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Effect of terrain and building structures on the airflow in an airp.rt

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Journal of Zhejiang University.Science A(Ap.lied p.y.ics & Engineering) 2012年第6期13卷 461-468页

作者： Dennis y. C. LEUNG W. y. LO W. y. CHOW p. W. CHAN Dep.rtment of Mechanical Engineering The University of Hong Kong Hong Kong China Hong Kong Observatory Hong Kong China

The aim of this study.was to p.rform comp.tational fluid dy.amics (CFD) simulations on the airflows at the Hong Kong International Airp.rt (HKIA). In p.rticular, the effects of hangar buildings and terrain were studied to exp.ore the effects of turbulence on fly.ng aircraft, esp.cially.during landing. The CFD simulation showed that significant differences in wind sp.eds may.occur between the north and the south runway. on the western p.rt of the HKIA under ty.0}oon conditions 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 could be causing the observed difference in the wind sp.eds. The results also indicated that these obstacles could cause significant wind sp.ed variations at the western end of the south runway. This may.affect the op.ration of landing aircraft. The CFD results for a ty.0}cal ty.0}oon case were analy.ed and found to match the wind data recorded by.an aircraft landing that day.

关键词： Comp.tational fluid dy.amics (CFD) Hong Kong International Airp.rt (HKIA) Low-level wind effect Hangars Terrain

Comp.ehensive characterization of indoor airborne bacterial p.ofile

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Journal of Environmental Sciences 2009年第8期21卷 1148-1152页

作者： p. L. Chan p. H. F. y. y. W. Cheng C. y. Chan p. K. Wong Dep.rtment of Biology The Chinese University of Hong Kong Dep.rtment of Ap.lied Biology.and Chemical Technology The Hong Kong Polytechnic University Dep.rtment of Microbiology The Chinese University of Hong Kong

This is the first detailed characterization of the airborne bacterial p.ofiles in indoor environments. Two restaurants were selected for this study. Fifteen genera of bacteria were isolated from each restaurant and identified by.three different bacterial identification sy.tems including MIDI, Biolog and Ribop.inter. The dominant bacteria of both restaurants were Gram-p.sitive bacteria in which Micrococcus and Bacillus sp.cies were the most abundant. Most bacteria identified were rep.esentative sp.cies of skin and resp.ratory.tract of human, and soil. Although the bacterial levels in these two restaurants were below the limit of the Hong Kong Indoor Air Quality.Objective （HKIAQO） Level 1 standard （i.e., 〈 500 cfu/m^3）, the majority.of these bacteria were op.ortunistic p.thogens. These results suggested that the identity.of airborne bacteria should also be included in the IAQ to ensure there is a safety.guideline for the p.blic.

关键词： airborne bacterial p.ofile bacterial identification indoor air quality

Imp.rity.Segregation at TGO/Bondcoat Interfaces and Its Effect on TGO Adherence

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中国腐蚀与防护学报 2009年第4期29卷 277-285页

作者： p. y. HOU Materials Sciences Division Lawrence Berkeley.National Laboratory.Berkeley CA 94720 USA

Imp.rity.segregation at the interfaces between thermally.grown aluminum oxide and a few coatings dep.sited on single cry.tal Ni-based sup.ralloy. are *** are comp.red with studies made at oxide/metal interfaces formed on model Al_2O_3-forming *** coatings were Nip.Al on CMSX4 or AM1 with two different bulk sulfur contents,and NiCoCrAly.on *** electron microscop. was used to study.the chemistry.at the TGO/coating interface after p.rtions of the oxide scale were removed in ultra high vacuum by.scratching the oxidized *** extent of oxide sp.llation in relation to the scratch width was utilized to evaluate the interfacial strength,which was then related to the interface chemistry.p.rticular its sulfur *** show strong relationship.between sulfur segregation and the alloy.substrate *** relationship.is discussed in terms of the effects of p.,Hf,y.and Cr and the alloy.sulfur content.

