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babagholami-mohammadabadi--behnam
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Liver Segmentation in CT Images
, M.Sc. Thesis Sharif University of Technology ; Manzouri, Mohammad Taghi (Supervisor)
Abstract
Image segmentation has a huge amount of applications in machine vision, target detection, medical image processing, etc. In many medical researches such as Organ and Gland Volume Specification, Analysis of Anatomical Structures and Multimodal Image Registration, Organ
Segmentation is the first step of preprocessing.Since detection of diseases out of medical images depends on organ segmentation results,the segmentation process is done by experts which has a lot of disadvantages such as high time computation, high cost, etc. Hence, designing algorithms that can segment images with high accuracy and need minimum user interaction are desirable. So, in this thesis, a new
knowledge based...
Segmentation is the first step of preprocessing.Since detection of diseases out of medical images depends on organ segmentation results,the segmentation process is done by experts which has a lot of disadvantages such as high time computation, high cost, etc. Hence, designing algorithms that can segment images with high accuracy and need minimum user interaction are desirable. So, in this thesis, a new
knowledge based...
Heterogenization of Ionic Complexes of Mo(VI) with Sulfonated Schiff Base Ligands on the Polysiloxane as Support for Catalytic Epoxidation of Olefins
, M.Sc. Thesis Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
In this project a new molybdenum (VI) complex with tetradentate Schiff base ligand which was soluble in water was synthesized and characterized. In the first step of ligand synthesis, the reaction was performed between salicylaldehyde and aniline, and then used concentrated sulfuric acid for sulfonation. In the next step 5- sulfosalicylaldehyde sodium salt was formed by removing of aniline with heating and using sodium carbonate. In the presence of ethylendiamine and bis (acetylacetonato) dioxomolybdenum(VI) the final product, cis-dioxo sodium (N,N-bis (5-sulfonatosalicyldene)1,2-diaminoethane) molybdenum (VI) complex was synthesized. The complex was characterized by (CHN) elemental...
A new model for inverse Hall-Petch relation of nanocrystalline materials
, Article Journal of Materials Engineering and Performance ; Volume 17, Issue 5 , 2008 , Pages 662-666 ; 10599495 (ISSN) ; Dehghani, K ; Sharif University of Technology
2008
Abstract
In the present article, a new model for inverse Hall-Petch relation in nanocrystalline materials has been proposed. It is assumed that lattice distortion along grain boundaries can cause internal stresses and high internal stresses along grain boundaries can promote the grain boundary yielding. The designed model was then verified using the nanocrystalline-copper data. The minimum grain size for inverse Hall-Petch relation is determined to be about 11 nm for Cu. © 2008 ASM International
Inventory Management and Supply Chain Strategy for one Hospital
, M.Sc. Thesis Sharif University of Technology ; Akhavan Niaki, Taghi (Supervisor)
Abstract
One of the most critical problems in medical supply chain is tracking the pharmaceutical throughout the chain. The challenging solution is to use of barcodes which has numerous limits. Radio frequency identification (RFID) tools are the next generation of barcodes that provide more convenient and faster track of supplies. With automatic workplace, the precision of the system is increased and less personnel is needed. In this study, various medical supply chain management procedures were studied for a hospital and the most appropriate procedure was chosen. According to the hospital conditions, RFID over barcode was the procedure of choice. In order to validate this choice, the ARENA software...
Investigation for Increasing the Life of Broaching Tools with Small Cross Section
, M.Sc. Thesis Sharif University of Technology ; Akbari, Javad (Supervisor)
Abstract
In the proccess of making key slots in lock parts, broaching is necessary. The only procedure or at least the best procedure for making the slots is broaching. High speed and precision, surface quality and the ability to create complicated surfaces in one step are the advantages that make broaching suitable for this product. The cost of tool maintainance and replacement is very important to make this process efficient economically, therefore, determining the factors affecting tool life are important for industries. The purpose of this study is to increase the life of narrow broaching tools. In other words, in this study, the purpose is to design and manufacture the tool in such a way that...
