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NEW VISUAL METHOD FOR FREE-FORM SURFACE RECONSTRUCTION 被引量:1
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作者 Xiong Hanwei Artificial Intelligence Institute,Zhejiang University,Hangzhou 310027,China Zhang Xiangwei Guangdong University of Technology 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2002年第1期35-39,共5页
A new method is put forward combining computer vision with computer aidedgeometric design (CAGD) to resolve the problem of free-form surface reconstruction. The surface isfirst subdivided into N-sided Gregory patches,... A new method is put forward combining computer vision with computer aidedgeometric design (CAGD) to resolve the problem of free-form surface reconstruction. The surface isfirst subdivided into N-sided Gregory patches, and a stereo algorithm is used to reconstruct theboundary curves. Then, the cross boundary tangent vectors are computed through reflectance analysis.At last, the whole surface can be reconstructed jointing these patches with G^1 continuity(tangentcontinuity). Examples on synthetic images are given. 展开更多
关键词 Reverse engineering free-form surface design Computer vision
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Steering surface reconstruction of hybrid metal oxides for efficient oxygen evolution reaction in water splitting and zinc-air batteries
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作者 Jie Zhu Junxue Chen +7 位作者 Xida Li Kun Luo Zewei Xiong Zhiyu Zhou Wenyun Zhu Zhihong Luo Jingbin Huang Yibing Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期383-393,共11页
Surface reconstruction yields real active species in electrochemical oxygen evolution reaction(OER)conditions;however,rationally regulating reconstruction in a targeted manner for constructing highly active OER electr... Surface reconstruction yields real active species in electrochemical oxygen evolution reaction(OER)conditions;however,rationally regulating reconstruction in a targeted manner for constructing highly active OER electrocatalysts remains a formidable challenge.Here,an electrochemical activation strategy with selective etching was utilized to guide the reconstruction process of a hybrid cobalt-molybdenum oxide(CoMoO_(4)/Co_(3)O_(4)@CC)in a favorable direction to improve the OER performance.Both in-situ Raman and multiple ex-situ characterization tools demonstrate that controlled surface reconstruction can be easily achieved through Mo etching,with the formation of a dynamically stable amorphous-crystalline heterostructure.Theoretical calculations together with experimental results reveal that the synergistic effects between amorphous CoOOH and crystalline Co_(3)O_(4) are crucial in enhancing the catalytic performance.Consequently,the reconstructed CoMoO_(4)/Co_(3)O_(4)@CC exhibits a low overpotential of 250 mV to achieve a current density of 10 mA cm^(-2) in 1 M KOH,and more importantly it can be practiced in electrolytic water splitting and rechargeable zinc-air batteries devices,achieving ultra-long stability for over 500 and 1200 h,respectively.This work provides a promising route for the construction of high-performance electrocatalysts. 展开更多
关键词 ELECTROCATALYST Oxygen evolution reaction surface reconstruction Selective etching Amorphous-crystalline heterostructures
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Covalency competition induced selective bond breakage and surface reconstruction in manganese cobaltite towards enhanced electrochemical charge storage
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作者 Peng Gao Pei Tang +7 位作者 Ying Mo Peitao Xiao Wang Zhou Shi Chen Hongliang Dong Ziwei Li Chaohe Xu Jilei Liu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期909-918,共10页
Manganese cobaltite(MnCo_(2)_(4))is a promising electrode material because of its attractive redox chemistry and excellent charge storage capability.Our previous work demonstrated that the octahedrally-coordinated Mn ... Manganese cobaltite(MnCo_(2)_(4))is a promising electrode material because of its attractive redox chemistry and excellent charge storage capability.Our previous work demonstrated that the octahedrally-coordinated Mn are prone to react with the hydroxyl ions in alkaline electrolyte upon electrochemical cycling and separates on the surface of spinel to reconstruct into d-MnO_(2) nanosheets irreversibly,thus results in a change of the reaction mechanism with Kþion intercalation.However,the low capacity has greatly limited its practical application.Herein,we found that the tetrahedrally-coordinated Co_(2) þions were leached when MnCo_(2)_(4) was equilibrated in 1 mol L^(-1) HCl solution,leading to the formation of layered CoOOH on MnCo_(2)_(4) surface which is originated from the covalency competition induced selective breakage of the CoT–O bond in CoT–O–CoO and subsequent rearrangement of free Co_(6) octahedra.The as-formed CoOOH is stable upon cycling in alkaline electrolyte,exhibits conversion reaction mechanism with facile proton diffusion and is free of massive structural evolution,thus enables utilization of the bulk electrode material and realizes enhanced specific capacity as well as facilitated charge transfer and ion diffusion.In general,our work not only offers a feasible approach to deliberate modification of MnCo_(2)_(4)'s surface structure,but also provides an in-depth understanding of its charge storage mechanism,which enables rational design of the spinel oxides with promising charge storage properties. 展开更多
