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Bacterial Biorefineries:Transforming Agro-Industrial Waste into Sustainable Solutions for a Circular Bioeconomy
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作者 Sevakumaran Vigneswari Muhammad Shahrul Md Noor +7 位作者 Fazilah Ariffin Azila Adnan Amirah Alias Lakshmanan Muthulakshmi Hemalatha Murugaiah Nor Omaima Harun Nurul Nadhirah Ruzelan Lakshiminarayanan Rajamani 《Journal of Renewable Materials》 2026年第3期98-122,共25页
The escalating accumulation of agro-industrial waste—exceeding 350 million tons annually from post-harvest residues,food processing,and aquaculture—poses serious environmental threats,including greenhouse gas emissi... The escalating accumulation of agro-industrial waste—exceeding 350 million tons annually from post-harvest residues,food processing,and aquaculture—poses serious environmental threats,including greenhouse gas emissions,groundwater contamination,and excessive landfill usage.Although conventional treatment methods such as composting,incineration,and recycling offer partial mitigation,they often fall short of delivering scalable,circular solutions.Microbial biorefineries have emerged as a transformative approach,enabling the conversion of diverse biomass streams into high-value renewable materials.Through microbial fermentation,agricultural and municipal waste can be repurposed into functional outputs such as nanocellulose,biochar,and biocompatible compounds with applications in packaging,pharmaceuticals,and cosmetics.This review critically examines the role of microbial systems in agro-waste valorization,highlighting recent advances in strain engineering,process integration,and bioproduct development.It also explores the regulatory and techno-economic frameworks required to scale these innovations within a biomass-driven circular economy,positioning microbial biorefineries as key enablers of sustainable material transitions. 展开更多
关键词 Agro-waste BIOECONOMY environmental sustainability circular economy
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Open-loop control of combustion instabilities in a full-scale annular ramjet combustor using linear genetic programming
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作者 Jianguo TAN Zheng XU +2 位作者 Yao LIU Dongdong ZHANG Yi HOU 《Chinese Journal of Aeronautics》 2026年第2期20-28,共9页
The operational demands of a wide range significantly exacerbate combustion instability issues within ramjet combustor.To suppress combustion oscillations,an open-loop control system utilizing Linear Genetic Programmi... The operational demands of a wide range significantly exacerbate combustion instability issues within ramjet combustor.To suppress combustion oscillations,an open-loop control system utilizing Linear Genetic Programming(LGP)has been developed for a full-scale annular ramjet combustor.The LGP is used to generate control laws that include multi-frequency forcing.These laws are then transformed into square waves to actuate the solenoid valve,which modulates the kerosene supply for open-loop control.The results show that the duty cycle has little effect on instability amplitude,whereas an increase in frequency leads to a remarked reduction in combustion amplitude.After five generations evolvements,the pressure amplitude is reduced by 40.6% under the optimal control law generated by LGP.Furthermore,the machine learning process is depicted using a proximity map of control law similarity,with the search pathway visualized by the steepest descent.All individuals go forward to the upper left corner of the map with the evolution process,terminating at the optimal individual of the fifth generation. 展开更多
关键词 annular ramjet combustor Combustion instabilities Linear genetic programming Machine learning Open-loop control
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Circular Economy Strategies for Reducing Environmental Footprints:Global Policies,Practices,and Barriers
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作者 Yi Su 《Journal of Environmental & Earth Sciences》 2026年第1期92-116,共25页
