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Review of bio-inspired image sensors for efficient machine vision

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Advanced Photonics 2024年第2期6卷 7-19页

作者： Wenhao Tang Qing Yang hang xu Yiyu Guo Jiqiang Zhang Chunfang Ouyang Leixin Meng xu Liu Zhejiang Laboratory Research Center for Frontier Fundamental StudiesHangzhouChina Zhejiang University College of Optical Science and EngineeringState Key Laboratory of Extreme Photonics and InstrumentationHangzhouChina ZJU-hangzhou Global Scientific and Technological Innovation Center HangzhouChina Shanghai Jiao Tong University Chip Hub for Integrated Photonics Xplore(CHIPX)WuxiChina

With the rapid development of sensor networks,machine vision faces the problem of storing and computing massive data.The human visual system has a very efficient information sense and computation ability,which has enlightening significance for solving the above problems in machine vision.This review aims to comprehensively summarize the latest advances in bio-inspired image sensors that can be used to improve machine-vision processing efficiency.After briefly introducing the research background,the relevant mechanisms of visual information processing in human visual systems are briefly discussed,including layerby-layer processing,sparse coding,and neural adaptation.Subsequently,the cases and performance of image sensors corresponding to various bio-inspired mechanisms are introduced.Finally,the challenges and perspectives of implementing bio-inspired image sensors for efficient machine vision are discussed.

关键词： bio-inspired image sensor machine vision layer-by-layer processing sparse coding neural adaptation

Seabed structures and foundations related to deep-sea resource development:A review based on design and research

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Deep Underground Science and Engineering 2024年第2期3卷 131-148页

作者： Shengjie Rui Haojie Zhang hang xu Xing Zha Mengtao xu Kanmin Shen Key Laboratory of Offshore Geotechnics and Material of Zhejiang Province College of Civil Engineering and ArchitectureZhejiang UniversityHangzhouChina Advanced Modelling Offshore EnergyNorwegian Geotechnical InstituteOsloNorway Geotechnical Technology Center(Overseas Engineering Center) PowerChina Huadong Engineering Corporation LimitedHangzhouChina

The deep‐sea ground contains a huge amount of energy and mineral resources,for example,oil,gas,and minerals.Various infrastructures such as floating structures,seabed structures,and foundations have been developed to exploit these resources.The seabed structures and foundations can be mainly classified into three types:subsea production structures,offshore pipelines,and anchors.This study reviewed the development,installation,and operation of these infrastructures,including their structures,design,installation,marine environment loads,and applications.On this basis,the research gaps and further research directions were explored through this literature review.First,different floating structures were briefly analyzed and reviewed to introduce the design requirements of the seabed structures and foundations.Second,the subsea production structures,including subsea manifolds and their foundations,were reviewed and discussed.Third,the basic characteristics and design methods of deep‐sea pipelines,including subsea pipelines and risers,were analyzed and reviewed.Finally,the installation and bearing capacity of deep‐sea subsea anchors and seabed trench influence on the anchor were reviewed.Through the review,it was found that marine environment conditions are the key inputs for any offshore structure design.The fabrication,installation,and operation of infrastructures should carefully consider the marine loads and geological conditions.Different structures have their own mechanical problems.The fatigue and stability of pipelines mainly depend on the soil‐structure interaction.Anchor selection should consider soil types and possible trench formation.These focuses and research gaps can provide a helpful guide on further research,installation,and operation of deep‐sea structures and foundations.

关键词： anchors floating structures pipelines risers subsea foundations

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Highly selective and eco-friendly dihydroisoquinoline synthesis via Cu/Co synergistic catalysis in Cu NPs@MOFs catalyst under mild conditions

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Science China Chemistry 2024年第5期67卷 1561-1568页

作者： Peng-Fei Guo Ze-Long Liang Yue-E Jiao hang xu Bin Zhao Key Laboratory of Advanced Energy Material Chemistry Renewable Energy Conversion and Storage CenterDepartment of ChemistryNankai UniversityTianjin 300071China

