简介：当前．Linux中已经存在的各种Rootkits,大都是借助可加载内核模块（LKM）来实现的．包括利用IDT实现系统调用的劫持技术来实现文件隐藏、进程隐藏、网络连接的隐藏及模块本身的隐藏等。但这种借助LKM实现的Rootkits,需要依赖操作系统内核模块的支持,若在目标机内核中并没有实现模块支持,那么这种Rootkits是无法加载到目标机中的。大家应该知道,在一台Linux计算机在编辑定制内核时,用户是可以选择是否添加可加载内核模块的支持的,当不选择此支持时,LKM是无效的。而且当前针对LKM实现的Rootkits已经很容易的被各种Rootkits检测工具检测出来,如完整性检测技术、针对攻击系统调用的检测技术等。

简介：嘹亮的钟声敲向天上的浮云,敲向霜冻的微光送向荒寂高空;旧岁在黑夜中悄悄辞別;嘹亮的钟声在送別旧岁。

简介：1,2-rearrangementsofcarbenes:CCH2X（X=CH2,NHandO）arestudiedbyusingabinitiogradientmethod.HeteroatomsNandOstabilizethecarbeneanddecreaseitsreactivity,mainlybychangingfrontiermolecularorbitals,butretainthewayofthereaction.ThereactionstartsfromtheattackofthemigratinghydrogenonthecarbenepAOandendswiththeentranceofthehydrogenintothecarbeneσorbital.ReactivitiesareintheorderofX=CH2>NH>O.Thereactionisexothermicorendothermicaccordingtowhethertheproductisa4n+2or4nπelectronmolecule.

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简介：Helenboughtaverynicering(戒指)andsheworeittotheofficethenextday.Nobodysawherring.Shemovedherhandthiswayandthat,butstillnobbdyintheoffieesawtheringonherfinger.Atteatimewhentheyweresitting'round,shesuddenly(突然地)stoodup.“itisveryhothere,”shesaid.“IthinkI'lltakeoffmyring.”

简介：如果你有一个机会得到你想要或想做的承诺时，你会怎么做?让我们一起来看看这位年青的农民是如何对待他的机遇的。

简介：WhenMarywasfourteen,hermothergaveherabeautifulring.ItwasabirthdaypresentandMarywasverypleased.Aweeklatershewaslostherring.Shelookedeverywherebutshecouldnotfindthering.Shelookedinthedustbinoutsidethekitchenbutherringwasnotthere.

简介：PlanarringresonatorwaveguidesarefabricatedinthinfilmsofAs2S3chalcogenideglass,depositedonsilicaon-siliconsubstrates.WaveguidecoresaredirectlywrittenbyscanningthefocusedilluminationofafemtosecondTi:sapphirelaseratacentralwavelengthof810nm,throughatwo-photonphoto-darkeningprocess.Alargephotoinducedindexchangeof0.3–0.4refractiveindexunitsisobtained.Theradiusoftheringresonatoris1.9mm,correspondingtoatransmissionfreespectralrangeof9.1GHz.Ahighloaded（intrinsic）Qvalueof110,000（180,000）isachieved.Thethermaldependenceoftheresonatortransferfunctionischaracterized.Theresultsprovidethefirstreport,tothebestofourknowledge,ofdirectlywrittenhigh-Qringresonatorsinchalcogenideglassfilms,anddemonstratethepotentialofthissimpletechniquetowardsthefabricationofplanarlightguidecircuitsinthesematerials.

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简介：AbstractPurpose:Combined anterior and posterior ring (APR) fixation is classically performed in Tile B2 and C1 injuries to achieve superior biomechanical stability. However, the posterior ring (PR) is the main weight bearing portion that is responsible for weight transmission from the upper parts of the body to the lower limbs through the sacrum and the linea terminalis. It is hypothesized that isolated PR fixation can achieve comparable radiological and clinical outcomes to APR fixation. Therefore, we conducted this study to compare the two fixation principles in managing Tile B2 and C1 injuries.Methods:Our study included 20 patients with Tile B2 injuries and 20 patients with Tile C1 injuries. This study was a randomized control single-blinded study via computerized random numbers with a 1:1 allocation by using random block method. The study was performed at a level one trauma center. A total of 40 patients with Tile B2 and C1 injuries underwent combined APR or isolated PR fixation (Group A and B, respectively). Matta & Tornetta radiological principles and Majeed pelvic scoring system were used for the assessment of primary outcomes and postoperative complications. Secondary outcomes included operative time, amount of blood loss, intraoperative assessment of reduction, need of another operation, length of hospital stay, ability to weight bear postoperatively and pain control metrics. We used student t-test to compare the difference in means between two groups, and Chi-square test to compare proportions between two qualitative parameters. We set the confidence interval to 95% and the margin of error accepted to 5%. So, p ≤ 0.05 was considered statistically significant.Results:The mean follow-up duration was 18 months. The operative time (mean difference 0.575 h) and the intraoperative blood loss (mean difference 97.5 mL) were lower in Group B. Also, despite the higher frequency of rami displacement before union in the same group, there were no significant differences in terms of radiological outcome (excellent outcome with OR = 2.357), clinical outcome (excellent outcome with OR = 2.852) and postoperative complications assessment (OR = 1.556) at last follow-up.Conclusion:The authors concluded that isolated PR fixation could favorably manage Tile B2 and C1 pelvic ring injuries with Nakatani zone II pubic rami fractures and intact inguinal ligament. Its final radiological and clinical outcomes and postoperative complications were comparable to combined APR fixation, but with less morbidity (shorter operation time, lower amount of blood, and no records of postoperative wound infection).

