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A survey of deep learning-based 3D shape generation

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Computational Visual Media 2023年第3期9卷 407-442页

作者： Qun-Ce Xu Tai-Jiang Mu yong-liang yang BNRist Department of Computer Science and TechnologyTsinghua UniversityBeijing 100084China Department of Computer Science University of BathBathUK

Deep learning has been successfully used for tasks in the 2D image *** on 3D computer vision and deep geometry learning has also attracted *** achievements have been made regarding feature extraction and discrimination of 3D *** recent advances in deep generative models such as generative adversarial networks,effective generation of 3D shapes has become an active research *** 2D images with a regular grid structure,3D shapes have various representations,such as voxels,point clouds,meshes,and implicit *** deep learning of 3D shapes,shape representation has to be taken into account as there is no unified representation that can cover all tasks *** such as the representativeness of geometry and topology often largely affect the quality of the generated 3D *** this survey,we comprehensively review works on deep-learning-based 3D shape generation by classifying and discussing them in terms of the underlying shape representation and the architecture of the shape *** advantages and disadvantages of each class are further *** also consider the 3D shape datasets commonly used for shape ***,we present several potential research directions that hopefully can inspire future works on this topic.

关键词： 3D representations geometry learning generative models deep learning

Quasi-steady aerodynamic characteristics of Terminal Sensitive Bullets with short cylindrical portion

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Defence Technology（防务技术） 2021年第2期17卷 633-649页

作者： yong-liang yang Rui Guo Rong-zhong Liu liang Chen Bo-yang Xing Bo-bo Zhao School of Mechanical Engineering Nanjing University of Science and TechnologyXiaolingwei 200210094NanjingChina The Seventh Design Department Aerospace Science and Technology CorporationThe Seventh Research Institute610100ChengduChina Unit 31102 of PLA 210000NanjingChina

The aerodynamic characteristics are vital for short cylindrical Terminal Sensitive Bullets(TSB)with lowaspect ratio,especially in terminal ***,there is little research in terms of the TSB andshort cylinder with two free ends,and particularly in this trajectory,where the scanning angleβand rollangle a vary over a broad range between 0°and *** this work wind tunnel experiments are firstconducted to learn the effects of Reynolds number and scanning angle on aerodynamic parameters forshort cylinder with aspect ratio L/D=*** to infinite cylinder,for the short cylinder with two freeends,the drag crisis phenomenon still exists in the critical regime 1.7×10^(5)≤Re≤6.8×10^(5).Then 3Dsimulations are performed to demonstrate the aerodynamic characteristics of short cylinder and TSBover a broad range of Re,L/D,a and *** sensitivity analysis of time step and grid are presented as ***β3=0,for short cylinder,the drag crisis phenomenon was also observed in the simulation,but notas obvious as in the wind tunnel *** some attitudes,there is an obvious Karman vortexin the wake ofshort cylinder and *** correlation between time-averaged aerodynamic coefficients and L/D,Re,a&l is *** vortex shedding frequency and shear layer behavior are obtained for quasi-steadyand unsteady ***,the effect of end's shape on drag reduction and vortex shedding frequency isanalyzed.

关键词： Turbulent flows around bluff body Critical regime Flow-induced structural vibration

Influence of the embedded structure on the EFP formation of compact terminal sensitive projectile

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Defence Technology（防务技术） 2017年第4期13卷 310-315页

作者： Bo-yang Xing Rong-zhong Liu Rui Guo liang Chen Hao Zhou yong-liang yang Lei Liu School of Mechanical Engineering Nanjing University of Science and Technology Faculty of Engineering University of Nottingham Department of Mechanical Engineering Eindhoven University of Technology

To improve the damage efficiency of compact terminal sensitive projectile with EFP warhead,it is vital to understand how the embedded structure(ES)affects the EFP forming *** this paper,the corresponding numerical investigation is focused on,in which the fluid-structure interaction(FSI)method and the experimental verification are *** on the obtained quantitative relations between the forming performance and a(the ratio of height to maximum radius of ES),an optimal design is further *** results indicate that:when the embedded structural length and width range 0.1e0.3D and 0.1e0.2D(D:diameter of EFP warhead)at a fixed volume,respectively,EFP forming velocity nearly keeps as a constant,1760 m/s;the height of ES has a dramatical effect on the propagating range of detonation wave,resulting in significant influence on the aerodynamic shape and length-to-diameter ratio of EFP;under the given constraints,the EFP length-diameter ratio can reach the optimal value2.76,when the height of ES is 0.22D.

