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Enhanced Capacity Reversible Data Hiding Based on Pixel Value Ordering in Triple Stego Images
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作者 Kim Sao Nguyen Ngoc Dung Bui 《Computers, Materials & Continua》 2026年第1期1571-1586,共16页
Reversible data hiding(RDH)enables secret data embedding while preserving complete cover image recovery,making it crucial for applications requiring image integrity.The pixel value ordering(PVO)technique used in multi... Reversible data hiding(RDH)enables secret data embedding while preserving complete cover image recovery,making it crucial for applications requiring image integrity.The pixel value ordering(PVO)technique used in multi-stego images provides good image quality but often results in low embedding capability.To address these challenges,this paper proposes a high-capacity RDH scheme based on PVO that generates three stego images from a single cover image.The cover image is partitioned into non-overlapping blocks with pixels sorted in ascending order.Four secret bits are embedded into each block’s maximum pixel value,while three additional bits are embedded into the second-largest value when the pixel difference exceeds a predefined threshold.A similar embedding strategy is also applied to the minimum side of the block,including the second-smallest pixel value.This design enables each block to embed up to 14 bits of secret data.Experimental results demonstrate that the proposed method achieves significantly higher embedding capacity and improved visual quality compared to existing triple-stego RDH approaches,advancing the field of reversible steganography. 展开更多
关键词 RDH reversible data hiding PVO RDH base three stego images
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LLMKB:Large Language Models with Knowledge Base Augmentation for Conversational Recommendation
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作者 FANG Xiu QIU Sijia +1 位作者 SUN Guohao LU Jinhu 《Journal of Donghua University(English Edition)》 2026年第1期91-103,共13页
Conversational recommender systems(CRSs)focus on refining preferences and providing personalized recommendations through natural language interactions and dialogue history.Large language models(LLMs)have shown outstan... Conversational recommender systems(CRSs)focus on refining preferences and providing personalized recommendations through natural language interactions and dialogue history.Large language models(LLMs)have shown outstanding performance across various domains,thereby prompting researchers to investigate their applicability in recommendation systems.However,due to the lack of task-specific knowledge and an inefficient feature extraction process,LLMs still have suboptimal performance in recommendation tasks.Therefore,external knowledge sources,such as knowledge graphs(KGs)and knowledge bases(KBs),are often introduced to address the issue of data sparsity.Compared to KGs,KBs possess higher retrieval efficiency,making them more suitable for scenarios where LLMs serve as recommenders.To this end,we introduce a novel framework integrating LLMs with KBs for enhanced retrieval generation,namely LLMKB.LLMKB initially leverages structured knowledge to create mapping dictionaries,extracting entity-relation information from heterogeneous knowledge to construct KBs.Then,LLMKB achieves the embedding calibration between user information representations and documents in KBs through retrieval model fine-tuning.Finally,LLMKB employs retrievalaugmented generation to produce recommendations based on fused text inputs,followed by post-processing.Experiment results on two public CRS datasets demonstrate the effectiveness of our framework.Our code is publicly available at the link:https://anonymous.4open.science/r/LLMKB-6FD0. 展开更多
关键词 recommender system large language model(LLM) knowledge base(KB)
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Decoding the stoichiometry of surface Lewis acid/base sites:a pivotal aspect for tailoring selectivity in solar-driven CO_(2)reduction
