Paulina Mitrea | Technical University of Cluj-Napoca (original) (raw)
Papers by Paulina Mitrea
The main results of this paper establish the superdense unbounded divergence of some discrete bes... more The main results of this paper establish the superdense unbounded divergence of some discrete best approximation operators. 2000 Mathematics Subject Classification: 41A10.
2010 IEEE International Conference on Automation, Quality and Testing, Robotics (AQTR), 2010
This paper is devoted to investigate numerical optimization algorithms of the theory of deformabl... more This paper is devoted to investigate numerical optimization algorithms of the theory of deformable surfaces and to emphasize some of their computerized applications in medical image analysis and prosthetic surgery. After defining the 3D variational deformable model, both in static and dynamic form, an algorithm for finding the optimal deformable surface is presented, together with estimations for its approximation error and a condition for its convergence. Finally, a statistical modeling and a corresponding algorithm applied in surgery are presented.
2006 IEEE International Conference on Automation, Quality and Testing, Robotics, 2006
... Paulina Mitrea*, Alexandru Imbroane** , Alexandru Ioan Mitrea*, Mira Cristiana Anisiu *Techni... more ... Paulina Mitrea*, Alexandru Imbroane** , Alexandru Ioan Mitrea*, Mira Cristiana Anisiu *Technical University Cluj-Napoca, ** Babes-Bolyai University Cluj ... Continuous-Time and Discrete-Time Transformations , Mediamira, Cluj-Napoca, 2005 [3] O. Agratini, I. Chiorean, Gh. ...
2008 IEEE International Conference on Automation, Quality and Testing, Robotics, 2008
This paper is devoted to the mathematical approaches and software implementations in the domain o... more This paper is devoted to the mathematical approaches and software implementations in the domain of deformable models. Based on a general result of calculus of variations, we deduce the Euler-Lagrange-Poisson (ELP) Equation associated to the 2D deformable models, with relevant applications in medical imaging; the optimal solution of these models is found among the solutions (named extremals) of ELP Equation.
2014 IEEE International Conference on Automation, Quality and Testing, Robotics, 2014
ABSTRACT The basic goals of this paper target on the development and implementation of algorithms... more ABSTRACT The basic goals of this paper target on the development and implementation of algorithms which provide the energy-minimizing snakes in parametric form, then in applying them to textural analysis based medical diagnosis. In order to derive these algorithms, we focus on Finite Differences Methods (Explicit and Crank-Nicolson Finite Difference Schemes), widely used in medical image processing applications. We examine the consistency, stability, and convergence rate, proving their increased quality able to provide maximum accuracy when determining the diseased anatomic tissue delimitation in the context of medical images.
Computational and Mathematical Methods in Medicine, 2012
After a brief survey on the parametric deformable models, we develop an iterative method based on... more After a brief survey on the parametric deformable models, we develop an iterative method based on the finite difference schemes in order to obtain energy-minimizing snakes. We estimate the approximation error, the residue, and the truncature error related to the corresponding algorithm, then we discuss its convergence, consistency, and stability. Some aspects regarding the prosthetic sugical methods that implement the above numerical methods are also pointed out.
Applied Medical Informatics, 2019
Viaţa medicală; revistă de informare profesională şi ştiinţifică a cadrelor medii sanitare, 1976
Heart, Lung and Circulation, 2009
Proceeding of 10th …, 2011
1 Introduction The inflammatory bowel diseases (IBD) are a group of disorders that frequently mar... more 1 Introduction The inflammatory bowel diseases (IBD) are a group of disorders that frequently mark the population of the developed countries. Their evolution is frequently chronic, with activation peaks and remission periods, elements that are conditioned by the rapidity of the ...
Springer eBooks, 2010
The main objective of the article is to highlight the role that Web2.0 currently has and could ha... more The main objective of the article is to highlight the role that Web2.0 currently has and could have in the future in supporting the teaching of ICT Design for All. According to this, first the concepts of Web2.0 and eLearning2.0 are clarified and connected. The new way of thinking about eLearning being inspired by the emergence of Web2.0, the term eLearning2.0 was introduced to identify a new paradigm. So, eLearning 2.0, by contrast to eLearning1.0 is built around collaboration, also eLearning2.0 assumes that knowledge is socially constructed. Related to the role of Web2.0 in supporting the teaching of ICT Design for All, the 4 steps involved by the ICT Design For All Teaching Principles are presented and detailed. Finally, some real world examples are shown, as evidence of how the new methods of communication offered by Web2.0 can be used to support students as they learn about Design for All.
