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Performance evaluation of Omni-Channel distribution network configurations considering green and transparent criteria under uncertainty
, Article Sustainability (Switzerland) ; Volume 14, Issue 19 , 2022 ; 20711050 (ISSN) ; Khedmati, M ; Akbari Jokar, M. R ; Babaee Tirkolaee, E ; Sharif University of Technology
MDPI
2022
Abstract
Satisfying customer demand is one of the growing concerns of supply chain managers. On the other hand, the development of internet communications has increased online demand. In addition, the COVID-19 pandemic has increased the demand for online shopping. One of the useful concepts that help to address this concern is the omni-channel strategy, which integrates online and traditional channels with the aim of improving customer service level. For this purpose, this paper proposes an algorithm for evaluating Omni-channel Distribution Network Configurations (OCDNCs). The algorithm applies an extended Data Envelopment Analysis (DEA) model to evaluate OCDNCs based on cost, service, transparency,...
Designing an integrated blockchain-enabled supply chain network under uncertainty
, Article Scientific Reports ; Volume 13, Issue 1 , 2023 ; 20452322 (ISSN) ; Khedmati, M ; Akbari Jokar, M. R ; Tirkolaee, E. B ; Sharif University of Technology
Nature Research
2023
Abstract
With the development of communication infrastructure, the design of supply chains has changed significantly. Blockchain technology, as one of the most cutting-edge technologies, can promote transparency among members of the supply chain network. To the best of our knowledge, this is the first study that tries to develop a novel bi-objective optimization model to integrate the transparency resulting from the use of blockchain for designing a three-level supply chain network. The first objective function is to minimize total cost while the second objective function seeks to maximize transparency based on the application of blockchain technology. Moreover, it is worth noting that it is the...
Sustainable transportation planning considering traffic congestion and uncertain conditions
, Article Expert Systems with Applications ; Volume 227 , 2023 ; 09574174 (ISSN) ; Khedmati, M ; Akbari Jokar, M. R ; Babaee Tirkolaee, E ; Sharif University of Technology
Elsevier Ltd
2023
Abstract
Transportation activities, especially road transportation, have a great impact on economic growth. On the other hand, sustainability is a major concern for transportation planning. In this work, a data-oriented network is developed to evaluate the sustainability of vehicle types. Then, this network is integrated with a multi-objective optimization model in order to provide the planning of a three-stage transportation problem, according to traffic congestion. Some criteria including total profit, efficiency of different vehicle types, relationship among the customers supplied by a specified retailer, risk of underestimating unmet demand, and selling price are used to determine the objective...
An integrated decision support system to achieve sustainable development in transportation routes with traffic flow
, Article Environmental Science and Pollution Research ; Volume 30, Issue 21 , 2023 , Pages 60367-60382 ; 09441344 (ISSN) ; Khedmati, M ; Jokar, M. R. A ; Tirkolaee, E. B ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2023
Abstract
Due to the growing population and demand, transportation planning has received special importance in the context of supply chain management. One of the major challenges in transportation planning is the traffic problem. This challenge affects the safety, environmental, and efficiency factors of transportation systems. Accordingly, in this study, the routes, which are important pillars of transportation planning, are examined from the perspective of sustainability. In this regard, a novel decision support system is developed, wherein at first, some decision-making methods including Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), entropy technique, Nash equilibrium...
Evaluation of nutrient removal and biomass production through mixotrophic, heterotrophic, and photoautotrophic cultivation of chlorella in nitrate and ammonium wastewater
, Article International Journal of Environmental Research ; Volume 12, Issue 2 , 2018 , Pages 167-178 ; 17356865 (ISSN) ; Mehrnia, M. R ; Shayegan, J ; Sarrafzadeh, M. H ; Amini, E ; Sharif University of Technology
Springer International Publishing
2018
Abstract
In this study, the effect of mixotrophic, heterotrophic, photoautotrophic (CO2 of air source), and photoautotrophic (bicarbonate source) cultivation of Chlorella vulgaris was investigated on microalgae growth rate and nutrient removal under different kinds of nitrogen sources. The highest N–NH3 +, N–NO3 −, P–PO4 3− (in ammonium source), and P–PO4 3− (in nitrate source) removal efficiency (87.28 ± 0.89, 70.00 ± 1.20, 87.00 ± 3.10, and 78.10 ± 1.95%, respectively) was reached in the mixotrophic culture. In all cultivations, when nitrate was used as the nitrogen source, specific growth rate, biomass productivity, and specific oxygen production rate (SOPR) were higher than the one with ammonium...
