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Class-Imbalanced Machinery Fault Diagnosis using Heterogeneous Data Fusion Support Tensor Machine
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作者 Zhishan Min Minghui Shao +1 位作者 Haidong Shao Bin Liu 《Journal of Dynamics, Monitoring and Diagnostics》 2025年第1期11-21,共11页
The monitoring signals of bearings from single-source sensor often contain limited information for characterizing various working condition,which may lead to instability and uncertainty of the class-imbalanced intelli... The monitoring signals of bearings from single-source sensor often contain limited information for characterizing various working condition,which may lead to instability and uncertainty of the class-imbalanced intelligent fault diagnosis.On the other hand,the vectorization of multi-source sensor signals may not only generate high-dimensional vectors,leading to increasing computational complexity and overfitting problems,but also lose the structural information and the coupling information.This paper proposes a new method for class-imbalanced fault diagnosis of bearing using support tensor machine(STM)driven by heterogeneous data fusion.The collected sound and vibration signals of bearings are successively decomposed into multiple frequency band components to extract various time-domain and frequency-domain statistical parameters.A third-order hetero-geneous feature tensor is designed based on multisensors,frequency band components,and statistical parameters.STM-based intelligent model is constructed to preserve the structural information of the third-order heterogeneous feature tensor for bearing fault diagnosis.A series of comparative experiments verify the advantages of the proposed method. 展开更多
关键词 class-imbalanced fault diagnosis feature tensor heterogeneous data fusion support tensor machine
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Recent advances on additive manufacturing of heterogeneous/gradient metallic materials via laser powder bed fusion
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作者 Di Wang Linqing Liu +10 位作者 Jinrong Tang Yang Liu Chao Wei Zhixiao Weng Jiawei Shao Hua Tan Wei Zhou Bram Neirinck Nicolas Gianfolcaro Yongqiang Yang Changjun Han 《International Journal of Extreme Manufacturing》 2025年第6期247-295,共49页
Multi-material laser powder bed fusion(LPBF)additive manufacturing is a promising approach for integrating the functionality and mechanical performance of dissimilar materials into complex parts.This review offers a c... Multi-material laser powder bed fusion(LPBF)additive manufacturing is a promising approach for integrating the functionality and mechanical performance of dissimilar materials into complex parts.This review offers a comprehensive overview of the recent advancements in multi-material LPBF,with a particular focus on compositionally heterogeneous/gradient parts and their fabrication methods and equipment,control of interfacial defects,innovative designs,and potential applications.It commences with the introduction of LPBF-processed compositionally heterogeneous/gradient structures with dissimilar material distributions,including Z-direction compositionally heterogeneous structures,compositionally gradient structures in the Z-direction and XY planes,and three-dimensional(3D)compositionally heterogeneous structures.Subsequently,various LPBF methods and equipment for fabricating compositionally heterogeneous/gradient structures have been presented.Furthermore,the interfacial defects and process control during LPBF for these types of compositionally heterogeneous/gradient structures are discussed.Additionally,innovative designs and potential applications of parts made from compositionally heterogeneous/gradient structures are illustrated.Finally,perspectives on the LPBF fabrication methods for compositionally heterogeneous/gradient structures are highlighted to provide guidance for future research. 展开更多
关键词 laser powder bed fusion compositionally heterogeneous structures compositionally gradient structures interfacial defects potential applications
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Multi-Source Heterogeneous Data Fusion Analysis Platform for Thermal Power Plants
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作者 Jianqiu Wang Jianting Wen +1 位作者 Hui Gao Chenchen Kang 《Journal of Architectural Research and Development》 2025年第6期24-28,共5页
