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A game theory approach for optimal routing: in wireless sensor networks [electronic resource]
, Article Published in: Wireless Communications Networking and Mobile Computing (WiCOM), 2010 6th International Conference on ; (2013), Vol. 3, No. 3, pp. 62-75 ; Eshghi, Kourosh ; Sharif University of Technology
Abstract
In this paper, a "Game Theory" approach for finding an optimal path in a "Wireless Sensor Network" is discussed. WSN is one of the most interesting research fields in the communication networks, and is the center of attention in recent years. In our model, a pricing and payment technique is presented to obtain an optimal path in a WSN by considering reliability, energy and traffic load. The proposed algorithm is able to find a path which improves network lifetime, load distribution and path reliability
Molecular dynamics investigation of β-SiC behavior under three-axial tensile loading [electronic resource]
, Article Journal of Computational and Theoretical Nanoscience ; November 2011, Volume 8, Number 11, PP. 2187-2192 ; Simchi, A. (Abdolreza) ; Besharati-Givi, M.K ; Rajabpour, A ; Sharif University of Technology
Abstract
Molecular dynamics (MD) simulations were used to study the mechanical behaviour of β-SiC at nano-scale under tensile loading. Effects of loading rate and tensile temperature on the mechanical properties and failure were studied. Modified embedded-atom method (MEAM) potential and Berendsen thermostat were utilized for modelling. Periodic boundary conditions were employed and the behaviour of material was analyzed under three-axial loading condition at which the stress–strain relation was acceptably size independent. It is shown that with increasing the loading rate from 5 m/s to 70 m/s, the failure strain increases without a remarkable change in the stress–strain relationship. The MD...
Numerical simulation of ductile crack growth under cyclic and dynamic loading with a damage–viscoplasticity model
, Article Engineering Fracture Mechanics ; Volume 99 , February , 2013 , PP. 169–190 ; Eghbalian, M ; Azadi, H ; Saffar, H ; Sharif University of Technology
Abstract
In this paper, the crack propagation in ductile materials is simulated under cyclic and dynamic loading. The adaptive finite element method is used to model the discontinuity due to crack propagation. The ductile fracture assumptions and continuum damage mechanics are utilized to model the material rupture behavior. Moreover both the rate-independent and rate-dependent constitutive equations are elaborated and the crack closure effect and combined hardening model are discussed in addition to some aspects of finite element implementation. Finally, a comparison is performed between the numerical simulation results and those of experiments to illustrate the robustness of proposed computational...
Home load management in a residential energy hub
, Article Electric Power Systems Research ; Vol. 119, issue , 2015 , p. 322-328 ; ISSN: 3787796 ; Fotuhi-Firuzabad, M ; Lehtonen, M ; Sharif University of Technology
Abstract
One way of more efficiently utilizing the existing gas and electrical infrastructures is to consider them as one integrated system in planning and operation of energy systems. The energy hub framework is adopted to determine a modeling procedure for such multi carrier energy systems. This paper presents a residential energy hub model for a smart home. A residential combined heat and power (CHP) as a cogeneration technology, and a plug-in hybrid electric vehicle are employed in the model. Operation of the hub is optimized through a proposed optimization-based formulation. The objective is to minimize customer payment cost. Solving the problem determines how much of each energy carrier the...
ISO's optimal strategies for scheduling the hourly demand response in day-ahead markets
, Article IEEE Transactions on Power Systems ; Vol. 29, issue. 6 , 2014 , p. 2636-2645 ; ISSN: 8858950 ; Fotuhi-Firuzabad, M ; Shahidehpour, M ; Sharif University of Technology
Abstract
This paper presents a hierarchical demand response (DR) bidding framework in the day-ahead energy markets which integrates customer DR preferences and characteristics in the ISO's market clearing process. In the proposed framework, load aggregators submit aggregated DR offers to the ISO which would centrally optimize final decisions on aggregators' DR contributions in wholesale markets. The hourly load reduction strategies include load shifting and curtailment and the use of onsite generation and energy storage systems. The ISO applies mixed-integer linear programming (MILP) to the solution of the proposed DR model in the day-ahead market clearing problem. The proposed model is implemented...
