Maher Ahmed - Academia.edu (original) (raw)

Papers by Maher Ahmed

Recently, the chipless Radio Frequency Identification (RFID) technology has attracted tremendous a... more Recently, the chipless Radio Frequency Identification (RFID) technology has attracted tremendous attention in the market of item identification where the cost is the main concern. However, up to date the technology is at the conceptual level and suffers from a lot of imitations that hinder the technology deployment. The chipless RFID system comprises three major parts which are the reader circuit, the interrogation antennas, and the chipless tags. The contributions of this dissertation are to overcome the challenges that impede the deployment of the chipless RFID system from the perspective of innovating physically modulated tags and developing the reader antenna system. In particular, the system is considered in three novel aspects. The first aspect is the linear physically modulated tags where the tag is interrogated by Ultra Wideband (UWB) signal and the tag inscribed metallic resonators are physically modulating the interrogation frequencies. Therefore, the UWB waveform is modulate...

Alexandria Journal of Pediatrics, 2020

Background Noisy breathing is a very common complaint among children. It may carry a risk for lif... more Background Noisy breathing is a very common complaint among children. It may carry a risk for life-threatening problems. Flexible bronchoscopy (FB) has become one of the most widely used diagnostic tools used by pediatric pulmonologists. Several forces are needed to be explored to help refine its use and reduce its complications. Aim The paper aimed to evaluate the use of pediatric bronchoscopy as a safe diagnostic tool for persistent and/or atypical noisy breathing children, the possible complications, and how it helps to change the management. Patients and methods A total of 100 children, aged from 1 month to 16 years, with persistent and/or noisy breathing were included in a prospective study using FB (May 2016 to May 2019) at a Tertiary Care Medical Center (Sohag University Hospital). The authors evaluated how bronchoscopy contributed to the patients’ diagnosis, what were the complications and limits in the center, and how the authors could deal with them. Results Overall, 37% of patients had malacia disorders, 22% had airway inflammation, 20% had foreign body aspiration, 6% vocal cord dysfunction, 6% subglottic stenosis, 4% tracheal stenosis, 1% subglottic hemangioma, and in three cases, no abnormalities could be detected. Minor complications occurred in 20% of cases; the most common was desaturation (10%), followed by exaggerated cough reflex, laryngeal spasm, and bronchospasm. Conclusion FB provided rapid and definitive diagnosis (confirming, ruling out, and discovering unexpected diagnosis) for the patients. It is a safe procedure and should be considered in the evaluation of children with persistent or atypical noisy breathing.

Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures

ABSTRACT

Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures

ABSTRACT

Portugaliae Electrochimica Acta

Portugaliae Electrochimica Acta

2012 International Conference on Computer and Communication Engineering, 2012

Eprint Arxiv 1110 4369, Oct 19, 2011

In this work, the area and edges spin wave calculations were carried out using the Heisenberg Ham... more In this work, the area and edges spin wave calculations were carried out using the Heisenberg Hamiltonian and the tridiagonal method for the 2D ferromagnetic square lattice stripe, where the SW modes are characterized by a 1D in-plane wave vector qxq_xqx. The results show a general and an unexpected feature that the area and edge spin waves only exist as optic modes. This behavior is also seen in 2D Heisenberg antiferromagnetic square lattice. This absence of the acoustic modes in the 2D square lattice is explained by the fact that the geometry constrains for NN exchange inside the square lattice allow only optical modes. We suggest that this unexpected behavior of spin waves in the 2D square lattice may be useful in realizing an explanation for HTS.

Proceedings Icip International Conference on Image Processing, Oct 1, 2008

In this paper we present a novel distance measure, the Mini- mumLandscapeDistance(MLD).MLDprovide... more In this paper we present a novel distance measure, the Mini- mumLandscapeDistance(MLD).MLDprovidesa non-linear mappingbetweentheelementsin onesequenceto thoseof an- other. Each element in one sequence is mapped to that with the highest neighbourhoodstructuralsimilarity (landscape)in the other sequence within a search window. Experimental re- sults obtained on sequences representing binary images show that MLD is superior to the Euclidean, correlation, and Dy- namic

Proceedings of the 5th Wseas International Conference on Signal Speech and Image Processing, Aug 17, 2005

... Title, A study of the decay {mu} {yields} e{gamma} by the MEGA experiment ... Description/Abs... more ... Title, A study of the decay {mu} {yields} e{gamma} by the MEGA experiment ... Description/Abstract, The MEGA experiment is designed to search for the lepton-flavor number non-conserving rare decay {mu} {yields} {ital e}{gamma}. ...

