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    The significance of domino effect in chemical accidents

    , Article Journal of Loss Prevention in the Process Industries ; Vol. 29, issue. 1 , May , 2014 , pp. 30-38 ; ISSN: 09504230 Hemmatian, B ; Abdolhamidzadeh, B ; Darbra, R. M ; Casal, J ; Sharif University of Technology
    Abstract
    A historical survey was performed on 330 accidents involving domino effect, occurred in process/storage plants and in the transportation of hazardous materials; only accidents occurred after 1st-January-1961 have been considered. The main features - geographical location, type of accident, materials involved, origin and causes, consequences, domino sequences - were analyzed, with special consideration to the situation in the developing countries and compared to those from other previous surveys. Among the involved substances, LPG was the most frequent one, followed by liquid hydrocarbons. Process plants (38.5% of cases) and storage areas (33%) were the most common settings; 10.6% of past... 

    Quantitative Risk Assessment of Domino Accidents

    , M.Sc. Thesis Sharif University of Technology Rad, Amir Hossein (Author) ; Rashtchian, Davood (Supervisor)
    Abstract
    Domino accidents are those which are initiated from one equipment and extend to neighbor equipments or units and as a result the consequence of the primary accident is increased. Risk management is one of the tools for reducing risk of accidents and Quantitative Risk Analysis is a crucial stage in risk management. Despite the importance and severity of domino accidents, in most of QRA studies the effect of these accidents on risk is not considered. In the present work tools for Quantitative Risk Analysis with considering domino accidents has been developed. Two major methods for this reason are used; analytical method and simulation. First, software based on analytical method was developed... 

    Risk analysis of liquefaction potential in South West Tehran

    , Article Amirkabir (Journal of Science and Technology) ; Volume 15, Issue 58 D , 2004 , Pages 521-534 ; 10150951 (ISSN) Hamidi, A ; Haeri, S. M ; Shirazi, A ; Olyaei, M. N ; Bakhshi, A ; Sharif University of Technology
    2004

    An Economic-Financial Model for Response to Earthquake in Conditions of Uncertainty with a Case Study of an Earthquake Event in a Small Town

    , M.Sc. Thesis Sharif University of Technology Bostanara, Maryam (Author) ; Eshghi, Kourosh (Supervisor)
    Abstract
    Annually Natural disasters make tremendous impacts on societies. Fatality rate of earthquake in Iran is almost more than all other disasters. There are numerous problems in disaster Management's of Iran and other countries. One of the disaster Management's phases is response phase which mostly depends on emergency processes, so most of papers working on this phase, plan for emergency state by using different techniques.All the studies seeking the response phase, try to reduce the loss of disaster by the use of immediate response to earthquake, pointing the disaster after occurrence. But Another point of view is to make loss reduction by precautious activities and plans. Actually, the loss... 

    , M.Sc. Thesis Sharif University of Technology Darabi, Meisam (Author) ; Rashtchian, Davood (Supervisor)
    Abstract
    Emergency Shut Down systems are considered as one of the prominent protection layers in industries. In the situation that the process variables exist acceptable limits, the SIS brings the process in a safe state. According to standards, separate design and operation have been defined for BPCS and SIS. In this research, safety issues related to one of the gas refinery unit has been investigated. In fact, the unit does not have shut down system and all the safety loops are defined as DCS. In the first step, the Safety Integrated Levels of the loops which must be defined in shut down system have been specified by using Modified Calibrated Risk Graf. In next step, philosophy of shut down levels... 

    Analysis of Launch Time in New Product Development With Risk Considerations

    , M.Sc. Thesis Sharif University of Technology Sadat Sharifonnasabi, Zahra (Author) ; Sheikhzadeh, Mehdi (Supervisor)
    Abstract
    The importance of New Product Development (NPD) projects has been realized more and more in recent years. Among different decisions to be made in NPD process, one of the most critical decisions is about the best time to launch new product(s). Due to existence of many internal and external influential factors, determining the optimal launch time is often too complicated and it is quite hard to systematically analyze it. Despite risky nature of NPD, risk considerations in determining the optimal launch time have not been addressed in literature due to the mentioned complexity. In this research, we developed a model that takes in to account risk considerations while systematically determining... 

