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rahmani--fatemeh
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ChemInform abstract: microwave-assisted rapid ketalization/acetalization of aromatic aldehydes and ketones in aqueous media [electronic resource]
, Article Journal of Chemical Research ; September 1999, Volume -, Number 9; Page(s) 562 to 563 ; Mirjalili, Bibi Fatemeh ; Sharif University of Technology
Abstract
Aromatic aldehydes and ketones are readily acetalized or ketalized under microwave irradiation in the presence of water as a solvent
Synthesis and characterization of poly(methacrylates) containing spiroacetal and norbornene moieties in side chain [electronic resource]
, Article Journal of Applied Polymer Science ; Volume 77, Issue 1, pages 30–38, 5 July 2000 ; Mirjalili, Bibi Fatemeh ; Sharif University of Technology
Abstract
A four-step synthetic strategy was applied to achieve novel methacrylic monomers. 5-Norbornene-2,2-dimethanol was prepared from a Diels–Alder reaction of cyclopentadiene and acrolein, followed by the treatment of the adduct with an HCHO/KOH/MeOH solution. The resulting 1,3-diol (1) was then acetalized with different aromatic aldehydes having OH groups on the ring to produce four spiroacetal derivatives. The reaction of methacryloyl chloride with the phenolic derivatives led to four new methacrylic monomers that were identified spectrochemically (mass, FTIR, 1H-NMR, and 13C-NMR spectroscopy). Free radical solution polymerization was used to prepare novel spiroacetal–norbornene containing...
Prediction of DNA/RNA Sequence Binding Site to Protein with the Ability to Implement on GPU
, M.Sc. Thesis Sharif University of Technology ; Koohi, Sommaye (Supervisor)
Abstract
Based on the importance of DNA/RNA binding proteins in different cellular processes, finding binding sites of them play crucial role in many applications, like designing drug/vaccine, designing protein, and cancer control. Many studies target this issue and try to improve the prediction accuracy with three strategies: complex neural-network structures, various types of inputs, and ML methods to extract input features. But due to the growing volume of sequences, these methods face serious processing challenges. So, this paper presents KDeep, based on CNN-LSTM and the primary form of DNA/RNA sequences as input. As the key feature improving the prediction accuracy, we propose a new encoding...
Cross-Lingual Speaker Adaptation for Statistical Parametric Speech Synthesis
, M.Sc. Thesis Sharif University of Technology ; Sameti, Hossein (Supervisor)
Abstract
Speech synthesis and its applications have been very attractive recently. The main purpose of this technique is to produce a speech signal with natural characteristics of human speech like prosody and emotion. Among all existing methods for speech synthesis, statistical parametric speech synthesis methods are more promising because ofhigher flexibility in comparison to other methods. One of the applications of speech synthesis is speech to speech translation. In these systems, the generated voice in target language should have the same characteristics as the input voice in source language. The main purpose of this research is to review and evaluate the cross lingual speaker adaptation...
Hydroelastic Analysis of Surface Piercing Propeller
, M.Sc. Thesis Sharif University of Technology ; Seif, Mohamad Saeed (Supervisor)
Abstract
Surface piercing propellers are particular type of supercavitating propellers that are commonly used for High-speed vessels. Most studies on this type of propellers has been investigating the hydrodynamic forces. But in recent years with increase in SPPs diameter used in vessels, structural analysis of this type of propellers is considered. For this purpose, studies on the stresses exerted on the propeller structures under load is done with the help of Hydro elastic methods. In this type of analysis, structura of propeller is intended to be flexible and Displacements under pressure checked and Tensions resulting from it are studied.
The present Thesis using ANSYS software to analyze a...
The present Thesis using ANSYS software to analyze a...
Data-Driven Pricing Based on Demand Prediction Using Machine Learning Methods
, M.Sc. Thesis Sharif University of Technology ; Sedghi, Nafiseh (Supervisor)
Abstract
Pricing plays an important and essential role in the profit and income of companies. The importance of pricing is not only related to its role in the company's profitability, but it also changes the customer's understanding and loyalty towards the company and can create the company's reputation or destroy it. Determining the right price will increase product sales and increase customer loyalty and create a competitive advantage for the company. One of the most important and influential variables in product pricing is the amount of demand. The main challenge of companies for product pricing is the uncertainty in their demand. In order to deal with this problem, data-driven pricing is used....
Design of Low-Power Zero Temperature Coefficient (ZTC) CMOS Oscillators
, M.Sc. Thesis Sharif University of Technology ; Akbar, Fatemeh (Supervisor)
Abstract
The increasing demand for autonomous vehicles and reliable communication protocols and hardware interfaces, such as CAN bus and USB, underscores the necessity for stable clock sources that maintain a low temperature coefficient (TC) over wide temperature ranges. This demand is particularly emphasized in applications such as wearables, network sensors, downhole devices, WSNs, and IoT, where long-lasting battery life and frequency-stable clock sources over a broad temperature range (e.g. -20 °C to 100 °C) are crucial. Traditionally, variations in frequency caused by temperature have been mitigated by employing off-chip components like crystals or ceramic based oscillators, but this approach...
