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calibration
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Correction to: Pose estimation of soccer players using multiple uncalibrated cameras (Multimedia Tools and Applications, (2016), 75, 12, (6809-6827), 10.1007/s11042-015-2611-8)
, Article Multimedia Tools and Applications ; Volume 78, Issue 2 , 2019 , Pages 2641- ; 13807501 (ISSN) ; Seyedarabi, H ; Kasaei, S ; Sharif University of Technology
Springer New York LLC
2019
Abstract
In the pdf version of this article, the captured corresponding author was incorrect when it is correctly presented in the online version. The correct corresponding author should be Hadi Seyedarabi. It is corrected in this correction article. © 2018, Springer Science+Business Media, LLC, part of Springer Nature
Obtaining the effect of sewage network on groundwater quality using MT3DMS code: Case study on Bojnourd plain
, Article Groundwater for Sustainable Development ; Volume 11 , October , 2020 ; Rahimi, H ; Kamaliardakani, M ; Salim, R ; Sharif University of Technology
Elsevier B. V
2020
Abstract
Groundwater contamination is a significant problem related strongly to both the protection of the environment and the need for water. In the present study, groundwater quality was investigated in the Bojnourd watershed. The Bojnourd watershed is located in the northeast of Iran, which covers 65.5 km2 of the North Khorasan province area. There are 11 extracting wells in the region. Annual water extraction from the alluvial aquifer in the area is used for agriculture, drinking, sanitary and industrial consumptions. In this research, groundwater quantity modeling, including calibration and verification by GMS software, had been performed. In the quality modeling stage, pollution contours for...
Optimization-based gravity-assisted calibration and axis alignment of 9-degrees of freedom inertial measurement unit without external equipment
, Article Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering ; Volume 234, Issue 2 , 2020 , Pages 192-207 ; Salarieh, H ; Alasty, A ; Sharif University of Technology
SAGE Publications Ltd
2020
Abstract
Applicable in numerous fields, low-cost micro-electromechanical system inertial measurement units often require on-sight calibration by the end user due to the existence of systematic errors. A 9-degrees of freedom inertial measurement unit comprises a tri-axis accelerometer, a tri-axis gyroscope, and a tri-axis magnetometer. Various proposed multi-position calibration methods can calibrate tri-axis accelerometers and magnetometers to a degree. Yet the full calibration of a tri-axis gyroscope and axis alignment of all the sensors still often requires equipment such as a rate table to generate a priori known angular velocities and attitudes or relies on the disturbance-prone magnetometer...
On the dissemination of the discourse of going: The case of Iranian for-profit study abroad institution's chronotopic representation of ideal life there
, Article Language and Communication ; Volume 80 , September , 2021 , Pages 11-24 ; 02715309 (ISSN) ; Rezaei, S ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
This research addresses the escalation of the ‘discourse of going’ among Iranian educated people in recent years through highlighting the influential role played by for-profit study abroad institutions. Utilizing a discourse-analytic approach, we engage the theoretical concept of chronotope, caliberation, and commodification to investigate the ways through which for-profit study abroad institutions represent the images of ‘life beyond’. The data were obtained in interview sessions with ten certified Iranian study-abroad institutions. The results of the data analysis revealed two main themes, namely, hypothetical utopia there and dystopia here as well as success here-and-now and...
A 1-V 400MS/s 14bit self-calibrated CMOS DAC with enhanced dynamic linearity
, Article 2004 IEEE International Symposium on Circuits and Systems - Proceedings, Vancouver, BC, 23 May 2004 through 26 May 2004 ; Volume 1 , 2004 , Pages I349-I352 ; 02714310 (ISSN) ; Mehrmanesh, S ; Atarodi, M ; Aslanzadeh, H. A ; Sharif University of Technology
2004
Abstract
A 1-V CMOS current steering digital to analog converter with enhanced static and dynamic linearity is presented. The 14-bit static linearity is achieved by a novel background analog self calibration technique which is suitable for low voltage applications and does not require error measurement and correction circuits. To improve dynamic linearity at high frequencies, a new low power track/attenuate output stage is used at the DAC output. Integral and differential nonlinearities of the proposed DAC corresponding, to 14-bit specification are less than 0.35LSB and 0.25LSB, respectively. The DAC is functional up to 400MS/S with SFDR better than 71dB in the Nyquist band. The circuit has been...
