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    Medical image segmentation for skin lesion detection via topological data analysis

    , Article 16th International Conference on Ubiquitous Information Management and Communication, IMCOM 2022, 3 January 2022 through 5 January 2022 ; 2022 ; 9781665426787 (ISBN) Jazayeri, N ; Jazayeri, F ; Sajedi, H ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2022
    Abstract
    According to the WHO, two individuals die every hour from skin cancer and about 9500 people get skin cancer every day just in the United States. Various computer vision algorithms have been introduced for skin lesion detection, classification, and segmentation. This paper proposes a new segmentation-based algorithm in order to select target components using the persistence diagram of the input images. The results, in comparison with the existing seven different both clustering-and histogram-based segmentation methods using three metrics, show improved performance. Medical image segmentation is an essential task in computer-aided diagnosis. The main improvement of our method is to detect one... 

    Extraction and automatic grouping of joint and individual sources in multi-subject fMRI data using higher order cumulants

    , Article IEEE Journal of Biomedical and Health Informatics ; 24 May , 2018 ; 21682194 (ISSN) Pakravan, M ; Shamsollahi, M. B ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2018
    Abstract
    The joint analysis of multiple datasets to extract their interdependency information has wide applications in biomedical and health informatics. In this paper, we propose an algorithm to extract joint and individual sources of multi-subject datasets by using a deflation based procedure, which is referred to as joint/individual thin independent component analysis (JI-ThICA). The proposed algorithm is based on two cost functions utilizing higher order cumulants to extract joint and individual sources. Joint sources are discriminated by fusing signals of all subjects, whereas individual sources are extracted separately for each subject. Furthermore, JI-ThICA algorithm estimates the number of... 

    Extraction and automatic grouping of joint and individual sources in multisubject fMRI data using higher order cumulants

    , Article IEEE Journal of Biomedical and Health Informatics ; Volume 23, Issue 2 , 2019 , Pages 744-757 ; 21682194 (ISSN) Pakravan, M ; Shamsollahi, M. B ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    Abstract
    The joint analysis of multiple data sets to extract their interdependency information has wide applications in biomedical and health informatics. In this paper, we propose an algorithm to extract joint and individual sources of multisubject data sets by using a deflation-based procedure, which is referred to as joint/individual thin independent component analysis (JI-ThICA). The proposed algorithm is based on two cost functions utilizing higher order cumulants to extract joint and individual sources. Joint sources are discriminated by fusing signals of all subjects, whereas individual sources are extracted separately for each subject. Furthermore, JI-ThICA algorithm estimates the number of... 

    Essays In Iranian Wholesale Electricity Market

    , Ph.D. Dissertation Sharif University of Technology Mardani, Hassan (Author) ; Fatemi Ardestani, Farshad (Supervisor) ; Ghazizadeh, Mohammad Sadegh (Supervisor)
    Abstract
    In this thesis, consider three important questions in the Iranian Wholesale Electricity Market (IWEM) and answer its. The first one is whether the bidding behavior of the firms in the IWEM has been ex-post optimal? The results of the research show that, on average, the firm’s bidding behavior didn’t optimal in the IWEM, and therefore the bidding strategy of them could be improved. This issue is importance from the regulatory viewpoint in terms of assessing market efficiency and market power of firms, as well as from the firm’s point of view to improve the bidding strategy and increase its profits. The second issue is the assessment of the firm’s ability to exercise unilateral market power by... 

    Analyzing Microarray Data Via Learning DNA Cross Hybridization

    , M.Sc. Thesis Sharif University of Technology Hassani Bidgoli, Mansoor (Author) ; Motahari, Abolfazl (Supervisor) ; Rabiee, Hamid Reza (Co-Advisor)
    Abstract
    Gene expression microarrays include thousands of probes spotted on their surface to measure the expression level of a set of genes. Identifying the amount of a transcript level by hybridization, each probe is complementary to a fragment of a specific gene transcripts. Although probes are designed to avoid crosshybridization to non-specific transcripts, occurrences of cross-hybridizations is inevitable due to massive probes that are spotted on microarrays. The main question is whether these non-specific cross-hybridization have significant effect on the downstream analysis of gene expression microarray datasets. This thesis aims at answering to this question by considering datasets from... 

