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Fine-tuning a large language model for automating computational fluid dynamics simulations
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作者 Zhehao Dong Zhen Lu Yue Yang 《Theoretical & Applied Mechanics Letters》 2025年第3期219-225,共7页
Configuring computational fluid dynamics(CFD)simulations typically demands extensive domain expertise,limiting broader access.Although large language models(LLMs)have advanced scientific computing,their use in automat... Configuring computational fluid dynamics(CFD)simulations typically demands extensive domain expertise,limiting broader access.Although large language models(LLMs)have advanced scientific computing,their use in automating CFD workflows is underdeveloped.We introduce a novel approach centered on domain-specific LLM adaptation.By fine-tuning Qwen2.5-7B-Instruct on NL2FOAM,our custom dataset of 28,716 natural language-to-OpenFOAM configuration pairs with chain-of-thought(CoT)annotations enables direct translation from natural language descriptions to executable CFD setups.A multi-agent system orchestrates the process,autonomously verifying inputs,generating configurations,running simulations,and correcting errors.Evaluation on a benchmark of 21 diverse flow cases demonstrates state-of-the-art performance,achieving 88.7%solution accuracy and 82.6%first-attempt success rate.This significantly outperforms larger general-purpose models such as Qwen2.5-72B-Instruct,DeepSeek-R1,and Llama3.3-70B-Instruct,while also requiring fewer correction iterations and maintaining high computational efficiency.The results highlight the critical role of domain-specific adaptation in deploying LLM assistants for complex engineering workflows.Our code and fine-tuned model have been deposited at https://github.com/YYgroup/AutoCFD. 展开更多
关键词 Large language models Fine-tuning Computational fluid dynamics Automated CFD Multi-agent system
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Evaluations of large language models in computational fluid dynamics:Leveraging,learning and creating knowledge
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作者 Long Wang Lei Zhang Guowei He 《Theoretical & Applied Mechanics Letters》 2025年第3期207-218,共12页
This paper investigates the capabilities of large language models(LLMs)to leverage,learn and create knowledge in solving computational fluid dynamics(CFD)problems through three categories of baseline problems.These ca... This paper investigates the capabilities of large language models(LLMs)to leverage,learn and create knowledge in solving computational fluid dynamics(CFD)problems through three categories of baseline problems.These categories include(1)conventional CFD problems that can be solved using existing numerical methods in LLMs,such as lid-driven cavity flow and the Sod shock tube problem;(2)problems that require new numerical methods beyond those available in LLMs,such as the recently developed Chien-physics-informed neural networks for singularly perturbed convection-diffusion equations;and(3)problems that cannot be solved using existing numerical methods in LLMs,such as the ill-conditioned Hilbert linear algebraic systems.The evaluations indicate that reasoning LLMs overall outperform non-reasoning models in four test cases.Reasoning LLMs show excellent performance for CFD problems according to the tailored prompts,but their current capability in autonomous knowledge exploration and creation needs to be enhanced. 展开更多
