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Dynamic economic evaluation of distribution automation systems
, Article 2009 International Conference on Electric Power and Energy Conversion Systems, EPECS 2009 ; 2009 ; 9789948427155 (ISBN) ; Ehsan, M ; Sharif University of Technology
2009
Abstract
In a deregulated environment of power distribution industry, a comprehensive economic evaluation for the implementation of distribution automation (DA) systems is inevitable. Using the presented methodology in this paper and system dynamics approach, it is efficiently possible to deal with variation of the economic parameters such as the interest rate, inflation rate, energy supply cost, load growth, etc. In this paper, economic short-run and long-run impacts of DA systems are evaluated from utility point of view. Also economic benefits from customers' point of view are analyzed. A practical pricing strategy for maximizing the utility profit is suggested depending on the underlying market...
Some clarifications on the relation between bohmian quantum potential and mach’s principle
, Article International Journal of Theoretical Physics ; Volume 56, Issue 10 , 2017 , Pages 3096-3107 ; 00207748 (ISSN) ; Golshani, M ; Sharif University of Technology
2017
Abstract
Mach’s principle asserts that the inertial mass of a body is related to the distribution of other distant bodies. This means that in the absence of other bodies, a single body has no mass. In this case, talking about motion is not possible, because the detection of motion is possible only relative to other bodies. But in physics we are faced with situations that are not fully Machian. As in the case of general theory of relativity where geodesics exist in the absence of any matter, the motion has meaning. Another example which is the main topic of our discussion, refers to Bohmian quantum mechanics, where the inertial mass of a single particle does not vanish, but is modified. We can call...
Some clarifications about the bohmian geodesic deviation equation and raychaudhuri's equation
, Article International Journal of Modern Physics A ; Volume 33, Issue 3 , 2018 ; 0217751X (ISSN) ; Golshani, M ; Sharif University of Technology
World Scientific Publishing Co. Pte Ltd
2018
Abstract
One of the important and famous topics in general theory of relativity and gravitation is the problem of geodesic deviation and its related singularity theorems. An interesting subject is the investigation of these concepts when quantum effects are considered. Since the definition of trajectory is not possible in the framework of standard quantum mechanics (SQM), we investigate the problem of geodesic equation and its related topics in the framework of Bohmian quantum mechanics in which the definition of trajectory is possible. We do this in a fixed background and we do not consider the backreaction effects of matter on the space-time metric. © 2018 World Scientific Publishing Company
On the dynamics of gravity-induced wave function reduction
, Article International Journal of Modern Physics A ; Volume 36, Issue 26 , 2021 ; 0217751X (ISSN) ; Golshani, M ; Sharif University of Technology
World Scientific
2021
Abstract
In this study, we use the concept of Bohmian trajectories to present a dynamical and deterministic interpretation for the gravity-induced wave function reduction. We shall classify all possible regimes for the motion of a particle, based on the behavior of trajectories in the ensemble and under the influence of quantum and gravitational forces. In the usual approaches all the information is obtained from the wave function evolution. But, on the basis of Bohm's deterministic quantum theory, we can investigate the motion of the particle during the reduction processes. This leads to analytical and numerical results for the reduction time and equation of motion of the particle. In this regard, a...
A Bohmian approach to the perturbations of non-linear Klein-Gordon equation
, Article Pramana - Journal of Physics ; Volume 87, Issue 2 , 2016 ; 03044289 (ISSN) ; Golshani, M ; Sarbishei, M ; Sharif University of Technology
Indian Academy of Sciences
2016
Abstract
In the framework of Bohmian quantum mechanics, the Klein-Gordon equation can be seen as representing a particle with mass m which is guided by a guiding wave φ(x) in a causal manner. Here a relevant question is whether Bohmian quantum mechanics is applicable to a non-linear Klein-Gordon equation? We examine this approach for φ4(x) and sine-Gordon potentials. It turns out that this method leads to equations for quantum states which are identical to those derived by field theoretical methods used for quantum solitons. Moreover, the quantum force exerted on the particle can be determined. This method can be used for other non-linear potentials as well
Deriving relativistic Bohmian quantum potential using variational method and conformal transformations
, Article Pramana - Journal of Physics ; Volume 86, Issue 4 , 2016 , Pages 747-761 ; 03044289 (ISSN) ; Golshani, M ; Sarbishei, M ; Sharif University of Technology
2016
Abstract
In this paper we shall argue that conformal transformations give some new aspects to a metric and changes the physics that arises from the classical metric. It is equivalent to adding a new potential to relativistic Hamilton-Jacobi equation. We start by using conformal transformations on a metric and obtain modified geodesics. Then, we try to show that extra terms in the modified geodesics are indications of a background force. We obtain this potential by using variational method. Then, we see that this background potential is the same as the Bohmian non-local quantum potential. This approach gives a method stronger than Bohm's original method in deriving Bohmian quantum potential. We do not...
