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Value Based Design of Bridges Using Endurance Time Method
, Ph.D. Dissertation Sharif University of Technology ; Esmaeil Purestekanchi, Homayoon (Supervisor)
Abstract
In recent years, due to the economical concerns in the structural design, many researches are devoted to introduce new frameworks for optimization of the construction cost as well as maintenance and rehabilitation costs in the life time. The bridges are the most crucial components of the transportation networks and their appropriate performances assures the flow in the transportation network. Hence, the reliability and response of such infrastructures especially in the emergency conditions and the state of servicibality after the hazards like earthquake play a key role in the social life. So far the design procedure of such infrastructures are only limited to the serviceability conditions as...
Developing a New Method to Estimate Taxing Electricity Sector Carbon Emissions based on Social Cost of Carbon Emissions
, M.Sc. Thesis Sharif University of Technology ; Avami, Akram (Supervisor) ; Moeini Aghtaei, Moein (Co-Supervisor)
Abstract
Controlling, managing, and mitigating the emission of greenhouse gases, especially carbon dioxide, which are produced by human activities, are one of the main concerns of researchers today. Market-based methods are one the successful methods to enhance controlling, managing, and mitigating carbon dioxide emissions, among which the carbon tax has received more attention. Increasing clean technologies in the electricity network to the reduce the emissions of the electricity industry may reduce the carbon tax rate. In this regard, the life cycle analysis makes it possible to consider the emissions of the life cycle. The present model is applied for two representative days of Iran's electricity...
Development of Carbon Management Hierarchy Method Based on Process Integration Techniques
, M.Sc. Thesis Sharif University of Technology ; Avami, Akram (Supervisor)
Abstract
Continuous increase of energy demand, scarcity of resources, as well as environmental limitations have led to the need to reduce carbon emissions. In this research, an MINLP model based on the mathematical optimization formulation is proposed to reach this issue in a large cogeneration unit. Advantage of the hierarchical approach for carbon management are avoiding individual carbon reduction policies, and embedding emission control techniques in a hierarchical mathematical model that helps us to select the most appropriate policies and prioritize each other. In the carbon management hierarchy, the optimization of the base cycle is done at the first stage. Then, the use of renewable energies...
Use of Life Cycle Analysis to Compare Various Vehicle Technologies on Energy Consumption and External Cost for Semi-Public Applications: Case Study, City of Tehran
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Vahid (Supervisor)
Abstract
With the road transportation vehicles being widely used, concerns have been increased regarding their unwanted effects. Air pollution, climate change, and oil supply security are among these effects. Many alternative fuels and propulsion systems have been proposed to be used instead of conventional ICE vehicles in recent decades. This project intends to conduct a Techno-Economic comparison between different vehicle powertrains so as to select the suitable choice to substitute conventional ICE vehicles. The vehicle options are ICE vehicles using both gasoline and CNG as fuels, Hybrid Electric Vehicles (HEVs), Plug-in Hybrid Electric Vehicles (PHEVs), and Electric Vehicles (EVs). The amount of...
Production planning problem with pricing under random yield: CVaR criterion
, Article Journal of Systems Science and Systems Engineering ; Vol. 23, issue. 3 , 2014 , p. 312-328 ; Eshghi, K ; Modarres Yazdi, M ; Bahramgiri, M ; Sharif University of Technology
Abstract
In this paper, we address a basic production planning problem with price dependent demand and stochastic yield of production. We use price and target quantity as decision variables to lower the risk of low yield. The value of risk control becomes more important especially for products with short life cycle. This is because, the profit implications of low yield might be unbearable in the short run. We apply Conditional Value at Risk (CVaR) to model the risk. CVaR measure is a coherent risk measure and thereby having nice conceptual and mathematical underpinnings. It is also widely used in practice. We consider the problem under general demand function and general distribution function of...
