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Gravity-driven thin liquid films over topographical substrates
, Article European Physical Journal E ; Volume 36, Issue 6 , 2013 ; 12928941 (ISSN) ; Moosavi, A ; Esmaili, E ; Sharif University of Technology
2013
Abstract
We investigate the time-dependent evolution of thin liquid films over inclined substrates using a multi-component lattice Boltzmann algorithm. Substrates with and without grooves are considered and the effects of the inclination angle on the dynamics and the coating of the substrates are studied. Our results indicate that the dynamics is enhanced and the ridge height and its displacement are increased by increasing the inclination angle. However, by increasing the inclination angle the maximum depth that can be successfully coated is reduced. Also, although for any given groove depth the width should be larger than a critical value for successful coating, the critical width decreases for...
Pseudo-dirac neutrino scenario: Cosmic neutrinos at neutrino telescopes
, Article Physical Review D - Particles, Fields, Gravitation and Cosmology ; Volume 81, Issue 1 , 2010 ; 15507998 (ISSN) ; Sharif University of Technology
2010
Abstract
Within the "pseudo-Dirac" scenario for massive neutrinos the existence of sterile neutrinos which are almost degenerate in mass with the active ones is hypothesized. The presence of these sterile neutrinos can affect the flavor composition of cosmic neutrinos arriving at Earth after traveling large distances from astrophysical objects. We examine the prospects of neutrino telescopes such as IceCube to probe the very tiny mass squared differences 10-12eV2>Δm2>10-19eV2, by analyzing the ratio of μ-track events to showerlike events. Considering various sources of uncertainties which enter this analysis, we examine the capability of neutrino telescopes to verify the validity of the pseudo-Dirac...
Cosmic neutrinos at IceCube: θ13, δ and initial flavor composition
, Article Journal of Physics: Conference Series ; Volume 203 , 2010 ; 17426588 (ISSN) ; Sharif University of Technology
2010
Abstract
We discuss the prospect of extracting the values of the mixing parameters δ and θ13 through the detection of cosmic neutrinos in the planned and forthcoming neutrino telescopes. We take the ratio of the μ-track to shower-like events, R, as the realistic quantity that can be measured in the neutrino telescopes. We take into account several sources of uncertainties that enter the analysis. We then examine to what extent the deviation of the initial flavor composition from we : w μ : wτ 1 : 2 : 0 can be tested
Existence and Uniqueness of Solution for Two Free Boundary Problems Modelling Tumor Growth
,
M.Sc. Thesis
Sharif University of Technology
;
Hesaaraki, Mahmoud
(Supervisor)
Abstract
This thesis is based on articles [18,15]. Zhao [18] has studied a free boundary problem modeling the growth of tumors with drug application. In this model live cells are two kindes: proliferative cells and quiescent cells. This model consists of two nonlinear second-order parabolic equations describing the diffusion of nutrient and drug concentration, and three nonlinear first-order hyperbolic equations describing the evolution of proliferative cells, quiescent cells and dead cells. He has proved that this free boundary problem has a unique global solution. Tao and Chen [15] have studied another free boundary problem modelling the growth of an avascular tumour with drug application. The...
Oscillation of neutrinos produced by the annihilation of dark matter inside the Sun
, Article Physical Review D - Particles, Fields, Gravitation and Cosmology ; Volume 81, Issue 11 , June , 2010 ; 15507998 (ISSN) ; Farzan, Y ; Sharif University of Technology
2010
Abstract
The annihilation of dark matter particles captured by the Sun can lead to a neutrino flux observable in neutrino detectors. Considering the fact that these dark matter particles are nonrelativistic, if a pair of dark matter annihilates to a neutrino pair, the spectrum of neutrinos will be monochromatic. We show that in this case, even after averaging over the production point inside the Sun, the oscillatory terms of the oscillation probability do not average to zero. This leads to interesting observable features in the annual variation of the number of muon track events. We show that smearing of the spectrum due to thermal distribution of dark matter inside the Sun is too small to wash out...