简介：Ringinversionofeightsubstituted2-phenyl-4,4-dimethyloxazolidinesino-dichloro-benzene-d4wasstudiedbyHDNMR.Veryhighinversionbarriers(/nGc/n=86.7—93.4kJ·mol-1)werefoundfortheseoxazolidinerings.Themagnitudeoftheinversionbarrierisdependentonthepolarityofthesubstituentonthephenylgroup.Alinearcorrelationispresentbetweenthe/nGc/noftheinversionandthesubstituentconstant,σ+,ofthesubstituent.

简介：Thebindingenergyofexcitonsconfinedtoaquantumringundertheinfluenceofperpendicularhomogeneousmagneticfieldiscalculatedasafunctionoftheringradius.Calculationsaremadebyusingthemethodofexactdiagonalizationwithintheeffective-massapproximation.Thefeatureofbindingenergyofthegroundstateasafunctionoftheringradiusforseveralvaluesofthemagneticfieldhasbeenrevealed.Theinterestingfeatureofourstudyisthat,inaquantumring,thegeometricstructureofexcitonsmayrevealtransition.

简介：Coldringrollingisanadvancedbutcomplexmetalformingprocessundercoupledeffectswithmulti-factors,suchasgeometrysizesofrollsandringblank,material,formingprocessparametersandfriction,etc.Amongthesefactors,frictionbetweenrollsandringblankplaysanimportantroleinkeepingthestableformingofcoldringrolling.Ananalyticalmethodwasfirstlypresentedforproximatelydeterminingthecriticalfrictioncoefficientofstableformingandthenamethodwasproposedtodeterminethecriticalfrictioncoefficientbycombininganalyticalmethodwithnumericalsimulation.Andtheinfluenceoffrictioncoefficientonthequalityofend-planeandsidespreadofring,rollingforce,rollingmomentandmetalflowcharacteristicinthecoldringrollingprocesshavebeenexploredusingthethreedimensional(3D)numericalsimulationbasedontheelastic-plasticdynamicfiniteelementmethod(FEM)undertheABAQUSsoftwareenvironment,andtheresultsshowthatincreasingthefrictiononthecontactsurfacesbetweenrollsandringblankisusefulnotonlyforimprovingthestabilityofcoldringrollingbutalsoforimprovingthegeometryanddimensionprecisionofdeformedring.

简介：Oncetherelivedtwobirds.Theywereneighbours.Theyhadknowneachothersincetheywereborn.Theyplayedtogetherandhelpeachotherwhentheywereyoung.Thegirlfellinlovewiththeboyandtheboylovedthegirlverymuchwhentheygrewup.

简介：TheauthorgivessimplecharacterizationoftheHenselizationofanexcellentregularlocalring.

简介：ABSTRACT:Westudytheevolutionofsingleellipticvortexringforinitialaspectratio(AR)=2,4,6.TheincompressibleNavier-Stokesequationsaresolvedbyadealiasedpseudo-spectralmethodwith64~3gridpointsinaperiodiccube.WefindthattherearethreekindsofvortexmotionasARincreasesandvortexbifurcationoccursatacertainAR.Theprocessesofadvection,interaction,anddecayofvortexringareanalyzed.Numericalresultscoincidewithexperimentsandothernumericalsimulations.

简介：Inthispaper,notonlyvariouscharacterizationsofcentralelementofmatrixringaregiven,butalsotheindexofcentralelementofmatrixringisdecided.Finally,anaddition-aldiscussiononthoseproblemsisprovidedtoo.1Introduction

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