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Transmission Energy Allocation for Over-the-Air Computation with Energy Harvesting

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Journal of Communications and Information Networks 2024年第2期9卷 126-136页

作者： Siyao Zhang Zixiang Ren Xinmin Li yin long Jie Xu Shuguang Cui School of Computer Science and Technology Southwest University of Science and TechnologyMianyang 621010China Shenzhen Future Network of Intelligence Institute(FNii-Shenzhen) The Chinese University of Hong KongShenzhenGuangdong 518172China School of Information Science and Technology University of Science and Technology of ChinaHefei 230027China FNii-Shenzhen The Chinese University of Hong KongShenzhenGuangdong 518172China College of Computer Science Chengdu UniversityChengdu 610100China School of Science and Engineering FNii-Shenzhenand Guangdong Provincial Key Laboratory of Future Networks of IntelligenceThe Chinese University of Hong KongShenzhenGuangdong 518172China

Over-the-air computation(AirComp)has recently emerged as a promising multiple-access technique for fast wireless data aggregation(WDA)from distributed wireless devices(WDs). This paper investigates an energy harvesting (EH) AirComp system, in which multiple EH-powered single-antenna WDs simultaneously send wireless signals to a single-antenna access point (AP) with conventional energy supply for WDA via AirComp. Under this setup, we minimize the average computation mean square error(MSE)over a particular time period, by jointly optimizing the transmit energy allocation at the WDs and the AirComp denoising factors at the AP over time, subject to the energy causality constraints at individual WDs. First, we consider the offline scenario by assuming that the energy state information(ESI)and channel state information (CSI) are non-causally known at the beginning of the period, in which the formulated average MSE minimization corresponds to a non-convex optimization problem. We present a high-quality converged solution by using the techniques of alternating optimization and convex optimization. It is shown that for each WD,if the EH rate is sufficiently high,then the channel inversion power allocation is adopted;while if the EH rate is low, then all the harvested energy should be used up for transmission with proper energy allocation over time. Next, we consider the online scenario with causal ESI and CSI,in which the MSE minimization becomes a stochastic optimization *** this scenario, we present an offline-inspired online algorithm to obtain efficient online energy allocation designs by utilizing the obtained offline solutions. Finally,numerical results show that the proposed designs significantly outperform two benchmark schemes with power-halving and full-power transmission,respectively.

关键词： over-the-air computation(AirComp) power allocation energy harvesting(EH) optimization

Trade-off analyses between food provision and soil conservation service of Grain for Green Program in Mountainous Area

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International Soil and Water Conservation Research 2024年第1期12卷 43-53页

作者： Yawen Li Yuxiang Li Xingwu Duan Zhongyin Cai Ya Li Baiyun He long yin Institute of International River and Eco-security Yunnan UniversityKunming650091PR China Yunnan Key Laboratory of International Rivers and Trans-boundary Eco-security Kunming650091PR China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085PR China University of Chinese Academy of Sciences Beijing100049PR China

The Grain for Green Program and soil and water conservation engineering initiatives are crucial for controlling erosion in steep-slope ***,it is still unclear how these two management methods should be carried out in respect to the situation in mountainous ***,taking a typical mountainous area in southwest China as an example,we simulated six scenarios in order to compare the food provisioning service(FPS)and soil conservation service of the Grain for Green Program(converting to grassland)and Construction Measures(converting to sloping terrace)under different *** showed that when farmland with a>25°slope was converted into grassland,the amount of soil erosion(M)decreased by 21.0%,while FPS decreased by only 0.7%.However,when farmland with a>25°slope was converted into sloping terrace,M decreased by 31.3%while FPS increased by 18.7%.With the increases of farmland slope ranges in the Construction Measures scenario,M gradually decreased and FPS gradually *** when farmland>15°was converted into sloping terrace,M decreased by 63.9%and FPS increased by 52.7%.Furthermore,the trade-offs of Construction Measures are lower than that of Grain for Green on different slope ***,we conclude that Construction Measures are a more suitable method in mountainous areas than the Grain for Green,and we suggest that further research be conducted to consider the ecological risks of construction engineering measures.

关键词： Soil erosion Grain for green Construction measures Mountainous areas

Metal-N_(4)model single‐atom catalyst with electroneutral quadri‐pyridine macrocyclic ligand for CO_(2)electroreduction

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Carbon Energy 2024年第8期6卷 122-133页

作者： Jian‐Zhao Peng yin‐long Li Yao‐Ti Cheng Fu‐Zhi Li Bo Cao Qing Wang Xian Yue Guo‐Tao Lai Yang‐Gang Wang Jun Gu Department of Chemistry Southern University of Science and TechnologyShenzhenGuangdongChina Institute for Catalysis Hokkaido UniversitySapporoJapan

