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Effect of the Filling Liquid Ratio on the Thermal Performance of a Novel Thermal Diode with Wick

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Journal of Thermal Science 2024年第2期33卷 396-407页

作者： LI Zhiyong MING Tingzhen ZHANG Heyu ZHAO Sitong WANG Qinggang CAI Cunjin YIN Kui FANG Yueping WU Yongjia School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan430070China Sanya Science and Education Innovation Park Wuhan University of TechnologySanya572004China Deparment of Four Station Logistics AcademyXuzhou221000China School of Energy Construction and EnvironmentCoventry UniversityPriory StreetCoventryCV15FBUK

The application of thermal diodes,which allow heat to flow more readily in one direction than the other,is an important way to reduce energy consumption in buildings and enhance the battery heat dissipation of electric vehicles.Depending on various factors including the specific design,materials used,and operating conditions,the convective thermal diode can exhibit the best thermal rectification effect in intended applications compared to the other thermal diodes.In this study,a novel convective thermal diode with a wick was proposed based on the phase change heat transfer mechanism.This design takes advantage of both capillary forces provided by the wick and gravity to achieve enhanced unidirectional heat transfer performance for the designed convective thermal diode.The effect of the filling liquid ratio on the thermal performance of the thermal diode was experimentally investigated,which was in good agreement with the theoretical analysis.The research findings showed that with an optimal liquid filling ratio of 140%,the thermal diode with a wick can achieve a better thermal rectification ratio when subjected to a lower heating power,and the maximum thermal rectification ratio of 21.76 was experimentally achieved when the heating power of the thermal diode was 40 W.

关键词： filling liquid ratio thermal diode wick structure gravity

基于CNN–LSTM的风电场发电功率迁移预测方法

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工程科学与技术 2024年第2期56卷 91-99页

作者：唐清苇向月代佳琨李子豪孙炜刘俊勇四川大学电气工程学院四川成都610065 爱丁堡大学工程学院爱丁堡EH93FB

随着能源消耗的持续增长和全球气候问题的日趋严峻,以风能为代表的清洁能源装机容量正在稳步提升。为更好地消纳风电,需要准确的风电场发电功率预测为配套设施建设和未来规划制定提供有效依据。针对在缺少风电历史运行数据时预测精度较... 详细信息

随着能源消耗的持续增长和全球气候问题的日趋严峻,以风能为代表的清洁能源装机容量正在稳步提升。为更好地消纳风电,需要准确的风电场发电功率预测为配套设施建设和未来规划制定提供有效依据。针对在缺少风电历史运行数据时预测精度较低的问题,提出一种基于卷积神经网络–长短期记忆神经网络(CNN–LSTM)的规划阶段风电场发电功率预测模型。首先,基于参考电站历史数据提取风速–风电功率实测数据点,采用3次样条插值进行风电功率曲线建模。然后,采用K–means聚类算法,根据风速–风电功率的特性关系划分参考风电场的区域类别。综合考虑风电功率与多维气象因素的特征关系和功率的时序特性,构建CNN–LSTM预测模型,提出基于功率曲线的预测结果修正方法。最后,基于某地风电场实际数据进行算例分析,并与使用标准功率曲线和未进行修正时的预测结果进行对比分析。结果表明:基于风速–风电功率特性的风电场聚类可以实现参考风电场的优化识别;所提模型预测结果优于传统标准功率曲线预测方法,基于功率曲线的修正方法进一步提升了预测效果。基于深度学习算法的规划阶段风电场发电功率迁移预测模型综合考虑了风力发电特性和多维环境因素,其有效性得到了验证,可以为提高规划阶段风电场发电功率的预测精度提供新思路。

关键词：风电预测长短期记忆神经网络卷积神经网络功率曲线风电场规划

男性运动员睡眠障碍的神经机制探究:基于复杂网络模型

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中国体育科技 2024年第2期60卷 11-20页

作者：李秦陇车开萱 Charles JSteward 赵丽周越北京体育大学北京100084 考文垂大学英国考文垂CV15FB

目的:通过使用无目标不加权及目标加权的复杂网络模型方法,分析睡眠障碍运动员睡前神经机能状态与睡眠质量的复杂作用方式,揭示运动员发生睡眠障碍的神经机能状态特征。方法:在睡眠实验室内使用多导睡眠仪监测14名男性睡眠障碍运动员4... 详细信息

