期刊文献+
任意字段
题名或关键词
题名
关键词
摘要
作者
第一作者
机构
刊名
分类号
参考文献
作者简介
基金资助
栏目信息
共找到11,298篇文章
< 1 2 … 250 >
每页显示 20 50 100
已选0条
引用分析
参考文献
引证文献
 统计分析
检索结果
已选文献
显示方式：
Local Rate of Convergence in the Functional Limit Theorem for Increments of a Fractional Brownian Motion 认领 引用 被引量：1
1
作者 LIU Yonghong DING Ding ZHOU Xia 《数学进展》 CSCD 北大核心 2025年第1期197-211,共15页
In this paper,we present local functional law of the iterated logarithm for Cs?rg?-Révész type increments of fractional Brownian motion.The results obtained extend works of Gantert[Ann.Probab.,1993,21(2):104... In this paper,we present local functional law of the iterated logarithm for Cs?rg?-Révész type increments of fractional Brownian motion.The results obtained extend works of Gantert[Ann.Probab.,1993,21(2):1045-1049]and Monrad and Rootzén[Probab.Theory Related Fields,1995,101(2):173-192]. 展开更多
关键词 fractional Brownian motion increment local functional law of the iterated logarithm large deviation small deviation
暂未订购 下载PDF
Prediction model for indoor rock compression failure time based on ensemble learning and optimization algorithms 认领 引用 被引量：1
2
作者 Boyang Zhang Xiancheng Wang +5 位作者 Fei Ding Liyuan Yu Luyuan Wu Shuai Zhao Yingkang Weng Zhaoyang Feng 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2026年第7期2437-2453,共17页
The prediction of rock failure,a key fundamental research for addressing mining safety issues(such as mine slope stability and rockburst),faces challenges with traditional methods due to their complex generalization a... The prediction of rock failure,a key fundamental research for addressing mining safety issues(such as mine slope stability and rockburst),faces challenges with traditional methods due to their complex generalization and computational processes that struggle to describe the entire failure process.Consequently,12 prediction models integrating ensemble learning and optimization algorithms were established to predict rock peak stress and failure time using strain,elastic modulus,density,mass,and confining pressure as inputs.Fivefold cross-validation was used to optimize hyperparameters,significantly improving the model's generalization ability,robustness,and stability.Dataset was established through rock mechanics experiments,with strain increments configured at 0.008‰,0.01‰,and 0.012‰ in the test set.The cross-validation optimized particle swarm optimization eXtreme gradient boosting(CV-PSO-XGBoost)model performed best under a strain increment of 0.01‰,and its stress prediction achieved coefficient of determination R2=0.904,mean absolute error(MAE)=4.315,and root mean square error(RMSE)=5.435;while the failure time prediction demonstrated R2=0.811,mean absolute percentage error(MAPE)=7.842%,and MAE=30.343.Finally,SHapley Additive explanations(SHAP)analysis showed strain and stress significantly impact the model,with strain positively predicting failure time,aligning with traditional rock validating reliability.This study provides insights into the research on rock strata stability in mining. 展开更多
关键词 rock failure strain increment failure time ensemble learning SHapley Additive exPlanations interpretation
暂未订购 下载PDF
Minimum Number of Load Increments in Second-Order Elastic Analyses of Steel Frames 认领 引用
3
作者 Nadine Faramawi Barry T.Rosson 《Journal of Civil Engineering and Architecture》 2025年第11期523-527,共5页
A relationship was discovered between the amplification factor and the number of load increments that are needed to limit the relative error to one percent in second-order elastic analyses with a predictor-corrector s... A relationship was discovered between the amplification factor and the number of load increments that are needed to limit the relative error to one percent in second-order elastic analyses with a predictor-corrector solution scheme.Previous research by the authors proposed a design equation to determine the required minimum number of load increments based on an evaluation of the elastic critical buckling load ratio.Further research has shown that an approximate amplification factor equation that is based on the B2 multiplier equation produces similar results when the amplification factor is less than approximately four.Eleven moment frames are used to verify the use of the new approximate amplification factor in the proposed design equation. 展开更多
关键词 Nonlinear geometric analysis amplification factor load increment structural frame
暂未订购 下载PDF
Radar Data Assimilation with EnKF-IAU:Impacts on Dynamical Structure and Short-term Prediction of Landfalling Typhoon Bebinca(2024) 认领 引用
4
作者 Zhaoyang HUO Wei HUANG +3 位作者 Gengjiao YE Mengjuan LIU Wanchen WU Yubao LIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2026年第6期1226-1242,共17页
