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Chinese Physics B 2022年第1期31卷 626-630页

作者： A.Abdel Moez Ahmed I.Ali a.tayel Solid State Physics Department Physical Research DivisionNational Research Centre(NRC)33 El Bohouth StreetDokkiGiza 12622Egypt Basic Science Department Faculty of Faculty of Technology and EducationHelwan UniversityKobry El-QopaCairo 11281Egypt

Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)single crystals were grown by using the traveling-solvent floating zone(TSFZ)*** temperature was increased to avoid the bubbles and cracks which may be formed during the preparation of the ingot *** have started with the flux higher than the normal to avoid the bubbles and make good treatment for the solid-liquid *** structures of both Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)were studied by using x-ray diffraction(XRD).Optical properties for C12A7 and Y-C12A7 single crystals have been studied in order to determine the optical parameters such as optical energy gap(Eg),refractive index n,oscillating energy(Eo),dispersion energy(Ed),volume energy loss function(VELF),and surface energy loss function(SELF).Finally,a new result for these samples is that the third-order nonlinear optical susceptibility(χ(3))was *** results have been discussed with effect of Y-doping on the C12A7 single crystals for optical and industrial applications.

关键词： syntheses Ca_(12)Al_(14)O_(33)(C12A7)single crystals Y-doping optical parameters dielectric results nonlinear optical susceptibility

Robust design and analysis for opto-mechanical two array laser warning system

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Defence Technology(防务技术) 2023年第9期27卷 46-52页

作者： Mazhar tayel Mohamed Shehata Mohamed Mabrouk Abdlarhman Adel Mohamed Shady Shokry Mostafa Alshershby Faculty of Engineering Alexandria UniversityAlexandriaEgypt Egyptian Air Defense Collage AlexandriaEgypt Laser and Optoelectronics Department Technical Research CenterEgypt

In the past three decades,laser warning systems(LWS)have emerged in great importance,as the development of laser-guided weapons,such as airborne Hellfire missiles,has increased,posing an imminent threat to vital areas and *** laser warning station(LWS)can detect,classify,identify,and give alarm from laser threat at a very short time with high ***,the designers of this system must take into account the detectability and field of view to cover the area to be *** main contribution in this research is an analytical design of LWS that consists of 24 detector elements,distributed in two arrays(2×12)***,calculating the best distance between the detectors according to the laser beam spot *** addition,enhancement laser warring sensor detection capability and detection performance FOV between the detectors to increase coverage area up to 360°.Moreover,decreasing dead zone area between the laser detectors *** calculations and illustrations made to reach the best systematic design.

关键词： LWS Field of view Detector elements

A Triple-Channel Encrypted Hybrid Fusion Technique to Improve Security of Medical Images

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Computers, Materials & Continua 2021年第7期68卷 431-446页

作者： Ahmed S.Salama Mohamed Amr Mokhtar Mazhar B.tayel Esraa Eldesouky Ahmed Ali Future University in Egypt CairoEgypt Cairo Higher Institute for Engineering Computer Science and ManagementCairoEgypt Department of Electrical Engineering Faculty of EngineeringAlexandria UniversityAlexandria21544Egypt Department of Computer Science Faculty of Computers and InformaticsSuez Canal UniversityIsmailia CityEgypt Higher Future Institute for Specialized Technological Studies CairoEgypt Department of Computer Science College of Computer Engineering and SciencesPrince Sattam Bin Abdulaziz UniversityAl-Kharj11942Saudi Arabia

Assuring medical images protection and robustness is a compulsory necessity *** this paper,a novel technique is proposed that fuses the wavelet-induced multi-resolution decomposition of the Discrete Wavelet Transform(DWT)with the energy compaction of the Discrete Wavelet Transform(DCT).The multi-level Encryption-based Hybrid Fusion Technique(EbhFT)aims to achieve great advances in terms of imperceptibility and security of medical images.A DWT disintegrated sub-band of a cover image is reformed simultaneously using the DCT ***,a 64-bit hex key is employed to encrypt the host image as well as participate in the second key creation process to encode the ***,a PN-sequence key is formed along with a supplementary key in the third layer of the ***,the watermarked image is generated by enclosing both keys into DWT and DCT *** fusions ability of the proposed EbHFT technique makes the best use of the distinct privileges of using both DWT and DCT *** order to validate the proposed technique,a standard dataset of medical images is *** results show higher performance of the visual quality(i.e.,57.65)for the watermarked forms of all types of medical *** addition,EbHFT robustness outperforms an existing scheme tested for the same dataset in terms of Normalized Correlation(NC).Finally,extra protection for digital images from against illegal replicating and unapproved tampering using the proposed technique.

