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shirvani--sara
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Statistical Analysis of Parameter Fluctuation on Performance of Giga Scale Integration
, M.Sc. Thesis Sharif University of Technology ; Sarvari, Reza (Supervisor)
Abstract
Developing to the sub-micron dimentions reduces the size of integrated circuits, so interconnects and a variations in their characteristics has more effects on circuit performance. Worst case study is the most common method in these systems, but in many cases interconnect lines are independent from eachother. Analysis state that worst case is out of the distribution in many cases (with zero possibility) and result in a pessimistic design. Statistical analysis should replace worst case analysis in multi varient systems. In this titile, statistical analysis will be used to investigate performance of interconnects in new technology. Maximum variation in interconnect parameters are considered...
Synthesis and Characterization of Electrospun N/S Doped ZnO and Investigation of their Applications in Dye Degradation
, M.Sc. Thesis Sharif University of Technology ; Poujavadi, Ali (Supervisor)
Abstract
In this research, the synthesis of the electrospum nano fiber doped zinc oxide and its photocatalyst usage was investigated. The band gap of the zinc oxide in the area of UV leads to deactivation of this material at the visible light. With due the attention to sunny weather in Iran and the fact that about 50 percentage of sunlight is visible light, producing and usage of catalyst materials actived at visible light is economical. Doping is one of the ways of activating ZnO at visible light, so in this research thiourea is used as the source of ZnO doping. The results of the expriments done at visible light and also spectrums of DRS, XPS and XRD prove that the doping is happened. Also, in this...
Integration of a Cyclic Three-Stage Supply Chain for Fast Moving Consumer Goods
, Ph.D. Dissertation Sharif University of Technology ; Shadrokh, Shahram (Supervisor)
Abstract
This research deals with a realistic cyclic three-stage supply chin consisting of one supplier, one manufacturer and one or more retailers, in FMCG environment. Orders from retailers are supposed to iterate over cycles and parallel machines are available to process perishable jobs with given release dates, due dates and deadlines. To start process of he jobs, perishable raw material, supplied by an external supplier, is required. Jobs are subject to post-production shelf life limitation and must be delivered to retailers during the corresponding time window bounded by due dates and deadlines. Both early and tardy jobs are penalized by partial weighted earliness/tardiness functions and the...
Cross-layer rateless coding over wireless relay channel
, Article 2010 5th International Symposium on Telecommunications, IST 2010 ; 2010 , Pages 351-355 ; 9781424481835 (ISBN) ; Hossein Khalaj, B ; Sharif University of Technology
2010
Abstract
This paper focuses on cross-layer transmission based on rateless coding for relay channels. In the proposed method, rateless coding is used at packet level and a separate physical layer coding is used at the physical layer. As rateless codes are originally designed and optimized for erasure channels, using these codes at the physical layer can lead to significant performance degradation. The proposed scheme has the advantage of a cross-layer design which uses a rateless code at the packet level modeled by an erasure channel. Based on the analysis and simulation results provided in this paper, there is an exact tradeoff between physical layer code rate and rateless code depth, and the optimum...
Role of Affective Commitment in the Relationship between Ostracism and Turnover Intention
, M.Sc. Thesis Sharif University of Technology ; Banki, Sara (Supervisor)
Abstract
A lot of researchers have suggested that ostracism as a disruptive behavior, has been widespread among organizations and a lot of researches has been studied its consequences in recent years.This research studies ostracism’s consequences and proposes a theoretical model of organizational ostracism with affective commitment, intention to turnover and organizational dependability as one of affective commitment’s antecedents. This study has been done on 231 employees of three medium knowledge-based organizations to identify the effects of ostracism on employee’s turnover behavior. Results show that ostracism, due to its impact on the affective commitment of ostracized peoples, reduces this type...
Evaluation of Rateless Coding on Relay Networks
, M.Sc. Thesis Sharif University of Technology ; Hossein Khalaj, Babak (Supervisor)
Abstract
Fountain codes enable wireless networks to adapt their transmission rates to the state of the channels, without the need for channel state information (CSI) at the transmitters. According to the following properties of rateless codes, ever increasing parity generation, mutual information receiver, single bit feedback, and information combining receiver, they are good choice for relay networks. In this research, the design of rateless codes for wireless relay networks has been studied. Cross layer issues should be seriously considered when using rateless codes in the packet level. One cross-layer scheme has been developed in this thesis and analysis show that the performance of the proposed...