关键词 Large language models Computational fluid dynamics Machine learning
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Science Letters:Dynamic concision for three-dimensional reconstruction of human organ built with virtual reality modelling language (VRML) 被引量:3
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作者 禹正杨 郑树森 +2 位作者 陈雷霆 何晓乾 王建军 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第7期611-616,共6页
This research studies the process of 3D reconstruction and dynamic concision based on 2D medical digital images using virtual reality modelling language (VRML) and JavaScript language, with a focus on how to realize t... This research studies the process of 3D reconstruction and dynamic concision based on 2D medical digital images using virtual reality modelling language (VRML) and JavaScript language, with a focus on how to realize the dynamic concision of 3D medical model with script node and sensor node in VRML. The 3D reconstruction and concision of body internal organs can be built with such high quality that they are better than those obtained from the traditional methods. With the function of dynamic concision, the VRML browser can offer better windows for man-computer interaction in real-time environment than ever before. 3D reconstruction and dynamic concision with VRML can be used to meet the requirement for the medical observation of 3D reconstruction and have a promising prospect in the fields of medical imaging. 展开更多
关键词 Virtual Reality modelling language (VRML) Direct texture mapping Three-dimensional reconstruction dynamic concision
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A Knowledge Push Method of Complex Product Assembly Process Design Based on Distillation Model-Based Dynamically Enhanced Graph and Bayesian Network
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作者 Fengque Pei Yaojie Lin +2 位作者 Jianhua Liu Cunbo Zhuang Sikuan Zhai 《Chinese Journal of Mechanical Engineering》 2025年第6期117-134,共18页
Under the paradigm of Industry 5.0,intelligent manufacturing transcends mere efficiency enhancement by emphasizing human-machine collaboration,where human expertise plays a central role in assembly processes.Despite a... Under the paradigm of Industry 5.0,intelligent manufacturing transcends mere efficiency enhancement by emphasizing human-machine collaboration,where human expertise plays a central role in assembly processes.Despite advancements in intelligent and digital technologies,assembly process design still heavily relies on manual knowledge reuse,and inefficiencies and inconsistent quality in process documentation are caused.To address the aforementioned issues,this paper proposes a knowledge push method of complex product assembly process design based on distillation model-based dynamically enhanced graph and Bayesian network.First,an initial knowledge graph is constructed using a BERT-BiLSTM-CRF model trained with integrated human expertise and a fine-tuned large language model.Then,a confidence-based dynamic weighted fusion strategy is employed to achieve dynamic incremental construction of the knowledge graph with low resource consumption.Subsequently,a Bayesian network model is constructed based on the relationships between assembly components,assembly features,and operations.Bayesian network reasoning is used to push assembly process knowledge under different design requirements.Finally,the feasibility of the Bayesian network construction method and the effectiveness of Bayesian network reasoning are verified through a specific example,significantly improving the utilization of assembly process knowledge and the efficiency of assembly process design. 展开更多