Measuring viscoelastic properties of Red Blood Cell using optical tweezers
, Article Iranian Journal of Physics Research ; Volume 19, Issue 1 , 2019 , Pages 101-108 ; 16826957 (ISSN) ; Azadbakht, A ; Mirzahossein, E ; Mottaghian, M ; Babaei, M ; Sharif University of Technology
Isfahan University of Technology
2019
Abstract
Efforts have been made to study the behavior of complex materials in micrometer dimensions with various techniques. One of these methods is the use of optical tweezers for biophysical applications. Red blood cells, as the most abundant blood-forming cells, play an important role in the life of living organisms, and their unique mechanical properties are important. In this report, the study of soft materials is done using light tweezers. This work investigates micrometer particle movements in the optical trap and also, when they are connected to a red blood cell. The tweezers allow the Newtonian fluid viscosity, such as water and glycerin, to measure the mechanical properties of viscoelastic...
Measuring viscoelastic properties of Red Blood Cell using optical tweezers
, Article Iranian Journal of Physics Research ; Volume 19, Issue 1 , 2019 , Pages 101-108 ; 16826957 (ISSN) ; Azadbakht, A ; Mirzahossein, E ; Mottaghian, M ; Babaei, M ; Sharif University of Technology
Isfahan University of Technology
2019
Abstract
Efforts have been made to study the behavior of complex materials in micrometer dimensions with various techniques. One of these methods is the use of optical tweezers for biophysical applications. Red blood cells, as the most abundant blood-forming cells, play an important role in the life of living organisms, and their unique mechanical properties are important. In this report, the study of soft materials is done using light tweezers. This work investigates micrometer particle movements in the optical trap and also, when they are connected to a red blood cell. The tweezers allow the Newtonian fluid viscosity, such as water and glycerin, to measure the mechanical properties of viscoelastic...
Modeling catalyst deactivation in dehydrogenation of ethylbenzene to styrene
, Article 11AIChE - 2011 AIChE Spring Meeting and 7th Global Congress on Process Safety, Conference Proceedings ; 2011 , Pages - ; 9780816910670 (ISBN) ; Baghalha, M ; Sharif University of Technology
American Institute of Chemical Engineers
2011
Abstract
The long-term deactivation of a commercial K-promoted Fe2O3 catalyst used in the dehydrogenation of ethylbenzene to styrene monomer was investigated using 30 mo of operating data of three industrial SM radial fixed bed adiabatic reactors. The Langmuir-Hinshelwood, Hougen-Watson model was used for reaction kinetics modeling. The kinetics of coking from ethylbenzene and styrene and the short-term deactivation function due to the quick coke formation were considered in the model. The kinetics of long-term deactivation of the catalyst for ethylbenzene dehydrogenation to styrene at 550°-630°C were determined. Unknown parameters of the long-term activity function, related to the slow loss of...
Modeling catalyst deactivation in dehydrogenation of ethylbenzene to styrene
, Article AIChE Annual Meeting, Conference Proceedings, 13 March 2011 through 17 March 2011 ; March , 2011 ; 9780816910670 (ISBN) ; Baghalha, M ; Sharif University of Technology
2011
Abstract
Long-term deactivation of a commercial K-promoted Fe 2O 3 catalyst used in the dehydrogenation of ethylbenzene to styrene monomer was studied using 30 months of operating data of three industrial SM radial fixed bed adiabatic reactors. The Langmuir-Hinshelwood, Hougen-Watson model (LHHW) was used for reaction kinetics modeling. The kinetics of coking from ethylbenzene and styrene and the short-term deactivation function due to the quick coke formation were also considered in the model. The kinetics of long-term deactivation of the catalyst for ethylbenzene dehydrogenation to styrene between 550 and 630 °C were determined by allowing the effects of temperature and time on the catalyst...
