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    The ∑ 1-Provability Logic of Intuitionistic Arithmetic

    , Ph.D. Dissertation Sharif University of Technology Mojtahedi, Mojtaba (Author) ; Ardeshir, Mohammad (Supervisor)
    Abstract
    In this dissertation, we study (first-order) arithmetical interpretations for propositional (modal and non-modal) logics. More precisely, the following results are included in this dissertation: an axiomatization for provability logic of Heyting Arithmetic, HA, and its self-completion HA := HA + PrHA(⌜A⌝) ! A for 1-substitutions is provided, and their arithmetical completeness theorems are proved. We also show that they are decidable. The de Jongh property for Basic Arithmetic BA, HA and HA + □ are proved  

    Optimization of Pressure Leaching of Chalcopyrite Concentrate with Oxygen and Kinetics Study of the Process in Sulfuric Acid Solution

    , M.Sc. Thesis Sharif University of Technology Mojtahedi, Behrad (Author) ; Yoozbashizadeh, Hossein (Supervisor)
    Abstract
    The enormous benefits of hydrometallurgical processes have led to the progressive metals extraction industry. Many studies are carried out on the application of these processes in the copper extraction industry. In this research, the oxygen pressure leaching of chalcopyrite concentrate was studied. Experiments were carried out under conditions of the solid-liquid ratio of 0.1, agitation speed of 750 rpm, and sulfuric acid concentration of 2M in a stainless-steel autoclave system. Central composite design (CCD) was used to design experiments, and three factors of temperature, time, and pressure of oxygen, were selected as design variables. The obtained model for %Cu includes parameters of... 

    Assessment of Water and Sewage Facilities of Kish Island and Offering Solutions in Emergency Conditions (A Case Study on Kish Island)

    , M.Sc. Thesis Sharif University of Technology Mojtahedi, Amir (Author) ; Hashemian, Jamal (Supervisor)
    Abstract
    Vulnerability of water and sewage infrastructure in Kish Island survey versus natural and unnatural threats. It is important to know what to do when crisis or unpredicted event occurs in the Island. Decision makers and master managers of the Island, as the main custodians make suitable and effective reactions and decisions so that the impact of threats is reduced to minimum. According to the threats, there are short term and long term solutions. These solutions can be applied when the Island is encountered with crisis  

    A novel probabilistic simulation approach for forecasting the safety factor of slopes: a case study

    , Article Engineering with Computers ; 2018 , Pages 1-10 ; 01770667 (ISSN) Mojtahedi,S. F. F ; Tabatabaee, S ; Ghoroqi, M ; Soltani Tehrani, M ; Gordan, B ; Ghoroqi, M ; Sharif University of Technology
    Springer London  2018
    Abstract
    Stabilization of slopes is considered as the aim of the several geotechnical applications such as embankment, tunnel, highway, building and railway and dam. Therefore, evaluation and precise prediction of the factor of safety (FoS) of slopes can be useful in designing these important structures. This research is carried out to evaluate the ability of Monte Carlo (MC) technique for the forecasting the FoS of many homogenous slopes in the static condition. Moreover, the sensitivity of the FoS on the effective parameters was identified. To do this, the most important factors on FoS, such as angle of internal friction (Formula presented.), slope angle (Formula presented.) and cohesion (Formula... 

    A novel probabilistic simulation approach for forecasting the safety factor of slopes: a case study

    , Article Engineering with Computers ; Volume 35, Issue 2 , 2019 , Pages 637-646 ; 01770667 (ISSN) Mojtahedi, S. F. F ; Tabatabaee, S ; Ghoroqi, M ; Soltani Tehrani, M ; Gordan, B ; Ghoroqi, M ; Sharif University of Technology
    Springer London  2019
    Abstract
    Stabilization of slopes is considered as the aim of the several geotechnical applications such as embankment, tunnel, highway, building and railway and dam. Therefore, evaluation and precise prediction of the factor of safety (FoS) of slopes can be useful in designing these important structures. This research is carried out to evaluate the ability of Monte Carlo (MC) technique for the forecasting the FoS of many homogenous slopes in the static condition. Moreover, the sensitivity of the FoS on the effective parameters was identified. To do this, the most important factors on FoS, such as angle of internal friction (∅) , slope angle (α) and cohesion (C) were investigated and used as the... 

