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A Novel Methodology to Design Miniaturized Regular Planar Inverted-F Antennas Based on Parametric Simulations

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Journal of Electromagnetic Analysis and Applications 2013年第7期5卷 302-311页

作者： Abdelhakim Elouadih ahmed Oulad-Said moha Mrabet Hassani Department of Electrical and Telecommunications Engineering Royal Air Academy (ERA) Marrakesh Morocco Department of Physics Semlalia University of Sciences (FSSM) Marrakesh Morocco

This paper describes a novel methodology to design PIFA (Planar Inverted-F Antenna) antennas based on parametric simulations. The parameters considered in the parametric design are ground plan dimensions, height of radiating plate, feeding point position, shorting plate width and position. The choice of the parameters that must be varied independently or simultanously is important to design optimized antenna. The author studied two scenarios in precedent works [1,2]. He exposes here a third scenario of varing antenna parameters to design and simulate by HFSS (High Frequency Simulator Structure) simulator a probe-fed dual band PIFA for the use in GSM 850 band (824 MHz - 894 MHz) and PCS 1900 band (1850 MHz - 1990 MHz). The author compares the three scenarios and establishes a novel methodology to design optimized and miniaturized antennas mounted on mobile handsets.

关键词： PIFA HFSS Design Methodology

Design and Simulation by HFSS of a Slim UWB PIFA Antenna

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World Journal of Engineering and Technology 2013年第2期1卷 17-22页

作者： Abdelhakim Elouadih ahmed Oulad-Said moha Mrabet Hassani Department of Electrical and Telecommu- nications Engineering Royal Air Academy (ERA) Marrakesh Morocco Department of Physics Semlalia University of Sciences (FSSM) Marrakesh Morocco

This paper describes the design and simulation by High Frequency Structure Simulator (HFSS) of a probe-fed Planar Inverted-F Antenna (PIFA) for the Ultra Wide Band (UWB) personal area networks. The slim antenna presents a height of 2 mm and a bandwidth of more than 766 MHz. This bandwidth was improved by etching a U-slot in the antenna patch. The bandwidth offered then by the antenna is 839 MHz around the resonant frequency of 9 GHz. The improvement of bandwidth was accompanied by decreasing in gain and radiation efficiency. The simulation allowed the characterization of the designed antenna and the computing of different antenna parameters like S11 parameter, resonant frequency, bandwidth, radiation efficiency, gain and diagram pattern. The results are very interesting and respect the Federal Communications Commission (FCC) requirements.

关键词： PIFA HFSS UWB

Design and Parametric Simulation of a Miniaturized PIFA Antenna for the PCS Band

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Wireless Engineering and Technology 2013年第2期4卷 105-111页

This paper describes the design and simulation by HFSS simulator of a probe-fed Planar Inverted-F Antenna (PIFA) for the use in PCS band [1850 MHz - 1990 MHz]. A methodology based on parametric simulations (parameters are ground plan dimensions, height of radiating plate, feeding point position, shorting plate dimensions and positioning) was used to design optimized antenna. The simulation allowed the characterization of the designed antenna and the computing of different antenna parameters like S11 parameter, resonant frequency, SWR, bandwidth impedance in feeding point, gain, 2D and 3D diagram pattern, Fields distribution. The simulation results are interesting and respect the mean PCS requirements.

关键词： PCS HFSS PIFA Patch Antenna Parametric Simulation

Design and Parametric Simulation of a Bi-Band Miniaturized PIFA Antenna for the GSM900 and DCS1800 Bands

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Journal of Electromagnetic Analysis and Applications 2013年第5期5卷 189-195页

作者： Abdelhakim Elouadih ahmed Oulad-Said moha Mrabet Hassani Department of Electrical and Telecommunications Engineering Royal Air Academy (ERA) Marrakesh Morocco Department of Electrical and Telecommunications Engineering Royal Air Academy (ERA) Marrakesh Morocco Department of Physics Semlalia University of Sciences (FSSM) Marrakesh Morocco.

