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shafiee-jood--majid
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A system dynamics model for improving flood control operation policies
, Article World Environmental and Water Resources Congress 2012: Crossing Boundaries, Proceedings of the 2012 Congress ; 2012 , Pages 962-972 ; 9780784412312 (ISBN) ; Dashti, M ; Abrishamchi, A ; Sharif University of Technology
ASCE
2012
Abstract
The inherent complexities of multi-reservoir flood control systems and their operation conditions along with the improvements of optimization methods have led to a positive trend on better development of these models. This trend tends to provide the operators of these systems with more practical solutions. Although optimization models can provide appropriate solutions for operation of multi-reservoir systems, the exact implementation of these solutions in real world is not guaranteed. This arises mainly due to high level risk of flood situation, real time operation constraints, high level uncertainties of inflows that usually are overlooked in optimization models, and so on. These problems...
Developing An Integrated System Dynamics - Genetic Algorithm Model: Application to Rainfall-Runoff Modelling
, M.Sc. Thesis Sharif University of Technology ; Abrishamchi, Ahmad (Supervisor)
Abstract
Continuous increase in population which leads to increase in water demand, negative ecological and environmental impacts of dam constructions for supplying water, surface and groundwater pollution and climate change impacts on water cycle are among the major reasons that has made water supply into a crisis specifically in the past two decades. This issue is highlighted in regions with arid or semi-arid climatic conditions. Water demand is the key stimulus in the complex and dynamic water resources system which causes interaction among economical, social and environmental sub systems. These issues together with political challenges led to the introduction of integrated water resources...
Monitoring Urmia Lake area variation using MODIS satellite data
, Article World Environmental and Water Resources Congress 2012: Crossing Boundaries, Proceedings of the 2012 Congress ; 2012 , Pages 1917-1926 ; 9780784412312 (ISBN) ; Ahmadalipour, A ; Shafiee Jood, M ; Tajrishy, M ; Abrishamchi, A ; Environ. Water Resour. Inst. (EWRI) Am. Soc. Civ. Eng ; Sharif University of Technology
ASCE
2012
Abstract
Urmia Lake is a large hyper-saline lake located in the northwest of Iran. It plays an important role in the hydrology, climate and ecology of its surrounding regions. In recent years, the water level of Urmia Lake has been dropped significantly. This study investigates the seasonal and annual variations of the lake area from 2000 to 2011 using remote sensing data. MODIS imageries of Normalized Differential Vegetation Index (NDVI) were used to extract the water surface area of the lake. Results reveal a significant decline in the lake area during the last past 12 years. Analysis of the seasonal images shows that maximum and minimum areas of Urmia Lake usually occur in winter and autumn,...
Performance evaluation of water resources systems using system dynamics approach: Application to the Aras River Basin, Iran
, Article World Environmental and Water Resources Congress 2012: Crossing Boundaries, Proceedings of the 2012 Congress ; 2012 , Pages 2367-2377 ; 9780784412312 (ISBN) ; Abrishamchi, A ; Sharif University of Technology
ASCE
2012
Abstract
System Dynamics approach is a powerful tool in water resources systems simulation for evaluating proposed plans and policies in development projects. In Aras River basin, existing water resources do not suffice increasing demand in the near future, thus construction of new reservoirs is under study. In this study, system dynamics approach is used to simulate the water resources system of Darehrood sub basin located in eastern part of Aras River basin. Performance indices are used to evaluate the alternative plans and policies.. Reliability, resiliency and vulnerability, the three performance indices used in study, are estimated using maximum value and mean value estimators mentioned in the...
