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Comparison of Methods of Es.i.ating Mis.i.g Valu.s.i. Time series

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Open Jou.nal of statis.i.s 2018年第2期8卷 390-399页

作者： i. s. iwu.ze E. C. Nwogu.V. u. Nlebedim u. i. Nwosu.u. E. Chinyem Department of statis.i.s Federal University of Technology Owerri Nigeria school of Mathematics and statis.i.s University of Sheffield Sheffield UK

This paper proposes new methods of es.i.ating mis.i.g valu.s.i. time series data while comparing them with exis.i.g methods. The new methods are based on the row, colu.n and overall averages of time series data arranged in a Bu.s-Ballot table with m rows and s colu.ns. The methods assu.e that 1) only one valu. is mis.i.g at a time, 2) the trending cu.ve may be linear, qu.dratic or exponential and 3) the decomposition method is either Additive or Mu.tiplicative. The performances of the methods are assessed by comparing accu.acy measu.es (MAE, MAPE and RMsE) compu.ed from the deviations of es.i.ates of the mis.i.g valu.s from the actu.l valu.s u.ed in simu.ation. Resu.ts show that, u.der the stated assu.ptions, es.i.ates from the new method based on fu.l decomposition of a series.i. the best (in terms of the accu.acy measu.es) when compared with other two new and the exis.i.g methods.

关键词： Mis.i.g Valu.s Bu.s-Ballot Table Row and Colu.n Averages Row and Colu.n Variances Trend Parameters and seasonal indices

Combined heat and mass transfer by mixed convection MHD flow along a porou. plate with chemical reaction in presence of heat sou.ce

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Applied Mathematics and Mechanics(English Edition) 2010年第10期31卷 1217-1230页

作者： J.Zu.CO s.ahmed ETs.i.geniería indu.trial Departamento de Ingeniería Térmicay FluidosUniversidad Politécnica de Cartagena Flu.d Dynamics Research Department of MathematicsGoalpara College

An exact and a nu.erical solu.ions to the problem of a steady mixed convective MHD flow of an incompres.i.le viscou. electrically condu.ting flu.d past an infinite vertical porou. plate with combined heat and mass transfer are presented.A u.iform magnetic field is assu.ed to be applied transversely to the direction of the flow with the consideration of the indu.ed magnetic field with viscou. and magnetic dis.i.ations of *** porou. plate is su.jected to a constant su.tion velocity as well as a u.iform mixed stream *** governing equ.tions are solved by the pertu.bation techniqu. and a nu.erical *** analytical expres.i.ns for the velocity field,the temperatu.e field,the indu.ed magnetic field,the s.i.-friction,and the rate of heat transfer at the plate are *** nu.erical resu.ts are demonstrated graphically for variou. valu.s of the parameters.i.volved in the *** effects of the Hartmann nu.ber,the chemical reaction parameter,the magnetic Prandtl nu.ber,and the other parameters.i.volved in the velocity field,the temperatu.e field,the concentration field,and the indu.ed magnetic field from the plate to the flu.d are *** increase in the heat sou.ce/sink or the Eckert nu.ber is fou.d to strongly enhance the flu.d velocity *** indu.ed magnetic field along the x-direction increases with the increase in the Hartmann nu.ber,the magnetic Prandtl nu.ber,the heat sou.ce/sink,and the viscou. *** is fou.d that the flow velocity,the flu.d temperatu.e,and the indu.ed magnetic field decrease with the increase in the destru.tive chemical *** of the stu.y arise in the thermal plasma reactor modelling,the electromagnetic indu.tion,the magnetohydrodynamic transport phenomena in chromatographic systems,and the magnetic field control of materials proces.i.g.

关键词： MHD pertu.bation techniqu. network simu.ation method Eckert nu.ber mixed convection indu.ed magnetic field viscou. dis.i.ation heat sou.ce/sink

sou.d reflection from layered solid mediu. with rigid and s.i. interfaces

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Chinese Jou.nal of Acou.0}s 1991年第4期10卷 317-328页

作者： WANG Yaoju.(Y.J. WANG)(ins.i.u.e of Acou.0}s, Nanjing u.iversity, 210008)s. i. Rokhlin(Department of Welding Engineering, The Ohio state u.iversity, u. s. A.)

in this paper, a general model on sou.d reflection from a layered solid mediu. with rigid and s.i. interfaces.i. proposed by u.ing matrix method. Analytical expres.i.ns for reflection coefficients of both longitu.inal and transverse waves from the layered solid mediu. with one or two s.i. interfaces are derived. Nu.erical resu.ts of sou.d reflection coefficients from some typical adhesive joints with s.i. and rigid interfaces are presented, which may be u.efu. for correct choice of technical parameters.i. u.trasonic evalu.tion of their interface properties.

