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COVID-19 and health inequality: the nexus of race, income and mortality in New York City
, Article International Journal of Human Rights in Healthcare ; 2021 ; 20564902 (ISSN) ; Teron, L ; Rasoulyan, F ; Sharif University of Technology
Emerald Group Holdings Ltd
2021
Abstract
Purpose: The purpose of this paper is to evaluate socioeconomic factors related to COVID-19 mortality rates in New York City (NYC) to understand the connections between socioeconomic variables, including race and income and the disease. Design/methodology/approach: Using multivariable negative binomial regression, the association between health and mortality disparities related to COVID-19 and socioeconomic conditions is evaluated. The authors obtained ZIP code-level data from the NYC Department of Health and Mental Hygiene and the US Census Bureau. Findings: This study concludes that the mortality rate rises in areas with a higher proportion of Hispanic and Black residents, whereas areas...
COVID-19 and health inequality: the nexus of race, income and mortality in New York City
, Article International Journal of Human Rights in Healthcare ; Volume 15, Issue 4 , 2022 , Pages 363-372 ; 20564902 (ISSN) ; Teron, L ; Rasoulyan, F ; Sharif University of Technology
Emerald Group Holdings Ltd
2022
Abstract
Purpose: The purpose of this paper is to evaluate socioeconomic factors related to COVID-19 mortality rates in New York City (NYC) to understand the connections between socioeconomic variables, including race and income and the disease. Design/methodology/approach: Using multivariable negative binomial regression, the association between health and mortality disparities related to COVID-19 and socioeconomic conditions is evaluated. The authors obtained ZIP code-level data from the NYC Department of Health and Mental Hygiene and the US Census Bureau. Findings: This study concludes that the mortality rate rises in areas with a higher proportion of Hispanic and Black residents, whereas areas...
Bilayered heparinized vascular graft fabricated by combining electrospinning and freeze drying methods
, Article Materials Science and Engineering C ; Volume 94 , 2019 , Pages 1067-1076 ; 09284931 (ISSN) ; Shamloo, A ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Small diameter vascular grafts (<6 mm) are highly demanded for patients suffering from severe occluded arteries to be used as a bypass or substituted conduit. Fabricating a graft with appropriate structural, mechanical and cell growth properties which has simultaneously anti-thrombogenic trait is a challenge nowadays. Here, we proposed a bilayer heparinized vascular graft that can mimic the structural and mechanical characteristics close to those of the native coronary artery by combining electrospinning and freeze drying methods. In this study, the inner layer was made by co-electrospinning of synthetic polymer, poly-caprolactone (PCL) and the natural polymer, gelatin (Gel). Also, heparin...
Bilayered heparinized vascular graft fabricated by combining electrospinning and freeze drying methods
, Article Materials Science and Engineering C ; Volume 94 , 2019 , Pages 1067-1076 ; 09284931 (ISSN) ; Shamloo, A ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Small diameter vascular grafts (<6 mm) are highly demanded for patients suffering from severe occluded arteries to be used as a bypass or substituted conduit. Fabricating a graft with appropriate structural, mechanical and cell growth properties which has simultaneously anti-thrombogenic trait is a challenge nowadays. Here, we proposed a bilayer heparinized vascular graft that can mimic the structural and mechanical characteristics close to those of the native coronary artery by combining electrospinning and freeze drying methods. In this study, the inner layer was made by co-electrospinning of synthetic polymer, poly-caprolactone (PCL) and the natural polymer, gelatin (Gel). Also, heparin...
Secure data transmission using qubits
, Article 6th IEEE International Conference on Computer and Information Technology, CIT 2006, Seoul, 20 September 2006 through 22 September 2006 ; 2006 ; 076952687X (ISBN); 9780769526874 (ISBN) ; Hosseini Khayat, S ; Sharif University of Technology
2006
Abstract
A quantum protocol for secure transmission of data using qubits is presented. This protocol sends one qubit in a round-trip to transmit one bit of data. The protocol offers an improvement over the BB84 QKD protocol. BB84, in conjunction with one-time pad encryption, has been shown to be unconditionally secure. However its security relies on the assumption that the qubit source device does not emit multiple replicas of the same qubit for each transmitted bit. If this happens a multi-qubit emission attack can be launched. In addition, BB84 cannot be used to send predetermined bit strings as it generates a random bit string in the process. Our protocol does not have the above drawbacks, but...