With the acceleration of intelligent transformation of energy system,the monitoring of equipment operation status and optimization of production process in thermal power plants face the challenge of multi-source heter... With the acceleration of intelligent transformation of energy system,the monitoring of equipment operation status and optimization of production process in thermal power plants face the challenge of multi-source heterogeneous data integration.In view of the heterogeneous characteristics of physical sensor data,including temperature,vibration and pressure that generated by boilers,steam turbines and other key equipment and real-time working condition data of SCADA system,this paper proposes a multi-source heterogeneous data fusion and analysis platform for thermal power plants based on edge computing and deep learning.By constructing a multi-level fusion architecture,the platform adopts dynamic weight allocation strategy and 5D digital twin model to realize the collaborative analysis of physical sensor data,simulation calculation results and expert knowledge.The data fusion module combines Kalman filter,wavelet transform and Bayesian estimation method to solve the problem of data time series alignment and dimension difference.Simulation results show that the data fusion accuracy can be improved to more than 98%,and the calculation delay can be controlled within 500 ms.The data analysis module integrates Dymola simulation model and AERMOD pollutant diffusion model,supports the cascade analysis of boiler combustion efficiency prediction and flue gas emission monitoring,system response time is less than 2 seconds,and data consistency verification accuracy reaches 99.5%. 展开更多
关键词 Thermal power plant Multi-source heterogeneous data Data fusion analysis platform Edge computing
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Achieving ultrafine,fully equiaxed grains and heterogeneous structures in laser powder bed fusion 316L stainless steel through in-situ alloying
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作者 Shuqi Gong Shuai Guo +10 位作者 Long Liu Moyu Zhang Longda Wang Yaotang Ji Junjie Ni Wenlu Yang Anfu Guo Shushuai Liu Shang Sui Meng Wang Xin Lin 《Additive Manufacturing Frontiers》 2025年第4期148-162,共15页
Although 316L stainless steel(SS316L)exhibits favorable ductility and toughness,its limited strength restricts its applicability.This study addressed this limitation by preparing a series of SS316L-xTC4 alloys(where x... Although 316L stainless steel(SS316L)exhibits favorable ductility and toughness,its limited strength restricts its applicability.This study addressed this limitation by preparing a series of SS316L-xTC4 alloys(where x indicates Ti6Al4V(TC4)contents of 0.5 wt%,1 wt%,2 wt%,and 4 wt%)with equiaxed grains,ultrafine grains,and heterogeneous structures using in-situ alloying via laser powder bed fusion.The Ti,Al,and V in the TC4 alloy were shown to stabilize and promote the formation of theαphase,which is stronger than theγphase in typical SS316L.Furthermore,these solute elements readily formed nanoparticles with impurities,such as C and O,to increase the nucleation rate and thereby achieve grain refinement.This resulted in the formation of ultrafine grains predominantly within theαphase,where the solute elements were primarily distributed.The formation of theαphase also impeded the growth of theγphase;coupled with the effects of the nanoparticles,this also significantly reduced the grain size in theγphase.Notably,the SS316L-2TC4 alloy exhibited fully equiaxed grains,and the coexistence of theαandγphases as well as ultrafine and coarse grains formed heterogeneous grain and dual-phase structures within.The synergistic effects of equiaxed grains,ultrafine grains,and heterostructures produced an SS316L alloy that exhibited both excellent strength and elongation. 展开更多
关键词 316L stainless steel Laser powder bed fusion Equiaxed grain Ultrafine grain heterogeneous structure
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Laser powder bed fusion of Mg-6Gd-3Y-0.2Zr alloy:Excellent printability,heterogeneous microstructure and dedicated direct aging heat treatment
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作者 Qingchen Deng Jing Luo +9 位作者 Ziyi Liu Qianye Wu Dazhi Liu Lianmei Wu Fei Li Manman Yi Penghuai Fu Yujuan Wu Liming Peng Wenjiang Ding 《Journal of Magnesium and Alloys》 2025年第10期4891-4911,共21页
As a universal casting Mg-RE alloy,Mg-6Gd-3Y-Zr(GW63K,wt.%)alloy exhibits superior strength-ductility synergy and holds significant potential for engineering applications.In this study,the GW63K alloy is produced usin... As a universal casting Mg-RE alloy,Mg-6Gd-3Y-Zr(GW63K,wt.%)alloy exhibits superior strength-ductility synergy and holds significant potential for engineering applications.In this study,the GW63K alloy is produced using the laser powder bed fusion(LPBF)additive manufacturing(AM)process for the first time.The printability,microstructure characteristics,and post-heat treatment conditions of the GW63K alloy are systematically investigated.The as-built GW63K samples demonstrate high relative densities exceeding 99.6%and exhibit no macroscopic and microscopic cracking across a wide range of process parameters,indicating excellent printability.An exceptional heterogeneous microstructure is observed in the as-built GW63K alloy,comprising coarse columnar grains,fine equiaxed grains with an average grain size of 21.72μm,uniformly distributed nano-sized Mg_(24)(Gd,Y)_(5)secondary phase,and numerous dislocations.Consequently,the as-built GW63K alloy displays enhanced tensile strengths and ductility compared to the as-cast alloy,with yield strength(YS),ultimate tensile strength(UTS)and elongation(EL)values of 218±4 MPa,284±5 MPa and 