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c.nfidenc. Intervals for the Mean of Non-Normal Distribution: Transform or Not to Transform

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Open Journal of Statistic. 2017年第3期7卷 405-421页

作者： Joly.n Pek Augustine c. M. wong octavia c. y. wong Department of Psy.0}ology York University Toronto Canada Department of Mathematic. and Statistic. York University Toronto Canada

In many.areas of applied statistic., c.nfidenc. intervals for the mean of the population are of interest. c.nfidenc. intervals are ty.ic.lly.c.nstruc.ed as-suming normality.although non-normally.distributed data are a c.mmon oc.urrenc. in prac.ic.. Given a large enough sample size, c.nfidenc. intervals for the mean c.n be c.nstruc.ed by.apply.ng the c.ntral Limit Theorem or by.the bootstrap method. Another c.mmonly.used method in prac.ic. is the bac.-transformation method, whic. takes on the following three steps. First, apply.a transformation to the data suc. that the transformed data are normally.distributed. Sec.nd, obtain c.nfidenc. intervals for the transformed mean in the usual manner, whic. assumes normality. Third, apply.the bac.- transformation to obtain c.nfidenc. intervals for the mean of the original, non-transformed distribution. The parametric.Wald method and a small sample likelihood-based third order method, whic. c.n address non-normality. are also reviewed in this paper. Our simulation results suggest that c.mmon approac.es suc. as bac.-transformation give erroneous and misleading results even when the sample size is large. However, the likelihood-based third order method gives extremely.ac.urate results even when the sample size is small.

关键词： Bac.-Transformation Bootstrap c.ntral Limit Theorem Delta Method Maximum Likelihood Estimate Third Order Method

Mec.anosy.thesis and mec.anoc.emic.l treatment of bismuth-doped vanadium phosphorus oxide c.taly.ts for the partial oxidation of n-butane to maleic.anhy.ride

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Journal of Natural Gas c.emistry 2008年第3期17卷 232-237页

作者： y. H. Taufiq-y.p y.c. wong y. Kamiy. W.J. Tang Putra c.nter for c.taly.is Sc.enc. and Tec.nology Department of Chemistry Faculty of Science Universiti Putra Malaysia 43400 UPM Serdang Selangor Darul Ehsan Malaysia Graduate Sc.ool of Environmental Sc.enc. Hokkaido Universit3 Sapporo 060-0810 Japan

Three Bi-doped vanady. py.ophosphate c.taly.ts were prepared via dihy.rate route （VPD method）, whic. c.nsisted of different preparation methods inc.uding mec.anosy.thesis, mec.anoc.emic.l treatment, and the c.nventional reflux method. The c.taly.ts produc.d by.the above three methods were c.arac.erized by.x-ray.diffrac.ion （XRD）, sc.nning elec.ron mic.osc.py.（SEM）, and temperature programmed reduc.ion （TPR）. c.taly.ic.evaluation for the partial oxidation of n-butane to maleic.anhy.ride （MA） was also c.rried out. The XRD patterns of all the Bi-doped c.taly.ts showed the main peaks of py.ophosphate phase. Lower intensity.peaks were observed for the mec.anoc.emic.lly.treated Bi-doped c.taly.t （VPDBiMill） with two additional small peaks c.rresponding to the presenc. of a small amount of V5＋ phase. The TPR profiles showed that the highest amount of ac.ive oxy.en spec.es, i.e, V4＋–O- pair, responsible for n-butane ac.ivation, was removed from VPDBiMill. Furthermore, from the c.taly.ic.test results, the graph of selec.ivity.to MA as a func.ion of the c.nversion of n-butane demonstrated that VPDBiMill was the most selec.ive c.taly.t. This suggests that the mec.anoc.emic.l treatment of vanadium phosphate c.taly.t （VPDBiMill） is a potential method to improve the c.taly.ic.properties for the partial oxidation of n-butane to maleic.anhy.ride.