The circular economy is an innovative concept of both production and consumption.It can reduce wastage,preserve resources,and minimize environmental effects with the help of recycling,recovering resources,and extendin... The circular economy is an innovative concept of both production and consumption.It can reduce wastage,preserve resources,and minimize environmental effects with the help of recycling,recovering resources,and extending the life of products.It works as a pathway to reduce environmental footprints by redesigning production-consumption systems.This review critically examines global circular economy strategies,policy approaches,and persistent barriers that shape environmental footprint outcomes across major sectors.Drawing on a structured narrative review and thematic synthesis,we integrate findings on key circular economy practices,Eco-design,product life extension,reuse,re-manufacturing,recycling,and resource recovery,and assess how they interact with policy instruments such as extended producer responsibility,ecodesign requirements,and waste governance reforms.The analysis highlights that reported benefits(e.g.,reduced material throughput,waste generation,and emissions)are frequently constrained by technological limitations(complex material streams,low-quality recyclate,energy-intensive processing),economic conditions(high upfront costs,weak markets for secondary materials,commodity price volatility),and institutional and behavioral factors(regulatory fragmentation,limited enforcement capacity,low consumer acceptance).We further synthesize methodological challenges in measuring“circularity”and footprint reductions,emphasizing boundary choices,rebound effects,and trade-offs such as increased energy demand or land and water pressures in bio-based substitution.By linking circular economy strategies,barriers,and outcomes in an integrative conceptual framework,the review clarifies why circular transitions often deliver partial gains and identifies leverage points for scaling effective,evidence-based policy and practice. 展开更多
关键词 circular Economy Resource Recovery RECYCLING Policy Barriers Sustainable Development
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Circular Economy and Ecosystem Services:Advancing Sustainable Resource Management for the Future
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作者 Daoling Zhang 《Journal of Environmental & Earth Sciences》 2026年第2期202-228,共27页
The concepts of the circular economy(CE)are actively popularized as ways of minimizing waste products and the need to rely on virgin resources.Nevertheless,their sustainability is doubtful at a general level where eco... The concepts of the circular economy(CE)are actively popularized as ways of minimizing waste products and the need to rely on virgin resources.Nevertheless,their sustainability is doubtful at a general level where ecosystem functioning and ecosystem services(ES)are not given explicit attention.This review will combine both conceptual and empirical evidence of the connection between CE interventions and ES outcomes to enable more sustainable management of resources.We describe the effects of the CE strategies on the key environmental pressure pathways,altering ecosystem conditions,and impacting the delivery of regulating,provisioning,and cultural ecosystem services using a pressure condition-service framework.Analysis reveals that demand-side reduction and product life-extension strategies tend to offer more consistent ecosystem service co-benefits than recycling and recovery strategies because they do not involve production,and will cause less disturbance to the upstream environment.Contrastingly,recycling and recovery sustainability performance is highly dependent on the sources of energy,intensity of processing,and the safety of materials.Bio-based circularity has the potential to increase soil functionality and nutrient cycling,and mass application will result in trade-offs in terms of land competition and nutrient leakage.The sectoral analysis identifies the unique opportunities and threats in the agri-food systems,the built environment,plastics and textiles,electronics and critical minerals,and water and wastewater systems in terms of the burden displacement,local environmental pressures,and equity concerns.Harmonized reporting,coupled with supply-chain and spatial ecological assessment,threshold-conscious strategies that promote safe and regenerative circular systems should be put into the line of future research. 展开更多
关键词 circular Economy Ecosystem Services Natural Capital Sustainable Resource Management Regenerative Sustainability
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Therapeutic potential of circular RNAs in neurovascular remodeling after stroke
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作者 Zhenguo Yang Chi Kwan Tsang 《Neural Regeneration Research》 2026年第4期1550-1551,共2页