    Product bundling: Impacts of product heterogeneity and risk considerations

    , Article International Journal of Production Economics ; Volume 144, Issue 1 , July , 2013 , Pages 209-222 ; 09255273 (ISSN) Sheikhzadeh, M ; Elahi, E ; Sharif University of Technology
    2013
    Abstract
    Bundling has been extensively studied in the literature and its benefits have been manifested through three perspectives of achieving better price discrimination, helping to save costs, and preserving the power for deterring a potential entrant. In this study, we examine two aspects of bundling which have not been studied before. We examine the impact of product heterogeneity on bundling decisions. We also address risk considerations in a bundling problem. Specifically, we consider a retailer who has the option of selling a bundle of two products (pure bundling policy), or selling the products separately (no-bundling policy). The retailer could also face a product selection problem for which... 

    Perception and Communication of Seismic Risk: Design and Implementation of a Functional Tool

    , Article Natural Hazards Review ; Volume 19, Issue 2 , 2018 ; 15276988 (ISSN) Ghasemi, A ; Mahsuli, M ; Mortazavi, S. M. S ; Sharif University of Technology
    American Society of Civil Engineers (ASCE)  2018
    Abstract
    A web-based system is designed and implemented as a risk communication tool to incentivize the public to take seismic risk mitigation measures. Risk denotes the expected monetary and social losses herein. The objective of this system is to raise the awareness of two audience groups, the general public and decision makers, about significant seismic risk in Iran. To address the general public, the system employs the notion of risk perception to put the results of sophisticated earthquake engineering risk analyses into perspective. The system also treats the epistemic uncertainty of user input due to the public's lack of technical knowledge through the notion of entropy in information theory.... 

    Dynamic risk assessment of decommissioning offshore jacket structures

    , Article Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE, 17 June 2018 through 22 June 2018 ; Volume 3 , 2018 ; 9780791851227 (ISBN) Babaleye, A ; Khorasanchi, M ; Kurt, R. E ; Ocean, Offshore and Arctic Engineering Division ; Sharif University of Technology
    American Society of Mechanical Engineers (ASME)  2018
    Abstract
    The need to develop an integrated dynamic safety and risk analysis model for decommissioning offshore jacket structures is driven by the risky, expensive and complex nature of the operation. Many of the existing risk analysis techniques applicable to offshore assets failed to recognise and capture evolving risks during different stages of the decommissioning operation. This paper describes risk-based safety model to conduct quantitative risk analysis for offshore jacket decommissioning failure. First, a bow-tie technique is developed to model the accident cause-consequence relationship. Subsequently, a Bayesian belief network is used to update the failure probabilities of the contributing... 

    Value based seismic design of structures using performance assessment by the endurance time method

    , Article Structure and Infrastructure Engineering ; Volume 16, Issue 10 , January , 2020 , Pages 1397-1415 Mirfarhadi, S. A ; Estekanchi, H. E ; Sharif University of Technology
    Taylor and Francis Ltd  2020
    Abstract
    A framework for optimal seismic design of structures, considering maximum value as the design objective, is introduced. In this framework, the value parameter incorporates a comprehensive set of performance indicators. Decision indicators are mapped into equivalent economic values and are directly involved in the design process. This approach leads to optimal assignment of the available resources to meet infrastructure requirements. The construction cost and the risk of seismic consequences are considered as the value components. FEMA-P58 methodology is utilized in estimation of the seismic consequences including the repair cost, repair time, injuries and casualties. Endurance Time method is... 

