A novel design of ultra-wideband (UWB) monopole antenna is proposed with small size for UWB appli... more A novel design of ultra-wideband (UWB) monopole antenna is proposed with small size for UWB applications. An equivalent circuit for the proposed monopole antenna is obtained using the Advanced Design System (ADS). A parametric study for the major effective parameters of the antenna is done to study the effect of these parameters and get the optimized values of the antenna parameters. An UWB power divider circuit is designed to be used for exciting 2x1 and 4x1 linear antenna arrays to increase the antenna gain. The antenna element, UWB power divider and antenna arrays are simulated using CST-Microwave Studio and fabricated on FR-4 substrate with dielectric constant of 4.5 and thickness of 1.5 mm. The average gain for the two-element antenna array is about 5.3 dBi and reaches to7.15 dBi for the four-element antenna array, over the whole UWB frequency range. A good agreement between the measured and the simulated results for the antenna element, power divider and antenna arrays is appe...
A proposed design of ultra-wideband (UWB) monopole antenna has been presented to cover frequency ... more A proposed design of ultra-wideband (UWB) monopole antenna has been presented to cover frequency range 2.49–14.42 GHz with small size. An equivalent circuit model with the parameter values of the optimized UWB antenna has been modeled. Moreover, a compatible lumped-elements utilized in equivalent circuit modeling for the proposed monopole antenna is established using the Advanced Design System (ADS). An UWB feeding network circuit has been designed in order to be used for exciting 2x1 and 4x1 linear antenna array. The measured and simulated results for the proposed feed network has a good return loss, isolation and power division ratio at all ports within the whole UWB frequency range. Two and four element UWB linear antenna arrays are presented. The average gain for the two-element antenna array is about 5.3 dBi and reaches to7.15 dBi for the four-element antenna array, over the whole UWB frequency range. A good agreement between the measured and the simulated results of all parame...
A novel design of ultra-wideband (UWB) monopole antenna is proposed with small size for UWB appli... more A novel design of ultra-wideband (UWB) monopole antenna is proposed with small size for UWB applications. An equivalent circuit for the proposed monopole antenna is obtained using the Advanced Design System (ADS). A parametric study for the major effective parameters of the antenna is done to study the effect of these parameters and get the optimized values of the antenna parameters. An UWB power divider circuit is designed to be used for exciting 2x1 and 4x1 linear antenna arrays to increase the antenna gain. The antenna element, UWB power divider and antenna arrays are simulated using CST-Microwave Studio and fabricated on FR-4 substrate with dielectric constant of 4.5 and thickness of 1.5 mm. The average gain for the two-element antenna array is about 5.3 dBi and reaches to7.15 dBi for the four-element antenna array, over the whole UWB frequency range. A good agreement between the measured and the simulated results for the antenna element, power divider and antenna arrays is appe...
ــــــــــــــــــــــــــــــــــــــــــــ ABSTRACT Purpose: To compare the final clearance of ... more ــــــــــــــــــــــــــــــــــــــــــــ ABSTRACT Purpose: To compare the final clearance of stone middle ureter treated by non- stented Shock wave lithotripsy (SWL) ventral technique with ureteroscopic
Beaucoup semblent penser que le monde contemporain dans lequel nous vivons est domine par l’emerg... more Beaucoup semblent penser que le monde contemporain dans lequel nous vivons est domine par l’emergence de ce qu’on appelle communement le « choc des civilisations ». Les partisans de ce discours ont trouve la confirmation de leurs points de vue en montrant l’hostilite et l’animosite grandissantes entre les regions culturelles, surtout entre le monde islamique et le monde occidental, mais aussi au-dela – ce qui a defini les 25 dernieres annees du XXe siecle et la premiere decennie du XXIe siecle.
In the views of many, the contemporary world in which we live appears to be marked most prominent... more In the views of many, the contemporary world in which we live appears to be marked most prominently by the emergence of what is regularly referred to as “a clash of civilizations”. Proponents of the discourse of a clash have sought confirmation of their views by pointing to the increasing hostility and animosity between cultural regions—most obviously between the Islamic and Western worlds—that has defined the last quarter of the twentieth and the first decade of the twenty-first centuries.
2010 IEEE Antennas and Propagation Society International Symposium, 2010
W. Swelam(1)*, M. Ali Soliman(2), Ali Gomaa(2), TE Taha(3) ... (1) RF/Microwave and Photonics Gro... more W. Swelam(1)*, M. Ali Soliman(2), Ali Gomaa(2), TE Taha(3) ... (1) RF/Microwave and Photonics Group, Dep. of ECE, University of Waterloo, Waterloo, Ontario, Canada. E-mail: wswelam@gmail.com ... (2) Shobraa Faculty of Engineering, Benha University, Cairo, ...
