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A Bi-Level framework for expansion planning in active power distribution networks
, Article IEEE Transactions on Power Systems ; 2021 ; 08858950 (ISSN) ; Fotuhi Firuzabad, M ; Moeini Aghtaie, M ; Pourghaderi, N ; Dehghanian, P ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
This paper presents a new framework for multistage expansion planning in active power distribution networks, in which the distribution system operator (DSO) considers active network management by clearing the local energy market at the distribution level. The proposed model is formulated as a bi-level optimization problem, where the upper level minimizes the net present value of the total costs imposed to DSO associated with the investment and maintenance of the network assets as well as the network operation, while the lower level on clearing the local energy market captures the participation of distributed energy resource (DER) owners and demand aggregators to maximize the social welfare....
A quantization noise robust object's shape prediction algorithm
, Article 13th European Signal Processing Conference, EUSIPCO 2005, Antalya, 4 September 2005 through 8 September 2005 ; 2005 , Pages 1770-1773 ; 1604238216 (ISBN); 9781604238211 (ISBN) ; Rabiee, H. R ; Asadi, M ; Nosrati, M ; Amiri, M ; Ghanbari, M ; Sharif University of Technology
2005
Abstract
This paper introduces a quantization noise robust algorithm for object's shape prediction in a video sequence. The algorithm is based on pixel representation in the undecimated wavelet domain for tracking of the user-defined shapes contaminated by the compression noise of video sequences. In the proposed algorithm, the amplitude of coefficients in the best basis tree expansion of the undecimated wavelet packet transform is used as feature vectors (FVs). FVs robustness against quantization noise has been achieved through inherent denoising and edge component separation in the best basis selection algorithm. The algorithm uses these FVs to track the pixels of small square blocks located at the...
Harnessing power system flexibility under multiple uncertainties
, Article IET Generation, Transmission and Distribution ; Volume 16, Issue 14 , 2022 , Pages 2878-2890 ; 17518687 (ISSN) ; Saber, H ; Fattaheian Dehkordi, S ; Moeini Aghtaie, M ; Fotuhi Firuzabad, M ; Lehtonen, M ; Sharif University of Technology
John Wiley and Sons Inc
2022
Abstract
Increasing the intermittent outputs of renewable energy sources (RESs) has forced planners to define a new concept named flexibility. In this regard, some short- and long-term solutions, such as transmission expansion planning (TEP) and energy storage systems (ESSs) have been suggested to improve the flexibility amount. A proper optimization procedure is required to choose an optimal solution to improve flexibility. Therefore, a mixed-integer linear programming (MILP) direct-optimization TEP versus ESSs co-planning model is presented in this paper to enhance power system flexibility. In doing so, a novel RES-BESS-based grid-scale system flexibility metric is proposed to investigate the...
A Bi-Level framework for expansion planning in active power distribution networks
, Article IEEE Transactions on Power Systems ; Volume 37, Issue 4 , 2022 , Pages 2639-2654 ; 08858950 (ISSN) ; Fotuhi Firuzabad, M ; Moeini Aghtaie, M ; Pourghaderi, N ; Dehghanian, P ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
This paper presents a new framework for multistage expansion planning in active power distribution networks, in which the distribution system operator (DSO) considers active network management by clearing the local energy market at the distribution level. The proposed model is formulated as a bi-level optimization problem, where the upper level minimizes the net present value of the total costs imposed to DSO associated with the investment and maintenance of the network assets as well as the network operation, while the lower level on clearing the local energy market captures the participation of distributed energy resource (DER) owners and demand aggregators to maximize the social welfare....
Robust coordinated distribution system planning considering transactive DSO's market
, Article IEEE Transactions on Power Systems ; 2022 , Pages 1-11 ; 08858950 (ISSN) ; Fotuhi Firuzabad, M ; Shahidehpour, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
In this paper, a robust distribution system expansion planning (DSP) approach is presented to supply the load growth locally and move toward nearly zero energy local distribution areas (LDAs). In the proposed approach, a distribution system operator (DSO) is responsible for secure and optimum operation of LDAs. Therefore, investors on distribution system upgrades use this approach to maximize the profit on investments by determining the installation year of new distribution feeders and energy resources, distributed energy resource (DER) placements and sizes considered by corresponding DSOs. The accurate AC power flow solution is used and mathematical methods are developed to model the DSP as...
