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Data Integration with Multiple Ontologies in Semantic Sensor Web
, M.Sc. Thesis Sharif University of Technology ; Abolhassani, Hassan (Supervisor)
Abstract
Sensor Observation Service (SOS) which is defined by Open Geospatial Consortium (OGC) Sensor Web Enablement group is a Web service specification in order to standardize the way sensors and sensor data are discovered and accessed on the Sensor Web. Multiple instances of this service can be implemented around the world, providing huge amount of data every moment. Each of these services operates in specific domain of knowledge (thematic), spatial and temporal dimensions. One way to reveal the underlying data over all of them is to provide an architecture for data integration to allow the user to query sensor data without the knowledge of the infrastructure components. In this research, a novel...
A Joint Inventory-Location Model in Service Systems
, M.Sc. Thesis Sharif University of Technology ; Shavandi, Hassan (Supervisor)
Abstract
In this research a joint location- inventory problem is analyzed. We assumed two kinds of inventories: fast-moving and slow-moving goods. These two kinds of goods can be observed in after sales service systems. In the real world fast moving goods are stocked in all dealers but for slow moving goods there is no force to stock in all dealers. Therefore an important decision in these systems is where and how much we should stock the slow moving goods and how each dealer can supplies its demand for slow moving goods. In this research we model this problem as a joint location-inventory model which locates some warehouses in the network to stock the slow moving goods and assigns the dealers to...
Simultaneous Navigation and Attitude Determination of a Reentry Head Using Magnetometer, Sun Sensor, Star Tracker, INS and Unscented Kalman Filter
, M.Sc. Thesis Sharif University of Technology ; Salarieh, Hassan (Supervisor)
Abstract
Control and guidance of a vehicle is vital for it to do its mission correctly. Guidance system and decisional algorithms used in it need exact information of instantaneous position, velocity, and attitude of the guided vehicle to determine and issue proper guiding commands.
Estimation algorithms and navigation sensors are two necessary tools for navigation. In the first section of present study, the reentry head equations of motion are derived and a 6-DOF simulation is done for it. In the second section, measurements of sensors will be simulated using results of the first section and existing reference models for sun position vector and earth magnetic field. The third section appertains...
Estimation algorithms and navigation sensors are two necessary tools for navigation. In the first section of present study, the reentry head equations of motion are derived and a 6-DOF simulation is done for it. In the second section, measurements of sensors will be simulated using results of the first section and existing reference models for sun position vector and earth magnetic field. The third section appertains...
Gaseous Slip Flow Mixed Convection in Vertical Microducts of Constant but Arbitrary Geometry
, M.Sc. Thesis Sharif University of Technology ; Saidi, Mohammad Hassan (Supervisor)
Abstract
In the study of heat transfer in micro-channels, free and force convections are two limit cases and these two methods of heat transfer are combined together generally, so to achieve the most accurate informations about the flow field they should be considered in combination. In the first part of the thesis the fully developed slip flow mixed convection in vertical micro-ducts of arbitrary shapes is investigated.Uniform axial heat flux and uniform peripheral wall temperature (H1) is considered. The method considered is analytical-numerical in which the governing equations and three of the boundary conditions are exactly satisfied but the remaining slip boundary condition on the duct wall...
An approximate analytical solution for electro-osmotic flow of power-law fluids in a planar microchannel
, Article Journal of Heat Transfer ; Volume 133, Issue 9 , July , 2011 ; 00221481 (ISSN) ; Fattahi, M ; Hassan Saidi, M ; Sharif University of Technology
2011
Abstract
The present investigation considers the fully developed electro-osmotic flow of power-law fluids in a planar microchannel subject to constant wall heat fluxes. Using an approximate velocity distribution, closed form expressions are obtained for the transverse distribution of temperature and Nusselt number. The approximate solution is found to be quite accurate, especially for the values of higher than ten for the dimensionless Debye-Huckel parameter where the exact values of Nusselt number are predicted. The results demonstrate that a higher value of the dimensionless Debye-Huckel parameter is accompanied by a higher Nusselt number for wall cooling, whereas the opposite is true for wall...
