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Nonreciprocity of energy transfer in a nonlinear asymmetric oscillator system with various vibration states

Applied Mathematics and Mechanics(English Edition) 2023年第5期44卷 727-744页

作者： Jian’en CHEN Jianling LI Minghui YAO jun liu Jianhua ZHANG Min SUN Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical EngineeringTianjin University of TechnologyTianjin 300384China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of TechnologyTianjin 300384China School of Aeronautics and Astronautics Tiangong UniversityTianjin 300387China Agricultural Information Institute of Chinese Academy of Agricultural Sciences Key Laboratory of Agricultural Big DataMinistry of Agriculture and Rural AffairsBeijing 100081China School of Science Tianjin Chengjian UniversityTianjin 300384China

The nonreciprocity of energy transfer is constructed in a nonlinear asymmetric oscillator system that comprises two nonlinear oscillators with different parameters placed between two identical linear *** slow-flow equation of the system is derived by the complexification-averaging *** semi-analytical solutions to this equation are obtained by the least squares method,which are compared with the numerical solutions obtained by the Runge-Kutta *** distribution of the average energy in the system is studied under periodic and chaotic vibration states,and the energy transfer along two opposite directions is *** effect of the excitation amplitude on the nonreciprocity of the system producing the periodic responses is analyzed,where a three-stage energy transfer phenomenon is *** the first stage,the energy transfer along the two opposite directions is approximately equal,whereas in the second stage,the asymmetric energy transfer is *** energy transfer is also asymmetric in the third stage,but the direction is reversed compared with the second ***,the excitation amplitude for exciting the bifurcation also shows an asymmetric *** vibrations are generated around the resonant frequency,irrespective of which linear oscillator is *** excitation threshold of these chaotic vibrations is dependent on the linear oscillator that is being *** addition,the difference between the energy transfer in the two opposite directions is used to further analyze the nonreciprocity in the *** results show that the nonreciprocity significantly depends on the excitation frequency and the excitation amplitude.

关键词： nonreciprocity strong nonlinearity energy transfer chaotic vibration higher branch of response

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Al−10Nb−3Ce−2.5B孕育剂对Zn−Al共析合金显微组织、阻尼和拉伸力学性能的影响

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Transactions of Nonferrous Metals Society of China 2024年第2期34卷 465-479页

作者：张建军殷福星余晖冀璞光刘力李玉芳焦志娴王清周河北工业大学材料科学与工程学院天津市材料层状复合与界面控制技术重点实验室天津300130 广东省科学院新材料研究所广州510651

制备一种新型Al−10Nb−3Ce−2.5B孕育剂,并系统研究其对锌铝共析(ZA22)合金显微组织、阻尼和拉伸力学性能的影响。结果表明,该孕育剂对ZA22合金中的α相具有显著的细化作用(α相最低可被细化至约16μm),并可使得α相的形貌从粗大枝晶状转... 详细信息

制备一种新型Al−10Nb−3Ce−2.5B孕育剂,并系统研究其对锌铝共析(ZA22)合金显微组织、阻尼和拉伸力学性能的影响。结果表明,该孕育剂对ZA22合金中的α相具有显著的细化作用(α相最低可被细化至约16μm),并可使得α相的形貌从粗大枝晶状转变为细小花瓣状。通过边−边匹配晶体学模型(E2EM)建立孕育剂中CeB_(6)和NbB_(2)颗粒与α相之间的位向关系(ORs),并基于该E2EM模型揭示孕育剂对ZA22合金的细化机理。与未细化ZA22合金相比,孕育细化ZA22合金的高温阻尼性能,特别是逆共析转变阻尼峰得到显著提升。此外,孕育细化ZA22合金的室温拉伸力学性能也得到了显著提高,具有最佳细化效果的ZA22合金的抗拉强度和伸长率分别比未细化ZA22合金的高18.56%和119.04%。对相关机理进行了讨论。

关键词： Zn−Al共析合金孕育剂显微组织细化阻尼拉伸力学性能

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Computational Simulation and Electrochemically Deposited Molecularly Imprinted Polymer-coated Carbon Glass Electrode for Triclosan Detection

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Chinese Journal of Structural Chemistry 2020年第7期39卷 1252-1260页

作者： GAO Bo TANG Shan-Shan liu jun-Bo JIN Rui-Fa College of Resources and Environment Jilin Agricultural UniversityChangchun 130118China College of Chemistry and Chemical Engineering Chifeng UniversityChifeng 024000China

