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Journal of Thermal Science 2024年第4期33卷 1577-1589页

作者： CHEN Chengdai wang changhong ZHENG Zijun School of Materials and Energy Guangdong University of TechnologyGuangzhou510006China

The effective cathode flow field design can realize the internal water balance and higher current density output of proton exchange membrane fuel cells(PEMFC).Therefore,a segmented water management flow field is proposed in this study,i.e.a half separated-half coupled cathode(HSHC)flow field which has two inlets but just one outlet.A 3D numerical PEMFC model is applied to study the effect of the HSHC flow field on PEMFC performance and its operating strategy in terms of operating *** study results are shown as follows:Compared with the two conventional cathode flow fields,the HSHC flow field improves the water balance along the channel and increases the current density by 17.1%at a cathode stoichiometry of *** is because the HSHC flow field can overcome the water loss at channels upstream and the water accumulation at channels *** draw water phenomenon(DWP)in the HSHC flow field is observed,which is mainly affected by the water vapor pressure of *** on the DWP,cooling channel inlet flow rates can be used to adjust water balance,but severe water loss should be *** addition,the inlet temperature control in HSHC flow field should be that cell temperature>cathode channel inlet temperature>cooling channel inlet temperature>ambient temperatures for better water balance.

关键词： proton exchange membrane fuel cells channel design segmented water management water balance operating strategy

Ensemble successor representations for task generalization in offline-to-online reinforcement learning

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Science China(Information Sciences) 2024年第7期67卷 240-255页

作者： changhong wang Xudong YU Chenjia BAI Qiaosheng ZHANG Zhen wang Space Control and Inertial Technology Research Center Harbin Institute of Technology Shanghai Artificial Intelligence Laboratory Shenzhen Research Institute of Northwestern Polytechnical University School of Cybersecurity Northwestern Polytechnical University

In reinforcement learning(RL), training a policy from scratch with online experiences can be inefficient because of the difficulties in exploration. Recently, offline RL provides a promising solution by giving an initialized offline policy, which can be refined through online interactions. However, existing approaches primarily perform offline and online learning in the same task, without considering the task generalization problem in offline-to-online adaptation. In real-world applications, it is common that we only have an offline dataset from a specific task while aiming for fast online-adaptation for several tasks. To address this problem, our work builds upon the investigation of successor representations for task generalization in online RL and extends the framework to incorporate offline-to-online learning. We demonstrate that the conventional paradigm using successor features cannot effectively utilize offline data and improve the performance for the new task by online fine-tuning. To mitigate this, we introduce a novel methodology that leverages offline data to acquire an ensemble of successor representations and subsequently constructs ensemble Q functions. This approach enables robust representation learning from datasets with different coverage and facilitates fast adaption of Q functions towards new tasks during the online fine-tuning *** empirical evaluations provide compelling evidence showcasing the superior performance of our method in generalizing to diverse or even unseen tasks.

关键词： offline reinforcement learning online fine-tuning task generalization successor representations ensembles

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《周易》经、传与《墨子》关系发微——兼论战国时期的儒、墨关系

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孔子研究 2024年第1期 108-116,159页

作者：王长红齐鲁师范学院文学院济南250200

《周易》在古代被称为群经之首、大道之源,其思维范式和思想内容不但是儒家思想体系产生、发展的形上根据,而且与部分诸子学说的思想架构也有着千丝万缕的联系,在先秦思想史和文化史上占有重要位置。比较《系辞传》和《墨子·节用篇》... 详细信息

《周易》在古代被称为群经之首、大道之源,其思维范式和思想内容不但是儒家思想体系产生、发展的形上根据,而且与部分诸子学说的思想架构也有着千丝万缕的联系,在先秦思想史和文化史上占有重要位置。比较《系辞传》和《墨子·节用篇》语言文字、逻辑理路的异同,可见《易传》《墨子》间的内在关联;梳理《周易》古经的思想元素与《墨子》思想内容的内在联系,可见《周易》古经在墨家思想体系形成中的作用,进而管窥战国时期的儒、墨关系。