11.9±1.6%respectively.Additionally,due to the absence of coarse micron-sized secondary phase,a specific direct aging(T5)heat treatment regime at 200℃for 128 h is optimized for the as-built GW63K alloy to introduce dense and dispersedβ’aging precipitates.This T5 treatment surpasses the conventional solution plus aging(T6)heat treatment in enhancing mechanical properties.The LPBF-T5 GW63K alloy exhibits YS,UTS and EL values of 293±6 MPa,359±4 MPa and 2.9±0.7%,respectively.Notably,the YS of the LPBF-T5 alloy represents the highest value for the GW63K alloy,even surpassing that of the extrusion-T5 alloy.This study indicates that the GW63K alloy is a highly promising material for manufacturing near-net-shape high-strength Mg alloy components with intricate geometries using LPBF. 展开更多
关键词 Laser powder bed fusion(LPBF) Mg-Gd-Y-Zr alloy PRINTABILITY heterogeneous microstructure Direct aging heat treatment
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Interfacial Heterogeneous Microstructure and Subsequent Machinability of 316L/CuSn10 Bimetallic Structure Manufactured by Laser Powder Bed Fusion 被引量:1
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作者 Jie Chen Zhongpeng Zheng +2 位作者 Di Wang Guijun Bi Yuchao Bai 《Additive Manufacturing Frontiers》 2024年第3期100-112,共13页
Additively manufactured bimetallic structures combine the advantages of dissimilar materials and can achieve localized properties through a customized composition distribution.However,additively manufactured parts may... Additively manufactured bimetallic structures combine the advantages of dissimilar materials and can achieve localized properties through a customized composition distribution.However,additively manufactured parts may still lack the dimensional accuracy and surface integrity essential for precision mechanical assemblies that the post-machining process can address.Therefore,this study aims to systematically investigate the microstructure and machinability of 316L/CuSn10 bimetallic structures fabricated using laser powder bed fusion.The results show that the fusion zone of the bimetallic structure had refined grains of microscale size owing to the mixture of the primary elements of the bimetals,which resulted in the highest microhardness of 3.4 GPa.The difference in microstructure and microhardness between the single-material and fusion zones also causes significant differences in the cutting response during the ultraprecision process.The 316L stainless steel side exhibited the highest cutting force and more severe material accumulation in the chips.The cutting force drops when cutting through the fusion zone,with an observable fracture in the chips and separation of dissimilar materials on the machined grooves,indicating that the heterogeneous properties of additively manufactured 316L/CuSn10 bimetallic structures pose challenges to the improvement of surface quality.The simulation results also showed that stress accumulation occurred in the tool path through the fusion zone owing to the higher yield strength and hardness of stainless steel,indicating that lower cutting speeds and depths of cut are favorable for reducing cutting force and improving surface quality.This study provides deep insight into the microstructure evolution mechanism and a theoretical basis for improving the surface quality of additively manufactured bimetallic structures using an ultraprecision machining process. 展开更多
关键词 Laser powder bed fusion Bimetallic structure heterogeneous microstructures Ultra-precision machining MACHINABILITY
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A Heterogeneous Information Fusion Method for Maritime Radar and AIS Based on D-S Evidence Theory
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作者 Chao Wu Qing Wu +1 位作者 Feng Ma Shuwu Wang 《Engineering(科研)》 2023年第12期821-842,共22页
Maritime radar and automatic identification systems (AIS), which are essential auxiliary equipment for navigation safety in the shipping industry, have played significant roles in maritime safety supervision. However,... Maritime radar and automatic identification systems (AIS), which are essential auxiliary equipment for navigation safety in the shipping industry, have played significant roles in maritime safety supervision. However, in practical applications, the information obtained by a single device is limited, and it is necessary to integrate the information of maritime radar and AIS messages to achieve better recognition effects. In this study, the D-S evidence theory is used to fusion the two kinds of heterogeneous information: maritime radar images and AIS messages. Firstly, the radar image and AIS message are processed to get the targets of interest in the same coordinate system. Then, the coordinate position and heading of targets are chosen as the indicators for judging target similarity. Finally, a piece of D-S evidence theory based on the information fusion method is proposed to match the radar target and the AIS target of the same ship. Particularly, the effectiveness of the proposed method has been validated and evaluated through several experiments, which proves that such a method is practical in maritime safety supervision. 展开更多
