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Effect of Wave Nonlinearity on the Instantaneous Seabed Liquefaction

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china ocean Engineering 2024年第1期38卷 93-103页

作者： WANG Zhao-jun SUI Ti-ti ZHANG chi PAN jun-ning Key Laboratory of Port Waterway and Sedimentation Engineering of the Ministry of TransportNanjing Hydraulic Research InstituteNanjing 210024China Key Laboratory of coastal Disaster and Protection(Hohai University) Ministry of EducationNanjing 210098China The National Key Laboratory of Water Disaster Prevention Nanjing 210098China

The nonlinear variation of wave is commonly seen in nearshore area,and the resulting seabed response and liquefaction are of high concern to coastal *** this study,an analytical formula considering the nonlinear wave skewness and asymmetry is adopted to provide wave pressure on the seabed *** liquefaction depth attenuation coefficient and width growth coefficient are defined to quantitatively characterize the nonlinear effect of wave on seabed *** on the 2D full dynamic model of wave-induced seabed response,a detailed parametric study is carried out in order to evaluate the influence of the nonlinear variation of wave loadings on seabed ***,new empirical prediction formulas are proposed to fast predict the maximum liquefaction under nonlinear *** indicate that(1)Due to the influence of wave nonlinearity,the vertical transmission of negative pore water pressure in the seabed is hindered,and therefore,the amplitude decreases significantly.(2)In general,with the increase of wave nonlinearity,the liquefaction depth of seabed decreases *** under asymmetric and skewed wave loading,the attenuation of maximum seabed liquefaction depth is the most significant among all the nonlinear wave ***,highly skewed wave can cause the liquefaction depth of seabed greater than that under linear wave.(3)The asymmetry of wave pressure leads to the increase of liquefaction width,whereas the influence of skewedness is not significant.(4)compared with the nonlinear waveform,seabed liquefaction is more sensitive to the variation of nonlinear degree of wave loading.

关键词： nonlinear wave seabed response seabed liquefaction numerical simulation liquefaction prediction

Finite-time Sliding Mode control Design for a class of Uncertain conic Nonlinear Systems

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IEEE/cAA Journal of Automatica Sinica 2017年第4期4卷 809-816页

作者： Shuping He jun Song Sc.ool of Electrical Engineering and Automation Anhui UniversityHefei 230601China

This paper studies the sliding mode controller design problems for a class of nonlinear system. The nonlinear function is considered to satisfy conic-type constraint condition. A novel finite-time boundedness(FTB) based sliding mode controller design theory is proposed. And then a sufficient condition is obtained in terms of linear matrix inequalities(LMIs), which guarantees the resulted sliding mode dynamics to be FTB wrt some predefined scalars. Thereafter, a FTB-based sliding mode control(SMc) law is synthesized to ensure the state of the controlled system is driven into a novel desired switching surface s(t) = c(c is a constant) in a finite time. Simulation results illustrate the validity of the proposed FTB-based SMc design theory.

关键词： conic nonlinear system finite-time boundedness(FTB) sliding mode control(SMc) state-feedback

Nuclear Trafficking During Plant Innate Immunity

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Molecular Plant 2008年第3期1卷 411-422页

作者： jun Liu Gitta coaker Department of Plant Pathology The University of California Davis CA USA

Land plants possess innate immune systems that can control resistance against pathogen infection. conceptually, there are two branches of the plant innate immune system. one branch recognizes conserved features of mic.obial pathogens, while a second branch specifically detects the presence of pathogen effec.or proteins by plant resistance （R） genes. Innate immunity controlled by plant R genes is called effec.or-triggered immunity. Although R genes can recognize all classes of plant pathogens, the majority can be grouped into one large family, encoding proteins with a nucleotide binding site and c-terminal leucine rich repeat domains. Despite the importance and number of R genes present in plants, we are just beginning to decipher the signaling events required to initiate defense responses. Recent exciting discoveries have implicated dynamic nuclear trafficking of plant R proteins to achieve effec.or-triggered immunity. Furthermore, there are several additional lines of evidence implicating nucleo-cyc.oplasmic trafficking in plant disease resistance, as mutations in nucleoporins and importins can compromise resistance signaling. Taken together, these data illustrate the importance of nuclear trafficking in the manifestation of disease resistance mediated by R genes.

关键词： DISEASE-RESISTANcE GENES PoWDERY MILDEW FUNGUS PoTATo-VIRUS-X IMPoRTIN-ALPHA DEFENSE RESPoNSE EXPoRT REcEPToR PRoTEIN-KINASES

Phylogeny and putative hybridization in the subtribe Paranepheliinae （Liabeae, Asteraceae）, implications for classification, biogeography, and Andean orogeny

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植物分类学报 2008年第3期46卷 375-390页

作者： Akiko SoEJIMA jun WEN Mario ZAPATA Michael o. DILLoN Sc.ool of Science Osaka Prefecture University Sakai Osaka 599-8531 Japan Department of Botany National Museum of Natural History MR C-166 Smithsonian Institution Washington DC 20013 -7012 USA Museo de Historia Natural Universidad Antenor Orrego Trujillo 1075 Peru Department of Botany The Field Museum Chicago IL 60605 USA

