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Electronic Structure Computations and Optical Spectroscopy Studies of ScNiBi and YNiBi Compounds
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作者 Yury V.Knyazev Semyon T.Baidak +1 位作者 Yury I.Kuz’min Alexey V.Lukoyanov 《Computers, Materials & Continua》 2025年第6期4085-4095,共11页
Thework presents the electronic structure computations and optical spectroscopy studies of half-Heusler ScNiBi and YNiBi compounds.Our first-principles computations of the electronic structures were based on density f... Thework presents the electronic structure computations and optical spectroscopy studies of half-Heusler ScNiBi and YNiBi compounds.Our first-principles computations of the electronic structures were based on density functional theory accounting for spin-orbit coupling.These compounds are computed to be semiconductors.The calculated gap values make ScNiBi and YNiBi valid for thermoelectric and optoelectronic applications and as selective filters.In ScNiBi and YNiBi,an intense peak at the energy of−2 eV is composed of theNi 3d states in the conduction band,and the valence band mostly contains these states with some contributions from the Bi 6p and Sc 3d or Y 4d electronic states.These states participate in the formation of the indirect gap of 0.16 eV(ScNiBi)and 0.18 eV(YNiBi).Within the spectral ellipsometry technique in the interval 0.22–15μm of wavelength,the optical functions of materials are studied,and their dispersion features are revealed.A good matching of the experimental and modeled optical conductivity spectra allowed us to analyze orbital contributions.The abnormally low optical absorption observed in the low-energy region of the spectrum is referred to as the results of band calculations indicating a small density of electronic states near the Fermi energy of these complex materials. 展开更多
关键词 Computational physics first-principles calculations electronic structure band gap excited states optical properties semiconductors complex materials optoelectronic applications
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基于子模块顺序移位的MMC电容电压平衡策略
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作者 马文忠 孙远博 +3 位作者 王玉生 张文艳 李恒硕 朱亚恒 《电力自动化设备》 北大核心 2026年第1期179-184,共6页
模块化多电平换流器(MMC)子模块(SM)电容电压平衡决定系统能否安全稳定运行。针对传统电压排序法运算量大的问题,提出一种无需电压排序的SM电容电压平衡策略。按照系统中SM位置顺序,为了输出期望波形投入相应数量SM,对SM进行充放电。为... 模块化多电平换流器(MMC)子模块(SM)电容电压平衡决定系统能否安全稳定运行。针对传统电压排序法运算量大的问题,提出一种无需电压排序的SM电容电压平衡策略。按照系统中SM位置顺序,为了输出期望波形投入相应数量SM,对SM进行充放电。为了实现SM电压平衡,根据SM电容电压状态,提出了SM顺序前移和后移2种移位策略,并根据电容电压差值与所设定阈值更换SM投切顺序。在MATLAB/Simulink平台和硬件在环系统中对所提策略进行验证。结果表明,所提策略复杂度低,运算量小,有效降低了SM的开关频率。 展开更多
关键词 MMC SM 电容电压平衡 运算复杂度 开关频率
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Generalization of Results of Computations and Natural Experiments at Steel Parts Quenching 被引量:2
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作者 Nikolai I.Kobasko Engineering Thermophysics Institute of National Academy of Sciences, Kyiv, Ukraine 《Journal of Shanghai Jiaotong university(Science)》 EI 2000年第1期128-134,共7页
Complicated changes occur inside the steel parts during quenching process. A three dimensional nonlinear mathematical model for quenching process has been established and the numerical simulation on temperature field,... Complicated changes occur inside the steel parts during quenching process. A three dimensional nonlinear mathematical model for quenching process has been established and the numerical simulation on temperature field, microstructure and stress field has been realized. The alternative technique for the formation of high-strength materials has been developed on the basis of intensification of heat transfer at phase transformations. The technology for the achievement of maximum compressive residual stresses on the hard surface is introduced. It has been shown that there is an optimal depth of hard layer providing the maximum compression stresses on the surface. It has also been established that in the surface hard layer additional strengthening (superstrengthening) of the material is observed. The generalized formula for the determination of the time of reaching maximum compressive stresses on the surface has been proposed. 展开更多
关键词 QUENCHING Phase Transformation Temperature FIELD Stress FIELD Maximum COMPRESSIVE Stresses Superstrengthening of Materials GENERALIZATION of RESULTS of computations.
