检索结果-南通市图书馆

A new stationary droplet evaporation model and its validation

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2017年第4期30卷 1407-1416页

作者： Fang WANG jie yao Shaofeng YANG Rui LIU jie JIN Aero-engine Numerical Simulation Research Center School of Energy and Power Engineering Beihang University Beijing100083 China Co-Innovation Center for Advanced Aero-Engine Beijing 100083 China

The liquid droplet evaporation character is important for not only combustion chamber design process but also high-accuracy spray combustion simulation. In this paper, the suspended droplets＇ evaporation character was measured in a quiescent high-temperature environment by micro high-speed camera system. The gasoline and kerosene experimental results are consistent with the reference data. Methanol, common kerosene and aviation kerosene droplet evaporation characteristics, as well as their evaporation rate changing with temperature, were obtained. The evaporation rate experimental data were compared with the prediction result of Ranz-Marshall boiling temperature model（RMB）, Ranz-Marshall low-temperature model（RML）, drift flux model（DFM）, mass analogy model（MAM）, and stagnant film model（SFM）. The disparity between the experimental data and the model prediction results was mainly caused by the neglect of the natural convection effect, which was never introduced into the droplet evaporation concept. A new droplet evaporation model with consideration of natural convection buoyancy force effect was proposed in this paper. Under the experimental conditions in this paper, the calculation results of the new droplet evaporation model were agreed with the experimental data for kerosene, methanol and other fuels, with less than 20% relative deviations. The relative deviations between the new evaporation model predictions for kerosene and the experimental data from the references were within 10%.

关键词： Droplet Evaporation model Evaporation rate Kerosene Natural convection Thick exchange layer theory

Applying Deep Learning to Individual and Community Health Monitoring Data:A Survey

在线全文

学校读者我要写书评

暂无评论

International Journal of Automation and computing 2018年第6期15卷 643-655页

作者： Zhen-jie yao jie Bi Yi-Xin Chen Beijing Advanced Innovation Center for Future Internet Technology Beijing University of Technology Department of Computer Science and Engineering Washington University in St.Louis

In the recent years, deep learning models have addressed many problems in various fields. Meanwhile, technology development has spawned the big data in healthcare rapidly. Nowadays, application of deep learning to solve the problems in healthcare is a hot research direction. This paper introduces the application of deep learning in healthcare extensively. We focus on 7 application areas of deep learning, which are electronic health records （EHR）, electrocardiography （ECG）, electroencephalogram （EEG）, community healthcare, data from wearable devices, drug analysis and genomics analysis. The scope of this paper does not cover medical image processing since other researchers have already substantially reviewed it. In addition, we analyze the merits and drawbacks of the existing works, analyze the existing challenges, and discuss future trends.

关键词： Deep learning healthcare electronic health records (EHR) neural networks survey.

Super-Resolution Imaging by using a Metallic Rod Array in the Near Infrared Region

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2012年第4期29卷 210-212页

作者： yao jie YE Yong-Hong College of Physics Science and Technology Nanjing Normal UniversityNanjing 210046

An array of metallic rods can transport details below the diffraction limit of an object from the front face to the back *** super-resolution imaging system has been studied in the microwave,mid-infrared and optical *** investigate its performance in the near infrared (1550nm) *** simulations show that the near-field components of dipole sources are transferred by the excitation and propagation of the surface plasmon mode of the *** appropriate length of rods is determined by the excited surface plasmon *** spatial resolution is greatly affected by the loss of metal.

关键词： resolution Infrared details

Catalytic Systems Containing p-Toluenesulfonic Acid for the Coupling Reaction of Formaldehyde and Methyl Formate

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2007年第3期16卷 286-292页

作者： Kebing Wang jie yao Yue Wang Gongying Wang Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 Sichuan China Graduate School of Chinese Academy of Sciences Beijing 100039 China

The coupling reaction of formaldehyde （FA） and methyl formate （MF） to form methyl glycolate （MG） and methyl methoxy acetate （MMAc）, catalyzed by p-toluenesulfonic acid （p-TsOH） as well as assisted by different kinds of solvents or Ni-containing compounds, had been investigated. The results showed that when the reaction was carried out at 140 ℃, with a molar ratio of FA to MF of 0.65 ： 1, molar fraction of p-TsOH to total feedstock of 11.0%, and reaction time of 3 h, the yield of MG and MMAc was 31.1% and 17.1%, respectively, p-TsOH catalyzed the coupling reaction by means of the synergistic catalysis of protonic acidity and soft basicity. Adding extra solvents to the reaction system was unfavorable for the reaction. The composite catalytic system consisting of p-TsOH and NiX2 （X=Cl, Br, I） exhibited a high catalytic performance for the coupling reaction, and NiX2 acted as a promoter in the reaction, whose promotion for the catalysis increased in the following order： NiCl2〈NiBr2〈NiI2. The present system is less corrosive when compared with the previous system, in which strong inorganic liquid acids were used as catalysts.

