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    Continuous monitoring of safety performance

    , Article Total Safety and the Productivity Challenge ; 2019 , Pages 126-140 ; 9781351609074 (ISBN); 9781138091306 (ISBN) Amir-Heidari, P ; Sharif University of Technology
    Taylor and Francis  2019
    Abstract
    Key performance indicators (KPIs) are the fundamental building blocks in measuring and monitoring processes of safety management. This chapter describes a classification of safety KPIs and a review of literature leads to a new framework. It aims to develop a logical selection and aggregation methodology for generating a single number that reflects safety performance. Determining a mechanism for performance measurement and monitoring is a key part of any management system, and this has a higher importance for total safety management. Personal safety deals with the prevention of occupational accidents that usually have low severities and high frequencies. The measurement of safety has been... 

    Continuous monitoring of safety performance

    , Article Total Safety and the Productivity Challenge ; 2019 , Pages 126-140 ; 9781351609074 (ISBN); 9781138091306 (ISBN) Amir Heidari, P ; Sharif University of Technology
    Taylor and Francis  2019
    Abstract
    Key performance indicators (KPIs) are the fundamental building blocks in measuring and monitoring processes of safety management. This chapter describes a classification of safety KPIs and a review of literature leads to a new framework. It aims to develop a logical selection and aggregation methodology for generating a single number that reflects safety performance. Determining a mechanism for performance measurement and monitoring is a key part of any management system, and this has a higher importance for total safety management. Personal safety deals with the prevention of occupational accidents that usually have low severities and high frequencies. The measurement of safety has been... 

    Probabilistic risk assessment of oil spill from offshore oil wells in Persian Gulf

    , Article Marine Pollution Bulletin ; Volume 136 , 2018 , Pages 291-299 ; 0025326X (ISSN) Amir Heidari, P ; Raie, M ; Sharif University of Technology
    2018
    Abstract
    Oil spills in the marine environment can have serious environmental, social and economic impacts. These impacts may be of transnational nature, and this makes the oil spill problem an international issue. Therefore, it is necessary to develop a common structured methodology for oil spill risk assessment. In this research, a general framework is presented for probabilistic risk assessment of oil spill from offshore oil wells. A case study is also performed in Persian Gulf to quantify the risk posed by 357 offshore wells to the near-shore receptors. First, thousands of hypothetical spill scenarios of different volumes are defined and simulated using a Lagrangian particle tracking model. Then,... 

    A new stochastic oil spill risk assessment model for Persian Gulf: Development, application and evaluation

    , Article Marine Pollution Bulletin ; Volume 145 , 2019 , Pages 357-369 ; 0025326X (ISSN) Amir Heidari, P ; Raie, M ; Sharif University of Technology
    Elsevier Ltd  2019
    Abstract
    Persian Gulf is a semi-enclosed highly saline reverse estuary that is exposed to the risk of oil spills in offshore oil and gas activities. In the early 2000s, a specific version of NOAA's Trajectory Analysis Planner (TAP II) was developed for Persian Gulf to assist regional organizations in preparing oil spill contingency plans. In this research, a new stochastic model is developed to cover the limitations of TAP II. The new model is based on an advanced trajectory model, which is now linked with high resolution spatiotemporal data of the wind and sea current. In a case study, the developed model is compared with TAP II, and evaluated by multiple tests designed for analysis of uncertainty,... 

    Response planning for accidental oil spills in persian gulf: a decision support system (DSS) based on consequence modeling

    , Article Marine Pollution Bulletin ; Volume 140 , 2019 , Pages 116-128 ; 0025326X (ISSN) Amir Heidari, P ; Raie, M ; Sharif University of Technology
    Elsevier Ltd  2019
    Abstract
    Different causes lead to accidental oil spills from fixed and mobile sources in the marine environment. Therefore, it is essential to have a systematic plan for mitigating oil spill consequences. In this research, a general DSS is proposed for passive and active response planning in Persian Gulf, before and after a spill. The DSS is based on NOAA's advanced oil spill model (GNOME), which is now linked with credible met-ocean datasets of CMEMS and ECMWF. The developed open-source tool converts the results of the Lagrangian oil spill model to quantitative parameters such as mean concentration and time of impact of oil. Using them, two new parameters, emergency response priority number (ERPN)... 

