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responsive-surfaces
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Robust estimation of multi-response surfaces considering correlation structure
, Article Communications in Statistics - Theory and Methods ; Vol. 43, issue. 22 , Oct , 2014 , p. 4749-4765 ; Bashiri, M ; Niaki, S. T. A ; Sharif University of Technology
Abstract
Response surfaces express the behavior of responses and can be used for both single and multi-response problems. A common approach to estimate a response surface using experimental results is the ordinary least squares (OLS) method. Since OLS is very sensitive to outliers, some robust approaches have been discussed in the literature. Although there are many methods available in the literature for multiple response optimizations, there are a few studies in model building especially robust models. Assuming correlated responses, in this paper, a robust coefficient estimation method is proposed for multi response problem based on M-estimators. In order to illustrate the performance of the...
Design and fabrication of conductive nanofibrous scaffolds for neural tissue engineering: Process modeling via response surface methodology
, Article Journal of biomaterials applications ; Volume 33, Issue 5 , 2018 , Pages 619-629 ; 15308022 (ISSN) ; Mashayekhan, S ; Baniasadi, H ; Ramazani, A ; Ansarizadeh, M ; Sharif University of Technology
NLM (Medline)
2018
Abstract
Peripheral nervous system in contrary to central one has the potential for regeneration, but its regrowth requires proper environmental conditions and supporting growth factors. The aim of this study is to design and fabricate a conductive polyaniline/graphene nanoparticles incorporated gelatin nanofibrous scaffolds suitable for peripheral nervous system regeneration. The scaffolds were fabricated with electrospinning and the fabrication process was designed with Design-Expert software via response surface methodology. The effect of process parameters including applied voltage (kV), syringe pump flow rate (cm3/h), and PAG concentration (wt%), on the scaffold conductivity, nanofibers diameter,...
Suppressed acrylamide formation during baking in yeast-leavened bread based on added asparaginase, baking time and temperature using response surface methodology
, Article Applied Food Biotechnology ; Volume 5, Issue 1 , 2018 , Pages 29-36 ; 23455357 (ISSN) ; Alemzadeh, I ; Sharif University of Technology
National Nutrition and Food Technology Research Institute
2018
Abstract
Background and Objective: Acrylamide as a toxic substance for human beings is produced by Maillard reaction at high temperatures. In this research, this reaction can be inhibited based on using aspariganse enzyme, controlling the cooking time and temperature during baking in yeast-leavened bread. Materials and Methods: In this study, a response surface methodology 5-level-3-factor central composite design was applied to study the effects of asparaginase (300-900 U Kg-1 of flour), baking temperature (230-280°C) and baking time (13-16 min) on acrylamide formation in yeast-leavened wheat bread. Results and Conclusion: Added asparaginase showed a reducing effect on acrylamide formation...
Adsorption and oxidation of dye and tetracycline over hydrothermally synthesized polyresorcinol – Ferrite nanoparticles
, Article Desalination and Water Treatment ; Volume 212 , 2021 , Pages 376-389 ; 19443994 (ISSN) ; Alijani, H ; Hossein Beyki, M ; Jafari Pirouz, M ; Sharif University of Technology
Desalination Publications
2021
Abstract
This study focuses on developing an efficient material that integrates high adsorption performances of dye and antibiotics as well as effective oxidation activity of it. Herein, we report a facile method to synthesize polyresorcinol@CoFe2 O4 via a one-step hydrothermally route. The prepared composite possesses multifunctional performance for methylene blue (MB) and tetracycline (TC) removal with appropriate magnetic separation operation and significant removal ability with an adsorption capacity of 51.48 and 28.16 mg g–1, respectively. Meanwhile, the aforementioned composite exhibits a high oxidation activity toward MB and TC molecules where the adsorption capacity increases to 1,723 and 120...