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作者 Qinhui Guan Yuhao Guo +5 位作者 Shuting Li Xingjuan Li Xiao Li Xuan Liu Na Li Tingjiang Yan 《Science China Chemistry》 2026年第2期970-978,共9页
Lewis acid(LA)and Lewis base(LB)sites on catalyst surfaces play a pivotal role in catalytic reactions.By precisely modulating the type,density,and spatial distribution of these Lewis acid/base sites,catalytic performa... Lewis acid(LA)and Lewis base(LB)sites on catalyst surfaces play a pivotal role in catalytic reactions.By precisely modulating the type,density,and spatial distribution of these Lewis acid/base sites,catalytic performance indicators such as catalytic activity,selectivity,and stability can be effectively optimized.As a result,they become essential parameters that must be considered in the design and development of high-efficiency catalysts.This study proposes a surface engineering method to accurately control the concentration of surface LA and LB sites in defect-laden In_(2)O_(3-x)(OH)_(y)(denoted as N-n%-IO),establishing three types of LB/LA stoichiometric ratios with different photocatalytic CO_(2)hydrogenation performances.It is demonstrated that the LB-rich system(LB/LA>1)shows suppressed activity.In contrast,the balanced stoichiometric ratio system(LB/LA=1)attains an optimal methanol yield(179.79μmol g^(-1)h^(-1))and selectivity(43.67%),while the LA-rich system(LB/LA<1)exhibits the best CO production rate(1913.76μmol g^(-1)h^(-1))and selectivity(94.96%).Systematic experiments disclose that the balanced LB/LA system with adjacent surface frustrated Lewis pairs(SFLPs)can effectively facilitate the adsorption/activation of reactants,stabilize intermediates,and regulate the dynamic behavior of photo-generated carriers.However,the imbalanced LB/LA systems either lack necessary active sites or can only follow an oxygen vacancy-mediated pathway during photocatalytic CO_(2)hydrogenation.This work offers a comprehensive understanding of the crucial functions of surface Lewis acid/base sites in the product distribution of solar-driven CO_(2)reduction. 展开更多
关键词 Lewis acid Lewis base stoichiometric ratio CO_(2)reduction photocatalysis
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Towards mechanism-based tau-targeted therapies
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作者 Lidia Bakota Roland Brandt 《Neural Regeneration Research》 2026年第2期687-688,共2页
Tau plays a crucial role in several neurodegenerative diseases,collectively referred to as tauopathies.Therefore,targeting potential pathological changes in tau could enable useful therapeutic interventions.However,ta... Tau plays a crucial role in several neurodegenerative diseases,collectively referred to as tauopathies.Therefore,targeting potential pathological changes in tau could enable useful therapeutic interventions.However,tau is not an easy target because it dynamically interacts with microtubules and other cellular components,which presents a challenge for tau-targeted drugs.New cellular models could aid the development of mechanism-based tau-targeted therapies. 展开更多
关键词 tau targeted therapies cellular components mechanism based therapies cellular componentswhich cellular models MICROTUBULES TAUOPATHIES neurodegenerative diseasescollectively
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Correction:Flux‑based assessment of ozone visible foliar injury in Southern Alps
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作者 Elena Marra Alessandra De Marco +8 位作者 Andrea Ebone Anna Maria Ferrara Fabio Giannetti Francesco Tagliaferro Pierre Sicard Andrei Popa Ionel Popa Elena Paoletti Yasutomo Hoshika 《Journal of Forestry Research》 2026年第2期305-305,共1页
