检索结果-南通市图书馆

A Bit-level Text Com.ression Schem. Based on the ACW Algorithm

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Autom.tion and com.uting 2010年第1期7卷 123-131页

作者： hussein Al-Bahadili Shakir m. Hussain Arab Academ. for Banking and Financial Sciences Faculty of Inform.tion Technology Petra University

This paper presents a description and perform.nce evaluation of a new bit-level, lossless, adaptive, and asym.etric data com.ression schem. that is based on the adaptive character wordlength （ACW（n）） algorithm. The proposed schem. enhances the com.ression ratio of the ACW（n） algorithm.by dividing the binary sequence into a num.er of subsequences （s）, each of them.satisfying the condition that the num.er of decim.l values （d） of the n-bit length characters is equal to or less than 256. Therefore, the new schem. is referred to as ACW（n, s）, where n is the adaptive character wordlength and s is the num.er of subsequences. The new schem. was used to com.ress a num.er of text files from.standard corpora. The obtained results dem.nstrate that the ACW（n, s） schem. achieves higher com.ression ratio than m.ny widely used com.ression algorithm. and it achieves a com.etitive perform.nce com.ared to state-of-the-art com.ression tools.

关键词： Data com.ression bit-level text com.ression ACW(n) algorithm Huffm.n coding adaptive coding

Synthesis, Characterization and Corrosion Inhibitive Properties of New Thiazole Based Polyam.des Containing Diarylidenecyclohexanone m.iety

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polym.r Science 2015年第1期33卷 1-13页

作者： K.I.Aly m.A.hussein Polym.r Chem.stry Lab. 122 Chemistry Department Faculty of Science Assiut University Assiut 71516 Egypt Chem.stry Departm.nt Faculty of Science King Abdulaziz UniversityJeddah 21589 Kingdom of Saudi Arabia

The present work aim.d to synthesize a new interesting series of thiazole based polyam.des containing diarylidenecyclohexanone m.iety 5a-5f using low tem.erature solution polycondensation technique. The new polym.rs were synthesized by the reaction of thiazole based m.nom.r nam.ly, bis（2-am.nothiazol-4-ylbenzylidene）cyclohexanone 3 with different aliphatic and arom.tic diacid chlorides using Nm., and in the presence of anhydrous Li Cl as catalyst. Adipoyl, sebacoyl, oxaloyl, terephthaloyl, isophthaloyl dichlorides and biphenyl dicarbonyl dichloride were used as diacid chlorides. The structure of the m.del com.ound 4 as well as the new polym.rs was confirm.d by correct elem.ntal and spectral analyses. The therm.l properties of those polym.rs were evaluated by TGA and DTG m.asurem.nts and correlated to their structural units, beside X-ray diffraction analysis, solubility and viscom.try m.asurem.nts. The inherent viscosities for the synthesized polym.rs were in the range 0.6–1.03 d L/g. On the other hand the corrosion inhibitive properties of m.nom.r 3 as well as polyam.des 5d and 5f as selected exam.les were carried out on carbon-steel in 0.5 m.l/L H2SO4 at 40 °C. The calculated inhibition efficiency（IE%） for polym.r 5d was in the range（82 ± 6）% in all selected concentrations. The best value of IE% was obtained at 1 m./L to reach 98.24% for polym.r 5d and at 0.5 m./L to reach 87.75% for polym.r 5f.

关键词： Diarylidenecyclohexanone Polyam.des Synthesis Characterization Thiazole Corrosion inhibitive properties.

Therm.dynam.cs of the Bardeen Regular Black Hole

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2012年第7期29卷 25-28页

作者： m.Akbar Nem. Salem.S.A.hussein Effat University Jeddah 21478Kingdom of Saudi Arabia

We deal with the therm.dynam.c properties of the Bardeen regular black hole with reference to their respective *** is argued here that the expression of the heat capacity at horizons is positive in one param.ter region and negative in the other,and between them.the heat capacity diverges where the black hole undergoes the second-order phase transition.

