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Conditional Generative Adversarial Network-Based Travel Route Recommendation
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作者 Sunbin Shin Luong Vuong Nguyen +3 位作者 Grzegorz J.Nalepa Paulo Novais Xuan Hau Pham Jason J.Jung 《Computers, Materials & Continua》 2026年第1期1178-1217,共40页
Recommending personalized travel routes from sparse,implicit feedback poses a significant challenge,as conventional systems often struggle with information overload and fail to capture the complex,sequential nature of... Recommending personalized travel routes from sparse,implicit feedback poses a significant challenge,as conventional systems often struggle with information overload and fail to capture the complex,sequential nature of user preferences.To address this,we propose a Conditional Generative Adversarial Network(CGAN)that generates diverse and highly relevant itineraries.Our approach begins by constructing a conditional vector that encapsulates a user’s profile.This vector uniquely fuses embeddings from a Heterogeneous Information Network(HIN)to model complex user-place-route relationships,a Recurrent Neural Network(RNN)to capture sequential path dynamics,and Neural Collaborative Filtering(NCF)to incorporate collaborative signals from the wider user base.This comprehensive condition,further enhanced with features representing user interaction confidence and uncertainty,steers a CGAN stabilized by spectral normalization to generate high-fidelity latent route representations,effectively mitigating the data sparsity problem.Recommendations are then formulated using an Anchor-and-Expand algorithm,which selects relevant starting Points of Interest(POI)based on user history,then expands routes through latent similarity matching and geographic coherence optimization,culminating in Traveling Salesman Problem(TSP)-based route optimization for practical travel distances.Experiments on a real-world check-in dataset validate our model’s unique generative capability,achieving F1 scores ranging from 0.163 to 0.305,and near-zero pairs−F1 scores between 0.002 and 0.022.These results confirm the model’s success in generating novel travel routes by recommending new locations and sequences rather than replicating users’past itineraries.This work provides a robust solution for personalized travel planning,capable of generating novel and compelling routes for both new and existing users by learning from collective travel intelligence. 展开更多
关键词 Travel route recommendation conditional generative adversarial network heterogeneous information network anchor-and-expand algorithm
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Probabilistic Site Investigation Optimization of Gassy Soils Based on Conditional Random Field and Monte Carlo Simulation
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作者 Shaolin Ding 《World Journal of Engineering and Technology》 2025年第1期1-11,共11页
Gassy soils are distributed in relatively shallow layers the Quaternary deposit in Hangzhou Bay area. The shallow gassy soils significantly affect the construction of underground projects. Proper characterization of s... Gassy soils are distributed in relatively shallow layers the Quaternary deposit in Hangzhou Bay area. The shallow gassy soils significantly affect the construction of underground projects. Proper characterization of spatial distribution of shallow gassy soils is indispensable prior to construction of underground projects in the area. Due to the costly conditions required in the site investigation for gassy soils, only a limited number of gas pressure data can be obtained in engineering practice, which leads to the uncertainty in characterizing spatial distribution of gassy soils. Determining the number of boreholes for investigating gassy soils and their corresponding locations is pivotal to reducing construction risk induced by gassy soils. However, this primarily relies on the engineering experience in the current site investigation practice. This study develops a probabilistic site investigation optimization method for planning investigation schemes (including the number and locations of boreholes) of gassy soils based on the conditional random field and Monte Carlo simulation. The proposed method aims to provide an optimal investigation scheme before the site investigation based on prior knowledge. Finally, the proposed approach is illustrated using a case study. 展开更多