Cross-layer rateless coding over wireless relay networks
, Article IWCMC 2011 - 7th International Wireless Communications and Mobile Computing Conference, 4 July 2011 through 8 July 2011 ; July , 2011 , Pages 1545-1549 ; 9781424495399 (ISBN) ; Khalaj, B. H ; Pasandshanjani, E ; Sharif University of Technology
2011
Abstract
The focus of the paper is on cross-layer transmission based on rateless coding for relay networks. In the proposed method, rateless coding is used at the packet level and a separate physical layer coding is used at the physical layer. As rateless codes are originally designed and optimized for erasure channels, using these codes at the physical layer can lead to significant performance degradation. The proposed scheme has the advantage of a cross-layer design which uses a rateless code at the packet level modeled by an erasure channel. Based on the analysis and simulation results provided in this paper, the cross-layer scheme results in earlier successful decoding at the destination
A novel adaptive LMS-based algorithm considering relative velocity of source
, Article 2010 7th International Symposium on Communication Systems, Networks and Digital Signal Processing, CSNDSP 2010, 21 July 2010 through 23 July 2010, Newcastle upon Tyne ; 2010 , Pages 10-14 ; 9781861353696 (ISBN) ; Shirvani Moghaddam, M ; Kalami Rad, R ; Sharif University of Technology
2010
Abstract
In this paper a new least mean square (LMS) based adaptive weighting algorithm is proposed. It is appropriate for antenna array systems with moving targets and mobile applications. The essential goal of this algorithm is to reduce the complexity of weighting process and to decrease the time needed for adjusting the antenna radiation pattern. The main lobe of antenna will be adjusted in the direction of desired signal (main signal) and nulls pointed in the direction of undesired signals (interference signals). By predicting the relative velocity of source, the next location of the source will be estimated and the array weights will be determined using LMS algorithm before arriving to the new...
CMA-based adaptive antenna array digital beamforming with reduced complexity
, Article 2010 7th International Symposium on Communication Systems, Networks and Digital Signal Processing, CSNDSP 2010, 21 July 2010 through 23 July 2010, Newcastle upon Tyne ; 2010 , Pages 327-331 ; 9781861353696 (ISBN) ; Shirvani Moghaddam, M ; Kalami Rad, R ; Sharif University of Technology
2010
Abstract
Reducing the computational complexity as well as convergence time is the main task of adaptive antenna array processing. This article proposes an improved algorithm for estimating the weights of adaptive array elements based on Constant Modulus Algorithm (CMA). In this new type of algorithm, those weights that have higher effect on the radiation pattern will be estimated and antenna pattern will be adjusted by changing these weights. In this research, 3 new algorithms are proposed. By simulating these algorithms and comparing them with conventional full weight CMA, finally new algorithm that has a reduced complexity and an acceptable performance at different signal to noise ratios (SNRs) is...
Mitigating ferroresonance in coupling capacitor voltage transformers with ferroresonance suppressing circuits
, Article IEEE EUROCON 2009, EUROCON 2009, St. Petersburg, 18 May 2009 through 23 May 2009 ; 2009 , Pages 817-822 ; 9781424438617 (ISBN) ; Babazadeh, D ; Esmaeilnia Shirvani, R ; Purrezagholi, M ; Sharif University of Technology
2009
Abstract
In order to restrain ferroresonance in coupling capacitor voltage transformers (CCVT), two kinds of ferroresonance suppression circuits (FSCs) , are proposed in this paper: the resonant type, the fastsaturation reactor type which are connected to secondary side of CCVTs. Frequency domain analyses, for voltage ratio magnitude, are carried out for CCVTs to obtain preferable FSC. Furthermore, using surge suppressors such as metal oxide varistors (MOV) to improve the performance of the FSCs is investigated. Time domain simulations demonstrate that ferroresonance can be cleared in few cycles in presence of FSCs. The Electromagnetic Transients Program (EMTP) is used for modeling and fine-tuning...
