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Phase field modeling of the aspect ratio dependent functional properties of NiTi shape memory alloys with different grain sizes

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Acta Mechanica Sinica 2025年第1期41卷 22-41页

作者： Bo Xu Beihai huang Chong Wang Qingyuan Wang Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan ProvinceSichuan UniversityChengdu 610065China Department of Mechanical Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China Key Laboratory of Deep Underground Science and Engineering(Sichuan University) Ministry of EducationChengdu 610065China

It is well known that coarse-grained super-elastic NiTi shape memory alloys(SMAs)exhibit localized rather than homogeneous martensite transformation(MT),which,however,can be strongly influenced by either internal size(grain size,GS)or the external size(geometric size).The coupled effect of GS and geometric size on the functional properties has not been clearly understood *** this work,the super-elasticity,one-way,and stress-assisted two-way shape memory effects of the polycrystalline NiTi SMAs with different aspect ratios(length/width for the gauge section)and different GSs are investigated based on the phase field *** coupled effect of the aspect ratio and GS on the functional properties is adequately *** simulated results indicate that when the aspect ratio is lower than about 4:1,the stress biaxiality and stress heterogeneity in the gauge section of the sample become more and more obvious with decreasing the aspect ratio,which can significantly influence the microstructure evolution in the process involving external ***,the corresponding functional property is strongly dependent on the aspect *** decreasing the GS and the aspect ratio(to be lower than 4:1),both the aspect ratio and GS can affect the MT or martensite reorientation in each grain and the interaction among ***,due to the strong internal constraint(i.e.,the constraint of grain boundary)and the external constraint(i.e.,the constraint of geometric boundary),the capabilities of the functional properties of NiTi SMAs are gradually weakened and highly dependent on these two factors.

关键词： Phase field modeling NiTi Aspect ratio Grain size Functional property

基于自适应特征模式分解与联合卷积的UUV辐射噪声识别方法

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控制与决策 2025年第1期40卷 155-161页

作者：肖启阳黄澳飞金勇魏倩河南大学人工智能学院郑州450046

针对水下小型UUV难以检测识别问题,提出基于自适应特征模式分解与联合卷积网络的UUV辐射噪声识别方法.首先,采用自适应特征模式分解(AFMD)对信号进行处理,获取一系列分解分量,根据基尼指数(GiNi index)选取最优分量进行重构;然后,对重... 详细信息

针对水下小型UUV难以检测识别问题,提出基于自适应特征模式分解与联合卷积网络的UUV辐射噪声识别方法.首先,采用自适应特征模式分解(AFMD)对信号进行处理,获取一系列分解分量,根据基尼指数(GiNi index)选取最优分量进行重构;然后,对重构后的信号进行连续小波变换,获取不同类型辐射噪声的二维时频图;最后,在频率动态卷积模块和SGE (spatial group-wise enhance)模块基础上,引入特征融合模块构建联合卷积神经网络(JCNN),利用所设计网络提取二维时频图特征,实现水下无人潜水器辐射噪声分类.实验结果表明,所提出方法能够对水下UUV辐射噪声进行识别,且识别率较高.

关键词：水下辐射噪声自适应特征模式分解联合卷积神经网络噪声识别

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基于遗传算法的氨燃料活塞轨迹燃烧优化控制

内燃机学报 2025年第1期43卷 11-19页

作者：李家齐张宸肖进黄震上海交通大学动力机械与工程教育部重点实验室上海200240 上海交通大学智慧能源创新学院上海200240

利用基于重复控制的主动控制器“虚拟曲轴”,在自由活塞发动机中实现了同一压缩比下的不同活塞轨迹运行特征(以参数Ω表征,为生成轨迹的椭圆的短轴与长轴之比),并从指示热效率、峰值压力位置、着火延迟和氮氧化物排放等特征的分析中,获... 详细信息

利用基于重复控制的主动控制器“虚拟曲轴”,在自由活塞发动机中实现了同一压缩比下的不同活塞轨迹运行特征(以参数Ω表征,为生成轨迹的椭圆的短轴与长轴之比),并从指示热效率、峰值压力位置、着火延迟和氮氧化物排放等特征的分析中,获得了参数Ω表征的最优活塞轨迹.以此轨迹作为进一步优化的初始条件,基于遗传算法,以指示热效率为优化目标,对活塞轨迹进行了全局寻优设计.研究结果表明:活塞运动轨迹的变化会影响氨的均质压燃过程.经过寻优设计得出的最优轨迹相较于传统内燃机能够提升3.35%的指示热效率,并减小了42.93%的着火延迟时间.

