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Numerical multi-physical optimization of operating condition and current collecting setup for large-area solid oxide fuel cells

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Frontiers in Energy 2024年第3期18卷 356-368页

作者： Chengrong yu Zehua PAN Hongying ZHANG Bin CheN Wanbing GUAN Bin MIAO Siew Hwa CHAN Zheng ZHONG Yexin ZHOU School of Science Harbin Institute of TechnologyShenzhen 518055China Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green EnergyShenzhen UniversityShenzhen 518060China Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology of Zhejiang Province Ningbo Institute of Materials Technology and Engineering of the Chinese Academy of SciencesNingbo 315201China Energy Research Institute at NTU(ERIAN) Nanyang Technological UniversitySingapore 639798Singapore

Due to the depletion of traditional fossil fuels and the aggravation of related environmental problems,hydrogen energy is gaining more attention all over the *** oxide fuel cell(SOFC)is a promising power generation technology operating on hydrogen with a high *** further boost the power output of a single cell and thus a single stack,increasing the cell area is an effective ***,it was recently found that further increasing the effective area of an SOFC single cell with a flat-tubular structure and symmetric double-sided cathodes would result in a lower areal *** this work,a multi-physical model is built to study the effect of the effective area on the cell *** distribution of different physical fields is systematically *** of the cell performance is also pursued by systematically tuning the cell operating condition and the current collection *** improvement of 42%is revealed by modifying the inlet gas flow rates and by enhancing the current *** the future,optimization of cell geometry will be performed to improve the homogeneity of different physical fields and thus to improve the stability of the cell.

关键词： solid oxide fuel cell(SOFC) large effective area flow rate discharge performance current collection

基于事件触发自适应时域MPC的船舶靠泊方法

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控制与决策 2024年第1期39卷 336-344页

作者：苑守正刘志林郑林熇孙雨鑫哈尔滨工程大学智能科学与工程学院哈尔滨150001 哈尔滨工程大学船海装备智能化技术与应用教育部重点实验室哈尔滨150001 中国船舶集团有限公司第七〇三研究所哈尔滨150078

船舶在自动靠泊的过程中会受到风、浪、流和岸壁效应等多种因素的干扰.鉴于此,针对全驱动船舶在复杂海洋条件下的自动靠泊问题,基于事件触发机制和模型预测控制,设计一种船舶自动靠泊控制器,以解决全驱动船舶在模型不确定性、执行器饱... 详细信息

船舶在自动靠泊的过程中会受到风、浪、流和岸壁效应等多种因素的干扰.鉴于此,针对全驱动船舶在复杂海洋条件下的自动靠泊问题,基于事件触发机制和模型预测控制,设计一种船舶自动靠泊控制器,以解决全驱动船舶在模型不确定性、执行器饱和、未知环境扰动以及岸壁效应等因素影响下的船舶自动靠泊问题.首先将船舶的三自由度模型进行线性化和离散化处理,并根据全驱动船舶的特性采用先泊位外镇定再平行靠拢的靠泊方式;然后为了提高求解速度,提出一种基于事件触发的自适应时域模型预测控制方案并进行稳定性分析;最后对一艘全驱动船舶进行仿真实验,将所提出的控制方案与其他已知方法进行对比.实验结果表明,所提出控制方案不仅能明显降低运算时间,而且具有更好的控制效果.

关键词：船舶控制航迹规划自动靠泊模型预测控制事件触发控制

基于高通量磁控共溅射技术的非晶合金纳米摩擦学性能研究

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机械工程学报 2024年第15期60卷 185-193页

作者：曾鑫赖建平王驰袁小虎李丁骏余家欣西南科技大学制造过程测试技术教育部重点实验室绵阳621010 长寿命高温材料国家重点实验室德阳618000 东方电气集团东方汽轮机有限公司德阳618000

采用高通量磁控共溅射技术,制备了含不同成分的Pd-W-Si非晶合金库。采用纳米压痕、纳米划痕实验,探究了压入硬度(H)和弹性模量(E)对该非晶合金体系纳米摩擦学性能的影响。研究发现:(1)随着压入硬度和弹性模量的增大,划入深度(hs)整体呈... 详细信息

