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calibration
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Toward calibration of low-precision MEMS IMU using a nonlinear model and TUKF
, Article IEEE Sensors Journal ; Volume 20, Issue 8 , 2020 , Pages 4131-4138 ; Hashemi, M ; Salarieh, H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
MEMS-IMUs have an extensive application in multifarious studies, as well as industrial and commercial areas. It is crucial to diminish their intrinsic errors in a suitable calibration procedure. In this paper, a novel calibration procedure was proposed for Inertial Measurement Units (IMUs) on a turntable. A general nonlinear model of the IMU output including the effects of bias, scale factor, misalignment, and lever arm was derived. Transformed Unscented Kalman Filter (TUKF) was utilized to perform the estimation of error parameters for gyroscopes and accelerometers. The calibration maneuvers were applied using a tri-axis turntable to create input signals. In addition, assuming the sensors...
Evaluation the nonlinear response function of a HPGe detector for 59 keV to 10.7 MeV gamma-rays using a Monte Carlo simulation and comparison with experimental data
, Article Journal of Instrumentation ; Volume 16, Issue 7 , 2021 ; 17480221 (ISSN) ; Riazi, Z ; Jokar, A ; Shahabinejad, H ; Vosoughi, N ; Ghasemi, S. A ; Sharif University of Technology
IOP Publishing Ltd
2021
Abstract
Modeling of High Purity Germanium (HPGe) detector on a wide energy range is important in gamma-ray spectroscopy. The precisely modeled detector can be used for proton-induced prompt gamma-ray spectroscopy. In this work, we used both the gamma-rays of calibration sources and prompt gamma-rays emitted in proton capture reactions to model a coaxial p-type HPGe detector using Geant4 Monte Carlo simulation for the gamma-ray energy range of 59–10764 keV. The calibration sources were 137Cs, 241Am, 60Co, 152Eu, and 133Ba, while the prompt gamma-rays were due to the gamma-ray cascades following the 27Al(p,γ)28Si reaction capture at the resonant energies of 992, 1317 and 2483 keV, as well as the...
Multiplex detection of antidepressants with a single component condition-based colorimetric sensor array
, Article Sensors and Actuators B: Chemical ; Volume 363 , 2022 ; 09254005 (ISSN) ; Bigdeli, A ; Jafarinejad, S ; Hormozi Nezhad, M. R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Pattern-based sensing with multi-component sensor arrays, despite its merits, may be laborious and time-consuming. As an alternative approach, herein, a condition-based single component sensor array has been provided which represents an elegantly simple, low cost and minimally instrumented format for the quantification and classification of antidepressants (ADs). Tuning the pH and ionic strength enabled the single component probe to interact with the target analytes through different binding modes, providing the required cross-reactivity for multiplex detection. The analytical figures of merit verified that the condition-based sensor array is precise and accurate in both the discrimination...
Create an Algorithm for Designing of Button-BPM and Striplines in a Synchrotron
, M.Sc. Thesis Sharif University of Technology ; Samadfam, Mohammad (Supervisor) ; Mohammadzadeh, Mohammad (Co-Advisor)
Abstract
Beam diagnostics is an essential constituent of any accelerator. The position information of the electron beam is obtained by a set of Beam Position Monitors (BPMs), which in addition to determining the position, are used to derive information concerning lattice functions and beam dynamics. To design of Button Beam Position Monitor(BPM) for a Synchrotron Light Source, to get beam stabilities on submicron levels, preliminary studies were done to have optimal design. We present an algorithem which caculate all required parameteres for different design of button BPMs. To calculate induced charge and voltage on each button, Poisson's equation has been solved by Green method. For sensivity...
Integrated Orbit and Attitude Parameter Determination of a Satellite Using Hybrid Nonlinear Filters
, Ph.D. Dissertation Sharif University of Technology ; Pourtakdoust, Hossein (Supervisor)
Abstract
Rapid growth of space traffic and small satellite systems for current and future space missions have generated new enhanced performance requirements for navigation subsystem. As such, the navigation subsystem is considered as a vital part of all active satellite systems that effectively influences their successful missions. In this regard, the present work is dedicated on the subject of autonomous satellite navigation utilizing nonlinear filters, for which some laboratory experimentations have also been implemented. Generally, advanced orbit and attitude estimation algorithms can effectively compensate for the effect of low cost hardware and sensor packs utilized in microsatellites. In...
