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Fuel consumption information: An alternative for congestion pricing?
, Article Road and Transport Research ; Vol. 23, issue. 3 , Sep , 2014 , p. 52-64 ; 10375783 ; Zarei, H ; Sharif University of Technology
2014
Abstract
People's poor perception of the amount they spend on fuel is considered to be an important reason for the low price elasticity of gasoline demand. Users' travel demand can be changed by making them more aware of the fuel costs of different routes. As a result of becoming informed about their petrol consumption cost prior to entering traffic congestion, users may take an alternative route, change their travel schedule, or decide not to travel at all. Without considering the change in the price elasticity of gasoline demand, this study estimates the effects of providing gasoline consumption information (GCI) on people's route choice behaviour, the influence of fuel price on the effectiveness...
Caspian Sea negotiation support system
, Article World Environmental and Water Resources Congress 2010: Challenges of Change - Proceedings of the World Environmental and Water Resources Congress 2010, 16 May 2010 through 20 May 2010 ; 2010 , Pages 2694-2702 ; 9780784411148 (ISBN) ; Madani, K ; Gholizadeh, S ; Sharif University of Technology
2010
Abstract
Caspian Sea is currently a subject of one of the world's most intractable disputes, involving five coastal states of Azerbaijan, Iran, Kazakhstan, Russia, and Turkmenistan. The conflict over the legal status of this multinational water body emerged after the collapse of the Soviet Union. Since then the parties have been negotiating without reaching an agreement on the ownerships of waters, and the oil and natural gas beneath them. Although different division methods have been suggested so far for sharing the Caspian Sea, the gains of the countries from sea area and valuable resources remain unclear as the proposed methods are either focused on the areal shares or on the oil and gas shares....
Rapid growth of hydroxyapatite nanoparticles using ultrasonic irradiation
, Article Ultrasonics Sonochemistry ; Volume 17, Issue 5 , Jun , 2010 , Pages 853-856 ; 13504177 (ISSN) ; Taghavinia, N ; Rouhani, S ; Sharif University of Technology
2010
Abstract
A rapid, environmental friendly and low-cost method to prepare hydroxyapatite nanoparticles is proposed. In this method, hydroxyapatite is produced in a sonicated pseudo-body solution. The sonication time was found effective in the formation of the crystalline phase of nanoparticles. In our experimental condition, 15 min sonication resulted in the most pure hydroxyapatite phase. Also it was shown that growth temperature is a crucial factor and hydroxyapatite crystallizes only at 37 °C. The particles formed by sonication were generally smaller and more spherical than those obtained without sonication. Sonication increased the hydroxyapatite crystal growth rate up to 5.5 times compared to...
Observation of a crossover in kinetic aggregation of Palladium colloids
, Article Applied Surface Science ; Volume 353 , 2015 , Pages 1143-1149 ; 01694332 (ISSN) ; Ranjbar, M ; Rouhani, S ; Sharif University of Technology
Elsevier
2015
Abstract
We use field emission scanning electron microscope (FE-SEM) to investigate the growth of palladium colloids over the surface of thin films of WO3 /glass. The film is prepared by Pulsed Laser Deposition (PLD) at different temperatures. A PdCl2 (aq) droplet is injected on the surface and in the presence of steam hydrogen the droplet is dried through a reduction reaction process. Two distinct aggregation regimes of palladium colloids are observed over the substrates. We argue that the change in aggregation dynamics emerges when the measured water drop Contact Angel (CA) for the WO3 /glass thin films passes a certain threshold value, namely CA ≈ 46°, where a...