关键词 Gassy Soils Site Investigation UNCERTAINTY conditional Random Field Monte Carlo Simulation
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A FORMULA OF CONDITIONAL ENTROPY FOR METRICS INDUCED BY PROBABILITY BI-SEQUENCES
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作者 M.RAHIMI N.BIDABADI 《Acta Mathematica Scientia》 2025年第4期1619-1639,共21页
We study the conditional entropy of topological dynamical systems using a family of metrics induced by probability bi-sequences.We present a Brin-Katok formula by replacing the mean metric by a family of metrics induc... We study the conditional entropy of topological dynamical systems using a family of metrics induced by probability bi-sequences.We present a Brin-Katok formula by replacing the mean metric by a family of metrics induced by a probability bi-sequence.We also establish the Katok’s entropy formula for conditional entropy for ergodic measures in the case of the new family of metrics. 展开更多
关键词 ENTROPY conditional entropy probability bi-sequence
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Cross‑sectional anomalies and conditional asset pricing models based on investor sentiment: evidence from the Chinese stock market
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作者 Zhong‑Qiang Zhou Jiajia Wu +1 位作者 Ping Huang Xiong Xiong 《Financial Innovation》 2025年第1期2984-3007,共24页
This study examines a comprehensive set of 30 cross-sectional anomalies in the Chinese A-share market to investigate whether incorporating investor sentiment as conditioning information enhances the explanatory power ... This study examines a comprehensive set of 30 cross-sectional anomalies in the Chinese A-share market to investigate whether incorporating investor sentiment as conditioning information enhances the explanatory power of asset pricing models.Utilizing a long–short portfolio strategy and Fama–MacBeth cross-sectional regression,we find that trading-based anomalies outnumber accounting-based anomalies in the Chinese market.Our results demonstrate that conditional models significantly outperform their unconditional counterparts.Notably,investor sentiment is crucial for capturing the size anomaly when excluding observations from the COVID-19 pandemic period.Additionally,it substantially improves the ability of conditional Fama–French three-factor models to capture individual anomalies and enhances the return–prediction accuracy of conditional CAPMs.We suggest further investigating high-frequency investor sentiment-based conditional models to anticipate stock price fluctuations during extraordinary public health events. 展开更多
关键词 Cross-sectional anomalies conditional asset pricing Investor sentiment
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Weighted Attribute Based Conditional Proxy Re-Encryption in the Cloud
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作者 Xixi Yan Jing Zhang Pengyu Cheng 《Computers, Materials & Continua》 2025年第4期1399-1414,共16页
Conditional proxy re-encryption(CPRE)is an effective cryptographic primitive language that enhances the access control mechanism and makes the delegation of decryption permissions more granular,but most of the attribu... Conditional proxy re-encryption(CPRE)is an effective cryptographic primitive language that enhances the access control mechanism and makes the delegation of decryption permissions more granular,but most of the attribute-based conditional proxy re-encryption(AB-CPRE)schemes proposed so far do not take into account the importance of user attributes.A weighted attribute-based conditional proxy re-encryption(WAB-CPRE)scheme is thus designed to provide more precise decryption rights