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Ethical Decision-Making Framework Based on Incremental ILP Considering Conflicts
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作者 Xuemin Wang Qiaochen Li Xuguang Bao 《Computers, Materials & Continua》 SCIE EI 2024年第3期3619-3643,共25页
Humans are experiencing the inclusion of artificial agents in their lives,such as unmanned vehicles,service robots,voice assistants,and intelligent medical care.If the artificial agents cannot align with social values... Humans are experiencing the inclusion of artificial agents in their lives,such as unmanned vehicles,service robots,voice assistants,and intelligent medical care.If the artificial agents cannot align with social values or make ethical decisions,they may not meet the expectations of humans.Traditionally,an ethical decision-making framework is constructed by rule-based or statistical approaches.In this paper,we propose an ethical decision-making framework based on incremental ILP(Inductive Logic Programming),which can overcome the brittleness of rule-based approaches and little interpretability of statistical approaches.As the current incremental ILP makes it difficult to solve conflicts,we propose a novel ethical decision-making framework considering conflicts in this paper,which adopts our proposed incremental ILP system.The framework consists of two processes:the learning process and the deduction process.The first process records bottom clauses with their score functions and learns rules guided by the entailment and the score function.The second process obtains an ethical decision based on the rules.In an ethical scenario about chatbots for teenagers’mental health,we verify that our framework can learn ethical rules and make ethical decisions.Besides,we extract incremental ILP from the framework and compare it with the state-of-the-art ILP systems based on ASP(Answer Set Programming)focusing on conflict resolution.The results of comparisons show that our proposed system can generate better-quality rules than most other systems. 展开更多
关键词 Ethical decision-making inductive logic programming incremental learning conflicts
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CNN-LSTM based incremental attention mechanism enabled phase-space reconstruction for chaotic time series prediction
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作者 Xiao-Qian Lu Jun Tian +2 位作者 Qiang Liao Zheng-Wu Xu Lu Gan 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第2期77-90,共14页
To improve the prediction accuracy of chaotic time series and reconstruct a more reasonable phase space structure of the prediction network,we propose a convolutional neural network-long short-term memory(CNN-LSTM)pre... To improve the prediction accuracy of chaotic time series and reconstruct a more reasonable phase space structure of the prediction network,we propose a convolutional neural network-long short-term memory(CNN-LSTM)prediction model based on the incremental attention mechanism.Firstly,a traversal search is conducted through the traversal layer for finite parameters in the phase space.Then,an incremental attention layer is utilized for parameter judgment based on the dimension weight criteria(DWC).The phase space parameters that best meet DWC are selected and fed into the input layer.Finally,the constructed CNN-LSTM network extracts spatio-temporal features and provides the final prediction results.The model is verified using Logistic,Lorenz,and sunspot chaotic time series,and the performance is compared from the two dimensions of prediction accuracy and network phase space