Loading...
Search for:
arabi--fatemeh
0.098 seconds
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...
Assortment Planning and Pricing with Limited Inventory
, M.Sc. Thesis Sharif University of Technology ; Khedmati, Majid (Supervisor)
Abstract
It has always been a challenge for retailers to plan which of the available goods will be displayed to the customer and at what price for each. In practice, the limited storage capacity of goods, the limited capacity of shelves, or the limited capacity of displaying goods on a web page in online stores may make it more difficult to decide on the above issues. These issues have been addressed in the literature when demand for goods is clear or a good estimate of demand can be obtained based on sales data. The purpose of this study is to investigate multi period Assortment planning, pricing and inventory planning with respect to the limited capacity of storage and display of goods in a...
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...
Preparation of ethyl cellulose microcapsules containing perphenazine and polymeric perphenazine based on acryloyl chloride for physical and chemical studies of drug release control [electronic resource]
, Article Polymer International ; Volume 47, Issue 4, pages 413–418, December 1998 ; Pourjavadi, A ; Hashemi, S. A ; Arabi. , H ; Sharif University of Technology
Abstract
The preparation of microcapsules containing perphenazine by solvent evaporation using ethyl cellulose is described. The microparticles are formed after solvent evaporation and polymer precipitation. The drug was dissolved in a polymer solution and emulsified into an aqueous phase to form microcapsules. To study the effects on particle size, encapsulation efficiency and morphology, three different molecular weights of ethyl cellulose (Mw=47000, 71000 and 99000) were used. Covalent bonding of drugs to polymers via hydrolytically or enzymatically cleavable covalent bond was achieved for sustained drug delivery. The release rate of perphenazine from these systems was investigated
Performance Evaluation of Wireless Network-on-Chips
, M.Sc. Thesis Sharif University of Technology ; Sarbazi Azad, Hamid (Supervisor)
Abstract
On-chip communication infrastructure in chip multiprocessors with large number of processing cores has to be scalable, consumes low power, and provides high bandwidth for hundrededs or even thousands of processing cores. In this project, to this end, the applicability of wireless network technology for on-chip communications in systems with hundreds or thousands of processing elements is investigated. We have combined wired networks (for communication between elements that are close) and wireless networks (for transmition of high volume data flows between cores that are far from each other); so different data flows achive the required bandwidth and point to point delay is reduced. Also, a...
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...
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....
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
Availability optimization of a series system with multiple repairable load sharing subsystems considering redundancy and repair facility allocation
, Article International Journal of Systems Assurance Engineering and Management ; Volume 4, Issue 3 , September , 2013 , Pages 262-274 ; 09756809 (ISSN) ; Eshraghniaye Jahromi, A ; Sharif University of Technology
2013
Abstract
Redundancy technique is considered as a way to enhance the reliability and availability of a system. This paper models availability of a repairable system with multiple subsystems in which the involved components follow the load sharing strategy. In redundancy allocation problems, the redundancy level is just considered, whereas, in this paper, the number of repair facility (repairman) is added to the decision variables. The goal is to find the optimal number of repairmen and redundant components in each subsystem for optimization of availability subject to weight, cost and volume constraints. The main contribution of this study is to present a straightforward model for availability...
Fuzzy analytical hierarchy process using preference ratio: A case study for selecting management short course in a business school
, Article International Journal of Industrial Engineering Computations ; Volume 1, Issue 2 , 2010 , Pages 173-184 ; 19232926 (ISSN) ; Sadi Nezhad, S ; Arabi, F ; Sharif University of Technology
2010
Abstract
Analytic Hierarchy Process (AHP) is one of the most popular approaches in the area of multiple attribute decision making (MADM). However, it is not practical any more if input information are fuzzy. In this paper, we propose a new method for fuzzy AHP which is especially useful to make decisions for multiple attribute problems. The method is developed by applying preference ratio concept which makes it practical since it assigns crisp weights and crisp scores to different alternatives. Two algorithms are proposed in this paper: The first one defines crisp and normalized weight by pairwise comparison with fuzzy data while the second one calculates fuzzy consistency ratio. The proposed method...
