Loading...
Search for:
triangular
0.006 seconds
Total 56 records
Buckling behavior of composite triangular plates
, Article International Journal of GEOMATE ; Volume 2, Issue 2 , 2012 , Pages 253-260 ; 21862982 (ISSN) ; Heydarnia, E ; Amani, P ; Sharif University of Technology
GEOMATE International Society
2012
Abstract
This paper is to do a brief research on the buckling behavior of composite triangular plates with various edge boundary conditions and in-plane loads. It may be regarded as a right and simple numerical method for the analysis of composite triangular thin plate using the natural Area coordinates. Previous studies on the solution of triangular plates with different boundary conditions were mostly based on the Rayleigh-Ritz principle which is performed in the Cartesian coordinate. In this method, the energy functional of a general triangular plate is derived and the Rayleigh-Ritz method is utilized to derive the governing eigenvalue equation for the buckling problem. The geometry is presented...
Simultaneousely Triangularization of Families of Compact Operators on the Banach Spaces
, M.Sc. Thesis Sharif University of Technology ; Fanai, Hamid Reza (Supervisor)
Abstract
Simultaneous triangulation of matrices is a subject with a rich literature. There are many well known theorems available, such as McCoy theorem or Burnsides. In the nite dimensional case since the all the topologies on vector spaces are the same, there is a little bit diculty and most of the arguments are from linear algebra. In this thesis we study the simultaneous triangulation of sub algebras of K(X),with X a innite dimensional Banach space. We will give a denition of simultaneous triangulation which is independent of the notion of Basis and totally relies on Invariant subspaces. This denition coincides with the denition of simultaneous triangulation in nite dimensional case. Then we will...
The triangular pyramid: Routing and topological properties
, Article Information Sciences ; Vol. 180, issue. 11 , 2010 , p. 2328-2339 ; ISSN: 00200255 ; Sarbazi-Azad, H ; Sharif University of Technology
Abstract
In this paper, a new topology for multicomputer interconnection networks, based on triangular mesh, is proposed. The new network, referred to as the triangular pyramid (or tripy for short), has L levels of triangular mesh. We study some basic important properties of the proposed network as well as introduce a routing algorithm for the tripy network based on the routing of triangular meshes. We prove that this form of pyramidal network is Hamiltonian, Hamiltonian-connected, and pancyclic. We also prove that the proposed network is 6-colorable and conduct a brief comparison of the tripy and its traditional pyramid counterpart. Our results show that the proposed network has higher scalability,...
The triangular pyramid: Routing and topological properties
, Article Information Sciences ; Volume 180, Issue 11 , June , 2010 , Pages 2328-2339 ; 00200255 (ISSN) ; Sarbazi Azad, H ; Sharif University of Technology
2010
Abstract
In this paper, a new topology for multicomputer interconnection networks, based on triangular mesh, is proposed. The new network, referred to as the triangular pyramid (or tripy for short), has L levels of triangular mesh. We study some basic important properties of the proposed network as well as introduce a routing algorithm for the tripy network based on the routing of triangular meshes. We prove that this form of pyramidal network is Hamiltonian, Hamiltonian-connected, and pancyclic. We also prove that the proposed network is 6-colorable and conduct a brief comparison of the tripy and its traditional pyramid counterpart. Our results show that the proposed network has higher scalability,...
Conditions on decomposing linear systems with more than one matrix to block triangular or diagonal form
, Article IEEE Transactions on Automatic Control ; Volume 60, Issue 1 , May , 2015 , Pages 233-239 ; 00189286 (ISSN) ; Haeri, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
This technical note provides necessary and sufficient conditions to determine that a linear system with more than one matrix in its state-space representation can be decomposed into cascade or separate sub-systems. In order to perform such decomposition, one needs to determine a linear transformation matrix. Furthermore, the given conditions are adapted to a simple but effective condition to derive all possible scalar sub-systems for a given linear system. Numerical examples are provided to demonstrate the applicability of the presented results
Effects of after-body on the FIV of a right-angle triangular cylinder in comparison to circular, square, and diamond cross-sections
, Article Ships and Offshore Structures ; 2018 ; 17445302 (ISSN) ; Naeeni, T. O ; Zeinoddini, M ; Seif, M. S ; Dolatshahi Pirooz, M ; Sharif University of Technology
Taylor and Francis Ltd
2018
Abstract
This in-water experimental study deals with the effects of the after-body on the FIV response of round and sharp edge cylinders. Different circular, square, diamond, and right-angle isosceles triangular cross-sections are investigated. The triangular cylinder is examined in four different symmetrical and unsymmetrical configurations with respect to the incident flow. The current towing tank experiments form a basis for the feasibility study of the isosceles triangular cylinders for FIV energy converters. The results indicate that the cylinders with a flat side perpendicular to the flow have a galloping type of response. In contrast, the cylinders with a sharp vertex pointing the flow show a...