structure.Additionally,the CNN-LSTM network based on incremental attention is compared with long short-term memory(LSTM),convolutional neural network(CNN),recurrent neural network(RNN),and support vector regression(SVR)for prediction accuracy.The experiment results indicate that the proposed composite network model possesses enhanced capability in extracting temporal features and achieves higher prediction accuracy.Also,the algorithm to estimate the phase space parameter is compared with the traditional CAO,false nearest neighbor,and C-C,three typical methods for determining the chaotic phase space parameters.The experiments reveal that the phase space parameter estimation algorithm based on the incremental attention mechanism is superior in prediction accuracy compared with the traditional phase space reconstruction method in five networks,including CNN-LSTM,LSTM,CNN,RNN,and SVR. 展开更多
关键词 Chaotic time series incremental attention mechanism Phase-space reconstruction
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Grouping tree species to estimate basal area increment in temperate multispecies forests in Durango,Mexico
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作者 Jaime Roberto Padilla-Martínez Carola Paul +2 位作者 Kai Husmann Jose Javier Corral-Rivas Klaus von Gadow 《Forest Ecosystems》 SCIE CSCD 2024年第1期1-13,共13页
Multispecies forests have received increased scientific attention,driven by the hypothesis that biodiversity improves ecological resilience.However,a greater species diversity presents challenges for forest management... Multispecies forests have received increased scientific attention,driven by the hypothesis that biodiversity improves ecological resilience.However,a greater species diversity presents challenges for forest management and research.Our study aims to develop basal area growth models for tree species cohorts.The analysis is based on a dataset of 423 permanent plots(2,500 m^(2))located in temperate forests in Durango,Mexico.First,we define tree species cohorts based on individual and neighborhood-based variables using a combination of principal component and cluster analyses.Then,we estimate the basal area increment of each cohort through the generalized additive model to describe the effect of tree size,competition,stand density and site quality.The principal component and cluster analyses assign a total of 37 tree species to eight cohorts that differed primarily with regard to the distribution of tree size and vertical position within the community.The generalized additive models provide satisfactory estimates of tree growth for the species cohorts,explaining between 19 and 53 percent of the total variation of basal area increment,and highlight the following results:i)most cohorts show a"rise-and-fall"effect of tree size on tree growth;ii)surprisingly,the competition index"basal area of larger trees"had showed a positive effect in four of the eight cohorts;iii)stand density had a negative effect on basal area increment,though the effect was minor in medium-and high-density stands,and iv)basal area growth was positively correlated with site quality except for an oak cohort.The developed species cohorts and growth models provide insight into their particular ecological features and growth patterns that may support the development of sustainable management strategies for temperate multispecies forests. 展开更多
关键词 Temperate multispecies forests Cluster analysis Basal area increment Generalized additive models
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Selective and Adaptive Incremental Transfer Learning with Multiple Datasets for Machine Fault Diagnosis
