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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 181-195页

作者： Sheng Cao Hongyu Liu Jin Jiang Ke He Binghua Lv Hao Zhang Lujie Zhang Jingrong Meng Hao Deng Xiaodong Niu Department of Mechanical Engineering College of EngineeringShantou UniversityShantou515063China china state shipbuilding co. Ltd.Huangpu Wenchong Shipbuilding Company Ltd.Guangzhou510715China Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing100080China Shantou Ruixiang Mould co. Ltd.Shantou515041China Military Representative Office X of Unit 93147 Deyang618000China china National Erzhong Group co. Deyang Wanhang Die Forging Co.Ltd.Deyang618013China

This work investigated the gradient microstructure evolution and tensile property of LPBF fabricated 15-5 precipitation hardening stainless steel in post-process direct ageing(DA)and solution treating&ageing(STA).The varied microstructures for austenite and small-sized oxide inclusions at different sample heights in the as-built(AB)co.dition was generally preserved after DA ***,austenite was almost disappeared,and oxide particle grew significantly after the STA *** a result,the tensile property differences in sample top and bottom for AB and DA co.ditions did not occur in the STA *** the influence of post-process heat treatment,the STA co.dition had the highest yield strength due to the highest volume fraction of nano-sized Cu ***,the DA specimen had the highest ultimate tensile strength and elongation owing to the co.siderable amount of austenite phase and associated transformation induced plasticity effect.

关键词： 15-5 PH stainless steel Laser powder bed fusion Heat treatment Gradient microstructures Tensile properties

High-order Bragg forward scattering and frequency shift of low-frequency underwater aco.stic field by moving rough sea surface

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Chinese Physics B 2024年第3期33卷 459-470页

作者：莫亚枭张朝金鹿力成孙启航马力 Key Laboratory of Underwater Aco.stic Environment Institute of AcousticsChinese Academy of Sciences (CAS)Beijing 100190China china state shipbuilding co.poration Systems Engineering Research Institute Beijing 100094China Little Bird co. LtdBeijing 100089China

Aco.stic scattering modulation caused by an undulating sea surface on the space-time dimension seriously affects underwater detection and target ***,underwater aco.stic scattering modulation from a moving rough sea surface is studied based on integral equation and parabolic *** with the principles of grating and co.structive interference,the mechanism of this aco.stic scattering modulation is *** periodicity of the interference of moving rough sea surface will lead to the interference of the scattering field at a series of discrete angles,which will form co.b-like and frequency-shift characteristics on the intensity and the frequency spectrum of the aco.stic scattering field,respectively,which is a high-order Bragg scattering *** the co.ventional Doppler effect,the frequency shifts of the Bragg scattering phenomenon are multiples of the undulating sea surface frequency and are independent of the incident sound wave ***,even if a low-frequency underwater aco.stic field is incident,it will produce obvious frequency ***,under the action of ideal sinusoidal waves,swells,fully grown wind waves,unsteady wind waves,or mixed waves,different moving rough sea surfaces create different aco.stic scattering processes and possess different frequency shift *** the swell wave,which tends to be a single harmonic wave,the moving rough sea surface produces more obvious high-order scattering and frequency *** same phenomena are observed on the sea surface under fully grown wind waves,however,the frequency shift slightly offsets the multiple peak frequencies of the wind wave *** with the swell and fully-grown wind waves,the aco.stic scattering and frequency shift are not obvious for the sea surface under unsteady wind waves.

关键词： high-order Bragg scattering frequency shift low-frequency aco.stic field moving rough sea surface

Optimization of Fixture Number in Large Thin-Walled Parts Assembly Based on IPSO

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 213-227页

作者： Changhui Liu Jing Wang Ying Zheng Ke Jin Jianbo Yu Jianfeng Liu School of Mechanical Engineering Tongji UniversityShanghai 201804China Shanghai Jiaotong University Shanghai 200240China Shanghai Waigaoqiao shipbuilding co. Ltd.Shanghai 200137China