An Improvement on Test Driven Development
, M.Sc. Thesis Sharif University of Technology ; Mirian Hosseinabadi, Hassan (Supervisor)
Abstract
Less than a decade ago, Test Driven Development (TDD) emerged as a quality assurance approach and applied in agile software developments. In this method, test cases act as software development driver and a new piece of code is added just to satisfy the corresponding test case in the test repository. Although the results of applying TDD show its success in software quality promotion, but the method suffers from some limitations and shortcomings that make its usage hard in complicated and enterprise software projects, particularly in the industry. The goal of the following research is to mitigate the drawbacks of TDD and improve the method in order to make it more applicable for complicated...
Electrokinetic Flow in pH-Regulated Solid-State/Soft Micro-Nanochannels
,
Ph.D. Dissertation
Sharif University of Technology
;
Saeedi, Mohammad Hassan
(Supervisor)
;
Mousavi, Ali
(Co-Supervisor)
;
Sadeghi, Arman
(Co-Supervisor)
Abstract
In recent years, advances have been made in the field of miniaturization of the devices (in order to increase their efficiency, lessen the materials needed for the constructions and experiments, reduce costs and energy usage) resulting in the dramatic increase of surface to volume ratio in these devices. This progress has led to the dominance of surface forces which can be used to control very important interface phenomena having a special application such as electrokinetic. Using today’s manufacturing technology; it is possible to construct micro-nanochannels made from different materials such as silicon, glass, quartz, polydimethylsiloxane (PDMS), polymethyl methacrylate (PMMA) whose...
Radar Target Recognition Using Range Profiles Synthesized by Random Stepped Frequency Radar
, M.Sc. Thesis Sharif University of Technology ; Bastani, Mohammad Hassan (Supervisor)
Abstract
Target recognition is one of the widespread applications of today's radars that requires obtaining target signatures using radar measurements. High-resolution range profile (HRRP) is one of these signatures that provides a one-dimensional radar image of the target. There are several methods for radar target's HRRP synthesis , all of which require a large bandwidth. One of these methods is the use of stepped frequency radar. One of the advantages of this method is providing a wide bandwidth by sending pulses with small bandwidths, thus obviating the need for broadband receivers and transmitters and making implementation easier. In many cases HRRP of target is sparse, because the number of...
Transport Phenomena in Electrokinetically Generated Microflows
, Ph.D. Dissertation Sharif University of Technology ; Saeedi, Mohammad Hassan (Supervisor) ; Mozaffari, Ali Asghar (Supervisor) ; Chakraborty, Suman (Co-Advisor)
Abstract
This is a theoretical study on heat and mass transfer in electrokinetically driven microfluidic devices with particular consideration to the lab-on-a-chip (LOC) applications. Special attention is given to disclose the effects of the fluid rheology and the aspect ratio of the rectangular geometry on the surface reaction kinetics and the temperature rise due to the Joule heating. Along this line, two different viscoelastic constitutive equations namely PTT and FENE-P models along with the power-law viscosity model are being considered. The secondary aims also include exploring the influences of the fluid properties variations throughout the channel cross section on the hydrodynamic and thermal...
Simulation of wetting tendency of fluids with high density ratios using RK Lattice Boltzmann method
, Article 16th Asian Regional Conference on Soil Mechanics and Geotechnical Engineering, ARC 2019, 14 October 2019 through 18 October 2019 ; 2020 ; Pak, A ; Sadeghi, H ; Sharif University of Technology
Asian Regional Conference on Soil Mechanics and Geotechnical Engineering
2020
Abstract
Several lattice Boltzmann models for multi-phase flow have been developed, but few of them are capable of modeling fluid flows with high density ratio in the order of 1000. Therefore, an advanced chromodynamics, Rothmann-Keller (RK) type model is employed in current study, which can handle liquid-gas density ratio in the order of 1000 and viscosity ratio in the order of 100. Other distinctive characteristics of the proposed model are high stability, and capability of setting parameters such as surface tension independently. In spite of these benefits, the original RK model fails to model wetting tendency of the fluids. As a result, it is impossible to correctly simulate two-fluid phase flow...
