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Future Studies of Sustainability Indicators of Iranian Supply Energy System
, M.Sc. Thesis Sharif University of Technology ; Maleki, Abbas (Supervisor)
Abstract
According to current trend of energy production and consumption in the world, economic problems in various countries and too many eco-system disorders in which created by an unsustainable trend in development, recently, the concept of “sustainability” and in the following “sustainable development” has been featured by scientists, researchers and policy makers in different scientific disciplines specially energy system engineering. Therefore exact recognition of unsustainability of local and global energy supply and demand system is very essential. In this research after selection of five energy indicators for sustainable development by Delphi and MCDM methods, future perspective of Iranian...
Evaluating the effect of non-poisson traffic patterns on power consumption of sleep mode in the IEEE 802.16e MAC
, Article 4th IEEE and IFIP International Conference on Wireless and Optical Communications Networks, WOCN 2007, Singapore, 2 July 2007 through 4 July 2007 ; 2007 ; 1424410045 (ISBN); 9781424410040 (ISBN) ; Nayebi, M. M ; Sharif University of Technology
2007
Abstract
In this paper, we study the effect of non-Poisson traffic patterns on energy consumption for IEEE 802.16e nodes while operating in the sleep mode. In the sleep mode, a Mobile Subscribe Station (MSS) sleeps for a sleep interval and wakes up at the end of this interval in order to check buffered packet(s) at Base Station (BS) destined to it. If there is no packet, the MSS increases the sleep window up to the maximum value and sleeps again. For a more general traffic pattern (rather than Poisson), we evaluate the average power consumption. Based on our analysis, we conclude that traffic pattern plays an important role in power consumption. ©2007 IEEE
Effect of different traffic patterns on power consumption of sleep mode in the IEEE 802.16e MAC
, Article 2007 IEEE International Conference on Telecommunications and Malaysia International Conference on Communications, ICT-MICC 2007, Penang, 14 May 2007 through 17 May 2007 ; February , 2007 , Pages 649-653 ; 1424410940 (ISBN); 9781424410941 (ISBN) ; Nayebi, M. M ; Ashtiani, F ; Sharif University of Technology
2007
Abstract
In this paper, we study the effect of some traffic patterns on energy consumption for IEEE 802.16e nodes while operating in the sleep mode. In the sleep mode, a Mobile Subscribe Station (MSS) sleeps for a sleep interval and wakes up at the end of this interval in order to check buffered packet(s) at Base Station (BS) destined to it. If there is no packet, the MSS increases the sleep window up to the maximum value and sleeps again. For a more general traffic pattern, we evaluate the average power consumption. Based on our analysis, we conclude that traffic pattern plays an important role in power consumption. ©2007 IEEE
Estimation of Chitgar Lake Evaporation and the Impact of Chemical Coverings on its Reduction
, M.Sc. Thesis Sharif University of Technology ; Tajrishy, Masoud (Supervisor) ; Irajizad, Azam (Supervisor)
Abstract
Reducing water evaporation is one of the ways to overcome the low precipitation and drought conditions in water reservoirs. For this purpose, extensive studies have been investigated on physical and chemical coatings on lakes and reservoirs. Physical methods often involve the use of floating covers on the water surface to block evaporation by shading, most of which are only suitable for reservoirs with surface areas smaller than 5 hectares. In chemical methods, the evaporation can be decreased by nanomaterial coating, usually, containing long-chain molecules, which by spraying them on the surface, molecular monolayers are formed. In this study, the effect of nanometer coatings on the surface...
Power consumption evaluation of sleep mode in the IEEE 802.16e MAC with multi service connections
, Article 2007 IEEE International Conference on Signal Processing and Communications, ICSPC 2007, Dubai, 14 November 2007 through 27 November 2007 ; 2007 , Pages 1363-1366 ; 9781424412365 (ISBN) ; Nayebi, M. M ; Tadaion, A. A ; Sharif University of Technology
2007
Abstract
In the sleep mode, a Mobile Subscribe Station (MSS) sleeps for a sleep interval and wakes up at the end of this interval in order to check buffered packet(s) at Base Station (BS) destined to it. If there is no packet, the MSS increases the sleep window up to the maximum value or keeps it unchanged and sleeps again. In this paper, we study the effect of presence of multi service connections with different power saving classes (PSCs) on power consumption for IEEE 802.16e nodes while operating in the sleep mode. Using multi service connections may result in overlapping of availability and unavailability intervals and reducing the effectiveness of power saving mode of the subscriber. © 2007 IEEE...
