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    Employee commitment to innovation performance: investigating the role of knowledge acquisition and knowledge sharing

    , Article International Journal of Systematic Innovation ; Volume 7, Issue 1 , 2022 , Pages 1-17 ; 20777973 (ISSN) Sedighi, M ; Sarcheshmeh, B. S ; Bagheri, R ; Sharif University of Technology
    Society of Sytematic Innovation  2022
    Abstract
    Organisational commitment is suggested as a remarkable variable in shaping employees’ attitudes toward knowledge management practices. Customer trust in services is established during a long-time relationship with a firm and improves the accuracy of information shared with employees. To put it in other words, customer trust is what a service company needs to maintain its competitive advantage. On the other hand, high employee turnover reflects a substantial loss of knowledge. In the present study, the impact of organisational commitment on employees’ retention, knowledge acquisition, and sharing was examined regarding the moderating roles of leader-member exchange and innovation climate. The... 

    Evaluating two Model-Free data Interpertation Method for Measurments that are Influenced by Noise and Environmental Variations

    , M.Sc. Thesis Sharif University of Technology Sedighi, Sasan (Author) ; Abedian, Ali (Supervisor)
    Abstract
    Interpreting data of infrastructures monitored to detect damage of a structural is one of the most challenging issues of structural health monitoring (SHM). Especially, when environmental factors such as temperature, wind and humidity affect the data and the situation become more complicated. In this study, two methods of analysis free model of moving principal components analysis (MPCA) and robust regression analysis (RRA) have recently been considered for monitoring infrastructures compared with a variety of methods of data interpretation and results are presented. In this study, the performance of different ways in different loading conditions and arrangement of sensors have been... 

    Application of Machine Learning Algorithms on Railway Track Deterioration Modeling

    , M.Sc. Thesis Sharif University of Technology Sedighi, Alireza (Author) ; Shafahi, Yosef (Supervisor)
    Abstract
    The vital and influential role of railways in the socio-economic growth and development of countries, along with the high costs of rehabilitation and maintenance of its infrastructure, has made the existence of a comprehensive maintenance management system a necessity to not only elevate the level of service, reliability, and safety but also to minimize such repair costs. Accurate modeling of track deterioration is essential as one of the components of such systems.In this study, a large database from outputs of EM120, track recording machine, was provided for the years 2009 to 2018 and for all 18 railway zones of Iranian Railways (approximately 13,000 km railway track and 80 GB of data).... 

    Solution of the falkner-skan equation for wedge by adomian decomposition method

    , Article Communications in Nonlinear Science and Numerical Simulation ; Volume 14, Issue 3 , 2009 , Pages 724-733 ; 10075704 (ISSN) Alizadeh, E ; Farhadi, M ; Sedighi, K ; Ebrahimi Kebria, H. R ; Ghafourian, A ; Sharif University of Technology
    2009
    Abstract
    The Adomian Decomposition Method is employed in the solution of the two dimensional laminar boundary layer of Falkner-Skan equation for wedge. This work aims at the solution of momentum equation in the case of accelerated flow and decelerated flow with separation. The Adomian Decomposition Method is provided an analytical solution in the form of an infinite power series. The effect of Adomian polynomials terms is considered on accuracy of the results. The velocity profiles in boundary layer are obtained. Results show a good accuracy compared to the exact solution. © 2007 Elsevier B.V. All rights reserved  

    Switched-resistor: A new family of sampled-data circuits

    , Article AEU - International Journal of Electronics and Communications ; Volume 63, Issue 5 , 2009 , Pages 366-373 ; 14348411 (ISSN) Sedighi, B ; Bakhtiar, M. S ; Sharif University of Technology
    2009
    Abstract
    This paper introduces "switched-resistor" circuits as a new family of current-mode sampled-data circuits with improved accuracy and linearity. Advantages of the switched-resistor circuits for high-speed and low-voltage applications are demonstrated. A switched-resistor biquad band-pass filter with a quality factor of 10 and clock frequency of 100 MHz, fabricated in a 0.18 μ m CMOS process, is also presented. The filter consumes 9 mW from 1.8 V supply. © 2008 Elsevier GmbH. All rights reserved  

