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DriftXMiner: A Resilient Process Intelligence Approach for Safe and Transparent Detection of Incremental Concept Drift in Process Mining
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作者 Puneetha B.H Manoj Kumar M.V +1 位作者 Prashanth B.S. Piyush Kumar Pareek 《Computers, Materials & Continua》 2026年第1期1086-1118,共33页
Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental con... Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental concept drift,gradually alter the behavior or structure of processes,making their detection and localization a challenging task.Traditional process mining techniques frequently assume process stationarity and are limited in their ability to detect such drift,particularly from a control-flow perspective.The objective of this research is to develop an interpretable and robust framework capable of detecting and localizing incremental concept drift in event logs,with a specific emphasis on the structural evolution of control-flow semantics in processes.We propose DriftXMiner,a control-flow-aware hybrid framework that combines statistical,machine learning,and process model analysis techniques.The approach comprises three key components:(1)Cumulative Drift Scanner that tracks directional statistical deviations to detect early drift signals;(2)a Temporal Clustering and Drift-Aware Forest Ensemble(DAFE)to capture distributional and classification-level changes in process behavior;and(3)Petri net-based process model reconstruction,which enables the precise localization of structural drift using transition deviation metrics and replay fitness scores.Experimental validation on the BPI Challenge 2017 event log demonstrates that DriftXMiner effectively identifies and localizes gradual and incremental process drift over time.The framework achieves a detection accuracy of 92.5%,a localization precision of 90.3%,and an F1-score of 0.91,outperforming competitive baselines such as CUSUM+Histograms and ADWIN+Alpha Miner.Visual analyses further confirm that identified drift points align with transitions in control-flow models and behavioral cluster structures.DriftXMiner offers a novel and interpretable solution for incremental concept drift detection and localization in dynamic,process-aware systems.By integrating statistical signal accumulation,temporal behavior profiling,and structural process mining,the framework enables finegrained drift explanation and supports adaptive process intelligence in evolving environments.Its modular architecture supports extension to streaming data and real-time monitoring contexts. 展开更多
关键词 Process mining concept drift gradual drift incremental drift clustering ensemble techniques process model event log
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A digital quartz resonant accelerometer with low temperature drift
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作者 CHEN Fubin ZHANG Haoyu +1 位作者 YANG Min ZHU Jialin 《中国惯性技术学报》 北大核心 2025年第3期273-278,共6页
In order to suppress the influence of temperature changes on the performance of accelerometers,a digital quartz resonant accelerometer with low temperature drift is developed using a quartz resonator cluster as a tran... In order to suppress the influence of temperature changes on the performance of accelerometers,a digital quartz resonant accelerometer with low temperature drift is developed using a quartz resonator cluster as a transducer element.In addition,a digital intellectual property(IP) is designed in FPGA to achieve signal processing and fusion of integrated resonators.A testing system for digital quartz