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    Parallel Layers of Strategic Renewal and the Leveraging Role of Organizational Structure

    , Ph.D. Dissertation Sharif University of Technology Aghajanian, Simineh (Author) ; Mashayekhi, Ali Naghi (Supervisor) ; Alavi, Babak (Co-Supervisor)
    Abstract
    One of the research areas less-addresses in the field of strategy – especially with a process approach – is strategic renewal. Strategic renewal is crucial for sustainable success of an organization. However, there are limited studies focused on strategic renewal, its implementation, and factors affecting its successive success. Process view is also less applied despite its importance both in understanding different steps of renewal and determining motivators and impediments. Therefore, this study tries to do a process-oriented research on strategic renewal, considering the gaps in extant process models on renewal. For this aim, an embedded single case study is applied and some successful... 

    Assessment of barriers to renewable energy development using stakeholders approach

    , Article Entrepreneurship and Sustainability Issues ; Volume 7, Issue 3 , March , 2020 , Pages 2526-2541 Nasr, A. K ; Kashan, M. K ; Maleki, A ; Jafari, N ; Hashemi, H ; Sharif University of Technology
    Entrepreneurship and Sustainability Center  2020
    Abstract
    Typically, the lack of effective stakeholder participation in a project—especially in the initial planning and implementation stages—has a negative impact on the expected performance of the project. These negative consequences require attempts to encourage their effective participation. Nevertheless, there are some challenges ahead, such as conflict of interest among the stakeholders. For more accurate identification of the interests, objectives, and performance of the stakeholders, this paper proposes an accurate and organized model for the analysis of results from the stakeholder impact index. We implemented the proposed model to determine the existing barriers to renewable energy... 

    Optimal design of stand-alone PV/ wind generator and diesel system by using individual particle optimization algorithm

    , Article International Review of Electrical Engineering ; Vol. 7, issue. 5 , 2012 , p. 5474-5486 ; ISSN: 18276660 Ahmari-Nezhad, A ; Abbaspour-Tehrani-Fard, A ; Ehsan, M ; Fotuhi-Firuzabad, M ; Abroshan, M ; Sharif University of Technology
    Abstract
    In this paper an optimized wind/PV hybrid system with battery and diesel backup is designed. As a result of this study the costs of the hybrid system will be minimized in its 20-year life time. The optimization is done by considering the annual load increase and fuel cost rise. This Optimization is subject to load covering and minimizing the total cost. The total cost entailed maintenance, equipment and diesel fuel consumption substitution. An advanced variation of individual particle optimization algorithm (IPO) is used to solve the optimization problem  

    A note on optimal price, warranty length and production rate for free replacement policy in static demand markets

    , Article Omega ; Volume 40, Issue 6 , 2012 , Pages 805-806 ; 03050483 (ISSN) Faridimehr, S ; Niaki, S. T. A ; Sharif University of Technology
    2012
    Abstract
    This note provides some extensions on optimal policies on price, warranty length and production rate proposed by Wu et al. (2009) . [1] (Wu, C.C.; Chou, C.Y.; Huang C. Optimal price, warranty length and production rate for free replacement policy in the static demand market. Omega 2009; 37: 29-39.) More specifically, the assumptions of the original paper is extended in this note from the production rate being positive and the second derivative of the demand function with respect to price and warranty-length being negative to no restrictions on both  

    Erratum: Determination of price and warranty length for a normal lifetime distributed product (International Journal of Production Economics (2006) 102: 1 (95-107))

    , Article International Journal of Production Economics ; Volume 137, Issue 2 , Volume 137, Issue 2 , 2012 , Pages 309-310 ; 09255273 (ISSN) Faridimehr, S ; Akhavan Niaki, T ; Sharif University of Technology
    2012
    Abstract
    This paper points out a flaw in the derivation of the optimal price and warranty length policies proposed by Wu et al. (2006) (Wu, C.C., Lin, P.C., Chou, C.Y. Determination of price and warranty length for a normal lifetime distributed product. International Journal of Production Economics 102 (2006): 95–107). While we show one of the optimal strategies that they considered is incorrect, correct versions of the optimal strategies are presented  

    Optimum sizing and siting of renewable-energy-based dg units in distribution systems

    , Article Optimization in Renewable Energy Systems: Recent Perspectives ; 2017 , Pages 233-277 ; 9780081012093 (ISBN); 9780081010419 (ISBN) Arabali, A ; Ghofrani, M ; Bassett, J. B ; Pham, M ; Moeini Aghtaei, M ; Sharif University of Technology
    Elsevier Inc  2017
    Abstract
    The increasing demand for clean and nonfossil energy has escalated the integration of renewable power sources into the distribution system. Renewable distributed generators (DGs) have the potential to reduce the environmental impact when the integration into the distribution system is carefully optimized. However, serious technical issues will be raised when the integration is not properly implemented. This chapter presents optimal siting and sizing of renewable DG units within distribution systems. Both deterministic and probabilistic models of renewable-based DG units will be discussed in details along with characteristics of well-known renewable generators. The effects of DGs on... 

