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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 357-381页

作者： Yakun ZHANG Guofang GONG Huayong YANG Jianbin li liujie JING State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China China Railway Engineering Equipment Group Co. Lid.Zhengzhou 450016China Maha Fluid Power Research Center Purdue UniversityWest LafayetteIN 47905USA

Advances in intelligent shield machines reflect an evolving trend from traditional tunnel boring machines(TBMs)to tunnel boring robots(TBRs).This shift aims to address the challenges encountered by the conventional shield machine industry arising from construction environment and manual *** study presents a systematic review of intelligent shield machine technology,with a particular emphasis on its smart ***,the definition,meaning,contents,and development modes of intelligent shield machines are *** development status of the intelligent shield machine and its smart operation are then *** analyzing the operation process of the shield machine,an autonomous operation framework considering both stand-alone and fleet levels is *** and recommendations are given for achieving autonomous *** study offers insights into the essence and developmental framework of intelligent shield machines to propel the advancement of this technology.

关键词： Intelligent shield machine Tunnel boring machine(TBM) Tunnel boring robot(TBR) Self-driving Autonomous control Shield machine

A multi-scale framework for life reduction assessment of turbine blade caused by microstructural degradation

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Chinese Journal of Aeronautics 2024年第1期37卷 186-200页

作者： Xiaoguang YANG Menglei WANG Duoqi SHI Zhenlei li Yongsheng FAN School of Energy and Power Engineering Beihang UniversityBeijing 102206China Research Institute of Aero-Engine Beihang UniversityBeijing 102206China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 102206China

The prolonged thermal exposure with centrifugal load results in microstructural degradation,which ultimately leads to a reduction in the fatigue and creep resistance of the turbine *** present work proposes a multi-scale framework to estimate the life reduction of turbine blades,which combines a microstructural degradation model,a two-phase constitutive model,and a microstructure-dependent fatigue and creep life reduction *** framework with multi-scale models is validated by a Single Crystal(SC)Ni-based superalloy at the microstructural length-scale and is then applied to calculate the microstructural degradation and the fatigue and creep life reduction of turbine blades under two specific service *** simulation results and quantitative analysis show that the microstructural degradation and fatigue and creep life reduction of the turbine blade are heavily influenced by the variations in the proportion of the intermediate state,namely,the maximum rotor speed status,in the two specific service *** intermediate state accelerates the microstructural degradation and leads to a reduction of the life,especially the effective fatigue life reserve due to the higher temperature and rotational speed than that of the 93%maximum rotor speed status marked as the reference *** proposed multi-scale framework provides a capable approach to analyze the reduction of the fatigue and creep life for turbine blade induced by microstructural degradation,which can assist to determine a reasonable Time Between Overhaul(TBO)of the engine.

关键词： Creep Fatigue life reduction Microstructural degradation Multi-scale modeling Turbine blades

Dredged marine soil stabilization using magnesia cement augmented with biochar/slag

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1000-1017页

作者： Chikezie Chimere Onyekwena Qi li Yong Wang Ishrat Hameed Alvi Wentao li Yunlu Hou Xianwei Zhang Min Zhang State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China School of Civil Engineering Architecture and EnvironmentHubei University of TechnologyWuhan430068China School of Urban Construction Wuhan University of Science and TechnologyWuhan430065China School of Civil Engineering and Archtitecture Henan UniversityKaifeng475001China

Dredged marine soils(DMS)have poor engineering properties,which limit their usage in construction *** research examines the application of reactive magnesia(rMgO)containing supplementary cementitious materials(SCMs)to stabilize DMS under ambient and carbon dioxide(CO_(2))curing *** proprietary experimental tests were conducted to investigate the stabilized ***,the carbonation-induced mineralogical,thermal,and microstructural properties change of the samples were *** findings show that the compressive strength of the stabilized DMS fulfilled the 7-d requirement(0.7-2.1 MPa)for pavement and building *** rMgO with SCMs such as biochar or ground granulated blast-furnace slag(GGBS)altered the engineering properties and particle packing of the stabilized soils,thus influencing their *** increased the porosity of the samples,facilitating higher CO_(2) uptake and improved ductility,while GGBS decreased porosity and increased the dry density of the samples,resulting in higher *** addition of SCMs also enhanced the water retention capacity and modified the pH of the *** analysis revealed that the hydrated magnesium carbonates precipitated in the carbonated samples provided better cementation effects than brucite formed during rMgO ***,incorporating SCMs reduced the overall global warming potential and energy demand of the rMgO-based *** biochar mixes demonstrated lower toxicity and energy ***,the rMgO and biochar blend can serve as an environmentally friendly additive for soft soil stabilization and permanent fixation of significant amounts of CO_(2) in soils through mineral carbonation,potentially reducing environmental pollution while meeting urbanization needs.

