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Grid Side Distributed Energy Storage Cloud Group End Region Hierarchical Time-Sharing Configuration Algorithm Based onMulti-Scale and Multi Feature Convolution Neural Network
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作者 Wen Long Bin Zhu +3 位作者 Huaizheng Li Yan Zhu Zhiqiang Chen Gang Cheng 《Energy Engineering》 EI 2023年第5期1253-1269,共17页
There is instability in the distributed energy storage cloud group end region on the power grid side.In order to avoid large-scale fluctuating charging and discharging in the power grid environment and make the capaci... There is instability in the distributed energy storage cloud group end region on the power grid side.In order to avoid large-scale fluctuating charging and discharging in the power grid environment and make the capacitor components showa continuous and stable charging and discharging state,a hierarchical time-sharing configuration algorithm of distributed energy storage cloud group end region on the power grid side based on multi-scale and multi feature convolution neural network is proposed.Firstly,a voltage stability analysis model based onmulti-scale and multi feature convolution neural network is constructed,and the multi-scale and multi feature convolution neural network is optimized based on Self-OrganizingMaps(SOM)algorithm to analyze the voltage stability of the cloud group end region of distributed energy storage on the grid side under the framework of credibility.According to the optimal scheduling objectives and network size,the distributed robust optimal configuration control model is solved under the framework of coordinated optimal scheduling at multiple time scales;Finally,the time series characteristics of regional power grid load and distributed generation are analyzed.According to the regional hierarchical time-sharing configuration model of“cloud”,“group”and“end”layer,the grid side distributed energy storage cloud group end regional hierarchical time-sharing configuration algorithm is realized.The experimental results show that after applying this algorithm,the best grid side distributed energy storage configuration scheme can be determined,and the stability of grid side distributed energy storage cloud group end region layered timesharing configuration can be improved. 展开更多
关键词 Multiscale and multi feature convolution neural network distributed energy storage at grid side cloud group end region layered time-sharing configuration algorithm
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基于Multitask⁃YOLO网络的卫星帆板ISAR图像快速分割
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作者 姚雨晴 汪玲 +3 位作者 王莲子 张弓 吴斌 朱岱寅 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第2期253-262,共10页
随着空间技术的飞速发展,空间态势感知能力需求不断增加。与传统光学传感器相比,逆合成孔径雷达(Inverse synthetic aperture radar,ISAR)具有全天候、远距离高分辨率成像的能力,且成像不受光照条件的影响。此外,空间态势感知系统需要... 随着空间技术的飞速发展,空间态势感知能力需求不断增加。与传统光学传感器相比,逆合成孔径雷达(Inverse synthetic aperture radar,ISAR)具有全天候、远距离高分辨率成像的能力,且成像不受光照条件的影响。此外,空间态势感知系统需要对周围航天器进行准确的评估,因此对空间目标部件识别能力的需求日益迫切。本文提出了一种基于YOLOv5结构的Multitask⁃YOLO网络,用于卫星ISAR图像中卫星帆板的识别和分割。首先,本文添加了分割解耦头来实现网络的分割功能。然后用空间金字塔池快速算法(Spatial pyramid pooling fast,SPPF)和距离交并比算法(Distance intersection over union,DIoU)代替原有结构,避免图像失真,加快收敛速度。通过在通道中引入注意机制,提高了分割和识别的准确性。最后使用模拟卫星的ISAR图像进行实验。结果表明,所提出的Multitask⁃YOLO网络高效、准确地实现了部件的识别和分割。与其他的识别和分割网络相比,该网络的平均精度(mean Average precision,mAP)和平均交并比(mean Intersection over union,mIoU)提高了约5%。此外,该网络的运行速度高达16.4 GFLOP,优于传统的多任务网络的性能。 展开更多