    Development of a Method to Quantitative Assessment of Fatigue in Upper Limb Rehabilitation in Stroke Patients

    , M.Sc. Thesis Sharif University of Technology Zare Mohammadjani, Alireza (Author) ; Behzadipour, Saeed (Supervisor)
    Abstract
    Stroke is a common neurological disorder that can lead to a large number of complications such as mobility impairments. Rehabilitation has been known as the most effective method of treatment. In recent years, many studies have been conducted on investigating the effective factors in increasing the efficiency of the rehabilitation process. One of these parameters is muscle fatigue. The aim of this study is to devise a method for detection and quantification of fatigue level in stroke patients while performing an upper limb rehabilitation exercise in a virtual reality environment. This may be used by the therapist or the VR rehab application to optimally adjust the type and intensity of the... 

    Developing a New Framework for Assessing the Impact of Data Uncertainty on Water Quality Index based on Multivariate Analysis

    , M.Sc. Thesis Sharif University of Technology Jahangiri, Farshad (Author) ; Sheikholeslami, Razi (Supervisor)
    Abstract
    Over the past several decades, human activities have resulted in a significant increase in surface and ground water pollution. Human activities have caused significant pollution of surface and groundwater, with pollutants like nitrates, phosphorus, heavy metals, toxins, and chemical fertilizers degrading water quality. In order to control pollution and reduce the concentration of pollutants in water, it is necessary to use appropriate numerical criteria to evaluate and manage the quality of water resources. The water quality index, as a scoring method for investigating the combined effects of independent parameters on overall water quality, is a widely-used metric for measuring the quality... 

    Local Personalized Differential Privacy in Statistical Databases

    , M.Sc. Thesis Sharif University of Technology Golgolnia, Milad (Author) ; Jalili, Rasool (Supervisor)
    Abstract
    Usually, developers analyze data in order to enhance the services they provide to users, but this data analysis may compromise the privacy of the users during this process. Alternatively, service providers may choose to share their data with a third party for the purpose of data analysis, but they may have a strong aversion to sharing the personal information of their users with them. In response to these concerns and considerations, some countries have enacted legislation in this area. The method of protecting privacy has been proposed in a variety of ways, however most of them lack a precise mathematical and formal definition. In the end, there is no guarantee that this will ensure that... 

    Investigation into the capability of a modern decline curve analysis for gas condensate reservoirs

    , Article Scientia Iranica ; Vol. 18, issue. 3 C , June , 2011 , p. 491-501 ; ISSN: 10263098 Sadeghi Boogar, A ; Gerami, S ; Masihi, M ; Sharif University of Technology
    Abstract
    Techniques of production data analysis for single-phase oil and gas reservoirs have advanced significantly over the past few years. These techniques range from traditional (Arps and Fetkovich) to modern (for the variation of operating conditions at the wellbore). The application of these techniques for analysis of the production data of a gas condensate reservoir may not yield reliable answers due to the fact that the flow of fluid in gas condensate reservoirs is not single-phase. This paper presents the treatment of a modern method of production data analysis (single-phase flow) to analyze the production data of a gas condensate reservoir (two-phase flow). For this purpose, a single-phase... 

    Frequency domain identification of the Nomoto model to facilitate Kalman filter estimation and PID heading control of a patrol vessel

    , Article Ocean Engineering ; Volume 72 , November , 2013 , Pages 344-355 ; 00298018 (ISSN) Banazadeh, A ; Ghorbani, M. T ; Sharif University of Technology
    2013
    Abstract
    This paper presents a detailed frequency-domain system identification method applied to identify steering dynamics of a coastal patrol vessel using a data analysis software called CIFER. Advanced features such as the Chirp-Z transform and composite window optimization are used to extract high quality frequency responses. An accurate, robust and linear transfer function model is derived for yaw and roll dynamics of the vessel. To evaluate the accuracy of the identified model, time domain responses from a 45-45 zig-zag test are compared with the responses predicted by the identified model. The identified model shows excellent predictive capability and is well suited for simulation and... 

    A comprehensive frequency domain identification of a coastal patrol vessel

    , Article ICEE 2012 - 20th Iranian Conference on Electrical Engineering, 15 May 2012 through 17 May 2012 ; May , 2012 , Pages 904-909 ; 9781467311489 (ISBN) Ghorbani, M. T ; Banazadeh, A ; Sharif University of Technology
    2012
    Abstract
    In This paper detailed frequency-domain system identification method is applied to identify steering dynamics of a naval coastal patrol vessel using a data analysis software tool, called CIFER. Advanced features such as Chirp-Z transform and composite windowing techniques are used to extract high quality frequency responses. An accurate, linear and robust transfer function models are derived for yaw and roll dynamics of the vessel. In addition, to evaluate the accuracy of the identified model, time-domain responses from a 45-45 zig-zag test are compared with the responses predicted by the identified model. The model shows excellent predictive capability that is well suited for simulation... 