Digital video stabilization using radon transform
, Article 2012 International Conference on Digital Image Computing Techniques and Applications, DICTA 2012, 3 December 2012 through 5 December 2012 ; December , 2012 ; 9781467321815 (ISBN) ; Bagheri Khaligh, A ; Hassanpour, R ; Sharif University of Technology
2012
Abstract
Digital video stabilization is a category of techniques used to reduce the impact of unintentional camera motion such as jitter, jiggle, and other unsteady motions. These unintentional shakings degrade visual quality of videos and reduce the performance of subsequent processes such as video compression. Digital video stabilization which is performed by post processing the acquired frames, suffers from inaccuracy of motion estimation which is mostly due to the local motions of internal moving objects included in videos, and long processing time which prohibits them from being used in real time applications. In this paper we propose a fast and accurate transform based motion estimation method...
Examination of a solar desalination system equipped with an air bubble column humidifier, evacuated tube collectors and thermosyphon heat pipes
, Article Desalination ; Volume 397 , 2016 , Pages 30-37 ; 00119164 (ISSN) ; Behshad Shafii, M ; Sharif University of Technology
Elsevier
2016
Abstract
In this paper, the performance of a novel HDH solar desalination system equipped with a combination of heat pipe (HP), evacuated tube collector (ETC) and air bubble column humidifier is experimentally investigated. This novel HDH system uses advantages of ETC-HP as a highly efficient thermal absorption and conductor device, and at the same time employs the advantages of an air bubble column humidifier, i.e. high interface area and effective mixing in order to heat the water and humidify the air, respectively. The effects of various parameters including incoming air flow rate into the humidifier, initial depth of water in the humidifier, and adding fluids such as oil and water in the space...
A bayesian framework for sparse representation-based 3-d human pose estimation
, Article IEEE Signal Processing Letters ; Vol. 21, issue. 3 , 2014 , pp. 297-300 ; ISSN: 10709908 ; Jourabloo, A ; Zarghami, A ; Kasaei, S ; Sharif University of Technology
2014
Abstract
A Bayesian framework for 3-D human pose estimation from monocular images based on sparse representation (SR) is introduced. Our probabilistic approach aims at simultaneously learning two overcomplete dictionaries (one for the visual input space and the other for the pose space) with a shared sparse representation. Existing SR-based pose estimation approaches only offer a point estimation of the dictionary and the sparse codes. Therefore, they might be unreliable when the number of training examples is small. Our Bayesian framework estimates a posterior distribution for the sparse codes and the dictionaries from labeled training data. Hence, it is robust to overfitting on small-size training...
A robust global motion estimation for digital video stabilization
, Article ecture Notes in Computer Science (iLncluding subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 4 December 2012 through 7 December 2012 ; Volume 7691 LNAI , Decembe , 2012 , Pages 132-143 ; 03029743 (ISSN) ; 9783642351006 (ISBN) ; Jourabloo, A ; Manzuri Shalmani, M. T ; Sharif University of Technology
2012
Abstract
This paper proposes a global motion estimation method to remove unintentional camera motions which degrade the visual quality of image sequences. The proposed approach is based on combination of 2D Radon transform, 1D Fourier transform and 1D Scale transform which can accurately estimate scale, rotational and translational distortions of camera motion and is robust to internal moving objects. Our experimental results with real and synthesized videos indicate the effectiveness of our proposed method
MRI-PET image fusion based on NSCT transform using local energy and local variance fusion rules
, Article Journal of Medical Engineering and Technology ; Vol. 38, issue. 4 , 2014 , p. 211-219 ; Fatemizadeh, E ; Behnam, H ; Sharif University of Technology
2014
Abstract
Image fusion means to integrate information from one image to another image. Medical images according to the nature of the images are divided into structural (such as CT and MRI) and functional (such as SPECT, PET). This article fused MRI and PET images and the purpose is adding structural information from MRI to functional information of PET images. The images decomposed with Nonsubsampled Contourlet Transform and then two images were fused with applying fusion rules. The coefficients of the low frequency band are combined by a maximal energy rule and coefficients of the high frequency bands are combined by a maximal variance rule. Finally, visual and quantitative criteria were used to...