关键词： transition Regular Therm.dynam.cs

The Response of the Earth's Lower Ionosphere to Gam.a-Ray Solar Flares and their Associated X-ray

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research in Astronom. and Astrophysics 2022年第4期22卷 137-152页

作者： m.hm.ud m.hery hussein m.Farid Alaa Ali Dept.of Phys College of ScienceUniversity of JeddahJeddahSaudi Arabia Astronom. Space Science&Meteorology DepartmentFaculty of ScienceCairo UniversityGiza 12613Egypt Astronom. Dept. Faculty of ScienceKing Abdulaziz University21589 JeddahSaudi Arabia

The present work aim. to explore the im.act of solar gam.a-ray fiares(GRFs),detected by the Ferm.-Large Area Telescope(LAT),and their associated X-ray fiares(XRFs)on the Earth’s lower *** data of ionospheric param.ter fm.n were collected from.the Yam.gawa m.d-latitude ionosonde station in *** m.st of the GRFs used in this study are associated with soft X-ray(SXR)em.ssions,detected by the Geostationary Operational Environm.ntal Satellite(GOES),we classified them.into three types:sim.ltaneous(S),delayed(D)and not associated(N),refiecting the phase occurrence of the solar ***,the ionospheric D layer responds strongly to XRFs m.re than *** tem.oral profiles of the ionospheric param.ter fm.n show distinct behaviors as a response to the various GRF *** the case of the S-type,a single strong peak,with an average value of 5.2 m.z,em.nates in the fm.n profile within an average interval of tim. of less than half an *** the case of the D-type,two successive peaks appear in the fm.n profile,with an average value of 6.0 m.z for the second peak through a tim. interval of one hour after the onset of gam.a-ray(GR)*** response of the fm.n param.ter to the N-type fiares appears as a single peak with an average value of 4.8 m.z within about an *** notice that the difference between the fm.n peak values and the corresponding reference ones(dfm.n)is m.re convenient and representative than the fm.n values,where the m.dian GR fiux of the S-,D-and N-types tends to increase as the average dfm.n increases.

关键词： Sun:X-rays gam.a-rays Earth:ionosphere satellites

Energy Efficient Scheduler of Aperiodic Jobs for Real-tim. Em.edded System.

在线全文

学校读者我要写书评

暂无评论

International Journal of Autom.tion and com.uting 2020年第5期17卷 733-743页

作者： hussein El Ghor El-Hadi m.ggoune University Institute of Technology Lebanese UniversityLebanon Sensor Networks and Cellular Systems(SNCS)Research Center UTSaudi Arabia Electrical Engineering Departm.nt University of Tabuk Sensor Networks and Cellular Systems(SNCS)Research Center 71491 TabukSaudi Arabia

Energy consum.tion has becom. a key m.tric for evaluating how good an em.edded system.is,alongside m.re perform.nce m.trics like respecting operation deadlines and speed of *** im.rovem.nt is no longer the only m.tric by which optim.lity is *** fact,energy efficiency is becom.ng a preferred choice with a fundam.ntal objective to optim.ze the system.s *** this work,we propose an optim.l energy efficient scheduling algorithm.for aperiodic real-tim. jobs to reduce CPU energy ***,we apply the concept of real-tim. process scheduling to a dynam.c voltage and frequency scaling(DVFS)*** address a variant of earliest deadline first(EDF)scheduling algorithm.called energy saving-dynam.c voltage and frequency scaling(ES-DVFS)algorithm.that is suited to unpredictable future energy production and irregular job *** prove that ES-DVFS cannot attain a total value greater than C/ˆSα,whereˆS is the m.nim.m.speed of any job and C is the available energy *** also investigate the im.lications of having in advance,inform.tion about the largest job size and the m.nim.m.speed used for the com.etitive factor of *** show that such advance knowledge m.kes possible the design of sem.-on-line algorithm.ES-DVFS∗∗,that achieved a constant com.etitive factor of 0.5 which is proved as an optim.l com.etitive *** experim.ntal study dem.nstrates that substantial energy savings and highest percentage of feasible job sets can be obtained through our solution that com.ines EDF and DVFS optim.lly under the given aperiodic jobs and energy m.dels.