Landfalling tropical cyclones(LTCs)undergo rapid structural adjustments and complex nonlinear interactions in coastal regions,making short-term prediction of heavy rainfall and damaging winds particularly challenging.... Landfalling tropical cyclones(LTCs)undergo rapid structural adjustments and complex nonlinear interactions in coastal regions,making short-term prediction of heavy rainfall and damaging winds particularly challenging.Conventional intermittent data assimilation often introduces dynamical imbalances into the analysis fields,which may further deteriorate subsequent forecasts.This study investigates the landfall process of Typhoon Bebinca(2024)and systematically evaluates a set of ensemble-based assimilation experiments conducted within an Incremental Analysis Update(IAU)framework,incorporating multiple observation types,including radar reflectivity,Doppler radial velocity,and surface measurements.The results show that the IAU technique,through the gradual application of analysis increments within a four-dimensional time window,effectively suppresses initialization shocks,alleviates spurious dynamical imbalance,and preserves flowdependent coordination.The IAU-based framework efficiently retains observational information,optimizes vortex structure,intensifies the warm core,and promotes the formation of a vertically coherent subsidence column within the eye region,thereby strengthening the secondary circulation.In addition,the IAU scheme also helps establish a more consolidated and axisymmetric moisture core,accompanied by a sea-level pressure field with smoother and dynamically coherent gradient structures,indicating a more physically balanced thermodynamic–dynamic coupling.These balanced analyses translate into more accurate forecasts of track,intensity evolution,and landfall-induced precipitation.Overall,the IAU-enhanced ensemble assimilation system substantially improves the physical consistency of storm analyses and significantly increases the short-term predictability of LTC track,rainfall,and wind hazards over coastal urban regions. 展开更多
关键词 data assimilation incremental analysis update landfalling tropical cyclones model imbalances dynamical structure
暂未订购 下载PDF
Radial growth and its temporal stability of Dahurian larch in the southern boreal forest: Divergent trends during climate warming and warming hiatus 认领 引用
5
作者 Zhongtong Peng Enzai Du +2 位作者 Yang Tang Tao He Yuehan Tian 《Forest Ecosystems》 SCIE CAS CSCD 2026年第2期321-330,共10页
Climate warming has reshaped the structure and function of global boreal forest with expected negative impacts at its southern margins.A warming hiatus has occurred in many high-latitude regions in recent decades,but ... Climate warming has reshaped the structure and function of global boreal forest with expected negative impacts at its southern margins.A warming hiatus has occurred in many high-latitude regions in recent decades,but its impacts on tree growth in the southern boreal forest remain unclear.We sampled tree rings of Dahurian larch(Larix gmelinii)in the southern boreal forest of the Greater Khingan Mountains(GKM)and examined the trends of tree growth and its temporal stability based on the age-detrended basal area increment(BAI)for the periods of rapid warming(1962-1992)and warming hiatus(1993-2022).The results indicate that age-detrended BAI declined significantly during the warming period,while it showed no further decrease during the period of warming hiatus.Tree growth decline was associated with higher daily maximum air temperature in the main growing season and daily minimum air temperature in the non-growing season,as well as lower precipitation in the early growing season and daily minimum air temperature in the main growing season.During the warming hiatus,tree growth was positively regulated by the precipitation in the non-growing season,daily maximum air temperature in the early growing season,and daily minimum air temperature in the main growing season,but negatively affected by the daily maximum air temperature in the late growing season.Intriguingly,tree growth stability declined significantly during the warming period and recovered rapidly during the period of warming hiatus.The decline in tree growth stability was mainly explained by increasing daily minimum air temperature in the non-growing season.The recovery of tree growth stability was associated with lower precipitation in the non-growing season,higher interannual stability of daily maximum air temperature in the early growing season,higher interannual mean value and stability of daily maximum air temperature in the late growing season,and lower interannual mean value and stability of daily minimum air temperature in the main growing season.Our findings highlight a rapid recovery of tree growth stability instead of growth rate during the warming hiatus following a period of rapid warming and provide new insights into the decadal-scale resilience of the southern boreal forest in response to climate change. 展开更多