An analysis of cosmic neutrinos: flavor composition at source and neutrino mixing parameters
, Article Nuclear Physics B ; Volume 821, Issue 1-2 , 2009 , Pages 197-214 ; 05503213 (ISSN) ; Farzan, Y ; Sharif University of Technology
2009
Abstract
We examine the feasibility of deriving neutrino mixing parameters δ and θ13 from the cosmic neutrino flavor composition under the assumption that the flavor ratios of the cosmic neutrinos at the source were Fνe + Fover(ν, ̄)e : Fνμ + Fover(ν, ̄)μ : Fντ + Fover(ν, ̄)τ = 1 : 2 : 0. We analyze various uncertainties that enter the derivation of δ and θ13 from the ratio of the shower-like to μ-tracks events which is the only realistic source of information on the flavor composition at neutrino telescopes such as ICECUBE. We then examine to what extent the deviation of the initial flavor ratio from 1 : 2 : 0 can be tested by measurement of this ratio at neutrino telescopes taking into account...
A new class of invariants in the lepton sector
, Article Nuclear Physics B ; Volume 811, Issue 1-2 , 2009 , Pages 98-108 ; 05503213 (ISSN) ; Farzan, Y ; Sharif University of Technology
2009
Abstract
We construct a new set of combinations from the mass matrices of the charged leptons and neutrinos that are invariant under basis transformation, hereafter the invariants. We use these invariants to study various symmetries and neutrino mass textures in a basis independent way. In particular, we show that by using these invariants the ansatz such as μ - τ exchange and reflection symmetries, various texture zeros and flavor symmetries can be expressed in a general basis. © 2008 Elsevier B.V. All rights reserved
Analytical and Numerical Study of Dynamics of Wettability Driven Droplets in Smooth And Corrugated Channels
, M.Sc. Thesis Sharif University of Technology ; Moosavi, Ali (Supervisor)
Abstract
We studied dynamics of droplets inside channels under surface forces created by chemicalsteps on the channel walls. A multi-component Shan-Chen lattice Boltzmann method isused for this purpose.The effects of parameters such as the channel height, viscosity anddensity ratios on the results were investigated for homogeneous and grooved substrates. Alsoan analytical solution was developed for droplets under chemical heterogeneities in channels with smooth surfaces. The solution considers a general condition, namely, asymmetry of the contact angles on the top and bottom walls, the viscosity of the gas as the second fluid and the effect of the channel height. Then using Shan-Chen lattice...
Mahak: A test collection for evaluation of farsi information retrieval systems
, Article 2007 IEEE/ACS International Conference on Computer Systems and Applications, AICCSA 2007, Amman, 13 May 2007 through 16 May 2007 ; 2007 , Pages 639-644 ; 1424410312 (ISBN); 9781424410316 (ISBN) ; Abolhassani, H ; Neshati, M ; Behrangi, E ; Rostami, A ; Mohammadi Nasiri, M ; Sharif University of Technology
2007
Abstract
Currently there is no standard test collection for evaluation of Farsi information retrieval systems. In this paper we introduce Mahak, the first complete test collection generally available for evaluating Farsi information retrieval systems. We also discuss our construction process in detail. As a goal, we hope that Mahak will foster the development of Farsi information retrieval systems. © 2007 IEEE
A categorization scheme for semantic web search engines
, Article IEEE International Conference on Computer Systems and Applications, 2006, Sharjah, 8 March 2006 through 8 March 2006 ; Volume 2006 , 2006 , Pages 171-178 ; 1424402123 (ISBN); 9781424402120 (ISBN) ; Abolhassani, H ; Sharif University of Technology
IEEE Computer Society
2006
Abstract
Semantic web search engines are evolving and many prototype systems and some implementation have been developed. However, there are some different views on what a semantic search engine should do. In this paper, a categorization scheme for semantic web search engines are introduced and elaborated. For each category, its components are described according to a proposed general architecture and various approaches employed in these components are discussed. We also propose some factors to evaluate systems in each category. © 2006 IEEE
The dynamics of wettability driven droplets in smooth and corrugated microchannels
, Article Journal of Statistical Mechanics: Theory and Experiment ; Volume 2012, Issue 10 , 2012 ; 17425468 (ISSN) ; Moosavi, A ; Mazloomi, A ; Sharif University of Technology
IOP
2012
Abstract
A multi-component lattice Boltzmann scheme is used to investigate the dynamics of a wettability driven droplet within a microchannel. The driving force for the motion is created by a stepwise change in the wettability of the channel walls. Moreover, an analytical solution is developed for evaluation of the dynamics of the droplet inside the channel. The effects of various parameters such as the height of the channel, the wetting pattern of the channel walls, the viscosity and the density ratio on the dynamics are studied. Also, the effect of grooves of different sizes on the channel surfaces on the dynamics of the droplet is investigated for both hydrophilic and hydrophobic surfaces....
