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jalali--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...
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...
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....
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...
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
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...
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...
Evaluation of the Damage to Steel MRF Structures Under Near Field Earthquake Pulses Using a Performance-Based Design Approach
, M.Sc. Thesis Sharif University of Technology ; Rahimzadeh Rofooei, Fayaz (Supervisor)
Abstract
Research on the characteristics of the near field earthquakes has been very popular in recent years due to the considerable damages they have caused to the structures located within the vicinity of seismic sources. The incapability of response spectra for structural damage assessment has been revealed through recent investigations. The recorded data show that the near field earthquakes are often accompanied by a large energy pulse in the beginning of the records caused by the so-called directivity phenomenon. That has encouraged many researchers to study the possibility of using the velocity pulse of these records to evaluate the imposed seismic demands on structures. Thus, investigating the...
Oxidative Addition of Amines to Aldehydes Catalyzed by Supported Cobalt Nanoparticles on SBA-15
, M.Sc. Thesis Sharif University of Technology ; Saidi, Mohamad Reza (Supervisor) ; Rajabi, Fatemeh (Co-Advisor)
Abstract
Considering the widespread applications of amides, synthesis of these compounds is of great importance. The one pot oxidative addition of amines to aldehydes is one of the most simple and appealing approaches to synthesis amides. With the aim of developing a mild and convenient approach towards preparation of amides, numerous methods have been reported for this important process over the past few decades. These improvements have been mostly related to the optimization of reaction conditions and the use of more challenging substrates including diverse derivatives of aldehydes, and also design a novel and effective catalytic systems. Due to the various advantages of supported heterogeneous...
Global drag-induced instabilities in protoplanetary disks
, Article Astrophysical Journal ; Volume 772, Issue 1 , 2013 ; 0004637X (ISSN) ; Sharif University of Technology
2013
Abstract
We use the Fokker-Planck equation and model the dispersive dynamics of solid particles in annular protoplanetary disks whose gas component is more massive than the particle phase. We model particle-gas interactions as hard sphere collisions, determine the functional form of diffusion coefficients, and show the existence of two global unstable modes in the particle phase. These modes have spiral patterns with the azimuthal wavenumber m = 1 and rotate slowly. We show that in ring-shaped disks, the phase-space density of solid particles increases linearly in time toward an accumulation point near the location of pressure maximum, while instabilities grow exponentially. Therefore, planetesimals...
Finite element modelling of perturbed stellar systems
, Article Monthly Notices of the Royal Astronomical Society ; Volume 404, Issue 3 , Jan , 2010 , Pages 1519-1528 ; 00358711 (ISSN) ; Sharif University of Technology
2010
Abstract
I formulate a general finite element method (FEM) for self-gravitating stellar systems. I split the configuration space to finite elements, and express the potential and density functions over each element in terms of their nodal values and suitable interpolating functions. General expressions are then introduced for the Hamiltonian and phase-space distribution functions of the stars that visit a given element. Using the weighted residual form of Poisson's equation, I derive the Galerkin projection of the perturbed collisionless Boltzmann equation, and assemble the global evolutionary equations of nodal distribution functions. The FEM is highly adaptable to all kinds of potential and density...
Chemometrical modeling of electrophoretic mobilities in capillary electrophoresis
, Article Chemometric Methods in Capillary Electrophoresis ; 2009 , Pages 323-343 ; 9780470393291 (ISBN) ; Sharif University of Technology
John Wiley & Sons, Inc
2009
Unstable disk galaxies. I. Modal properties
, Article Astrophysical Journal ; Volume 669, Issue 1 , 2007 , Pages 218-231 ; 0004637X (ISSN) ; Sharif University of Technology
Institute of Physics Publishing
2007
Abstract
I utilize the Petrov-Galerkin formulation and develop a new method for solving the unsteady collisionless Boltzmann equation in both the linear and nonlinear regimes. In the first-order approximation, the method reduces to a linear eigen-value problem which is solved using standard numerical methods. I apply the method to the dynamics of a model stellar disk which is embedded in the field of a soft-centered logarithmic potential. The outcome is the full spectrum of eigen-frequencies and their conjugate normal modes for prescribed azimuthal wavenumbers. The results show that the fundamental bar mode is isolated in the frequency space, while spiral modes belong to discrete families that...