关键词 D-S Evidence Theory heterogeneous Information fusion Radar Image AIS Message
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Role of heterogenous microstructure and deformation behavior in achieving superior strength-ductility synergy in zinc fabricated via laser powder bed fusion 被引量:5
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作者 Zhi Dong Changjun Han +7 位作者 Yanzhe Zhao Jinmiao Huang Chenrong Ling Gaoling Hu Yunhui Wang Di Wang Changhui Song Yongqiang Yang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第4期225-245,共21页
Zinc(Zn)is considered a promising biodegradable metal for implant applications due to its appropriate degradability and favorable osteogenesis properties.In this work,laser powder bed fusion(LPBF)additive manufacturin... Zinc(Zn)is considered a promising biodegradable metal for implant applications due to its appropriate degradability and favorable osteogenesis properties.In this work,laser powder bed fusion(LPBF)additive manufacturing was employed to fabricate pure Zn with a heterogeneous microstructure and exceptional strength-ductility synergy.An optimized processing window of LPBF was established for printing Zn samples with relative densities greater than 99%using a laser power range of 80∼90 W and a scanning speed of 900 mm s−1.The Zn sample printed with a power of 80 W at a speed of 900 mm s−1 exhibited a hierarchical heterogeneous microstructure consisting of millimeter-scale molten pool boundaries,micrometer-scale bimodal grains,and nanometer-scale pre-existing dislocations,due to rapid cooling rates and significant thermal gradients formed in the molten pools.The printed sample exhibited the highest ductility of∼12.1%among all reported LPBF-printed pure Zn to date with appreciable ultimate tensile strength(∼128.7 MPa).Such superior strength-ductility synergy can be attributed to the presence of multiple deformation mechanisms that are primarily governed by heterogeneous deformation-induced hardening resulting from the alternative arrangement of bimodal Zn grains with pre-existing dislocations.Additionally,continuous strain hardening was facilitated through the interactions between deformation twins,grains and dislocations as strain accumulated,further contributing to the superior strength-ductility synergy.These findings provide valuable insights into the deformation behavior and mechanisms underlying exceptional mechanical properties of LPBF-printed Zn and its alloys for implant applications. 展开更多
关键词 laser powder bed fusion ZINC heterogeneous microstructure bimodal grains strength-ductility synergy
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A Spatially Heterogeneous Expert Based (SHEB) Urban Growth Model using Model Regionalization 被引量:4
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作者 Dimitrios Triantakonstantis Giorgos Mountrakis Jida Wang 《Journal of Geographic Information System》 2011年第3期195-210,共16页
Urbanization changes have been widely examined and numerous urban growth models have been proposed. We introduce an alternative urban growth model specifically designed to incorporate spatial heterogeneity in urban gr... Urbanization changes have been widely examined and numerous urban growth models have been proposed. We introduce an alternative urban growth model specifically designed to incorporate spatial heterogeneity in urban growth models. Instead of applying a single method to the entire study area, we segment the study area into different regions and apply targeted algorithms in each subregion. The working hypothesis is that the integration of appropriately selected region-specific models will outperform a globally applied model as it will incorporate further spatial heterogeneity. We examine urban land use changes in Denver, Colorado. Two land use maps from different time snapshots (1977 and 1997) are used to detect the urban land use changes, and 23 explanatory factors are produced to model urbanization. The proposed Spatially Heterogeneous Expert Based (SHEB) model tested decision trees as the underlying modeling algorithm, applying them in different subregions. In this paper the segmentation tested is the division of the entire area into interior and exterior urban areas. Interior urban areas are those situated within dense urbanized structures, while exterior urban areas are outside of these structures. Obtained results on this model regionalization technique indicate that targeted local models produce improved results in terms of Kappa, accuracy percentage and multi-scale performance. The model superiority is also confirmed by model pairwise comparisons using t-tests. The segmentation criterion of interior/exterior selection may not only capture specific characteristics on spatial and morphological properties, but also socioeconomic factors which may implicitly be present in these spatial representations. The usage of interior and exterior subregions in the present study acts as a proof of concept. Other spatial heterogeneity indicators, for example landscape, socioeconomic and political boundaries could act as the basis for improved local segmentations. 展开更多
