The ripple effect induced by uncontrollable Zn deposition is considered as the Achilles heel for developing high-performance aqueous Zn-ion batteries.For this problem,this work reports a design concept of 3D artificia...The ripple effect induced by uncontrollable Zn deposition is considered as the Achilles heel for developing high-performance aqueous Zn-ion batteries.For this problem,this work reports a design concept of 3D artificial array interface engineering to achieve volume stress elimination,preferred orientation growth and dendrite-free stable Zn metal anode.The mechanism of MXene array interface on modulating the growth kinetics and deposition behavior of Zn atoms were firstly disclosed on the multi-scale level,including the in-situ optical microscopy and transient simulation at the mesoscopic scale,in-situ Raman spectroscopy and in-situ X-ray diffraction at the microscopic scale,as well as density functional theory calculation at the atomic scale.As indicated by the electrochemical performance tests,such engineered electrode exhibits the comprehensive enhancements not only in the resistance of corrosion and hydrogen evolution,but also the rate capability and cyclic stability.High-rate performance(20 mA cm^(-2))and durable cycle lifespan(1350 h at 0.5 mA cm^(-2),1500 h at 1 mA cm^(-2)and 800 h at 5 mA cm^(-2))can be realized.Moreover,the improvement of rate capability(214.1 mAh g^(-1)obtained at 10 A g^(-1))and cyclic stability also can be demonstrated in the case of 3D MXene array@Zn/VO2battery.Beyond the previous 2D closed interface engineering,this research offers a unique 3D open array interface engineering to stabilize Zn metal anode,the controllable Zn deposition mechanism revealed is also expected to deepen the fundamental of rechargeable batteries including but not limited to aqueous Zn metal batteries.展开更多
BP( Back Propagation) neural network and PSO( Particle Swarm Optimization) are two main heuristic optimization methods,and are usually used as nonlinear inversion methods in geophysics. The authors applied BP neural n...BP( Back Propagation) neural network and PSO( Particle Swarm Optimization) are two main heuristic optimization methods,and are usually used as nonlinear inversion methods in geophysics. The authors applied BP neural network and BP neural network optimized with PSO into the inversion of 3D density interface respectively,and a comparison was drawn to demonstrate the inversion results. To start with,a synthetic density interface model was created and we used the proceeding inversion methods to test their effectiveness. And then two methods were applied into the inversion of the depth of Moho interface. According to the results,it is clear to find that the application effect of PSO-BP is better than that of BP network. The BP network structures used in both synthetic and field data are consistent in order to obtain preferable inversion results. The applications in synthetic and field tests demonstrate that PSO-BP is a fast and effective method in the inversion of 3D density interface and the optimization effect is evident compared with BP neural network merely,and thus,this method has practical value.展开更多
Seismic traveltime tomographic inversion has played an important role in detecting the internal structure of the solid earth. We use a set of blocks to approximate geologically complex media that cannot be well descri...Seismic traveltime tomographic inversion has played an important role in detecting the internal structure of the solid earth. We use a set of blocks to approximate geologically complex media that cannot be well described by layered models or cells. The geological body is described as an aggregate of arbitrarily shaped blocks,which are separated by triangulated interfaces. We can describe the media as homogenous or heterogeneous in each block. We define the velocities at the given rectangle grid points for each block,and the heterogeneous velocities in each block can be calculated by a linear interpolation algorithm. The parameters of the velocity grid positions are independent of the model parameterization,which is advantageous in the joint inversion of the velocities and the node depths of an interface. We implement a segmentally iterative ray tracer to calculate traveltimes in the 3D heterogeneous block models.The damped least squares method is employed in seismic traveltime inversion,which includes the partial derivatives of traveltime with respect to the depths of nodes in the triangulated interfaces and velocities defined in rectangular grids. The numerical tests indicate that the node depths of a triangulated interface and homogeneous velocity distributions can be well inverted in a stratified model.展开更多