Stroke-induced alterations in cerebral blood flow trigger neurovascular remodeling,as manifested by the blood-brain barrier dysfunction and subs equent neurovascular repair activities such as angiogenesis.This process... Stroke-induced alterations in cerebral blood flow trigger neurovascular remodeling,as manifested by the blood-brain barrier dysfunction and subs equent neurovascular repair activities such as angiogenesis.This process involves neurovascular communication that facilitates the transport of mediators among cerebrovascular endothelial cells,pericytes,glial cells,and neurons,thereby transmitting signals from donor to recipient cells to elicit a collaborative response. 展开更多
关键词 therapeutic elicit collaborative response RNAS neurovascular communication neurovascular repair activities cerebrovascular endothelial cellspericytesglial neurovascular remodelingas circular
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基于时域同步平均的Circular图分析方法及齿轮故障智能诊断研究
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作者 胥永刚 张翼飞 +1 位作者 孙国栋 张坤 《机械强度》 北大核心 2025年第6期11-16,共6页
齿轮Circular图是用于与时域同步平均(Time Synchronous Averaging,TSA)相结合的一种结果呈现方法,可以将TSA提取到的齿轮啮合振动波形直观、清晰地展现出来。针对齿轮Circular图绘制参数设置和其缺少量化指标的问题,提出了用于波形边... 齿轮Circular图是用于与时域同步平均(Time Synchronous Averaging,TSA)相结合的一种结果呈现方法,可以将TSA提取到的齿轮啮合振动波形直观、清晰地展现出来。针对齿轮Circular图绘制参数设置和其缺少量化指标的问题,提出了用于波形边缘识别的F_(i)指标和基于Hu氏不变矩的Y_(i)指标。首先,使用TSA算法提取出齿轮啮合振动信号,通过计算最小F_(i)指标确定振动信号波形的上、下边缘;其次,利用上、下边缘参数绘制齿轮Circular图;再次,将齿轮Circular图分割为4个部分,通过计算分割后图片的Hu氏不变矩得到齿轮Circular图的Y_(i)指标;最后,基于从齿轮Circular图中提取出的Y_(i)和F_(i)指标,使用K最近邻(K-Nearest Neighbor,KNN)分类器对齿轮振动信号进行分类。仿真信号及齿轮断齿、裂纹故障信号的处理结果表明了该方法的有效性。 展开更多
关键词 齿轮箱 齿轮circular 特征指标 智能故障诊断
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AXISYMMETRIC BENDING OF TWO-DIRECTIONAL FUNCTIONALLY GRADED CIRCULAR AND ANNULAR PLATES 被引量:6
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作者 Guojun Nie Zheng Zhong 《Acta Mechanica Solida Sinica》 SCIE EI 2007年第4期289-295,共7页
Assuming the material properties varying with an exponential law both in the thick- ness and radial directions, axisymmetric bending of two-directional functionally graded circular and annular plates is studied using ... Assuming the material properties varying with an exponential law both in the thick- ness and radial directions, axisymmetric bending of two-directional functionally graded circular and annular plates is studied using the semi-analytical numerical method in this paper. The deflections and stresses of the plates are presented. Numerical results show the well accuracy and convergence of the method. Compared with the finite element method, the semi-analytical nu- merical method is with great advantage in the computational efficiency. Moreover, study on ax- isymmetric bending of two-directional functionally graded annular plate shows that such plates have better performance than those made of isotropic homogeneous materials or one-directional functionally graded materials. Two-directional functionally graded material is a potential alternative to the one-directional functionally graded material. And the integrated design of materials and structures can really be achieved in two-directional functionally graded materials. 展开更多
关键词 two-directional functionally graded materials circular and annular plates axisym-metric bending semi-analytical numerical method integrated design
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A transient bulk flow model with circular whirl motion for rotordynamic coefficients of annular seals 被引量:7
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作者 Peng XIA Zhansheng LIU +1 位作者 Xiangyu YU Jingming ZHAO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第5期1085-1094,共10页
Bulk flow model with perturbation simplification has been used to calculate rotordynamic coefficients in annular seals which have significant influences on the dynamic behavior of rotors in turbomachinery. In this wor... Bulk flow model with perturbation simplification has been used to calculate rotordynamic coefficients in annular seals which have significant influences on the dynamic behavior of rotors in turbomachinery. In this work, a transient bulk flow model with arbitrary rotor motion is developed, and the boundary conditions and friction factor in the model are calibrated with steady Computational Fluid Dynamics(CFD) analysis. The numerical solution scheme is developed based on the finite element method to obtain the transient reaction force in the seal clearance. With a periodic circular rotor orbit, the transient forces at multiple whirling frequencies are used to evaluate the rotordynamic coefficients. The leakage flowrate of CFD analysis has good agreement with experimental results and the calibrated parameters in bulk flow model are dependent on operating conditions. Although CFD calibration improves the accuracy of the perturbed bulk flow model, the direct damping is overestimated and the cross-coupled damping is underestimated. Compared with the perturbed model, the predictions of the transient bulk flow model are more agreeable with the experiment. 展开更多