resonant accelerometers is established to characterize the performance under different conditions.The scale factor of the accelerometer prototype reaches 3561.63 Hz/g in the range of -1 g to +1 g,and 3542.5 Hz/g in the range of-10 g to+10 g.In different measurement ranges,the linear correlation coefficient R~2 of the accelerometer achieves greater than 0.998.The temperature drift of the accelerometer prototype is tested using a constant temperature test chamber,with a temperature change from -20℃ to 80℃.After temperature-drift compensation,the zero bias temperature coefficient falls to 0.08 mg/℃,and the scale factor temperature coefficient is 65.43 ppm/℃.The experimental results show that the digital quartz resonant accelerometer exhibits excellent sensitivity and low temperature drift. 展开更多
关键词 quartz resonant accelerometer temperature drift scale factor signal fusion
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DRIFTS与随钻地层孔隙压力监测协同耦合的复杂超压判别方法
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作者 邱万军 胡益涛 印森林 《录井工程》 2025年第3期58-64,共7页
针对传统地层孔隙压力监测方法在生烃增压作用较强地层中存在的不足,提出一种基于地层孔隙压力监测技术与漫反射红外傅里叶变换光谱(DRIFTS)技术协同耦合的新型地层压力趋势判别方法。在随钻地层压力监测过程中,利用测录井参数(如dc指... 针对传统地层孔隙压力监测方法在生烃增压作用较强地层中存在的不足,提出一种基于地层孔隙压力监测技术与漫反射红外傅里叶变换光谱(DRIFTS)技术协同耦合的新型地层压力趋势判别方法。在随钻地层压力监测过程中,利用测录井参数(如dc指数、声波时差、电阻率等)偏离正常趋势线的特征识别异常压力地层,同时引入DRIFTS技术快速分析岩屑样品的矿物成分、总有机碳含量(TOC)及镜质体反射率(R_(o)),揭示有机质生烃增压效应。以珠江口盆地文昌A凹陷B井为例,通过地层压力技术与DRIFTS技术的协同耦合构建图板,进而识别出该井4350 m为生烃增压拐点,发现地层孔隙压力上升趋势与TOC、R_(o)的升高趋势高度一致,验证了协同判别方法的有效性。与传统模型相比,该方法能够同时量化欠压实与生烃作用的超压贡献,显著提高了复杂超压机制地层的压力判别精度。DRIFTS技术对矿物与有机质的高分辨率分析能力,与随钻压力监测数据的动态结合,为钻井工程提供了更可靠的地层压力预测与安全指导,具有重要现场应用价值。 展开更多
关键词 地层压力 随钻监测技术 driftS 技术 协同耦合 生烃增压 珠江口盆地
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N⁃DD: New Approach for Drift Detection Based on Neutrosophic Support Vector Machine
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作者 Rania Lutfi 《Journal of Harbin Institute of Technology(New Series)》 2025年第3期82-90,共9页
Many real⁃world machine learning applications face the challenge of dealing with changing data over time,known as concept drift,and the issue of data indeterminacy,where all the true labels available are unrealistic.T... Many real⁃world machine learning applications face the challenge of dealing with changing data over time,known as concept drift,and the issue of data indeterminacy,where all the true labels available are unrealistic.This can lead to a decrease in the accuracy of the prediction models.The aim of this study is to introduce a new approach for detecting drift,which is based on neutrosophic set theory.This approach takes into account uncertainty in the prediction model and is able to handle indeterminate information,considering its impact on the models performance.The proposed method reads data into windows and calculates a set of values based on the concept of neutrosophic membership.These values are then used in the Neutrosophic Support Vector Machine(N⁃SVM).To address the issue of indeterminate true label data,the values issued by N⁃SVM are expressed as entropy and used as input for the ADWIN(Adaptive Windowing)change detector.When a drift is detected,the prediction model is retrained by including only the most recent instances with the original training data set.The proposed method gives promising results in terms of drift detection accuracy compared to the state of existing drift detection methods such as KSWIN,ADWIN,and DWM. 展开更多
关键词 drift detection indeterminate labels UNCERTAINTY neutrosophic set theory data stream
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INEQUALITIES FOR EIGENVALUES OF POLYNOMIAL OPERATOR OF THE DRIFTING LAPLACIAN ON THE CIGAR SOLITON