关键词： Terminal sensitive projectile Embedded structure Detonation wave EFP formation

Fitting quadrics with a Bayesian prior

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Computational Visual Media 2016年第2期2卷 107-117页

作者： Daniel Beale yong-liang yang Neill Campbell Darren Cosker Peter Hall University of Bath

Quadrics are a compact mathematical formulation for a range of primitive surfaces. A problem arises when there are not enough data points to compute the model but knowledge of the shape is available. This paper presents a method for fitting a quadric with a Bayesian prior. We use a matrix normal prior in order to favour ellipsoids when fitting to ambiguous data. The results show the algorithm copes well when there are few points in the point cloud,competing with contemporary techniques in the area.

关键词： geometry statistics graphics computer vision

Minimally invasive open reduction of greater tuberosity fractures by a modified suture bridge procedure

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World Journal of Clinical Cases 2022年第1期10卷 117-127页

作者： Ling-Peng Kong Juan-Juan yang Fu Wang Fan-Xiao Liu yong-liang yang Department of Orthopaedics Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021Shandong ProvinceChina Department of Radiotherapy Shandong Cancer Hospital and InstituteShandong First Medical University and Shandong Academy of Medical SciencesJinan 250117Shandong ProvinceChina

BACKGROUND Most greater tuberosity fractures can be treated without surgery but some have a poor *** surgical procedures for avulsion fractures of the humeral greater tuberosity include screw fixation,suture anchor fixation,and plate fixation,all of which have treatment-associated *** decrease surgical complications,we used a modified suture bridge procedure under direct vision and a minimally invasive small incision to fix fractures of the greater tuberosity of the *** To investigate the clinical efficacy and outcomes of minimally invasive modified suture bridge open reduction of greater tuberosity evulsion *** Sixteen patients diagnosed between January 2016 and January 2019 with an avulsion-type greater tuberosity fracture of the proximal humerus and treated by minimally invasive open reduction and modified suture bridges with anchors were studied *** were followed up by clinical examination and radiographs at 3 and 6 wk,3,6 and 12 mo after surgery,and thereafter every 6 *** were assessed preoperatively and postoperatively by a visual analog scale(VAS),the University of California Los Angeles(UCLA)shoulder score,the American Shoulder and Elbow Surgeon score(ASES),and range of motion(ROM)for *** Seven men and nine women,with an average age of 44.94 years,were *** time between injury and surgery was 1-2 d,with an average of 1.75 *** mean operation time was 103.1±7.23 *** patients achieved bone union within 3 mo after *** scores were significantly decreased(P=0.002),and the mean degrees of forward elevation(P=0.047),mean degrees of abduction(P=0.035),ASES score(P=0.092)were increased at 3 *** UCLA score was increased at 6 wk(P=0.029)after *** average degrees of external rotation and internal rotation both improved at 3 mo after surgery(P=0.012 and P=0.007,respectively).No procedure-related deaths or incision-related superficial or deep tissue infectio

关键词： Minimally invasive Greater tuberosity fracture Open reduction Suture bridge Anchor

3D computational modeling and perceptual analysis of kinetic depth effects

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Computational Visual Media 2020年第3期6卷 265-277页

作者： Meng-Yao Cui Shao-Ping Lu Miao Wang yong-liang yang Yu-Kun Lai Paul L.Rosin TKLNDST CSNankai UniversityTianjinChina State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijingChina Department of Computer Science University of BathUK School of Computer Science and Informatics Cardiff UniversityWalesUK

Humans have the ability to perceive kinetic depth effects, i.e., to perceived 3 D shapes from 2 D projections of rotating 3 D objects. This process is based on a variety of visual cues such as lighting and shading effects. However, when such cues are weak or missing, perception can become faulty, as demonstrated by the famous silhouette illusion example of the spinning dancer. Inspired by this, we establish objective and subjective evaluation models of rotated3 D objects by taking their projected 2 D images as input. We investigate five different cues: ambient luminance, shading, rotation speed, perspective, and color difference between the objects and *** the objective evaluation model, we first apply3 D reconstruction algorithms to obtain an objective reconstruction quality metric, and then use quadratic stepwise regression analysis to determine weights of depth cues to represent the reconstruction quality. In the subjective evaluation model, we use a comprehensive user study to reveal correlations with reaction time and accuracy, rotation speed, and perspective. The two evaluation models are generally consistent, and potentially of benefit to inter-disciplinary research into visual perception and 3 D reconstruction.