Nonlinear cuffless blood pressure estimation of healthy subjects using pulse transit time and arrival time
, Article IEEE Transactions on Instrumentation and Measurement ; Volume 66, Issue 12 , 2017 , Pages 3299-3308 ; 00189456 (ISSN) ; Kachuee, M ; Shabany, M ; Sharif University of Technology
2017
Abstract
This paper presents a novel blood pressure (BP) estimation method based on pulse transit time (PTT) and pulse arrival time (PAT) to estimate the systolic BP (SBP) and the diastolic BP (DBP). A data acquisition hardware is designed for high-resolution sampling of phonocardiogram (PCG), photoplethysmogram, and electrocardiogram (ECG). PCG and ECG perform as the proximal timing reference to obtain PTT and PAT indices, respectively. In order to derive a BP estimator model, a calibration procedure, including a supervised physical exercise, is conducted for each individual, which causes changes in their BP, and then, a number of reference BPs are measured alongside the acquisition of the signals...
Cosmic Neutrinos at Neutrino Telescopes CP-violation, Source Properties and Beyond the Standard Model Physics
, Ph.D. Dissertation Sharif University of Technology ; Farzan, Yasaman (Supervisor)
Abstract
In this thesis, we studied the oscillation of neutrino flavors and the measurement of mixing parameters through the detection of cosmic neutrinos at neutrino telescopes. Most of the astrophysical explosions predict the emission of neutrino flux and kilometer-scale detectors are under construction for the observation of these neutrinos. Detection of astrophysical neutrinos opens a new window to understand the neutrino properties and also the properties of astrophysical sources.In this thesis first we review the phenomenology of neutrino flavor oscillation and characteristics of neutrino mass matrix. By introducing a new class of invariants (under general transformation of lepton fields bases)...
Platforms Free Fall Lifeboat design, Analysis and Modification
, M.Sc. Thesis Sharif University of Technology ; Abbaspoor Tehranifard, Majid (Supervisor)
Abstract
The purpose of this study was to design a Free Fall Lifeboats body for offshore platforms, then hydrostatic and hydrodynamic analyzes, focusing on the aircavity formation on the back of the boat. In the first section, previous studies and a history of this has been discussed. Then the free fall bases are described along with the various stages of launching the Free Fall Lifeboat. In the next section, the Free Fall Lifeboat's body was designed and then analyzed and lunching procces has been simulated using the star-ccm+ software. the boat with seven different parameters is solved under the assumption that the air is incompressible, in which the primary conditions are the water entry angle...
Non-invasive blood pressure estimation using phonocardiogram
, Article Proceedings - IEEE International Symposium on Circuits and Systems, 28 May 2017 through 31 May 2017 ; 2017 ; 02714310 (ISSN) ; 9781467368520 (ISBN) ; Kachuee, M ; Shabany, M ; Sharif University of Technology
2017
Abstract
This paper presents a novel approach based on pulse transit time (PTT) for the estimation of blood pressure (BP). In order to achieve this goal, a data acquisition hardware is designed for high-resolution sampling of phonocardiogram (PCG) and photoplethysmogram (PPG). These two signals can derive PTT values. Meanwhile, a force-sensing resistor (FSR) is placed under the cuff of the BP reference device to mark the moments of measurements accurately via recording instantaneous cuff pressure. For deriving the PTT-BP models, a calibration procedure including a supervised physical exercise is conducted for each individual. The proposed method is evaluated on 24 subjects. The final results prove...