关键词： Dredged marine soil CO_(2)uptake Reactive magnesia Biochar Ground granulated blast-furnace slag

Distributed Robust Optimal Dispatch of Regional Integrated Energy Systems Based on ADMM Algorithm with Adaptive Step Size

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 852-862页

作者： Zhoujun Ma Yizhou Zhou Yuping Zheng li Yang Zhinong Wei the College of Energy and Electrical Engineering Hohai UniversityNanjing 211100China State Grid Jiangsu Electric Power Co. Ltd.Nanjing 210019China State Key Laboratory ofSmart Grid Protection and Control NARI Group CorporationNanjing 211106China

This paper proposes a distributed robust optimal dispatch model to enhance information security and interaction among the operators in the regional integrated energy system(RIES).Our model regards the distribution network and each energy hub(EH)as independent operators and employs robust optimization to improve operational security caused by wind and photovoltaic(PV)power output uncertainties,with only deterministic information exchanged across *** paper also adopts the alternating direction method of multipliers(ADMM)algorithm to facilitate secure information interaction among multiple RIES operators,maximizing the benefit for each ***,the traditional ADMM algorithm with fixed step size is modified to be adaptive,addressing issues of redundant interactions caused by suboptimal initial step size settings.A case study validates the effectiveness of the proposed model,demonstrating the superiority of the ADMM algorithm with adaptive step size and the economic benefits of the distributed robust optimal dispatch model over the distributed stochastic optimal dispatch model.

关键词： Regional integrated energy system(RIES) distributed optimization robust optimization operation security energy hub(EH)

Time-domain dynamic constitutive model suitable for mucky soil site seismic response

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 1-13页

作者： Dong Qing Chen Su Jin liguo Zhou Zhenghua li Xiaojun Architectural Engineering Institute Huaiyin Institute of TechnologyHuai’an 223600China Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100020China Institute of Geophysics China Earthquake AdministrationBeijing 100089China College of Transportation Science and Engineering Nanjing Tech UniversityNanjing 211816China

Soil nonlinear behavior displays noticeable effects on the site seismic *** study proposes a new functional expression of the skeleton curve to replace the hyperbolic skeleton *** integrating shear modulus and combining the dynamic skeleton curve and the damping degradation coefficient,the constitutive equation of the logarithmic dynamic skeleton can be obtained,which considers the damping effect in a soil dynamics *** on the finite difference method and the multi-transmitting boundary condition,a 1D site seismic response analysis program called Soilresp1D has been developed herein and used to analyze the time-domain seismic response in three types of *** the same time,this study also provides numerical simulation results based on the hyperbolic constitutive model and the equivalent linear *** results verify the rationality of the new soil dynamic constitutive *** can analyze the mucky soil site nonlinear seismic response,reflecting the deformation characteristics and damping effect of the silty *** hysteresis loop area is more extensive,and the residual strain is evident.

关键词： seismic response time-domain dynamic constitutive model logarithmic dynamic skeleton dampening effect mucky soil

Strengthened and toughened SiHfBCN-based hightemperature resistant adhesive with SiC NWs

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Chinese Journal of Aeronautics 2024年第7期37卷 539-549页

作者： Xingang LUAN Xiyue ZHU Xichao DONG Min li Laifei CHENG Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China

To further improve the performance of binders,a SiHfBCN-based high-temperature resistant adhesive was successfully synthesized by Polymer-Derived Ceramics(PDC)route using TiB2,Polysiloxane(PSO)and short SiC nanowires as *** effect of short SiC nanowires on the adhesive strength at room temperature and high temperature,as well as the reinforcing mechanism was *** with the adhesive without SiC nanowires,after curing(at 170℃)and pyrolysis(at 1000℃)in air,the appropriate adding of SiC nanowires upgrades the room temperature and high temperature(at 1000℃ in air)adhesive strength to(12.50±0.67)MPa(up by about 32%)and(13.11±0.79)MPa(up by about 106%),***,under the synergistic impact of the nanowire bridging,nanowire breaking,nanowire drawing and crack deflection,the optimized adhesive exhibits multi-stage fracture,causing the increscent fracture displacement.

关键词： High-temperature resistant adhesive SiHfBCN SiC NWs Strengthening Toughening

Minimal Legendrian surfaces in the tangent sphere bundle of R3

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Science China Mathematics 2024年第11期67卷 2607-2628页

作者： Mingyan li Guofang Wang School of Mathematical Sciences Ocean University of China Mathematisches Institut Albert-Ludwigs-Universit?t Freiburg

In this paper,we study minimal Legendrian surfaces Σ immersed in the tangent sphere bundle *** classify(1) totally geodesic Legendrian surfaces,(2) closed minimal Legendrian surfaces of genus smaller than or equal to 1 and complete minimal Legendrian surfaces with the non-negative Gauss curvature,and(3) complete stable minimal Legendrian surfaces.

