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Spectrum Prediction Based on GAN and Deep Transfer Learning:A Cross-Band Data Augmentation Framework

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China Communications 2021年第1期18卷 18-32页

作者： Fandi Lin Jin Chen Guoru Ding Yutao Jiao Jiachen Sun Haichao Wang College of Communications Engineering Army Engineering UniversityNanjing 210007China

This paper investigates the problem of data scarcity in spectrum prediction.A cognitive radio equipment may frequently switch the target frequency as the electromagnetic environment changes.The previously trained model for prediction often cannot maintain a good performance when facing small amount of historical data of the new target frequency.Moreover,the cognitive radio equipment usually implements the dynamic spectrum access in real time which means the time to recollect the data of the new task frequency band and retrain the model is very limited.To address the above issues,we develop a crossband data augmentation framework for spectrum prediction by leveraging the recent advances of generative adversarial network(GAN)and deep transfer learning.Firstly,through the similarity measurement,we pre-train a GAN model using the historical data of the frequency band that is the most similar to the target frequency band.Then,through the data augmentation by feeding the small amount of the target data into the pre-trained GAN,temporal-spectral residual network is further trained using deep transfer learning and the generated data with high similarity from GAN.Finally,experiment results demonstrate the effectiveness of the proposed framework.

关键词： cognitive radio cross-band spectrum prediction deep transfer learning generative adversarial network cross-band data augmentation framework

UAV-Assisted Dynamic Avatar Task Migration for Vehicular Metaverse Services: A Multi-Agent Deep Reinforcement Learning Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 430-445页

作者： Jiawen Kang Junlong Chen Minrui Xu Zehui Xiong Yutao Jiao Luchao Han Dusit Niyato Yongju Tong Shengli Xie IEEE School of Automation Guangdong University of TechnologyGuangzhou 510006China 111 Center for Intelligent Batch Manufacturing based on IoT Technology Guangzhou 510006China Key Laboratory of Intelligent Information Processing and System Integration of IoT Ministry of EducationGuangzhou 510006China School of Computer Science and Engineering Nanyang Technological UniversitySingaporeSingapore Pillar of Information Systems Technology and Design Singapore University of Technology and DesignSingaporeSingapore College of Communication Engineering Army Engineering University of PLANanjing 210007China National Natural Science Foundation of China Beijing 100085China Key Laboratory of Intelligent Detection and IoT in Manufacturing Ministry of EducationGuangzhou 510006China Guangdong Key Laboratory of IoT Information Technology Guangzhou 510006China

Avatars, as promising digital representations and service assistants of users in Metaverses, can enable drivers and passengers to immerse themselves in 3D virtual services and spaces of UAV-assisted vehicular Metaverses. However, avatar tasks include a multitude of human-to-avatar and avatar-to-avatar interactive applications, e.g., augmented reality navigation,which consumes intensive computing resources. It is inefficient and impractical for vehicles to process avatar tasks locally. Fortunately, migrating avatar tasks to the nearest roadside units(RSU)or unmanned aerial vehicles(UAV) for execution is a promising solution to decrease computation overhead and reduce task processing latency, while the high mobility of vehicles brings challenges for vehicles to independently perform avatar migration decisions depending on current and future vehicle status. To address these challenges, in this paper, we propose a novel avatar task migration system based on multi-agent deep reinforcement learning(MADRL) to execute immersive vehicular avatar tasks dynamically. Specifically, we first formulate the problem of avatar task migration from vehicles to RSUs/UAVs as a partially observable Markov decision process that can be solved by MADRL algorithms. We then design the multi-agent proximal policy optimization(MAPPO) approach as the MADRL algorithm for the avatar task migration problem. To overcome slow convergence resulting from the curse of dimensionality and non-stationary issues caused by shared parameters in MAPPO, we further propose a transformer-based MAPPO approach via sequential decision-making models for the efficient representation of relationships among agents. Finally, to motivate terrestrial or non-terrestrial edge servers(e.g., RSUs or UAVs) to share computation resources and ensure traceability of the sharing records, we apply smart contracts and blockchain technologies to achieve secure sharing management. Numerical results demonstrate that the proposed approach outperforms the MAPPO approach by around 2% and