目的:通过使用无目标不加权及目标加权的复杂网络模型方法,分析睡眠障碍运动员睡前神经机能状态与睡眠质量的复杂作用方式,揭示运动员发生睡眠障碍的神经机能状态特征。方法:在睡眠实验室内使用多导睡眠仪监测14名男性睡眠障碍运动员4晚完整睡眠,并在睡前使用便携式脑电仪、超慢波涨落潮技术、Polar H10心率胸带和心境状态量表,分别测试或评估中枢机能状态、脑内神经递质水平、自主神经状态以及情绪状态。基于测试数据分别建立无目标不加权,以及以睡眠质量为目标的加权复杂网络模型。结果:1)无目标不加权的复杂网络模型中,介数中心性结果提示,慌乱、精力和愤怒情绪、α抑制%、去甲肾上腺素(NE)和多巴胺、相邻窦性R-R间期差值大于50 ms所占百分比(PNN50)、平均R-R间隔、平均心率(MHR)和睡眠总时间是此网络的关键影响节点。特征向量中心性分析结果显示,上述指标中除PNN50、NE和MHR外,抑郁、紧张和疲劳情绪与其他指标仍是网络的重要连接节点。2)在以睡眠质量为目标的加权复杂网络模型中,目标介数中心性结果发现,情绪状态在到达睡眠质量指标的最短路径中出现频率最高(48.57%),其次神经递质和睡眠指标频率相同(14.29%),而中枢神经机能状态和自主神经状态出现的频率最低(11.43%)。目标特征向量中心性结果表明,情绪状态成为影响睡眠质量最重要的影响因素,出现频率为82.86%,其次是自主神经状态出现频率为8.57%,而中枢神经机能状态、神经递质和睡眠指标出现频率相同(2.86%)。结论:运动员睡眠障碍的主要表现为总时长短,睡眠期间觉醒时间长导致睡眠效率低。复杂网络模型方法揭示了情绪(主要为消极情绪)是睡眠质量低和睡眠障碍发生的主要影响节点和关键因素,其中愤怒、慌乱情绪与脑内神经递质(5-HT和DA)、中枢疲劳程度相关,中枢疲劳程度和自主神经协调性与精力状态相关。

关键词：睡眠质量情绪状态神经系统复杂网络模型

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Towards an L^p Potential Theory for Sub-Markovian Semigroups:Kernels and Capacities

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Acta Mathematica Sinica,English Series 2006年第4期22卷 1227-1250页

作者： Niels JACOB RenéL.SCHILLING Department of Mathematics University of Wales SwanseaSingleton ParkSwansea SA 2 8 PP.United Kinadom fb 12-mathematik Philipps-Universitat MarburgD-35032 MarburgGermany

We study in fairly general measure spaces （X,μ） the （non-linear） potential theory of L^p sub-Markovian semigroups which are given by kernels having a density with respect to the underlying measure. In terms of mapping properties of the operators we provide sufficient conditions for the existence （and regularity） of such densities. We give various （dual） representations for several associated capacities and, in the corresponding abstract Bessel potential spaces, we study the role of the truncation property. Examples are discussed in the case of R^n where abstract Bessel potential spaces can be identified with concrete function spaces.

关键词： nonlinear potential theory （r,p）-capacity Bessel potential space gamma.transform sub-Markovian semigroup

Analysis and Invariant Properties of a Lattice Boltzmann Method

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Advances in Applied Mathematics and Mechanics 2010年第5期2卷 640-669页

作者： Michael Junk Zhaoxia Yang fb mathematik und Statistik Universit¨at KonstanzPostfach D19478457 KonstanzGermany

We investigate a two-relaxation-time(TRT)lattice Boltzmann algorithm with the asymptotic analysis technique.The results are used to analyze invariance properties of the method.In particular,we focus on time dependent ... 详细信息

关键词： Two-relaxation-time LBM invariance property asymptotic analysis

Asymptotic Analysis of Lattice Boltzmann Outflow Treatments

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Communications in Computational Physics 2011年第5期9卷 1117-1127页

作者： Michael Junk Zhaoxia Yang fb mathematik und Statistik Universität KonstanzPostfach D19478457 KonstanzGermany

We show the methodology and advantages of asymptotic analysis when applied to lattice Boltzmann outflow treatments.On the one hand,one can analyze outflow algorithms formulated directly in terms of the lattice Boltzmann variables,like the extrapolation method,to find the induced outflow conditions in terms of the NavierStokes variables.On the other hand,one can check the consistency and accuracy of lattice Boltzmann outflow treatments to given hydrodynamic outflow conditions like the Neumann or average pressure condition.As example how the gained insight can be used,we propose an improvement of the well known extrapolation method.