Robust and rapid converging adaptive beamforming via a subspace method for the signal-plusinterferences covariance matrix estimation
, Article IET Signal Processing ; Vol. 8, Issue. 5 , July , 2014 , pp. 507-520 ; ISSN: 17519675 ; Bastani, M. H ; Sharif University of Technology
2014
Abstract
The presence of the desired signal (DS) in the training snapshots makes the adaptive beamformer sensitive to any steering vector mismatch and dramatically reduces the convergence rate. Even the performance of the most of the existing robust adaptive beamformers is degraded when the signal-to-noise ratio (SNR) is increased. In this study, a high converging rate robust adaptive beamformer is proposed. This method is a promoted eigenspace-based beamformer. In this paper, a new signal-plus-interferences (SPI) covariance matrix estimator is proposed. The subspace of the ideal SPI covariance matrices is exploited and the estimated covariance matrix is projected into this subspace. This projection...
Quantifying the impacts of agricultural alteration and climate change on the water cycle dynamics in a headwater catchment of Lake Urmia Basin
, Article Agricultural Water Management ; Volume 270 , 2022 ; 03783774 (ISSN) ; Danesh Yazdi, M ; Sharif University of Technology
Elsevier B.V
2022
Abstract
The rapid shrinkage of Lake Urmia over the past two decades has raised serious environmental concerns. Several restoration plans have been proposed to reduce agricultural water consumption to supply a remarkable fraction of the lake's environmental flow requirement. However, an accurate and realistic evaluation of the effectiveness of these plans in reducing agricultural water consumption across the basin is still poorly understood. This study assessed the water-saving potential of agricultural alteration in a snow-dominated catchment in the Lake Urmia Basin. In particular, we explored the impact of crop pattern alteration via reducing the cultivation area and employing different irrigation...
Alternative solution for kinematic interaction problem of soil-structure systems with embedded foundation
, Article Structural Design of Tall and Special Buildings ; Volume 22, Issue 3 , 2013 , Pages 251-266 ; 15417794 (ISSN) ; Ghannad, M. A ; Rahmani, M. T ; Sharif University of Technology
2013
Abstract
An effective procedure to incorporate kinematic interaction (KI) aspects in seismic analysis of soil-structures systems was presented. In this regard, first, the effect of KI on the structural response was investigated with special focus on the role of rocking component of foundation input motion (FIM). This was performed parametrically for a wide range of selected nondimensional parameters, which well define the introduced simplified soil-structure model. It was observed that ignoring the effect of rocking input motion may introduce errors, which can be on the unsafe side especially for slender structures with large embedment ratios. On the other hand, it was known that introducing the...
Improving the readability and saliency of abstractive text summarization using combination of deep neural networks equipped with auxiliary attention mechanism
, Article Journal of Supercomputing ; Volume 78, Issue 2 , 2022 , Pages 2528-2555 ; 09208542 (ISSN) ; Manzuri, M. T ; Rahmani, A. M ; Sharif University of Technology
Springer
2022
Abstract
Rapid and exponential development of textual data in recent years has yielded to the need for automatic text summarization models which aim to automatically condense a piece of text into a shorter version. Although various unsupervised and machine learning-based approaches have been introduced for text summarization during the last decades, the emergence of deep learning has made remarkable progress in this field. However, deep learning-based text summarization models are still in their early steps of development and their potential has yet to be fully explored. Accordingly, a novel abstractive summarization model is proposed in this paper which utilized the combination of convolutional...