    Layer of Protection Analysis (LOPA) for Nitroglycerine Production

    , M.Sc. Thesis Sharif University of Technology Shojaei, Saeed (Author) ; Rashtchian, Davood (Supervisor)
    Abstract
    Nitroglycerine is an oily liquid and in pure form it is colorless. It is the main component of high explosives such as dynamites, and an essential ingredient of smokeless, double base propellants. The production of nitroglycerine has to solve the problems that arise from the extremely high mechanical sensitivity of the substance and the chemical instability of impure materials. Without sufficient control and mitigation of hazards, incidents have led to severe consequences, such as explosions, and threats to human lives, properties, and the environment. In this study, the hazard and operability study method is used to identify the existing hazards in the nitroglycerine production plant. Then,... 

    Multi-Objective Optimization of Drilling Operation and Formation Damage

    , M.Sc. Thesis Sharif University of Technology Azinpour, Behrouz (Author) ; Jamshidi, Saeed (Supervisor)
    Abstract
    Drilling operation is one of the most important parts of oil production procedure. Therefore, drilling optimization has an effective role in ultimate benefits and total cost reduction. Also formation damage can affect reservoir performance. In this study, a combination of optimization methods for each part of drilling operation has been used and fitness function of total cost is presented. This function includes number of bit runs, bit selection, controllable parameters and drilling mud properties. For prediction of formation damage radius and variable risk analysis, two new methods are proposed and have been used as fitness functions. Finally, by suggesting a multi objective optimization... 

    Quantitative Rsk Assessment and Accident Frequency Determination Based on Fuzzy Logic with Shazand Oil Refinery Accident Case Study

    , M.Sc. Thesis Sharif University of Technology Javidi, Majid (Author) ; Rashtchian, Davoud (Supervisor)
    Abstract
    Today, Quantitative Risk Assessment (QRA) has become an efficient tool in decision making for safety and process experts. To assess the risk of any accident scenario, it is necessary that the probability of that event be determined in addition to estimating the probable consequences. Event tree and fault tree analysis are known to be the standard tools for calculating the frequency of incident outcomes.
    In this research, a new method based on Markov chin and Fuzzy theory is presented to estimate the occurrence probability of events. A one of important parameter which has sufficient effect on probability of incident frequency, is inspection and maintenance interval. in this research... 

    Risk Management in Projects by Bayesian Belief Networks

    , M.Sc. Thesis Sharif University of Technology Chitgar, Siamak (Author) ; Haji, Alireza (Supervisor)
    Abstract
    Risk management is one of the important phases of a project life cycle. There are several quantitative and qualitative methods to determine and plan the proper reaction risks in a project. These methods aim to prevent additional and unnecessary costs. Project managers, stake holders and beneficiaries always believe that risk management of project engineering as one of the importance parts. Although there are multiple methods that can evaluate risk, but there is still research problems especially for risk qualitative and quantitative prediction. This gets more serious after evaluating and minimizing risks effects considering the other risks’ damaging effects which have not been considered. In... 

    A Framework for Seismic Risk Assessment of Electrical Substation Equipment with Reliability and Endurance Time Methods

    , M.Sc. Thesis Sharif University of Technology Ghahremani Baghmisheh, Amir (Author) ; Esmaeil Purestekanchi, Homayoon (Supervisor)
    Abstract
    Influences of dynmic interaction between substation equipment on responses and fragility are studied. Proposing a framework for seismic risk analysis of substation equipment using reliability and endurance time methods is another aim of this project. Risk, in this contex, means the probability of exceeding monetary loss. Three dimensional models of four vulnerable types of equipment including surge arrester, current transformer, circuit breaker and disconnect switch are developed and verified. Six different systems of equipment connected through rigid bus bars comprising of two, three and four equipment are considered. Fragility curves are developed for equipment in both unconnected and... 

