Simona Moldovanu

Dr. Simona Moldovanu

Dunarea de Jos Univerity of Galati
orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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20 October 2021 in Cancers
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Journal Article
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Simona MoldovanuSimona Moldovanu
Simona Moldovanu
FDFELICIA ANISOARA MICHIS DAMIAN
FELICIA ANISOARA MICHIS DAMIAN
KBKeka Biswas
Keka Biswas
ACAnisia Culea-Florescu
Anisia Culea-Florescu
Luminita MoraruLuminita Moraru
Luminita Moraru
(1) Background: An approach for skin cancer recognition and classification by implementation of a novel combination of features and two classifiers, as an auxiliary diagnostic method, is proposed. (2) Methods: The predictions are made by k-nearest neighbor with a 5-fold cross validation algorithm and a neural network model to assist dermatologists in the diagnosis of cancerous skin lesions. As a main contribution, this work proposes a descriptor that combines skin surface fractal dimension and relevant color area features for skin lesion classification purposes. The surface fractal dimension is computed using a 2D generalization of Higuchi’s method. A clustering method allows for the selection of the relevant color distribution in skin lesion images by determining the average percentage of color areas within the nevi and melanoma lesion areas. In a classification stage, the Higuchi fractal dimensions (HFDs) and the color features are classified, separately, using a kNN-CV algorithm. In addition, these features are prototypes for a Radial basis function neural network (RBFNN) classifier. The efficiency of our algorithms was verified by utilizing images belonging to the 7-Point, Med-Node, and PH2 databases; (3) Results: Experimental results show that the accuracy of the proposed RBFNN model in skin cancer classification is 95.42% for 7-Point, 94.71% for Med-Node, and 94.88% for PH2, which are all significantly better than that of the kNN algorithm. (4) Conclusions: 2D Higuchi’s surface fractal features have not been previously used for skin lesion classification purpose. We used fractal features further correlated to color features to create a RBFNN classifier that provides high accuracies of classification.

21 December 2022 in Electronics
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Journal Article
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MWMing-Yue Wang
Ming-Yue Wang
Anjan BiswasAnjan Biswas
Anjan Biswas
YYYakup Yildirim
Yakup Yildirim
Luminita MoraruLuminita Moraru
Luminita Moraru
Simona MoldovanuSimona Moldovanu
Simona Moldovanu
HAHashim Alshehri
Hashim Alshehri
This paper addresses the newly proposed concatenation model by the usage of trial equation approach. The concatenation is a chain model that is a combination of the nonlinear Schrodinger’s equation, Lakshmanan–Porsezian–Daniel model as well as the Sasa–Satsuma equation. The recovered solutions are displayed in terms of dark solitons, singular solitons, cnoidal waves and singular periodic waves. The trial equation approach enables to recover a wide spectrum of solutions to the governing model. The numerical schemes give a visual perspective to the solutions derived analytically.

2 November 2022 in Mathematics
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Journal Article
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ISIslam Samir
Islam Samir
AAAhmed Arnous
Ahmed Arnous
YYYakup Yıldırım
Yakup Yıldırım
Anjan BiswasAnjan Biswas
Anjan Biswas
Luminita MoraruLuminita Moraru
Luminita Moraru
Simona MoldovanuSimona Moldovanu
Simona Moldovanu
The current paper considers the enhanced Kudryashov’s technique to retrieve solitons with a governing model having cubic-quintic-septic-nonic and quadrupled structures of self-phase modulation. The results prove that it is redundant to extend the self-phase modulation beyond cubic-quintic nonlinearity or dual-power law of nonlinearity.

28 December 2023 in Journal of Imaging
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TGTabacaru Gigi
Tabacaru Gigi
Simona MoldovanuSimona Moldovanu
Simona Moldovanu
ERElena Răducan
Elena Răducan
Marian BarbuMarian Barbu
Marian Barbu
Ensemble learning is a process that belongs to the artificial intelligence (AI) field. It helps to choose a robust machine learning (ML) model, usually used for data classification. AI has a large connection with image processing and feature classification, and it can also be successfully applied to analyzing fundus eye images. Diabetic retinopathy (DR) is a disease that can cause vision loss and blindness, which, from an imaging point of view, can be shown when screening the eyes. Image processing tools can analyze and extract the features from fundus eye images, and these corroborate with ML classifiers that can perform their classification among different disease classes. The outcomes integrated into automated diagnostic systems can be a real success for physicians and patients. In this study, in the form image processing area, the manipulation of the contrast with the gamma correction parameter was applied because DR affects the blood vessels, and the structure of the eyes becomes disorderly. Therefore, the analysis of the texture with two types of entropies was necessary. Shannon and fuzzy entropies and contrast manipulation led to ten original features used in the classification process. The machine learning library PyCaret performs complex tasks, and the empirical process shows that of the fifteen classifiers, the gradient boosting classifier (GBC) provides the best results. Indeed, the proposed model can classify the DR degrees as normal or severe, achieving an accuracy of 0.929, an F1 score of 0.902, and an area under the curve (AUC) of 0.941. The validation of the selected model with a bootstrap statistical technique was performed. The novelty of the study consists of the extraction of features from preprocessed fundus eye images, their classification, and the manipulation of the contrast in a controlled way.

22 May 2021 in Diagnostics
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Journal Article
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Simona MoldovanuSimona Moldovanu
Simona Moldovanu
COCristian Obreja
Cristian Obreja
KBKeka Biswas
Keka Biswas
Luminita MoraruLuminita Moraru
Luminita Moraru
In the automatic detection framework, there have been many attempts to develop models for real-time melanoma detection. To effectively discriminate benign and malign skin lesions, this work investigates sixty different architectures of the Feedforward Back Propagation Network (FFBPN), based on shape asymmetry for an optimal structural design that includes both the hidden neuron number and the input data selection. The reason for the choice of shape asymmetry was based on the 5–10% disagreement between dermatologists regarding the efficacy of asymmetry in the diagnosis of malignant melanoma. Asymmetry is quantified based on lesion shape (contour), moment of inertia of the lesion shape and histograms. The FFBPN has a high architecture flexibility, which indicates it as a favorable tool to avoid the over-parameterization of the ANN and, equally, to discard those redundant input datasets that usually result in poor test performance. The FFBPN was tested on four public image datasets containing melanoma, dysplastic nevus and nevus images. Experimental results on multiple benchmark data sets demonstrate that asymmetry A2 is a meaningful feature for skin lesion classification, and FFBPN with 16 neurons in the hidden layer can model the data without compromising prediction accuracy.

26 February 2023 in Heliyon
Verified
Journal Article
Open access
AAAhmed Arnous
Ahmed Arnous
ABAnjan Biswas
Anjan Biswas
AKAbdul H. Kara
Abdul H. Kara
YYYakup Yıldırım
Yakup Yıldırım
Luminita MoraruLuminita Moraru
Luminita Moraru
Abdulah A AlghamdiAbdulah A Alghamdi
Abdulah A Alghamdi
The current paper implements three elegant approaches to recover a complete spectrum of optical solitons to the Radhakrishnan-Kundu-Lakshmanan equation with dual-power law of nonlinear refractive index. The conservation laws are also recovered by the usage of multipliers approach. The parameter constraints for the existence of such solitons are also enumerated. The numerical simulations of the recovered soliton solutions are also presented.