Design of Low Power Harmonic Rejection Mixer for Wideband Application
, M.Sc. Thesis Sharif University of Technology ; Akbar, Fatemeh (Supervisor)
Abstract
The increasing demand for communication bandwidth and limited spectrum availability have heightened the complexity of radio front-end circuits in IoT applications. Achieving spectral efficiency is a key challenge, particularly for IoT devices operating at specific frequency bands such as 315 MHz, 433 MHz, 868 MHz, and 915 MHz.Due to the limited linearity of the transmit path, harmonic distortion components, known as counter intermodulation (CIM) products, are generated. These CIM products can directly fall into the receiver (RX) band or enter it via cross-modulation, thereby degrading the frequency division performance. Additionally, CIM products can interfere with protected bands, violating...
Silica chloride/wet SiO2 as a novel heterogeneous system for the deprotection of acetals under mild conditions [electronic resource]
, Article Phosphorus, Sulfur, and Silicon and the Related Elements ; Volume 178:2667-2670, Issue 12, 2003 ; Pourjavadi, Ali ; Zolfigol, Mohammad Ali ; Bamoniri, Abdolhamid
Abstract
A combination of silica chloride and wet SiO2 was used as an effective deacetalizating agent for the conversion of acetals to their corresponding carbonyl derivatives under mild and heterogeneous condition
AI planning search time and space reduction technique for the problem of web service composition
, Article 2008 AAAI Workshop, Chicago, IL, 13 July 2008 through 14 July 2008 ; Volume WS-08-10 , 2008 , Pages 173-174 ; Sharif University of Technology
2008
Abstract
One of challenging problems in the domain of web services is the web service composition (i.e the task of composing web services to create new services, capable of fulfilling a need that no single service can satisfy). In real application, there will be a lot of relevant web services for a simple goal, so the search space for such a problem is huge. In this research statement, we show how by extracting some prior knowledge and using simple heuristics, search space and search time can be reduced significantly
The Impact of AV and CAV Vehicles on Capacity and Traffic Flow with Cooperative Lane changing in Mixed Traffic Environment
, M.Sc. Thesis Sharif University of Technology ; Nassiri, Habibollah (Supervisor)
Abstract
Autonomous vehicles, as an integral part of intelligent transportation systems, will play a significant role in the future of transportation services. These vehicles have a high potential to improve road traffic capacity and the efficiency of transportation systems. One type of autonomous vehicle is the connected and autonomous vehicle (CAV), which can communicate with each other, roadside units, traffic control signals, and other infrastructures or devices. This study investigates the impact of autonomous vehicles and connected and autonomous vehicles on the traffic flow of the Tehran-Karaj freeway and vice versa, under various penetration rates and in a mixed traffic environment. In this...
The Impact of Integrated Prediction and Optimization on the the Bullwhip Effect in supply chains
, M.Sc. Thesis Sharif University of Technology ; Sedghi, Nafiseh (Supervisor)
Abstract
The Bullwhip effect is a phenomenon that refers to the amplification of demand variance as one moves upstream in a supply chain. This effect imposes additional costs on the supply chain and complicates inventory planning. Several factors contribute to the emergence of this phenomenon, one of which is demand forecasting. Since the demand faced by each level of the supply chain is uncertain, every level must first forecast demand in order to plan its inventory and meet customer requirements. However, this very process of forecasting contributes to the bullwhip effect. In this study, we investigate the impact of machine learning and deep learning forecasting methods, along with their...
A Comprehensive Review of Studies Conducted in Entrepreneurship Education in Order to Achieve a Codified Framework
, M.Sc. Thesis Sharif University of Technology ; Feyzbakhsh, Alireza (Supervisor)
Abstract
In the current situation and considering the economic conditions, entrepreneurship and self-employment are important factors of business growth. To prepare people in this field, there is a need for effective training that can motivate people. Identifying the effective methods and different dimensions of the entrepreneurship education framework that can lead to setting up a successful program for training people and facilitate the way to achieve the goal of education is one of the important goals of this research. By studying the literature from 2010 onwards, this research systematically examined 96 articles and tried to improve the framework of entrepreneurship education that was stated in...
Design and optimization of the spallation neutron source target system using 800 MeV protons produced in the synchrotron using Geant4 Monte Carlo code
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Abolfazl (Supervisor)
Abstract
Among various neutron sources such as fission reactors, radioisotopic sources, photoneutron reactions, and others, the spallation neutron source has attracted significant attention due to advantages like high flux, notable neutron yield, and a broad energy spectrum. The spallation process occurs when high-energy light particles, typically protons in the order of giga-electron volts, collide with heavy targets such as lead or mercury. This interaction produces a large number of neutrons, protons, deuterons, pions, and other particles. To increase neutron production efficiency and achieve a desirable energy spectrum, a target system composed of a target, moderator, and reflector is used. In...