关键词 Complex product assembly process Large language model dynamic incremental construction of knowledge graph Bayesian network Knowledge push
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Video action recognition meets vision-language models exploring human factors in scene interaction: a review
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作者 GUO Yuping GAO Hongwei +3 位作者 YU Jiahui GE Jinchao HAN Meng JU Zhaojie 《Optoelectronics Letters》 2025年第10期626-640,共15页
Video action recognition(VAR)aims to analyze dynamic behaviors in videos and achieve semantic understanding.VAR faces challenges such as temporal dynamics,action-scene coupling,and the complexity of human interactions... Video action recognition(VAR)aims to analyze dynamic behaviors in videos and achieve semantic understanding.VAR faces challenges such as temporal dynamics,action-scene coupling,and the complexity of human interactions.Existing methods can be categorized into motion-level,event-level,and story-level ones based on spatiotemporal granularity.However,single-modal approaches struggle to capture complex behavioral semantics and human factors.Therefore,in recent years,vision-language models(VLMs)have been introduced into this field,providing new research perspectives for VAR.In this paper,we systematically review spatiotemporal hierarchical methods in VAR and explore how the introduction of large models has advanced the field.Additionally,we propose the concept of“Factor”to identify and integrate key information from both visual and textual modalities,enhancing multimodal alignment.We also summarize various multimodal alignment methods and provide in-depth analysis and insights into future research directions. 展开更多
关键词 human factors video action recognition vision language models analyze dynamic behaviors spatiotemporal granularity video action recognition var aims multimodal alignment scene interaction
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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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Malware of Dynamic Behavior and Attack Patterns Using ATT&CK Framework
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作者 Jong-Yih Kuo Ping-Feng Wang +1 位作者 Ti-Feng Hsieh Cheng-Hsuan Kuo 《Computer Modeling in Engineering & Sciences》 2025年第6期3133-3166,共34页
In recent years,cyber threats have escalated across diverse sectors,with cybercrime syndicates increasingly exploiting system vulnerabilities.Traditional passive defense mechanisms have proven insufficient,particularl... In recent years,cyber threats have escalated across diverse sectors,with cybercrime syndicates increasingly exploiting system vulnerabilities.Traditional passive defense mechanisms have proven insufficient,particularly as Linux platforms—historically overlooked in favor of Windows—have emerged as frequent targets.According to Trend Micro,there has been a substantial increase in Linux-targeted malware,with ransomware attacks on Linux surpassing those on macOS.This alarming trend underscores the need for detection strategies specifically designed for Linux environments.To address this challenge,this study proposes a comprehensive malware detection framework tailored