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Path,feedrate and trajectory planning for free-form surface machining:A state-of-the-art review 认领 引用 被引量：20
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作者 Yuwen SUN Jinjie JIA +2 位作者 Jinting XU Mansen CHEN Jinbo NIU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第8期12-29,共18页
Nowadays,free-form surfaces have been widely used in various industrial fields.They are usually machined by CNC machine tools,but recently have also begun to be manufactured by industrial robotic arm manipulators,than... Nowadays,free-form surfaces have been widely used in various industrial fields.They are usually machined by CNC machine tools,but recently have also begun to be manufactured by industrial robotic arm manipulators,thanks to low cost,large operation reaching space and high machining flexibility of robot.So far,various methodologies have been proposed to improve efficiency and quality of free-form surface machining,thus this paper aims at providing a state-ofthe-art review on research advances in free-form surface machining.In this review,tool path generation,feedrate scheduling in Cartesian space and trajectory planning in joint space are focused for both CNC machining and robot machining,and their research statues,existing difficulties and key issues are discussed in detail.Finally,the feasible routes,breakthrough points and future development trend are also expounded. 展开更多
关键词 CNC machining Feedrate Free-form surface Robotic machining Tool path Trajectory
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Accurate Evaluation of Free-form Surface Profile Error Based on Quasi Particle Swarm Optimization Algorithm and Surface Subdivision 认领 引用 被引量：14
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作者 WEN Xiulan ZHAO Yibing +2 位作者 WANG Dongxia ZHU Xiaochun XUE Xiaoqiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第2期406-413,共8页
Although significant progress has been made in precision machining of free-form surfaces recently, inspection of such surfaces remains a difficult problem. In order to solve the problem that no specific standards for ... Although significant progress has been made in precision machining of free-form surfaces recently, inspection of such surfaces remains a difficult problem. In order to solve the problem that no specific standards for the verification of free-form surface profile are available, the profile parameters of free-form surface are proposed by referring to ISO standards regarding form tolerances and considering its complexity and non-rotational symmetry. Non-uniform rational basis spline（NURBS） for describing free-form surface is formulated. Crucial issues in surface inspection and profile error verification are localization between the design coordinate system（DCS） and measurement coordinate system（MCS） for searching the closest points on the design model corresponding to measured points. A quasi particle swarm optimization（QPSO） is proposed to search the transformation parameters to implement localization between DCS and MCS. Surface subdivide method which does the searching in a recursively reduced range of the parameters u and v of the NURBS design model is developed to find the closest points. In order to verify the effectiveness of the proposed methods, the design model is generated by NURBS and the measurement data of simulation example are generated by transforming the design model to arbitrary position and orientation, and the parts are machined based on the design model and are measured on CMM. The profile errors of simulation example and actual parts are calculated by the proposed method. The results verify that the evaluation precision of freeform surface profile error by the proposed method is higher 10%-22% than that by CMM software. The proposed method deals with the hard problem that it has a lower precision in profile error evaluation of free-form surface. 展开更多
关键词 profile error evaluation free-form surface quasi particle swarm optimization surface subdivision
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An automatic grid generation approach over free-form surface for architectural design 认领 引用 被引量：16
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作者 苏亮 祝顺来 +1 位作者 肖南 高博青 《Journal of Central South University》 SCIE EI CAS 2014年第6期2444-2453,共10页
An essential step for the realization of free-form surface structures is to create an efficient structural gird that satisfies not only the architectural aesthetics,but also the structural performance.Employing the ma... An essential step for the realization of free-form surface structures is to create an efficient structural gird that satisfies not only the architectural aesthetics,but also the structural performance.Employing the main stress trajectories as the representation of force flows on a free-form surface,an automatic grid generation approach is proposed for the architectural design.The algorithm automatically plots the main stress trajectories on a 3D free-form surface,and adopts a modified advancing front meshing technique to generate the structural grid.Based on the proposed algorithm,an automatic grid generator named "St-Surmesh" is developed for the practical architectural design of free-form surface structure.The surface geometry of one of the Sun Valleys in Expo Axis for the Expo Shanghai 2010 is selected as a numerical example for validating the proposed approach.Comparative studies are performed to demonstrate how different structural grids affect the design of a free-form surface structure. 展开更多