关键词：《周易》经、传《墨子》篇章形成思想体系形上根据

Active metasurface via magnetic control for tri-channel polarization multiplexing holography

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Chinese Optics Letters 2024年第4期22卷 112-118页

作者：毕钰黄玲玲李拓王长红邹晓峰周朗康果果 Shandong Inspur Artificial Intelligence Research Institute Company Limited Jinan 250013China MIIT Key Laboratory of Photonics Information Technology School of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China

Active metasurfaces have recently attracted more attention since they can make the light manipulation be versatile and real-time. Metasurfaces-based holography possesses the advantages of high spatial resolution and enormous information capacity for applications in optical displays and encryption. In this work, a tunable polarization multiplexing holographic metasurface controlled by an external magnetic field is proposed. The elaborately designed nanoantennas are arranged on the magneto-optical intermediate layer, which is placed on the metallic reflecting layer. Since the non-diagonal elements of the dielectric tensor of the magneto-optical material become non-zero values once the external magnetic field is applied,the differential absorption for the left and right circularly polarized light can be generated. Meanwhile, the amplitude and phase can be flexibly modulated by changing the sizes of the nanoantennas. Based on this, the dynamic multichannel holographic display of metasurface in the linear and circular polarization channels is realized via magnetic control, and it can provide enhanced security for optical information storage. This work paves the way for the realization of magnetically controllable phase modulation, which is promising in dynamic wavefront control and optical information encryption.

关键词： active metasurface magneto-optical effect polarization multiplexing holography dynamic holographic display

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波束开角对多普勒测频结果的影响

应用声学 2024年第1期43卷 40-46页

作者：陈茁王长红邓锴中国科学院声学研究所北京100190 中国科学院大学北京100049 北京市海洋声学装备工程技术研究中心北京100190

具有不同波束开角的声学多普勒测速设备未标定的测速结果存在偏差。基于水底椭圆散射模型研究了波束开角对声学多普勒测速结果的影响,对提高声学测速性能具有实际意义。水底椭圆散射模型下,足印上不同方位传播损失和散射强度存在差异,... 详细信息

具有不同波束开角的声学多普勒测速设备未标定的测速结果存在偏差。基于水底椭圆散射模型研究了波束开角对声学多普勒测速结果的影响,对提高声学测速性能具有实际意义。水底椭圆散射模型下,足印上不同方位传播损失和散射强度存在差异,导致频谱不对称,测频结果偏小。利用不对称系数量化频谱不对称程度,若波束开角增大,方位不对称系数随之增大,测频偏差增大,推导了波束开角导致的测频偏差解析式。分析仿真和外场试验数据测频结果可知,不同多普勒频移下测频偏差和理论计算值相符,不同波束开角下实际测频偏差与理论公式计算的测频偏差均随波束开角增大而增大。

关键词：宽带多普勒测速波束开角误差分析

半乳糖凝集素3及血小板与淋巴细胞比值与75岁以上急性心肌梗死患者术后心室重构的关系

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中华老年心脑血管病杂志 2024年第5期26卷 504-507页

作者：张新贵王长虹王进南阳市第一人民医院全科医学科 473000

目的探讨外周血半乳糖凝集素3(Gal-3)、血小板与淋巴细胞比值(PLR)水平变化及其与75岁以上急性心肌梗死(AMI)患者经皮冠状动脉介入治疗(PCI)术后发生心室重构的关系。方法选择2021年3月至2023年9月在南阳市第一人民医院择期行PCI术的75... 详细信息