Triclosan,a kind of multi-purpose biocide,was widely used household cleaning and personal care *** widespread use of triclosan has potential risk to the ecotype and human health due to its release into sediment,surface and ground water resources.A molecularly imprinted electrochemical sensor for triclosan detection in cosmetic emulsion was synthesized and *** order to determine the suitable monomer and evaluate the template-monomer geometry as well as the interaction energy in the template-monomer prepolymerization mixture,a computational study was *** found that the complex formed by hybrid monomers(triclosan(o-phenylenediamine-co-resorcinol))had more hydrogen bonds and larger binding energy than that by single kind of monomers(triclosan(o-phenylenediamine)2 and triclosan(resorcinol)2).Therefore,hybrid monomers were used to synthesize the imprinted electrochemical sensor,which exhibits a high sensitivity and selectivity for triclosan sensing with the detection range 0~15 ng·mL-1 and detection limit 0.41 ng·mL-1.

关键词： computational simulation electrochemical synthesis molecular imprinting triclosan hybrid monomers

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Temporal stability analysis of soil moisture along a coniferous forest hillslope with subtropical monsoon climate in southwest China

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Journal of Mountain Science 2021年第11期18卷 2900-2914页

作者： BAI Yu-shi liu Mu-xing YI jun ZHANG Hai-lin Hubei Province Laboratory for Geographical Process Analyzing&Modeling Wuhan 430079China College of Urban and Environmental Sciences Central China Normal UniversityWuhan 430079China Research Institute of Sustainable Development Central China Normal UniversityWuhan 430079China

Soil water content(SWC)plays a crucial role in simulating hydrological process,guiding reforestation and controlling soil erosion in mountainous ***-temporal variability of SWC increases the difficulty of quantifying SWC pattern in the prediction of soil *** stability analysis of SWC can reduce the labor consuming and simplify the costly field *** study aimed to evaluate the temporal stability of SWC at hourly,daily and monthly temporal periods and its controlling factors at a hillslope in the Three Gorges *** SWC of five soil depths was monitored at 5 topographic locations(toe,lower,middle,upper and top slope positions)along a 170 m hillslope in the Three Gorges region(110°04'~112°04'E,29°53'~31°34'N),Yichang City,Hubei Province,China from May 4^(th),2018 to May 3^(rd),*** results showed thatthe coefficient of variation of SWC ranged from 4%to 49%,which increased with rising soil depth within 40 cm but thereafter ***,the high Spearman's rank coefficients(P<0.05)indicated strong temporal stability at three temporal *** locations(RLs)varied in the different soil depths,which weretoe,upper and middle slope positions at 0~40,40~60 and 60~80 cm depthsof the investigated hillslope,*** hydraulic conductivity served as adominant factor controlling the temporal stability of *** result advances our thorough understanding of hydrology and soil water resource in the Three Gorges region.

关键词： Soil water content Temporal stability Representative location Hillslope hydrology Temporal period Three Gorges region

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Neoarchean Magmatic Events in the Western Songnen Massif,Central Asian Orogenic Belt:Timing and Tectonic Significance

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Acta Geologica Sinica(English Edition) 2023年第2期97卷 436-448页

作者： WU Xinwei liu Zhenghong liu Yongjiang ZHANG Chao SHAO jun ZHANG Chao ZHANG Yujin GUO Wei liu Baoshan ZHANG Guangyu Shenyang Center of China Geological Survey Shenyang 110034China Key Laboratory of Deep Mineral Resources Exploration and Evaluation Department of Natural Resource of Liaoning ProvinceShenyang 110034China College of Earth Sciences Jilin UniversityChangchun 130061China Frontiers Science Center for Deep Ocean Multispheres and Earth System Key Laboratory of Submarine Geosciences and Prospecting TechniquesMOE and College of Marine GeosciencesOcean University of ChinaQingdaoShandong 266100China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao Shandong 266100China School of Resources and Environmental Engineering Shandong University of TechnologyZiboShandong 255049China

Whether a Neoarchean basement existing in the Songnen massif is currently *** of Archean magmatism from the Songnen Massif is helpful to resolve this ***,we report newly discovered Neoarchean Shanquan pluton in the Western Songnen *** Neoarchean Shanquan pluton are mainly composed of granites that are exposed near the town of Shanquan in Heilongjiang ***-ICP-MS zircon U-Pb dating reveals that the sample 2015TW1 has an upper intercept age of 2801±69 Ma and a weighted mean age of 2708±18 Ma,while samples LJ27QY1 and LJ27QY2 have upper intercept ages of 2677±57 Ma and 2653±18 Ma,and weighted mean ages of 2649±10 Ma and 2653±15 Ma,*** indicates that these granites were formed at~2.7 *** of the~2.7 Ga zircons have older TDM2 ages of 2762–3326 Ma with positiveεHf(t)values ranging from 0 to 6.4,while a few of the zircons have negativeεHf(t)values ranging from-8.1 to-11.5 and older TDM2 ages varying from 3158 to 3264 *** zircon Hf isotopes indicate that Paleo-Mesoarchean crusts might once existed in the Songnen Massif,and the studied Neoarchean magmas were principally derived from partial melting of these Paleo-Mesoarchean ancient *** on the geochronological spectrum of magmatic and detrital zircons,the Songnen,Erguna,Jiamusi,Bureya massifs may have a common basement prior to the Neoproterozoic and may even be linked with the Triam Craton.