Neural networks in analytical chemistry
, Article Methods in Molecular Biology ; Volume 458 , 2008 , Pages 81-121 ; 10643745 (ISSN); 9781588297181 (ISBN) ; Sharif University of Technology
2008
Abstract
This chapter covers a part of the spectrum of neural-network uses in analytical chemistry. Different architectures of neural networks are described briefly. The chapter focuses on the development of three-layer artificial neural network for modeling the anti-HIV activity of the HETP derivatives and activity parameters (pIC 50) of heparanase inhibitors. The use of a genetic algorithm-kernel partial least squares algorithm combined with an artificial neural network (GA-KPLS-ANN) is described for predicting the activities of a series of aromatic sulfonamides. The retention behavior of terpenes and volatile organic compounds and predicting the response surface of different detection systems are...
Unstable disk galaxies. II. the origin of growing and stationary modes
, Article Astrophysical Journal ; Volume 689, Issue 1 , 2008 , Pages 134-147 ; 0004637X (ISSN) ; Sharif University of Technology
Institute of Physics Publishing
2008
Abstract
I decompose the unstable growing modes of stellar disks to their Fourier components and present the physical mechanism of instabilities in the context of resonances. When the equilibrium distribution function is a nonunifonn function of the orbital angular momentum, the capture of stars into the corotation resonance imbalances the disk angular momentum and triggers growing bar and spiral modes. The stellar disk can then recover its angular momentum balance through the response of nonresonant stars. I carry out a complete analysis of orbital structure corresponding to each Fourier component in the radial angle and present a mathematical condition for the occurrence of van Kampen modes, which...
Novel azo-containing polymethacrylates bearing spiroacetal-norbornene moiety and methylene spacers: synthesis and characterization [electronic resource]
, Article European Polymer Journal ; Volume 37, Issue 10, October 2001, Pages 2111–2121 ; Mirjalili, Bibi Fatemeh ; Entezami, Ali A ; Zohuriaan-Mehr, Mohammad J ; Sharif University of Technology
Abstract
An eight-step synthetic strategy was followed to prepare a series of novel azobenzene-containing methacrylate monomers bearing spiroacetal-norbornene moiety and methylene spacers. Thus, the adduct 2, obtained from cyclopentadiene and acrolein, was converted to 1,3-diol 3. The diol was acetalized with nitrobenzaldehyde 4 under microwave irradiation to obtain nitro compound 5 that was then reduced to amino compound 6. Diazonium salt of 6 was coupled with phenol to produce phenolic compound 7 which was then reacted with n-dibromoalkanes (n=2, 4, 6, 8, 10) to yield bromo compounds 9a–e. Nucleophilic substitution reaction of the bromo compounds with lithium methacrylate produced the methacrylic...
The Application of Chaos Theory and Nonlinear Structures in Financial Time Series
, M.Sc. Thesis Sharif University of Technology ; Modarres Yazdi, Mohammad (Supervisor)
Abstract
Financial and monetary markets are appropriate areas of applying Chaos Theory. Firstly, current theories of financial and monetary economics state that economic and financial variables such as exchange rates and stock prices are stochastic, so forecasting them is almost impossible. Secondly, if we find the hidden ordered and deterministic trends, we can achieve considerable profits. In this piece of research, we evaluate different methods and tests of detecting chaos in financial time series, and choose the most applicable methods to test financial markets’ indices. The main three indices of Tehran Stock Exchange, including Price, Finance and Industry indices, are examined. A sample of the...