    Variable gain current mirror for high-speed applications

    , Article IEICE Electronics Express ; Volume 4, Issue 8 , 2007 , Pages 277-281 ; 13492543 (ISSN) Sedighi, B ; Bakhtiar, M. S ; Sharif University of Technology
    2007
    Abstract
    This paper presents a new high speed current mirror with continuous gain adjustment. Based on this current mirror, a variable gain current amplifier is designed in 0.18μm CMOS technology. The current gain of the amplifier can be continuously varied from 0 dB to 20 dB while the bandwidth of the circuit remains above 1.00 MHz. The circuit consumes 0.9 mW from 1.5V supply. © IEICE 2007  

    An 8-bit 300MS/S switched-current pipeline ADC in 0.18μm CMOS

    , Article 2007 IEEE International Symposium on Circuits and Systems, ISCAS 2007, New Orleans, LA, 27 May 2007 through 30 May 2007 ; 2007 , Pages 1481-1484 ; 02714310 (ISSN) Sedighi, B ; Sharif Bakhtiar, M ; Sharif University of Technology
    2007
    Abstract
    In this paper, capabilities of switched-current (SI) circuits are utilized to design a high-speed A/D converter. New methods to improve the performance of the SI circuits are introduced. An 8-bit 300MS/s pipeline ADC is design in 0.18um CMOS technology and an ENOB of 7.3b is obtained from simulations. The ADC consumes 40mW from a 1.8V supply. © 2007 IEEE  

    A new high-speed class-AB current-mode circuit

    , Article 2007 IEEE International Symposium on Circuits and Systems, ISCAS 2007, New Orleans, LA, 27 May 2007 through 30 May 2007 ; 2007 , Pages 717-720 ; 02714310 (ISSN) Sedighi, B ; Bakhtiar, M. S ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2007
    Abstract
    this paper presents a new class AB circuit for current-mode signal processing. The proposed circuit provides high-dynamic range, low distortion and accurate definition of quiescent current and it is well suited for high-speed applications. A third-order low-pass filter with a cutoff frequency of 200MHz and 51dB dynamic range is also presented. The Alter consumes 2.7mW from 1.8V supply. © 2007 IEEE  

    An 8-bit switched-resistor pipeline ADC

    , Article 2007 IEEE International Symposium on Circuits and Systems, ISCAS 2007, New Orleans, LA, 27 May 2007 through 30 May 2007 ; 2007 , Pages 1963-1966 ; 02714310 (ISSN) Sedighi, B ; Sharif Bakhtiar, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2007
    Abstract
    In this paper a new technique called switched-resistor is used as an alternative to switched-capacitor circuits in a low-voltage low-power high-speed A/D converter. Simulation results for an 8-bit 150MS/s pipeline ADC are presented. This converter consumes 20mW from a 1.8V supply and provides an ENOB of 7.5bit. © 2007 IEEE  

    A 1.5V 60MS/s sampled-data filter in 0.18μm CMOS

    , Article 2005 European Conference on Circuit Theory and Design, Cork, 28 August 2005 through 2 September 2005 ; Volume 2 , 2005 , Pages 95-98 ; 0780390660 (ISBN); 9780780390669 (ISBN) Sedighi, B ; Bakhtiar, M. S ; Sharif University of Technology
    2005
    Abstract
    A new family of sampled-data filters in which accuracy is a function of the ratio of the resistors is introduced. It is shown that this structure is suitable for low-voltage high-speed applications. A biquad filter with a quality factor of 10 and a clock frequency of 60MHz consuming only 2mW power is also presented  

    A new class AB current-mode circuit for low-voltage applications

    , Article APCCAS 2006 - 2006 IEEE Asia Pacific Conference on Circuits and Systems, 4 December 2006 through 6 December 2006 ; 2006 , Pages 434-437 ; 1424403871 (ISBN); 9781424403875 (ISBN) Sedighi, B ; Bakhtiar, M. S ; Sharif University of Technology
    2006
    Abstract
    This paper presents a new class AB circuit for current-mode signal processing. These current mirrors are especially designed for advanced CMOS technologies and low-voltage high-speed applications. As an example two current amplifiers with a gain of 2, settling time of less than 6ns and current consumption of 500μA are designed and simulated. ©2006 IEEE  