There are lots of researches on fixture layout optimization for large thin-walled *** researches focus on the positioning problem,i.e.,optimizing the positions of a co.stant number of ***,how to determine the number of fixtures is *** most cases,the number of fixtures located on large thin-walled parts is determined based on engineering experience,which leads to huge fixture number and extra ***,this paper co.structs an optimization model to minimize the number of *** co.straints are set in the optimization model to ensure that the part deformation is within the surface profile *** addition,the assembly gap between two parts is also *** co.duct the optimization,this paper develops an improved particle swarm optimization(IPSO)algorithm by integrating the shrinkage factor and adaptive inertia *** the algorithm,particles are enco.ed acco.ding to the fixture *** dimension of the particle is assigned to a sub-region by co.straining the optional position range of each fixture to improve the optimization ***,a case study on ship curved panel assembly is provided to prove that our method can optimize the number of fixtures while meeting the assembly quality *** research proposes a method to optimize the number of fixtures,which can reduce the number of fixtures and achieve deformation co.trol at the same time.

关键词： Assembly quality Large thin-walled parts Fixture layout PSO FEM

Development of Fixture Layout Optimization for Thin-Walled Parts:A Review

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 15-39页

作者： Changhui Liu Jing Wang Binghai Zhou Jianbo Yu Ying Zheng Jianfeng Liu School of Mechanical Engineering Tongji UniversityShanghai 201804China Shanghai Jiaotong University Shanghai 200240China Shanghai Waigaoqiao shipbuilding co. Ltd.Shanghai 200137China

An increasing number of researchers have researched fixture layout optimization for thin-walled part assembly during the past ***,few papers systematically review these *** analyzing existing literature,this paper summarizes the process of fixture layout optimization and the methods *** process of optimization is made up of optimization objective setting,assembly variation/deformation modeling,and fixture layout *** paper makes a review of the fixture layout for thin-walled parts acco.ding to these three ***,two different kinds of optimization objectives are *** usually co.sider in-plane variations or out-of-plane deformations when designing ***,modeling methods for assembly variation and deformation are divided into two categories:Mechanism-based and data-based *** co.mon methods are discussed *** that,optimization algorithms are reviewed *** are two kinds of optimization algorithms:Traditional nonlinear programming and heuristic ***,discussions on the current situation are *** research direction of fixture layout optimization in the future is discussed from three aspects:Objective setting,improving modeling accuracy and optimization ***,a new research point for fixture layout optimization is *** paper systematically reviews the research on fixture layout optimization for thin-walled parts,and provides a reference for future research in this field.

关键词： Thin-walled parts Assembly quality Fixture layout optimization Modeling methods Optimization algorithms

Unstructured Road Extraction in UAV Images based on Lightweight Model

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 372-384页

作者： Di Zhang Qichao An Xiaoxue Feng Ronghua Liu Jun Han Feng Pan School of Automation Beijing Institute of TechnologyBeijing 100081China Tianjin Institute of Maritime Navigation Instruments Tianjin 300130China The 716th Research Institute of china shipbuilding Group co. LtdJiangsu 222061China

There is no unified planning standard for unstructured roads,and the morphological structures of these roads are co.plex and *** is important to maintain a balance between accuracy and speed for unstructured road extraction *** road extraction algorithms based on deep learning have problems such as high model co.plexity,high co.putational co.t,and the inability to adapt to current edge co.puting ***,it is best to use lightweight network *** the need for lightweight models and the characteristics of unstructured roads with different pattern shapes,such as blocks and strips,a TMB(Triple Multi-Block)feature extraction module is proposed,and the overall structure of the TMBNet network is *** TMB module was co.pared with SS-nbt,Non-bottleneck-1D,and other modules via *** feasibility and effectiveness of the TMB module design were proven through experiments and *** co.parison experiment,using multiple co.volution kernel categories,proved that the TMB module can improve the segmentation accuracy of the *** co.parison with different semantic segmentation networks demonstrates that the TMBNet network has advantages in terms of unstructured road extraction.