Correction to:Journal of Forestry Research(2025)36:124 https://doi.org/10.1007/s11676-025-01918-8 In this article the author’s name Yasutomo Hoshika was incorrectly written as Yasutoma Hoshika.The original article ha... Correction to:Journal of Forestry Research(2025)36:124 https://doi.org/10.1007/s11676-025-01918-8 In this article the author’s name Yasutomo Hoshika was incorrectly written as Yasutoma Hoshika.The original article has been corrected. 展开更多
关键词 visible foliar injury southern Alps flux based assessment yasutomo hoshika journal forestry research yasutoma hoshikathe OZONE
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Height-based biomass models differ for naturally regenerated and planted young trees
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作者 Peter Marcis Jozef Pajtík +1 位作者 Bohdan Konôpka Martin Lukac 《Forest Ecosystems》 2026年第1期178-187,共10页
This study investigated biomass allocation in young stands of European beech(Fagus sylvatica L.)and Norway spruce(Picea abies(L.)Karst.)across 31 forest sites in the Western Carpathians,Slovakia.A total of 541 trees a... This study investigated biomass allocation in young stands of European beech(Fagus sylvatica L.)and Norway spruce(Picea abies(L.)Karst.)across 31 forest sites in the Western Carpathians,Slovakia.A total of 541 trees aged 2–10 years,originating from natural regeneration and planting,were destructively sampled to quantify biomass in four components:foliage,branches,stems,and roots.Generalized non-linear least squares(GNLS)models with a weighing variance function outperformed log-transformed seemingly unrelated regression(SUR)models in terms of accuracy and robustness,especially for foliage and branch biomass.When using height as the predictor,SUR models tended to underestimate biomass in planted beech,leading to notable underprediction of aboveground and total biomass.Biomass allocation patterns varied significantly by species and regeneration origin.Using a non-linear system of equations and component ratio modelling,we found out that planted spruce displayed low variability and a consistent dominance of needle biomass,while naturally regenerated beech showed greater variability and a higher proportion of stem biomass,reflecting stronger competition-driven vertical growth.Interspecific differences in total biomass were more pronounced when using tree height,with spruce generally exhibiting greater biomass than beech at equivalent heights.Overall,stem base diameter marginally outperformed tree height as a predictor of biomass.However,tree height-based models showed strong performance and are particularly suitable for integration with remote sensing applications.These findings can directly support forest managers and modellers in comparing regeneration methods and biomass estimation approaches for early-stage stand development,carbon accounting,and remote sensing calibration. 展开更多
关键词 European beech Norway spruce Allometric relations Tree height Diameter at base Whole-tree biomass Tree components
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Secured-FL:Blockchain-Based Defense against Adversarial Attacks on Federated Learning Models
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作者 Bello Musa Yakubu Nor Shahida Mohd Jamail +1 位作者 Rabia Latif Seemab Latif 《Computers, Materials & Continua》 2026年第3期734-757,共24页
Federated Learning(FL)enables joint training over distributed devices without data exchange but is highly vulnerable to attacks by adversaries in the form of model poisoning and malicious update injection.This work pr... Federated Learning(FL)enables joint training over distributed devices without data exchange but is highly vulnerable to attacks by adversaries in the form of model poisoning and malicious update injection.This work proposes Secured-FL,a blockchain-based defensive framework that combines smart contract-based authentication,clustering-driven outlier elimination,and dynamic threshold adjustment to defend against adversarial attacks.The framework was implemented on a private Ethereum network with a Proof-of-Authority consensus algorithm to ensure tamper-resistant and auditable model updates.Large-scale