关键词 multitask⁃YOLO 空间目标 逆合成孔径雷达图像 目标识别与分割
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Constraints Separation Based Evolutionary Multitasking for Constrained Multi-Objective Optimization Problems
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作者 Kangjia Qiao Jing Liang +4 位作者 Kunjie Yu Xuanxuan Ban Caitong Yue Boyang Qu Ponnuthurai Nagaratnam Suganthan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第8期1819-1835,共17页
Constrained multi-objective optimization problems(CMOPs)generally contain multiple constraints,which not only form multiple discrete feasible regions but also reduce the size of optimal feasible regions,thus they prop... Constrained multi-objective optimization problems(CMOPs)generally contain multiple constraints,which not only form multiple discrete feasible regions but also reduce the size of optimal feasible regions,thus they propose serious challenges for solvers.Among all constraints,some constraints are highly correlated with optimal feasible regions;thus they can provide effective help to find feasible Pareto front.However,most of the existing constrained multi-objective evolutionary algorithms tackle constraints by regarding all constraints as a whole or directly ignoring all constraints,and do not consider judging the relations among constraints and do not utilize the information from promising single constraints.Therefore,this paper attempts to identify promising single constraints and utilize them to help solve CMOPs.To be specific,a CMOP is transformed into a multitasking optimization problem,where multiple auxiliary tasks are created to search for the Pareto fronts that only consider a single constraint respectively.Besides,an auxiliary task priority method is designed to identify and retain some high-related auxiliary tasks according to the information of relative positions and dominance relationships.Moreover,an improved tentative method is designed to find and transfer useful knowledge among tasks.Experimental results on three benchmark test suites and 11 realworld problems with different numbers of constraints show better or competitive performance of the proposed method when compared with eight state-of-the-art peer methods. 展开更多
关键词 Constrained multi-objective optimization(CMOPs) evolutionary multitasking knowledge transfer single constraint.
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A deep multimodal fusion and multitasking trajectory prediction model for typhoon trajectory prediction to reduce flight scheduling cancellation
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作者 TANG Jun QIN Wanting +1 位作者 PAN Qingtao LAO Songyang 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期666-678,共13页