A decomposed solution to multiple-energy carriers optimal power flow
, Article IEEE Transactions on Power Systems ; Vol. 29, issue. 2 , March , 2014 , p. 707-716 ; ISSN: 8858950 ; Abbaspour, A ; Fotuhi-Firuzabad, M ; Hajipour, E ; Sharif University of Technology
Abstract
Presence of energy hubs in the future vision of energy networks creates a great opportunity for system planners and operators to move towards more efficient systems. The role of energy hubs as the intermediate in multi-carrier energy (MCE) systems calls for a generic framework to study the new upcoming technical as well as economical effects on the system performance. In response, this paper attempts to develop a general optimization and modeling framework for coupled power flow studies on different energy infrastructures. This, as a large-scale nonlinear problem, is approached through a robust optimization technique, i.e., multi-agent genetic algorithm (MAGA). The proposed procedure...
Investigating the impacts of different price-based demand response programs on home load management
, Article Journal of Electrical Engineering and Technology ; Vol. 9, issue. 3 , 2014 , p. 1125-1131 ; ISSN: 19750102 ; Fotuhi-Firuzabad, M ; Choi, J ; Sharif University of Technology
Abstract
Application of residential demand response (DR) programs are currently realized up to a limited extent due to customers' difficulty in manually responding to the time-differentiated prices. As a solution, this paper proposes an automatic home load management (HLM) framework to achieve the household minimum payment as well as meet the operational constraints to provide customer's comfort. The projected HLM method controls on/off statuses of responsive appliances and the charging/discharging periods of plug-in hybrid electric vehicle (PHEV) and battery storage at home. This paper also studies the impacts of different time-varying tariffs, i.e., time of use (TOU), real time pricing (RTP), and...
Incorporating time-varying electricity rates into day-ahead distribution system operation
, Article 2014 14th International Conference on Environment and Electrical Engineering, EEEIC 2014 - Conference Proceedings ; 2014 , p. 193-198 ; Abbaspour, A ; Parvania, M ; Fotuhi-Firuzabad, M ; Sharif University of Technology
Abstract
This paper proposes an operation framework for incorporating time-varying electricity rates into day-ahead distribution system operation. The day-ahead distribution system operation problem is formulated as a mixed-integer linear programming (MILP) model, in which profit of the distribution system operator (DSO) from serving local loads is maximized. The impact of time-varying electricity rates on local loads is determined based on the estimated price elasticity of the customers and the historical consumption data. The customers' consumption behaviors in the absence of time-varying electricity rates are captured in terms of the customer baseline load (CBL). The proposed model is applied to a...
Incorporating two-part real-time pricing scheme into distribution system operation
, Article Proceedings - 2014 Electrical Power and Energy Conference, EPEC 2014 ; 2014 , p. 178-183 ; Fotuhi-Firuzabad, M ; Parvania, M ; Abbaspour, A ; Sharif University of Technology
Abstract
Existing real-time pricing (RTP) schemes charge the whole customer's consumption at one highly volatile time varying price, which, in turn, imposes financial risk to participating customers. This paper presents a two-part RTP scheme aiming at efficient distribution system operation while mitigating customers' risk level imposed by volatile RTP prices. Our proposed RTP scheme offers two different RTP price signals. The first RTP price signal is used to charge customer's consumption up to its customer baseline load (CBL) which presents customer's consumption in the absence of RTP signals. The second RTP price signal is announced a day ahead of the actual operation, and can be updated in real...
A practical application of the Delphi method in maintenance-targeted resource allocation of distribution utilities
, Article 2014 International Conference on Probabilistic Methods Applied to Power Systems, PMAPS 2014 - Conference Proceedings ; 2014 ; ISBN: 9781480000000 ; Moeini-Aghtaie, M ; Fotuhi-Firuzabad, M ; Billinton, R ; Sharif University of Technology
Abstract
Trying to find the most efficient and cost-effective decisions on the maintenance of different component types in power distribution systems is an increasingly challenging concern largely driven by the current financial constraints in distribution utilities worldwide. In regard to deal with this challenge, the paper presents a practical application of the Delphi method and the Modified Analytical Hierarchical Process (MAHP) that can be used to find the most critical component types of the system in order to assist in accordingly allocating the available maintenance budget. The proposed approach involves the experience and knowledge held by experts and the historical empirical performance...