Conceptual duct shape design for horizontal-axis hydrokinetic turbines
, Article Scientia Iranica ; Volume 23, Issue 5 , 2016 , Pages 2113-2124 ; 10263098 (ISSN) ; Rad, M ; Khayat, M ; Sharif University of Technology
Sharif University of Technology
2016
Abstract
In the present paper, conceptual duct shape design for kinetic energy extraction with hydrokinetic turbines is discussed. The goal is to find a single-passage axisymmetric geometry that holds stable flow with maximum kinetic energy flux at duct throat. For finding the optimum duct shape, the fluid flow was numerically simulated in a wedge shaped space with Flow-Simulation Software. In a multi-stage conceptual design, tabulated configurations were employed to study each geometrical characteristic separately. These include curvature of profile camber, trailing edge shape, profile tip shape, and duct exit cross sectional area. The revolved profile of each duct consists of a well constrained...
Design and Fabrication of Engineered Biomaterials for Tissue Engineering Applications such as Cardiovascular System
, M.Sc. Thesis Sharif University of Technology ; Shamlou, Amir (Supervisor)
Abstract
Cardiovascular diseases are the leading cause of death all over the world, even more common than cancers. The first reason of mortality in Iran according to statistics is the occlusion of coronary arteries. Unfortunately almost one third of patients doesn’t have enough blood vessels to be used in the bypass surgery and need artificial vessels. These artificial blood vessels with small diameters (less than 6 mm) will fail quickly. As a result there is an increasing demand for tissue engineered blood vessels which are capable of enduring high blood pressures. An artificial blood vessel should mimic both structure and mechanical properties of the real one. Blood vessels have layered structures,...
Numerical and experimental investigations for design of a high performance microhydro-kinetic turbine
, Article International Journal of Engineering, Transactions B: Applications ; Volume 30, Issue 5 , 2017 , Pages 785-790 ; 1728144X (ISSN) ; Rad, M ; Khayat, M ; Sharif University of Technology
2017
Abstract
Design and manufacturing of a high performance micro-hydro-kinetic turbine is discussed in the present paper. The main goal is manufacturing an equipped experimental model of hydro-kinetic turbine with highest energy absorption from water current. A multi-shape ducted turbine comprised of a multi-part diffuser was manufactured that can be converted to many experimental models for studying various diffuser enhancing effects. Turbine's rotor included a three-blade axial propeller and a mixed six-blade propeller with high power coefficient. Simple experiments on propeller were performed for flow visualization, torque measurement and illustrating dynamic balance at high speed rotation in air and...
Experimental and numerical investigations of a single turn pulsating heat pipe using distilled water including micro-coppers
, Article Heat and Mass Transfer/Waerme- und Stoffuebertragung ; Volume 59, Issue 9 , 2023 , Pages 1601-1619 ; 09477411 (ISSN) ; Zareh, M ; Shafii, M. B ; Khayat, M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2023
Abstract
In this work, experimental and numerical investigations were performed to evaluate the heat transfer efficiency of a single turn pulsating heat pipe by using distilled water as base fluid and distilled water with micro particles (micro-coppers). The pulsating heat pipe was manufactured with copper capillary tube by choosing the internal and external diameter 4 mm and 6 mm, respectively. The effect of filling ratio (40, 50 and 60%), heat input (20, 30, 40, 50 and 60 W) and concentrations of micro-coppers (0.0625 g ml−1 and 0.125 g ml−1) in distilled water as base fluid were studied. Experimental findings displayed that the thermal resistance of the system using micro-coppers declined with...
