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A new pipeline implementation of an adaptive IIR filter for noise reduction application
, Article IEEE International Symposium on Communications and Information Technologies: Smart Info-Media Systems, ISCIT 2004, Sapporo, 26 October 2004 through 29 October 2004 ; Volume 1 , 2004 , Pages 577-581 ; 0780385934 (ISBN) ; Manzuri, M. T ; Ayat, S ; Sharif University of Technology
2004
Abstract
the parallel form in adaptive HR filtering is an efficient realization that provides robust stability monitoring with less complexity than that of the direct form. This paper presents an implementation of two line parallel structure employing a real orthogonal transform and real coefficients second-order section as sub filters on FPGA. Architecture that is implemented is in pipeline fashion and it is independent from its building blocks and they may have its own implementation or in other system numbering. In the last section, we compared throughput of our architecture with a Ti DSP (TMS320C3x/4x), the results show that this architecture works better than the DSP
A compact model for predicting road traffic noise
, Article Iranian Journal of Environmental Health Science and Engineering ; Volume 6, Issue 3 , 2009 , Pages 181-186 ; 17351979 (ISSN) ; Abbaspour, M ; Nassiri, P ; Mahjub, H ; Sharif University of Technology
2009
Abstract
Noise is one of the most important sources of pollution in the metropolitan areas. The recognition of road traffic noise as one of the main sources of environmental pollution has led to develop models that enable us to predict noise level from fundamental variables. Traffic noise prediction models are required as aids in the design of roads and sometimes in the assessment of existing, or envisaged changes in, traffic noise conditions. The purpose of this study was to design a prediction road traffic noise model from traffic variables and conditions of transportation in Iran. This paper is the result of a research conducted in the city of Hamadan with the ultimate objective of setting up a...
Fabrication of MEA based on sulfonic acid functionalized carbon supported platinum nanoparticles for oxygen reduction reaction in PEMFCs
, Article RSC Advances ; 2015 , Pages 85775-85784 ; 20462069 (ISSN) ; Yasi, F ; Kazemeini, M ; Heydari, A ; Golmohammadi, F ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
The Nafion ionomer affects the efficiency of the platinum (Pt) catalyst by blocking the active sites thereby restricting the gas permeability of the catalyst layer; but, there is a limitation in the quantity of Nafion ionomer that needs to be added without affecting the cell performance. Sulfonation of carbon-supported catalysts as mixed electronic and protonic conductors has been reported to be an efficient way to increase the triple-phase boundaries. In order to improve the utilization and activity of cathodic catalysts in the oxygen reduction reaction (ORR), Pt nanoparticles were loaded on a mixture of Vulcan XC-72R and MWCNTs, which were functionalized in a mixture of 96% sulfuric acid...
A framework for multi-objective optimisation of 3D part-build orientation with a desired angular resolution in additive manufacturing processes
, Article Virtual and Physical Prototyping ; Volume 14, Issue 1 , 2019 , Pages 19-36 ; 17452759 (ISSN) ; Khodaygan, S ; Sharif University of Technology
Taylor and Francis Ltd
2019
Abstract
In additive manufacturing processes, the part build orientation (PBO) is one of the most important factors that can affect the characteristics of the quality product such as the amount of support structure and the surface roughness. In most previous methods, the optimal PBO cannot be determined with high precision and accuracy in 3D space. In this paper, to find the precise and accurate optimal PBO with a desired angular accuracy, a new Taguchi-based method, called the Zooming-Taguchi method, is proposed. The proposed simulation-based method can precisely find the optimal PBO in absence of the noise effects. In order to find the optimal PBO with the desired angular resolution, the zooming...
The effect of microthread design on magnitude and distribution of stresses in bone: a three-dimensional finite element analysis
, Article Dental Research Journal ; Volume 15, Issue 5 , 2018 , Pages 347-353 ; 17353327 (ISSN) ; Eskandari, A ; Movahhedy, M. R ; Shirmohammadi, A ; Amid, R ; Sharif University of Technology
2018
Abstract
Background: The researches regarding the influence of microthread design variables on the stress distribution in bone and a biomechanically optimal design for implant neck are limited. The aim of the present study is to compare the effect of different microthread designs on crestal bone stress. Materials and Methods: Six implant models were constructed for three-dimensional finite element analysis including two thread profile (coarse and fine) with three different lengths of microthreaded neck (1 mm, 2 mm, and 3 mm). A load of 200 N was applied in two angulations (0° and 30°) relative to the long axis of the implant and the resultant maximum von Mises equivalent (EQV), compressive, tensile,...