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深度学习赋能的传统村落建筑风格识别与多尺度空间格局研究
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作者 韩青 尹超 杨玉 《热带地理》 北大核心 2026年第1期179-189,共11页
传统建筑是村落风貌的基石,也是地域气候、文化认同与集体记忆的直观物质载体。文章以中国646个首批传统村落为研究对象,构建了涵盖建筑立面、构件特征和文化符号的多模态图像数据库。聚焦京派、晋派、川派、皖派、苏派、闽派六大典型... 传统建筑是村落风貌的基石,也是地域气候、文化认同与集体记忆的直观物质载体。文章以中国646个首批传统村落为研究对象,构建了涵盖建筑立面、构件特征和文化符号的多模态图像数据库。聚焦京派、晋派、川派、皖派、苏派、闽派六大典型建筑流派,采用EfficientNet模型实现了高精度(90%)的单体建筑风格自动识别,并基于Grad-CAM技术完成不同建筑风格的关键建筑构件分析。文章进一步结合空间自相关分析与多样性指数,系统揭示了不同建筑风格在多尺度下的空间分布模式和跨流域文化交互特征。结果表明:1)6类建筑风格特征显著,模型识别效果良好,但京派与川派川派由于注意力均集中于木制房墙与廊柱,具有一定的交叉误判率;2)在宏观格局上,各建筑风格的影响范围与轴向分布存在差异,且其空间展布与地理廊道高度耦合,形成了显著的文化过渡带;3)在区域层面,建筑风格聚集区形成了5个文化核心区、3个文化过渡带与2个文化断裂带,为构建跨省遗产廊道保护体系提供了空间依据;4)在省域内部,建筑风格呈现“高多样-高均匀”“低多样-低均匀”“低多样-高均匀”3种模式,反映了不同省份文化整合与地方表达的差异格局。文章提出的智能解译-空间计算协同框架,为文化地理学研究提供了可扩展的方法论及工具,也为多尺度的传统村落保护、区域规划与文旅发展提供了坚实的科学依据与数据支撑。 展开更多
关键词 传统村落 建筑风格识别 深度学习 多尺度空间分异 文化地理计算
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社会互动对智慧景区游客环境责任行为的影响机制
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作者 罗文斌 李佳 《浙江大学学报(理学版)》 北大核心 2026年第1期109-118,共10页
在数字文旅时代,人机互动作为一种新型的社会关系正在影响和改变智慧景区游客的行为。以刺激-机体-反应(SOR)理论为框架,探析了“人机互动”与“人际互动”对游客环境责任行为的影响机制,构建了以难忘的旅游体验为中介变量、以游览频次... 在数字文旅时代,人机互动作为一种新型的社会关系正在影响和改变智慧景区游客的行为。以刺激-机体-反应(SOR)理论为框架,探析了“人机互动”与“人际互动”对游客环境责任行为的影响机制,构建了以难忘的旅游体验为中介变量、以游览频次为调节变量的解释框架。同时,基于湖南省长沙市岳麓山景区的514份有效调查问卷,运用结构方程模型进行实证分析。结果表明:(1)社会互动影响游客环境责任行为,其中“人机互动”对环境责任行为具有显著正向影响,而“人际互动”的影响不显著。(2)社会互动促进难忘的旅游体验的形成,且难忘的旅游体验在社会互动与游客环境责任行为之间起中介作用。(3)游览频次能调节社会互动对游客环境责任行为的影响。所得结果有助于厘清社会互动与游客环境责任行为之间的关系,并为智慧景区建设提供决策参考。 展开更多
关键词 人机互动 人际互动 游客环境责任行为 智慧景区
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基于人工智能的计算机教师信息素养提升研究
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作者 林凌 《计算机应用文摘》 2026年第1期1-3,共3页
在信息化教学背景下,计算机教师普遍存在信息素养结构不均衡、应用能力不足等短板,在一定程度上制约了教育信息化的深入发展。对此,文章提出一种依托信息化技术赋能的三阶段路径方法:首先基于德尔菲法构建教师信息素养综合评价体系,其... 在信息化教学背景下,计算机教师普遍存在信息素养结构不均衡、应用能力不足等短板,在一定程度上制约了教育信息化的深入发展。对此,文章提出一种依托信息化技术赋能的三阶段路径方法:首先基于德尔菲法构建教师信息素养综合评价体系,其次应用聚类算法实现教师群体的精准分层与针对性培训设计,最后借助卷积神经网络(CNN)对培训过程和效果进行动态评估,形成优化反馈机制。实验结果表明,该方法能够显著提升计算机教师的信息素养水平和教学适应能力。 展开更多
关键词 信息化技术 计算机教师 信息素养 提升路径
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Realistic Efficiency Evaluations for Parallel Computations under Workstation Cluster
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作者 Mo Zeyao Li Xiaomei(Dept. of Computer, Changsha institute of Technology Changsha, China, 410073) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第Z1期329-336,共8页
In recent years, high performance scientific computing under workstation cluster connected by local area network is becoming a hot point. Owing to both the longer latency and the higher overhead for protocol processin... In recent years, high performance scientific computing under workstation cluster connected by local area network is becoming a hot point. Owing to both the longer latency and the higher overhead for protocol processing compared with the powerful single workstation capacity, it is becoming severe important to