关键词 Basal Area Increment Boreal tree Dahurian larch Decadal-scale resilience Interannual variability Temperature stress Temporal stability Warming hiatus
暂未订购 下载PDF
Multivariate Adjustment in the IAU-Based Tropical Cyclone Initialization Scheme in the TRAMS Model 认领 引用
6
作者 Shaojing ZHANG Jeremy Cheuk-Hin LEUNG +6 位作者 Daosheng XU Liwen WANG Yuxiao CHEN Yanyan HUANG Suhong MA Wenshou TIAN Banglin ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2026年第2期436-450,I0027-I0031,共15页
The operational Tropical Regional Atmospheric Model System(TRAMS)often underestimates initial typhoon intensity when using the global analysis field as the initial condition.The TRAMS tropical cyclone(TC)initializatio... The operational Tropical Regional Atmospheric Model System(TRAMS)often underestimates initial typhoon intensity when using the global analysis field as the initial condition.The TRAMS tropical cyclone(TC)initialization scheme,developed based on the incremental analysis updates(IAU)technique,effectively reduces initial bias.However,the original IAU-based TC initialization scheme only adjusts the wind field at the analysis moment,with other variables adjusted implicitly under the model's constraints according to a gradually inserted wind increment(named“univariate adjustment scheme”hereafter).The univariate adjustment scheme requires approximately 3 h to reach a dynamic equilibrium state,which constrains the assimilation of hourly TC observations and causes excessive dissipation of meaningful short-wave information in adjustment increments.To address this limitation,this study develops a multivariate adjustment IAU-based TC initialization scheme that incorporates gradient wind balance and hydrostatic balance as its largescale constraints.Numerical experiments with TC Hato(2017)demonstrate that the multivariate adjustment scheme reduces the IAU relaxation time to 1 h while marginally improving forecast skill.These findings are consistently replicated across 12 additional TC cases.The development of the IAU-based multivariate adjustment initialization scheme establishes a foundation for 4-D initialization using hourly TC observations. 展开更多
关键词 tropical cyclone initialization multivariate adjustment incremental analysis updates numerical prediction
暂未订购 下载PDF
Performance analysis of RIS-aided incremental-relaying wireless communication systems 认领 引用
7
作者 Manlin Fang Min Deng +2 位作者 Jun Yang Saifullah Adnan Zhen Chen 《Digital Communications and Networks》 SCIE EI CSCD 2026年第2期388-395,共8页
The emerging sixth-generation networks demand ultra-high-speed wideband transmissions.In this context,this study proposes a novel Reconfigurable Intelligent Surface(RIS)-aided Incremental Relaying(IR)scheme that combi... The emerging sixth-generation networks demand ultra-high-speed wideband transmissions.In this context,this study proposes a novel Reconfigurable Intelligent Surface(RIS)-aided Incremental Relaying(IR)scheme that combines the complementary benefits of RISs and relay systems to enhance the achievable rate.In the proposed system,a relay is exploited to retransmit the source signal when the destination fails to decode the RIS-aided signal correctly.To assess the system performance,we analytically derive closed-form expressions for the outage probability and throughput of the RIS-aided IR scheme,using the central limit theorem.Simulation results validate the analytical findings and reveal that the proposed RIS-aided IR scheme significantly outperforms the conventional pure RIS and hybrid RIS-relay schemes in terms of both outage probability and throughput,highlighting its potential for improving communication-system performance. 展开更多
关键词 Reconfigurable intelligent surface Incremental relaying Outage probability System throughput
暂未订购 下载PDF
Predicting high-temperature necking evolution with significant strain-rate gradients in Ti6Al4V titanium alloy 认领 引用
8
作者 Yao Zhou Qi Hu +1 位作者 Xinxi Liu Jun Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2026年第6期394-415,共22页
Necking evolution of Ti6Al4V titanium alloy under high-temperature tension at low strain rates is a typical non-uniform deformation with significant strain-rate gradients.Accurately predicting this process contributes... Necking evolution of Ti6Al4V titanium alloy under high-temperature tension at low strain rates is a typical non-uniform deformation with significant strain-rate gradients.Accurately predicting this process contributes to revealing materials’flow behavior during non-uniform and large plastic deformation.In this work,tensile tests conducted at 700°C and microstructure characterization indicate that the flow behavior of Ti6Al4V exhibits pronounced strain-rate sensitivity and dynamic recrystallization-induced strain softening.Employing a hybrid experimental-numerical strategy,a physically based model is validated as an effective approach