关键词 grid generation free-form surface structure architectural geometry stress trajectory advancing front meshing technique
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Tool-path planning for free-form surface high-speed high-resolution machining using torus cutter 认领 引用 被引量：1
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作者 王宇晗 李儒琼 +1 位作者 吴祖育 陈兆能 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第3期337-342,共6页
In CNC machining, two essential components decide the accuracy and machining time for a sculptured surface: one is the step-size interval, the other is the tool-path interval. Due to the limitation of the conventional... In CNC machining, two essential components decide the accuracy and machining time for a sculptured surface: one is the step-size interval, the other is the tool-path interval. Due to the limitation of the conventional method for calculating the tool-path interval, it cannot satisfy the machining requirement for high-speed and high-resolution machining. Accordingly, for high-speed and high-resolution machining, the current study proposes a new tool-path interval algorithm, plus a variable step-size algorithm for NURBS. Furthermore, a new type cutter, which can improve the cutting efficiency, is investigated in the paper. The transversal equation of the torus cutter onto the flat plan is given in this paper. The tool-path interval is calculated with the transversal equation and the proposed algorithm. The illustrated example shows that the redundant tool paths can be reduced because an accurate tool-path interval could be calculated. 展开更多
关键词 high-speed machining tool-path planning free-form surface torus cutter
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NEW VISUAL METHOD FOR FREE-FORM SURFACE RECONSTRUCTION 认领 引用 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》 EI CAS 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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Tool selection and collision-free in 5-axis numerical control machining of free-form surfaces 认领 引用
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作者 杨长祺 QIN Datong 《Journal of Chongqing University》 2002年第2期20-23,共4页
The methodology of 5-axis cutter selection to avert collision for free-form surface machining by flat-end cutters is presented. The combination of different cutters is adopt aiming at short machining time and high pre... The methodology of 5-axis cutter selection to avert collision for free-form surface machining by flat-end cutters is presented. The combination of different cutters is adopt aiming at short machining time and high precision. The optimal small cutter is determined based on the geometric information of the points where a cutter most probably collide with the machined surface. Several larger cutters are selected to machine the surface in order to find the interference-free area. The difference of machining time for this area between the optimal small cutter and the large cutters is calculated. The functional relationship between the machining time and the radius of a cutter is established, by which the optimal number of cutters is obtained. The combination of cutters, which possesses the minimum overall machining time, is selected as the optimal cutter sizes. A case study has demonstrated the validity of the proposed methodology and algorithms. 展开更多
关键词 optimal tool selection collision-free tool path generation free-form surfaces flat-end cutter
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Parametric design of a part with free-form surfaces 认领 引用 被引量：3
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作者 KIM Yeoung-il KIM Li-ra JUN Cha-soo 《Journal of Zhejiang University-SCIENCE A》 EI CAS 2006年第9期1530-1534,共5页
3D solid models for parts with regular-form surfaces (PRFSs) are effectively generated using traditional parametric design techniques. A new model is obtained by changing some parameters defining the model. The parts ... 3D solid models for parts with regular-form surfaces (PRFSs) are effectively generated using traditional parametric design techniques. A new model is obtained by changing some parameters defining the model. The parts with free-form surfaces (PFFSs), however, cannot be defined by several parameters. Usually they are defined by some geometric elements like profile curves. The traditional parametric design approaches have not easily dealt with the PFFSs. A method for generating a solid model and an engineering drawing for PFFSs is proposed in this paper: First, the new profiles are generated from input point data. Second, the profile information is extracted from the existing model. Last, the old profiles are replaced with the new profiles. This method can preserve the associative information of the existing model and automatically generate the drawing including views, dimen- sions, and annotations. The proposed method has been implemented using a commercial CAD/CAM system, Unigraphics, and API functions written in C-language, and were applied to the blades of a turbine generator. Some illustrative examples are pro- vided in order to show the effectiveness of the proposed method. 展开更多
关键词 Parametric modelling Free-form surface Solid model Drawing
