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Studying Impediments Social Learning in Economic Policymaking Community of Iran
, M.Sc. Thesis Sharif University of Technology ; Mashayekhi, Ali Naghi (Supervisor)
Abstract
Social learning approach in economic policymaking is introduced against conflict-based approach in the similar context. Helco, 1973 first studied the effects of such a learning in economic policymaking and said ”men collectively wondering what to do… Governments not only ‘power’… they also puzzle.” The important point in studying policymaking through social learning approach is paradigm shifts in peoples’ mental models. In this approach, policies are not only the result of conflict between different interests but also are the output of a learning process. In this research we first assume that social learning has not occurred in policymaking community and that individual learning has...
Designing Torque Contribution Decision- Making unit for Hybrid Vehicles using Fuzzy Logic
, M.Sc. Thesis Sharif University of Technology ; Bagheri shouraki, Saeed (Supervisor) ; Khayyat, Ali Akbar (Supervisor)
Abstract
Energy management in vehicles is ann important issue, because it can significantly influence the performance of the vehicles and component sizing., Although the bbatteries have been widely used in electric vehicles (EVs), However the large current impact of battery cycle life is still a difficult problem that remains to be resolved and because of that, Hybrid Electric Vehicles (HEVs) areis the way that allows to to achievinge the advantages of both engines.Hybrid cars uses both an electric motor and internal combustion engine (ICE) used together, so, itwhich can benefit from the advantages of both engine types. ImprovImprovement ofing energy management in (HEVs) can providedeliver important...
Analysis of the bio-environmental advantages using two types of activated carbon at a petro-chemical water treatment plant
, Article 18th International Congress of Chemical and Process Engineering, CHISA 2008, Prague, 24 August 2008 through 28 August 2008 ; 2008 ; Mansouri, M ; Badry, N
2008
Abstract
Activated carbon powder was analyzed at one of the petro-chemical units in Iran, to determine the usefulness of this material in waste water treatment. Two types of commercial activated carbon powder were used giving different results, attributed to different constituents. For every experiment, 4 kg of activated carbon was used in the pilot plant column. Analysis results on the effect of parameters, e.g., inlet volumetric flow rate of waste water and activated carbon structure, on the plant performance were presented. This is an abstract of a paper presented at the 18th International Congress of Chemical and Process Engineering (Prague, Czech Republic 8/24-28/2008)
Study of ZnO Nanoparticles for the Photocatalytic Degradation of a Organic Pollutant
, M.Sc. Thesis Sharif University of Technology ; Baghalha, Morteza (Supervisor) ; Ahmadpour, Ali ($item.subfieldsMap.e) ; Khorashe, Farhad ($item.subfieldsMap.e)
Abstract
due to high mineralization rate of Zinc oxide، chemical and physical stability, non-toxicity and low price as the most promising photocatalysts studied, although its use is not too satisfactory. Because of the wide energy gap(3.2 ev) and for photocatalytic activity needs to UV light Unfortunately, the solar spectrum is made up only 5-7% of UV light, while 46-47% is the spectrum of visible light and infrared. Doped zinc oxide nanoparticles with metal and non-metallic atoms could increase the photocatalytic properties under visible light irradiation. In this research, nanoparticles of zinc oxide was doped by fluorine as Dopant. The results showed that photocatalytic activity of the modified...
An Investigation on The Effect of Intermediate Deformation Between The Retrogression and Re Aging Process of 7xxx Series of Aluminum Alloys on The Mechanical Properties and Formability of These Alloys
, M.Sc. Thesis Sharif University of Technology ; Karimi Taheri, Ali (Supervisor) ; Kazeminejad, Mohsen (Supervisor)
Abstract
In this research it has been attempted to suggest a modified retrogression and re- aging heat treatment on the sheet of AA7075 alloy with a thickness of 2 mm. The main aim of the research is to reduce the required duration of RRA process while maintaining the value of the conventional tensile strength achieving by the RRA process. This was performed by adding an intermediate warm rolling deformation during the RRA process. The rolling temperature was 180 °C and the rolling reductions were 30%, 40%, 50%. Moreover, the temperature of 170°C was selected as the re-aging temperature, for which the aging time of 0.5, 1, 1.5, 2, and 2.5 hours were examined. This temperature and times were chosen to...