delegation.By introducing the concept of weight attributes,the quantity of system attributes managed by the server is reduced greatly.At the same time,a weighted tree structure is constructed to simplify the expression of access structure effectively.With conditional proxy re-encryption,large amounts of data and complex computations are outsourced to cloud servers,so the data owner(DO)can revoke the user’s decryption rights directly with minimal costs.The scheme proposed achieves security against chosen plaintext attacks(CPA).Experimental simulation results demonstrated that the decryption time is within 6–9 ms,and it has a significant reduction in communication and computation cost on the user side with better functionality compared to other related schemes,which enables users to access cloud data on devices with limited resources. 展开更多
关键词 Cloud service conditional proxy re-encryption user revocation weighted attribute
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FedCLCC:A personalized federated learning algorithm for edge cloud collaboration based on contrastive learning and conditional computing
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作者 Kangning Yin Xinhui Ji +1 位作者 Yan Wang Zhiguo Wang 《Defence Technology(防务技术)》 2025年第1期80-93,共14页
Federated learning(FL)is a distributed machine learning paradigm for edge cloud computing.FL can facilitate data-driven decision-making in tactical scenarios,effectively addressing both data volume and infrastructure ... Federated learning(FL)is a distributed machine learning paradigm for edge cloud computing.FL can facilitate data-driven decision-making in tactical scenarios,effectively addressing both data volume and infrastructure challenges in edge environments.However,the diversity of clients in edge cloud computing presents significant challenges for FL.Personalized federated learning(pFL)received considerable attention in recent years.One example of pFL involves exploiting the global and local information in the local model.Current pFL algorithms experience limitations such as slow convergence speed,catastrophic forgetting,and poor performance in complex tasks,which still have significant shortcomings compared to the centralized learning.To achieve high pFL performance,we propose FedCLCC:Federated Contrastive Learning and Conditional Computing.The core of FedCLCC is the use of contrastive learning and conditional computing.Contrastive learning determines the feature representation similarity to adjust the local model.Conditional computing separates the global and local information and feeds it to their corresponding heads for global and local handling.Our comprehensive experiments demonstrate that FedCLCC outperforms other state-of-the-art FL algorithms. 展开更多
关键词 Federated learning Statistical heterogeneity Personalized model conditional computing Contrastive learning
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Neural correlates of conditional reasoning dysfunction in major depression:An event-related potential study with the Wason selection task
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作者 Jia-Xv Li Mei-Chen Lu +7 位作者 Luo-An Wu Wei Li Yu Li Xin-Ping Li Xiao-Hong Liu Xue-Zheng Gao Zhen-He Zhou Hong-Liang Zhou 《World Journal of Psychiatry》 2025年第12期107-119,共13页
BACKGROUND Patients with major depression(MD)exhibit conditional reasoning dysfunction;however,no studies on the event-related potential(ERP)characteristics of conditional reasoning in MD have been reported.AIM To inv... BACKGROUND Patients with major depression(MD)exhibit conditional reasoning dysfunction;however,no studies on the event-related potential(ERP)characteristics of conditional reasoning in MD have been reported.AIM To investigate the ERP characteristics of conditional reasoning in MD patients and explore the neural mechanism of cognitive processing.METHODS Thirty-four patients with MD and 34 healthy controls(HCs)completed ERP measurements while performing the Wason selection task(WST).The clusterbased permutation test in FieldTrip was used to