    Electrophoretic Deposition of Titanium Dioxide for Fabrication of Photoanode of Dye Sensitized Solar Cell

    , M.Sc. Thesis Sharif University of Technology Sedighi, Rahime (Author) ; Taghavinia, Nima (Supervisor)
    Abstract
    This research is focused on fabrication of TiO2 layers by electrophoretic deposition (EPD) for application as photoanode in Dye Sensitized Solar Cell (DSC). DSCs are third generation of solar cells, also known as the Grätzel cell, after its inventor Michael Grätzel. A DSC is composed of a porous layer of wide band gap semiconductor such as TiO2 and ZnO, covered with a molecular dye that absorbs sunlight, and a counter electrode contacted by a liquid redox electrolyte. Dye Sensitized semiconductor (photoanode) has important role in conversion of photon to electricity. To achieve higher efficiency, preparation of photoanode with high surface area resulted to enough dye adsorption is necessary.... 

    Control of human spine in repetitive sagittal plane flexion and extension motion using a CPG based ANN approach

    , Article Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS ; 2011 , Pages 8146-8149 ; 1557170X (ISSN) ; 9781424441211 (ISBN) Sedighi, A ; Sadati, N ; Nasseroleslami, B ; Vakilzadeh, M. K ; Narimani, R ; Parnianpour, M ; Sharif University of Technology
    2011
    Abstract
    The complexity associated with musculoskeletal modeling, simulation, and neural control of the human spine is a challenging problem in the field of biomechanics. This paper presents a novel method for simulation of a 3D trunk model under control of 48 muscle actuators. Central pattern generators (CPG) and artificial neural network (ANN) are used simultaneously to generate muscles activation patterns. The parameters of the ANN are updated based on a novel learning method used to address the kinetic redundancy due to presence of 48 muscles driving the trunk. We demonstrated the feasibility of the proposed method with numerical simulation of experiments involving rhythmic motion between upright... 

    Nanomedicines for hepatocellular carcinoma therapy: Challenges and clinical applications

    , Article Materials Today Communications ; Volume 34 , 2023 ; 23524928 (ISSN) Sedighi, M ; Mahmoudi, Z ; Abbaszadeh, S ; Eskandari, M. R ; Saeinasab, M ; Sefat, F ; Sharif University of Technology
    Elsevier Ltd  2023
    Abstract
    Human hepatocellular carcinoma (HCC) has been recognized as one of the significant causes of mortality around the globe. In recent years, extensive research has been carried out to find a deep-rooted perception of mechanisms involved in the pathogenesis of the disease to develop novel strategies for compassionate diagnostic and therapeutic tools. In this regard, nanotechnology has presented great opportunities in HCC diagnosis and treatment by selective and specific targeting, and efficient delivery to reach sufficient doses in targeted tumor areas without adverse influences or minimal damage to normal cells. Herein, different Nanomedicine-mediated strategies for HCC therapy are reviewed... 

    Numerical and experimental investigation of flat-plate pulsating heat pipes with extra branches in the evaporator section

    , Article International Journal of Heat and Mass Transfer ; Volume 126 , 2018 , Pages 431-441 ; 00179310 (ISSN) Sedighi, E ; Amarloo, A ; Shafii, B ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    In addition to some approaches such as changing the working fluid or number of turns in a flat-plate pulsating heat pipe (FP-PHP), geometrical changes are also appealing for enhancing the thermal performance of this type of heat pipes. The main idea of this investigation is to increase heat transfer rate by increasing flow circulation of working fluid. By placing additional branches in the evaporator section, secondary bubble pumps were created which improved the circulation of fluid inside the FP-PHP. In order to investigate the impact of these additional branches, two similar four-turn aluminum FP-PHPs were fabricated. One of them was the conventional FP-PHP and the other had four... 