World city mode choice: Choice of rail public transportation
, Article Scientia Iranica ; Volume 11, Issue 4 , 2004 , Pages 320-331 ; 10263098 (ISSN) ; Tabatabaee, N ; Kermanshah, M ; Aashtiani, H. Z ; Toobaei, S ; Sharif University of Technology
Sharif University of Technology
2004
Abstract
The choice of technology to transport passengers in large metropolitan areas is an important issue everywhere. There are many factors involved in this choice. This paper deals with the possibility of the objective use of available information in the analysis of the suitability of a rail public transport system for a city. A database has been made from publications on public city transportation and country level information. Logit models of choice have been calibrated by the maximum likelihood and nonlinear least square methods based on the acquired information. Each city is treated as an "individual", choosing rail or non-rail modes for its trips. Only cities with a population of more than...
, M.Sc. Thesis Sharif University of Technology ; Sayyadi, Hassan (Supervisor) ; Abbaspour, Madjid (Supervisor)
Abstract
Now a day measuring dimensions plays an important role in industries. Improving the technology of measuring the dimensions, leads to higher quality of production. It is important for industries to have a rapid and accurate dimensions in short time. In this thesis, we worked on measuring dimensions with 3D laser scanner and in the end, the results related to accuracy and speed and efficiency of the system was shown in the thesis
Integrated Navigation for Attitude and Orbit Estimation of Nano satellite with Online Calibration
, M.Sc. Thesis Sharif University of Technology ; Salarieh, Hassan (Supervisor) ; Alasti, Aria (Supervisor) ; Jalili, Hadi (Co-Supervisor)
Abstract
In this study, integrated navigation for attitude and orbit estimation of nanosatellite with online magnetometer calibration is derived. This algorithm has been developed based on the Extended Kalman Filter and Unscented Kalman Filter and the unknown magnetometer’s parameters (such as bias vector and scale factor orthogonal matrix and non-orthognal misallignmet matrix) are estimated in order to calibration of this sensor. In order to determine the location and orientation of the satellite, many different algorithms have been developed which have the ability to determine the location without the need for GPS sensor; it is necessary to be calibrated and ensure proper performance of these...
Development of an Online Calibration Algorithm for Three Axis-Magnetic Sensor through Data Fusion Techniques
, M.Sc. Thesis Sharif University of Technology ; Salarieh, Hassan (Supervisor)
Abstract
There are challenges in controlling and guidance of vehicles which makes it necessary to have true information about the position, velocity, and orientation of the system. This issue is severe to some extent when a UAV is the object to be controlled. The navigation system is responsible for supplying the mentioned information which is usually accompanied with some errors. Therefore, threre are a wide range of algorithms developed for omitting these errors leading to a well-calibrated navigation system. One of the precise and reliable calibration method is based on the data fusion of intertial navigation sensors and magnetometer measurements. As the obtained data via magnetometers are usually...
A second-order advantage achieved with the aid of gold nanoparticle catalytic activity. Determination of nitrophenol isomers in binary mixtures
, Article Analytical Methods ; Vol. 6, issue. 9 , Feb , 2014 , pp. 3056-3064 ; ISSN: 17599660 ; Abdollahi, H ; Hormozi-Nezhad, M. R ; Sharif University of Technology
Abstract
A novel, simple and rapid spectrophotometric method for the determination of nitrophenol (NP) isomer mixtures based on the catalytic activity of gold nanoparticles is described. Gold nanoparticle (∼13 nm) solution was used to catalyze the reduction of NP isomers to aminophenols with an excess amount of NaBH4. The second-order data were obtained by spectrophotometrically monitoring the reduction process of NP isomers. So, multivariate curve resolution optimized by alternative least squares (MCR-ALS) was used to analyze such data. MCR-ALS, an appropriate second-order method, can exploit the so-called 'second order advantage' (the ability to determine in the presence of uncalibrated...