关键词： Avatar blockchain metaverses multi-agent deep reinforcement learning transformer UAVs

三孔法经腹膜外腹腔镜下根治性前列腺切除术治疗局限性前列腺癌效果分析

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河南外科学杂志 2022年第1期28卷 9-12页

作者：李长建焦玉涛新乡医学院第三附属医院泌尿外科新乡453003

目的探讨三孔法经腹膜外腹腔镜下根治性前列腺切除术(ELRP)治疗局限性前列腺癌的效果。方法回顾性分析新乡医学院第三附属医院泌尿外科2018-01—2019-06行ELRP治疗的93例局限性前列腺癌患者的临床资料。采用三孔法ELRP治疗的(49例)为观... 详细信息

目的探讨三孔法经腹膜外腹腔镜下根治性前列腺切除术(ELRP)治疗局限性前列腺癌的效果。方法回顾性分析新乡医学院第三附属医院泌尿外科2018-01—2019-06行ELRP治疗的93例局限性前列腺癌患者的临床资料。采用三孔法ELRP治疗的(49例)为观察组,采用四孔法ELRP治疗的44例为对照组。对比2组围术期指标、术前、术后1 d、术后3 d血清应激反应指标肾上腺素(E)、去甲肾上腺素(NE)、皮质醇(Cor)、血糖(Glu),胰岛素样生长因子1(IGF-1),游离前列腺特异性抗原(fPSA)水平及术后12个月尿失禁发生率、生化复发率。结果观察组手术时间短于对照组,术中出血量低于对照组,差异有统计学意义(P0.05);术后1 d、术后3 d 2组血清E、NE、Cor、Glu水平高于术前,但观察组低于对照组,差异有统计学意义(P0.05);2组术后12个月尿失禁发生率、生化复发率比较,差异无统计学意义(P>0.05)。结论三孔法、四孔法ELRP治疗局限性前列腺癌患者效果相当,但三孔法具有创伤小、手术时间短、出血少、应激反应轻等优势。

关键词：三孔法四孔法腹膜外根治性前列腺切除术局限性前列腺癌

世界医学科学研究领域重心转移规律--以国际医学科学奖为例

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科学学与科学技术管理 2023年第5期44卷 3-14页

作者：孙玉涛卢凤娇焦爽汪宗龙大连理工大学经济管理学院辽宁大连116024

为推进“健康中国”建设,响应坚决打赢新冠疫情防控攻坚战的要求,我国迫切需要重视国际医学科学领域发展前沿和趋势,有预见性的开展科研攻关。文章运用生命科学和医学领域国际奖项构建衡量医学领域国际影响力的获奖指数(指数与比例),运... 详细信息

为推进“健康中国”建设,响应坚决打赢新冠疫情防控攻坚战的要求,我国迫切需要重视国际医学科学领域发展前沿和趋势,有预见性的开展科研攻关。文章运用生命科学和医学领域国际奖项构建衡量医学领域国际影响力的获奖指数(指数与比例),运用1901-2021年649位获奖者及其获奖成果相关数据,对国际医学三大领域及其下属46个子领域进行分析,揭示121年间世界医学科学研究领域重心阶段性转移规律,并进行趋势预测。研究发现:(1)世界医学科学三大领域内部呈现“小聚焦,大分散”的多极化发展趋势,少数子领域始终占据研究前沿,其他子领域呈现阶段性显现特征;(2)世界医学科学三大领域间重心由非传染性疾病与生物化学两者相持,转向重点关注生物化学领域,传染病呈现阶段性显现特征;(3)预测世界医学科学研究领域内及领域间均会呈现不同程度的重心偏移现象。

关键词：健康中国医学科学研究领域重心国际奖项医学获奖指数

Air pollution may increase the sleep apnea severity:A nationwide analysis of smart device-based monitoring

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The Innovation 2023年第6期4卷 69-75页

