Ahmed S. Abdullah

Ahmed S. Abdullah

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

View All Publications
18 August 2018 in Symmetry
Verified
Journal Article
Open access
PDF file
MAMohanad Aljanabi
Mohanad Aljanabi
YÖYASA EKŞİOĞLU ÖZOK
YASA EKŞİOĞLU ÖZOK
JRJavad Rahebi
Javad Rahebi
AAAhmed S. Abdullah
Ahmed S. Abdullah
The occurrence rates of melanoma are rising rapidly, which are resulting in higher death rates. However, if the melanoma is diagnosed in Phase I, the survival rates increase. The segmentation of the melanoma is one of the largest tasks to undertake and achieve when considering both beneath and over the segmentation. In this work, a new approach based on the artificial bee colony (ABC) algorithm is proposed for the detection of melanoma from digital images. This method is simple, fast, flexible, and requires fewer parameters compared with other algorithms. The proposed approach is applied on the PH2, ISBI 2016 challenge, the ISBI 2017 challenge, and Dermis datasets. These bases contained images are affected by different abnormalities. The formation of the databases consists of images collected from different sources; they are bases with different types of resolution, lighting, etc., so in the first step, the noise was removed from the images by using morphological filtering. In the next step, the ABC algorithm is used to find the optimum threshold value for the melanoma detection. The proposed approach achieved good results in the conditions of high specificity. The experimental results suggest that the proposed method accomplished higher performance compared to the ground truth images supported by a Dermatologist. For the melanoma detection, the method achieved an average accuracy and Jaccard’s coefficient in the range of 95.24–97.61%, and 83.56–85.25% in these four databases. To show the robustness of this work, the results were compared to existing methods in the literature for melanoma detection. High values for estimation performance confirmed that the proposed melanoma detection is better than other algorithms, which demonstrates the highly differential power of the newly introduced features.

24 August 2019 in Medical & Biological Engineering & Computing
Verified
Journal Article
Closed access
PDF file
AAAhmed S. Abdullah
Ahmed S. Abdullah
JRJavad Rahebi
Javad Rahebi
YÖYasa Ekşioğlu Özok
Yasa Ekşioğlu Özok
MAMohanad Aljanabi
Mohanad Aljanabi

9 May 2018 in Medical & Biological Engineering & Computing
Verified
Journal Article
Closed access
PDF file
AAAhmed S. Abdullah
Ahmed S. Abdullah
YÖYasa Ekşioğlu Özok
Yasa Ekşioğlu Özok
JRJavad Rahebi
Javad Rahebi

9 December 2024 in Journal of Optics
Verified
Journal Article
Closed access
PDF file
SHSadeq A. Hbeeb
Sadeq A. Hbeeb
AAAhmed S. Abdullah
Ahmed S. Abdullah

1 January 2022 in International Journal on Smart Sensing and Intelligent Systems
Verified
Journal Article
Open access
PDF file
AAAhmed S. Abdullah
Ahmed S. Abdullah
SHSadeq Adnan Hbeeb
Sadeq Adnan Hbeeb
The electro-optic effect is considered very important in optical communication systems. The small optical confinement factor is attributed to the weak overlap between the electric field and optical wave and hence the optical signal is not efficiently modulated. In this paper, the problem of the small optical confinement factor in the Mach–Zehnder modulator based on lithium niobate (LN) which is deeply studied. The data were analyzed through a proposed mathematical model to explain the relationship between the change in the ordinary negative refractive index and the confinement factor. The system is improved using a small length of the modulator arm as only 3 to 8 µm, low driving power of about 4 V/µm, a large change in the negative ordinary refractive index of about—0.2 × 10 −7 , and a compact optical modulator. This can reflect a strong optical confinement factor when the electric field is applied to the electrodes of the optical modulator.

1 April 2023 in Bulletin of Electrical Engineering and Informatics
Verified
Journal Article
Open access
PDF file
HAHaider Ali Jasim Alshamary
Haider Ali Jasim Alshamary
AAAhmed S. Abdullah
Ahmed S. Abdullah
SHSadeq Adnan Hbeeb
Sadeq Adnan Hbeeb
Deformation correction and recovery of dynamic magnetic resonance images (DMRI) with low complexity algorithms without compromising image quality is a challenging problem. We proposed a motion estimation deformation-correction compressive sensing (DC-CS) scheme to recover dynamic images from its undersampled measurements. We simplify the complex optimization problem into three sub-problems. The contributions of this research are: introducing a global search strategy instead of the DC registration step, guaranteeing a non-explicit motion estimation that avoids any spatial alignment or registration of the images, and lowering the computational cost to the minimum by using PatchMatch (PM). The simulation result shows that the PM algorithm accelerates the recovery time without losing the quality in comparison with the DC algorithm.