD measurements indicate that the ZnO thin films have a hexagonal wurtzite structure, and CeO2 crystallites formed in the Ce-doped ZnO nanocomposite thin films. Photoelectrochemical property of the samples was studied by three... 

    Towards a goal-driven method for web service choreography validation

    , Article 2016 2nd International Conference on Web Research, ICWR 2016, 27 April 2016 through 28 April 2016 ; 2016 , Pages 66-71 ; 9781509021666 (ISBN) Parsa, S ; Ebrahimifard, A ; Amiri, M. J ; Khoramabadi Arani, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2016
    Nowadays web services composition that presents capabilities in response to customers' complex requirements has a special importance in real businesses. However, service choreography as a form of service composition, still faces many challenges. One of the most important challenges of the choreography domain is how to validate the model based on the corresponding requirements. To this end, in this paper processes choreographies are modeled using the interaction view of BPMN 2.0 standard. Then, goal modeling is suggested to extract the requirements. For each requirement all possible valid scenarios are considered and finally using Savara tool, the requirements' scenarios are modeled and the... 

    Evaluation of babbling idiot failures in FlexRay-based networkes

    , Article IFAC Proceedings Volumes (IFAC-PapersOnline) ; Volume 7, Issue PART 1 , 2007 , Pages 399-406 ; 14746670 (ISSN); 9783902661340 (ISBN) Lari, V ; Dehbashi, M ; Miremadi, S. G ; Amiri, M ; Sharif University of Technology
    IFAC Secretariat  2007
    This paper evaluates the error propagation and its effects in babbling idiot failure in a FlexRay-based network. The evaluation is based on about 35680 bit-flip fault injections inside different parts of the FlexRay communication controller. To do this, a FlexRay communication controller is modeled by Verilog HDL at the behavioral level. Then, this controller is exploited to setup a FlexRay-based network composed of four nodes. Nodes in this experiment are considered in two forms: 1) node without bus guardian, 2) node with bus guardian. The results of fault injection show that in first form about 4.57% of faults lead to the babbling idiot failures. Also in second form about 0.75% faults lead... 

    A sequential approach for hybridizing conventional vehicles and an approval example

    , Article 8th Biennial ASME Conference on Engineering Systems Design and Analysis, ESDA2006, Torino, 4 July 2006 through 7 July 2006 ; Volume 2006 , 2006 ; 0791837793 (ISBN); 9780791837795 (ISBN) Esfahanian, M ; Khanipour, A ; Nabi, A ; Fazeli, A. M ; Amiri, M ; Sharif University of Technology
    American Society of Mechanical Engineers  2006
    Hybridization of conventional vehicles is considered an important step to achieve high fuel economy and low emissions. In this study, principle considerations involved in a hybridizing process are discussed and consequently, a sequential approach for designing hybrid components for both series and parallel configurations has been introduced. The so called approach has then been applied to one of the productions of Iran-Khodro Company called SAMAND. Having designed the hybrid components, the conventional SAMAND and its series and parallel hybrid configurations were defined and evaluated using the ADvanced VehIcle SimulatOR (ADVISOR) software. It is observed that compared to the conventional... 

    Development of energy management system for A parallel hybrid electric vehicle using fuzzy logic

    , Article 8th Biennial ASME Conference on Engineering Systems Design and Analysis, ESDA2006, Torino, 4 July 2006 through 7 July 2006 ; Volume 2006 , 2006 ; 0791837793 (ISBN); 9780791837795 (ISBN) Fazeli, A. M ; Nabi, A ; Salmasi, F. R ; Amiri, M ; Sharif University of Technology
    In this paper a fuzzy power controller for a parallel hybrid passenger car is developed in order to minimize its fuel consumption and optimize its components efficiencies. This is done by controlling the engine operating points in its optimal region and maintaining the SoC of batteries and electric motor operating point at the highest possible efficiency. Of course the designed control strategy must be able to obey the driver's commands and achieve the PNGV regulations. The controller implemented in this paper is a Mamdani fuzzy logic controller which takes the batteries SoC, electric motor's speed, ICE speed and the total demanded torque as its input variables and gives the ICE torque as... 

    Structure, texture and magnetic properties of laser-welded ultrathin Fe-Co-V foils

    , Article Acta Metallurgica Sinica (English Letters) ; Volume 28, Issue 3 , March , 2015 , Pages 338-347 ; 10067191 (ISSN) Mostaan, H ; Shamanian, M ; Monirvaghefi, S. M ; Behjati, P ; Szpunar, J. A ; Amiri, M ; Fathi Moghadam, M ; Sharif University of Technology
    Chinese Society for Metals  2015
    This research aims to investigate the effect of pulsed Nd:YAG laser micro-welding on the microstructure, texture and magnetic properties of ultra-thin Fe-Co-7.15 wt% V magnetic alloy. Optical microscopy, scanning electron microscopy and electron backscattered diffraction techniques were used to study the microstructural evolutions. Also, vibrating sample magnetometry was used to characterize the magnetic properties. The results showed that the fractions of low Σ coincidence site lattice boundaries in the fusion zone are higher than those of the base metal. The welded samples experience a significant decrease in their magnetic properties. It was found that the formation of new fiber texture... 