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ADAPTIVE MEASUREMENT METHOD BASED ON CHANGING-CURVATURE FOR UNKNOWN FREE-FORM SURFACE 认领 引用 被引量：1
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作者 WuShixiong WangWen ChenZichen 《Chinese Journal of Mechanical Engineering》 EI CAS 2004年第3期385-388,共4页
Current measurement method for unknown free-form surface has low efficiency.To acquire given precision, a lot of null points are measured. Based on change surface curvature, anew measurement planning is put forward. S... Current measurement method for unknown free-form surface has low efficiency.To acquire given precision, a lot of null points are measured. Based on change surface curvature, anew measurement planning is put forward. Sample step is evaluated from the change curvature and thelocally-bounded character of extrapolating curve. Two coefficients, maximum error coefficient andlocal camber coefficient, are used to optimize sampling step. The first coefficient is computed toavoid sampling-point exceeding the measurement range and the second control sampling precision.Compared with the other methods, the proposed planning method can reduce the number of themeasuring-point efficiently for the given precision. Measuring point distributes adaptively by thechange surface curvature. The method can be applied to improve measurement efficiency and accuracy. 展开更多
关键词 Free-form surface Adaptive sampling Curvature
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STUDY OF NON-CONTACT MEASUREMENT OF FREE-FORM SURFACES 认领 引用
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作者 徐玉春 张国雄 +2 位作者 解则晓 冯国馨 王春海 《Transactions of Tianjin University》 CAS 2001年第4期226-228,共3页
A non contact three dimensional measurement method is presented in this paper.This system consists of a laser triangulation probe,a probe head and a coordinate measuring machine (CMM).The measurement principle of the ... A non contact three dimensional measurement method is presented in this paper.This system consists of a laser triangulation probe,a probe head and a coordinate measuring machine (CMM).The measurement principle of the system is discussed,and a system calibration method employing a reference ball is proposed.The geometric model involving four frames is established to calculate the data points based on the reading of the laser probe and position information from the CMM.A measuring experiment for gesso free form surface using this system is carried out. 展开更多
关键词 free form surface coordinate measuring machine PH10 probe head laser triangulation probe calibration
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A Computer Vision Method for 3D Reconstruction of Curves-Marked Free-Form Surfaces 认领 引用 被引量：1
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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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Information Construction Technology of Free-Form Surface Steel Grid 认领 引用
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作者 Tong Lu Ying Liu +3 位作者 Shuai Wang Ke-yang Wu Jin Xia Bang-feng Xi 《Journal of Architectural Research and Development》 2022年第4期23-29,共7页
Taking the construction project of National Network Security Talents and Innovation Base Exhibition Center as an example,the application of building information model in the construction process of free-form surface s... Taking the construction project of National Network Security Talents and Innovation Base Exhibition Center as an example,the application of building information model in the construction process of free-form surface steel structure is analyzed in this paper.The results show that the application of Building Information Modeling(BIM)technology to the construction of free-form surface structure improves the work efficiency of the construction team in multi-disciplinary collaboration,surface component manufacturing,and construction process design,and subsequently improves the construction speed and construction quality. 展开更多
关键词 BIM Free surface Steel structure Construction technology Informationization
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ADAPTIVE STRATEGIES FORNC MACHINING COMPOUND FREE-FORM SURFACES 认领 引用
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作者 Gao Sande Zhou Yunfei +1 位作者 Zhang Xinfang Zhou Ji 《Computer Aided Drafting,Design and Manufacturing》 1994年第2期59-65,共7页
This paper treats adaptation to the machining precision and productivity of compound free-form surfaces. The principle of a mixed NC machining method (surface direct interpolating (SDI[1])and discrete NC programming) ... This paper treats adaptation to the machining precision and productivity of compound free-form surfaces. The principle of a mixed NC machining method (surface direct interpolating (SDI[1])and discrete NC programming) is introduced- Three adaptive procedures are discussed : ( 1 ) adaptivedivision of the machining areas, (2) adaptive triangulation for generating interference-free tool pathsfrom compound surfaces, (3) machining along surface/surface intersection (SSI ) curves with anadaptive step length. They upgrade the intelligence of machining compound surfaces. 展开更多
关键词 compound surface NC machining adaptive triangulation adaptive step length
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Research on the Fault Monitoring System in Free-form Surface CNC Machining Based on Wavelet Analysis 认领 引用