Effects of after-body on the FIV of a right-angle triangular cylinder in comparison to circular, square, and diamond cross-sections
, Article Ships and Offshore Structures ; Volume 14, Issue 6 , 2019 , Pages 589-599 ; 17445302 (ISSN) ; Naeeni, S. T. O ; Zeinoddini, M ; Seif, M. S ; Dolatshahi Pirooz, M ; Sharif University of Technology
Taylor and Francis Ltd
2019
Abstract
This in-water experimental study deals with the effects of the after-body on the FIV response of round and sharp edge cylinders. Different circular, square, diamond, and right-angle isosceles triangular cross-sections are investigated. The triangular cylinder is examined in four different symmetrical and unsymmetrical configurations with respect to the incident flow. The current towing tank experiments form a basis for the feasibility study of the isosceles triangular cylinders for FIV energy converters. The results indicate that the cylinders with a flat side perpendicular to the flow have a galloping type of response. In contrast, the cylinders with a sharp vertex pointing the flow show a...
Laboratory Evaluation of Multiplex Asymmetrical Triangular Sharp Edge Weir
, M.Sc. Thesis Sharif University of Technology ; Abrishamchi, Ahmad (Supervisor)
Abstract
This project is about crest triangular weirs. The discharge is a function of triangular angle and head of the water. There are so many projects that is about the effect of various parameters on the discharge of weir. In some places we can not use just one symmetric weir so we have to use multi weirs. Because of the lack of information in multiasymmetrical weirs, the goal of this project in studing multi triangular weirs in laboratory. We used the civil engeneering department of sharif university chanel that is 148 cm in width and 40 cm in height. In this project we used three 60, two 90 and two 45 triangular weirs that instaleed singular,double and triapple in various position in width. In...
Galerkin and Generalized Least Squares finite element: A comparative study for multi-group diffusion solvers
, Article Progress in Nuclear Energy ; Volume 85 , 2015 , Pages 473-490 ; 01491970 (ISSN) ; Saadatian Derakhshandeh, F ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
Abstract In this paper, the solution of multi-group neutron/adjoint equation using Finite Element Method (FEM) for hexagonal and rectangular reactor cores is reported. The spatial discretization of the neutron diffusion equation is performed based on two different Finite Element Methods (FEMs) using unstructured triangular elements generated by Gambit software. Calculations are performed using Galerkin and Generalized Least Squares FEMs; based on which results are compared. Using the power iteration method for the neutron and adjoint calculations, the neutron and adjoint flux distributions with the corresponding eigenvalues are obtained. The results are then validated against the valid...
An Intelligent Triangular Pattern Recognition in Stock Price Charts
, M.Sc. Thesis Sharif University of Technology ; Fazli, Mohammad Amin (Supervisor)
Abstract
Stock price patterns are a technical analysis approach to forecast future trends with tremendous practical benefits. However, the current algorithms solely rely on machine learning techniques and deep neural networks which could be a problem in countries where data sets such as these are not available. We propose an algorithm based on geometry and mathematics for this problem, leading to an O(n^3logn + n^2k) complexity, where k is the number of triangular patterns
Construction of Dirac points using triangular supercrystals
, Article Applied Physics A: Materials Science and Processing ; Volume 115, Issue 2 , May , 2014 , Pages 581-587 ; ISSN: 09478396 ; Mohajeri, R ; Khorasani, S ; Sharif University of Technology
Abstract
We show a methodology for how to construct Dirac points that occur at the corners of Brillouin zone as the Photonic counterparts of graphene. We use a triangular lattice with circular holes on a silicon substrate to create a Coupled Photonic Crystal Resonator Array (CPCRA) which its cavity resonators play the role of carbon atoms in graphene. At first we draw the band structure of our CPCRA using the tight-binding method. For this purpose we first designed a cavity which its resonant frequency is approximately at the middle of the first H-polarization band gap of the basis triangular lattice. Then we obtained dipole modes and magnetic field distribution of this cavity using the Finite...
