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Evaluation on cutting performance of novel PDC cutter for pipe jacking machine

Underground Space 2024年第1期14卷 34-52页

作者： Long-Chuan Deng Yi-Xiang Yuan Xiao-Zhao Li qian-wei zhuang Chi Zhang Yi-wei Chen School of Earth Sciences and Engineering Nanjing UniversityNanjingJiangsu 210023China Shanghai Tunnel Engineering Co.Ltd. Shanghai 200232China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhouJiangsu 221116China School of Mechanics and Engineering Science Shanghai UniversityShanghai 200444China

It is inevitable to cut reinforced concrete(RC)appeared in cross passage of city metro by cutting tools when constructing in densely populated *** previous cutters employed to cut RC are insufficient and easily damaged,so a new polycrystalline diamond compact(PDC)cutter is used to solve this *** on the theoretical analysis of cutting mechanism,both circular and tapered PDC cutters with cutting edge angle of 90and negative front rack angle of 10are used to cut *** peeling and breaking patterns of cutting concrete are proposed,the nodular and grainy chips are the preferred modes in cutting steel *** LS-DYNA is employed to investigate the cutting performance in *** simulation results show that the average and peak cutting forces increase with the growth of penetration depth,cutting speed,and roundness,and subsequently the recommended penetration depth less than 1.2 mm is obtained to cut RC due to the existence of steel ***,the linear cutting platform is adopted to investigate the force ability and damage state of PDC *** is concluded that the cutting force increases abruptly and fluctuates heavily when cutting the coarse *** patterns occurred in both numerical and experimental results are generally ***,the steel bar is pulled out and the PDC cutter is damaged at the penetration depth of 0.8 mm,while a good cut occurs at the penetration depth of 0.3 *** tapered PDC cutter with a relatively low cutting force is prone to be broken compared with circular PDC *** is suggested that the circular PDC cutter at the penetration depth of 0.3 mm should be used to cut RC in practical engineering.

关键词： PDC cutter RC Pipe jacking machine Linear cutting tests Damage and wear LS-DYNA

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Aerial target threat assessment based on gated recurrent unit and self-attention mechanism

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Journal of Systems Engineering and Electronics 2024年第2期35卷 361-373页

作者： CHEN Chen QUAN wei SHAO zhuang School of Automation Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing 100081China

Aerial threat assessment is a crucial link in modern air combat, whose result counts a great deal for commanders to make decisions. With the consideration that the existing threat assessment methods have difficulties in dealing with high dimensional time series target data, a threat assessment method based on self-attention mechanism and gated recurrent unit(SAGRU) is proposed. Firstly, a threat feature system including air combat situations and capability features is established. Moreover, a data augmentation process based on fractional Fourier transform(FRFT) is applied to extract more valuable information from time series situation features. Furthermore, aiming to capture key characteristics of battlefield evolution, a bidirectional GRU and SA mechanisms are designed for enhanced ***, after the concatenation of the processed air combat situation and capability features, the target threat level will be predicted by fully connected neural layers and the softmax classifier. Finally, in order to validate this model, an air combat dataset generated by a combat simulation system is introduced for model training and testing. The comparison experiments show the proposed model has structural rationality and can perform threat assessment faster and more accurately than the other existing models based on deep learning.

关键词： target threat assessment gated recurrent unit(GRU) self-attention(SA) fractional Fourier transform(FRFT)

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Therapeutic advances in atrial fibrillation based on animal models

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第2期25卷 135-152页

作者： qian GONG Xuan LE Pengcheng YU Lenan zhuang Institute of Genetics and Reproduction College of Animal SciencesZhejiang UniversityHangzhou310058China Key Laboratory of Cardiovascular Intervention and Regenerative Medicine of Zhejiang Province Department of CardiologySir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou310016China

Atrial fibrillation(AF)is the most prevalent sustained cardiac arrhythmia among humans,with its incidence increasing significantly with *** the high frequency of AF in clinical practice,its etiology and management remain *** develop effective treatment strategies,it is imperative to comprehend the underlying mechanisms of AF;therefore,the establishment of animal models of AF is vital to explore its *** spontaneous AF is rare in most animal species,several large animal models,particularly those of pigs,dogs,and horses,have proven as invaluable in recent years in advancing our knowledge of AF pathogenesis and developing novel therapeutic *** review aims to provide a comprehensive discussion of various animal models of AF,with an emphasis on the unique features of each model and its utility in AF research and *** data summarized in this review provide valuable insights into the mechanisms of AF and can be used to evaluate the efficacy and safety of novel therapeutic interventions.