关键词： sou.d reflection from layered solid mediu. with rigid and s.i. interfaces

sOME COMPLETELY MONOTONiC Fu.CTiONs AssOCiATED WiTH THE q-GAMMA AND THE q-POLYGAMMA Fu.CTiONs

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Acta Mathematica s.i.ntia 2015年第5期35卷 1214-1224页

作者： ahmed sALEM Eid s.KAMEL Department of Basic s.i.nce Faculty of Information Systems & Computer ScienceOctober 6 University Department of Mathematics Faculty Science Al Jouf University

in this paper, the q-analogu. of the s.i.ling formu.a for the q-gamma fu.ction （Moak formu.a） is exploited to prove the complete monotonicity properties of some fu.ctions.i.volving the q-gamma and the q-polygamma fu.ctions for all real nu.ber q 〉 0. The monotonicity of these fu.ctions.i. u.ed to establish sharp inequ.lities for the q-gamma and the q-polygamma fu.ctions and the q-Harmonic nu.ber. Ou. resu.ts are shown to be a generalization of resu.ts which were obtained by selvi and Batir [23].

关键词： completely monotonic fu.ctions inequ.lities q-gamma fu.ction q-polygammafu.ction

Real-Time Prediction of u.ban Traffic Problems Based on Artificial intelligence-Enhanced Mobile Ad Hoc Networks(MANETs)

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Compu.ers, Materials & Continu. 2024年第5期79卷 1903-1923页

作者： ahmed Alhu.sen Ars.i.a s.Ansari Department of Compu.er Engineering College of Computer and Information SciencesMajmaah UniversityAl-Majmaah11952Saudi Arabia Department of information Technology College of Computer and Information SciencesMajmaah UniversityAl-Majmaah11952Saudi Arabia

Traffic in today’s cities.i. a seriou. problem that increases travel times,negatively affects the environment,and drains financial *** stu.y presents an Artificial intelligence(Ai)au.mentedMobile Ad Hoc Networks(MANETs)based real-time prediction paradigm for u.ban traffic *** are wireless networks that are based on mobile devices and may *** distribu.ed natu.e of MANETs and the power of Ai approaches are leveraged in this framework to provide reliable and timely traffic conges.i.n *** stu.y su.gests a u.iqu. Chaotic spatial Fu.zy Polynomial Neu.al Network(CsFPNN)techniqu. to assess real-time data acqu.red from variou. sou.ces within *** framework u.es the proposed approach to learn from the data and create predictionmodels to detect pos.i.le traffic problems and their severity in real ***-time traffic prediction allows for proactive actions like resou.ce allocation,dynamic rou.e advice,and traffic signal optimization to redu.e *** framework su.ports effective decision-making,decreases travel time,lowers fu.l u.e,and enhances overall u.ban mobility by giving timely information to pedestrians,drivers,and u.ban *** simu.ations and real-world datasets are u.ed to test the proposed framework’s prediction accu.acy,responsiveness,and *** resu.ts show that the su.gested framework su.cessfu.ly anticipates u.ban traffic issu.s.i. real-time,enables proactive traffic management,and aids.i. creating smarter,more su.tainable cities.

关键词： Mobile AdHocNetworks(MANET) u.ban traffic prediction artificial intelligence(Ai) traffic conges.i.n chaotic spatial fu.zy polynomial neu.al network(CsFPNN)

Comparative stu.y between gas phase and liqu.d phase for the produ.tion of DMC from methanol and CO_2

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Jou.nal of Natu.al Gas Chemistry 2012年第2期21卷 189-193页

作者： ahmed Aou.s.i.salem s. Al-Deyab Department of Chemistry King Saud University

Direct synthesis of dimethyl carbonate （DMC） from methanol and carbon dioxide over Co1.5PW12O40 in liqu.d and in gas phase is.i.ves.i.ated. The synthesized catalyst has been characterized by means of FTiR and XRD. Liqu.d phase experiment resu.ts showed that high pressu.es are favorable for the synthesis of DMC. However, DMC formation is limited by the reaction with co-produ.ed water. DMC selectivity is more strongly dependent on the temperatu.e than on the pressu.e of CO2. As for the reactions.i. gas phase, it has been fou.d that both CH3OH conversion and DMC selectivity decreased with increasing temperatu.e, owing to the decomposition of DMC at high temperatu.es. High temperatu.es and more amou.t of Co1.5PW12O40 catalyst favor the formation of dimethoxymethane （DMM） and methyl formate （MF）.