Agricultural Economics model of Urmia Lake Basin
, M.Sc. Thesis Sharif University of Technology ; Vesal, Mohammad (Supervisor) ; Fatemi Ardestani, Farshad (Supervisor)
Abstract
This Thesis was an effort to write and quantify an agricultural economic model for Urmia Lake Basin and evaluate the change in water consumption in reaction to a policy change. Aggregated form of the data gathered from 33 counties located in Urmia Lake Basin was used in this research. This data includes the quantity used of each input and their costs, in addition to crop yield and their selling price. In our model, the representative farmer takes into account the price of various inputs, crops and the condition of the farm and its limitations and decides on the profit-maximizing crop pattern. In this model, water is one of the most important inputs and its price and availability, effects the...
Estimation of the logit model for the online contraflow problem
, Article Transport ; Volume 25, Issue 4 , 2010 , Pages 433-441 ; 16484142 (ISSN) ; Edrissi, A ; Alibabai, H ; Sharif University of Technology
Abstract
Contraflow or lane reversal is an efficient way for increasing the outbound capacity of a network by reversing the direction of in-bound roads during evacuations. Hence, it can be considered as a potential remedy for solving congestion problems during evacuation in the context of homeland security, natural disasters and urban evacuations, especially in response to an expected disaster. Most of the contraflow studies are performed offline, thus strategies are generated beforehand for future implementation. Online contraflow models, however, would be often computationally demanding and time-consuming. This study contributes to the state of the art of contraflow modelling in two regards. First,...
Robust respiratory flow estimation using statistical properties of tracheal sounds
, Article 2005 27th Annual International Conference of the Engineering in Medicine and Biology Society, IEEE-EMBS 2005, Shanghai, 1 September 2005 through 4 September 2005 ; Volume 7 VOLS , 2005 , Pages 1106-1109 ; 05891019 (ISSN); 0780387406 (ISBN); 9780780387409 (ISBN) ; Moussavi, Z ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2005
Abstract
For any respiratory sound analysis or assessment, respiratory flow must also be measured simultaneously with the sounds. However, due to difficulties and/or inaccuracy of the most flow measurement techniques, several researchers have attempted to estimate flow from respiratory sounds. However, all of the proposed methods heavily depend on the availability of different rates of flow for calibration of the model, which makes their use limited by a large degree. In this paper, a robust and novel method for estimating flow using entropy of the band pass filtered tracheal sounds is proposed. The proposed method is independent of the flow rate chosen for calibration; it requires only one breath...
Sensitivity of a real-time freeway crash prediction model to calibration optimality
, Article European Transport Research Review ; Volume 4, Issue 3 , September , 2012 , Pages 167-174 ; 18670717 (ISSN) ; Hellinga, B ; Sharif University of Technology
2012
Abstract
Background: Real-time crash prediction models are often structured as general log-linear categorical models which must be calibrated using an extensive database. However, there is no method to optimally select the number of categories and the values that define the boundaries between categories when representing continuous measures as categorical variables within the log-linear model. This raises the question of how important the calibration is to the safety impacts estimated when using the crash prediction model. In this paper, we examined the impact that the process used to calibrate the crash prediction model has on estimates of safety impacts of a variable speed limit system. Methods:...
Novel printed body worn sensor for measuring the human movement orientation
, Article Sensor Review ; Volume 36, Issue 3 , 2016 , Pages 321-331 ; 02602288 (ISSN) ; Taghinedjad, S ; Mottaghitalab, V ; Narimani, R ; Parnianpour, M ; Sharif University of Technology
Emerald Group Publishing Ltd
2016
Abstract
Purpose - the purpose of this study is the measuring of the human movement using printed wearable sensor. Human movement measurement is one of the usages for wearable sensors. This technology assists the researchers to collect data from the daily activities of individuals. In other words, the kinematics data of human motion will be extracted from this data and implemented in biomechanical aspects. Design/methodology/approach - This study presents an innovative printed wearable sensor which can be used for measuring human movement orientations. In this paper, the manufacturing process, implementation, measurement setup and calibration procedure of this new sensor will be explained, and the...
