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Secrecy Outage Probability Analysis Based on Cognitive Decode-and-Forward Relaying

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Computers, materials & Continua 2020年第3期62卷 1387-1395页

作者： Ruoyu Su Xiaojun Sun Fei Ding Dengyin Zhang Hongbo Zhu m.i.m.wahab Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Tele-CommunicationsNanjing210003China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Ministry of EducationNanjing University of Posts and TelecommunicationsNanjing210003China School of information Science and Engineering Southeast UniversityNanjing210018China Department of Electrical and Computer Engineering Faculty of Engineering and Applied ScienceMemorial University of NewfoundlandSt.John’sA1B 3X5Canada Department of mechanical and industrial Engineering Ryerson UniversityToronto M5B 2K3Canada

Wireless communications have to face to several different security issues in practice due to the nature of *** information theory is well known to provide efficient approaches to address security issues in wireless communications,which attracts much attention in both industry and academia in recent *** this paper,inspired by information theory,we study the outage probability of the opportunistic relay selection based on cognitive decode-and-forward relaying with the secrecy ***,the closed-form expression of the outage probability is ***,the asymptotic performance evaluation on the basis of the analytical results is *** simulation results show that the relay selection can reduce the outage probability in accordance with our theoretical analysis.

关键词： Secure communication average secrecy rate relay selection probability density function

The role of oil futures intraday information on predicting US stock market volatility

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Journal of management Science and Engineering 2021年第1期6卷 64-74页

作者： Yusui Tang Xiao Xiao m.i.m.wahab Feng ma School of Economics&management Southwest Jiaotong UniversityChengduChina Department of mechanical and industrial Engineering Ryerson UniversityTorontoCanada

This study investigates the role of oil futures price information on forecasting the US stock market volatility using the HAR ***-sample results indicate that oil futures intraday information is helpful to increase the ***,compared to the benchmark model,the proposed models improve their predictive ability with the help of oil futures realized *** particular,the multivariate HAR model outperforms the univariate ***,considering the contemporaneous connection is useful to predict the US stock market ***,these findings are consistent across a variety of robust checks.

关键词： Volatility forecasting The US stock market Oil market volatility Realized volatility DCC model

Corrosion Behaviour of Nickel in Chloroacetic Acids and its inhibition

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Journal of materials Science & Technology 2004年第1期20卷 121-125页

作者： S.m.Rashwan A.Emam S.m.Abd El-wahab m.m.mohamed Chemistry Department Faculty of Science Suez Canal University Ismailia EgyptChemistry Department Faculty of Science Suez Canal University Ismailia EgyptChemistry Department Faculty of Science Ain Shams University Cairo EgyptChemistry Department Faculty of Science Suez Canal University Ismailia Egypt

Anodic dissolution behaviour of Ni in mono-, di- and trichloroacetic acids has been investigated by measuring current densities of Ni electrode (versus SCE) at different potentials. Effects of acid concentration, pH, scan rate and additive inhibitor on the potential were studied and they revealed that there is a considerable shift of potential. Potentiodynamic polarization measurements show that the corrosion rate of Ni in chloroacetic acid solutions increases by increasing the previous factors. However, by adding inhibitor, it decreases.

关键词： Corrosion Nickel Chloroacetic acids inhibition

Radionuclides measurements and mineralogical studies on beach sands, East Rosetta Estuary, Egypt

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Chinese Journal Of Geochemistry 2013年第2期32卷 146-156页

作者： Abd El wahab m. El Nahas H.A. Physics Department Faculty of Women for Arts Science and Education Ain Shams University Cairo P.O 11757 Egypt Nuclear materials Authority Cairo P.O. Box 530 Egypt

Radiometric measurements were carried out for the beach sands from East Rosetta estuary to determine the activity concentrations of 238 U, 226 Ra, 232 Th, and 40 K, using a Hyper Pure Germanium spectrometer, to estimate the dose rates and radiation hazard indices. The average specific activities are 778.20 Bq/kg for 238 U; 646.89 Bq/kg for 226 Ra; 621.92 and 627.85 Bq/kg for the 222 Rn daughters 214 Pb and 214 Bi respectively. The average specific activity of 232 Th is 1510.25 Bq/kg, while the calculated specific activity for 40 K has an average of 8.41 Bq/kg. The average specific activity of 235 U is 38.61 Bq/kg. The average absorbed dose rate is 1211.36 nGy/h, 20 times higher than the estimated average global primordial radiation of 60 nGy/h and 6 times higher than that of the world range (10-200 nGy/h). The radium equivalent (Ra eq ) values are from 6 to 9 times the recommended value. The internal and external hazard indices (H int , H ex ) indicate that their values are from 6 to 11 times the permissible values of these indices. These higher values may be due to the presence of economic heavy minerals containing radionuclides as zircon and monazite as well as some trace minerals, thorite and uranothorite. The mineralogical study indicates the beach sands contain heavy minerals, zircon, monazite, rutile, ilmenite, leucoxene, magnetite and garnet. The average abundance of zircon is 0.175 wt% ranging from 0.125 wt% to 0.239 wt%, while it is 0.004wt% ranging from 0.001 wt% to 0.007 wt% for monazite. The average abundance is 0.087 wt% for rutile; 2.029 wt% for ilmenite; 1.084 wt% for magnetite; 0.384 wt% for leucoxene and 0.295 wt% for garnet.

