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    Design and Modeling of a Solar Combined Cooling, Heating and Power System and it’s Validation with Empirical Results

    , M.Sc. Thesis Sharif University of Technology Yassaghi, Hamed (Author) ; Saboohi, Yadollah (Supervisor)
    Abstract
    Due to the growth of energy consumption the use of new technologies and efficient energy conversion is necessary. An example of efficient energy conversion technology is CCHP (Combined Cooling, Heating and Power). The aim of the present research work is to develop a model that could be applied for optimal design of a hybrid CCHP system which would be Solar Combined Cooling, Heating and Power (SCCHP). In order to do so,microturbine power system, cooling and heating equipment’s such as absorption system and heat exchanger and also solar collector have been considered as an integral part of the system. The objective of the application of the model has been to identify proper sizing of all... 

    Nonlinear Performance of 3-D Steel Structures by Scaled Nonlinear Dynamic Procedure

    , M.Sc. Thesis Sharif University of Technology Hashemian, Behdad (Author) ; Mofid, Masoud (Supervisor)
    Abstract
    It is well known that the most rigorous method to assess the performance and to predict the seismic demands of a structure subjected to earthquake is nonlinear time history analysis. However, this technique is accompanied by complexities and difficulties in evaluating the seismic demands of structures and requires superior knowledge and skill. As a result, in recent years, nonlinear static analysis has been proposed in performance based design procedures. One of the primary assumptions of nonlinear static procedures is that the behavior of a structure with multiple degrees of freedom (MDOF) subjected to seismic ground motion can be estimated from the response of an oscillator with a single... 

    , M.Sc. Thesis Sharif University of Technology Mohammad Alippour Ahari, Roua (Author) ; Eshghi, Koorosh (Supervisor)
    Abstract
    The focus of this research is to present a model to verify the acceptance of projects with time and cost dependency on the usage of equipments. Decision on these projects is based on a dynamic programming in which at each stage, the profit of available projects in this stage, equipment value and the best choice of future stage are decision keys. In other words, after the completion of a project, it should be decided between doing a project or selling the equipment and leaving the remaining projects. For each projects, there is a product network that includes projects jobs and operations. After accepting projects, equipments of the projects will not be renewed and the usage of the equipments... 

    Development of an Integrated Solar Energy System for a Typical Educational Building

    , M.Sc. Thesis Sharif University of Technology Motavaselian, Ali Mohammad (Author) ; Saboohi, Yadollah (Supervisor)
    Abstract
    In the present thesis, A Computer software has been developed to evaluate technical and economic aspects of photovoltaic systems, off-grid and on-grid configuration, in urban areas where the electricity grid is accessible. As a case study the building of Energy Engineering faculty with annual demand of electricity in lighting section equals to 80048 kWh was considered. Regarding incident radiation and PV system characteristics with the aid of utilizability concept, a technical evaluation has been performed then life-cycle saving index was considered as a criterion for choosing an optimum nominal size of the system. Results show that for current electricity tariff of educational buildings ... 

    Development of Transient Model of Fuel Consumption to Optimize IVT

    , M.Sc. Thesis Sharif University of Technology Ebadi, Mohammad (Author) ; Saadat Foumani, Mahmoud (Supervisor) ; Kazemzade Hannani, Siamak (Co-Advisor)
    Abstract
    Changes in the internal structure of engines for reducing fuel consumption has almost stopped. While changes in powertrain is a better way to reduce vehicle fuel consumption. Recently, infinitely variable transmissions or IVTs have attracted large attention of car manufacturers . In these systems, due to the continuous transmission ratio, engine speed is kept in a range which is the optimum fuel consumption speed range. Designing of these systems for each vehicle must be done according to the requirements of the vehicle and engine abilities. So, an exact model of engine fuel consumption for the design of these systems is required. One way of improving the accuracy of conventional models, is... 

    Modeling of the Flexible Instrument Inside the Vascular Environment for Its Motion Control in Minimally Invasive Procedures

    , M.Sc. Thesis Sharif University of Technology Rezazadeh, Taha (Author) ; Nejat Pishkenari, Hossein (Supervisor)
    Abstract
    Minimally invasive procedures are diagnostic or therapeutic methods that cause minimal injuries and side effects for patients. PCI is a common minimally invasive procedure for diagnosis and curing of cardiovascular disorders. In this procedure, the surgeon can have access to the cardiac vessels by a flexible instrument. However, motion control of this instrument inside the patient's body relies on surgeon's skills and in some cases, is time consuming so that the toxic effects of radiation on patient and surgical team increases. Magnetic flexible instruments are suggested to address this problem. Nevertheless, motion control of the flexible instrument inside the body still has many challenges... 