关键词：自由活塞发动机氨燃烧控制遗传算法

The GECAM ground search system for gamma-ray transients

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Science China(Physics,Mechanics & Astronomy) 2025年第3期Mechanics & Astronomy) .卷 165-178页

作者： Ce Cai Yan-Qiu Zhang Shao-Lin Xiong Ping Wang Jian-Hui Li xiao-Bo Li Cheng-Kui Li Yue huang Shi-Jie Zheng Li-Ming Song Shuo xiao Qi-Bin Yi Yi Zhao Sheng-Lun Xie Rui Qiao Yan-Qi Du Zhi-Wei Guo Wang-Chen Xue Chao Zheng Jia-Cong Liu Chen-Wei Wang Wen-Jun Tan Yue Wang Jin-Peng Zhang Chao-Yang Li Guo-ying Zhao xiao-Yun Zhao xiao-Lu Zhang Zhen Zhang Wen-Xi Peng Xiang Ma Jing-Yan Shi Dong-Ya Guo Jin Wang Xin-Qiao Li Xiang-Yang Wen Zheng-Hua An Fan Zhang College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal University Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences University of Chinese Academy of Sciences School of Physics and Electronic Science Guizhou Normal University Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal University School of Physics and Optoelectronics Xiangtan University School of Computer and Information Dezhou University Institute of Astrophysics Central China Normal University

In the era of time-domain, multi-messenger astronomy, the detection of transient events on the high-energy electromagnetic sky has become more important than ever. The gravitational wave high-energy electromagnetic counterpart all-sky monitor（GECAM）is a dedicated mission to monitor gamma-ray transients, launched in December, 2020. A real-time on-board trigger and location software, using the traditional signal-to-noise ratio（SNR） method for blind search, is constrained to relatively bright signals due to the limitations in on-board computing resources and the need for real-time search. In this work, we developed a ground-based pipeline for GECAM to search for various transients, especially for weak bursts missed by on-board software. This pipeline includes both automatic and manual mode, offering options for blind search and targeted search. The targeted search is specifically designed to search for interesting weak bursts, such as gravitational wave-associated gamma-ray bursts（GRBs）. From the ground search of the data in the first year, GECAM has been triggered by 54 GRBs and other transients, including soft gamma-ray repeaters, X-ray binaries, solar flares, terrestrial gamma-ray flashes. We report the properties of each type of triggers, such as trigger time and light curves. With this search pipeline and assuming a soft Band spectrum, the GRB detection sensitivity of GECAM is increased to about 1.1 × 10-8erg cm-2s-1（10-1000 ke V, burst duration of 20 s）. These results demonstrate that the GECAM ground search system（both blind search and targeted search） is a versatile pipeline to recover true astrophysical signals which were too weak to be found in the on-board search.

关键词： gamma-ray sources gravitational waves data analysis gamma-ray telescopes

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Blue LED-pumped efficient NIR luminescence in Sb3+-doped lead-free metal halides

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Science China Materials 2025年

作者： xiaoyong huang College of Physics and Optoelectronics Taiyuan University of Technology

Broadband near-infrared （NIR） light sources hold promise for some important NIR spectroscopy applications such as night vision,plant growths,optical communications,remote sensing,biomedical imaging and other noninvasive and nondestructive detections[1–4].Recently,the phosphors-converted NIR lightemitting diodes （LEDs） based on“blue LED chips+broadband NIR phosphors”are widely developed for next-generation costeffective NIR light *** this respect,the performance of NIR phosphors directly determines the overall quality of phosphors-converted NIR LEDs.