Metal–N–C single‐atom catalysts,mostly prepared from pyrolysis of metalorganic precursors,are widely used in heterogeneous *** metal sites with diverse local structures coexist in this type of material and it is challenging to characterize the local structure,a reliable structure–property relationship is difficult to *** macrocyclic complexes adsorbed on carbon support are well‐defined models to mimic the singleatom ***–N_(4)site with four electroneutral pyridine‐type ligands embedded in a graphene layer is the most commonly proposed structure of the active site of single‐atom catalysts,but its molecular counterpart has not been *** this work,we synthesized the conjugated macrocyclic complexes with a metal center(Co,Fe,or Ni)coordinated with four electroneutral pyridinic ligands as model catalysts for CO_(2)*** comparison,the complexes with anionic quadri‐pyridine macrocyclic ligand were also *** Co complex with the electroneutral ligand expressed a turnover frequency of CO formation more than an order of magnitude higher than that of the Co complex with the anionic *** ab initio molecular dynamics simulations based on the well‐defined structures of the model catalysts indicate that the Co complex with the electroneutral ligand possesses a stronger ability to mediate electron transfer from carbon to CO_(2).

关键词： ab initio molecular dynamics CO_(2)reduction electrocatalysis model catalyst single‐atom catalyst

区域应急合作何以化解“属地—跨界”冲突——基于长三角地区开展危机学习的纵向案例研究

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甘肃行政学院学报 2024年第2期 76-88,127页

作者：龙吟华南理工大学公共管理学院广州510641

区域应急合作是应急管理中的重要一环,却一直面临属地管理与跨界危机的矛盾难题。本文以危机学习为理论视角,通过对长三角地区区域应急合作的纵向案例分析,探讨危机学习如何成为化解“属地—跨界”冲突的关键钥匙,刻画区域应急合作政府... 详细信息

区域应急合作是应急管理中的重要一环,却一直面临属地管理与跨界危机的矛盾难题。本文以危机学习为理论视角,通过对长三角地区区域应急合作的纵向案例分析,探讨危机学习如何成为化解“属地—跨界”冲突的关键钥匙,刻画区域应急合作政府开展危机学习的驱动要素和运作机制。研究发现:跨界危机的频繁触发、中央纵向的目标设定、地方横向的资源调度和合法性欠缺的规则补充共同组成区域合作政府开展危机学习的驱动要素。在此基础上,危机学习化解“属地—跨界”冲突的关键在于利益导向的资源分配机制、技术导向的信息共享机制、结构导向的组织重塑机制、过程导向的行为调整机制和制度导向的政策变革机制,实现区域应急深入合作,并且机制之间组合构成单环学习和双环学习模式,呈现相互耦合的内在逻辑。相关研究从危机学习的视角重新审视了实现区域应急合作的有效路径,丰富了危机学习的理论研究图谱。

关键词：区域应急合作危机学习跨界危机属地管理长三角

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局部一致性主动学习的源域无关开集域自适应

软件学报 2024年第4期35卷 1651-1666页

作者：王帆韩忠义苏皖尹义龙山东大学软件学院山东济南250101

无监督域自适应在解决训练集(源域)和测试集(目标域)分布不一致的问题上已经取得了一定的成功.在面向低能耗场景和开放动态任务环境时,在资源约束和开放类别出现的情况下,现有的无监督域自适应方法面临着严峻的挑战.源域无关开集域自适... 详细信息

无监督域自适应在解决训练集(源域)和测试集(目标域)分布不一致的问题上已经取得了一定的成功.在面向低能耗场景和开放动态任务环境时,在资源约束和开放类别出现的情况下,现有的无监督域自适应方法面临着严峻的挑战.源域无关开集域自适应(SF-ODA)旨在将源域模型中的知识迁移到开放类出现的无标签目标域,从而在无源域数据资源的限制下辨别公共类和检测开放类.现有的源域无关开集域自适应的方法聚焦于设计准确检测开放类别的源域模型或增改模型的结构.但是,这些方法不仅需要额外的存储空间和训练开销,而且在严格的隐私保护场景下难以实现.提出了一个更加实际的场景:主动学习的源域无关开集域自适应(ASF-ODA),目标是基于一个普通训练的源域模型和少量专家标注的有价值的目标域样本来实现鲁棒的迁移.为了达成此目标,提出了局部一致性主动学习(LCAL)算法.首先,利用目标域中局部特征标签一致的特点,LCAL设计了一种新的主动选择方法:局部多样性选择,来挑选更有价值的阈值模糊样本来促进开放类和公共类分离.接着,LCAL基于信息熵初步筛选出潜在的公共类集合和开放类集合,并利用第一步得到的主动标注样本对这两个集合进行匹配纠正,得到两个对应的可信集合.最后,LCAL引入开集损失和信息最大化损失来进一步促使公共类和开放类分离,引入交叉熵损失来实现公共类的辨别.在Office-31、Office-Home和VisDA-C这3个公开的基准数据集上的大量实验表明:在少量有价值的目标域样本的帮助下,LCAL不仅显著优于现有的源域无关开集域自适应方法,还大幅度超过了现有的主动学习方法的表现,在某些迁移任务上可以提升20%.