for extrapolating post-necking flow stress curves.Subsequently,two phenomenological models are calibrated using these flow stress curves.By deriving the stress updating algorithms in an implicit finite element method,three visco-plastic models are utilized to simulate tension processes with necking evolution.The results suggest that the physically based model predicts tensile necking processes more accurately compared to phenomenological models,despite using similar flow stress curves.The necking evolution simulated by phenomenological models is notably retarded due to the lack of strain-rate history effects.In contrast,the physically based model,which records the strain-rate history,predicts lower flow stress in the necking center but higher flow stress in regions farther from the center,thereby promoting necking localization.Besides,large time increments in simulations fail to capture strain-rate gradients in necking regions,and a recommended time increment is provided to ensure stable simulations of necking evolution. 展开更多
关键词 Necking evolution Strain-rate gradient Visco-plastic model Finite element method Strain-rate history Time increment
暂未订购 下载PDF
Calculation of fill foundation deformation based on a modified unsaturated soil constitutive model 认领 引用
9
作者 YANG Xiaohui ZHAO Zhizhong +1 位作者 GUO Nan ZHU Yanpeng 《Journal of Mountain Science》 SCIE CSCD 2026年第2期869-889,共21页
Deformations in high fill foundations comprising soil–stone mixtures must be accurately predicted to ensure construction quality and long-term operational safety.However,existing computational and analytical methods ... Deformations in high fill foundations comprising soil–stone mixtures must be accurately predicted to ensure construction quality and long-term operational safety.However,existing computational and analytical methods inadequately capture their complex mechanical behavior.We conducted a series of triaxial tests on unsaturated soil samples collected from a high fill project site in northwestern China under three stress paths.The incremental nonlinear and elastoplastic constitutive models for unsaturated soils were modified,and a calculation method was developed for the vertical and lateral deformations of high fill foundations using the layered summation approach.The results indicate that for soil samples with the same mixing ratio(m)and compaction coefficient(n),the strength of the sample and its tendency to exhibit shear dilation increase with the net confining pressure or matric suction.Additionally,the stress–strain curve of the soil sample gradually changes from the strain-hardening type to the ideal elastoplastic type as the compaction coefficient increases.Moreover,the compaction coefficient is an important factor influencing the magnitude of yield stress and yield suction in soil samples,and the yield points of both are similar in shape to the loadingcollapse(LC)and suction increase(SI)yield lines obtained using the Barcelona model in the net mean stress-generalized shear stress(p-s)plane,respectively.The modified incremental nonlinear instantaneous model simultaneously considers the effects of the compaction coefficient,suction and mixing ratio,and the model parameter can be simplified to the tangential modulus expression in the Duncan-Chang model when the suction is zero.Furthermore,the modified elastoplastic constitutive model,which considers the effects of the net mean stress,suction and partial stress,can be simplified to the elastoplastic constitutive relationship of saturated soil when the suction is zero.The proposed deformation calculation method,based on the layered summation theory,is applicable to both elastic and elastoplastic foundation states,as confirmed through numerical simulations.Our work can be used as a reference for the calculation of foundation deformation in similar mixed material high fill projects. 展开更多
关键词 High fill engineering Unsaturated soil triaxial test Incremental non-linear constitutive model Elastoplastic constitutive model Layered summation method Foundation deformation calculation
暂未订购 下载PDF
A GENERAL FORM OF THE INCREMENTS OF A TWO-PARAMETER WIENER PROCESS 认领 引用 被引量：3
10
作者 林正炎 陆传荣 《Applied Mathematics(A Journal of Chinese Universities)》 1993年第1期54-63,共10页
In this paper, we consider a general form of the increments for a two-parameter Wiener process. Both the Csorgo-Revesz's increments and a class of the lag increments are the special cases of this general form of i... In this paper, we consider a general form of the increments for a two-parameter Wiener process. Both the Csorgo-Revesz's increments and a class of the lag increments are the special cases of this general form of increments. Our results imply the theorem that have been given by Csorgo and Revesz (1978), and some of their conditions are removed. 展开更多
关键词 Two-parameter Wiener Process Increments.