keep balance not only for numerical load but also for communication load, and to overlap communications with computations while parallel computing. Hence,our efficiency evaluation rules must discover these capacities of a given parallel algorithm in order to optimize the existed algorithm to attain its highest parallel efficiency. The traditional efficiency evaluation rules can not succeed in this work any more. Fortunately, thanks to Culler's detail discuss in LogP model about interconnection networks for MPP systems, we present a system of efficiency evaluation rules for parallel computations under workstation cluster with PVM3.0 parallel software framework in this paper. These rules can satisfy above acquirements successfully. At last, two typical synchronous,and asynchronous applications are designed to verify the validity of these rules under 4 SGIs workstations cluster connected by Ethernet. 展开更多
关键词 parallel efficiency evaluation workstation cluster PVM. network parallel computations.
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Two-Dimensional MXene-Based Advanced Sensors for Neuromorphic Computing Intelligent Application
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作者 Lin Lu Bo Sun +2 位作者 Zheng Wang Jialin Meng Tianyu Wang 《Nano-Micro Letters》 2026年第2期664-691,共28页
As emerging two-dimensional(2D)materials,carbides and nitrides(MXenes)could be solid solutions or organized structures made up of multi-atomic layers.With remarkable and adjustable electrical,optical,mechanical,and el... As emerging two-dimensional(2D)materials,carbides and nitrides(MXenes)could be solid solutions or organized structures made up of multi-atomic layers.With remarkable and adjustable electrical,optical,mechanical,and electrochemical characteristics,MXenes have shown great potential in brain-inspired neuromorphic computing electronics,including neuromorphic gas sensors,pressure sensors and photodetectors.This paper provides a forward-looking review of the research progress regarding MXenes in the neuromorphic sensing domain and discussed the critical challenges that need to be resolved.Key bottlenecks such as insufficient long-term stability under environmental exposure,high costs,scalability limitations in large-scale production,and mechanical mismatch in wearable integration hinder their practical deployment.Furthermore,unresolved issues like interfacial compatibility in heterostructures and energy inefficiency in neu-romorphic signal conversion demand urgent attention.The review offers insights into future research directions enhance the fundamental understanding of MXene properties and promote further integration into neuromorphic computing applications through the convergence with various emerging technologies. 展开更多
关键词 TWO-DIMENSIONAL MXenes SENSOR Neuromorphic computing Multimodal intelligent system Wearable electronics
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High-Entropy Oxide Memristors for Neuromorphic Computing:From Material Engineering to Functional Integration