This paper describes the design and simulation by HFSS simulator of a probe-fed Planar Inverted-F Antenna (PIFA) for the use in GSM900 band [890 MHz - 960 MHz] and DCS1800 band [1710 MHz - 1880 MHz]. A methodology based on parametric simulations (parameters are ground plan lenght, height of radiating plate, feeding point position, shorting plate width and position) was used to design optimized antenna. The simulation allowed the characterization of the designed antenna and the computing of different antenna parameters like S11 parameter, resonant frequency, VSWR, bandwidth, impedance in feeding point, gain, diagram pattern and Fields distribution. The results were very interesting and respect the GSM requirements.

关键词： GSM DCS HFSS PIFA Patch Antenna Parametric Simulation

Design and Simulation of a PIFA Antenna for the Use in 4G Mobile Telecommunications Networks

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International Journal of Communications, Network and System Sciences 2013年第7期6卷 325-332页

作者： Abdelhakim Elouadih ahmed Oulad-Said moha Mrabet Hassani Department of Physics Semlalia University of Sciences (FSSM) Marrakesh Morocco

This paper describes the design and simulation by HFSS simulator of a probe-fed and multi-band Planar Inverted-F Antenna (PIFA) for the 4G mobile networks. The antenna works in 8 bands. Five bands are auctioned by FCC for 4G (LTE and WiMax) such 710 MHz, 1900 MHz (PCS), 2.3 GHz (WCS band), 3.65 GHz (rural 4G) and 5.8 GHz (FCC unlicensed band). The antenna allows working around 910 MHz ISM band. The GPS signal can be received in GPS L2 band around the frequency 1575 MHz. The antenna offers also a wideband around 8.62 GHz. The simulation allowed the characterization of the designed antenna and the computing of different antenna parameters like S11 parameters, resonant frequency, bandwidth, radiation efficiency, gain and diagram pattern. The results are very interesting and respect mostly the requirements.

关键词： PIFA HFSS 4G ISM GPS

Impact of the association between elevated oestradiol and low testosterone levels on erectile dysfunction severity

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Asian Journal of Andrology 2013年第4期15卷 492-496,I0007-I0008页

作者： ahmed I E1-Sakka Department of Urology Suez Canal University 41111 Ismailia Egypt and AI-Noor Specialist Hospital Makkah PO Box 6251 Saudi Arabia

Our aim was to assess the impact of the association between elevated oestradiol （E2） and low testosterone （T） levels on erectile dysfunction （ed） severity. A total of 614 male patients with ed and a normal or low T level in association with normal or elevated E2 levels were enrolled. Patients underwent routine laboratory investigations in addition to measurements of total T, total E2, follicle-stimulating hormone （FSH）, luteinizing hormone （LH） and prolactin. We compared the responses to the erectile function domain, Q3 （achieving erection） and Q4 （maintaining erection） of the International Index for Erectile Function （IIEF） score in patients with the following： normal T and E2 levels; low T level; low T level and elevated E2 level; and elevated E2 level. Of the patients included, 449 （73.1%） had normal T and E2 levels, 110 （17.9%） had a low T level, 36 （5.9%） had a low T level and an elevated E2 level, and 19 （3.1%） had an elevated E2 level. Increased ed severity was significantly associated with low T levels, elevated E2 levels, and both a low T level and an elevated E2 level. Additionally, the mean values of the EF-domain, Q3 and Q4 were significantly lower in patients with both a low T level and an elevated E2 level compared to patients with any condition alone. In conclusion, a low T level had the primary effect on erectile function; however, a concomitantly elevated E2 level had an additive impairment effect.