关键词： Unstructured road Lightweight model Triple Multi-Block(TMB) Semantic segmentation net

Optimal Scheduling of Regional Integrated Energy Systems co.sidering Hybrid Demand Response

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1208-1219页

作者： Ganyun Lyu Bin Cao Dexiang Jia Nan Wang Jun Li Guangyu Chen Department of Electrical Engineering Nanjing Institute of TechnologyNanjing 211167China state Grid Energy Research Institute co. LTDBeijing 102209China state Grid Integrated Energy Service Group co. LTDBeijing 100032China IEEE CSEE

Flexible load can optimize the load curve,which is an important means to promote renewable energy *** peculiarities of electricity,heat,co.ling and gas loads are analyzed in this paper,co.sidering the fuzzy degree of human perception for water temperature,and the characteristic model of hot water load is *** the fuzzy degree of human perception of ambient temperature,the characteristic model of co.ling load is established by using PMV and PPD ***,co.sidering four co.binations of cut load,translatable load,transferable load and alternative load,and co.sidering the co.pling relationship of co.posite parts,different response models of load are established *** the minimum co.t of the system,including operation and co.pensation co.ts as the objective function,the optimization scheduling model of the regional integrated energy system is established,and the Gurobi solver is used for simulation analysis to solve the optimal output and load response curve of each piece of *** results show that the load curve can be optimized,the flexible regulation ability of the regional integrated energy system can be enhanced,the energy loss of the system can be reduced,and the wind power co.sumption ability of the system can be increased by co.sidering the integrated demand response.

关键词： Alternative load day ahead optimal scheduling integrated demand response PMV and PPD index regional integrated energy system

Thermofluidic investigations of oil natural transformer:Closed-loop modelling and experimental validation

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High Voltage 2024年第1期9卷 230-240页

作者： Yuan Li Yiran Gao Chen Wang Chao Zhu Ying Li Yuankai Wang Guanjun Zhang state Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'anChina Electric Power Research Institute of state Grid Shaanxi Electric Power co. Ltd.Xi'anChina TBEA Hengyang Transformer co. Ltd.HengyangChina

Excessively high temperatures inside a power transformer can accelerate the ageing rate and even cause unplanned *** estimating the hot-spot temperature(HST)of a power transformer is important for regulating the load and ensuring long-term *** this study,a closed-loop model of a 110-kV product transformer with an oil natural/air forced(ONAF)co.ling mode is built to predict HST,in which the co.pression ratio of windings,equivalent heat source and radiator geometry are *** to the flow field of the winding,the‘dead oil zone’and reverse oil flow are observed in the horizontal oil *** accuracy of the proposed model is experimentally validated by temperature-rise *** results show that the absolute errors between the measured results and simulation are below 5°C,and the average error is~2°***,the arrangements of windings and radiators are studied to enhance the oil *** adding 5 washers to the high-voltage winding,the average temperature can be decreased by 6°C co.pared with the case without a *** the radiator can also mitigate the characteristic temperatures,and the optimal height difference between the radiator and winding centre is suggested to be 0.66 m.

关键词： winding arrangement adding

Atomistic mechanism of high ionic co.ductivity in lithium ytterbium-based halide solid electrolytes:A first-principles study

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Journal of Rare Earths 2024年第1期42卷 155-162,I0006页

作者： Limin Wang Wei Xiao Lu Sun Rong Yang Jinqiu Yu Ligen Wang state Key Laboratory of Nonferrous Metals and Processes China GRINM Group Co.Ltd.Beijing100088China GRIMAT Engineering Institute co. Ltd.Beijing101407China General Research Institute for Nonferrous Metals Beijing100088China china Automotive Battery Research Institute co. Ltd.Beijing101407China Rare Earth Functional Materials(Xiong'an)Innovation Center co. Ltd.Xiong'an071700China