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作者 XU Shu-xin 1, ZHAO Ji 2, ZHAN Jian-ming 1, LE Guan 1 (1. College of Mechanical Science and Engineering, Jilin University, Changchun 130022, China 2. Office of Education Administration, Jilin University, Changchun 130012, Chi na) 《厦门大学学报（自然科学版）》 CAS 北大核心 2002年第S1期72-73,共2页
Carrying out experiments and researches on tool bre ak age and undercut of work-piece of free-form surface by using wavelet analysis, both the fault features can be extracted in a special frequency segment of wave let... Carrying out experiments and researches on tool bre ak age and undercut of work-piece of free-form surface by using wavelet analysis, both the fault features can be extracted in a special frequency segment of wave let decompose. According to the feature of transient fault, the author proposes for the first time the automatic determination technology of the threshold by us e of the adaptive filter characteristic of wavelet transform. Based on profound researches on steady fault feature, this dissertation makes an effective token o f steady fault feature by using wavelet energy method, and proposes the new idea to identify cut-in case and cut-out case, thereby successfully gives an uniqu e description quantitatively on the characterization of the variation of fault a nd cutting condition in the monitoring system. 展开更多
关键词 wavelet analysis free-form surfaces CNC mach ining monitoring system
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Study of the Contact Force in Free-form Surfaces Compliant EDM Polishing by Robot 认领 引用 被引量：2
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作者 ZHAN Jian-ming 1, ZHAO Ji 2, XU Shu-xin 1, ZHU Pei-xi ng 1 (1. College of Mechanical Science and Engineering, Jilin University, Changchun 130022, China 2. Office of Education Administration, Jilin University, Changchun 130012, Chin a) 《厦门大学学报（自然科学版）》 CAS 北大核心 2002年第S1期
With an elastic negative pole being driven by ultra so nic vibration and being moved along the surface of work-piece compliantly by ro bot, a new kind of effective EDM, the compliant EDM, cuts the electrically condu c... With an elastic negative pole being driven by ultra so nic vibration and being moved along the surface of work-piece compliantly by ro bot, a new kind of effective EDM, the compliant EDM, cuts the electrically condu ctive materials away and polishes work-piece of free-form surface. The study o f the contact force between the end of polishing tool and the surface of work-p iece is the key for the compliant EDM to study its cutting mechanism and to make better use of it. This paper makes a model for the contact force and verifies i t by experiments and simulation based on the theory of elastic body kinetics and dynamic stress concentration. The research work shows that this contact force i s caused by both the electrical impulsion of EDM and the mechanical force of ult rasonic vibration, the discharge frequency of compliant EDM has a much more clos er connection with the vibration frequency of polishing tool rather than the fre quency of ultrasonic vibration. 展开更多
关键词 robot compliant EDM polishing free-form surfac es contract force
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Seasonal contrasts in recent Arctic warming processes: surface air temperature versus surface temperature 认领 引用 被引量：1
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作者 CAI Ziyi WU Fangying +3 位作者 OUYANG Huiling YOU Qinglong Sergey K.GULEV Seok-Woo SON 《Advances in Polar Science》 CSCD 2026年第2期182-199,共18页
Arctic warming has been widely documented, yet the relative contributions of processes controlling surface air temperature(SAT) and surface temperature(ST) warming remain insufficiently quantified, particularly betwee... Arctic warming has been widely documented, yet the relative contributions of processes controlling surface air temperature(SAT) and surface temperature(ST) warming remain insufficiently quantified, particularly between warm and cold seasons. Here, we use multiple reanalysis datasets to quantify Arctic SAT and ST warming from 1979 to 2021 through thermodynamic and surface energy budget analyses, with a focus on the seasonal contrast between warm season and cold season. We show that SAT warming in both seasons is primarily linked to an increase in the diabatic heating residual associated with surface warming, whereas cold season SAT warming is additionally enhanced by strengthened warm advection, which accounts for 33% of the total SAT increase. ST warming exhibits a stronger seasonal contrast. In the warm season, ST warming is driven jointly by enhanced downward longwave radiation, mainly associated with increased atmospheric water vapor, and sea ice albedo feedback, contributing 27% and 33% of the ST increase, respectively. In the cold season, ST warming is dominated by enhanced downward longwave radiation, with atmospheric water vapor, mid-level cloud cover, and a residual term mainly related to external greenhouse gas forcing contributing 36%, 16%, and 10%, respectively. The Arctic Ocean further modulates this seasonality by absorbing heat in the warm season and releasing it in the cold season, contributing 21% to cold season ST warming and providing an additional heat source for the lower atmosphere. These results demonstrate that recent Arctic warming cannot be interpreted from SAT or ST alone, but reflects seasonally distinct coupling among atmospheric heat transport, radiative feedbacks, sea ice loss, and ocean heat storage and release. 展开更多