compare the differences in the mean amplitudes between the patients with MD and HCs on the ERP components under different experimental conditions.Behavioral data[accuracy(ACC)and reaction times(RTs)],the ERP P100 and late positive potentials(LPPs)were analyzed.RESULTS Although the mean ACC was greater and the mean of RTs was shorter in HCs than in MD patients,the differences were not statistically significant.However,across both groups,the ACC in the precautionary WST was greater than that in the other tasks,and the RTs in the abstract task were greater than those in the other tasks.Importantly,compared with that of HCs,the P100 of the left centroparietal sites was significantly increased,and the early LPP was attenuated at parietal sites and increased at left frontocentral sites;the medium LPP and late LPP were increased at the left frontocentral sites.CONCLUSION Patients with MD have conditional reasoning dysfunction and exhibit abnormal ERP characteristics evoked by the WST,which suggests neural correlates of abnormalities in conditional reasoning function in MD patients. 展开更多
关键词 Major depression Event-related potential Wason selection task conditional reasoning Neural mechanism
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An Extension of Conditional Nonlinear Optimal Perturbation in the Time Dimension and Its Applications in Targeted Observations
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作者 Ziqing ZU Mu MU +1 位作者 Jiangjiang XIA Qiang WANG 《Advances in Atmospheric Sciences》 2025年第9期1783-1797,共15页
The Conditional Nonlinear Optimal Perturbation(CNOP)method works essentially for conventional numerical models;however,it is not fully applicable to the commonly used deep-learning forecasting models(DLMs),which typic... The Conditional Nonlinear Optimal Perturbation(CNOP)method works essentially for conventional numerical models;however,it is not fully applicable to the commonly used deep-learning forecasting models(DLMs),which typically input multiple time slices without deterministic dependencies.In this study,the CNOP for DLMs(CNOP-DL)is proposed as an extension of the CNOP in the time dimension.This method is useful for targeted observations as it indicates not only where but also when to deploy additional observations.The CNOP-DL is calculated for a forecast case of sea surface temperature in the South China Sea with a DLM.The CNOP-DL identifies a sensitive area northwest of Palawan Island at the last input time.Sensitivity experiments demonstrate that the sensitive area identified by the CNOP-DL is effective not only for the CNOP-DL itself,but also for random perturbations.Therefore,this approach holds potential for guiding practical field campaigns.Notably,forecast errors are more sensitive to time than to location in the sensitive area.It highlights the crucial role of identifying the time of the sensitive area in targeted observations,corroborating the usefulness of extending the CNOP in the time dimension. 展开更多
关键词 deep-learning forecasting model conditional nonlinear optimal perturbation targeted observation sensitive area
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Two Causal-Modeling Approaches to Indicative Conditionals
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作者 ChingHui Su 《逻辑学研究》 2025年第6期43-61,共19页
Recently there have been two causal modelling approaches to indicative conditionals,i.e.extrapolationist(Deng&Lee,2021)and filterist(Liang&Wang,2022),although they all take an interventionist position on subju... Recently there have been two causal modelling approaches to indicative conditionals,i.e.extrapolationist(Deng&Lee,2021)and filterist(Liang&Wang,2022),although they all take an interventionist position on subjunctive conditionals.Motivated by the so-called OK pairs,they try to provide a convincing explanation of the intuition underlying the OK pairs.As far as we know,what they have done is to provide not only an explanation of the OK pairs,but also a way of distinguishing between indicative and subjunctive conditionals.Although we agree with their success in explaining the OK pairs within a causal modelling framework,we argue that their ways of distinguishing between indicative and subjunctive conditionals fail.Instead,we argue that their approaches can be used to distinguish between two readings of conditionals,the epistemic reading and the ontic reading.which can be applied to both indicative and subjunctive conditionals.We conclude by arguing that these two readings are related to two approaches to asking and answering causal questions:the“auses-of-effects"approach and the"effects-of-causes"approach. 展开更多