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作者 YUAN Yuan SUN He-jun 《数学杂志》 2025年第4期293-306,共14页
In this paper,we investigate the weighted Dirichlet eigenvalue problem of polynomial operator of the drifting Laplacian on the cigar soliton■as follows■where is a positive continuous function on,denotes the outward ... In this paper,we investigate the weighted Dirichlet eigenvalue problem of polynomial operator of the drifting Laplacian on the cigar soliton■as follows■where is a positive continuous function on,denotes the outward unit normal to the boundary,and are two nonnegative constants.We establish some universal inequalities for eigenvalues of this problem. 展开更多
关键词 drifting Laplacian Cigarsoliton EIGENVALUE
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Cluster counting algorithm for the CEPC drift chamber using LSTM and DGCNN
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作者 Zhe-Fei Tian Guang Zhao +7 位作者 Ling-Hui Wu Zhen-Yu Zhang Xiang Zhou Shui-Ting Xin Shuai-Yi Liu Gang Li Ming-Yi Dong Sheng-Sen Sun 《Nuclear Science and Techniques》 2025年第7期14-23,共10页
The particle identification(PID)of hadrons plays a crucial role in particle physics experiments,especially in flavor physics and jet tagging.The cluster counting method,which measures the number of primary ionizations... The particle identification(PID)of hadrons plays a crucial role in particle physics experiments,especially in flavor physics and jet tagging.The cluster counting method,which measures the number of primary ionizations in gaseous detectors,is a promising breakthrough in PID.However,developing an effective reconstruction algorithm for cluster counting remains challenging.To address this challenge,we propose a cluster counting algorithm based on long short-term memory and dynamic graph convolutional neural networks for the CEPC drift chamber.Experiments on Monte Carlo simulated samples demonstrate that our machine learning-based algorithm surpasses traditional methods.It improves the K/πseparation of PID by 10%,meeting the PID requirements of CEPC. 展开更多
关键词 Particle identification Cluster counting Machine learning drift chamber
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Leveraging Safe and Secure AI for Predictive Maintenance of Mechanical Devices Using Incremental Learning and Drift Detection
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作者 Prashanth B.S Manoj Kumar M.V. +1 位作者 Nasser Almuraqab Puneetha B.H 《Computers, Materials & Continua》 2025年第6期4979-4998,共20页
Ever since the research in machine learning gained traction in recent years,it has been employed to address challenges in a wide variety of domains,including mechanical devices.Most of the machine learning models are ... Ever since the research in machine learning gained traction in recent years,it has been employed to address challenges in a wide variety of domains,including mechanical devices.Most of the machine learning models are built on the assumption of a static learning environment,but in practical situations,the data generated by the process is dynamic.This evolution of the data is termed concept drift.This research paper presents an approach for predictingmechanical failure in real-time using incremental learning based on the statistically calculated parameters of mechanical equipment.The method proposed here is applicable to allmechanical devices that are susceptible to failure or operational degradation.The proposed method in this paper is equipped with the capacity to detect the drift in data generation and adaptation.The proposed approach evaluates the machine learning