Prediction of hydrate formation for the systems containing single and mixed electrolyte solutions
, Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 26, Issue 1 , 2007 , Pages 35-45 ; 10219986 (ISSN) ; Rashtchian, D ; Ghotbi, C ; Taghikhani, V ; Khayat, G ; Sharif University of Technology
Iranian Journal of Chemistry and Chemical Engineering
2007
Abstract
In this work the effect of electrolytes on hydrate formation was investigated. To do so, a new model was used in predicting the hydrate formation conditions in presence of both single and mixed electrolyte solutions. The new model is based on the van der Waals - Platteeuw hydrate equation of state. In order to evaluate the values for the activity of water in electrolyte solutions the simplified version of the Ghotbi-Vera Mean Spherical Approximation (SGV-MSA) model was used. According to the SGV-MSA model the ions in the solutions are considered as charged hard spheres with different sizes. The values of the parameters for the SGV-MSA model are independent of temperature and depend only on...
A novel hybrid algorithm for creating self-organizing fuzzy neural networks
, Article Neurocomputing ; Volume 73, Issue 1-3 , 2009 , Pages 517-524 ; 09252312 (ISSN) ; Ebadzadeh, M. M ; Shahdoosti, H. R ; Rajaei, R ; Khajehnasiri, I ; Sharif University of Technology
2009
Abstract
A novel hybrid algorithm based on a genetic algorithm and particle swarm optimization to design a fuzzy neural network, named self-organizing fuzzy neural network based on GA and PSO (SOFNNGAPSO), to implement Takagi-Sugeno (TS) type fuzzy models is proposed in this paper. The proposed algorithm, as a new hybrid algorithm, consists of two phases. A tuning based on TS's fuzzy model is applied to identify the fuzzy structure, and also a fuzzy cluster validity index is utilized to determine the optimal number of clusters. To obtain a more precision model, GA and PSO are performed to conduct fine tuning for the obtained parameter set of the premise parts and consequent parts in the...
Effect of heating profile on desorption curve in temperature programmed desorption analysis: Case study of acid sites distribution of SAPO-34
, Article Journal of Porous Materials ; Volume 16, Issue 5 , 2009 , Pages 599-603 ; 13802224 (ISSN) ; Farhadi, F ; Khorasheh, F ; Yan, Z. F ; Sharif University of Technology
2009
Abstract
Comparison of the traditional linear heating method of TPD with an original stepwise heating scheme was reported for the first time. Stepwise heating TPD was carried out by keeping the temperature constant as soon as ammonia desorption signal rises until the signal returns to the baseline. More ammonia desorption peaks on a SAPO-34 catalyst were identified using TPD with stepwise heating. The effect of temperature ramp on desorption peak broadening in TPD curve was also addressed. The more distinct ammonia desorption peaks in stepwise TPD indicates that ammonia adsorbs in about five or six different ways on SAPO-34, and attribution of different adsorptions may be explained considering some...
Theoretical and experimental study of cascade solar stills
, Article Solar Energy ; Volume 90 , April , 2013 , Pages 205-211 ; 0038092X (ISSN) ; Sharak, A. Z ; Moghadam, H ; Tabrizi, F. F ; Sharif University of Technology
2013
Abstract
Most part of Iran is dominated by arid and semi-arid areas due to low annual rainfall. The need for production of fresh water from brackish water is considerably high, especially in dry regions. In this study 1 month daily-based experimental data from a solar still site has been reported. The technical and operational problems of this site which finally contributed to the total cease of the site are described. Then a detailed analysis is investigated on progress of a prototype which constructed in order to solve the site's problems. The results of 1 month of experimental data of the final design showed that the last prototype could be used to solve the current problems of the site. The...
Application of a continuous kinetic model for the hydrocracking of vacuum gas oil
, Article Petroleum Science and Technology ; Vol. 32, Issue. 18 , 2014 , Pages 2245-2252 ; ISSN: 10916466 ; Khorasheh, F ; Farhadi, F ; Sharif University of Technology
2014
Abstract
Hydrocracking is one of the most versatile petroleum refining processes for production of valuable products including gasoline, gas oil, and jet fuel. In this paper, a five-parameter continuous lumping model was used for kinetic modeling of hydrocracking of vacuum gas oil (VGO). The model parameters were estimated from industrial data obtained from a fixed bed reactor operating at an average temperature of 400°C and residence time of 0.3 h. Product distributions were obtained in terms of the weight fraction of various boiling point cuts. The model parameters were estimated using the Nelder-Mead optimization procedure and were correlated with temperature. Comparison of experimental and...