作者： Qingli Zhang Hong Wang Xinlei Zhu Anni Li Cong Liu yutao Guo Haidong Kan Renjie Chen School of Public Health Shanghai Institute of Infectious Disease and BiosecurityKey Lab of Public Health Safety of the Ministry of Education and NHC Key Lab of Health Technology AssessmentFudan UniversityShanghai 200032China Minitry of Education-Shanghai Key Laboratory of Children's Environmental Health Xinhua Hospital ffliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China Sixth Medical Center Chinese PL A General HospitalBejing 100048China Chinese PLA Medical College Beijing 100039China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Obstructive sleep apnea(OSA)can lead to sleep deprivation,accidents,and cardiovascular diseases.However,research on the short-term effects of air pollutants on OSA severity is limited and inconsistent.We conducted a novel case time series analysis using a nationwide dataset among Huawei smart device users to assess the association between air pollution and OSA severity in a population at moderate-to-severe risk of OSA.Fixed-effects regression models were used to assess the associations between air pollution and the risk of OSA exacerbation,apnea-hypopnea index(AH),and oxygen saturation.A total of 51,842 participants who were at moder-ate-tosevere risk of OSA(mean age[SD]:45.4[11.0],95.5%male)were included,with 6,232,056 person-days of monitoring.The as sociations of fine particulate matter,nitrogen dioxide,carbon monoxide,and sulfur dioxide with OSA severity could occur during the sleep period,and last for 2 days.An increase of 1 interquartile range in the moving average concentrations of air pollution during the sleep period and the 2 previous days was associated with a 1.14%-4.31%increase in the risk of OSA exacerbation,an increase in AHI by 0.05-0.17 events/h,and a decrease in oxygen saturation(%)by 0.003-0.014.The exposure-response curves were almost linear.The associations between air pollutants and OSA were consistently stronger in participants aged 45 years or older.By virtue of the smart device-based technology,this largescale,nationwide,longitudinal study provides compelling evidence that short-term exposure to air pollution may worsen sleep apnea.Our findings highlight the significance of ongoing efforts to improve air quality in mitigating OSA severity and the relevant disease burden in an aging era.

关键词： severity sleep pollution

Multi-element B-site substituted perovskite ferroelectrics exhibit enhanced electrocaloric effect

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Science China(Technological Sciences) 2023年第4期66卷 1119-1128页

作者： DU FeiHong SONG ZhiWu XU yutao HAN DongLin LI Qiang ZHENG ShanYu SHEN JiaHe QIAN XiaoShi Interdisciplinary Research Centre School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Zhejiang Research Institute of Chemical Industry Hangzhou 310023China

Electrocaloric(EC)refrigeration holds the promise to achieve next-generation refrigeration technology that can be efficiently powered by electricity.BaTiO_(3)(BT)-based ferroelectric materials are attractive owing to their environmentally benign compositions,large polarization,and existing manufacturing method for multilayer ceramic capacitors(MLCC),which have stimulated intensive research efforts on these materials.Here,we report an enhanced electrocaloric effect(ECE)and the refrigeration capacity of multi-element B-site substituted BT-based ceramics.The compositions of the proposed Ba(Hf_(x)Sn_(x)Zr_(y))-Ti_(1-2x-y)O_(3)(BHSZT)ceramics were selected by fine-tuning each substituent against Titanium ions Ti^(4+),aiming to their respective morphotropic phase boundary(MPB).The BHSZT exhibited an ECE that is greater than that of the single-element substituted BaTiO_(3) ceramics by at least 50%,reaching an adiabatic temperature change of above 1.7 K under 40 kV/cm.Meanwhile,the operating temperature window of the BHSZT ceramics is observed to cover the room temperature,which is a critical feature that allows the device implementation in our daily life.The multi-element substitution improved the overall ECE performances,providing a high degree of freedom for polar reorientation and hence the large polar entropy that could be utilized by the external electric field.