and deep learning models for their efficacy in handling the errors related to industrial machines due to their dynamic nature.It is observed that,in the settings without concept drift in the data,methods like SVM and Random Forest performed better compared to deep neural networks.However,this resulted in poor sensitivity for the smallest drift in the machine data reported as a drift.In this perspective,DNN generated the stable drift detection method;it reported an accuracy of 84%and an AUC of 0.87 while detecting only a single drift point,indicating the stability to performbetter in detecting and adapting to new data in the drifting environments under industrial measurement settings. 展开更多
关键词 Incremental learning drift detection real-time failure prediction deep neural network proactive machine health monitoring
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A Fine-Grained Defect Prediction Method Based on Drift-Immune Graph Neural Networks
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作者 Fengyu Yang Fa Zhong +1 位作者 Xiaohui Wei Guangdong Zeng 《Computers, Materials & Continua》 2025年第2期3563-3590,共28页
The primary goal of software defect prediction (SDP) is to pinpoint code modules that are likely to contain defects, thereby enabling software quality assurance teams to strategically allocate their resources and manp... The primary goal of software defect prediction (SDP) is to pinpoint code modules that are likely to contain defects, thereby enabling software quality assurance teams to strategically allocate their resources and manpower. Within-project defect prediction (WPDP) is a widely used method in SDP. Despite various improvements, current methods still face challenges such as coarse-grained prediction and ineffective handling of data drift due to differences in project distribution. To address these issues, we propose a fine-grained SDP method called DIDP (drift-immune defect prediction), based on drift-immune graph neural networks (DI-GNN). DIDP converts source code into graph representations and uses DI-GNN to mitigate data drift at the model level. It also analyses key statements leading to file defects for a more detailed SDP approach. We evaluated the performance of DIDP in WPDP by examining its file-level and statement-level accuracy compared to state-of-the-art methods, and by examining its cross-project prediction accuracy. The results of the experiment show that DIDP showed significant improvements in F1-score and Recall@Top20%LOC compared to existing methods, even with large software version changes. DIDP also performed well in cross-project SDP. Our study demonstrates that DIDP achieves impressive prediction results in WPDP, effectively mitigating data drift and accurately predicting defective files. Additionally, DIDP can rank the risk of statements in defective files, aiding developers and testers in identifying potential code issues. 展开更多
关键词 Software defect prediction data drift graph neural networks information bottleneck
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Dynamic domain analysis for predicting concept drift in engineering AI-enabled software
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作者 Murtuza Shahzad Hamed Barzamini +2 位作者 Joseph Wilson Hamed Alhoori Mona Rahimi 《Journal of Data and Information Science》 2025年第2期124-151,共28页