Natural events have had a significant impact on overall flight activity,and the aviation industry plays a vital role in helping society cope with the impact of these events.As one of the most impactful weather typhoon... Natural events have had a significant impact on overall flight activity,and the aviation industry plays a vital role in helping society cope with the impact of these events.As one of the most impactful weather typhoon seasons appears and continues,airlines operating in threatened areas and passengers having travel plans during this time period will pay close attention to the development of tropical storms.This paper proposes a deep multimodal fusion and multitasking trajectory prediction model that can improve the reliability of typhoon trajectory prediction and reduce the quantity of flight scheduling cancellation.The deep multimodal fusion module is formed by deep fusion of the feature output by multiple submodal fusion modules,and the multitask generation module uses longitude and latitude as two related tasks for simultaneous prediction.With more dependable data accuracy,problems can be analysed rapidly and more efficiently,enabling better decision-making with a proactive versus reactive posture.When multiple modalities coexist,features can be extracted from them simultaneously to supplement each other’s information.An actual case study,the typhoon Lichma that swept China in 2019,has demonstrated that the algorithm can effectively reduce the number of unnecessary flight cancellations compared to existing flight scheduling and assist the new generation of flight scheduling systems under extreme weather. 展开更多
关键词 flight scheduling optimization deep multimodal fusion multitasking trajectory prediction typhoon weather flight cancellation prediction reliability
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A time-sharing multi-channel pulse amplitude analyzer 被引量:2
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作者 Lian-Jun Jiang Xiang Zhou +1 位作者 Tong-Yu Wu Ze-Jie Yin 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第4期91-96,共6页
A conventional multi-channel pulse amplitude analyzer acquires single energy spectrum,but provides no information on its tendency with time.To address the limitation,we propose a scheme of time-sharing multichannel pu... A conventional multi-channel pulse amplitude analyzer acquires single energy spectrum,but provides no information on its tendency with time.To address the limitation,we propose a scheme of time-sharing multichannel pulse amplitude analyzer(TSMCA).A dual-port random access memory is divided into two storage spaces,one for current energy spectrum data acquisition and another for previous energy spectrum data storage.The two tasks can be performed simultaneously,and the time-related variation tendency of energy spectrum can be obtained.A prototype system of TSMCA is designed.It performs nicely,with maximum channel number of 4096 in capacity of 2^(32)/Ch,minimal time-sharing slice of 25 ms,the differential nonlinearity of <1.5%,and the integral nonlinearity of <0.3%. 展开更多
关键词 MULTI-CHANNEL pulse AMPLITUDE ANALYZER MCA time-sharing ADC DUAL-PORT RAM
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Driving Mechanism of Cotton Comber's Detaching Roller Based on Time-Sharing Unidirectional Drive 被引量:3
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作者 李新荣 蒋秀明 +1 位作者 王生泽 王晓维 《Journal of Donghua University(English Edition)》 EI CAS 2014年第4期429-432,共4页