Robust optimal control for large-scale systems with state delay
, Article Transactions of the Institute of Measurement and Control ; Vol. 36, Issue. 4 , June , 2014 , pp. 551-558 ; ISSN: 01423312 ; Sadati, N ; Sharif University of Technology
2014
Abstract
Optimal control of large-scale uncertain dynamic systems with time delays in states is considered in this paper. For this purpose, a two-level strategy is proposed to decompose the large-scale system into several interconnected subsystems at the first level. Then optimal control inputs are obtained by minimization of convex performance indices in presence of uncertainties, in the form of states and interactions feedback. The solution is achieved by bounded data uncertainty problems, where the uncertainties are only needed to be bounded and it is not required to satisfy the so-called 'matching conditions'. At the second level, a simple substitution-type interaction prediction method is used...
Dynamic behavior of pile foundations under cyclic loading in liquefiable soils
, Article Computers and Geotechnics ; Volume 40 , 2012 , Pages 114-126 ; 0266352X (ISSN) ; Pak, A ; Sharif University of Technology
2012
Abstract
In this paper, a fully coupled three-dimensional dynamic analysis is carried out to investigate the dynamic behavior of pile foundations in liquefied ground. A critical state bounding surface plasticity model is used to model soil skeleton, while a fully coupled (u- P) formulation is employed to analyze soil displacements and pore water pressures. Furthermore, in this study, variation of permeability coefficient during liquefaction is taken into account; the permeability coefficient is related to excess pore water pressure ratio. Results of a centrifuge test on pile foundations are used to demonstrate the capability of the model for reliable analysis of piles under dynamic loading. Then, the...
Two-level optimal load-frequency control for multi-area power systems
, Article International Journal of Electrical Power and Energy Systems ; Volume 53, Issue 1 , December , 2013 , Pages 540-547 ; 01420615 (ISSN) ; Sadati, N ; Sharif University of Technology
2013
Abstract
In large-scale power systems, classical centralized control approaches may fail due to geographically distribution of information and decentralized controllers result in sub-optimal solution for load-frequency control (LFC) problems. In this paper, a two-level structure is presented to obtain optimal solution for LFC problems and also reduce the computational complexity of centralized controllers. In this approach, an interconnected multi-area power system is decomposed into several sub-systems (areas) at the first-level. Then an optimization problem in each area is solved separately, with respect to its local information and interaction signals coming from other areas. At the second-level,...
Hierarchical optimal robust load-frequency control for power systems
, Article IET Generation, Transmission and Distribution ; Volume 6, Issue 4 , 2012 , Pages 303-312 ; 17518687 (ISSN) ; Sadati, N ; Sharif University of Technology
2012
Abstract
In this study, a hierarchical optimal robust controller is presented for the power system load-frequency control problem. In this approach, the multi-area power system is first decomposed into several sub-systems (areas). Then by using a two-level control strategy, the overall optimal solution is obtained. At the first level, the optimal control of each area is obtained with respect to local information and also considering interactions coming from other areas. At the second level, by using a coordination strategy, the local controllers will converge to global solution and optimal robust controller is achieved. This approach is applicable to both single-area and multi-area interconnected...
Mechanical properties of uncoated and aluminide-coated rené 80
, Article Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science ; Volume 41, Issue 1 , 2010 , Pages 125-137 ; 10735623 (ISSN) ; Nategh, S ; Sharif University of Technology
2010
Abstract
Nickel-base superalloys such as René 80 are widely used in manufacturing aircraft turbine blades. They are usually coated in order to increase their wear, oxidation, erosion, and hot corrosion properties against environmental degradation. In this article, the mechanical behavior (tensile and low-cycle fatigue (LCF)) of uncoated and aluminide-coated (CODEP-B) René 80 has been studied at 871 °C and 982 °C. Experimental results show that the tensile properties of coated specimens are relatively lower than those of uncoated ones in the same conditions, but application of coating increases the LCF life of René 80 at T = 871 °C, 982 °C, R = (εmin/εmax) = 0, strain rate of 2 × 10-3 s-1, and Δεt =...
Dynamic economic evaluation of distribution automation systems
, Article 2009 International Conference on Electric Power and Energy Conversion Systems, EPECS 2009 ; 2009 ; 9789948427155 (ISBN) ; Ehsan, M ; Sharif University of Technology
2009
Abstract
In a deregulated environment of power distribution industry, a comprehensive economic evaluation for the implementation of distribution automation (DA) systems is inevitable. Using the presented methodology in this paper and system dynamics approach, it is efficiently possible to deal with variation of the economic parameters such as the interest rate, inflation rate, energy supply cost, load growth, etc. In this paper, economic short-run and long-run impacts of DA systems are evaluated from utility point of view. Also economic benefits from customers' point of view are analyzed. A practical pricing strategy for maximizing the utility profit is suggested depending on the underlying market...