关键词 URBAN Growth Models Spatial heterogenEITY MODEL fusion DECISION Trees Denver
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Laser powder bed fusion of high-strength Sc/Zr-modified Al–Mg alloy:phase selection,microstructural/mechanical heterogeneity,and tensile deformation behavior 被引量:7
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作者 Zihong Wang Xin Lin +6 位作者 Nan Kang Jing Chen Hua Tan Zhe Feng Zehao Qin Haiou Yang Weidong Huang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第36期40-56,共17页
Laser powder bed fusion(L-PBF)of Sc/Zr-modified Al-based alloys has recently become a promising method for developing a new generation of high-performance Al alloys.To clarify the modification roles of Sc/Zr elements,... Laser powder bed fusion(L-PBF)of Sc/Zr-modified Al-based alloys has recently become a promising method for developing a new generation of high-performance Al alloys.To clarify the modification roles of Sc/Zr elements,an Al–4.66Mg–0.48Mn–0.72Sc–0.33Zr(wt.%)alloy was processed using L-PBF.The effect of the local solidification condition of the molten pool on the precipitation behavior of primary Al_(3)(Sc,Zr)was analyzed based on time-dependent nucleation theory.It was found that primary Al_(3)(Sc,Zr)inevitably precipitated at the fusion boundary,while its precipitation could be effectively suppressed in the inner region of the molten pool.This subsequently induced the formation of a heterogeneousα-Al matrix.After direct aging,the heredity of solidification microstructure introduced heterogeneous secondary Al_(3)(Sc,Zr)precipitates withinα-Al matrix.Owing to the inverse relationship between grain boundary strengthening and precipitation strengthening,the direct-aged sample with dual heterogeneous structures exhibited reduced mechanical heterogeneity,resulting in lowered hetero-deformation-induced hardening.The low strain-hardening capability in the direct-aged sample promoted necking instability while inducing a large Lüders elongation,which effectively improved the tensile ductility. 展开更多
关键词 Additive manufacturing Al–Mg–Sc–Zr alloys Laser powder bed fusion heterogeneous microstructure Deformation behavior
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Distributed state estimation for heterogeneous mobile sensor networks with stochastic observation loss 被引量:1
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作者 Yingrong YU Jianglong YU +1 位作者 Yishi LIU Zhang REN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第2期265-275,共11页
The problem of distributed fusion and random observation loss for mobile sensor networks is investigated herein.In view of the fact that the measured values,sampling frequency and noise of various sensors are differen... The problem of distributed fusion and random observation loss for mobile sensor networks is investigated herein.In view of the fact that the measured values,sampling frequency and noise of various sensors are different,the observation model of a heterogeneous network is constructed.A binary random variable is introduced to describe the drop of observation component and the topology switching problem caused by complete observation loss is also considered.A cubature information filtering algorithm is adopted to design local filters for each observer to suppress the negative effects of measurement noise.To derive a consistent and accurate estimation result,a novel weighted average consensus-based filtering approach is put forward.For the sensor that suffers from observation loss,its local prediction information vector is fused with the information contribution vectors of the neighbors to obtain the local estimation.Then the consensus weight matrix is designed for consensus-based distributed collaborative information fusion.The boundness of the estimation errors is proved by employing the stochastic stability theory.In the end,two numerical examples are offered to assert the validity of the presented method. 展开更多
关键词 Consistency theorem heterogeneous sensor networks Information fusion State estimation Stochastic boundedness
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Dynamic Modeling of Heterogeneous Spatial Analysis for Energy and Natural Resources in Grid Integration Environment
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作者 Wei Ji,Xincai Wu Faculty of Information Engineering,China University of Geosciences(Wuhan),Wuhan 430074,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期287-287,共1页
With the high-tech industrialization of earth observation satellite remote sensing and the implementation of digital earth strategy,the energy and natural resources have been decided to be the key research fields in C... With the high-tech industrialization of earth observation satellite remote sensing and the implementation of digital earth strategy,the energy and natural resources have been decided to be the key research fields in China.In these fields,from the model based on topology data,through simple feature data model to rule-based data model,the basic spatial analysis algorithms have been developed 展开更多