关键词： 53C24 53C42 classification Legendrian surface stable minimal surface tangent sphere bundle

Effects of content and particle size of TiH2 powders on the energy output rules of RDX composite explosives

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Defence Technology（防务技术） 2024年第2期32卷 297-308页

作者： Hao Wang Yangfan Cheng Shoujun Zhu Zihan li Zhaowu Shen School of Chemical Engineering Anhui University of Science and TechnologyHuainan 232001China Anhui Engineering Laboratory of Explosive Materials and Technology Anhui University of Science and TechnologyHuainan 232001China School of Engineering Science University of Science and Technology of ChinaHefei 230027China

In order to improve the detonation characteristics of RDX,a RDX-based composite explosive with TiH_(2)powders was *** effects of content and particle size of TiH_(2)powders on thermal safety,shock wave parameters and thermal damage effects of RDX-based composite explosive were studied with the C80 microcalorimeter,air blast experiment system and colorimetric thermometry *** results showed that TiH_(2)powders could enhance the thermal stability of RDX-based composite explosive and increase its ultimate decomposition *** content and particle size of TiH_(2)powders also had significant effects on the thermal safety,detonation velocity,shock wave parameters,fireball temperature and duration of RDX-based composite ***,the differences of TiH_(2)and Ti powders on the detonation energy output rules of RDX-based composite explosives were also compared,showing that TiH_(2)powders had better influences on improving the explosion power and thermal damage effect of RDX-based composite explosives than Ti powders,for the participation of free H_(2)released by TiH_(2)powders in the detonation ***_(2)powders have important research values as a novel energetic additive in the field of military composite explosives.

关键词： RDX Hydrogen storage alloy Air blast After-burn reaction Colorimetric thermometry

基于膏脂理论和脂代谢重编程探讨多囊卵巢综合征病机

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中国中西医结合杂志 2024年第1期44卷 101-106页

作者：李婧赵珊珊潘紫萌孙畅徐珂匡洪影黑龙江中医药大学研究生院哈尔滨150040 北京中医医院顺义医院妇产科北京101300 黑龙江中医药大学附属第一医院妇二科哈尔滨150040

多囊卵巢综合征(PCOS)是一种复杂的多因素内分泌代谢紊乱性疾病,病因涉及遗传因素和生活方式的相互作用,其中脂代谢重编程机制可能是PCOS病机中的中心环节。在中医古籍中阐述的相关膏脂理论表明膏脂失衡易诱发肥人不孕。故笔者基于膏脂... 详细信息

多囊卵巢综合征(PCOS)是一种复杂的多因素内分泌代谢紊乱性疾病,病因涉及遗传因素和生活方式的相互作用,其中脂代谢重编程机制可能是PCOS病机中的中心环节。在中医古籍中阐述的相关膏脂理论表明膏脂失衡易诱发肥人不孕。故笔者基于膏脂理论和脂代谢重编程机制,探讨膏脂失衡与脂代谢重编程异常对PCOS的作用与影响,为临床诊疗PCOS提供新思路。

关键词：多囊卵巢综合征膏脂理论脂代谢重编程脂质代谢中西医结合

Robust-augmentation nonlinear dynamic inversion control of over-actuated coaxial high-speed helicopter in transition mode

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Chinese Journal of Aeronautics 2024年第8期37卷 404-420页

作者： Yuqing QIU Yan li Jinxi LANG Yuxian liU Zhong WANG School of Automation Northwestern Polytechnical UniversityXi’an 710129China

As the elevator and rudder can be used actively for control,in addition to the rotors,Coaxial High-speed Helicopters(CHHs)have the problems of control redundancy and changing control authority in the transition *** paper presents a robust-augmentation transitioning flight control design for a CHH under the adverse conditions of parametric uncertainties and external ***,based on control characteristic analysis,an Adaptive Filtered Nonlinear Dynamic Inversion(AFNDI)controller is proposed for the angular rate to handle the effect of unknown unstructured uncertainties and external *** analysis proves that the presented angular rate controller can guarantee steady-state and transient ***,the attitude angle and velocity controllers are also ***,an Incremental-based Nonlinear Prioritizing Control Allocation(INPCA)method is designed to take into account control surface transition and changing control authority,which efficiently distributes the required moments between coaxial rotors and aero-surfaces,and avoids the control reversal problem of the yaw *** the proposed control architecture,the low-pass filter is introduced to alleviate the adverse influence of time delay and measurement ***,the effectiveness of the proposed controller is demonstrated through nonlinear numerical simulations,and is compared with existing *** results show that the proposed control law can improve both capabilities of disturbance rejection and fast response,and works satisfactorily for the CHH transitioning control characteristic.

关键词： Coaxial high-speed helicopter Transition mode Attitude control Control allocation Robust adaptive control