    Assessing the vulnerability of Iran to subsidence hazard using a hierarchical FUCOM-GIS framework

    , Article Remote Sensing Applications: Society and Environment ; Volume 31 , 2023 ; 23529385 (ISSN) Sadeghi, H ; Golaghaei Darzi, A ; Voosoghi, B ; Akbari Garakani, A ; Ghorbani, Z ; Fazel Mojtahedi, F ; Sharif University of Technology
    Elsevier B.V  2023
    Abstract
    In engineering practice, land subsidence is considered a threat to the infrastructure and lifelines massively distributed globally. In this study, a combined methodology of full consistency decision-making (FUCOM) and the geographical information system (GIS) was employed to assess the vulnerability of Iran to subsidence. Accordingly, a new hierarchical FUCOM-GIS framework was developed. The FUCOM was first used to evaluate the weight of various causative factors. Afterward, the GIS was employed to superimpose several layers to produce a land subsidence susceptibility map (LSSM) of Iran. The results revealed water stress, groundwater depletion, soil type, geological time scale, and rainfall... 

    Pressure leaching of chalcopyrite concentrate with oxygen and kinetic study on the process in sulfuric acid solution

    , Article Transactions of the Indian Institute of Metals ; Volume 73, Issue 4 , 6 March , 2020 , Pages 975-987 Mojtahedi, B ; Rasouli, S ; Yoozbashizadeh, H ; Sharif University of Technology
    Springer  2020
    Abstract
    In this research work, the pressure leaching of chalcopyrite concentrate with oxygen was studied. Experiments were carried out under conditions of the solid–liquid ratio of 0.1, agitation speed of 750 rpm, and sulfuric acid concentration of 2 M in a stainless-steel autoclave system under 0.6 to 1 MPa oxygen gas. Central composite design was used to design experiments, and three factors of temperature, time, and oxygen pressure were selected as the design variables. A linear model for %Cu and a quadratic model for %Fe were proposed by Minitab Software. The results showed that temperature is the most effective factor in chalcopyrite leaching. Under optimal conditions, 93.08% of copper with the... 

    Investigation of Ardabil Plain Subsidence with Respect to Changes in Groundwater Level and Climate Fluctuations

    , M.Sc. Thesis Sharif University of Technology Fazel Mojtahedi, Farid (Author) ; Khosravi, Ali (Supervisor)
    Abstract
    The subsidence phenomenon in the past years has caused many problems and issues for the agricultural lands, roads, power transmission lines, energy etc., due to different reasons including over use of groundwater resources and changes in climate. This phenomenon has been observed in different plains of the country including the Khorasan, Kerman, Hamedan, Ghazvin and Isfahan plains and has caused many damages to infrastructure and agricultural products in the mentioned regions. In this research the main factors which have affected the subsidence phenomenon especially reduced ground water table and climate changes in Ardebil plain, are taken into account and some studies which comprise... 

    An Artificial Intelligence Based Data-Driven Method for Forecasting Unconfined Compressive Strength of Cement Stabilized Soil by Deep Mixing Technique

    , Article Geotechnical and Geological Engineering ; Volume 41, Issue 1 , 2023 , Pages 491-514 ; 09603182 (ISSN) F. Mojtahedi, F ; Ahmadihosseini, A ; Sadeghi, H ; Sharif University of Technology
    Springer Science and Business Media Deutschland GmbH  2023
    Abstract
    The cost constraints imposed on construction projects specially ground improvements by the deep mixing technique (DMT) highlight the role of efficient optimization. In this study, a systematic artificial neural network (ANN)-based method to address this practical issue is presented. To achieve this goal, the mutual information method is firstly used to select the most important input parameters for training. Secondly, different ANN architectures are examined to find the network with the smallest error by training and optimizing several multi-layer perceptron networks using a grid search-based technique. The model is then generalized by employing the K-fold and Hold-out cross-validation... 