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作者 Kwok Tai Chui Brij B.Gupta +1 位作者 Varsha Arya Miguel Torres-Ruiz 《Computers, Materials & Continua》 SCIE EI 2024年第1期1363-1379,共17页
The visions of Industry 4.0 and 5.0 have reinforced the industrial environment.They have also made artificial intelligence incorporated as a major facilitator.Diagnosing machine faults has become a solid foundation fo... The visions of Industry 4.0 and 5.0 have reinforced the industrial environment.They have also made artificial intelligence incorporated as a major facilitator.Diagnosing machine faults has become a solid foundation for automatically recognizing machine failure,and thus timely maintenance can ensure safe operations.Transfer learning is a promising solution that can enhance the machine fault diagnosis model by borrowing pre-trained knowledge from the source model and applying it to the target model,which typically involves two datasets.In response to the availability of multiple datasets,this paper proposes using selective and adaptive incremental transfer learning(SA-ITL),which fuses three algorithms,namely,the hybrid selective algorithm,the transferability enhancement algorithm,and the incremental transfer learning algorithm.It is a selective algorithm that enables selecting and ordering appropriate datasets for transfer learning and selecting useful knowledge to avoid negative transfer.The algorithm also adaptively adjusts the portion of training data to balance the learning rate and training time.The proposed algorithm is evaluated and analyzed using ten benchmark datasets.Compared with other algorithms from existing works,SA-ITL improves the accuracy of all datasets.Ablation studies present the accuracy enhancements of the SA-ITL,including the hybrid selective algorithm(1.22%-3.82%),transferability enhancement algorithm(1.91%-4.15%),and incremental transfer learning algorithm(0.605%-2.68%).These also show the benefits of enhancing the target model with heterogeneous image datasets that widen the range of domain selection between source and target domains. 展开更多
关键词 Deep learning incremental learning machine fault diagnosis negative transfer transfer learning
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A Hybrid Optimization Approach of Single Point Incremental Sheet Forming of AISI 316L Stainless Steel Using Grey Relation Analysis Coupled with Principal Component Analysiss
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作者 A Visagan P Ganesh 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期160-166,共7页
We investigated the parametric optimization on incremental sheet forming of stainless steel using Grey Relational Analysis(GRA) coupled with Principal Component Analysis(PCA). AISI 316L stainless steel sheets were use... We investigated the parametric optimization on incremental sheet forming of stainless steel using Grey Relational Analysis(GRA) coupled with Principal Component Analysis(PCA). AISI 316L stainless steel sheets were used to develop double wall angle pyramid with aid of tungsten carbide tool. GRA coupled with PCA was used to plan the experiment conditions. Control factors such as Tool Diameter(TD), Step Depth(SD), Bottom Wall Angle(BWA), Feed Rate(FR) and Spindle Speed(SS) on Top Wall Angle(TWA) and Top Wall Angle Surface Roughness(TWASR) have been studied. Wall angle increases with increasing tool diameter due to large contact area between tool and workpiece. As the step depth, feed rate and spindle speed increase,TWASR decreases with increasing tool diameter. As the step depth increasing, the hydrostatic stress is raised causing severe cracks in the deformed surface. Hence it was concluded that the proposed hybrid method was suitable for optimizing the factors and response. 展开更多