The high-speed reciprocating motion of a detaching roller limits the velocity of a cotton comber and affects the quality of comber slivers. The article has proposed a controllable time-sharing unidirectional hybrid dr... The high-speed reciprocating motion of a detaching roller limits the velocity of a cotton comber and affects the quality of comber slivers. The article has proposed a controllable time-sharing unidirectional hybrid drive mechanism after analyzing detaching roller's current numerical control drive method. The analysis focuses on the detaching roller motion required according to cotton comber's velocity and process. The double-servo motors of the mechanism consists of differential gear trains. The mechanism addresses the problem of increased servo motor power,and failure of promptly responded to the positive inversion process of mechanism driven by servo motors. A velocity calculation model of the detaching roller controllable drive mechanism will be generated by using superposition method and design of differential gear trains. The accuracy of the model will be verified using the test platform. This study has presented a reliable and practical high-speed drive mechanism and can be a reference to future studies on high-speed reciprocating motion drive. 展开更多
关键词 cotton comber detaching roller time-sharing unidirectional drive hybrid drive differential gear train
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Evolutionary Multitasking With Global and Local Auxiliary Tasks for Constrained Multi-Objective Optimization 被引量:1
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作者 Kangjia Qiao Jing Liang +3 位作者 Zhongyao Liu Kunjie Yu Caitong Yue Boyang Qu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第10期1951-1964,共14页
Constrained multi-objective optimization problems(CMOPs) include the optimization of objective functions and the satisfaction of constraint conditions, which challenge the solvers.To solve CMOPs, constrained multi-obj... Constrained multi-objective optimization problems(CMOPs) include the optimization of objective functions and the satisfaction of constraint conditions, which challenge the solvers.To solve CMOPs, constrained multi-objective evolutionary algorithms(CMOEAs) have been developed. However, most of them tend to converge into local areas due to the loss of diversity. Evolutionary multitasking(EMT) is new model of solving complex optimization problems, through the knowledge transfer between the source task and other related tasks. Inspired by EMT, this paper develops a new EMT-based CMOEA to solve CMOPs, in which the main task, a global auxiliary task, and a local auxiliary task are created and optimized by one specific population respectively. The main task focuses on finding the feasible Pareto front(PF), and global and local auxiliary tasks are used to respectively enhance global and local diversity. Moreover, the global auxiliary task is used to implement the global search by ignoring constraints, so as to help the population of the main task pass through infeasible obstacles. The local auxiliary task is used to provide local diversity around the population of the main task, so as to exploit promising regions. Through the knowledge transfer among the three tasks, the search ability of the population of the main task will be significantly improved. Compared with other state-of-the-art CMOEAs, the experimental results on three benchmark test suites demonstrate the superior or competitive performance of the proposed CMOEA. 展开更多