Purpose:This research addresses the challenge of concept drift in AI-enabled software,particularly within autonomous vehicle systems where concept drift in object recognition(like pedestrian detection)can lead to misc... Purpose:This research addresses the challenge of concept drift in AI-enabled software,particularly within autonomous vehicle systems where concept drift in object recognition(like pedestrian detection)can lead to misclassifications and safety risks.This study introduces a proactive framework to detect early signs of domain-specific concept drift by leveraging domain analysis and natural language processing techniques.This method is designed to help maintain the relevance of domain knowledge and prevent potential failures in AI systems due to evolving concept definitions.Design/methodology/approach:The proposed framework integrates natural language processing and image analysis to continuously update and monitor key domain concepts against evolving external data sources,such as social media and news.By identifying terms and features closely associated with core concepts,the system anticipates and flags significant changes.This was tested in the automotive domain on the pedestrian concept,where the framework was evaluated for its capacity to detect shifts in the recognition of pedestrians,particularly during events like Halloween and specific car accidents.Findings:The framework demonstrated an ability to detect shifts in the domain concept of pedestrians,as evidenced by contextual changes around major events.While it successfully identified pedestrian-related drift,the system’s accuracy varied when overlapping with larger social events.The results indicate the model’s potential to foresee relevant shifts before they impact autonomous systems,although further refinement is needed to handle high-impact concurrent events.Research limitations:This study focused on detecting concept drift in the pedestrian domain within autonomous vehicles,with results varying across domains.To assess generalizability,we tested the framework for airplane-related incidents and demonstrated adaptability.However,unpredictable events and data biases from social media and news may obscure domain-specific drifts.Further evaluation across diverse applications is needed to enhance robustness in evolving AI environments.Practical implications:The proactive detection of concept drift has significant implications for AI-driven domains,especially in safety-critical applications like autonomous driving.By identifying early signs of drift,this framework provides actionable insights for AI system updates,potentially reducing misclassification risks and enhancing public safety.Moreover,it enables timely interventions,reducing costly and labor-intensive retraining requirements by focusing only on the relevant aspects of evolving concepts.This method offers a streamlined approach for maintaining AI system performance in environments where domain knowledge rapidly changes.Originality/value:This study contributes a novel domain-agnostic framework that combines natural language processing with image analysis to predict concept drift early.This unique approach,which is focused on real-time data sources,offers an effective and scalable solution for addressing the evolving nature of domain-specific concepts in AI applications. 展开更多
关键词 AI-enable software system Concept drift detection Applied machine learning Autonomous vehicles Natural language processing
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A Real-Time Deep Learning Approach for Electrocardiogram-Based Cardiovascular Disease Prediction with Adaptive Drift Detection and Generative Feature Replay
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作者 Soumia Zertal Asma Saighi +2 位作者 Sofia Kouah Souham Meshoul Zakaria Laboudi 《Computer Modeling in Engineering & Sciences》 2025年第9期3737-3782,共46页