关键词： Medical image processing digital image watermarking discrete wavelet transforms discrete cosine transform encryption image fusion hybrid fusion technique

Anaerobic digestion for waste water poultry manure by UBF reactor

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Journal of Environmental Sciences 1997年第2期9卷 24-36页

作者： Ghanem I.I.Ibrahim Gu Guowei Zhu Jinfu tayel,S.A. Khairy M.F.A. El-Shimi,S.A. Agricultural Engineering Research Institute Agricultural Research CenterMinistry Agriculture DukkiGizaEgypt School of Environmental Engineering Tongji UniversityShanghai200092China Agricultural Engineering Deptartment Faculty of AgricultureAt Azhar UniversityCairoEgypt Soil and Water Research Institute Agricultural Research CentreGizaEgypt

In this experiment the performance of UBF process treatment for wastewater chicken manure was tested under the condition of constant temperature of 35℃ and the volume of UBF is 4 liters. The experiment covered two stages: the first was start up with phase I and phase II, the second was steady state. The following results average of operation period were obtained: (1) During the period of start up phase I operation the biogas production rate 0.39v/(***) at the volumetric COD loading rate of 2.97 kg COD/(m 3.d) with COD removal 76.85% and hydraulic retention time of 10.04 hours and phase II the biogas production rate 3.86 v/(***) at the volume loading rate 11.69 kg COD/(m 3.d) have been achieved with COD removal 82.47% and HRT 16.45 hours. UBF process had resistance to the quantitative shock load. (2) During the steady state operation, the biogas production rate 9.83v/(***) at loading rate of 28.85 kg COD/(m 3.d) and COD removal efficiency 80.03% and hydraulic retention time of 18.73 hours have been achieved for this reactor. The operation of UBF reactor was very stable.

关键词： anaerobic digestion UBF reactor poultry manure chicken manure waste water.

Effects of drip irrigation circuit design and lateral line lengths: I—On pressure and friction loss

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Agricultural Sciences 2012年第3期3卷 392-399页

作者： Mohamed tayel David Lightfoot Hani Mansour Southern Illinois University Carbondale Carbondale USA WRFI Department National Research Center (NRC) Giza Egypt WRFI Department National Research Center (NRC) Giza Egypt

Laboratory tests were conducted at the Irrigation Devices and Equipment’s Test Laboratory, Agricultural Engineering Research Institute, Agriculture Research Center, Giza, Egypt. The experimental design of laboratory experiments was split in randomized complete block design with three replicates. Laboratory tests carried out on three irrigation lateral lines of 40, 60, 80 m under the following three drip irrigation circuit (DIC) designs;1) one manifold for lateral lines or closed circuits with one manifold of drip irrigation system (CM1DIS);2) closed circuits with two manifolds for lateral lines (CM2DIS), and 3) traditional drip irrigation system (TDIS) as a control. The aims of the work were to study the effect of drip irrigation circuits (DIC) and lateral lines lengths (LLL;where): (LLL1 = 40 m, LLL2 = 60 m, and LLL3 = 80 m) on pressure head (PH) and friction loss (FL). Regarding to LLL and according to PH values, DIC designs could be ranked in the following ascending order: TDIS 1DIS 2DIS. The differences in PH among DIC designs were significant at the 1% level. The depressive effects of LLL on PH could be ranked in the following ascending order: LLL1 2 ≤ LLL3. Differences in PH among LLL treatments were significant at the 1% level except that between LLL2 and LLL3. The effects of interactions among: DIC × LLL on PH were significant at the 1% level with some exceptions. The highest value of PH (9.5 m) and the lowest one (6.05 m) were achieved in the interactions of CM2DIS × LLL1 and TDIS × LLL3, respectively. The shapes of the energy gradient lines were affected by DIC and LLL treatments used through their effect on ?H/H ratio. However, they followed similar trends. According to the FL values, DIC and LLL treatments could be ranked in the following descending orders TDIS > CM1DIS > CM2DIS and LLL1 > LLL2 > LLL3. The differences in FL among DIC and LLL were significant and the effects of interactions among DIC × LLL on FL were significant at the 1% level. The maxim

关键词： Drip Irrigation Circuit Laterals Pressure Friction

Dam Safety in Jordan: Factors Affecting Dam Safety, Responsibilities and Required Actions

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Engineering（科研） 2023年第9期15卷 514-532页