关键词： rotation spinning rotating

SIZE EXCLUSION CHROMATOGRAPHIC COLUMN PACKED WITH REGENERATED CELLULOSE GELS

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Chinese Journal of Polymer Science 2001年第4期19卷 415-419页

作者： Guang yang Li-na Zhang Xiao-peng Xiong Xiao-dong Cao yong-liang yang Department of Chemistry Wuhan University Wuhan 430072, China 武汉大学湖北武汉

Microporous regenerated cellulose gel particles were prepared by mixing cellulose cuoxam with silk fibroin as pore former, and the mean pore size and pore volume of the particles were 525 nm and 7.27 mt g(-1), respectively. A preparative size-exclusion chromatography (SEC) column (550 mm x 20 mm) packed with the cellulose gel particles was used for the fractionation of two polysaccharides Dextran 07 (M-W = 7.14 x 10(4), d = 1.7) and Dextran 50 (M-W = 50.5 x 10(4), d = 3.8) in water phase. The fractionation range of the stationary phase covered M, from 3 x 10(3) to 1.1 x 10(6). The daily throughput was 2.9 g for Dextran 07 (D07) and 4.3 g for Dextran 50 (D50) with a flow-rate of 1.5 mt min(-1). The fractions obtained by using the SEC were analyzed by an analytical SEC combined with laser light scattering (LLS), and the polydispersity indices of fractions for Dextran 07 and Dextran 50 were determined to be 1.34-1.57 and 1.53-3.36, respectively. The preparative SEC is a simple, rapid, and suitable means not only for the fractionation of polysaccharides in water but also for other polymers in organic solvents.

关键词： cellulose packing silk fibroin preparative chromatography polysaccharides

Magneto‑Dielectric Synergy and Multiscale Hierarchical Structure Design Enable Flexible Multipurpose Microwave Absorption and Infrared Stealth Compatibility

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Nano-Micro Letters 2025年第2期17卷 401-416页

作者： Chen Li Leilei liang Baoshan Zhang Yi yang Guangbin Ji School of Electronic Science and Engineering Nanjing UniversityNanjing 210093People’s Republic of China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration ***,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption *** top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass ***,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric *** theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ***,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of ***,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments.

关键词： Microwave absorption Radar-infrared compatible stealth Wrinkled MXene Magneto-dielectric synergy Multifunction

IoT Empowered Early Warning of Transmission Line Galloping Based on Integrated Optical Fiber Sensing and Weather Forecast Time Series Data

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Computers, Materials & Continua 2025年第1期82卷 1171-1192页

作者： Zhe Li Yun liang Jinyu Wang yang Gao State Grid Henan Electric Power Company Electric Power Scientific Research Institute State Grid Henan Electric Power CompanyZhengzhou450052China

Iced transmission line galloping poses a significant threat to the safety and reliability of power systems,leading directly to line tripping,disconnections,and power *** early warning methods of iced transmission line galloping suffer from issues such as reliance on a single data source,neglect of irregular time series,and lack of attention-based closed-loop feedback,resulting in high rates of missed and false *** address these challenges,we propose an Internet of Things(IoT)empowered early warning method of transmission line galloping that integrates time series data from optical fiber sensing and weather ***,the method applies a primary adaptive weighted fusion to the IoT empowered optical fiber real-time sensing data and weather forecast data,followed by a secondary fusion based on a Back Propagation(BP)neural network,and uses the K-medoids algorithm for clustering the fused ***,an adaptive irregular time series perception adjustment module is introduced into the traditional Gated Recurrent Unit(GRU)network,and closed-loop feedback based on attentionmechanism is employed to update network parameters through gradient feedback of the loss function,enabling closed-loop training and time series data prediction of the GRU network ***,considering various types of prediction data and the duration of icing,an iced transmission line galloping risk coefficient is established,and warnings are categorized based on this ***,using an IoT-driven realistic dataset of iced transmission line galloping,the effectiveness of the proposed method is validated through multi-dimensional simulation scenarios.

关键词： Optical fiber sensing multi-source data fusion early warning of galloping time series data IoT adaptive weighted learning irregular time series perception closed-loop attention mechanism