Electron beam induced modifications in crystalline structure of polyvinylidene fluoride/nanoclay composites
, Article Radiation Measurements ; Vol. 60 , January , 2014 , pp. 1-6 ; ISSN: 13504487 ; Dadbin, S ; Frounchi, M ; Sharif University of Technology
2014
Abstract
PVDF/nanoclay nanocomposites were prepared via melt mixing method. The intercalated dispersion of the nanoclay in PVDF matrix was confirmed by XRD. According to FTIR, DSC and XRD results, the presence of nanoclay facilitated transition from α-to-β crystalline phase. Electron beam irradiation decreased the melting point of the nanocomposites. The decrease in melting point of the nanocomposites was about 11 C at 500 kGy. The crystallinity of nanocomposites increased at an irradiation dose of 100 kGy and decreased at higher irradiation doses. The extent of crosslinking of the nanocomposites increased significantly with irradiation up to 300 kGy. The nanoclay intensified the increase in yield...
Characterization of PVDF/Nanoclay Nanocomposites Prepared by Melt, Solution, and Co-Precipitation Methods
, Article International Journal of Polymer Analysis and Characterization ; Volume 17, Issue 4 , 2012 , Pages 291-301 ; 1023666X (ISSN) ; Dadbin, S ; Frounchi, M ; Sharif University of Technology
2012
Abstract
Poly (vinylidene fluoride) (PVDF) nanocomposites were prepared via melt, solution, and co-precipitation mixing methods using Cloisite 30B as organoclay. The results from X-ray diffraction patterns display intercalation or exfoliation of nanoclay depending on the nanocomposite preparation method. The solvent cast and co-precipitated samples showed exfoliation, while intercalation was observed in the nanocomposites prepared by melt mixing. Introducing organoclay induced formation of β-crystals in the PVDF nanocomposites as evidenced by XRD and FT-IR. FT-IR analysis indicated that the samples prepared by the co-precipitation method had a higher tendency for β phase formation, while the sample...
An adaptive approach for PEVs charging management and reconfiguration of electrical distribution system penetrated by renewables
, Article IEEE Transactions on Industrial Informatics ; 2017 ; 15513203 (ISSN) ; Fotuhi Firuzabad, M ; Sharif University of Technology
2017
Abstract
An adaptive approach for distribution system reconfiguration and charging management of plug-in electric vehicles (PEV) is presented in this study. A stochastic model predictive control is applied to stochastically, adaptively, and dynamically reconfigure the system, manage the incidental charging pattern of PEVs, and deal with the variable and uncertain power of renewable energy sources. The objective function of problem is minimizing daily operation cost of system. Herein, the geography of area is considered and the behavior of PEVs' drivers (based on their income level) is modeled with respect to the value of incentive and their hourly distance from each charging station. It is shown that...
An adaptive approach for PEVs charging management and reconfiguration of electrical distribution system penetrated by renewables
, Article IEEE Transactions on Industrial Informatics ; Volume 14, Issue 5 , May , 2018 , Pages 2001-2010 ; 15513203 (ISSN) ; Fotuhi Firuzabad, M ; Sharif University of Technology
IEEE Computer Society
2018
Abstract
An adaptive approach for distribution system reconfiguration and charging management of plug-in electric vehicles (PEV) is presented in this study. A stochastic model predictive control is applied to stochastically, adaptively, and dynamically reconfigure the system, manage the incidental charging pattern of PEVs, and deal with the variable and uncertain power of renewable energy sources. The objective function of problem is minimizing daily operation cost of system. Herein, the geography of area is considered and the behavior of PEVs' drivers (based on their income level) is modeled with respect to the value of incentive and their hourly distance from each charging station. It is shown that...
Gravitational reduction of the wave function based on bohmian quantum potential
, Article International Journal of Modern Physics A ; Volume 33, Issue 22 , 2018 ; 0217751X (ISSN) ; Golshani, M ; Jafari, G ; Sharif University of Technology
2018
Abstract
In objective gravitational reduction of the wave function of a quantum system, the classical limit of the system is obtained in terms of the objective properties of the system. On the other hand, in Bohmian quantum mechanics the usual criterion for getting classical limit is the vanishing of the quantum potential or the quantum force of the system, which suffers from the lack of an objective description. In this regard, we investigated the usual criterion of getting the classical limit of a free particle in Bohmian quantum mechanics. Then we argued how it is possible to have an objective gravitational classical limit related to the Bohmian mechanical concepts like quantum potential or...