3,4-Dihydroisoquinoline(DHIQ)is an important precursor used in the production of drugs for treating cancer,HIV,Alzheimer's disease,etc.Major studies on DHIQ synthesis show low catalytic selectivity due to the susceptible over-oxidation feedstock of1,2,3,4-tetrahydroisoquinoline(THIQ),which often requires alkali co-catalysts.Therefore,it is desirable yet challenging to explore a highly selective and efficient oxydehydrogenation capacity for DHIQ synthesis under eco-friendly reaction conditions.Herein,a novel framework 1 was synthesized,exhibiting 1D channels with the size of 4.6 A×9.6 A and high solvent/p H/thermal stability.A stable framework allows it to encapsulate Cu nanoparticles(NPs)to form Cu NPs@1-x(x=1,2,3,and 4)with varying loading amounts of Cu NPs at 2.0 wt%,3.0 wt%,4.0 wt%,and 6.0 wt%,respectively.Cu NPs@1-3 could selectively catalyze the reaction from THIQ to DHIQ with a high selectivity of 98%and a recorded turnover frequency(TOF)of 22.1 h-1under eco-friendly mild conditions.The corresponding catalytic activity can maintain at least five recyclings and can be further applied to gram-scale experiments.Additionally,the efficient preparation of DHIQ catalyzed by Cu NPs@1-3 could be realized even under air conditions.Importantly,the anticancer molecule precursor synthesis of 6,7-dimethoxy-3,4-dihydroisoquinoline was also selectively catalyzed by Cu NPs@1-3.Mechanism investigations revealed that high catalytic performance can be attributed to the stable framework and the synergistic catalytic effect of the loaded Cu NPs and Co metal centers.More importantly,this work represents the first example of MOF catalysts for selectively thermo-catalytic DHIQ synthesis and demonstrates a simple approach to obtain efficient catalysts for selective oxydehydrogenation in the production of unsaturated compounds.

关键词： metal-organic frameworks Cu NPs@MOFs 3 4-dihydroisoquinoline selective oxydehydrogenation synergistic catalysis

On the analytic and geometric aspects of obstruction flatness

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Acta Mathematica Sinica,English Series 2024年

作者： Peter EBENFELT Ming XIAO hang xu Department of Mathematics University of California at San Diego School of Mathematics (Zhuhai) Sun Yat-sen University

In this paper, we investigate analytic and geometric properties of obstruction flatness of strongly pseudoconvex CR hypersurfaces of dimension 2n-1. Our first two results concern local aspects. One asserts that any strongly pseudoconvex CR hypersurface M ? Cncan be osculated at a given point p ∈ M by an obstruction flat one up to order 2n + 4 generally and 2n + 5 if and only if p is an obstruction flat point. In the other result, we show that locally there are non-spherical but obstruction flat CR hypersurfaces with transverse symmetry for n = 2. The final main result in this paper concerns the existence of obstruction flat points on compact, strongly pseudoconvex, 3-dimensional CR hypersurfaces. It asserts that the unit sphere in a negative line bundle over a Riemann surface X always has at least one circle of obstruction flat points.

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Teaching Reform and Exploration of Practical Courses Based on Programmable Control

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Journal of Contemporary Educational Research 2024年第6期8卷 211-215页

作者： hang xu Zhuhai College of Science and Technology Zhuhai 519041Guangdong ProvinceChina

As the country continues to promote the development of intelligent manufacturing,all industries are carrying out enterprise automation upgrading,the Pearl River Delta Intelligent Manufacturing Conference held in March 2024 provides a direction guide for each enterprise on how to integrate the intelligent manufacturing technology into each link and provide direction guidance for enterprises to create new models and new business formats.College teachers,in focusing on the teaching process,should closely match the enterprise and social needs and cultivate excellent students.As the core controller of automation control,the application of programmable controllers in teaching is particularly important.In practical classes,by setting progressive difficulty,project guidance,team collaboration,and other links,students can master the automation equipment design of programmable control in repeated practice.

关键词： Programmable controller Practical course Project guidelines Teamwork

Shared mooring systems for offshore floating wind farms: A review

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Energy Reviews 2024年第1期3卷 76-89页

作者： hang xu Shengjie Rui Kanmin Shen Liangliang Jiang Haojie Zhang Long Teng Zhejiang Key Laboratory of Offshore Geotechnics and Material College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou310058China Norwegian Geotechnical Institute Sandakerveien 140Oslo0484Norway PowerChina Huadong Engineering Corporation Limited Hangzhou311122China Department of Chemical and Petroleum Engineering The University of CalgaryCalgaryAlbertaCanada

Offshore wind energy,as a form of renewable power,has seen rapid development in recent years.While fixedbottom wind turbines are typically used in water depths less than 50 m,the utilization of floating offshore wind turbines(FOWTs)becomes essential for deeper waters.Secure and effective mooring systems play a crucial role in making FOWTs commercially viable.The concept of a shared mooring system offers an innovative solution for deploying floating wind farms in clusters or arrays,which can reduce overall construction costs for large-scale floating wind farms.It is imperative to optimize the shared mooring arrangement for maximum cost-effectiveness and wind farm stability.However,implementing a shared mooring system introduces complexity to the dynamics of FOWTs,requiring the development of advanced simulation tools to meet modelling requirements.Under the shared mooring arrangement,mooring lines and anchors face more significant challenges,such as chain-seabed interactions,soil cyclic weakening,and anchor out-of-plane loading,which underscore the need for innovative,reliable,and efficient shared anchor designs.This article offers an overview of the current research status on shared mooring systems for floating wind farms,which might serve as a valuable reference for the construction of large-scale floating wind farms worldwide.