The Effects of Intentional Process Models on Goal Modeling and Process Conformance Checking
, M.Sc. Thesis Sharif University of Technology ; Rafiei, Majid (Supervisor) ; Khedmati, Majid (Supervisor)
Abstract
In recent years, requirement engineering and goal modeling have gained more attention among different organisations. Therefore, different methods have been designed to discover stakeholders’ requirements and translate them into process and organizational goals. Various goal models have been introduced to represent these goals and their relations towards each other. Still, these methods are manual representations of different process scenarios and do not relate to the actual behavior. In 2014, Map Miner Method (MMM) was introduced to discover intentional process models from event logs. MMM uses Hidden Markov Model (HMM) as a means to represent the process as a map model of strategies and...
On a new formulation of microphenomena: Basic principles, stationary fields and beyond
, Article Pramana - Journal of Physics ; Volume 76, Issue 6 , 2011 , Pages 843-873 ; 03044289 (ISSN) ; Sharif University of Technology
2011
Abstract
In a series of essays, beginning with this article, we are going to develop a new formulation of microphenomena based on the principles of reality and causality. The new theory provides us with a new depiction of microphenomena assuming a unified concept of information, matter and energy. So, we suppose that in a definite microphysical context (including other interacting particles), each particle is enfolded by a probability field whose existence is contingent on the existence of the particle, but it can locally affect the physical status of the particle in a context-dependent manner. The dynamics of the whole particle-field system obeys deterministic equations in a manner such that when...
Correction to black hole radiation due to pair annihilation
, Article Progress of Theoretical and Experimental Physics ; Volume 2022, Issue 3 , 2022 ; 20503911 (ISSN) ; Sharif University of Technology
Physical Society of Japan
2022
Abstract
We consider the emission of charged scalar particles from a Schwarzschild black hole. It is shown that these particles can interact with each other through pair annihilation and, as a result, produce photons. These photons make a correction to the spectrum of photons that are directly emitted from the black hole. By solving the field equations using the Wentzel-Kramers-Brillouin approximation, the pair annihilation rate is taken into account for the most probable case, i.e. the first order, and therefore the correction will be of the order of e2. Considering this scenario, we show that most interactions take place near the event horizon of the black hole, yet the number of interactions is...
A Trajectory Recommendation System for Efficient Finding of Passengers
, M.Sc. Thesis Sharif University of Technology ; Khedmati, Majid (Supervisor) ; Rafiee, Majid (Supervisor)
Abstract
Recommending routes to city taxis in order to improve their performance in finding passengers can reduce traffic, pollution and waiting time for passengers, as well as this, increasing the efficiency of taxis can increase their income. In this study, by analyzing trajectory data obtained from 536 taxis in San Francisco over a period of one month, we generated networks of cells, each of which has time-dependent characteristics such as the probability of finding a passenger, the capacity of each cell, or the amount of demand exists is in the cell and the average speed of passing through that cell. also, the connections between these cells in order to make more use of the experiences of taxi...
Improving Artificial Neural Network Predictive Performance Using Panel Data
, M.Sc. Thesis Sharif University of Technology ; Khedmati, Majid (Supervisor) ; Rafiee, Majid (Supervisor)
Abstract
The purpose of the present study is to develop neural network estimation method for hybrid or panel data which have a combination of two cross-sectional and time series structures and because of the features of both structures, their use in different sciences offers many advantages; and the analytical methods for this data structure are also different from other one-dimensional structures, so different and specific regression models are presented for this data structure. However, in the artificial neural network method, modeling the development for this data structure is neglected, so in the present study, using the concepts of panel regression methods and their application to the...
Investigating the impacts of plug-in hybrid electric vehicles on power distribution systems
, Article IEEE Transactions on Smart Grid ; Volume 4, Issue 3 , 2013 , Pages 1351-1360 ; 19493053 (ISSN) ; Fotuhi Firuzabad, M ; Rastegar, M
2013
Abstract
Despite the economic and environmental advantages of plug-in hybrid electric vehicles (PHEVs), the increased utilization of PHEVs brings up new concerns for power distribution system decision makers. Impacts of PHEVs on distribution networks, although have been proven to be noticeable, have not been thoroughly investigated for future years. In this paper, a comprehensive model is proposed to study the PHEV impacts on residential distribution systems. In so doing, PHEV fundamental characteristics, i.e., PHEV battery capacity, PHEV state of charge (SOC), and PHEV energy consumption in daily trips, are accurately modeled. As some of these effective characteristics depend on vehicle owner's...