    Consequence Modelling and Probabilistic Risk Assessment of Oil Spills in the Marine Waters

    , Ph.D. Dissertation Sharif University of Technology Amir Heidari, Payam (Author) ; Raie, Mohammad (Supervisor)
    Abstract
    Different causes in the exploration, production and transport of oil in the marine environment result in oil spill events. Since elimination of the probability of occurrence of spills is not possible, it is important to have a plan to control the risk of oil spills by optimal response. In this research, a general stucture is presented for the DSS required for oil spill response planning. This system can be used for evaluation of the effectiveness of response drills, and risk-based ranking of receptor areas and spill sources. Ranking based on risk is realized through probabilistic or stochastic risk assessment. The applicability of the proposed system is examined in differnet case studies in... 

    An Efficient Approach for Improving the Performance of Real-time Flow Routing in SDN Controllers

    , M.Sc. Thesis Sharif University of Technology Heidari, Hossein (Author) ; Jahangir, Amir Hossein (Supervisor)
    Abstract
    In real-time systems, jobs that miss their deadline are considered worthless or ineffective. Nowadays, real-time applications (such as multimedia) that communicate through software-defined networks (SDN) are widely used and will continue to expand in the future. SDN is an emerging network architecture in which control plane is separated from data plane to manage it directly. In this research, we make changes to the controller and the switch used in such network to deliver real time packets or real-time flows (such as video) on time, as much as possible. As missed deadline packets are worthless and they waste bandwidth, dropping them is a solution. Moreover, the controller can drop flows that... 

    Automatic Well Planning to Optimize ROP Using Previous Wells Data

    , M.Sc. Thesis Sharif University of Technology Heidari, Amir Hossein (Author) ; Jamshidi, Saeed (Supervisor)
    Abstract
    Today, with the reduction of world oil prices and the development of competing energy sources, fossil fuels such as nuclear energy, electricity, wind, etc., in order to increase the economic efficiency of oil sales, we must Reduce production costs to a minimum. If the components of oil extraction costs are examined, the cost of drilling production wells is one of the main economic components that affect the cost of producing oil. Therefore, according to the above explanations, the cost of drilling wells should be reduced.To reduce the cost of drilling a well to be drilled, it is better to predict the drilling parameters (for example ROP) before starting the drilling process. For this... 

    Phase Identification and Balancing in LV Distribution Networks Using Smart Meters Data

    , M.Sc. Thesis Sharif University of Technology Heidari Akhijahani, Adel (Author) ; Safdarian, Amir (Supervisor)
    Abstract
    With the rapid proliferation of residential rooftop photovoltaic (PV) systems, current and voltage unbalance issues have become a matter of great concern in low voltage (LV) distribution feeders. This, however, necessitates identification of the hosting phase of the connected single-phase customers and PV panels. Both of the challenges have been addressed in this thesis. In the first place, this thesis proposes a mixed integer linear programming (MILP) model for phase identification problem. The model considers potential error in the input data provided by smart meters. To mitigate negative impacts of the error, the data associated with several consecutive time intervals are taken into... 

    Design, Thermodynamic and Economic Evaluation of a Solar Assisted Air Conditioning System for Energy and Carbon Saving

    , M.Sc. Thesis Sharif University of Technology Heidari, Amir Reza (Author) ; Roshandel, Ramin (Supervisor) ; Vakiloroaya, Vahid (Supervisor)
    Abstract
    Evaporative cooling systems are of most common cooling systems which their electricity consumption is much lower than vapor compression cooling systems. Enhancement of these system’s performance could help to propagate these systems and also decrease the electricity consumption and corresponding emissions in large scale. In this thesis, first a modified cycle is proposed for evaporative cooling. Then, in order to use evaporative cooling in humid climates, a desiccant wheel is implemented in this modified evaporative cooler. As using evaporative cooling will cause high water consumption, a novel cycle is proposed for desiccant based evaporative cooling which is able to cover system water... 