关键词 single point incremental forming AISI 316L taguchi grey relation analysis principal component analysis surface roughness scanning electron microscopy
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Filter Bank Networks for Few-Shot Class-Incremental Learning
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作者 Yanzhao Zhou Binghao Liu +1 位作者 Yiran Liu Jianbin Jiao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期647-668,共22页
Deep Convolution Neural Networks(DCNNs)can capture discriminative features from large datasets.However,how to incrementally learn new samples without forgetting old ones and recognize novel classes that arise in the d... Deep Convolution Neural Networks(DCNNs)can capture discriminative features from large datasets.However,how to incrementally learn new samples without forgetting old ones and recognize novel classes that arise in the dynamically changing world,e.g.,classifying newly discovered fish species,remains an open problem.We address an even more challenging and realistic setting of this problem where new class samples are insufficient,i.e.,Few-Shot Class-Incremental Learning(FSCIL).Current FSCIL methods augment the training data to alleviate the overfitting of novel classes.By contrast,we propose Filter Bank Networks(FBNs)that augment the learnable filters to capture fine-detailed features for adapting to future new classes.In the forward pass,FBNs augment each convolutional filter to a virtual filter bank containing the canonical one,i.e.,itself,and multiple transformed versions.During back-propagation,FBNs explicitly stimulate fine-detailed features to emerge and collectively align all gradients of each filter bank to learn the canonical one.FBNs capture pattern variants that do not yet exist in the pretraining session,thus making it easy to incorporate new classes in the incremental learning phase.Moreover,FBNs introduce model-level prior knowledge to efficiently utilize the limited few-shot data.Extensive experiments on MNIST,CIFAR100,CUB200,andMini-ImageNet datasets show that FBNs consistently outperformthe baseline by a significantmargin,reporting new state-of-the-art FSCIL results.In addition,we contribute a challenging FSCIL benchmark,Fishshot1K,which contains 8261 underwater images covering 1000 ocean fish species.The code is included in the supplementary materials. 展开更多
关键词 Deep learning incremental learning few-shot learning Filter Bank Networks
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Incremental Learning Based on Data Translation and Knowledge Distillation
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作者 Tan Cheng Jielong Wang 《International Journal of Intelligence Science》 2023年第2期33-47,共15页
Recently, deep convolutional neural networks (DCNNs) have achieved remarkable results in image classification tasks. Despite convolutional networks’ great successes, their training process relies on a large amount of... Recently, deep convolutional neural networks (DCNNs) have achieved remarkable results in image classification tasks. Despite convolutional networks’ great successes, their training process relies on a large amount of data prepared in advance, which is often challenging in real-world applications, such as streaming data and concept drift. For this reason, incremental learning (continual learning) has attracted increasing attention from scholars. However, incremental learning is associated with the challenge