Performance-based seismic retrof itting of steel frames by the endurance time method
, Article Earthquake Spectra ; Volume 31, Issue 1 , February , 2015 , Pages 383-402 ; 87552930 (ISSN) ; Estekanchi, H. E ; Sharif University of Technology
Earthquake Engineering Research Institute
2015
Abstract
The endurance time method (ET) is a dynamic analysis procedure in which intensifying dynamic excitations are used as the loading function. Seismic performance is evaluated over the entire range of equivalent seismic intensities of interest in each response history analysis, considerably reducing computational demand. In this paper, a general methodology for performance-based retrof itting of typical steel frames by the ET method is discussed. A baseline steel momentresisting frame is considered, and its seismic performance is evaluated by the ET method, considering viscous dampers and shear wall panels as strengthening alternatives. Each retrof itting option includes several design...
Constitutive modeling of elastic-visco-plastic behaviors in aluminum alloys subjected to cyclic loadings at various strain rates
, Article Journal of Strain Analysis for Engineering Design ; Volume 50, Issue 2 , December , 2015 , Pages 103-124 ; 03093247 (ISSN) ; Azadi, M ; Farrahi, G. H ; Sharif University of Technology
SAGE Publications Ltd
2015
Abstract
In this article, simulations of the stress-strain behavior in aluminum alloys were investigated under cyclic loadings at various strain rates. Four plasticity approaches were applied to simulate cyclic behaviors. To validate obtained results, strain-controlled tensile-compressive fatigue tests were performed in the low cycle fatigue regime. Isothermal fatigue experiments were conducted at various strain rates. Thermo-mechanical fatigue experiments were carried out at different rates of cooling and heating processes. Numerical results demonstrated a good agreement with experimental data at the mid-life cycle of the material. Material constants for different models were also presented for...
A time-cost trade-off model by incorporating fuzzy earned value management: A statistical based approach
, Article Journal of Intelligent and Fuzzy Systems ; Volume 28, Issue 4 , 2015 , Pages 1909-1919 ; 10641246 (ISSN) ; Bagherpour, M ; Reihani, M. H ; Sharif University of Technology
IOS Press
2015
Abstract
Time-cost trade-off problems (TCT) are well-known in project management contents. This approach normally applied for scheduling of a project especially where the project should be completed under pre-determined deadline. This paper aims to extend time-cost trade-off (TCT) problems in order to provide a well-organized mechanism for both scheduling and rescheduling processes of a project. The proposed mechanism includes project scheduling which concerns with the TCT problem, monitoring of project performance during execution phase using earned value management (EVM), and also predicting project future performance through statistical modeling. Once the predicted values of project performance...
Process patterns for aspect-oriented software development
, Article 17th IEEE International Conference and Workshops on the Engineering of Computer-Based Systems, ECBS 2010, 22 March 2010 through 26 March 2010 ; March , 2010 , Pages 241-250 ; 9780769540054 (ISBN) ; Ramsin, R ; Sharif University of Technology
2010
Abstract
Focusing on aspects during early stages of the software development lifecycle has received special attention by many researchers, leading to the advent of numerous Aspect-Oriented Software Development (AOSD) methods. This has consequently given a relatively high level of maturity to aspect-oriented processes. Process patterns, on the other hand, have been adopted as suitable mechanisms for defining or tailoring processes to fit specific organizational/project requirements. Process patterns, which essentially are reusable process components extracted from successful processes and practices, can be used to engineer new software development methodologies or to enhance existing ones. We propose...