Critical voltage, thermal buckling and frequency characteristics of a thermally affected GPL reinforced composite microdisk covered with piezoelectric actuator
, Article Mechanics Based Design of Structures and Machines ; Volume 50, Issue 4 , 2022 , Pages 1331-1353 ; 15397734 (ISSN) ; Ghabussi, A ; Forooghi, A ; Shavalipour, A ; Habibi, M ; won Jung, D ; Safa, M ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
Due to the remarkable progress in the field of the manufacturing process, smart composites have become the desired target for high-tech engineering applications. Accordingly, for the first time, thermal buckling, critical voltage and vibration response of a thermally affected graphene nanoplatelet reinforced composite (GPLRC) microdisk in the thermal environment are explored with the aid of generalized differential quadrature method (GDQM). Also, the current microstructure is coupled with a piezoelectric actuator (PIAC). The extended form of Halpin-Tsai micromechanics is used to acquire the elasticity of the structure, whereas, the variation of thermal expansion, Poisson’s ratio, and density...
Drop profile analysis tensiometry under highly dynamic conditions
, Article Colloids and Surfaces A: Physicochemical and Engineering Aspects ; Volume 413 , 2012 , Pages 292-297 ; 09277757 (ISSN) ; Bastani, D ; Javadi, A ; Kovalchuk, V. I ; Kovalchuk, N. M ; Makievski, A. V ; Bonaccurso, E ; Miller, R ; Sharif University of Technology
2012
Abstract
Profile analysis tensiometry (PAT) is presently the most frequently used technique for measuring surface tensions of liquids. The basis of this methodology is however an equilibrium force balance as given by the Gauss-Laplace equation. Therefore, its application under dynamic conditions, i.e. for growing drops or bubbles, is questionable. We discuss the limits of the applicability of PAT under dynamic conditions by using a growing drop configuration equipped with a high speed video camera. The systems studied are the water/air and water/hexane interface. The obtained "dynamic" drop profiles are analyzed by fitting the classical Gauss-Laplace equation. The results are additionally compared...
Comparing the performance and recovery mechanisms for steam flooding in heavy and light oil reservoirs
, Article Society of Petroleum Engineers- SPE Heavy Oil Conference ; Volume 1 , 2012 , Pages 28-36 ; 9781622761111 (ISBN) ; Ayatollahi, S ; Shabaninejad, M ; Sharif University of Technology
SPE
2012
Abstract
The concern over fossil energy shortage for the next decade leads to the extensive research activities in the area of enhanced oil recovery. Steam injection as one of well known EOR process has been used for about five decades to improve the oil production rate and recovery efficiency. Steam flooding is applied to heavy and extra-heavy oil reservoirs; however it could be used in light oil reservoirs in which water injection do not work effectively. Regardless of different performances, this method is an efficient EOR process for both heavy and light oil reservoirs. In this work, two separate numerical models were prepared to investigate steam flooding performance for the recovery of light...
Stochastic modeling of the energy supply system with uncertain fuel price - A case of emerging technologies for distributed power generation
, Article Applied Energy ; Volume 93 , 2012 , Pages 668-674 ; 03062619 (ISSN) ; Saboohi, Y ; Sharif University of Technology
2012
Abstract
A deterministic energy supply model with bottom-up structure has limited capability in handling the uncertainties. To enhance the applicability of such a model in an uncertain environment two main issues have been investigated in the present paper. First, a binomial lattice is generated based on the stochastic nature of the source of uncertainty. Second, an energy system model (ESM) has been reformulated as a multistage stochastic problem. The result of the application of the modified energy model encompasses all uncertain outcomes together and enables optimal timing of capacity expansion. The performance of the model has been demonstrated with the help of a case study. The case study has...
Performance characterization of ultrahigh speed-optically amplified spectral-phase encodedOCDMA systems with second-harmonic-generation effect in thin and thick crystal receiver structures
, Article IEEE Transactions on Communications ; Volume 59, Issue 10 , October , 2011 , Pages 2818-2831 ; 00906778 (ISSN) ; Salehi, J. A ; Sharif University of Technology
2011
Abstract
In this paper we study and evaluate the performance of a spectral-phase encoded optical CDMA (SPE-OCDMA) system using advanced receiver structures based on second harmonic generation (SHG) effect imposed in a Thick or Thin crystal. This receiver structure is employed as the nonlinear pre-processor prior to the conventional low-speed photodetector. In our performance evaluation amplified spontaneous emission (ASE) of the optical amplifiers, receiver front end thermal noise and photodetector shot noise which are effective in low power conditions, and multiple access interference (MAI) noise which is the dominant source of noise in high power conditions in any coherent OCDMA communications...