simulation on the Cyber Data dataset,under up to 50%malicious client settings,demonstrates Secured-FL achieves 6%-12%higher accuracy,9%-15%lower latency,and approximately 14%less computational expense compared to the PPSS benchmark framework.Additional tests,including confusion matrices,ROC and Precision-Recall curves,and ablation tests,confirm the interpretability and robustness of the defense.Tests for scalability also show consistent performance up to 500 clients,affirming appropriateness to reasonably large deployments.These results make Secured-FL a feasible,adversarially resilient FL paradigm with promising potential for application in smart cities,medicine,and other mission-critical IoT deployments. 展开更多
关键词 Federated learning(FL) blockchain FL based privacy model defense FL model security ethereum smart contract
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Erratum:Marine Shell-Inspired Laser Surface Texturing:Characterizing the Surface Properties of Co-Based Alloy
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作者 Sefika Kasman Sertan Ozan 《Journal of Bionic Engineering》 2026年第1期551-551,共1页
The original online version of this article was revised:Several errors occurred in the published version of the article.These have now been corrected as follows:Page 2,section"2.2 Laser Texturing Procedure of Sur... The original online version of this article was revised:Several errors occurred in the published version of the article.These have now been corrected as follows:Page 2,section"2.2 Laser Texturing Procedure of Surfaces",line 2:The device name was corrected from"YDFLP-E-50-M8"to"YDFLP-50-M8."Page 3,Section 2.4:The phrase"95%confidence interval"has been corrected to"95%confidence level."Page 3,Figure 1 caption:The phrase"fandg"has been corrected to"f and g."The order"C4 and C12"has been reversed to"C12 and C4,"in accordance with the display order in the figure.Page 4,Figure reference:The phrase"Figs.4c and d"has been corrected to"Figs.5b and c."Page 5,paragraph starting with"The ANOVA results are presented...":The phrase"95%confidence interval"has been corrected to"95%confidence level." 展开更多
关键词 laser surface texturing surface properties marine shell inspired co based alloy laser texturing procedure confidence level ANOVA results
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Home-Based Care Service
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作者 XU JUNXING 《China Today》 2026年第3期70-72,共3页
Hebei Province has incorporated targeted assistance services for people with disabilities into livelihood projects,upgrading the quality and efficiency of support services for disadvantaged groups.THE living and nursi... Hebei Province has incorporated targeted assistance services for people with disabilities into livelihood projects,upgrading the quality and efficiency of support services for disadvantaged groups.THE living and nursing allowances provided by the Chinese government for people with disabilities who are unable to work are not only important components of China’s social security system which provide for the needs of its disabled,but also show China’s ability to guarantee the basic living standard and social fairness and justice for this group of people. 展开更多
关键词 livelihood projects home based care targeted assistance livelihood projectsupgrading people disabilities living nursing allowances targeted assistance services social security system
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Multimodal,multifaceted,imaging-based human brain white matter atlas
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作者 Junchen Zhou Wenxia Li +4 位作者 Shuo Xu Bharat B.Biswal Huafu Chen Jiao Li Wei Liao 《Science Bulletin》 2026年第3期500-504,共5页