Welding metallurgy of duplex stainless steel during resistance spot welding
, Article Welding Journal ; Volume 96, Issue 9 , 2017 , Pages 307s-318s ; 00432296 (ISSN) ; Pouranvari, M ; Movahedi, M ; Sharif University of Technology
2017
Abstract
This paper investigates the metallurgical and mechanical response of 2304 duplex stainless steel-as an interesting candidate for automotive body-in-white applications-to resistance spot welding. The results showed the high cooling rate associated with the resistance spot welding process suppressed the postsolidification ferrite-austenite transformation leading to improper ferrite-austenite phase balance with a reduced volume fraction of austenite and consequent precipitation of chromium-rich nitrides. The effects of welding current, as the key parameter determining the weld heat input, on the austenite volume fraction and precipitation are discussed. The minimum fusion zone hardness...
Pathways to improve the austenite–ferrite phase balance during resistance spot welding of duplex stainless steels
, Article Science and Technology of Welding and Joining ; Volume 24, Issue 1 , 2019 , Pages 8-15 ; 13621718 (ISSN) ; Pouranvari, M ; Movahedi, M ; Sharif University of Technology
Taylor and Francis Ltd
2019
Simulated and experimental investigation of stretch sheet forming of commercial AA1200 aluminum alloy
, Article Transactions of Nonferrous Metals Society of China (English Edition) ; Vol. 24, issue. 2 , February , 2014 , pp. 484-490 ; Khalili, K ; Mohammadsadeghi, B ; Arabi, H ; Sharif University of Technology
2014
Abstract
The simulation and experimental results obtained from stretching test of a commercial sheet of AA1200 aluminum alloy were compared and evaluated. Uniaxial tensile tests were carried out to obtain the required input parameters for simulation. Finite element analysis of the forming process was carried out using Abaqus/Explicit by considering von Mises and Hill-1948 yield criteria. Simulation results including punch force and strain distribution were compared and validated with the experimental results. The results reveal that using anisotropic yield criteria for simulation has a better match in both cases with the experiments
Study on the Phase Transformation and Mechanical Behavior of Duplex Stainless Steel Resistance Spot Welds
, M.Sc. Thesis Sharif University of Technology ; Pouranvari, Majid (Supervisor) ; Movahedi, Mojtaba (Supervisor)
Abstract
Use of materials with both high strength and good formability in car structure is a serious approach in the automotive industry to reduce weight as well as maintain the security of occupants. Stainless steels such as duplex steels are one of the most attractive candidates. Thus, metallurgical and mechanical behavior during resistance spot is important. The aim of this work is to study the microstructure-property relationships in resistance spot welding of duplex stainless steel. Austenite-ferrite phase balance and weld nugget size are two key factors determining the mechanical properties of these steels. High cooling rate of resistance spot welding can have a significant impact on the...
A Survey on Min-cut On Planar Graphs
, M.Sc. Thesis Sharif University of Technology ; Foroughmand Arabi, Mohammad Hadi (Supervisor)
Abstract
In minimum cut problem we aim at finding a set of edges with minimum overall cost possible, such that removing them would separate two specific vertices, source and sink. This problem has been studied thoroughly, however the available algorithms were not proven to be time-wise optimal. Nowadays, planar graphs have attracted more attention because of their applications in cities and countries map. Moreover,their characteristics and properties, make some problems easier to solve in planar case. In this thesis, we will have a survey on algorithms for minimum cut on planar graphs. Our motivation to choose these algorithms is the balance between how easily they could be implemented and how fast...
A Survey on the Steiner Forest Problem
, M.Sc. Thesis Sharif University of Technology ; Foroughmand-Arabi, Mohammad Hadi (Supervisor)
Abstract
The Steiner forest problem is one of the most fundamental issues in network design that emerges in various contexts, such as the design of communication networks,transportation networks, VLSI circuits and phylogenetic network reconstruction. In this problem, we are given a connected weighted undirected graph and a special subset of vertices that are partitioned in pairs. The goal is to fnd a minimum-cost sub-graph in which each special vertex is connected to its mate. In this thesis we review a set of selected solutions for this problem and a few other related problems.For example, we study modeling and solving the s-t shortest path problem in order to gain insight into current Steiner...
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...