International Conference on Electronics, Hardware, Wireless and Optical Communications, Feb 20, 2011
The inflammatory bowel diseases (IBD) are severe, chronic and recurring disorders, requiring cont... more The inflammatory bowel diseases (IBD) are severe, chronic and recurring disorders, requiring continuous patient monitoring. We aim to develop computerized methods for the noninvasive assessment of the bowel inflammation based on ultrasound images. In this work, we study the role of the textural parameters in characterizing different types of inflammatory bowel diseases and the colorectal tumors. Also, the time intensity curves (TIC) are post processed through mathematical modeling, in order to emphasize the behavior of the contrast agent for the considered affections. The relevant textural and TIC parameters are determined through specific methods, and then they are assessed individually and in combination for performing automatic diagnosis. B-mode and contrast-enhanced ultrasound images (CEUS) of biopsied patients are used. The information obtained from the endoscopic images is taken into consideration, as well. The patients were suffering from the following diseases: Crohn's disease, ulcerative recto-colitis, colon cancer. .
HCC (Hepatocellular carcinoma) is the liver cancer form that is the most often met. The actual st... more HCC (Hepatocellular carcinoma) is the liver cancer form that is the most often met. The actual standard for a highly accurate diagnosis of HCC is the biopsy, this being, however, invasive, as well as dangerous. We develop computerized methods, based on advanced image processing, in order to perform automatic, respectively computer aided diagnosis of HCC based on ultrasound images. In this research paper, we analyze the role of several advanced texture analysis specific methods, combined with powerful conventional classifiers, respectively deep learning techniques, for HCC automatic recognition. Regarding the deep learning methods, we focus on Stacked Denoising Autoencoders (SAE), so we study its impact upon the performance of HCC computerized diagnosis. In our experiments, we compare the HCC tumor with both the cirrhotic liver parenchyma on which it evolved and with the hemangioma tumor, the obtained accuracy being around 85%. The actual results are compared, as well, with the previously obtained results in the literature.
Proceedings of 2012 IEEE International Conference on Automation, Quality and Testing, Robotics, 2012
In this paper, we describe briefly the 2D parametric deformable models, then we infer an algorith... more In this paper, we describe briefly the 2D parametric deformable models, then we infer an algorithm, via Crank-Nicolson finite difference scheme for finding the so-called energy-minimizing (i.e. optimal) snake. The residue, the truncature - error and the order of accuracy related to this algorithm are estimated, in order to establish its consistency. We prove that the algorithm leads to better
IFMBE Proceedings, 2009
ABSTRACT This paper is devoted to point out some mathematical methods and techniques in the theor... more ABSTRACT This paper is devoted to point out some mathematical methods and techniques in the theory of deformable models, with applications in medical image analysis. After presenting the definition of 3D-deformable model, some reconstruction methods based on projection operators and discretization methods related to the corresponding evolution equation, are pointed out. Finally, some applications in echographic images are given. KeywordsDeformable variational model-reconstruction methods-projection operators-discretization methods-echographic images
Lecture Notes in Computer Science, 2010
1 Department of Histology, University of Medicine and Pharmacy Iuliu Hatieganu, Cluj-Napoca, Ro... more 1 Department of Histology, University of Medicine and Pharmacy Iuliu Hatieganu, Cluj-Napoca, Romania mcrisan7@yahoo.com, diana_crisan2002@yahoo.com 2 Department of Pharmaceutical Sciences, University of Salerno, Italy ccattani@unisa.it 3 Department of Ultrasonography, ...
2017 10th International Congress on Image and Signal Processing, BioMedical Engineering and Informatics (CISP-BMEI), 2017
Cirrhosis is an important disease, as it can precede liver cancer, and also can lead to death by ... more Cirrhosis is an important disease, as it can precede liver cancer, and also can lead to death by itself. Detecting the severity grades of cirrhosis is a major issue in this context. The best nowadays standard for this purpose is the biopsy, however this procedure is invasive, dangerous for the patient. Also, there is no objective study in order to establish which the cirrhosis grades are. Our research purpose is to discover the cirrhosis grades using computerized methods and to perform non-invasive, computer assisted and automatic diagnosis of the disease evolution phases. Concerning the employed features, we adopted the texture-based methods, able to emphasize those characteristics of the tissue that cannot be detected by the eye of the medical expert. In this paper, we emphasized the role of the CETMCM Matrix concerning the detection of the cirrhosis severity grades. The method was validated by supervised classification, providing a recognition rate above 95%.
