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Application of response surface method for optimal transfer conditions of multi-layer ceramic capacitor alignment system
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作者 PARK Su-seong KIM Jae-min +1 位作者 CHUNG Won-jee SHIN O-chul 《Journal of Central South University》 SCIE EI CAS 2011年第3期726-730,共5页
The multi-layer ceramic capacitor (MLCC) alignment system aims at the inter-process automation between the first and the second plastic processes.As a result of testing performance verification of MLCC alignment syste... The multi-layer ceramic capacitor (MLCC) alignment system aims at the inter-process automation between the first and the second plastic processes.As a result of testing performance verification of MLCC alignment system,the average alignment rates are 95% for 3216 chip,88.5% for 2012 chip and 90.8% for 3818 chip.The MLCC alignment system can be accepted for practical use because the average manual alignment is just 80%.In other words,the developed MLCC alignment system has been upgraded to a great extent,compared with manual alignment.Based on the successfully developed MLCC alignment system,the optimal transfer conditions have been explored by using RSM.The simulations using ADAMS has been performed according to the cube model of CCD.By using MiniTAB,the model of response surface has been established based on the simulation results.The optimal conditions resulted from the response optimization tool of MiniTAB has been verified by being assigned to the prototype of MLCC alignment system. 展开更多
关键词 multi-layer ceramic capacitor (MLCC) alignment system response surface method (RSM) MiniTAB ADAMS
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A novel posture alignment system for aircraft wing assembly 被引量:17
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作者 Bin ZHANG Bao-guo YAO Ying-lin KE 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第11期1624-1630,共7页
A novel 6-degree of freedom (DOF) posture alignment system, based on 3-DOF positioners, is presented for the assembly of aircraft wings. Each positioner is connected with the wing through a rotational and adsorptive h... A novel 6-degree of freedom (DOF) posture alignment system, based on 3-DOF positioners, is presented for the assembly of aircraft wings. Each positioner is connected with the wing through a rotational and adsorptive half-ball shaped end-effector, and the positioners together with the wing are considered as a 3-PPPS (P denotes a prismatic joint and S denotes a spherical joint) redundantly actuated parallel mechanism. The kinematic model of this system is established and a trajectory planning method is introduced. A complete analysis of inverse dynamics is carried out with the Newton-Euler algorithm, which is used to find the desired actuating torque in the design and path planning phase. Simulation analysis of the displacement and actuating torque of each joint of the positioners based on inverse kinematics and dynamics is conducted, and the results show that the system is feasible for the posture alignment of aircraft wings. 展开更多
关键词 Aircraft wings Three-coordinate positioner Posture alignment KINEMATICS Dynamics
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A laser shaft alignment system with dual PSDs 被引量:5
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作者 JIAO Guo-hua LI Yu-lin +2 位作者 ZHANG Dong-bo LI Tong-hai HU Bao-wen 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第10期1772-1776,共5页
Shaft alignment is an important technique during installation and maintenance of a rotating machine. A high-precision laser alignment system has been designed with dual PSDs (Position Sensing Detector) to change tradi... Shaft alignment is an important technique during installation and maintenance of a rotating machine. A high-precision laser alignment system has been designed with dual PSDs (Position Sensing Detector) to change traditional manual way of shaft alignment and to make the measurement easier and more accurate. The system is comprised of two small measuring units (laser transmitter and detector) and a PDA (Personal Digital Assistant) with measurement software. The laser alignment system with dual PSDs was improved on a single PSD system, and yields higher measurement accuracy than the previous design, and has been successful for designing and implements actual shaft alignment. In the system, the range of offset measurement is ±4 mm, and the resolution is 1.5 μm, with accuracy being less than 2 μm. 展开更多
关键词 Rotating machine Shaft alignment Laser alignment Position sensing detector (PSD) Laser micro-displacement measurement
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Stiffness of Postural Alignment System Based on 3-Axis Actuators for Large Aircraft Components 被引量:4
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作者 GUO Zhimin JIANG Junxia KE Yinglin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第4期524-531,共8页