关键词 Manganese cobaltite Tetrahedrally-coordinated Co^(2+)leaching Selective bond breakage surface reconstruction Charge storage mechanisms
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Medical and surgical approach to ocular surface reconstruction
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作者 Daniella Lent-Schochet Asim Dhungana +2 位作者 Inae Jang Kim Hassan Shah Asim V.Farooq 《Annals of Eye Science》 2024年第1期43-59,共17页
Ocular surface disease(OSD)can have a severe impact on patients as it can lead to visual impairment and persistent discomfort.Ocular surface reconstruction(OSR)is an approach to the management of ocular diseases that ... Ocular surface disease(OSD)can have a severe impact on patients as it can lead to visual impairment and persistent discomfort.Ocular surface reconstruction(OSR)is an approach to the management of ocular diseases that cause structural damage to the ocular surface.OSR encompasses both medical and surgical treatment options.In this review,we discuss the medical and surgical strategies used in OSR.Medical management often aims to treat tear insufficiency,inflammation,and keratinization.Surgical treatments may be employed for a variety of reasons,including failure of medical management.This may include improving the oculo-palpebral structures in order to improve lid positioning and tear film.Additional therapies focus on improving tear production,such as through salivary gland transplantation.In situations where the ocular surface is so severely damaged that there is loss of limbal stem cells,limbal stem cell transplant(LSCT)may be indicated.Other surgeries such as amniotic membrane transplant(AMT)and conjunctival flaps(CFs)can help promote corneal healing.Finally,in severe situations where the cornea is beyond salvage,corneal transplantation,such as a penetrating keratoplasty(PKP),can be considered.OSR often requires a combination of medical and surgical approaches targeted to each specific patient’s presentation in order to achieve optimal outcomes. 展开更多
关键词 Ocular surface reconstruction(OSR) ocular surface disease(OSD) amniotic membrane transplant(AMT) limbal stem cell transplant(LSCT) eyelid reconstruction
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Etching‑Induced Surface Reconstruction of NiMoO_(4) for Oxygen Evolution Reaction 被引量:5
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作者 Jinli Zhu Jinmei Qian +2 位作者 Xuebing Peng Baori Xia Daqiang Gao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第2期271-282,共12页
Rational reconstruction of oxygen evolution reaction(OER)precatalysts and performance index of OER catalysts are crucial but still challenging for universal water electrolysis.Herein,we develop a double-cation etching... Rational reconstruction of oxygen evolution reaction(OER)precatalysts and performance index of OER catalysts are crucial but still challenging for universal water electrolysis.Herein,we develop a double-cation etching strategy to tailor the electronic structure of NiMoO_(4),where the prepared NiMoO_(4) nanorods etched by H_(2)O_(2) reconstruct their surface with abundant cation deficiencies and lattice distortion.Calculation results reveal that the double cation deficiencies can make the upshift of d-band center for Ni atoms and the active sites with better oxygen adsorption capacity.As a result,the optimized sample(NMO-30M)possesses an overpotential of 260 mV at 10 mA cm−2 and excellent long-term durability of 162 h.Importantly,in situ Raman test reveals the rapid formation of high-oxidation-state transition metal hydroxide species,which can further help to improve the catalytic activity of NiMoO_(4) in OER.This work highlights the influence of surface remodification and shed some light on activating catalysts. 展开更多
关键词 ETCHING surface reconstruction Cation deficiencies OER
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Anti-Corrosion and Reconstruction of Surface Crystal Plane for Zn Anodes by an Advanced Metal Passivation Technique 被引量:1
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作者 Si Liu Hongxin Lin +2 位作者 Qianqian Song Jian Zhu Changbao Zhu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期166-172,共7页