目的探讨外周血半乳糖凝集素3(Gal-3)、血小板与淋巴细胞比值(PLR)水平变化及其与75岁以上急性心肌梗死(AMI)患者经皮冠状动脉介入治疗(PCI)术后发生心室重构的关系。方法选择2021年3月至2023年9月在南阳市第一人民医院择期行PCI术的75岁以上老年AMI患者86例,根据PCI术后是否发生心室重构将患者分为心室重构组39例和非心室重构组47例。于PCI术前、术后3d、术后5d检测Gal-3、PLR水平,比较2组外周血Gal-3、PLR水平,用多因素logistic回归分析外周血Gal-3、PLR水平与老年AMI患者PCI术后发生心室重构的关系,用ROC曲线分析外周血Gal-3、PLR水平对老年AMI患者PCI术后发生心室重构的预测价值。结果2组患者术后3d、术后5d外周血Gal-3、PLR水平均较术前降低,且术后5d外周血Gal-3、PLR水平低于术后3d(P<0.05);心室重构组术前、术后3d、术后5d的外周血Gal-3、PLR水平均高于非心室重构组(P<0.05,P<0.01)。多因素logistic回归分析显示,术前Gal-3(OR=1.986,95%CI:1.017~2.875,P=0.007)、术前PLR(OR=1.774,95%CI:1.132~2.428,P=0.014)均是AMI患者PCI术后发生心室重构的危险因素。ROC曲线显示,术前外周血Gal-3和PLR联合预测AMI患者PCI术后发生心室重构的曲线下面积为0.882(95%CI:0.824~0.941),优于二者单独检测(P<0.05)。结论AMI患者PCI术后外周血Gal-3、PLR水平较术前降低,术前外周血Gal-3、PLR均是PCI术后发生心室重构的危险因素,联合检测对AMI患者PCI术后发生心室重构有较高预测价值。

关键词：心肌梗死心室重构半乳糖凝集素3 血小板与淋巴细胞比值

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部分排水条件下静力触探试验力学机理研究

岩土工程学报 2024年第3期46卷 519-528页

作者：王长虹方恬吴昭欣王昆汤道飞上海大学力学与工程科学学院土木工程系上海200444

在自然状态下,大部分土体的约束条件介于完全排水和不排水两者之间。在孔压静力触探试验(piezocone penetrationtest,CPTU)的贯入过程中,受探头尺寸、贯入速度和岩土材料等因素的影响,将发生部分排水现象。为研究排水条件对CPTU试验数... 详细信息

在自然状态下,大部分土体的约束条件介于完全排水和不排水两者之间。在孔压静力触探试验(piezocone penetrationtest,CPTU)的贯入过程中,受探头尺寸、贯入速度和岩土材料等因素的影响,将发生部分排水现象。为研究排水条件对CPTU试验数据的影响,开展三轴压缩试验。引入应变增量比,建立考虑渐近状态的修正剑桥(Modified Cam-Clay,MCC)模型。推导考虑渐近状态MCC模型的柱孔扩张理论,提出CPTU测试数据的力学模型。通过数值模拟和模型槽试验,研究归一化贯入速度与排水系数的规律。结合CPTU数据的力学模型,获得应变增量比与排水系数的数理关系。最后以上海市苏州河地区深层排水调蓄管道系统工程的测试数据为背景,验证力学模型的正确性。结果表明:在部分排水条件下,利用考虑渐近状态的MCC模型,能够描述土体的应力-应变关系,合理解释CPTU贯入的力学机理。

关键词：孔压静力触探部分排水渐近状态柱孔扩张理论应变增量比

Calibration method of quartz accelerometer on dynamic centrifuge

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Chinese Journal of Aeronautics 2022年第6期35卷 262-272页

作者： Yingbo SUN Shunqing REN changhong wang School of Astronautics Harbin Institute of TechnologyHarbin 150001China

This paper proposes a novel method for calibrating error coefficients of the quartz accelerometer faster on the dynamic centrifuge,which can generate a continuous dynamic acceleration ***,working principle and structure of the dynamic centrifuge are analyzed,the error sources and the uncertainty of the dynamic centrifuge are expounded,and relevant coordinate systems are ***,according to the characteristics of the input specific forces and the propagating methods of the error sources,the accurate input specific forces acted on the input reference axes of accelerometer are *** on the calibration error model of the accelerometer,the corresponding dynamic calibration method is ***,the second-order and high-order coefficients of the acceleration error model are calibrated,and the calibration precision of the coefficients is *** with traditional calibration methods,the method proposed in this paper not only greatly enhances the calibration efficiency by reducing the installing positions of the accelerometer,but also separates the centrifuge errors from the outputs of the accelerometer,which improves the accuracy and efficiency of the calibration method simultaneously.