Comparative hourly scheduling of centralized and distributed storage in day-ahead markets
, Article IEEE Transactions on Sustainable Energy ; Vol. 5, issue. 3 , 2014 , p. 729-737 ; ISSN: 19493029 ; Fotuhi-Firuzabad, M ; Shahidehpour, M ; Sharif University of Technology
Abstract
Electric energy storage (EES) installations in power systems are migrating from large centralized systems to more distributed installations for microgrid applications. This trend signifies modular EES installations for the local control of buildings and processes. A centralized EES system is often dispatched by grid operators for increasing the overall efficiency and enhancing the security of power systems. The distributed EES (DEES) is locally managed by aggregators to maximize the local impact of EES, before the aggregators' adjusted load profiles are submitted to grid operators for the day-ahead scheduling. In this paper, we present and analyze two models for the hourly scheduling of...
Distribution network reliability improvements in presence of demand response
, Article IET Generation, Transmission and Distribution ; Vol. 8, issue. 12 , 2014 , p. 2027-2035 ; ISSN: 17518687 ; Degefa, M.Z ; Lehtonen, M ; Fotuhi-Firuzabad, M ; Sharif University of Technology
Abstract
Demand response (DR) as a key integral part of the future smart grid is gaining a great and still growing focus of attention in nowadays electric power industries. However, many potential benefits of DR, although they have been envisioned to be significant, have not been yet thoroughly and quantitatively investigated. DR provides network operators with the opportunity to mitigate operational limit violations by load modification in place of load shedding when network reliability is jeopardised. This paper aims to comprehensively assess the potential impacts of DR on major attributes of service reliability in a residential distribution network. For doing so, firstly, load profiles for major...
Optimal demand response aggregation in wholesale electricity markets
, Article IEEE Transactions on Smart Grid ; Vol. 4, issue. 4 , 2013 , p. 1957-1965 ; ISSN: 19493053 ; Fotuhi-Firuzabad, M ; Shahidehpour, M ; Sharif University of Technology
Abstract
Advancements in smart grid technologies have made it possible to apply various options and strategies for the optimization of demand response (DR) in electricity markets. DR aggregation would accumulate potential DR schedules and constraints offered by small- and medium-sized customers for the participation in wholesale electricity markets. Despite various advantages offered by the hourly DR in electricity markets, practical market tools that can optimize the economic options available to DR aggregators and market participants are not readily attainable. In this context, this paper presents an optimization framework for the DR aggregation in wholesale electricity markets. The proposed study...
Improving direct load control implementation by an inititative load control method
, Article EPDC 2013 - 18th Electric Power Distribution Network Conference ; 2013 ; ISBN: 9781480000000 ; Fotuhi-Firuzabad, M ; Moeini-Aghtaie, M ; Sharif University of Technology
Abstract
Demand response (DR) as a state-of-the-art program is accommodated in the energy efficiency contexts of the smart grid. Lack of the customer knowledge about how to respond to the time-differentiated tariffs and offered controlling signals is the major obstacle in the way of broad DR implementing. As a solution, an optimization method, namely load control (LC), is proposed to automatically control the on/off status of the responsive appliances in a smart home. This paper focuses on the direct load control (DLC) program in the category of incentive-based DR programs. LC is extended to consider inconvenience cost of the DLC implementation for DLC program participants. Outputs of the extended LC...
Investigating the impacts of plug-in hybrid electric vehicles on power distribution systems
, Article IEEE Transactions on Smart Grid ; Vol. 4, issue. 3 , 2013 , p. 1351-1360 ; ISSN: 19493053 ; Fotuhi-Firuzabad, M ; Rastegar, M ; Sharif University of Technology
Abstract
Despite the economic and environmental advantages of plug-in hybrid electric vehicles (PHEVs), the increased utilization of PHEVs brings up new concerns for power distribution system decision makers. Impacts of PHEVs on distribution networks, although have been proven to be noticeable, have not been thoroughly investigated for future years. In this paper, a comprehensive model is proposed to study the PHEV impacts on residential distribution systems. In so doing, PHEV fundamental characteristics, i.e., PHEV battery capacity, PHEV state of charge (SOC), and PHEV energy consumption in daily trips, are accurately modeled. As some of these effective characteristics depend on vehicle owner's...