采用高通量磁控共溅射技术,制备了含不同成分的Pd-W-Si非晶合金库。采用纳米压痕、纳米划痕实验,探究了压入硬度(H)和弹性模量(E)对该非晶合金体系纳米摩擦学性能的影响。研究发现:(1)随着压入硬度和弹性模量的增大,划入深度(hs)整体呈相似的减小趋势,但相比于硬度,该趋势与弹性模量的关联性更强,即弹性模量更能反映非晶合金的抗划性能。这是因为剪切转变区(Shear transformation zone,STZ)体积与硬度、弹性模量均呈负相关,但STZ体积随弹性模量的变化具有比硬度更弱的波动性。弹性模量较大的非晶合金内部STZ体积越小,非晶结构中的变形单元越不容易被激活,在同载荷下的划入深度越浅,抗划性能越好;(2)弹性回复率(η)与硬度的关联性较弱,但与H/E的关联性较强,表现为弹性回复率随H/E的增大而增加。这是因为H/E值越大的非晶合金弹性吸收的能量越多,更容易发生弹性回复;此外,非晶合金的pile-up高度随着H/E值的增加而减小的现象,也在一定程度上促进了剪切带的自由滑动,从而促进材料弹性回复。这两方面因素综合致使高H/E值的非晶合金具有更高的弹性回复率和更好的耐磨性。

关键词：高通量非晶合金纳米摩擦学硬度弹性模量

A Case of Diabetic Nephropathy with Refractory Gastroparesis and Review of the Literature

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Yangtze Medicine 2024年第2期8卷 48-55页

作者： Beibei he Ruijie Wang Xiaoli Gong Department of Nephrology Heji Hospital Changzhi Medical College Changzhi China

Background: Gastroparesis is one of the complications of diabetes mellitus, and long-term gastroparesis seriously affects patients quality of life. Most of the patients can be relieved after lifestyle improvement and medication, but refractory gastroparesis is difficult to relieve, and is still a challenge in clinical treatment. Aim: To report a case of a patient with diabetic nephropathy combined with refractory gastroparesis, and to analyse the mechanism, diagnosis, severity grading, treatment of refractory gastroparesis in conjunction with a review of the literature, and to investigate the causes of recurrent nausea and vomiting in diabetic nephropathy patients with refractory diabetic gastroparesis and the possible effective treatment options. Case Presentation: The patient was hospitalised for recurrent nausea and vomiting and diagnosed with diabetic nephropathy and gastroparesis. Symptoms recurred after medication and peritoneal dialysis, and the patients symptoms were relieved after multifaceted interventions. Conclusion: Diabetic nephropathy and refractory gastroparesis can both manifest as digestive tract symptoms, and in the face of this complex disease, it is necessary to analyse the various etiological factors and take comprehensive treatment measures.

关键词： Diabetic Nephropathy Refractory Gastroparesis Nausea Vomiting

Design and experimental investigation of potential low-thermalconductivity high-entropy rare-earth zirconates

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Journal of Advanced Ceramics 2024年第8期13卷 1132-1142页

作者： Lu Liu Hongying Dong Peng Zhang Shaokun Wang Haolei Qil Mengyu Ding Zhefeng Li yu Bai Wen Ma School of Chemical Engineering Inner Mongolia University of TechnologyHohhot 010051China Inner Mongolia Key Laboratory of Thin Film and Coatings School of Materials Science and EngineeringInner Mongolia University of TechnologyHohhot 010051China