    Vapor assisted deposition of alkaline doped perovskites: Pure phase formation of CsxMA1−xPbI3

    , Article Electrochimica Acta ; Volume 259 , 2018 , Pages 485-491 ; 00134686 (ISSN) Sedighi, R ; Tajabadi, F ; Taghavinia, N ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    Alkaline doping (Cs, Rb) in CH3NH3PbI3 (MAPbI3) is known to enhance the stability of perovskite solar cells. The films are usually deposited using anti-solvent method, which is tricky and not applicable for large scale deposition. Besides, in case of CsxMA1−xPbI3 the amount of Cs must be carefully controlled to prevent CsI phase formation. Herein, we report an atmospheric pressure vapor assisted solution process (AP-VASP) for the growth of Cs doped MAPbI3 perovskite films that features highly uniform morphology, pin-hole free films, large grain size, as well as being scalable. The CsxMA1−xPbI3 films are formed by the reaction of Cs doped PbI2 films with MAI vapor in a simple oven. We... 

    Dye Laser Pumped by a Second Harmonic of a Nd:YAG Laser

    , M.Sc. Thesis Sharif University of Technology Rahbari, Mohammad (Author) ; Sedighi Bonabi, Rasoul (Supervisor)
    Abstract
    The aim ofthis work is constructing a dye laser pumped in visible spectrum by a second harmonic of aNd:YAG laser.For this purpose, 12mJ of its energy focused by a cylendrical lens into a dye cell. Instead of usual telescope, making aberration in two dimensions, we have used multi prism beam expander to eliminate aberration and also expand beam beyond 10 times. The more magnification resulted in narrowing laser linewidth and it was about 2 nm for two prism beam expander and 0.5 nm for four prism beam expander.
    Beam expander configurations were designed in zero dispersioncondition.Therefore,scanning laser spectrum becomes possible. The wavelength was scanned between 565 nm to595 nm, and... 

    Optimal Wing Morphing of HALE UAV

    , M.Sc. Thesis Sharif University of Technology Sedighi, Moahammad Mahdi (Author) ; Pourtakdoust, Hossein (Supervisor)
    Abstract
    Morphing has traditionally been referred to geometric changes made to an aircraft parts and components to enhance its performance or stability. Though, the morphing concept has today developed to a broader scale and covers more than pure configuration or geometric changes. Due to importance and increasing role of HALE aircrafts in reconnaissance missions, their morphing has been recently focused by researchers. Of course, aside from its potential benefits, utility of morphing technology will increase aircraft system complexities and weight that need to be studied and compromised in design process. The present work studies optimal morphing of a HALE UAV by simultaneous analysis of... 

    Experimental Investigation ofClosed-loop Pulsating Heat-pipe with an Additional Branch in the Evaporator Section

    , M.Sc. Thesis Sharif University of Technology Sedighi, Erfan (Author) ; Shafii, Mohammad Behshad (Supervisor)
    Abstract
    The main idea of this investigation is to increase heat transfer rate by increasing flow circulation of working fluid. By placing additional branches in the evaporator section, secondary bubble pumps were created which improved the circulation of fluid inside PHP. This research was implemented in two distinct phases. In the first phase, the novelty was implemented on a single turn PHP and in the second phase, the same procedure was implemented on a 4-turn PHP. In order to investigate the impact of these additional branches, two similar heat pipes were fabricated. One of them was the conventional PHP and the other had additional branches and is named additional branch PHP (AB-PHP). Thermal... 

    Modeling And Optimization of Phase Change Materials Storage System in Greenhouse Applications

    , M.Sc. Thesis Sharif University of Technology Sedighi, Amir Saeed (Author) ; Roshandel, Ramin (Supervisor)
    Abstract
    This research develops a simulation model and algorithm to calculate the thermal demand of a one-hectare Venlo greenhouse and explores the impact of using phase change materials (PCMs) on this type of greenhouse. The algorithm controls variables like solar irradiance, artificial lighting, greenhouse humidity, carbon dioxide levels, ventilation rates, injected CO2, and shading systems, alongside greenhouse temperatures to create a system that closely mimics a real greenhouse environment. Subsequently, this model integrates with a PCM model to investigate the effects of these materials comprehensively. In this research, the heat demand of the greenhouse is calculated and compared for the...