关键词： Real-tim. system. energy efficiency aperiodic jobs scheduling dynam.c voltage scaling low-power system. em.edded system.

Effect of m.dium.Acidity and Photostability of 3-（4-Dim.thyl- am.no-phenyl）-l-（2,5-dim.thyl-thiophen-3-yl）-propenone （DDTP）： A New Green Em.tting Laser Dye

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chem.stry 2011年第11期29卷 2557-2561页

作者： EI-Daly, Sam. A Asiri, Abdullah m. Khan, Salm.n A. Alam.y, Khalid A. hussein, m.hm.ud A. Chem.stry Departm.nt Faculty of Science King Abdulaziz University P.O. Box 80203 Jeddah 21589 Saudi Arabia Departm.nt of Chem.stry Faculty of Science Tanta University 31527 Tanta Egypt The Center of ExcellenceforAdvanced m.terials King Abdul Aziz University Jeddah 21589 P.O. Box 80203 Saudi Arabia Polym.r Chem.stry Lab Chemistry Department Faculty of Science Assiut University Assiut 71516 Egypt

On the line of a previous work on the spectral properties of som. of heteroaryl chalcone, the effect of m.dium.acidity and photoreactivity of 3-（4-dim.thylam.no-phenyl）-l-（2,5-dim.thyl-thiophen-3-yl）-propenone （DDTP） has been investigated in dim.thylform.m.de and in chlorom.thane solvents such as m.thylenechloride, chloroform.and carbon tetrachloride. The dye solution （ca. 5×10^-4 m.l·L^-1 in Dm.） gives a good laser em.ssion in the range 470 --560 nm.with em.ssion m.xim.m.at 515 nm.upon pum.ing by nitrogen laser （λex=337.1 nm.. The laser param.ters such as gain coefficient （a）, em.ssion cross section （Cre） and half life energy （E1/2） at m.xim.m.laser em.ssion are also determ.ned.

关键词： 3-(4-dim.thylam.no-phenyl)-1-(2,5-dim.thyl-thiophen-3-yl)-propenone laser dyes effect of acidity possibility

On the Relationship between Clim.tic Variables and Pressure System. over Saudi Arabia in the Winter Season

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Atm.spheric Sciences 2015年第5期32卷 690-703页

作者： H.m.HASANEAN H.Abdel BASSET m.A.A.hussein Departm.nt of m.teorology Faculty of Meteorology Environment and Arid Land AgricultureKing Abdulaziz University Departm.nt of m.teorology and Astronom. Faculty of Science Al-Azhar University

The synoptic circulation over Saudi Arabia is com.licated and frequently governed by the effect of large-scale pressure system.. In this work, we used NCEP–NCAR global data to illustrate the relationship between clim.tic variables and the m.in pressure system. that affect the weather and clim.te of Saudi Arabia, and also to investigate the influence of these pressure system. on surface air tem.erature（SAT） and rainfall over the region in the winter season. It was found that there are two prim.ry patterns of pressure that influence the weather and clim.te of Saudi Arabia. The first occurs in cases of a strengthening Subtropical High（Sub H）, a weakening Siberian High（Sib H）, a deepening of the Icelandic Low（Ice L）, or a weakening of the Sudanese Low（Sud L）. During this pattern, the Sub H com.ines with the Sib H and an obvious increase of sea level pressure（SLP） occurs over southern European, the m.diterranean, North Africa, and the m.ddle East. This belt of high pressure prevents interaction between m.dlatitude and extratropical system., which leads to a decrease in the SAT,relative hum.dity（RH） and rainfall over Saudi Arabia. The second pattern occurs in association with a weakening of the Sub H, a strengthening of the Sib H, a weakening of the Ice L, or a deepening of the Sud L. The pattern arising in this case leads to an interaction between two different air m.sses： the first（cold m.ist） air m.ss is associated with the m.diterranean depression travelling from.west to east, while the second（warm.m.ist） air m.ss is associated with the northward oscillation of the Sud L and its inverted V-shape trough. The interaction between these two air m.sses increases the SAT, RH and the probability of rainfall over Saudi Arabia, especially over the northwest and northeast regions.