关键词 Constrained multi-objective optimization evolutionary multitasking(EMT) global auxiliary task knowledge transfer local auxiliary task
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Holistic care model of time-sharing management for severe and critical COVID-19 patients
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作者 Bo Yang Yang Gao +7 位作者 Kai Kang Jing Li Lei Wang Hui Wang Ying Bi Qing-Qing Dai Ming-Yan Zhao Kai-Jiang Yu 《World Journal of Clinical Cases》 SCIE 2020年第22期5513-5517,共5页
The rapid global outbreak of coronavirus disease 2019(COVID-19)and the surge of infected patients have led to the verge of exhaustion of critical care medicine resources worldwide,especially with regard to critical ca... The rapid global outbreak of coronavirus disease 2019(COVID-19)and the surge of infected patients have led to the verge of exhaustion of critical care medicine resources worldwide,especially with regard to critical care staff.A holistic care model on time-sharing management for severe and critical COVID-19 patients is proposed,which includes formulation of individualized care objectives and plans,identification of care tasks in each shift and making detailed checklist,and management of quality of care.This study was conducted in the COVID-19 treatment center of Harbin,Heilongjiang Province.The data collected from the treatment center were recorded and analyzed.From the results we can deduce that it is especially suitable for non-intensive care unit(non-ICU)nurses to adapt care management mode of ICU as soon as possible and ensure the quality and efficiency of care during the epidemic.The holistic care model on time-sharing management for severe and critical cases with COVID-19 proposed based on our daily work experiences can assist in improving the quality and efficiency of care,thus reducing the mortality rate of patients in ICU. 展开更多
关键词 Holistic care model time-sharing management COVID-19 Quality of care Efficiency of care Hierarchical management
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Evolutionary Multitask Optimization in Real-World Applications: A Survey 被引量:2
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作者 Yue Wu Hangqi Ding +5 位作者 Benhua Xiang Jinlong Sheng Wenping Ma Kai Qin Qiguang Miao Maoguo Gong 《Journal of Artificial Intelligence and Technology》 2023年第1期32-38,共7页
Because of its strong ability to solve problems,evolutionary multitask optimization(EMTO)algorithms have been widely studied recently.Evolutionary algorithms have the advantage of fast searching for the optimal soluti... Because of its strong ability to solve problems,evolutionary multitask optimization(EMTO)algorithms have been widely studied recently.Evolutionary algorithms have the advantage of fast searching for the optimal solution,but it is easy to fall into local optimum and difficult to generalize.Combining evolutionary multitask algorithms with evolutionary optimization algorithms can be an effective method for solving these