Projection matrix by orthogonal vanishing points
, Article Multimedia Tools and Applications ; Volume 76, Issue 15 , 2017 , Pages 16189-16223 ; 13807501 (ISSN) ; Fouladi, S ; Kasaei, S ; Sharif University of Technology
Springer New York LLC
2017
Abstract
Calculation of camera projection matrix, also called camera calibration, is an essential task in many computer vision and 3D data processing applications. Calculation of projection matrix using vanishing points and vanishing lines is well suited in the literature; where the intersection of parallel lines (in 3D Euclidean space) when projected on the camera image plane (by a perspective transformation) is called vanishing point and the intersection of two vanishing points (in the image plane) is called vanishing line. The aim of this paper is to propose a new formulation for easily computing the projection matrix based on three orthogonal vanishing points. It can also be used to calculate the...
A low-power smart temperature sensor for passive UHF RFID tags and sensor nets
, Article 2016 8th International Symposium on Telecommunications, IST 2016, 27 September 2016 through 29 September 2016 ; 2017 , Pages 12-17 ; 9781509034345 (ISBN) ; Kamarei, M ; Fotowat Ahmady, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
A low-power wide-range CMOS temperature sensor architecture is proposed for RFID and Sensor Networks based on temperature-to-frequency conversion using supply voltage controlled sub-threshold ring oscillator. The principles of operation are investigated and proved via simulation results. Most errors are canceled out by this ratio-metric design. An inaccuracy of -0.84°C to +0.34°C occurs over a range of -40°C to 80°C after using a novel in-field digital two-point calibration. The entire sensor consumes less than 93nW to 305nW over the temperature range and can be digitally reconfigured for setting sample rate and resolution in a tradeoff. © 2016 IEEE
Calibration of parallel kinematic machine tools using mobility constraint on the tool center point
, Article International Journal of Advanced Manufacturing Technology ; Volume 45, Issue 5-6 , 2009 , Pages 531-539 ; 02683768 (ISSN) ; Pendar, H ; Alasty, A ; Vossoughi, G. R ; Sharif University of Technology
2009
Abstract
In the application of parallel kinematic machine tools (PKM), because of errors in the geometric parameters, it is necessary to calibrate the PKM to improve the positioning accuracy. In existing self-calibration methods, either some redundant sensors on passive joints or some mobility constraints on the kinematic chains are used. However, the mobility constraints imposed on kinematic chains might apply large forces during the test on legs and passive joints. Also, these kinds of calibrating are applicable only on PKMs in which their actuated joints can be used as passive joints. To overcome weaknesses of existing methods, a novel approach to calibration based on imposing position constraints...
Discrete element model (DEM) simulations of cone penetration test (CPT) measurements and soil classification
, Article Canadian Geotechnical Journal ; Volume 57, Issue 9 , November , 2020 , Pages 1369-1387 ; Martinez, A ; Dejong, J. T ; Sharif University of Technology
Canadian Science Publishing
2020
Abstract
This paper presents a study on the simulation of cone penetration tests (CPTs) using the discrete element model (DEM) method. This study’s main objective is to investigate the effect of different modeling parameters and simulation configurations on the ability of three-dimensional DEM simulations to replicate realistic CPT tip resistance (qc) and friction sleeve shear stress (fs) measurements. The CPT tests were simulated in virtual calibration chambers (VCCs) containing particles calibrated to model the behavior of sand. The parameters investigated included the granular assembly properties, interparticle contact parameters, particle–probe interface characteristics, and simulation...
Evaluation of FT-IR spectroscopy combined with SIMCA and PLS‑DA for detection of adulterants in pistachio butter
, Article Infrared Physics and Technology ; Volume 127 , 2022 ; 13504495 (ISSN) ; Bagheri Garmarudi, A ; Parastar, H ; Toth, G ; Sharif University of Technology
Elsevier B.V
2022
Abstract
This work scrutinized the adulteration of pistachio butter with three potential edible oils using Fourier transform infrared spectroscopy (FT-IR) and multivariate classification methods. Each of the classes, including non-adulterated samples and adulterated samples consisting of pistachio butter mixed with various concentrations of peanut oil, corn oil and sunflower oil, were classified. For this purpose, multivariate methods, including soft independent modeling of class analogy (SIMCA) and partial least squares discriminant analysis (PLS-DA), were applied to classify the FTIR data. After evaluating the model on unknown samples, the results indicated that PLS-DA was better than the SIMCA...