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作者 Jia‑Li Yang Xin‑Gui Tang +4 位作者 Xuan Gu Qi‑Jun Sun Zhen‑Hua Tang Wen‑Hua Li Yan-Ping Jiang 《Nano-Micro Letters》 2026年第2期138-169,共32页
High-entropy oxides(HEOs)have emerged as a promising class of memristive materials,characterized by entropy-stabilized crystal structures,multivalent cation coordination,and tunable defect landscapes.These intrinsic f... High-entropy oxides(HEOs)have emerged as a promising class of memristive materials,characterized by entropy-stabilized crystal structures,multivalent cation coordination,and tunable defect landscapes.These intrinsic features enable forming-free resistive switching,multilevel conductance modulation,and synaptic plasticity,making HEOs attractive for neuromorphic computing.This review outlines recent progress in HEO-based memristors across materials engineering,switching mechanisms,and synaptic emulation.Particular attention is given to vacancy migration,phase transitions,and valence-state dynamics—mechanisms that underlie the switching behaviors observed in both amorphous and crystalline systems.Their relevance to neuromorphic functions such as short-term plasticity and spike-timing-dependent learning is also examined.While encouraging results have been achieved at the device level,challenges remain in conductance precision,variability control,and scalable integration.Addressing these demands a concerted effort across materials design,interface optimization,and task-aware modeling.With such integration,HEO memristors offer a compelling pathway toward energy-efficient and adaptable brain-inspired electronics. 展开更多
关键词 High-entropy oxides MEMRISTORS Neuromorphic computing Configurational entropy Resistive switching
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Mechanical Properties Analysis of Flexible Memristors for Neuromorphic Computing
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作者 Zhenqian Zhu Jiheng Shui +1 位作者 Tianyu Wang Jialin Meng 《Nano-Micro Letters》 2026年第1期53-79,共27页
The advancement of flexible memristors has significantly promoted the development of wearable electronic for emerging neuromorphic computing applications.Inspired by in-memory computing architecture of human brain,fle... The advancement of flexible memristors has significantly promoted the development of wearable electronic for emerging neuromorphic computing applications.Inspired by in-memory computing architecture of human brain,flexible memristors exhibit great application potential in emulating artificial synapses for highefficiency and low power consumption neuromorphic computing.This paper provides comprehensive overview of flexible memristors from perspectives of development history,material system,device structure,mechanical deformation method,device performance analysis,stress simulation during deformation,and neuromorphic computing applications.The recent advances in flexible electronics are summarized,including single device,device array and integration.The challenges and future perspectives of flexible memristor for neuromorphic computing are discussed deeply,paving the way for constructing wearable smart electronics and applications in large-scale neuromorphic computing and high-order intelligent robotics. 展开更多