The brain atlas,or parcellation-delineating spatial partitions,organizes the brain's structure and function[1].The spatial arrangements of highly heterogeneous landscapes represent specialized functional regions f... The brain atlas,or parcellation-delineating spatial partitions,organizes the brain's structure and function[1].The spatial arrangements of highly heterogeneous landscapes represent specialized functional regions for investigating their interactions.Early efforts to parcellate the mammalian brain,using histological cytoarchitecture and myeloarchitecture,as well as recent in vivo magnetic resonance imaging(MRl)[2,3],have primarily involved cortical areas,subcortical structures,and cerebellar nuclei.Human brain parcellations primarily focus on grey matter(GM),which purposefully excludes white matter(WM),hindering the development of next-generation brain atlases. 展开更多
关键词 brain atlasor cerebellar nucleihuman brain p vivo magnetic resonance imaging mrl human brain white matter atlas histological cytoarchitecture imaging based PARCELLATION MULTIMODAL
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Characterizations of g-Frames and g-Riesz Bases in Hilbert Spaces 被引量:37
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作者 Yu Can ZHU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2008年第10期1727-1736,共10页
In this paper, we introduce the pre-frame operator Q for the g-frame in a complex Hilbert space, which will play a key role in studying g-frames and g-Riesz bases etc. Using the pre-frame operator Q, we give some nece... In this paper, we introduce the pre-frame operator Q for the g-frame in a complex Hilbert space, which will play a key role in studying g-frames and g-Riesz bases etc. Using the pre-frame operator Q, we give some necessary and sufficient conditions for a g-Bessel sequence, a g-frame, and a g-Riesz basis in a complex Hilbert space, which have properties similar to those of the Bessel sequence, frame, and Riesz basis respectively. We also obtain the relation between a g-frame and a g-Riesz basis, and the relation of bounds between a g-frame and a g-Riesz basis. Lastly, we consider the stability of a g-frame or a g-Riesz basis for a Hilbert space under perturbation. 展开更多
关键词 FRAME g-Bessel sequence G-FRAME g-riesz basis
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含Tröger’s base结构聚(苯并噁唑-酰亚胺)热重排分离膜的制备与其气体分离特性研究
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作者 宋映晓 唐傲 +3 位作者 张家霖 董杰 赵昕 张清华 《高分子学报》 北大核心 2025年第8期1358-1368,共11页
设计合成了一种新型含Tröger’s base(TB)结构的二胺单体—2,8-二氨基-4,10-二甲基-6,12-氢-5,11-亚甲二苯并[1,5]二氮辛(TBDA),并将其与2,2′-双(3,4-二羧酸)六氟丙烷二酐(6FDA)和2,2-双(3-氨基-4-羟基苯基)六氟丙烷(APAF)共聚反... 设计合成了一种新型含Tröger’s base(TB)结构的二胺单体—2,8-二氨基-4,10-二甲基-6,12-氢-5,11-亚甲二苯并[1,5]二氮辛(TBDA),并将其与2,2′-双(3,4-二羧酸)六氟丙烷二酐(6FDA)和2,2-双(3-氨基-4-羟基苯基)六氟丙烷(APAF)共聚反应,合成了一系列含邻羟基酰亚胺单元的聚酰亚胺(HPI).在高温下对HPI膜进行热重排处理,获得了兼具TB自聚微孔结构和热重排结构的聚(苯并噁唑-酰亚胺)气体分离膜.研究结果显示,TB自具微孔结构和热重排结构的协同作用抑制了分子链的规整堆砌,使分离膜自由体积增加,从而赋予其优异的气体分离特性.经430℃热重排反应的6FTB1-TR430膜表现出最优异的综合气体分离性能,对CO_(2)、CH_(4)、O_(2)和N_(2)的渗透系数分别为267.6、7.0、57.2和12.5 Barrer(1 Barrer=7.5×10^(−14) cm^(3)(STP)/(cm^(2)·s·Pa),STP表示标准状态,即0℃,1.01×10^(5)Pa),同时,选择性分别达到α(CO_(2)/CH_(4))=38.2及α(O_(2)/N_(2))=4.6.此外,该类分离膜的热分解温度为530~560℃,玻璃化转变温度(Tg)超过400℃,显示出优异的热稳定性.该研究为设计和开发聚酰亚胺类高效气体分离膜提供了新的思路. 展开更多
关键词 Tröger’s base结构 热重排反应 协同作用 气体分离膜
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Enhancing resistance to bacterial blight in rice using CRISPR-based base editing technology 被引量:1
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作者 Chenhao Li Bo Liu +1 位作者 Hansong Dong Bing Yang 《The Crop Journal》 2025年第1期115-124,共10页
Bacterial blight(BB),caused by Xanthomonas oryzae pathovar oryzae(Xoo),poses a significant threat to rice production,particularly in Asia and West Africa.Breeding resistance against BB in elite rice varieties is cruci... Bacterial blight(BB),caused by Xanthomonas oryzae pathovar oryzae(Xoo),poses a significant threat to rice production,particularly in Asia and West Africa.Breeding resistance against BB in elite rice varieties is crucial to advancing rice breeding program and supporting smallholder farmers.Transcription Activator-Like effectors(TALes)are key virulence factors in Xoo,with some targeting the susceptibility(S)genes such