    A Train Sequencing and Stop Scheduling Model inDouble Track Railway Lines by hHybrid GRASP-VNS Meta-Heuristic

    , M.Sc. Thesis Sharif University of Technology Hassannayebi, Erfan (Author) ; Kianfar, Fereydoon (Supervisor)
    Abstract
    The train scheduling problem is one of the most important scheduling problems in the transportation systems. The goal of train scheduling problem is generating a feasible timetable which consists of train departure times and determining the best station to stop. Optimizing the railway capacity is one of the most important goals in train scheduling phase. The sequence of dispatching trains and stopping schedule are the main factors that can affect railway capacity on double track lines. In this thesis, a double-track train sequencing problem is studied in order to maximize the railway capacity, subject to a set of operational requirements. This research proposes a flexible flow shop... 

    A Meta-Heuristic Approach for a Special Class of Job Shop Scheduling Problem

    , M.Sc. Thesis Sharif University of Technology Behroozi, Mehdi (Author) ; Koorosh, Eshghi (Supervisor)
    Abstract
    The job shop scheduling problem is an important and applicable optimization problem and has been attracted by many researchers in recent decades. A huge amount of applications of job shop scheduling problem in industries and services has been found yet. During the last decade, the sequence dependent setup time constraint has been considered in many researches, but with respect to the knowledge of authors, very few of these researches have considered the inseparable setup. Furthermore, few of them have considered the release date assumption. In this thesis, the classical job shop scheduling problem and the inseparable sequence dependent setup time and release date constrained problem have... 

    Design and Implementation of an Auto-Grasping Algorithm for a Robotic Laparoscopic Instrument

    , M.Sc. Thesis Sharif University of Technology Amirkhani, Golchehr (Author) ; Farahmand, Farzam (Supervisor)
    Abstract
    The main goal of this project is to design and implementation of the tissue auto-grasping algorithm for a wristed laparoscopic instrument. In this algorithm, the difference between the pinch forces of two jaws was taken into account when the pull force direction corresponding to the rod instrument direction was changed. The term ‘Tissue auto-grasping’ means automatic adjustment of the pinch force corresponding to the pull force exerted on the tissue by the robotic surgical instrument, so that slip and exerting excessive force on the tissue are prevented. In this study, obtaining the pinch force is based on the proximal force-sensing technique. For this reason, the force model of wristed... 

    A fuzzy project buffer management algorithm: a case study in the construction of a renewable project

    , Article International Journal of Construction Management ; 2022 ; 15623599 (ISSN) Zohrehvandi, S ; Vanhoucke, M ; Khalilzadeh, M ; Amiri, M ; Shadrokh, S ; Sharif University of Technology
    Taylor and Francis Ltd  2022
    Abstract
    One of the major problems with projects is that they are not completed according to schedule. Uncertainty always exists at the heart of real-world project scheduling problems. This paper introduces a fuzzy project buffer management (FPBM) algorithm which is a combination of the adaptive procedure with resource tightness (APRT) and fuzzy failure mode and effects analysis (FFMEA) methods. This paper aims to present an efficient model for project buffer sizing by taking FFMEA into account to reach a more realistic schedule. In this research, for increasing the efficiency of the APRT method, the FFMEA technique is simultaneously applied with them. This research was carried out as a case study in... 

    Catalyst-free Friedel-Crafts alkylation of naphthols with nitrostyrenes in the presence of water

    , Article Tetrahedron Letters ; Volume 50, Issue 13 , 2009 , Pages 1441-1443 ; 00404039 (ISSN) Ziyaei Halimehjani, A ; Aryanasab, F ; Saidi, M. R ; Sharif University of Technology
    2009
    Abstract
    Accelerated Michael-type Friedel-Crafts alkylation of naphthols with nitrostyrenes in the presence of water is reported. The procedure is simple, catalyst-free, and affords good yields of the products. © 2009 Elsevier Ltd. All rights reserved  