    Application of Quantitative Risk Assessment to Site and Layout Process Plants

    , Ph.D. Dissertation Sharif University of Technology Badri, Naser (Author) ; Rashtchian, Davod (Supervisor) ; Nourai, Farshad (Co-Advisor) ; Narimannejad, Alireza (Co-Advisor)
    Abstract
    Plant layout and siting are the earliest steps in any process design that may have significant effects on the further required level of safety and costs. Extensive carried out studies have been published in literatures in which, the safety factor has been taken into account in the form of prediction the severity of likely accidents. Majority of these studies are based on the accident consequence and other important parameters such as the accident frequency and the density of vulnerable items have been ignored. This recent negligence may lead to over conservative designs. To eliminate this recent deficiency, quantitative risk assessment (QRA) is the best procedure than can be suggested.... 

    An Artificial Neural Network Surrogate Model Development for GAGD Process

    , M.Sc. Thesis Sharif University of Technology Rafiee, Javad (Author) ; Pishvaie, Mahmoud Reza (Supervisor) ; Jamshidi, Saeed (Supervisor)
    Abstract
    Gas-Assisted-Gravity-Drainage (GAGD) is a new enhanced oil recovery method which utilizes the natural tendency of gas and oil to segregate due to gravity. Higher recovery of GAGD, compared to continuous gas injection (CGI) and Water-Alternating-Gas (WAG) makes it the focus of researches in recent years. This work is trying to propose a surrogate model based on Artificial Neural Networks for GAGD process. The proposed model should be able to mimic the behavior the process in a short time in order to be used as an alternative computationally expensive simulator where a large number of simulations are needed, such as sensitivity analysis, optimization of the process, or risk analysis. A... 

    Seismic Risk Analysis Considering Soil-Structure Interaction

    , M.Sc. Thesis Sharif University of Technology Khosravikia, Farid (Author) ; Ghannad, Mohammad Ali (Supervisor) ; Mahsouli, Mojtaba (Supervisor)
    Abstract
    The primary objective of this thesis is twofold: First, the effect of soil-structure interaction (SSI) and SSI seismic design provisions on the seismic risk estimates of buildings are studied. Risk, in this context, denotes the probability distribution of seismic monetary loss due to structural and non-structural damage. The risk analysis here uncovers the probability that SSI is beneficial, detrimental, or ineffective on seismic losses. Moreover, the consequence of practicing SSI provisions of current seismic codes on the seismic risk of structures is investigated. Second, the consequences of practicing the SSI provisions of two prominent seismic design guidelines, i.e., ASCE 7-10 and the... 

    Probabilistic Modeling of the Economic Impact of Earthquakes at the Regional Level

    , M.Sc. Thesis Sharif University of Technology Pakizeh, Amir Hossein (Author) ; Haj Kazem Kashani, Hamed (Supervisor)
    Abstract
    Earthquakes can cause significant economic damage to society. These damages include direct economic damage, ie, the cost incurred by the community to rebuild damaged infrastructure. In addition, damaging the infrastructure, the earthquake reduces the level of infrastructure service, and thus, disrupts the businesses that rely on it. The consequences of such disruptions, such as a decline in the level of productivity and efficiency of firms, or an increase in the rate of unemployment and migration from the community, can cause indirect economic damage to society. The costs incurred to society by disasters can be reduced by adopting appropriate solutions. In many cases, however, the incentives... 

    A multivariable approach for estimation of vapor cloud explosion frequencies for independent congested spaces to be used in occupied building risk assessment

    , Article Process Safety and Environmental Protection ; Volume 91, Issue 1-2 , 2013 , Pages 19-30 ; 09575820 (ISSN) Badri, N ; Nourai, F ; Rashtchian, D ; Sharif University of Technology
    2013
    Abstract
    API Recommended Practice 752 is one of the most referenced practices for evaluating vapor cloud explosion (VCE) impacts to site occupied buildings. This reference introduces generic VCE frequencies for different types of process units that are based on VCE incidents database. Although these reported VCE frequencies are not capable of illustrating all parameters that affect explosion likelihood, they are widely used in risk analysis studies and software packages. This paper delineates the structure of a more realistic method for estimation of local VCE frequencies for independent congested spaces or units as a function of process, site, and meteorological variables. Compared to traditional...