as the sugar transporter SWEET genes in rice.Among these,SWEET14 is an important S gene,with its promoter bound by the TALe TalC which exists across all sequenced African Xoo isolates.In the present study,we utilized CRISPR/Cas9-based cytidine and adenine base editors to alter the effector binding element(EBE)of TalC in the promoter of SWEET14 in rice cultivars Kitaake,IR24,and Zhonghua 11.Mutations with C to T changes in EBE led to reduced SWEET14 induction by TalC-containing Xoo strains,resulting in resistance to African Xoo isolates reliant on TalC for virulence.Conversely,A to G changes retained SWEET14 inducibility and susceptibility to Xoo in edited lines.Importantly,no off-target mutations were detected at predicted sites,and the edited lines exhibited no obvious defects in major agronomic traits in Kitaake.These results underscore the effectiveness of base editing systems for both molecular biology research and crop improvement endeavors. 展开更多
关键词 base editing base editors CBE and ABE Rice improvement Bacterial blight resistance
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RUNX2 is essential for maintaining synchondrosis chondrocytes and cranial base growth 被引量:1
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作者 Shawn A.Hallett Ashley Dixon +9 位作者 Isabella Marrale Lena Batoon JoséBrenes Annabelle Zhou Ariel Arbiv Vesa Kaartinen Benjamin Allen Wanida Ono Renny T.Franceschi Noriaki Ono 《Bone Research》 2025年第4期939-956,共18页
The cranial base synchondroses,comprised of opposite-facing bidirectional chondrocyte layers,drive anteroposterior cranial base growth.In humans,RUNX2 haploinsufficiency causes cleidocranial dysplasia associated with ... The cranial base synchondroses,comprised of opposite-facing bidirectional chondrocyte layers,drive anteroposterior cranial base growth.In humans,RUNX2 haploinsufficiency causes cleidocranial dysplasia associated with deficient midfacial growth.However,how RUNX2 regulates chondrocytes in the cranial base synchondroses remains unknown.To address this,we inactivated Runx2 in postnatal synchondrosis chondrocytes using a tamoxifen-inducible Fgfr3-creER(Fgfr3-Runx2cKO)mouse model.Fgfr3-Runx2cKO mice displayed skeletal dwarfism and reduced anteroposterior cranial base growth associated with premature synchondrosis ossification due to impaired chondrocyte proliferation,accelerated hypertrophy,apoptosis,and osteoclast-mediated cartilage resorption.Lineage tracing reveals that Runx2-deficient Fgfr3+cells failed to differentiate into osteoblasts.Notably,Runx2-deficient chondrocytes showed an elevated level of FGFR3 and its downstream signaling components,pERK1/2 and SOX9,suggesting that RUNX2 downregulates FGFR3 in the synchondrosis.This study unveils a new role of Runx2 in cranial base chondrocytes,identifying a possible RUNX2-FGFR3-MAPK-SOX9 signaling axis that may control cranial base growth. 展开更多
关键词 cranial base synchondroses chondrocyte proliferation HYPERTROPHY cleidocranial dysplasia cranial base synchondrosescomprised apoptosis inactivated runx RUNX
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A Dynamic Knowledge Base Updating Mechanism-Based Retrieval-Augmented Generation Framework for Intelligent Question-and-Answer Systems 被引量:1
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作者 Yu Li 《Journal of Computer and Communications》 2025年第1期41-58,共18页
In the context of power generation companies, vast amounts of specialized data and expert knowledge have been accumulated. However, challenges such as data silos and fragmented knowledge hinder the effective utilizati... In the context of power generation companies, vast amounts of specialized data and expert knowledge have been accumulated. However, challenges such as data silos and fragmented knowledge hinder the effective utilization of this information. This study proposes a novel framework for intelligent Question-and-Answer (Q&A) systems based on Retrieval-Augmented Generation (RAG) to address these