of catastrophic forgetting: the performance on previous tasks drastically degrades after learning a new task. In this paper, we propose a new strategy to alleviate catastrophic forgetting when neural networks are trained in continual domains. Specifically, two components are applied: data translation based on transfer learning and knowledge distillation. The former translates a portion of new data to reconstruct the partial data distribution of the old domain. The latter uses an old model as a teacher to guide a new model. The experimental results on three datasets have shown that our work can effectively alleviate catastrophic forgetting by a combination of the two methods aforementioned. 展开更多
关键词 incremental Domain Learning Data Translation Knowledge Distillation Cat-astrophic Forgetting
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ILIDViz:An incremental learning-based visual analysis system for network anomaly detection
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作者 Xuefei TIAN Zhiyuan WU +2 位作者 Junxiang CAO Shengtao CHEN Xiaoju DONG 《Virtual Reality & Intelligent Hardware》 EI 2023年第6期471-489,共19页
Background With the development of information technology,there is a significant increase in the number of network traffic logs mixed with various types of cyberattacks.Traditional intrusion detection systems(IDSs)are... Background With the development of information technology,there is a significant increase in the number of network traffic logs mixed with various types of cyberattacks.Traditional intrusion detection systems(IDSs)are limited in detecting new inconstant patterns and identifying malicious traffic traces in real time.Therefore,there is an urgent need to implement more effective intrusion detection technologies to protect computer security.Methods In this study,we designed a hybrid IDS by combining our incremental learning model(KANSOINN)and active learning to learn new log patterns and detect various network anomalies in real time.Conclusions Experimental results on the NSLKDD dataset showed that KAN-SOINN can be continuously improved and effectively detect malicious logs.Meanwhile,comparative experiments proved that using a hybrid query strategy in active learning can improve the model learning efficiency. 展开更多
关键词 Intrusion detection Machine learning incremental learning Active learning Visual analysis
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A Novel Incremental Attribute Reduction Algorithm Based on Intuitionistic Fuzzy Partition Distance
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作者 Pham Viet Anh Nguyen Ngoc Thuy +2 位作者 Nguyen Long Giang Pham Dinh Khanh Nguyen The Thuy 《Computer Systems Science & Engineering》 SCIE EI 2023年第12期2971-2988,共18页
Attribute reduction,also known as feature selection,for decision information systems is one of the most pivotal issues in machine learning and data mining.Approaches based on the rough set theory and some extensions w... Attribute reduction,also known as feature selection,for decision information systems is one of the most pivotal issues in machine learning and data mining.Approaches based on the rough set theory and some extensions were proved to be efficient for dealing with the problemof attribute reduction.Unfortunately,the intuitionistic fuzzy sets based methods have not received much interest,while these methods are well-known as a very powerful approach to noisy decision tables,i.e.,data tables with the low initial classification accuracy.Therefore,this paper provides a novel incremental attribute reductionmethod to dealmore effectivelywith noisy decision