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An adaptive hyper parameter tuning model for ship fuel consumption prediction under complex maritime environments

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Journal of Ocean Engineering and Science 2022年第3期7卷 255-263页

作者： Tianrui Zhou Qinyou hu zhihui hu Rong Zhen Merchant Marine College Shanghai Maritime University1550 Haigang AvenuePudong New AreaShanghaiChina Navigation College Jimei UniversityXiamen 361021FujianChina

An accurate prediction of ship fuel consumption is critical for speed,trim,and voyage optimisation etc.While previous studies have focused on predicting ship fuel consumption with respect to a variety of factors,research on the impact of environmental factors on fuel consumption has been lacking.In addition,although recent research efforts have widely focused on machine learning methods to predict fuel consumption,studies on hyperparameter values that are suitable for these prediction models are limited.To compensate for this deficiency in existing literature,an adaptive hyperparameter tuning method is proposed,and the effects of maritime environmental factors on fuel consumption are taken into account.Through experimentation,the proposed adaptive hyperparameter tuning method was validated via artificial neural network(ANN),support vector regression(SVR),random forest(RF),and least absolute shrink-age and selection operator(Lasso).The hyperparameter tuning proportionally increased the amplitudes of the coefficients of determination(R 2)of these algorithms.The increase of the amplitude demonstrated the following trend,in the order of the largest increase to the lowest increase:ANN,Lasso,SVM,and RF.The rates of increase were between 0.0773%and 2.1653%.Furthermore,after the environmental factors were considered,the prediction accuracies of the ANN and Lasso increased;however,the opposite was observed for the SVR and RF.As such,we confirmed that the use of Bayesian optimisation for hyper-parameter tuning can effectively improve the fuel consumption prediction accuracy,and our proposed model can therefore serve as a significant reference for calculating fuel consumption.

关键词： Ship fuel consumption Artificial neural network Bayesian optimization Hyperparameter tuning Environmental factors

Sirtuin 3 regulation:a target to alleviateβ-hydroxybutyric acid-induced mitochondrial dysfunction in bovine granulosa cells

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Journal of Animal Science and Biotechnology 2023年第4期14卷 1377-1394页

作者： Shanjiang Zhao Jianfei Gong Yi Wang Nuo Heng huan Wang zhihui hu Haoyu Wang Haobo Zhang huabin Zhu State Key Laboratory of Animal Nutrition Key Laboratory of Animal GeneticsBreeding and Reproduction of Ministry of Agriculture and Rural AffairsInstitute of Animal ScienceChinese Academy of Agricultural SciencesBeijingChina

Background During the transition period,the insufficient dry matter intake and a sharply increased in energy consumption to produce large quantities of milk,high yielding cows would enter a negative energy balance(NEB)that causes an increase in ketone bodies(KBs)and decrease in reproduction efficiency.The excess concentrations of circulating KBs,represented byβ-hydroxybutyric acid(BHBA),could lead to oxidative damage,which potentially cause injury to follicular granulosa cells(fGCs)and delayed follicular development.Sirtuin 3(Sirt3)regulates mitochondria reactive oxygen species(mitoROS)homeostasis in a beneficial manner;however,the molecular mechanisms underlying its involvement in the BHBA-induced injury of fGCs is poorly understood.The aim of this study was to explore the protection effects and underlying mechanisms of Sirt3 against BHBA overload-induced damage of fGCs.Results Our findings demonstrated that 2.4 mmol/L of BHBA stress increased the levels of mitoROS in bovine fGCs.Further investigations identified the subsequent mitochondrial dysfunction,including an increased abnormal rate of mitochondrial architecture,mitochondrial permeability transition pore(MPTP)opening,reductions in mitochondrial membrane potential(MMP)and Ca^(2+)release;these dysfunctions then triggered the caspase cascade reaction of apoptosis in fGCs.Notably,the overexpression of Sirt3 prior to treatment enhanced mitochondrial autophagy by increasing the expression levels of Beclin-1,thus preventing BHBA-induced mitochondrial oxidative stress and mitochondrial dysfunction in fGCs.Furthermore,our data suggested that the AMPK-mTOR-Beclin-1 pathway may be involved in the protective mechanism of Sirt3 against cellular injury triggered by BHBA stimulation.Conclusions These findings indicate that Sirt3 protects fGCs from BHBA-triggered injury by enhancing autophagy,attenuating oxidative stress and mitochondrial damage.This study provides new strategies to mitigate the fGCs injury caused by excessive BHBA stress in dairy cows with ketosis.

