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    A survey of dynamic software updating

    , Article Journal of software: Evolution and Process ; Volume 25, Issue 5 , 2013 , Pages 535-568 ; 20477481 (ISSN) Seifzadeh, H ; Abolhassani, H ; Moshkenani, M. S ; Sharif University of Technology
    2013
    Abstract
    Application update at run-time remains a challenging issue in software engineering. There are many techniques with different evaluation metrics, resulting in different behaviours in the application being updated. In this paper, we provide an extensive review of research work on dynamic software updating. A framework for the evaluation of dynamic updating features is developed, and the articles are categorized and discussed based on the provided framework. Areas of online software maintenance requiring further research are also identified and highlighted. This information is deemed to not only assist practitioners in selecting appropriate dynamic updating techniques for their systems, but... 

    Finding feasible timetables with particle swarm optimization

    , Article Innovations'07: 4th International Conference on Innovations in Information Technology, IIT, Dubai, 18 November 2007 through 20 November 2007 ; 2007 , Pages 387-391 ; 9781424418411 (ISBN) Qarouni Fard, D ; Najafi Ardabifi, A ; Moeinzadeh, M. H ; Sharifian R, S ; Asgarian, E ; Mohammadzadeh, J ; Sharif University of Technology
    IEEE Computer Society  2007
    Abstract
    A Timetabling problem is usually defined as assigning a set of events to a number of rooms and timeslots such that they satisfy a number of constraints. Particle swarm optimization (PSO) is a stochastic, population-based computer problem-solving algorithm; it is a kind of swarm intelligence that is based on social-psychological principles and provides insights into social behavior, as well as contributing to engineering applications. This paper applies the Particle Swarm Optimization algorithm to the classic Timetabling problem. This is inspired by similar attempts belonging to the evolutionary paradigm in which the metaheuristic involved is tweaked to suit the grouping nature of problems... 

    Activities performed by programmers while using framework examples as a guide

    , Article Proceedings of the ACM Symposium on Applied Computing ; 2014 , p. 1146-1151 Boghrati, R ; Heydarnoori, A ; Kazemitabaar, M ; Sharif University of Technology
    Abstract
    It is now a common approach pursued by programmers to develop new software systems using Object-Oriented Application Frameworks such as Spring, Struts and, Eclipse. This improves the quality and the maintainability of the code. Furthermore, it reduces development cost and time. However, the main problem is that these frameworks usually have a complicated Application Programming Interface (API), and typically suffer from the lack of enough documentation and appropriate user manuals. To solve these problems, programmers often refer to existing sample applications of those frameworks to learn how to implement the desired functionality in their own code. This is called the Monkey See, Monkey Do... 

    Effective behavior of porous elastomers containing aligned spheroidal voids

    , Article Acta Mechanica ; Volume 224, Issue 9 , September , 2013 , Pages 1901-1915 ; 00015970 (ISSN) Avazmohammadi, R ; Naghdabadi, R ; Sharif University of Technology
    2013
    Abstract
    The theoretical need to recognize the link between the basic microstructure of nonlinear porous materials and their macroscopic mechanical behavior is continuously rising owing to the existing engineering applications. In this regard, a semi-analytical homogenization model is proposed to establish an overall, continuum-level constitutive law for nonlinear elastic materials containing prolate/oblate spheroidal voids undergoing finite axisymmetric deformations. The microgeometry of the porous materials is taken to be voided spheroid assemblage consisting of confocally voided spheroids of all sizes having the same orientation. Following a kinematically admissible deformation field for a... 

    Stress-jump and Continuity Interface Conditions for a Cylinder Embedded in a Porous Medium

    , Article Transport in Porous Media ; Volume 107, Issue 1 , 2015 , Pages 171-186 ; 01693913 (ISSN) Rashidi, S ; Nouri Borujerdi, A ; Valipour, M. S ; Ellahi, R ; Pop, I ; Sharif University of Technology
    Kluwer Academic Publishers  2015
    Abstract
    The selection of interface boundary conditions between porous-medium and clear-fluid regions is very important for the wide range of engineering applications. In this paper, the difference between two common types of fluid flow interfacial conditions between clear fluid and porous medium is analyzed in detail. These two types of fluid flow interfacial condition are stress-jump and stress-continuity conditions. The effects of porosity on these types of interface condition are studied. The results are presented for different Reynolds numbers in the range 1–40, porosity equal to 0.4 and 0.8 and Darcy number Da=5×10-4. In this study, the Darcy–Brinkmann–Forchheimer model is used to model the... 