光电极通常由半导体吸光层和导电集流体两部分组成,两者间的界面电子结构直接影响导电集流体从半导体光吸收层中收集光生电荷的效率,尤其对于具有3D界面结构的液态金属镶嵌半导体颗粒的光电极.为此,本工作通过改变金属组分改变液态金属...光电极通常由半导体吸光层和导电集流体两部分组成,两者间的界面电子结构直接影响导电集流体从半导体光吸收层中收集光生电荷的效率,尤其对于具有3D界面结构的液态金属镶嵌半导体颗粒的光电极.为此,本工作通过改变金属组分改变液态金属的功函数,从而调节导电集流体与半导体吸光材料间3D界面的电子能带排列和接触类型,促进光生电荷的跨界面转移与收集,提升光电极的光电化学分解水活性.系统研究半导体与液态金属的功函数匹配关系发现,将ZnO颗粒嵌入铟锡(IT)低温液态金属中,会形成欧姆接触;而将其嵌入铋铟锡(BIT)低温液态金属中,则会形成肖特基接触.由于欧姆接触不存在肖特基接触的界面能垒而有利于光生电荷的跨界面转移与收集,因此,与铟锡低温液态金属镶嵌ZnO颗粒的光电极(IT/ZnO)相比铋铟锡低温液态金属镶嵌ZnO颗粒的光电极(BIT/ZnO)具有更为优异的电荷收集和分离能力,其光电化学分解水光电流密度可达0.62 mA cm^(-2),相比BIT/ZnO光电极的光电流密度(0.52 mA cm^(-2))提升了约19%,且在已报道的代表性ZnO光电极中处于前列.而与之相比,WO3、TiO_(2)或Cu2O因分别与IT和BIT形成相同的欧姆或肖特基型接触,两种低温液态金属镶嵌的WO3、TiO_(2)或Cu2O光电极具有几乎相同的光电催化活性.本工作展示了通过选择具有不同功函数的液态金属来改变金属/半导体接触类型以增强低温液态金属镶嵌半导体光电极性能的潜力,为规模化构建高效光电极提供了新的策略.展开更多
Interacting with digital contents in 3 D is an essential task in various applications such as modeling packages, gaming, virtual reality, etc. Traditional interfaces using keyboard and mouse or trackball usually requi...Interacting with digital contents in 3 D is an essential task in various applications such as modeling packages, gaming, virtual reality, etc. Traditional interfaces using keyboard and mouse or trackball usually require a non-trivial amount of working space as well as a learning process. We present the design of EZ-Manipulator, a new 3 D manipulation interface using smartphones that supports mobile, fast, and ambiguity-free interaction with 3 D objects. Our system leverages the built-in multi-touch input and gyroscope sensor of smartphones to achieve 9 degrees-of-freedom axis-constrained manipulation and free-form rotation.Using EZ-Manipulator to manipulate objects in 3 D is easy. The user merely has to perform intuitive singleor two-finger gestures and rotate the hand-held device to perform manipulations at fine-grained and coarse levels respectively. We further investigate the ambiguity in manipulation introduced by indirect manipulations using a multi-touch interface, and propose a dynamic virtual camera adjustment to effectively resolve the ambiguity. A preliminary study shows that our system has significant lower task completion time compared to conventional use of a keyboard–mouse interface, and provides a positive user experience to both novices and experts.展开更多
In this paper,a fairly simple 3D immersed interface method based on the CG-Uzawa type method and the level set representation of the interface is employed for solving three-dimensional Stokes flow with singular forces...In this paper,a fairly simple 3D immersed interface method based on the CG-Uzawa type method and the level set representation of the interface is employed for solving three-dimensional Stokes flow with singular forces along the interface.The method is to apply the Taylor’s expansions only along the normal direction and incorporate the jump conditions up to the second normal derivatives into the finite difference schemes.A second order geometric iteration algorithm is employed for computing orthogonal projections on the surface with third-order accuracy.The Stokes equations are discretized involving the correction terms on staggered grids and then solved by the conjugate gradient Uzawa type method.The major advantages of the present method are the special simplicity,the ability in handling the Dirichlet boundary conditions,and no need of the pressure boundary condition.The method can also preserve the volume conservation and the discrete divergence free condition very well.The numerical results show that the proposed method is second order accurate and efficient.展开更多
In this paper, a vibration motion control is proposed and implemented on a foamed polystyrene machining robot to suppress the generation of undesirable cusp marks, and the basic performance of the controller is verifi...In this paper, a vibration motion control is proposed and implemented on a foamed polystyrene machining robot to suppress the generation of undesirable cusp marks, and the basic performance of the controller is verified through machining experiments of foamed polystyrene. Then, a 3 dimensional (3D) printer-like data interface is proposed for the machining robot. The 3D data inter- face enables to control the machining robot directly using stereolithography (STL) data without conducting any computer-aided man- ufacturing (CAM) process. This is done by developing a robotic preprocessor that helps to remove the need for the conventional CAM process by directly converting the STL data into cutter location source data called cutter location (CL) or cutter location source (CLS) data. The STL is a file format proposed by 3D systems, and recently is supported by many computer aided design (CAD)/CAM soft- waxes. The STL is widely used for rapid prototyping with a 3D printer which is a typical additive manufacturing system. The STL deals with a triangular representation of a curved surface geometry. The developed 3D printer-like data interface allows to directly control the machining robot through a zigzag path, rectangular spiral path and circular spiral path generated according to the information included in STL data. The effectiveness and usefulness of the developed system are demonstrated through actual machining experiments.展开更多