    Optimization on TDOA-Based Localization and its Feasibility Study

    , Ph.D. Dissertation Sharif University of Technology Heidari, Vahid (Author) ; Haj Sadeghi, Khosrow (Supervisor) ; Pezeshk, Amir Mansour (Co-Advisor)
    Abstract
    In this thesis, the problem of locating a source based on the time difference of arrival (TDOA) has been studied and three different methods have been presented to improve the precision of the positioning. The first method is a solution to the least square error (LSE) by utilizing a convex problem. Generally, the mentioned problem is a non-convex problem; however, it is possible to convert it to a convex one by some relaxation in the constraints. By some justifiable and insightful relaxation, not only we obtain a convex problem, but also the exact solution of the main problem is derived. The second method is using high perturbed TDOA measurements which severely affected the localization.... 

    Design and Fabrication of an Integrated Lab-on-a-chip System for DNA Extraction from Cells and Gene Amplification

    , M.Sc. Thesis Sharif University of Technology Topa Heidari, Mohammad Mahdi (Author) ; Shamloo, Amir (Supervisor) ; Nouri Borujerdi, Ali (Supervisor)
    Abstract
    In this study, an integrated lab-on-a-chip (LOC) system was designed and developed to perform various processes, including cell separation, cell lysis, DNA extraction, and amplification, in an automated and unified manner. The system was designed to operate with fully disposable components, eliminating the risk of cross-contamination. The design includes five distinct microfluidic chips, each dedicated to a specific function. For cell separation, the inertial method was employed, which operates without the need for a micromixer and delivers high accuracy. Simulations demonstrated a recovery rate of 100% and a purity of 96.8%, while experimental results showed a recovery rate of 88.8% and a... 

    A state-of-the-art model for spatial and stochastic oil spill risk assessment: A case study of oil spill from a shipwreck

    , Article Environment International ; Volume 126 , 2019 , Pages 309-320 ; 01604120 (ISSN) Amir Heidari, P ; Arneborg, L ; Lindgren, J. F ; Lindhe, A ; Rosén, L ; Raie, M ; Axell, L ; Hassellöv, I. M ; Sharif University of Technology
    Elsevier Ltd  2019
    Abstract
    Oil spills are serious environmental issues that potentially can cause adverse effects on marine ecosystems. In some marine areas, like the Baltic Sea, there is a large number of wrecks from the first half of the 20th century, and recent monitoring and field work have revealed release of oil from some of these wrecks. The risk posed by a wreck is governed by its condition, hazardous substances contained in the wreck and the state of the surrounding environment. Therefore, there is a need for a common standard method for estimating the risks associated with different wrecks. In this work a state-of-the-art model is presented for spatial and stochastic risk assessment of oil spills from... 

    Temperature-dependent multi-scale modeling of surface effects on nano-materials

    , Article Mechanics of Materials ; Volume 46 , March , 2012 , PP. 94–112 Khoei, A. R. (Amir Reza) ; Ghahremani, P ; Sharif University of Technology
    2012
    Abstract
    In this paper, a novel temperature-dependent multi-scale method is developed to investigate the role of temperature on surface effects in the analysis of nano-scale materials. In order to evaluate the temperature effect in the micro-scale (atomic) level, the temperature related Cauchy–Born hypothesis is implemented by employing the Helmholtz free energy, as the energy density of equivalent continua relating to the inter-atomic potential. The multi-scale technique is applied in atomistic level (nano-scale) to exhibit the temperature related characteristics. The first Piola–Kirchhoff stress and tangential stiffness tensor are computed, as the first and second derivatives of the free energy... 