Comparison between decoherence time for a two-state spin 1/2 system with its corresponding quantum retrieval period
, Article Central European Journal of Physics ; Volume 9, Issue 6 , 2011 , Pages 1410-1420 ; 18951082 (ISSN) ; Tirandaz, A ; Sharif University of Technology
2011
Abstract
The evolution of a two-state quantum system (a spin 1/2 particle) in both the framework of standard quantum mechanics and under the decoherence regime is considered. The former approach on this issue is the well-known quantum flipping process of a dichotomic system subjected to a time-dependent magnetic field. In the latter approach, the Spin-Boson model is utilized to describe the interaction of system with its environment and the Born-Markov master equation is derived to obtain the decoherence time. It is possible to show that under certain conditions, one may find a potential conflict between the predictions of decoherence theory and the result observed in a typical quantum flipping...
Investigation of barrier properties of poly(ethylene vinyl acetate)/organociay nanocomposite films prepared by phase inversion method
, Article Macromolecular Symposia ; Volume 274, Issue 1 , 2008 , Pages 1-5 ; 10221360 (ISSN) ; Ramazani, A ; Sharif University of Technology
2008
Abstract
In this research work, to reduce permeability of polyethylene vinyl acetate) packaging films, organoclay nanocomposites of these thermoplastics were prepared by solution method. Organoclay are mixed with polyethylene vinyl acetate (EVA) with 18 and 28% of vinyl acetate (VA) content in solution phase. Solutions of 3, 5 and 7% of organoclay are prepared under reflux condition and then nanocomposite films are prepared by thermal phase inversion method. Morphological and gas barrier properties of different prepared samples have been investigated. Morphology of prepared nanocomposite films and order of exfoliation of clay were investigated using X-ray diffraction (XRD) and transmission electron...
On the relationship between entropy and information
, Article Physics Essays ; Volume 20, Issue 3 , 2007 , Pages 487-493 ; 08361398 (ISSN) ; Karimi, M ; Sharif University of Technology
2007
Abstract
In this paper we analyze the relationship between entropy and information in the context of the mixing process of two identical ideal gases. We will argue that entropy has a special information-based feature that is enfolded in the statistical entropy, but the second law does not include it directly. Therefore, in some given processes in thermodynamics where there is no matter and energy interaction between the system and the environment, the state of the system may go toward a situation of lower probability to increase the observer's information about the environment. This is a kind of information-based interaction in which the total entropy is not constrained by the second law
On the relevance of fair sampling assumption in the recent bell photonic experiments
, Article Journal of Modern Optics ; Volume 52, Issue 10 , 2005 , Pages 1405-1414 ; 09500340 (ISSN) ; Golshani, M ; Sharif University of Technology
2005
Abstract
In the experimental verification of Bell's inequalities in real photonic experiments, it is generally believed that the so-called fair sampling assumption (which means that a small fraction of results provide a fair statistical sample) has an unavoidable role. Here, we want to show that the interpretation of these experiments could be feasible, if some different alternative assumptions other than the fair sampling were used. For this purpose, we derive an efficient Bell-type inequality which is a CHSH-type inequality in real experiments. Quantum mechanics violates our proposed inequality, independent of the detection-efficiency problems. © 2005 Taylor & Francis Group Ltd
Complete correlation, detection loophole and Bell's theorem
, Article Fortschritte der Physik ; Volume 53, Issue 1 , 2005 , Pages 105-113 ; 00158208 (ISSN) ; Golshani, M ; Sharif University of Technology
2005
Abstract
Two new formulations of Bell's theorem are given here. First, we consider a definite set of two entangled photons with only two polarization directions, for which Bell's locality assumption is violated for the case of perfect correlation. Then, using a different approach, we prove an efficient Bell-type inequality which is violated by some quantum mechanical predictions, independent of the efficiency factors. © 2005 WILEY-VCH Verlag GmbH & Co, KGaA, Weinheim
The Role and Significance of the Concept of Information in Physical Phenomena
, Ph.D. Dissertation Sharif University of Technology ; Shafiee, Afshin (Supervisor)
Abstract
Undoubtedly, the concept of information has an outstanding role in our description of physical systems and biological processes. In the framework of pragmatic approach, information is a useful notion through which any physical event gets its significance. In this approach, information can be understood and recognized while it is capable of producing new information. Thus, the meaning of information depends on our recognition and understanding as conscious beings. Accordingly, the following question may arise: where is the role of conscious being in the emergence of physical properties in Nature? To answer this fundamental question, we first investigate how information enters the physics, in...