A note on an inequality between energy and sombor index of a graph
, Article Match ; Volume 90, Issue 3 , 2023 , Pages 765-771 ; 03406253 (ISSN) ; Habibi, M ; Rouhani, S ; Sharif University of Technology
University of Kragujevac, Faculty of Science
2023
Abstract
The Sombor index of graph G is defined as Σuv∈E(G) √d2u + d2v, where du and dv are the degree of vertices u and v in G, respectively. The energy of G is defined as the sum of absolute values of all eigenvalues of its adjacency matrix and denoted by ε(G). It was proved that if G is a graph of order at least 3, then ε(G) < SO(G). In this paper, we strengthen this result by showing that if G is a connected graph of order n which is not Pn(n ≤ 8), then ε(G) ≤ SO(G)/2. © 2023 University of Kragujevac, Faculty of Science. All rights reserved
First-passage-time processes and subordinated Schramm-Loewner evolution
, Article Physical Review E - Statistical, Nonlinear, and Soft Matter Physics ; Volume 84, Issue 1 , July , 2011 ; 15393755 (ISSN) ; Rajabpour, M. A ; Rouhani, S ; Sharif University of Technology
2011
Abstract
We study the first-passage-time processes of the anomalous diffusion on the self-similar curves in two dimensions. The scaling properties of the mean-square displacement and mean first passage time of the fractional Brownian motion and subordinated walk on the different fractal curves (loop-erased random walk, harmonic explorer, and percolation front) are derived. We also define natural parametrized subordinated Schramm-Loewner evolution (NS-SLE) as a mathematical tool that can model diffusion on fractal curves. The scaling properties of the mean-square displacement and mean first passage time for NS-SLE are obtained by numerical means
Generating Bell states in invariant stratification spin networks
, Article Journal of Statistical Mechanics: Theory and Experiment ; Volume 2010, Issue 12 , 2010 ; 17425468 (ISSN) ; Jafarizadeh, M. A ; Rouhani, S ; Sharif University of Technology
2010
Abstract
In this paper, we study the generation of Bell states between distant vertices in a permanently coupled quantum spin network, interacting via invariant stratification graphs. To begin with we establish a class of upper bounds over the achievable entanglement between the reference site and various vertices. We observe that the maximum of these upper bounds is one e-bit. We conclude that the reference site can generate a Bell state with a vertex if the corresponding upper bound of the vertex is one e-bit. Thus for generation of a Bell state this upper bound must be saturated. Taking this into account, we obtain the characteristic constraint of the proper graphs. We introduce a special class of...
The provision of optimal entanglement on underlying networks of group association schemes
, Article Journal of Statistical Mechanics: Theory and Experiment ; Volume 2010, Issue 3 , 2010 ; 17425468 (ISSN) ; Jafarizadeh, M. A ; Rouhani, S ; Sharif University of Technology
2010
Abstract
We investigate the creation of optimal entanglement in axially symmetric networks. The proposed network is one in which the connections are organized using a group table - in other words, using group association schemes. We show that optimal entanglement can be provided on such networks by adjusting couplings and the initial state. We find that the optimal initial state is a simple locally excited state. Moreover we obtain an analytic formula for the entanglement achievable between vertex pairs located in the same or conjugate strata and calculate their relevant optimal couplings. For those pairs located in non-conjugate strata, two upper bounds are presented. These results are also checked...
Observation of SLE(K,P) on the critical statistical models
, Article Journal of Physics A: Mathematical and Theoretical ; Volume 45, Issue 9 , February , 2012 ; 17518113 (ISSN) ; Moghimi Araghi, S ; Rouhani, S ; Sharif University of Technology
2012
Abstract
Schramm-Loewner evolution (SLE) is a stochastic process that helps classify critical statistical models using one real parameter K. Numerical study of SLE often involves curves that start and end on the real axis. To reduce numerical errors in studying the critical curves which start from the real axis and end on it, we have used hydrodynamically normalized SLE(K,P) which is a stochastic differential equation governing such curves. In this paper, we directly verify this hypothesis and numerically apply this formalism to the domain wall curves of the Abelian sandpile model (K= 2) and critical percolation (K= 6). We observe that this method is more reliable than previously used methods in the...