Developing new high-entropy rare-earth zirconate(he-RE_(2)Zr_(2)O_(7))ceramics with low thermal conductivity is essential for thermal barrier coating *** this work,the average atomic spacings,interatomic forces,and average atomic masses of 16 rare-earth elements occupying the A site of the cubic A_(2)B_(2)O_(7) crystal structure were calculated by density functional *** three physical qualities,as vectors,characterize the corresponding rare-earth *** distance between two vectors quantitatively describes the difference between two rare-earth *** greater differences between two rare-earth elements,the disorder degree of he-RE_(2)Zr_(2)O_(7)is greater,and therefore,the thermal conductivity is *** to the theoretical calculations,the thermal conductivity of the ceramics gradually increases in the order of(SC_(0.2)Y_(0.2)La_(0.2)Ho_(0.2)Yb_(0.2))_(2)Zr_(2)0_(7),(SC_(0.2)Ce_(0.2)Nd_(0.2)Eu_(0.2)Gd_(0.2))_(2)Zr_(2)0_(7),(SC_(0.2)Y_(0.2)Tm_(0.2)Yb_(0.2)Lu_(0.2))_(2)Zr_(2)0_(7),and(Sc_(0.2)Er_(0.2)Tm_(0.2)Yb_(0.2)Lu_(0.2))_(2)Zr_(2)O_(7).Using the solution precursor plasma spray method and pressureless sintering method,four types of he-RE2Zr2Oz powder and bulk samples were *** samples all showed a single defective fluorite structure with a uniform distribution of the elements and a stable phase *** thermal conductivities of the sintered he-RE_(2)Zr_(2)0_(7) bulk samples ranged from 1.30 to 1.45 Wm^(-1).K^(-1) at 1400℃,and their differences were consistent with the theoretical calculation *** the ceramics,(Sc_(0.2)Y_(0.2)La_(0.2)Ho_(0.2)Yb_(0.2))_(2)Zr_(2)O_(7) had the lowest thermal conductivity(1.30 W·m^(-1)·K^(-1),1400℃),highest thermal expansion coefficient(10.19×10^(-6) K^(-1),200-1400℃),highest fracture toughness(1.69±0.28 MPa·m^(1/2)),and smallest brttleness index(3.03μm^(1/2)).Therefore,(Sc_(0.2)Y_(0.2)La_(0.2)Ho_(0.2)Yb_(0.2))_(2)Zr_(2)0_(7)is considered to be an ideal candidate material for

关键词： high-entropy ceramics rare-earth zirconate(he-RE_(2)Zr_(2)O_(7)) composition design thermal conductivity thermal barriercoatings(TBCs)

Microfacies and diagenetic alteration in a semi-deep to deep lacustrine shale: The Yanchang Formation in the Ordos Basin, china

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Petroleum Science 2024年第3期21卷 1524-1538页

作者： Bin Bai Jing-yue Hao Ling Fu yu-Xi Liu Jian-Peng Wang Lan Wang Kevin GTaylor Lin Ma Petrochina Research Institute of Petroleum Exploration and Development Beijing100083China Department of Earth and Environmental Sciences University of ManchesterM139PLUK College of Earth Sciences Jilin UniversityChangchun130061jilinChina Department of Chemical Engineering University of ManchesterM139PLUK

The mineralogical development and diagenetic sequence of lacustrine shales in the Chang 7 Member of the Yanchang Formation in the Ordos Basin are detailed studied.A model of their depositional system and a diagenetic diagram are proposed in this *** detailed petrographic,mineralogical,and elemental analyses,four distinct shale types are identified:argillaceous shale,siliceous shale,calcareous shale,and carbonate,clay,and silt-bearing *** main diagenetic process in argillaceous shale is the transformation of illite to smectite,negatively impacting shale *** shale undergoes carbonate cementation and quartz dissolution,contributing to increased porosity,particularly in *** shale experiences diagenesis characterised by carbonate formation and dissolution,with a prevalence of *** carbonate,clay,and silt-bearing shale,the dissolution of K-feldspar contributes to illitization of *** shale,characterised by more clay minerals and lower mesopore volume,is identified as a potential hydrocarbon *** shale,with the highest pore volume and abundant inter-mineral pores,emerges as a promising shale oil *** findings contribute to a comprehensive understanding of shale properties,aiding in the prediction of shale oil exploration potential in the studied area.