For the aqueous Zn-ion battery,dendrite formation,corrosion,and interfacial parasitic reactions are major issues,which greatly inhibits their practical application.How to develop a method of Zn construction or treatme... For the aqueous Zn-ion battery,dendrite formation,corrosion,and interfacial parasitic reactions are major issues,which greatly inhibits their practical application.How to develop a method of Zn construction or treatment to solve these issues for Zn anodes are still great challenges.Herein,a simple and cheap metal passivation technique is proposed for Zn anodes from a corrosion science perspective.Similar to the metal anticorrosion engineering,the formed interfacial protective layer in a chemical way can sufficiently solve the corrosion issues.Furthermore,the proposed passivity approach can reconstruct Zn surface-preferred crystal planes,exposing more(002)planes and improving surface hydrophilicity,which inhibits the formation of Zn dendrites and hydrogen evolution effectively.As expected,the passivated Zn achieves outstanding cycling life(1914 h)with low voltage polarization(<40 mV).Even at 6 mA cm^(−2) and 3 mA h cm^(−2),it can achieve stable Zn deposition over 460 h.The treated Zn anode coupled with MnO_(2) cathode shows prominently reinforced full batteries service life,making it a potential Zn anode candidate for excellent performance aqueous Zn-ion batteries.The proposed passivation approach provides a guideline for other metal electrodes preparation in various batteries and establishes the connections between corrosion science and batteries. 展开更多
关键词 ANTI-CORROSION aqueous zinc ion battery interfacial protective layer metal passivation technique reconstruction of surface crystal plane
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Reconstruction and stability of Fe_(3)O_(4)(001)surface:An investigation based on particle swarm optimization and machine learning
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作者 柳洪盛 赵圆圆 +2 位作者 邱实 赵纪军 高峻峰 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期27-31,共5页
Magnetite nanoparticles show promising applications in drug delivery,catalysis,and spintronics.The surface of magnetite plays an important role in these applications.Therefore,it is critical to understand the surface ... Magnetite nanoparticles show promising applications in drug delivery,catalysis,and spintronics.The surface of magnetite plays an important role in these applications.Therefore,it is critical to understand the surface structure of Fe_(3)O_(4)at atomic scale.Here,using a combination of first-principles calculations,particle swarm optimization(PSO)method and machine learning,we investigate the possible reconstruction and stability of Fe_(3)O_(4)(001)surface.The results show that besides the subsurface cation vacancy(SCV)reconstruction,an A layer with Fe vacancy(A-layer-V_(Fe))reconstruction of the(001)surface also shows very low surface energy especially at oxygen poor condition.Molecular dynamics simulation based on the iron–oxygen interaction potential function fitted by machine learning further confirms the thermodynamic stability of the A-layer-V_(Fe)reconstruction.Our results are also instructive for the study of surface reconstruction of other metal oxides. 展开更多
关键词 surface reconstruction magnetite surface particle swarm optimization machine learning
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Surface reconstruction of Se-doped NiS_(2) enables high-efficiency oxygen evolution reaction
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作者 Mengxin Chen Yuanyuan Zhang +5 位作者 Ran Wang Bin Zhang Bo Song Yanchao Guan Siwei Li Ping Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第9期173-180,共8页
Surface reconstruction of electrocatalysts has been widely witnessed during the electrochemical processes.Here,NiS_(2),NiSe_(2), and Se doped NiS_(2)(Se-NiS_(2)) are fabricated for oxygen evolution reaction(OER) throu... Surface reconstruction of electrocatalysts has been widely witnessed during the electrochemical processes.Here,NiS_(2),NiSe_(2), and Se doped NiS_(2)(Se-NiS_(2)) are fabricated for oxygen evolution reaction(OER) through a mild sulfuration and/or selenylation process of Ni(OH)_(2) supported on carbon cloth(CC).Through careful in-situ Raman spectroscopy and ex-situ X-ray photoelectron spectroscopy,surface reconstruction of NiS_(2),NiSe_(2),and Se-NiS_(2) during the OER process has been revealed.A potentialdependent study shows that Se-NiS_(2) undergoes surface evolution at lower potentials and requires the lowest potential for conversion to NiOOH as a highly OER-active species,accompanied by the leaching of SO_(4)^(2-) and SeO_(4)^(2-) that can again be adsorbed on the catalyst surface to enhance the catalytic activity.Density functional theory(DFT) calculations confirm that Se-NiS_(2) is more susceptible to surface oxidation through the OER process.Therefore,Se-NiS_(2) exhibits outstanding OER activity and stability in alkaline conditions,requiring an overpotential of 343 mV at a current density of 50 mA cm^(-2).A novel insight is provided by our work in understanding the surface reconstruction and electrocatalytic mechanism of Ni-based chalcogenides. 展开更多
