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Cooperative Sensing and Distributed Control of a Diffusion Process Using Centroidal Voronoi Tessellations

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Numerical Mathematics(Theory,Methods and Applications) 2010年第2期3卷 162-177页

作者： haiyang Chao yang-Quan Chen Center for Self Organizing and Intelligent Systems Electrical and Computer Engineering Department Utah State University Logan UT 84322 USA.

This paper considers how to use a group of robots to sense and control a diffusion *** diffusion process is modeled by a partial differential equation (PDE),which is a both spatially and temporally variant *** robots can serve as mobile sensors,actuators,or *** Voronoi Tessellations based coverage control algorithm is proposed for the cooperative sensing *** the diffusion control problem,this paper considers spraying control via a group of networked mobile robots equipped with chemical neutralizers,known as smart mobile sprayers or actuators,in a domain of interest having static mesh sensor network for concentration *** paper also introduces the information sharing and consensus strategy when using centroidal Voronoi tessellations algorithm to control a diffusion *** information is shared not only on where to spray but also on how much to spray among the mobile *** from using CVT and information consensus seeking for sensing and control of a diffusion process are demonstrated in simulation results.

关键词： Consensus centroidal Voronoi tessellations diffusion process distributed control mobile actuator and sensor networks.

基于多视图融合与多特征提取的知识图谱补全方法

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数据分析与知识发现 2025年第1期9卷 79-89页

作者：谢珺杨海洋续欣莹程兰张亚睿吕佳琪太原理工大学电子信息与光学工程学院晋中030600 太原理工大学电气与动力工程学院太原030024

【目的】针对现有知识图谱补全模型知识表示质量低、模型性能差等问题,提出一种基于多视图融合与多特征提取的知识图谱补全方法。【方法】通过视图编码器生成多个单视图网络,利用注意力机制融合不同视图信息作为实体的最终知识表示;通... 详细信息

【目的】针对现有知识图谱补全模型知识表示质量低、模型性能差等问题,提出一种基于多视图融合与多特征提取的知识图谱补全方法。【方法】通过视图编码器生成多个单视图网络,利用注意力机制融合不同视图信息作为实体的最终知识表示;通过不同的特征提取器分别提取头实体与关系的语义和交互特征,利用交叉注意力模块融合语义和交互特征并与尾实体进行匹配。【结果】在链接预测任务中的实验结果表明,与基线模型相比,本文模型在通用数据集FB15K-237和WN18RR上的Hits@10指标分别提升0.4和0.7个百分点,在领域数据集Kinship和UMLS上的Hits@10指标分别达到99.0%和99.9%。【局限】在视图更新时未更新关系,关系知识表示向量质量一般。【结论】多视图融合模型能够有效提升知识图谱表示质量,多特征提取框架能够有效提升链接预测精度。

关键词：知识图谱补全多视图注意力机制交互特征语义特征

A novel approach to the attitude stabilization structure for ducted-fan operative aerial robots:Finding improvements for modeling error and strong external transient disturbance

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Chinese Journal of Aeronautics 2022年第2期35卷 250-264页

作者： Wei FAN Bin XU Changle XIANG Yibo ZHANG haiyang yang School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401135China School of Automation Beijing Institute of TechnologyBeijing 100081China

This research concerns a novel attitude stabilization structure for a ducted-fan aerial robot to work against modeling error and strong external transient disturbance,and it focuses on two main control targets:modeling error compensation,and the improvement of disturbance resistance along the rolling *** the first research objective,we proposed an adaptive nominal controller with the reconfigurable control law design based on the estimation of the modeling error found in the *** of simulations and corresponding flight tests verified that the proposed adaptive control structure is robust against both constant and time-varying modeling *** the other research objective,a SAC(Stability Augmentation Control)structure was devised based on the CMG(Control Moment Gyroscope)theory in order to provide extra moment which effectively withstands the transient disturbance beyond the CDG(Critical Disturbance Gain).Furthermore,we studied the corresponding controller for the SAC via the SMC(sliding mode control)theory,while the working mechanism and performance of the SAC were verified through a specially devised prototype.