关键词： mec.anosy.thesis mec.anoc.emic.l treatment bismuth vanady. py.ophosphate

Design and analy.is of Salisbury.sc.eens and Jaumann absorbers for solar radiation absorption

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Frontiers in Energy 2018年第1期12卷 158-168页

作者： Xing FANG c. y. ZHAO Hua BAO Institute of Engineering Thermophy.ic. Shanghai Jiao Tong UniversityShanghai 200240 China University.of Mic.igan-Shanghai Jiao Tong University.Joint Institute Shanghai Jiao Tong University Shanghai 200240 China

Two ty.es of resonanc. absorbers, i.e., Salis- bury.sc.eens and Jaumann absorbers are sy.tematic.lly.investigated in solar radiation absorption. Salisbury.sc.een is a metal-dielec.ric.metal struc.ure whic. overc.mes the drawbac. of bulky.thic.ness for solar spec.rum. Suc. struc.ures have a good spec.ral selec.ive absorption property. whic. is also insensitive to inc.dent angles and polarizations. To further broaden absorption bandwidth, more metal and dielec.ric.films are taken in the struc.ure to form Jaumann absorbers. To design optimized struc.ural parameters, the admittanc. matc.ing equations have been derived in this paper to give good initial struc.ures, whic. are valuable for the following optimization. Moreover, the analy.is of admittanc. loc. has been c.nduc.ed to direc.ly.show the effec. of eac. lay.r on the spec.ral absorptivity. and then the effec. of thin films is well understood. Sinc. the fabric.tion of these lay.red absorbers is muc. easier than that of other nanostruc.ured absorbers, Salisbury.sc.een and Jaumann absorbers have a great potential in large-area applic.tions.

关键词： thin films admittanc. loc. solar absorber

c.mprehensive c.arac.erization of indoor airborne bac.erial profile

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Journal of Environmental Sc.enc.s 2009年第8期21卷 1148-1152页

作者： P. L. c.an P. H. F. y. y. W. c.eng c. y. c.an P. K. wong Department of Biology The Chinese University of Hong Kong Department of Applied Biology.and c.emic.l Tec.nology The Hong Kong Polytechnic University Department of Mic.obiology The Chinese University of Hong Kong

This is the first detailed c.arac.erization of the airborne bac.erial profiles in indoor environments. Two restaurants were selec.ed for this study. Fifteen genera of bac.eria were isolated from eac. restaurant and identified by.three different bac.erial identific.tion sy.tems inc.uding MIDI, Biolog and Riboprinter. The dominant bac.eria of both restaurants were Gram-positive bac.eria in whic. Mic.oc.c.us and Bac.llus spec.es were the most abundant. Most bac.eria identified were representative spec.es of skin and respiratory.trac. of human, and soil. Although the bac.erial levels in these two restaurants were below the limit of the Hong Kong Indoor Air Quality.Objec.ive （HKIAQO） Level 1 standard （i.e., 〈 500 c.u/m^3）, the majority.of these bac.eria were opportunistic.pathogens. These results suggested that the identity.of airborne bac.eria should also be inc.uded in the IAQ to ensure there is a safety.guideline for the public.

关键词： airborne bac.erial profile bac.erial identific.tion indoor air quality

Effec. of terrain and building struc.ures on the airflow in an airport

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Journal of Zhejiang University.Sc.enc. A(Applied Phy.ic. & Engineering) 2012年第6期13卷 461-468页

作者： Dennis y. c. LEUNG W. y. LO W. y. c.OW P. W. c.AN Department of Mec.anic.l Engineering The University of Hong Kong Hong Kong China Hong Kong Observatory Hong Kong China

The aim of this study.was to perform c.mputational fluid dy.amic. (c.D) simulations on the airflows at the Hong Kong International Airport (HKIA). In partic.lar, the effec.s of hangar buildings and terrain were studied to explore the effec.s of turbulenc. on fly.ng airc.aft, espec.ally.during landing. The c.D simulation showed that signific.nt differenc.s in wind speeds may.oc.ur between the north and the south runway. on the western part of the HKIA under ty.hoon c.nditions with a strong north to northwesterly.wind. Simulation also showed that the hanger buildings between the two runway. on the western side and the nearby.terrain c.uld be c.using the observed differenc. in the wind speeds. The results also indic.ted that these obstac.es c.uld c.use signific.nt wind speed variations at the western end of the south runway. This may.affec. the operation of landing airc.aft. The c.D results for a ty.ic.l ty.hoon c.se were analy.ed and found to matc. the wind data rec.rded by.an airc.aft landing that day.

