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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

Surface Coating Enabling Sulfide Solid Electrolytes with Excellent Air Stability and Lithium Compatibility

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Energy & Environmental Materials 2024年第6期7卷 41-49页

作者： Min Luo changhong wang Yi Duan Xuyang Zhao Jiantao wang Xueliang Sun National Power Battery Innovation Center GRINM Group Corporation LimitedBeijing 100088China China Automotive Battery Research Institute Co. Ltd.Beijing 100088China General Research Institute for Nonferrous MetalsBeijing 100088China Eastern Institute for Advanced Study Eastern Institute of TechnologyNingbo 315200China

All-solid-state lithium metal batteries(ASSLMBs)featuring sulfide solid electrolytes(SEs)are recognized as the most promising next-generation energy storage technology because of their exceptional safety and much-improved energy ***,lithium dendrite growth in sulfide SEs and their poor air stability have posed significant obstacles to the advancement of sulfide-based ***,a thin layer(approximately 5 nm)of g-C_(3)N_(4)is coated on the surface of a sulfide SE(Li_(6)PS_(5)Cl),which not only lowers the electronic conductivity of Li_(6)PS_(5)Cl but also achieves remarkable interface stability by facilitating the in situ formation of ion-conductive Li3N at the Li/Li_(6)PS_(5)Cl ***,the g-C_(3)N_(4)coating on the surface can substantially reduce the formation of H_(2)S when Li_(6)PS_(5)Cl is exposed to humid *** a result,Li-Li symmetrical cells using g-C_(3)N_(4)-coated Li_(6)PS_(5)Cl stably cycle for 1000 h with a current density of 0.2 mA cm^(-2).ASSLMBs paired with LiNbO_(3)-coated LiNi_(0.6)Mn_(0.2)Co_(0.2)O_(2)exhibit a capacity of 132.8 mAh g^(-1)at 0.1 C and a high-capacity retention of 99.1%after 200 ***,g-C_(3)N_(4)-coated Li_(6)PS_(5)Cl effectively mitigates the self-discharge behavior observed in *** surface-coating approach for sulfide solid electrolytes opens the door to the practical implementation of sulfide-based ASSLMBs.

关键词： anode interface g-C_(3)N_(4)coating Li_(6)PS_(5)Cl lithium dendrite inhibition solidstate lithium metal batteries

Ocean wave directional spectrum estimation using spatio-temporal array of acoustic ranging and current measurement

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Chinese Journal of Acoustics 2024年第3期43卷 311-331页

作者： RAO Liang DENG Kai ZHANG Zhaowei wang changhong Institute of Acoustics Chinese Academy of SciencesBeijing100190 University of Chinese Academy of Sciences Beijing100049 Beijing Engineering Technology Research Center of Ocean Acoustic Equipment Beijing100190

An approach to estimate ocean wave directional spectrum using spatio-temporal array of acoustic ranging and current measurement is proposed,and the 5-beam acoustic Doppler current profiler(ADCP)constructs a spatio-temporal array of acoustic ocean surface elevation tracking and acoustic Doppler current velocity measuring for directional wave *** on the linear wave theory and the space-time equivalence principle,the time-space transfer function applicable to the spatio-temporal array is proposed,and then the time delay term is compensated in the calculation of the covariance *** method can reduce the error of the directional spectrum *** results show that for the low signal-to-noise ratio from 0 dB to 5 dB,compared with the 4-beam synchronous array method,this method has a smaller root-mean-square error of the peak estimation of the directional *** field test shows that,compared with the 4-beam synchronous array method,the 5-beam spatio-temporal array method improves the kurtosis index of the directional spectrum from 2.31 to 2.80,and the correlation coefficient between the peak wave direction results of the ADCP and the buoy is increased from 0.80 to 0.83 in mild wave ***,the spatio-temporal array method can increase the degree of freedom of wave measurement,reduce the minimum aperture of the array,and increase the upper cut-off frequency of the estimable directional spectrum.

关键词： spectrum ocean directional

《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

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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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空时联合的声学测高测流阵列海浪方向谱估计

声学学报 2024年第5期49卷 1019-1029页

作者：饶亮邓锴张兆伟王长红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

提出了一种空时联合的声学测高测流阵列海浪方向谱估计方法,使用五波束声学多普勒流速剖面仪(ADCP)构建声学海表跟踪测高、声学多普勒测流速分时采样的空间阵列进行海浪方向谱估计。依据线性波浪理论和时空等效性原理,提出适用于空时阵... 详细信息

提出了一种空时联合的声学测高测流阵列海浪方向谱估计方法,使用五波束声学多普勒流速剖面仪(ADCP)构建声学海表跟踪测高、声学多普勒测流速分时采样的空间阵列进行海浪方向谱估计。依据线性波浪理论和时空等效性原理,提出适用于空时阵列的时间空间传递函数,在协方差矩阵中补偿时间延迟项,减小方向谱估计误差。仿真结果表明:在0 dB至5 dB低信噪比时,相比于同步四波束阵列法,此方法的方向谱谱峰估计值均方根误差更小。海试结果表明:五波束空时联合阵列法相比于同步四波束阵列法,估得方向谱峰度从2.31提升至2.80,小波浪组次谱峰波向结果与浮标结果的相关系数从0.80提升至0.83。同时,空时联合法能提升测波自由度、减小阵列最小孔径,提高了可估方向谱的上限截止频率。

关键词：波浪方向谱声学多普勒测速声学测距空时阵列方向谱估计

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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