Sparse signal processing using iterative method with adaptive thresholding (IMAT)
, Article 2012 19th International Conference on Telecommunications, ICT 2012, 23 April 2012 through 25 April 2012, Jounieh ; 2012 ; 9781467307475 (ISBN) ; Azghani, M ; Imani, P ; Pakrouh, P ; Heydari, S.J ; Golmohammadi, A ; Kazerouni, A ; Khalili, M. M ; Sharif University of Technology
IEEE
2012
Abstract
Classical sampling theorem states that by using an anti-aliased low-pass filter at the Nyquist rate, one can transmit and retrieve the filtered signal. This approach, which has been used for decades in signal processing, is not good for high quality speech, image and video signals where the actual signals are not low-pass but rather sparse. The traditional sampling theorems do not work for sparse signals. Modern approach, developed by statisticians at Stanford (Donoho and Candes), give some lower bounds for the minimum sampling rate such that a sparse signal can be retrieved with high probability. However, their approach, using a sampling matrix called compressive matrix, has certain...
Non-line-of-sight error mitigation technique for wireless localization in micro-cell networks
, Article 2011 4th IFIP International Conference on New Technologies, Mobility and Security, NTMS 2011 - Proceedings, 7 February 2011 through 10 February 2011, Paris ; 2011 ; 9781424487042 (ISBN) ; Shadi, K ; Golmohammadi, S ; Sharif University of Technology
2011
Abstract
Non Line of Sight (NLOS) propagation is a challenging issue which cause large errors in wireless localization systems. NLOS is especially a dominant source of errors in metropolitan area wireless networks like cellular ones. We discuss our algorithms within cellular network terminology. This paper contributes two novel algorithms. The first algorithm is to extract the NLOS state of base stations and the second one is a correction algorithm to enhance the measurements accuracy. Our introduced algorithms can easily operate with other wireless localization algorithms and reduced NLOS error. These algorithms are proposed for network-based localization because of the amount of calculation
Mechanism understanding of Li-ion separation using a perovskite-based membrane
, Article Membranes ; Volume 12, Issue 11 , 2022 ; 20770375 (ISSN) ; Habibi, M ; Rezvantalab, S ; Mehdizadeh Chellehbari, Y ; Maleki, R ; Razmjou, A ; Sharif University of Technology
MDPI
2022
Abstract
Lithium ions play a crucial role in the energy storage industry. Finding suitable lithium-ion-conductive membranes is one of the important issues of energy storage studies. Hence, a perovskite-based membrane, Lithium Lanthanum Titanate (LLTO), was innovatively implemented in the presence and absence of solvents to precisely understand the mechanism of lithium ion separation. The ion-selective membrane’s mechanism and the perovskite-based membrane’s efficiency were investigated using Molecular Dynamic (MD) simulation. The results specified that the change in the ambient condition, pH, and temperature led to a shift in LLTO pore sizes. Based on the results, pH plays an undeniable role in...
The non-linear effect of oil polarity on the efficiency of low salinity waterflooding: A pore-level investigation
, Article Journal of Molecular Liquids ; January , 2021 ; 01677322 (ISSN) ; Mohammadi, S ; Mahani, H ; Ayatollahi, S ; Sharif University of Technology
Elsevier B. V
2021
Abstract
Oil polarity is an important property impacting the efficiency of low salinity waterflooding (LSWF). It directly affects fluid/fluid and rock/fluid interactions, controlling the interfacial properties and forces. However, the current findings in the literature on the effect of concentration of polar components on oil recovery by LSWF are contradictory. Therefore, the main objective of this paper is to investigate how the type of non-polar fractions and the concentration of acidic polar oil constituents change the trapped oil saturation at the pore-scale during LSWF. In this regard, we conducted a series of microfluidics LSWF experiments in both secondary and tertiary modes, using clay-free...
The non-linear effect of oil polarity on the efficiency of low salinity waterflooding: A pore-level investigation
, Article Journal of Molecular Liquids ; Volume 346 , 2022 ; 01677322 (ISSN) ; Mohammadi, S ; Mahani, H ; Ayatollahi, S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Oil polarity is an important property impacting the efficiency of low salinity waterflooding (LSWF). It directly affects fluid/fluid and rock/fluid interactions, controlling the interfacial properties and forces. However, the current findings in the literature on the effect of concentration of polar components on oil recovery by LSWF are contradictory. Therefore, the main objective of this paper is to investigate how the type of non-polar fractions and the concentration of acidic polar oil constituents change the trapped oil saturation at the pore-scale during LSWF. In this regard, we conducted a series of microfluidics LSWF experiments in both secondary and tertiary modes, using clay-free...