关键词 Flexible memristor Neuromorphic computing Mechanical property Wearable electronics
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Numerical Analysis and Geometric Assessment of Air Layer Distribution in a Ventilated Planing Hull in Calm Water
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作者 Massimiliano Chillemi Filippo Cucinotta Felice Sfravara 《哈尔滨工程大学学报(英文版)》 2026年第1期46-62,共17页
The issue of resistance reduction through hull ventilation is of particular interest in contemporary research.This paper presents multiphase computational fluid dynamics(CFD)simulations with 2-DOF motion of a planing ... The issue of resistance reduction through hull ventilation is of particular interest in contemporary research.This paper presents multiphase computational fluid dynamics(CFD)simulations with 2-DOF motion of a planing hull.The original hull was modified by introducing a step to allow air ventilation.Following an assessment of the hull performance,a simulation campaign in calm water was conducted to characterize the hull at various forward speeds and air insufflation rates for a defined single step geometry.Geometric analysis of the air layer thickness beneath the hull for each simulated condition was performed using a novel method for visualizing local air thickness.Additionally,two new parameters were introduced to understand the influence of spray rails on the air volume beneath the hull and to indicate the primary direction of ventilated air escape.A validation campaign and an assessment of uncertainty of the simulation has been conducted.The features offered by the CFD methodology include the evaluation of the air layer thickness as a function of hull velocity and injection flow rate and the air volume distribution beneath the hull.The air injection velocity can be adjusted across various operating conditions,thereby preventing performance or efficiency loss during navigation.Based on these findings,the study highlights the benefits of air insufflation in reducing hull resistance for high-speed planing vessels.This work lays a robust foundation for future research and new promising topics,as the exploration of air insufflation continues to be a topic of contemporary interest within naval architecture and hydrodynamics. 展开更多
关键词 Computational fluid dynamics Air cavity ships Planing hull HYDRODYNAMICS Maritime sustainability
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Combined multidetector computed tomography and gastrointestinal endoscopy for gastric cancer screening,preoperative staging,and lymph node metastasis detection
