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impulsive efects on global stability of models based on impulsive diferential equations with “supremum” and variable impulsive perturbations

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Applied Mathematics and Mechanics(English Edition) 2014年第1期35卷 85-96页

作者： i.M.StAMOVA t.G.StAMOV Department of Mathematics The University of Texas at San Antonio Department of Engineering Design Faculty of Mechanical EngineeringTechnical University of Sofia

Sufficient conditions are investigated for the global stability of the solu tions to models based on nonlinear impulsive differential equations with ＂supremum＂ and variable impulsive perturbations. the main tools are the Lyapunov functions and Razu mikhin technique. two illustrative examples are given to demonstrate the effectiveness of the obtained results.

关键词： global stability Lyapunov-Razumikhin function nonlinear impulsive dif-ferential equation with "supremum" variable impulsive perturbation

Projections of weak braided Hopf algebras

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Science China Mathematics 2011年第5期54卷 877-906页

作者： ALONSO LVAREZ Jos Nicanor FERNNDEZ ViLABOA Jos Manuel GONZLEZ RODRíiguez Ramón SONEiRA CALVO Carlos Departamento de Matemticas Universidad de Vigo Vigo E-36310 Spain Departamento de lxebra Universidad de Santiago de Compostela Santiago de Compostela E-15771 Spain Departamento de Matemtica Aplicada ii Universidad de Vigo Vigo E-36310 Spain Departamento de Matemticas Universidad de Vigo Vigo E-36004 Spain

in this paper we study the projections of weak braided Hopf algebras using the notion of Yetter-Drinfeld module associated with a weak braided Hopf algebra. As a consequence, we complete the study ofthe structure of weak Hopf algebras with a projection in a braiding setting obtaining a categorical equivalencebetween the category of weak Hopf algebra projections associated with a weak Hopf algebra H living in abraided monoidal category and the category of Hopf algebras in the non-strict braided monoidal category ofleft-left Yetter-Drinfeld modules over H.

关键词： weak Yang-Baxter operator Yetter-Drinfeld module weak (braided) Hopf algebra weak Hopf algebra projection

Effect of thermal Refining on Mechanical Properties of Annealed SAE 4130 by Multilayer GtAW

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Journal of iron and Steel Research international 2012年第7期19卷 71-78页

作者： i K Lee C L Chung Y t Lee Y t Chien Department of Materials Science and Engineering Da-Yeh University

During the first welding process in manufacturing a precise seam container, the steel material must first undergo a full annealing treatment. Multilayer welding operations are conducted and then applied with refining treatment to obtain the goal by hardening. the influence of thermal refining on mechanical properties of annealed SAE 4130 by multilayer GtAW （gas tungsten arc welding） was discussed. the AW （annealing＋welding） and AWSt （annealing＋welding＋solution＋tempering） occurred with a minimum hardness value at GGHAZ （grain growth heat affected zone） due to coarse grain growth~ the hardness occurred with sudden drops between the multilayer welding, but was still larger than the minimum value at HAZ （heat affected zone）. the welded joint efficiency of the AWSt was 89.9%, with the elongation reduced to 77.2% of ASt （annealing＋solution＋tempering）. the cross section of the tensile samples both appeared with a uniform dimple-shaped structure, and however the necking for ASt was greater than that for AWSt. the impact value for AWSt was 166.5% of ASt. Moreover, from microstructure observations, it was found that AWSt had a greater tendency to ductile failure than ASt. these results can be inferred., the process of steady pressure and the initial position of the precision tube breakage HAZ. However, when stress occurs instantly, HAZ can absorb more energy, therefore the initial damage does not occur.

关键词： thermal refining SAE 4130 multilayer welding GtAW

A critical review on natural compounds interacting with the plant plasma membrane H^(+)-AtPase and their potential as biologicals in agriculture

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Journal of integrative Plant Biology 2022年第2期64卷 268-286页

作者： Nanna W.Havshφi Anja t.Fuglsang Department of Plant and Environmental Sciences Section for Transport BiologyUniversity of CopenhagenFrederiksbergCopenhagenDK-1871 Denmark

the plant plasma membrane(PM)H^(+)-AtPase is an essential enzyme controlling plant growth and *** is an important factor in response to abiotic and biotic stresses and is subject to tight *** are in demand for new sustainable natural growth regulators and as a key enzyme for regulation of transport into the plant cell the PM H^(+)-AtPase is a potential target for *** this review,we have evaluated the known non-protein natural compounds with regulatory effects on the PM H^(+)-AtPase,focusing on their mechanism of action and their potential as biologicals/growth regulators in plant production of future sustainable agriculture.

关键词： biologicals cyclic-lipodepsipeptides H^(+)-AtPase H+pump natural compounds phosphatidylinositol plasma membrane pore forming compound tenuazonic acid

temperature cycling and its effect on mechanical behaviours of highporosity chalks

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第4期11卷 749-759页

作者： t.Voake A.Nermoen R.i.Korsnes i.L.Fabricius University of Stavanger StavangerNorway the National iOR Centre of Norway University of StavangerStavangerNorway international Research institute of Stavanger (iRiS) StavangerNorway technical University of Denmark (DtU) CopenhagenDenmark

temperature history can have a significant effect on the strength of water-saturated *** this study,hydrostatic stress cycles are applied to understand the mechanical response of chalk samples exposed to temperature cycling between each stress cycle,compared to the samples tested at a constant *** total accumulated strain during a stress cycle and the irreversible strain are *** samples from Kansas (USA) and Mons (Belgium),with different degrees of induration (*** of contact cementation),were *** samples were saturated with equilibrated water (polar) and nonpolar isopar H oil to quantify water *** samples tested during 10 stress cycles with varying temperature (*** cycled in between each stress cycle) accumulated more strain than those tested at constant *** the stress cycles were performed at 30 ℃.the two chalk types behaved similarly when saturated with isopar H oil,but differently when saturated with *** saturated with water,the stronger Kansas chalk accumulated more total strain and more irreversible strain within each stress cycle than the weaker Mons chalk.