作者： Elias Salamah tayel El-Hasan Maher Abu-Jamah Department of Applied Geology University of Jordan Amman Jordan Department of Chemistry Mutah University Al-Karak Jordan Dams Directorate Jordan Valley Authority Amman Jordan

Dams in Jordan are exposed to a variety of natural and manmade threats like dams worldwide, but with some peculiar threats due to Jordan’s semi-arid climate, steep topography, tectonic activity, especially along the Jordan Rift Valley, position in the turbulent Middle East area, and weak socio-economic situation. In this study, the threats facing the main dams in Jordan are discussed and their sources are defined. The responsible agencies for reducing the threats and eliminating their sources are identified, as long as they are manmade. Natural threats are dealt with as superimposed and Jordan has to adapt to them by taking the necessary protective measures. The study concludes that all dams in Jordan are threatened by climate change and siltation and hence reduction in storage. The quality of stored water in dams, which are used for supplying drinking water such as Al-Wehdah, Wadi Al-Arab, Ziglab, Al-Wala and to a certain extent Al-Mujib is threatened by pollution due to urbanization, agricultural and industrial activities. All dams in Jordan are exposed to sabotage threats, which may negatively affect dams’ water quantities and quality. The stability of dams due to engineering failures is observed in the cases of Al-Kafrain, the left abutment of Al-Mujib, the spillway of Wheidi and eventually Al-Wala Dam. The latter was raised based on unique construction technology. The study recommends developing and implementing, as soon as possible, rigorous action plans to eliminate or, minimize the impacts of threats facing dams in Jordan.

关键词： Dams Jordan Siltation Flood Water Stability Climate Change

Pencil Beam Grid Antenna Array for Hyperthermia Breast Cancer Treatment System

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Circuits and Systems 2017年第5期8卷 122-133页

作者： Mazhar tayel Tamer Abouelnaga Azza Elnagar Electrical Engineering Alexandria University Alexandria Egypt Microstrip Circuits Department Electronics Research Institute (ERI) Giza Egypt Communication and Electronics Engineering Department HIET Kafr El-Shiekh Egypt

In this paper, efficient, high gain and pencil beam grid antenna array is proposed for hyperthermia breast cancer therapy system. The proposed antenna bandwidth extends from 4.8 GHz to 4.9 GHz at resonant frequency of 4.86 GHz. This frequency band has been reported for the breast cancer hyperthermia therapy. The grid long and short sides are responsible for the undesired cross-polarized radiation and desired copolarized radiation, respectively. The unsuitability of the conventional grid antenna array is ensured by investigating its radiation properties. The proposed grid antenna array short side width is varied and its long side width is kept wide as possible to enhance the radiation properties and to reduce the losses. Also, a reflector has been used for gain enhancement purpose. The proposed grid antenna array achieves side lobe level and 3 dB beam width of —27.9 dB and 25.9° for the E-plane and —27.9 dB and 26.3° for the H-plane, respectively. The breast phantom is irradiated by both proposed and conventional grid antenna arrays for 10 minutes. The proposed grid antenna array achieves 8°C temperature increase within the breast phantom area compared to 2°C temperature increase for conventional one. The proposed grid antenna array is highly efficient, high gain and light weight, and it has a very suitable radiation property for hyperthermia breast cancer therapy.

关键词： Breast Cancer Hyperthermia Grid Antenna Array Pencil Beam

Effect of drip irrigation circuits design and lateral line length on: II-flow velocity and velocity head

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Agricultural Sciences 2012年第4期3卷 531-537页

作者： Mohamed tayel David Lightfoot Hani Mansour Southern Illinois University Carbondale Carbondale USA WRFI Department National Research Center (NRC) Giza Egypt

The objectives of the work were to study the effect of drip irrigation circuits (DIC) and lateral lines lengths (LLL) on: Flow velocity (FV) and velocity head (VH). Laboratory tests were conducted at Irrigation Devices and Equipments Tests Laboratory, Agricultural Engineering Research Institute, Agriculture Research Center, Giza, Egypt. The experimental design of laboratory experiments was split in randomized complete block design with three replicates. Laboratory tests carried out on three irrigation lateral lines 40, 60, 80 m (LLL1, LLL2;LLL3) under the following three drip irrigation circuits (DIC): a) one manifold for lateral lines or closed circuits with one manifold of drip irrigation system (CM1DIS);b) closed circuits with two manifolds for lateral lines (CM2DIS), and c) traditional drip irrigation system (TDIS) as a control. Concerning FV values, DIC and LLL treatments could state in the following ascending orders: TDIS 1DIS 2DIS and LLL1 2 3, respectively. FV varied from 0.593 m·sec–1 to 1.376 m?sec–1. i.e FV –1 and this is necessary to avoid the effect of water hammer in the main and sub-main lines, but in lateral line, it can cause silt and clay precipitation problems. The differences in FV among DIC and LLL were significant at the 1% level. The effect of interaction: DIC X LLL on FV values, were significant at the 1% level. The maximum and minimum values of FV were noticed in these interactions: CM2DIS X LLL3 and TDIS X LLL1, respectively. The following ascending orders TDIS 1DIS 2DIS and LLL1 2 3 expressed their effects on VH respectively. Differences in VH among DIC and/or LLL were significant at the 1% with few exceptions. The effects of interactions: DIC X LLL on VH were significant at the 1% level in some cases. The maximum and minimum values of VH were found in the interactions: CM2DIS X LLL3 and TDIS X LLL1, respectively.