A robust dual source level set method for three-dimensional echocardiography image segmentation
, Article Journal of Theoretical and Applied Information Technology ; Volume 95, Issue 21 , 2017 , Pages 5701-5710 ; 19928645 (ISSN) ; Fatemizadeh, E ; Behnam, H ; Sharif University of Technology
2017
Abstract
Echocardiography as a common place device has been widely used for diagnosis. Segmentation of left ventricle just using the standard level set formulation based on the magnitude of intensity cannot restrict the contour evolution completely due to the lack of sharp edges. This paper aims to introduce a robust method for segmentation of three-dimensional echocardiography images based on two boundary maps namely distance map and probabilistic map as stopping criteria of contour evolution which are extracted using two different approaches. The distance map is extracted by applying Free Form Deformation (FFD) method on manually determined landmarks of initial spherical volume to register the...
An optimized probabilistic edge based level set method for left ventricle segmentation in echocardiography images
, Article Biomedical Research (India) ; Volume 28, Issue 8 , 2017 , Pages 3788-3793 ; 0970938X (ISSN) ; Fatemizadeh, E ; Behnam, H ; Sharif University of Technology
Scientific Publishers of India
2017
Abstract
In this paper, an efficient approach for ultrasonic object segmentation with special application for left ventricle segmentation in echocardiography images is proposed. At first, an efficient hybrid trend for ultrasonic image edge detection is suggested. Then, a modified level set approach is introduced based on the extracted edges and the computed probabilistic map as the stopping criteria for the contour evolution. Both synthetic and clinical images are utilized as validation measures with respect to the prior techniques which indicate outperform results quantitatively and qualitatively. Left ventricle segmentation using proposed method illustrates expert-approved performance, providing a...
A review on state-of-the-art applications of data-driven methods in desalination systems
, Article Desalination ; Volume 532 , 2022 ; 00119164 (ISSN) ; Faegh, M ; Khiadani, M ; Sharif University of Technology
Elsevier B.V
2022
Abstract
The substitution of conventional mathematical models with fast and accurate modeling tools can result in the further development of desalination technologies and tackling the need for freshwater. Due to the great capability of data-driven methods in analyzing complex systems, several attempts have been made to study various desalination systems using data-driven approaches. In this state-of-the-art review, the application of various artificial intelligence and design of experiment data-driven methods for analyzing different desalination technologies have been thoroughly investigated. According to the applications of data-driven methods in the field of desalination, the reviewed...
PSSDL: Probabilistic semi-supervised dictionary learning
, Article Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) ; Volume 8190 , Issue PART 3 , 2013 , Pages 192-207 ; 03029743 (ISSN) ; 9783642409936 (ISBN) ; Zarghami, A ; Zolfaghari, M ; Baghshah, M. S ; Sharif University of Technology
2013
Abstract
While recent supervised dictionary learning methods have attained promising results on the classification tasks, their performance depends on the availability of the large labeled datasets. However, in many real world applications, accessing to sufficient labeled data may be expensive and/or time consuming, but its relatively easy to acquire a large amount of unlabeled data. In this paper, we propose a probabilistic framework for discriminative dictionary learning which uses both the labeled and unlabeled data. Experimental results demonstrate that the performance of the proposed method is significantly better than the state of the art dictionary based classification methods
Automatic segmentation of brain MRI in high-dimensional local and non-local feature space based on sparse representation
, Article Magnetic Resonance Imaging ; Volume 31, Issue 5 , 2013 , Pages 733-741 ; 0730725X (ISSN) ; Fatemizadeh, E ; Behnam, H ; Sharif University of Technology
2013
Abstract
Automatic extraction of the varying regions of magnetic resonance images is required as a prior step in a diagnostic intelligent system. The sparsest representation and high-dimensional feature are provided based on learned dictionary. The classification is done by employing the technique that computes the reconstruction error locally and non-locally of each pixel. The acquired results from the real and simulated images are superior to the best MRI segmentation method with regard to the stability advantages. In addition, it is segmented exactly through a formula taken from the distance and sparse factors. Also, it is done automatically taking sparse factor in unsupervised clustering methods...