Acoustic scattering and radiation force function experienced by functionally graded cylindrical shells
, Article Journal of Mechanics ; Volume 27, Issue 2 , June , 2011 , Pages 227-243 ; 17277191 (ISSN) ; Naei, M. H ; Honarvar, F ; Rajabi, M ; Sharif University of Technology
2011
Abstract
A body insonified by a sound field is known to experience a steady force that is called the acoustic radiation force. In this paper, the method of wave function expansion is adopted to study the scattering and the radiation force function caused by a plane normal harmonic acoustic wave incident upon an arbitrarily thick-walled functionally graded cylindrical shell submerged in and filled with compressible ideal fluids. A laminate approximate model and the so-called state space formulation in conjunction with the classical transfer matrix (T-matrix) approach are employed to present an analytical solution based on the two-dimensional exact equations of elasticity. Two typical models,...
Distribution system planning considering integration of distributed generation and load curtailment options in a competitive electricity market
, Article Electrical Engineering ; Volume 93, Issue 1 , 2011 , Pages 23-32 ; 09487921 (ISSN) ; Abbaspour Tehrani Fard, A ; Poure, P ; Saadate, S ; Sharif University of Technology
Abstract
Distribution systems management is becoming an increasingly complicated issue due to the introduction of new technologies, new energy trading strategies and new deregulated environment. In the new deregulated energy market and considering the incentives coming from the technical and economical fields, it is reasonable to consider distributed generation (DG) as a viable option to solve the lacking electric power supply problem. This paper presents a mathematical distribution system planning model considering three planning options to system expansion and to meet the load growth requirements with a reasonable price as well as the system power quality problems. DG is introduced as an attractive...
Surface and interface effects on torsion of eccentrically two-phase fcc circular nanorods: Determination of the surface/interface elastic properties via an atomistic approach
, Article Journal of Applied Mechanics, Transactions ASME ; Volume 78, Issue 1 , October , 2011 , Pages 0110111-01101111 ; 00218936 (ISSN) ; Shodja, H. M ; Sharif University of Technology
2011
Abstract
The effect of surface and interface elasticity in the analysis of the Saint-Venant torsion problem of an eccentrically two-phase fcc circular nanorod is considered; description of the behavior of such a small structure via usual classical theories cease to hold. In this work, the problem is formulated in the context of the surface/interface elasticity. For a rigorous solution of the proposed problem, conformal mapping with a Laurent series expansion are employed together. The numerical results well illustrate that the torsional rigidity and stress distribution corresponding to such nanosized structural elements are significantly affected by the size. In order to employ surface and interface...
Biodegradable ionic liquids: effects of temperature, alkyl side-chain length, and anion on the thermodynamic properties and interaction energies as determined by molecular dynamics simulations coupled with ab initio calculations
, Article Industrial and Engineering Chemistry Research ; Volume 54, Issue 46 , November , 2015 , Pages 11678-11700 ; 08885885 (ISSN) ; Gholami, M. R ; Sharif University of Technology
American Chemical Society
2015
Abstract
The effects of incorporating the ester functional group (-C=OO-) into the side chain of the 1-alkyl-3-methylimidazolium cation ([C1COOCnC1im]+, n = 1, 2, 4) paired with [Br]-, [NO3]-, [BF4]-, [PF6]-, [TfO]-, and [Tf2N]- anions on the various thermodynamic properties and interaction energies of these biodegradable ionic liquids (ILs) were investigated by means of molecular dynamics (MD) simulations combined with ab initio calculations in the temperature range of 298-550 K. Excluding the simulated density, the highest values of the volumetric properties such as molar volume, isobaric expansion coefficient, and isothermal compressibility coefficient can be attributed to the largest cation...
Chitosan-gelatin sheets as scaffolds for muscle tissue engineering
, Article Artificial Cells, Nanomedicine and Biotechnology ; Volume 43, Issue 2 , Nov , 2015 , Pages 124-132 ; 21691401 (ISSN) ; Mashayekhan, S ; Nazaripouya, A ; Naji, M ; Hunkeler, D ; Rajabi Zeleti, S ; Sharifiaghdas, F ; Sharif University of Technology
Informa Healthcare
2015
Abstract
Hydrogels made of natural polymers [chitosan (CS) and gelatin (G)] have been prepared having mechanical properties similar to those of muscle tissues. In this study, the effect of polymer concentration and scaffold stiffness on the behavior of seeded muscle-derived cells (MDCs) on the CS-G hydrogel sheets has been evaluated. Both variables were found to be important in cell viability. Viability was assessed by observation of the cell morphology after 1 day as well as a 14-day MTT assay. The CS-G hydrogels were characterized using Fourier transform infrared (FTIR) analysis, which revealed evidences of strong intermolecular interactions between CS and G. Hydrogel samples with intermediate...