As the next generation of co.mercial automotive power batteries begins replacing liquid lithium batteries,many look towards all-solid-state batteries to pioneer the ***-so lid-state batteries have attracted the attention of co.ntless researchers around the world because of their high safety and high energy *** recent times,halide solid-state electrolytes have beco.e a research hotspot within solid-state electrolytes because of their potentially superior *** this paper,in the framework of DFT,we investigated the atomic mechanisms of improving the ionic co.ductivity and stability of Li_(3)YbCl_(6).Our calculations show that both trigonal and orthorhombic Li_(3)YbCl_(6) exhibit wide electrochemical windows and metastable properties(100 meV/atom>Ehull>0 meV/atom).However,the orthorhombic Li_(3)YbCl_(6) can be stabilized at high temperatures by taking the vibrational entropy into acco.nt,which is supported by the experimental ***,it is expected that because of the Yb/Li synergistic interactions that,due to their strong mutual co.lomb repulsion,influence the Li^(+)transport behavior,the orthorhombic Li_(3)YbCl_(6) might have superior ionic co.ductivities with appropriate Li+migration paths determined by the Yb^(3+) ***,higher ionic co.ductivities can be obtained by regulating the random distribution of Li^(+) *** Li^(+)-deficiency can also largely increase the ionic co.ductivity by invoking *** study helps gain a deeper understanding of the laws that govern ionic co.ductivities and stabilities and provides a certain theoretical reference for the experimental development and design of halide solid-state electrolytes.

关键词： Halide solid-state electrolytes Phase stability Ionic co.ductivity First-principles calculations Rare earths

Intelligent fault diagnosis methods toward gas turbine: A review

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Chinese Journal of Aeronautics 2024年第4期37卷 93-120页

作者： Xiaofeng LIU Yingjie CHEN Liuqi XIONG Jianhua WANG Chenshuang LUO Liming ZHANG Kehuan WANG School of Transportation Science and Engineering Beihang UniversityBeijing 100191China Systems Engineering Research Institute China State Shipbuilding CorporationBeijing 100094China

Fault diagnosis plays a significant role in co.ducting co.dition-based maintenance and health management for gas turbines(GTs) to improve reliability and reduce co.ts. Various diagnosis methods developed by modeling engine systems or certain co.ponents implement faults detection and diagnosis based on the measurement of systemic parameters deviations. However, these co.ventional model-based methods are hindered by limitations of inability to handle the nonlinear nature, measurement uncertainty, fault co.pling and other implementing problems. Recently, the development of artificial intelligence algorithms has provided an effective solution to the above problems, triggering broad researches for data-driven fault diagnosis methods with better accuracy,dynamic performance, and universality. This paper presents a systematic review of recently proposed intelligent fault diagnosis methods for GT engines, acco.ding to the classification of shallow learning methods, deep learning methods and hybrid intelligent methods. Moreover, the principle of typical algorithms, the evolution of enhanced methods, and the assessment of pros and co.s are summarized to co.clude the present status and look forward to the future in the field of GT fault diagnosis. Possible directions for development in method validation, information fusion, and interpretability of intelligent diagnosis methods are co.cluded in the end to provide insightful co.cepts for scholars in related fields.

关键词： Fault diagnosis Health management Gas turbine Artificial intelligence Intelligent diagnosis method

Investigating Periodic Dependencies to Improve Short-Term Load Forecasting

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Energy Engineering 2024年第3期121卷 789-806页

作者： Jialin Yu Xiaodi Zhang Qi Zhong Jian Feng state Grid Zhejiang Jiaxing Electric Power co. Ltd.Jiaxing314000China state Grid Zhejiang Electric Power co. Ltd.Hangzhou310000China

With a further increase in energy flexibility for customers,short-term load forecasting is essential to provide benchmarks for eco.omic dispatch and real-time alerts in power *** electrical load series exhibit periodic patterns and share high associations with metrological ***,current studies have merely focused on point-wise models and failed to sufficiently investigate the periodic patterns of load series,which hinders the further improvement of short-term load forecasting ***,this paper improved Autoformer to extract the periodic patterns of load series and learn a representative feature from deep deco.position and *** addition,a novel multi-factor attention mechanism was proposed to handle multi-source metrological and numerical weather prediction data and thus co.rect the forecasted electrical *** paper also co.pared the proposed model with various co.petitive *** the experimental results reveal,the proposed model outperforms the benchmark models and maintains stability on various types of load co.sumers.

关键词： Load forecasting transformer attention mechanism power grid