关键词： BHBA Dairy cows Granulosa cells Ketosis Mitochondrial function Sirt3

Experimental and DFT studies of flower-like Ni-doped Mo_(2)C on carbon fiber paper:A highly efficient and robust HER electrocatalyst modulated by Ni(NO_(3))_(2)concentration

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Journal of Advanced Ceramics 2022年第8期11卷 1294-1306页

作者： Lei ZHANG zhihui hu Juntong huANG Zhi CHEN Xibao LIa Zhijun FENG huiyong YANG Saifang huANG Ruiying LUO School of Materials Science and Engineering Nanchang Hangkong UniversityNanchang 330063China School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Research Institute for Frontier Science Beihang UniversityBeijing 100191China

Developing highly efficient and stable non-precious metal catalysts for water splitting is urgently required.In this work,we report a facile one-step molten salt method for the preparation of self-supporting Ni-doped Mo_(2)C on carbon fiber paper(Ni–Mo_(2)CCB/CFP)for hydrogen evolution reaction(HER).The effects of nickel nitrate concentration on the phase composition,morphology,and electrocatalytic HER performance of Ni-doped Mo_(2)C@CFP electrocatalysts was investigated.With the continuous increase of Ni(NO_(3))_(2)concentration,the morphology of Mo_(2)C gradually changes from granular to flower-like,providing larger specific surface area and more active sites.Doping nickel(Ni)into the crystal lattice of Mo_(2)C largely reduces the impedance of the electrocatalysts and enhances their electrocatalytic activity.The as-developed Mo_(2)C–3 M Ni(NO_(3))_(2)/CFP electrocatalyst exhibits high catalytic activity with a small overpotential of 56 mV at a current density of 10 mA·cm^(-2).This catalyst has a fast HER kinetics,as demonstrated by a very small Tafel slope of 27.4 mV·dec^(-1),and persistent long-term stability.A further higher Ni concentration had an adverse effect on the electrocatalytic performance.Density functional theory(DFT)calculations further verified the experimental results.Ni doping could reduce the binding energy of Mo–H,facilitating the desorption of the adsorbed hydrogen(Hads)on the surface,thereby improving the intrinsic catalytic activity of Ni-doped Mo_(2)C-based catalysts.Nevertheless,excessive Ni doping would inhibit the catalytic activity of the electrocatalysts.This work not only provides a simple strategy for the facile preparation of non-precious metal electrocatalysts with high catalytic activity,but also unveils the influence mechanism of the Ni doping concentration on the HER performance of the electrocatalysts from the theoretical perspective.

关键词： Mo_(2)C@CFP electrocatalyst nickel(Ni)doping hydrogen evolution reaction(HER) water splitting molten salt method

Numerical analysis of detaching and wrinkling of mechanically lined pipe during its spooling-on stage to the reel

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Theoretical & Applied Mechanics Letters 2015年第5期5卷 205-209页

作者： Tianfeng Zhao zhihui hu College of Mechanical and Transportation Engineering China University of Petroleum Engineering Design Institute CNPC Offshore Engineering Company Limited

The structural behavior of mechanically lined pipes （MLPs） during the spooling-on phase is investigated in this paper, motivated by their promising offshore applications relying on reel installation. By applying quasi 2D models, we first investigated the gripping stresses preserved in the MLP after the hydraulic expansion manufacturing process and the detachment of the liner under spooling-on curvatures. Furthermore, a comparative 3D finite element （FE） analysis for the liner wrinkling behaviors of MLP with different wall thicknesses of outer layers was performed and indicated that when the wall thickness of outer layer increases from 14.3 mm to 17.9 mm, MLP＇s critical spooling-on curvature increased more than 47%, reachin0.1432 rdd/m.