A 4-Bit, 1.6 GS/s low power flash ADC, based on offset calibration and segmentation
, Article IEEE Transactions on Circuits and Systems I: Regular Papers ; Volume 60, Issue 9 , 2013 , Pages 2285-2297 ; 15498328 (ISSN) ; Sharifkhani, M ; Sadughi, S ; Sharif University of Technology
2013
Abstract
A low power 4-bit, 1.6 GS/s flash ADC is presented. A new power reduction technique which masks the unused blocks in a semi-pipeline chain of latches and encoders is introduced. The proposed circuit determines the unused blocks based on a pre-sensing of the signal. Moreover, a reference voltage generator with very low static power dissipation is used. Novel techniques to reduce the sensitivity to dynamic noise are proposed to suppress the noise effects on the reference generator. The proposed circuit reduces the power consumption by 20 percent compared to the conventional structure when a Nyquist rate OFDM signal is applied. The INL and DNL of the converter are smaller than 0.3 LSB after...
Comparative study of partial least squares and multivariate curve resolution for simultaneous spectrophotometric determination of pharmaceuticals in environmental samples
, Article RSC Advances ; Volume 5, Issue 86 , Aug , 2015 , Pages 70017-70024 ; 20462069 (ISSN) ; Shaye, H ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
The potentials of partial least squares regression (PLSR) and multivariate curve resolution alternating least squares (MCR-ALS) are evaluated for the simultaneous determination of diclofenac (DCF), naproxen (NAP), mefenamic acid (MEF) and carbamazepine (CBZ) as target analytes and gemfibrozil (GEM) as an interference in synthetic and real environmental samples. The analysis of first-order UV-Vis spectra is performed using PLSR with different variable selection methods, which include variable importance in projection (VIP), recursive weighted partial least squares (rPLS), regression coefficient (RV) and uninformative variable elimination (UVE), and using MCR-ALS with correlation constraint...
Consistent calibration of magnetometers for nonlinear attitude determination
, Article Measurement: Journal of the International Measurement Confederation ; Volume 73 , 2015 , Pages 180-190 ; 02632241 (ISSN) ; Pourtakdoust, S. H ; Sheikhy, A. A ; Sharif University of Technology
Elsevier
2015
Abstract
Abstract Three-axis magnetometers (TAMs) have been widely utilized as the cornerstone of integrated navigation (IN) and attitude determination (AD) in many aerospace systems. However, accurate navigation and AD demands for precise calibration of TAM. For this purpose, a complete TAM calibration process is presented in the current research to compensate all of the key errors. In this regard, a hyper least square (HyperLS) estimator is extended for accurate and consistent ellipsoid fitting problem of TAM calibration. Subsequently, the calibrated TAM is utilized for real time attitude determination via nonlinear colored noise filters of extended Kalman filter, simplex unscented Kalman filter...
Cuff-less high-accuracy calibration-free blood pressure estimation using pulse transit time
, Article Proceedings - IEEE International Symposium on Circuits and Systems, 24 May 2015 through 27 May 2015 ; Volume 2015-July , 2015 , Pages 1006-1009 ; 02714310 (ISSN) ; 9781479983919 (ISBN) ; Kiani, M.M ; Mohammadzade, H ; Shabany, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
Recently a few methods have been proposed in the literature for non-invasive cuff-less estimation of systolic and diastolic blood pressures. One of the most prominent methods is to use the Pulse Transit Time (PTT). Although it is proven that PTT has a strong correlation with the systolic and diastolic blood pressures, this relation is highly dependent to each individuals physiological properties. Therefore, it requires per person calibration for accurate and reliable blood pressure estimation from PTT, which is a big drawback. To alleviate this issue, in this paper, a novel method is proposed for accurate and reliable estimation of blood pressure that is calibration-free. This goal is...
Application of the WEPP model to determine sources of run-off and sediment in a forested watershed
, Article Hydrological Processes ; Volume 29, Issue 4 , 2015 , Pages 481-497 ; 08856087 (ISSN) ; Meghdadi, A. R ; Sima, S ; Sharif University of Technology
John Wiley and Sons Ltd
2015
Abstract
This study investigates critical run-off and sediment production sources in a forested Kasilian watershed located in northern Iran. The Water Erosion Prediction Project (WEPP) watershed model was set up to simulate the run-off and sediment yields. WEPP was calibrated and validated against measured rainfall-run-off-sediment data. Results showed that simulated run-off and sediment yields of the watershed were in agreement with the measured data for the calibration and validation periods. While low and medium values of run-off and sediment yields were adequately simulated by the WEPP model, high run-off and sediment yield values were underestimated. Performance of the model was evaluated as...