Recursive linear and differential cryptanalysis of ultralightweight authentication protocols
, Article IEEE Transactions on Information Forensics and Security ; Volume 8, Issue 7 , 2013 , Pages 1140-1151 ; 15566013 (ISSN) ; Salmasizadeh, M ; Aref, M. R ; Sharif University of Technology
2013
Abstract
Privacy is faced with serious challenges in the ubiquitous computing world. In order to handle this problem, some researchers in recent years have focused on design and analysis of privacy-friendly ultralightweight authentication protocols. Although the majority of these schemes have been broken to a greater or lesser extent, most of these attacks are based on ad-hoc methods that are not extensible to a large class of ultralightweight protocols. So this research area still suffers from the lack of structured cryptanalysis and evaluation methods. In this paper, we introduce new frameworks for full disclosure attacks on ultralightweight authentication protocols based on new concepts of...
Continuous size-based focusing and bifurcating microparticle streams using a negative dielectrophoretic system
, Article Microfluidics and Nanofluidics ; Volume 14, Issue 1-2 , 2013 , Pages 265-276 ; 16134982 (ISSN) ; Saidi, M. S ; Sadeghi, A ; Sani, M
2013
Abstract
Dielectrophoresis (DEP) is an electrokinetic phenomenon which is used for manipulating micro- and nanoparticles in micron-sized devices with high sensitivity. In recent years, electrode-based DEP by patterning narrow oblique electrodes in microchannels has been used for particle manipulation. In this theoretic study, a microchannel with triangular electrodes is presented and a detailed comparison with oblique electrodes is made. For each shape, the behavior of particles is compared for three different configurations of applied voltages. Electric field, resultant DEP force, and particle trajectories for configurations are computed by means of Rayan native code. The separation efficiency of...
An investigation of the geometrical effects on the thermal conductivity of graphene antidot lattices
, Article ECS Transactions, 2 May 2011 through 4 May 2011, Montreal, QC ; Volume 35, Issue 3 , May , 2011 , Pages 185-192 ; 19385862 (ISSN) ; 9781566778640 (ISBN) ; Pourfath, M ; Faez, R ; Kosina, H ; Sharif University of Technology
2011
Abstract
In this work we investigate the thermal conductivity of graphene-based antidot lattices. A third nearest-neighbor tight-binding model and a forth nearest-neighbor force constant model are employed to study the electronic and phononic band structures of graphene-based antidot lattices. Ballistic transport models are used to evaluate the electronic and the thermal conductivities. Methods to reduce the thermal conductivity and to increase the thermoelectric figure of merit of such structures are studied. Our results indicate that triangular antidot lattices have the smallest thermal conductivity due to longer boundaries and the smallest distance between the neighboring dots
Experimental study of parameters affecting the nusselt number of generator rotor and stator
, Article Heat Transfer Engineering ; Volume 31, Issue 3 , 2010 , Pages 243-249 ; 01457632 (ISSN) ; Nili Ahmadabadi, M ; Hashemi, A ; Sharif University of Technology
2010
Abstract
In this research, the parameters affecting the Nusselt number of a generator rotor and stator under varying heat transfer rate are experimentally studied. In spite of the stator having no grooves, the rotor has four large triangular grooves. The temperature and then heat transfer rate of the rotor and stator are experimentally measured in three longitudinal and two angular positions. First, the effect of axial Reynolds number and rotor rotational speed on the rotor and stator Nusselt number with constant heat transfer rate ratio is studied. The range of the axial Reynolds number and rotational speed used is from 4000 to 30,000 and from 300 to 1500 rpm, respectively. Next, the effect of...
