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Journal of thermal Science 2002年第3期11卷 259-270页

作者： B.Deng t.t.wong W.Q.tao School of Power and Energy Xi’an Jiaotong University Xi’an China Department of Mechanical Engineering The Hong Kong Polytechnic University Hong Kong

Experiments were conducted to investigate the forced convective heat transfer and flow friction of turbulent airflow in a rectangular duct with cross-ribs attached at the two principal walls in the Reynolds number range from 5000 to 40000. the effect of the rib cross angle (45° 60° 75° and the height (4 mm, 5 mm) of the cross-ribs on the forced convection and flow friction were tested. Non-dimensional correlations for the duct average Nusselt number and friction factor of cross-ribs duct were developed from the test data. Experiments were also conducted for the corresponding parallel ribs to compare their relative performance. the experimental results show that both of the convective heat transfer coefficient and friction factor were increased with cross-ribs, with 45°cross-ribs being the best. Compared with parallel ribs normal to the flow direction under identical flow rate and identical pumping power constraints, the cross-ribs can enhance heat transfer in the lower Reynolds number region, while

关键词： cross-ribs forced convection heat transfer enhancement.

Estimating Effective Reproduction Number for SIR Compartmental Model:A Stochastic Evolutionary Approach

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Journal of Social Computing 2022年第2期3卷 182-189页

作者： W.k.wong Filbert H.Juwono the Department of Electrical and Computer Engineering Curtin University MalaysiaMiri 98009Malaysia

Compatmental pandemic models have become a significant tool in the battle against disease *** this,pandemic models sometimes require extensive modification to accuately reflect the actual epidemic condition the Susceptble-Infectious-Removed(SIR)model,in particular,contains two primary parameters:the infectious rate parameter ρ and the removal rate parameter r,in addition to additional unknowns such as the initial infectious *** to the complexity,there is an obvious challenge to tack the evolution of these parameters,especially ρ and γ,over time which leads to the estimation of the reproduction number for the paticular time window,^(κ)*** reproduction mumber may provide better understanding on the efectiveness of isolation or control *** changing ^(κ)t values(evolving over time window)will lead to even more possible parameter *** the present Coronavirus Disease 2019(COVID-19)pandemic,a stochastic optimization stategy is proposed to ft the model on the basis of parameter changes over *** are encoded to reflet the changing parameters of tρ and γt,alwing the changing ^(κ)t to be *** our approach,an Adaptive Differential Evolution(ADE)and Paricle Swam Optimization(PSO)are used to ft the curves into previously recorded *** eliminates the need to tume the parameters of the Differential Evolution(DE)to balance the exploitation and exploration in the solution *** show that the proposed optimized model can generally ft the cuves well albeit high variance in the solutions.

关键词： Susceptible-Infectious-Removed(SIR)model adaptive differential evolution Coronavirus Disease 2019(COVID-19)

Polarization-Insensitive All-Optical time-Division Demultiplexer Constructed with a Nonlinear Loop Interferometer

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光学学报 2003年第S1期23卷 589-590页

作者： t.k. Liang C.S. wong H.k. tsang C. Shu the Chinese University of Hong kong Department of Electronic Engineering Hong Kong ChinaThe Chinese University of Hong Kong Department of Electronic Engineering Hong Kong ChinaThe Chinese University of Hong Kong Department of Electronic Engineering Hong Kong ChinaThe Chinese University of Hong Kong Department of Electronic Engineering Hong Kong China

A polarization-insensitive 40-Gb/s time-division demultiplexer was demonstrated in a polarization-diversity loop configuration. the power penalty was measured to be 2.3 dB at a bit error rates of 10-9 for 10 Gb/s outp... 详细信息

关键词： OtDM et in Polarization-Insensitive All-Optical time-Division Demultiplexer Constructed with a Nonlinear Loop Interferometer UNI were FWHM BERt length of with

Binary ionic liquid electrolyte design for ultrahigh-energy density graphene-based supercapacitors

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Materials Reports(Energy) 2022年第2期2卷 58-67页

作者： Shao Ing wong Han Lin tianyi Ma Jaka Sunarso Basil t.wong Baohua Jia Centre for translational Atomaterials School of ScienceComputing and Engineering TechnologiesSwinburne University of TechnologyHawthornVictoria 3122Australia School of Science RMIT UniversityMelbourneVictoria 000Australia Research Centre for Sustainable technologies Faculty of EngineeringComputing and ScienceSwinburne University of TechnologyJalan Simpang Tiga93350 KuchingSarawakMalaysia

Although room temperature ionic liquids(ILs)have emerged as potential next-generation electrolytes for their wide electrochemical stability window(ESW),the trade-off between this window and viscosity has hindered their widespread use in energy storage ***,we present for the first time that such a trade-off can be balanced by mixing two ILs with the common anion([Ntf_(2)]^(-))but different cations([EMIM]^(+) and[N1114]^(+))***[EMIM]cation-based IL possesses low viscosity while the[N1114]cation-based IL exhibits wide *** the concentrations of each IL in the mixtures can result in different electrolyte properties,we demonstrate a systematic approach by exploring the properties of various concentration *** addition,the corresponding cell voltage of their resulting graphene supercapacitors(SCs)accompanied based on the interaction between the binary ionic liquid and the electrodes,and the associated electrochemical performance were studied to determine the optimum electrolyte system for the highest SC energy *** well-balanced viscosity/ESW trade-off is achieved in binary IL consisting 50 vol%[EMIM][Ntf_(2)]and 50 vol%[N1114][Ntf_(2)]as evident from the extraordinary electrode specific capacitance of 293.1 F g^(-1) and the ultrahigh SC energy density of 177 Wh kg^(-1),which approaches that of a lithium-ion battery.