DFT study of NH3(H2O) n=0,1,2,3 complex adsorption on the (8, 0) single-walled carbon nanotube
, Article Computational Materials Science ; Volume 48, Issue 3 , 2010 , Pages 655-657 ; 09270256 (ISSN) ; Beheshtian, J ; Parsafar, G ; Hadipour, N. L ; Sharif University of Technology
2010
Abstract
Theoretical study of NH3(H2O) n=0,1,2,3 adsorption on (8, 0) carbon nanotube was performed at the X3LYP/6-31G* level of density functional theory (DFT). The tube-NH3 interaction was discussed in the terms of binding energy (EB), coupling energy (EC), charge density, molecular orbitals, and dipole moments. The results reveal that addition of water molecules to tube-NH3 system increases the interaction between tube and ammonia molecule
Dendritic multi-walled carbon nanotube with thermoresponsive shells: A good carrier for anticancer drugs
, Article Journal of Industrial and Engineering Chemistry ; Volume 35 , 2016 , Pages 332-340 ; 1226086X (ISSN) ; Mazaheri Tehrani, Z ; Shirvani, T ; Doulabi, M ; Bumajdad, A ; Sharif University of Technology
Korean Society of Industrial Engineering Chemistry
2016
Abstract
In this research, multi-walled carbon nanotubes (MWCNTs) were modified by dendritic macromonomer. Herein, polyamidoamine with acrylamide end groups was incorporated on MWCNTs. Afterwards, poly(N-isopropylacrylamide), (PNIPAM), was grafted on polyamidoamine in a facile synthesis. Then, doxorubicin as anticancer drug was loaded on this nanocarrier. The drug release was studied at below and above the lower critical solution temperature of PNIPAM, (LCST 32 °C), 27 °C and 37 °C, respectively. At 37 °C (body temperature) the polymer shell dehydrated and the drug release increased. The profile of drug release was expressed by Higuchi's equation which indicated that the drug release mechanism was...
Experimental Study and Prediction of Vancomycin Partitioningin Surfactant-Salt Aqueous Two-Phase Systems
, M.Sc. Thesis Sharif University of Technology ; Vosughi, Manouchehr (Supervisor) ; Rashtchian, Davood (Supervisor) ; Pazuki, Gholamreza (Supervisor)
Abstract
In the past years, upstream processes have been receiving a considerable R&D investment and commercial attention. The downstream processes have, however, been overlooked causing a production bottleneck that is shifting the costs of production from up to downstream. The need to develop more efficient and cost-effective separation and purification processes is, thus, crucial in order to improve process efficiency and economics keeping the required high standards of quality for market approval. In this research, promising aqueous two-phase systems (ATPS) containing Tween 20 as a quite biocompatible non-ionic surfactant and different salts (K3Citrate and NaH2PO4) were prepared and their...
Identifying Active Followership Behaviors in Interaction with Managers with Autocratic Leadership Style in an Iranian Organization
, M.Sc. Thesis Sharif University of Technology ; Alavi, Babak (Supervisor) ; Banki, Sara (Supervisor)
Abstract
Purpose: The purpose of this thesis was to identify active followership behaviors of followers in interaction with autocratic leaders. An active follower thinks critically and takes initiatives.
Design: Given that Followership literature is still in its infancy, the research questions needed a qualitative approach, in this case grounded theory. In total, 19 top- & middle-level managers were interviewed as leaders and followers, accordingly, using semi-structured interviews.
Findings: 4 categories of active followership were found, each having 3-4 specific behaviors. These categories are: precautionary behaviors, facilitating behaviors, modificating behaviors, and consolidating...
Design: Given that Followership literature is still in its infancy, the research questions needed a qualitative approach, in this case grounded theory. In total, 19 top- & middle-level managers were interviewed as leaders and followers, accordingly, using semi-structured interviews.
Findings: 4 categories of active followership were found, each having 3-4 specific behaviors. These categories are: precautionary behaviors, facilitating behaviors, modificating behaviors, and consolidating...
An Investigation of the Mediating role of Organizational Cynicism on the Relations between the Politics Perception and Organizational Commitment
, M.Sc. Thesis Sharif University of Technology ; Alavi, Babak (Supervisor) ; Banki, Sara (Supervisor)
Abstract
There is no consensus definition of cynicism in literature. In this research different definitions of cynicism have been investigated and two concept of organizational cynicism and trait cynicism have been taken into consideration. Organizational cynicism is a negative attitude that is prevalent in employees. In literature some antecedents and consequences of organizational cynicism have been suggested. It seems organizational cynicism can be investigated in a more complex relations. The focus of this research is on the mediating role of organizational cynicism on the likely relations between politics perception and organizational commitment. That is to say organizational cynicism can...