problems.Through the implicit parallelism of tasks themselves and the knowledge transfer between tasks,more promising individual algorithms can be generated in the evolution process,which can jump out of the local optimum.How to better combine the two has also been studied more and more.This paper explores the existing evolutionary multitasking theory and improvement scheme in detail.Then,it summarizes the application of EMTO in different scenarios.Finally,according to the existing research,the future research trends and potential exploration directions are revealed. 展开更多
关键词 evolutionary multitasking evolutionary algorithm OPTIMIZATION
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BIM Supporting the Development of Multitasks Related with the Structural Project
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作者 Alcínia Zita Sampaio Augusto Martins Gomes +1 位作者 Paulo Manuel Sequeira Gonçalo Ferreira Azevedo 《Journal of Software Engineering and Applications》 2023年第8期397-419,共23页
Building Information Modelling (BIM) is a methodology focused on the centralization and sharing of the project information among all professionals involved, supported on the generation and manipulation of a three-dime... Building Information Modelling (BIM) is a methodology focused on the centralization and sharing of the project information among all professionals involved, supported on the generation and manipulation of a three-dimensional (3D) digital BIM model. This methodology allows a close collaboration between the architect and the structural engineer and an adequate manipulation of the structural BIM model database, on the definition of multitasks. The collaboration allowed between all disciplines, avoid the detection of conflicts and data omission after in the construction place. Two BIM structural design cases were developed, using Revit as the modelling system and Robot as the structural software. Concerning the structural project the interoperability capacity between the software is still a limitation that engineers must be warned of. In the present study, the benefits and limitations identified within the communication and integration of distinct disciplines and on the development of most frequent multitasks normally related with a structural project, were considered. 展开更多
关键词 BIM Structural Project Communication Integration INTEROPERABILITY multitasks
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面向合同信息抽取的动态多任务学习方法
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作者 王浩畅 郑冠彧 赵铁军 《软件学报》 EI CSCD 北大核心 2024年第7期3377-3391,共15页
对于合同文本中要素和条款两类信息的准确提取,可以有效提升合同的审查效率,为贸易各方提供便利化服务.然而当前的合同信息抽取方法一般训练单任务模型对要素和条款分别进行抽取,并没有深挖合同文本的特征,忽略了不同任务间的关联性.因... 对于合同文本中要素和条款两类信息的准确提取,可以有效提升合同的审查效率,为贸易各方提供便利化服务.然而当前的合同信息抽取方法一般训练单任务模型对要素和条款分别进行抽取,并没有深挖合同文本的特征,忽略了不同任务间的关联性.因此,采用深度神经网络结构对要素抽取和条款抽取两个任务间的相关性进行研究,并提出多任务学习方法.所提方法首先将上述两种任务进行融合,构建一种应用于合同信息抽取的基本多任务学习模型;然后对其进行优化,利用Attention机制进一步挖掘其相关性,形成基于Attention机制的动态多任务学习模型;最后针对篇章级合同文本中复杂的语义环境,在前两者的基础上提出一种融合词汇知识的动态多任务学习模型.实验结果表明,所提方法可以充分捕捉任务间的共享特征,不仅取得了比单任务模型更好的信息抽取结果,而且能够有效解决合同文本中要素与条款间实体嵌套的问题,实现合同要素与条款的信息联合抽取.此外,为了验证该方法的鲁棒性,在多个领域的公开数据集上进行实验,结果表明该方法的效果均优于基线方法. 展开更多
关键词 多任务学习 合同文本 信息联合抽取 注意力机制 实体嵌套
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“三心二意”胜过“一心一意”:媒体多任务提升低工作记忆容量者创造力