关键词： Accelerometer Calibration Dynamic centrifuge Dynamic excitation stimulus Error model Homogeneous transformation

上扬子地区新地1井五峰组—龙马溪组下段高分辨化学层序地层学与页岩气关系分析

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中国地质 2024年第4期51卷 1355-1367页

作者：王茜黄永建张治锋王长红李祥刘伟中国地质科学院北京100037 中国地质大学(北京)地球科学与资源学院北京100083 中国地质调查局成都地质调查中心四川成都610082

【研究目的】本文旨在综合地球化学、高分辨层序地层学理论和方法,探索厚层页岩地层划分对比的化学层序地层新方法,建立上扬子地区新地1井五峰组—龙马溪组下段高精度化学层序地层格架,为研究区页岩气勘探提供科学依据。【研究方法】本... 详细信息

【研究目的】本文旨在综合地球化学、高分辨层序地层学理论和方法,探索厚层页岩地层划分对比的化学层序地层新方法,建立上扬子地区新地1井五峰组—龙马溪组下段高精度化学层序地层格架,为研究区页岩气勘探提供科学依据。【研究方法】本研究利用上扬子地区新地1井的岩心、测井及样品分析测试资料,优选出陆源输入强度相关元素组合、自生沉淀强度相关元素组合、有机质吸附及还原强度相关元素组合作为指标体系,进而划分四级化学层序地层。【研究结果】新地1井五峰组划分为LCW层序,龙马溪组下段自下而上细分为MCL1-1、MCL1-2、MCL1-3、MCL1-4四级层序。陆源输入强度相关元素组合总量在层序界面附近相对较高,而最大海泛面附近相对较低;自生沉淀强度及有机质吸附及还原强度相关元素组合总量在层序界面附近相对较低,而在最大海泛面附近相对较高。【结论】不同地化指标体系代表了不同的成因意义,陆源碎屑输入强度和自生沉淀强度越小、有机质吸附及还原强度越大的沉积环境有利于页岩中有机质富集,其旋回性变化对区域海平面变化有相应响应,具有区域一致性,是区域地层对比的重要依据和有力手段。

关键词：上扬子地区新地1井五峰组龙马溪组化学层序地层学地质调查工程

Surface-mediated iron on porous cobalt oxide with high energy state for efficient water oxidation electrocatalysis

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Green Energy & Environment 2022年第4期7卷 662-671页

作者： Jingsha Li Tao Hu changhong wang Chunxian Guo Institute of Materials Science and Devices Suzhou University of Science and TechnologySuzhou215011China

Surface engineering of active materials to generate desired energy state is critical to fabricate high-performance heterogeneous ***, its realization in a controllable level remains challenging. Using oxygen evolution reaction(OER) as a model reaction, we report a surface-mediated Fe deposition strategy to electronically tailor surface energy states of porous Co_(3)O_(4)(Fe-pCo_(3)O_(4)) for enhanced activity towards OER. The Fe-pCo_(3)O_(4) exhibits a low overpotential of 280 mV to reach an OER current density of 100 mA cm^(-2), and a fast-kinetic behavior with a low Tafel slop of 58.2 mV dec^(-1), outperforming Co_(3)O_(4)-based OER catalysts recently reported and also the noble IrO_(2). The engineered material retains 100% of its original activity after operating at an overpotential of 350 m V for 100 h. A combination of theoretical calculations and experimental results finds out that the surface doped Fe promotes a high energy state and desired coordination environment in the near surface region, which enables optimized OER intermediates binding and favorably changes the rate-determining step.

关键词： Surficial Fe doping Cobalt oxides High energy state Water oxidation Oxygen evolution reactions