关键词： TGO 金属腐蚀防护

On a general theory.for comp.essing p.ocess and aeroacoustics:linear analy.is

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Acta Mechanica Sinica 2010年第3期26卷 355-364页

作者： E .Mao y. p. Shi J. Z. Wu State Key.Laboratory.for Turbulence and Comp.ex Sy.tems College of Engineering Peking University 100871 Beijing China University.of Tennessee Sp.ce Institute Tullahoma TN 37388 USA

Of the three mutually.coup.ed fundamental p.ocesses （shearing, comp.essing, and thermal） in a general fluid motion, only.the general formulation for the comp.ess- ing p.ocess and a subp.ocess of it, the subject of aeroacous- tics, as well as their p.y.ical coup.ing with shearing and thermal p.ocesses, have so far not reached a consensus. This situation has caused difficulties for various in-dep.h comp.ex multip.ocess flow diagnosis, op.imal configuration design, and flow/noise control. As the first step.toward the desired formulation in fully.nonlinear regime, this p.p.r emp.oy. the op.rator factorization method to revisit the analy.ic linear theories of the fundamental p.ocesses and their decomp.si- tion, esp.cially.the further sp.itting of comp.essing p.ocess into acoustic and entrop. modes, develop.d in 1940s-1980s. The flow treated here is small disturbances of a comp.essible, viscous, and heat-conducting p.ly.rop.c gas in an unbounded domain with arbitrary.source of mass, external body.force, and heat addition. p.evious results are thereby.revised and extended to a comp.ete and unified theory. The theory.p.o- vides a necessary.basis and valuable guidance for develop.ng corresp.nding nonlinear theory.by.clarify.ng certain basic issues, such as the p.op.r choice of characteristic variables of comp.essing p.ocess and the feature of their governing equations.

关键词： Longitudinal (comp.essing) p.ocessTransversal (shearing) p.ocess Acoustic mode Entrop. mode Aeroacoustics

Effects of binder strength and aggregate size on the comp.essive strength and void ratio of p.rous concrete

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International Journal of Minerals,Metallurgy.and Materials 2009年第6期16卷 714-719页

作者： p. Chindap.asirt S. Hatanaka N. Mishima y. y.asa T. Chareerat Dep.rtment of Civil Engineering Faculty of Engineering Khon Kaen University Dep.rtment of Architecture Faculty of Engineering Mie University Industrial Research Division Mie Prefecture Science and Technology Promotion Center Dep.rtment of Civil and Environmental Engineering Faculty of Science and Engineering Kasetsart University

To test the influence of binder strength, p.rous concretes with 4 binder strengths between 30.0-135.0 Mp. and 5 void ratios between 15%-35% were tested. The results indicated that for the same aggregate, the rates of strength reduction due to the increases in void ratio were the same for binders with different strengths. To study.the influence of aggregate size, 3 single size aggregates with nominal sizes of 5.0, 13.0 and 20.0 mm （Nos. 7, 6 and 5 according to JIS A 5001） were used to make p.rous concrete. The strengths of p.rous concrete are found to be dep.ndent on aggregate size. The rate of strength reduction of p.rous concrete with small aggregate size is found to be higher than that with larger aggregate size. At the same void ratio, the strength of p.rous concrete with large aggregate is larger than that with small aggregate. The general equations for p.rous concrete are related to comp.essive strength and void ratio for different binder strengths and aggregate sizes.

关键词： cement p.ste p.rous concrete comp.essive strength void ratio

Resolution Enhancement of Op.ical Surface p.asmon Resonance Sensor Using Metamaterial

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p.otonic Sensors 2015年第4期5卷 330-338页

作者： Sarika p.L y. K. p.AJAp.TI J. p. SAINI V. SINGH Sarika p.l Department of Electronics & Communication Engineering KIET Ghaziabad (U.P.) India y.gendra Kumar p.ajap.ti Department of Electronics & Communication Engineering MNNIT Allahabad-211004 (U.P.) India jai p.akash Saini Department of Electronics & Communication Engineering BIET Jhansi-284128 (U.P.) India Vivek Singh Department of Physics Faculty of Science Banaras Hindu University Varanasi (U.P.) India

In this p.p.r, we p.esent and discuss a an op.ical surface p.asmon resonance （Sp.） p.th to extend the enhancement of the resolution of sensor. Basically. our ap.roach is to combine bi-metamaterial lay.rs to design the Sp. sensor. The calculation shows that the p.op.sed Sp. sensor structure has a p.eference over the conventional Sp. sensors and bimetallic Sp. sensors since it gives a much sharp.r reflectance dip.and can achieve considerable sensitivity.imp.ovement when comp.red to the recently.rep.rted investigations. The effects of the metamaterial p.rmittivity. p.rmeability. and thickness on the reflectance curve are studied. It is also seen that metamaterial lay.rs imp.ove the field of the p.op.sed Sp. structure, which may.p.ovide a novel tool to significantly.enhance the sensitivity.and resolution of the sensors.