    Unification types in Euclidean modal logics

    , Article Logic Journal of the IGPL ; Volume 31, Issue 3 , 2023 , Pages 422-440 ; 13670751 (ISSN) Alizadeh, M ; Ardeshir, M ; Balbiani, P ; Mojtahedi, M ; Sharif University of Technology
    Oxford University Press  2023
    Abstract
    We prove that K5 and some of its extensions that do not contain K4 are of unification type 1. © The Author(s) 2022. Published by Oxford University Press. All rights reserved  

    Efficient and practical solvent-free oxidation of alcohols using microwave irradiation

    , Article Journal of Chemical Research - Part S ; Issue 6 , 2002 , Pages 286-287 ; 03082342 (ISSN) Mojtahedi, M. M ; Sharifi, A ; Kaamyabi, S ; Saidi, M. R ; Sharif University of Technology
    Scientific Reviews Ltd  2002
    Abstract
    Alcohols are oxidised rapidly to the corresponding carbonyl compounds by montmorillonite KSF or silica supported barium manganate, under solvent-free conditions and microwave irradiation  

    Microwave-assisted aminomethylation of electron-rich compounds under solvent-free condition

    , Article Synthetic Communications ; Volume 30, Issue 1 , 2000 , Pages 69-72 ; 00397911 (ISSN) Mojtahedi, M. M ; Sharifi, A ; Mohsenzadeh, F ; Saidi, M. R ; Sharif University of Technology
    Marcel Dekker Inc  2000
    Abstract
    Electron-rich aromatic compounds react with formaldehyde and a secondary amine under solvent-free condition, in the presence of acidic alumina in a commercial microwave oven or at room temperature to produce aminomethylated products in good to excellent yields  

    Numerical finite element analysis of laterally loaded fin pile in sandy soil

    , Article Innovative Infrastructure Solutions ; Volume 4, Issue 1 , 2019 ; 23644176 (ISSN) Yaghobi, M. H ; Hanaei, F ; Fazel Mojtahedi, S. F ; Rezaee, M ; Sharif University of Technology
    Springer  2019
    Abstract
    In the present study, the behavior of fin pile under lateral loading was investigated by ABAQUS software. First, the generated model was verified against an available experimental small-scale test in the literature. Having conducted verification, a study was carried out on the fin pile dimensions under lateral loading. Different parameters, such as pile diameter, fin’s length, and width, were studied. Moreover, a study on the fin’s aspect ratio by setting fin’s area constant was conducted, and then, optimum fin’s ratio was obtained. The results indicated that both fin’s length and width could improve pile efficiency under lateral loading, yet fin’s length had a more critical impact, and... 

    Silylation of hydroxy groups with HMDS under microwave irradiation and solvent-free conditions

    , Article Phosphorus, Sulfur and Silicon and Related Elements ; Volume 177, Issue 2 , 2002 , Pages 289-292 ; 10426507 (ISSN) Mojtahedi, M. M ; Saidi, M. R ; Bolourtchian, M ; Heravi, M. M ; Sharif University of Technology
    2002
    Abstract
    Phenols and alcohols are silylated with hexamethyldisilazane (HMDS) under microwave irradiation in solvent-free condition in good to excellent yields  

    Microwave promoted efficient synthesis of substituted uracils and thiouracils under solvent-free conditions

    , Article Synthetic Communications ; Volume 32, Issue 6 , 2002 , Pages 851-855 ; 00397911 (ISSN) Mojtahedi, M. M ; Saidi, M. R ; Shirzi, J. S ; Bolourtchian, M ; Sharif University of Technology
    2002
    Abstract
    Several substituted uracils and thiouracils were synthesized in good yields by one-pot condensation reaction of methyl or ethyl β-ketoesters and urea (or thiourea) in solvent-free conditions under microwave irradiation and in short time  

    Microwave assisted selective oxidation of benzylic alcohols with calcium hypochlorite under solvent-free conditions