关键词： Adaptive control Disturbance rejection Ducted-fan aircraft Modeling error Stability augmentation systems

Influence of Oxygen-Containing Functional Groups on Asphaltene Self-Diffusion Coefficient in Asphaltene-Xylene Systems

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China Petroleum Processing & Petrochemical Technology 2022年第2期24卷 118-125页

作者： yang haiyang Wang Chunlu Ren Qiang Wang Lixin Yan Xuemin College of Chemistry&Environmental Engineering Yangtze UniversityJingzhou 434023 SINOPEC Research Institute of Petroleum Processing Beijing 100083

Molecular simulations were carried out to investigate the self-diffusion coefficient of asphaltene in asphaltene-xylene systems,used as heavy oil *** self-diffusion behavior of asphaltene in the asphaltene-xylene equilibrium system was mainly affected by the interaction between asphaltene molecules,with stronger interactions corresponding to a slower diffusion of *** interactions between asphaltene molecules mainly includedπ-πinteractions between aromatic rings and hydrogen bonds between strongly electronegative *** results are expected to provide theoretical guidance for reducing the viscosity of heavy oil.

关键词： heavy oil asphaltenes viscous mechanism molecular simulation molecular dynamics

Co-application of energy uncoupling and ultrafiltration in sludge treatment:Evaluations of sludge reduction,supernatant recovery and membrane fouling control

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Frontiers of Environmental Science & Engineering 2020年第4期14卷 43-52页

作者： An Ding Yingxue Zhao Zhongsen Yan Langming Bai haiyang yang Heng Liang Guibai Li Nanqi Ren State Key Laboratory of Urban Water Resource and Environment(SKLUWRE) Harbin Institute of TechnologyHarbin 150090China College of Civil Engineering Fuzhou UniversityFuzhou 350116China

Energy uncoupling is often used for sludge reduction because it is easy to operate and does not require a significant amount of extra equipments(*** additional tank required).However,over time the supernatant extracted using this method can deteriorate,ultimately requiring further *** purpose of this study was to determine the effect of using a low-pressure ultrafiltration membrane process for sludge water recovery after the sludge had undergone an energy uncoupling treatment(using 3,3’,4’,5-tetrachlorosalicylanilide(TCS)).Energy uncoupling was found to break apart sludge floe by reducing extracellular polymeric substances(EPS)and adenosine triphosphate(ATP)*** of supernatant indicated that when energy uncoupling and membrane filtration were coapplied and the TCS dosage was below 30 mg/L,there was no significant deterioration in organic component ***,ammonia and phosphate concentrations were found to increase as the concentration of TCS added ***,due to low sludge concentrations and EPS contents,addition of 30-60 mg/L TCS during sludge reduction increased the permeate flux(two times higher than the control)and decreased the hydraulic reversible and cake layer *** contrast,high dosage of TCS aggravated membrane fouling by forming compact fouling *** general,this study found that the co-application of energy uncoupling and membrane filtration processes represents an effective alternative method for simultaneous sludge reduction and sludge supernatant recovery.

关键词： Sludge reduction Energy uncoupling Ultrafiltration membrane Membrane fouling

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高韧性环氧树脂的制备及在复合材料中的应用

工程塑料应用 2025年第1期53卷 44-49页

作者：甘顺昌曾亮蒋庆庚刘文浩杨海洋黄安民彭超义株洲时代新材料科技股份有限公司湖南株洲412007

为探究不同纳米核壳增韧粒子对环氧树脂及其复合材料性能的影响,选用了3种纳米核壳增韧剂与自制的改性酸酐固化剂结合,制备出具有高韧性的环氧灌注树脂组合料。在固化前,对比测试了所制环氧树脂组合料的外观、密度、黏度和环氧值,发现... 详细信息

为探究不同纳米核壳增韧粒子对环氧树脂及其复合材料性能的影响,选用了3种纳米核壳增韧剂与自制的改性酸酐固化剂结合,制备出具有高韧性的环氧灌注树脂组合料。在固化前,对比测试了所制环氧树脂组合料的外观、密度、黏度和环氧值,发现黏度受增韧剂的影响尤为显著。利用差示扫描量热分析仪和万能材料试验机测试了环氧树脂固化物在不同温度下的力学性能和热性能。通过扫描电子显微镜(SEM)分析了树脂增韧的机理。采用真空灌注工艺,将环氧树脂制备成高韧性环氧树脂/玻璃布复合材料,并测试了复合材料在不同温度条件下的性能。结果显示,使用纳米核壳增韧剂的改性树脂的玻璃化转变温度超过140℃,显示出良好的耐热性。特别是采用增韧剂MX125的树脂,在-50℃的低温下,拉伸强度达到96.2MPa,冲击强度为36kJ/m^(2)。对比测试不同纳米粒子含量的改性树脂,发现当纳米粒子质量分数约为15%时,改性树脂的冲击韧性达到最佳。SEM观察树脂断面的微观结构表明,当树脂受到冲击发生断裂时,纳米粒子会在树脂断面的表面形成空穴或残留颗粒,有助于提高树脂的韧性。