An improved methodology for design of custom-made hip prostheses to be fabricated using additive manufacturing technologies
, Article Rapid Prototyping Journal ; Volume 18, Issue 5 , 2012 , Pages 389-400 ; 13552546 (ISSN) ; Abbaszadeh, F ; Farahmand, F ; Sharif University of Technology
Emerald
2012
Abstract
Purpose - The purpose of this paper is to present an improved methodology for design of custom-made hip prostheses, through integration of advanced image processing, computer aided design (CAD) and additive manufacturing (AM) technologies. Design/methodology/approach - The proposed methodology for design of custom-made hip prostheses is based on an independent design criterion for each of the intra-medullary and extra-medullary portions of the prosthesis. The intra-medullar part of the prosthesis is designed using a more accurate and detailed description of the 3D geometry of the femoral intra-medullary cavity, including the septum calcar ridge, so that an improved fill and fit performance...
Evaluation and enhancing of operational performance and training objective in accordance with Line Operations Safety Audit (LOSA)
, Article International Air Safety Seminar Proceedings, 1 November 2011 through 3 November 2011 ; November , 2011 , Pages 78-99 ; 02705176 (ISSN) ; 9781618393975 (ISBN) ; Goodarzi, F ; Sharafbafi, F ; Sharif University of Technology
2011
Real-time impulse noise suppression from images using an efficient weighted-average filtering
, Article IEEE Signal Processing Letters ; Volume 22, Issue 8 , 2015 , Pages 1050-1054 ; 10709908 (ISSN) ; Hessar, F ; Marvasti, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
In this letter, we propose a method for real-time high density impulse noise suppression from images. In our method, we first apply an impulse detector to identify the corrupted pixels and then employ an innovative weighted-average filter to restore them. The filter takes the nearest neighboring interpolated image as the initial image and computes the weights according to the relative positions of the corrupted and uncorrupted pixels. Experimental results show that the proposed method outperforms the best existing methods in both PSNR measure and visual quality and is quite suitable for real-time applications
Kinetic modeling of pyrolysis of scrap tires
, Article Journal of Analytical and Applied Pyrolysis ; Volume 84, Issue 2 , 2009 , Pages 157-164 ; 01652370 (ISSN) ; Farhadi, F ; Khorasheh, F ; Sharif University of Technology
2009
Abstract
The disposal of used tires is a major environmental problem. With increasing interest on recovery of wastes, pyrolysis is considered as an alternative process for recovering some of the value in scrap tires. An accurate kinetic model is required to predict product yields during thermal or catalytic pyrolysis of scrap tires. Pyrolysis products contain a variety of hydrocarbons over a wide boiling range. A common approach for kinetic modeling of such complex systems is lumping where each lump is defined by a boiling point range. Available experimental data for thermal and catalytic pyrolysis of scrap tires from the literature were used to evaluate two types of lumping models; discrete and...
Determine oil content in petroleum waxes
, Article Hydrocarbon Processing ; Volume 85, Issue 6 , 2006 , Pages 95-97 ; 00188190 (ISSN) ; Yazdani, F ; Farhadi, F ; Sharif University of Technology
2006
Analytical modeling of variable-reluctance tubular resolver based on magnetic equivalent circuit and conformal mapping
, Article IEEE Transactions on Instrumentation and Measurement ; Volume 70 , 2021 ; 00189456 (ISSN) ; Zare, F ; Tootoonchian, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
Compared with flat linear structures, tubular linear machines do not face edge effects, making their performance better than their flat counterparts. In this article, a novel linear variable-reluctance resolver with tubular configuration is proposed. To optimize the design of an electromagnetic structure, modeling methods are used. Thus, in this article, an analytical model for the proposed resolver is presented. This model is based on the magnetic equivalent circuit (MEC) method and is considerably less time-consuming than finite element analysis (FEA), yet provides accurate results. A conformal mapping is employed to compute the permeance of the air-gap. The proposed model is then utilized...