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Common Fixed Point Theorems in Intuitionistic Fuzzy metric Spaces

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模糊系统与数学 2008年第2期22卷 100-106页

作者： h. m. abu-donia A. A. Nasef Department of mathematics Faculty of ScienceZagazig UniversityZagazig Egypt Department of mathematics Faculty of EducationSuezCanal UniversityEl-ArishEgypt

The purpose of this paper is to introduce some types of compatibility of maps, and we prove some common fixed point theorems for mappings satisfying some conditions on intuitionistic fuzzy metric spaces which defined ... 详细信息

关键词：计算方法模糊系统相容性不动点

Prediction of moment of inertia of rotating nuclei

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Chinese Physics C 2020年第11期44卷 179-188页

作者： mohd Kh.m.abu El Sheikh A.A.Okhunov h.abu Kassim m.U.Khandaker Department of Physics University of Malaya50603 Kuala LumpurMalaysia Department of Science in Engineering International Islamic University Malaya50728 Kuala LumpurMalaysia Namangan Institute of Engineering and Technology 160000 NamanganUzbekistan Centre for Biomedical Physics School of Healthcare and Medical SciencesSunway University47500 Bandar SunwayMalaysia

In this study,the mathematical expression formulated by Bohr for the moment of inertia of even-even nuclei based on the hydrodynamical model is *** modification pertains to the kinetic energy of the surface oscillations,including the second and third terms of the R-expansion as well as the first term,which had already been modified by ***,this work can be considered a continuation and support of Bohr's hydrodynamic *** procedure yields a Bohr formula to be multiplied by a factor that depends on the deformation ***'s(modified)formula is examined by applying it on axially symmetric even-even nuclei with atomic masses ranging between 150 and 190 as well as on some triaxial symmetry *** this paper,the modification of Bohr's formula is discussed,including information about the stability of this modification and the second and third terms of the R-expansion in Bohr's *** results of the calculation are compared with the experimental data and Bohr's results recorded *** results obtained are in good agreement with experimental data,with a ratio of approximately 0.7,and are better than those of the unmodified ones.

关键词： moment of inertia hydrodynamical model irrotational motion

InGaN/GaN laser diode characterization and quantum well number effect

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Chinese Optics Letters 2009年第3期7卷 226-230页

作者： S.m.Thahab h.abu hassan Z.hassan Nano-Optoelectronics Research and Technology Laboratory School of PhysicsUniversiti Sains Malaysia

The effect of quantum well number on the quantum efficiency and temperature characteristics of In- GaN/GaN laser diodes （LDs） is determined and investigated. The 3-nm-thick In0.13Ca0.87N wells and two 6-am-thick GaN barriers are selected as an active region for Fabry-Perot （FP） cavity waveguide edge emitting LD. The internal quantum efficiency and internal optical loss coefficient are extracted through the simulation software for single, double, and triple InGaN/GaN quantum wells. The effects of device temperature on the laser threshold current, external differential quantum efficiency （DQE）, and output wavelength are also investigated. The external quantum efficiency and characteristic temperature are improved significantly when the quantum well number is two. It is indicated that the laser structures with many quantum wells will suffer from the inhomogeneity of the carrier density within the quantum well itself which affects the LD performance.

关键词： Computer software Efficiency Fabry Perot interferometers Quantum well lasers Semiconductor lasers Semiconductor quantum wells

Survey and Analysis of VoIP Frame Aggregation methods over A-mSDU IEEE 802.11n Wireless Networks

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Computers, materials & Continua 2021年第2期66卷 1283-1300页

作者： mosleh.m.abualhaj Abdelrahman h.hussein manjur Kolhar mwaffaq abu Alhija Al-Ahliyya Amman University AmmanJordan Prince Sattam Bin Abdulaziz University Al-KharjSaudi Arabi