issues. The system efficiently acquires domain-specific knowledge by leveraging external databases, including Relational Databases (RDBs) and graph databases, without additional fine-tuning for Large Language Models (LLMs). Crucially, the framework integrates a Dynamic Knowledge Base Updating Mechanism (DKBUM) and a Weighted Context-Aware Similarity (WCAS) method to enhance retrieval accuracy and mitigate inherent limitations of LLMs, such as hallucinations and lack of specialization. Additionally, the proposed DKBUM dynamically adjusts knowledge weights within the database, ensuring that the most recent and relevant information is utilized, while WCAS refines the alignment between queries and knowledge items by enhanced context understanding. Experimental validation demonstrates that the system can generate timely, accurate, and context-sensitive responses, making it a robust solution for managing complex business logic in specialized industries. 展开更多
关键词 Retrieval-Augmented Generation Question-and-Answer Large Language Models Dynamic Knowledge base Updating Mechanism Weighted Context-Aware Similarity
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NeOR: neural exploration with feature-based visual odometry and tracking-failure-reduction policy 被引量:1
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作者 ZHU Ziheng LIU Jialing +2 位作者 CHEN Kaiqi TONG Qiyi LIU Ruyu 《Optoelectronics Letters》 2025年第5期290-297,共8页
Embodied visual exploration is critical for building intelligent visual agents. This paper presents the neural exploration with feature-based visual odometry and tracking-failure-reduction policy(Ne OR), a framework f... Embodied visual exploration is critical for building intelligent visual agents. This paper presents the neural exploration with feature-based visual odometry and tracking-failure-reduction policy(Ne OR), a framework for embodied visual exploration that possesses the efficient exploration capabilities of deep reinforcement learning(DRL)-based exploration policies and leverages feature-based visual odometry(VO) for more accurate mapping and positioning results. An improved local policy is also proposed to reduce tracking failures of feature-based VO in weakly textured scenes through a refined multi-discrete action space, keyframe fusion, and an auxiliary task. The experimental results demonstrate that Ne OR has better mapping and positioning accuracy compared to other entirely learning-based exploration frameworks and improves the robustness of feature-based VO by significantly reducing tracking failures in weakly textured scenes. 展开更多
关键词 intelligent visual agents deep reinforcement learning drl based embodied visual exploration feature based visual odometry tracking failure reduction policy neural exploration deep reinforcement learning
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Evolutionary Particle Swarm Optimization Algorithm Based on Collective Prediction for Deployment of Base Stations
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作者 Jiaying Shen Donglin Zhu +5 位作者 Yujia Liu Leyi Wang Jialing Hu Zhaolong Ouyang Changjun Zhou Taiyong Li 《Computers, Materials & Continua》 SCIE EI 2025年第1期345-369,共25页
The wireless signals emitted by base stations serve as a vital link connecting people in today’s society and have been occupying an increasingly important role in real life.The development of the Internet of Things(I... The wireless signals emitted by base stations serve as a vital link connecting people in today’s society and have been occupying an increasingly important role in real life.The development of the Internet of Things(IoT)relies on the support of base stations,which provide a solid foundation for achieving a more intelligent way of living.In a specific area,achieving higher signal coverage with fewer base stations has become an urgent problem.Therefore,this article focuses on the effective coverage area of base station signals and proposes a novel Evolutionary