关键词： Floating offshore wind turbines Wind farm Shared mooring Shared anchor Renewable energy

Pre-MASLD:Should it be defined separately?

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 1-3页

作者： hang-Kai Huang You-Ming Li Cheng-Fu xu Department of Gastroenterology Zhejiang Provincial Clinical Research Center for Digestive Diseasesthe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Nonalcoholic fatty liver disease(NAFLD)is one of the most common chronic liver diseases,yet it has not received sufficient attention[1].Over the past two decades,the overall global prevalence of NAFLD has risen from 25%to 37%[2].The disease burden of NAFLD is fueled by the epidemic of obesity and diabetes[3].It is estimated that more than half of patients with diabetes have NAFLD.

关键词： NAFLD liver diseases

Continuous preparation of strong and tough PVA nanocomposite fibers by mechanical stretching-assisted salting-out treatment

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Nano Research 2024年第4期17卷 3156-3163页

作者： hang Chen Guangze Yang Yingzhi Sun Yichao xu Mingjie Liu Key Laboratory of Bioinspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191China Research Institute for Frontier Science Beihang UniversityBeijing 100191China International Research Institute for Multidisciplinary Science Beihang UniversityBeijing 100191China

Polymer composite fibers with superior properties such as excellent combined strength and toughness and biocompatibility can be used in high-tech applications of braided protective devices and smart wearable,however the research of high-performance polymer composite fiber remains in the infant stage.Here we present a strategy to produce strong and tough anisotropic polymer nanocomposite fibers with orientedly aligned salt rods using mechanical stretching-assisted salting-out treatment.The prepared nanocomposite fibers have a tensile strength of up to 786±2.7 MPa and an elongation at break of 81%,and the anisotropic fibers exhibit good transmission of mechanical vibration in the longitudinal direction with high resolution.During the fabrication process,the salt builds up into oriented rods during the directional salting process,and the polymer is confined to the 150 nm domain between the rods after the solvent is completely evaporated,giving the nanocomposite fibers superior mechanical properties.The presented strategy can be applied to the continuous mass production of nanocomposite fibers and is also generalizable to other polymer nanocomposites,which could extend the applicability of nanocomposite fibers to conditions involving more demanding mechanical loading and mechanical vibration transmission.

关键词： poly(vinyl alcohol)(PVA)nanofibers oriented structure ultrastrong and stiff mechanical vibration transmission salting out continuous production

Patterns and drivers of plant sexual systems in the dry-hot valley region of southwestern China

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Plant Diversity 2024年第2期46卷 158-168页

作者： Rong Ma Qi xu Yongqian Gao Deli Peng hang Sun Bo Song State Key Laboratory of Plant Diversity and Specialty Crops/Yunnan Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Populations Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China College of Life Sciences Shaanxi Normal UniversityXi'an 710119China Yunnan Forestry Technological College Kunming 650224China School of Life Science/Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment Yunnan Normal UniversityKunming 650500YunnanChina

Sexual systems play important roles in angiosperm evolution and exhibit substantial variations among different floras. Thus, studying their evolution in a whole flora is crucial for understanding the formation and maintenance of plant biodiversity and predicting its responses to environmental change. In this study, we determined the patterns of plant sexual systems and their associations with geographic elements and various life-history traits in dry-hot valley region of southwestern China, an extremely vulnerable ecosystem. Of the 3166 angiosperm species recorded in this area, 74.5% were hermaphroditic,13.5% were monoecious and 12% were dioecious, showing a high incidence of diclinous species. Diclinous species were strongly associated with tropical elements, whereas hermaphroditic species were strongly associated with temperate and cosmopolitan elements. We also found that hermaphroditism was strongly associated with showy floral displays, specialist entomophily, dry fruits and herbaceous plants.Dioecy was strongly associated with inconspicuous, pale-colored flowers, generalist entomophily, fleshy fruits, and woody plants, whereas monoecy was strongly associated with inconspicuous, pale-colored flowers, anemophily, dry fruits, and herbaceous plants. In addition, hermaphroditic species with generalist entomophily tended to flower in the dry season, whereas diclinous species with specialist entomophily tended to flower in the rainy season. However, independent of sexual systems, plants that produce dry fruits tended to flower in the rainy season and set fruits in the dry season, but the opposite pattern was found for fleshy fruit-producing plants. Our results suggest that in the dry-hot valleys, plant sexual systems are associated with geographic elements as well as various life-history traits that are sensitive to environmental change.

关键词： Floral traits Fruit type Growth form Pollination system Reproductive phenology