关键词：环氧树脂纳米核壳增韧剂合成树脂复合材料改性

Synthesis of Hierarchical Porous Fe_(2)O_(3)/Al_(2)O_(3) Materials and Study on Catalytic Viscosity Reduction of Heavy Oil

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China Petroleum Processing & Petrochemical Technology 2022年第4期24卷 98-107页

作者： Wu Peiyue Ma Zhaofei yang haiyang Xiong Pan Tan Dichen Yan Xuemin College of Chemistry and Environmental Engineering Yangtze UniversityJingzhouHubei 434023PR China

Fe_(2)O_(3) nanoparticles were first dispersed in a sol solution containing an aluminum component introduced by an initial doping *** catalyst Hierarchical Porous Fe_(2)O_(3)/Al_(2)O_(3) materials(HPFA)were then synthesized through a sol-gel method via phase *** performance of HPFA was compared with that of Fe_(2)O_(3) nanoparticle *** structure of the composite catalyst was characterized by scanning electron microscopy,X-ray diffraction,N_(2) adsorption/desorption,and crush strength *** results showed that the Fe_(2)O_(3) nanoparticles could be loaded into the porous skeletons of Hierarchical Porous Al_(2)O_(3) materials(HPA)to achieve a uniform dispersion while avoiding agglomeration,which improved the mechanical strength of the porous materials *** HPFA was then used as a catalyst in the hydrothermal viscosity reduction process of Tuha heavy oil,and the viscosity reduction was *** viscosity reduction rate of HPFA was 81%,which was better than that of the Fe_(2)O_(3) nanoparticles(56%)and HPA(47%).

关键词： Fe_(2)O_(3) initial doping method hierarchical porous heavy oil viscosity reduction

Evaluation of Molecular Structural Effects on Needle Coke Mesophase Stacking

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China Petroleum Processing & Petrochemical Technology 2020年第3期22卷 94-100页

作者： yang haiyang Wang Chunlu Zhou Han Wang Lixin Ren Qiang Fan Qiming SINOPEC Research Institute of Petroleum Processing Beijing 100083

Molecular simulations were performed to investigate the molecular structural effects on needle coke mesophase *** simulation results showed that the stacking states of anthracene trimer and tetramer accumulations were orderly,while the stacking states of anthracene dimer,pentamer,and hexamer accumulations were *** trimer and tetramer in the model compounds were two of the most ideal needle coke mesophase *** was also found that the introduction of methyl side chains in anthracene trimer derivatives was not conducive to the formation of a mesophase *** sum up,the molecules which had similar structures to anthracene trimer or tetramer with no alkyl chains are ideal constituents of needle coke mesophase.

关键词： molecular simulation needle coke mesophase stacking interlayer spacing

Sign-reversed anomalous Nernst effect in the ferromagnetic Weyl-semimetal Fe_(3-δ)GeTe_(2): the role of Fe vacancies

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Science China(Physics,Mechanics & Astronomy) 2022年第11期65卷 125-131页

作者： haiyang yang Qi Wang Junwu Huang Zhouliang Wang Keqi Xia Chao Cao Mingliang Tian Zhuan Xu Jianhui Dai Yuke Li School of Physics and Hangzhou Key Laboratory of Quantum Matters Hangzhou Normal UniversityHangzhou 311121China Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field LaboratoryChineseAcademyof SciencesHefei 230031China Departmentof Physics Zhejiang UniversityHangzhou 310058China Zhejiang Province Key Laboratory of Quantum Technology and Device Zhejiang UniversityHangzhou 310027China

Anomalous Nernst effect, as a thermal partner of anomalous Hall effect, is particularly sensitive to the Berry curvature anomaly near the Fermi level, and has been used to probe the topological nature of quantum materials. In this work, we report the observation of both effects in the ferromagnetic Weyl-semimetal Fe_(3-δ)GeTe_(2) with tunable Fe vacancies. With decreasing Fe vacancies,the anomalous Hall conductivity evolves as a function of the longitudinal conductivity from the hopping region to the region where the intrinsic Berry curvature contribution dominates. Concomitant evolutions in the anomalous Nernst signal and the anomalous off-diagonal thermoelectric coefficient are observed below the Curie temperature, displaying a unique sign change caused by the Fe vacancies. Combining these results with first-principles calculations, we argue that the Fe-vacancy concentration plays a unique role in simultaneously tuning the chemical potential and ferromagnetism, which in turn controls the Berry curvature contribution in this family of ferromagnetic topological semimetals.

关键词： thermoelectronic effect Hall effect quantum transport topological Weyl semimetal