Particle Swarm Optimization(EPSO)algorithm based on collective prediction,referred to herein as ECPPSO.Introducing a new strategy called neighbor-based evolution prediction(NEP)addresses the issue of premature convergence often encountered by PSO.ECPPSO also employs a strengthening evolution(SE)strategy to enhance the algorithm’s global search capability and efficiency,ensuring enhanced robustness and a faster convergence speed when solving complex optimization problems.To better adapt to the actual communication needs of base stations,this article conducts simulation experiments by changing the number of base stations.The experimental results demonstrate thatunder the conditionof 50 ormore base stations,ECPPSOconsistently achieves the best coverage rate exceeding 95%,peaking at 99.4400%when the number of base stations reaches 80.These results validate the optimization capability of the ECPPSO algorithm,proving its feasibility and effectiveness.Further ablative experiments and comparisons with other algorithms highlight the advantages of ECPPSO. 展开更多
关键词 Particle swarm optimization effective coverage area global optimization base station deployment
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结合Diffusion-Based WGANGP的变压器油纸绝缘老化状态拉曼光谱检测方法 被引量:3
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作者 陈新岗 敖怡 +5 位作者 张知先 马志鹏 张文轩 万福 况露 罗博文 《光谱学与光谱分析》 北大核心 2025年第8期2164-2173,共10页
提出了一种结合拉曼光谱与扩散模型改进的Wasserstein生成对抗网络(WGANGP)方法,用于提高变压器油纸绝缘老化状态的检测精度。凭借拉曼光谱技术无接触、不损耗的优势,可通过其分析油浸式电力变压器内部油纸绝缘材料的老化产物来评估变... 提出了一种结合拉曼光谱与扩散模型改进的Wasserstein生成对抗网络(WGANGP)方法,用于提高变压器油纸绝缘老化状态的检测精度。凭借拉曼光谱技术无接触、不损耗的优势,可通过其分析油浸式电力变压器内部油纸绝缘材料的老化产物来评估变压器的老化程度。结合深度学习分类模型简化了拉曼光谱数据预处理过程,但此类模型对训练数据的数量和质量有较高要求,由于热加速老化实验周期长,导致可用于训练的有效拉曼光谱数据集相对稀少,限制了分类模型性能。为了解决这一难题,本研究引入了一种新的数据增强方法,即基于扩散模型的WGANGP(Diffusion-Based WGANGP),该方法通过将去噪扩散概率模型的前向加噪过程与WGANGP相结合,向WGANGP中引入实例化的噪声,去除了传统WGANGP的生成器结构中的复杂向上采样过程,简化了数据增强模型结构,有利于模型参数优化。相比于传统GAN及其变体,这种方法不仅保持了变压器油纸绝缘老化样本拉曼光谱数据集的原始特征峰特征与老化程度相关的基线漂移趋势,且与原始数据集特征保持近似的空间分布,生成的数据集信噪比(SNR)为24.84 dB,相比于原始数据集提高了32.11%;同时,也提升了生成样本的多样性,提高了基于深度学习的老化诊断模型的泛化能力、定量分析能力和鲁棒性。实验结果表明,采用Diffusion-Based WGANGP数据增强模型所生成的拉曼光谱数据集,在多个分类模型上的表现均优于其他数据增强方法,特别是在与ResNet-SVM分类模型结合时,在Accuracy(准确性,0.9974)、F1 score(F1分数,0.9969)、Recall(召回率,0.9960)和Precision(精确度,0.9980)四个评价指标上均表现出优势,这表明改进后的数据增强模型能够有效解决变压器老化绝缘油样本稀缺的问题,同时提高了分类模型对变压器老化状态的定量诊断能力。 展开更多
关键词 变压器 油纸绝缘 拉曼光谱 Diffusion-based WGANGP 故障诊断
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Triphenylamine-Based Schiff Base Compounds for the Latent Fingerprints Visualization
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作者 Chen Fafen Chen Chunlin +7 位作者 Peng Zhi Zhang Bangcui Luo Haiyan Li Shan Gao Shulin Wang Jianfei Li Xiangguang Yang Yanhua 《有机化学》 北大核心 2025年第11期4185-4194,共10页
To further advance the development of the fluorescent dyes for latent fingerprint imaging,two triphenylamine-based Schiff base compounds containing a benzimidazole group(TPA-BZI)and a phenyl unit(TPA-Ph)were designed ... To further advance the development of the fluorescent dyes for latent fingerprint imaging,two triphenylamine-based Schiff base compounds containing a benzimidazole group(TPA-BZI)and a phenyl unit(TPA-Ph)were designed and synthesized.Photoluminescence experiments revealed that both compounds exhibited solvatochromism and intramolecular charge transfer(ICT)characteristics in six organic solvents.Additionally,they showed aggregation-induced emission(AIE)in CH_(3)OH/water mixtures and solid-state fluorescence.These phenomena were further elucidated through time-dependent density functional theory(TD-DFT)calculations.It was also found that the two compounds could be used for latent fingerprints imaging,and could easily distinguish the details of fingerprints from Ⅰ to Ⅲ levels,which could provide the preliminary evidence to match personal identification. 展开更多
关键词 Schiff bases triphenylamine-based compounds aggregation-induced emission latent fingerprints imaging
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