Chlorophyll-based wicking sensing bioplatform coupled with a smartphone-based sample-to-answer analytical device for on-site detection of picric acid
, Article Biosensors and Bioelectronics: X ; Volume 11 , 2022 ; 25901370 (ISSN) ; Abbasi Moayed, S ; Hamzei, Z ; Keshavarz, A ; Yousefi, S ; Hormozi Nezhad, M. R ; Golmohammadi, H ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
The development of inexpensive, equipment-free, portable, and user/environmentally-friendly analytical devices that can be efficiently utilized for on-site detection of PA is still a great challenge. To address these unmet demands, we have developed a smartphone-based disposable sensing bioplatform through immobilization of chlorophyll in a cotton thread for fluorescent monitoring of picric acid (PA). The fluorescence quenching of chlorophyll upon increasing the PA concentration based on the inner filter effect was considered as the sensing strategy in the developed sensor. The fabricated thread-based microfluidic sensing bioplatform was further coupled with a compact, low cost, portable,...
Designing IoT-based Video/Audio Processing Systems
, M.Sc. Thesis Sharif University of Technology ; Gholampour, Iman (Supervisor) ; Haj Sadeghi, Khosrou (Supervisor)
Abstract
The use of IoT-based technologies is expanding in many areas today. The use of audio and video processing in IoT systems has been used as an alternative to human operators by increasing power and reducing processing costs. Due to the large volume of audio and video data and bandwidth limitations, complete data transfer to cloud processing servers is not cost-effective in terms of efficiency and energy consumption. As a result, the solution that has provided good results is to discharge these device tasks to the available clouds. In other words, the capacity of resources in the environment can be used to optimize the total latency of the system and energy consumption. In this dissertation, we...
Nanoparticle-based optical sensor arrays
, Article Nanoscale ; Volume 9, Issue 43 , 2017 , Pages 16546-16563 ; 20403364 (ISSN) ; Ghasemi, F ; Golmohammadi, H ; Abbasi Moayed, S ; Nejad, M. A. F ; Fahimi-Kashani, N ; Jafarinejad, S ; Shahrajabian, M ; Hormozi-Nezhad, M. R ; Sharif University of Technology
2017
Abstract
As in many other methods that have integrated nanoparticles (NPs), the chemical nose/tongue strategy has also progressed greatly since the entrance of NPs into this field. The fascinating tunable physicochemical properties of NPs have made them powerful candidates for array-based sensing platforms and have enabled the development of real-time, sensitive and portable systems that are able to target complex mixtures of analytes. In particular, the unique optical properties of NPs have a key role in providing promising array-based sensing approaches. This review will describe the main aspects and processes of most common NP-based optical sensor arrays. The fundamental steps in the design of a...
Investigation of Low Salinity Waterflooding Predictive Capability and the Development of a Tool for Screening Candidates
, M.Sc. Thesis Sharif University of Technology ; Mahani, Hassan (Supervisor) ; Ayatollahi, Shahab (Supervisor)
Abstract
Among different enhanced oil recovery (EOR) methods, low salinity waterflooding (LSWF) has been attractive to researchers because of its relative simplicity and lower environmental problems compared to other conventional EOR methods. Numerous researchers have attempted to find the main cause of the low salinity effect (LSE). According to previous studies, several experimental techniques have been proposed for predicting LSE and screening potential field candidates. However, there is a lack of a systematic investigation of all (or even some of) the methods to compare and determine their LSE predictive capability. Predictive capability development is essential because it saves costs and time...
Optimum Power Management Strategy for a Hybrid Vehicle Via Artificial Intelligence
, M.Sc. Thesis Sharif University of Technology ; Salarieh, Hassan (Supervisor) ; Khayyat, Amir Ali Akbar (Supervisor)
Abstract
In the recent years, increasing concerns about the environmental issues necessitatecientists and industrial people to introduce clean and zero emissions vehicles to the global market. Relying on this acute demand,Hybrid Electric Vehicles (HEVs) are knownas one potential solution to lessen the negative effects of transportation industry on ecological systems.HEVs combine an Internal Combustion Engine (ICE) with an Electric Motor/Generator (EMG) and an Energy Storage System (ESS) to produce a fuel efficient and low or zero pollutant powertrain. Increasing the number of components in the powertrain requires a sophisticated strategy to control all drive-line components suitably. Surely, the best...