The IEEE 802.11n standard has provided prominent features that greatly contribute to ubiquitous wireless *** the last ten years,voice over IP(VoIP)has become widespread around the globe owing to its low-cost or even free call *** combination of these technologies(VoIP and wireless)has become desirable and inevitable for ***,VoIP faces a bandwidth utilization issue when working with 802.11 wireless *** bandwidth utilization is inefficient on the grounds that(i)80 bytes of 802.11/RTP/UDP/IP header is appended to 10–730 bytes of VoIP payload and(ii)765μs waiting intervals follow each 802.11 VoIP *** considering the quality requirements of a VoIP call,be including frame aggregation in the IEEE 802.11n standard has been suggested as a solution for the bandwidth utilization ***,several aggregation methods have been proposed to handle the quality requirements of VoIP calls when carried over an IEEE 802.11n wireless *** this survey,we analyze the existing aggregation methods of VoIP over the A-mSDU IEEE 802.11n wireless *** survey provides researchers with a detailed analysis of the bandwidth utilization issue concerning the A-mSDU 802.11n standard,discussion of the main approaches of frame aggregation methods and existing aggregation methods,elaboration of the impact of frame aggregation methods on network performance and VoIP call quality,and suggestion of new areas to be investigated in conjunction with frame *** survey contributes by offering guidelines to design an appropriate,reliable,and robust aggregation method of VoIP over 802.11n standard.

关键词： VoIP VoIP frame aggregation IEEE 802.11n bandwidth utilization A-mSDU A-mPDU

Synthesis of Dy_2O_3 nanoparticles via hydroxide precipitation: effect of calcination temperature

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Journal of Rare Earths 2014年第3期32卷 259-264页

作者： Bahaa m.abu-Zied Abdullah m.Asiri Chemistry Department Faculty of Science King Abdulaziz University Center of Excellence for Advanced materials Research (CEAmR) King Abdulaziz University Chemistry Department Faculty of Science Assiut University

This work described the preparation of dysprosium oxide, Dy203, nanoparticles using the homogeneous precipitation method. Dy3＋ ions were precipitated using NaOh solution. The obtained product was filtered, dried, and then calcined for 1 h at the temperature range of 300-700 ℃ in static air. The calcination temperature of the Dy-precttrsor was chosen based on its decomposi- tion as indicated by the TGA analysis. The crystalline structure and surface morphology of the calcined solids were studied by X-ray diffraction （XRD）, field emission scanning electron microscopy （FE-SEm）, transmission electron microscopy （TEm） and X-ray pho- toelectron spectroscopy （XPS）. The obtained results revealed that Dy203 with crystallites size of 11-21 nm was formed at 500 ℃. Such value increased to 25-37 nm for the sample calcined at 700 ℃.

关键词： nanocrystalline dysprosium oxide Dy203 precipitation method Dy203 nanoparticles rare earths

malaria prevalence in north-eastern Nigeria:A cross-sectional study houben Ch^(1*),Fleischmann h^2,Gǜckel m^3

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Asian Pacific Journal of Tropical medicine 2013年第11期6卷 865-868页

作者： houben Ch Fleischmann h Gckel m Diagnostic Center mmm group & Specialist hospital Yola Hospital RoadP.M.B.2266YolaAdamawa.StateNigeria medical mission Institute Tropical MedicineHermann Schell Str 797074 WrzburgGermany helios Kliniken Schwerin Wismarsche Str 393-39719049 SchwerinGermany

Objective:To assess the prevalence of malaria parasitemia in north-east Nigeria and to evaluate the measures for the prevention of ***:A village in north-eastern Nigeria was selected for the cross sectional study at the height of the rainy season in October 2011.A total of 550 inhabitants of a hamlet were recruited for this *** obtaining the consent individuals received a structured interview and were tested for malaria parasites in their blood *** testing positive for malaria were given a course of artemesinin-based combination therapy（ACT）.Results:A total of 497 inhabitants representing approximately 90 percent of the population participated:a quarter of the study group carried malaria parasitesexclusively Plasmodium falciparum（***）-representing a *** parasite rate（PfPR） of 24.5%.Besides,53/138 in the age group of 2 to hildren tested positive for *** representing a PfPR2-10 value of 38.4%.malaria control measures were used in just under a third（157/497） of this *** these measures 28/157（17.8%） still tested positive for ***:The malaria burden is overestimated for this region in north-east *** findings support an intermediate pattern of malaria *** 30%bed nets coverage for malaria control is well below the WhO estimates for 2011.

