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    A screw dislocation near a damaged arbitrary inhomogeneity–matrix interface

    , Article International Journal of Damage Mechanics ; Volume 29, Issue 2 , 2020 , Pages 272-296 Kamali, M. T ; Shodja, H. M ; Masoudvaziri, N ; Sharif University of Technology
    SAGE Publications Ltd  2020
    Abstract
    In the literature, the analytical solutions concerned with the interaction between screw dislocation and surfaces/interfaces have been mainly limited to simple geometries and perfect interfaces. The focus of the current work is to provide an approach based on a rigorous semi-analytical theory suitable for treatment of such surfaces/interfaces that concurrently have complex geometry and imperfect bonding. The proposed approach captures the singularity of the elastic fields exactly. A vast variety of the pertinent interaction problems such as dislocation near a multi-inhomogeneity with arbitrary geometry bonded imperfectly to a matrix, dislocation near the free boundaries of a finite elastic... 

    Comprehensive hydrothermal analysis of an inclined mini-channel with fin array: by dual/multi-relaxation-time LBM and experimental process on SiO2-glycol rheological/thermal characteristics

    , Article International Journal of Numerical Methods for Heat and Fluid Flow ; Volume 31, Issue 7 , 2021 , Pages 2405-2429 ; 09615539 (ISSN) Kamali, D ; Hejri, S ; Akbar, N ; Hasani Malekshah, E ; Sharif University of Technology
    Emerald Group Holdings Ltd  2021
    Abstract
    Purpose: The purpose of this study is to present a comprehensive hydrothermal analysis on an inclined mini-channel using numerical and experimental techniques. The fin array acts as heat source within the channel, and a wavy wall located at the top of the channel is heat sink. The side walls are insulated with curved profiles. Also, the channel is inclined with four known inclination angles. To solve the governing equations, the dual-multi-relaxation-time lattice Boltzmann method with D2Q9 and D2Q5 lattice models for flow and temperature fields is used, respectively. Also, the channel is filled with SiO2-glycol nanofluid. Design/methodology/approach: Identifying the behavior of a thermal... 

    SPONGE: a scalable pivot-based on/off gating engine for reducing static power in NoC routers

    , Article Proceedings of the International Symposium on Low Power Electronics and Design23 July 2018 ; 23-25 July , 2018 ; 15334678 (ISSN) ; 9781450357043 (ISBN) Farrokhbakht, H ; Mardani Kamali, H ; Jerger, N. E ; Hessabi, S ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2018
    Abstract
    Due to high aggregate idle time of Networks-on-Chip (NoCs) routers in practical applications, power-gating techniques have been proposed to combat the ever-increasing ratio of static power. Nevertheless, the sporadic packet arrivals compromise the effectiveness of power-gating by incurring significant latency and energy overhead. In this paper, we propose a Scalable Pivot-based On/Off Gating Engine (SPONGE) which efficiently manages power-gating decisions and routing mechanism by adaptively selecting a small set of powered-on columns of routers and keeping the others in power-gated state. To this end, a router architecture augmented with a novel routing algorithm is proposed in which a... 

    Matching with moral hazard: Assigning attorneys to poor defendants

    , Article American Economic Journal: Microeconomics ; Volume 10, Issue 3 , 2018 , Pages 1-33 ; 19457669 (ISSN) Kamali Shahdadi, B ; Sharif University of Technology
    American Economic Association  2018
    Abstract
    We model the problem of assigning counsel to poor defendants as a matching problem. A novel aspect of this matching problem is the moral hazard component on the part of counsel. Within the model, we show that holding the total expenditure for counsel fixed and changing the matching procedure to accommodate defendants' and attorneys' preferences, i.e., switch from random matching to stable matching, defendants become worse offbecause a stable matching exacerbates the moral hazard problem on the part of counsel. In addition, we show that under suitable conditions random matching is the efficient way to allocate defendants to counsel. © 2018 American Economic Association  

    Fabrication and evaluation of a bilayer hydrogel-electrospinning scaffold prepared by the freeze-gelation method

    , Article Journal of Biomechanics ; Volume 98 , 2020 Kamali, A ; Shamloo, A ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    This study presents a bilayer structure as a skin scaffold comprised of an electrospun sheet layer made of polycaprolactone and polyvinil alcohol and a porous hydrogel layer made of chitosan and gelatin. The hydrogel layer was fabricated by employing the freeze-gelation technique. The bilayer structure was achieved by pouring the hydrogel solution on the electrospun sheet at the bottom of a mold followed by the freeze-gelation technique to obtain a porous structure in the hydrogel. The hydrogel and hydrogel-electrospun samples were characterized by scanning electron microscopy, swelling, tensile strength, in vitro and in vivo analyses. From a mechanical strength standpoint, the combination... 