Semantic log based replication model for optimizing heterogeneous DBMS interaction
, Article 2009 1st International Conference on Advances in Databases, Knowledge, and Data Applications, DBKDA 2009, Gosier, 1 March 2009 through 6 March 2009 ; 2009 , Pages 138-142 ; 9780769535500 (ISBN) ; Kharazmi, S ; Bayati, S ; Golmohammadi, S. K ; Abolhassani, H ; IARIA ; Sharif University of Technology
2009
Abstract
The growth of database application usage requires DataBase Management Systems (DBMS) that are accessible, reliable, and dependable. One approach to handle these requirements is replication mechanism. Replication mechanism can be divided into various categories. Some related works consider two categories for replication mechanisms: heterogeneous and homogenous however majority of them classify them in three groups: physical, trigger-based and log based schema. Log-based replication mechanisms are the most widely used category among DBMS vendors. Adapting such approach for heterogeneous systems is a complex task, because of lack of log understanding in the other end. Semantic technologies...
Nanoparticle-based optical sensor arrays
, Article Nanoscale ; v. 9 , 2017 , pages 16546 – 16563 ; 2040-3364 ; Bigdeli, Arafeh ; Ghasemi, Forough ; Golmohammadi, Hamed ; Abbasi-Moayed, Samira ; Farahmand Nejad, M. Amin ; Fahimi-Kashani, Nafiseh ; Jafarinejad, Somayeh ; Shahrajabian, Maryam ; Sharif University of Technology
Royal Society of Chemistry
2017
Abstract
As in many other methods that have integrated nanoparticles (NPs), the chemical nose/tongue strategy has also progressed greatly since the entrance of NPs into this field. The fascinating tunable physicochemical properties of NPs have made them powerful candidates for array-based sensing platforms and have enabled the development of real-time, sensitive and portable systems that are able to target complex mixtures of analytes. In particular, the unique optical properties of NPs have a key role in providing promising array-based sensing approaches. This review will describe the main aspects and processes of most common NP-based optical sensor arrays. The fundamental steps in the design of a...
Developments of Fluorescence Sensor Arrays Using Nanostructured Sensor Elments and Nanocellulose Substrate for Identification and Discrimination of Biomolecules and Environmental pollutants
, Ph.D. Dissertation Sharif University of Technology ; Hormozi-Nezhad, Mohammad Reza (Supervisor) ; Golmohammadi Ghaneh, Hamed (Co-Supervisor)
Abstract
In the first part of this research, a ratiometric fluorescent sensor array has been developed on nanocellulose platform towards chemical discrimination applications. Bacterial nanocellulose (BC) was utilized for the first time as a novel, flexible and transparent substrate in optical sensor arrays for developing portable and high performance sensor array.. To fabricate this platform, the hydrophobic walls on BC nanopaper substrates were successfully created using laser printing technology. In addition, we have used the properties of immobilized ratiometric fluorescence sensor elements (Carbon Dots- Rhodamine B (CDs-RhB) nanohybrids) on nanopaper platform to improve the visual...
Probability of missed detection as a criterion for receiver placement in MIMO PCL
, Article IEEE National Radar Conference - Proceedings, 7 May 2012 through 11 May 2012, Atlanta, GA ; 2012 , Pages 0924-0927 ; 10975659 (ISSN) ; 9781467306584 (ISBN) ; Chitgarha, M. M ; Radmard, M ; Nayebi, M. M ; Sharif University of Technology
IEEE
2012
Abstract
Using multiple antennas at the transmit and receive sides of a passive radar brings both the benefits of MIMO radar and passive radar. However one of the obstacles arisen in such configuration is the receive antennas placement in proper positions so that the radar performance is improved. Here we just consider the case of positioning one receiver among multiple illuminators of opportunity. Indeed it is a start for the solution of optimizing the geometry of the multiple receivers in a passive radar
An efficient method for the ring opening of epoxides with aromatic amines by Sb(III) chloride under microwave irradiation
, Article Journal of Chemical Research ; Issue 4 , 2008 , Pages 220-221 ; 03082342 (ISSN) ; Hashemi, M. M ; Mottaghi, M. M ; Foroughi, M. M ; Sharif University of Technology
2008
Abstract
SbCl3 supported on montmorillonite K-10 is an efficient catalyst for the ring opening of epoxides with aromatic amines under solvent-free conditions and microwave irradiation to give the corresponding b-amino alcohols in high yields with high regioselectivity