Aircraft digital flexible assembly fixture and technologies are widely used in developed countries, while the traditional jig-based assembly mode is still used in China. The application study of aircraft digital flexi... Aircraft digital flexible assembly fixture and technologies are widely used in developed countries, while the traditional jig-based assembly mode is still used in China. The application study of aircraft digital flexible assembly system is just beginning in our country recently. To meet the requirements of automated posture alignment and join in digital assembly system for large aircraft components, a novel fitting fixture called 3-axis actuator is developed. On the basis of the actuators, three kinds of posture alignment system for large aircraft components are proposed, including the non-redundant system, the redundant actuating system, and the redundant leg system, and their constitutions and properties are introduced. Through deriving the feeding transmission stiffness model of single actuator and analyzing the inverse kinematics of these systems, the relationship between the external force and the changes of position and orientation of large aircraft component is obtained, and then the postural alignment stiffness models are established. With the method mentioned above, the postural alignment stiffness of three systems is computed by using the algebraic formulate, and the results show that redundant properties can increase system's postural alignment stiffness. As an example, a optimized layout of the assembly system for a given model of aircraft is developed, the results of application show that the layout has many advantages, such as high accuracy, stiffness, stability, reliability, efficiency and flexible, which can satisfy the requirement of aircraft digital assembly system well. The proposed study of postural alignment stiffness for different systems can supply the theoretic support for the optimization layout design of aircraft digital assembly system, and contribute to evaluate the system working performance of systems. 展开更多
关键词 3-axis actuator large aircraft component redundant postural alignment stiffness posture-holding
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The Laser Shaft Alignment System with Dual PSDs 被引量:1
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作者 JIAO Guohua 1,2 ,LI Yulin1,ZHANG Dongbo3,LI Tonghai1,HU Baowen1 (1.Xian Institute of Optics and Precision Mechanics of CAS,Xi’an 710068,China 2.Graduate School of the Chinese Academy of Sciences,Beijing 100039,China 3.The 16th Institute of CATEC,Xi’an 710100,China) 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S1期107-111,共5页
Shaft alignment is an important technique during installation and maintenance of a rotating machine. A high-precision laser alignment system has been designed with dual PSDs (Position Sensing Detector) to change tradi... Shaft alignment is an important technique during installation and maintenance of a rotating machine. A high-precision laser alignment system has been designed with dual PSDs (Position Sensing Detector) to change traditional manual way of shaft alignment and to make the measurement easier and more accurate. The system is comprised of two small measuring units (laser transmitter and detector) and a PDA (Personal Digital Assistant) with the measurement software. The laser alignment system with dual PSDs was improved on a single PSD system,and it gets higher measurement accuracy than the previous design,and it has been succeeded in designing and implement for actual shaft alignment. In the system,the range of offset measurement is ±4 mm,and the resolution is 1.5 μm,and the accuracy is less than 2 μm. 展开更多
关键词 ROTATING machine SHAFT alignment LASER alignment POSITION sensing detector (PSD) LASER micro-displac
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Implementation of Autofocus in Alignment System for Layered Imprint Fabrication
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作者 王权岱 段玉岗 +2 位作者 卢秉恒 向家伟 杨连发 《Transactions of Tianjin University》 EI CAS 2009年第4期294-299,共6页
Autofocus method based on the analysis of image content information is investigated to reduce the alignment error resulting from mark positioning uncertainty due to defocus in microstructure layered fabrication proces... Autofocus method based on the analysis of image content information is investigated to reduce the alignment error resulting from mark positioning uncertainty due to defocus in microstructure layered fabrication process based on multilevel imprint lithography. The applicability of several autofocus functions to the alignment mark images is evaluated concerning their uniformity, sharpness near peak, reliability and measure computation efficiency and the most suitable one based on power spectrum in frequency domain (PSFD) is adopted. To solve the problem of too much computation amount needed in PSFD algorithm, the strategy of interested region detection and effective image reconstruction is proposed and the algorithm efficiency is improved. The test results show that the computation time is reduced from 0.316 s to 0.023 s under the same conditions while the other merits of the function are preserved, which indicates that the modified algorithm can meet the mark image autofocusing requirements in response time, accuracy and robustness. The alignment error due to defocus which is about 0.5 μm indicated by experimental results can be reduced or eliminated by the autofocusing implementation. 展开更多