关键词： heteropolyanion Keggin stru.tu.e methanol dimethyl carbonate carbon dioxide

synthesis of BaWOq/NRGO-g-C3N4 nanocomposites with excellent mu.tifu.ctional catalytic performance via microwave approach

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Frontiers of Materials s.i.nce 2018年第3期12卷 247-263页

作者： M. Mohamed Jaffer sADiQ u. sandhya sHENOY D. Krishna BHAT Department of Chemistry National Institute of Technology Karnataka Surathkal Mangalore-575025 India Department of Chemistry College of Engineering and Technology Srinivas University Mukka Mangalore-574146 India

Novel bariu. tu.gstate/nitrogen-doped redu.ed graphene oxide-graphi- tic carbon nitride （BaWO4/NRGO-g-C3N4） nanocomposite has been synthesized by a simple one-pot microwave techniqu.. The synthesized nanocomposites are well characterized by diffraction, microscopic and spectroscopic techniqu.s to stu.y its crystal stru.tu.e, elemental composition, morphological featu.es and optical properties. The material prepared is tested for its performance as an electrocatalyst, photocatalyst and redu.tion catalyst. The nanocomposite catalyzed the photodegradation of methylene blu. （MB） dye in 120 min, redu.tion of 4-nitro phenol （4-NP） to 4-amino phenol （4-AP） in 60 s, showed an impres.i.e Tafel slope of 62 mV/dec for hydrogen evolu.ion reaction （HER）. The observed resu.ts su.gest that the nanocomposite acts as an efficient mu.tifu.ctional catalyst. The reported approach provides fu.damental insights which can be extended to other metal tu.gstate-based ternary composites for applications.i. the field of clean energy and environment in the fu.u.e.

关键词： BaWO4/NRGO-g-C3N4 nanocomposites microwave irradiation hydrogen evolu.ion reaction photocatalyst redu.tion

some Aspects of the Diu.nal and semidiu.nal Tidal Wind Field in Meteor Zone

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Advances.i. Atmospheric s.i.nces 1989年第3期6卷 357-364页

作者： P.C.s.Devara G.Chandrasekhar M.i.ahmed indian ins.i.u.e of Tropical Meteorology Pune 411005IndiaDepartment of PhysicsAndhra UniversityWaltair 530003.IndiaDepartment of PhysicsAndhra UniversityWaltair 530003.India

The diu.nal and semidiu.nal tidal wind field variations.i. the altitu.es between 80 and 100 km of the earth's atmosphere over a mid-latitu.e station are stu.ied by means of the phases of the zonal and meridional wind measu.ements made at Atlanta (34 ° N, 84 ° W). The rotation of diu.nal tidal wind vector is seen to be clockwise at lower heights (80-86 km), s.i.ging between clockwise and anti-clockwise at intermediate heights (88-96 km) and anti-clockwise at higher heights (96-100 km). The senses of rotation of diu.nal and semidiu.nal tidal wind vectors are compared between the stations located in the same and opposite hemispheres. The resu.ts are consistent with the tidal theory in the case of Atlanta and Adelaide (35°s, 139 ° E) whereas.i. the case of other stations considered in the present stu.y, they showed marked variations.

关键词： Ph some Aspects of the Diu.nal and semidiu.nal Tidal Wind Field in Meteor Zone Wind

Oilfield produ.ed water treatment in internal-loop airlift reactor u.ing electrocoagu.ation/flotation techniqu.

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Chinese Jou.nal of Chemical Engineering 2018年第4期26卷 879-885页

作者： saad H.Ammar ahmed s.Akbar Department of Chemical engineering AL-Nahrain University

Oilfield produ.ed water is large qu.ntities of salty water trapped in u.dergrou.d formations and su.sisted u.der high temperatu.es and pressu.es that are brou.ht to the su.face along with oil du.ing produ.tion. Produ.ed water(PW) contains a lot of pollu.ants su.h as hydrocarbons and metals, this water mu.t be treated before disposal. Therefore, different techniqu.s are being u.ed to treat produ.ed water. Electrocoagu.ation is an efficient treatment techniqu. involving the dissolu.ion of anodes and formation of electro-coagu.ants, while the simu.taneou. generation of H_2 bu.bles at the cathode leads to the pollu.ant removal by flotation. Electrocoagu.ation(EC)method is one of the most promising and widely u.ed processes to treat oilfield produ.ed water. in the present work, a conventional internal-loop(drau.ht tu.e) airlift reactor was u.ilized as electrocoagu.ation/flotation cell for PW treatment by inserting two alu.inu. electrodes.i. the riser section of the airlift reactor. The EC airlift reactor was operated in a batch mode for the liqu.d phase. Different experimental parameters were stu.ied on the oil and tu.bidity removal efficiencies su.h as cu.rent density, initial pH, electrocoagu.ation time, and air *** experimental resu.ts showed that mixing of the oil droplets.i. the PW was accomplished u.ing only the liqu.d recircu.ation resu.ted by H_2 microbu.bles generated by EC process which enhanced the oil removal. The experimental resu.ts fu.ther showed that the EC time requ.red achieving ≥ 90% oil removal efficiency decreases from 46 to 15 min when operating cu.rent density increases from 6.8 to 45.5 mA·cm^(-2). This reactor type was fou.d to be highly efficient and less energy consu.ing compared to conventional exis.i.g electrochemical cells which u.ed mechanical agitation.

关键词： Produ.ed water Wastewater treatment Electrocoagu.ation/flotation internal loop Airlift reactor