Effects of temperature and mixing modes on the performance of municipal solid waste anaerobic slurry digester 09 Engineering 0907 Environmental Engineering 09 Engineering 0904 Chemical Engineering
, Article Journal of Environmental Health Science and Engineering ; Volume 17, Issue 2 , 2020 , Pages 1077-1084 ; Shayegan, J ; Sharif University of Technology
Springer
2020
Abstract
Purpose: Anaerobic digestion is a promising technology for simultaneous treatment of biodegradable organic matter of municipal solid waste (MSW) and production of renewable energy. Mixing modes and temperature have influences on biogas production in anaerobic digesters treating MSW. Therefore, in this study, digester was operated at different modes of mixing and temperatures to obtain design criteria. Methods: The experiments were carried out in a semi-continuous digester. In the first part of the investigation, temperature was set at 25, 28, 31 and 34 °C. During this step, digester content was mixed in an intermittent mode by mechanical mixers. In the second part of the study, mixing...
Traffic Source Particle Pollution Distribution Using Micro-scale Simulation
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Vahid (Supervisor)
Abstract
Today air pollution has become one of the major urban management concerns. Air pollution could have dangerous effects on human health in short time or long time in many situations. Numerical modelling is one of the most applicable among different ways for predicting pollutant concentration like field measurement, physical model in wind tunnel, and simulation. Modelling of pollutant dispersion is a way for estimating concentration and aggregation of the pollutant near the surface and with different distances from pollution source. In different dispersion models, one of simplest is the Gaussian model. In this approach it is supposed that emission plume obeys from Gaussian distribution and is...
Point to point Control of a Brachiation Robot Based on Neural Network
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Gholamreza (Supervisor)
Abstract
• Brachiation robot is a kind of under-actuated robots. A brachiating robot is a type of a mobile arm that is capable of moving from branch to branch similar to a long-armed ape. The purpose of this thesis is control of a two link Brachiation robot. The purpose of this thesis is control of a two link Brachiation robot using neural network and geometry control. For this purpose a genetic algorithm based training Neural Network is used to produce a suitable path for the second link of the robot and then using input-output linearization method, the second link is controlled to follow the path. The simulations shows that the Nero Controller designed in this thesis is suitable. The controller can...
Seismic Rehabilitation of Irregular Steel Structures Using Friction Dampers
, M.Sc. Thesis Sharif University of Technology ; Moghaddam, Hassan (Supervisor)
Abstract
The purpose of this study was to find the optimal position and slip force of friction dampers, for improving the seismic performance of regular and irregular steel structures and comparison of dampers final pattern of these buildings.In this regard, one to six floor regular and irregular buildings were designed. These buildings were modeled three-dimensionally in the OpenSees Software, and were subjected to horizontal components of seven far field accelerogram in order to investigate the need for their rehabilitation. The results of the time history analysis of these buildings showed that inter-story drifts exceeds the acceptance criteria which has been assumed 2.5% according to the Life...
Cryptanalysis of a Class of McEliece-like Code-Based Signature Schemes
, M.Sc. Thesis Sharif University of Technology ; Eghlidos, Taraneh (Supervisor)
Abstract
With the advent of quantum computers, the security of cryptographic primitives, including digital signature schemes, has been compromised. Therefore, a kind of signature scheme has been introduced to resist these computers. These schemes are based on hard problems that have so far resisted against quantum computers, known as post-quantum schemes. One group of these schemes is based on the hard problems of coding theory, which are called code-based cryptographic schemes. The first code-based cryptosystem was the McEliece encryption scheme. A number of code-based signature schemes are based on the McEliece encryption scheme. Some of these schemes use three matrices including a non-singular...
Probabilistic tolerance analysis of compliant assemblies
, Article 2007 World Congress, Detroit, MI, 16 April 2007 through 19 April 2007 ; 2007 ; 01487191 (ISSN) ; Movahhedy, M. R ; Sharif University of Technology
SAE International
2007
Abstract
Tolerance analysis is essential for estimation of final error of key product characteristic (KPC) in a mechanical assembly caused by errors in production and assembly of individual parts. Many mechanical assemblies, especially in automotive and aerospace industries, include sheet metal parts with a small ratio of thickness to width or length. Such parts are substantially flexible and thus, are prone to large errors due to elastic deformations during assembly production. Phenomena such as deformation due to fixture force, spring back, welding distortion and so on are common to such parts. Unlike tolerance analysis of rigid parts, here, the elastic deformation of the parts plays a significant...