Xylanase production under solid state fermentation by aspergillus niger
, Article International Journal of Engineering, Transactions B: Applications ; Volume 24, Issue 3 , March , 2011 , Pages 197-208 ; 1728-144X (ISSN) ; Alemzadeh, I ; Khanahmadi, M ; Roostaazad, R ; Sharif University of Technology
Materials and Energy Research Center
2011
Abstract
Central composite orthogonal design was applied to quantify relations of xylanase production, loss of dry matter and change of pH with four critical variables during solid state fermentation of a mixture of wheat bran and wheat straw on which Aspergillus niger CCUG 33991 was cultivated. The studied variables included the percentage of wheat straw, wheat bran, temperature, moisture content, and fermentation time. The second-order quadratic model predicted the xylanase activity at a suitable set of conditions namely 29°C, 55% moisture content, and 50 hours of fermentation to be 1465 U/g of fermented dry matter which differed less than 6% from measured value at this set of conditions....
Biodegradation of cyanide by a new isolated strain under alkaline conditions and optimization by response surface methodology (RSM)
, Article Journal of Environmental Health Science and Engineering ; Vol. 12, issue. 1 , 2014 ; Yaghmaei, S ; Nejad, Z. G ; Sharif University of Technology
Abstract
Background: Biodegradation of free cyanide from industrial wastewaters has been proven as a viable and robust method for treatment of wastewaters containing cyanide. Results: Cyanide degrading bacteria were isolated from a wastewater treatment plant for coke-oven-gas condensate by enrichment culture technique. Five strains were able to use cyanide as the sole nitrogen source under alkaline conditions and among them; one strain (C2) was selected for further studies on the basis of the higher efficiency of cyanide degradation. The bacterium was able to tolerate free cyanide at concentrations of up to 500 ppm which makes it a good potentially candidate for the biological treatment of cyanide...
Comparative photodecolorization of red dye by anatase, rutile (TiO 2), and wurtzite (ZnO) using response surface methodology
, Article Turkish Journal of Chemistry ; Volume 36, Issue 1 , 2012 , Pages 121-135 ; 13000527 (ISSN) ; Sadrnezhaad, S. K ; Rad, M. K ; Üner, D ; Sharif University of Technology
2012
Abstract
Treatment of dye pollution containing C.I. Acid Red 14 (AR14) by a coupled photocatalytic process was studied. Titanium dioxide, in the form of anatase and rutile, and zinc oxide, were used as photocatalysts. The investigated photocatalysts were Aldrich-produced nanopowders with crystallites of a mean size of 20-30 nm and a specific surface area of about 50 m 2/g. A comparison of TiO 2(anatase), TiO 2(rutile), TiO 2(a,r), and ZnO for the decolorization of the AR14 solution was performed. Results showed that color removal followed the decreasing order of TiO 2(a,r), ZnO > TiO 2(a,r) > TiO 2(a), ZnO > TiO 2(r), ZnO >TiO 2(a,r) > TiO 2(a) > ZnO > TiO 2(r). Response surface methodology (RSM) was...
Optimization of catalytic activity of sulfated titania for efficient synthesis of isoamyl acetate by response surface methodology
, Article Monatshefte fur Chemie ; Volume 146, Issue 12 , December , 2015 , Pages 1949-1957 ; 00269247 (ISSN) ; Sadehvand, M ; Azad, A ; Dekamin, M. G ; Jalali Heravi, M ; Mollahosseini, A ; Amani, M ; Tadjarodi, A ; Sharif University of Technology
Springer-Verlag Wien
2015
Abstract
TiO2 nanoparticles were synthesized by sol-gel method using titanium tetraisopropoxide. Sulfate ions were introduced on the titania by impregnation method using sulfuric acid as precursor of sulfate ions. Fourier transform infrared and energy-dispersive X-ray spectroscopy, X-ray fluorescence as well as X-ray diffraction, scanning electron microscopy, and BET methods were used for the characterization of the obtained nanoparticles. The esterification of isoamyl alcohol with acetic acid was investigated to prove the catalytic activity of the TiO2 nanoparticles under solvent-free conditions. Response surface methodology was applied to optimize the effect of some parameters such as the molar...
