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Chinese Journal of Chemical Engineering 2021年第4期34卷 360-367页

作者： Muralikrishna Boni s.srinivasa Rao G.Naga srinivasulu Department of Mechanical Engineering National Institute of Technology WarangalWarangalTelanganaIndia

Passive Direct methanol fuel cells(DMFC)are more suitable for charging small capacity electronic *** passive DMFC,the fuel and oxidant are supplied by diffusion and natural convection process on the anode and cathode sides *** collectors(CC)play a vital importance in fuel cell *** paper presents the combined impact of perforated and wire mesh current collectors(WMCC)on passive DMFC *** types of open ratios of perforated current collectors(PCC),such as 45.40%,55.40%and 63.40%and two types of wire mesh current collectors with open ratios of 38.70%and 45.40%were chosen for the experimental work.A combination of TaguchiL9 rule is considered.A combination of three PCC and two WMCC on both anode and cathode was *** concentration was varied from 1 mol·L^(-1)-5 mol·L^(-1)for nine combinations of PCC and *** the experimental results,it is noticed that the combination of PCC and WMCC with an open ratio of 55.40%and 38.70%incorporated passive DMFC produced peak power density at 5 mol·L^(-1)of methanol *** passive DMFC performance was evaluated in terms of maximum power density and maximum current *** combined current collectors of PCC and WMCC open ratios of 55.40%+38.70%have more stable voltage than single PCC of open ratio 63.40%at 4 mol·L^(-1)of methanol concentration.

关键词： Passive DMFC Perforated current collector Wire mesh current collector Methanol concentration Fuel cell performance

Object removal from complex videos using a few annotations

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Computational Visual Media 2019年第3期5卷 267-291页

作者： Thuc Trinh Le Andrés Almansa Yann Gousseau simon Masnou LTCI T′el′ecom ParisTechUniversit′e Paris-Saclay75013 ParisFrance MAP5 CNRS&Universit′e Paris Descartes75006 ParisFrance Univ Lyon Universit′e Claude Bernard Lyon 1CNRS UMR 5208Institut Camille Jordan69622 VilleurbanneFrance

We present a system for the removal of objects from videos. As input, the system only needs a user to draw a few strokes on the first frame, roughly delimiting the objects to be removed. To the best of our knowledge, this is the first system allowing the semi-automatic removal of objects from videos with complex backgrounds. The key steps of our system are the following: after initialization, segmentation masks are first refined and then automatically propagated through the video. Missing regions are then synthesized using video inpainting techniques. Our system can deal with multiple, possibly crossing objects, with complex motions, and with dynamic textures. This results in a computational tool that can alleviate tedious manual operations for editing high-quality videos.

关键词： object removal object segmentation object tracking video inpainting video completion

Deciphering deformation mechanisms of hierarchical dual-phase CrCoNi coatings

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Journal of Materials science & Technology 2020年第4期39卷 7-13页

作者： s.J.Tsianikas Y.Chen Z.Xie school of Mechanical Engineering The University of AdelaideAdelaideSA5005Australia Centre for Advanced Thin Film Materials and Device Faculty of Materials and EnergySouthwest UniversityChongqing400715China school of Engineering Edith Cowan UniversityWA6027Australia

Hierarchical Cr Co Ni medium entropy alloy(MEA)thin films with a dual-phase face-centred cubic(FCC)and hexagonal closed-packed(HCP)nanostructure were prepared on M2 steel substrates by closed field unbalanced magnetron *** tests show an ultra-high hardness of 9.5 GPa,attributable to large amounts of innate planar defects(i.e.,growth twins and stacking faults)impeding dislocation motion in the coatings.A deep analysis of undeformed and post-mortem samples reveals grain refinement as the dominant deformation mechanism in FCC dominated regions,while phase transformation and shear banding played major roles in regions occupied by HCP *** grain refinement was facilitated by twin/matrix lamellae,with dislocations piling up and arranging into interconnecting grain *** shear banding was accelerated by innate planar defects in the HCP phase due to a lack of slip *** particular interest is the observation of HCP→FCC phase transformation,which was catalysed by deformation-induced grain reorientation with innate stacking faults acting as embryos to grow the FCC *** results of this work suggest that multiple deformation pathways could be activated in Cr Co Ni coatings with assistance of growth defects,thereby imparting these technically important coatings appreciable ductility.