    A novel correlation approach for viscosity prediction of water based nanofluids of Al2O3, TiO2, SiO2 and CuO

    , Article Journal of the Taiwan Institute of Chemical Engineers ; Volume 58 , 2016 , Pages 19-27 ; 18761070 (ISSN) KalantariMeybodi, M ; Daryasafar, A ; MoradiKoochi, M ; Moghadasi, J ; BabaeiMeybodi, R ; KhorramGhahfarokhi, A ; Sharif University of Technology
    Taiwan Institute of Chemical Engineers  2016
    Abstract
    Nanofluids viscosity is one of the most important thermophysical properties in nanofluids usage especially in chemical and petroleum engineering applications. So it is highly desirable to predict the viscosity of nanofluids accurately. Experimental measurements are impossible in most situations and present models are not comprehensive and efficient especially for high temperature, high volume concentration and high viscosity values. In this study, a new correlation has been developed based on the comprehensive database of water based Al2O3, TiO2, SiO2 and CuO nanofluids viscosity data found in literature. The proposed correlation uses temperature, nanoparticle size, nanoparticle volumetric... 

    Applying portfolio theory-based modified ABC to electricity generation mix

    , Article International Journal of Electrical Power and Energy Systems ; Volume 80 , 2016 , Pages 356-362 ; 01420615 (ISSN) Adabi, F ; Mozafari, B ; Ranjbar, A. M ; Soleymani, S ; Sharif University of Technology
    Elsevier Ltd  2016
    Abstract
    Portfolio theory has found its model in numerous engineering applications for optimizing the electrical generation mix of an electricity area. However, to have better performance of this theory, this paper presents a new heuristic method as known modified artificial bee colony (MABC) to portfolio optimization problem. Moreover, we consider both dis-patchable and non-dis-patchable constrains variables and energy sources. Note that the proposed MABC method uses a Chaotic Local Search (CLS) to enhance the self searching ability of the original ABC algorithm. Resulting, in this paper a portfolio theory-based MABC model that explicitly distinguishes between electricity generation (energy),... 

    Transient thermal behavior of radial fins of rectangular, triangular and hyperbolic profiles with temperature-dependent properties using DTM-FDM

    , Article Journal of Central South University ; Volume 24, Issue 3 , 2017 , Pages 675-682 ; 20952899 (ISSN) Mosayebidorcheh, S ; Rahimi Gorji, M ; Ganji, D. D ; Moayebidorcheh, T ; Pourmehran, O ; Biglarian, M ; Sharif University of Technology
    Central South University of Technology  2017
    Abstract
    This work focuses on transient thermal behavior of radial fins of rectangular, triangular and hyperbolic profiles with temperature-dependent properties. A hybrid numerical algorithm which combines differential transformation (DTM) and finite difference (FDM) methods is utilized to theoretically study the present problem. DTM and FDM are applied to the time and space domains of the problem, respectively. The accuracy of this method solution is checked against the numerical solution. Then, the effects of some applicable parameters were studied comparatively. Since a broad range of governing parameters are investigated, the results could be useful in a number of industrial and engineering... 

    A finite element model for tapered laminated beams incorporated with magnetorheological fluid using a layerwise model under random excitations

    , Article Mechanics of Advanced Materials and Structures ; Apr , 2018 , Pages 1-8 ; 15376494 (ISSN) Momeni, S ; Zabihollah, A ; Behzad, M ; Sharif University of Technology
    Taylor and Francis Inc  2018
    Abstract
    Laminated composite beams with variable thickness are being widely used in many engineering applications. To enhance the dynamic behavior of structures subject to random loading, tapered laminated beams incorporated with magnetorheological (MR) fluids (MR-tapered beam) are proposed. A finite element model has been developed for random vibration analysis of MR-tapered beam based on layerwise displacement theory. The effects of thickness ratios of tapered beam, magnetic fields, statistical properties, correlation and autocorrelation on dynamic behaviors of structures have been investigated. The proposed structural element significantly enhances the dynamic response of MR-tapered beam under... 

    On modeling of wave propagation in a thermally affected GNP-reinforced imperfect nanocomposite shell

    , Article Engineering with Computers ; Volume 35, Issue 4 , 2019 , Pages 1375-1389 ; 01770667 (ISSN) Ebrahimi, F ; Habibi, M ; Safarpour, H ; Sharif University of Technology
    Springer London  2019
    Abstract
    Due to rapid development of process manufacturing, composite materials with porosity have attracted commercial attention in promoting engineering applications. For this regard, in this research wave propagation-thermal characteristics of a size-dependent graphene nanoplatelet-reinforced composite (GNPRC) porous cylindrical nanoshell in thermal environment are investigated. The effects of small scale are analyzed based on nonlocal strain gradient theory (NSGT). The governing equations of the laminated composite cylindrical nanoshell in thermal environment have been evolved using Hamilton’s principle and solved with the assistance of the analytical method. For the first time, wave... 