2022 The paper seeks to demonstrates the likelihood of embedding a 3D gaze point on a 3D visual field,the visual field is inform of a game console where the user has to play from one level to the other by overcoming o...2022 The paper seeks to demonstrates the likelihood of embedding a 3D gaze point on a 3D visual field,the visual field is inform of a game console where the user has to play from one level to the other by overcoming obstacles that will lead them to the next level.Complex game interface is sometimes difficult for the player to progress to next level of the game and the developers also find it difficult to regulate the game for an average player.The model serves as an analytical tool for game adaptations and also players can track their response to the game.Custom eye tracking and 3D object tracking algorithms were developed to enhance the analysis of the procedure.This is a part of the contributions to user interface design in the aspect of visual transparency.The development and testing of human computer interaction uses and application is more easily investigated than ever,part of the contribution to this is the embedding of 3-D gaze point on a 3-D visual field.This could be used in a number of applications,for instance in medical applications that includes long and short sightedness diagnosis and treatment.Experiments and Test were conducted on five different episodes of user attributes,result show that fixation points and pupil changes are the two most likely user attributes that contributes most significantly in the performance of the custom eye tracking algorithm the study.As the advancement in development of eye movement algorithm continues user attributes that showed the least likely appearance will prove to be redundant.展开更多
A new scheme is proposed to model 3D angular motion of a revolving regular object with miniature, low-cost micro electro mechanical systems(MEMS) accelerometers(instead of gyroscope),which is employed in 3D mouse syst...A new scheme is proposed to model 3D angular motion of a revolving regular object with miniature, low-cost micro electro mechanical systems(MEMS) accelerometers(instead of gyroscope),which is employed in 3D mouse system.To sense 3D angular motion,the static property of MEMS accelerometer,sensitive to gravity acceleration,is exploited.With the three outputs of configured accelerometers,the proposed model is implemented to get the rotary motion of the rigid object.In order to validate the effectiveness of the proposed model,an input device is developed with the configuration of the scheme.Experimental results show that a simulated 3D cube can accurately track the rotation of the input device.The result indicates the feasibility and effectiveness of the proposed model in the 3D mouse system.展开更多
In simulations of geotechnical engineering, interface elements are versatile tools and are widely used in the modeling of the relative displacements between soils and structures. To consider the case of a local failur...In simulations of geotechnical engineering, interface elements are versatile tools and are widely used in the modeling of the relative displacements between soils and structures. To consider the case of a local failure adjacent to a soil-structure interaction region, a partial mesh refinement should be performed. In this study, a three-dimensional(3 D) interface element with an arbitrary number of nodes is developed as a new technique to reduce the complexity and difficulty of managing the various scales between soil and structure. An asymmetric number of nodes is permissible on the two sliding surfaces. In this manner, soil and structure can be discretized independently, and the various-scale model is established conveniently and rapidly. The accuracy of the proposed method is demonstrated through numerical examples. The various-scale approach is employed in an elasto-plastic seismic damage analysis of a buried concrete drainage culvert of a nuclear power plant. The results indicate that by applying the proposed method, the number of elements decreased by 72.5%, and the computational efficiency improved by 59% with little influence on accuracy. The proposed method is powerful for local damage evolution analyses of both soil and structure and possesses great practical significance and the potential for further application, especially for nonlinear analysis of large-scale geotechnical engineering.展开更多
