Sharif Digital Repository

In the past, decision making within the energy sector, especially in Iran, was limited to economic analysis. Lately, multiple criteria decision making has gained great popularity. However, this is not enough to make a right decision by considering sustainability. This paper deals with designing an appropriate multiple criteria decision making method to address the multifaceted nature of such problems. This task is the second precondition to make a decision which meets the sustainability criterion. This is done by revealing new facts about quantitative and qualitative data and the degree of compensation between the criteria. Moreover, this paper illustrates the capability of different methods... 

The aim of the present study is to provide an Atlas of IRAN Offshore Renewable Energy Resources (hereafter called 'the Atlas') to map out wave and tidal resources at a national scale, extending over the area of the Persian Gulf and Sea of Oman. Such an Atlas can provide necessary tools to identify the areas with greatest resource potential and within reach of present technology development. To estimate available tidal energy resources at the site, a two-dimensional tidally driven hydrodynamic numerical model of Persian Gulf was developed using the hydrodynamic model in the MIKE 21 Flow Model (MIKE 21HD), with validation using tidal elevation measurements and tidal stream diamonds from... 

We develop a heuristic procedure for solving the discrete time/resource trade-off problem in the field of project scheduling. In this problem, a project contains activities interrelated by finish-start-type precedence constraints with a time lag of zero, which require one or more constrained renewable resources. Each activity has a specified work content and can be performed in different modes, i.e. with different durations and resource requirements, as long as the required work content is met. The objective is to schedule each activity in one of its modes in order to minimize the project makespan. We use a scatter search algorithm to tackle this problem, using path relinking methodology as... 

Graft copolymerization of methyl methacrylate (MMA) was carried out on bagasse fibers in an aqueous medium using eerie ammonium nitrate (CAN) as initiator under a neutral atmosphere. In order to obtain the optimum condition for graft copolymerization, the effects of initiator concentration, temperature, time of reaction, and monomer concentration were studied. The maximum grafting percent was found to be 122%. The bagasse grafted poly(methyl methacrylate) was characterized by FTIR and its thermal behavior was characterized by TGA. Copyright © 2008 WILEY-VCH Verlag GmbH & Co. KGaA  

In this paper, a new approach to formulate a class of scheduling problems is introduced, which can be applied to many other discrete problems with complicated structures. The concept of graph circular coloring is applied to develop a model for the special case of an open shop scheduling problem. In this problem, there are some independent jobs to be processed in a shop with dedicated renewable resources. Each job consists of several tasks with no precedence restriction. Each task is processed without preemption. The processing time of the tasks is given. Processing each task requires using some multiple specified types of resource, while no more than one task can use each resource,... 

A lot of projects in real life are subject to some kinds of nonrenewable resources that are not exactly similar to the type defined in the project scheduling literature. The difference stems from the fact that, in those projects, contrary to the common assumption in the project scheduling literature, nonrenewable resources are not available in full amount at the beginning of the project, but they are procured along the project horizon. In this paper, we study this different type of nonrenewable resources. To that end, we extend the resource constrained project scheduling problem (RCPSP) by this resource type (RCPSP-NR) and customize four basic branch and bound algorithms of RCPSP for it,... 

Recent advancements in photovoltaic (PV) system technologies have decreased their investment cost and enabled the construction of large PV farms for bulk power generations. The output power of PV farms is affected by both failure of composed components and solar radiation variability. These two factors cause the output power of PV farms be random and different from that of conventional units. Therefore, suitable models and methods should be developed to assess different aspects of PV farms integration into power systems, particularly from the system reliability viewpoint. In this context a reliability model has been developed for PV farms with considering both the uncertainties associated... 

A new strategy for enhancing the efficiency and reducing the production cost of TiO 2 solar cells by design of a new formulated TiO 2 paste with tailored crystal structure and morphology is reported. The conventional three- or four-fold layer deposition process was eliminated and replaced by a single layer deposition of TiO 2 compound. Different TiO 2 pastes with various crystal structures, morphologies and crystallite sizes were prepared by an aqueous particulate sol-gel process. Based on simultaneous differential thermal (SDT) analysis the minimum annealing temperature to obtain organic-free TiO 2 paste was determined at 400°C, being one of the lowest crystallization temperatures of TiO 2... 

In order to decrease CO 2 emission into the atmosphere and develop renewable energy sources for carbon capture, an integrated system is considered for co-production of electricity and methanol. In this research, methanol synthesis unit through captured CO 2 from fossil fuel power plant and produced H 2 from water electrolysis unit by wind renewable energy is developed. An oxy-fuel combustion carbon capture method is considered in large scale Matiant power plant based on utilization of oxygen from water electrolysis unit. Technical and economical analysis of the proposed system shows that when the price of natural gas is 7.8US$/GJ, the total CO 2 avoided cost is 93US$/(tonne of CO 2) and... 

We present an optimal solution procedure for minimizing total weighted resource tardiness penalty costs in the resource-constrained project scheduling problem. In this problem, we assume the constrained renewable resources are limited to very expensive equipments and machines that are used in other projects and are not available in all periods of time of a project. In other words, for each resource, there is a dictated ready date as well as a due date such that no resource can be available before its ready date but the resources are permitted to be used after their due dates by paying penalty cost depending on the resource type. We also assume that only one unit of each resource type is... 

This paper formulates flow of energy from primary resources and import routes to different socio-economic sectors by making use of Long-Range Energy Alternatives Planning (LEAP) model. It presents a baseline of how Iran’s future production and consumption patterns evolve. It also seeks plausible scenario for renewable energies utilization and evaluates its mitigation potential and economic aspects. Model results indicate that exploitation of a "not-too-strict" package of renewable sources featuring 10 GW of wind and 19 GW of hydro by the end of 2035 will lead to CO2 emissions to be reduced up to an amount of 190.7 million tons in the study period. By accounting for the opportunity costs... 

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... 

Increased electricity demand coupled with investment in renewable-based generating units has resulted in problems such as transmission congestion and load shedding in modern power systems. In this situation, transmission expansion planning (TEP) studies plays a key role in dealing with the aforementioned problems. On the other hand, deployment of energy storage systems (ESSs) has been regarded as a viable solution for effective exploitation of renewable resources. In this context, this paper develops a novel framework to investigate the impacts of storage facilitates on the transmission expansion planning problem. The presented framework is decomposed to investment and operation subproblems... 

Over the recent decades, many different ducted turbines have been designed to augment efficiency of wind turbines. The design and number of blades are the most important parameters to optimize efficiency of wind turbines. In this paper, effects of design, number and attack angles of blades on rotational speed are experimentally studied in a duct which increases wind velocity up to 2.46 times numerically and 2.32 times experimentally as great as far-field flow. In order to realize this, 3 different types of aerodynamic blades were designed and then, 2-bladed, 3-bladed and 4-bladed impellers were created by these blades; finally, 9 impellers were built on aggregate. The rotational speed of...