关键词 autofocus algorithm alignment imprint lithography layered fabrication
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SmartAxis,a software for accurate and rapid zone axis alignment of nanocrystalline materials 被引量:1
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作者 Jinfei Zhou Yujiao Wang +7 位作者 Binbin Lu Jia Lyu Nini Wei Jianfeng Huang Lingmei Liu Xiao Li Xinghua Li Daliang Zhang 《Nano Materials Science》 2025年第2期297-303,共7页
Nanocrystals have emerged as cutting-edge functional materials benefiting from the increased surface and enhanced coupling of electronic states.High-resolution imaging in transmission electron microscope can provide i... Nanocrystals have emerged as cutting-edge functional materials benefiting from the increased surface and enhanced coupling of electronic states.High-resolution imaging in transmission electron microscope can provide invaluable structural information of crystalline materials,albeit it remains greatly challenging to nanocrystals due to the arduousness of accurate zone axis adjustment.Herein,a homemade software package,called SmartAxis,is developed for rapid yet accurate zone axis alignment of nanocrystals.Incident electron beam tilt is employed as an eccentric goniometer to measure the angular deviation of a crystal to a zone axis,and then serves as a linkage to calculate theαandβtilts of goniometer based on an accurate quantitative relationship.In this way,high-resolution imaging of one identical small Au nanocrystal,as well as electron beam-sensitive MIL-101 metal-organic framework crystals,along multiple zone axes,was performed successfully by using this accurate,time-and electron dose-saving zone axis alignment software package. 展开更多
关键词 Zone axis alignment NANOCRYSTALS Beam tilt Electron beam-sensitive materials
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Epitaxial growth of full-vdW α-In_(2)Se_(3)/MoS_(2) heterostructures for all-in-one sensing and memory-computing artificial visual system 被引量:1
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作者 Zheng Zhang Lei Shi +6 位作者 Bin Wang Jingyuan Qu Xiaoling Wang Tao Wang Qitao Jiang Wuhong Xue Xiaohong Xu 《Chinese Chemical Letters》 2025年第3期570-575,共6页
Van der Waals(vdW)ferroelectric-semiconductor heterojunction provides reconfigurable band alignment based on optical/electrical-assisted polarization switching,which shows great potential to construct artificial visua... Van der Waals(vdW)ferroelectric-semiconductor heterojunction provides reconfigurable band alignment based on optical/electrical-assisted polarization switching,which shows great potential to construct artificial visual neural systems.However,the mechanical exfoliation fabrication scheme for proof-of-concept demonstrations and fundamental studies is cumbersome and not scalable for practical application.Here,we present a synthetic strategy for the large-scale and high crystallinity growth of planar/verticalα-In_(2)Se_(3)/MoS_(2)heterojunctions by dynamically tuning the growth temperature.Furthermore,based on theα-In_(2)Se_(3)/MoS_(2)heterostructures,photo-synapse devices are designed and fabricated to simulate visual neural systems functions,including multistate storage,optical logic operation,potentiation and depression,paired-pulse facilitation(PPF),short-term memory(STM),long-term memory(LTM),and Learning-Forgetting-Relearning.By coupling the spatiotemporally relevant optical and electric information,the device can mimic the superior biological visual system’s light adaptation and Pavlovian conditioning.This work provides a strategy for dynamically tuning the orientation of ferroelectric-semiconductor heterojunction stacks and will give impetus to applying all-in-one sensing and memory-computing artificial vision systems. 展开更多
关键词 Heterojunction Ferroelectric α-In_(2)Se_(3)/MoS_(2) Band alignment OPTOELECTRONIC Artificial vision system
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Uniaxial alignment of perovskite nanowires via brush painting technique for efficient flexible polarized photodetectors 被引量:1
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作者 Mi Kyong Kim Su Min Park +8 位作者 Haedam Jin Jeongbeom Cha Dohun Baek Tae Oh Yoon Gibaek Lee Se Gyo Han Sae Byeok Jo Seok Joo Yang Min Kim 《Journal of Materials Science & Technology》 2025年第4期24-33,共10页