    On the way of policy making to reduce the reliance of fossil fuels: Case study of Iran

    , Article Sustainability (Switzerland) ; Volume 12, Issue 24 , 2020 , Pages 1-28 Aien, M ; Mahdavi, O ; Sharif University of Technology
    MDPI AG  2020
    Abstract
    Nowadays, fossil fuels are well known as a predominant source of energy in the planet. Located in the Middle East region, Iran holds one of the largest fossil fuel reservoirs in the world. The country has abundant oil and natural gas fields in various regions; some of them are shared between other countries and have not reached their operational capacity yet. Meanwhile, during recent years and due to global warming followed by environmental global contracts such as Kyoto protocol, using fossil fuels is being criticized to a large extent around the world. Therefore, the global interest has been focused toward clean energy resources. Furthermore, endowed with sundry geographical pattern... 

    A data-driven robust optimization for multi-objective renewable energy location by considering risk

    , Article Environment, Development and Sustainability ; 2022 ; 1387585X (ISSN) Lotfi, R ; Kargar, B ; Gharehbaghi, A ; Afshar, M ; Rajabi, M. S ; Mardani, N ; Sharif University of Technology
    Springer Science and Business Media B.V  2022
    Abstract
    Using Renewable Energy (RE) is growing day by day. We need to locate RE in the best place to maximize energy production and supplier profit. As a result, we propose a novel method for RE location (REL). This model suggests a Data-Driven Robust Optimization (DDRO) for multi-objective REL by considering Risk (DDROMORELR). We consider risk by adding min function in energy and profit objectives (government and supplier objectives). A DDRO approach is added to the model to tackle uncertainty and be close to the real world. We utilize an improved Augmented ε-constraint (AUGEPS2) to solve objectives and produce a Pareto front. We compare problems with DDRO and without considering DDRO, and the... 

    Blockchain technology application challenges in renewable energy supply chain management

    , Article Environmental Science and Pollution Research ; 2022 ; 09441344 (ISSN) Almutairi, K ; Hosseini Dehshiri, S. J ; Hosseini Dehshiri, S. S ; Hoa, A. X ; Arockia Dhanraj, J ; Mostafaeipour, A ; Issakhov, A ; Techato, K ; Sharif University of Technology
    Springer Science and Business Media Deutschland GmbH  2022
    Abstract
    With the advent of new technologies and globalization of business, supply chains have turned into indispensable tools for gaining competitive advantage. The application of new technologies like blockchain can benefit sustainable energy supply chains by improving chain and logistics operations in the areas of trust, transparency and accountability, cooperation, information sharing, financial exchanges, and supply chain integration. However, the efforts to adopt such technologies in supply chains tend to face many challenges and challenges, which can seriously threaten their success. Therefore, it is crucial to carefully examine the challenges to blockchain technology application. This... 

    Maximizing the utilization of existing grids for renewable energy integration

    , Article Renewable Energy ; Volume 189 , 2022 , Pages 618-629 ; 09601481 (ISSN) Ranjbar, H ; Kazemi, M ; Amjady, N ; Zareipour, H ; Hosseini, S. H ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    This paper presents a new model to maximize the utilization of existing transmission system infrastructure by optimally sizing and siting the future developments of variable renewable energy sources (VRES). The model tries to maximize the integration of VRES in power systems with minimum expected energy curtailment without relying on new investments in the transmission systems. The proposed model is formulated as a linear stochastic programming optimization problem where VRES output scenarios are generated such that their spatio-temporal correlations are maintained. The Progressive Hedging Algorithm (PHA) with bundled scenarios is utilized to solve the proposed model for large-scale cases.... 