Using goal programming for transportation planning decisions problem in imprecise environment
, Article Australian Journal of Basic and Applied Sciences ; Volume 6, Issue 2 , 2012 , Pages 57-65 ; 19918178 (ISSN) ; Chitgar, S ; Sharif University of Technology
2012
Abstract
In this paper, we present a fuzzy goal programming model for Transportation Planning Decisions (TPD) problem. In real-world applications of the transportation planning decisions problems with multi-objective, input data or related parameters are majority vague/fuzzy. It is hard for decision maker(s) to determine the goal value of each objective precisely as the goal values are imprecise. We consider three methods in the research for solving TPD problem under fuzziness, first method is interactive fuzzy goal programming (IFGP), that this approach aim minimizing the worst upper bound to determine an reasonable solution which is end to the best lower bound of each objective function. Second...
Function Simulation and Performance Evaluation of an Underground Multi-Storey Car Park Ventilation Systems under Normal Condition
, M.Sc. Thesis Sharif University of Technology ; Farhanieh, Bijan (Supervisor)
Abstract
Because of increase in use of cars in recent years, demands for parking spaces have also dramatically grown. To resolve this issue construction of multi-storey underground car parks has sharply increased. Due to the high level of contaminants emitted by cars in parking lots and also the continuous presence of humen within them, the control of pollution level and parking indoor air quality is a vital matter. Type of ventilation systems including modern and conventional used for ventilating parking lots and also exhaust and supply vents locations are the most important factors affecting contaminants distribution. Thus investigation the performance of the conventional and modern ventilation...
Performance Evaluation of H-ZSM-5 Catalyst Improved With Boron in Methanol to Propylene Process
, M.Sc. Thesis Sharif University of Technology ; Khorasheh, Farhad (Supervisor)
Abstract
Propylene is one of the key material in petrochemical industries. In recent years, as propylene demand increases, development of new methods alongside traditional ways in production of propylene seems essential. The production of propylene from methanol using zeolitic catalysts is as one of this new methods. This method in recent years has got attention. H-ZSM-5 zeolite is one of the best catalysts appropriate for this process. However, rapid deactivation is the main problem this catalyst at the present time. Therefore, more research in order to increase stability and lifetime has been performed. The uses of promoters are as one of the simplest improvement methods of H-ZSM-5 zeolite....
An Efficient Reconfigurable Architecture Based on Most Frequent Logic Functions
, M.Sc. Thesis Sharif University of Technology ; Asadi, Hossein (Supervisor)
Abstract
Reconfigurable devices are a popular platform invarious computational fields due to having high performance and flexibility and low non-recurring engineering cost. Generous flexibility of Look-up Tables (LUTs) in implementing arbitrary functions comes withsignificant area and performance overheads as compared with their Application Specific Integrated Circuit (ASIC) equivalent. One approach to alleviate such overheads is to use less flexible logic elements capable to implement majority of logic functions. In this thesis, we first investigate the most frequently used functions in standard benchmarks and then design a set of less-flexible but area-efficient logic cells, called Hard Logics...
An efficient reconfigurable architecture by characterizing most frequent logic functions
, Article 25th International Conference on Field Programmable Logic and Applications, FPL 2015, 2 September 2015 through 4 September 2015 ; Sept , 2015 , Page(s): 1 - 6 ; 9780993428005 (ISBN) ; Khaleghi, B ; Asadi, H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
Generous flexibility of Look-Up Tables (LUTs) in implementing arbitrary functions comes with significant performance and area overheads compared with their Application-Specific Integrated Circuit (ASIC) equivalent. One approach to alleviate such overheads is to use less flexible logic elements capable to implement majority of logic functions. In this paper, we first investigate the most frequently used functions in standard benchmarks and then design a set of less-flexible but area-efficient logic cells, called Hard Logics (HL). Since higher input functions have diverse classes, we leverage Shannon decomposition to break them into smaller ones to either reduce the HL design space complexity...
Effects of different operating parameters on the particle size of silver chloride nanoparticles prepared in a spinning disk reactor
, Article Applied Physics A: Materials Science and Processing ; Volume 120, Issue 1 , July , 2015 , Pages 105-113 ; 09478396 (ISSN) ; Davarpanah, M ; Ahmadpour, A ; Sharif University of Technology
Springer Verlag
2015
Abstract
The aim of this research was to present an experimental method for large-scale production of silver chloride nanoparticles using spinning disk reactor. Silver nitrate and sodium chloride were used as the reactants, and the protecting agent was gelatin. The experiments were carried out in a continuous mode by injecting the reactants onto the surface of the spinning disk, where a chemical precipitation reaction took place to form AgCl particles. The effects of various operating variables, including supersaturation, disk rotational speed, reactants flow rate, disk diameter, and excess ions, on the particle size of products were investigated. In addition, the AgCl nanoparticles were...