tables,especially for highdimensional ones.In particular,we define a new reduct and then design an original attribute reduction method based on the distance measure between two intuitionistic fuzzy partitions.It should be noted that the intuitionistic fuzzypartitiondistance iswell-knownas aneffectivemeasure todetermine important attributes.More interestingly,an incremental formula is also developed to quickly compute the intuitionistic fuzzy partition distance in case when the decision table increases in the number of objects.This formula is then applied to construct an incremental attribute reduction algorithm for handling such dynamic tables.Besides,some experiments are conducted on real datasets to show that our method is far superior to the fuzzy rough set based methods in terms of the size of reduct and the classification accuracy. 展开更多
关键词 incremental attribute reduction intuitionistic fuzzy sets partition distance measure dynamic decision tables
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Multi-scale Incremental Analysis Update Scheme and Its Application to Typhoon Mangkhut(2018)Prediction
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作者 Yan GAO Jiali FENG +4 位作者 Xin XIA Jian SUN Yulong MA Dongmei CHEN Qilin WAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第1期95-109,共15页
In the traditional incremental analysis update(IAU)process,all analysis increments are treated as constant forcing in a model’s prognostic equations over a certain time window.This approach effectively reduces high-f... In the traditional incremental analysis update(IAU)process,all analysis increments are treated as constant forcing in a model’s prognostic equations over a certain time window.This approach effectively reduces high-frequency oscillations introduced by data assimilation.However,as different scales of increments have unique evolutionary speeds and life histories in a numerical model,the traditional IAU scheme cannot fully meet the requirements of short-term forecasting for the damping of high-frequency noise and may even cause systematic drifts.Therefore,a multi-scale IAU scheme is proposed in this paper.Analysis increments were divided into different scale parts using a spatial filtering technique.For each scale increment,the optimal relaxation time in the IAU scheme was determined by the skill of the forecasting results.Finally,different scales of analysis increments were added to the model integration during their optimal relaxation time.The multi-scale IAU scheme can effectively reduce the noise and further improve the balance between large-scale and small-scale increments in the model initialization stage.To evaluate its performance,several numerical experiments were conducted to simulate the path and intensity of Typhoon Mangkhut(2018)and showed that:(1)the multi-scale IAU scheme had an obvious effect on noise control at the initial stage of data assimilation;(2)the optimal relaxation time for large-scale and small-scale increments was estimated as 6 h and 3 h,respectively;(3)the forecast performance of the multi-scale IAU scheme in the prediction of Typhoon Mangkhut(2018)was better than that of the traditional IAU scheme.The results demonstrate the superiority of the multi-scale IAU scheme. 展开更多
关键词 multi-scale incremental analysis updates optimal relaxation time 2-D discrete cosine transform GRAPES_MESO Typhoon Mangkhut(2018)
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城乡建设用地增减挂钩节余指标跨省域调剂的扶贫效应
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作者 王艺明 傅龙 《财政科学》 2024年第5期20-37,共18页
