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Resilient performance of self-centering hybrid rocking walls with curved interface under pseudo-static loading

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 65-85页

作者： Su Xing yan Shi sun Xianglei wang Tao School of Civil Engineering Shenyang Jianzhu UniversityShenyang 110168China PetroChina East China Design Institute Co. Ltd.Qingdao 266000China Qingdao Country Garden Bolin Real Estate Co. Ltd.Qingdao 266100China

Frame and rocking wall(FRW)structures have excellent resilient performance during ***,the concrete at interfacial corners of rocking walls(RWs)is easily crushed due to local extreme compression during the rocking *** innovative RW with a curved interface is proposed to prevent interfacial corners from producing local damage,enhancing its earthquake resilient performance(ERP).The precast wall panel with a curved interface is assembled into an integral self-centering hybrid rocking wall(SCRW)by two post-tensioned unbonded prestressed ***,two ordinary energy dissipation steel rebars and two shear reinforcements are arranged to increase the energy dissipation capacity and lateral *** SCRW specimens and one monolithic reinforced concrete(RC)shear wall(SW)were tested under pseudo-static loading to compare the ERPs of the proposed SCRW and the SW,focusing on studying the effect of the curved interface on the *** key resilient performance of rocking effects,failure modes,and hysteretic properties of the SCRW were *** results show that nonlinear deformations of the SCRW are concentrated along the interface between the SCRW and the foundation,avoiding damage within the *** restoring force provided by the prestressed tendons can effectively realize self-centering capacity with small residual deformation,and the resilient performance of the SCRW is better than that of monolithic *** addition,the curved interface of the SCRW makes the rocking center change and move inward,partially relieving the stress concentration and crush of *** rocking range of the rocking center is about 41.4%of the width of the SCRW.

关键词： self-centering hybrid rocking wall(SCRW) monolithic shear wall(SW) earthquake resilient performance(ERP) curved interface rocking center

Customer Joining Behavior and Regulation Strategy in Visible Multi-Server Queues with Synchronous Vacations of Partial Servers

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Journal of Systems Science & Complexity 2024年第3期37卷 1209-1232页

作者： sun Wei wang Hao XIE Xumeng LI Shiyong School of Economics and Management Yanshan UniversityQinhuangdao 066004China

This paper studies customer joining behavior and system regulation strategy in nonexhaustive visible M/M/m queues with synchronous vacations of a part of the *** this part of the servers are idle,they take multiple vacations simultaneously(vacation period).Until there are customers waiting in the queue,they are reactivated and all servers are busy or idle(busy period).The authors call this part of the servers as“partial servers”.In view of the fully visible queue and the almost visible queue,the authors obtain customers’equilibrium joining threshold strategies and their socially optimal joining threshold strategies,respectively,and observe that customer joining behavior in equilibrium generally makes the system overcrowded,which makes the equilibrium social welfare lower than the optimal social *** regulation,interestingly,for optimizing social welfare,the system manager hopes not only customers arriving in vacation period pay attention to the number of partial servers,but also customers arriving in busy period should care about it rather than ***,arranging more servers for vacation does not necessarily lead to the decrease of social welfare on condition that the number of partial servers is close to *** for the information advantage of the fully visible case,it is not obvious for increasing social welfare and even unfavorable to servers’profit unless the number of partial servers is big ***,given the different composition of social welfare,there exists the optimal number of partial servers and the optimal arrival rate of customers for maximizing social welfare.