Pereparation, Characterization and Photocatalytic Application of Some Polyoxometalates in Degradation of Oraganic Pollutants
, M.Sc. Thesis Sharif University of Technology ; Rahman Setayesh, Shahrbanoo (Supervisor)
Abstract
In this project photocatalysts TiO2, H3PW12O40, H3PMo6W6O40, H3PW12O40 / TiO2, H3PMo6W6O40 / TiO2, K2.5H0.5PW12O40, Cs2.5H0.5PW12O40, (NH4) 2.5H0.5PW12O40 and H3PW12O40 / M-TiO2 that M = La , Ce, Cr, Fe, Co were characterized by techniques DRS, FT-IR, BET, 31P NMR, SEM and XRD. The results of SEM and XRD particle size and page crystalline nanoscale catalysts, with size less than 40nm, respectively. FT-IR analysis confirmed the structure of heteropolyacid was produced. DRS analysis of the degradation reactions during wavelenght longer upheld. Degradation of methylene blue and pollutants such as Tinopal CBS-x to the polyoxometalates keggin is homogeneous and composite titanium dioxide two...
Investigation of Nonlinear Kirchhoff Type Equations
, M.Sc. Thesis Sharif University of Technology ; Hesaaraki, Mahmoud (Supervisor)
Abstract
In this thesis, two kind of Kirchhoff type equations are investigated. for each of them we prove existence and uniqueness of weak solution by letting hypothesizes on problems functions and initial conditions and using Faedo-Galerkin method and some theorems in functional analysis. It is should be mentioned that one of the problems has unique strong solution according to compactness theorems. In the nest step stability of these equations are investigated. for this purpose it is showed that total energy of systems will tend to zero as time goes to infinity. Furthermore at the end of each chapter numerical results are presented to illustrate accuracy of obtained theoretical results. Finally we...
Methanol-to-hydrocarbons product distribution over sapo-34 and zsm-5 catalysts: The applicability of thermodynamic equilibrium and anderson-schulz-flory distribution
, Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 38, Issue 2 , 2019 , Pages 49-59 ; 10219986 (ISSN) ; Yaripour, F ; Ahmadpour, S ; Khorasheh, F ; Sharif University of Technology
Iranian Institute of Research and Development in Chemical Industries
2019
Abstract
The product distribution of methanol to hydrocarbons conversion over SAPO-34 and ZSM-5 catalysts was studied using thermodynamic equilibrium and Anderson-Schulz-Flory (ASF) distributions. The equilibrium compositions were calculated using constrained Gibbs free energy minimization. The effect of catalyst type was considered by setting upper limits to product carbon number due to shape selectivity according to zeotype catalyst channel size; that is, n5 for SAPO-34 but n6 for aliphatic and n10 for aromatic compounds over H-ZSM-5 catalyst. The equilibrium selectivity of kinds of paraffin is negligible over SAPO-34 system while that of olefins is very small over H-ZSM-5, both in agreement...
A computational plastic-damage method for modeling the FRP strengthening of concrete arches
, Article Scientia Iranica ; Volume 26, Issue 4A , 2019 , Pages 2123-2132 ; 10263098 (ISSN) ; Tehrani, Y. N ; Klioei, A. R ; Sharif University of Technology
Sharif University of Technology
2019
Abstract
In this paper, a computational technique is presented based on a concrete plastic-damage model to investigate the effect of FRP strengthening of reinforced concrete arches. A plastic-damage model was utilized to capture the behavior of concrete. The interface between the FRP and concrete was modeled using a cohesive fracture model. In order to validate the accuracy of the damage-plastic model, a single element was employed under monotonic tension, monotonic compression, and cyclic tension loads. An excellent agreement was observed between the predefined strain-stress curve and that obtained by the numerical model. Furthermore, the accuracy of the cohesive fracture model was investigated by...