允许城乡建设用地增减挂钩节余指标跨省域调剂的政策突破了土地资源在空间上的限制,提升了土地资源在全国范围内的配置效率。本文着眼于探究该政策的扶贫效应及其机制,以农民收入作为扶贫效应的代表,运用双重差分(DID)方法,研究了该政... 允许城乡建设用地增减挂钩节余指标跨省域调剂的政策突破了土地资源在空间上的限制,提升了土地资源在全国范围内的配置效率。本文着眼于探究该政策的扶贫效应及其机制,以农民收入作为扶贫效应的代表,运用双重差分(DID)方法,研究了该政策对“三区三州”原贫困县农村人均可支配收入的影响。实证研究结果表明,实施该政策的原贫困县农村人均可支配收入显著提高。进一步研究表明,该政策通过推动城镇化和促进产业结构升级两个方面,增强了地区的“造血”能力,取得了实质性的扶贫效果。这一发现强调了政策对地方经济的积极影响,为深入理解土地资源配置与扶贫关系提供了重要的实证支持。 展开更多
关键词 双重差分方法 增减挂钩 农民收入 城镇化 产业发展
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基于分布式潮流控制器的海上风电系统谐波治理方法和控制策略 被引量:1
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作者 唐爱红 宋幸 +3 位作者 尚宇菲 郭国伟 余梦琪 詹细妹 《电力系统自动化》 EI CSCD 北大核心 2024年第2期20-28,共9页
由于电力电缆的电容效应,海上风电经电缆汇集系统极易出现谐波谐振放大的现象,造成电能质量的下降。分布式潮流控制器属于基于电压源换流器的装置,在进行潮流调节的同时也能进行谐波治理。文中首先构建了海上风电系统的频域相关模型,基... 由于电力电缆的电容效应,海上风电经电缆汇集系统极易出现谐波谐振放大的现象,造成电能质量的下降。分布式潮流控制器属于基于电压源换流器的装置,在进行潮流调节的同时也能进行谐波治理。文中首先构建了海上风电系统的频域相关模型,基于该模型分析了谐波谐振放大的原因;随后,采用了将分布式潮流控制器串入海上风电系统的谐波治理方式,推导并得到了含分布式潮流控制器的海上风电系统的谐波特性。基于该谐波特性,设计了一种控制策略。该策略通过控制分布式潮流控制器实时跟踪使并网点谐波电压幅值为零的谐波补偿电压,从而降低并网点的谐波电压含量。仿真结果表明,所提出的基于分布式潮流控制器的海上风电系统谐波治理方法和控制策略能够有效地降低并网点的谐波电压,改善电能质量。 展开更多
关键词 海上风电 电能质量 谐波治理 分布式潮流控制器 变增量电导增量法
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寒区环境温度对板式橡胶支座连续梁桥地震易损性影响研究 被引量:1
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作者 虞庐松 王力 +2 位作者 杜新龙 李子奇 李於钱 《地震工程学报》 CSCD 北大核心 2024年第1期105-114,共10页
针对现行规范对寒区桥梁减隔震设计中仅考虑橡胶支座力学特性受环境温度作用影响,而忽略桥墩混凝土材料特性受温度影响的不足,以高寒地区一座两联3×30 m混凝土连续梁桥为背景,开展不同环境温度下桥墩混凝土材料抗压性能试验,确定... 针对现行规范对寒区桥梁减隔震设计中仅考虑橡胶支座力学特性受环境温度作用影响,而忽略桥墩混凝土材料特性受温度影响的不足,以高寒地区一座两联3×30 m混凝土连续梁桥为背景,开展不同环境温度下桥墩混凝土材料抗压性能试验,确定温度对其力学参数的影响,基于试验结果对不同环境温度下的桥墩混凝土力学参数进行修正,从而建立不同环境温度下的全桥精细化非线性有限元模型,并基于增量动力分析(IDA)法探究不同环境温度下该桥的地震易损性。结果表明:极端温度引起桥墩混凝土材料参数和支座刚度的改变,使得该桥自振频率随着温度的升高而降低;地震作用下,极端低温时桥墩墩顶位移较常温增大了26.8%,而极端高温时支座位移增大了19.4%;根据现行规范计算的极端低温时支座和桥梁系统的损伤概率偏小,极端高温时结构和构件的损伤概率偏大,在设计中应予以重视;极端低温下桥墩、支座及桥梁系统的损伤概率,较常温分别增大45.0%、35.2%和27.5%,对于高寒地区该类桥梁设计时需考虑低温对其抗震性能的影响。 展开更多
关键词 环境温度 板式橡胶支座 摩擦滑移 连续梁桥 增量动力分析 地震易损性
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基于振动台试验的鱼线固定梅瓶文物响应规律性研究 被引量:1
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作者 杨维国 高雅巍 +3 位作者 王萌 刘佩 葛家琪 邹晓光 《振动与冲击》 EI CSCD 北大核心 2024年第4期250-260,共11页
为了探索鱼线固定梅瓶文物在实际博物馆的地震响应以及抗震效果,首先选取了典型梅瓶文物,并在三层钢筋混凝土框架结构中开展了24种地震工况的振动台试验,然后建立了上述试验所用梅瓶文物的有限元模型,验证了有限元模型的准确性,最后采... 为了探索鱼线固定梅瓶文物在实际博物馆的地震响应以及抗震效果,首先选取了典型梅瓶文物,并在三层钢筋混凝土框架结构中开展了24种地震工况的振动台试验,然后建立了上述试验所用梅瓶文物的有限元模型,验证了有限元模型的准确性,最后采用增量动力分析法分析了该文物在两种常见直径鱼线保护措施下的运动响应。结果表明:鱼线固定梅瓶文物在地震作用下会产生滑移、摇摆、倾覆以及鱼线断裂等现象;不同楼层下的文物响应差别较大,尤其在大震作用下,高楼层的鱼线固定梅瓶文物易发生倾覆和鱼线断裂破坏,要重视高楼层文物的震前保护措施;在较强的地震作用下,仅依靠增大鱼线直径有时对控制文物的倾覆情况起不到关键性决定作用,需要进一步采取其它措施对文物进行保护。 展开更多
关键词 鱼线固定梅瓶文物 振动台试验 有限元模型 运动响应 增量动力分析
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数字物流赋能可持续发展的机制与效应——基于物流碳生产率视角 被引量:2
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作者 马晓君 聂昀秋 肖潇 《中国流通经济》 北大核心 2024年第4期68-79,共12页
在社会经济全面数字化和可持续发展背景下,从物流碳生产率视角探究数字物流赋能可持续发展的机制与效应意义重大。基于2015—2020年我国省际面板数据,运用纵横向拉开档次法和CRITIC-G1-Bonferroni算子,分别对各地区数字物流和可持续发... 在社会经济全面数字化和可持续发展背景下,从物流碳生产率视角探究数字物流赋能可持续发展的机制与效应意义重大。基于2015—2020年我国省际面板数据,运用纵横向拉开档次法和CRITIC-G1-Bonferroni算子,分别对各地区数字物流和可持续发展水平进行测算,进而以面板固定效应模型、中介效应模型、门槛模型和空间模型,对数字物流、物流碳生产率与可持续发展之间的逻辑关系进行实证检验。研究发现,数字物流以非线性递增的态势显著促进可持续发展水平的提升,且在东部、东北地区的作用强于中西部地区;其中,物流碳生产率的提高是数字物流释放可持续发展红利的重要机制。同时,数字物流对可持续发展还具有空间溢出效应,表明其对地区间可持续发展水平相互协调、带动也有着不可忽视的积极作用;随着传统产业全面数字化对可持续发展水平的影响不断加深,该溢出效应变得愈加显著,从而带动地区可持续发展水平的均衡提升。为了巩固数字物流为可持续发展带来的红利优势,首先要促进社会资本参与物流数字化转型,建设共享的物流平台和基础设施,淘汰过剩落后产能,形成开放统一的物流市场,并通过设立管理部门制定并监督低碳环保标准。此外,应通过财政支持和税收优惠加强中西部基础设施建设,同时建立地区合作机制,共享资源和技术,优化物流网络,促进区域间协调发展。 展开更多
关键词 数字物流 可持续发展 物流碳生产率 非线性递增 空间溢出效应
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基于在线自组织增量学习的非侵入式负荷识别方法
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作者 胡正伟 王志红 +2 位作者 畅瑞鑫 谢志远 曹旺斌 《工程科学与技术》 EI CAS CSCD 北大核心 2024年第4期316-324,共9页