关键词 Oxygen evolution reaction Se-NiS_(2) In-situ Raman spectroscopy Anion leaching surface reconstruction
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Unveiling the parasitic-reaction-driven surface reconstruction in Ni-rich cathode and the electrochemical role of Li_(2)CO_(3)
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作者 Jiyu Cai Zhenzhen Yang +18 位作者 Xinwei Zhou Bingning Wang Ana Suzana Jianming Bai Chen Liao Yuzi Liu Yanbin Chen Shunlin Song Xuequan Zhang Li Wang Xiangming He Xiangbo Meng Niloofar Karami Baasit Ali Shaik Sulaiman Natasha A.Chernova Shailesh Upreti Brad Prevel Feng Wang Zonghai Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期126-136,I0006,共12页
Nickel-rich transition-metal oxides are widely regarded as promising cathode materials for high-energydensity lithium-ion batteries for emerging electric vehicles. However, achieving high energy density in Ni-rich cat... Nickel-rich transition-metal oxides are widely regarded as promising cathode materials for high-energydensity lithium-ion batteries for emerging electric vehicles. However, achieving high energy density in Ni-rich cathodes is accompanied by substantial safety and cycle-life obstacles. The major issues of Ni-rich cathodes at high working potentials are originated from the unstable cathode-electrolyte interface, while the underlying mechanism of parasitic reactions towards surface reconstructions of cathode materials is not well understood. In this work, we controlled the Li_(2)CO_(3) impurity content on LiNi_(0.83)Mn_(0.1)Co_(0.07)O_(2) cathodes using air, tank-air, and O_(2) synthesis environments. Home-built high-precision leakage current and on-line electrochemical mass spectroscopy experiments verify that Li_(2)CO_(3) impurity is a significant promoter of parasitic reactions on Ni-rich cathodes. The rate of parasitic reactions is strongly correlated to Li_(2)CO_(3) content and severe performance deterioration of Ni83 cathodes.The post-mortem characterizations via high-resolution transition electron microscope and X-ray photoelectron spectroscopy depth profiles reveal that parasitic reactions promote more Ni reduction and O deficiency and even rock-salt phase transformation at the surface of cathode materials. Our observation suggests that surface reconstructions have a strong affiliation to parasitic reactions that create chemically acidic environment to etch away the lattice oxygen and offer the electrical charge to reduce the valence state of transition metal. Thus, this study advances our understanding on surface reconstructions of Nirich cathodes and prepares us for searching for rational strategies. 展开更多
关键词 Ni-rich cathodes surface reconstructions Phase transformation Parasitic reactions Li_(2)CO_(3)
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Surface reconstruction of complex contour lines based on chain code matching technique 被引量:1
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作者 姜晓彤 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期432-435,共4页
A new method for solving the tiling problem of surface reconstruction is proposed. The proposed method uses a snake algorithm to segment the original images, the contours are then transformed into strings by Freeman'... A new method for solving the tiling problem of surface reconstruction is proposed. The proposed method uses a snake algorithm to segment the original images, the contours are then transformed into strings by Freeman' s code. Symbolic string matching technique is applied to establish a correspondence between the two consecutive contours. The surface is composed of the pieces reconstructed from the correspondence points. Experimental results show that the proposed method exhibits a good behavior for the quality of surface reconstruction and its time complexity is proportional to mn where m and n are the numbers of vertices of the two consecutive slices, respectively. 展开更多
关键词 chain code string matching surface reconstruction local shape feature
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Self-derivation and reconstruction of silver nanoparticle reinforced cobalt-nickel bimetallic hydroxides through interface engineering for overall water splitting
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作者 Yan Li Jie Han +5 位作者 Weiwei Bao Junjun Zhang Taotao Ai Mameng Yang Chunming Yang Pengfei Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期590-599,I0013,共11页