Principles of Designing a Chair for Iranian Kitchen, Concerning Kansei Engineering Approach
, M.Sc. Thesis Sharif University of Technology ; Eshraghniaye Jahromi, Abdolhamid (Supervisor) ; Sadeghi Naeini, Hassan ($item.subfieldsMap.e)
Abstract
Iranian women spend a lot of times in the kitchen area in order to have good effects on the family. Unfortunately, we see many of them are suffering from body injuries and particularly musculoskeletal disorders in their middle ages. Many factors cause such problems among which awkward postures are mentioned and with identifying these postures, corrective solutions could be proposed.In this study, firstly, relationship of body injuries with working in the kitchen area is considered, awkward postures are identified and expedient actions are suggested. The aim of this study is chosen designing a suitable task chair for kitchen among the proposed solutions. Then, chair specifications are...
Mechanical behavior during aging of plastically deformed AA6061-SiCp composite in different temperatures
, Article Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications ; Volume 226, Issue 4 , 2012 , Pages 322-329 ; 14644207 (ISSN) ; Serajzadeh, S
SAGE
2012
Abstract
In this study, the kinetics of aging in AA6061 and AA6061 with 5% volume fraction SiCp were studied and compared. The composite was first produced and homogenized using stir casting technique followed by hot extrusion with the ratio of 18:1. Then, both AA6061 and the composite were aged at three different temperatures including room temperature, 170 °C and 240 °C, while mechanical properties during aging were evaluated employing hardness measurements and tensile testing. Moreover, in order to assess the effect of plastic deformation on the kinetics of aging, a series of samples were first deformed by equal-channel angular pressing immediately after solution treatment and then aged in the...
Electroosmotic flow and ionic conductance in a pH-regulated rectangular nanochannel
, Article Physics of Fluids ; Volume 29, Issue 6 , 2017 ; 10706631 (ISSN) ; Saidi, M. H ; Sadeghi, A ; Sharif University of Technology
2017
Abstract
Infinite series solutions are obtained for electrical potential, electroosmotic velocity, ionic conductance, and surface physicochemical properties of long pH-regulated rectangular nanochannels of low surface potential utilizing the double finite Fourier transform method. Closed form expressions are also obtained for channels of large height to width ratio for which the depthwise variations vanish. Neglecting the Stern layer impact, the effects of EDL (Electric Double Layer) overlap, multiple ionic species, and association/dissociation reactions on the surface are all taken into account. Moreover, finite-element-based numerical simulations are conducted to account for the end effects as well...
Geotechnical characterization and collapsibility of a natural dispersive loess
, Article Engineering Geology ; Volume 250 , 2019 , Pages 89-100 ; 00137952 (ISSN) ; Kiani, M ; Sadeghi, M ; Jafarzadeh, F ; Sharif University of Technology
Elsevier B.V
2019
Abstract
During preliminary investigation phase of the national Chabahar-Zahedan railway line, serious geotechnical problems including non-uniform settlements, tensile cracks, and local collapse were reported in parts of the path near the coastline. A follow-up field investigation revealed that the in-situ soil at construction site has a metastable structure being sensitive to saturation and loading. Therefore, a comprehensive series of physical, chemical, electro-chemical, and geotechnical tests were conducted to classify and characterize the soil properties and behavior in its natural state. The natural soil was classified as a clayey loess with moderately dispersive to dispersive characteristics....
Geometry effect on electrokinetic flow and ionic conductance in pH-regulated nanochannels
, Article Physics of Fluids ; Volume 29, Issue 12 , 2017 ; 10706631 (ISSN) ; Saidi, M. H ; Moosavi, A ; Sadeghi, A ; Sharif University of Technology
2017
Abstract
Semi-analytical solutions are obtained for the electrical potential, electroosmotic velocity, ionic conductance, and surface physicochemical properties associated with long pH-regulated nanochannels of arbitrary but constant cross-sectional area. The effects of electric double layer overlap, multiple ionic species, and surface association/dissociation reactions are all taken into account, assuming low surface potentials. The method of analysis includes series solutions which the pertinent coefficients are obtained by applying the wall boundary conditions using either of the least-squares or point matching techniques. Although the procedure is general enough to be applied to almost any...