The Influence of Authentic Leadership on the Relationship between Transformational Leadership, and Feedback-seeking Behaviors
, M.Sc. Thesis Sharif University of Technology ; Alavi, Babak (Supervisor) ; Banki, Sara (Supervisor)
Abstract
Feedback-seeking behavior is the effort of employees to get feedback from the environment and around people about their performance. One of the research questions in this field is about the factors that increase this behavior in the staff. Transformational leadership as a leadership style, stimulates, and motivates followers to achieving desirable operational results. In addition, an important consequence of this style could be increasing the followers' capabilities. Transformational leaders are trying to empower their followers to build and empower them, which can provide a strong incentive for employees to move and grow, which may encourage them to have a better performance. One of...
Applying Gamification in Corporate Entrepreneurship Culture, Specially Missionary Organizations; Through SafirFilm Case Study
, M.Sc. Thesis Sharif University of Technology ; Yavari, Elham (Supervisor) ; Banki, Sara ($item.subfieldsMap.e)
Abstract
Although existing literature on organizational culture and its change process contains meaningful and rich theories but our studies show that there is no perfect and detailed framework on linking organizational culture change and corporate entrepreneurship culture. In addition to that, Gamification –defined as taking the game design elements into non-game contexts– is a fruitful and academically rich research area. Fortunately an idea proposed recently to explain a method for enhancements in organizational culture in general, and in corporate entrepreneurship culture in particularby Yavari and Jafarian based on using game mechanisms. In their paper "A Gamification-Based Method for Corporate...
Synthesis of Tin and Ti2n Nanostructured Coatings on Ti alloys Using Magnetron Sputtering System And Comparison of Their Biocompatibility Properties
, M.Sc. Thesis Sharif University of Technology ; Nemati, Ali (Supervisor) ; Khamse, Sara (Supervisor)
Abstract
Considering the importance of biocompatibility of implantable prothesis’, metallic alloys have weaker corrosion resistance than ceramics. In order to extend usage of nanomaterials to improve the bio-properties of materials, Nano-structured ceramic coatings are being suggested to improve corrosion resistance and biocompatibility of prosthesis. Meanwhile, very good properties of TiN, such as corrosion resistance and mechanical properties as a thin film coating are undeniable. In this study, TiN and Ti2N thin film were deposited on Ti-based substrate, using PVD and Magnetron sputtering at different argon to nitrogen ratio. The crystal structure of the films was examined using Grazing XRD...
Voltage and frequency consensusability of autonomous microgrids over fading channels
, Article IEEE Transactions on Energy Conversion ; Volume 36, Issue 1 , 2021 , Pages 149-158 ; 08858969 (ISSN) ; Khorsandi, A ; Baghaee, H. R ; Sadati, N ; Shirvani Moghaddam, S ; Guerrero, J. M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
In this article, a novel cooperative secondary voltage/frequency control considering time-varying delays and noises in fading channels is presented for an autonomous alternating current (AC) voltage sourced-based converter (VSC)-based microgrid (MG), including inverter-interfaced distributed generations (DGs). Fading phenomenon makes complex random fluctuations on the voltage and frequency of every DG received from its neighbor DGs. In multi-agent cooperative systems, in addition to the total additive noise and time-variant delay, a multiplicative complex random variable is considered to model the main received signal and its replicas due to multipath propagation. The proposed...
The Instructional Effect of Dynamic-assessment, Non-dynamic Traditional Assesment, and Non-assessment Courses on Iranian EFL Learners' Interlanguage Pragmatic Production
, M.Sc. Thesis Sharif University of Technology ; Tajeddin, Zia (Supervisor) ; Alemi, Minoo (Supervisor)
Abstract
There are several methods proposed for the instruction and assessment of interlanguage pragmatic competence of foreign language learners. Dynamic assessment as one of the recent methods arising from Vygotsky’s sociocultural theory of mind incorporates assessment and instruction by engaging learners in a process of interaction with the mediator while the learners are trying to perform a challenging task. The present study aimed to explore the advantage of Dynamic Assessment as an instructional instrument over the Non-dynamic (traditional) Assessment and Non-assessment approaches and their effects on the Iranian intermediate level students. The target speech acts of apology, complaint, and...