Introducing a roadmap to implement the universal manufacturing platform using axiomatic design theory
, Article International Journal of Manufacturing Research ; Volume 5, Issue 2 , 2010 , Pages 252-269 ; 17500591 (ISSN) ; Houshmand, M ; Sharif University of Technology
2010
Abstract
In competitive environment of quick market changes, developing an interoperable manufacturing system is a necessity. To realise interoperability, the exchange of part and product data must be independent of their platforms. There are two basic approaches for this purpose: i utilising interfaces ii utilising neutral formats. Standard for the Exchange of Product data (STEP) plays a significant role as a neutral data model to integrate design, manufacturing and other activities in product life cycle. To implement a Universal Manufacturing Platform (UMP), a systematic roadmap is required. The current paper proposes such a roadmap using the methodology of Axiomatic Design (AD)
From loss allocation to loss cost allocation: a comparative study of different loss cost allocation methods
, Article International Transactions on Electrical Energy Systems ; Volume 23, Issue 4 , 2013 , Pages 586-600 ; 20507038 (ISSN) ; Ehsan, M ; Fotuhi Firuzabad, M ; Parvania, M ; Sharif University of Technology
Abstract
As a high proportion of the total generated electricity energy and the power system costs is due to the power losses in lines, allocating the loss and associated cost to the system loads and generating units is a substantial issue in deregulated power systems. The procedure to accomplish this cost allocation is designated as 'loss cost allocation' (LCA). So far, a number of LCA methods have been proposed for transmission networks. A few papers have compared different loss allocation methods, which are the methods which calculate the loss (and not necessarily the loss cost) allocated to the loads and generating units. However, this paper presents a comparative study of LCA methods. In this...
Configuration design in scalable reconfigurable manufacturing systems (RMS); a case of single-product flow line (SPFL)
, Article International Journal of Production Research ; 2017 , Pages 1-23 ; 00207543 (ISSN) ; Houshmand, M ; Fatahi Valilai, O ; Sharif University of Technology
Abstract
The dynamic nature of today’s manufacturing industry, which is caused by the intense global competition and constant technological advancements, requires systems that are highly adaptive and responsive to demand fluctuations. Reconfigurable manufacturing systems (RMS) enable such responsiveness through their main characteristics. This paper addresses the problem of RMS configuration design, where the demand of a single product varies throughout its production life cycle, and the system configuration must change accordingly to satisfy the required demand with minimum cost. A two-phased method is developed to handle the primary system configuration design and the necessary system...
Production-inventory-routing coordination with capacity and time window constraints for perishable products: heuristic and meta-heuristic algorithms
, Article Journal of Cleaner Production ; Volume 161 , 2017 , Pages 598-618 ; 09596526 (ISSN) ; Niaki, S.T.A ; Aslanzade, S ; Sharif University of Technology
Abstract
Many industries are involved in production and distribution of perishable products. On one hand, due to the short life cycle of these products, there should be more precaution on the issues related to supply chain planning including material requirement planning, production, transportation, etc. compared to the ones in other industries. On the other hand, as there is a fierce competition among various companies, the need for coordination in such activities is imperative, where the use of an integrated approach is justifiable. One of these coordination problems is how to integrate important operational decisions including production scheduling and vehicle routing problem; the most important...
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) ; 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...
Configuration design in scalable reconfigurable manufacturing systems (RMS); a case of single-product flow line (SPFL)
, Article International Journal of Production Research ; Volume 56, Issue 11 , 2018 , Pages 3932-3954 ; 00207543 (ISSN) ; Houshmand, M ; Fatahi Valilai, O ; Sharif University of Technology
Taylor and Francis Ltd
2018
Abstract
The dynamic nature of today’s manufacturing industry, which is caused by the intense global competition and constant technological advancements, requires systems that are highly adaptive and responsive to demand fluctuations. Reconfigurable manufacturing systems (RMS) enable such responsiveness through their main characteristics. This paper addresses the problem of RMS configuration design, where the demand of a single product varies throughout its production life cycle, and the system configuration must change accordingly to satisfy the required demand with minimum cost. A two-phased method is developed to handle the primary system configuration design and the necessary system...