关键词 annular seals Bulk flow Computational Fluid Dynamics(CFD) Rotordynamic TURBULENCE
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Error Analysis of Liquid Holdup Measurement in Gas-Liquid Annular Flow Through Circular Pipes Using High-Speed Camera Method 被引量:3
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作者 LIU Li BAI Bofeng 《Journal of Shanghai Jiaotong university(Science)》 EI 2018年第S1期34-40,共7页
Accurate measurement of gas-liquid phase fraction is essential for the proper modelling of the pressure drop, heat transfer coefficient, mass transfer rate and interfacial area in two-phase flows. In this paper, takin... Accurate measurement of gas-liquid phase fraction is essential for the proper modelling of the pressure drop, heat transfer coefficient, mass transfer rate and interfacial area in two-phase flows. In this paper, taking the issue of optical distortion into account, an analytical model was proposed to estimate and correct the liquid holdup in gas-liquid annular flow through a circular pipe using high-speed camera method. The error in the liquid holdup measurement generated from different refractive indices among transparent circular pipe, liquid film and air core was firstly theoretically analyzed based on the geometric optics. Experimental tests were then carried out to identify the difference as well as to validate the proposed model. Results indicated that the prediction of the liquid holdup has a good performance with the experimental data(i.e., mean relative error is 4.1%) and the measured liquid holdup is larger than the real one. It was found that the measured liquid holdup is larger than the real one. Generally, when the real liquid holdup gets smaller, the discrepancy between the measured liquid holdup by image and the real liquid holdup becomes more significant. Thus, after measuring the liquid holdup from the images, the value of the measured liquid holdup must be corrected by the present model in order to obtain the real liquid holdup. 展开更多
关键词 gas-liquid annular flow liquid holdup optical refraction analytical correction
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MAGNETOHYDRODYNAMIC PIPE FLOW IN DUCTS WITH PARTIAL CIRCULAR RING CROSS SECTION AND ANNULAR CROSS SECTION
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作者 Shu Yousheng, Department of Physics, Peking University, Beijing, ChinaQian Shangwu, Center of Theoretical Physics, CCAST (World Lab. ), Beijing Institute of Theoretical Physics, Academia Sinica, Beijing Department of Physics, Peking University, Beijing, China 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1990年第1期85-91,共7页
In this paper we use the Green function method to solve the problem of steady one dimensional flow of an incompressible viscous, electrically conducting fluid through a pipe with partial circular ring cross sec- tion ... In this paper we use the Green function method to solve the problem of steady one dimensional flow of an incompressible viscous, electrically conducting fluid through a pipe with partial circular ring cross sec- tion and one with annular cross section, in the presence of an applied transverse uniform magnetic field, We ob- tain analytic solutions and carry out some numerical calculations of the velocity distribution and induced magnet- ic field. 展开更多
关键词 magnetohydrodynamic pipe flow Green function method partial circular ring cross section annular cross section
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Aberration-corrected differential phase contrast microscopy with annular illuminations 被引量:1
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作者 Yao Fan Chenyue Zheng +6 位作者 Yefeng Shu Qingyang Fu Lixiang Xiong Guifeng Lu Jiasong Sun Chao Zuo Qian Chen 《Opto-Electronic Science》 2025年第8期2-12,共11页