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作者 周详 张婧婧 +3 位作者 白博仁 翟宏堃 崔虞馨 祖冲 《心理学报》 CSCD 北大核心 2024年第8期1031-1046,共16页
数字时代,媒体多任务已然渗透人类生活方方面面。但以往研究主要探讨其消极影响,忽视媒体多任务暗藏激发创造力的可能。基于创造力的坚持−灵活双通道理论,通过3个仿真行为实验,考察了媒体多任务对创造力的促进作用以及心智游移与工作记... 数字时代,媒体多任务已然渗透人类生活方方面面。但以往研究主要探讨其消极影响,忽视媒体多任务暗藏激发创造力的可能。基于创造力的坚持−灵活双通道理论,通过3个仿真行为实验,考察了媒体多任务对创造力的促进作用以及心智游移与工作记忆容量在其中的中介和调节作用。结果发现:相比非媒体多任务,个体进行媒体多任务时表现出更高的创造力(实验1),其心理机制是媒体多任务诱发更高的心智游移频率,进而提升创造力(实验1和实验2),且这一提升效应只存在于低工作记忆容量组,高工作记忆容量组中则表现为消极影响(实验3)。研究结果对揭示媒体多任务的积极功能,拓展坚持−灵活交互视角以弥补双通道理论平行视角缺陷,帮助不同特质个体有效利用媒体多任务提升创造力均有重要的启示价值。 展开更多
关键词 媒体多任务 创造力 心智游移 工作记忆容量 创造力双通道理论
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融合RoBERTa-GCN-Attention的隐喻识别与情感分类模型
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作者 杨春霞 韩煜 +1 位作者 桂强 陈启岗 《小型微型计算机系统》 CSCD 北大核心 2024年第3期576-583,共8页
在隐喻识别与隐喻情感分类任务的联合研究中,现有多任务学习模型存在对隐喻语料中的上下文语义信息和句法结构信息提取不够准确,并且缺乏对粗细两种粒度信息同时捕捉的问题.针对第1个问题,首先改进了传统的RoBERTa模型,在原有的自注意... 在隐喻识别与隐喻情感分类任务的联合研究中,现有多任务学习模型存在对隐喻语料中的上下文语义信息和句法结构信息提取不够准确,并且缺乏对粗细两种粒度信息同时捕捉的问题.针对第1个问题,首先改进了传统的RoBERTa模型,在原有的自注意力机制中引入上下文信息,以此提取上下文中重要的隐喻语义特征;其次在句法依存树上使用图卷积网络提取隐喻句中的句法结构信息.针对第2个问题,使用双层注意力机制,分别聚焦于单词和句子层面中对隐喻识别和情感分类有贡献的特征信息.在两类任务6个数据集上的对比实验结果表明,该模型相比基线模型性能均有提升. 展开更多
关键词 隐喻识别 情感分类 多任务学习 RoBERTa 图卷积网络 注意力机制
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面向类不均衡数据的多任务博弈概率分类向量机
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作者 潘海洋 李丙新 +1 位作者 郑近德 童靳于 《机电工程》 CAS 北大核心 2024年第3期430-437,共8页
在工程实际中获取的故障样本往往会呈现不均衡特点,同时传统的分类模型也会存在局限性。针对这些问题,基于稀疏贝叶斯理论、模糊隶属度等理论,提出了一种多任务博弈概率分类向量机(MGPCVM)分类方法。首先,在MGPCVM的目标函数中,设计了... 在工程实际中获取的故障样本往往会呈现不均衡特点,同时传统的分类模型也会存在局限性。针对这些问题,基于稀疏贝叶斯理论、模糊隶属度等理论,提出了一种多任务博弈概率分类向量机(MGPCVM)分类方法。首先,在MGPCVM的目标函数中,设计了博弈因子,将不同类样本质心间的博弈信息赋予每个样本特定的样本质心敏感值,以解决传统分类器对不平衡数据集分类表现较差的问题;然后,在贝叶斯框架理论下,采用截断高斯先验分布的方法,使样本参数的正负与对应的标签信息相一致,且使样本质心敏感值产生了稀疏估计;最后,将MGPCVM方法应用于两种不同实验平台采集的滚动轴承实验数据处理,进行了故障诊断有效性验证。研究结果表明:在不同的不平衡比(IR)下,MGPCVM方法的准确率均保持在95%以上,相对于支持向量机(SVM)、概率分类向量机(PCVM)等方法提升了4%~8%;与典型向量式分类方法相比,MGPCVM方法可以在不平衡数据条件下表现出优越的分类性能,适用于实际工况中数据失衡的分类问题。 展开更多
关键词 滚动轴承 故障诊断 多任务博弈概率分类向量机 支持向量机 概率分类向量机 不均衡比 故障分类模型
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多任务优化算法及应用研究综述
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作者 武越 丁航奇 +5 位作者 何昊 毕顺杰 江君 公茂果 苗启广 马文萍 《计算机应用》 CSCD 北大核心 2024年第5期1338-1347,共10页
进化多任务优化(EMTO)是进化计算中一种新型方法,它可以同时解决多个相关的优化任务,并通过任务之间的知识转移增强每个任务的优化。近年来,越来越多的进化多任务优化相关研究致力于利用它强大的并行搜索能力和降低计算成本的潜力优化... 进化多任务优化(EMTO)是进化计算中一种新型方法,它可以同时解决多个相关的优化任务,并通过任务之间的知识转移增强每个任务的优化。近年来,越来越多的进化多任务优化相关研究致力于利用它强大的并行搜索能力和降低计算成本的潜力优化各种问题,并且EMTO已应用于各种各样的实际场景当中。从EMTO的原理、核心设计、应用以及挑战四个方面对EMTO的算法及应用进行了讨论。首先介绍了EMTO的大致分类,分别从两个层次、四个方面介绍,包括单种群多任务、多种群多任务、辅助任务形式以及多形式任务形式;其次介绍EMTO的核心组件设计,包括任务构建以及知识转移;最后对它的各种应用场景进行介绍,并对今后研究做了总结与展望。 展开更多
关键词 进化多任务优化 单种群多任务 多种群多任务 多形式任务 知识转移
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中小学生的媒体多任务行为及其对抑郁情绪的影响:基本心理需要和自我控制的中介作用
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作者 陈嫣 陶婷 +2 位作者 王利刚 樊春雷 高文斌 《中国健康心理学杂志》 2024年第7期1109-1114,共6页
目的:探索中小学生媒体多任务行为与抑郁的关系,并明确其与自我控制、基本心理需求的关系。方法:通过问卷调查方式,采用随机抽样方法,在成都及重庆城区中小学校收集了有效问卷总共2147份。使用媒体多任务问卷测查媒体多任务使用情况,使... 目的:探索中小学生媒体多任务行为与抑郁的关系,并明确其与自我控制、基本心理需求的关系。方法:通过问卷调查方式,采用随机抽样方法,在成都及重庆城区中小学校收集了有效问卷总共2147份。使用媒体多任务问卷测查媒体多任务使用情况,使用儿童抑郁量表、青少年自我控制双系统量表和基本心理需要满足量表测查个体抑郁水平、冲动控制性及基本心理需要情况。结果:①媒体多任务行为与抑郁得分呈正相关(r=0.341,P<0.01),媒体多任务行为与基本心理需要(r=-0.352,P<0.01)、自我控制呈负相关(r=-0.262,P<0.01)。②中介效应结果表明,中小学生媒体多任务行为对抑郁情绪的直接效应显著,效应值为0.045,基本心理需要和自我控制在媒体多任务行为与抑郁之间起到部分中介作用,效应值分别为0.038和0.007,中介效应占比61.290%和11.290%;基本心理需要的中介效应显著大于自我控制。结论:中小学生媒体多任务行为能预测抑郁;控制力强,基本心理需要满足高的个体倾向于进行单一媒体操作,抑郁风险低。 展开更多