A polarization-sensitive and flexible photodetector was fabricated through the precise alignment of perovskite nanowires(NWs)using a brush coating technique.The alignment of the NWs was meticulously examined,consideri... A polarization-sensitive and flexible photodetector was fabricated through the precise alignment of perovskite nanowires(NWs)using a brush coating technique.The alignment of the NWs was meticulously examined,considering various chemical properties of the solvent,such as boiling point,viscosity,and surface tension.Notably,when the NWs were brush-coated with toluene dispersion,the NWs were aligned in higher order than those processed from octane dispersion.The degree of alignment was correlated with the photodetector property.Especially,the well-aligned NW photodetector exhibited a two-fold disparity in current response contingent on the polarization direction.Furthermore,even after enduring 500 bending cycles,the device retained 80%of its photodetector performance.This approach underscores the potential of solution-processed flexible photodetectors for advanced optical applications under dynamic operating conditions. 展开更多
关键词 Perovskite photodetectors Perovskite nanowires Brush coating technique Aligned nanowires
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Joint Feature Encoding and Task Alignment Mechanism for Emotion-Cause Pair Extraction
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作者 Shi Li Didi Sun 《Computers, Materials & Continua》 SCIE EI 2025年第1期1069-1086,共18页
With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant importance.Emotion-cause pair extraction enables the identification of causal relationships between emotions... With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant importance.Emotion-cause pair extraction enables the identification of causal relationships between emotions and their triggers within a text,facilitating a deeper understanding of expressed sentiments and their underlying reasons.This comprehension is crucial for making informed strategic decisions in various business and societal contexts.However,recent research approaches employing multi-task learning frameworks for modeling often face challenges such as the inability to simultaneouslymodel extracted features and their interactions,or inconsistencies in label prediction between emotion-cause pair extraction and independent assistant tasks like emotion and cause extraction.To address these issues,this study proposes an emotion-cause pair extraction methodology that incorporates joint feature encoding and task alignment mechanisms.The model consists of two primary components:First,joint feature encoding simultaneously generates features for emotion-cause pairs and clauses,enhancing feature interactions between emotion clauses,cause clauses,and emotion-cause pairs.Second,the task alignment technique is applied to reduce the labeling distance between emotion-cause pair extraction and the two assistant tasks,capturing deep semantic information interactions among tasks.The proposed method is evaluated on a Chinese benchmark corpus using 10-fold cross-validation,assessing key performance metrics such as precision,recall,and F1 score.Experimental results demonstrate that the model achieves an F1 score of 76.05%,surpassing the state-of-the-art by 1.03%.The proposed model exhibits significant improvements in emotion-cause pair extraction(ECPE)and cause extraction(CE)compared to existing methods,validating its effectiveness.This research introduces a novel approach based on joint feature encoding and task alignment mechanisms,contributing to advancements in emotion-cause pair extraction.However,the study’s limitation lies in the data sources,potentially restricting the generalizability of the findings. 展开更多
关键词 Emotion-cause pair extraction interactive information enhancement joint feature encoding label consistency task alignment mechanisms
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In-depth understanding of the band alignment and interface states scenario in Bi_(2)O_(2)Se/SrTiO_(3) ultrathin heterojunction
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作者 Ke Zhang Yu-Sen Feng +6 位作者 Lei Hao Jing Mi Miao Du Ming-Hui Xu Yan Zhao Jian-Ping Meng Liang Qiao 《Rare Metals》 2025年第2期1204-1212,共9页