关键词： Drip Irrigation Circuit Laterals Flow Head Velocity

Tobacco use among population sub-groups: A gender analysis

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Open Journal of Preventive Medicine 2012年第4期2卷 468-477页

作者： Ahmed Mandil Sahar Abdel Maqsoud Kholoud tayel Mona Shama Epidemiology Department High Institute of Public Health [HIPH] Alexandria University Alexandria Egypt Family Health Department High Institute of Public Health University of Alexandria Alexandria Egypt Health Education Department High Institute of Public Health University of Alexandria Alexandria Egypt Preventive Affairs Department Alexandria University Students’ Clinic and Hospital Alexandria Egypt

Women comprise 20% of world’s billion smokers. Especially troubling is raising prevalence of tobacco use among girls. In fact, it is expected that 20% of women in developing/developed countries will be smokers by 2025. This study analytically compares knowledge, attitudes, and practices of tobacco use, by gender, among 4 sub-populations in Alexandria, Egypt. Methods: A cross sectional approach was used for 4 subgroups (high school students, university students, shopping malls/clubs’ attendees, employees of health-related facilities), 1000 each (total sample size = 4000). A modified version of WHO questionnaire was used for data collection. Results: Smoking prevalence was generally higher among males (29%-44%) compared to females (2% - 9%) in the studied groups. Cafeterias were preferable smoking places for both genders, especially among high school/university students. Most smokers in the 4 subgroups reported that most or all their friends were smokers. Mean knowledge scores were found to be higher among male employees/high school students, compared to females in the same sub-groups. Mean attitude scores towards smoking were higher among females (i.e. against smoking) in the 4 sub-samples. Conclusion & Recommendations: Tobacco use among males is generally higher among males, but females seem to be catching up. Social gatherings seem to attract many youngsters, of both genders, to smoke in public, especially waterpipe (which is a growing epidemic of tobacco use in our communities). Mass community- and gender-based health awareness campaigns are needed, using different channels, including school-based health education interventions, at the earliest age possible.

关键词： Tobacco Use Gender Analysis Population Sub-Groups

Effect of closed circuits drip irrigation system and lateral lines length on growth, yield, quality and water use efficiency of soybean crop

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Agricultural Sciences 2013年第2期4卷 85-90页

作者： Mohamed Yousif tayel Hani Abdel-Ghani Mansour Sabreen Khalil Pibars Water Relation and Field Irrigation Department National Research Center Giza Egypt

Field experiment was conducted for one growing season (2012) in clay loam soil at the Experimental Farm of Faculty of Agriculture, Southern Illinois University at Carbondale (SIUC), USA on soybean crop to study the effect of: 1) the closed drip irrigation system: closed circuits with one and two a manifolds for lateral lines (CM1DIS;CM2DIS) and traditional drip irrigation system (TDIS) as a control;and 2) lateral lines length (LLL): LLL1, LLL2 and LLL3 (40, 60,80 m) on soybean growth, yield, oil, protein content and water use efficiency. Plants were drip irrigated every 4 days. N, K2O and P2O5 fertilizers were added via irrigation water. Data obtained could be outlined as follows: 1) According to the mean values of soybean crop growth (leaf area;plant height), yield (grain and straw), both oil and protein content and water use efficiency, the treatment used could be ranked in the following ascending orders: TDIS < CM1DIS < CM2DIS and LLL3 < LLL2 < LLL1;2) Differences in the means of the studied data among treatments used were significant at the 1% level;3) The effects of the DIC × LLL on the data obtained were significant at the 1 % level;And 4) the highest values of the obtained data and the lowest ones were achieved in the following interactions: CM2DIS × LLL1;TDIS × LLL3, respectively.

关键词： Closed Circuits Drip Irrigation Lateral Lines Soybean WUE