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B(E2) Saturation in the Rare-Earth Region

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Chinese Physics Letters 1997年第5期14卷 340-343页

作者： long Gui-lu Department of Physics Tsinghua UniversityBeijing 100084 Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100080

The quadrupole interactions between neutrons and protons are calculated using Nilsson+BCS model for the neutron-rich even-even rare-earth *** is used to study the saturation of B(E2)'s in this mass *** neutron numbers at which saturation of B(E2)occurs are calculated for each isotopic *** particular,the calculation suggests that B(E2)saturation may occur in the 2nd half of the 82-126 major shell in erbium and ytterbium.

关键词： B(E2) saturation Rare

A novel noise reduction technique for underwater acoustic signals based on complete ensemble empirical mode decomposition with adaptive noise,minimum mean square variance criterion and least mean square adaptive filter

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Defence Technology（防务技术） 2020年第3期16卷 543-554页

作者： Yu-xing Li long Wang Faculty of Information Technology and Equipment Engineering Xi'an University of TechnologyXi'an 710048ShaanxiChina School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072ShaanxiChina

Underwater acoustic signal processing is one of the research hotspots in underwater *** reduction of underwater acoustic signals is the key to underwater acoustic signal *** to the complexity of marine environment and the particularity of underwater acoustic channel,noise reduction of underwater acoustic signals has always been a difficult challenge in the field of underwater acoustic signal *** order to solve the dilemma,we proposed a novel noise reduction technique for underwater acoustic signals based on complete ensemble empirical mode decomposition with adaptive noise(CEEMDAN),minimum mean square variance criterion(MMSVC) and least mean square adaptive filter(LMSAF).This noise reduction technique,named CEEMDAN-MMSVC-LMSAF,has three main advantages:(i) as an improved algorithm of empirical mode decomposition(EMD) and ensemble EMD(EEMD),CEEMDAN can better suppress mode mixing,and can avoid selecting the number of decomposition in variational mode decomposition(VMD);(ii) MMSVC can identify noisy intrinsic mode function(IMF),and can avoid selecting thresholds of different permutation entropies;(iii) for noise reduction of noisy IMFs,LMSAF overcomes the selection of deco mposition number and basis function for wavelet noise ***,CEEMDAN decomposes the original signal into IMFs,which can be divided into noisy IMFs and real ***,MMSVC and LMSAF are used to detect identify noisy IMFs and remove noise components from noisy ***,both denoised noisy IMFs and real IMFs are reconstructed and the final denoised signal is *** with other noise reduction techniques,the validity of CEEMDAN-MMSVC-LMSAF can be proved by the analysis of simulation signals and real underwater acoustic signals,which has the better noise reduction effect and has practical application ***-MMSVC-LMSAF also provides a reliable basis for the detection,feature extraction,classification and recognition of underwater acousti

关键词： Underwater acoustic signal Noise reduction Empirical mode decomposition(EMD) Ensemble EMD(EEMD) Complete EEMD with adaptive noise(CEEMDAN) Minimum mean square variance criterion(MMSVC) Least mean square adaptive filter(LMSAF) Ship-radiated noise

Frequency Domain Fatigue Evaluation on SCR Girth-Weld Based on Structural Stress

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China Ocean Engineering 2024年第2期38卷 255-270页

作者： ZHANG long ZHAO Tian-feng College of Safety and Ocean Engineering China University of Petroleum(Beijing)Beijing 102249China

The Steel Catenary Riser(SCR)is a vital component for transporting oil and ga. from the seabed to the floating *** harsh environmental conditions and complex platform motion make the SCR’s girth-weld prone to fatigue *** structural stress fatigue theory and Master S-N curve method provide accurate predictions for the fatigue damage on the welded joints,which demonstrate significant potential and compatibility in multi-axial and random fatigue ***,we propose a new frequency fatigue model subjected to welded joints of SCR under multiaxial stress,which fully integrates the mesh-insensitive structural stress and frequency domain random process and transforms the conventional welding fatigue technique of SCR into a spectrum analysis technique utilizing structural ***,a full-scale FE model of SCR with welds is established to obtain the modal structural stress of the girth weld and the frequency response function(FRF)of modal coordinate,and a biaxial fatigue evaluation about the girth weld of the SCR can be achieved by taking the effects of multi-load correlation and pipe-soil interaction into *** research results indicate that the frequency-domain fatigue results are aligned with the time-domain results,meeting the fatigue evaluation requirements of the SCR.