关键词： Customer behavior non-exhaustive service partial servers regulation strategy synchronous vacations visible queue

An improved high-fidelity adaptive model for integrated inlet-engine-nozzle based on mechanismdata fusion

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Chinese Journal of Aeronautics 2024年第8期37卷 190-207页

作者： Chen wang Ziyang YU Xian DU Ximing sun School of Control Science and Engineering Dalian University of TechnologyDalian 116024China Key Laboratory of Intelligent Control and Optimization for Industrial Equipment Ministry of EducationDalian University of TechnologyDalian 116024China

Nowadays,there has been an increasing focus on integrated flight propulsion control and the inlet-exhaust design for the aero-propulsion *** component-level models are inadequate due to installed performance deviations and mismatches between the real engine and the model,failing to meet the accuracy requirements of supersonic *** paper establishes a quasi-one-dimensional model for the inlet-exhaust system and conducts experimental ***,a mechanism-data fusion adaptive modeling scheme using an Extreme Learning Machine based on the Salp Swarm Algorithm(SSA-ELM)is *** study reveals the inlet model’s efficacy in reflecting installed performance,flow matching,and mitigating pressure distortion,while the nozzle model accurately predicts flow coefficients and thrust coefficients,and identifies various operational *** model’s output closely aligns with typical experimental *** combining offline optimization and online adaptive correction,the mechanismdata fusion adaptive model substantially reduces output errors during regular flights and varying levels of degradation,and effectively handles gradual degradation within a single flight ***,the mechanism-data fusion adaptive model holistically addresses total pressure errors within the inlet-exhaust system and normal shock location *** approach significantly curbs performance deviations in supersonic *** example,at Ma=2.0,the system error impressively drops from 34.17%to merely 6.54%,while errors for other flight conditions consistently stay below the 2.95%*** findings underscore the clear superiority of the proposed method.

关键词： Aero-propulsion system Integrated inlet-enginenozzle Component-level model On-board adaptive model Mechanism-data fusion Extreme learning machine

Comprehensive Exergoeconomic Analysis and Optimization of a Novel Zero-Carbon-Emission Multi-Generation System based on Carbon Dioxide Cycle

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Journal of Thermal Science 2024年第3期33卷 1065-1081页

作者： sun yan LI Hongwei wang Di DU Changhe School of Energy and Power Engineering Northeast Electric Power UniversityJilin132012China School of Automation Engineering Northeast Electric Power UniversityJilin132012China Xi’an Institute of Electromechanical Information Technology Xi’an710065China

This paper aims to conduct a comprehensive exergoeconomic analysis of a novel zero-carbon-emission multi-generation system and propose a fast optimization method combined with machine *** detailed exergoeconomic analysis of a novel combined power,freshwater and cooling multi-generation system is performed in this *** exergoeconomic analysis model is established by exergy flow theory.A comprehensive exergy,exergoeconomic and environmental analysis is carried *** critical decision variables are researched to bring out effects on the multi-generation system exergoeconomic performance.A novel fast optimization method combining genetic algorithm and Bagging neural network is *** advanced nature comparison is made between the proposed system and four similar *** display that increasing the turbine inlet temperature can improve exergy efficiency and decrease the total product unit *** multi-generation system exergy destruction directly determines exergy efficiency and total exergy destruction cost *** total product unit cost in the cost optimal design case is reduced by 7.7%and 25%,respectively,compared with exergy efficiency optimal design case and basic design *** with four similar cases,the proposed multi-generation system has great advantages in thermodynamic performance and exergoeconomic *** paper can provide research methods and ideas for performance analysis and fast optimization of multi-generation system.

关键词： waste heat recovery exergoeconomic analysis supercritical carbon dioxide optimization machine learning

Effect of nourishing Yin and purging fire Chinese herbal mixture on delaying light-induced premature puberty in rats

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Journal of Traditional Chinese Medicine 2024年第1期44卷 95-102页

作者： sun yanyan XUE Yuanyuan sun Wen wang Yonghong YU Jian Department of Traditional Chinese Medicine Children's Hospital of Fudan UniversityShanghai 201102China Department of Pediatrics Zibo Central HospitalZibo 255000China