关键词 DYNAMIC modeling of heterogeneous spatial analysis suspended inversion architecture FUNCTION WAREHOUSE FUNCTION POLYMERIZATION FUNCTION fusion operator OVERLOADING
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Evaluating Urban Housing Contradictions Through Multisource Data Fusion:a Case Study of Spatiotemporal Mismatch Analysis in Shenzhen with the HCEWI Model
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作者 JIANG Aiyi CHEN Guanzhou CAO Jinzhou 《Journal of Geodesy and Geoinformation Science》 2025年第3期1-16,共16页
The rapid urbanization and structural imbalances in Chinese megacities have exacerbated the housing supplydemand mismatch,creating an urgent need for fine-scale diagnostic tools.This study addresses this critical gap ... The rapid urbanization and structural imbalances in Chinese megacities have exacerbated the housing supplydemand mismatch,creating an urgent need for fine-scale diagnostic tools.This study addresses this critical gap by developing the Housing Contradiction Evaluation Weighted Index(HCEWI)model,making three key contributions to high-resolution housing monitoring.First,we establish a tripartite theoretical framework integrating dynamic population pressure(PPI),housing supply potential(HSI),and functional diversity(HHI).The PPI innovatively combines mobile signaling data with principal component analysis to capture real-time commuting patterns,while the HSI introduces a novel dual-criteria system based on Local Climate Zones(LCZ),weighted by building density and residential function ratio.Second,we develop a spatiotemporal coupling architecture featuring an entropy-weighted dynamic integration mechanism with self-correcting modules,demonstrating robust performance against data noise.Third,our 25-month longitudinal analysis in Shenzhen reveals significant findings,including persistent bipolar clustering patterns,contrasting volatility between peripheral and core areas,and seasonal policy responsiveness.Methodologically,we advance urban diagnostics through 500-meter grid monthly monitoring and process-oriented temporal operators that reveal“tentacle-like”spatial restructuring along transit corridors.Our findings provide a replicable framework for precision housing governance and demonstrate the transformative potential of mobile signaling data in implementing China’s“city-specific policy”approach.We further propose targeted intervention strategies,including balance regulation for high-contradiction zones,Transit-Oriented Development(TOD)activation for low-contradiction clusters,and dynamic land conversion mechanisms for transitional areas. 展开更多
关键词 index terms-housing contradiction assessment multi-source data fusion spatiotemporal heterogeneity job-housing spatial mismatch high-resolution urban diagnostics
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基于文本引导的轻量异构编码多模态图像融合
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作者 王传云 周明奇 +3 位作者 孙冬冬 王田 高骞 李照奎 《工程科学学报》 北大核心 2026年第2期346-359,共14页
针对资源受限的无人机平台对红外与可见光图像的融合效率与感知性能需求,本文提出一种基于文本引导的轻量异构编码多模态图像融合网络.该网络设计了一种面向红外与可见光图像信息表达功能互补的轻量化双分支异构编码,红外图像编码分支... 针对资源受限的无人机平台对红外与可见光图像的融合效率与感知性能需求,本文提出一种基于文本引导的轻量异构编码多模态图像融合网络.该网络设计了一种面向红外与可见光图像信息表达功能互补的轻量化双分支异构编码,红外图像编码分支强调热目标与边缘响应,可见光图像编码分支侧重于纹理与细节信息建模,从而有效避免同构编码器带来的特征冗余与性能瓶颈.同时,引入轻量级跨模态特征融合模块,增强多模信息之间的互补性与融合表达能力.进一步,通过预训练视觉语言模型结合语义文本特征对融合过程进行引导与调控,提升融合图像的语义一致性与环境适应性.在三个公开多模态图像数据集TNO、LLVIP与M3FD上,本文方法与九种代表性图像融合算法进行了系统对比实验与综合评估,结果显示本文网络在互信息、结构相似性等多个主流评价指标上均表现优越,融合图像在细节清晰度、边缘结构一致性与目标可辨性方面优于现有方法.同时,消融实验表明所提出模型的推理时间相较基线方法减少约50%,且在不显著牺牲性能的前提下实现了更高的效率.除定量评估外,本文还开展了基于文本指令的定性实验,结果显示模型可根据不同语义指令灵活调整红外与可见光特征融合策略,适应低光、过曝、低对比、噪声等多种任务场景.在保证语义一致性的同时,有效增强了热源感知、结构清晰度与抗干扰能力,展现出传统无引导方法难以实现的语义可控性与内容适应性. 展开更多
关键词 多模态图像融合 双分支异构编码 文本引导 轻量化网络 注意力机制
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融合多关系异构图和语义特征的核心专利预测方法
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作者 邓娜 纪媛琳 胡云川 《情报杂志》 北大核心 2026年第1期83-90,共8页
[目的]随着专利数量的爆发式增长,专利间关系日益复杂,现有核心专利预测方法仅依赖单一专利关系网络,难以有效捕捉专利间的多维关联,且未能综合专利的文本信息。因此,实现一种能融合多维度特征的核心专利预测方法具有重要意义。[方法]... [目的]随着专利数量的爆发式增长,专利间关系日益复杂,现有核心专利预测方法仅依赖单一专利关系网络,难以有效捕捉专利间的多维关联,且未能综合专利的文本信息。因此,实现一种能融合多维度特征的核心专利预测方法具有重要意义。[方法]提出一种融合多关系异构图与语义特征的核心专利预测方法。通过构建多关系异构图整合专利间技术共现、共享发明人以及权利要求语义相似多维度关系,并融合XLnet提取的专利摘要语义特征,最终利用MLP分类器实现核心专利预测。[结果/结论]实验结果表明,在通信产业领域的专利数据集上,方法的Precision、Recall、Macro F1以及AUC分数分别达到0.8562、0.8210、0.8059、0.8260,超越了其他4个对比方法,证明了方法的有效性,能为核心专利预测提供新的参考和思路。 展开更多
关键词 核心专利预测 多关系异构图 特征融合 RGCN XLnet
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Achieving high strength in laser powder-bed fusion processed AlFeCuZr alloy via dual-nanoprecipitations and grain boundary segregation 被引量:2
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作者 Jing-Yu Xu Cheng Zhang +3 位作者 Li-Xue Liu Rong Guo Ming-Jun Sun Lin Liu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第6期56-66,共11页