关键词： Atrial fibrillation Animal model Therapeutic

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Investigation of Adhesive Perception Based on Friction and Brain Activation

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Journal of Bionic Engineering 2024年第4期21卷 1862-1877页

作者： Xingxing Fang wei Tang Shousheng Zhang Tengfei zhuang School of Mechatronic Engineering China University of Mining and TechnologyXuzhou221116JiangsuChina

The enhancement of adhesive perception is crucial to maintaining a stable and comfortable grip of the skin-touch *** study the tactile perception of adhesive surfaces,subjective evaluation,skin friction and vibrations,and neurophysiological response of the brain activity were investigated *** materials,which are commonly used for bionic materials and skin-touch products,were chosen for the tactile *** results showed that with the increasing of surface adhesion,the dominant friction transferred from a combination of adhesive friction and deformation friction to adhesive *** friction coefficient and vibration amplitude had strong correlations with the perceived adhesion of *** parietal lobe and occipital lobe were involved in adhesive perceptions,and the area and intensity of brain activation increased with the increasing surface *** with larger adhesion tended to excite a high P300 amplitude and short latency,indicating that the judgment was faster and that more attentional resources were involved in adhesive ***,the electroencephalograph signals of the adhesive perception were simulated by the neural mass *** demonstrated that the excitability and intensity of brain activity,and the connectivity strength between two neural masses increased with the increasing surface *** study is meaningful to understand the role of surface adhesion in tactile friction and the cognitive mechanism in adhesive perception to improve the tactile experience of adhesive materials.

关键词： Surface adhesion Tactile perception Friction Brain activation Neural mass model

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A historical review of hybrid rice breeding

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Journal of Integrative Plant Biology 2024年第3期66卷 532-545页

作者： Xiaoming Zheng Fei wei Cheng Cheng qian qian State Key Laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China Yazhouwan National Laboratory Sanya City 572024China

The development of germplasm resources and advances in breeding methods have led to steady increases in yield and quality of rice (Oryza sativa L.). Three milestones in the recent history of rice breeding have contributed to these increases: dwarf rice breeding, hybrid rice breeding, and super rice breeding. On the 50th anniversary of the success of three-line hybrid rice,we highlight important scientific discoveries in rice breeding that were made by Chinese scientists and summarize the broader history of the field. We discuss the strategies that could be used in the future to optimize rice breeding further in the hope that China will continue to play a leading role in international rice breeding.

关键词： Chinese experience dwarf breeding hybrid rice breeding super rice breeding

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A Deep Mantle Source for the Late Neoarchean Metamorphosed Basalts in Eastern Hebei,North China Craton:Insights from Whole-Rock Geochemistry and Sm-Nd Isotopes,and Zircon U-Pb-Hf Isotopes

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Journal of Earth Science 2024年第1期35卷 29-40页

作者： zhuang Li Chunjing wei Chuan Yang Xi Zhang College of Geosciences China University of PetroleumBeijing 102249China MOE Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing 100871China China Transport Telecommunications and Information Center Beijing 100011China

The basalts within the greenstone belt worldwide serve as an ideal target to decipher the nature of Archean mantle sources and further to extend the understanding of the early stages of Earth's *** provide important insights into the issues,we carried out a detailed investigation of whole-rock geochemistry and Sm-Nd isotopes,and zircon U-Pb-Hf isotopes for the Late Neoarchean metamorphosed basalts in eastern Hebei,North China Craton.U-Pb isotopic dating using the LA-ICPMS on zircons reveals that the basalts in eastern Hebei erupted at ca.2.48-2.51 Ga and subsequently experienced multiple regional metamorphic events at 2477 and 1798 Ma,*** metamorphosed basalts are featured by low SiO_(2),MgO,K_(2)O+Na_(2)O,and high Fe O contents,endowed with the subalkaline and high-Fe tholeiitic *** radiogenic initial Nd and Hf isotope values and correlations among V,Ni and Cr contents strongly imply that the basalts experienced significant clinopyroxene and olivine fractionation and minor crustal contamination during magma *** are also characterized by the relatively low total REE contents and exhibit significant depletions to moderate enrichments in the LREE contents,indicating the derivation from a deep mantle source in an Archean proto-mantle plume setting.

关键词： zircon U-Pb-Hf isotopes geochemistry Late Neoarchean basaltic magmatism North China Craton Archean proto-mantle plume

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Progress on Bionic Textured Cutting Tools:A Review and Prospects

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Journal of Bionic Engineering 2024年第1期21卷 19-55页

作者： Hong wei Guangjun Chen zhuang Chen Zhiwei Yu Jiashuai Huang Tianjin Key Laboratory of High Speed Cutting and Precision Processing Tianjin 300222China School of Mechanical Engineering Tianjin University of Technology and EducationTianjin 300222China

Cutting tools are known as the“productivity”of the manufacturing industry,which affects the production efficiency and quality of the workpiece,and has become the focus of research and attention in academia and ***,traditional cutting tools often suffer from adhesion or wear during the cutting process,which considerably reduces the cutting efficiency and service life of the tools,and makes it difficult to meet current production *** solve the above problems,scholars have introduced bionics into the tool’s design,applying the microscopic structure of the biological surface to the tool surface to alleviate the tool’s *** paper mainly summarizes the research progress of bionic textured cutting ***,categorize whether the bionic texture design is inspired by a single organism or multiple ***,it is discussed that the non-smooth surface of the biological surface has five characteristics:hydrophilic lubricity,wear resistance,drag reduction and hydrophobicity,anti-adhesion,and arrangement,and the non-smooth structure of these different characteristics are applied to the surface of the tool is designed with bionic ***,the cutting performance of bionic textured cutting tools is *** anti-friction and wear-resisting mechanism of bionic textured cutting tools is ***,some pending problems and perspectives have been proposed to provide new inspirations for the design of bionic textured cutting tools.