关键词： Medium entropy alloys sputter deposition Grain refinement shear banding Phase transformation

Observation of an EPIR Effect in Nd_(1-x)sr_xMnO_3 Ceramics with secondary Phases

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Journal of Materials science & Technology 2013年第8期29卷 737-741页

作者： s.s.Chen X.J.Luo D.W.shi H.Li C.P.Yang school of Mathematics and Physics Hubei Polytechnic University Faculty of Physics and Electronic Technology Hubei University

Nd1-xsrxMnO3 （x ： 0.3, 0.5） ceramics containing a secondary phase are synthesized by high-energy ball milling and post heat-treatment method. The 4-wire and 2-wire measuring modes are used to investigate the transport character of the grain/phase boundary （inner interface） and electrode-bulk interface （outer interface）, respectively, and the results indicate that there is a similar nonlinear I-V behaviour for both of the inner and outer interfaces, however, the electric pulse induced resistance change （EPIR） effect can only be observed at the outer interface.

关键词： Electric pulse induced resistance change (EPIR) space charge layer Nonlinearity Manganite High-energy ball milling

Effect of wall temperature modulation on the heat transfer characteristics of droplet-train flow inside a rectangular microchannel

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Chinese Journal of Chemical Engineering 2020年第3期28卷 685-697页

作者： Vivekanand s.V.B.,Raju V.R.K. Department of Mechanical Engineering National Institute of TechnologyWarangalTelangana 506004India

The numerical studies of water–oil two-phase slug flow inside a two-dimensional vertical microchannel subjected to modulated wall temperature boundary conditions have been discussed in the present *** researchers have contributed their efforts in exploring the characteristics of Taylor flows inside microchannel under constant wall heat flux or isothermal wall ***,there is no study available in the literature which discusses the impact of modulated thermal wall boundary conditions on the heat transfer behavior of slug flows inside ***,to bridge this gap,an effort has been made to understand the heat transfer characteristics of the flow under sinusoidal wall temperature ***,a single phase flow and heat transfer study was performed in microchannels,and the results of the fully developed velocity profile and heat transfer rate were validated with benchmark analytical *** an optimal selection of the combination of sinusoidal thermal wall boundary conditions has been made for the two-phase slug flow ***,the effects of amplitude(0 bεb 0.03)and frequency(0 bωb 750πrad·s-1)of the sinusoidal wall temperature profile on the heat transfer have been studied using the optimal combination of the wall boundary *** results of the numerical study using modulated temperature conditions on channel walls showed a significant improvement in the heat transfer over liquid-only flow by approximately 50%as well as over two-phase flow without wall temperature *** non-dimensional temperature contours obtained for different cases of temperature modulation clearly explain the root cause of such improvement in the heat ***,the results based on the hydrodynamics of the flow have also been reported in terms of variation of droplet shapes and film *** influence of Capillary number on the film thickness as well as heat transfer rates has also been *** addition,the measured fil

关键词： Heat transfer Microchannel Modulation surface tension Taylor flow

Mitigation of the blast load effects on a building structure using newly composite structural configurations

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Defence Technology（防务技术） 2021年第1期17卷 75-84页

作者： Ahmed K.Taha M.s.Zahran Zhengguo Gao school of Transportation science and Engineering Beihang University(Beijing University of Aeronautics and Astronautics)Beijing100191PR China Department of Civil Engineering Military Technical CollegeEgypt

In this study,a nonlinear three-dimensional hydrocode numerical simulation was carried out using AUTODYN-3D to investigate the effect of blasting of a high explosive material(TNT)against several configurations of the composite *** numerical models were carried out to study the effect of varying the thickness of the walls and the effect of adding an air layer or aluminum foam layer inside two layers of concrete in mitigating the effect of blast waves on the structure *** results showed that increasing the thickness of walls has a good effect on mitigating the effect of blast *** a layer of air was added,the effect of blast waves was exaggerated,while when a layer of aluminum foam was added the blast wave effects were mitigated with a reasonable percentage.

关键词： Concrete structures Blast waves Numerical simulation TNT

Importance of Touch in the Design of Pleasurable Products and Experiences

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Journal of Donghua University(English Edition) 2004年第3期21卷 130-133页

作者： Nicolas Bouché sébastien Crochemore Decathlon Design Center 59665 Villeneuve d' Ascq-FRANCERenault S.A.S 2 52 78288 Guyancourt-France

Today, the act of purchase is more and more irrational. Customers’ choices are based on emotional and multisensorial features, particularly on touch, which is the most emotional sense. Then it is essential in the design process to work on shapes, materials, textures to make users living pleasant experiences in all contact areas of the product. It’s also essential to consider the dynamic aspect of touch to follow the body and generate pleasant tactile effects. Finally, how can we introduce touch in the design process considering companies’ know-how, culture and subjectivity of each actor of new product creation?