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基于二极管整流单元的海上风电柔性低频送出系统黑启动策略

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高电压技术 2025年第1期51卷 346-355,I0039页

作者：黄莹黄小威肖晃庆刘涛浙江大学电气工程学院杭州310027 华南理工大学电力学院广州510641 直流输电技术全国重点实验室(中国南方电网科学研究院有限责任公司) 广州510663

在基于二极管整流单元(diode rectifier unit,DRU)的海上风电柔性低频送出系统中,DRU无法向海上风电场传输有功功率,需要额外的黑启动电源为风电机组提供启动所需的初始能量。为此,提出了一种采用辅助换流器作为黑启动电源的海上风电柔... 详细信息

在基于二极管整流单元(diode rectifier unit,DRU)的海上风电柔性低频送出系统中,DRU无法向海上风电场传输有功功率,需要额外的黑启动电源为风电机组提供启动所需的初始能量。为此,提出了一种采用辅助换流器作为黑启动电源的海上风电柔性低频送出系统黑启动策略。首先,介绍了基于DRU的海上风电柔性低频送出系统的拓扑结构与风电机组稳态时的构网型控制策略。然后,基于上述控制策略设计了辅助换流器与风电机组的黑启动策略。在此基础上,分析了辅助换流器容量的选择方法。最后,在时域仿真软件PSCAD/EMTDC上搭建了相应的仿真模型,对系统的黑启动过程进行仿真,仿真中海上风电场所有电气量均能平稳达到正常运行前的状态。仿真结果表明,所提黑启动策略可以实现基于DRU的海上风电柔性低频送出系统的平滑启动。

关键词：海上风电低频交流输电二极管整流单元辅助换流器构网型风电机组黑启动

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Proton transport in unsintered BaCe_(0.8)Y_(0.2)O_(3)-α for easily prepared electrochemical devices

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Journal of Rare Earths 2025年第1期43卷 133-145,I0006页

作者： Xi Wang Yushi Ding ying Li Gaopeng Zhou Wenlong huang Liaoning Key Laboratory for Metallurgical Sensor Material and Technology School of MetallurgyNortheastern UniversityShenyang110819China

BaCe_(0.8)Y_(0.2)O_(3)-αceramics exhibit superior conductivity among related ***,the hightemperature sintering makes it difficult to prepare electrochemical devices with a BaCe_(0.8)Y_(0.2)O_(3)-αmultilayer film,and very few studies have examined the conductivity and transport properties of unsintered BaCe_(0.8)Y_(0.2)O_(3)-α.In nominally dry conditions,the instability of this material in a watercontaining atmosphere can be minimized,allowing the unsintered BaCe_(0.8)Y_(0.2)O_(3)-αto be applied in some particular test environment as a component of electrochemical ***,the conductivity of unsintered BaCe_(0.8)Y_(0.2)O_(3)-αin dry conditions was measured via AC impedance spectroscopy in the temperature range of 500-800℃.The unsintered BaCe_(0.8)Y_(0.2)O_(3)-αexhibits high conductivity and hydration ability,as well as low proton activation *** addition,it shows high oxygen vacancy and low proton transport numbers at high temperature,limited by its grain *** work provides insights into the conductivity and proton transport of unsintered BaCe_(0.8)Y_(0.2)O_(3)-αand demonstrates its potential as a proton-conducting electrolyte.

关键词： Protonic conductor Unsintered material BaCe_(0.8)Y_(0.2)0^(3-α) Conductivity Transport number Rare earths

Efficient activation of peroxymonosulfate for catalytic degradation of organic pollutants by simultaneously using low-level cobalt ions and calcium carbonate micro-particles

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Journal of Environmental Sciences 2025年第5期151卷 113-124页

作者： Yu Zhou xiaobo Wang Nan Wang Shuangshuang huang Lihua Zhu College of Chemistry and Chemical Engineering Huazhong University of Science and TechnologyWuhan 430074China College of Chemistry and Chemical Engineering Hubei Polytechnic UniversityHuangshi 435003China College of Chemistry and Environmental Engineering Wuhan Polytechnic UniversityWuhan 430023China School of Physics and Technology Center for Electron MicroscopyWuhan UniversityWuhan 430072China