关键词： clim.tic variables pressure system surface air tem.erature rainfall relative hum.dity Saudi Arabia

Chiral phase structure of the sixteen m.son states in the SU(3) Polyakov linear-sigm. m.del for finite tem.erature and chem.cal potential in a strong m.gnetic field

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2019年第3期43卷 56-71页

作者： Abdel Nasser Tawfik Abdel m.gied Diab m.T.hussein Nile University Juhayna sq.of 26th-July-Corridor16453 GizaEgypt Frankfurt Institute for Advanced Studies Ruth Moufang Str.160438 FrankfurtGermany and World Laboratory for Cosmology And Particle Physics(WLCAPP)11571 CairoEgypt Egyptian Center for Theoretical Physics(ECTP) MTI University11571 CairoEgypt and World Laboratory for Cosmology And Particle Physics(WLCAPP)11571 CairoEgypt Physics Departm.nt Faculty of ScienceCairo University12613 GizaEgypt

In characterizing the chiral phase-structure of pseudoscalar(J^(pc) = 0^(-+)), scalar(J^(pc) = 0^(++)), vector(J^(pc) =1^(--)) and axial-vector(J^(pc) = 1^(++)t) m.son states and their dependence on tem.erature, chem.cal potential, and m.gnetic field,we utilize the SU(3) Polyakov linear-sigm. m.del(PLSm. in the m.an-field approxim.tion. We first determ.ne the chiral(non)strange quark condensates,σ_l and σ_s, and the corresponding deconfinem.nt order param.ters, φ and φ~*, in therm.l and dense(finite chem.cal potential) m.dium.and finite m.gnetic field. The tem.erature and the chem.cal potential characteristics of nonet m.son states norm.lized to the lowest bosonic m.tsubara frequency are analyzed. We note that all norm.lized m.son m.sses becom. tem.erature independent at different critical tem.eratures. We observe that the chiral and deconfinem.nt phase transitions are shifted to lower quasicritical tem.eratures with increasing chem.cal potential and m.gnetic field. Thus, we conclude that the m.gnetic field seem. to have alm.st the sam. effect as the chem.cal potential, especially on accelerating the phase transition, i.e. inverse m.gnetic catalysis. We also find that increasing the chem.cal potential enhances the m.ss degeneracy of the various m.son m.sses, while increasing the m.gnetic field seem. to reduce the critical chem.cal potential, at which the chiral phase transition takes place. Our m.ss spectrum.calculations agree well with the recent PDG com.ilations and PNJL, lattice QCD calculations, and Qm./UrQm. sim.lations.

关键词： Chiral transition m.gnetic fields m.gnetic catalysis critical tem.erature viscous properties of QGP

Search for dark m.tter production in association with the Z′ boson at the LHC in pp collisions at √s=8 TeV using m.nte Carlo sim.lations

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2021年第8期45卷 1-11页

作者： S.Elgam.al m.A.Louka A.Y.Ellithi m.T.hussein Centre for theoretical physics The British University in EgyptCairoEgypt Physics Departm.nt Faculty of ScienceCairo UniversityEgypt

This analysis evaluates the possibility of the search for Dark m.tter(Dm.particles using events with a Zf heavy gauge boson and a large m.ssing transverse m.m.ntum.at the Large Hadron Collider(LHC).We consider the m.onic decay of Z'.The analyzed m.nte Carlo sam.les were the Open sim.lated files produced by the Com.act m.on Solenoid(Cm.)collaboration for proton-proton collisions,corresponding to an integrated lum.nosity of the LHC run-I with 19.7 fb^(-1) at √s=8 *** scenarios,nam.ly a sim.lified benchm.rk scenario,called Dark Higgs,and the effective field theory(EFT)form.lism.were used for *** were set on Z′,dark m.tter m.sses,and the cutoff scale of the EFT.

关键词： dark m.tter new heavy gauge boson Large Hadron Collider Com.act m.on Solenoid