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作者 Le-Ping Ye Yan-Ping Zhang +4 位作者 Gang Chen Yi-Xian Wu Cheng-Long He Dong Wang Qiao Mei 《World Journal of Gastrointestinal Oncology》 2026年第1期200-210,共11页
BACKGROUND Early screening,preoperative staging,and diagnosis of lymph node metastasis are crucial for improving the prognosis of gastric cancer(GC).AIM To evaluate the diagnostic value of combined multidetector compu... BACKGROUND Early screening,preoperative staging,and diagnosis of lymph node metastasis are crucial for improving the prognosis of gastric cancer(GC).AIM To evaluate the diagnostic value of combined multidetector computed tomography(MDCT)and gastrointestinal endoscopy for GC screening,preoperative staging,and lymph node metastasis detection,thereby providing a reference for clinical diagnosis and treatment.METHODS In this retrospective study clinical and imaging data of 134 patients with suspected GC who were admitted between January 2023 and October 2024 were initially reviewed.According to the inclusion and exclusion criteria,102 patients were finally enrolled in the analysis.All enrolled patients had undergone both MDCT and gastrointestinal endoscopy examinations prior to surgical intervention.Preoperative clinical staging and lymph node metastasis findings were compared with pathological results.RESULTS The combined use of MDCT and gastrointestinal endoscopy demonstrated a sensitivity of 98.53%,specificity of 97.06%,accuracy of 98.04%,positive predictive value of 98.53%,and negative predictive value of 97.06%for diagnosing GC.These factors were all significantly higher than those of MDCT or endoscopy alone(P<0.05).The accuracy rates of the combined approach for detecting clinical T and N stages were 97.06%and 92.65%,respectively,outperforming MDCT alone(86.76% and 79.41%)and endoscopy alone(85.29% and 70.59%)(P<0.05).Among 68 patients with confirmed GC,50(73.53%)were pathologically diagnosed with lymph node metastasis.The accuracy for detecting lymph node metastasis was 66.00%with endoscopy,76.00%with MDCT,and 92.00% with the combined approach,all with statistically significant differences(P<0.05).CONCLUSION The combined application of MDCT and gastrointestinal endoscopy enhanced diagnostic accuracy for GC,provided greater consistency in preoperative staging,and improved the detection of lymph node metastasis,thereby demonstrating significant clinical utility. 展开更多
关键词 Multidetector computed tomography Gastrointestinal endoscopy Gastric cancer Preoperative staging Lymph node metastasis
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Future directions of image-guided thermal ablation in colorectal cancer lung oligometastases
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作者 Yu-Yin Wang Cui-Ping Zhang +3 位作者 Qing-Biao Zhang Xing-Yan Le Jun-Bang Feng Chuan-Ming Li 《World Journal of Gastroenterology》 2026年第2期162-166,共5页