Prediction of natural gas flow through chokes using support vector machine algorithm
, Article Journal of Natural Gas Science and Engineering ; Vol. 18, issue , 2014 , pp. 155-163 ; ISSN: 18755100 ; Kanani, M ; Arabloo, M ; Bahadori, A ; Zendehboudi, S ; Sharif University of Technology
2014
Abstract
In oil and gas fields, it is a common practice to flow liquid and gas mixtures through choke valves. In general, different types of primary valves are employed to control pressure and flow rate when the producing well directs the natural gas to the processing equipment. In this case, the valve normally is affected by elevated levels of flow (or velocity) as well as solid materials suspended in the gas phase (e.g., fine sand and other debris). Both surface and subsurface chokes may be installed to regulate flow rates and to protect the porous medium and surface facilities from unusual pressure instabilities.In this study a reliable, novel, computer based predictive model using Least-Squares...
A novel viewpoint to the green city concept based on vegetation area changes and contributions to healthy days: a case study of Mashhad, Iran
, Article Environmental Science and Pollution Research ; 2021 ; 09441344 (ISSN) ; Makian, M ; Gheibi, M ; Fathollahi Fard, A. M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
One of the significant challenges in urbanization is the air pollution. This highlights the need of the green city concept with reconsideration of houses, factories, and traffic in a green viewpoint. The literature review confirms that this reconsideration for green space has a positive effect on the air quality of large cities and to reduce the air pollution. The purpose of this study is to evaluate the annual vegetation changes in the green space of Mashhad, Iran as a very populated city in the middle east to study the air pollution. To investigate the relationship between the air pollution and vegetation, the Landsat 8 satellite images for summer seasons of 2013–2019 were used to extract...
A novel viewpoint to the green city concept based on vegetation area changes and contributions to healthy days: a case study of Mashhad, Iran
, Article Environmental Science and Pollution Research ; Volume 29, Issue 1 , 2022 , Pages 702-710 ; 09441344 (ISSN) ; Makian, M ; Gheibi, M ; Fathollahi Fard, A. M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
One of the significant challenges in urbanization is the air pollution. This highlights the need of the green city concept with reconsideration of houses, factories, and traffic in a green viewpoint. The literature review confirms that this reconsideration for green space has a positive effect on the air quality of large cities and to reduce the air pollution. The purpose of this study is to evaluate the annual vegetation changes in the green space of Mashhad, Iran as a very populated city in the middle east to study the air pollution. To investigate the relationship between the air pollution and vegetation, the Landsat 8 satellite images for summer seasons of 2013–2019 were used to extract...
Evaporation mitigation assessment by self-assembled nano-thickness films in shallow fresh water lake using fixed and semi-floating pans
, Article Environmental Processes ; Volume 9, Issue 3 , 2022 ; 21987491 (ISSN) ; Mohammadi, M ; Doulabi, M ; Iraji zad, A ; Tajrishy, M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
Controlling evaporation plays an essential role in arid and semi-arid water resources systems where it accounts for a considerable amount of reservoirs outflow. In this study, we have evaluated evaporation reduction efficiency of different kinds of self-assembled nano-thickness films. The films consist of six different combinations of stearyl and cetyl alcohols with additives such as jojoba oil, stearic acid, and calcium hydroxide. The study lasted from July to August and utilized two pairs of class A evaporation pans: one pair was semi-floating on Chitgar lake water surface while the other one was located on the shore. The experimental results showed that a monolayer containing 3:1 stearyl...