Bismuth oxyselenide(Bi_(2)O_(2)Se),a novel quasi-two-dimensional charge-carrying semiconductor,is recognized as one of the most promising emerging platforms for next-generation semiconductor devices.Recent advancement... Bismuth oxyselenide(Bi_(2)O_(2)Se),a novel quasi-two-dimensional charge-carrying semiconductor,is recognized as one of the most promising emerging platforms for next-generation semiconductor devices.Recent advancements in the development of diverse Bi_(2)O_(2)Se heterojunctions have unveiled extensive potential applications in both electronics and optoelectronics.However,achieving an in-depth understanding of band alignment and particularly interface dynamics remains a significant challenge.In this study,we conduct a comprehensive experimental investigation into band alignment utilizing high-resolution X-ray photoelectron spectroscopy(HRXPS),while also thoroughly discussing the properties of interface states.Our findings reveal that ultrathin films of Bi_(2)O_(2)Se grown on SrTiO_(3)(with TiO_(2)(001)termination)exhibit Type-I(straddling gap)band alignment characterized by a valence band offset(VBO)of approximately 1.77±0.04 eV and a conduction band offset(CBO)around 0.68±0.04 eV.Notably,when accounting for the influence of interface states,the bands at the interface display a herringbone configuration due to substantial built-in electric fields,which markedly deviate from conventional band alignments.Thus,our results provide valuable insights for advancing high-efficiency electronic and optoelectronic devices,particularly those where charge transfer is highly sensitive to interface states. 展开更多
关键词 Bismuth oxyselenide HETEROJUNCTIONS Band alignment Interface states Build-in electrical field
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Beyond Intentions:A Critical Survey of Misalignment in LLMs
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作者 Yubin Qu Song Huang +2 位作者 Long Li Peng Nie Yongming Yao 《Computers, Materials & Continua》 2025年第10期249-300,共52页
Large language models(LLMs)represent significant advancements in artificial intelligence.However,their increasing capabilities come with a serious challenge:misalignment,which refers to the deviation of model behavior... Large language models(LLMs)represent significant advancements in artificial intelligence.However,their increasing capabilities come with a serious challenge:misalignment,which refers to the deviation of model behavior from the designers’intentions and human values.This review aims to synthesize the current understanding of the LLM misalignment issue and provide researchers and practitioners with a comprehensive overview.We define the concept of misalignment and elaborate on its various manifestations,including generating harmful content,factual errors(hallucinations),propagating biases,failing to follow instructions,emerging deceptive behaviors,and emergent misalignment.We explore the multifaceted causes of misalignment,systematically analyzing factors from surface-level technical issues(e.g.,training data,objective function design,model scaling)to deeper fundamental challenges(e.g.,difficulties formalizing values,discrepancies between training signals and real intentions).This review covers existing and emerging techniques for detecting and evaluating the degree of misalignment,such as benchmark tests,red-teaming,and formal safety assessments.Subsequently,we examine strategies to mitigate misalignment,focusing on mainstream alignment techniques such as RLHF,Constitutional AI(CAI),instruction fine-tuning,and novel approaches that address scalability and robustness.In particular,we analyze recent advances in misalignment attack research,including system prompt modifications,supervised fine-tuning,self-supervised representation attacks,and model editing,which challenge the robustness of model alignment.We categorize and analyze the surveyed literature,highlighting major findings,persistent limitations,and current contentious points.Finally,we identify key open questions and propose several promising future research directions,including constructing high-quality alignment datasets,exploring novel alignment methods,coordinating diverse values,and delving into the deep philosophical aspects of alignment.This work underscores the complexity and multidimensionality of LLM misalignment issues,calling for interdisciplinary approaches to reliably align LLMs with human values. 展开更多
关键词 Large language models alignment MISalignment AI safety human values
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Multi-Modal Pre-Synergistic Fusion Entity Alignment Based on Mutual Information Strategy Optimization
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作者 Huayu Li Xinxin Chen +3 位作者 Lizhuang Tan Konstantin I.Kostromitin Athanasios V.Vasilakos Peiying Zhang 《Computers, Materials & Continua》 2025年第11期4133-4153,共21页