A computational plastic-damage method for modeling the FRP strengthening of concrete arches
, Article Scientia Iranica ; Volume 26, Issue 4A , 2019 , Pages 2123-2132 ; 10263098 (ISSN) ; Ttehrani, Y. N ; Klioei, A. R ; Sharif University of Technology
Sharif University of Technology
2019
Abstract
In this paper, a computational technique is presented based on a concrete plastic-damage model to investigate the effect of FRP strengthening of reinforced concrete arches. A plastic-damage model was utilized to capture the behavior of concrete. The interface between the FRP and concrete was modeled using a cohesive fracture model. In order to validate the accuracy of the damage-plastic model, a single element was employed under monotonic tension, monotonic compression, and cyclic tension loads. An excellent agreement was observed between the predefined strain-stress curve and that obtained by the numerical model. Furthermore, the accuracy of the cohesive fracture model was investigated by...
Higher-order energy balance method for a series of nonlinear oscillatory systems
, Article Asian-European Journal of Mathematics ; Volume 6, Issue 4 , December , 2013 ; 17935571 (ISSN) ; Safaie, N ; Ahmadpour, M. A ; Askari, H ; Sharif University of Technology
2013
Abstract
The aim of this paper is to use higher-order energy balance method as a novel solution procedure for investigation the nonlinear oscillation of various systems. The method is associated with collocation method and employed for a group of nonlinear problems including pure cubic nonlinearity, fractional elastic force and duffing harmonic terms. Obtained results are evaluated by comparing with the classical balance method and also the exact solutions computed numerically. It is shown our solution procedure achieves more accurate results versus the classical solution and higher agreement are observed between the newer solutions and the exact ones for the systems. Effect of initial conditions in...
Rapid removal of heavy metal ions from aqueous solutions by low cost adsorbents
, Article International Journal of Global Environmental Issues ; Volume 12, Issue 2-4 , 2012 , Pages 318-331 ; 14666650 (ISSN) ; Rohani Bastami, T ; Tahmasbi, M ; Zabihi, M ; Sharif University of Technology
Interscience
2012
Abstract
In the present investigation, different agricultural solid wastes namely: eggplant hull (EH), almond green hull (AGH), and walnut shell (WS), that are introduced as low cost adsorbents, were used for the removal of heavy metals (cobalt, strontium and mercury ions) from aqueous solutions. Activation process and/or chemical treatments using H 2O 2 and NH 3 were performed on these raw materials to increase their adsorption performances. The effectiveness of these adsorbents was studied in batch adsorption mode under a variety of experimental conditions such as: different chemical treatments, various amounts of adsorbents, initial metal-ion concentrations, pH of solutions, contact times, and...
Model for excess mass-transfer resistance of contaminated liquid-liquid systems
, Article Industrial and Engineering Chemistry Research ; Volume 46, Issue 5 , 2007 , Pages 1563-1571 ; 08885885 (ISSN) ; Ghasemian, S ; Bastani, D ; Ahmadpour, N ; Sharif University of Technology
2007
Abstract
The prediction of mass-transfer rates into and from moving drops in the liquid-liquid systems has usually used the well-known Whitman two-film theory approach. According to the latter, the total resistance to mass transfer resides on each side of the interface and is described by the individual film mass-transfer coefficients for the continuous and dispersed phases in the absence of surface-active agents (contaminants). In the present work, the same approach has been used to model the excess mass-transfer resistance exerted by surface-active agents in the continuous phase. To achieve this goal, an experimental investigation has been conducted on the mass transfer into and from single drops...
Improvement of Industrial Symbiosis Between Greenhouses and Industrial Waste Heat Sources by Employing Organic Rankine Cycle (ORC)
, M.Sc. Thesis Sharif University of Technology ; Roshandel, Ramin (Supervisor) ; Shafii, Mohammad Behshad (Co-Supervisor)
Abstract
The water crisis caused by climate change and anthropogenic activities in Iran has affected the daily lives of the people, and since the agricultural sector has a large share of water consumption, greenhouse cultivation and indoor farming has been developing in this country, to improve water productivity. Considering that the main source of energy supply in greenhouses is fossil fuels, in this work, the possibility of improving Industrial Symbiosis (IS) between greenhouses and waste heat sources in industries by employing the Organic Rankin Cycle (ORC) has been studied, in order to meet the heating demand of greenhouses in a more sustainable and eco-friendly way.Based on that, by modeling...