    , Article Monatshefte fur Chemie ; Volume 132, Issue 5 , 2001 , Pages 655-658 ; 00269247 (ISSN) Mojtahedi, M. M ; Saidi, M. R ; Bolourtchian, M ; Shirzi, J. S ; Sharif University of Technology
    2001
    Abstract
    A remarkably fast microwave assisted selective oxidation of benzylic alcohols with calcium hypochlorite under solvent-free conditions is described  

    Ultrasound accelerated reductive coupling of imine or iminium ion generated in 5m lithium perchlorate solution by lithium metal

    , Article Synthetic Communications ; Volume 31, Issue 23 , 2001 , Pages 3587-3592 ; 00397911 (ISSN) Mojtahedi, M. M ; Saidi, M. R ; Shirzi, J. S ; Bolourtchian, M ; Sharif University of Technology
    2001
    Abstract
    A novel one-pot reductive coupling of imine or iminium ion generated in the concentrated ethereal lithium perchlorate solution was achieved in the presence of lithium metal. The yield of the reaction depends on the reactivity preformed imine or iminium ion. Diamines were formed with high diastereoselectivity in some cases in about 5 h. The reaction time was doubled without the use of ultrasound acceleration  

    Solvent-free three-component condensation reaction of aromatic ketones with aliphatic amines and formaldehyde

    , Article Journal of Chemical Research - Part S ; Issue 8 , 2000 , Pages 380-381 ; 03082342 (ISSN) Mojtahedi, M. M ; Saidi, M. R ; Sharifi, A ; Noushabadi, M ; Bolourtchian, M ; Sharif University of Technology
    Scientific Reviews Ltd  2000
    Abstract
    A solvent-free procedure for the synthesis of several 1-aryl-2-(dialkylaminomethyl)-prop-2-en-1-ones 3 (a-e) and 4 (a-e) is reported. Reaction of arylmethyl ketones with formaldehyde and dialkylamines, such as diethyl- or dibutylamines at room temperature in silica gel produce 3 and 4 with moderate yields  

    Proposing a novel hybrid intelligent model for the simulation of particle size distribution resulting from blasting

    , Article Engineering with Computers ; 2018 , Pages 1-10 ; 01770667 (ISSN) Mojtahedi, S. F. F ; Ebtehaj, I ; Hasanipanah, M ; Bonakdari, H ; Bakhshandeh Amnieh, H ; Sharif University of Technology
    Springer London  2018
    Abstract
    In the open-pit mines and civil projects, drilling and blasting is the most common method for rock fragmentation aims. This article proposes a new hybrid forecasting model based on firefly algorithm, as an algorithm optimizer, combined with the adaptive neuro-fuzzy inference system for estimating the fragmentation. In this regard, 72 datasets were collected from Shur river dam region, and the required parameters were measured. Using the different input parameters, six hybrid models were constructed. In these models, 58 and 14 data were used for training and testing, respectively. The proposed hybrid models were then evaluated in accordance with statistical criteria such as coefficient of... 

    Proposing a novel hybrid intelligent model for the simulation of particle size distribution resulting from blasting

    , Article Engineering with Computers ; Volume 35, Issue 1 , 2019 , Pages 47-56 ; 01770667 (ISSN) Mojtahedi, S. F. F ; Ebtehaj, I ; Hasanipanah, M ; Bonakdari, H ; Bakhshandeh Amnieh, H ; Sharif University of Technology
    Springer London  2019
    Abstract
    In the open-pit mines and civil projects, drilling and blasting is the most common method for rock fragmentation aims. This article proposes a new hybrid forecasting model based on firefly algorithm, as an algorithm optimizer, combined with the adaptive neuro-fuzzy inference system for estimating the fragmentation. In this regard, 72 datasets were collected from Shur river dam region, and the required parameters were measured. Using the different input parameters, six hybrid models were constructed. In these models, 58 and 14 data were used for training and testing, respectively. The proposed hybrid models were then evaluated in accordance with statistical criteria such as coefficient of...