Projection matrix by orthogonal vanishing points
, Article Multimedia Tools and Applications ; 2016 , Pages 1-35 ; 13807501 (ISSN) ; Fouladi, S ; Kasaei, Sh ; Sharif University of Technology
Springer New York LLC
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...
Design and fabrication of an in situ gamma radioactivity measurement system for marine environment and its calibration with Monte Carlo method
, Article Applied Radiation and Isotopes ; Volume 114 , 2016 , Pages 87-91 ; 09698043 (ISSN) ; Vosoughi, N ; Zare, M. R ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
Simulation, design and fabrication of a sealing enclosure is carried out for a NaI(Tl) 2″×2″ detector, to be used as in situ gamma radioactivity measurement system in marine environment. Effect of sealing enclosure on performance of the system in laboratory and marine environment (distinct tank with 10 m3 volume) were studied using point sources. The marine volumetric efficiency for radiation with 1461 keV energy (from 40K) is measured with KCl volumetric liquid source diluted in distinct tank. The experimental and simulated efficiency values agreed well. Marine volumetric efficiency calibration curve is calculated for 60 keV to 1461 keV energy with Monte Carlo method. This curve indicates...
Fabrication, characterization, and error mitigation of non-flat sun sensor
, Article Sensors and Actuators, A: Physical ; Volume 261 , 2017 , Pages 243-251 ; 09244247 (ISSN) ; Durali, M ; Rashidian, B ; Jalali, M. A ; Sharif University of Technology
Abstract
We report the design, fabrication and error analysis of a sun sensor array composed of six photodiodes. The sensor estimates the direction of the sun using a linear least squares method. The performance of the sensor is deteriorated by three major sources: fabrication errors, scattered environmental light, and inexact modeling of photodiodes. Using a calibration procedure and modeling the uniform component of the environmental light, we mitigate the first two errors and significantly reduce root mean squared error from 2.63° to 0.83°. For a Field of View (FOV) of 110°, the maximum estimation error also drops from 3.8° to 1.6°. Through exact mathematical modeling of photodiodes, we...
The Control of an exoskeleton and the reduction of interaction force using human intent detection by EMG signals and torque estimation
, Article Proceedings of the 6th RSI International Conference on Robotics and Mechatronics, IcRoM 2018, 23 October 2018 through 25 October 2018 ; 2019 , Pages 536-541 ; 9781728101279 (ISBN) ; Vossoughi, G. R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
Disability and motor disorders are some of the problems that people may face due to some factors such as accident, spinal cord injuries, brain damage, and the presence of a problem in neurological commands due to stroke. One of the proposed methods for solving the problems of these people is the use of exoskeletons to generate movement. The main goal of this paper is the control of Sharif Exoskeleton Robot and the reduction of interaction force between user and robot by using human intent detection. This goal is done by estimating the knee torque of one degree of freedom in a swing phase using Hill model based on the EMG data from the thigh muscles. Accordingly, the calibration algorithm is...
Uncalibrated multi-view multiple humans association and 3D pose estimation by adversarial learning
, Article Multimedia Tools and Applications ; 2020 ; Kasaei, S ; Sanaei, E ; Sharif University of Technology
Springer
2020
Abstract
Multiple human 3D pose estimation is a useful but challenging task in computer vison applications. The ambiguities in estimation of 2D and 3D poses of multiple persons can be verified by using multi-view frames, in which the occluded or self-occluded body parts of some persons might be visible in other camera views. But, when cameras are moving and uncalibrated, estimating the association of multiple human body parts among different camera views is a challenging task. This paper presents novel methods for multiple human 3D pose estimation and pose association in multi-view camera frames in an uncalibrated camera setup using an adversarial learning framework. The generator is a 3D pose...