George A. Papakostas

Prof. Dr. George A. Papakostas

International Hellenic University
orcid

Research Focus & Metrics

Academic Career Length

23Years (2004-Present)

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

Representative Publications

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7 December 2019 in Journal of Imaging
Verified
Journal Article
Open access
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EMEfthimia Mavridou
Efthimia Mavridou
Eleni VrochidouEleni Vrochidou
Eleni Vrochidou
George A. PapakostasGeorge A. Papakostas
George A. Papakostas
THEODORE PACHIDISTHEODORE PACHIDIS
THEODORE PACHIDIS
Vassilis KaburlasosVassilis Kaburlasos
Vassilis Kaburlasos
Machine vision for precision agriculture has attracted considerable research interest in recent years. The aim of this paper is to review the most recent work in the application of machine vision to agriculture, mainly for crop farming. This study can serve as a research guide for the researcher and practitioner alike in applying cognitive technology to agriculture. Studies of different agricultural activities that support crop harvesting are reviewed, such as fruit grading, fruit counting, and yield estimation. Moreover, plant health monitoring approaches are addressed, including weed, insect, and disease detection. Finally, recent research efforts considering vehicle guidance systems and agricultural harvesting robots are also reviewed.

15 June 2023 in IEEE Access
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Journal Article
Open access
KHKhalid M. Hosny
Khalid M. Hosny
WEWalaa M. El-Hady
Walaa M. El-Hady
FSFarid M. Samy
Farid M. Samy
Eleni VrochidouEleni Vrochidou
Eleni Vrochidou
George A. PapakostasGeorge A. Papakostas
George A. Papakostas
Plant diseases are one of the primary causes of decreased agricultural production quality and quantity. With ongoing changes in plant structure and cultivation techniques, new diseases are constantly arising on plant leaves. Thus, accurate classification and detection of plant leaf diseases in their early stages will limit the spread of the infection and support the healthy development of plant production. This work proposes a novel lightweight deep convolutional neural network (CNN) model for obtaining high-level hidden feature representations. The deep features are then fused with traditional handcrafted local binary pattern (LBP) features to capture local texture information in plant leaf images. The proposed model is trained and tested on three publicly available datasets (Apple Leaf, Tomato Leaf, and Grape Leaf). On the three datasets, the proposed approach achieves 99%, 96.6%, and 98.5% validation accuracies, respectively, and 98.8%, 96.5%, and 98.3% test accuracies, respectively. The results of the experiments show that the proposed approach can provide a better control solution for plant diseases.

1 October 2013 in Pattern Recognition Letters
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Journal Article
Closed access
George A. PapakostasGeorge A. Papakostas
George A. Papakostas
AHA.G. Hatzimichailidis
A.G. Hatzimichailidis
Vassilis KaburlasosVassilis Kaburlasos
Vassilis Kaburlasos

9 February 2012 in International Journal of Intelligent Systems
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Journal Article
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George A. PapakostasGeorge A. Papakostas
George A. Papakostas
George A. PapakostasGeorge A. Papakostas
George A. Papakostas
Vassilis KaburlasosVassilis Kaburlasos
Vassilis Kaburlasos
A novel distance measure between two intuitionistic fuzzy sets (IFSs) is proposed in this paper. The introduced measure formulates the information of each set in matrix structure, where matrix norms in conjunction with fuzzy implications can be applied to measure the distance between the IFSs. The advantage of this novel distance measure is its flexibility, which permits different fuzzy implications to be incorporated by extending its applicability to several applications where the most appropriate implication is used. Moreover, the proposed distance might be expressed equivalently by using either intuitionistic fuzzy sets or interval‐valued fuzzy sets. Appropriate experimental configurations have taken place to compare the proposed distance measure with similar distance measures from the literature, by applying them to several pattern recognition problems. The results are very promising because the performance of the new distance measure outperforms the corresponding performance of well‐known IFSs measures, by recognizing the patterns correctly and with high degree of confidence.

30 April 2021 in Electronics
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Journal Article
Open access
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KHKhalid M. Hosny
Khalid M. Hosny
STSara Tarik
Sara Tarik
MDMohamed M. Darwish
Mohamed M. Darwish
George A. PapakostasGeorge A. Papakostas
George A. Papakostas
In the age of Information Technology, the day-life required transmitting millions of images between users. Securing these images is essential. Digital image encryption is a well-known technique used in securing image content. In image encryption techniques, digital images are converted into noise images using secret keys, where restoring them to their originals required the same keys. Most image encryption techniques depend on two steps: confusion and diffusion. In this work, a new algorithm presented for image encryption using a hyperchaotic system and Fibonacci Q-matrix. The original image is confused in this algorithm, utilizing randomly generated numbers by the six-dimension hyperchaotic system. Then, the permutated image diffused using the Fibonacci Q-matrix. The proposed image encryption algorithm tested using noise and data cut attacks, histograms, keyspace, and sensitivity. Moreover, the proposed algorithm’s performance compared with several existing algorithms using entropy, correlation coefficients, and robustness against attack. The proposed algorithm achieved an excellent security level and outperformed the existing image encryption algorithms.

24 May 2023 in Electronics
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Journal Article
Open access
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Kyriaki A TycholaKyriaki A Tychola
Kyriaki A Tychola
TKTheofanis Kalampokas
Theofanis Kalampokas
George A. PapakostasGeorge A. Papakostas
George A. Papakostas
Quantum computing has been proven to excel in factorization issues and unordered search problems due to its capability of quantum parallelism. This unique feature allows exponential speed-up in solving certain problems. However, this advantage does not apply universally, and challenges arise when combining classical and quantum computing to achieve acceleration in computation speed. This paper aims to address these challenges by exploring the current state of quantum machine learning and benchmarking the performance of quantum and classical algorithms in terms of accuracy. Specifically, we conducted experiments with three datasets for binary classification, implementing Support Vector Machine (SVM) and Quantum SVM (QSVM) algorithms. Our findings suggest that the QSVM algorithm outperforms classical SVM on complex datasets, and the performance gap between quantum and classical models increases with dataset complexity, as simple models tend to overfit with complex datasets. While there is still a long way to go in terms of developing quantum hardware with sufficient resources, quantum machine learning holds great potential in areas such as unsupervised learning and generative models. Moving forward, more efforts are needed to explore new quantum learning models that can leverage the power of quantum mechanics to overcome the limitations of classical machine learning.