    On the growth and photocatalytic activity of the vertically aligned ZnO nanorods grafted by CdS shells

    , Article Applied Surface Science ; Volume 273 , July , 2013 , Pages 391-398 ; 01694332 (ISSN) Zirak, M ; Moradlou, O ; Bayati, M. R ; Nien, Y. T ; Moshfegh, A. Z ; Sharif University of Technology
    2013
    Abstract
    We have studied systematically photocatalytic properties of the vertically aligned ZnO@CdS core-shell nanorods where the features were grown through a multistep procedure including sol-gel for the formation of ZnO seed layer, hydrothermal process to grow ZnO nanorods, and successive ion layer adsorption and reaction (SILAR) process to deposit CdS nanoshells onto the ZnO nanorods. Formation of the ZnO seed layer and vertically aligned ZnO nanorods (d ∼ 40 nm) with a hexagonal cross-section was confirmed by AFM and SEM imaging. Successful capping of ZnO nanorods with homogeneous CdS nanocrystallites (∼5 nm) was ascertained by HRTEM diffraction and imaging. Optical properties of the samples... 

    Numerical computation of compressible laminar flow with heat transfer in the entrance region of a pipe

    , Article 2008 ASME Summer Heat Transfer Conference, HT 2008, Jacksonville, FL, 10 August 2008 through 14 August 2008 ; Volume 3 , 2009 , Pages 445-454 ; 9780791848487 (ISBN) Ziaei Rad, M ; Nouri Broujerdi, A ; Seume, J ; Sharif University of Technology
    2009
    Abstract
    The authors' research work on pressure drop along gas transmission pipelines raised questions regarding the development length of the corresponding compressible flow and the effect of heat transfer in the entrance region on the pressure drop along the whole length of the pipe. In this paper, laminar, viscous, compressible flow in the entrance region of a pipe is investigated numerically in two dimensions. The numerical procedure is a finite-volume based finite-element method applied on unstructured grids. This combination together with a new method applied for boundary conditions allows accurate computation of the variables in the entrance region. The method is applied to some incompressible... 

    Numerical simulation of turbulent unsteady compressible pipe flow with heat transfer in the entrance region

    , Article International Conference 'Turbulent Mixing and Beyond', Trieste, 18 August 2007 through 26 August 2007 ; Volume T132 , December , 2008 ; 02811847 (ISSN) Ziaei Rad, M ; Nouri Broujerdi, A ; Sharif University of Technology
    2008
    Abstract
    In this paper, the compressible gas flow through a pipe subjected to wall heat flux in unsteady condition in the entrance region is investigated numerically. The coupled conservation equations governing turbulent compressible viscous flow in the developing region of a pipe are solved numerically under different thermal boundary conditions. The numerical procedure is a finite-volume-based finite-element method applied to unstructured grids. The convection terms are discretized by the well-defined Roe method, whereas the diffusion terms are discretized by a Galerkin finite-element formulation. The temporal terms are evaluated based on an explicit fourth-order Runge-Kutta scheme. The effect of... 

    Quantitative in vivo microsampling for pharmacokinetic studies based on an integrated solid-phase microextraction system

    , Article Analytical Chemistry ; Volume 79, Issue 12 , 2007 , Pages 4507-4513 ; 00032700 (ISSN) Zhang, X ; Eshaghi, A ; Musteata, F. M ; Ouyang, G ; Pawliszyn, J ; Sharif University of Technology
    2007
    Abstract
    An integrated microsampling approach based on solid-phase microextraction (SPME) was developed to provide a complete solution to highly efficient and accurate pharmacokinetic studies. The microsampling system included SPME probes that are made of poly(ethylene glycol) (PEG) and C18-bonded silica, a fast and efficient sampling strategy with accurate kinetic calibration, and a high-throughput desorption device based on a modified 96-well plate. The sampling system greatly improved the quantitative capability of SPME in two ways. First, the use of the C18-bonded silica/PEG fibers minimized the competition effect from analogues of the target analytes in a complicated sample matrix such as blood... 