for Linux systems,integrating dynamic behavioral analysis with the semantic reasoning capabilities of large language models(LLMs).Malware samples are executed within sandbox environments to extract behavioral features such as system calls and command-line executions.These features are then systematically mapped to the MITRE ATT&CK framework,incorporating its defined data sources,data components,and Tactics,Techniques,and Procedures(TTPs).Two mapping constructs—Conceptual Definition Mapping and TTP Technical Keyword Mapping—are developed from official MITRE documentation.These resources are utilized to fine-tune an LLM,enabling it to semantically interpret complex behavioral patterns and infer associated attack techniques,including those employed by previously unknown malware variants.The resulting detection pipeline effectively bridges raw behavioral data with structured threat intelligence.Experimental evaluations confirm the efficacy of the proposed system,with the fine-tuned Gemma 2B model demonstrating significantly enhanced accuracy in associating behavioral features with ATT&CK-defined techniques.This study contributes a fully integrated Linux-specific detection framework,a novel approach for transforming unstructured behavioral data into actionable intelligence,improved interpretability of malicious behavior,and a scalable training process for future applications of LLMs in cybersecurity. 展开更多
关键词 Linux malware dynamic analysis behavior analysis behavioral feature ATT&CK SANDBOX large language model fine-tuning
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Artificial Intelligence-Based Sentiment Analysis of Dynamic Message Signs that Report Fatality Numbers Using Connected Vehicle Data
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作者 Dorcas O. Okaidjah Jonathan Wood Christopher M. Day 《Journal of Transportation Technologies》 2024年第4期590-606,共17页
This study presents results from sentiment analysis of Dynamic message sign (DMS) message content, focusing on messages that include numbers of road fatalities. As a traffic management tool, DMS plays a role in influe... This study presents results from sentiment analysis of Dynamic message sign (DMS) message content, focusing on messages that include numbers of road fatalities. As a traffic management tool, DMS plays a role in influencing driver behavior and assisting transportation agencies in achieving safe and efficient traffic movement. However, the psychological and behavioral effects of displaying fatality numbers on DMS remain poorly understood;hence, it is important to know the potential impacts of displaying such messages. The Iowa Department of Transportation displays the number of fatalities on a first screen, followed by a supplemental message hoping to promote safe driving;an example is “19 TRAFFIC DEATHS THIS YEAR IF YOU HAVE A SUPER BOWL DON’T DRIVE HIGH.” We employ natural language processing to decode the sentiment and undertone of the supplementary message and investigate how they influence driving speeds. According to the results of a mixed effect model, drivers reduced speeds marginally upon encountering DMS fatality text with a positive sentiment with a neutral undertone. This category had the largest associated amount of speed reduction, while messages with negative sentiment with a negative undertone had the second largest amount of speed reduction, greater than other combinations, including positive sentiment with a positive undertone. 展开更多