Colorectal cancer(CRC)with lung oligometastases,particularly in the presence of extrapulmonary disease,poses considerable therapeutic challenges in clinical practice.We have carefully studied the multicenter study by ... Colorectal cancer(CRC)with lung oligometastases,particularly in the presence of extrapulmonary disease,poses considerable therapeutic challenges in clinical practice.We have carefully studied the multicenter study by Hu et al,which evaluated the survival outcomes of patients with metastatic CRC who received image-guided thermal ablation(IGTA).These findings provide valuable clinical evidence supporting IGTA as a feasible,minimally invasive approach and underscore the prognostic significance of metastatic distribution.However,the study by Hu et al has several limitations,including that not all pulmonary lesions were pathologically confirmed,postoperative follow-up mainly relied on dynamic contrast-enhanced computed tomography,no comparative analysis was performed with other local treatments,and the impact of other imaging features on efficacy and prognosis was not evaluated.Future studies should include complete pathological confirmation,integrate functional imaging and radiomics,and use prospective multicenter collaboration to optimize patient selection standards for IGTA treatment,strengthen its clinical evidence base,and ultimately promote individualized decision-making for patients with metastatic CRC. 展开更多
关键词 Colorectal cancer Lung oligometastases Extrapulmonary metastases Imageguided thermal ablation Dynamic contrast-enhanced computed tomography Functional imaging
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人体动作姿态识别方法研究综述
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作者 梁本来 《信息记录材料》 2026年第1期18-20,26,共4页
人体动作识别技术是计算机视觉领域的重要研究方向。本文综述了当前主流的人体动作姿态识别方法,包括基于图像的姿态估计、基于视频的时序分析、三维空间姿态重建及基于骨架的动作识别等方法,通过对比分析各类方法在计算复杂度、场景适... 人体动作识别技术是计算机视觉领域的重要研究方向。本文综述了当前主流的人体动作姿态识别方法,包括基于图像的姿态估计、基于视频的时序分析、三维空间姿态重建及基于骨架的动作识别等方法,通过对比分析各类方法在计算复杂度、场景适应性和性能表现(准确性、实时性、鲁棒性等)等方面的特点,揭示了该技术领域面临的三维标注数据获取困难、复杂环境泛化能力不足及实时性与精度难以兼顾等核心挑战。针对未来发展趋势,本文探讨了轻量化模型设计、多模态融合、弱监督与自监督学习、三维时空建模、Transformer架构应用及领域自适应等关键研究方向,旨在为后续相关研究提供思路与借鉴。 展开更多
关键词 人体动作姿态识别 深度学习 计算机视觉 时空图卷积网络
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CompuDEX:基于区块链的大模型微调算力共享平台
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作者 张凌浩 谭海波 +3 位作者 赵赫 陈中 程昊天 马志宇 《浙江大学学报(工学版)》 北大核心 2026年第1期1-18,共18页
利用分布在世界各地的闲置算力对大语言模型进行训练,有望提供全新的算力供应模式和削减训练成本.针对此方法存在的隐私风险、恶意攻击和信任缺失问题,提出基于区块链的大模型微调算力共享平台CompuDEX.充分利用区块链技术去信任、匿名... 利用分布在世界各地的闲置算力对大语言模型进行训练,有望提供全新的算力供应模式和削减训练成本.针对此方法存在的隐私风险、恶意攻击和信任缺失问题,提出基于区块链的大模型微调算力共享平台CompuDEX.充分利用区块链技术去信任、匿名的特性,提供无需信任中介且保护用户隐私的交易平台.利用智能合约和密码学工具促使算力提供者公平竞争,以进一步降低训练成本.基于零知识证明设计“红气球”激励机制与安全性方案,用于识别算力提供者的恶意行为并追责.通过对微调方法 LoRA的结构进行拆分,在不增加额外计算开销的前提下保护训练过程中的数据隐私.实验结果表明,在微调的前向传播阶段,计算成本仅为国内主流云服务提供商的8%~14%.通过增加并行节点的数量,运行时间可以从本地训练所需时间的175%显著减少到20%,甚至更低. 展开更多
关键词 区块链 大模型 微调 外包计算 隐私保护
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面向数字素养培育的数字创作:理论与实践
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作者 周均奕 刘孛 尚俊杰 《华东师范大学学报(教育科学版)》 北大核心 2026年第1期94-104,共11页