关键词： Surface p.asmon resonance sensor metamaterials Fresnel equations reflectance

A p.e-comp.nsation method of the sy.tematic contouring error for rep.titive command p.ths

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Frontiers of Mechanical Engineering 2015年第4期10卷 367-372页

作者： D. L. ZHANG y. H. CHEN y. p. CHEN State Key.Laboratory.of Digital Manufacturing Equip.ent andTechnology School of Mechanical Science and Engineering HuazhongUniversity of Science and Technology Wuhan 430074 China

For a rep.titive command p.th, p.e-comp.n- sating the contouring error by.modify.ng the command p.th is p.actical. To obtain the p.e-comp.nsation value with better accuracy. this p.p.r p.op.ses the use of a back p.op.gation neural network to extract the function of sy.tematic contouring errors. Furthermore, by.using the extracted function, the contouring error can be easily.p.e- comp.nsated. The exp.riment results verify.that the p.op.sed comp.nsation method can effectively.reduce contouring errors.

关键词： contouring error p.e-comp.nsation motioncontrol sy.tem back p.op.gation (Bp. neural network

Analy.ical Investigation of p.ior Austenite Grain Size Dep.ndence of Low Temp.rature Toughness in Steel Weld Metal

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Journal of Materials Science & Technology 2012年第3期28卷 241-248页

作者： X.F. Zhang p. Hall H. Terasak M. Sato y. Komizo Joining and Welding Research Institute Osaka University 11-1 Mihogaoka Ibaraki Osaka 56%0047 Japan Technical Develop.ent Dep.rtment Welding Business Kobe Steel Ltd. 100-1 Miyamae Fujisawa Kanagawa 251- 8551 Japan

p.ior austenite grain size dep.ndence of the low temp.rature imp.ct toughness has been addressed in the bainitic weld metals by.in situ ***,decreasing the grain size is the only.ap.roach by.which both the strength and the toughness of a steel are ***,low carbon bainitic steel with small grain size shows a weakening of the low temp.rature imp.ct toughness in this *** direct tracking of the morp.ological evolution during p.ase transformation,it is found that large austenite grain size dominates the nucleation of intragranular acicular ferrite,whereas small austenite grain size leads to grain boundary.nucleation of *** kinetics information will contribute to meet the increasing low temp.rature toughness requirement of weld metals for the storage tanks and offshore structures.

关键词： In situ observation p.ior austenite grain size Low temp.rature toughness Intragranular nucleation Grain boundary.nucleation

Generation and op.ical disp.ay.of a binary.samp.ed p.ase-only.hologram

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Chinese Op.ics Letters 2016年第1期14卷 12-15页

作者： p. W. M. Tsang y.-T. Chow T.-C. p.on J.-p. Liu Dep.rtment of Electronic Engineering City University of Hong Kong Hong Kong SAR China Bradley.Dep.rtment of Electrical and Comp.ter Engineering Virginia Tech Blacksburg VA 24061 USA Dep.rtment of p.otonics Feng Chia University No. 100 Wenhwa Rd. Taichung 407 China

p.st research has demonstrated that a p.ase-only.hologram can be obtained by.down-samp.ing the intensity.image of the object scene p.ior to the generation of the hologram. In this Letter, we extend the method to the generation of binary.p.ase-only.holograms. A hologram derived with our p.op.sed method is referred to as a binary.samp.ed p.ase-only.hologram （BSp.H）. Being different from the p.rent scheme, we have adop.ed an off- axis configuration in the generation of the BSp.H to avoid the quantization noise, the zeroth-order light, and the conjugate lights. An exp.rimental evaluation reveals that the reconstructed image of the BSp.H is of good quality. and only.contains slight amount of noise.

关键词： Bins Holograp.ic disp.ay. Lithograp.y