The Study of Chemistry in Space and Its Realtionship with Origin of Life
, M.Sc. Thesis Sharif University of Technology ; Shafiee, Afshin (Supervisor)
Abstract
In this study the concept of the origin of life, as an important question, is investigated and reviewed.Then the possibility of the beginning of life from an extraterrestrial origin is studied via spectroscopy methods to analyze the role of the cosmic waves.Moreover, by considering the similarity between the chirality of the essential amino acids and extraterrestrial amino acids, found in meteors the various methods for studying the structure of molecules, as well as the possibility of the transfer of the central elements of life from space to the earth are reviewed in details.Finally, we suggest how chirality might be emerged due to the interaction of the molecule with the environment,...
Experimental Study of Microbubbles Generation as a Contrast Agent in Blood, to Determine the Blood Flow by Echo-PIV Method
, M.Sc. Thesis Sharif University of Technology ; Shafiee, Behshad (Supervisor)
Abstract
Today microbubbles are broadly used as ultrasound contrast agents. These bubbles enhance the image resolution of B-mode pictures. Flow focusing in microchannels could provide us the goal of one-size bubbles generation. Microbubbles could use as tracers in Echo_PIV method to determine the velocity profile in main body vessels such as carotid. In this paper we introduce a new production method to fabricate a low-cost microchannel for preparing Microbubble contrast agents (less than 50 microns) by using some surface active agents and a viscosity enhancing material to obtain appropriate Microbubbles with desired life time and stability for any in vitro infusion for velocity measurement. By...
On Proposing New Thought Experiments in Quantum Domain
,
Ph.D. Dissertation
Sharif University of Technology
;
Shafiee, Afshin
(Supervisor)
Abstract
Although quantum mechanics has thrilled a multitude of successes since its birth, it has also generated puzzles that persist to this day. These puzzles are largely connected with the role of measurement in quantum mechanics. Therefore, we are dealing with individual phenomena and that our possibilities of handling the measuring instruments allow us only to make a choice between the different complementary types of phenomena. Within the framework of delayed-choice experiments, the choice between complementary types of phenomena is postponed to the moments after the preparation of system is a superposition state. Regarding the probability theory, we have concluded that the delayed-choice...
Adaptive Estimation of Components of a Three-Phase Signal Polluted with Sinusoidal Disturbance
, M.Sc. Thesis Sharif University of Technology ; Karimi, Houshang (Supervisor)
Abstract
This thesis proposes a new method for estimation of parameters of a multi-component signal. The signal is composed of several sinusoidal components whose frequencies and magnitudes are unknown. Moreover, the signal is polluted with white noise. The estimated parameters are frequency, amplitude, and phase-angle of each component. The proposed method is able to adaptively decompose the multi-component signal into its constituting sinusoidal components. The core unit of the proposed method comprises an adaptive band-pass and an adaptive notch filter. The proposed method consists of parallel connection of several core units. The band pass filter rejects all components except the one whose...