6th International Conference on Advancements of Medicine and Health Care through Technology; 17–20 October 2018, Cluj-Napoca, Romania, 2019
Hepatocellular carcinoma (HCC) represents the most frequent form of liver cancer. It evolves from... more Hepatocellular carcinoma (HCC) represents the most frequent form of liver cancer. It evolves from cirrhosis, as the result of a restructuring phase at the end of which dysplastic nodules appear. HCC is the main cause of death in people affected by cirrhosis. The most reliable method for HCC diagnosis, the golden standard, is the needle biopsy, but this is an invasive technique, dangerous for the human body. We develop computerized methods, based on ultrasound images, in order to perform automatic diagnosis of HCC in a noninvasive manner. In our previous research, we elaborated the textural model of HCC, based on classical and advanced texture analysis methods, in combination with traditional classification techniques, which led to a satisfying accuracy. We aim to improve this performance in our current and further research. In this article, we analyzed the role of specific deep learning techniques concerning the automatic recognition of HCC from ultrasound images. We chose the Convolutional Neural Networks (CNN), this method being well known for its performance in the field of image recognition. Thus, CNN are based on artificial neural networks, they also performing image processing operations, such as inner convolutions. In order to evaluate the newly adopted technique, we assessed the classification accuracy achieved in the cases of distinguishing HCC from the cirrhotic parenchyma on which it had evolved, respectively when differentiating HCC from the hemangioma benign liver tumor. We compared the accuracy of CNN with our previous results, based on texture analysis methods and it resulted that CNN yielded better recognition rates than the classical texture analysis techniques, respectively comparable with those provided by the advanced texture analysis methods. However, further improvements will be necessary, which we mention within the last section of this article.
Circulation, Oct 28, 2008
Introduction: Treatment-induced impairment of left ventricular (LV) function is a well-establishe... more Introduction: Treatment-induced impairment of left ventricular (LV) function is a well-established consequence of anthracyclines. Hypothesis: We assessed the hypothesis that treatment with ACE inhi...
Our paper presents an eLearning portal generator environment with powerful MultiMedia facilities,... more Our paper presents an eLearning portal generator environment with powerful MultiMedia facilities, consisting in: advanced multimedia objects handling techniques, synchronization procedures, graphic object oriented data structures, image processing elements (based on texture analysis), moving objects extraction from the video frames, etc. First we present the general design of the e-learning site generator environment and the general scheme of the major .jsp pages, after being detailed some multimedia object handling techniques, as well as the mathematical background used in the synchronization between the moving images and the audio-video sequences.
The main results of this paper establish the superdense unbounded divergence of some discrete bes... more The main results of this paper establish the superdense unbounded divergence of some discrete best approximation operators. 2000 Mathematics Subject Classification: 41A10.
2010 IEEE International Conference on Automation, Quality and Testing, Robotics (AQTR), 2010
This paper is devoted to investigate numerical optimization algorithms of the theory of deformabl... more This paper is devoted to investigate numerical optimization algorithms of the theory of deformable surfaces and to emphasize some of their computerized applications in medical image analysis and prosthetic surgery. After defining the 3D variational deformable model, both in static and dynamic form, an algorithm for finding the optimal deformable surface is presented, together with estimations for its approximation error and a condition for its convergence. Finally, a statistical modeling and a corresponding algorithm applied in surgery are presented.
2006 IEEE International Conference on Automation, Quality and Testing, Robotics, 2006
... Paulina Mitrea*, Alexandru Imbroane** , Alexandru Ioan Mitrea*, Mira Cristiana Anisiu *Techni... more ... Paulina Mitrea*, Alexandru Imbroane** , Alexandru Ioan Mitrea*, Mira Cristiana Anisiu *Technical University Cluj-Napoca, ** Babes-Bolyai University Cluj ... Continuous-Time and Discrete-Time Transformations , Mediamira, Cluj-Napoca, 2005 [3] O. Agratini, I. Chiorean, Gh. ...
2008 IEEE International Conference on Automation, Quality and Testing, Robotics, 2008
This paper is devoted to the mathematical approaches and software implementations in the domain o... more This paper is devoted to the mathematical approaches and software implementations in the domain of deformable models. Based on a general result of calculus of variations, we deduce the Euler-Lagrange-Poisson (ELP) Equation associated to the 2D deformable models, with relevant applications in medical imaging; the optimal solution of these models is found among the solutions (named extremals) of ELP Equation.
2014 IEEE International Conference on Automation, Quality and Testing, Robotics, 2014
ABSTRACT The basic goals of this paper target on the development and implementation of algorithms... more ABSTRACT The basic goals of this paper target on the development and implementation of algorithms which provide the energy-minimizing snakes in parametric form, then in applying them to textural analysis based medical diagnosis. In order to derive these algorithms, we focus on Finite Differences Methods (Explicit and Crank-Nicolson Finite Difference Schemes), widely used in medical image processing applications. We examine the consistency, stability, and convergence rate, proving their increased quality able to provide maximum accuracy when determining the diseased anatomic tissue delimitation in the context of medical images.