关键词 Intelligent Transportation System Sentiment Analysis dynamic Message Signs Large language models Traffic Safety Artificial Intelligence
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基于Modelica的吸收式热泵动态建模仿真
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作者 褚天宇 李慧 +1 位作者 郭美麟 段晓哲 《节能技术》 2025年第6期568-575,共8页
为研究R134a-DMF吸收式热泵机组的动态特性,本文在Mworks平台开发了一套R134a-DMF吸收式热泵模型库,并基于Modelica语言建立吸收式热泵的动态模型。热泵模型库主要包括介质模型、热泵部件模型和接口模型等。对所建模型进行仿真研究,得... 为研究R134a-DMF吸收式热泵机组的动态特性,本文在Mworks平台开发了一套R134a-DMF吸收式热泵模型库,并基于Modelica语言建立吸收式热泵的动态模型。热泵模型库主要包括介质模型、热泵部件模型和接口模型等。对所建模型进行仿真研究,得到热泵模型各模块关键参数及机组性能系数(COP)的动态特性。结果表明:所建立的热泵机组模型能够较好地反映热泵机组性能的动态特性,与文献参考值变化趋势保持一致,与文献参考值的误差在0.89%~2.08%之间。本文验证所开发模型库具有良好的准确性,可为后续R134a-DMF吸收式热泵实验运行及控制优化提供理论参考和技术支持。 展开更多
关键词 热泵机组 数学模型 modelICA语言 动态仿真 R134a-DMF
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EdEval:面向大语言模型评估中数据污染问题的动态解决方法
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作者 仲宝才 杨帆 《计算机工程与应用》 北大核心 2026年第6期214-224,共11页
随着大型语言模型(LLMs)在超大规模语料库上开展预训练,数据污染问题逐渐凸显,这对模型性能评估的准确性构成了直接威胁。提出了一种创新的动态数据评估方法EdEval(equal distribution dynamic evaluation),旨在降低数据污染对评估准确... 随着大型语言模型(LLMs)在超大规模语料库上开展预训练,数据污染问题逐渐凸显,这对模型性能评估的准确性构成了直接威胁。提出了一种创新的动态数据评估方法EdEval(equal distribution dynamic evaluation),旨在降低数据污染对评估准确性的影响。EdEval通过提取核心知识点与主旨,确保生成的评估问题在本质上与静态数据一致,并结合联网检索对知识点进行深入阐述,生成具有高质量知识支撑的评估样本。此外,EdEval通过控制问题数量和复杂度,实现动态对齐与灵活调节,以匹配静态数据的难度水平并满足不同复杂度的需求。采用布鲁姆分类法,EdEval从记忆、理解、应用、分析、评价和创造六个维度对LLMs进行综合评估。实验结果表明,EdEval在多个数据集上有效减轻了数据污染的影响,显著提高了评估的公正性和准确性。 展开更多
关键词 大语言模型 数据污染 动态数据评估 布鲁姆分类法
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基于语料库与预训练模型的非遗实体识别
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作者 张新生 杨颖洁 《计算机工程与设计》 北大核心 2026年第1期286-293,共8页
针对非遗领域文本语料稀缺,且非遗文本具有复杂语义特征导致命名实体识别精度不高的问题进行研究。构建非遗文本语料库ICHSX-NER,其实体字符串一致性和类型一致性分别为0.9530、0.9758。提出一种RBL-CFER实体识别模型,使用RoBERTa-wwm-... 针对非遗领域文本语料稀缺,且非遗文本具有复杂语义特征导致命名实体识别精度不高的问题进行研究。构建非遗文本语料库ICHSX-NER,其实体字符串一致性和类型一致性分别为0.9530、0.9758。提出一种RBL-CFER实体识别模型,使用RoBERTa-wwm-ext预训练语言模型提取高精度的词嵌入向量,借助BiLSTM提取非遗文本特征,CRF完成实体标签序列预测,实现对非遗文本语料中实体及其类别的识别。在自建语料库ICHSX-NER上进行多组实验,实验结果表明:模型的macro-F1值达90.62%,验证了在非遗文本实体识别任务中的有效性。 展开更多
关键词 命名实体识别 预训练语言模型 非遗文本语料库 动态全词掩码策略 双向长短期记忆网络 条件随机场 深度学习
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多体动力学模型的Modelica语言建模 被引量:3
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作者 刘俊 黄运保 +1 位作者 陈立平 王启富 《中国机械工程》 EI CAS CSCD 北大核心 2010年第9期1088-1093,共6页
对Adams多体模型结构及Modelica模型的转换方法进行了研究。对多体动力学模型结构及建模方式进行分析,根据Adams多体模型结构设计了对应的Modelica多体模型结构。研究了Adams多体模型各组件包含的信息,以及与Modelica模型的异同,提出了... 对Adams多体模型结构及Modelica模型的转换方法进行了研究。对多体动力学模型结构及建模方式进行分析,根据Adams多体模型结构设计了对应的Modelica多体模型结构。研究了Adams多体模型各组件包含的信息,以及与Modelica模型的异同,提出了各多体组件的转换方法。最后给出了多体模型转换验证实例与结果。该研究有助于提高多领域仿真系统的多体建模效率及与传统多体系统的兼容性。 展开更多
关键词 多领域统一建模 modelICA语言 多体动力学模型 模型转换
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基于大模型与时序知识增强的天然气用气量短期预测方法
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作者 赵周丙 吴冕 +4 位作者 吴柯莹 虞维超 宋尚飞 史博会 宫敬 《油气储运》 北大核心 2026年第1期109-119,共11页
【目的】随着中国天然气管网智能化发展水平的不断提高,天然气用气量的精准预测已成为管网优化调度的关键。当前预测方法存在对复杂多维因素过度依赖、覆盖用户范围受限以及时序知识集成能力缺乏等局限性,大语言模型(简称大模型)技术的... 【目的】随着中国天然气管网智能化发展水平的不断提高,天然气用气量的精准预测已成为管网优化调度的关键。当前预测方法存在对复杂多维因素过度依赖、覆盖用户范围受限以及时序知识集成能力缺乏等局限性,大语言模型(简称大模型)技术的进步为解决上述问题提供了有效途径。然而,现有大模型对相关行业领域认知不足,进而导致预测结果准确度低,且针对天然气用气量预测的大模型适配研究尚未深入。【方法】提出一种基于大模型与时序知识增强的天然气用气量预测方法:首先,构建天然气用气量时间序列知识库(简称时序知识库),以提取具有区域性的气量数据特征,并在构建时融入动态时间规整与中心化思想的K-means聚类算法,以解决欧氏距离失效问题;其次,为使部分参数固定的预训练大模型更有效地理解输入序列,在提示词范式中注入了数据分解、时序知识库相似性检索片段及统计学等先验知识;最后,构建补丁重编程层以适配大模型的输入,通过多头交叉自注意力机制实现时序数据与文本模态的对齐。【结果】算例验证表明:①建立时序知识库检索机制与构建提示词范式,可有效提升天然气用气量预测的准确性,且较传统方法滞后性更小、强趋势与周期性拟合能力更强、预测精度更高,通过构建重编程补丁嵌入层,可有效提升大模型针对强波动性数据的拟合与预测能力;②新建方法在4种数据集上的预测精度显著优于其他模型,从衡量预测准确性的关键指标来看,均方根误差、平均绝对误差、对称平均绝对百分比误差、平均绝对百分比误差的平均值分别为23635.6、10915.1、1.9%、1.9%,模型的决定系数平均值为0.96,能够很好地拟合观测数据,验证了新建预测方法的泛化性;③在超长期负荷预测中,新建方法通过融入丰富的多模态领域先验知识,较其他模型预测精度最高,模型预测结果的均方根误差、平均绝对误差、对称平均绝对百分比误差、平均绝对百分比误差分别比其他模型平均降低13.62%、21.49%、22.21%、22.91%,新建方法的决定系数平均值为0.95。【结论】新建方法不仅优于现有天然气用气量生成式预测领域的基准方法,还为多模态智能决策系统的构建提供了新的技术路径,推动预测技术从单一场景向跨模态协同方向演进。 展开更多