Quantitative phase imaging(QPI)enables non-invasive cellular analysis by utilizing cell thickness and refractive index as intrinsic probes,revolutionizing label-free microscopy in cellular research.Differential phase ... Quantitative phase imaging(QPI)enables non-invasive cellular analysis by utilizing cell thickness and refractive index as intrinsic probes,revolutionizing label-free microscopy in cellular research.Differential phase contrast(DPC),a non-interferometric QPI technique,requires only four intensity images under asymmetric illumination to recover the phase of a sample,offering the advantages of being label-free,non-coherent and highly robust.Its phase reconstruction result relies on precise modeling of the phase transfer function(PTF).However,in real optical systems,the PTF will deviate from its theoretical ideal due to the unknown wavefront aberrations,which will lead to significant artifacts and distortions in the reconstructed phase.We propose an aberration-corrected DPC(ACDPC)method that utilizes three intensity images under annular illumination to jointly retrieve the aberration and the phase,achieving high-quality QPI with minimal raw data.By employing three annular illuminations precisely matched to the numerical aperture of the objective lens,the object information is transmitted into the acquired intensity with a high signal-to-noise ratio.Phase retrieval is achieved by an iterative deconvolution algorithm that uses simulated annealing to estimate the aberration and further employs regularized deconvolution to reconstruct the phase,ultimately obtaining a refined complex pupil function and an aberration-corrected quantitative phase.We demonstrate that ACDPC is robust to multi-order aberrations without any priori knowledge,and can effectively retrieve and correct system aberrations to obtain high-quality quantitative phase.Experimental results show that ACDPC can clearly reproduce subcellular structures such as vesicles and lipid droplets with higher resolution than conventional DPC,which opens up new possibilities for more accurate subcellular structure analysis in cell biology. 展开更多
关键词 quantitative phase imaging differential phase contrast aberration-corrected annular illumination
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美国Circularity Fuels公司在紧凑型装置中将沼气成功转化为合成气
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作者 汤玮健(摘译) 《石油炼制与化工》 北大核心 2025年第12期60-60,共1页
美国Circularity Fuels公司利用加州中央谷地一家奶牛场的沼气,通过一个紧凑型的电动处理装置,成功将其转化为合成气,这是可持续航空燃料(SAF)的关键前体。该装置的成本仅为传统蒸汽甲烷或自热重整器的1%。此次示范项目的成功标志着可... 美国Circularity Fuels公司利用加州中央谷地一家奶牛场的沼气,通过一个紧凑型的电动处理装置,成功将其转化为合成气,这是可持续航空燃料(SAF)的关键前体。该装置的成本仅为传统蒸汽甲烷或自热重整器的1%。此次示范项目的成功标志着可再生燃料的生产在经济性方面迈出了重要一步,Circularity公司认为这将有助于航空公司满足可持续燃料替代品的相关规定,同时为农民开辟数十亿美元的新收入来源。 展开更多
关键词 circularity Fuels 奶牛场 沼气 加州中央谷地
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Sludge Management: Integrating the Principle of Circular Economy into the Concept of Sustainability
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作者 Ludovico Spinosa 《Journal of Environmental Science and Engineering(A)》 CAS 2025年第1期53-59,共7页
The development of sustainable sludge management systems requires looking at them with a new vision in which the concepts of SD(Sustainable Development)must integrate those of CE(Circular Economy),both concepts subjec... The development of sustainable sludge management systems requires looking at them with a new vision in which the concepts of SD(Sustainable Development)must integrate those of CE(Circular Economy),both concepts subject to the principles of TD(Thermodynamics),thus allowing the adoption of actions that are all the more effective the more complete the evaluation of the social dimension has been.This involves a new“Way of thinking”which sees the sludge system as the“Locomotive”of the entire wastewater/sludge treatment train and is developed through“Ways of acting”which includes both“Technical”actions to maximize recoveries of useful materials and/or or energy,and“Socio/Institutional”actions to overcome barriers linked to local cultures and traditions,also considering that the specific local context heavily influences the choices capable of satisfying the concepts of CE.It follows the need of issuing realistic and applicable regulations and overcoming social barriers,such as lack of infrastructure and/or qualified personnel,to achieve an effective integration of the concepts of CE with the more general ones of sustainability. 展开更多
关键词 circular economy REGULATION sludge management STANDARDIZATION sustainability.