关键词： SCR girth weld random vibration self(cross)power spectrum structural stress method biaxial fatigue damage

Jetting-based bioprinting:process,dispense physics,and applications

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Bio-Design and Manufacturing 2024年第5期7卷 771-799页

作者： Wei long Ng Viktor Shkolnikov Singa.ore Centre for 3D Printing(SC3DP) School of Mechanical and Aerospace EngineeringNanyang Technological University(NTU)Singapore 639798Singapore HP Inc. Palo AltoCA 94304USA

Jetting-based bioprinting facilitates contactless drop-on-demand deposition of subnanoliter droplets at well-defined positions to control the spatial arrangement of cells,growth factors,drugs,and biomaterials in a highly automated layer-by-layer fabrication *** to its immense versatility,jetting-based bioprinting has been used for various applications,including tissue engineering and regenerative medicine,wound healing,and drug development.A lack of in-depth understanding exists in the processes that occur during jetting-based *** review paper will comprehensively discuss the physical considerations for bioinks and printing conditions used in jetting-based *** first present an overview of different jetting-based bioprinting techniques such as inkjet bioprinting,laser-induced forward transfer bioprinting,electrohydrodynamic jet bioprinting,acoustic bioprinting and microvalve ***,we provide an in-depth discussion of various considerations for bioink formulation relating to cell deposition,print chamber design,droplet formation and droplet ***,we highlight recent accomplishments in jetting-based *** present the advantages and challenges of each method,discuss considerations relating to cell viability and protein stability,and conclude by providing insights into future directions of jetting-based bioprinting.

关键词： 3D bioprinting Biofabrication Jetting-based Dispense physics Machine learning

Cascade Enzymatic Hydrolysis Coupling with Ultrafine Grinding Pretreatment for Suga.cane Baga.se Saccharification

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Chinese Journal of Chemical Physics 2015年第3期28卷 355-360,I0002页

作者： Zheng-qiu Yuan Jin-xing long Tie-jun Wang Yu-qin Li Qi Zhang long-long Ma Key Laboratory of Renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Science Guangzhou 510640 China University of Chinese Academy of Science Beijing 100049 China School of Chemical EngineerinE Xiangtan University Xiangtan 411105 China

The biorefinery process for suga.cane baga.se saccharification generally requires signifcant accessibility of cellulose. We reported a novel method of cascade cellulase enzymatic hydrol- ysis coupling with ultrafine grinding pretreatment for suga.cane baga.se saccharification. Three enzymatic hydrolysis modes including single cellulase enzymatic hydrolysis, mixed cellulase enzymatic hydrolysis, and cascade cellulase enzymatic hydrolysis were compared. The changes on the functional group and surface morphology of baga.se during cascade cellulase enzymatic hydrolysis were also examined by FT-IR and SEM respectively. The results showed that cascade enzymatic hydrolysis was the most efficient way to enhance the suga.cane baga.se saccharification. More than 65% of reducing suga. yield with 90.1% of glucose selectivity was achieved at 50 ℃, pH=4.8 for 72 h （1200 r/min） with cellulase I of 7.5 FPU/g substrate and cellulase II of 5 FPU/g substrate.

关键词： Suga.cane baga.se Ultrafine grinding pretreatment Cascade enzymatic hydrolysis Reducing suga.s Glucose

Order-Preserved Preset-Time Cooperative Control:A Monotone System-Based Approach

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IEEE/CAA Journal of Automatica Sinica 2022年第9期9卷 1603-1611页

作者： Boda Ning Qing-long Han the Center for Smart Infrastructure and Digital Construction Swinburne University of TechnologyMelbourneVIC 3122Australia the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourneVIC 3122Australia

This paper is concerned with order-preserved preset-time cooperative control of multi-agent systems with directed graphs.A novel monotone system-based approach is proposed to preserve the initial order of agents while guaranteeing the preset-time state ***,three different distributed controllers together with sufficient conditions are designed to realize leaderless consensus,leader-following consensus,and containment control,*** proposed controllers facilitate preset-time deployment of agents in practical scenarios with collision avoidance *** studies through a numerical example are carried out to illustrate the effectiveness of the proposed controllers.