Additive manufacturing of aluminum alloys has received significant attention in the aerospace industry;however,achieving sufficient high strength,especially at elevated temperatures,remains challenging.Here,a crack-fr... Additive manufacturing of aluminum alloys has received significant attention in the aerospace industry;however,achieving sufficient high strength,especially at elevated temperatures,remains challenging.Here,a crack-free and near-full dense Al-1Fe-0.6Cu-1.3Zr alloy was fabricated by the laser powder bed fusion(LPBF)technique.The Al-Fe-Cu-Zr alloy exhibits heterogeneous microstructures with two distinct zones.One is the so-called coarse-grain zones(CGZs)with an average grain size of 0.95μm,where(Al,Cu)Fe_(3) nanoparticles precipitate in the Al matrix and Fe and Cu cosegregate at the grain boundaries(GBs).The other is fine-grain zones(FGZs)with an average grain size of 0.45μm,where an Al 3 Zr nanoparti-cle precipitates in each of theα-Al grains(serves as the nuclei),and Fe-rich nanoprecipitates and Fe/Cu cosegregation appear at the GBs.As a result,the LPBF Al-Fe-Cu-Zr alloy,with these unique heteroge-neous structures,displays high strength at both room temperature and elevated temperatures,e.g.,with high yield strengths of 500 MPa at room temperature,and 163 MPa at 573 K,both are higher than those of additive manufactured Al-based alloys reported thus far.It is suggested that the high strength over a wide temperature range of the current LPBF Al alloy is mainly attributed to the combination of the precipitation strengthening mechanism and grain-boundary strengthening mechanism. 展开更多
关键词 Laser powder bed fusion Aluminum alloy heterogeneous microstructure NANOPRECIPITATION High strength
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Microstructure evolution and strengthening mechanisms of a high-performance TiN-reinforced Al-Mn-Mg-Sc-Zr alloy processed by laser powder bed fusion 被引量:2
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作者 Hao Tang Xiaoying Xi +5 位作者 Chaofeng Gao Zhongqiang Liu Jiantao Zhang Weiwen Zhang Zhiyu Xiao Jeremy Heng Rao 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第20期86-100,共15页
In this work,a high-strength crack-free TiN/Al-Mn-Mg-Sc-Zr composite was fabricated by laser powder bed fusion(L-PBF).A large amount of uniformly distributed L1_(2)-Al_(3)(Ti,Sc,Zr)nanoparticles were formed during the... In this work,a high-strength crack-free TiN/Al-Mn-Mg-Sc-Zr composite was fabricated by laser powder bed fusion(L-PBF).A large amount of uniformly distributed L1_(2)-Al_(3)(Ti,Sc,Zr)nanoparticles were formed during the L-PBF process due to the partial melting and decomposition of TiN nanoparticles under a high temperature.These L1_(2)-Al_(3)(Ti,Sc,Zr)nanoparticles exhibited a highly coherent lattice relationship with the Al matrix.All the prepared TiN/Al-Mn-Mg-Sc-Zr composite samples exhibit ultrafine grain mi-crostructure.In addition,the as-built composite containing 1.5 wt%TiN shows an excellent tensile prop-erty with a yield strength of over 580 MPa and an elongation of over 8%,which were much higher than those of wrought 7xxx alloys.The effects of various strengthening mechanisms were quantitatively estimated and the high strength of the alloy was mainly attributed to the refined microstructure,solid solution strengthening,and precipitation strengthening contributed by L1_(2)-Al_(3)(Ti,Sc,Zr)nanoparticles. 展开更多
关键词 Laser powder bed fusion Aluminum matrix composites heterogeneous nucleation Strengthening mechanisms Mechanical performance
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Synchrotron Characterisation of Ultra-Fine Grain TiB_(2)/Al-Cu Composite Fabricated by Laser Powder Bed Fusion 被引量:1
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作者 Sheng Li Biao Cai +5 位作者 Ranxi Duan Lei Tang Zihan Song Dominic White Oxana V.Magdysyuk Moataz M.Attallah 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2022年第1期78-92,共15页
Isotropy in microstructure and mechanical properties remains a challenge for laser powder bed fusion(LPBF)processed materials due to the epitaxial growth and rapid cooling in LPBF.In this study,a high-strength TiB_(2)... Isotropy in microstructure and mechanical properties remains a challenge for laser powder bed fusion(LPBF)processed materials due to the epitaxial growth and rapid cooling in LPBF.In this study,a high-strength TiB_(2)/Al-Cu composite with random texture was successfully fabricated by laser powder bed fusion(LPBF)using pre-doped TiB_(2)/Al-Cu composite powder.A series of advanced characterisation techniques,including synchrotron X-ray tomography,correlative focussed ion beam-scanning electron microscopy(FIB-SEM),scanning transmission electron microscopy(STEM),and synchrotron in situ X-ray diffraction,were applied to investigate the defects and microstructure of the as-fabricated TiB_(2)/Al-Cu composite across multiple length scales.The study showed ultra-fine grains with an average grain size of about 0.86μm,and a random texture was formed in the as-fabricated condition due to rapid solidification and the TiB_(2)particles promoting heterogeneous nucleation.The yield strength and total elongation of the as-fabricated composite were 317 MPa and 10%,respectively.The contributions of fine grains,solid solutions,dislocations,particles,and Guinier-Preston(GP)zones were calculated.Failure was found to be initiated from the largest lack-of-fusion pore,as revealed by in situ synchrotron tomography during tensile loading.In situ synchrotron diffraction was used to characterise the lattice strain evolution during tensile loading,providing important data for the development of crystal-plasticity models. 展开更多