关键词 中小学生 媒体多任务行为 抑郁 自我控制 基本心理需要
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一种基于多维表示的汉字识别方案
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作者 陈成 姜明 张旻 《软件工程》 2024年第8期24-29,共6页
针对复杂场景下汉字特征提取难的问题,提出了一种基于多维特征表示的汉字识别方案。首先,提出一种融合空间信息的关键笔形特征提取方法,能够利用少量关键特征实现汉字的唯一识别;其次,通过多任务网络提取多维特征,增强特征提取能力,从... 针对复杂场景下汉字特征提取难的问题,提出了一种基于多维特征表示的汉字识别方案。首先,提出一种融合空间信息的关键笔形特征提取方法,能够利用少量关键特征实现汉字的唯一识别;其次,通过多任务网络提取多维特征,增强特征提取能力,从而提高汉字识别的准确性;最后,应用字符相似度算法消除噪声,优化识别结果。实验结果表明,相较于可插拔的部首感知分支(PRAB)模型,本方案在场景数据集、网页数据集、文本数据集和手写数据集中的性能分别提升了1.62百分点、1.09百分点、0.15百分点和1.27百分点,证明了该方案的有效性。 展开更多
关键词 汉字识别 特征提取 关键笔形 多任务网络
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基于机器学习的演化多任务优化框架 被引量:1
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作者 麦伟杰 刘伟莉 钟竞辉 《计算机学报》 EI CAS CSCD 北大核心 2024年第1期29-51,共23页
演化多任务优化是近年来计算智能领域的研究热点之一,其原理是通过任务间的知识转移提高演化算法同时求解多个任务的效率.由于任务间相似性对促进任务之间的正向知识转移具有重要的影响,因此,如何度量任务间的相似性成为了重点研究方向... 演化多任务优化是近年来计算智能领域的研究热点之一,其原理是通过任务间的知识转移提高演化算法同时求解多个任务的效率.由于任务间相似性对促进任务之间的正向知识转移具有重要的影响,因此,如何度量任务间的相似性成为了重点研究方向之一.目前,演化多任务优化在处理两个任务时,辅助任务的选取仅限于两者之一,且在处理超多任务时对任务间知识的转移缺乏灵活性.为此,本文提出一个基于机器学习的演化多任务优化框架,命名为MaTML.该框架联合所有任务关联的子种群形成一个统一的初始化种群,利用目标任务的技能因子及其对应的种群个体分别构建标签和训练集,应用十折交叉法拟合模型,并运用模型预测与目标任务相似的个体以组成辅助种群,从而促进演化优化中的正向知识转移.本文提出的算法能够在动态的种群个体中找到目标任务的辅助种群,不仅可以为三个或以上的多任务优化灵活地选取相似辅助任务,而且解决了当任务数量为两个时有效地选择辅助任务的问题.通过与现阶段的多任务算法和超多任务算法分别在CEC2017问题测试集和WCCI2020SO问题测试集进行比较,实验结果证实MaTML在优化多任务问题时具有更优或竞争性的性能.此外,文中还详细研究了MaTML的计算资源、模型性能、模型稳定性以及相关组件.最后,本文还基于真实问题的测试进一步验证了MaTML的有效性. 展开更多
关键词 演化多任务优化 机器学习 任务间相似性 知识转移 辅助任务
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多模态命名实体识别方法研究进展 被引量:1
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作者 王海荣 徐玺 +1 位作者 王彤 荆博祥 《郑州大学学报(工学版)》 CAS 北大核心 2024年第2期60-71,共12页
为了解决多模态命名实体识别(MNER)研究中存在的文本特征语义不足、视觉特征语义缺失、图文特征融合困难等问题,多模态命名实体识别方法相继被提出。首先,总结了多模态命名实体识别方法的整体框架以及各部分常用的技术,随后对其进行梳... 为了解决多模态命名实体识别(MNER)研究中存在的文本特征语义不足、视觉特征语义缺失、图文特征融合困难等问题,多模态命名实体识别方法相继被提出。首先,总结了多模态命名实体识别方法的整体框架以及各部分常用的技术,随后对其进行梳理并分类为基于BiLSTM的MNER方法和基于Transformer的MNER方法,并根据模型结构将其划分为前融合模型、后融合模型、Transformer单任务模型、Transformer多任务模型等4类模型结构。其次,在Twitter-2015、Twitter-2017 2个数据集上,分别对这2类方法进行实验,结果表明:多特征协同表示能增强各模态特征的语义,多任务学习能够促进模态特征融合或者结果融合,从而提升MNER的准确性。建议在MNER的未来研究中,着重关注通过多特征协同表示来增强模态语义,通过多任务学习促进模态特征融合或结果融合等方向的研究。 展开更多
关键词 多模态命名实体识别 TRANSFORMER BiLSTM 多模态融合 多任务学习
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优化场景视角下的进化多任务优化综述
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作者 赵佳伟 陈雪峰 +3 位作者 冯亮 候亚庆 朱泽轩 Ong Yew-Soon 《计算机应用》 CSCD 北大核心 2024年第5期1325-1337,共13页
随着优化问题变得日益复杂,传统的进化算法由于计算成本高昂和适用性有限而面临挑战。为了克服这些挑战,基于知识迁移的进化多任务优化(EMTO)算法应运而生,它的核心思想是通过跨任务的知识共享,同时解决多个优化问题,旨在提高进化算法... 随着优化问题变得日益复杂,传统的进化算法由于计算成本高昂和适用性有限而面临挑战。为了克服这些挑战,基于知识迁移的进化多任务优化(EMTO)算法应运而生,它的核心思想是通过跨任务的知识共享,同时解决多个优化问题,旨在提高进化算法在应对复杂优化场景的效率。全面总结了当前进化多任务优化研究的进展,与已有综述文章相比,从不同的研究视角进行深入探讨,并指出了现有文献中对优化场景视角分析的缺失。鉴于此,从优化问题的应用场景出发,对适用于进化多任务优化的场景及其基本解决策略进行了系统性的阐述,以帮助研究人员准确地根据具体应用需求选择合适的研究方法。此外,深入讨论进化多任务优化当前面临的挑战和未来的研究方向,旨在为未来的研究提供指导和启示。 展开更多
关键词 进化算法 进化多任务优化 知识迁移 复杂优化问题
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