Designing efficient and long-lasting non-metal electrocatalysts is an urgent task for addressing the issue of kinetic hysteresis in electrochemical oxidation reactions.The bimetallic hydroxides,catalyzing the oxygen e... Designing efficient and long-lasting non-metal electrocatalysts is an urgent task for addressing the issue of kinetic hysteresis in electrochemical oxidation reactions.The bimetallic hydroxides,catalyzing the oxygen evolution reaction(OER),have significant research potential because hydroxide reconstruction to generate an active phase is a remarkable advantage.Herein,the complete reconstruction of ultrathin CoNi(OH)_(2) nanosheets was achieved by embedding Ag nanoparticles into the hydroxide to induce a spontaneous redox reaction(SRR),forming heterojunction Ag@CoNi(OH)_(2) for bifunctional hydrolysis.Theoretical calculations and in situ Raman and ex situ characterizations revealed that the inductive effect of the Ag cation redistributed the charge to promote phase transformation to highly activate Ag-modified hydroxides.The Co-Ni dual sites in Co/NiOOH serve as novel active sites for optimizing the intermediates,thereby weakening the barrier formed by OOH^*.Ag@CoNi(OH)_(2) required a potential of 1.55 V to drive water splitting at a current density of 10 mA cm^(-2),with nearly 98.6% Faraday efficiency.Through ion induction and triggering of electron regulation in the OER via the synergistic action of the heterogeneous interface and surface reconstruction,this strategic design can overcome the limited capacity of bimetallic hydroxides and bridge the gap between the basic theory and industrialization of water decomposition. 展开更多
关键词 surface reconstruction Bimetallic hydroxides Ag nanoparticle Operando Raman Overall water splitting
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Multi-View Image-Based 3D Reconstruction in Indoor Scenes:A Survey
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作者 LU Ping SHI Wenzhe QIAO Xiuquan 《ZTE Communications》 2024年第3期91-98,共8页
Three-dimensional reconstruction technology plays an important role in indoor scenes by converting objects and structures in indoor environments into accurate 3D models using multi-view RGB images.It offers a wide ran... Three-dimensional reconstruction technology plays an important role in indoor scenes by converting objects and structures in indoor environments into accurate 3D models using multi-view RGB images.It offers a wide range of applications in fields such as virtual reality,augmented reality,indoor navigation,and game development.Existing methods based on multi-view RGB images have made significant progress in 3D reconstruction.These image-based reconstruction methods not only possess good expressive power and generalization performance,but also handle complex geometric shapes and textures effectively.Despite facing challenges such as lighting variations,occlusion,and texture loss in indoor scenes,these challenges can be effectively addressed through deep neural networks,neural implicit surface representations,and other techniques.The technology of indoor 3D reconstruction based on multi-view RGB images has a promising future.It not only provides immersive and interactive virtual experiences but also brings convenience and innovation to indoor navigation,interior design,and virtual tours.As the technology evolves,these image-based reconstruction methods will be further improved to provide higher quality and more accurate solutions to indoor scene reconstruction. 展开更多
关键词 3D reconstruction MVS NeRF neural implicit surface
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A Computer Vision Method for 3D Reconstruction of Curves-Marked Free-Form Surfaces
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作者 Xiong Hanwei①② Zhang Xiangwei② ①AI Institute of Zhejiang University, Hangzhou 310027, China ②Mechanic & Electronic Department of Shantou University, Shanton 515063, China) 《Computer Aided Drafting,Design and Manufacturing》 2001年第1期41-47,共7页
Visual method is now broadly used in reverse engineering for 3D reconstruction. The traditional computer vision methods are feature-based, i.e., they require that the objects must reveal features owing to geometry or ... Visual method is now broadly used in reverse engineering for 3D reconstruction. The traditional computer vision methods are feature-based, i.e., they require that the objects must reveal features owing to geometry or textures. For textureless free-form surfaces, dense feature points are added artificially. In this paper, a new method is put forward combining computer vision with CAGD. The surface is subdivided into N-side Gregory patches using marked curves, and a stereo algorithm is used to reconstruct the curves. Then, the cross boundary tangent vector is computed through reflectance analysis. At last, the whole surface can be reconstructed by jointing these patches with 1Gcontinuity. 展开更多
关键词 Reverse engineering free-form surface design Computer vision
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COMPLEX SURFACE RECONSTRUCTION BASED ON OBJECT-ORIENTED DEVELOPING TOOL VBA 被引量:5
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作者 Li Yupeng Wang Hong School of Mechanical Engineering, Yanshan University, Qinhuangdao 066004, China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2002年第3期248-251,共4页