An efficient catalytic system was developed to remove various organic pollutants by simultaneously using low-level cobalt ions,calcium carbonate micro-particles and peroxymonosulfate(PMS).A simple base-induced precipitation was used to successfully loaded Co-centered reactive sites onto the surface of CaCO_(3)*** optimal conditions at 25°C,10 mg/L methylene blue(MB)could be completely degraded within 10 min with 480μg/L Co^(2+),0.4 g/L CaCO_(3)microparticles(or 0.4 g/L Co@CaCO_(3))and 0.1 g/L *** MB degradation followed the pseudo first order kinetics with a rate constant of 0.583 min^(−1),being 8.3,11.5 and 53.0 times that by using Co-OH(0.07 min^(−1)),Co^(2+)(0.044 min^(−1))and CaCO_(3)(0.011 min^(−1))as the catalyst,*** was confirmed that there was a synergistic effect in the catalytic activity between Co species and the CaCO_(3)particles but the major contributor was the highly dispersed Co *** Co^(2+)-containing simulated electroplating wastewater was used as the Co^(2+)source,not only the added MB was also completely degraded within 5 min in this catalytic system,but also the coexisting heavy metal ions were substantially *** presently developed method was applied to simultaneously treat organic wastewater and heavy metals *** present method was also successfully used to efficiently degrade other organic pollutants including bisphenol A,sulfamethoxazole,rhodamine B,tetrabromobisphenol A,ofloxacin and benzoic acid.A catalytic mechanism was proposed for the PMS activation by Co@CaCO_(3).The surface of CaCO_(3)particles favors the adsorption of Co^(2+).More importantly,the surface of CaCO_(3)particles provides plentiful surface-OH and-CO_(3)^(2+),and these surface groups complex with Co^(2+)to producemore catalytically active species such as surface[CoOH]^(−),resulting in rapid Co^(2+)/Co^(3+)cycling and electron *** interactions cause the observed synergistic effect between Co species and Ca

关键词： CaCO3 Low-level cobalt Peroxymonosulfate Oxidative degradation

An Online Exploratory Maximum Likelihood Estimation Approach to Adaptive Kalman Filtering

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IEEE/CAA Journal of Automatica Sinica 2025年第1期12卷 228-254页

作者： Jiajun Cheng Haonan Chen Zhirui Xue Yulong huang Yonggang Zhang the College of Intelligent Systems Science and Engineering Harbin Engineering University the Engineering Research Center of Navigation Instruments Ministry of Education the College of Intelligent Systems Science and Engineering the College of Future Technology Harbin Engineering University IEEE

Over the past few decades, numerous adaptive Kalman filters(AKFs) have been proposed. However, achieving online estimation with both high estimation accuracy and fast convergence speed is challenging, especially when both the process noise and measurement noise covariance matrices are relatively inaccurate. Maximum likelihood estimation(MLE) possesses the potential to achieve this goal, since its theoretical accuracy is guaranteed by asymptotic optimality and the convergence speed is fast due to weak dependence on accurate state ***, the maximum likelihood cost function is so intricate that the existing MLE methods can only simply ignore all historical measurement information to achieve online estimation,which cannot adequately realize the potential of MLE. In order to design online MLE-based AKFs with high estimation accuracy and fast convergence speed, an online exploratory MLE approach is proposed, based on which a mini-batch coordinate descent noise covariance matrix estimation framework is developed. In this framework, the maximum likelihood cost function is simplified for online estimation with fewer and simpler terms which are selected in a mini-batch and calculated with a backtracking method. This maximum likelihood cost function is sidestepped and solved by exploring possible estimated noise covariance matrices adaptively while the historical measurement information is adequately utilized. Furthermore, four specific algorithms are derived under this framework to meet different practical requirements in terms of convergence speed, estimation accuracy,and calculation load. Abundant simulations and experiments are carried out to verify the validity and superiority of the proposed algorithms as compared with existing state-of-the-art AKFs.

关键词： Adaptive Kalman filtering coordinate descent maximum likelihood estimation mini-batch optimization unknown noise covariance matrix