关键词 subjunctive conditionals extrapolationist causal modelling approaches epistemic reading causal modeling filterist indicative subjunctive con ok pairs
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Optimal Receiver Operating Characteristic Curve of Classical Conditional Power under Normal Models
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作者 ZHANG Ying-Ying 《应用概率统计》 北大核心 2025年第2期277-304,共28页
A Receiver Operating Characteristic(ROC)analysis of a power is important and useful in clinical trials.A Classical Conditional Power(CCP)is a probability of a classical rejection region given values of true treatment ... A Receiver Operating Characteristic(ROC)analysis of a power is important and useful in clinical trials.A Classical Conditional Power(CCP)is a probability of a classical rejection region given values of true treatment effect and interim result.For hypotheses and reversed hypotheses under normal models,we obtain analytical expressions of the ROC curves of the CCP,find optimal ROC curves of the CCP,investigate the superiority of the ROC curves of the CCP,calculate critical values of the False Positive Rate(FPR),True Positive Rate(TPR),and cutoff of the optimal CCP,and give go/no go decisions at the interim of the optimal CCP.In addition,extensive numerical experiments are carried out to exemplify our theoretical results.Finally,a real data example is performed to illustrate the go/no go decisions of the optimal CCP. 展开更多
关键词 area under the curve(AUC) classical conditional power(CCP) go/no go decisions historical and interim data receiver operating characteristic(ROC)curve
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The evolving distribution of humidity conditional on temperature and implications for compound heat extremes across China in a warming world
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作者 Caixia Liang Jiacan Yuan 《Atmospheric and Oceanic Science Letters》 2025年第6期9-14,共6页
The likelihood of extreme heat occurrence is continuously increasing with global warming.Under high temperatures,humidity may exacerbate the heat impact on humanity.As atmospheric humidity depends on moisture availabi... The likelihood of extreme heat occurrence is continuously increasing with global warming.Under high temperatures,humidity may exacerbate the heat impact on humanity.As atmospheric humidity depends on moisture availability and is constrained by air temperature,it is important to project the changes in the distribution of atmospheric humidity conditional on air temperature as the climate continuously warms.Here,a non-crossing quantile smoothing spline is employed to build quantile regression models emulating conditional distributions of dew point(a measure of humidity)on local temperature evolving with escalating global mean surface temperature.By applying these models to 297 weather stations in seven regions in China,the study analyzes historical trends of humid-heat and dry-hot days,and projects their changes under global warming of 2.0℃ and 4.5℃.In response to global warming,rising trends of humid-heat extremes,while weakening trends of dry-hot extremes,are observed at most stations in Northeast China.Additionally,results indicate an increasing trend in dry-hot extremes at numerous stations across central China,but a rise in humid-heat extremes over Northwest China and coastal regions.These trends found in the current climate state are projected to intensify under 2.0℃ and 4.5℃ warming,possibly influenced by the heterogeneous variations in precipitation,soil moisture,and water vapor fluxes.Requiring much lower computational resources than coupled climate models,these quantile regression models can further project compound humidity and temperature extremes in response to different levels of global warming,potentially informing the risk management of compound humid-heat extremes on a local scale. 展开更多