关键词： tectonic attribute Neoarchean magmatism Precambrian basement Longjiang area Songnen Massif

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深度学习重建算法对肾上腺肿瘤的检出及鉴别效能的影响

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放射学实践 2024年第8期39卷 1081-1088页

作者：王诗耕刘义军童小雨范勇李贝贝王旭崔景景陈安良大连医科大学附属第一医院放射科辽宁大连116011 联影智能医疗科技(北京)有限公司北京100094

目的:探讨不同等级深度学习图像重建(DLIR)算法对肾上腺肿瘤的检出、组学特征可重复性和组学模型鉴别肿瘤类型效能的影响。方法:回顾性收集41例肾上腺功能性腺瘤(FAA)和46例肾上腺转移瘤(AM)患者的临床和影像资料。CT增强扫描完成后,对... 详细信息

目的:探讨不同等级深度学习图像重建(DLIR)算法对肾上腺肿瘤的检出、组学特征可重复性和组学模型鉴别肿瘤类型效能的影响。方法:回顾性收集41例肾上腺功能性腺瘤(FAA)和46例肾上腺转移瘤(AM)患者的临床和影像资料。CT增强扫描完成后,对静脉期的原始数据采用4种强度等级(DL1、DL2、DL3、DL4)的DLIR算法进行重建。首先采用主、客观指标比较4种等级间图像质量的差异;然后使用Research Portal V1.1科研平台对各组重建图像上肾上腺肿瘤进行分割并提取450个影像组学特征,包括原始图像特征90个和拉普拉斯(LoG)滤波后的高阶特征(高斯核:0.5、1.0、1.5、2.0)360个。采用一致性相关系数(CCC)评估采用不同图像重建等级测量的FAA和AM组学特征的可重复性。最后,在各组重建图像中采用逐步特征选择策略,筛选出最优特征集并构建鉴别FAA和AM的组学模型。利用五折交叉验证法验证4个组学模型的鉴别效能,利用分层交叉验证法测评4个模型的泛化能力。结果:DL2和DL3在肾显示上腺肿瘤的清晰度方面最优,得分为4(4,5),优于DL1相应得分4(3,5)和DL4相应得分4(3,4),且差异具有统计学意义(F=139.045,P0.85的个数逐渐减少,DL4中FAA和AM特征可重复的比例仅占39.3%(21/90)和50.9%(29/90)。组学特征经过LoG滤波(高斯核2.0)处理后,CCC值>0.85的个数增加,DL4中FAA和AM特征可重复的比例占91.1%(82/90)和93.3%(84/90)。4个组学模型在测试集中的曲线下面积(AUC)和符合率均>0.75,DeLong检验显示AUC的差异无统计学意义(Z=0.177~1.284,P=0.199~0.859)。但分层交叉验证显示,DL4重建图像的泛化能力最弱,AUC和符合率均<0.75。结论:高降噪等级的DLIR算法会降低对肾上腺肿瘤显示的清晰度以及组学模型的泛化性。虽然LoG滤波器(高斯核:2.0)有助于提升组学特征测量的可重复性,但仍建议在肾上腺影像诊断和组学模型训练时,使用中低降噪等级的DLIR图像。

关键词：体层摄影术,X线计算机影像组学深度学习重建算法肾上腺肿瘤可重复性

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Event-triggered Control of Positive Switched Systems with Actuator Saturation and Time-delay

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International Journal of Automation and computing 2021年第1期18卷 141-154页

作者： jun-Feng Zhang Lai-You liu Shi-Zhou Fu Shuo Li School of Automation Hangzhou Dianzi UniversityHangzhou 310018China Inria University of LilleLille 59000France

This paper investigates the event-triggered control of positive switched systems with randomly occurring actuator saturation and time-delay,where the actuator saturation and time-delay obey different Bernoulli ***,an event-triggering con-dition is constructed based on a 1-norm *** the presented event-triggering scheme,an interval estimation method is utilized to deal with the error term of the *** a co-positive Lyapunov functional,the event-triggered controller and the cone attraction domain gain matrices are designed via matrix decomposition *** positivity and stability of the resulting closed-loop systems are reached by guaranteeing the positivity of the lower bound of the systems and the stability of the upper bound of the systems,*** proposed approach is developed for interval and polytopic uncertain systems,***,two examples are provided to illustrate the effectiveness of the theoretical findings.