Cardiovascular diseases(CVDs)continue to present a leading cause ofmortalityworldwide,emphasizing the importance of early and accurate prediction.Electrocardiogram(ECG)signals,central to cardiac monitoring,have increa... Cardiovascular diseases(CVDs)continue to present a leading cause ofmortalityworldwide,emphasizing the importance of early and accurate prediction.Electrocardiogram(ECG)signals,central to cardiac monitoring,have increasingly been integratedwithDeep Learning(DL)for real-time prediction of CVDs.However,DL models are prone to performance degradation due to concept drift and to catastrophic forgetting.To address this issue,we propose a realtime CVDs prediction approach,referred to as ADWIN-GFR that combines Convolutional Neural Network(CNN)layers,for spatial feature extraction,with Gated Recurrent Units(GRU),for temporal modeling,alongside adaptive drift detection and mitigation mechanisms.The proposed approach integratesAdaptiveWindowing(ADWIN)for realtime concept drift detection,a fine-tuning strategy based on Generative Features Replay(GFR)to preserve previously acquired knowledge,and a dynamic replay buffer ensuring variance,diversity,and data distribution coverage.Extensive experiments conducted on the MIT-BIH arrhythmia dataset demonstrate that ADWIN-GFR outperforms standard fine-tuning techniques,achieving an average post-drift accuracy of 95.4%,amacro F1-score of 93.9%,and a remarkably low forgetting score of 0.9%.It also exhibits an average drift detection delay of 12 steps and achieves an adaptation gain of 17.2%.These findings underscore the potential of ADWIN-GFR for deployment in real-world cardiac monitoring systems,including wearable ECG devices and hospital-based patient monitoring platforms. 展开更多
关键词 Real-time cardiovascular disease prediction concept drift detection catastrophic forgetting fine-tuning electrocardiogram convolutional neural networks gated recurrent units adaptive windowing generative feature replay
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Beam test results of the prototype of the multi wire drift chamber for the CSR external-target experiment
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作者 Zhi Qin Zhou-Bo He +18 位作者 Zhe Cao Tao Chen Zhi Deng Li-Min Duan Dong Guo Rong-Jiang Hu Jie Kong Can-Wen Liu Peng Ma Tian-Lei Pu Yi Qian Xiang-Lun Wei Shi-Hai Wen Xiang-Jie Wen Jun-Wei Yan He-Run Yang Zuo-Qiao Yang Yu-Hong Yu Zhi-Gang Xiao 《Nuclear Science and Techniques》 2025年第4期171-180,共10页
A half-size prototype of the multi wire drift chamber for the cooling storage ring external-target experiment(CEE)was assembled and tested in the 350 MeV/u Kr+Fe reactions at the heavy-ion research facility in Lanzhou... A half-size prototype of the multi wire drift chamber for the cooling storage ring external-target experiment(CEE)was assembled and tested in the 350 MeV/u Kr+Fe reactions at the heavy-ion research facility in Lanzhou.The prototype consists of six sense layers,where the sense wires are stretched in three directions X,U,and V;meeting 0?,30?,and-30?,respectively,with respect to the vertical axis.The sensitive area of the prototype is 76 cm×76 cm.The amplified and shaped signals from the anode wires were digitized in a serial capacity array.When operating at a high voltage of 1500 V on the anode wires,the efficiency for each layer is greater than 95%.The tracking residual is approximately 301±2μm.This performance satisfies the requirements of CEE. 展开更多
关键词 Multi wire drift chamber(MWDC) CSR external-target experiment(CEE) Tracking
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Concept Drift Detection and Adaptation Method for IoT Security Framework