关键词： formaldehyde methyl formate methyl glycolate methyl methoxy acetate p-toluenesulfonicacid

Statistical mechanics of a nonequilibrium steady-state classical particle system driven by a constant external force

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2020年第11期72卷 104-108页

作者： jie yao Yanting Wang CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of Sciences55 East Zhongguancun RoadPO Box 2735Beijing100190 China School of Physical Sciences University of Chinese Academy of Sciences19A Yuquan RoadBeijing 100049China

A classical particle system coupled with a thermostat driven by an external constant force reaches its steady state when the ensemble-averaged drift velocity does not vary with *** this work,the statistical mechanics of such a system is derived solely based on the equiprobability and ergodicity principles,free from any conclusions drawn on equilibrium statistical mechanics or local equilibrium *** momentum space distribution is determined by a random walk argument,and the position space distribution is determined by employing the equiprobability and ergodicity *** expressions for energy,entropy,free energy,and pressures are then deduced,and the relation among external force,drift velocity,and temperature is also ***,the relaxation towards its equilibrium is found to be an exponentially decaying process obeying the minimum entropy production theorem.

关键词： nonequilibrium steady state constant external force dissipation statistical mechanics

Gene positioning and genome function

在线全文

学校读者我要写书评

暂无评论

Frontiers in Biology 2014年第4期9卷 255-268页

作者： Nidhi VISHNO jie yao Department of Cell Biology Yale University School of Medicine New Haven CT 06520 USA

The eukaryotic genome is packaged as chromatin within the three-dimensional nuclear space. Decades of cytological studies have revealed that chromosomes and genes are non-randomly localized within the nucleus and such organizations have important roles on genome function. However, several fundamental questions remain to be resolved. For example, what is required for the preferential localization ofa gene to a nuclear landmark？ What is the mechanism underlying gene repositioning in the nucleus？ How does subnuclear gene positioning regulate gene transcription？ Recent studies have revealed that several factors such as DNA sequence composition, specific regulatory sequences, epigenetic modifications, chromatin remodelers, post-transcriptional regulators and nuclear architectural proteins can influence chromatin dynamics and gene positioning in a gene-specific manner among organisms from yeast to human. In this review, we discuss some recent findings as well as experimental tools to investigate subnuclear gene positioning and to explore its implications in genome functions.

关键词： nucleus transcription gene positioning epigenetics nuclear lamina chromatin

A Mesh Size Scaling Law with Reynolds Number for Large Eddy Simulation in Channel Flow

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 Applied Mathematics and Mechanics 2022年第6期14卷 1535-1566页

作者： jie yao C.J.Teo Department of Mechanical Engineering National University of Singapore9 Engineering Drive 1Singapore 117575

In this paper,a scaling law relating the mesh size to the Reynolds number was proposed to ensure consistent results for large eddy simulation(LES)as the Reynolds number was *** grid size scaling law was developed by analyzing the lengthscale of the turbulent motion by using DNS data from the *** wall-resolving LES was then applied to a plane channel flow to validate the scaling *** scaling law was tested at different Reynolds numbers(Ret=395,590 and 1000),and showed good results compared to direct numerical simulation(DNS)in terms of mean flow and various turbulent *** velocity spectra analysis shows the evidence of the Kolmogorov–5/3 inertial subrange and verifies that the current LES can resolve the bulk of the turbulent kinetic energy by satisfying the grid scaling ***,the near-wall turbulent flow structures can also be well *** accurate predictions can thus be obtained for flows at even higher Reynolds numbers with significantly lower computational costs compared to DNS by applying the mesh scaling law.

关键词： Large eddy simulation(LES) channel flow turbulent flow mesh size scaling law.

Realization of Two-Qutrit Quantum Gates with Control Pulses

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2009年第4期51卷 653-658页

作者： ZHANG jie DI yao-Min WEI Hai-Rui School of Physics ＆ Electronic Engineering Xuzhou Normal University Xuzhou 221116 China

We investigate the realization of 2-qutrit logic gate in a bipartite 3-level system with qusi-Ising interaction. On the basis of Caftan decomposition of matrices, the unitary matrices of 2-qutrit are factorized into products of a series of realizable matrices. It is equivalent to exerting a certain control field on the system, and the control goal is usually gained by a sequence of control pulses. The general discussion on the realization of 2-qutrit logic gate is made first, and then the realization of the ternary SWAP gate and the ternary √SWAP gate are discussed specifically, and the sequences of control pulses and drift processes implementing these gates are given.

关键词： Caftan decomposition 2-qutrit system ternary SWAP gate ternary √SWAP gate

Scattering of S0 Lamb Mode from a Blind Hole in a Plate Using Mindlin/Mindlin Plate Theory

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2014年第3期31卷 86-90页

作者： ZHANG Hai-Yan yao jie-Cong MA Shi-Wei School of Communication and Information Engineering Key Laboratory of Specialty Fiber Optics and Optical Access Networks Shanghai University Shanghai 200072 Shanghai Key Laboratory of Power Station Automation Technology School of Mechatronic Engineering and Automation Shanghai University Shanghai 200072

An analytical model of Lamb wave scattering from a circular blind hole in isotropic plates is presented using the Mindlin plate theory for describing in-plane and flexural wave modes simultaneously. The model makes use of the wave function expansion technique and the boundary conditions at the hole edge to evaluate the scattered far fields of three fundamental guided wave modes. Comparisons are made to existing approximate models using Poisson/Kirchhoff theory and Poisson/Mindlin theory and a 3D model using the exact 3D equations. The results reveal that the present model is more consistent with the exact 3D model at higher frequencies than existing approximate models.

关键词： LAMB waves RESEARCH SCATTERING (Physics) MINDLIN theory EQUATIONS PHYSICS research