关键词： Positive switched systems event-triggered control randomly occurring actuator saturation linear programming time-delay

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电池衰减诊断及状态评估研究进展

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Science China Materials 2024年第4期67卷 1014-1041页

作者：袁君秦之理黄海坤甘兴栋王子为杨毅琛刘书江文安毕闯李白海孙成华 School of Materials and Energy University of Electronic Science and Technology of China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of China School of Computer Science and Engineering University of Electronic Science and Technology of China Power Research Institute of State Grid Shaanxi Electric Power Company Limited Department of Chemistry and Biotechnology Swinburne University of Technology

锂离子电池(LIB)广泛应用于储能及动力输出等领域.准确预测电池的健康状态对于优化性能、降低运营费用和防止电池故障等方面具有重要的意义.本文对预测LIB的荷电状态(SOC)、健康状态(SOH)和剩余使用寿命(RUL)方面的最新发展进行了全面回... 详细信息

锂离子电池(LIB)广泛应用于储能及动力输出等领域.准确预测电池的健康状态对于优化性能、降低运营费用和防止电池故障等方面具有重要的意义.本文对预测LIB的荷电状态(SOC)、健康状态(SOH)和剩余使用寿命(RUL)方面的最新发展进行了全面回顾,重点关注机器学习技术方面的研究进展,深入分析了LIB的退化机制及其基本理论,评估了各种传统方法及机器学习技术在预测SOC,SOH和RUL方面的优势和限制.此外,还探讨了电动汽车动力电池在实际应用中面临的挑战,特别是性能退化问题.最后提出了对LIB未来研究方向有价值的见解.尽管机器学习方法在提高预测SOC,SOH和RUL准确性方面具有巨大潜力,但在实际应用中仍然有许多技术和实际障碍需要克服.

关键词：锂离子电池剩余使用寿命状态评估机器学习技术健康状态动力输出运营费用退化机制

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A novel high precision Doppler frequency estimation method based on the third-order phase-locked loop

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Research in Astronomy and Astrophysics 2021年第9期21卷 83-90页

作者： Tao Deng Mao-Li Ma Qing-Hui liu Ya-jun Wu Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China University of Chinese Academy of Sciences Beijing 100049China

In deep space exploration,many engineering and scientific requirements require the accuracy of the measured Doppler frequency to be as high as *** our paper,we analyze the possible frequency measurement points of the third-order phase-locked loop(PLL)and find a new Doppler measurement *** on this finding,a Doppler frequency measurement algorithm with significantly higher measurement accuracy is *** the actual data processing,compared with the existing engineering software,the accuracy of frequency of 1 second integration is about 5.5 times higher when using the new *** improved algorithm is simple and easy to *** improvement can be easily combined with other improvement methods of PLL,so that the performance of PLL can be further improved.

关键词： Doppler frequency measurement:deep space exploration:carrier tracking:phase locked loop:high precision

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Enhancing room-temperature thermoelectric performance of n-type Bi_(2)Te_(3)-based alloys via sulfur alloying

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Rare Metals 2021年第3期40卷 513-520页

作者： Feng liu Ye-Hao Wu Qi Zhang Tie-jun Zhu Xin-Bing Zhao State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China

Bismuth-telluride-based alloys are the best thermoelectric materials used in commercial solid-state refrigeration near room ***,for n-type polycrystalline alloys,their thermoelectric figure of merit(zT) values at room temperature are often less than1.0,due to the high electron concentration originating from the donor-like effect induced by the mechanical deformation ***,carrier concentration for better performance near room temperature was optimized through manipulating intrinsic point defects by sulfur *** alloying significantly decreases antisite defects concentration and suppresses donor-like effect,resulting in optimized carrier concentration and reduced electronic thermal *** hot deformation process was also applied to improve carrier mobility due to the enhanced *** a result,a high zT value of 1 at 300 K and peak zT value of 1.1 at 350 K were obtained for the twice hot-deformed Bi_(2) Te_(2.7)Se_(0.21)S_(0.09) sample,which verifies sulfur alloying is an effective method to improve thermoelectric performance of n-type polycrystalline Bi2 Te3-based alloys near room temperature.

关键词： Bismuth telluride Thermoelectric Point defect Sulfur alloying Hot deformation

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