关键词：放射性核素海滩砂矿物学核素测量河口平均丰度埃及辐射测量

Conceptual Design of Glass/Renewable Natural Fibre-Reinforced Polymer Hybrid Composite motorcycle Side Cover

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Journal of Renewable materials 2021年第11期9卷 1973-1989页

作者： m.A.F.A.wahab S.m.Sapuan m.m.Harussani m.Y.m.Zuhri A.A.Saleh Department of mechanical and manufacturing Engineering Universiti Putra MalaysiaSerdang43400Malaysia Laboratory of Biocomposite Technology Institute of Tropical Forestry and Forest Products(INTROP)Universiti Putra MalaysiaSerdang43400Malaysia Department of mechanical andmanufacturing Engineering Faculty of EngineeringUniversiti Malaysia SarawakKota Samarahan94300Malaysia

This paper presents the development process relating to the conceptual design of glass/renewable natural fibrereinforced polymer hybrid composite motorcycle side *** side cover is a component frequently made from plastic or steel that functions on covering the motorcycle parts,components and systems such as frame,battery,electrical systems and mechanical *** Analysis Systems Techniques(FAST)is used to identify the functions of motorcycle side *** right-side cover of motorcycle model SYm E-Bonus 110 has been physically studied to identify the competitive benchmarking *** functions and competitive benchmarking criteria are then compiled and integrated with the environmental requirements to identify the Product Design Specifications(PDS).The coir fibre has been selected from six identified dominant renewable natural fibre used for automotive component through integration of Ranking method and Quality Based Selection(QBS).Then the polypropylene matrix is selected after shortlisting the existing thermoplastic that is used with coir fibre and has high suitability for injection moulding *** polypropylene matrix is then evaluated using Weighted Evaluation matrix(WEm)by comparing to benchmark material which is Acrylonitrile Butadiene Styrene(ABS).After that,the conceptual design development of glass/renewable coir fibre-reinforced polypropylene motorcycle side cover is carried out using an integrated Theory of inventive Problem Solving(TRiZ)and morphological Chart,followed by final conceptual design selection using integration of Pugh Scoring method and *** conceptual design development intended on improving the biodegradability to reduce pollution to the ***,the usage of glass/coir fibre-reinforced polypropylene hybrid composite may increase the weight due to higher *** innovative design concepts have been developed and the selected final concept design has the most minimum number of ribs an

关键词： Renewable natural fibre coir fibre hybrid composite conceptual design PDS TRiZ morphological chart QBS FAST diagram WEm natural fibre selection pugh scoring method

Nano-confined ammonia borane for chemical hydrogen storage

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Frontiers of Chemical Science and Engineering 2012年第1期6卷 27-33页

作者： m. A.wahab Huijun ZHAO X. D. YAO ARC Centre of Excellence for Functional Nanomaterials Australian Institute for Engineering and Nanotechnology the University of Queensland St Lucia 4072 Australia Centre for Clean Energy and Environment Griffith University Gold Coast 4222 Australia Queensland micro-and Nanotechnology Centre Griffith University Nathan 4111 Australia

There is a great demand for a sufficient and sustainable energy supply. Hence, the search for applicable hydrogen storage materials is extremely important owing to the diversified merits of hydrogen energy. in this regard, ammonia borane （NH3BH3, AB） containing 19.6wt-% hydrogen has been considered as a promising material for hydrogen storage applications to realize the ＂hydrogen economy＂, but with limits from slow kinetics of hydrogen release and by-product of trace gases such as ammonia and borazine. in this review, we introduce the recent research on AB, regarding to the nanoconfinement effect on improving the kinetics at a relatively low temperature and the prevention/reduction of undesirable gas formation.