Comparing calculation methods of storey stiffness to control provision of soft storey in seismic codes
, Article Earthquake and Structures ; Volume 11, Issue 1 , 2016 , Pages 1-23 ; 20927614 (ISSN) ; Noorifard, A ; Sharif University of Technology
Techno Press
2016
Abstract
Numerous buildings have been damaged or destroyed in previous earthquakes by developing soft storey. Almost all the seismic codes have provisions to prevent soft storey in structures, most of them have recommended the ratio of stiffness between adjacent storeys, but none of them has proposed the method to calculate the storey stiffness. On the other hand a great number of previous researches on stiffness have been focused on approximate methods and accurate methods by using analytical softwares have been almost neglected. In this study, six accurate methods for calculating the storey stiffness have been studied on 246 two-bay reinforced concrete frames. It is shown with the results of the...
Optomechanical coupling strength in various triangular phoxonic crystal slab cavities
, Article Journal of the Optical Society of America B: Optical Physics ; Volume 35, Issue 6 , 2018 , Pages 1390-1396 ; 07403224 (ISSN) ; Khorasani, S ; Sharif University of Technology
OSA - The Optical Society
2018
Abstract
Enhancement of interaction between optical and mechanical fields is one of the main goals of cavity optomechanics as a newly founded physics context. If the coupling rate between these fields exceeds their decay rates from the cavity, then preparation of quantum entangled states between photons of the electromagnetic field and phonons of the mechanical field becomes feasible. Among different types of cavities, phoxonic crystal (PxC) cavities have attracted attention in recent years because they can confine optical and mechanical fields simultaneously. In this paper, we introduce four PxC slabs which exhibit simultaneous photonic and phononic bandgaps. All of these crystals have a triangular...
Design and test of an astigmatism compensated dynamical stable ring resonator for a subjoule class Nd:YAG laser without external elements
, Article Optical Engineering ; Volume 58, Issue 2 , 2019 ; 00913286 (ISSN) ; Rezanejad, M ; Shayganmanesh, M ; Gohari, N ; Sharif University of Technology
SPIE
2019
Abstract
An astigmatism compensated isosceles triangular ring resonator is designed and tested for a subjoule class Nd:YAG laser, considering the thermal lensing effects. The ABCD approach is used and the laser rod is considered as a lens like media whose optical power is induced by dissipated heat in the rod. The beam spot size, divergence angle, and some other parameters were studied for both sagittal and tangential planes and a minimal astigmatic configuration is designed applying dynamic stability condition. It is shown practically that the designed resonator emits a circular TEM00 Gaussian beam (using an aperture). Comparative studies were also done considering a linear resonator especially for...
Experimental examination of utilizing novel radially grooved surfaces in the evaporator of a thermosyphon heat pipe
, Article Applied Thermal Engineering ; Volume 169 , 2020 ; Faegh, M ; Shafii, M. B ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
The application of heat pipes with flat evaporators in cooling electronic devices has attracted a lot of attention in recent years. Increasing the rate of heat transfer in their evaporator by utilizing structured surfaces is considered as a prominent method for reducing the thermal resistance of the heat pipes. In this study, the performance of a thermosyphon heat pipe with novel radially rectangular-grooved and radially inclined triangular-grooved evaporator surfaces was evaluated experimentally. It is hypothesized that the radial grooves may enhance the performance by inducing rotational motions and increasing the heat transfer coefficients. Based on the results, the optimum filling ratio...
Application of Graph Theory and Matrices of Relations in Modeling Complex Systems
, M.Sc. Thesis Sharif University of Technology ; Malaek, Mohammad Bagher (Supervisor)
Abstract
Design of complex systems requires different challenges to be met simultaneously. Yet the current methods lack a sound theoretic framework and thus designers normally rely on heuristic or empirical methods; based on available experiences. Such approaches to the system design entail both technical and business risks and subsequently increase the probability of long-term problems. In this research, along with the theoretical framework of the systems design concepts, we discuss number of important models. The main concentration of the work, however, is to; somehow, correlate Axiomatic Design Matrix (ADM) with Design Structure Matrix (DSM). Here we exploit mathematical model based on sets and by...