OBJECTIVE:To elucidate the mechanism of the nourishing Yin and purging fire Chinese herbal mixture(NYPF)in delaying light-induced premature puberty in ***:Twenty-one days old female SpragueDawley rats were randomly assigned to normal group(N),long light exposure group(L),NYPF and normal saline group(NS).Rats in the L,NYPF and NS groups were exposed to 16 h:350 lux light/8 h:dark,while rats in the N group were exposed to 12 h:50 lux light/12 h:*** and normal saline was administered to the rats in the NYPF group or NS group,respectively,from day *** rats in every group were sacrificed at 9 *** day 28(P28),on the day when rat's vulva opened in the L group(L-VO),on the day when the first estrous interphase occurred in rats of L group(L-E1),and on the day when the second estrous interphase occurred in rats of L group(L-E2),***:On day 34,all rats in the L group,80%of rats in the NS group,40%of rats in the N group,and 20%of rats in the NYPF group showed complete opening of the *** P28,m RNA level of hypothalamic kisspeptin(Kiss-1)in the L group was significantly higher than that in the N group(P<0.05).The rats in the L and NS groups had significantly lower hypothalamic argininephenylalanine-amide(RFamide)-related peptide 3(RFRP-3)m RNA levels than those in the N group(P<0.05),whereas RFRP-3 m RNA level was significantly higher in the NYPF group than that in the L group(P<0.05).At L-VO,the ovarian index of the L and NS groups was significantly higher than that of the N group(P<0.05)and estradiol(E2)level of the NYPF group was significantly lower than that of the N and NS groups(P<0.05);hypothalamic Kiss-1 m RNA level in the L and NS groups was significantly higher than that in the N and NYPF groups(P<0.05),whereas hypothalamic RFRP-3 m RNA level in the L,NYPF,and NS groups was significantly lower than that in the N group(P<0.05).At L-E1,E2 level of the L and NS groups was significantly higher than that of the N group(P<0.01),wher

关键词： light puberty precocious kisspeptins RFRP-3 melatonin Nourishing Yin and Purging Fire

Numerical study on the cavity dynamics for vertical water entries of twin spheres

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Defence Technology（防务技术） 2024年第2期32卷 459-472页

作者： Xu wang Xujian Lyu Ruisheng sun Dongdong Tang School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing210094China Shanghai Institute of Spacecraft Equipment Shanghai200240China

In this study, a three dimensional(3D) numerical model of six-degrees-of-freedom(6DOF) is applied to simulate the water entries of twin spheres side-by-side at different lateral distances and time *** turbulence structure is described using the shear-stress transport k-ω(SST k-ω) model, and the volume of fluid(VOF) method is used to track the complex air-liquid interface. The motion of spheres during water entry is simulated using an independent overset grid. The numerical model is verified by comparing the cavity evolution results from simulations and experiments. Numerical results reveal that the time interval between the twin water entries evidently affects cavity expansion and contraction behaviors in the radial direction. However, this influence is significantly weakened by increasing the lateral distance between the two spheres. In synchronous water entries, pressure is reduced on the midline of two cavities during surface closure, which is directly related to the cavity volume. The evolution of vortexes inside the two cavities is analyzed using a velocity vector field, which is affected by the lateral distance and time interval of water entries.

关键词： Twin water entries Side-by-side Cavity Numerical simulation

Elucidating solvent effects on the stability of phenoxyl radicals in monohydric alcohols via electron paramagnetic resonance

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Green Chemical Engineering 2024年第4期5卷 483-488页

作者： Xinyu wang Wenjing sun Yongtao wang Haoran Li Department of Chemistry Zhejiang University Center of Chemistry for Frontier Technologies ZJU-NHU United R&D Center Zhejiang University State Key Laboratory of Chemical Engineering College of Chemical and Biological Engineering Zhejiang University

Research on solvent effects is an important and long-standing topic, but there still is some room, especially for the special solvent effect of fluoroalcohols. In this work, we investigated the stability of phenoxyl radical in monohydric alcohol solvents through in-situ electron paramagnetic resonance detections. The decay behavior of phenoxyl radical showed a reasonable relationship with the mesoscopic structure of alcohols, characterized by smalland wide-angle X-ray scattering. Moreover, the distinct solvent effects of fluoroalcohols were emphasized, and the significant influence of van der Waals distance in the solvents was suggested. Overall, the stability of phenoxyl radical in alcohols was quantified and correlated with the solvent structures. We believe that the established method for stability study on radicals will encourage solvent effect studies on various organic reactions, and the proposed solvent effects in fluoroalcohols may inspire the development of green solvents in both industrial conversions and organic synthesis.