In this paper, a random Low-Density Parity-Check (LDPC) code is proposed for Noncontiguous Orthog... more In this paper, a random Low-Density Parity-Check (LDPC) code is proposed for Noncontiguous Orthogonal Frequency Division Multiplexing (NC-OFDM) Cognitive Radio (CR) systems. Unlike other encoding schemes which achieve a system code rate of only 1/4 when half of the subcarriers are active, the proposed scheme achieves a system code rate of 1/2. The LDPC code is used to enhance the data transmission rate. A new channel model comprised of a binary erasure channel concatenated with an uncorrelated fading channel and an AWGN channel is adopted for NC-OFDM CR systems. Moreover, the adopted channel model is employed with density evolution algorithm to obtain good degree distribution pairs for the LDPC code. Thereafter, a modified shortest-path algorithm is used to construct the parity-check matrix for the LDPC code. Simulation results show that the proposed LDPC code performs well in terms of both error rate and data transmission rate.
Plasma malondialdehyde (MDA) (an indicator of lipid peroxidation) was determined in random sample... more Plasma malondialdehyde (MDA) (an indicator of lipid peroxidation) was determined in random samples of workers (age range 25-60 years) exposed to silica dust (n = 31, mean exposure duration 21.3 +/- 8.3 years) or asbestos dust (n = 59, mean exposure duration 15.6 +/- 4.5 years) and in 52 age-matched healthy male controls. MDA levels of both exposed groups were significantly higher than that of the controls and were significantly higher among workers exposed to asbestos than among those exposed to silica dusts. Neither age nor smoking was related to MDA levels among both controls and exposed workers; among the latter group MDA was not significantly correlated with duration of exposure. Mean MDA levels of exposed workers with radiographic signs of lung fibrosis or pleural thickening and of those without such signs were not significantly different, except in the case of asbestos-exposed workers where it was significantly less than that of those without such signs. Differences between mean durations of dust exposure of workers with radiographic signs of lung fibrosis and those without such signs were statistically insignificant. The results suggest the possible involvement of lipid peroxidation on exposure to silica or asbestos dusts in humans and possible development of antioxidant mechanism(s) on prolonged dust exposure and support the opinion that development of pneumoconiosis depends on susceptibility factor(s).
Objective: The aim of work is to evaluate the efficacy and safety of the Dornier lithotripter S I... more Objective: The aim of work is to evaluate the efficacy and safety of the Dornier lithotripter S II system in the treatment of renal calculi. Patients and methods: One hundred patients having renal stones who are candidates for SWL treatment at Bab El-shaa'rya university Hospital, from Apr. 2010 to Mar. 2011, including 54 males and 46 females, ranging in age from 2.5 years to 67 years old (mean age: 40.2 years). Results: The initial fragmentation rate was 96%. The stone-free rate for stones of< 10 mm was 100%, for 11–20 mm was 87.6% and ...
A novel design of ultra-wideband (UWB) monopole antenna is proposed with small size for UWB appli... more A novel design of ultra-wideband (UWB) monopole antenna is proposed with small size for UWB applications. An equivalent circuit for the proposed monopole antenna is obtained using the Advanced Design System (ADS). A parametric study for the major effective parameters of the antenna is done to study the effect of these parameters and get the optimized values of the antenna parameters. An UWB power divider circuit is designed to be used for exciting 2x1 and 4x1 linear antenna arrays to increase the antenna gain. The antenna element, UWB power divider and antenna arrays are simulated using CST-Microwave Studio and fabricated on FR-4 substrate with dielectric constant of 4.5 and thickness of 1.5 mm. The average gain for the two-element antenna array is about 5.3 dBi and reaches to7.15 dBi for the four-element antenna array, over the whole UWB frequency range. A good agreement between the measured and the simulated results for the antenna element, power divider and antenna arrays is appe...
A proposed design of ultra-wideband (UWB) monopole antenna has been presented to cover frequency ... more A proposed design of ultra-wideband (UWB) monopole antenna has been presented to cover frequency range 2.49–14.42 GHz with small size. An equivalent circuit model with the parameter values of the optimized UWB antenna has been modeled. Moreover, a compatible lumped-elements utilized in equivalent circuit modeling for the proposed monopole antenna is established using the Advanced Design System (ADS). An UWB feeding network circuit has been designed in order to be used for exciting 2x1 and 4x1 linear antenna array. The measured and simulated results for the proposed feed network has a good return loss, isolation and power division ratio at all ports within the whole UWB frequency range. Two and four element UWB linear antenna arrays are presented. The average gain for the two-element antenna array is about 5.3 dBi and reaches to7.15 dBi for the four-element antenna array, over the whole UWB frequency range. A good agreement between the measured and the simulated results of all parame...
A novel design of ultra-wideband (UWB) monopole antenna is proposed with small size for UWB appli... more A novel design of ultra-wideband (UWB) monopole antenna is proposed with small size for UWB applications. An equivalent circuit for the proposed monopole antenna is obtained using the Advanced Design System (ADS). A parametric study for the major effective parameters of the antenna is done to study the effect of these parameters and get the optimized values of the antenna parameters. An UWB power divider circuit is designed to be used for exciting 2x1 and 4x1 linear antenna arrays to increase the antenna gain. The antenna element, UWB power divider and antenna arrays are simulated using CST-Microwave Studio and fabricated on FR-4 substrate with dielectric constant of 4.5 and thickness of 1.5 mm. The average gain for the two-element antenna array is about 5.3 dBi and reaches to7.15 dBi for the four-element antenna array, over the whole UWB frequency range. A good agreement between the measured and the simulated results for the antenna element, power divider and antenna arrays is appe...