To address the challenge of missing modal information in entity alignment and to mitigate information loss or bias arising frommodal heterogeneity during fusion,while also capturing shared information acrossmodalities... To address the challenge of missing modal information in entity alignment and to mitigate information loss or bias arising frommodal heterogeneity during fusion,while also capturing shared information acrossmodalities,this paper proposes a Multi-modal Pre-synergistic Entity Alignmentmodel based on Cross-modalMutual Information Strategy Optimization(MPSEA).The model first employs independent encoders to process multi-modal features,including text,images,and numerical values.Next,a multi-modal pre-synergistic fusion mechanism integrates graph structural and visual modal features into the textual modality as preparatory information.This pre-fusion strategy enables unified perception of heterogeneous modalities at the model’s initial stage,reducing discrepancies during the fusion process.Finally,using cross-modal deep perception reinforcement learning,the model achieves adaptive multilevel feature fusion between modalities,supporting learningmore effective alignment strategies.Extensive experiments on multiple public datasets show that the MPSEA method achieves gains of up to 7% in Hits@1 and 8.2% in MRR on the FBDB15K dataset,and up to 9.1% in Hits@1 and 7.7% in MRR on the FBYG15K dataset,compared to existing state-of-the-art methods.These results confirm the effectiveness of the proposed model. 展开更多
关键词 Knowledge graph MULTI-MODAL entity alignment feature fusion pre-synergistic fusion
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An amphiphilic peptide with unnatural amino acids as an alignment medium for RDC measurements
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作者 Yishen Wang Haizhi Yin +3 位作者 Yanling Yang Zheng-Hui Li Gao-Wei Li Xinxiang Lei 《Magnetic Resonance Letters》 2025年第2期30-37,共8页
The multiple oligopeptides have been regarded as promising alignment media due to their structural diverseness and tendency for self-assembly in solution.Herein,an assembled amphiphilic peptide alignment medium,i.e.,C... The multiple oligopeptides have been regarded as promising alignment media due to their structural diverseness and tendency for self-assembly in solution.Herein,an assembled amphiphilic peptide alignment medium,i.e.,C15eCONH-Phg-Phg-IIIKK-CONH2 with un-natural amino acids for the determination of anisotropic parameters of NMR is introduced.The amphiphilic peptide can be self-assembled at low concentrations in DMSO and is stable and highly homogeneous.The NMR spectrum collected with the addition of the medium had fewer background signals.The utility of the acquired RDC data is demon-strated to determine relative configuration of three natural products,Helminthosporic acid,Estrone,and a-Santonin. 展开更多
关键词 Amphiphilic peptide alignment medium Residual dipolar coupling Liquid crystals Structural determination
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Self-FAGCFN:Graph-Convolution Fusion Network Based on Feature Fusion and Self-Supervised Feature Alignment for Pneumonia and Tuberculosis Diagnosis
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作者 Junding Sun Wenhao Tang +5 位作者 Lei Zhao Chaosheng Tang Xiaosheng Wu Zhaozhao Xu Bin Pu Yudong Zhang 《Journal of Bionic Engineering》 2025年第4期2012-2029,共18页
Feature fusion is an important technique in medical image classification that can improve diagnostic accuracy by integrating complementary information from multiple sources.Recently,Deep Learning(DL)has been widely us... Feature fusion is an important technique in medical image classification that can improve diagnostic accuracy by integrating complementary information from multiple sources.Recently,Deep Learning(DL)has been widely used in pulmonary disease diagnosis,such as pneumonia and tuberculosis.However,traditional feature fusion methods often suffer from feature disparity,information loss,redundancy,and increased complexity,hindering the further extension of DL algorithms.To solve this problem,we propose a Graph-Convolution Fusion Network with Self-Supervised Feature Alignment(Self-FAGCFN)to address the limitations of traditional feature fusion methods in deep learning-based medical image classification for respiratory diseases such as pneumonia and tuberculosis.The network integrates Convolutional Neural Networks(CNNs)for robust feature extraction from two-dimensional grid structures and Graph Convolutional Networks(GCNs)within a Graph Neural Network branch to capture features based on graph structure,focusing on significant node representations.Additionally,an Attention-Embedding Ensemble Block is included to capture critical features from GCN outputs.To ensure effective feature alignment between pre-and post-fusion stages,we introduce a feature alignment loss that minimizes disparities.Moreover,to address the limitations of proposed methods,such as inappropriate centroid discrepancies during feature alignment and class imbalance in the dataset,we develop a Feature-Centroid Fusion(FCF)strategy and a Multi-Level Feature-Centroid Update(MLFCU)algorithm,respectively.Extensive experiments on public datasets LungVision and Chest-Xray demonstrate that the Self-FAGCFN model significantly outperforms existing methods in diagnosing pneumonia and tuberculosis,highlighting its potential for practical medical applications. 展开更多
关键词 Feature fusion Self-supervised feature alignment Convolutional neural networks Graph convolutional networks Class imbalance Feature-centroid fusion