暂未订购 下载PDF
A Dual-Component Elastic Adaptation Network for Rotating Machinery Incremental Fault Diagnosis under Variable Operating Conditions 认领 引用
11
作者 Yan Zhang Changqing Shen +3 位作者 Xiaofen Ye Liang Chen Juanjuan Shi Zhongkui Zhu 《Journal of Dynamics, Monitoring and Diagnostics》 2026年第1期49-63,共15页
In practical industrial environments,the data distribution of rotating machinery drifts as operating conditions vary,causing a marked deterioration in the performance of traditional fault diagnosis methods that rely o... In practical industrial environments,the data distribution of rotating machinery drifts as operating conditions vary,causing a marked deterioration in the performance of traditional fault diagnosis methods that rely on the assumption of identical distributions.Incremental learning provides a promising pathway to address dynamic operating conditions.However,existing approaches typically depend on replaying historical data and still struggle to strike a balance between stability and plasticity.To overcome these limitations,this paper proposes a dual-component elastic adaptive network(DCEAN)designed for incremental fault diagnosis of rotating machinery under varying working conditions.The proposed framework operates without access to previous data and simultaneously achieves knowledge retention and feature correction.Specifically,a sensitive parameter constraint(SPC)mechanism is introduced to curb excessive updates to parameters identified as critical,thereby stabilizing previously learned knowledge.In parallel,a feature drift self-calibration(FDSC)mechanism is employed to estimate and compensate for distribution shifts induced by condition variations,promoting consistency of feature representations across domains.Through the coordinated action of these two mechanisms,DCEAN establishes an incremental learning paradigm that harmonizes stability with adaptability.Two case studies demonstrate that the proposed method delivers superior diagnostic performance in variable operating environments,underscoring its robustness and effectiveness. 展开更多
关键词 feature drift incremental learning intelligent fault diagnosis rotating machinery variable operating conditions
暂未订购 下载PDF
赛事“流量”到经济“增量”:新时代体育赛事“三进”的理论逻辑、现实困境与发展路径 认领 引用 被引量：4
12
