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EFFECTS OF MASS transfer ON THE THINNING AND RUPTURE OF A PLANE PARALLEL LIQUID FILM

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Chinese Journal of Chemical Engineering 1994年第3期2卷 33-49页

作者：李佟茗 Tianjin Univ Tianjin China

The effects of mass transfer and physical properties upon the thinning and rupture of adraining plane parallel film are *** equation is derived in which the thinning rate is afunction of bulk *** properties(surface tension,surface viscosities,and the variationof surface tension with surface concentration),intermolecular forces(London-van der Waals forcesand electrostatic double layer forces),adsorption and surface diffusion coefficients,bubble size andfilm *** estimation for the critical thickness at which a film rupture is carried out and thecoalescence time is obtained by integration to the critical thickness,The coalescence time is predictedas a function of bulk and surface properties,London-van der forces,adsorption and surfacediffusion coefficients,and bubble size.

关键词： bubble coalescence thin film drainage mass transfer effect on coalescence

URBAN TRANSIT ASSIGNMENT MODEL BASED ON AUGMENTED NETWORK WITH IN-VEHICLE CONGESTION AND transfer CONGESTION

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Journal of Systems Science and Systems Engineering 2011年第2期20卷 155-172页

作者： Bingfeng SI Ming ZHONG Xiaobao YANG Ziyou GAO MOE Key Laboratory for Urban Transportation Complex Systems Theory and Technology Beijing Jiaotong University Beijing 100044 China Department of Civil Engineering University of New Brunswick Fredericton New Brunswick E3B 5A3 Canada

This paper presents an augmented network model to represent urban transit *** such network model,the urban transit assignment problem can be easily modeled like a generalized traffic ***,the feasible route in such augmented transit network is then defined in accordance with the passengers＇ *** passengers＇ travel costs including walking time,waiting time,in-vehicle time and transfer time are formulated while the congestions at stations and the congestions in transit vehicles are all taken into *** the base of these,an equilibrium model for urban transit assignment problem is presented and an improved shortest path method based algorithm is also proposed to solve ***,a numerical example is provided to illustrate our approach.

关键词： Transit assignment augmented network congestion transfer algorithm

Real-Time Avatar Pose transfer and Motion Generation Using Locally Encoded Laplacian Offsets

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Journal of Computer Science & Technology 2019年第2期34卷 256-271页

作者： Masoud Zadghorban Lifkooee Celong Liu Yongqing Liang Yimin Zhu Xin Li Department of Electrical and Computer Engineering Louisiana State University Baton Rouge 70803 U.S.A. Department of Construction Management Louisiana State University Baton Rouge 70803 U.S.A.

We propose a human avatar representation scheme based on intrinsic coordinates,which are invariant to isometry and insensitive to human pose changes,and an efficient pose transfer algorithm that can utilize this representation to reconstruct a human body geometry following a given *** a pose transfer algorithm can be used to control the movement of an avatar model in virtual reality environments following a user's motion in real *** proposed algorithm consists of three main ***,we recognize the user's pose and select a template model from the database who has a similar pose;then,the intrinsic Laplacian offsets encoded in local coordinates are used to reconstruct the human body geometry following the template pose;finally,the morphing between the two poses is generated using a linear *** perform experiments to evaluate the accuracy and efficiency of our *** believe our proposed system is a promising human modeling tool that can be used in general virtual reality applications.

关键词： human body pose transfer local intrinsic coordinates avatar control in virtual reality

The heat transfer optimization of conical fin by shape modification

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Chinese Journal of Chemical Engineering 2016年第8期24卷 972-978页

作者： Jiansheng Wang Xiao Wang Key Laboratory of Efficient Utilization of Low and Medium Grade Energy MOE School of Mechanical Engineering Tianjin University

In present work, a stepping optimization algorithm is proposed for the geometric optimization of conical fin, and the heat transfer rate of the fin is treated as the objective function in the optimization algorithm. The conical fin is divided into finite elements which have different generatrix slopes, and the geometry of the conical fin is finally determined by ensuring that every divided element can maintain the maximum heat transfer rate. Based on the actual condition of every element of the fin, the heat conduction equation is solved step by step. The present result shows that the optimized conical fin has more heat transfer quantity and higher fin efficiency compared with those of some typical fins. Furthermore, the theoretical feasibility and the error analysis of present optimization algorithm have been performed as well.