Most commonly used face recognition algorithms are based on extraction of global features using e... more Most commonly used face recognition algorithms are based on extraction of global features using eigenvalue decomposition of some relational matrix of image intensity values. Real time face recognition applications require a computationally efficient algorithm for eigenvalues generation. Fast principal component analysis (FPCA) is an algorithm for efficient generation of eigenvalues which improves the computational efficiency to O(n2) as compared to

Ieee Pes General Meeting, Jul 1, 2010

2008 IEEE 2nd International Power and Energy Conference, 2008

2009 Transmission & Distribution Conference & Exposition: Asia and Pacific, 2009

2008 IEEE/PES Transmission and Distribution Conference and Exposition, 2008

Recently, the chipless Radio Frequency Identification (RFID) technology has attracted tremendous a... more Recently, the chipless Radio Frequency Identification (RFID) technology has attracted tremendous attention in the market of item identification where the cost is the main concern. However, up to date the technology is at the conceptual level and suffers from a lot of imitations that hinder the technology deployment. The chipless RFID system comprises three major parts which are the reader circuit, the interrogation antennas, and the chipless tags. The contributions of this dissertation are to overcome the challenges that impede the deployment of the chipless RFID system from the perspective of innovating physically modulated tags and developing the reader antenna system. In particular, the system is considered in three novel aspects. The first aspect is the linear physically modulated tags where the tag is interrogated by Ultra Wideband (UWB) signal and the tag inscribed metallic resonators are physically modulating the interrogation frequencies. Therefore, the UWB waveform is modulate...

Alexandria Journal of Pediatrics, 2020

Background Noisy breathing is a very common complaint among children. It may carry a risk for lif... more Background Noisy breathing is a very common complaint among children. It may carry a risk for life-threatening problems. Flexible bronchoscopy (FB) has become one of the most widely used diagnostic tools used by pediatric pulmonologists. Several forces are needed to be explored to help refine its use and reduce its complications. Aim The paper aimed to evaluate the use of pediatric bronchoscopy as a safe diagnostic tool for persistent and/or atypical noisy breathing children, the possible complications, and how it helps to change the management. Patients and methods A total of 100 children, aged from 1 month to 16 years, with persistent and/or noisy breathing were included in a prospective study using FB (May 2016 to May 2019) at a Tertiary Care Medical Center (Sohag University Hospital). The authors evaluated how bronchoscopy contributed to the patients’ diagnosis, what were the complications and limits in the center, and how the authors could deal with them. Results Overall, 37% of patients had malacia disorders, 22% had airway inflammation, 20% had foreign body aspiration, 6% vocal cord dysfunction, 6% subglottic stenosis, 4% tracheal stenosis, 1% subglottic hemangioma, and in three cases, no abnormalities could be detected. Minor complications occurred in 20% of cases; the most common was desaturation (10%), followed by exaggerated cough reflex, laryngeal spasm, and bronchospasm. Conclusion FB provided rapid and definitive diagnosis (confirming, ruling out, and discovering unexpected diagnosis) for the patients. It is a safe procedure and should be considered in the evaluation of children with persistent or atypical noisy breathing.

Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures

ABSTRACT

Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures

ABSTRACT

Portugaliae Electrochimica Acta

Portugaliae Electrochimica Acta

2012 International Conference on Computer and Communication Engineering, 2012

Eprint Arxiv 1110 4369, Oct 19, 2011

In this work, the area and edges spin wave calculations were carried out using the Heisenberg Ham... more In this work, the area and edges spin wave calculations were carried out using the Heisenberg Hamiltonian and the tridiagonal method for the 2D ferromagnetic square lattice stripe, where the SW modes are characterized by a 1D in-plane wave vector qxq_xqx. The results show a general and an unexpected feature that the area and edge spin waves only exist as optic modes. This behavior is also seen in 2D Heisenberg antiferromagnetic square lattice. This absence of the acoustic modes in the 2D square lattice is explained by the fact that the geometry constrains for NN exchange inside the square lattice allow only optical modes. We suggest that this unexpected behavior of spin waves in the 2D square lattice may be useful in realizing an explanation for HTS.

Proceedings Icip International Conference on Image Processing, Oct 1, 2008

In this paper we present a novel distance measure, the Mini- mumLandscapeDistance(MLD).MLDprovide... more In this paper we present a novel distance measure, the Mini- mumLandscapeDistance(MLD).MLDprovidesa non-linear mappingbetweentheelementsin onesequenceto thoseof an- other. Each element in one sequence is mapped to that with the highest neighbourhoodstructuralsimilarity (landscape)in the other sequence within a search window. Experimental re- sults obtained on sequences representing binary images show that MLD is superior to the Euclidean, correlation, and Dy- namic

Proceedings of the 5th Wseas International Conference on Signal Speech and Image Processing, Aug 17, 2005

... Title, A study of the decay {mu} {yields} e{gamma} by the MEGA experiment ... Description/Abs... more ... Title, A study of the decay {mu} {yields} e{gamma} by the MEGA experiment ... Description/Abstract, The MEGA experiment is designed to search for the lepton-flavor number non-conserving rare decay {mu} {yields} {ital e}{gamma}. ...

Most commonly used face recognition algorithms are based on extraction of global features using e... more Most commonly used face recognition algorithms are based on extraction of global features using eigenvalue decomposition of some relational matrix of image intensity values. Real time face recognition applications require a computationally efficient algorithm for eigenvalues generation. Fast principal component analysis (FPCA) is an algorithm for efficient generation of eigenvalues which improves the computational efficiency to O(n2) as compared to

Ieee Pes General Meeting, Jul 1, 2010

2008 IEEE 2nd International Power and Energy Conference, 2008

2009 Transmission & Distribution Conference & Exposition: Asia and Pacific, 2009

2008 IEEE/PES Transmission and Distribution Conference and Exposition, 2008