作者 王洪玉 张小林 李雙 《北京城市学院学报》 2026年第1期76-85,共10页
在当前经济环境下,进街区打造全民参与体系、进商圈重构城市空间体育、进景区孵化体旅新业态,以实现经济“增量”目标。但“三进”执行需因地制宜,且当前赛事“流量”转经济“增量”的理论路径尚不明确,实践中面临范式模糊、载体羸弱,... 在当前经济环境下,进街区打造全民参与体系、进商圈重构城市空间体育、进景区孵化体旅新业态,以实现经济“增量”目标。但“三进”执行需因地制宜,且当前赛事“流量”转经济“增量”的理论路径尚不明确,实践中面临范式模糊、载体羸弱,社区商圈景区存在局限,现代与民俗体育观念错位等难题。因此,需以体育产业现代治理思路深化对体育与经济社会关系的认识,为“三进”明确发展方向,推动体育产业以赛事为抓手根植基层,成为国家经济社会发展的重要支撑。 展开更多
关键词 体育赛事 经济 增量 三进 流量
暂未订购 下载PDF
基于综合耗量的储能集群二次调频功率优化策略 认领 引用 被引量：2
13
作者 郑子萱 陈恩泽 +6 位作者 李杰 张家琛 肖先勇 黄松涛 尚国政 陶以彬 朱少杰 《中国电机工程学报》 EI CSCD 北大核心 2026年第7期2796-2808,I0014,共13页
在储能集群协同参与自动发电控制(automatic generation control,AGC)过程中,调频功率指令的合理分配是确保指令有效执行、发挥储能资源调频优势的重要保障。针对当前AGC指令分配过程未充分考虑储能电站各类损耗的综合影响,可能造成调... 在储能集群协同参与自动发电控制(automatic generation control,AGC)过程中,调频功率指令的合理分配是确保指令有效执行、发挥储能资源调频优势的重要保障。针对当前AGC指令分配过程未充分考虑储能电站各类损耗的综合影响,可能造成调频成本抬高、资源浪费等问题,提出一种基于综合耗量的储能集群二次调频功率优化策略。首先,考虑AGC的基本流程,从调频指令生成、分配到执行3个部分,层次化设计储能集群参与AGC调节的协同控制架构;其次,充分挖掘储能电站参与调频过程的各类调节损耗,构建综合耗量函数,并以耗量最小为目标确立每轮AGC控制周期的动态最优组合方案;最后,在组合方案确定的基础上,采取等微增率准则分配调频功率,并利用迭代修正法处理出力越限电站。通过仿真分析验证了所提策略能确保AGC指令的有效执行,降低储能集群参与AGC调控的总体损耗,并减少储能集群的平均动作次数。 展开更多
关键词 自动发电控制 储能集群 动态组合 等微增率准则 功率分配
暂未订购 下载PDF
基于轻量化SE-ResNet和增量学习的铣刀磨损状态预测方法 认领 引用 被引量：1
14
作者 李孝斌 王云龙 +2 位作者 尹超 李波 肖博 《计算机集成制造系统》 EI CSCD 北大核心 2026年第1期91-104,共14页
在航空叶片、精密轴承等典型零件的铣削加工过程中,工况变化会引起数据分布变化,这使得基于有限历史工况数据训练的模型难以适应新工况的数据分布,从而导致模型在变工况下的预测性能下降。针对上述问题,提出一种基于轻量化压缩激励残差... 在航空叶片、精密轴承等典型零件的铣削加工过程中,工况变化会引起数据分布变化,这使得基于有限历史工况数据训练的模型难以适应新工况的数据分布,从而导致模型在变工况下的预测性能下降。针对上述问题,提出一种基于轻量化压缩激励残差网络(SE-ResNet)和增量学习的铣刀磨损状态预测方法。该方法利用轻量化SE-ResNet模型参数少、便于更新的特点,在预训练阶段完成模型的初始化,并通过增量学习在新工况数据上逐步更新模型,以适应变化的数据分布,从而提高变工况条件下铣刀磨损状态预测的准确性。实验结果表明,相较于多种对比方法,所提方法在变工况条件下具有更优的预测性能。 展开更多
关键词 变工况 增量学习 铣刀磨损状态预测 SE注意力机制
暂未订购 下载PDF
基于ISSA-GPR的锂离子电池健康状态估计 认领 引用 被引量：7
15
作者 张梦迪 刘洋 +3 位作者 陈健 吉金鹏 姚智伟 公衍勇 《电源学报》 CSCD 北大核心 2026年第2期233-243,共11页
由于电池健康状态SOH(state-of-health)难以被直接测量,因此对SOH的准确估计对保证电池安全运行至关重要。基于此,提出了1种改进麻雀搜索算法优化高斯过程回归ISSA-GPR(improved sparrow search algorithm-Gaussian process regression... 由于电池健康状态SOH(state-of-health)难以被直接测量,因此对SOH的准确估计对保证电池安全运行至关重要。基于此,提出了1种改进麻雀搜索算法优化高斯过程回归ISSA-GPR(improved sparrow search algorithm-Gaussian process regression)锂离子电池健康状态估计方法。首先采用改进麻雀搜索算法优化高斯过程回归模型参数,构建基于改进麻雀搜索算法的高斯过程回归模型;然后分析容量增量曲线,提取表征电池容量退化的健康因子作为模型的输入,并通过改进麻雀搜索算法确定以峰值为中心峰面积的最佳电压区间长度,进而得到电池健康状态估计模型;最后利用公开的实验数据集进行验证。结果表明,所提ISSA-GPR方法能够对电池健康状态进行准确估计。 展开更多