关键词： Electrolyte Binary ionic liquid Maximum working voltage High capacitance High energy density Supercapacitor

A tV-Based Iterative Regularization Method for the Solutions of thermal Convection Problems

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Communications in Computational Physics 2013年第9期14卷 1120-1146页

作者： Eric t.Chung Jeff C.-F.wong Department of Mathematics Lady Shaw BuildingThe Chinese University of Hong KongShatinHong Kong

Linear/nonlinear and Stokes based-stabilizations for the filter equations for damping out primitive variable(PV)solutions corrupted by uniformly distributed randomnoises are numerically studied through the natural convection(NC)aswell as the mixed convection(MC)*** most recognizable filter-scheme is based on a combination of the negative Laplace equation multiplied with the selection of the spatial scale and a linear function in order to preserve the uniqueness of the filtered solution.A more complicated filter-scheme,based on a Stokes problem which couples a filtered velocity and a filtered(artificial)pressure(or Lagrange multiplier)in order to enforce the incompressibility constraint,is also *** and Stokes basedfilters via nested iterative(NI)filters and the consistent splitting scheme(CSS)are proposed for the NC/MC *** by the total-variation(tV)model of image diffusion,well preserved feature flow patterns from the corrupted NC/MC environment are obtained by tV-Stokes based-filters together with the *** experimental results show that our proposed algorithms are effective and efficient in eliminating the unwanted spurious oscillations and preserving the accuracy of thermal convective fluid flows.

关键词： Linear/nonlinear differential filter Stokes differential filters Leray-alpha model total-variation regularization

Patterns of in-hospital mortality and bleeding complications following PCI for very elderly patients： insights from the Dartmouth Dynamic Registry

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Journal of Geriatric Cardiology 2018年第2期15卷 131-136页

作者： Shawn X Li Hannah I Chaudry Jiyong Lee theodore B Curran Vishesh kumar kendrew k wong Bruce W Andrus James t DeVries Dartmouth Geisel School of Medicine Hanover NH USA Department of Internal Medicine Dartmouth-Hitcheock Medical Center Lebanon NH USA Section of Cardiovascular Medicine Dartmouth-Hitchcock Medical Center Lebanon NH USA

Background Very elderly patients （age 〉 85 years） are a rapidly increasing segment of the population. As a group, they experience high rates of in-hospital mortality and bleeding complications following percutaneous coronary intervention （PCI）. However, the relationship between bleeding and mortality in the very elderly is unknown. Methods Retrospective review was performed on 17,378 consecutive PCI procedures from 2000 to 2015 at Dartmouth-Hitchcock Medical Center. Incidence of bleeding during the index PCI admission （bleeding requiring transfusion, access site hematoma 〉 5 cm, pseudoaneurysm, and retroperitoneal bleed） and in-hospital mortality were reported for four age groups （〈 65 years, 65-74 years, 75-84 years, and ≥ 85 years）. the mortality of patients who suffered bleeding complications and those who did not was calculated and multivariate analysis was performed for in-hospital mortality. Lastly, known predictors of bleeding were compared between patients age 〈 85 years and age ≥85 years. Results Of 17,378 patients studied, 1019 （5.9%） experienced bleeding and 369 （2.1%） died in-hospital following PCI. Incidence of bleeding and in-hospital mortality increased monotonically with increasing age （mortality： 0.94%, 2.27%, 4.24% and 4.58%; bleeding： 3.96%, 6.62%, 10.68% and 13.99% for ages 〈 65, 65-4, 75-84 and ≥ 85 years, respectively）. On multivariate analysis, bleeding was associated with increased mortality for all age groups except patients age ≥85 years [odds ratio （95% CI）： age 〈 65 years, 3.65 （1.99-6.74）; age 65-74 years, 2.83 （1.62-4.94）; age 75-84 years, 3.86 （2.56-5.82）, age ≥ 85 years 1.39 （0.49-3.95）]. Conclusions Bleeding and mortality following PCI increase with increasing age. For the very elderly, despite high rates of bleeding, bleeding is no longer predictive of in-hospital mortality following PCI.