关键词： Mechanically lined pipeDetachingWrinklingSpooling-onCritical curvature

Effects of Y_(2)O_(3) and transition-metal nitrates on phase,microstructures and PL properties of N-containing Ce_(2)Si_(2.5)Al_(0.5)O_(3.5)N_(3.5) melilite

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Journal of Rare Earths 2021年第10期39卷 1282-1288,I0005页

作者： Meng Zhang zhihui hu Zhi Chen Juntong huang Qingming Xiong Renming Shuai Zhijun Feng Xibao Li School of Materials Science and Engineering Nanchang Hangkong UniversityNanchang 330063China

N-containing Ce_(2)Si_(2.5)Al_(0.5)O_(3.5)N_(3.5)(CeSiAlON) melilite was synthesized at 1550 and 1600℃ for 5 h from CeO_(2),Si,Al,and Al_(2)O_(3) in nitrogen by using Y_(2)O_(3) and transition-metal nitrates(Co(NO_(3))_(2)·6 H_(2) O and Ni(NO_(3))_(2)·6 H_(2)O) as additives.The effects of Y_(2)O_(3) and transition-metal nitrates on the phase,microstructures and photoluminescence properties of CeSiAlON melilite were studied.The incorporation of Y_(2)O_(3) can promote the reaction of raw materials to a low degree,and results in a unit cell shrinkage of CeSiAlON due to the smaller radius of Y atom than that of Ce atom.The transition-metal nitrates can accelerate the reaction clearly and facilitate the formation of CeSiAlON fibers.The photoluminescence(PL) properties of CeSiAlON melilite presents a board violet emission band because of the 5 d-4 f transitions of Ce^(3+),and the additives can enhance the PL emission intensities of specimen significantly.

关键词： N-containing Ce_(2)Si_(2.5)Al_(0.5)O_(3.5)N_(3.5)melilite Y_(2)O_(3) Transition-metal nitrates Fiber Photoluminescence properties

Strain-Insensitive Hierarchically Structured Stretchable Microstrip Antennas for Robust Wireless Communication

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Nano-Micro Letters 2021年第8期13卷 1-12页

作者： Jia Zhu Senhao Zhang Ning Yi Chaoyun Song Donghai Qiu zhihui hu Bowen Li Chenghao Xing Hongbo Yang Qing Wang huanyu Cheng Department of Engineering Science and Mechanics The Pennsylvania State UniversityUniversity ParkPA 16802USA Division of Life Sciences and Medicine School of Biomedical Engineering(Suzhou)University of Science and Technology of ChinaHefei 230022People’s Republic of China Institute of Biomedical Engineering and Technology Chinese Academy of ScienceSuzhou 215011People’s Republic of China Department of Materials Science and Engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA School of Engineering and Physical Sciences Heriot-Watt UniversityUniversity ParkEdinburgh EH144ASScotlandUK Department of Electrical Engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA

As the key component of wireless data transmission and powering,stretchable antennas play an indispensable role in flexible/stretchable electronics.However,they often suffer from frequency detuning upon mechanical deformations;thus,their applications are limited to wireless sensing with wireless transmission capabilities remaining elusive.Here,a hierarchically structured stretchable microstrip antenna with meshed patterns arranged in an arched shape showcases tunable resonance frequency upon deformations with improved overall stretchability.The almost unchanged resonance frequency during deformations enables robust on-body wireless communication and RF energy harvesting,whereas the rapid changing resonance frequency with deformations allows for wireless sensing.The proposed stretchable microstrip antenna was demonstrated to communicate wirelessly with a transmitter(input power of−3 dBm)efficiently(i.e.,the receiving power higher than−100 dBm over a distance of 100 m)on human bodies even upon 25%stretching.The flexibility in structural engineering combined with the coupled mechanical-electromagnetic simulations,provides a versatile engineering toolkit to design stretchable microstrip antennas and other potential wireless devices for stretchable electronics.