    Amine modified magnetic polystyrene for extraction of drugs from urine samples

    , Article Journal of Chromatography A ; Volume 1602 , 2019 , Pages 107-116 ; 00219673 (ISSN) Zeinali, S ; Maleki, M ; Bagheri, H ; Sharif University of Technology
    Elsevier B.V  2019
    Abstract
    Polystyrene is one of the best candidates as the extracting medium due to its high stability in different media and acceptable extraction capability. However, the hydrophobic nature and low wettability of polystyrene limits its application to non–polar analytes. To resolve this limitation, in this project, amine groups were chemically attached to the surface of magnetic polystyrene. The resulting hydrophilic magnetic particles were expected to be capable of extracting both polar and non–polar analytes. Non–steroidal anti–inflammatory drugs (NSAIDs) were chosen for testing the applicability of modified magnetic polystyrene according to the importance of their analysis and also their wide... 

    Technique for online tracking of a utility harmonic impedance using by synchronising the measured samples

    , Article IET Generation, Transmission and Distribution ; Volume 10, Issue 5 , 2016 , Pages 1240-1247 ; 17518687 (ISSN) Zebardast, A ; Mokhtari, H ; Sharif University of Technology
    Institution of Engineering and Technology 
    Abstract
    Utility harmonic impedance estimation is an important stage for the study and control of electrical networks power quality such as harmonic sharing determination between a utility and a customer at a point of common coupling (PCC). In this estimation, non-invasive methods, as compared with invasive methods, are more desirable since they do not need to apply intentional disturbances to the power network and can work based on natural load fluctuations. The only concern about such methods is the method accuracy. These methods require simultaneous and synchronous measurements of the voltage and current at the PCC. However, one of the causes of error in the utility harmonic impedance measurement... 

    New method for assessing the utility harmonic impedance based on fuzzy logic

    , Article IET Generation, Transmission and Distribution ; Volume 11, Issue 10 , 2017 , Pages 2448-2456 ; 17518687 (ISSN) Zebardast, A ; Mokhtari, H ; Sharif University of Technology
    Abstract
    This study proposes a novel non-invasive method for estimating the utility harmonic impedance. Since the major concern about non-invasive methods is the dependency of the accuracy of the results on background harmonic fluctuations, proper measured samples are selected using a three-point data selection technique to increase the method accuracy. Then, a new non-invasive method for the evaluation of the utility harmonic impedance at a point of common coupling (PCC) based on fuzzy logic is presented. In the proposed method, fuzzy logic is applied to the constrained recursive least squares algorithm (CRLS) by designing a set of fuzzy if-then rules. Due to the changes in the quantities at a... 

    Joint approximate diagonalization of eigenmatrices as a high-throughput approach for analysis of hyphenated and comprehensive two-dimensional gas chromatographic data

    , Article Journal of Chromatography A ; Volume 1524 , 2017 , Pages 188-201 ; 00219673 (ISSN) Zarghani, M ; Parastar, H ; Sharif University of Technology
    Abstract
    The objective of the present work is development of joint approximate diagonalization of eigenmatrices (JADE) as a member of independent component analysis (ICA) family, for the analysis of gas chromatography-mass spectrometry (GC–MS) and comprehensive two-dimensional gas chromatography-mass spectrometry (GC × GC–MS) data to address incomplete separation problem occurred during the analysis of complex sample matrices. In this regard, simulated GC–MS and GC × GC–MS data sets with different number of components, different degree of overlap and noise were evaluated. In the case of simultaneous analysis of multiple samples, column-wise augmentation for GC–MS and column-wise super-augmentation... 

    Improving bactericidal performance of implant composite coatings by synergism between Melittin and tetracycline

    , Article Journal of Materials Science: Materials in Medicine ; Volume 33, Issue 6 , 2022 ; 09574530 (ISSN) Zarghami, V ; Ghorbani, M ; Pooshang Bagheri, K ; Shokrgozar, M. A ; Sharif University of Technology
    Springer  2022
    Abstract
    Methicillin resistance Staphylococcus aureus bacteria (MRSA) are serious hazards of bone implants. The present study was aimed to use the potential synergistic effects of Melittin and tetracycline to prevent MRSA associated bone implant infection. Chitosan/bioactive glass nanoparticles/tetracycline composite coatings were deposited on hydrothermally etched titanium substrate. Melittin was then coated on composite coatings by drop casting method. The surfaces were analyzed by FTIR, XRD, and SEM instruments. Tetracycline in coatings revealed multifunctional behaviors include bone regeneration and antibacterial activity. Releasing ALP enzyme from MC3T3 cells increased by tetracycline, so it is...