关键词 锂离子电池 健康状态 容量增量曲线 健康因子 麻雀搜索算法 高斯过程回归
暂未订购 下载PDF
An empirical study on cross-phase code modification behaviors in incremental programming projects 认领 引用
16
作者 Jing Jiang Chenhong Ji +1 位作者 Li Zhang Haiyan Yang 《计算机教育》 2026年第6期280-291,共12页
This paper conducts an empirical study on students'code modification behaviors in incremental programming projects by analyzing 40771 code submissions from 371 students through abstract syntax tree(AST)difference ... This paper conducts an empirical study on students'code modification behaviors in incremental programming projects by analyzing 40771 code submissions from 371 students through abstract syntax tree(AST)difference analysis and manual annotation.The study investigates the distribution of code modification types to prior-phase code during iterative development,identifies cross-phase error types,and analyzes refactoring strategies.The findings reveal that error correction and code refactoring constitute the primary types of cross-phase code modifications.Among cross-phase latent errors,special case neglect represents the dominant error type,indicating insufficient coverage of special scenarios in existing test suites.Variable renaming emerges as the most prevalent refactoring behavior,reflecting students'emphasis on code readability.These research findings provide empirical evidence for optimizing incremental curriculum design,improving test cases,and cultivating students'code maintenance capabilities in programming education. 展开更多
关键词 Incremental projects Code modification Error correction Code refactoring Computer science education
暂未订购 下载PDF
钢框架-附加装配式RC/UHTCC抗侧力墙结构抗震性能及易损性分析 认领 引用 被引量：2
17
作者 白亮 周天华 +2 位作者 蒋路 白旭 王斌 《土木工程学报》 EI CSCD 北大核心 2026年第2期20-34,共15页
超高韧性水泥基材料(ultra high toughness cementitious composites,UHTCC)耐损伤能力强、裂缝控制能力好,具有超高的受压韧性及显著的受拉应变硬化特性。为提升钢框架结构的抗侧性能,分别将装配式RC、UHTCC抗侧力墙作为钢框架结构的... 超高韧性水泥基材料(ultra high toughness cementitious composites,UHTCC)耐损伤能力强、裂缝控制能力好,具有超高的受压韧性及显著的受拉应变硬化特性。为提升钢框架结构的抗侧性能,分别将装配式RC、UHTCC抗侧力墙作为钢框架结构的抗侧力构件,进行足尺钢框架(STF)、钢框架-附加装配式RC抗侧力墙(SRCW)和钢框架-附加装配式UHTCC抗侧力墙(SHTCW)试件低周往复加载试验,对上述试件破坏模式、滞回性能、刚度、承载力、变形能力、应变及耗能性能等进行研究。试验表明,试件SHTCW、SRCW的峰值承载力相比于试件STF分别提高了25%和13%,抗侧力墙材料抗压强度值相近的情况下,试件SHTCW的峰值承载力较试件SRCW提高15%。相同加载位移角下,试件SHTCW的抗侧刚度及等效黏滞阻尼系数高于试件SRCW和STF,相比于RC抗侧力墙,UHTCC抗侧力墙具有更优异的抗侧性能及耗能能力,其与钢框架的变形协调能力更好。在试验研究基础上,采用OpenSees有限元程序,分别对STF、SRCW结构与SHTCW结构进行增量动力分析,相比于STF结构,SHTCW、SRCW结构各个性能水准的失效概率明显降低,倒塌储备系数分别提高了1.42和1.18倍,通过附加装配式UHTCC抗侧力墙,能够减轻地震荷载作用下钢框架结构的动力响应,有效提升钢框架结构抗震性能。 展开更多