    Static and Dynamic Analysis of Nano Beams based on Second Strain Gradient Theory

    , M.Sc. Thesis Sharif University of Technology Kamali, Farhad (Author) ; Eskandari, Morteza (Supervisor)
    Abstract
    In this thesis, static and dynamic analysis of nano beams based on second strain gradient theory is presented. Due to their small sizes, nano electro mechanical devices (NEMS) hold tremendous promise for novel, versatile and very sensitive devices for different applications ranging from actuators, transducers and also mass, force, light and frequency detectors. Therefore accurate modeling and analysis of such devices has an important role in their design and performance improvement. Neglecting the size effect, traditional theory of elasticity can not be suitable to predict mechanical behavior of these systems and so, it should be used non-classical theories which include size dependency... 

    Multi-Label Text Classification

    , M.Sc. Thesis Sharif University of Technology Kamali, Sajjad (Author) ; Beigy, Hamid (Supervisor)
    Abstract
    Nowadays, with the increasing size of data,it’s impossible to collect data and fast classification by human, and needs for an automated classification and data analysis, is more interested. Data classification is a process of giving the training data along with their class labels to the learning agent, which learns the relation between the instances and the labels. Then make a prediction to the label of the training data.In this thesis we will observe the classification of the multi-label data. Multi-label data have more than one label. In other words, each instance appears with a vector of labels.In this thesis, a method based on nearest neighbor is proposed to classify the multi-label... 

    Prediction of Air Pollutants’ Hourly Concentration in Tehran Using Artificial Neural Network and Specteral Decomposition of Time Series Data

    , M.Sc. Thesis Sharif University of Technology Kamali, Nima (Author) ; Arhami, Mohammad (Supervisor)
    Abstract
    Recent progress in developing Artificial Neural Network (ANN) meta-models has paved the way for reliable use of these models in the prediction of air pollutant concentrations in urban atmosphere. However, improvement of prediction performance, proper selection of input parameters and model architecture remain key challenges to their practical use. This study’s main objectives are: selecting proper input parameters for ANN meta-models, optimizing the ANN models to achieve the most accurate hourly prediction for a case study (City of Tehran), coupling the ANN method with filtered input data and evaluating its privilege. In the current study the ANNs were constructed to predict criteria... 

    Are Quantum Mechanics and Special Relativity in Peaceful Coexistence?

    , M.Sc. Thesis Sharif University of Technology Kamali, Saeed (Author) ; Golshani, Mehdi (Supervisor)
    Abstract
    Quantum mechanics is very succesful in the description and prediction of the microphysical world. So nowadays very few doubt its authenticity. Nevertheless, there are some conceptual issues that are still under debate, such as action at a distance. It took a while after the introduction of the EPR paradox in 1935 until John Stewart Bell derived an inequality, using local hidden variables. This inequality was in contrast with predictions of quantum mechanics. Experiments also contradicted this inequality. This implies that there is action at distance which, in turn suggests, the violation of the special relativity. In this thesis, we consider this issue and shall see that on the one hand we... 

    Credit Scoring for Maskan Bank Customers

    , M.Sc. Thesis Sharif University of Technology Kamali, Behrang (Author) ; Zamani, Shiva (Supervisor)
    Abstract
    Credit scoring is a mechanism used to quantify the risk factors relevant for an obligor’s ability and willingness to pay. Credit scoring has become the norm in modern banking, due to the large number of applications received on a daily basis and the increased regulatory requirements for banks. The meaning of credit scoring is to assign scores to the characteristics of debt and borrowers, historical default, and other loss experienced as an indication of the risk level of the borrower. The aim of the credit score model is to build a single aggregate risk indicator for a set of risk factors.
    In this study, current method in which Maskan bank will give a loan is explained. We developed a... 