随着电子技术智能化的发展,对实现电器负荷使用情况的精准识别在智慧用电领域将有广泛的用户需求。为了实现对电器设备的实时在线精确监测,本文提出了一种基于在线自组织增量学习(SOINN)的非侵入式负荷识别方法。该方法包含负荷特征提... 随着电子技术智能化的发展,对实现电器负荷使用情况的精准识别在智慧用电领域将有广泛的用户需求。为了实现对电器设备的实时在线精确监测,本文提出了一种基于在线自组织增量学习(SOINN)的非侵入式负荷识别方法。该方法包含负荷特征提取、负荷特征分类及电器识别2个步骤。在负荷特征提取步骤中,提出了包含奇次谐波、均值、方差、3阶矩、4阶矩、电流有效值、功率谱峰值、功率谱谷值在内的共12维特征的特征提取方案。在负荷特征分类及电器识别步骤中,提出了结合SVM的SOINN的负荷特征分类及电器识别方法,以克服传统的SOINN算法不能实现电器类型识别功能的缺陷。通过C++语言将所提方法中的功能算法编写成微处理器系统的可执行功能模块,将功能模块移植部署在SoCFPGA的HPS端运行,实现了FPGA和HPS之间的协同高速数据通信。选取了8种常规家用电器作为负荷识别对象,搭建了基于SoCFPGA的硬件实验平台,进行了最优负荷特征选取,并采用本文方法对单电器与多电器的在线负荷进行了识别。实验结果:选取12维特征为本文方法的最优特征组合;本文方法的单电器与多电器的识别率均在95%以上。本文提出的负荷识别方法能够有效、准确地识别单电器与多电器;系统可实施性强,灵活性高,具有在线学习的优越性与实际应用的切实可行性。 展开更多
关键词 增量学习 负荷识别 12维样本特征 FPGA
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基于增量学习的车联网恶意位置攻击检测研究
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作者 江荣旺 魏爽 +1 位作者 龙草芳 杨明 《信息安全研究》 CSCD 北大核心 2024年第3期268-276,共9页
近年来,车辆恶意位置攻击检测中主要使用深度学习技术.然而,深度学习模型训练耗时巨大、参数众多,基于深度学习的检测方法缺乏可扩展性,无法适应车联网不断产生新数据的需求.为了解决以上问题,创新地将增量学习算法引入车辆恶意位置攻... 近年来,车辆恶意位置攻击检测中主要使用深度学习技术.然而,深度学习模型训练耗时巨大、参数众多,基于深度学习的检测方法缺乏可扩展性,无法适应车联网不断产生新数据的需求.为了解决以上问题,创新地将增量学习算法引入车辆恶意位置攻击检测中,解决了上述问题.首先从采集到的车辆信息数据中提取关键特征;然后,构建恶意位置攻击检测系统,利用岭回归近似快速地计算出车联网恶意位置攻击检测模型;最后,通过增量学习算法对恶意位置攻击检测模型进行更新和优化,以适应车联网中新生成的数据.实验结果表明,相比SVM,KNN,ANN等方法具有更优秀的性能,能够快速且渐进地更新和优化旧模型,提高系统对恶意位置攻击行为的检测精度. 展开更多
关键词 车联网 恶意位置攻击检测 增量学习 深度学习 机器学习
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避免近期偏好的自学习掩码分区增量学习
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作者 姚红革 邬子逸 +5 位作者 马姣姣 石俊 程嗣怡 陈游 喻钧 姜虹 《软件学报》 EI CSCD 北大核心 2024年第7期3428-3453,共26页
遗忘是人工神经网络在增量学习中的最大问题,被称为“灾难性遗忘”.而人类可以持续地获取新知识,并能保存大部分经常用到的旧知识.人类的这种能持续“增量学习”而很少遗忘是与人脑具有分区学习结构和记忆回放能力相关的.为模拟人脑的... 遗忘是人工神经网络在增量学习中的最大问题,被称为“灾难性遗忘”.而人类可以持续地获取新知识,并能保存大部分经常用到的旧知识.人类的这种能持续“增量学习”而很少遗忘是与人脑具有分区学习结构和记忆回放能力相关的.为模拟人脑的这种结构和能力,提出一种“避免近期偏好的自学习掩码分区增量学习方法”简称ASPIL.它包含“区域隔离”和“区域集成”两阶段,二者交替迭代实现持续的增量学习.首先,提出“BN稀疏区域隔离”方法,将新的学习过程与现有知识隔离,避免干扰现有知识;对于“区域集成”,提出自学习掩码(SLM)和双分支融合(GBF)方法.其中SLM准确提取新知识,并提高网络对新知识的适应性,而GBF将新旧知识融合,以达到建立统一的、高精度的认知的目的;训练时,为确保进一步兼顾旧知识,避免对新知识的偏好,提出间隔损失正则项来避免“近期偏好”问题.为评估以上所提出方法的效用,在增量学习标准数据集CIFAR-100和miniImageNet上系统地进行消融实验,并与最新的一系列知名方法进行比较.实验结果表明,所提方法提高了人工神经网络的记忆能力,与最新知名方法相比识别率平均提升5.27%以上. 展开更多
关键词 增量学习 灾难性遗忘 持续学习 自学习掩码 近期偏好 区域隔离
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基于增量非线性动态逆的导弹解耦控制设计
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作者 陈星阳 赵霞 +1 位作者 周小志 李良 《弹箭与制导学报》 北大核心 2024年第2期76-81,共6页
针对导弹大迎角机动存在强耦合动力学特点,提出了一种基于增量非线性动态逆的解耦控制方法,将自动驾驶仪分为高带宽的快变角速率内回路和低带宽的慢变角回路控制,用部分逆近似求解的方法分别设计了增量形式的动态逆控制律对消不同的耦合... 针对导弹大迎角机动存在强耦合动力学特点,提出了一种基于增量非线性动态逆的解耦控制方法,将自动驾驶仪分为高带宽的快变角速率内回路和低带宽的慢变角回路控制,用部分逆近似求解的方法分别设计了增量形式的动态逆控制律对消不同的耦合项,实现控制解耦的目的。典型工况数字仿真结果表明,所设计的导弹增量非线性动态逆控制解耦律大大改善了强耦合动力学下的稳定控制性能。相比传统PID控制,它能够完全消除过载响应的低频振荡和超调量,同时还使得滚转角响应能够准确跟踪指令。 展开更多
关键词 自动驾驶仪 耦合 增量非线性动态逆 解耦控制
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工艺参数对AZ31B镁合金单点渐进翻边精度的影响
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作者 安治国 叶了 +2 位作者 张涛 门正兴 高正源 《精密成形工程》 北大核心 2024年第5期99-107,共9页
目的以AZ31B镁合金板为研究对象,研究初始成形角、工具直径、成形温度及层间距对单点渐进圆孔翻边精度的影响规律。方法使用有限元软件对2 mm厚的镁合金板材进行数值模拟,通过计算翻边直壁处的平均回弹量,得出不同工艺参数对单点渐进圆... 目的以AZ31B镁合金板为研究对象,研究初始成形角、工具直径、成形温度及层间距对单点渐进圆孔翻边精度的影响规律。方法使用有限元软件对2 mm厚的镁合金板材进行数值模拟,通过计算翻边直壁处的平均回弹量,得出不同工艺参数对单点渐进圆孔翻边直壁轮廓的影响规律。通过正交实验分析了交互作用下工艺参数对圆孔翻边直壁处平均回弹量的影响,通过极差分析确定了最优工艺参数组合,并通过实验对所得结果进行了验证。结果随着初始成形角的增大、工具直径的增大、成形温度的升高及层间距的减小,圆孔翻边制件直壁处的成形精度提高,各因素按影响程度由大到小的顺序依次为:成形温度、初始成形角、工具直径和层间距。成形精度最高的工艺参数组合如下:初始成形角为30°、工具直径为10 mm、成形温度为275℃、层间距为0.5 mm。结论采用仿真模型模拟单点渐进圆孔翻边过程具有较高的准确性,使用优化后的工艺参数得到翻边零件直壁区域的最小厚度以及平均回弹量与仿真结果误差均在3%以内,升高温度可以明显提高单点渐进圆孔翻边的制件精度。 展开更多
关键词 镁合金 翻边 单点渐进成形 数值模拟 回弹
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