关键词： Fin Optimization Heat transfer Stepping optimization algorithm

Highly-sensitive wafer-scale transfer-free graphene MEMS condenser microphones

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Microsystems & Nanoengineering 2024年第1期10卷 267-275页

作者： Roberto Pezone Sebastian Anzinger Gabriele Baglioni Hutomo Suryo Wasisto Pasqualina M.Sarro Peter G.Steeneken Sten Vollebregt Laboratory of Electronic Components Technology and Materials(ECTM)Department of MicroelectronicsDelft University of TechnologyDelftThe Netherlands Infineon Technologies AG Am Campeon 1-15Neubiberg 85579Germany Kavli Institue of Nanoscience Department of Quantum NanoscienceDelft University of TechnologyDelftthe Netherlands Department of Precision and Microsystems Engineering(PME) Delft University of TechnologyDelftThe Netherlands

Since the performance of micro-electro-mechanical system(MEMS)-based microphones is approaching fundamental physical,design,and material limits,it has become challenging to improve *** works have demonstrated graphene’s suitability as a microphone *** potential for achieving smaller,more sensitive,and scalable onchip MEMS microphones is yet to be *** address large graphene sizes,graphene-polymer heterostructures have been proposed,but they compromise performance due to added polymer mass and *** work demonstrates the first wafer-scale integrated MEMS condenser microphones with diameters of 2R=220-320μm,thickness of 7 nm multi-layer graphene,that is suspended over a back-plate with a residual gap of 5μ*** microphones are manufactured with MEMS compatible wafer-scale technologies without any transfer steps or polymer layers that are more prone to contaminate and wrinkle the *** designs,all electrically integrated are fabricated and characterized allowing us to study the effects of the introduction of a back-plate for capacitive *** devices show high mechanical compliances C_(m)=0.081-1.07μmPa^(−1)(10-100×higher than the silicon reported in the state-of-the-art diaphragms)and pull-in voltages in the range of 2-9.5 *** addition,to validate the proof of concept,we have electrically characterized the graphene microphone when subjected to sound *** estimated sensitivity of S_(1kHz)=24.3-321 mV Pa^(−1)for a V_(bias)=1.5 V was determined,which is 1.9-25.5×higher than of state-of-the-art microphone devices while having a~9×smaller area.

关键词： transfer plate approaching

Recent progress of energy transfer and luminescence intensity boosting mechanism in Nd3+-sensitized upconversion nanoparticles

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Journal of Rare Earths 2019年第8期37卷 791-805,I0001页

作者： Solomon Tiruneh Dibaba Xiaoqian Ge Wei Ren Lining Sun Physics Department and International Centre for Quantum and Molecular StructuresShanghai UniversityShanghai 200444China Research Center of Nano Science and Technology and School of Material Science and EngineeringShanghai UniversityShanghai 200444China

Rare earth doped upconversion nanoparticles can be considered as the spice of research in the field of luminescence nanomaterials due to their unique optical properties such as near-infrared *** works have been reported about biomedical applications of 980 nm excited and Yb^3+-sensitized upconversion ***,980 nm excitation wavelength overlaps with the absorption band of water molecules in the biological environment,leading to overheating effect that can induce thermal damages of normal cells and ***,Nd^3+-sensitized upconversion nanoparticles which can be excited with 808 nm has been widely investigated as alternative nanoparticles that can surmount this issue of overheating *** though Nd^3+-sensitized upconversion nanoparticles can reduce the overheating effect by 20 fold as compared to Yb^3+-sensitized counterpart,there are several factors that reduce the upconversion luminescence *** this review article,photon energy harvesting and transferring mechanisms in Nd^3+,Yb^3+and emitter ions co-doped upconversion nanoparticles under 808 nm excitation are briefly *** that affect upconversion luminescence intensity and quantum yield of Nd^3+-sensitized upconversion nanoparticles are also ***,some of the important strategies that have been recently utilized to boost upconversion luminescence intensity of Nd^3+sensitized upco nversion nanoparticles are tho roughly ***,the future challenges in the area and our perspectives are in sight.