Process optimization and modeling of anaerobic digestion of cow manure for enhanced biogas yield in a mixed plug-flow reactor using response surface methodology
, Article Biosciences Biotechnology Research Asia ; Volume 12, Issue 3 , 2015 , Pages 2333-2344 ; 09731245 (ISSN) ; Ajabshirchi, Y ; Mousavi, S. M ; Nosrati, M ; Yaghmaei, S ; Sharif University of Technology
Oriental Scientific Publishing Company
2015
Abstract
Pilot scale experiments were performed on the digestion of dairy cow manure in a semi-continuous process using a mixed plug flow reactor (MPFR) to determine the effects of organic loading rate (OLR), temperature and mixing levels on production biogas and methane yield. Response surface methodology (RSM) was applied for the design and analysis of experiments with the optimization of OLR, temperature and mixing level during the biogas production process. Experiments were designed as per the central composite design technique. Four cubic mathematical models were derived for prediction of the responses. The optimization study has been carried out to identify the highest yields achievable when...
High flux electrospun nanofiberous membrane: Preparation by statistical approach, characterization, and microfiltration assessment
, Article Revista Mexicana de Urologia ; Volume 76, Issue 1 , 2016 , Pages 474-483 ; 01854542 (ISSN) ; Mousavi, S. A ; Bastani, D ; Sharif University of Technology
Elsevier Doyma Mexico
2016
Abstract
Preparation, characterization and evaluation of new generation of micro-filters based on polyacrylonitrile electrospun nanofiberous membrane (ENM) were thoroughly investigated. First, quantitative relationships between average diameter, bead area density of nano-fibers and certain electrospinning parameters, i.e., concentration, voltage, spinning distance, and feed rate, were established by empirical modeling based on a central composite design. The analysis revealed that concentration, voltage and distance are the significant parameters. Also, adequacy checking indicated the appropriateness of fit for the models. Afterwards, bead-free ENMs with diameter of 100-500 nm were prepared and...
Enzymatic synthesis of theanine in the presence of L-glutaminase produced by Trichoderma koningii
, Article Applied Food Biotechnology ; Volume 4, Issue 2 , 2017 , Pages 113-121 ; 23455357 (ISSN) ; Alemzadeh, I ; Sharif University of Technology
National Nutrition and Food Technology Research Institute
2017
Abstract
Background and Objective: Since ancient times, it has been said that drinking green tea brings relaxation. The substance that is responsible for a sense of relaxation is theanine. Theanine (γ-glutamylethylamide) is a unique non-protein amino acid. It gives an umami taste and a unique flavor to the tea, and has many physiological and pharmaceutical effects such as anti-tumor, anti-cancer, neuro-protective, anti-hypertensive and anti-obesity effects; it may further help in relaxation and increase focus. So this compound is essential for human body; however, it is not synthesized in the body and should be administrated orally. In the present study, the enzymatic biosynthesis of theanine was...
Humic acid removal from water using a novel fabricated antifouling carbon nanotube bucky - paper membrane and effect of operating parameters
, Article Global Nest Journal ; Volume 19, Issue 2 , 2017 , Pages 217-224 ; 17907632 (ISSN) ; Nasseri, S ; Nabizadeh, R ; Mousavi, S. A ; Rezaee, R ; Mahvi, A. H ; Sharif University of Technology
Global NEST
2017
Abstract
In present work, a novel supported bucky paper (BP) membrane was fabricated and evaluated for humic acid (HA) removal from water. For better understanding the effect of operating variables, response surface methodology (RSM) was also applied. Three independent parameters namely TOC concentration (5, 10 and 15 mg l-1), operating time (10, 20 and 30 min) and transmembrane pressure (TMP) (1, 2 and 3 bar) were selected for TOC removal (%) and permeate flux analysis. The results revealed that the membrane could effectively remove HA primarily through electrostatic repulsion and then adsorption mechanisms. The study also showed that about 65% and 35% of the removed HA were through repulsion and...