关键词： Design of contact areas Touch physiology Touch psychology Design for senses Touch description Design of clothes Body fitting

Hybrid nanomaterial flow and heat transport in a stretchable convergent/divergent channel:a Darcy-Forchheimer model

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Applied Mathematics and Mechanics(English Edition) 2020年第5期41卷 699-710页

作者： G.K.RAMEsH s.A.sHEHZAD I.TLILI Department of Mathematics K.L.E Society’s J.T.CollegeGadag 582101KarnatakaIndia Department of Mathematics COMSATS University IslamabadSahiwal 57000Pakistan Department for Management of science and Technology Development Ton Duc Thang UniversityHo Chi Minh City 758307Vietnam Faculty of Applied sciences Ton Duc Thang UniversityHo Chi Minh City 758307Vietnam

The flow behavior in non-parallel walls is an important factor of any physical model including cavity flow and canals, which is applicable for diverging/converging channel. The present communication explains that the flow of the hybrid nanomaterial subjected to the convergent/divergent channel has non-parallel walls. It is assumed that the hybrid nanomaterial movement is in the porous region. A Darcy-Forchheimer medium of porosity is considered to interpret the porosity features. A useful similarity function is adopted to get the strong ordinary coupled equations. Numerical solutions are achieved through the Runge-Kutta-Fehlberg(RKF) fourth-fifth order method, and they are validated with the existing results. Physical nature of the involving constraints is reported with the help of plots. It is explored that the velocity of divergent channel decreases, and convergent channel enhances for the higher solid volume faction. Further, the presence of inertia coefficient and porosity parameter amplifies the velocity at the wall.

关键词： hybrid nanoliquid channel Darcy-Forchheimer flow stretching wall numerical solution

Thermal Properties of Ni–Cr–si–B–Fe Based Interlayer Material and Its Application in TLP Bonding of IN 718 superalloy

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Acta Metallurgica sinica(English Letters) 2020年第12期33卷 1666-1680页

作者： U.K.Tarai P.s.Robi sukhomay Pal Department of Mechanical Engineering IIT GuwahatiGuwahati 781039India

A new Ni–Cr–si–B–Fe fi ller material is prepared for transient liquid-phase(TLP)bonding of Inconel 718 superalloy by mechanical alloying *** melting temperature range of the fi ller material and its activation energy of melting are determined by diff erential scanning calorimetry *** activation energy and melting temperature of the alloy powder decrease with increasing milling *** 718 alloy was joined via TLP by using the newly developed fi ller *** eff ect of TLP bonding temperature and time on microstructural evolution and mechanical properties of the joint was *** distinct microstructural regions were observed in the bonding area:isothermal solidifi cation zone consisting of a single-phase solid solution,diff usion aff ected zone consisting of extensive diff usion-induced precipitates of metallic boride,and unaff ected base *** ultimate shear strength and microhardness of the TLP-bonded joint increase with bonding time and temperature.

关键词： Transient liquid-phase(TLP)bonding Kissinger plot Mechanical alloying Inconel 718

A dive into spectral inference networks: improved algorithms for self-supervised learning of continuous spectral representations

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Applied Mathematics and Mechanics(English Edition) 2023年第7期44卷 1199-1224页

作者： J.WU s.F.WANG P.PERDIKARIs Graduate Group in Applied Mathematics and Computational science University of Pennsylvania PhiladelphiaPA 19104U.S.A. Department of Mechanical Engineering and Applied Mechanics University of Pennsylvania PhiladelphiaPA 19104U.S.A.

We propose a self-supervising learning framework for finding the dominant eigenfunction-eigenvalue pairs of linear and self-adjoint *** represent target eigenfunctions with coordinate-based neural networks and employ the Fourier positional encodings to enable the approximation of high-frequency *** formulate a self-supervised training objective for spectral learning and propose a novel regularization mechanism to ensure that the network finds the exact eigenfunctions instead of a space spanned by the ***,we investigate the effect of weight normalization as a mechanism to alleviate the risk of recovering linear dependent modes,allowing us to accurately recover a large number of *** effectiveness of our methods is demonstrated across a collection of representative benchmarks including both local and non-local diffusion operators,as well as high-dimensional time-series data from a video *** results indicate that the present algorithm can outperform competing approaches in terms of both approximation accuracy and computational cost.

关键词： spectral learning partial differential equation(PDE) neural network slow features analysis