    Dynamic analysis of an a-shaped piezo-actuated walking microrobot

    , Article ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE), 12 November 2010 through 18 November 2010, Vancouver, BC ; Volume 10 , 2010 , Pages 161-170 ; 9780791844472 (ISBN) Kamali Eigoli, A ; Vossoughi, G ; Sharif University of Technology
    2010
    Abstract
    In this paper, a novel, A-shaped microrobot with nanometric resolution for precision positioning applications is addressed. The locomotion concept of the mechanism is founded on the "friction drive principle". To achieve the translational motion, a stack piezoelectric actuates the microrobot near its natural frequency. The dynamic modeling of the mechanism is based on the assumptions of linear behavior of piezo stack actuator and Coulomb friction model at contact points. The suitability of three simple, friction-based locomotion modes for implementation on the proposed device is presented. Influences of different friction coefficients on the behavior of the microrobot, with respect to... 

    A fault tolerant parallelism approach for implementing High-throughput pipelined advanced encryption standard

    , Article Journal of Circuits, Systems and Computers ; Volume 25, Issue 9 , 2016 ; 02181266 (ISSN) Mardani Kamali, H ; Hessabi, S ; Sharif University of Technology
    World Scientific Publishing Co. Pte Ltd  2016
    Abstract
    Advanced Encryption Standard (AES) is the most popular symmetric encryption method, which encrypts streams of data by using symmetric keys. The current preferable AES architectures employ effective methods to achieve two important goals: protection against power analysis attacks and high-throughput. Based on a different architectural point of view, we implement a particular parallel architecture for the latter goal, which is capable of implementing a more efficient pipelining in field-programmable gate array (FPGA). In this regard, all intermediate registers which have a role for unrolling the main loop will be removed. Also, instead of unrolling the main loop of AES algorithm, we implement... 

    AdapNoC: A fast and flexible FPGA-based NoC simulator

    , Article 26th International Conference on Field-Programmable Logic and Applications, FPL 2016, 29 August 2016 through 2 September 2016 ; 2016 ; 9782839918442 (ISBN) Mardani Kamali, H ; Hessabi, S ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2016
    Abstract
    Network on Chip (NoC) is the most common interconnection platform for multiprocessor systems-on-chips (MPSoCs). In order to explore the design space of this platform, we need a high-speed, cycle-accurate, and flexible simulation tool. In this paper, we present AdapNoC, a configurable cycle-accurate FPGA-based NoC simulator, which can be configured via software. A wide range of parameters are configurable in FPGA side of the proposed simulator, and the software side is implemented on an embedded soft-core processor. We transfer some parts of simulator, such as Traffic Generators (TGs) and Traffic Receptors (TRs), to software side without any degradation in simulation speed. Moreover, we... 

    E-Business B2B Developing a System

    , M.Sc. Thesis Sharif University of Technology Kamali, Shiva (Author) ; Modarres Yazdi, Mohammad (Supervisor)
    Abstract
    The purpose of this thesis is to develop an e-Business B2B system for a company. We review e-Business concepts, its requirements as well as the obstacles to implement it. Then, the various kinds of e-Business, their advantages and disadvantages are discussed. We study the outcome of e-Business system implemented in two Iranian companies. Then, we design an information system for one company. Indeed, this system presents the process of purchasing and sale representing the transactions between the company and its sale representatives. This information system is designed within Microsoft Access environment. This system can make this company capable of entering international markets by... 

    Design and Analysis of Vibration-Based, Friction-Drive Micro-Mechanisms for Planar, Nano-Scale Locomotion

    , M.Sc. Thesis Sharif University of Technology Kamali Eigoli, Ali (Author) ; Vossoughi, Gholamreza (Supervisor)
    Abstract
    Design and modeling of a micromechanism for generating planar, nano-scaled locomotion is the subject of this thesis. First, we introduced the concepts and fundamental definitions used throughout the thesis. Then, based on the classification of the locomotion principles employed in microrobots, the related literature about design and fabrication of different microrobots is investigated. Inertial slip generation and contact force variation, as the preferred group, is utilized for further analysis. Since friction force is the main propelling source in the microrobot’s locomotion principle, different models proposed for this phenomenon are investigated and the Coulomb friction model is selected... 