Experimental and Theoretical Investigations of Calibration Methods and Factors Influencing the Forming Limit Diagrams
, M.Sc. Thesis Sharif University of Technology ; Assempour, Ahmad (Supervisor)
Abstract
In designing of sheet metal forming processes, knowledge of the maximum permissible strains in the sheet is of prime importance for the design engineer. Thus, a large amount of experimental and theoretical researches have been carried out to estimate these limiting strains. A renowned and prevalent theoretical method for prediction of forming limits is the Marciniak and Kuczynski model. In this model, it is assumed that a small groove exists in the sheet even before applying the loads; and due to the weakness of this region, necking starts from there. The major problem of the M-K model is requiring of an experimental point to “calibrate” the results. Furthermore, while experiments indicate...
Seismic Behavior Modeling of An Arched-Roof Adobe Building
, M.Sc. Thesis Sharif University of Technology ; Bakhshi, Ali (Supervisor) ; Ghannad, Mohammad Ali (Supervisor)
Abstract
Statistical studies indicate the fact that in Iran, like many other developing countries, a considerable percentage of houses are in the form of traditional buildings, and major losses due to recent earthquakes are because of masonry building collapse. In the early twentieth century in Iran every ten years a destructive earthquake has been occurred which has resulted in huge human casualties and economic losses. After the Bam 2003 earthquake, a team project was defined to investigate the behavior of rural houses with the aim of providing solutions to lessen seismic hazards, and the current study is the fifth phase of the following line of investigations. Among the existing kinds of rural...
ECU Strategies in Management and Control of Catalyst and Oxygen Sensors Before Activation of Lambda Control
, M.Sc. Thesis Sharif University of Technology ; Mozafari, Ali Asghar (Supervisor) ; Saidi, Mohammad Hasan (Supervisor)
Abstract
Recent stringent HC and CO emission regulations are because of increasing consciousness of the perilous influences of exhaust emissions. The chief attempt to pass the standards is to decrease the emissions during cold-start, due to catalytic converters are not efficient until they arrive a light-off temperature. It has been discovered that 50% to 80% of the controlled HC and CO emissions are sent out from tailpipe of automotive during the cold-start. Therefore, in order to minimize the cold-start emissions and fast light-off of catalytic converters, it is important to understand the catalytic converter characteristics and techniques for rapid warm-up catalyst. This thesis describes a...
Numerical Analysis of Adobe Structure with Dome Roof under Earthquake Excitation
, M.Sc. Thesis Sharif University of Technology ; Ghannad , Mohammad Ali (Supervisor) ; Bakhshi, Ali (Co-Advisor)
Abstract
After the heart-rending earthquake in Bam and its severe losses, the engineering community forced to pay special attention to the seismic vulnerability of traditional structures. Therefore, with the aim of reducing of such devastations to minimum, a multi-phase research project was defined at Sharif University of Technology to study the vulnerability and retrofitting of these structures which the current study is the eighth phase of that series research. In the third and fourth phases of this project, a typical adobe building with dome roof was chosen for study making use of shaking table facilities. The tests included both un-retrofitted and retrofitted states and considerable seismic...
Effects of Bending on Forming Limit Diagram (FLD)Based on Marciniak & Kuczynski Method
, M.Sc. Thesis Sharif University of Technology ; Asempour, Ahmad (Supervisor)
Abstract
In designing sheet forming processes, finding out the value of the maximum strain before necking in sheets is extremely important. Therefore, many experimental and theoretical efforts have been carried out in order to answer this question. One of the most well-known and useful theoretical methods in this regard is the Marciniak - Kuczynski method which was introduced in 1967 and is still the topic of many researches. In this model, it is assumed that a groove as a defect primarily exists in the sheet and due to the weakness of this region, necking will initiate. Furthermore, the effects of various parameters such as sensitivity to strain rate, strain path, thickness, three dimensional...