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 ; Hashem, Amir ; Sharif University of TechnologyRepurposing the drug, ivermectin, in COVID-19: toxicological points of view
, Article European Journal of Medical Research ; Volume 27, Issue 1 , 2022 ; 09492321 (ISSN) ; Mirzaei, R ; Nakhaee, S ; Nejatian, A ; Ghafari, S ; Mehrpour, O ; Sharif University of Technology
BioMed Central Ltd
2022
Abstract
The global COVID-19 pandemic has affected the world’s population by causing changes in behavior, such as social distancing, masking, restricting people’s movement, and evaluating existing medication as potential therapies. Many pre-existing medications such as tocilizumab, ivermectin, colchicine, interferon, and steroids have been evaluated for being repurposed to use for the treatment of COVID-19. None of these agents have been effective except for steroids and, to a lesser degree, tocilizumab. Ivermectin has been one of the suggested repurposed medications which exhibit an in vitro inhibitory activity on SARS-CoV-2 replication. The most recommended dose of ivermectin for the treatment of...
Experimental and Numerical Study of Spray Combustion under Hot-diluted Conditions
, M.Sc. Thesis Sharif University of Technology ; Mardani, Amir (Supervisor)
Abstract
In this thesis, combustion of liquid fuel spray under the condition of hot and diluted oxidizer, has been investigated. To this end, a novel type laboratory-scale test rig was designed to study the physics governing the MILD-Spray combustion conditions with an applied approach. The underlined test rig eliminates the operational problems of its predecessor test stands and is used for a heavier fuel with much more complex chemical composition (kerosene). The test section is axially symmetrical, in which the fuel is injected by a pressure-swirl atomizer in the direction of hot and diluted co-flowing air. With the use of the aforesaid test rig, the effect of variables such as oxygen...
Residuated semigroups and morphological aspects of translation invariant systems [electronic resource]
, Article 1997, Volume 90, Issue 1, Pages 69–81 ; Fuzzy Sets and Systems ; Sharif University of Technology
Abstract
The main goal of this paper is to verify classical properties of morphological operators within the general model of translation invariant (TI) systems. In this model, TI operators are defined on the space of LG-fuzzy sets Φ i.e. Φ = {A: G → Ω ∪ {− ∞}} in which G is an abelian group and Ω is a complete lattice ordered group. A TI operator Y is an operator on Φ which is invariant under translation on G and Ω as groups. We consider the generalization of Minkowski addition (D on Φ and we emphasize that (Φ,⊛) is an involutive residuated topological monoid. We verify all properties of traditional (set-theoretic) morphological operators as well as classical representations (Matheron, 1967) for...
On defining numbers of circular complete graphs
, Article Discrete Mathematics ; Volume 307, Issue 2, 28 January 2007, Pages 173–180 ; Sharif University of Technology
Abstract
Let d(σ)d(σ) stand for the defining number of the colouring σσ. In this paper we consider View the MathML sourcedmin=minγd(γ) and View the MathML sourcedmax=maxγd(γ) for the onto χχ-colourings γγ of the circular complete graph Kn,dKn,d. In this regard we obtain a lower bound for dmin(Kn,d)dmin(Kn,d) and we also prove that this parameter is asymptotically equal to χ-1χ-1. Also, we show that when χ⩾4χ⩾4 and s≠0s≠0 then dmax(Kχd-s,d)=χ+2s-3dmax(Kχd-s,d)=χ+2s-3, and, moreover, we prove an inequality relating this parameter to the circular chromatic number for any graph G
Duality in a generalized model for translation invariant systems [electronic resource]
, Article Fuzzy Sets and Systems ; 1996, Volume 83, Issue 3, Pages 347–352 ; Sharif University of Technology
Abstract
In a previous paper we introduced a generalized model for translation invariant (TI) operators. In this model we considered the space, φ of all maps from an abelian group G to ω U {-∞}, called LG-fuzzy sets, where ω is a complete lattice-ordered group; and we defined TI operators on this space. Also, in that paper, we proved strong reconstruction theorem to show the consistency of this model. This theorem states that for an order-preserving TI operator Y one can explicitly compute Y(A), for any A, from a specific subset of φ called the base of Y. In this paper duality is considered in the same general framework, and in this regard, continuous TI operators are studied. This kind of operators...