关键词 钢框架 超高韧性水泥基材料 装配式抗侧力墙 抗震性能 增量动力分析
暂未订购 下载PDF
典型工业城市夏季VOCs污染特征、来源及臭氧生成机制研究 认领 引用 被引量：1
18
作者 刘桓嘉 赵幸子 +7 位作者 马琳 贾梦珂 许梦源 张硕 李峒乐 姚丹 程轲 徐雅迪 《环境科学学报》 CAS CSCD 北大核心 2026年第2期14-27,共14页
为探究典型工业城市挥发性有机物(VOCs)的污染演变规律、来源特征、化学反应活性及臭氧生成机制,于2022年7月在新乡市开展了在线连续外场观测.结果表明,总挥发性有机化合物(TVOCs)的平均浓度为(38.0±5.2)×10-9,主要VOCs成... 为探究典型工业城市挥发性有机物(VOCs)的污染演变规律、来源特征、化学反应活性及臭氧生成机制,于2022年7月在新乡市开展了在线连续外场观测.结果表明,总挥发性有机化合物(TVOCs)的平均浓度为(38.0±5.2)×10-9,主要VOCs成分是烷烃(32%).利用正交矩阵因子分析(PMF)模型解析了5类排放源,分别为工业源(25.6%)、溶剂使用源(22.4%)、机动车尾气排放源(20.6%)、植物源(11.3%)、液化石油气(LPG)和生物质燃烧源(20.1%).·OH消耗速率(LOH)和臭氧生成潜势(OFP)的研究结果一致表明,烯烃和含氧挥发性有机物(OVOCs)是化学活性最高的物种,对O3的生成贡献最大,因此,控制烯烃和OVOCs的浓度更有利于减少该工业城市O3的生成.夏季O3污染时段本地净O3生成速率为(31.5±13.2)×10-9 h-1,O3的生成以过氧自由基(HO2·)与NO反应为主;基于观测的模型(Observation-Based Model,OBM)的研究结果,该区域O3生成主要受VOCs控制,其中烯烃对夏季O3生成的贡献最大. 展开更多
关键词 挥发性有机物(VOCs) 来源解析 基于观测的模型(OBM) 臭氧收支 相对增量反应活性(RIR) 新乡
暂未订购 下载PDF
基于大模型文档知识抽取的领域知识图谱增量构建 认领 引用 被引量：1
19
作者 陈俊臻 王淑营 罗浩然 《计算机工程与应用》 EI CSCD 北大核心 2026年第5期191-203,共13页
针对工业领域知识图谱构建中面临的标注样本稀缺、文档多源异构、语义结构复杂等挑战,提出一种基于大型预训练语言模型的领域知识图谱增量构建方法LLM-KG。该方法利用GPT-4模型自动生成高质量的标注样本,降低人工标注成本的同时提升训... 针对工业领域知识图谱构建中面临的标注样本稀缺、文档多源异构、语义结构复杂等挑战,提出一种基于大型预训练语言模型的领域知识图谱增量构建方法LLM-KG。该方法利用GPT-4模型自动生成高质量的标注样本,降低人工标注成本的同时提升训练数据的覆盖性与准确性;借助LoRA(low-rank adaptation)技术对轻量级语言模型进行领域微调,实现对领域文档中实体与关系的高精度抽取。为提升新增实体和关系的对齐质量,LLM-KG引入语义块划分机制,并结合向量数据库进行Top-k实体召回,最终由大语言模型对召回结果进行语义一致性判断与筛选,从而实现更加准确的实体融合与关系补全。在公开数据集DDI及风电装备数据集上进行了实验验证,结果表明,LLM-KG在准确率、召回率和F1值上均优于对比方法,展现出良好的领域适应性与增量构建能力。 展开更多
关键词 知识图谱(KG) 大模型微调 文档信息抽取 增量构建
暂未订购 下载PDF
基于非线性分析的顶推计算方法研究 认领 引用 被引量：1
20
作者 莫山峰 黄才良 覃晖 《中外公路》 CAS 2026年第3期184-193,共10页
针对传统顶推计算方法及顶推梁体拼装施工控制的不足,该文提出了一种基于非线性分析的顶推计算方法,可真实模拟顶推支墩不动、梁体前移的运行状态。该方法可直接给出梁体所有节段的拼装线形及指定工况的梁体真实线形。主梁的预制线形(... 针对传统顶推计算方法及顶推梁体拼装施工控制的不足,该文提出了一种基于非线性分析的顶推计算方法,可真实模拟顶推支墩不动、梁体前移的运行状态。该方法可直接给出梁体所有节段的拼装线形及指定工况的梁体真实线形。主梁的预制线形(即无应力线形)无需与滑道线形一致,两者不一致时,无需人工干预,主梁可自动适应滑道线形。针对背景工程进行全过程有限元建模计算,计算结果表明:该方法可直接给出梁体精确的理论拼装线形;顶推支墩支反力状态与主梁应力状态相关联,各支墩顶面标高调整仅影响当前墩及相邻墩的支反力;滑道线形可初步拟定为桥梁设计线形,根据支墩支反力及梁体应力变化曲线优化滑道线形即可满足顶推控制需求。 展开更多
关键词 顶推施工 非线性计算 无应力线形 拼装线形 滑道线形优化
暂未订购 下载PDF
已选0条
引用分析
参考文献
引证文献
 统计分析
检索结果
已选文献
上一页 1 2 … 250 下一页 到第 页
在线咨询 使用帮助 返回顶部 意见反馈