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Circular Economy in Municipal Solid Waste Management: Innovations and Challenges for Urban Sustainability
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作者 Richard Edmond Victor Sesay Ping Fang 《Journal of Environmental Protection》 2025年第2期35-65,共31页
Urban areas worldwide face escalating challenges in managing municipal solid waste (MSW) due to rapid urbanization, population growth, and changing consumption patterns. Inefficient waste management systems contribute... Urban areas worldwide face escalating challenges in managing municipal solid waste (MSW) due to rapid urbanization, population growth, and changing consumption patterns. Inefficient waste management systems contribute to environmental degradation, public health risks, and resource depletion, underscoring the need for innovative solutions. This review employing AI-driven sorting technologies in urban waste management as a transformative framework for sustainable MSW management, emphasizing waste reduction, resource recovery, and closed-loop systems. The paper synthesizes existing literature, case studies, and technological advancements to explore strategies for integrating CE principles into MSW management. Key areas of focus include the application of emerging technologies such as artificial intelligence, machine learning, and big data analytics;advancements in waste-to-resource technologies;the development of scalable and adaptable CE models tailored to diverse urban contexts;and fostering collaboration among governments, private sectors, and communities. Findings highlight the potential of CE frameworks to minimize waste generation, enhance resource efficiency, and create resilient urban systems. However, significant barriers remain, including technological, financial, and policy challenges. The review concludes by identifying future research directions and actionable recommendations for stakeholders, aiming to advance the global transition toward sustainable urban waste management. 展开更多
关键词 circular Economy Municipal Solid Waste Urban Sustainability Emerging Technologies
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A Hierarchical Optimization Method for Deformation Force Monitoring Layout of Annular Parts
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作者 DAI Kaining LIU Changqing +3 位作者 WANG Enning ZHAO Zhiwei SALONITIS Konstantinos LI Yingguang 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第3期275-286,共12页
Obtaining residual stress is crucial for controlling the machining deformation in annular parts,and can directly influence the performance and stability of key components in advanced equipment.Since existing research ... Obtaining residual stress is crucial for controlling the machining deformation in annular parts,and can directly influence the performance and stability of key components in advanced equipment.Since existing research has achieved global residual stress field inference for components by using the deformation force-based method where the deformation force is monitored during the machining process,reliable acquisition of deformation force stll remains a significant challenge under complex machining conditions.This paper proposes a hierarchical optimization method for the layout of deformation force monitoring of annular parts.The proposed method establishes two optimization objectives by analyzing the relationship between the deformation force and the residual stress in annular parts,i.e.,equivalence and ilconditioning of solving process.Specifically,the equivalence of the monitored deformation force and residual stress in terms of effect on caused machining deformation is evaluated by local deformation,and the illconditioning is also optimized to enhance the stability of residual stress inference.Verification is implemented in both simulation and actual machining experiments,demonstrating effectiveness of the proposed layout optimization method in inferring residual stress field of annular parts with deformation force. 展开更多
关键词 residual stress annular part deformation force layout optimization
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Dual contour edge information fusion for 3D aircraft skin circular hole detection
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作者 LIU Hongjun ZHANG Naiwen +1 位作者 MENG Fanxi LI Boyuan 《Optoelectronics Letters》 2025年第2期105-112,共8页