关键词 天然气 用气量预测 动态时间规整 大语言模型 检索增强 提示学习 多模态对齐
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基于大语言模型和深度强化学习的柔性作业车间动态调度问题研究
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作者 王丽君 王成广 +2 位作者 李相阳 文笑雨 LU Zhongyu 《计算机集成制造系统》 北大核心 2026年第1期145-158,共14页
在制造业数字化转型进程中,柔性作业车间的动态调度因工件随机到达、订单变更等实时扰动而极具挑战,传统调度方法在应对动态插入工件时往往难以兼顾效率与适应性。针对工件动态插入的柔性作业车间动态调度问题,以最小化总延期时间为目标... 在制造业数字化转型进程中,柔性作业车间的动态调度因工件随机到达、订单变更等实时扰动而极具挑战,传统调度方法在应对动态插入工件时往往难以兼顾效率与适应性。针对工件动态插入的柔性作业车间动态调度问题,以最小化总延期时间为目标,提出一种将大语言模型(LLM)与深度强化学习(DRL)结合的LLM-DQN算法。通过将LLM的语义理解能力与深度Q网络(DQN)相结合,构建了包含状态空间优化、混合动作选择和奖励函数设计的集成框架。在状态表示方面,利用LLM生成加权特征向量以突出关键调度指标;在动作选择阶段,设计混合策略实现LLM专家建议与DQN策略的动态融合;同时引入LLM驱动的自适应奖励机制。在DeepSeek和Doubao等大语言模型上的仿真实验表明,LLM-DQN在多种测试场景下优于单一调度动作及其他深度强化学习方法。 展开更多
关键词 大语言模型 深度强化学习 柔性作业车间 动态调度
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大语言模型检查点机制研究综述
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作者 刘晓宇 曾令仿 《计算机工程与应用》 北大核心 2026年第3期57-72,共16页
随着大语言模型在自然语言处理领域的广泛应用,检查点机制作为提升训练效率、减少计算开销和增强容错能力的关键技术,受到了越来越多的关注。系统研究了大语言模型中的检查点机制及其优化方法,回顾了大语言模型的基本架构和发展历程,分... 随着大语言模型在自然语言处理领域的广泛应用,检查点机制作为提升训练效率、减少计算开销和增强容错能力的关键技术,受到了越来越多的关注。系统研究了大语言模型中的检查点机制及其优化方法,回顾了大语言模型的基本架构和发展历程,分析了传统检查点机制的应用,并探讨了其在大语言模型训练中的特殊需求和实现方式。通过对典型训练框架的调研,总结了它们在检查点机制实现和优化中的关键特点与技术挑战,并对现有优化方法进行了分类讨论,主要包括降低固定开销、动态检查点和降低恢复损失三大方向。进一步,展望了大语言模型检查点机制未来的发展趋势,提出了基于预测性检查点、新型存储介质优化、分布式计算提升恢复效率以及异构计算架构优化等潜在的研究方向,这些研究方向为提升大规模模型的训练效率和可扩展性提供了新的技术思路。 展开更多
关键词 大语言模型 检查点机制 优化技术 固定开销 动态检查点 恢复损失
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Protein language model empowered the robust ASR-driven PET hydrolase featured with two PET binding motifs
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作者 Yibo Song Anni Li +4 位作者 Haiyang Cui Bo Zhou Jie Qiao Junnan Wei Xiujuan Li 《Green Carbon》 2025年第4期419-428,共10页
Various tools specifically designed to accelerate evolutionary processes for biocatalysis and biotransformation have been developed in the field of protein engineering.Among them,protein language modeling(PLM)is extre... Various tools specifically designed to accelerate evolutionary processes for biocatalysis and biotransformation have been developed in the field of protein engineering.Among them,protein language modeling(PLM)is extremely efficient for large-scale screening,thus initiating a new era of accelerated prediction.Therefore,this study considered the highly promising ancestral sequence reconstruction 1(AsR1)-polyethylene terephthalate hydrolase(PETase),previously obtained via ancestral sequence reconstruction,as a representative model.The PLM Evolutionary Scale Modeling-1V was used as an amino acid optimizer to efficiently identify four beneficial variants that improved terephthalic acid(TPA)yield by 1.7-fold.The triple variant ASR1-HRT(N81H/W120R/V265T)showed a 6.1-fold increase in TPA yield compared with that of the five-site variant FAST-PETase(N233K/R224Q/S121E/D186H/R280A)through the recombination of a single beneficial variant.Moreover,ASR1-HRT achieved a depolymerization