Unsteady solute dispersion by electrokinetic flow in a polyelectrolyte layer-grafted rectangular microchannel with wall absorption
, Article Journal of Fluid Mechanics ; Volume 887 , 2020 ; Saidi, M. H ; Moosavi, A ; Sadeghi, A ; Sharif University of Technology
Cambridge University Press
2020
Abstract
The dispersion of a neutral solute band by electrokinetic flow in polyelectrolyte layer (PEL)-grafted rectangular/slit microchannels is theoretically studied. The flow is assumed to be both steady and fully developed and a first-order irreversible reaction is considered at the wall to account for probable surface adsorption of solutes. Considering low electric potentials, analytical solutions are obtained for electric potential, fluid velocity and solute concentration. Special solutions are also obtained for the case without wall adsorption. To track the dispersion properties of the solute band, the generalized dispersion model is adopted by considering the exchange, the convection and the...
Dispersivity, collapsibility and microstructure of a natural dispersive loess from Iran
, Article 16th Asian Regional Conference on Soil Mechanics and Geotechnical Engineering, ARC 2019, 14 October 2019 through 18 October 2019 ; 2020 ; Nasiri, H ; Panahi, P. A ; Sadeghi, M ; Sharif University of Technology
Asian Regional Conference on Soil Mechanics and Geotechnical Engineering
2020
Abstract
A new type of collapsible soil was encountered in Southern Iran and caused some serious technical problems including subsidence, collapse and sinkholes during the construction of Zahedan-Chabahar railway. Field observations indicated that in-situ soil contains excessive amount of salts resulting in dispersive features in response to seepage forces in addition to its collapsibility. Therefore, a systematic research plan including field sampling and laboratory testing was carried out to investigate the observed geotechnical features. Results of physio-chemical tests revealed the dominance of Sodium in excess of 70% relative to total dissolved salts, which results in high dispersive potential....
Structural Design of a Launch Vehicle with Reusable First Stage
, M.Sc. Thesis Sharif University of Technology ; Haddadpour, Hassan (Supervisor)
Abstract
Aerodynamics loads and aeroheating during reentry, are one of the challenging issues in designing One of the main challenges in the design and application of reusable spacecrafts is the aerodynamic and thermal loads acting on their structures during reentry into the atmosphere. For this reason, all the concepts/prototypes presented in the 20th century were either not fully reusable, or were partially canceled, or did not have economic justification. In this report, the aerodynamic loads on the first stage of a launch vehicle during the launch and return phases have been investigated. Due to the fact that the main part of the first stage of the vehicle includes fuel and oxidizer tanks, the...
Modified carrageenan. 5. Preparation, swelling behavior, salt- and pH-sensitivity of partially hydrolyzed crosslinked carrageenan-graft-polymethacrylamide superabsorbent hydrogel [electronic resource]
, Article Polymers for Advanced Technologies ; Volume 15, Issue 11, pages 645–653, November 2004 ; Sadeghi, M ; Hosseinzadeh, H
Abstract
The polysaccharide, kappa-carrageenan (κC) was chemically modified to achieve a novel superabsorbent hydrogel via graft copolymerization of methacrylamide (MAM) onto the substrate followed by alkaline hydrolysis. Ammonium persulfate (APS) and N,N′-methylene bisacrylamide (MBA) were used as a free-radical initiator and a crosslinker, respectively. The saponification reaction was carried out using sodium hydroxide aqueous solution. Either κC-g-PMAM or hydrolyzed κC-g-PMAM (PMAM: polymethacrylamide) was characterized by FT-IR spectroscopy. The effect of grafting variables (i.e. concentration of MBA, MAM, and APS) and alkaline hydrolysis conditions (i.e. NaOH concentration, hydrolysis time and...
Optimizing a bi-objective inventory model of a three-echelon supply chain using a tuned hybrid bat algorithm
, Article Transportation Research Part E: Logistics and Transportation Review ; Vol. 70, issue. 1 , October , 2014 , p. 274-292 ; Mousavi, S. M ; Niaki, S. T. A ; Sadeghi, S ; Sharif University of Technology
2014
Abstract
This paper presents a bi-objective VMI problem in a single manufacturer-single vendor multi-retailer (SM-SV-MR) supply chain, which a redundancy allocation problem is incorporated. In the hybridized problem, a manufacturer produces a single item using several machines that work in series, and stores it in a warehouse to replenish one vendor who delivers it to several retailers using the shortest possible route. A novel meta-heuristic, called hybrid bat algorithm (HBA), with calibrated parameters is utilized to find a near-optimum solution. To show the efficiency of HBA, the results are compared to the ones using the traditional BA and a genetic algorithm