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UniTrans:Unified Parameter-Efficient Transfer Learning and Multimodal Alignment for Large Multimodal Foundation Model
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作者 Jiakang Sun Ke Chen +3 位作者 Xinyang He Xu Liu Ke Li Cheng Peng 《Computers, Materials & Continua》 2025年第4期219-238,共20页
With the advancements in parameter-efficient transfer learning techniques,it has become feasible to leverage large pre-trained language models for downstream tasks under low-cost and low-resource conditions.However,ap... With the advancements in parameter-efficient transfer learning techniques,it has become feasible to leverage large pre-trained language models for downstream tasks under low-cost and low-resource conditions.However,applying this technique to multimodal knowledge transfer introduces a significant challenge:ensuring alignment across modalities while minimizing the number of additional parameters required for downstream task adaptation.This paper introduces UniTrans,a framework aimed at facilitating efficient knowledge transfer across multiple modalities.UniTrans leverages Vector-based Cross-modal Random Matrix Adaptation to enable fine-tuning with minimal parameter overhead.To further enhance modality alignment,we introduce two key components:the Multimodal Consistency Alignment Module and the Query-Augmentation Side Network,specifically optimized for scenarios with extremely limited trainable parameters.Extensive evaluations on various cross-modal downstream tasks demonstrate that our approach surpasses state-of-the-art methods while using just 5%of their trainable parameters.Additionally,it achieves superior performance compared to fully fine-tuned models on certain benchmarks. 展开更多
关键词 Parameter-efficient transfer learning multimodal alignment image captioning image-text retrieval visual question answering
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Band alignment of heterojunctions formed by PtSe_(2)with doped GaN
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作者 Zhuoyang Lv Guijuan Zhao +2 位作者 Wanting Wei Xiurui Lv Guipeng Liu 《Chinese Physics B》 2025年第4期535-542,共8页
In order to investigate the effect of different doping types on the band alignment of heterojunctions,we prepared PtSe_(2)/n-GaN,PtSe_(2)/p-GaN,and PtSe_(2)/u-GaN heterojunctions by wet transfer technique.The valence ... In order to investigate the effect of different doping types on the band alignment of heterojunctions,we prepared PtSe_(2)/n-GaN,PtSe_(2)/p-GaN,and PtSe_(2)/u-GaN heterojunctions by wet transfer technique.The valence band offsets(VBO)of the three heterojunctions were measured by x-ray photoelectron spectroscopy(XPS),while the PtSe_(2)/n-GaN is 3.70±0.15 eV,PtSe_(2)/p-GaN is 0.264±0.15 eV,and PtSe_(2)/u-GaN is 3.02±0.15 eV.The conduction band offset(CBO)of the three heterojunctions was calculated from the material bandgap and VBO,while the PtSe_(2)/n-GaN is 0.61±0.15 eV,PtSe_(2)/p-GaN is 2.83±0.15 eV,and PtSe_(2)/u-GaN is 0.07±0.15 eV.This signifies that both PtSe_(2)/u-GaN and PtSe_(2)/p-GaN exhibit type-Ⅰband alignment,but the PtSe_(2)/n-GaN heterojunction has type-Ⅲband alignment.This signifies that the band engineering of PtSe_(2)/GaN heterojunction can be achieved by manipulating the concentration and type of doping,which is significantly relevant for the advancement of related devices through the realization of band alignment and the modulation of the material properties of the PtSe_(2)/GaN heterojunction. 展开更多
关键词 van der Waals heterojunction x-ray photoelectron spectroscopy band alignment gallium nitride platinum diselenide
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Impact of “Seven Planets in Alignment” on Global Climate Change
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作者 Cuixiang Zhong 《Journal of Environmental Science and Engineering(A)》 2025年第4期187-191,共5页
Just a few days after the astronomical spectacle of the“seven planets in alignment”on February 28,2025,the weather in many places underwent a dramatic change.In Shanghai,which was still at the beginning of spring(Ma... Just a few days after the astronomical spectacle of the“seven planets in alignment”on February 28,2025,the weather in many places underwent a dramatic change.In Shanghai,which was still at the beginning of spring(March 1),the temperature suddenly soared to 29℃,the temperature of summer,while Shandong was hit by a sudden heavy snowstorm.There are various opinions and no consensus on this inexplicable weather change.For this reason,based on the principle of the role of planets in the luminescence and heat generation of stars,the author of this article reveals the significant impact of the“Seven planets in alignment”on global climate change,and also points out that the melting of polar glaciers and the approach of the moon to the Earth is another important cause of global climate change.Therefore,countermeasures to save the abnormal changes in global climate are proposed. 展开更多