关键词 Aluminium metal matrix composite Laser powder bed fusion heterogeneous nucleation Synchrotron characterisation
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Recrystallization effect on surface passivation of Hastelloy X alloy fabricated by laser powder bed fusion
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作者 Xing He Li Wang +6 位作者 Decheng Kong Ruixue Li Wei Zhang Kunjie Dai Xiaoqing Ni Ketai He Chaofang Dong 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第32期245-258,共14页
Post-heat treatment is generally adopted in the additive manufacturing field due to its alleviation of high residual stress and modification of rapid-solidified multilevel heterogeneous microstructure,and the related ... Post-heat treatment is generally adopted in the additive manufacturing field due to its alleviation of high residual stress and modification of rapid-solidified multilevel heterogeneous microstructure,and the related performance of the heat-treated counterparts calls for a systemic investigation to build a criterion of the heat treatment procedure.In this work,we focus on the heat treatment effects on the recrystallization of the Hastelloy X alloy produced by the laser powder bed fusion(LPBF)method,and the related surface passivation of the heat-treated counterparts is meticulously assessed as well.Results show that the multilevel heterostructure for LPBF Hastelloy X alloy consists of sub-micro dislocation cell substructures with Cr/Mo elemental segregation,fine columnar grains,and periodically-distributed molten pools.After heat treatment,partially and fully recrystallized structures for LPBF Hastelloy X alloys were achieved at 1100 and 1200℃for 1 h,respectively.Furthermore,the as-built LPBF Hastelloy X alloy shows superior corrosion resistance while the heat-treated one(1100℃)exhibits the worst in the borate buffer solution.The growth of passive film exhibited a highly linear correlation with the nucleation process controlled by diffusion,and high dislocation density and low angle grain boundary decreased the diffusion coefficient of cation vacancies,augmenting the nucleation sites of the passive film and enhancing its growth rate.Moreover,the micro-galvanic effect resulting from the partially recrystallized microstructure actively facilitated the formation of inhomogeneous porous passive films,leading to the worst corrosion resistance. 展开更多
关键词 Laser powder bed fusion Hastelloy X RECRYSTALLIZATION heterogeneous microstructure Passive film
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Hierarchical Optimization Method for Federated Learning with Feature Alignment and Decision Fusion
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作者 Ke Li Xiaofeng Wang Hu Wang 《Computers, Materials & Continua》 SCIE EI 2024年第10期1391-1407,共17页
In the realm of data privacy protection,federated learning aims to collaboratively train a global model.However,heterogeneous data between clients presents challenges,often resulting in slow convergence and inadequate... In the realm of data privacy protection,federated learning aims to collaboratively train a global model.However,heterogeneous data between clients presents challenges,often resulting in slow convergence and inadequate accuracy of the global model.Utilizing shared feature representations alongside customized classifiers for individual clients emerges as a promising personalized solution.Nonetheless,previous research has frequently neglected the integration of global knowledge into local representation learning and the synergy between global and local classifiers,thereby limiting model performance.To tackle these issues,this study proposes a hierarchical optimization method for federated learning with feature alignment and the fusion of classification decisions(FedFCD).FedFCD regularizes the relationship between global and local feature representations to achieve alignment and incorporates decision information from the global classifier,facilitating the late fusion of decision outputs from both global and local classifiers.Additionally,FedFCD employs a hierarchical optimization strategy to flexibly optimize model parameters.Through experiments on the Fashion-MNIST,CIFAR-10 and CIFAR-100 datasets,we demonstrate the effectiveness and superiority of FedFCD.For instance,on the CIFAR-100 dataset,FedFCD exhibited a significant improvement in average test accuracy by 6.83%compared to four outstanding personalized federated learning approaches.Furthermore,extended experiments confirm the robustness of FedFCD across various hyperparameter values. 展开更多
关键词 Federated learning data heterogeneity feature alignment decision fusion hierarchical optimization
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