Fabrication and Characterization of Nickel-Cobalt Catalyst by One-pot Combustion Synthesis Method for Synthesis Gas Production in Dry Reforming Methane Process
, M.Sc. Thesis Sharif University of Technology ; Sadrnezhad, Khatiboleslam (Supervisor)
Abstract
Dry reforming methane is a process during which two greenhouse gases, CH4 and CO2, using Ni-based catalysts, are altered into valuable H2 and CO gases, which are very useful from an economic and environmental point of view. The main problem with Ni-based catalysts is the formation of carbon in the dry methane reforming, which leads to rapid deactivation of the catalyst. In this research, a 10Ni-5Co/Al2O3 bimetallic catalyst was prepared by one-pot microwave-assisted combustion synthesis with a stoichiometric amount of fuel (urea) and without the use of additives. The catalyst was then calcined for 12 h at 550oC. The structure, chemical composition, particle distribution, and morphology of...
Super-hydrophilic characteristic of thermochemically prepared CdS nanocrystals
, Article Physica E: Low-Dimensional Systems and Nanostructures ; Vol. 58 , April , 2014 , pp. 146-152 ; ISSN: 13869477 ; Taghavinia, N ; Babaei, A ; Sharif University of Technology
2014
Abstract
CdS nanocrystals were thermochemically (thermally activated) synthesized thorough the reaction between CdSO4 and Na2S 2O3 in an aqueous solution. Thioglycolic Acid (TGA) was used as the capping agent and catalyst of the reaction. The method was based on heat activated dissociation of Na2S2O3 and controllable release of S and free electrons in the solution. CdS NCs were formed by heating the sample solution at 96 C for 1 h. The results of optical spectroscopy and transmission electron microscopy demonstrated round shape NCs with sizes about 3.0 nm. The nanocrystals were also luminescent and represented a broad emission with a peak located at 515 nm and FWHM of 160 nm. Several samples were...
Cascading failure tolerance of modular small-world networks
, Article IEEE Transactions on Circuits and Systems II: Express Briefs ; Volume 58, Issue 8 , 2011 , Pages 527-531 ; 15497747 (ISSN) ; Ghassemieh, H ; Jalili, M ; Sharif University of Technology
2011
Abstract
Many real-world networks have a modular structure, and their component may undergo random errors and/or intentional attacks. More devastating situations may happen if the network components have a limited load capacity; the errors and attacks may lead to a cascading component removal process, and consequently, the network may lose its desired performance. In this brief, we investigate the tolerance of cascading errors and attacks in modular small-world networks. This brief studies the size of the largest connected component of the networks when cascading errors or attacks occur. The robustness of the network is tested as a function of both the intermodular connection and intramodular...
Byzantine agents' detection in distributed nash equilibrium seeking algorithms using an adaptive event-triggered scheme
, Article IEEE Systems Journal ; Volume 17, Issue 3 , 2023 , Pages 4407-4418 ; 19328184 (ISSN) ; Haeri, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2023
Abstract
In this article, a resilient, adaptive event-triggered distributed Nash equilibrium seeking algorithm is investigated for a class of multimicrogrid systems. Since the strategy of each microgrid affects others' costs through total generation cost, such interaction among microgrids is modeled as a noncooperative game. To reduce unnecessary signal transmission among the aggregators, an adaptive algorithm, where threshold parameters are adjusted based on the behavior of the estimated signals in the last two iterations, is proposed. It is observed that when false data is injected into an agent, its estimated signals begin to diverge from the equilibrium point, and as a result, the threshold value...
Synchronization of Two Chemical Reactors
, M.Sc. Thesis Sharif University of Technology ; Shahrokhi, Mohammad (Supervisor)
Abstract
Chaotic behavior takes place in different physical systems such as chemical reactors. In this thesis, dynamical behavior of chemical reactors in which polymerization or series reactions take place has been considered. It has been shown that these reactors have chaotic dynamics under special condition. Two reactors of the second type (with series reactions) for cases of known and unknown parameters have been synchronized by a control method and stability of the proposed scheme has been established by the Lyapunov stability theorem. Simulation results show the effectiveness of proposed method. Since concentration measurement is difficult and expensive, an observer has been used for...