关键词： ferroelectrics electrocalorics Ceramics

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海上交通资源与船舶污染环境承载力预测模型

中国航海 2013年第1期36卷 109-114页

作者：康与涛许乐平焦宇上海海事大学海洋环境与工程学院上海201306

近年来我国港口对资源与环境的需求发生了深刻的变化,给资源环境承载力带来新的挑战。为此提出海上交通资源与船舶污染环境承载力概念。通过海上交通资源和船舶污染环境承载现状评估,构建了评价海上交通资源和船舶污染环境承载力指标体... 详细信息

近年来我国港口对资源与环境的需求发生了深刻的变化,给资源环境承载力带来新的挑战。为此提出海上交通资源与船舶污染环境承载力概念。通过海上交通资源和船舶污染环境承载现状评估,构建了评价海上交通资源和船舶污染环境承载力指标体系,分别建立了海上交通资源承载力和船舶污染环境承载力两个计量分析预警模型及其情景分析预测,形成海上交通资源与船舶污染环境承载力综合预测预警系统,并对未来海上交通资源与船舶污染承载状态作出预测预警。验证结果表明,海上交通资源和船舶污染环境承载力系统较准确地评估和预测了当前和未来海上交通资源和船舶污染的承载力状况,为航运资源的科学规划和可持续发展提供技术支撑。

关键词：水路运输海上交通船舶污染承载力预测预警

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复杂电磁环境下频谱智能管控技术探讨

航空学报 2021年第4期42卷 194-206页

作者：丁国如孙佳琛王海超焦雨涛陆军工程大学通信工程学院南京210007

作为国土空间的重要组成,电磁频谱空间呈现出环境错综复杂、目标类型多样、用频行为多变等新挑战,导致频谱安全问题日益严峻。面向复杂电磁环境下频谱秩序安全、频谱对抗安全和频谱共享安全等需求,基于人工智能的频谱管控成为电磁频谱... 详细信息

作为国土空间的重要组成,电磁频谱空间呈现出环境错综复杂、目标类型多样、用频行为多变等新挑战,导致频谱安全问题日益严峻。面向复杂电磁环境下频谱秩序安全、频谱对抗安全和频谱共享安全等需求,基于人工智能的频谱管控成为电磁频谱领域的重要研究方向,存在着具有挑战性的基础理论问题和关键技术难题。首先,调研了复杂电磁环境下频谱智能管控的国家战略需求,然后,提炼了智能频谱管控的科学意义与技术挑战,进一步从频谱管控模型机理、频谱态势感知、频谱行为推理、频谱安全决策和频谱管控应用系统等5个方面梳理国内外研究现状,并分析了相关发展动态及研究趋势。

关键词：复杂电磁环境频谱管控人工智能信息流无人机群物联网

侧隙对摆线针轮传动啮合力与摩擦功耗的影响分析

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机械传动 2022年第1期46卷 110-114页

作者：李宇涛金守峰焦航侯一泽西安工程大学机电工程学院陕西西安710048

啮合侧隙是影响摆线针轮副承载能力、摩擦功耗、振动噪声等传动性能的关键因素之一。利用摆线针轮传动原理,建立了考虑侧隙的摆线轮与针齿啮合力及摩擦功耗分析模型,并引入比较系数,描述了侧隙对摆线轮针齿啮合副接触力和摩擦功耗的影... 详细信息

啮合侧隙是影响摆线针轮副承载能力、摩擦功耗、振动噪声等传动性能的关键因素之一。利用摆线针轮传动原理,建立了考虑侧隙的摆线轮与针齿啮合力及摩擦功耗分析模型,并引入比较系数,描述了侧隙对摆线轮针齿啮合副接触力和摩擦功耗的影响。分析表明,侧隙会显著改变参与接触的针齿数量,从而改变接触力峰值和摩擦功耗,即侧隙增大会导致接触力峰值显著增大,但摩擦功耗会略有降低。该方法可为评估初始及磨损后侧隙对轮齿接触特性的影响机制提供简便的理论方法。

关键词：摆线针轮啮合间隙轮齿接触力分析摩擦功耗