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作者 Yin Jie Xie Wenwei +2 位作者 Liang Guangjun Zhang Lanping Zhang Xixi 《China Communications》 2025年第12期137-147,共11页
With the gradual penetration of the internet of things(IoT)into all areas of life,the scale of IoT devices shows an explosive growth trend.The era of internet of everything is coming,and the important position of IoT ... With the gradual penetration of the internet of things(IoT)into all areas of life,the scale of IoT devices shows an explosive growth trend.The era of internet of everything is coming,and the important position of IoT security is becoming increasingly prominent.Due to the large number types of IoT devices,there may be different security vulnerabilities,and unknown attack forms and virus samples are appear.In other words,large number of IoT devices,large data volumes,and various attack forms pose a big challenge of malicious traffic identification.To solve these problems,this paper proposes a concept drift detection and adaptation(CDDA)method for IoT security framework.The AI model performance is evaluated by verifying the effectiveness of IoT traffic for data drift detection,so as to select the best AI model.The experimental test are given to confirm that the feasibility of the framework and the adaptive method in practice,and the effect on the performance of IoT traffic identification is also verified. 展开更多
关键词 concept drift detection and adaptive(CDDA)method IoT security malicious traffic identification
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目标解耦驱动的在线深度网络
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作者 郭虎升 申聪 +1 位作者 夏浩森 王文剑 《小型微型计算机系统》 北大核心 2026年第1期42-50,共9页
概念漂移是数据流挖掘中不可避免的难点问题,其典型特征是数据分布随时间可能发生改变.针对现有模型处理数据流分类任务时出现过拟合的问题,本文提出了一种目标解耦驱动的在线深度网络(Online Deep Network driven by Target Decoupling... 概念漂移是数据流挖掘中不可避免的难点问题,其典型特征是数据分布随时间可能发生改变.针对现有模型处理数据流分类任务时出现过拟合的问题,本文提出了一种目标解耦驱动的在线深度网络(Online Deep Network driven by Target Decoupling,ODNTD).首先,该模型从历史数据流中学习一个任务未知型特征提取器,实现了对任务的无偏见表示学习,从而增强了模型的泛化能力;其次,模型利用任务特定的权重调整,使得任务未知的通用特征表示能够适应具体任务,通过这种目标任务的权重学习进一步提升了模型的适应性.实验结果表明,所提出的方法对含概念漂移的数据流有良好的泛化性能. 展开更多
关键词 概念漂移 表示学习 权重学习 自适应深度网络 特征表示蒸馏
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端到端框架下基于LSTM与在线修正的适应性投资组合策略
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作者 刘悦 张永 +1 位作者 黎嘉豪 王晓辉 《系统管理学报》 北大核心 2026年第1期233-246,共14页
深度学习对长序列信息具有较强的记忆能力,并能有效建模复杂关系。本文采用多对多长短期记忆网络,研究端到端框架下的投资组合策略。首先,在端到端深度学习框架下,结合多对多长短期记忆神经网络与滑动窗口技术构建投资组合策略;其次,以... 深度学习对长序列信息具有较强的记忆能力,并能有效建模复杂关系。本文采用多对多长短期记忆网络,研究端到端框架下的投资组合策略。首先,在端到端深度学习框架下,结合多对多长短期记忆神经网络与滑动窗口技术构建投资组合策略;其次,以固定历史窗口的均匀定常再调整策略为基准,在线评估神经网络策略近期表现,并对其进行修正以缓解概念漂移问题;再次,集成多个历史窗口下的修正策略,形成稳健的投资组合策略;最后,基于国内外市场数据开展数值分析,结果表明,该策略在稳健性、收益性及交易费率敏感性方面均优于对比策略。 展开更多
关键词 投资组合 端到端学习 多对多长短期记忆网络 在线修正 概念漂移
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水平地震下RC剪力墙结构层间位移角限值评估
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作者 凌育洪 汤怀鼎 +1 位作者 周靖 温新贵 《工程力学》 北大核心 2026年第2期135-145,共11页
为评估现行规范水平地震作用下钢筋混凝土(RC)剪力墙结构层间位移角限值的合理性,与美国规范对比,构建50个RC剪力墙数值模型结构进行非线性分析,探讨场地类别、设防烈度和结构高度等因素对剪力墙层间位移角富裕度比值β_(C/A)的影响规... 为评估现行规范水平地震作用下钢筋混凝土(RC)剪力墙结构层间位移角限值的合理性,与美国规范对比,构建50个RC剪力墙数值模型结构进行非线性分析,探讨场地类别、设防烈度和结构高度等因素对剪力墙层间位移角富裕度比值β_(C/A)的影响规律。提出位移角限值建议值,逐步放松位移角,评估放松位移角后结构在罕遇地震下的安全性;用同样方法讨论广东省标准《高层建筑混凝土结构技术规程》放松位移角限值的合理性。结果表明:β_(C/A)值均大于1,表明我国规范中剪力墙结构层间位移角限值比美国规范严格;以建议值1/550作为层间位移角限值设计剪力墙结构是安全合理的,说明广东省标准《高层建筑混凝土结构技术规程》以1/180为中震作用下RC剪力墙结构弹性层间位移角限值具备合理性。 展开更多
关键词 层间位移角限值 剪力墙结构 中美规范对比 弹塑性分析 安全性评估
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我国中等职业教育的合法性危机与破解路径
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作者 张学敏 赵志章 《职业技术教育》 北大核心 2026年第1期5-12,共8页