rate of 96.1%for commercial polyethylene terephthalate(PET)plastics.Molecular dynamics simulations showed that the enhancement of structural stability at high temperatures and changes in catalytic reactions due to solvation contributed to efficient and stable properties.In addition,through exploring the enzyme-PET film interaction landscape at the molecular level,the two motifs of ASR1-PETase were found to play key roles in the catalytic process at the solid-liquid interface.This enhanced the initial adsorption of the enzyme on PET film,thereby enhancing the hydrolysis performance.Overall,the PLM optimization strategy has the potential to be applied to other enzymes,thereby efficiently accelerating protein engineering. 展开更多
关键词 Film molecular dynamics simulation Protein language model Polyethylene terephthalate depolymerization Polyethylene terephthalate hydrolase Two polyethylene terephthalate binding motifs
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基于动态前缀提示及数据增强的情感四元组提取方法 被引量:2
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作者 钟将 刘雨轩 +3 位作者 戴启祝 王佳祺 赖心怡 胡雯月 《计算机学报》 北大核心 2025年第5期1082-1099,共18页
在方面级情感分析(Aspect-Based Sentiment Analysis, ABSA)中,情感四元组提取是一个能全面分析情感且最具挑战性的任务。当前基于生成式的方法存在两方面局限性:(1)依赖于提示设计,无法针对任务动态优化,导致提示次优的问题;(2)未能充... 在方面级情感分析(Aspect-Based Sentiment Analysis, ABSA)中,情感四元组提取是一个能全面分析情感且最具挑战性的任务。当前基于生成式的方法存在两方面局限性:(1)依赖于提示设计,无法针对任务动态优化,导致提示次优的问题;(2)未能充分解决隐含情感数据不平衡的问题,导致在处理这类数据时性能不佳。为解决这些问题,本文提出了一种动态前缀提示方法(Dynamic Prefix Prompt),该方法利用可调整的前缀和注意力机制来动态优化提示。此外,本文设计了一种基于大语言模型的数据增强策略,该策略通过微调的方式来对齐数据扩充任务以平衡隐含情感数据。在两个真实应用的数据集上的实验表明,本文所提出的方法在Restaurants-ACOS和Laptop-ACOS数据集上F1分数分别提升3.60和2.20,同时在隐含情感数据中F1分数平均提升了4.23和4.67,达到目前最先进的水平,验证了本文方法的有效性和优越性。 展开更多
关键词 方面级情感分析 情感四元组提取 动态前缀提示 隐含情感数据 大语言模型 数据增强
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基于动态关系原型的持续关系抽取技术
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作者 钟将 戴启祝 李雪 《电子学报》 北大核心 2025年第9期3287-3298,共12页
持续关系抽取(Continuous Relation Extraction,CRE)在理解和适应不断变化的数据环境中扮演着至关重要的角色.传统的CRE技术通常面临两大难题:一是关系模式的持续演变,二是遗忘之前学习的关系的风险.尽管存储和重放旧关系典型示例的做... 持续关系抽取(Continuous Relation Extraction,CRE)在理解和适应不断变化的数据环境中扮演着至关重要的角色.传统的CRE技术通常面临两大难题:一是关系模式的持续演变,二是遗忘之前学习的关系的风险.尽管存储和重放旧关系典型示例的做法在减少遗忘方面已被证明是有效的,但反复重放这些固定且有限的样本可能导致过拟合.为了解决这一问题,本文提出了一种基于动态原型的持续关系抽取方法.该方法结合了密度聚类和生成式大型语言模型,以应对上述挑战,本文将其命名为密度聚类和生成式大型语言建模(Continuous Relation Extraction with Density based Clustering and Generative Large Language Model,CRE-DCGLLM).具体而言,本文采用了密度聚类技术来提取记忆样本,缓解对先前任务的遗忘问题,并基于全量样本和记忆样本设计了动态关系原型.此外,本文通过生成式大语文模型为记忆样本生成伪样本用于重放训练,以解决因多次重放导致的模型过拟合问题.同时,本文还运用焦点知识蒸馏技术,以提升对变化中关系模式的适应性能.通过在FewRel数据集和TACRED数据集上进行的一系列实验,本文验证了该方法的有效性.实验结果显示,本文的方法在持续关系抽取的准确性和效率方面都取得了显著的提升,特别是在处理相似关系、防止知识遗忘以及克服过拟合等方面表现出了卓越的性能. 展开更多
关键词 持续关系抽取 聚类 大语言模型 密度峰值 动态原型
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面向卫星任务规划的专家链构建与优化方法
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作者 夏维 魏宏图 +2 位作者 程颖 汪君婷 胡笑旋 《电子与信息学报》 北大核心 2025年第12期4986-4994,共9页
卫星任务规划是航天资源调度领域的关键优化问题,在面对动态需求时,传统方法因其复杂的建模流程,常面临响应滞后、灵活性不足等挑战,且业务语言与数学模型间存在语义断层。为此,该文提出一种基于专家链(CoE)与动态知识增强机制(DKE)的... 卫星任务规划是航天资源调度领域的关键优化问题,在面对动态需求时,传统方法因其复杂的建模流程,常面临响应滞后、灵活性不足等挑战,且业务语言与数学模型间存在语义断层。为此,该文提出一种基于专家链(CoE)与动态知识增强机制(DKE)的大语言模型(LLM)推理框架。该框架聚焦于模型动态修改,通过设计一个需求解析、指令路由和代码生成的专家协同工作流,实现从自然语言指令到数学模型的精确映射。此外,该框架借助动态知识库与Few-Shot学习策略,使系统在不依赖梯度更新情况下具备持续优化能力。实验结果表明,相较于标准提示词方法(SP)、思维链技术(CoT)以及基于GPT4-o的标准提示词方法,准确率达到82%,平均响应时间81.28 s,显著优于所有对比基线,实验结果验证了该方法能够有效提升LLM在卫星任务规划模型动态修改任务中的处理能力。 展开更多
关键词 大语言模型 卫星任务规划 模型动态修改 专家链
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