Adaptive sparse representation for MRI noise removal
, Article Biomedical Engineering - Applications, Basis and Communications ; Volume 24, Issue 5 , October , 2012 , Pages 383-394 ; 10162372 (ISSN) ; Fatemizadeh, E ; Behnam, H ; Sharif University of Technology
World Scientific
2012
Abstract
Sparse representation is a powerful tool for image processing, including noise removal. It is an effective method for Gaussian noise removal by taking advantage of a fixed and learned dictionary. In this study, the variable distribution of Rician noise is reduced in magnetic resonance (MR) images by sparse representation based on reconstruction error sets. Standard deviation of Gaussian noise is used to find these errors locally. The proposed method represents two formulas for local error calculation using standard deviation of noise. The acquired results from the real and simulated images are comparable, and in some cases, better than the best Rician noise removal method due to the...
Thermodynamic analysis of a novel combined power and refrigeration cycle comprising of EKalina and ejector refrigeration cycles
, Article International Journal of Refrigeration ; Volume 104 , 2019 , Pages 291-301 ; 01407007 (ISSN) ; Faegh, M ; Shafii, M. B ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
A novel combined power and refrigeration cycle is introduced and analyzed from the thermodynamic standpoint. The proposed cycle is an integration of a Kalina cycle equipped with an ejector (EKalina) and an ejector refrigeration cycle (ERC). In order to enhance the overall cycle performance, the possibility of employing two-phase ejectors in combined power and refrigeration cycles is studied. A parametric analysis is conducted to investigate the effects of the key thermodynamic parameters namely turbine inlet pressure, split ratio, basic ammonia concentration, heat source and evaporator temperatures on the cycle performance. The developed model is also verified with available data and it is...
Probabilistic non-linear distance metric learning for constrained clustering
, Article MultiClust 2013 - 4th Workshop on Multiple Clusterings, Multi-View Data, and Multi-Source Knowledge-Driven Clustering, in Conj. with the 19th ACM SIGKDD Int. Conf. on KDD 2013 ; 2013 ; 9781450323345 (ISBN) ; Zarghami, A ; Pourhaghighi, H. A ; Manzuri Shalmani, M. T ; Sharif University of Technology
2013
Abstract
Distance metric learning is a powerful approach to deal with the clustering problem with side information. For semi-supervised clustering, usually a set of pairwise similarity and dissimilarity constraints is provided as supervisory information. Although some of the existing methods can use both equivalence (similarity) and inequivalence (dissimilarity) constraints, they are usually limited to learning a global Mahalanobis metric (i.e., finding a linear transformation). Moreover, they find metrics only according to the data points appearing in constraints, and cannot utilize information of other data points. In this paper, we propose a probabilistic metric learning algorithm which uses...
Effect of cooling rate on microstructure and mechanical properties of gray cast iron
, Article Materials Science and Engineering A ; Volume 528, Issue 2 , 2010 , Pages 583-588 ; 09215093 (ISSN) ; Davami, P ; Varahram, N ; Sharif University of Technology
2010
Abstract
This paper presents the results obtained and the deductions made from a series of microstructural studies and mechanical tests involving gray cast iron which was sand cast using a variety of modules. The effect of cooling rate on the primary dendrite arm spacing (DAS), secondary dendrite arm spacing (SDAS), thickness of ferrite-cementite layer (λe) and the hardness (HB) were evaluated. Results show that the both DAS and SDAS and also λe are highly dependent on the cooling rate, and they decreases as the cooling rate increases. More attempts were also done to correlate the HB with DAS, SDAS and λe. It was found that HB increases as DAS, SDAS and λe decreases
Feasibility Study of Offering Generalized Equivalent Model for Drag Polar in Formation Flight
, M.Sc. Thesis Sharif University of Technology ; Malaek, Mohammad Bagher (Supervisor)
Abstract
The increasing demand for air transportation, along with air traffic limitations and environmental pollution concerns, necessitate a comprehensive study in the field of airspace-management. In this regard, one of the promising alternatives is flying smarter via “Formations”. In fact, many works have discussed the benefits of “Commercial Formation Flights”; however, none have discussed a practical way to manage such formations for long-distance cruise. This paper discusses a new approach to manage the “Geometrical Arrangement” of such flights in an efficient manner. In fact, with the help of the so called “Game Theory” and without complex computations we are able to guide each individual...