ــــــــــــــــــــــــــــــــــــــــــــ ABSTRACT Purpose: To compare the final clearance of ... more ــــــــــــــــــــــــــــــــــــــــــــ ABSTRACT Purpose: To compare the final clearance of stone middle ureter treated by non- stented Shock wave lithotripsy (SWL) ventral technique with ureteroscopic
Beaucoup semblent penser que le monde contemporain dans lequel nous vivons est domine par l’emerg... more Beaucoup semblent penser que le monde contemporain dans lequel nous vivons est domine par l’emergence de ce qu’on appelle communement le « choc des civilisations ». Les partisans de ce discours ont trouve la confirmation de leurs points de vue en montrant l’hostilite et l’animosite grandissantes entre les regions culturelles, surtout entre le monde islamique et le monde occidental, mais aussi au-dela – ce qui a defini les 25 dernieres annees du XXe siecle et la premiere decennie du XXIe siecle.
In the views of many, the contemporary world in which we live appears to be marked most prominent... more In the views of many, the contemporary world in which we live appears to be marked most prominently by the emergence of what is regularly referred to as “a clash of civilizations”. Proponents of the discourse of a clash have sought confirmation of their views by pointing to the increasing hostility and animosity between cultural regions—most obviously between the Islamic and Western worlds—that has defined the last quarter of the twentieth and the first decade of the twenty-first centuries.
2010 IEEE Antennas and Propagation Society International Symposium, 2010
W. Swelam(1)*, M. Ali Soliman(2), Ali Gomaa(2), TE Taha(3) ... (1) RF/Microwave and Photonics Gro... more W. Swelam(1)*, M. Ali Soliman(2), Ali Gomaa(2), TE Taha(3) ... (1) RF/Microwave and Photonics Group, Dep. of ECE, University of Waterloo, Waterloo, Ontario, Canada. E-mail: wswelam@gmail.com ... (2) Shobraa Faculty of Engineering, Benha University, Cairo, ...
In this paper, a random Low-Density Parity-Check (LDPC) code is proposed for Noncontiguous Orthog... more In this paper, a random Low-Density Parity-Check (LDPC) code is proposed for Noncontiguous Orthogonal Frequency Division Multiplexing (NC-OFDM) Cognitive Radio (CR) systems. Unlike other encoding schemes which achieve a system code rate of only 1/4 when half of the subcarriers are active, the proposed scheme achieves a system code rate of 1/2. The LDPC code is used to enhance the data transmission rate. A new channel model comprised of a binary erasure channel concatenated with an uncorrelated fading channel and an AWGN channel is adopted for NC-OFDM CR systems. Moreover, the adopted channel model is employed with density evolution algorithm to obtain good degree distribution pairs for the LDPC code. Thereafter, a modified shortest-path algorithm is used to construct the parity-check matrix for the LDPC code. Simulation results show that the proposed LDPC code performs well in terms of both error rate and data transmission rate.
Plasma malondialdehyde (MDA) (an indicator of lipid peroxidation) was determined in random sample... more Plasma malondialdehyde (MDA) (an indicator of lipid peroxidation) was determined in random samples of workers (age range 25-60 years) exposed to silica dust (n = 31, mean exposure duration 21.3 +/- 8.3 years) or asbestos dust (n = 59, mean exposure duration 15.6 +/- 4.5 years) and in 52 age-matched healthy male controls. MDA levels of both exposed groups were significantly higher than that of the controls and were significantly higher among workers exposed to asbestos than among those exposed to silica dusts. Neither age nor smoking was related to MDA levels among both controls and exposed workers; among the latter group MDA was not significantly correlated with duration of exposure. Mean MDA levels of exposed workers with radiographic signs of lung fibrosis or pleural thickening and of those without such signs were not significantly different, except in the case of asbestos-exposed workers where it was significantly less than that of those without such signs. Differences between mean durations of dust exposure of workers with radiographic signs of lung fibrosis and those without such signs were statistically insignificant. The results suggest the possible involvement of lipid peroxidation on exposure to silica or asbestos dusts in humans and possible development of antioxidant mechanism(s) on prolonged dust exposure and support the opinion that development of pneumoconiosis depends on susceptibility factor(s).
Objective: The aim of work is to evaluate the efficacy and safety of the Dornier lithotripter S I... more Objective: The aim of work is to evaluate the efficacy and safety of the Dornier lithotripter S II system in the treatment of renal calculi. Patients and methods: One hundred patients having renal stones who are candidates for SWL treatment at Bab El-shaa'rya university Hospital, from Apr. 2010 to Mar. 2011, including 54 males and 46 females, ranging in age from 2.5 years to 67 years old (mean age: 40.2 years). Results: The initial fragmentation rate was 96%. The stone-free rate for stones of< 10 mm was 100%, for 11–20 mm was 87.6% and ...
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