我国中等职业教育面临显著的“合法性危机”,虽然通过法律明确其“类型教育”地位,通过财政投入持续加强支持力度,但中职仍被普遍视为“考不上普通高中学生”的“无奈选择”,国家政策支持与社会认可之间存在巨大鸿沟。为应对这一危机,... 我国中等职业教育面临显著的“合法性危机”,虽然通过法律明确其“类型教育”地位,通过财政投入持续加强支持力度,但中职仍被普遍视为“考不上普通高中学生”的“无奈选择”,国家政策支持与社会认可之间存在巨大鸿沟。为应对这一危机,中职学校出现“定位漂移”,即从“以就业为导向”转向“以升学为主导”。这虽短期内缓解了生源压力,却弱化了职教特色,偏离了服务产业发展的根本使命,反而加深了长期的身份模糊与价值危机。破解之道在于坚持中等职业教育的职业特色,分类施策,沿着“办精办强、转型发展、整合升格、结构性退出”四条路径进行功能重构与体系再造,通过结构性调整,重塑中职教育的不可替代性,从根本上实现其社会认同与可持续发展。 展开更多
关键词 中等职业教育 合法性危机 定位漂移 分类发展
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基于ANSYS的摆动轴漂移热误差消减设计研究
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作者 杨红军 李清耀 慕道增 《机床与液压》 北大核心 2026年第1期56-61,共6页
为解决五轴加工中心摆动回转轴因热变形引起的定位漂移问题,通过热误差分析与结构优化提升轴系精度稳定性。通过多种工况测试及ANSYS热-结构耦合有限元分析,确定定位漂移的根源在于冷却介质温度变化引起主轴周期性热变形。通过约束热变... 为解决五轴加工中心摆动回转轴因热变形引起的定位漂移问题,通过热误差分析与结构优化提升轴系精度稳定性。通过多种工况测试及ANSYS热-结构耦合有限元分析,确定定位漂移的根源在于冷却介质温度变化引起主轴周期性热变形。通过约束热变形及降低系统热变形内应力,重新设计多种编码器支撑结构,并利用ANSYS对新结构的热误差和灵敏度进行仿真分析,并采用最优结构方案进行实际应用验证。新摆动回转轴精度采用验棒和动态采样两种方式检测,结果表明:新结构使热漂移量从5.4″降至0.18″;实际测试中最小进给单位0.0001°(0.36″)下轴系响应灵敏无超调。改进后的回转轴定位稳定、灵敏度优良,漂移热误差问题得到解决,验证了分析与改进设计的有效性。 展开更多
关键词 摆动回转轴 漂移热误差 闭环控制 灵敏度 热-结构耦合分析
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基于视觉和控制技术的抗风高准度植保无人机设计
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作者 张一鸣 伍超 王琢 《仪表技术》 2026年第1期9-12,25,共5页
随着我国智慧农业的快速发展,植保无人机逐渐得到广泛应用并显著提升了农业生产效率。然而,当前多旋翼植保无人机在作业中仍普遍存在药液飘移严重、复杂气象条件下稳定性不足等问题。基于此,开发一种集成视觉技术、控制算法与先进飞控... 随着我国智慧农业的快速发展,植保无人机逐渐得到广泛应用并显著提升了农业生产效率。然而,当前多旋翼植保无人机在作业中仍普遍存在药液飘移严重、复杂气象条件下稳定性不足等问题。基于此,开发一种集成视觉技术、控制算法与先进飞控系统的智能化植保无人机平台。在四旋翼硬件设计中采用模块化架构,整合了飞控模块、风速风向传感器、树莓派、STM32单片机和舵机驱动喷口装置。飞控模块负责飞行控制与航线规划;三杯式风速传感器与风向传感器实时采集环境信息;树莓派搭载YOLOv5视觉系统识别作业目标,并将视觉信息与气象数据传送至STM32单片机;STM32对多源信息进行融合处理并调控舵机喷口角度,从而实现药液飘移的有效抑制。仿真结果表明,该系统在复杂风场环境下表现出良好的适应性,药液飘移显著降低,作业安全性高,可在4级风以下条件下实现精准喷洒,并在风速超过5级时自动中止作业,有效提升了植保无人机在复杂气象条件下的喷洒性能与可靠性。 展开更多
关键词 植保无人机 抗风 药液飘移 仿真
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Data Analysis and Modeling of Fiber Optic Gyroscope Drift 被引量:17
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作者 缪玲娟 张方生 +1 位作者 沈军 刘伟 《Journal of Beijing Institute of Technology》 EI CAS 2002年第1期50-55,共6页
A data gathering system is designed for the interferometric fiber optic gyroscope (IFOG) of land strapdown inertial system. IFOG is tested and the testing curve is given. The test data of IFOG are analyzed with Allan ... A data gathering system is designed for the interferometric fiber optic gyroscope (IFOG) of land strapdown inertial system. IFOG is tested and the testing curve is given. The test data of IFOG are analyzed with Allan variance method and each error coefficient is identified. Furthermore, a random drift error model for IFOG is built by the method of time series analysis. The conclusion provides supports for improving IFOG design and compensating for errors of IFOG in practice. 展开更多
关键词 fiber optic gyroscope random drift Allan variance MODELING
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SO_2在CaCO_3颗粒表面转化的DRIFTS研究 被引量:17
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作者 李雷 陈忠明 +2 位作者 丁杰 朱彤 张远航 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2004年第12期1556-1559,共4页
碳酸钙 (CaCO3 )是大气中矿物颗粒物的重要组分 ,其非均相大气化学行为很不清楚。利用原位漫反射红外傅里叶变换光谱 (DiffuseReflectanceInfraredFourierTransformSpectroscopy ,DRIFTS)研究了二氧化硫(SO2 )在CaCO3 颗粒物表面的转化... 碳酸钙 (CaCO3 )是大气中矿物颗粒物的重要组分 ,其非均相大气化学行为很不清楚。利用原位漫反射红外傅里叶变换光谱 (DiffuseReflectanceInfraredFourierTransformSpectroscopy ,DRIFTS)研究了二氧化硫(SO2 )在CaCO3 颗粒物表面的转化情况。通过比较不同条件下 ,亚硫酸盐和硫酸盐的原位光谱 ,探讨了SO2在CaCO3 表面氧化中臭氧 (O3 )所起的作用。结果表明 ,利用DRIFTS原位分析反应器研究CaCO3 表面硫酸盐的生成是可行的。在存在O3 条件下 ,SO2 在CaCO3 表面能够被氧化成硫酸盐 ,反应分为吸附和氧化两个步骤进行。 展开更多
关键词 CACO3 颗粒表面 非均相 矿物颗粒 二氧化硫(SO2) 碳酸钙 反应器 SO2 硫酸盐 颗粒物
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