    Thermoplastic starch/ethylene vinyl alcohol/forsterite nanocomposite as a candidate material for bone tissue engineering

    , Article Materials Science and Engineering C ; Volume 69 , 2016 , Pages 301-310 ; 09284931 (ISSN) Mahdieh, Z ; Bagheri, R ; Eslami, M ; Amiri, M ; Shokrgozar, M. A ; Mehrjoo, M ; Sharif University of Technology
    Elsevier Ltd 
    Recently, biodegradable polymers such as starch based blends have been well renowned in the biomedical field. Studies have considered them suitable for bone scaffolds, bone cements, tissue engineering scaffolds, drug delivery systems and hydrogels. The aim of this study was to synthesize nanocomposite biomaterial consisting a blend of thermoplastic starch and ethylene vinyl alcohol as the polymer matrix, and nano-structured forsterite as the ceramic reinforcing phase for bone tissue engineering applications. Furthermore, vitamin E was applied as a thermal stabilizer during melt compounding. Extrusion and injection molding were incorporated for melt blending and shaping of samples,... 

    Enhanced electrochemical hydrogen storage by catalytic Fe-doped multi-walled carbon nanotubes synthesized by thermal chemical vapor deposition

    , Article Journal of Power Sources ; Volume 188, Issue 2 , 2009 , Pages 404-410 ; 03787753 (ISSN) Reyhani, A ; Mortazavi, S.Z ; Moshfegh, A.Z ; Golikand, A.N ; Amiri, M ; Sharif University of Technology
    Hydrogen storage capacities of raw, oxidized, purified and Fe-doped multi-walled carbon nanotubes (MWCNTs) were studied by electrochemical method. Based on transmission electron microscopy and Raman spectroscopic data, thermal oxidation removed defective graphite shells at the outer walls of MWCNTs. The analysis results indicated that the acid treatment dissolved most of the catalysts and opened some tips of the MWCNTs. Thermal gravimetric analysis and differential scanning calorimetry results illustrated that by oxidation and purification of MWCNTs, the weight loss peak shifts toward a higher temperature. N2 adsorption isotherms of the purified and oxidized MWCNTs showed an increase in N2... 

    Modified joint channel-and-data estimation for one-bit massive MIMO

    , Article 53rd IEEE International Symposium on Circuits and Systems, ISCAS 2021, 22 May 2021 through 28 May 2021 ; Volume 2021-May , 2021 ; 02714310 (ISSN); 9781728192017 (ISBN) Bahari, M ; Rasoulinezhad, Ramin ; Amiri, M ; Gilani, F ; Saadatnejad, S ; Nezamalhosseini, A. R ; Shabany, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2021
    Centralized and cloud computing-based network architectures are the promising tracks of future communication systems where a large scale compute power can be virtualized for various algorithms. These architectures rely on high-performance communication links between the base stations and the central computing systems. On the other hand, massive Multiple-Input Multiple-Output (MIMO) technology is a promising solution for base stations toward higher spectral efficiency. To reduce system complexity and energy consumption, 1-bit analog-to-digital converters (ADCs) are leveraged with the cost of lowering the signal quality. To recover the lost information, more sophisticated algorithms, like... 

    A quantization noise robust object's shape prediction algorithm

    , Article 13th European Signal Processing Conference, EUSIPCO 2005, Antalya, 4 September 2005 through 8 September 2005 ; 2005 , Pages 1770-1773 ; 1604238216 (ISBN); 9781604238211 (ISBN) Khansari, M ; Rabiee, H. R ; Asadi, M ; Nosrati, M ; Amiri, M ; Ghanbari, M ; Sharif University of Technology
    This paper introduces a quantization noise robust algorithm for object's shape prediction in a video sequence. The algorithm is based on pixel representation in the undecimated wavelet domain for tracking of the user-defined shapes contaminated by the compression noise of video sequences. In the proposed algorithm, the amplitude of coefficients in the best basis tree expansion of the undecimated wavelet packet transform is used as feature vectors (FVs). FVs robustness against quantization noise has been achieved through inherent denoising and edge component separation in the best basis selection algorithm. The algorithm uses these FVs to track the pixels of small square blocks located at the...