Avalanche frontiers in the dissipative Abelian sandpile model and off-critical Schramm-Loewner evolution
, Article Physical Review E - Statistical, Nonlinear, and Soft Matter Physics ; Volume 85, Issue 5 , 2012 ; 15393755 (ISSN) ; Moghimi Araghi, S ; Rouhani, S ; Sharif University of Technology
2012
Abstract
Avalanche frontiers in Abelian sandpile model (ASM) are random simple curves whose continuum limit is known to be a Schramm-Loewner evolution with diffusivity parameter κ=2. In this paper we consider the dissipative ASM and study the statistics of the avalanche and wave frontiers for various rates of dissipation. We examine the scaling behavior of a number of functions, such as the correlation length, the exponent of distribution function of loop lengths, and the gyration radius defined for waves and avalanches. We find that they do scale with the rate of dissipation. Two significant length scales are observed. For length scales much smaller than the correlation length, these curves show...
Conformal curves on the WO3 surface
, Article Physical Review Letters ; Volume 100, Issue 4 , 2008 ; 00319007 (ISSN) ; Rajabpour, M. A ; Rouhani, S ; Sharif University of Technology
2008
Abstract
We have studied the isoheight lines on the WO3 surface as a physical candidate for conformally invariant curves. We have shown that these lines are conformally invariant with the same statistics of domain walls in the critical Ising model. They belong to the family of conformal invariant curves called Schramm-Loewner evolution (or SLEκ), with diffusivity of κ∼3. This can be regarded as the first experimental observation of SLE curves. We have also argued that Ballistic Deposition (BD) can serve as a growth model giving rise to contours with similar statistics at large scales. © 2008 The American Physical Society
Simulation of DNA electrophoresis through microstructures
, Article Electrophoresis ; Volume 28, Issue 3 , 2007 , Pages 301-308 ; 01730835 (ISSN) ; Sarbolouki, M. N ; Rouhani, S ; Sharif University of Technology
2007
Abstract
The dependence of the mobility of DNA molecules through an hexagonal array of micropillars on their length and the applied electric field was investigated and it was found that mobility is a nonmonotonic function of their length. Results also revealed that the size dependence of the DNA mobility depends on the applied electric field and there is a crossover around E ≈ 25 V/cm for the mobility of λ-DNA and T4-DNA. These observations are explained in terms of the diffusion process inside the structure affected by the solvent and are modeled using the Langevin and its corresponding Fokker-Planck equations. The phenomenon is generalized under three regimes in a phase diagram relating the...
SLE(κ,ρ) and boundary Coulomb gas
, Article Nuclear Physics B ; Volume 740, Issue 3 , 2006 , Pages 348-357 ; 05503213 (ISSN) ; Rajabpour, M. A ; Rouhani, S ; Sharif University of Technology
2006
Abstract
We consider the Coulomb gas model on the upper half-plane with different boundary conditions, namely, Dirichlet, Neumann and mixed. We relate this model to SLE(κ, ρ) theories. We derive a set of conditions connecting the total charge of the Coulomb gas, the boundary charges, the parameters κ and ρ. Also we study a free fermion theory in presence of a boundary and show with the same methods that it would lead to logarithmic boundary changing operators. © Elsevier B.V. All rights reserved
Abelian sandpile model: A conformal field theory point of view
, Article Nuclear Physics B ; Volume 718, Issue 3 , 2005 , Pages 362-370 ; 05503213 (ISSN) ; Rajabpour, M. A ; Rouhani, S ; Sharif University of Technology
2005
Abstract
In this paper we derive the scaling fields in c = -2 conformal field theory associated with weakly allowed clusters in Abelian sandpile model and show a direct relation between the two models. © 2005 Elsevier B.V. All rights reserved
Logarithmic conformal null vectors and SLE
, Article Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics ; Volume 600, Issue 3-4 , 2004 , Pages 297-301 ; 03702693 (ISSN) ; Rajabpour, M. A ; Rouhani, S ; Sharif University of Technology
2004
Abstract
Formal Loewner evolution is connected to conformal field theory. In this Letter we introduce an extension of Loewner evolution, which consists of two coupled equations and connect the martingales of these equations to the null vectors of logarithmic conformal field theory. © 2004 Elsevier B.V. All rights reserved
Statistical physics of complex fluids
, Article Journal of Physics Condensed Matter ; Volume 17, Issue 14 , 2005 , Pages i-iii ; 09538984 (ISSN) ; Khajehpour, M. R. H ; Kolahchi, M. R ; Rouhani, S ; Sharif University of Technology
Institute of Physics Publishing
2005
Demythifying the belief in cryptocurrencies decentralized aspects. A study of cryptocurrencies time cross-correlations with common currencies, commodities and financial indices
, Article Physica A: Statistical Mechanics and its Applications ; Volume 556 , October , 2020 ; Jafari, G ; Rouhani, S ; Ausloos, M ; Sharif University of Technology
Elsevier B. V
2020
Abstract
The main question of this article is about whether cryptocurrencies, within their decentralization aspects, are a real commodity or/and a virtual currency. To resolve such a dilemma, we compare 7 cryptocurrencies with a sample of the three types of monetary systems: 28 fiat money, 2 commodities, 2 commodity based indices, and 3 financial market indices. We use the matrix correlation method. We display dendrograms and observe “hierarchy clustering”, as a function of data coarse graining. In fact, we confirm that the cryptocurrencies are not decentralized. We observe also that most of the currencies in the world are not significantly correlated or present a weak correlation with...