    A general model for I/O system theory, Proceedings of AIMC31 [electronic resource]

    , Article Iranian Journal of Fuzzy Systems ; 2006, Volume 3, Issue 2, Page 1-19 Daneshgar, A. (Amir) ; Hashem, Amir ; Sharif University of Technology

    Universal image steganalysis using singular values of DCT coefficients

    , Article 2013 10th International ISC Conference on Information Security and Cryptology ; 2013 Heidari, M ; Gaemmaghami, S ; Sharif University of Technology
    IEEE Computer Society  2013
    Abstract
    We propose a blind image steganalysis method based on the Singular Value Decomposition (SVD) of the Discrete Cosine Transform (DCT) coefficients that are revisited in this work. We compute geometric mean, mean of log values, and statistical moments (mean, variance and skewness) of the SVDs of the DCT sub-blocks that are averaged over the whole image to construct a 480-element feature vector for steganalysis. These features are fed to a Support Vector Machine (SVM) classifier to discriminate between stego and cover images. Experimental results show that the proposed method outperforms most powerful steganalyzers when applied to some well-known steganography algorithms  

    Intelligent clustering in wireless sensor networks

    , Article 1st International Conference on Networks and Communications, NetCoM 2009, 27 December 2009 through 29 December 2009, Chennai ; 2009 , Pages 12-17 ; 9780769539249 (ISBN) Heidari, E ; Movaghar, A ; Sharif University of Technology
    2009
    Abstract
    Minimization of the number of cluster heads in a wireless sensor network is a very important problem to reduce channel contention and to improve the efficiency of the algorithm when executed at the level of cluster-heads. In this paper, we propose an efficient method based on genetic algorithms (GAs) to solve a sensor network optimization problem. Long communication distances between sensors and a sink in a sensor network can greatly drain the energy of sensors and reduce the lifetime of a network. By clustering a sensor network into a number of independent clusters using a GA, we can greatly minimize the total communication distance, thus prolonging the network lifetime. Simulation results... 

    The effect of rippled graphene sheet roughness on the adhesive characteristics of a collagen-graphene system

    , Article International Journal of Adhesion and Adhesives ; Volume 64 , 2016 , Pages 9-14 ; 01437496 (ISSN) Heidari, H ; Shamloo, A ; Sharif University of Technology
    Elsevier Ltd  2016
    Abstract
    A great amount of effort has been made in order to reach a more precise understanding of the adhesion phenomenon that happens as a vital component of several biological systems. Therefore, a firm understanding of the important factors that influence this phenomenon is of special importance in triggering the adhesive characteristics of different biological, bio-inspired and synthetic materials in fields such as tissue engineering. In this study the adhesive characteristics of a multi-material system consisting of the frequently used synthetic material, graphene, in the form of armchair-configuration sheets, and an important biological filament which is type 1 Collagen consisting of 3 alpha... 

    Using makeup water to recycle cooling tower evaporated water: A feasibility study using experimental data

    , Article International Journal of Energy Technology and Policy ; Volume 17, Issue 3 , 2021 , Pages 227-238 ; 14728923 (ISSN) Heidari, A ; Heidari, E ; Sharif University of Technology
    Inderscience Publishers  2021
    Abstract
    Wet cooling towers are one of the most water-intensive technologies, which are widely used in air conditioning applications, especially in dry regions. Considering the current water crisis around the world, it is essential to improve the design of these cooling towers to reduce their water consumption, while maintaining their cooling performance. Makeup water of cooling tower is usually a constant-temperature water which is cold enough to condensate the moisture content of the cooling tower exhaust air. Therefore, it has great potential to recycle water evaporation of cooling towers, which is not considered so far. This paper investigates a novel design for cooling towers utilising the... 

    Project Finance and Motivations and Optimum Approach of Using it in LNG Industry of Iran

    , M.Sc. Thesis Sharif University of Technology Heidari, Mahdi (Author) ; Zamani, Shiva (Supervisor)
    Abstract
    Project Finance is a novel approach in financing big projects. High debt ratio, independency to promoter credit and establishing a special purpose company, are some of project finance characteristics that could be very beneficial in some projects. Liquid Natural Gas (LNG) is a solution for exporting natural gas to far destination. As economical and environmental benefits of using natural gas have been increased in recent years, LNG industry has been experienced rapid growth. In this project we analyze project finance and then describe economical motivation of using this method in LNG industry of Iran.