    Comprehensive two-dimensional gas chromatography (GC×GC) retention time shift correction and modeling using bilinear peak alignment, correlation optimized shifting and multivariate curve resolution

    , Article Chemometrics and Intelligent Laboratory Systems ; Volume 117 , 2012 , Pages 80-91 ; 01697439 (ISSN) Parastar, H ; Jalali Heravi, M ; Tauler, R ; Sharif University of Technology
    Elsevier  2012
    Abstract
    A combination of peak alignment methods and multivariate curve resolution (MCR) is proposed for handling retention time shifts and modeling of comprehensive two-dimensional gas chromatographic (GC × GC) data in the case of univariate detection systems such as in flame ionization detection (FID) or in total ion current mass spectrometry (TIC-MS) detection. A new bilinear peak alignment (BPA) method, based on MCR, is first proposed to correct for progressive within run retention time shifts in GC × GC due to temperature programming effects on second chromatographic dimension. The performance of the proposed peak alignment method is compared to that of the correlation optimized warping (COW)... 

    Investigation into the capability of a modern decline curve analysis for gas condensate reservoirs

    , Article Scientia Iranica ; Volume 18, Issue 3 C , June , 2011 , Pages 491-501 ; 10263098 (ISSN) Sadeghi Boogar, A ; Gerami, S ; Masihi, M ; Sharif University of Technology
    2011
    Abstract
    Techniques of production data analysis for single-phase oil and gas reservoirs have advanced significantly over the past few years. These techniques range from traditional (Arps and Fetkovich) to modern (for the variation of operating conditions at the wellbore). The application of these techniques for analysis of the production data of a gas condensate reservoir may not yield reliable answers due to the fact that the flow of fluid in gas condensate reservoirs is not single-phase. This paper presents the treatment of a modern method of production data analysis (single-phase flow) to analyze the production data of a gas condensate reservoir (two-phase flow). For this purpose, a single-phase... 

    Steganalysis of internet data, a feasibility study

    , Article 2011 International Symposium on Computer Networks and Distributed Systems, CNDS 2011, Tehran, 23 February 2011 through 24 February 2011 ; 2011 , Pages 61-66 ; 9781424491544 (ISBN) Gholampour, I ; Khalilian, H ; Ghaemmaghami, S ; Sharif University of Technology
    2011
    Abstract
    This paper addresses the feasibility of applying realtime steganalysis to the Internet data. To reach a practical solution, we have employed offline procedures to minimize the volume of the data to be processed by an online real-time system. Possible offline services that can be provided to an online system then led us to appropriate network designs for the online system. To go into detail of the online systems, we have carefully analyzed some well-known, state-of-the-art steganalysis algorithms and estimated their processing power and memory requirements. Some formulas are derived to relate the network bit rate with the number of the processing units, their processing power, and memory... 

    Electrocardiographic ST-segment depression and exposure to traffic-related aerosols in elderly subjects with coronary artery disease

    , Article Environmental Health Perspectives ; Volume 119, Issue 2 , Feb , 2011 , Pages 196-202 ; 00916765 (ISSN) Delfino, R. J ; Gillen, D. L ; Tjoa, T ; Staimer, N ; Polidori, A ; Arhami, M ; Sioutas, C ; Longhurst, J ; Sharif University of Technology
    2011
    Abstract
    Background: Air pollutants have not been associated with ambulatory electrocardiographic evidence of ST-segment depression ≥ 1 mm (probable cardiac ischemia). We previously found that markers of primary (combustion-related) organic aerosols and gases were positively associated with circulating biomarkers of inflammation and ambulatory blood pressure in the present cohort panel study of elderly subjects with coronary artery disease. Objectives: We specifically aimed to evaluate whether exposure markers of primary organic aerosols and ultrafine particles were more strongly associated with ST-segment depression of ≥ 1 mm than were secondary organic aerosols or PM 2.5 (particulate matter with... 