关键词： ammonia borane hydrogen storage

Optical properties and radiative rates of Nd^(3+) doped zinc-sodium phosphate glasses

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Journal of Rare Earths 2019年第3期37卷 253-259页

作者： A.A.El-maaref Shimaa Badr Kh.S.Shaaban E.A.Abdel wahab m.m.ElOkr Physics Department Faculty of Science Al-Azhar University modern Academy for Engineering & Technology Chemistry Department Faculty of Science Al-Azhar University

Preparation using melt quenching technique and optical characterizations of Nd^(3+) doped Zn-Na phosphate glasses are presented. The structure of the present glasses was studied using X-ray diffraction and FT-iR spectroscopy. UV-vis spectra of the present glasses were analyzed at different concentrations of Nd_2 O_3. The effect of neodymium concentration on the density and energy band gap was investigated. The density of the present glasses slightly increases with the increasing of Nd_2 O_3. A small variation of energy band gap with the increasing of neodymium content is observed as well, while E_g values decrease with the increase of Nd_2 O_3 content. The E_g values lie between 4.36 and 4.69 eV. Based on the measured optical spectra, Judd-Ofelt theory was used to determine the optical parameters such as line strengths, optical intensity parameters(Ω_t), transition probabilities, and transition lifetimes. Hypersensitive transitions were identified in the absorption spectrum, the greatest line strengths are recorded at the transitions^2 G_(7/2)+ ~4 G_(5/2), ~4 S_(3/2) + ~4 F_(7/2) and ~4 D_(1/2) + ~4 D_(3/2)+ ~4 D_(5/2) + ~2 i_(11/2) with wavelengths of 580, 475 and 355 nm,respectively. Lifetimes of the important ~4 F_(3/2) laser-level were determined; which show decreasing trend with the increasing of Nd_2 O_3 content and are found to be between 0.838 and 1.595 ms. The uncertainty of the present results was estimated. The RmS deviations were determined, which show lower values than those in the literature.

关键词： Phosphate glass UV-vis spectroscopy Judd-Ofelt Radiative rates Rear earth ions

Numerical simulation of multi-phase combustion flow in solid rocket motors with metalized propellant

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航空动力学报 2009年第7期24卷 1654-1660页

作者： SHAFQAT wahab School of Astronautics Beijing University of Aeronautics and Astronautics

multi-phase flowfield simulation has been performed on solid rocket motor and effect of multi-phases on the performance prediction of the solid rocket motor(SRm) is *** the combustion of aluminized propellant,the aluminum particles in the propellant melt and formliquid aluminum at the burning propellant *** the flow within the rocket motor is multi phase or two phase because it contains droplets and smoke particles of *** mulations have been performed on a large scale motor,to observe the effect of the flowfield onthe chamber and nozzle as *** particles diameters and Rosin-Rammler diameter distribution method that is based on the assumption that an exponential relationship exists betweenthe droplet diameter,dand mass fraction of droplets with diameter greater thandhave been used for the si mulation of different distribution of Al2O3 droplets present in *** sizes in the range of 1-100μm are used,as being the most common *** this approachthe complete range of particle sizes is dividedinto a set of discrete size ranges,eachto be defined by single streamthat is part of the *** scheme-flux differencing splitting based on approxi mate Riemann problem has been used to si mulate the effects of the multi-phase *** is second order upwind scheme in which flux differencing splitting method is *** cater for the turbulence effect,Spalart-All maras model has been *** results obtained show the great sensitivity of this diameters distribution and particles concentrations to the SRmflowdynamics,primarily at the motor chamber and nozzle *** results are shown with various sizes of the particles concentrations and geometrical configurations including models for SRm and *** analysis also provides effect of multi-phase on performance prediction of solid rocket motor.

关键词： solid rocket motor nozzle multiphase flow Rosin-Rammler diameter distribution method Roe FDS (flux differencing splitting) performance prediction

mass spectrometry detection of basic drugs in fast chiral analyses with vancomycin stationary phases

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Journal of Pharmaceutical Analysis 2018年第5期8卷 324-332页

作者： Hongyue Guo m.Farooq wahab Alain Berthod Daniel W.Armstrong Department of Chemistry and Biochemistry University of Texas at Arlington institut des Sciences Analytiques CNRS Université de Lyon 1

Current trends in chiral analysis of pharmaceutical drugs are focused on faster separations and higher separation efficiencies, Core-shell or superficially porous particles （SPP） based chiral stationary phases （CSPs） provide reduced analysis times while maintaining high column efficiencies and sensitivity. in this study, mobile phase conditions suitable for chiral analyses with electrospray ionization LC-mS were systematically investigated using vancomycin as a representative CSP. The performance of a 2.7 μm SPP based vancomycin CSP （SPP-V） 10 cm ×0.21 cm column was compared to that of a corresponding 5 μm fully porous particles based analogue column. The results demonstrated that the SPP-V column provides higher efficiencies, 2-5 time greater sensitivity and shorter analysis time for a set of 22 basic pharma- ceutical drugs. The SPP-V was successfully applied for the analysis of the degradation products of racemic citalopram whose enantiomers could be selectively identified by mS.

关键词： mass spectrometry detection Chiral separation Basic drugs Beta-blockers Superficially porous particle Fully porous particle Fast separation Vancomycin