Critical mass flow rate through capillary tubes
, Article American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FEDSM, 1 August 2010 through 5 August 2010 ; Volume 1, Issue PARTS A, B AND C , 2010 , Pages 51-56 ; 08888116 (ISSN) ; 9780791849484 (ISBN) ; Javidmand, P ; Fluids Engineering Division ; Sharif University of Technology
Abstract
This paper presented a numerical study that predicts critical mass flow rate, pressure, vapor quality, and void fraction along a very long tube with small diameter or capillary tub under critical condition by the drift flux model. Capillary tubes are simple expansion devices and are necessary to design and optimization of refrigeration systems. Using dimensional analysis by Buckingham's π theory, some generalized correlations are proposed for prediction of flow parameters as functions of flow properties and tube sizes under various critical conditions. This study is performed under the inlet pressure in the range of 0.8 ≤ pin ≤ 1.5Mpa, subcooling temperature between 0 ≤ ΔTsub ≤10 °C. The...
A new framework for large distribution system optimal planning in a competitive electricity market
, Article 2010 IEEE International Energy Conference and Exhibition, EnergyCon 2010, 18 December 2010 through 22 December 2010 ; 2010 , Pages 1-6 ; 9781424493807 (ISBN) ; Poure, P ; Abbaspour Tehrani Fard, A ; Saadate, S ; Sharif University of Technology
Abstract
Distribution systems management is becoming an increasingly complicated issue due to the introduction of new technologies, new energy trading strategies and new deregulated environment. In the new deregulated energy market and considering the incentives coming from the technical and economical fields, it is reasonable to consider Distributed Generation (DG) as a viable option to solve the lacking electric power supply problem. This paper presents a mathematical distribution system planning model considering three planning options to system expansion and to meet the load growth requirements with a reasonable price as well as the system power quality problems. DG is introduced as an attractive...
Piezoelectric composites with periodic multi-coated inhomogeneities
, Article International Journal of Solids and Structures ; Volume 47, Issue 21 , October , 2010 , Pages 2893-2904 ; 00207683 (ISSN) ; Weng, G. J ; Kargarnovin, M. H ; Shodja, H. M ; Sharif University of Technology
Abstract
A new, robust homogenization scheme for determination of the effective properties of a periodic piezoelectric composite with general multi-coated inhomogeneities is developed. In this scheme the coating does not have to be thin, the shape and orientation of the inclusion and coatings do not have to be identical, their centers do not have to coincide, their properties do not have to remain uniform, and the microstructure can be with the 2D elliptic or the 3D ellipsoidal inclusions. The development starts from the local electromechanical equivalent inclusion principle through the introduction of the position-dependent equivalent eigenstrain and electric field. Then with a Fourier series...
A distribution network expansion planning model considering distributed generation options and techo-economical issues
, Article Energy ; Volume 35, Issue 8 , 2010 , Pages 3364-3374 ; 03605442 (ISSN) ; Ehsan, M ; Sharif University of Technology
Abstract
This paper presents a dynamic multi-objective model for distribution network expansion, considering the distributed generations as non-wire solutions. The proposed model simultaneously optimizes two objectives namely, total costs and technical constraint satisfaction by finding the optimal schemes of sizing, placement and specially the dynamics (i.e., timing) of investments on DG units and/or network reinforcements over the planning period. An efficient heuristic search method is proposed to find non-dominated solutions of the formulated problem and a fuzzy satisfying method is used to choose the final solution. The effectiveness of the proposed model and search method are assessed and...
Uncertainty analysis for seawater intrusion in fractured coastal aquifers: Effects of fracture location, aperture, density and hydrodynamic parameters
, Article Journal of Hydrology ; Volume 571 , 2019 , Pages 159-177 ; 00221694 (ISSN) ; Fahs, M ; Ataie Ashtiani, B ; Belfort, B ; Simmons, C. T ; Younes, A ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this study we use polynomial chaos expansion (PCE) to perform uncertainty analysis for seawater intrusion (SWI) in fractured coastal aquifers (FCAs) which is simulated using the coupled discrete fracture network (DFN) and variable-density flow (VDF) models. The DFN-VDF model requires detailed discontinuous analysis of the fractures. In real field applications, these characteristics are usually uncertain which may have a major effect on the predictive capability of the model. Thus, we perform global sensitivity analysis (GSA) to provide a preliminary assessment on how these uncertainties can affect the model outputs. As our conceptual model, we consider fractured configurations of the...