关键词： Elastoplastic partitioning Anisotropic thermal expansion Strain accumulation due to temperature and stress cycles

Near resonance vibration isolation on a levered-dual response(LEDAR)Coulomb-damped system by differential preloads/offsets in linear springs

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1033-1050页

作者： t.i.tOLUWALOJU C.K.tHEiN D.HALiM Department of Mechanical Materials and Manufacturing EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100Zhejiang ProvinceChina Nottingham Ningbo China Beacons of Excellence Research and innovation institute University of Nottingham Ningbo ChinaNingbo 315048Zhejiang ProvinceChina

the levered-dual response(LEDAR)Coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear *** takes the advantages of both the preloads/offsets in linear springs and the guiderail friction for realizing different levels of vibration *** isolation capacities are investigated on the strategies with both the horizontal and vertical guiderails,with the horizontal rail only,and without *** compressive preloads generally result in the consumption of most of the initial excitation energy so as to overcome the potential *** isolation onsets at the frequency ratio of 1∓0.095 on the left-hand side(LHS)and the right-hand side(RHS)of the lever are relative to the load plate *** observed near resonant isolation thus makes the LEDAR system a candidate for the isolation of the mechanical systems about resonance while opening a path for simultaneous harvesterisolation functions and passive functions at extreme frequencies.

关键词： lever ratio Coulomb damping preload tension/compression isolation band/depth offset potential

Challenges for beyond 5G:ultra-densification of radio access network

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通信学报 2020年第11期41卷 1-11页

作者： Fumiyuki Adachi Ryo takahashi Hidenori Matsuo Research Organization of Electrical Communication Tohoku UniversitySendai 980-8577Japan

Ultra-densification of radio access network(RAN)is a key to efficiently support the exponentially growing mobile data traffic in 5 G ***,extremely high frequency band like mm Wave band was utilized to solve the bandwidth shortage ***,untra-dense reusing the same radio resource produced severe *** the mm Wave link was very harsh due to frequent blockage by *** a new RAN architecture needed to be introduced to realize ultra-reliable communications in such a severe radio propagation *** architecture of distributed MiMO based RAN was ***,enhanced interference coordination(e iC)was ***,the effectiveness of distributed MiMO based RAN with e iC by computer simulation was showed.

关键词： 5G advanced systems distributed MiMO radio access network interference coordination cooperative signal transmission

Numerical analysis of interaction between solute atom and extended dislocation using force multipoles

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Journal of Central South University 2014年第8期21卷 3000-3006页

作者： Hiroaki Morita Akiyuki takahashi Department of Mechanical Engineering Faculty of Science and TechnologyTokyo University of Science

the interaction between a solute atom and an extended dislocation was investigated using a continuum approximation method with force *** dislocation core structure of extended dislocation was modeled with the Peierls-Nabarro model discretized with a number of infinitesimal Volterra *** interaction energy and force between a nickel solute atom and perfect and extended dislocation in copper were successfully calculated using the force *** results clearly show that the core structure of extended dislocation weakens the interaction with solute *** interaction energy and force for extended dislocations are almost the half of those for perfect dislocations.

关键词： solution hardening force multipole solute atom extended dislocation Peierls-Nabarro model

Recent advances in prostate cancer: WNt signaling, chromatin regulation, and transcriptional coregulators

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Asian Journal of Andrology 2023年第2期25卷 158-165页

作者： Sayuri takahashi ichiro takada Department of Urology The Institute of Medical ScienceThe University of TokyoShirokanedaiMinato-kuTokyo 108-8639Japan Department of Urology The Faculty of MedicineThe University of TokyoHongoBunkyo-kuTokyo 113-8655Japan

Prostate cancer is one of the most common diseases in men ***,radiation therapy,and hormonal therapy are effective treatments for early-stage prostate ***,the development of castration-resistant prostate cancer has increased the mortality rate of prostate *** develop novel drugs for castration-resistant prostate cancer,the molecular mechanisms of prostate cancer progression must be *** the signaling pathways regulating prostate cancer development,recent studies have revealed the importance of noncanonical wingless-type MMtV integration site family(WNt)signaling pathways,mainly that involving WNt5A,in prostate cancer progression and metastasis;however,its role remains ***,chromatin remodelers such as the switch/sucrose nonfermentable(SWi/SNF)complex and chromodomain helicase DNA-binding proteins 1 also play important roles in prostate cancer progression through genome-wide gene expression ***,we review the roles of noncanonical WNt signaling pathways,chromatin remodelers,and epigenetic enzymes in the development and progression of prostate cancer.

关键词： chromatin remodeling histone-modifying enzymes prostate cancer WNt5A