关键词 Global warming conditional distribution of dew point on temperature Non-crossing quantile smoothing spline model Compound heat extremes
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Wavelet Transform-Based Bayesian Inference Learning with Conditional Variational Autoencoder for Mitigating Injection Attack in 6G Edge Network
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作者 Binu Sudhakaran Pillai Raghavendra Kulkarni +1 位作者 Venkata Satya Suresh kumar Kondeti Surendran Rajendran 《Computer Modeling in Engineering & Sciences》 2025年第10期1141-1166,共26页
Future 6G communications will open up opportunities for innovative applications,including Cyber-Physical Systems,edge computing,supporting Industry 5.0,and digital agriculture.While automation is creating efficiencies... Future 6G communications will open up opportunities for innovative applications,including Cyber-Physical Systems,edge computing,supporting Industry 5.0,and digital agriculture.While automation is creating efficiencies,it can also create new cyber threats,such as vulnerabilities in trust and malicious node injection.Denialof-Service(DoS)attacks can stop many forms of operations by overwhelming networks and systems with data noise.Current anomaly detection methods require extensive software changes and only detect static threats.Data collection is important for being accurate,but it is often a slow,tedious,and sometimes inefficient process.This paper proposes a new wavelet transformassisted Bayesian deep learning based probabilistic(WT-BDLP)approach tomitigate malicious data injection attacks in 6G edge networks.The proposed approach combines outlier detection based on a Bayesian learning conditional variational autoencoder(Bay-LCVariAE)and traffic pattern analysis based on continuous wavelet transform(CWT).The Bay-LCVariAE framework allows for probabilistic modelling of generative features to facilitate capturing how features of interest change over time,spatially,and for recognition of anomalies.Similarly,CWT allows emphasizing the multi-resolution spectral analysis and permits temporally relevant frequency pattern recognition.Experimental testing showed that the flexibility of the Bayesian probabilistic framework offers a vast improvement in anomaly detection accuracy over existing methods,with a maximum accuracy of 98.21%recognizing anomalies. 展开更多
关键词 Bayesian inference learning automaton convolutional wavelet transform conditional variational autoencoder malicious data injection attack edge environment 6G communication
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方向性海洋环境设计条件的确定和应用
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作者 李晔 李林斌 +1 位作者 位巍 韦斯俊 《船舶力学》 北大核心 2026年第2期271-281,共11页
考虑到海洋环境条件分布的方向性差异,在不降低海工结构可靠度的前提下,结构设计可采用方向性设计条件。与全方向设计条件相比,方向性设计条件通过重新分配各方向上的超越概率,来达到优化结构设计的目的。满足规范可靠度目标要求的方向... 考虑到海洋环境条件分布的方向性差异,在不降低海工结构可靠度的前提下,结构设计可采用方向性设计条件。与全方向设计条件相比,方向性设计条件通过重新分配各方向上的超越概率,来达到优化结构设计的目的。满足规范可靠度目标要求的方向性设计条件可采用本文提出的迭代方法确定,并针对具体结构进行设计分析和比较,以确定最优结构设计方案及其对应的最优方向性设计条件。分布拟合和大幅外推所带来的统计不确定性影响需要充分考虑,而采用本文提出的“组合法”来获得方向性环境要素分布是降低统计不确定性影响的有效途径。 展开更多
关键词 方向性设计条件 全方向设计条件 结构可靠度 年超越概率
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定量评估气象条件对滇池蓝藻水华发生的影响及预测
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作者 徐虹 戴丛蕊 +2 位作者 何雨芩 程晋昕 王玉尤婷 《水生态学杂志》 北大核心 2026年第2期89-96,共8页
对滇池蓝藻水华发生的可能性进行预测,为预防和开展藻华防治、保护水环境提供科学依据。基于2001―2021年逐日MODIS数据和随机森林算法,分别构建复苏期(3―6月)和高发期(7―12月)滇池蓝藻水华发生气象概率预测模型,并采用特征变量重要... 对滇池蓝藻水华发生的可能性进行预测,为预防和开展藻华防治、保护水环境提供科学依据。基于2001―2021年逐日MODIS数据和随机森林算法,分别构建复苏期(3―6月)和高发期(7―12月)滇池蓝藻水华发生气象概率预测模型,并采用特征变量重要性和偏依赖图定量评估了水华发生与气象因子之间的关系。结果表明:(1)近21年滇池蓝藻水华发生年累计频次和规模的均值分别为26.9次和7.30%,水华发生有明显的季节性特征。(2)影响水华发生的关键气象因子在复苏期为气温和风速,气温对水华发生的影响大于风速;高发期则为气温、风速、日照和降水,其中风速的影响最大,其次是气温,日照和降水的影响最小。(3)总体上,气温和降水会加剧蓝藻水华的发生,风速和日照则有抑制作用;气温、光照和降水对水华发生的影响具有一定的累积效应。(4)各因子对蓝藻水华的影响存在一定的适宜区间,超出或低于相应的区间可能会不利于水华的发生;当气温>18℃和风速<2.5 m/s时,发生水华的概率相对较高。(5)模型在复苏期的准确率、召回率、综合评价得分和受试者工作曲线下的面积值分别为80.1%、62.3%、63.4%和87.6%,而高发期为83.1%、85.2%、88.8%和86.0%。 展开更多