    Bioresorbable composite polymeric materials for tissue engineering applications

    , Article International Journal of Polymeric Materials and Polymeric Biomaterials ; 2020 Hajebi, S ; Mohammadi Nasr, S ; Rabiee, N ; Bagherzadeh, M ; Ahmadi, S ; Rabiee, M ; Tahriri, M ; Tayebi, L ; Hamblin, M. R ; Sharif University of Technology
    Taylor and Francis Inc  2020
    Abstract
    This review covers the development of bioresorbable polymeric composites for applications in tissue engineering. Various commercially available bioresobable polymers are described, with emphasis on recent bioresorbable composites based on natural and synthetic polymers. Bioresorbable polymers contain hydrolyzable bonds, which are subjected to chemical degradation via either reactive hydrolysis or enzyme-catalyzed active hydrolysis. For synthetic polymers, chemical hydrolysis is the most important mode of degradation. The degradation rate can be controlled by varying the molecular weight and crystallinity. Examples of bioresorbable polymers are: polyurethane, poly(D,L)lactide,... 

    A finite element model for tapered laminated beams incorporated with magnetorheological fluid using a layerwise model under random excitations

    , Article Mechanics of Advanced Materials and Structures ; Volume 27, Issue 1 , 2020 , Pages 12-19 Momeni, S ; Zabihollah, A ; Behzad, M ; Sharif University of Technology
    Taylor and Francis Inc  2020
    Abstract
    Laminated composite beams with variable thickness are being widely used in many engineering applications. To enhance the dynamic behavior of structures subject to random loading, tapered laminated beams incorporated with magnetorheological (MR) fluids (MR-tapered beam) are proposed. A finite element model has been developed for random vibration analysis of MR-tapered beam based on layerwise displacement theory. The effects of thickness ratios of tapered beam, magnetic fields, statistical properties, correlation and autocorrelation on dynamic behaviors of structures have been investigated. The proposed structural element significantly enhances the dynamic response of MR-tapered beam under... 

    Bioresorbable composite polymeric materials for tissue engineering applications

    , Article International Journal of Polymeric Materials and Polymeric Biomaterials ; Volume 70, Issue 13 , 2021 , Pages 926-940 ; 00914037 (ISSN) Hajebi, S ; Mohammadi Nasr, S ; Rabiee, N ; Bagherzadeh, M ; Ahmadi, S ; Rabiee, M ; Tahriri, M ; Tayebi, L ; Hamblin, M. R ; Sharif University of Technology
    Bellwether Publishing, Ltd  2021
    Abstract
    This review covers the development of bioresorbable polymeric composites for applications in tissue engineering. Various commercially available bioresobable polymers are described, with emphasis on recent bioresorbable composites based on natural and synthetic polymers. Bioresorbable polymers contain hydrolyzable bonds, which are subjected to chemical degradation via either reactive hydrolysis or enzyme-catalyzed active hydrolysis. For synthetic polymers, chemical hydrolysis is the most important mode of degradation. The degradation rate can be controlled by varying the molecular weight and crystallinity. Examples of bioresorbable polymers are: polyurethane, poly(D,L)lactide,... 

    Optimization of air plasma sprayed thermal barrier coating parameters in diesel engine applications

    , Article Journal of Materials Engineering and Performance ; Volume 22, Issue 11 , 2013 , Pages 3530-3538 ; 10599495 (ISSN) Azadi, M ; Farrahi, G. H ; Moridi, A ; Sharif University of Technology
    2013
    Abstract
    In the present paper, an optimization of thermal barrier coating parameters is performed for diesel engine applications. The substrate is A356.0-T7, a cast aluminum alloy which has a vast application in diesel engines, and the alloy is coated by plasma sprayed ZrO2-8 wt.% Y2O3. Parameters including the feed rate of coating powders, the nozzle distance to specimen surfaces, and the coating thickness are optimized by thermal shock fatigue tests and bending tests. Optimum values of the feed rate and the nozzle distance are 30 g/min and 80 mm, respectively, when the objective is considered as maximizing the bending strength. Thermal shock tests demonstrate that lower thickness of coating layers... 

    Preparation of PVA nanocomposites using salep-reduced graphene oxide with enhanced mechanical and biological properties

    , Article RSC Advances ; Volume 5, Issue 112 , 2015 , Pages 92428-92437 ; 20462069 (ISSN) Pourjavadi, A ; Pourbadiei, B ; Doroudian, M ; Azari, S ; Sharif University of Technology
    Royal Society of Chemistry  2015
    Abstract
    Salep, known as a biodegradable polysaccharide, is hydrolyzed and used as both a reducing agent and stabilizer for graphene oxide (GO). The functionalized reduced graphene oxide (f-rGO) is homogenously dispersed in an aqueous solution of poly(vinyl alcohol) (PVA). PVA based hydrogel and film nanocomposites are prepared and proposed as new biomaterials for tissue engineering applications. The mechanical properties of the film nanocomposites are investigated with varying content of f-rGO, glycerol and citric acid as a reinforcing agent, a plasticizer agent and a cross linking agent respectively. For the first time, chemically cross linked PVA hydrogels are synthesized using... 