基金financially the National Natural Science Foundation of China(Nos.22178221,22208221)Shenzhen Science and Technology Program(Nos.JCYJ20200109105805902)+1 种基金Natural Science Foundation of Guangdong Province(Nos.2021A1515110751)China Postdoctoral Science Foundation(Nos.2021M702255)。
文摘The ripple effect induced by uncontrollable Zn deposition is considered as the Achilles heel for developing high-performance aqueous Zn-ion batteries.For this problem,this work reports a design concept of 3D artificial array interface engineering to achieve volume stress elimination,preferred orientation growth and dendrite-free stable Zn metal anode.The mechanism of MXene array interface on modulating the growth kinetics and deposition behavior of Zn atoms were firstly disclosed on the multi-scale level,including the in-situ optical microscopy and transient simulation at the mesoscopic scale,in-situ Raman spectroscopy and in-situ X-ray diffraction at the microscopic scale,as well as density functional theory calculation at the atomic scale.As indicated by the electrochemical performance tests,such engineered electrode exhibits the comprehensive enhancements not only in the resistance of corrosion and hydrogen evolution,but also the rate capability and cyclic stability.High-rate performance(20 mA cm^(-2))and durable cycle lifespan(1350 h at 0.5 mA cm^(-2),1500 h at 1 mA cm^(-2)and 800 h at 5 mA cm^(-2))can be realized.Moreover,the improvement of rate capability(214.1 mAh g^(-1)obtained at 10 A g^(-1))and cyclic stability also can be demonstrated in the case of 3D MXene array@Zn/VO2battery.Beyond the previous 2D closed interface engineering,this research offers a unique 3D open array interface engineering to stabilize Zn metal anode,the controllable Zn deposition mechanism revealed is also expected to deepen the fundamental of rechargeable batteries including but not limited to aqueous Zn metal batteries.
基金Supported by National High-tech Research&Development Program of China(863 Project)(No.2014AA06A613)
文摘BP( Back Propagation) neural network and PSO( Particle Swarm Optimization) are two main heuristic optimization methods,and are usually used as nonlinear inversion methods in geophysics. The authors applied BP neural network and BP neural network optimized with PSO into the inversion of 3D density interface respectively,and a comparison was drawn to demonstrate the inversion results. To start with,a synthetic density interface model was created and we used the proceeding inversion methods to test their effectiveness. And then two methods were applied into the inversion of the depth of Moho interface. According to the results,it is clear to find that the application effect of PSO-BP is better than that of BP network. The BP network structures used in both synthetic and field data are consistent in order to obtain preferable inversion results. The applications in synthetic and field tests demonstrate that PSO-BP is a fast and effective method in the inversion of 3D density interface and the optimization effect is evident compared with BP neural network merely,and thus,this method has practical value.
基金supported financially by the Ministry of Science and Technology of China(2011CB808904)the National Natural Science Foundation of China(Nos.41021063,41174075,41004034,41174043,and 41274090)
文摘Seismic traveltime tomographic inversion has played an important role in detecting the internal structure of the solid earth. We use a set of blocks to approximate geologically complex media that cannot be well described by layered models or cells. The geological body is described as an aggregate of arbitrarily shaped blocks,which are separated by triangulated interfaces. We can describe the media as homogenous or heterogeneous in each block. We define the velocities at the given rectangle grid points for each block,and the heterogeneous velocities in each block can be calculated by a linear interpolation algorithm. The parameters of the velocity grid positions are independent of the model parameterization,which is advantageous in the joint inversion of the velocities and the node depths of an interface. We implement a segmentally iterative ray tracer to calculate traveltimes in the 3D heterogeneous block models.The damped least squares method is employed in seismic traveltime inversion,which includes the partial derivatives of traveltime with respect to the depths of nodes in the triangulated interfaces and velocities defined in rectangular grids. The numerical tests indicate that the node depths of a triangulated interface and homogeneous velocity distributions can be well inverted in a stratified model.