Computational and Mathematical Methods in Medicine, 2012
After a brief survey on the parametric deformable models, we develop an iterative method based on... more After a brief survey on the parametric deformable models, we develop an iterative method based on the finite difference schemes in order to obtain energy-minimizing snakes. We estimate the approximation error, the residue, and the truncature error related to the corresponding algorithm, then we discuss its convergence, consistency, and stability. Some aspects regarding the prosthetic sugical methods that implement the above numerical methods are also pointed out.
Applied Medical Informatics, 2019
Viaţa medicală; revistă de informare profesională şi ştiinţifică a cadrelor medii sanitare, 1976
Heart, Lung and Circulation, 2009
Proceeding of 10th …, 2011
1 Introduction The inflammatory bowel diseases (IBD) are a group of disorders that frequently mar... more 1 Introduction The inflammatory bowel diseases (IBD) are a group of disorders that frequently mark the population of the developed countries. Their evolution is frequently chronic, with activation peaks and remission periods, elements that are conditioned by the rapidity of the ...
Springer eBooks, 2010
The main objective of the article is to highlight the role that Web2.0 currently has and could ha... more The main objective of the article is to highlight the role that Web2.0 currently has and could have in the future in supporting the teaching of ICT Design for All. According to this, first the concepts of Web2.0 and eLearning2.0 are clarified and connected. The new way of thinking about eLearning being inspired by the emergence of Web2.0, the term eLearning2.0 was introduced to identify a new paradigm. So, eLearning 2.0, by contrast to eLearning1.0 is built around collaboration, also eLearning2.0 assumes that knowledge is socially constructed. Related to the role of Web2.0 in supporting the teaching of ICT Design for All, the 4 steps involved by the ICT Design For All Teaching Principles are presented and detailed. Finally, some real world examples are shown, as evidence of how the new methods of communication offered by Web2.0 can be used to support students as they learn about Design for All.
International Conference on Electronics, Hardware, Wireless and Optical Communications, Feb 20, 2011
The inflammatory bowel diseases (IBD) are severe, chronic and recurring disorders, requiring cont... more The inflammatory bowel diseases (IBD) are severe, chronic and recurring disorders, requiring continuous patient monitoring. We aim to develop computerized methods for the noninvasive assessment of the bowel inflammation based on ultrasound images. In this work, we study the role of the textural parameters in characterizing different types of inflammatory bowel diseases and the colorectal tumors. Also, the time intensity curves (TIC) are post processed through mathematical modeling, in order to emphasize the behavior of the contrast agent for the considered affections. The relevant textural and TIC parameters are determined through specific methods, and then they are assessed individually and in combination for performing automatic diagnosis. B-mode and contrast-enhanced ultrasound images (CEUS) of biopsied patients are used. The information obtained from the endoscopic images is taken into consideration, as well. The patients were suffering from the following diseases: Crohn's disease, ulcerative recto-colitis, colon cancer. .
HCC (Hepatocellular carcinoma) is the liver cancer form that is the most often met. The actual st... more HCC (Hepatocellular carcinoma) is the liver cancer form that is the most often met. The actual standard for a highly accurate diagnosis of HCC is the biopsy, this being, however, invasive, as well as dangerous. We develop computerized methods, based on advanced image processing, in order to perform automatic, respectively computer aided diagnosis of HCC based on ultrasound images. In this research paper, we analyze the role of several advanced texture analysis specific methods, combined with powerful conventional classifiers, respectively deep learning techniques, for HCC automatic recognition. Regarding the deep learning methods, we focus on Stacked Denoising Autoencoders (SAE), so we study its impact upon the performance of HCC computerized diagnosis. In our experiments, we compare the HCC tumor with both the cirrhotic liver parenchyma on which it evolved and with the hemangioma tumor, the obtained accuracy being around 85%. The actual results are compared, as well, with the previously obtained results in the literature.