BlogDisc: A system for automatic discovery and accumulation of persian blogs
, Article 2006 International Conference on Systems, Computing Sciences and Software Engineering, SCSS 2006, Part of the International Joint Conferences on Computer, Information, and Systems Sciences, and Engineering, CISSE 2006, 4 December 2006 through 14 December 2006 ; 2007 , Pages 269-273 ; 9781402062636 (ISBN) ; Abolhassani, H ; Abbassi, Z ; Sharif University of Technology
2007
Abstract
One of the important elements of the new generation of the Web is the emergence of blogs. Currently a considerable number of users are creating content using blogs. Although Persian blogs have a short history, they have improved significantly during this short period. Because of fundamental differences between Persian and other languages, limited work has been done to analyze Persian blogs. In this work, a system named BlogDisc for automatic discovery and accumulation of Persian blogs is developed. This system uses content as well as link structure of the blogs. As an important part of this research, we propose an algorithm to recognize blogs that are not hosted on special blog hosts. © 2007...
Optimisation of SBR Systems in Treating Mono-Ethylene –Glycol Wastewaters
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor)
Abstract
In the present study , operation of a laboratory scale sequencing batch reactor (SBR) was evaluated to treatment of synthetic wastewaters containing ethylene glycol. Studies carried out with a plexiglass bioreactor whith effective volume of 18 lit.Aeration was supplied via two air diffusers that set at the bottom of the reactor. Synthestic wastewater containing ethylene glycol and molasses as carbon source and other nutrient such as diammonium hydrogen phosphate as phosphor source and urea as nitrogen source for biological activities was composed at the laboratory. To optimization of this reactor three parameters – aeration time, chemical oxygen demand and sudden change in arganic loading...
Assessing ITIL Maturity to Business-IT Strategic Alignment
, M.Sc. Thesis Sharif University of Technology ; Shadrokh, Shahram (Supervisor)
Abstract
The literature suggests that organizations cannot be competitive if their business and information technology strategies are not aligned. Yet achieving strategic alignment continues to be a major concern for business executives. A number of alignment models have been offered in the literature, primary among them the Strategic Alignment model (SAM), Strategic Alignment Maturity model, and IT Governance (via ITIL). The Information Technology Infrastructure Library (ITIL) presents a comprehensive set of guidelines for defining, designing, implementing and maintaining IT Service Management processes. It provides platform that can be used to leverage complementary effects between IT and business...
Hydraulic performance of labyrinth side weirs using vanes or piles
, Article Proceedings of the Institution of Civil Engineers: Water Management ; Volume 164, Issue 5 , 2011 , Pages 229-241 ; 17417589 (ISSN) ; Borghei, S. M ; Esmaili, H ; Sharif University of Technology
2011
Abstract
In the present study, methods for improving the hydraulic performance of labyrinth side weirs in a rectangular channel are reported based on model experimentation. For this purpose different arrangements and configurations of groups of guide vane plates and piles in the side weir flow field were tested. Experiments were conducted on labyrinth side weirs of different lengths and sill heights fitted in the test section of a rectangular glass-walled channel. Depths of flow were measured in both longitudinal and crosswise directions at regular intervals and their profiles were studied. It was found that the discharge coefficient of the labyrinth side weirs under these conditions gave...
Improving ITIL strategic alignment approach using COBIT framework
, Article Proceedings of the International Conference on Electronic Business (ICEB), 1 December 2010 through 4 December 2010, Shanghai ; 2010 , Pages 490-494 ; 16830040 (ISSN) ; Gardesh, H ; Sikari, S. S ; Sharif University of Technology
2010
Abstract
IT Governance provides a business focus to enable alignment between business and IT objectives at high level COBIT framework and focused on IT operational levels, ITIL standard. COBIT and ITIL are not mutually exclusive and can be combined to provide a powerful IT governance, control and best-practice framework in IT service management. So ITIL business-IT strategic alignment perspective could be improved using COBIT framework. Focusing on COBIT processes which support (primarily and secondarily) strategic alignment, in this paper, first, we map COBIT 4.1 to ITIL v3 to identify how ITIL cover COBIT control objectives. Furthermore, based on control objectives which are not completely...