    Multi-objective optimization of direct coupling photovoltaic-electrolyzer systems using imperialist competitive algorithm

    , Article ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE) ; Vol. 6A , November , 2014 Maroufmashat, A ; Sayedin, F ; Sattari, S ; Sharif University of Technology
    Abstract
    Photovoltaic-electrolyzer systems are one of the most promising alternatives for obtaining hydrogen from a renewable energy source. Determining size and the operational conditions are always a key issue while coupling directly renewable electricity sources to PEM electrolyzer. In this research, the multi objective optimization approach based on an imperialist competitive algorithm (ICA), which is employed to optimize the size and the operating conditions of a directly coupled photovoltaic (PV)-PEM electrolyzer. This allows the optimization of the system by considering two different objectives, including, minimization of energy transfer loss and maximization of hydrogen generation. Multi... 

    Highly selective doped Pt[sbnd]MgO nano-sheets for renewable hydrogen production from APR of glycerol

    , Article International Journal of Hydrogen Energy ; Volume 41, Issue 39 , 2016 , Pages 17390-17398 ; 03603199 (ISSN) Larimi, A. S ; Kazemeini, M ; Khorasheh, F ; Sharif University of Technology
    Elsevier Ltd  2016
    Abstract
    A series of M-doped Pt[sbnd]MgO (M = Pd, Ir, Re, Ru, Rh and Cr) sheet-shaped nano-catalysts were synthesized by the controlled co-precipitation method. The effects of M-doping on both the physicochemical and the chemisorption characteristics of Pt[sbnd]MgO catalysts were examined. The performance of the catalysts for the aqueous phase reforming (APR) of glycerol was also investigated. The APR activity of Pt[sbnd]M[sbnd]MgO catalysts depended on the type of the M dopant used. The APR activity varied in the following order: Rh > Pd > Cr > Ir > undoped ≈ Ru > Re, with the Rh-promoted catalyst having an activity of about one order of magnitude higher than the Re-promoted catalyst at 250 °C. It... 

    Value of distribution network reconfiguration in presence of renewable energy resources

    , Article IEEE Transactions on Power Systems ; Volume 31, Issue 3 , 2016 , Pages 1879-1888 ; 08858950 (ISSN) Dorostkar Ghamsari, M. R ; Fotuhi Firuzabad, M ; Lehtonen, M ; Safdarian, A ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc 
    Abstract
    Proliferation of renewable energy resources in distribution networks has captured distribution companies' attention towards more active management tools. Thanks to the smart grid paradigm, hourly network reconfiguration, which is still among immature ideas, can bring the activeness required to handle fluctuating output of renewable resources. The aim of this study is to analyze the worthiness of the hourly reconfiguration in the presence of renewable energy resources. For doing so, a mathematical model is devised to minimize daily network losses via applying hourly reconfigurations. The model is a mixed integer second-order cone programming problem and is solved via MOSEK solver. The... 

    Optimal planning of hybrid renewable energy infrastructure for urban sustainability: Green Vancouver

    , Article Renewable and Sustainable Energy Reviews ; Volume 95 , 2018 , Pages 254-264 ; 13640321 (ISSN) Bagheri, M ; Shirzadi, N ; Bazdar, E ; Kennedy, C. A ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    Despite the great promise of hybrid solar-wind-biomass energy systems to power future sustainable cities, complexities associated with their optimal planning and design limit their wide-scale implementation. This study provides a novel systematic framework to identify optimal hybrid renewable solutions for urban areas at neighborhood scales. In particular, we examine the role of economies of scale in the techno-economic feasibility and environmental performance of hybrid renewable systems. For demonstration, we assess the impact of the economics of scale (at the neighborhood scales of 1/500, 1/250, and 1/100 of the city's electrical load) on the life-cycle costs of optimal hybrid renewable... 

    Distribution grid flexibility-ramp minimization using local resources

    , Article 2019 IEEE PES Innovative Smart Grid Technologies Europe, ISGT-Europe 2019, 29 September 2019 through 2 October 2019 ; 2019 ; 9781538682180 (ISBN) Fattaheian Dehkordi, S ; Tavakkoli, M ; Abbaspour, A ; Fotuhi Firuzabad, M ; Lehtonen, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    Abstract
    Increasing rate of renewable energy sources (RESs) integration in the distribution system and development of multi-microgrids (MMG) structures have changed the operational condition of power grids. In this context, the stochastic and intermittent nature of the RESs has increased the need for ramp up power to balance the supply and demand when electricity generation of these resources drops. Moreover, bulk power generation units, which conventionally have the possibility to provide flexibility ramp, would face lack of financial justification for expansion and operation in a system with high rate penetration of RESs. Therefore, distribution system operators (DSOs) should rely on local... 