关键词：资源约束开集识别源域无关域自适应开集域自适应主动学习

Engineering The Neck Hinge Reshapes The Processive Movement of Kinesin-3

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生物化学与生物物理进展 2024年第10期51卷 2730-2740页

作者： LI Dong REN Jin-Qi SONG yin-long LIANG Xin FENG Wei Key Laboratory of Biomacromolecules(CAS) National Laboratory of BiomacromoleculesCAS Center for Excellence in BiomacromoleculesInstitute of BiophysicsChinese Academy of SciencesBeijing 100101China School of Life Sciences Tsinghua UniversityBeijing 100084China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China

Objective In kinesin-3,the neck coil correlates with the following segments to form an extended neck that contains a characteristic hinge diverse from a proline in KIF13B to a long flexible linker in *** function of this neck hinge for controlling processive movement,however,remains *** We made a series of modifications to the neck hinges of KIF13B and KIF1A and tested their movement using a single-molecule motility *** In KIF13B,the insertion of flexible residues before or after the proline differentially impacts the processivity or velocity,while the removal of this proline increases the *** KIF1A,the deletion of entire flexible neck hinge merely enhances the *** engineering of these hinge-truncated necks of kinesin-3 into kinesin-1 similarly boosts the processive movement of *** The neck hinge in kinesin-3 controls its processive movement and proper modifications tune the motor motility,which provides a novel strategy to reshape the processive movement of kinesin motors.

关键词： intracellular transport molecular motor kinesin-3 neck hinge processive movement

考虑夯锤姿态特性的夯沉量单目视觉测量方法研究

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岩土力学 2024年第3期45卷 927-938页

作者：高乔裕金银龙刘全张宏阳梅龙喜武汉大学水资源工程与调度全国重点实验室湖北武汉430072 中国电建集团华东勘测设计研究院有限公司浙江杭州310010

夯沉量是反映强夯地基加固质量的关键指标,人工测量方法不仅投入高、效率低下,且施工安全无法保障。为此,基于单目摄影测量提出一种强夯夯沉量非接触测量方法,实现了强夯夯沉量的高效测算。深入分析并科学定义了适用于单目视觉监测的夯... 详细信息

夯沉量是反映强夯地基加固质量的关键指标,人工测量方法不仅投入高、效率低下,且施工安全无法保障。为此,基于单目摄影测量提出一种强夯夯沉量非接触测量方法,实现了强夯夯沉量的高效测算。深入分析并科学定义了适用于单目视觉监测的夯沉量定义;基于夯锤标识的旋转不变性,提取表征夯锤姿态的特征点几何信息,结合视觉成像基本原理,构建了测算夯锤三维姿态的数值方程,求解得到夯锤特征点的三维坐标;在施工现场对所提方法进行工程实测,并通过多余观测对解算结果进行优化尝试。试验及工程应用结果表明,本方法具有精度高、速度快、稳健性强等特点,可有效应用于强夯施工质量监测关键指标参数夯沉量的自动解算,为当前强夯夯沉量自动化监测技术的进步提供了一个新的方向和手段。

关键词：夯沉量监测单目视觉测量夯锤位姿旋转不变性

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移动式发电车低压台区不停电作业技术探析

电力设备管理 2024年第18期 232-234页

作者：尹龙深圳带电科技发展有限公司

本文以本公司0.4kV低压项目为视角,开展不停电持续性的作业分析,以移动式发电车为出发点,应对低压台区供电不间断的需求,引入了负荷转移、准同期并网等多个技术,以此防止出现断电问题,确保供电的持续性,稳步推进各项作业活动。经过实际... 详细信息

本文以本公司0.4kV低压项目为视角,开展不停电持续性的作业分析,以移动式发电车为出发点,应对低压台区供电不间断的需求,引入了负荷转移、准同期并网等多个技术,以此防止出现断电问题,确保供电的持续性,稳步推进各项作业活动。经过实际并网测试发现:不停电持续性作业技术具有操作安全、供电平稳的特点,适用于配电网运检体系。

关键词：发电车负荷转移检修

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智能研究与实训两用船高效搭载技术

中国修船 2024年第3期37卷 30-32,36页

作者：尹龙大连中远海运重工有限公司辽宁大连116113

为适应现代造船模式,实现降本增效、缩短建造周期,文章对智能研究与实训两用船搭载技术进行研究。根据该船型功能区域特点,采用“壳舾涂”一体化造船模式。通过先进工法技术和先进工装的研发与应用,提高生产效率,降低工人劳动强度,实现... 详细信息

为适应现代造船模式,实现降本增效、缩短建造周期,文章对智能研究与实训两用船搭载技术进行研究。根据该船型功能区域特点,采用“壳舾涂”一体化造船模式。通过先进工法技术和先进工装的研发与应用,提高生产效率,降低工人劳动强度,实现船舶高效建造。

关键词：智能研究与实训两用船搭载技术工法技术高效建造