Proceedings of 2012 IEEE International Conference on Automation, Quality and Testing, Robotics, 2012
In this paper, we describe briefly the 2D parametric deformable models, then we infer an algorith... more In this paper, we describe briefly the 2D parametric deformable models, then we infer an algorithm, via Crank-Nicolson finite difference scheme for finding the so-called energy-minimizing (i.e. optimal) snake. The residue, the truncature - error and the order of accuracy related to this algorithm are estimated, in order to establish its consistency. We prove that the algorithm leads to better
IFMBE Proceedings, 2009
ABSTRACT This paper is devoted to point out some mathematical methods and techniques in the theor... more ABSTRACT This paper is devoted to point out some mathematical methods and techniques in the theory of deformable models, with applications in medical image analysis. After presenting the definition of 3D-deformable model, some reconstruction methods based on projection operators and discretization methods related to the corresponding evolution equation, are pointed out. Finally, some applications in echographic images are given. KeywordsDeformable variational model-reconstruction methods-projection operators-discretization methods-echographic images
Lecture Notes in Computer Science, 2010
1 Department of Histology, University of Medicine and Pharmacy Iuliu Hatieganu, Cluj-Napoca, Ro... more 1 Department of Histology, University of Medicine and Pharmacy Iuliu Hatieganu, Cluj-Napoca, Romania mcrisan7@yahoo.com, diana_crisan2002@yahoo.com 2 Department of Pharmaceutical Sciences, University of Salerno, Italy ccattani@unisa.it 3 Department of Ultrasonography, ...
2017 10th International Congress on Image and Signal Processing, BioMedical Engineering and Informatics (CISP-BMEI), 2017
Cirrhosis is an important disease, as it can precede liver cancer, and also can lead to death by ... more Cirrhosis is an important disease, as it can precede liver cancer, and also can lead to death by itself. Detecting the severity grades of cirrhosis is a major issue in this context. The best nowadays standard for this purpose is the biopsy, however this procedure is invasive, dangerous for the patient. Also, there is no objective study in order to establish which the cirrhosis grades are. Our research purpose is to discover the cirrhosis grades using computerized methods and to perform non-invasive, computer assisted and automatic diagnosis of the disease evolution phases. Concerning the employed features, we adopted the texture-based methods, able to emphasize those characteristics of the tissue that cannot be detected by the eye of the medical expert. In this paper, we emphasized the role of the CETMCM Matrix concerning the detection of the cirrhosis severity grades. The method was validated by supervised classification, providing a recognition rate above 95%.
6th International Conference on Advancements of Medicine and Health Care through Technology; 17–20 October 2018, Cluj-Napoca, Romania, 2019
Hepatocellular carcinoma (HCC) represents the most frequent form of liver cancer. It evolves from... more Hepatocellular carcinoma (HCC) represents the most frequent form of liver cancer. It evolves from cirrhosis, as the result of a restructuring phase at the end of which dysplastic nodules appear. HCC is the main cause of death in people affected by cirrhosis. The most reliable method for HCC diagnosis, the golden standard, is the needle biopsy, but this is an invasive technique, dangerous for the human body. We develop computerized methods, based on ultrasound images, in order to perform automatic diagnosis of HCC in a noninvasive manner. In our previous research, we elaborated the textural model of HCC, based on classical and advanced texture analysis methods, in combination with traditional classification techniques, which led to a satisfying accuracy. We aim to improve this performance in our current and further research. In this article, we analyzed the role of specific deep learning techniques concerning the automatic recognition of HCC from ultrasound images. We chose the Convolutional Neural Networks (CNN), this method being well known for its performance in the field of image recognition. Thus, CNN are based on artificial neural networks, they also performing image processing operations, such as inner convolutions. In order to evaluate the newly adopted technique, we assessed the classification accuracy achieved in the cases of distinguishing HCC from the cirrhotic parenchyma on which it had evolved, respectively when differentiating HCC from the hemangioma benign liver tumor. We compared the accuracy of CNN with our previous results, based on texture analysis methods and it resulted that CNN yielded better recognition rates than the classical texture analysis techniques, respectively comparable with those provided by the advanced texture analysis methods. However, further improvements will be necessary, which we mention within the last section of this article.
Circulation, Oct 28, 2008
Introduction: Treatment-induced impairment of left ventricular (LV) function is a well-establishe... more Introduction: Treatment-induced impairment of left ventricular (LV) function is a well-established consequence of anthracyclines. Hypothesis: We assessed the hypothesis that treatment with ACE inhi...
Our paper presents an eLearning portal generator environment with powerful MultiMedia facilities,... more Our paper presents an eLearning portal generator environment with powerful MultiMedia facilities, consisting in: advanced multimedia objects handling techniques, synchronization procedures, graphic object oriented data structures, image processing elements (based on texture analysis), moving objects extraction from the video frames, etc. First we present the general design of the e-learning site generator environment and the general scheme of the major .jsp pages, after being detailed some multimedia object handling techniques, as well as the mathematical background used in the synchronization between the moving images and the audio-video sequences.