关键词： Outflow condition asymptotic analysis lattice Boltzmann method

生态农产品品牌形象对消费者信任的影响——基于消费者社交网络参与度的调节效应

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现代农业研究 2024年第2期30卷 6-13页

作者：袁晓辉汪卓然王祥文西南大学重庆400715 Coventry University London CV15fb 重庆大学建筑规划设计研究总院有限公司重庆400030

本文基于信号传递理论阐述了生态农产品品牌形象影响消费者信任的逻辑机理,并利用全国1113位有机牛奶消费者的微观调查数据,实证检验了生态农产品品牌形象对消费者信任的影响效应及其传导机制。结果表明:(1)品牌作为一种能够降低消费者... 详细信息

本文基于信号传递理论阐述了生态农产品品牌形象影响消费者信任的逻辑机理,并利用全国1113位有机牛奶消费者的微观调查数据,实证检验了生态农产品品牌形象对消费者信任的影响效应及其传导机制。结果表明:(1)品牌作为一种能够降低消费者选择成本的排他性品类符号,具有重要的信息传递功能,对于解决生态农产品市场的信息不对称问题有积极意义,但不同品牌的影响力和号召力不同,其原因在于品牌形象存在差异,品牌形象越好,消费者对产品信任度越高。(2)在品牌形象对消费者信任的影响关系中,消费者社交网络参与度发挥着一定程度的正向调节作用,品牌形象对社交网络参与度较高的消费者产品信任影响较为强烈。(3)品牌形象对消费者信任的影响存在一定的异质性,对于社会信任水平较低和生态认知水平较高的消费者而言,品牌形象对其产品信任的影响较为显著。

关键词：生态农产品品牌形象消费者信任社交网络参与度

Consensus Clustering for Bi-objective Power Network Partition

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CSEE Journal of Power and Energy Systems 2022年第4期8卷 973-982页

作者： Yi Wang Luzian Lebovitz Kedi Zheng Yao Zhou the Power Systems Laboratory ETH Zurich8092 ZurichSwitzerland Department of Elctrical Engineering Tsinghua UniversityBeijing 100084China School of Engineering the University of EdinburghEH93FBEdinburghUK

Partitioning a complex power network into a number of sub-zones can help realize a divide-and-conquer’management structure for the whole system,such as voltage and reactive power control,coherency identification,power system restoration,etc.Extensive partitioning methods have been proposed by defining various distances,applying different clustering methods,or formulating varying optimization models for one specific objective.However,a power network partition may serve two or more objectives,where a trade-off among these objectives is required.This paper proposes a novel weighted consensus clustering-based approach for bi-objective power network partition.By varying the weights of different partitions for different objectives,Pareto improvement can be explored based on the node-based and subset-based consensus clustering methods.Case studies on the IEEE 300-bus test system are conducted to verify the effectiveness and superiority of our proposed method.

关键词： Consensus clustering network partition bi-objective partition machine learning

The Plastid-Localized NAD-Dependent Malate Dehydrogenase Is Crucial for Energy Homeostasis in Developing Arabidopsis thaliana Seeds

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Molecular Plant 2014年第1期7卷 170-186页

作者： Jennifer Selinski Nicolas Konig Benedikt Wellmeyer Guy T. Hanke Vera Linke H. Ekkehard Neuhaus Renate Scheibe Department of Plant Physiology FB 5 University of Osnabrueck D-49069 Osnabrueck Germany Department of Plant Physiology FB Biology TU Kaiserslautern D-67663 Kaiserslautern Germany

In the absence of photosynthesis, ATP is imported into chloroplasts and non-green plastids by ATP/ADP transporters or formed during glycolysis, the latter requiring continuous regeneration of NAD＋, supplied by the plastidial isoform of NAD-MDH. During screening for T-DNA insertion mutants in the plNAD-MDH gene of Arabidopsis, only heterozygous plants could be isolated and homozygous knockout mutants grew only after complementation. These heterozygous plants show higher transcript levels of an alternative NAD＋-regenerating enzyme, NADH-GOGAT, and, remarkably, improved growth when ammonium is the sole N-source. In situ hybridization and GUS-histochemical stain- ing revealed that plNAD-MDH was particularly abundant in male and female gametophytes. Knockout plNAD-MDH pollen exhibit impaired tube growth in vitro, which can be overcome by adding the substrates of NADH-GOGAT. In vivo, knockout pollen is able to fertilize the egg cell. Young siliques of selfed heterozygous plants contain both green and white seeds corresponding to wild-type/heterozygous （green） and homozygous knockout mutants （white） in a （1：2）：1 ratio. Embryos of the homozygous knockout seeds only reached the globular stage, did not green, and developed to tiny wrinkled seeds. Complementation with the gene under the native promoter rescued this defect, and all seeds developed as wild-type. This suggests that a blocked major physiological process in plNAD-MDH mutants stops both embryo and endosperm development, thus avoiding assimilate investment in compromised offspring.

关键词： malate valve plastidial glycolysis ammonium assimilation NADH-GOGAT redox-balance embryo lethality.