关键词： Complications In-hospital mortality Percutaneous coronary intervention the elderly

Intracellular signaling mechanisms regulating the activation of human eosinophils by the novel th2 cytokine IL-33:implications for allergic inflammation

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Cellular & Molecular Immunology 2010年第1期7卷 26-34页

作者： Joyce YS Chow Chun k wong Phyllis FY Cheung Christopher Wk Lam Department of Chemical Pathology The Chinese University of Hong KongPrince of Wales HospitalShatinNTHong KongChina Macao Institute for Applied Research in Medicine and Health Macao University of Science and Technology FoundationMacaoChina

the novel interleukin(IL)-1 family cytokine IL-33 has been shown to activate t helper 2(th2)lymphocytes,mast cells and basophils to produce an array of proinflammatory cytokines,as well as to mediate blood eosinophilia,IgE secretion and hypertrophy of airway epithelium in *** the present study,we characterized the activation of human eosinophils by IL-33,and investigated the underlying intracellular signaling ***-33 markedly enhanced eosinophil survival and upregulated cell surface expression of the adhesion molecule intercellular adhesion molecule(ICAM)-1 on eosinophils,but it suppressed that of ICAM-3 and *** addition,IL-33 mediates significant release of the proinflammatory cytokine IL-6 and the chemokines CXCL8 and *** found that IL33-mediated enhancement of survival,induction of adhesion molecules,and release of cytokines and chemokines were differentially regulated by activation of the nuclear factor(NF)-kB,p38 mitogen-activated protein kinase(MAPk)and extracellular signal-regulated kinase(ERk)***,we compared the above IL-33 activities with two structurally and functionally related cytokines,IL-1 B and ***-1β,but not IL-18,markedly upregulated cell surface expression of ***-1βand IL-18 also significantly enhanced eosinophil survival,and induced the release of IL-6 and chemokines CXCL8 and CCL2 via the activation of the NF-κB,p38 MAPk and ERk *** efects on the release of IL-6 were also observed in combined treatment withIL-1B,IL-18 and *** together,our findings provide insight into IL-33-mediated activation of eosinophils via differential intracellular signaling cascades in the immunopathogenesis of allergic inflammation.

关键词： allergy cytokines eosinophils signal transduction

High-speed high-resolution laser diode-based photoacoustic microscopy for in vivo microvasculature imaging

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Visual Computing for Industry,Biomedicine,and Art 2021年第1期4卷 1-6页

作者： Xiufeng Li Victor t C tsang Lei kang Yan Zhang terence t W wong translational and Advanced Bioimaging Laboratory Department of Chemical and Biological EngineeringHong Kong University of Science and TechnologyHong KongChina

Laser diodes(LDs)have been considered as cost-effective and compact excitation sources to overcome the requirement of costly and bulky pulsed laser sources that are commonly used in photoacoustic microscopy(PAM).However,the spatial resolution and/or imaging speed of previously reported LD-based PAM systems have not been optimized *** this paper,we developed a high-speed and high-resolution LD-based PAM system using a continuous wave LD,operating at a pulsed mode,with a repetition rate of 30 kHz,as an excitation source.A hybrid scanning mechanism that synchronizes a one-dimensional galvanometer mirror and a two-dimensional motorized stage is applied to achieve a fast imaging capability without signal averaging due to the high signal-to-noise *** optimizing the optical system,a high lateral resolution of 4.8μm has been *** vivo microvasculature imaging of a mouse ear has been demonstrated to show the high performance of our LD-based PAM system.

关键词： Photoacoustic microscopy Laser diode In vivo imaging Microvasculature imaging

tRIBOLOGICAL AND HIGH SPEED tURNING PERFORMANCE IN ti_(1-x)Al_(x)N COAtINGS PREPARED BY CLOSE-FIELD UNBALANCED MAGNEtRON SPUttERING

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 254-260页

作者： P.W.Shum M.Escursell t.H.wong k.Y.Li Z.F.Zhou Y.G.Shen Advanced Coatings Applied Research Laboratory(ACARL) Department of Manufacturi ng Engineering and Engineering ManagementCity University of Hong KongKowloonHong KongChina

titanium-aluminium-nitride(ti_(1-x)Al_(x)N)coatings were deposited by close-field un balanced magnetron sputtering on M42 steel substrates and WC-6wt%Co inserts at 450℃.the tribological behavior was analyzed by sliding against steel and WC-6wt%Co balls,while the turning performance was evaluated by a conventional tu rning machine at high cutting speeds without using *** the tribological tests,the formation of transfer layer and the variations of hardness of the co atings played an important role for sliding against steel *** the coating s sliding against WC-6wt%Co balls,the ti-Al-N coatings showed a similar frictio n coefficient,but the tiN coating exhibited a lower *** difference could be explained by the tri-oxidation wear *** the turning tests,a super ior cutting performance of the coating was found at x=0.45,which endured 38 min utes before the tool flank wear reached the maximum value of 0.3mm,whereas only 20 minutes were endured for the tiN *** excellent performance of the c oatings in the turning tests could be explained by the enhanced mechanical prope rties and oxidation/diffusion resistance of the coatings.

关键词： hardness ti-Al-N coating tribology turning test wear test