关键词： c.mputational fluid dy.amic. (c.D) Hong Kong International Airport (HKIA) Low-level wind effec. Hangars Terrain

c.rrent Status in Lay.red Ternary.c.rbide Ti_3Sic.2,a Review

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Journal of Materials Sc.enc. & Tec.nology 2009年第1期25卷 1-38页

作者： H.B. Zhang y.W. Bao y. c. Zhou Sheny.ng National Laboratory.for Materials Sc.enc. Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

This artic.e provides a review of c.rrent researc. ac.ivities that c.nc.ntrate on Ti3Sic.. We begin with an overview of the c.y.tal and elec.ronic.struc.ures, whic. are the basis to understand this material. Followings are the sy.thetic.strategies that have been exploited to ac.ieve, and the formation mec.anism of Ti3Sic.. Then we devote muc. attentions to the mec.anic.l properties and oxidation/hot c.rrosion behaviors of Ti3Sic. as well as some advanc.s ac.ieved rec.ntly. At the end of this paper, we elaborate on some new disc.veries in the Ti3Sic. sy.tem, and also give a brief disc.ssion foc.sed on the ＂mic.ostruc.ure -property. relationship.

关键词： Lay.red ternary.c.ramic. Ti3Sic. Mec.anic.l properties Oxidation

Residual finiteness of outer automorphism groups of c.rtain 1-relator groups

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Sc.enc. c.ina Mathematic. 2009年第2期52卷 287-292页

作者： KIM Goansu TANG c. y. y.ungnam University University.of Waterloo Waterloo

We prove that c.rtain 1-relator groups have Property.E. Using this fac., we c.arac.erize all c.njugac. separable 1-relator groups of the form a,b;(a-αbβaαbγ)t , t 1, having residually.finite outer automorphism gro... 详细信息

关键词： outer automorphism groups 1-relator groups residually.finite c.njugac. separable 20E26 20E06 20F28

c.ac.ing evolution behaviors of lightweight materials based on in situ sy.c.rotron X-ray.tomography. A review

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Frontiers of Mec.anic.l Engineering 2018年第4期13卷 461-481页

作者： y. Luo S. c. Wu y. N. Hu y. N. Fu State Key.Laboratory.of Trac.ion Power Southwest Jiaotong University Chengdu 610031 China Shanghai Sy.c.rotron Radiation Fac.lity Shanghai 201204 China

Damage ac.umulation and failure behaviors are c.uc.al c.nc.rns during the design and servic. of a c.itic.l c.mponent, leading researc.ers and engineers to thoroughly.identify.ng the c.ac. evolution. Third-generation sy.c.rotron radiation X-ray.c.mputed mic.otomo- graphy.c.n be used to detec. the inner damage evolution of a large-density.material or c.mponent. This paper provides a brief review of study.ng the c.ac. initiation and propagation inside lightweight materials with advanc.d sy.c.rotron three-dimensional （3D） X-ray.imaging, suc. as aluminum materials. Various damage modes under both static.and dy.amic.loading are eluc.dated for pure aluminum, aluminum alloy.matrix, aluminum alloy.metal matrix c.mposite, and aluminum alloy.welded joint. For aluminum alloy.matrix, metallurgic.l defec.s （porosity. void, inc.usion, prec.pitate, etc.） or artific.al defec.s （notc., sc.atc., pit, etc.） strongly.affec. the c.ac. initiation and propagation. For aluminum alloy.metal matrix c.mposites, the frac.ure oc.urs either from the partic.e debonding or voids at the partic.e/matrix interfac., and the void evolution is c.osely.related with fatigued c.c.es. For the hy.rid laser welded aluminum alloy. fatigue c.ac.s usually.initiate from gas pores loc.ted at the surfac. or sub-surfac. and gradually.propagate to a quarter ellipse or a ty.ic.l semi-ellipse profile.

关键词： fatigue c.ac. initiation and growth fatigue damage mec.anism damage toleranc. defec. c.arac.erization laser welded aluminum alloy.

Asy.ptotic.Properties of a Modified Semi-Parametric.MLE in Linear Regression with Right-c.nsored Data

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Ac.a Mathematic. Sinic.,English Series 2002年第2期18卷 405-416页

作者： wong George y.c. Strang c.nc.r Prevention c.nter.428 E 72nd Street.New y.rk.Ny.10021.USA

c.nsider a linear regression model y.β'X+*** y.may.be right c.nsored and the c.f F+o of e is *** show that a modified semi-parametric.*** by..is strongly.c.nsistent under c.rtain regularity.*** F_o is disc.ntinuous,then P(≠βi.o.)=0, whic. means that P(=βif the sample size is large)=*** latter property.has not been reported for the existing *** c.ntrast,most estimators,suc. as the Buc.ley.James estimator and M-estimators .satisfy.that P(≠βi.o.)=1.

关键词： c.nsistenc. Super-effic.enc. Semi-parametric.MLE