    A simple transformation method in skewness reduction

    , Article International Journal of Engineering, Transactions A: Basics ; Volume 24, Issue 2 , June , 2011 , Pages 169-175 ; 17281431 (ISSN) Abbasi, B ; Niaki, S. T. A ; Seyedan, S. E ; Sharif University of Technology
    Materials and Energy Research Center  2011
    Abstract
    Statistical analysis of non-normal data is usually more complicated than that for normal distribution. In this paper, a simple root/power transformation technique developed by Niaki, et al [1] is extended to transform right and left skewed distributions to nearly normal. The value of the root/power is explored such that the skewness of the transformed data becomes almost zero with an acceptable error. The proposed method is then compared to the well-known and complicated Box, et al [2] transformation method for different left and right skewed distributions using Monte Carlo simulation. While the proposed procedure is easy to understand and to implement, the results of the simulation study... 

    MCRC software: A tool for chemometric analysis of two-way chromatographic data

    , Article Chemometrics and Intelligent Laboratory Systems ; Volume 104, Issue 2 , 2010 , Pages 155-171 ; 01697439 (ISSN) Jalali Heravi, M ; Parastar, H ; Kamalzadeh, M ; Tauler, R ; Jaumot, J ; Sharif University of Technology
    2010
    Abstract
    This paper describes the development and implementation of MCRC software, chemometric software for Multivariate Curve Resolution of two-way Chromatographic data. MCRC software is developed for chemometric analysis of chromatographic data; however, it may also be used for other types of multivariate data. It consists of five groups of techniques for preprocessing, chemical rank determination, local rank analysis, multivariate resolution and peak integration. This software has the ability of the analysis of complex multi-component chromatographic signals of gas chromatography-mass spectrometry (GC-MS) and high performance liquid chromatography-diode array detection (HPLC-DAD). The software... 

    Capturing single-cell heterogeneity via data fusion improves image-based profiling

    , Article Nature Communications ; Volume 10, Issue 1 , 2019 ; 20411723 (ISSN) Rohban, M. H ; Abbasi, H. S ; Singh, S ; Carpenter, A. E ; Sharif University of Technology
    Nature Publishing Group  2019
    Abstract
    Single-cell resolution technologies warrant computational methods that capture cell heterogeneity while allowing efficient comparisons of populations. Here, we summarize cell populations by adding features’ dispersion and covariances to population averages, in the context of image-based profiling. We find that data fusion is critical for these metrics to improve results over the prior alternatives, providing at least ~20% better performance in predicting a compound’s mechanism of action (MoA) and a gene’s pathway. © 2019, The Author(s)  

    Investigating time-varying functional connectivity derived from the Jackknife Correlation method for distinguishing between emotions in fMRI data

    , Article Cognitive Neurodynamics ; Volume 14, Issue 4 , 2020 , Pages 457-471 Ghahari, S ; Farahani, N ; Fatemizadeh, E ; Motie Nasrabadi, A ; Sharif University of Technology
    Springer  2020
    Abstract
    Investigating human brain activity during expressing emotional states provides deep insight into complex cognitive functions and neurological correlations inside the brain. To be able to resemble the brain function in the best manner, a complex and natural stimulus should be applied as well, the method used for data analysis should have fewer assumptions, simplifications, and parameter adjustment. In this study, we examined a functional magnetic resonance imaging dataset obtained during an emotional audio-movie stimulus associated with human life. We used Jackknife Correlation (JC) method to derive a representation of time-varying functional connectivity. We applied different binary measures... 

    Online analysis of local field potentials for seizure detection in freely moving rats

    , Article Iranian Journal of Basic Medical Sciences ; Volume 23, Issue 2 , 2020 , Pages 173-177 Zare, M ; Nazari, M ; Shojaei, A ; Raoufy, M. R ; Mirnajafi Zadeh, J ; Sharif University of Technology
    Mashhad University of Medical Sciences  2020
    Abstract
    Objective(s): Seizure detection during online recording of electrophysiological parameters is very important in epileptic patients. In the present study, online analysis of field potential recordings was used for detecting spontaneous seizures in epileptic animals. Materials and Methods: Epilepsy was induced in rats by pilocarpine injection. During the chronic period of the pilocarpine model, local field potential (LFP) recording was run for at least 24 hr. At the same time, video monitoring of the animals was done to determine the real time of seizure occurrence. Both power and sample entropy of LFP were used for online analysis. Results: Obtained results showed that changes in LFP power...