关键词 Seven planets in alignment glaciers melting global climate change COUNTERMEASURES
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Lamellar COF solid-state electrolytes for robust ambient-temperature lithium-ion transfer enhanced by PEI-driven channel alignment
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作者 Yafang Zhang Xinji Zhang +5 位作者 Jiajia Huang Zhirong Yang Shiyue Zhou Chenye Wang Wenjia Wu Jingtao Wang 《Green Energy & Environment》 2025年第5期982-993,共12页
Ionic covalent organic framework(COF)lamellar membranes are the alternative materials as promising Li^(+)conductors for all-solid-state lithium batteries.However,COF lamellar membrane suffers from poor structural stab... Ionic covalent organic framework(COF)lamellar membranes are the alternative materials as promising Li^(+)conductors for all-solid-state lithium batteries.However,COF lamellar membrane suffers from poor structural stability and inevitable cross-layer transfer resistance due to the weak interaction at interface of adjacent nanosheets.Herein,a lamellar polymer-threaded ionic COF(PEI@TpPa-SO_(3)Li)composite electrolyte with single Li^(+)conduction was prepared by assembling lithium sulfonated COF(TpPa-SO_(3)Li)nanosheets and then threading them with polyethyleneimine(PEI)chains.It reveals that the threaded PEI chains induce the oriented permutation of pore channel of PEI@TpPa-SO_(3)Li electrolyte through electrostatic interaction between-NH_(2)/-NH-and-SO_(3)Li groups.This enables the construction of continuous and aligned-SO_(3)^(-)...Li^(+)...-NH_(2)/-NH-pairs along pore channels,which act as efficient Li^(+)conducting sites and afford high Li^(+)hopping conduction(1.4×10^(-4)S cm^(-1)at 30℃)with a high Young's modulus of 408.7 MP and wide electrochemical stability window of 0~4.7 V.The assembled LiFePO_(4)‖Li and LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)‖Li half-cells achieve high discharge capacities of 155.0 mAh g^(-1)and 167.2 mAh g^(-1)at 30℃under0.2 C,respectively,with high capacity retention of 98%after 300 cycles.This study provides an alternative route to highly ion-conductive lamellar porous electrolytes for high-performance energy devices. 展开更多
关键词 Lamellar composite electrolyte COF nanosheets Polymer-driven channel alignment Ionic conductivity All-solid-state lithium battery
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Chasing in virtual environment:Dynamic alignment for multi-user collaborative redirected walking
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作者 Tianyang DONG Shuqian LV +1 位作者 Hubin KONG Huanbo ZHANG 《虚拟现实与智能硬件(中英文)》 2025年第1期26-46,共21页
Background The redirected walking(RDW)method for multi-user collaboration requires maintaining the relative position between users in a virtual environment(VE)and physical environment(PE).A chasing game in a VE is a t... Background The redirected walking(RDW)method for multi-user collaboration requires maintaining the relative position between users in a virtual environment(VE)and physical environment(PE).A chasing game in a VE is a typical virtual reality game that entails multi-user collaboration.When a user approaches and interacts with a target user in the VE,the user is expected to approach and interact with the target user in the corresponding PE as well.Existing methods of multi-user RDW mainly focus on obstacle avoidance,which does not account for the relative positional relationship between the users in both VE and PE.Methods To enhance the user experience and facilitate potential interaction,this paper presents a novel dynamic alignment algorithm for multi-user collaborative redirected walking(DA-RDW)in a shared PE where the target user and other users are moving.This algorithm adopts improved artificial potential fields,where the repulsive force is a function of the relative position and velocity of the user with respect to dynamic obstacles.For the best alignment,this algorithm sets the alignment-guidance force in several cases and then converts it into a constrained optimization problem to obtain the optimal direction.Moreover,this algorithm introduces a potential interaction object selection strategy for a dynamically uncertain environment to speed up the subsequent alignment.To balance obstacle avoidance and alignment,this algorithm uses the dynamic weightings of the virtual and physical distances between users and the target to determine the resultant force vector.Results The efficacy of the proposed method was evaluated using a series of simulations and live-user experiments.The experimental results demonstrate that our novel dynamic alignment method for multi-user collaborative redirected walking can reduce the distance error in both VE and PE to improve alignment with fewer collisions. 展开更多
关键词 Virtual reality Multi-user redirected walking User collisions Dynamic alignment
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