关键词 Arctic warming process quantitative contribution surface energy budget
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Depression induces ocular surface inflammation and dry eye-like changes in mice 认领 引用 被引量：1
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作者 Xiang Lin Yu-Wen Liu +7 位作者 Jia-Ni Li Wei-Jie Ouyang Li-Ying Tang Jie-Li Wu Zhao-Lin Liu Shi-Nan Wu Jiao-Yue Hu Zu-Guo Liu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2026年第3期434-442,共9页
AIM:To investigate the impact of depression-like behavior on ocular surface homeostasis in a mouse model,with a focus on dry eye-like alterations.METHODS:Male C57BL/6J mice(10-12 weeks old)were randomly assigned to co... AIM:To investigate the impact of depression-like behavior on ocular surface homeostasis in a mouse model,with a focus on dry eye-like alterations.METHODS:Male C57BL/6J mice(10-12 weeks old)were randomly assigned to control or restraint stress(RS)groups.The RS group underwent three intermittent 24-hour restraint sessions to induce depressive-like behavior.Behavioral testing,tear secretion measurement,and corneal Oregon Green Dextran(OGD)staining were performed.Postmortem analyses included histological evaluation of lacrimal glands,goblet cell quantification using periodic acid-Schiff staining,and assessment of key inflammatory and apoptotic markers:interleukin(IL)-17,matrix metalloproteinases(MMP)-3,MMP-9,IL-13,interferon(IFN)-γ,and cleaved caspase-3 and-8.RESULTS:Repeated RS induced depression-like behavior and significant ocular surface changes.RStreated mice showed increased corneal OGD uptake and upregulation of gene/protein expression of IL-17,MMP-3,and MMP-9(P<0.05).Goblet cell density and IL-13 protein expression were reduced,while IFN-γprotein expression was elevated(P<0.05).Cleaved caspase-3 and-8 levels were significantly increased in both cornea and conjunctiva.Tear volume and lacrimal gland size were unchanged;however,mild inflammatory infiltration was observed in lacrimal glands.CONCLUSION:Repeated RS leads to ocular surface inflammation and dry eye-like pathology,including corneal barrier disruption,goblet cell loss,and epithelial apoptosis.These findings suggest that depression contributes to the pathogenesis of dry eye disease via immune-mediated mechanisms. 展开更多
关键词 depression restraint stress dry eye ocular surface damage inflammation mice
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Surface reconstruction via rapid solution quenching to enhance structural stability of lithium-rich layered cathodes 认领 引用 被引量：1
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作者 Hailiang Chu Jiaxiao Meng +4 位作者 Longde Duan Shujun Qiu Errui Wang Fen Xu Lixian Sun 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2026年第5期1553-1563,I0092-I0106,共11页
Lithium-rich layered oxides are prospective materials for future-generation cathodes attributable to their high specific capacity.However,significant surface instability,particularly under high-voltage operating condi... Lithium-rich layered oxides are prospective materials for future-generation cathodes attributable to their high specific capacity.However,significant surface instability,particularly under high-voltage operating conditions,leads to substantial voltage decay and dramatic capacity degradation during long-term cycling,severely limiting their widespread application.In this study,we developed a universal brine quenching strategy to construct a stabilized composite surface structure for lithium-rich layered oxides.This structure comprises an inner surface layer with a Y-doped layered structure and an outermost layer featuring a disordered rock-salt structure.Doping in the layered structure strengthens the Y-O bonds,raises the energy barrier for oxygen evolution,and significantly increases the stability of the lattice oxygen.Additionally,the disordered rock-salt surface structure reduces oxygen release during the charge and discharge cycles.Consequently,this well-designed surface structure significantly boosts the structural stability of the lithium-rich layered oxide surface,suppresses structural degradation during long-term cycling,and facilitates Li+diffusion kinetics.The improved redox activity,combined with superior structural stability,contributes to an outstanding electrochemical performance.For instance,the Y-quenched Li1.2Mn0.54Ni0.13Co0.13O2(LLO)cathode exhibited an improved discharge capacity of 283 mAh·g-1at 0.1 C and 223 mAh·g-1at 1 C,along with remarkable cyclic stability retaining 91.2% of its capacity after 300 cycles at 1 C,and a reduced voltage decay of 0.76 mV per cycle(compared to 1.16 mV per cycle for pristine LLO).This research provides valuable insights into the design and synthesis of high-energydensity lithium-rich layered oxides through a simple and cost-effective strategy. 展开更多
关键词 Li-rich layered oxides brine quenching surface structure voltage decay cycling stability
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Probing high-order deformation effects in neutron-deficient nuclei246,248No with improved potential-energy-surface calculations 认领 引用 被引量：1
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作者 Jin-Liang Guo Hua-Lei Wang +2 位作者 Kui Xiao Zhen-Zhen Zhang Min-Liang Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第3期143-152,共10页