Taking AutoCAD2000 as platform, an algorithm for the reconstruction ofsurface from scattered data points based on VBA is presented. With this core technology customerscan be free from traditional AutoCAD as an electro... Taking AutoCAD2000 as platform, an algorithm for the reconstruction ofsurface from scattered data points based on VBA is presented. With this core technology customerscan be free from traditional AutoCAD as an electronic board and begin to create actual presentationof real-world objects. VBA is not only a very powerful tool of development, but with very simplesyntax. Associating with those solids, objects and commands of AutoCAD 2000, VBA notably simplifiesprevious complex algorithms, graphical presentations and processing, etc. Meanwhile, it can avoidappearance of complex data structure and data format in reverse design with other modeling software.Applying VBA to reverse engineering can greatly improve modeling efficiency and facilitate surfacereconstruction. 展开更多
关键词 Reverse designing Scattered data points Topological mesh VBAenvironment Complex surface reconstruction
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Fatigue life prediction of workpiece with 3D rough surface topography based on surface reconstruction technology 被引量:5
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作者 LI Guo-wen TANG Jin-yuan +1 位作者 ZHOU Wei LI Lin 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第9期2069-2075,共7页
The fatigue performance of a workpiece depends on its surface quality.In traditional fatigue life prediction,the effect of surface quality is commonly accounted for by using empirical correction factors,which is impre... The fatigue performance of a workpiece depends on its surface quality.In traditional fatigue life prediction,the effect of surface quality is commonly accounted for by using empirical correction factors,which is imprecise when safety is of great concern.For surface quality,the surface topography is an important parameter,which introduces stress concentration that reduces the fatigue life.It is not feasible to test the stress concentration of different surface topographies.On the one hand,it is time-consuming and high-cost,and on the other hand,it cannot reflect the general statistical characteristics.With the help of surface reconstruction technology and interpolation method,a more efficient and economic approach is proposed,where FE simulation of workpiece with the reconstructed surface topography is used as a foundation for fatigue life prediction.The relationship between surface roughness(Sa)and fatigue life of the workpiece is studied with the proposed approach. 展开更多
关键词 fatigue life stress concentration surface reconstruction technology surface topography
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Three-Dimensional Reconstruction of Welding Pool Surface by Binocular Vision 被引量:7
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作者 Zunan Gu Ji Chen Chuansong Wu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第3期272-284,共13页
Current research of binocular vision systems mainly need to resolve the camera’s intrinsic parameters before the reconstruction of three-dimensional(3D)objects.The classical Zhang’calibration is hardly to calculate ... Current research of binocular vision systems mainly need to resolve the camera’s intrinsic parameters before the reconstruction of three-dimensional(3D)objects.The classical Zhang’calibration is hardly to calculate all errors caused by perspective distortion and lens distortion.Also,the image-matching algorithm of the binocular vision system still needs to be improved to accelerate the reconstruction speed of welding pool surfaces.In this paper,a preset coordinate system was utilized for camera calibration instead of Zhang’calibration.The binocular vision system was modified to capture images of welding pool surfaces by suppressing the strong arc interference during gas metal arc welding.Combining and improving the algorithms of speeded up robust features,binary robust invariant scalable keypoints,and KAZE,the feature information of points(i.e.,RGB values,pixel coordinates)was extracted as the feature vector of the welding pool surface.Based on the characteristics of the welding images,a mismatch-elimination algorithm was developed to increase the accuracy of image-matching algorithms.The world coordinates of matching feature points were calculated to reconstruct the 3D shape of the welding pool surface.The effectiveness and accuracy of the reconstruction of welding pool surfaces were verified by experimental results.This research proposes the development of binocular vision algorithms that can reconstruct the surface of welding pools accurately to realize intelligent welding control systems in the future. 展开更多
关键词 surface reconstruction Welding pool Binocular imaging Gas metal arc welding Feature points matching
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RECONSTRUCTION OF WELD POOL SURFACE BASED ON SHAPE FROM SHADING 被引量:2
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作者 DU Quanying CHEN Shanben LIN Tao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第2期168-171,共4页