Multidisciplinary optimisation of a car component under NVH and weight constraints using RSM
, Article International Journal of Vehicle Noise and Vibration ; Volume 5, Issue 3 , 2009 , Pages 261-270 ; 14791471 (ISSN) ; Azadi, S ; Moradi, M ; Zahedi, F ; Sharif University of Technology
2009
Abstract
One of the important challenges in the auto industry is to reduce the mass of the vehicle while meeting structural performance requirements for crashworthiness, noise, vibration and harshness, etc. In this paper, a multidisciplinary optimisation of a car back-bonnet is investigated by using the response surface method. A car body is fully surface modelled in CATIA and meshed in software. Then, modal analysis of the finite element model is performed by NASTRAN software to find natural frequencies. A frequency map of that component is extracted and compared with a reference map to detect defects. Design of experiments methodology is used for a screening of the design space and for the...
Superparamagnetic enzyme-graphene oxide magnetic nanocomposite as an environmentally friendly biocatalyst: Synthesis and biodegradation of dye using response surface methodology
, Article Microchemical Journal ; Volume 145 , 2019 , Pages 547-558 ; 0026265X (ISSN) ; Borghei, S. M ; Mahmoodi, N. M ; Sharif University of Technology
Elsevier Inc
2019
Abstract
The unique properties of graphene oxide (GO) nanosheets were integrated with the superparamagnetic characteristics of the CuFe2O4 nanoparticles to synthesize the magnetic graphene oxide (MGO), which was chemically modified with 3-amino propyl trimethoxy silane (APTMS) to functionalize the amine group on MGO (MGO-NH2). Afterward, MGO-NH2 was activated with glutaraldehyde (GLU) as a crosslinking agent to synthesize the functionalized MGO (fMGO) and its capability toward covalent Laccase immobilization was investigated. The comprehensive structural analysis using various characterization techniques, including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), vibrating...
L-sorbose production by gluconobacter oxydans using submerged fermentation in a bench scale fermenter
, Article Applied Food Biotechnology ; Volume 7, Issue 1 , 2020 , Pages 41-48 ; Alemzadeh, I ; Sharif University of Technology
National Nutrition and Food Technology Research Institute
2020
Abstract
Background and objective: L-Sorbose, as a precursor of ascorbic acid, can be biologically produced using Gluconobacter oxydans. The aim of this study was to optimize production of L-Sorbose by controlling concentration of the substrates and starter cultures. Material and methods: In this study, effects of three various fermentation parameters on the concentration of L-sorbose were assessed using fermenter (28°C, 1.4 vvm) and response surface methodology. These parameters included quantities of D-sorbitol (120-180 g lDw-1) (Deionized water) and yeast extract (6-18 g lDw-1) and inoculum/substrate ratios (5-10%). Results and conclusion: Results showed that the fitted model with high values of...
Biodegradation of 4-chlorobenzoic acid by lysinibacillus macrolides DSM54T and determination of optimal conditions
, Article International Journal of Environmental Research ; Volume 14, Issue 2 , 2020 , Pages 145-154 ; Sharifi, H ; Ghobadi Nejad, Z ; Hasan Zadeh, A ; Yaghmaei, S ; Sharif University of Technology
Springer
2020
Abstract
Chlorobenzoic acids (CBAs) are recalcitrant and toxic materials which enter the environment directly using pesticides and herbicides, or indirectly through the biodegradation of polychlorinated biphenyl (PCB) compounds. In the conducted study, biodegradation of 4-chlrobenzoic acid was investigated by Lysinibacillus macrolides DSM54T, which had previously been isolated from PCB-polluted soils. Environmental factors including pH, temperature, 4-CBA concentration and inoculation percentage were optimized using response surface methodology (RSM). 58 experiments were designed according to Historical Data, because of the arbitrary selection of experiments, and the combined effects of the...