The high-order deformation effects in even-even246,248No are investigated by means of pairing self-consistent WoodsSaxon-Strutinsky calculations using the potential-energy-surface(PES)approach in an extended deform... The high-order deformation effects in even-even246,248No are investigated by means of pairing self-consistent WoodsSaxon-Strutinsky calculations using the potential-energy-surface(PES)approach in an extended deformation space(β2,β3,β4,β5,β6,β7,β8).Based on the calculated two-dimensional projected energy maps and different potential energy curves,we found that the highly even-order deformations have an important impact on both the fission trajectory and energy minima,while the odd-order deformations,accompanying the even-order ones,primarily affect the fission path beyond the second barrier.Relative to the light actinide nuclei,the nuclear ground state changes to the superdeformed configuration,but the normally deformed minimum,as the low-energy shape isomer,may still be primarily responsible for enhancing nuclear stability and ensuring experimental accessibility in246,248No.Our present investigation indicates the nonnegligible impact of high-order deformation effects along the fission valley and will be helpful for deepening the understanding of different deformation effects and deformation couplings in nuclei,especially in this neutron-deficient heavy-mass region. 展开更多
关键词 High-order deformations Neutron-deficient nuclei Potential energy surface Nuclear stability Macroscopic–microscopic model
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Cooperative Pursuit of Unmanned Surface Vehicles Using Multi-Agent Reinforcement Learning 认领 引用 被引量：1
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作者 QU Xingru LI Chu +2 位作者 JIANG Yuze LONG Feifei ZHANG Rubo 《Journal of Shanghai Jiaotong university(Science)》 EI 2026年第1期187-194,共8页
This paper is concerned with the cooperative pursuit of unmanned surface vehicles(USVs)against the dynamic escaping target using multi-agent reinforcement learning.The Markov game process is established for pursuit-ev... This paper is concerned with the cooperative pursuit of unmanned surface vehicles(USVs)against the dynamic escaping target using multi-agent reinforcement learning.The Markov game process is established for pursuit-evasion,and the success criteria for cooperative capture of USVs are given by using distance and angle constraints.By virtue of the centralized training and decentralized execution framework as well as the long short-term memory network,cooperative pursuit training is conducted using the multi-agent soft actor-critic reinforcement learning,which can optimize capture performance of USVs against the escaping target.Besides,to avoid the occurrence of lazy capturer and increase the capture success rate,a multi-stage reward guidance method is developed,where the training process can be optimized according to the current states of both sides,effectively guiding vehicle to achieve the capture task from easy to difficult.Simulations are provided to illustrate the effectiveness of the proposed reinforcement learning method for cooperative pursuit of USVs. 展开更多
关键词 unmanned surface vehicle(USV) cooperative pursuit multi-agent soft actor-critic multi-stage reward
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Switching the Droplet Rebound Direction on Anisotropic Surfaces by Manipulating the Wetting State 认领 引用 被引量：1
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作者 Shuo-Yan Zhang Jian-Gang Guo 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2026年第4期552-562,共11页
Droplet rebound is a key topic in interfacial physics and fluid mechanics,with important applications in industry,energy,and biomedicine.Based on the principle of energy conservation,a theoretical model was developed ... Droplet rebound is a key topic in interfacial physics and fluid mechanics,with important applications in industry,energy,and biomedicine.Based on the principle of energy conservation,a theoretical model was developed to describe droplet rebound on anisotropic superhydrophobic surfaces,providing functional relationships between the rebound direction and velocity of the droplet and the structural characteristic parameters.Combined with numerical simulations and experimental characterization,it was found that a stable Cassie state reduces energy dissipation during the droplet spreading and rebound process,facilitating low energy rebound.Moreover,under different parameter conditions,droplets can exhibit completely opposite motion on anisotropic surfaces.With the increase of the proportion of structures in the Wenzel wetting state,the droplet rebound direction gradually shifts from opposite to the structural inclination to the same direction.Furthermore,the droplet spreading and rebound process is primarily influenced by the droplet’s initial state and the surface compressive stability.Through force-material optimized design,the fabricated biomimetic surface enables droplets to maintain a Cassie state with minimal energy dissipation even at We=18,reducing the required Weber number by 35%compared with the rebound distance in the Wenzel state.This study further refines the mechanical model of droplet rebound,addressing challenges such as the precise control of droplet motion. 展开更多
关键词 Droplet rebound Anisotropic surface Wetting state Structural design
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