关键词： erectile dysfunction (ed) hypogonadism testosterone oestradiol

Synthesis and study the influence of yttrium doping on band structure,optical,non-linear optical and dielectric results for Ca_(12)Al_(14)O_(33) (C12A7) single crystals grown using traveling-solvent floating zone (TSFZ) method

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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

Effects of Plasticizers,Antioxidants and Burning Rate Modifiers on Aging Performance of the HTPB/HMDI Composite Solid Propellant

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含能材料 2019年第1期27卷 21-27,90页

作者： ahmed M Enew Ehab Abadir Sahar Elmarsafy Karim K Elsharkawy Chemical Department Faculty of EngineeringCairo University School of Chemistry and Environment Beijing University of Aeronautics and Astronautics

The effects of plasticizers,antioxidants and burning rate modifiers on the aging performance of the composite solid propellant based on hydroxyl-terminated polybutadiene(HTPB)/hexamethylene diisocyanate(HMDI)were explored by apply-ing an accelerated aging program for 90 day at 70 ℃. The HTPB propellant matrix with the diisooctyl sebacate(DOS)as plasti-cizers and diisooctyl azelate(DOZ), antioxidants as N,N ′-Diphenyl-p-phenylenediamine(AO) and 2,2′-methylenebis(4-methyl-6-tert-butylphenol)(cyanox 2246)and burning rate modifiers as barium ferrite(BF),copper chromites(CC)and fer-ric oxide(FO)were varied. Results show that sample(S1)which based on DOS decreases the stress value and increases the strain value which considered to be an excellent start for aging program. Sample(S3)containing AO presents the higher resis-tance to oxidation showing the better performance that reflects on increasing the shelf life of the composite solid propellant mo-tor. Sample(S5)which based on BF enhances the ballistic performance among over the other tested two samples. The accelerat-ed aging program allowed us to estimate the motor in-service lifetime.

关键词： polybutadiene(HTPB)/hexamethylene diisocyanate(HMDI)composite solid propellant plasticizers antioxidants burning rate modifiers aging program

Sepsis patient evaluation emergency department (SPEed) score & mortality in emergency department sepsis (MedS) score in predicting 28-day mortality of emergency sepsis patients

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Chinese Journal of Traumatology 2019年第6期22卷 316-322页

作者： Adel Hamed Elbaih Zaynab mohammed Elsayed Rasha Mahmoud ahmed Sara ahmed Abd-elwahed Department of Emergency Medicine Faculty of MedicineSuez Canal UniversityIsmailiaEgypt Department of Emergency Medicine Sulaiman Al-Rajhi CollegesFaculty of MedicineSaudi Arabia

Purpose:Sepsis is a common acute life-threatening condition that emergency physicians routinely *** options within the Emergency Department(ed)are limited due to lack of infrastructure,consequently limiting the use of invasive hemodynamic monitoring or imaging *** mortality rate due to sepsis can be assessed via multiple scoring systems,for example,mortality in emergency department sepsis(MedS)score and sepsis patient evaluation in the emergency department(SPEed)score,both of which quantify the variation of mortality rates according to clinical findings,laboratory data,or therapeutic *** study aims to improve the management processes of sepsis patients by comparing SPEed score and MedS score for predicting the 28-day mortality in cases of emergency ***:The study is a cross-sectional,prospective study including 61 sepsis patients in ed in Suez Canal University Hospital,Egypt,from August 2017 to June *** were selected by two steps:(1)suspected septic patients presenting with at least one of the following abnormal clinical findings:(a)body temperature higher than 38℃ or lower than 36℃,(b)heart rate higher than 90 beats/min,(c)hyperventilation evidenced by respiratory rate higher than 20 breaths/min or PaCO2 lower than 32 mmHg,and(d)white blood cell count higher than 12,000/μL or lower than 4000/μL;(2)confirmed septic patients with at least a 2-point increase from the baseline total sequential organ failure assessment(SOFA)score following *** inclusion criteria included adult patients with an age≥18 years regardless of gender and those who had either systemic inflammatory response syndrome or suspected/confirmed *** were shortly follow-up for the 28-day *** patient was subject to SPEed score and MedS score and then the results were compared to detect which of them was more effective in predicting *** receiver operating characteristic curves were also done for MedS and SPE

关键词： Sepsis Sepsis patient evaluation emergency department score Mortality in emergency department sepsis score Mortality