关键词： Collision-avoidance consensus multi-agent systems preset-time control

Designing Proportional-Integral Consensus Protocols for Second-Order Multi-Agent Systems Using Delayed and Memorized State Information

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 878-892页

作者： Honghai Wang Qing-long Han the College of Information Science and Engineering State Key Laboratory of Synthetical Automation for Process IndustriesNortheastern UniversityShenyang 110819China the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourneVIC 3122Australia

This paper is concerned with consensus of a secondorder linear time-invariant multi-agent system in the situation that there exists a communication delay among the agents in the network.A proportional-integral consensus protocol is designed by using delayed and memorized state *** the proportional-integral consensus protocol,the consensus problem of the multi-agent system is transformed into the problem of asymptotic stability of the corresponding linear time-invariant time-delay *** that the location of the eigenvalues of the corresponding characteristic function of the linear time-invariant time-delay system not only determines the stability of the system,but also plays a critical role in the dynamic performance of the *** this paper,based on recent results on the distribution of roots of quasi-polynomials,several necessary conditions for Hurwitz stability for a class of quasi-polynomials are first *** allowable regions of consensus protocol parameters are *** necessary and sufficient conditions for determining effective protocol parameters are *** designed protocol can achieve consensus and improve the dynamic performance of the second-order multi-agent ***,the effects of delays on consensus of systems of harmonic oscillators/double integrators under proportional-integral consensus protocols are ***,some results on proportional-integral consensus are derived for a class of high-order linear time-invariant multi-agent systems.

关键词： Consensus protocol Hurwitz stability multi-agent systems quasi-polynomials time delay

When Electronically Inert Polymers Meet Conjuga.ed Polymers:Emerging Opportunities in Orga.ic Photovoltaics

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Chinese Journal of Polymer Science 2022年第8期40卷 861-869,I0006页

作者： Jing-Jing Wang long Ye School of Materials Science&Engineering Tianjin Key Laboratory of Molecular Optoelectronic SciencesTianjin UniversityCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin300350China State Key Laboratory of Applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun130033China

Insulating polymers(commodity plastics in particular)are a major category of polymeric materials widely used in our daily life,but they exhibit abysmal electrical ***,conjuga.ed polymers are ga.ning tremendous interest due to their excellent electrical properties and versatile applications in orga.ic *** this perspective,we provide a concise account of the added value in orga.ic solar cells,as brought by the combined use of conjuga.ed and insulating *** challenging tasks and prospective directions are given to the potential benefits of employing insulating polymer additives,which spans from common commodity plastics to high-temperature resistant resins and thermoplastic ***,the inert polymers can improve many important properties such as mechanical and thermal robustness but not sacrifice optoelectronic performance.

关键词： Orga.ic solar cells Insulating polymers Photovoltaic polymers Miscibility Morphology

Potential Hydrodynamic Performance Enhancement of Hydrokinetic Turbine with Hydrophobic Coatings

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China Ocean Engineering 2021年第6期35卷 924-932页

作者： CHEN long NG Kai-Wern School of Hydraulic and Environmental Engineering Changsha University of Science and TechnologyChangsha 410114China Department of Civil Engineering Faculty of EngineeringUniversity of MalayaKuala Lumpur 50603Malaysia Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province Changsha University of Science and TechnologyChangsha 410114China

Hydrokinetic energy is a promising technology to harness predictable renewable energy from free-flowing water,tides and ocean *** studies have been conducted by researchers and engineers to find out ways to enhance the performance of the hydrokinetic *** current paper reports the experimental study of using hydrophobic coating as an alternative way to improve the performance of hydrokinetic turbine.A hydrophobic coating can lower the friction drag of a surface that is in contact with *** hydrokinetic turbine blade,reduction in friction drag may allow a blade section to have a better lift/drag ratio and have its efficiency *** this study,a formula to predict the pattern of drag reduction over a hydrophobic surface has been *** hydrophobic coatings were applied on NACA 63418 hydrofoils and their performances were *** was found that NACA 63418 hydrofoil with the hydrophobic coatings had its drag reduced by an average of 3%−4.0%.When the coatings were applied on a 350 mm diameter three-bladed turbine,the maximum increment of rotational speed of the turbine was found to be 2.5%.The performance of the two coatings aga.nst marine fouling was also *** weight of plate with and without the coatings increased by 10%and 100%,respectively.

关键词： hydrophobic coating hydrokinetic energy marine fouling