基金financially supported by the National Key R&D Program of China (2021YFA1500800)the National Natural Science Foundation of China (52072377,and 51825204)+2 种基金the Youth Innovation Promotion Association of the Chinese Academy of Sciences (2020192)the CAS Projects for Young Scientists in Basic Research (YSBR-004)the financial support from the New Cornerstone Science Foundation through the XPLORER PRIZE。
文摘光电极通常由半导体吸光层和导电集流体两部分组成,两者间的界面电子结构直接影响导电集流体从半导体光吸收层中收集光生电荷的效率,尤其对于具有3D界面结构的液态金属镶嵌半导体颗粒的光电极.为此,本工作通过改变金属组分改变液态金属的功函数,从而调节导电集流体与半导体吸光材料间3D界面的电子能带排列和接触类型,促进光生电荷的跨界面转移与收集,提升光电极的光电化学分解水活性.系统研究半导体与液态金属的功函数匹配关系发现,将ZnO颗粒嵌入铟锡(IT)低温液态金属中,会形成欧姆接触;而将其嵌入铋铟锡(BIT)低温液态金属中,则会形成肖特基接触.由于欧姆接触不存在肖特基接触的界面能垒而有利于光生电荷的跨界面转移与收集,因此,与铟锡低温液态金属镶嵌ZnO颗粒的光电极(IT/ZnO)相比铋铟锡低温液态金属镶嵌ZnO颗粒的光电极(BIT/ZnO)具有更为优异的电荷收集和分离能力,其光电化学分解水光电流密度可达0.62 mA cm^(-2),相比BIT/ZnO光电极的光电流密度(0.52 mA cm^(-2))提升了约19%,且在已报道的代表性ZnO光电极中处于前列.而与之相比,WO3、TiO_(2)或Cu2O因分别与IT和BIT形成相同的欧姆或肖特基型接触,两种低温液态金属镶嵌的WO3、TiO_(2)或Cu2O光电极具有几乎相同的光电催化活性.本工作展示了通过选择具有不同功函数的液态金属来改变金属/半导体接触类型以增强低温液态金属镶嵌半导体光电极性能的潜力,为规模化构建高效光电极提供了新的策略.
文摘Interacting with digital contents in 3 D is an essential task in various applications such as modeling packages, gaming, virtual reality, etc. Traditional interfaces using keyboard and mouse or trackball usually require a non-trivial amount of working space as well as a learning process. We present the design of EZ-Manipulator, a new 3 D manipulation interface using smartphones that supports mobile, fast, and ambiguity-free interaction with 3 D objects. Our system leverages the built-in multi-touch input and gyroscope sensor of smartphones to achieve 9 degrees-of-freedom axis-constrained manipulation and free-form rotation.Using EZ-Manipulator to manipulate objects in 3 D is easy. The user merely has to perform intuitive singleor two-finger gestures and rotate the hand-held device to perform manipulations at fine-grained and coarse levels respectively. We further investigate the ambiguity in manipulation introduced by indirect manipulations using a multi-touch interface, and propose a dynamic virtual camera adjustment to effectively resolve the ambiguity. A preliminary study shows that our system has significant lower task completion time compared to conventional use of a keyboard–mouse interface, and provides a positive user experience to both novices and experts.
基金supported by the Special Project on High-performance Computing under the National Key R&D Program(No.2016YFB0200604)National Natural Science Foundation of China(11971502,11571385)Guangdong Natural Science Foundation(2017A030313017).
文摘In this paper,a fairly simple 3D immersed interface method based on the CG-Uzawa type method and the level set representation of the interface is employed for solving three-dimensional Stokes flow with singular forces along the interface.The method is to apply the Taylor’s expansions only along the normal direction and incorporate the jump conditions up to the second normal derivatives into the finite difference schemes.A second order geometric iteration algorithm is employed for computing orthogonal projections on the surface with third-order accuracy.The Stokes equations are discretized involving the correction terms on staggered grids and then solved by the conjugate gradient Uzawa type method.The major advantages of the present method are the special simplicity,the ability in handling the Dirichlet boundary conditions,and no need of the pressure boundary condition.The method can also preserve the volume conservation and the discrete divergence free condition very well.The numerical results show that the proposed method is second order accurate and efficient.