关键词： Solvent effect Fluoroalcohol Phenoxyl radical Stability Electron paramagnetic resonance

Crocus genome reveals the evolutionary origin of crocin biosynthesis

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1878-1891页

作者： Zhichao Xu Shanshan Chen yalin wang ya Tian Xiaotong wang Tianyi Xin Zishan Li Xin Hua Shengnan Tan Wei sun Xiangdong Pu Hui yao Ranran Gao Jingyuan Song Key Lab of Chinese Medicine Resources Conservation State Administration of Traditional Chinese Medicine of the People's Republic of ChinaInstitute of Medicinal Plant DevelopmentChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100193China State Key Laboratory of Basis and New Drug Development of Natural and Nuclear Drugs Engineering Research Center of Chinese Medicine ResourceMinistry of EducationBeijing 100193China College of Life Science Northeast Forestry UniversityHarbin 150040China Key Laboratory of Beijing for Identification and Safety Evaluation of Chinese Medicine China Academy of Chinese Medical SciencesInstitute of Chinese Materia MedicaBeijing 100700China Analysis and Testing Center of Northeast Forestry University Harbin 150040China School of Pharmacy Anhui Medical UniversityInflammation and Immune Mediated Diseases Laboratory of Anhui ProvinceHefei 230032China

Crocus sativus (saffron) is a globally autumn-flowering plant, and its stigmas are the most expensive spice and valuable herb medicine. Crocus specialized metabolites, crocins, are biosynthesized in distant species, Gardenia (eudicot) and Crocus (monocot), and the evolution of crocin biosynthesis remains poorly understood. With the chromosome-level Crocus genome assembly, we revealed that two rounds of lineage-specific whole genome triplication occurred, contributing important roles in the production of carotenoids and apocarotenoids. According to the kingdom-wide identification, phylogenetic analysis, and functional assays of carotenoid cleavage dioxygenases (CCDs), we deduced that the duplication, site positive selection, and neofunctionalization of Crocus-specific CCD2 from CCD1 members are responsible for the crocin biosynthesis. In addition, site mutation of CsCCD2 revealed the key amino acids, including I143, L146, R161, E181, T259, and S292 related to the catalytic activity of zeaxanthin cleavage. Our study provides important insights into the origin and evolution of plant specialized metabolites, which are derived by duplication events of biosynthetic genes.

关键词： Crocus sativus WGT Crocin biosynthesis Carotenoids Apocarotenoids CCDs

Design and Control of an Autonomous Bat-like Perching UAV

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Journal of Bionic Engineering 2024年第3期21卷 1253-1264页

作者： Long Bai Wei wang Xiaohong Chen Yuanxi sun State Key Laboratory of Mechanical Transmission Chongqing UniversityChongqing400044China

Perching allows small Unmanned Aerial Vehicles(UAVs)to maintain their altitude while significantly extending their flight duration and reducing ***,current research on flying habitats is poorly adapted to unstructured environments,and lacks autonomous capabilities,requiring ideal experimental environments and remote control by *** solve these problems,in this paper,we propose a bat-like UAV perching mechanism by investigating the bat upside-down perching method,which realizes double self-locking in the perching state using the ratchet and four-link dead point *** on this perching mechanism,this study proposes a control strategy for UAVs to track targets and accomplish flight perching autonomously by combining a binocular camera,single-point LiDAR,and pressure *** perching experiments were conducted for crossbar-type objects *** experimental results show that a multirotor UAV equipped with the perching mechanism and sensors can reliably achieve autonomous flight perching and re-flying off the target *** power consumption is reduced to 2.9%of the hovering state when perched on the target object.

关键词： Bio-inspired design Perching mechanism UAV Autonomous flight