Integrated forward and reverse logistics in cloud manufacturing: an agent-based multi-layer architecture and optimization via genetic algorithm
, Article Production Engineering ; Volume 15, Issue 6 , 2021 , Pages 801-819 ; 09446524 (ISSN) ; Akbaripour, H ; Houshmand, M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
Cloud manufacturing (CMfg) is a new service-oriented manufacturing paradigm that enables distributed collaboration between manufacturers. As logistics between geographically dispersed manufacturers is indispensable in CMfg environment, and the responsibility for the whole lifecycle of products becomes more important for manufacturers, we have taken into account both forward and reverse logistics services in CMfg. Unlike most of the research in the field, this paper not only addresses the special needs of CMfg system from reverse logistics perspective but also considers the transportation of returned products. For this purpose, an agent-based architecture for tackling reverse flows in CMfg is...
Energy and economic analysis of model-based air dampers strategies on a VAV system
, Article International Journal of Environmental Science and Technology ; Volume 16, Issue 8 , 2019 , Pages 4687-4696 ; 17351472 (ISSN) ; Sharif University of Technology
Center for Environmental and Energy Research and Studies
2019
Abstract
A variable air volume (VAV) air handling system can significantly reduce fan power under partial load conditions. The focus of this study is developing a modeling program to predict the potential energy saving by the secondary HVAC system strategies. Comprehensive steady-state models are established to describe the energy performance of different control strategies for secondary HVAC systems. With building loads, minimum fresh air flow rate, pressure losses, supply air temperature control, dampers control and coil characteristic as inputs, the objectives were to develop a simulation model to evaluate performance of an air handling system. The potential energy savings of constant air volume...
Economic and environmental assessment of a solar-assisted ground source heat pump system in a heating-dominated climate
, Article International Journal of Environmental Science and Technology ; Volume 16, Issue 7 , 2019 , Pages 3091-3098 ; 17351472 (ISSN) ; Saidi, M. H ; Abbaspour, M ; Sharif University of Technology
Center for Environmental and Energy Research and Studies
2019
Abstract
In recent years, increasing attention has been paid to the use of renewable energy sources in building sector. The ground source heat pumps are a promising alternative for heating and cooling applications. Despite the high coefficients of performance and significant environmental benefits, their performance may deteriorate over the long-term operation if the annual ground loads are not well balanced. An appropriate solution is the use of hybrid ground source heat pump system through which some portion of the thermal loads can be offset by supplemental components. The aim of this study is to assess the feasibility of a solar-assisted ground source heat pump system for heating a detached house...
Development of a framework for the sustainability evaluation of renewable and fossil fuel power plants using integrated LCA-emergy analysis: A case study in Iran
, Article Renewable Energy ; Volume 179 , 2021 , Pages 1548-1564 ; 09601481 (ISSN) ; Avami, A ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
This study presents a comprehensive framework for evaluating renewable and non-renewable power plants' performance using the Life Cycle Analysis (LCA) and emergy analysis. The emergy analysis is used to consider the free ecosystem services in the sustainability of the systems as a supplement to the LCA. The results indicate that the wind and photovoltaic power plants have the best performance in terms of the LCA analysis, while the wind and combined cycle power plants have the highest emergy sustainability index. The best scenario is chosen under a two-objective optimization problem, including the single score and emergy sustainability as objective functions. Here, the wind power plant is...
Development of a framework for the sustainability evaluation of renewable and fossil fuel power plants using integrated LCA-emergy analysis: a case study in Iran
, Article Renewable Energy ; Volume 179 , 2021 , Pages 1548-1564 ; 09601481 (ISSN) ; Avami, A ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
This study presents a comprehensive framework for evaluating renewable and non-renewable power plants' performance using the Life Cycle Analysis (LCA) and emergy analysis. The emergy analysis is used to consider the free ecosystem services in the sustainability of the systems as a supplement to the LCA. The results indicate that the wind and photovoltaic power plants have the best performance in terms of the LCA analysis, while the wind and combined cycle power plants have the highest emergy sustainability index. The best scenario is chosen under a two-objective optimization problem, including the single score and emergy sustainability as objective functions. Here, the wind power plant is...