Reliability modeling of dynamic thermal rating
, Article IEEE Transactions on Power Delivery ; Vol. 28, issue. 3 , 2013 , p. 1600-1609 ; ISSN: 8858977 ; Zareipour, H ; Fotuhi-Firuzabad, M ; Sharif University of Technology
Abstract
In this paper, a Markov model for reliability analysis of transmission lines equipped with a dynamic thermal rating (DTR) system is proposed. Moreover, a fuzzy procedure is proposed to determine an annual equivalent fuzzy DTR number to represent hourly variations of the line DTR. To implement the fuzzy annual DTR in composite system reliability analysis, an interactive method resolution technique for solving fuzzy optimization problems is developed. This method is chosen to address the fuzzy constraints associated with the lines equipped with the DTR system. Numerical results are presented using the 24-bus IEEE RTS, and demonstrate the validity of the proposed approaches
Demand response participation in wholesale energy markets
, Article IEEE Power and Energy Society General Meeting ; 2012 ; ISSN: 19449925 ; ISBN: 9781470000000 ; Fotuhi-Firuzabad, M ; Shahidehpour, M ; Sharif University of Technology
Abstract
This paper summarizes a presentation to be given at the IEEE Power and Energy Society 2012 General Meeting, in the panel session Demand response: analytics, practice, and challenges in smart grid environment. The paper elaborates participation of demand response (DR) resources in electricity markets. Specially, different types of DR participation in the wholesale energy markets are discussed. Then, two DR program designs are presented which aim to enable customers' participation in day-ahead energy markets. The paper continues with presenting the modified structure of the day-ahead energy market in presence of the DR programs. The offer packages specifically designed for DR participation in...
Load commitment in a smart home
, Article Applied Energy ; Vol. 96, issue , 2012 , p. 45-54 ; ISSN: 03062619 ; Fotuhi-Firuzabad, M ; Aminifar, F ; Sharif University of Technology
Abstract
Although demand response (DR) potentially brings miscellaneous advantages, it is currently faced with challenges in its implementation due to customers' difficulty in manually responding to the time-varying prices. This paper presents an optimal and automatic residential load commitment (LC) framework to achieve the household minimum payment. Problem decision variables are the operating status of responsive appliances and charging/discharging cycles of battery storage and plug-in hybrid electric vehicles (PHEVs). Storage capability in residential centers provide the customers with this opportunity to not only supply the local demand during the high price hours but also sell the energy back...
Impacts of plug-in hybrid electric vehicle uncertainty and grid unavailability on home load management
, Article 2012 11th International Conference on Environment and Electrical Engineering, EEEIC 2012 - Conference Proceedings ; 2012 , p. 693-698 ; ISBN: 9781460000000 ; Safdarian, A ; Fotuhi-Firuzabad, M ; Aminifar, F ; Sharif University of Technology
Abstract
A massive focus has recently been made on demand response (DR) programs, aimed to the electricity price reduction, reliability improvement, and energy efficiency. Basically, DR programs are divided into twofold main categories, namely incentive-based programs and price- or time-based programs. The focus of this paper is on priced-based DR programs including consumer responses to the time differentiated pricing. Home load management (HLM) program is designed to control responsive appliances and charging/discharging cycles of plug-in hybrid electric vehicles (PHEVs) by the consumer. Uncertain parameters associated with PHEV, i.e. its departure/travelling time and energy consumption as well as...
Post Optimal Analysis application on the reliability evaluation of the Iran power grid
, Article 2012 11th International Conference on Environment and Electrical Engineering, EEEIC 2012 - Conference Proceedings ; 2012 , p. 873-878 ; ISBN: 9781460000000 ; Fotuhi-Firuzabad, M ; Sharif University of Technology
Abstract
Access to a computational tractable method for representing the system more realistically has always been an important issue in power system reliability assessment. The Post Optimal Analysis (POA), as a well recognized technique to attack a set of similar optimization problems, has been successfully used to assess the reliability of composite systems. This method exploits the similarity of the system states to speed up the contingency evaluation procedure without sacrificing the accuracy of the results. In this paper, the performance and practical feasibility of the POA technique for power system reliability evaluation is tested using the Iran power grid. The POA based approach is applicable...