To address the challenges of varied aircraft skin hole detection types and susceptibility to noise,this paper proposes a method based on the perspective of dual contour edge information fusion.The core method combines... To address the challenges of varied aircraft skin hole detection types and susceptibility to noise,this paper proposes a method based on the perspective of dual contour edge information fusion.The core method combines stereoscopic vision and structured light dual contour information consistently,focusing on extracting edge point information around the hole edge to achieve precise detection of circular holes.In this approach,a line multi-directional gradient feature detector (LMGFD) is introduced for locating the holes from plane stereoscopic image.Furthermore,we establish a three-dimensional (3D) circular hole detection method (BPCircle) based on the dual contour edge information fusion.Finally,experiments demonstrate that our proposed method achieves superior accuracy and robustness based on public benchmark dataset and our own collected standard IPCDS dataset (including two-dimensional (2D)images,3D point clouds,and measured data of three-coordinate measuring machine).The dataset and code can be found from https://github.com/Nicholsdqw/123. 展开更多
关键词 CONTOUR circular DUAL
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Numerical Simulation of Turbulent Heat Transfer in Concentric Annular Pipes
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作者 Jinping Xu Zhiyun Wang Mo Yang 《Frontiers in Heat and Mass Transfer》 2025年第4期1151-1163,共13页
In concentric annular pipes,the difference in curvature between the inner and outer wall surfaces creates significant variations in the heat transfer characteristics of the two surfaces.The simplifications of the Ditt... In concentric annular pipes,the difference in curvature between the inner and outer wall surfaces creates significant variations in the heat transfer characteristics of the two surfaces.The simplifications of the Dittus-Boelter equation for circular pipes make it unsuitable for the complex flow induced by the geometry and heat transfer coupling effects in annular pipes.This prevents it from accurately predicting the turbulent heat transfer in concentric annular pipes.This paper used realizableκ–εand low Reynolds number models to conduct numerical simulations of turbulent convective heat transfer in concentric annular pipes and circular pipes.The results indicated that the local heat transfer coefficient and Nusselt number of the inner wall surface of the annular pipe were both higher than those of the outer wall surface.The Darcy resistance coefficient decreased upon increasing the Reynolds number and increased with the inner diameter-to-outer diameter ratio.When using the equivalent diameter as the characteristic scale,the turbulent heat transfer correlation obtained from circular pipes produced significant errors when used to approximate the turbulent convective heat transfer in concentric annular pipes.This error was greater for the inner wall surface,especially when the inner and outer diameters were relatively small,as the Nusselt number error on the inner wall surface reached 60.62%.The error of the Nusselt number on the outer wall surface reached 19.51%. 展开更多
关键词 Turbulent flow realizableκ–ε concentric annular pipe Dittus-Boelter formula
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Circulating circular RNAs act as potential novel biomarkers for sepsis secondary to pneumonia:a prospective cohort study
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作者 Chunxue Wang Dianyin Yang +8 位作者 Yuxin Zhu Qian Yang Tong Liu Xiandong Liu Dongyang Zhao Xiaowei Bao Tiancao Dong Li Shao Lunxian Tang 《World Journal of Emergency Medicine》 2025年第2期144-152,共9页
BACKGROUND:Circulating biomarkers for sepsis are lacking,and research on circular RNAs(circR NAs)as potential biomarkers of pneumonia-induced sepsis is limited.This study aims to investigate the diagnostic and prognos... BACKGROUND:Circulating biomarkers for sepsis are lacking,and research on circular RNAs(circR NAs)as potential biomarkers of pneumonia-induced sepsis is limited.This study aims to investigate the diagnostic and prognostic potential of circRNAs in patients with pneumonia-induced sepsis.METHODS:This prospective cohort study included 40 healthy individuals,60 patients with pneumonia,and 80 patients with pneumonia-induced sepsis.CircRNAs identified through RNA-sequencing were validated using quantitative real-time polymerase chain reaction(qRT-PCR).Spearman correlation analysis was used to evaluate the associations between circRNAs,inflammatory markers,Sequential Organ Failure Assessment(SOFA)scores,and Acute Physiology and Chronic Health EvaluationⅡ(APACHEⅡ)scores.Receiver operating characteristic(ROC)curves analysis were used to assess the diagnostic performance of circRNAs,while ROC curves and Kaplan-Meier survival analysis were used to evaluate their prognostic value of 28-day mortality.RESULTS:qRT-PCR confirmed the significant upregulation of Circ-CTD-2281E23.2 and downregulation of Circ-0075723 and Circ-0008679 in sepsis