基金supported by the Japam Society for the Promotion of Science(JSPS)KAKENHI(Nos.25420232 and 16K06203)
文摘In this paper, a vibration motion control is proposed and implemented on a foamed polystyrene machining robot to suppress the generation of undesirable cusp marks, and the basic performance of the controller is verified through machining experiments of foamed polystyrene. Then, a 3 dimensional (3D) printer-like data interface is proposed for the machining robot. The 3D data inter- face enables to control the machining robot directly using stereolithography (STL) data without conducting any computer-aided man- ufacturing (CAM) process. This is done by developing a robotic preprocessor that helps to remove the need for the conventional CAM process by directly converting the STL data into cutter location source data called cutter location (CL) or cutter location source (CLS) data. The STL is a file format proposed by 3D systems, and recently is supported by many computer aided design (CAD)/CAM soft- waxes. The STL is widely used for rapid prototyping with a 3D printer which is a typical additive manufacturing system. The STL deals with a triangular representation of a curved surface geometry. The developed 3D printer-like data interface allows to directly control the machining robot through a zigzag path, rectangular spiral path and circular spiral path generated according to the information included in STL data. The effectiveness and usefulness of the developed system are demonstrated through actual machining experiments.
文摘2022 The paper seeks to demonstrates the likelihood of embedding a 3D gaze point on a 3D visual field,the visual field is inform of a game console where the user has to play from one level to the other by overcoming obstacles that will lead them to the next level.Complex game interface is sometimes difficult for the player to progress to next level of the game and the developers also find it difficult to regulate the game for an average player.The model serves as an analytical tool for game adaptations and also players can track their response to the game.Custom eye tracking and 3D object tracking algorithms were developed to enhance the analysis of the procedure.This is a part of the contributions to user interface design in the aspect of visual transparency.The development and testing of human computer interaction uses and application is more easily investigated than ever,part of the contribution to this is the embedding of 3-D gaze point on a 3-D visual field.This could be used in a number of applications,for instance in medical applications that includes long and short sightedness diagnosis and treatment.Experiments and Test were conducted on five different episodes of user attributes,result show that fixation points and pupil changes are the two most likely user attributes that contributes most significantly in the performance of the custom eye tracking algorithm the study.As the advancement in development of eye movement algorithm continues user attributes that showed the least likely appearance will prove to be redundant.
文摘A new scheme is proposed to model 3D angular motion of a revolving regular object with miniature, low-cost micro electro mechanical systems(MEMS) accelerometers(instead of gyroscope),which is employed in 3D mouse system.To sense 3D angular motion,the static property of MEMS accelerometer,sensitive to gravity acceleration,is exploited.With the three outputs of configured accelerometers,the proposed model is implemented to get the rotary motion of the rigid object.In order to validate the effectiveness of the proposed model,an input device is developed with the configuration of the scheme.Experimental results show that a simulated 3D cube can accurately track the rotation of the input device.The result indicates the feasibility and effectiveness of the proposed model in the 3D mouse system.
基金supported by the National Key R&D Program of China(Grant No.2017YFC0404900)the National Natural Science Foundation of China(Grant Nos.51779034,51678113)the Fundamental Research Funds for the Central Universities(Grant No.DUT17ZD219)
文摘In simulations of geotechnical engineering, interface elements are versatile tools and are widely used in the modeling of the relative displacements between soils and structures. To consider the case of a local failure adjacent to a soil-structure interaction region, a partial mesh refinement should be performed. In this study, a three-dimensional(3 D) interface element with an arbitrary number of nodes is developed as a new technique to reduce the complexity and difficulty of managing the various scales between soil and structure. An asymmetric number of nodes is permissible on the two sliding surfaces. In this manner, soil and structure can be discretized independently, and the various-scale model is established conveniently and rapidly. The accuracy of the proposed method is demonstrated through numerical examples. The various-scale approach is employed in an elasto-plastic seismic damage analysis of a buried concrete drainage culvert of a nuclear power plant. The results indicate that by applying the proposed method, the number of elements decreased by 72.5%, and the computational efficiency improved by 59% with little influence on accuracy. The proposed method is powerful for local damage evolution analyses of both soil and structure and possesses great practical significance and the potential for further application, especially for nonlinear analysis of large-scale geotechnical engineering.