Reconstruction in a generalized model for translation invariant systems [electronic resource]
, Article Fuzzy Sets and Systems ; 1996, Volume 83, Issue 1, Pages 51–55 ; Sharif University of Technology
Abstract
We consider translation invariant (TI) operators on Φ, the set of maps from an abelian group G to Ω ∪ {−∞} , called LG-fuzzy sets, where 0 is a complete lattice ordered group. By defining Minkowski and morphological operations on Φ and considering order preserving operators, we prove a reconstruction theorem. This theorem, which is called the Strong Reconstruction Theorem (SRT), is similar to the Convolution Theorem in the theory of linear and shift invariant systems and states that for an order preserving TI operator Y one can explicitly compute Y ( A ), for any A , from a specific subset of Φ called the base of Y . The introduced framework is a general model for the theory of translation...
General theory of translation invariant systems [electronic resource]
, Article Mathematics and Its Applications ; Volume 329, 1995, pp 77-89 ; Sharif University of Technology
Abstract
The basic goal of this article is to present an abstract system-theoretic approach to morphological filtering and the theory of translation invariant systems which is mainly based on residuated semigroups. Some new results as well as a number of basic questions are also introduced
Forcing structures and cliques in uniquely vertex colorable graphs [electronic resource]
, Article SIAM Journal on Discrete Mathematics ; 2001, Volume 14, Issue 4, Pages 433-445 ; Sharif University of Technology
Abstract
Let G be a simple undirected uniquely vertex k-colorable graph, or a k-UCG for short. M. Truszczyński [Some results on uniquely colorable graphs, in Finite and Infinite Sets, North-Holland, Amsterdam, 1984, pp. 733--748] introduced $e^{^{*}}(G)=|V(G)|(k-1)-{k \choose 2}$ as the minimum number of edges for a k-UCG and S. J. Xu [J. Combin. Theory Ser. B, 50 (1990), pp. 319--320] conjectured that any minimal k-UCG contains a Kk as a subgraph. In this paper, first we introduce a technique called forcing. Then by applying this technique in conjunction with a feedback structure we construct a k-UCG with clique number k-t, for each $t \geq 1$ and each k, when k is large enough. This also...
Graph homomorphisms and nodal domains [electronic resource]
, Article Linear Algebra and its Applications ; 2006, Volume 418, Issue 1, Pages 44–52 ; Sharif University of Technology
Abstract
In this paper, we derive some necessary spectral conditions for the existence of graph homomorphisms in which we also consider some parameters related to the corresponding eigenspaces such as nodal domains. In this approach, we consider the combinatorial Laplacian and co-Laplacian as well as the adjacency matrix. Also, we present some applications in graph decompositions where we prove a general version of Fisher’s inequality for G-designs
Insight into the corrosion inhibition of Biebersteinia multifida root extract for carbon steel in acidic medium
, Article Science of the Total Environment ; Volume 836 , 2022 ; 00489697 (ISSN) ; Soltani, N ; Tavakkoli, N ; Nejatian, A ; Ebrahimian, J ; Mahdi, M. A ; Salavati Niasari, M ; Sharif University of Technology
Elsevier B.V
2022
Abstract
In this project, the protective effect of Biebersteinia multifida root extract (BMRE) against corrosion of 1018 low carbon steel (1018LCS) in HCl solutions was appraised by assessing weight loss, electrochemical impedance spectroscopy (EIS), and polarization at 25 °C. The maximum inhibitory efficacy for the concentration of 1 g/l of the BMRE was 92.8% at 25 °C after 2 h and increased to 95.3% after 24 h of immersion. Polarization experiments have shown that the extract in acidic solutions can act as a mixed corrosion inhibitor. The corrosion inhibitory efficacy of BMRE decreased with increasing temperature, and at all temperature settings studied, the adsorption of BMRE molecules on 1018 LCS...