关键词： Rare earth Upconversion nanoparticles Nd^3+-sensitized Energy transfer

Universally composable oblivious transfer from ideal lattice

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Frontiers of Computer Science 2019年第4期13卷 879-906页

作者： Momeng LIU Yupu HU State Key Laboratory of Integrated Service Networks Xidian University Xi'an 710071 China

As a fundamental cryptographic primitive, oblivious transfer (OT) is developed for the sake of efficient usability and combinational feasibility. However, most OT protocols are built upon some quantum non-immune cryptosystems by assuming the hardness of discrete logarithm or factoring problem, whose security will break down directly in the quantum setting. Therefore, as a subarea of postquantum cryptography, lattice-based cryptography is viewed as a promising alternative and cornerstone to support for building post-quantum protocols since it enjoys some attractive properties, such as provable security against quantum adversaries and lower asymptotic complexity. In this paper, we first build an efficient 1-out-of-2 OT protocol upon the hardness of ring learning with errors (RLWE) problem, which is at least as hard as some worst-case ideal lattice problems. We show that this 1-out-of-2 OT protocol can be universally composable and secure against static corruptions in the random oracle model. Then we extend it to a general case, i.e., 1-out-of-N OT with achieving the same level of security. Furthermore, on the basis of the above OT structure, we obtain two improved OT protocols using two improved lattice-based key exchange protocols (respectively relying on the RLWE problem and learning with errors (LWE) problem, and both achieving better efficiency by removing the Gaussian sampling for saving cost) as building blocks. To show that our proposed OT protocol indeed achieves comparable security and efficiency, we make a comparison with another two lattice-based OT protocols in the end of the paper. With concerning on the potential threat from quantum computing and expecting on the practical use of OT with high efficiency, an efficient post-quantum OT protocol is pressing needed. As shown in this paper, our proposed OT protocols may be considered as post-quantum OT candidates since they can both preserve provable security relying on lattice problems and enjoy practical eff

关键词： oblivious transfer universally composability lattice-based cryptography learning with errors ring learning with errors random oracle model

HYDRODYNAMICS AND MASS transfer IN A NEW TYPE(FG)STACK PACKED EXTRACTION COLUMN

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Chinese Journal of Chemical Engineering 1996年第4期4卷 63-69页

作者：朱慎林骆广生张宝清清华大学化学工程系北京

Hydrodynamics and mass transfer experiments were carried out in a 0.1m diameter extraction column with a new type (FG) stack packing developed recently in our *** working systems used were n-Butano1/Succinic acid/water with low interfacial tension of 1.50×10-3N·m-1 and 30% TBP (Kerosene)/Acetic acid/water with interfacial tension of 10.0×10-3N· m-1. Experimental results obtained indicated that (FG) stack packed extraction column was proved to possess high throughput capacity and excellent mass transfer efficiency. Replacing rotary discs with FG packings in a lube furfural extraction tower was quite success with significant economical benefits being claimed.

关键词： extraction column stack packing throughput capacity mass transfer

Improving the efficiency of magnetic coupling energy transfer byetching fractal patterns in the shielding metals

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Frontiers of Information Technology & Electronic Engineering 2016年第1期17卷 74-82页

作者： Qing-feng LI Shao-bo CHE Wei-ming WANG Hong-wei HAO Lu-ming LI School of Aerospace Tsinghua University Beijing 100084 China National Engineering Laboratory for Neuromodulation Beijing 100084 China Center of Epilepsy Beijing Institute for Brain Disorders Beijing 100084 China

Thin metal sheets are often located in the coupling paths of magnetic coupling energy transfer(MCET) systems. Eddy currents in the metals reduce the energy transfer efficiency and can even present safety risks. This paper describes the use of etched fractal patterns in the metals to suppress the eddy currents and improve the efficiency. Simulation and experimental results show that this approach is very effective. The fractal patterns should satisfy three features, namely, breaking the metal edge, etching in the high-intensity magnetic field region, and etching through the metal in the thickness direction. Different fractal patterns lead to different results. By altering the eddy current distribution, the fractal pattern slots reduce the eddy current losses when the metals show resistance effects and suppress the induced magnetic field in the metals when the metals show inductance effects. Fractal pattern slots in multilayer high conductivity metals(e.g., Cu) reduce the induced magnetic field intensity significantly. Furthermore, transfer power, transfer efficiency, receiving efficiency, and eddy current losses all increase with the increase of the number of etched layers. These results can benefit MCET by efficient energy transfer and safe use in metal shielded equipment.

关键词： Fractal pattern,Metal-layer-shield,Eddy current,Magnetic coupling energy transfer