patients.Spearman correlation analysis showed that Circ-CTD-2281E23.2 was positively correlated with inflammatory markers and severity scores,whereas Circ-0075723 and Circ-0008679 were negatively correlated with these parameters.The area under the curve(AUC)values for Circ-CTD-2281E23.2,Circ-0075723,and Circ-0008679 in diagnosing pneumonia-induced sepsis were 0.728,0.706,and 0.793,respectively.The combination of these circRNAs(AUC=0.846)and the combination with other clinical indicators(AUC=0.990)demostrated enhanced AUC values.The AUC values for Circ-CTD-2281E23.2 and Circ-0075723 in predicting 28-day mortality were 0.664 and 0.765,respectively.CONCLUSION:This study suggest the additional diagnostic and prognostic value of circRNAs in pneumonia-induced sepsis.Circ-CTD-2281E23.2,Circ-0075723,and Circ-0008679 exhibit diagnostic potential,with Circ-CTD-2281E23.2 and Circ-0075723 showing positive prognostic value for 28-day mortality in sepsis patients. 展开更多
关键词 circular RNAs BIOMARKER Pneumonia-induced sepsis Diagnosis Prognosis
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Optimizing circular rotations in confined systems via enhanced self-driven speed of active nematics
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作者 Tian Tang Chun-lai Ren Yu-qiang Ma 《Communications in Theoretical Physics》 2025年第3期157-164,共8页
Active matter exhibits collective motions at various scales.Geometric confinement has been identified as an effective way to control and manipulate active fluids,with much attention given to external factors.However,t... Active matter exhibits collective motions at various scales.Geometric confinement has been identified as an effective way to control and manipulate active fluids,with much attention given to external factors.However,the impact of the inherent properties of active particles on collective motion under confined conditions remains elusive.Here,we use a highly tunable active nematics model to study active systems under confinement,focusing on the effect of the self-driven speed of active particles.We identify three distinct states characterized by unique particle and flow fields within confined active nematic systems,among which circular rotation emerges as a collective motion involving rotational movement in both particle and flow fields.The theoretical phase diagram shows that increasing the self-driven speed of active particles significantly enhances the region of the circular rotation state and improves its stability.Our results provide insights into the formation of high quality vortices in confined active nematic systems. 展开更多
关键词 active nematics collective motion CONFINEMENT circular rotation
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Performance of a hybrid system with a semi-submersible wind platform and annular wave-energy converters
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作者 Binzhen ZHOU Yu WANG +3 位作者 Zhi ZHENG Peng JIN Lei WANG Yujia WEI 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第6期525-539,共15页
Installing annular wave-energy converters(WECs)on the columns of floating wind platforms in the form of a coaxial-cylinder provides a convenient means of integration.Extant coaxial-cylinder-type wind-wave hybrid syste... Installing annular wave-energy converters(WECs)on the columns of floating wind platforms in the form of a coaxial-cylinder provides a convenient means of integration.Extant coaxial-cylinder-type wind-wave hybrid systems are mostly based on single-column platforms such as spars(single coaxial-cylinder hybrid system'hereafter).Systems based on multiple-column platforms such as semi-submersible platforms('multiple coaxial-cylinder hybrid systems'hereafter)are rarely seen or studied,despite their superiority in wave-power absorption due to the use of multiple WECs as well as in dynamic stability.This paper proposes a novel WindFloat-annular-WEC hybrid system,based on our study investigating its dynamic and power features,and optimizing the geometry and power take-off of the WECs.Our results show that the dynamic and power features of a multiple coaxial-cylinder hybrid system are different from those of a single coaxial-cylinder hybrid system,so the same optimization parameters cannot be directly applied.Flatter annular WECs absorb slightly more power in a wider wave-period range,but their geometry is confined by limitations in installation and structural strength.The overall effect of an oblique incident wave is greater intensity in the motions of the hybrid system in yaw and the direction perpendicular to propagation,although the difference is small and maybe negligible. 展开更多
关键词 Semi-submersible wind platform Wave energy annular wave-energy converter(WEC) Power performance Motion
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