A robust multi-objective optimization model for project scheduling considering risk and sustainable development criteria
, Article Environment, Development and Sustainability ; Volume 23, Issue 8 , 2021 , Pages 11494-11524 ; 1387585X (ISSN) ; Abbasianjahromi, H. R ; Sepehri, M ; Zeighami, E ; Sharif University of Technology
Springer Science and Business Media B.V
2021
Abstract
There is limited research that considers the sustainability aspect of the projects’ schedule. The present study proposes a model to cover this gap by considering sustainable development criteria. A multi-objective model with four objective functions, including minimizing cost, risk, and socio-environmental impacts, has been presented to decrease the project’s delay. Since some of the parameters are considered under conditions of uncertainty for the proximity of problems to real projects, the robust programming method is used to deal with the uncertainty, and the epsilon-constraint method was applied to solve the multi-objective model. Several scenarios are also defined to analyze the...
Synthesis of Ni-Co-CNT nanocomposite and evaluation of its photocatalytic dye (Reactive red 120) degradation ability using response surface methodology
, Article Desalination and Water Treatment ; Volume 216 , 2021 , Pages 389-400 ; 19443994 (ISSN) ; Seifpanahi Shabani, K ; Mahmoodi, B ; Mahmoodi, N. M ; Khorasheh, F ; Baghalha, M ; Sharif University of Technology
Desalination Publications
2021
Abstract
Herein, NiO and Co2 O3, NiCo2 O4, and NiCo2 O4 /multi-walled carbon nanotubes nanocomposite were synthesized by the hydrothermal method and characterized by scanning electron micros-copy, energy dispersive spectroscopy, and X-ray diffraction. The photocatalytic activity of the synthesized materials was evaluated by Reactive Red 120 dye degradation. The photocatalytic activity of NiO and Co3 O4 was enhanced not only by the formation of NiCo2 O4, but also by its interaction with the functionalized multiwall carbon nanotubes support. The response surface methodology (RSM) was used to obtain the optimum parameters, including catalyst dosage, initial dye concen-tration, and pH on the dye...
Design optimisation of aluminium recycling processes using Taguchi technique
, Article Journal of Materials Processing Technology ; Volume 127, Issue 1 , 2002 , Pages 96-106 ; 09240136 (ISSN) ; Masters, I ; Gethin, D. T ; Sharif University of Technology
2002
Abstract
In this paper, a robust design method is developed for reducing cost and improving quality in aluminium recycling. An experimental investigation into the process parameter effects is presented to determine the optimum configuration of design parameters for performance, quality and cost. The Taguchi method is applied initially to plan a minimum number of experiments. Orthogonal array techniques are used to investigate the simultaneous variation of several parameters and the investigation of interactions between parameters. Matrix experiments using standard L4 and L9 orthogonal arrays are employed to evaluate the effects of parameters in recycling of aluminium dross and scrap materials. A...
Prediction of concrete compressive strength using a back-propagation neural network optimized by a genetic algorithm and response surface analysis considering the appearance of aggregates and curing conditions
, Article Buildings ; Volume 12, Issue 4 , 2022 ; 20755309 (ISSN) ; Amiri, N ; Ghorbani, S ; Souri, K ; Sharif University of Technology
MDPI
2022
Abstract
In the present research, the authors have attempted to examine the compressive strength of conventional concrete, which is made using different aggregate sizes and geometries considering various curing temperatures. To this end, different aggregate geometries (rounded and angular) were utilized in various aggregate sizes (10, 20, and 30 mm) to prepare 108 rectangular cubic specimens. Then, the curing process was carried out in the vicinity of wind at different temperatures (5◦ C < T < 30◦ C). Next, the static compression experiments were performed on 28-day concrete specimens. Additionally, each test was repeated three times to check the repeatability of the results. Finally, the mean...