关键词： Ordos Basin Yanchang Formation Chang 7 Member Diagenesis Microfacies

Hardware-oriented algorithms for softmax and layer normalization of large language models

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Science china(Information Sciences) 2024年第10期67卷 85-99页

作者： Wenjie LI Dongxu Lyu Gang WANG Aokun HU Ningyi XU Guanghui he School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University Department of Micro/Nano Electronics Shanghai Jiao Tong University MoE Key Laboratory of Artificial Intelligence Shanghai Jiao Tong University

While large language models(LLMs) have sparked a new revolution in the field of natural language processing(NLP), their hardware accelerators have garnered tremendous attention. However, softmax and layer normalization which are the most common non-linear operations in LLMs are frequently *** paper presents hardware-oriented algorithms for both softmax and layer normalization of LLMs. We propose an approximate approach to implementing division in softmax and extend it for simultaneously computing square root and performing division in layer normalization. It replaces the original computation by multiplication and shifting. For softmax, we further approximate the exponential function by truncating its exponent and then reuse the involved subtraction. For layer normalization, we additionally simplify the computation of denominator by directly removing the term regarding the square of the mean. Furthermore,hardware architectures are developed for the proposed algorithms of softmax and layer normalization. They can work as plug-and-play units for LLM accelerators, requiring no fine-tuning and introducing negligible performance loss. Compared with the state-of-the-art designs, the proposed softmax architecture can save up to 23.45% area cost and 17.39% power consumption, while the proposed layer normalization architecture can save up to 32.70% area cost and 14.29% power consumption.

关键词： large language model softmax layer normalization hardware architecture Transformer

Unidirectional movement behavior of underwater bubbles on the wettability gradient mesh via asymmetrical bounce

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Science china Chemistry 2024年第8期67卷 2606-2613页

作者： yuzhen Ning Zhihong Zhao Shuang Ben Qiang Li Cunming yu Xudong Zhang Huawei Chen Kesong Liu Lei Jiang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology School of ChemistryBeihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China School of Materials Science and Engineering Shenyang Ligong UniversityShenyang 110159China Tianmushan Laboratory Hangzhou 310023China The Analysis Testing CenterBeihang UniversityBeijing 100191China

The impact of underwater bubbles on solid surfaces with a gradient wettability is important for fundamental science and technological applications. Despite progress in the translational motion of underwater bubbles on asymmetric surface, a fundamental dynamic understanding of asymmetrical bounce behavior of the underwater bubble needs to be further ***, we investigate asymmetrical bounce of underwater bubbles after impacting the wettability gradient copper mesh *** bounce of the underwater bubble on the wettability gradient mesh(WGM) surface is composed by asymmetrical spread in the spread process and asymmetrical recoil in the recoil process, which induce the unidirectional movement ***, effective bubble-size manipulation can be easily implemented due to different volumes of bubbles remaining at different locations of WGM surface. We envision that this work will provide a new understanding of asymmetrical bounce behavior of the underwater bubble on the wettability gradient surface, and propose a novel and feasible strategy for constructing the underwater bubble manipulation system.

关键词： asymmetrical bounce unidirectional movement behavior gradient wettability

Application of CFD and FEA Coupling to Predict Structural Dynamic Responses of A Trimaran in Uni-and Bi-Directional Waves

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china Ocean Engineering 2024年第1期38卷 81-92页

作者： LIAO Xi-yu XIA Jin-song CheN Zhan-yang TANG Qin ZHAO Nan ZHAO Wei-dong GUI Hong-bin Marine Design&Research Institute of china Shanghai 200011China Ship Structure Division China Ship Scientific Research CenterWuxi 214082China College of Ocean Engineering Harbin Institute of TechnologyWeihaiWeihai 264209China State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of TechnologyDalian 116024China School of Foreign Studies Jiangnan UniversityWuxi 214122China

To predict the wave loads of a flexible trimaran in different wave fields,a one-way interaction numerical simulation method is proposed by integrating the fluid solver(Star-CCM+)and structural solver(Abaqus).Differing from the existing coupled CFD-FEA method for monohull ships in head waves,the presented method equates the mass and stiffness of the whole ship to the hull shell so that any transverse and longitudinal section stress of the hull in oblique waves can be ***,verification study and sensitivity analysis are carried out by comparing the trimaran motions using different mesh sizes and time step *** on the wave elevation of uni-and bi-directional waves is also carried *** a comprehensive analysis on the structural responses of the trimaran in different uni-directional regular wave and bi-directional cross sea conditions is carried out,***,the differences in structural response characteristics of trimaran in different wave fields are *** results show that the present method can reduce the computational burden of the two-way fluid-structure interaction simulations.

关键词： CFD-FEA fluid-structure coupling structural responses trimaran bi-directional cross sea