    Change Point Detection and Analysis in Poisson Processes

    , M.Sc. Thesis Sharif University of Technology Kamali, Mahsa (Author) ; Akhavan Niaki, Taghi (Supervisor)
    Abstract
    Control charts are one of the most important tools in statistical process control to detect assignable causes. The goal of a control chart is to detect an out-of-control state quickly so that process engineers can initiate their search for the special cause sooner. Once the special cause has been identified, the appropriate action can then be taken to improve the process.A new method to estimate the change point of Poisson rate parameter when the step change occurs is proposed in this thesis. That is, the rate parameter is assumed to suddenly shift from its in-control value to an out-of control value at a single unknown point in the process.To do this, a belief that the process is in-control... 

    A periodic solution for friction drive microrobots based on the iteration perturbation method

    , Article Scientia Iranica ; Volume 18, Issue 3 B , 2011 , Pages 368-374 ; 10263098 (ISSN) Kamali Eigoli, A ; Vossoughi, G. R ; Sharif University of Technology
    2011
    Abstract
    The friction drive principle, which is based on the superposition of two synchronized perpendicular vibrations at the interface of the robot and the work floor, plays a fundamental role in the locomotion of miniaturized robots. In this paper, the iteration perturbation method proposed by He is used to generate a periodic solution for this type of friction drive microrobot. The equation of motion for the system reveals a parametrically excited oscillator with discontinuity, the elastic force term for which is proportional to a signum function. The obtained solutions are in excellent agreement with those achieved from numerical integration and experiments reported in the literature. Results... 

    Nonlinear vibration of beams under nonideal boundary conditions

    , Article Acta Mechanica ; Volume 218, Issue 3-4 , 2011 , Pages 259-267 ; 00015970 (ISSN) Kamali Eigoli, A ; Ahmadian, M. T ; Sharif University of Technology
    2011
    Abstract
    In this paper, we investigate the influence of nonideal boundary conditions on the nonlinear vibration of damped Euler-Bernoulli beams subjected to harmonic loads. These nonidealities allow for small deflections and/or moments at the supports of the beam. Using the iteration perturbation method, analytical expressions for the case of simply supported beams with immovable end conditions are provided. The results reveal that the first order of approximation obtained by the proposed method is more accurate than the perturbation solutions. Moreover, compared with the previous studies, some interesting phenomenon is predicted. We have shown that in some special combinations of the nonidealities... 

    Freeze-gelled alginate/gelatin scaffolds for wound healing applications: An in vitro, in vivo study

    , Article Materials Science and Engineering C ; Volume 113 , 2020 Afjoul, H ; Shamloo, A ; Kamali, A ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    In this study, fabrication of a three-dimensional porous scaffold was performed using freeze gelation method. Recently, fabrication of scaffolds using polymer blends has become common for many tissue engineering applications due to their unique tunable properties. In this work, we fabricated alginate-gelatin porous hydrogels for wound healing application using a new method based on some modifications to the freeze-gelation method. Alginate and gelatin were mixed in three different ratios and the resulting solutions underwent freeze gelation to obtain 3D porous matrices. We analyzed the samples using different characterization tests. The scanning electron microscopy (SEM) results indicated... 

    Interaction of a screw dislocation and an embedded nonuniformly coated circular fiber with imperfect interfaces

    , Article International Journal of Solids and Structures ; Volume 182-183 , 2020 , Pages 295-306 Kamali, M. T ; Shodja, H. M ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    The eccentricity between the circular fiber and its coating as well as the imperfection at the fiber-coating-matrix interfaces associated with certain composites can have a remarkable effect on the movement of a dislocation. For an in-depth understanding of such phenomena, the present work provides an exact analytical solution for the interaction between an eccentrically coated circular inhomogeneity embedded in an infinite elastic medium with imperfect interfaces and a screw dislocation. The dislocation may be located inside one of the regions: the core inhomogeneity, coating, or the matrix. The corresponding boundary value problem is solved by using conformal mapping and complex potential...