关键词： malaria control malaria endemicity malaria prevalence malaria transmission

Processing of Landsat 8 Imagery and Ground Gamma-Ray Spectrometry for Geologic mapping and Dose-Rate Assessment, Wadi Diit along the Red Sea Coast, Egypt

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Open Journal of Geology 2016年第8期6卷 911-930页

作者： Ahmed E. Abdel Gawad Atef m. abu donia mahmoud Elsaid Nuclear materials Authority Cairo Egypt

maximum Likelihood (mLh) supervised classification of atmospherically corrected Landsat 8 imagery was applied successfully for delineating main geologic units with a good accuracy (about 90%) according to reliable ground truth areas, which reflected the ability of remote sensing data in mapping poorly-accessed and remote regions such as playa (Sabkha) environs, subdued topography and sand dunes. Ground gamma-ray spectrometric survey was to delineate radioactive anomalies within Quaternary sediments at Wadi Diit. The mean absorbed dose rate (D), annual effective dose equivalent (AEDE) and external hazard index (hex) were found to be within the average worldwide ranges. Therefore, Wadi Diit environment is said to be radiological hazard safe except at the black-sand lens whose absorbed dose rate of 100.77 nGy/h exceeds the world average. So, the inhabitants will receive a relatively high radioactive dose generated mainly by monazite and zircon minerals from black-sand lens.

关键词： Landsat 8 Imagery Image Processing maximum Likelihood Classification Environmental monitoring Absorbed Dose Rate hazard Index

A study of the operating parameters and barrier thickness of Al_(0.08)In_(0.08)Ga_(0.84)N/Al_xIn_yGa_(1-x-y)N double quantum well laser diodes

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Science China(Technological Sciences) 2011年第1期54卷 47-51页

作者： A.J.GhAZAI S.m.ThAhAB h.abu hASSAN Z.hASSAN Nano-Optoelectronics Research and Technology Laboratory School of PhysicsUniversiti Sains Malaysia material Engineering Department College of EngineeringUniversity of Kufa

The operating parameters such as the internal quantum efficiency （η）, internal loss （α） and transparent threshold current density （J0） of double quantum well laser diodes were investigated and identified using the program, Integrated System Engineering-Technical Computer Aided Design （ISE-TCAD）. Various thicknesses （6, 7, 8, 10, 12 rim） of AlxInyGa1-x-yN barriers with （3 nm） Al0.08In0.08Ga0.84N wells as an active region were studied. The lowest threshold current （lth）, and the highest output power （Pop） were 116 mA and 196 mW respectively, at barriers thickness of 6 nm, Al mole fraction of 10% and In mole fraction of 1%, at an emission wavelength of 359.6 nm.

关键词： AIInGaN quaternary UV laser diode quantum well barrier thickness

Fabrication,characterization,and electrical conductivity properties of Pr_6O_(11) nanoparticles

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Journal of Rare Earths 2013年第7期31卷 701-708页

作者： Bahaa m.abu-Zied Youssef A.mohamed Abdullah m.Asiri Chemistry Department Faculty of ScienceKing Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia Chemistry Department Faculty of ScienceAssiut University71516 AssiutEgypt Center of Excellence for Advanced materials Research(CEAmR) King Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia

PrrOll nanoparticles were obtained by subsequent thermal decomposition of the as-prepared precipitate formed under ambient temperature and pressure using NaOh as precipitant. The calcination process was affected, for 1 h in static air atmosphere, at 400-700 ℃ temperature range. The different samples were characterized using X-ray diffraction （XRD）, transmission electron microscopy （TEm）, field emission scanning electron microscopy （FE-SEm）, thermogravimetric analysis （TGA）, in situ electrical conductivity, and N2 adsorption/desorption. The obtained results demonstrated that nano-crystalline Pr6O11, with crystallites size of 6-12 nm, started to form at 500 ℃. Such value increased to 20-33 nm for the sample calcined at 700℃. The as-synthesized PrrOll nanoparticles presented high electrical conductivity due to electron hopping between Pr（III）-Pr（IV） pairs.

关键词： nanocrystalline praseodymium oxide Pr6O11 nano structured materials electrical conductivity rare earths