关键词 蓝藻水华 气象条件 出现概率 随机森林 滇池
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基于轻量化SE-ResNet和增量学习的铣刀磨损状态预测方法
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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》 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
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变速抽水蓄能机组水力-电气耦合仿真技术研究
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作者 许昌 卢伟甫 +5 位作者 曾雪洋 曹林宁 朱洒 冯陈 郭磊 于安 《排灌机械工程学报》 北大核心 2026年第2期164-172,共9页
为了有效提高电网安全稳定运行水平和新能源资源利用率等,构建了由有压输水系统、水泵水轮机、交流励磁发电机和调速器等组成的变速抽水蓄能机组精细化模型,对抽水蓄能电站典型水力过渡过程开展了深入的计算分析.研究结果表明,交流励磁... 为了有效提高电网安全稳定运行水平和新能源资源利用率等,构建了由有压输水系统、水泵水轮机、交流励磁发电机和调速器等组成的变速抽水蓄能机组精细化模型,对抽水蓄能电站典型水力过渡过程开展了深入的计算分析.研究结果表明,交流励磁变速机组数值仿真整机模型可有效进行各工况仿真,仿真动态过程符合机组实际运行过程,效果良好.变速抽水蓄能机组在发电工况的调速器功率模型下进行增减负荷时,机组转速由交流励磁控制,其转速可以迅速得到精确调整,定子侧有功也能快速稳定在指定值;机组在发电工况的调速器开度模型下进行增减负荷时,机组出力由交流励磁控制,定子侧有功能够快速稳定在指定值,机组转速则缓慢稳定在指定值. 展开更多
关键词 变速抽水蓄能机组 交流励磁 发电工况 调速器
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极端风况下漂浮式风力机尾流数值模拟
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作者 张立栋 刘阳 +2 位作者 陈怡冰 张磊 曹善桥 《华中科技大学学报(自然科学版)》 北大核心 2026年第1期27-32,共6页
针对漂浮式风力机尾流效应具有复杂非线性特征,极端风况引发的尾流速度突变会显著加剧这一现象,基于FAST.Farm平台构建新型三机系统(两台15 MW与一台5 MW漂浮式机组),通过调节小型机组在大型机组间的流向间距(2D和6D,D为叶轮直径),重点... 针对漂浮式风力机尾流效应具有复杂非线性特征,极端风况引发的尾流速度突变会显著加剧这一现象,基于FAST.Farm平台构建新型三机系统(两台15 MW与一台5 MW漂浮式机组),通过调节小型机组在大型机组间的流向间距(2D和6D,D为叶轮直径),重点探究极端工作阵风(EOG)、极端风向变化(EDC)、极端水平风切变(EWSH)和垂直风切变(EWSV)四种典型工况下的尾流演化规律.研究结果表明:当流向间距从2D增至6D时,小型机组对下游15 MW机组尾流影响区域下移,轮毂中心湍流强度降低10%.EOG工况下,系统整体功率提升13%,但湍流强度增幅达20%.EDC工况下,尾流效应减弱,流向间距对功率的影响减弱.极端风切变(EWS)工况下,存在着剧烈的尾流非对称性分布,EWSH工况对功率的影响显著强于EWSV工况,EWSV工况加剧了尾流的剪切效应,湍流强度波动幅度较大,应加强其载荷监测. 展开更多
关键词 风力机 极端风况 垂直串列 尾流 湍流强度
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黄油在不同贮存条件下理化品质和脂肪酸变化的研究
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作者 张振霞 《中国调味品》 北大核心 2026年第1期36-40,共5页
该研究通过模拟不同贮存条件,系统探讨了黄油在不同贮存温度和贮存时间下脂肪酸的变化规律。设置贮存温度(4,18,25,30,35℃)和贮存时间(24,72,120,240,360 h)等关键因素,考察感官评分、水分含量、脂肪含量,并利用气相色谱法(GC)和高效... 该研究通过模拟不同贮存条件,系统探讨了黄油在不同贮存温度和贮存时间下脂肪酸的变化规律。设置贮存温度(4,18,25,30,35℃)和贮存时间(24,72,120,240,360 h)等关键因素,考察感官评分、水分含量、脂肪含量,并利用气相色谱法(GC)和高效液相色谱法(HPLC)精确测定黄油中各种脂肪酸的比例和含量。结果显示,随着贮存温度的升高和贮存时间的延长,黄油的感官评分显著下降,水分含量升高,脂肪含量降低,脂肪酸组成发生变化,尤其是不饱和脂肪酸含量显著降低。结果表明,高温和长时间贮存会加速黄油中脂肪酸的氧化和微生物活动,从而导致黄油品质下降。饱和脂肪酸如棕榈酸和硬脂酸以及单不饱和脂肪酸如油酸的含量均随贮存温度升高和贮存时间延长呈下降趋势。多不饱和脂肪酸如亚油酸和亚麻酸在较高贮存温度下未被检出,表明其对贮存温度变化具有较高敏感性。此外,反式脂肪酸在长时间贮存后出现,可能与脂肪酸的氧化和微生物作用有关。 展开更多
关键词 黄油 贮存条件 理化品质 脂肪酸
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基于实车全油门加速测试的发动机瞬态特性研究
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作者 崔慧峰 刘勇 +1 位作者 钟治华 郭华锋 《内燃机》 2026年第1期26-30,共5页
为了提高整车开发过程中关键零部件选型的稳健性及整车性能评估的精度,需对全油门时发动机实际的功率、扭矩输出及其响应特性进行系统了解。以一台轻型卡车为研究对象,实施了各档位全油门加速状态下的相关参数测试,分析了各档位发动机... 为了提高整车开发过程中关键零部件选型的稳健性及整车性能评估的精度,需对全油门时发动机实际的功率、扭矩输出及其响应特性进行系统了解。以一台轻型卡车为研究对象,实施了各档位全油门加速状态下的相关参数测试,分析了各档位发动机能够实际输出的最大扭矩与发动机台架外特性测试结果之间的差异及其原因,同时分析了发动机转速响应和功率响应随档位的变化规律。研究结果表明:1档中低转速下,发动机能够实际输出的最大扭矩是小于台架外特性扭矩的;随着档位的升高,发动机实际输出的扭矩达到台架外特性扭矩所对应的转速逐渐降低,而所对应的响应时间大致呈逐渐增加的趋势;随着档位的升高,发动机的转速变化率和功率变化率总体上均呈现逐渐降低的趋势,同时,转速变化率和功率变化率的时间平均值也呈现同样趋势。相关工作可为整车开发及用户实际使用环节涉及的动力性及驾驶性预测、评估工作提供数据和理论支持。 展开更多
关键词 全油门 瞬态工况 功率 扭矩 动态响应
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变工况时漏汽对机组热经济性的影响
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作者 张瑞青 王雷 《汽轮机技术》 北大核心 2026年第1期13-16,共4页
以某300MW机组为例,计算了不同运行方式不同工况时机组的阀杆与轴封漏汽量以及漏汽量做功不足的变化,通过将漏汽引入不同的高压加热器,计算了漏汽引入位置对机组热经济性的影响。计算结果表明:定压运行时的漏汽量比滑压运行时大,随机组... 以某300MW机组为例,计算了不同运行方式不同工况时机组的阀杆与轴封漏汽量以及漏汽量做功不足的变化,通过将漏汽引入不同的高压加热器,计算了漏汽引入位置对机组热经济性的影响。计算结果表明:定压运行时的漏汽量比滑压运行时大,随机组负荷变大,滑压运行时漏汽量会增加,定压运行漏汽量基本不变;定压运行时的漏汽量做功不足比滑压运行时大,随机组负荷变大,定压运行时漏汽量做功不足减小,而滑压运行时漏汽量做功不足增加;将主汽阀泄漏点A漏汽引入1号高压加热器,机组热经济性最高;高压缸轴封漏汽点L漏汽引入1号高压加热器,机组热经济性最高;中压汽阀泄漏点K漏汽引入除氧器,机组热经济性最高。 展开更多
关键词 变工况 漏汽量 漏汽做功不足 热经济性
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