    Buckling analysis of tapered composite beams using a higher order finite element formulation

    , Article Journal of Reinforced Plastics and Composites ; Volume 29, Issue 17 , 2010 , Pages 2663-2683 ; 07316844 (ISSN) Zabihollah, A ; Ganesan, R ; Sharif University of Technology
    2010
    Abstract
    Tapered composite beams are increasingly being used in various engineering applications such as helicopter yoke, robot arms, and turbine blades. In the present work, the buckling analysis of laminated tapered composite beams is conducted using a higher order finite element formulation. In tapered laminates, the material and geometric discontinuities at ply drop-off locations lead to significant discontinuities in stress distributions. Higher order formulation ensures the continuity of the stress distribution through the thickness of a laminate as well as across the element interfaces, which is very important for the analysis of tapered laminates. In addition, higher order finite element... 

    Effect of different bases and neutralization steps on porosity and properties of collagen-based hydrogels

    , Article Polymer International ; Volume 59, Issue 1 , 2010 , Pages 36-42 ; 09598103 (ISSN) Pourjavadi, A ; Kurdtabar, M ; Sharif University of Technology
    Abstract
    The aim of the work reported was to investigate the effect of bases and neutralization steps on hydrogel microstructures. A series of porous hydrogels with various pore sizes were prepared by neutralizing a conventional hydrogel after gel formation. Scanning electron microscopy was used to characterize the microstructure of the porous hydrogels. The morphology of the samples showed the pores were induced into the hydrogels by water evaporation and gas release resulting from the neutralization process. Experimental results indicated that the hydrogels had an absorbency of 200-220 and 48-50 g g-1 for distilled water and sodium chloride solutions, respectively. A simple method was used to... 

    The role of microstructural features on the electrical resistivity and mechanical properties of powder metallurgy Al-SiC-Al2O3 nanocomposites

    , Article Materials and Design ; Volume 130 , 2017 , Pages 26-36 ; 02641275 (ISSN) Khodabakhshi, F ; Simchi, A ; Sharif University of Technology
    Abstract
    There are many engineering applications in which composite materials are required to satisfy two or more criteria regarding physical and mechanical properties. In this article, Al-matrix nanocomposites reinforced with different volume fractions of SiC nanoparticles (~ 50 nm; up to 6%) were processed by powder metallurgy (P/M) routes through mechanical milling and hot consolidation techniques. Microstructural studies showed that nano-metric Al2O3 particles with a size of ~ 20 nm and volume fraction of ~ 2% were formed and distributed in the metal matrix, owing to the surface oxides breaking. Microstructural analysis also revealed that the size of cellular structure and the density of... 

    Investigation of the effect of cavitation passive control on the dynamics of unsteady cloud cavitation

    , Article Applied Mathematical Modelling ; Volume 64 , 2018 , Pages 333-356 ; 0307904X (ISSN) Kadivar, E ; Moctar, O. E ; Javadi, K ; Sharif University of Technology
    Abstract
    We present an efficient method to control the evolution of unsteady cloud cavitation around the CAV2003 benchmark hydrofoil using passive cavitation controllers so called cavitation-bubble generators (CGs). Cavitation control may be used in many engineering applications, particularly in the marine and turbo machinery field. We first simulated the unsteady cavitating flow around the hydrofoil without CGs using a Partially-averaged Navier–Stokes (PANS) method, and validated the acquired results against experimental data. We coupled the turbulence model with a mass transfer model and successfully implemented it in the open source toolbox OpenFOAM. Next, we studied the effect of different CGs on... 

    A discrete water cycle algorithm for solving the symmetric and asymmetric traveling salesman problem

    , Article Applied Soft Computing Journal ; Volume 71 , 2018 , Pages 277-290 ; 15684946 (ISSN) Osaba, E ; Ser, J. D ; Sadollah, A ; Bilbao, M. N ; Camacho, D ; Sharif University of Technology
    Abstract
    The water cycle algorithm (WCA) is a nature-inspired meta-heuristic recently contributed to the community in 2012, which finds its motivation in the natural surface runoff phase in water cycle process and on how streams and rivers flow into the sea. This method has been so far successfully applied to many engineering applications, spread over a wide variety of application fields. In this paper an enhanced discrete version of the WCA (coined as DWCA) is proposed for solving the Symmetric and Asymmetric Traveling Salesman Problem. Aimed at proving that the developed approach is a promising approximation method for solving this family of optimization problems, the designed solver has been...