关键词： Stretchable microstrip antennas Strain-insensitive resonance frequency Wireless communication RF energy harvesting Wearable and bio-integrated electronics

喉癌术后放疗患者复发影响因素及与不同放疗剂量的关系

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中国医学物理学杂志 2024年第2期41卷 158-162页

作者：刘彬胡智慧孔娜李炎陈坤石家庄市人民医院耳鼻咽喉头颈外科河北石家庄050000 石家庄市人民医院肿瘤一科河北石家庄050000 石家庄市第三医院骨科河北石家庄050011

目的:探讨喉癌术后放疗患者复发的影响因素、各术式下不同放疗剂量与复发的关系及对生存率的影响。方法:回顾性分析石家庄市人民医院收治的134例喉癌术后放疗患者临床资料,先对其进行单因素分析,后采用多因素Logistic回归分析术后复发... 详细信息

目的:探讨喉癌术后放疗患者复发的影响因素、各术式下不同放疗剂量与复发的关系及对生存率的影响。方法:回顾性分析石家庄市人民医院收治的134例喉癌术后放疗患者临床资料,先对其进行单因素分析,后采用多因素Logistic回归分析术后复发的危险因素。同时探讨不同放疗剂量与各术式的关系,利用Kaplan-meler法、Log rank检验对喉癌患者2年生存率进行分析。结果:134例患者中,30例术后复发者设为复发组,其余104例为未复发组。经多因素Logistic回归分析可知,临床分期(Ⅲ~Ⅳ期)、T分期(T3~T4期)、N分期(N1~N3)、放疗剂量(低剂量)、甲状腺软骨受侵(是)、手术切缘(阳性)为喉癌术后复发的独立危险因素(OR>1,P11周因素均可影响疾病复发,临床上应当结合患者病情适当调高放疗剂量,以改善预后,延长生存期限。

关键词：喉癌术后放射治疗放射剂量复发生存曲线影响因素

日本都市圈市域铁路敷设方式和线路类型浅析及对我国的启示

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交通与港航 2024年第1期11卷 16-21页

作者：张临辉胡志晖上海市交通发展研究中心

当前我国市域铁路面临重要发展机遇,研究采用何种适宜的建设模式以提高运营效能、降低建设成本成为当前急需研究的热点和难点课题。该文通过简析日本都市圈市域铁路敷设方式和线路类型,总结出不同建设模式的适应性,提出我国市域铁路规... 详细信息

当前我国市域铁路面临重要发展机遇,研究采用何种适宜的建设模式以提高运营效能、降低建设成本成为当前急需研究的热点和难点课题。该文通过简析日本都市圈市域铁路敷设方式和线路类型,总结出不同建设模式的适应性,提出我国市域铁路规划建设中急需理念创新,因地制宜地选择敷设方式和线路类型,采用集约、韧性的建设模式,以应对客流变化和多样化的运营需求,切实提高市域铁路的服务水平,打造轨道上的都市圈,提升城市的竞争力和影响力。

关键词：市域铁路敷设方式地上线线路类型双复线

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基于YOLOv5的微表情识别技术研究

曲阜师范大学学报（自然科学版） 2024年第3期50卷 96-102页

作者：张山山胡志慧湖北汽车工业学院电气与信息工程学院湖北省十堰市442000

针对微表情数据集较少、泛化能力较弱和微表情识别系统对设备要求较高等问题进行研究.对3个主流数据集进行融合筛选,重构了一个多样本表情数据集;采用在微表情数据集中融入部分宏表情的方法解决了模型泛化能力不强的问题;基于YOLOv5模... 详细信息

针对微表情数据集较少、泛化能力较弱和微表情识别系统对设备要求较高等问题进行研究.对3个主流数据集进行融合筛选,重构了一个多样本表情数据集;采用在微表情数据集中融入部分宏表情的方法解决了模型泛化能力不强的问题;基于YOLOv5模型进行训练和测试,获得了相对便于移植的微表情识别系统.结果表明:经过改进数据集训练后的模型泛化能力有所提升;训练好的模型在自己构建的微表情数据集(Z-MES)上的识别准确率达到79.4%,优于改进前的微表情识别效果.

关键词：微表情识别 YOLOv5 数据集