A geometric look at the objective gravitational wave function reduction
, Article Pramana - Journal of Physics ; Volume 94, Issue 1 , 2020 ; Golshani, M ; Jafari, G ; Sharif University of Technology
Springer
2020
Abstract
There is a famous criterion for objective wave function reduction which is derived by using the Shrödinger–Newton equation [L Diosi, Phys. Lett. A105(4–5), 199 (1984)]. In this regard, a critical mass for the transition from quantum world to the classical world is determined for a particle or an object. In this paper, we shall derive that criterion by using the concept of Bohmian trajectories. This study has two consequences. The first is, it provides a geometric framework for the problem of wave function reduction. The second is, it represents the role of quantum and gravitational forces in the reduction process. © 2020, Indian Academy of Sciences
Analysis of the effect of kevlar fibers on abrasion resistance, flexural strength and hydraulic conductivity coefficient of silica fume concretes
, Article Iranian Journal of Science and Technology - Transactions of Civil Engineering ; Volume 44, Issue 2 , 2020 , Pages 669-674 ; Piroti, S ; Ghameian, M ; Sharif University of Technology
Springer
2020
Abstract
Reinforcing fiber and silica fume of concrete can be considered as one of the most widely used additives. In this study, with a review of the history and advantages of using silica fume and polypropylene fibers in concrete, 380 concrete laboratory samples were constructed, of which 25 mixing designs with water–cement ratio of 0.35 and fiber content of 0.2, 0.3, 0.4 and 0.5 of concrete volume and 7% silica fume were prepared according to the ACI standard in their manufacturing. In the present research, samples of Kevlar fiber containing silica fume were tested under flexural strength, abrasion resistance and hydraulic conductivity coefficient. According to achieved results, the optimum amount...
Biodiesel production from sunflower oil using k2co3 impregnated kaolin novel solid base catalyst
, Article JAOCS, Journal of the American Oil Chemists' Society ; Volume 98, Issue 6 , 2021 , Pages 633-642 ; 0003021X (ISSN) ; Kazemeini, M ; Rahmani, M. H ; Zehtab Salmasi, M ; Sharif University of Technology
John Wiley and Sons Inc
2021
Abstract
Kaolin clay material was loaded with potassium carbonate by impregnation method as a novel, effective, and economically heterogeneous catalyst for biodiesel production of sunflower oil via the transesterification reaction. The structural and chemical properties of the produced catalysts were characterized through several analyses including the X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy, and Brunauer–Emmett–Teller specific surface area. These revealed the best catalyst for the investigated reaction among different ones prepared based upon various impregnation extent of the potassium carbonate. The influence of this parameter was examined through a...
Role of EVs in the optimal operation of multicarrier energy systems
, Article Green Energy and Technology ; Volume Part F1271 , 2023 , Pages 69-117 ; 18653529 (ISSN) ; Davoudi, M ; Moeini Aghtaie, M ; Rahmani Andebili, M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2023
Abstract
Multicarrier energy systems have recently gained considerable attention as such a concept can address the mutual interrelation between energy carriers. Multicarrier energy systems aim to satisfy the different types of energy demands of a consumer while minimizing economic and environmental costs. Different energy conversion units are used in an energy hub to achieve this goal. One of the newly added components to energy hubs is electric vehicles (EVs). EVs could be regarded as a pure consumer, or a flexibility provider for the energy hub, as their batteries can be utilized to store the electricity and release it whenever needed. Therefore, EVs can help reduce the operational cost of the...
Calculation of the deterministic optimum loading pattern of the BUSHEHR VVER-1000 reactor using the weighting factor method
, Article Annals of Nuclear Energy ; Volume 49 , 2012 , Pages 170-181 ; 03064549 (ISSN) ; Pazirandeh, A ; Ghofrani, M. B ; Sadighi, M ; Sharif University of Technology
2012
Abstract
In the calculation of the optimum loading pattern for a nuclear reactor, several parameters, including the multiplication factor maximization, the raising of the desired safety threshold during the cycle length and the flattening of the radial power peaking factor should be taken into account. Our evaluation of numerous probable arrangements within the VVER-1000 reactor core (approx. 6 × 10 14 cases) indicated that a direct search of the optimum loading pattern is not feasible. Hence, in this study, the weighting factor method and some constraints on the arrangement of the fuel assemblies were applied so that the above cases were reduced to only 244 possible arrangements. Then, using a...