    Renewable hydrogen production over Pt/Al₂O₃ nano-catalysts: Effect of M-promoting (M=Pd, Rh, Re, Ru, Ir, Cr)

    , Article International Journal of Hydrogen Energy ; Volume 44, Issue 16 , 2019 , Pages 8243-8251 ; 03603199 (ISSN) Larimi, A ; Khorasheh, F ; Sharif University of Technology
    Elsevier Ltd  2019
    Abstract
    Xwt% Pt/Al 2 O 3 (X = 1, 3, 5, 8, 10) and 5 wt% Pt-1wt% M/AlO 3 (M = Pd, Rh, Re, Ru, Ir, Cr) catalysts were prepared, characterized and tested for aqueous phase reforming of pure and crude glycerol. Results show drastic dependence of catalytic performance of catalysts on both the active metal loading and the type of applied promoters. 5 wt% was the best Pt loading and Pt[sbnd]Rh/Al₂O₃ shows the best catalytic activity which has the highest hydrogen production rate (mmol/g cat h −1 ) and selectivity (89%) in continuous aqueous phase reforming of 10 wt% pure glycerol solution  

    Robust energy management of residential energy hubs integrated with power-to-x technology

    , Article 2021 IEEE Texas Power and Energy Conference, TPEC 2021, 2 February 2021 through 5 February 2021 ; 2021 ; 9781728186122 (ISBN) Habibifar, R ; Khoshjahan, M ; Saravi, V. S ; Kalantar, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2021
    Abstract
    Growing interest in the intermittent renewable energy sources may jeopardize the flexibility of power systems. In order to improve the flexibility of modern power systems, the surplus electricity generated by renewable sources can be deployed into several carriers, such as natural gas and heating energy via power-to-gas (PtG) and power-to-heat (PtH) technologies. This paper proposes an optimal daily energy management model of residential energy hubs integrated with power-to-X technologies. The proposed energy hub is incorporated with PtG, PtH, combined heat and power (CHP) facilities, and thermal storage to meet the required electrical, gas, and heating demands. In order to capture the... 

    Integrating load reduction into wholesale energy market with application to wind power integration

    , Article IEEE Systems Journal ; Vol. 6, issue. 1 , 2012 , p. 35-45 ; ISSN: 19328184 Parvania, M ; Fotuhi-Firuzabad, M ; Sharif University of Technology
    Abstract
    Renewable energy resources, notably wind power, are expected to provide considerable portion of the world energy requirements in the near future. Many system operators around the world are challenged by the problems associated with integrating these intermittent resources into the grid. As one of the potential solutions, demand response (DR) is expected to play a major role for mitigating integration issues of intermittent renewable energy resources. In this context, this paper proposes a DR program which helps to integrate wind power by reshaping the load of the system. The DR program provides a framework to procure load reduction from DR resources in the wholesale energy market. The... 

    Pricing of Vehicle-to-Grid Services in a Microgrid by Nash Bargaining Theory

    , Article Mathematical Problems in Engineering ; Volume 2017 , 2017 ; 1024123X (ISSN) Sarparandeh, M. H ; Ehsan, M ; Sharif University of Technology
    Hindawi Publishing Corporation  2017
    Abstract
    Owners of electric vehicles (EVs) can offer the storage capacity of their batteries to the operator of a microgrid as a service called vehicle-to-grid (V2G) to hold the balance between supply and demand of electricity, particularly when the microgrid has intermittent renewable energy sources. Literature review implies that V2G has economic benefits for both microgrid operator and EV owners, but it is unclear how these benefits are divided between them. The challenge grows when the policy makers rely on the V2G revenue as an incentive for expanding the penetration of EVs in the automotive market. This paper models the interaction between microgrid operator and EV owners as a bargaining game... 

    Main challenges of implementing penalty mechanisms in transactive electricity markets

    , Article IEEE Transactions on Power Systems ; Volume 34, Issue 5 , 2019 , Pages 3954-3956 ; 08858950 (ISSN) Ghorani, R ; Fotuhi Firuzabad, M ; Moeini Aghtaie, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    Abstract
    Efficient operation of electricity markets necessitates a penalty mechanism to penalize market participants who do not fulfill their market obligations. However, the traditional penalty mechanisms that have been successfully implemented in wholesale electricity markets may result in unintended consequences in transactive markets where the participants have uncertain supply or demand. In this regard, this letter investigates main challenges of applying traditional penalty mechanisms in transactive energy markets. Some efficient strategies are also proposed to operate the transactive markets in such a way that guarantees its security as well as liquidity. © 1969-2012 IEEE