关键词： Bionic textured cutting tools Biological microstructure characteristics Cutting performance Anti-friction and wear-resisting mechanism

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Optimization Mechanism of Mechanical Properties of Basalt Fiber-Epoxy Resin Composites by Interfacially Enriched Distribution of Nano-Starch Crystals

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 289-296页

作者： Yanpeng wei Jiale Zhao Jian zhuang Peng Zhang Zhiwu Han College of Biological and Agricultural Engineering Jilin UniversityChangchun 130025China Key Laboratory of Bionics Engineering Ministry of EducationJilin UniversityChangchun 130025China weichai Lovol Heavy Industry Co. LTDWeifang 261031China

Fibre reinforced polymer composites have become a new generation of structural materials due to their unique advantages such as high specific strength,designability,good dimensional stability and ease of large-area monolithic ***,the problem of interfacial bonding between the resin matrix and the fibres limits the direct use of reinforcing fibres and has become a central difficulty in the development of basalt fibre-epoxy *** paper proposes a solution for enhancing the strength of the fibre-resin interface using maize starch nanocrystals,which are highly yield and ***,in this paper,corn starch nanocrystals(SNC)were prepared by hydrolysis,and were deposited on the surface of basalt fibers by electrostatic *** that,in order to maximize the modification effect of nano-starch crystals on the interface,the basalt fiber-epoxy resin composite samples were prepared by mixing in a pressureless molding *** test results shown that the addition of basalt fibers alone led to a reduction in the strength of the *** of 0.1 wt%SNC on the surface of basalt fibers can make the strength consistent with pure epoxy *** the adsorption amount of SNC reached 0.5 wt%,the tensile strength of the samples was 23.7%higher than that of pure epoxy *** is due to the formation of ether bond homopolymers between the SNC at the fibre-epoxy interface and the epoxy resin,which distorts the originally smooth interface,leading to increased stress concentration and the development of *** enhances the binding of basalt *** conclusions of this paper can provide an effective,simple,low-cost and non-polluting method of interfacial enhancement modification.

关键词： Basalt fibres Epoxy resin Fibre reinforced composites Starch nanocrystals Eco-friendly

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Glial progenitor heterogeneity and plasticity in the adult spinal cord

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Neural Regeneration Research 2024年第12期19卷 2567-2568页

作者： Haichao wei Jia qian Wu Department of Neurosurgery McGovern Medical SchoolThe University of Texas Health Science Center at HoustonHoustonTXUSA Center for Stem Cell and Regenerative Medicine UT Brown Foundation Institute of Molecular MedicineHoustonTXUSA MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences HoustonTXUSA

Glial progenitor cells were reported to have the capacity to generate various types of cells in both the central nervous system(CNS)and peripheral nervous *** progenitor cells can respond to diverse environmental signals and transform into distinct populations,each serving specific ***,the adult spinal cord hosts various populations of glial progenitors,a region integral to the central nervous *** development,glial progenitors express glial fibrillary acidic protein(GFAP;Dimou and Gotz,2014).However,the specific identities of GFAP-expressing progenitors in the adult spinal cord were not thoroughly investigated.

关键词： functions plasticity thoroughly

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Novel Adaptive Memory Event-Triggered-Based Fuzzy Robust Control for Nonlinear Networked Systems via the Differential Evolution Algorithm

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1836-1848页

作者： wei qian Yanmin Wu Bo Shen School of Electrical Engineering and Automation Henan Polytechnic UniversityJiaozuo 454000China College of Information Science and Technology Donghua UniversityShanghai 201620China

This article mainly investigates the fuzzy optimization robust control issue for nonlinear networked systems characterized by the interval type-2(IT2)fuzzy technique under a differential evolution *** provide a more reasonable utilization of the constrained communication channel,a novel adaptive memory event-triggered(AMET)mechanism is developed,where two event-triggered thresholds can be dynamically adjusted in the light of the current system information and the transmitted historical *** conditions with less conservative design of the fuzzy imperfect premise matching(IPM)controller are presented by introducing the Wirtinger-based integral inequality,the information of membership functions(MFs)and slack ***,under the IPM policy,a new MFs intelligent optimization technique that takes advantage of the differential evolution algorithm is first provided for IT2 TakagiSugeno(T-S)fuzzy systems to update the fuzzy controller MFs in real-time and achieve a better system control ***,simulation results demonstrate that the proposed control scheme can obtain better system performance in the case of using fewer communication resources.

关键词： Adaptive memory event-triggered(AMET) differential evolution algorithm fuzzy optimization robust control interval type-2(IT2)fuzzy technique.

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