A valid image-processing algorithm of weld pool surface reconstruction according to an input image of weld pool based on shape from shading (SFS) in computer vision is presented. The weld pool surface information is... A valid image-processing algorithm of weld pool surface reconstruction according to an input image of weld pool based on shape from shading (SFS) in computer vision is presented. The weld pool surface information is related to the backside weld width, which is crucial to the quality of weld joint. The image of weld pool is recorded with an optical sensing method. Firstly, the reflectance map model, which specifies the imaging process, is estimated. Then, the algorithm of weld pool surface reconstruction based on SFS is implemented by iteration scheme and speeded by hierarchical structure. The results indicate the accuracy and effectiveness of the approach. 展开更多
关键词 Weld pool surface reconstruction Reflectance map model Shape from shading(SFS)
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First-principles Study on Geometric and Electronic Structures of Si(111)-√7× √3-In Surface Reconstruction
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作者 商波 袁岚峰 杨金龙 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第4期403-408,I0003,共7页
In order to determine the structures of Si(111)-√7 √3-In surfaces and to understand their electronic properties, we construct six models of both hexagonal and rectangular types and perform first-principles calcula... In order to determine the structures of Si(111)-√7 √3-In surfaces and to understand their electronic properties, we construct six models of both hexagonal and rectangular types and perform first-principles calculations. Their scanning tunneling microscopic images and work functions are simulated and compared with experimental results. In this way, the hex-H3' and rect-T1 models are identified as the experimental configurations for the hexagonal and rectangular types, respectively. The structural evolution mechanism of the In/Si(lll) surface with indium coverage around 1.0 monolayer is discussed. The 4×1 and -√7× √3 phases are suggested to have two different types of evolution mechanisms, consistent with experimental results. 展开更多
关键词 surface reconstruction Si(111)-√7× √3In Density functional theory Scanning tunnueling microscopic image
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Study on resource quantity of surface water based on phase space reconstruction and neural network 被引量:5
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作者 曹连海 郝仕龙 陈南祥 《Journal of Coal Science & Engineering(China)》 2006年第1期39-42,共4页
Proposed a new method to disclose the complicated non-linearity structure of the water-resource system, introducing chaos theory into the hydrology and water resources field, and combined with the chaos theory and art... Proposed a new method to disclose the complicated non-linearity structure of the water-resource system, introducing chaos theory into the hydrology and water resources field, and combined with the chaos theory and artificial neural networks. Training data construction and networks structure were determined by the phase space reconstruction, and establishing nonlinear relationship of phase points with neural networks, the forecasting model of the resource quantity of the surface water was brought forward. The keystone of the way and the detailed arithmetic of the network training were given. The example shows that the model has highly forecasting precision. 展开更多
关键词 phase space reconstruction neural network resource quantity of the surface water forecasting model
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Surface Reconstruction of 3D Scattered Data with Radial Basis Functions 被引量:1
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作者 Du XIN-WEI YANG XIAO-YING LIANG XUE-ZHANG 《Communications in Mathematical Research》 CSCD 2010年第2期183-192,共10页
We use Radial Basis Functions (RBFs) to reconstruct smooth surfaces from 3D scattered data. An object's surface is defined implicitly as the zero set of an RBF fitted to the given surface data. We propose improveme... We use Radial Basis Functions (RBFs) to reconstruct smooth surfaces from 3D scattered data. An object's surface is defined implicitly as the zero set of an RBF fitted to the given surface data. We propose improvements on the methods of surface reconstruction with radial basis functions. A sparse approximation set of scattered data is constructed by reducing the number of interpolating points on the surface. We present an adaptive method for finding the off-surface normal points. The order of the equation decreases greatly as the number of the off-surface constraints reduces gradually. Experimental results are provided to illustrate that the proposed method is robust and may draw beautiful graphics. 展开更多
关键词 radial basis function scattered data implicit surface surface reconstruction
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