数字素养的培育刻不容缓。作为数字素养的高阶表现与重要的培育手段,数字创作已经成为了数字教育的关键议题。当前,我国的数字创作教育尚处于初步阶段,教育实施路径亟需系统化的理论指导与实践指引。在此背景下,本研究深入研讨了数字创... 数字素养的培育刻不容缓。作为数字素养的高阶表现与重要的培育手段,数字创作已经成为了数字教育的关键议题。当前,我国的数字创作教育尚处于初步阶段,教育实施路径亟需系统化的理论指导与实践指引。在此背景下,本研究深入研讨了数字创作与数字素养的交织关系,梳理了数字创作从文本、程序进阶到多媒体、元宇宙的发展历程,构建了基于数字素养框架的数字创作概念内涵,并指明了其多模态、智能化、普惠性、个性化、拓展性的5大表现特征。在理论基础方面,本研究重点论述了建造主义和人机交互理论对于理解数字创作的重要价值。此外,本研究梳理了数字创作在教学中的3大范式:工具掌握的渐进训练、学科融合的转化学习与项目驱动的综合创作,为数字创作的实践落地提供参考。最后,本研究提出了数字创作在政策支持、研发支持和教学支持三方面的发展建议。 展开更多
关键词 数字创作 数字素养 建造主义 人机交互
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CT值直方图分析对牙源性角化囊肿与颌骨造釉细胞瘤鉴别诊断的价值
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作者 王瑞清 周锐志 +2 位作者 徐琦 杨志涛 陈海松 《精准医学杂志》 2026年第1期58-61,共4页
目的探讨基于多层螺旋CT(MSCT)的CT值直方图分析对牙源性角化囊肿(odontogenic keratocystic,OKC)与颌骨造釉细胞瘤(ameloblastoma,AME)鉴别诊断的价值。方法将经病理证实的32例OKC以及59例颌骨AME患者纳入研究,利用FireVoxel软件进行... 目的探讨基于多层螺旋CT(MSCT)的CT值直方图分析对牙源性角化囊肿(odontogenic keratocystic,OKC)与颌骨造釉细胞瘤(ameloblastoma,AME)鉴别诊断的价值。方法将经病理证实的32例OKC以及59例颌骨AME患者纳入研究,利用FireVoxel软件进行图像处理及直方图分析,得到各自直方图参数,包括病灶CT值的平均值、标准差、方差、变异系数、偏度、峰度、熵值、1st及5th、10th、25th、50th、75th、90th、95th、99th百分位数。采用两独立样本t检验或Mann Whitney U检验比较OKC及颌骨AME间直方图参数差异。采用受试者操作特征(ROC)曲线分析判断各参数的诊断效能,并计算曲线下面积(AUC)。结果OKC及颌骨AME的直方图参数5th、10th百分位数存在显著差异(Z=4.486、2.058,P<0.05),其中5th百分位数的AUC最大,为0.835,其诊断效能最高时的ROC曲线截断值为-4 HU。结论基于MSCT的CT值直方图分析有助于OKC及颌骨AME的鉴别诊断,其中5th百分位数的诊断效能最佳。 展开更多
关键词 牙源性囊肿 成釉细胞瘤 多探头的计算机断层扫描 直方图分析 诊断 鉴别
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基于增强CT图像的纹理分析对胃癌患者区域淋巴结转移的评估价值
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作者 熊瑶 李天然 郭玉林 《精准医学杂志》 2026年第1期46-49,共4页
目的探讨基于增强CT图像的纹理分析对胃癌患者区域淋巴结转移的评估价值。方法收集174例病理确诊为胃癌并行胃癌根治术患者的临床资料。将所有患者依据术后病理结果分为非淋巴结转移组49例和淋巴结转移组125例。采用CT Kinetics纹理分... 目的探讨基于增强CT图像的纹理分析对胃癌患者区域淋巴结转移的评估价值。方法收集174例病理确诊为胃癌并行胃癌根治术患者的临床资料。将所有患者依据术后病理结果分为非淋巴结转移组49例和淋巴结转移组125例。采用CT Kinetics纹理分析软件提取两组患者腹部增强CT图像胃癌原发灶的8个纹理特征参数(平均值A、偏度A、峰度A、熵A、平均值V、偏度V、峰度V、熵V)并进行比较,绘制ROC曲线分析胃癌原发灶CT纹理特征参数对区域淋巴结转移的评估效能。结果淋巴结转移组与非淋巴结转移组胃癌原发灶的熵A、熵V比较差异具有显著性(t=-5.592、-5.557,P<0.05),而平均值A、偏度A、峰度A、平均值V、偏度V、峰度V两组间比较均无显著差异(P>0.05)。熵A、熵V评估胃癌患者区域淋巴结转移的ROC曲线下面积(AUC)分别为0.751、0.754,截断值分别为9.47、9.84,灵敏度分别为74.4%、56.8%,特异度分别为69.4%、85.7%。结论基于增强CT图像的胃癌原发灶纹理分析对区域淋巴结性质有一定的评估价值,其纹理特征参数熵A、熵V升高,提示肿瘤异质性更高,发生区域淋巴结转移的可能性更高。 展开更多
关键词 胃肿瘤 淋巴转移 体层摄影术 X线计算机 图像处理 计算机辅助 纹理分析
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天然气烧嘴参数对锌精馏炉塔盘传热性能的影响研究
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作者 林保平 杜志俊 +3 位作者 曾平生 黄正宗 伍东玲 刘柳 《有色金属(冶炼部分)》 北大核心 2026年第1期20-29,共10页
塔式锌精馏炉在用天然气替代煤气的过程中,出现燃烧室内积炭、温度分布不均等问题,导致塔盘热流密度与炉体产能降低。天然气烧嘴参数对其燃烧过程有着重要影响,进而对塔盘传热性能及精馏生产效率等重要指标有显著影响。为提高锌精馏炉... 塔式锌精馏炉在用天然气替代煤气的过程中,出现燃烧室内积炭、温度分布不均等问题,导致塔盘热流密度与炉体产能降低。天然气烧嘴参数对其燃烧过程有着重要影响,进而对塔盘传热性能及精馏生产效率等重要指标有显著影响。为提高锌精馏炉的产能、降低能耗,本文基于计算流体力学(CFD)方法,对不同烧嘴内径与结构下燃烧室内天然气燃烧过程进行了数值模拟,明确了各因素对炉内燃烧与传热的作用规律,并提出了相应的优化方案。结果表明:增大烧嘴内径可改善炉况,但需控制增大幅度以规避回火风险;喇叭型烧嘴口加装钝体可强化气团混合与辐射传热,有效改善炉膛下部低温问题,提升塔盘温度均匀性,是兼顾烟气覆盖范围与燃烧效率的优选方案;当烧嘴内径均为120 mm时,直筒型烧嘴因出口无扩张使射流流速更高,卷吸高温空气能力与气团混合效果更优,炉膛温度分布更均匀,传热性能相较于喇叭型烧嘴表现更好。本研究结论可为塔式锌精馏炉的结构优化提供理论依据。 展开更多
关键词 塔式锌精馏炉 天然气燃烧 烧嘴 塔盘 计算流体力学
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