Optimizing temperature and introducing new process arrangements for elevating clay's longevity based on the known poisons in the separation process of trace olefins from aromatics
, Article Journal of Chemical Technology and Biotechnology ; 2021 ; 02682575 (ISSN) ; Farhadi, F ; Akbari Kenari, M ; Ramakrishna, S ; Sharif University of Technology
John Wiley and Sons Ltd
2021
Abstract
BACKGROUND: The clay treatment widely utilized to reduce unsaturated components in aromatic stream has a detrimental effect on catalyst lifetime. Due to the short lifetime of commercial clay, a huge number of studies have been carried out to address this problem over the last decade. This study aims to optimize the temperature for longer serviceability of clay by removal of unsaturated aliphatic components from aromatic streams through the adsorption and catalytic properties of clay. A novel process arrangement is introduced by scheduling the reuse of deactivated clay that is discarded after deactivation. RESULTS: Results showed that the suitable range of temperature for olefin removal is...
Optimizing temperature and introducing new process arrangements for elevating clay's longevity based on the known poisons in the separation process of trace olefins from aromatics
, Article Journal of Chemical Technology and Biotechnology ; Volume 97, Issue 4 , 2022 , Pages 973-983 ; 02682575 (ISSN) ; Farhadi, F ; Akbari Kenari, M ; Ramakrishna, S ; Sharif University of Technology
John Wiley and Sons Ltd
2022
Abstract
BACKGROUND: The clay treatment widely utilized to reduce unsaturated components in aromatic stream has a detrimental effect on catalyst lifetime. Due to the short lifetime of commercial clay, a huge number of studies have been carried out to address this problem over the last decade. This study aims to optimize the temperature for longer serviceability of clay by removal of unsaturated aliphatic components from aromatic streams through the adsorption and catalytic properties of clay. A novel process arrangement is introduced by scheduling the reuse of deactivated clay that is discarded after deactivation. RESULTS: Results showed that the suitable range of temperature for olefin removal is...
Some relations between rank, vertex cover number and energy of graph
, Article Match ; Volume 89, Issue 3 , 2023 , Pages 653-664 ; 03406253 (ISSN) ; Alizadeh, H ; Fakharan, M ; Habibi, M ; Rabizadeh, S ; Rouhani, S ; Sharif University of Technology
University of Kragujevac, Faculty of Science
2023
Abstract
In this paper, we extend some results of [F. Shaveisi, lower bounds on the vertex cover number and energy of graphs, MATCH Commun. Math. Comput. Chem, 87(3) (2022) 683-692] which state some relations between the vertex cover and other parameters, such as the order and maximum or minimum degree of graphs. Also, we prove that for a graph G, E(G) ≥ 2β(G) - 2Ce(G) and so E(G) ≥ 2β(G) - 2C(G), where E(G), β(G), Ce(G) and C(G) denote the energy, vertex cover, number of even cycles and number of cycles in G, respectively. For these both inequalities we investigate their equality. Finally, we give some relations between E(G), γ(G) and γt(G), where γ(G) and γt(G) are domination number and total...