The nuclear ribosomal ITS region and the chloroplast trnL-trnF (trnLF) intergenic region were se-quenced for 45 accessions of Paranephelius and six accessions of Pseudonoseris, the two genera of the subtribe Paranepheliinae (Liabeae, Asteraceae) distributed in the alpine regions of the Andes. This data set was used to estimate relationships between these genera and within each genus to aid in evaluating morphological variation and classification. our results with both ITS and trnLF markers support the monophyly of subtribe Paranephelii-nae, and place Pseudonoseris discolor as the first diverged taxon sister to the clade containing Paranephelius. Pseudonoseris szyszylowiczii exhibited intraspecific divergence supporting intergeneric hybridization between Pseudonoseris and Paranephelius. Within Paranephelius, genetic divergence is low and not adequate to fully resolve phylogenetic relationships at the species level, but two genetically and morphologically recognizable groups were revealed by the ITS data. Several accessions possessing multiple ITS sequences represent putative hybrids between the two groups. These putative hybrids have caused some taxonomic confusion and difficulties in establishing species boundaries in Paranephelius. The divergence time estimates based on ITS sequences indi-cated that the stem of subtribe Paranepheliinae dates to 13 million years ago, but the diversification of the c.own clade of the extant members began in the early Pleistocene or late Pliocene, perhaps associated with the uplift of the Andes and the climatic changes of global c.oling.

关键词：系统演化杂交生物地理学安第斯山脉造山运动

IMPRoVING 9-INTERSEcTIoN MoDEL BY REPLAcING THE coMPLEMENT WITH VoRoNoI REGIoN

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Geo-Spatial Information Science 2000年第1期3卷 1-10页

作者： cHEN jun LI chengming LI Zhilin Gold c M National Geomatics Center of China Beijling China

9-intersection model is the most popular framework used for formalizing the spatial relations between two spatial objectsA andB. It transforms the topological relationships between two simple spatial objectsA andB into point-set topology problem in terms of the intersections ofA’s boundary (?A), interior (A 0) and (A ?) withB’s boundary (?B), interior (B 0) and exterior (B ?). It is shown in this paper that there exist some limitations of the original 9-intersection model due to its definition of an object’s exterior as its complement, and it is difficult to distinguish different disjoint relations and relations between complex objects with holes, difficult or even impossible to compute the intersections with the two object’s complements (?A∩B ?,A 0∩?B ?,A ?∩?B,A ?∩B 0 andA ?∩B ?)since the complements are infinitive. The authors suggest to re-define the exterior of spatial object by replacing the complement with its Voronoi region. A new Voronoi-based 9-intersection (VNI) is proposed and used for formalizing topological relations between spatial bojects. By improving the 9-intersection model, it is now possible to distinguish disjoint relations and to deal with objects with holes. Also it is possible to compute the exterior-based intersections and manipulate spatial relations with the VNI.

关键词： 9-intersection model Voronoi region topological relationship

controllable vortex lasing arrays in a geometrically frustrated exciton-polariton lattice at room temperature

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National Science Review 2023年第1期10卷 196-204页

作者： jun Wang Yutian Peng Huawen Xu Jiangang Feng Yuqing Huang Jinqi Wu Timothy c.H.Liew Qihua Xiong Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University Department of optical Science and Engineering and Shanghai Frontiers Science Research Base of Intelligent Optoelectronics and Perception Fudan University State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics Tsinghua University Beijing Academy of Quantum Information Sciences

Quantized vortices appearing in topological excitations of quantum phase transition play a pivotal role in strongly correlated physics involving the underlying confluence of superfluids,Bose-Einstein condensates and *** polaritons as bosonic quasiparticles have enabled studies of non-e quilibrium quantum gases and ***-polariton condensates in artificial lattices intuitively emulate energy-band structures and quantum many-body effects of condensed matter,underpinning constructing vortex lattices and controlling quantum fluidic ***,we harness exciton-polariton quantum fluids of light in a frustrated kagome lattice based on robust metal-halide perovskite mic.ocavities,to demonstrate vortex lasing arrays and modulate their configurations at room *** energy-momentum spectra unambiguously reveal massless Dirac bands and quenched kinetic-energy flat bands coexisting in kagome lattices,where polariton condensates exhibit prototypical honeycomb and kagome spatial *** coherence investigations illustrate two types of phase textures of polariton condensates carrying ordered quantized-vortex arrays and π-phase shifts,which could be selected when needed using lasing emission *** findings offer a promising platform on which it is possible to study quantum-fluid correlations in complex polaritonic lattices and highlight feasible applications of structured light.

关键词： vortex lasing exciton–polariton lattice Bose–Einstein condensation the orbital angular momentum of light geometric frustration perovskite semiconduc.or

定向电场下W_(6)c_(6)团簇的超卤素调制及非线性光学特性

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原子与分子物理学报 2025年第3期42卷 72-76页

作者：蔡璧钧段宇静魏强重庆理工大学理学院重庆400050

本文采用密度泛函(DFT)方法研究了定向外电场(oEEF)对W_(6)c_(6)团簇几何结构、电子性质以及非线性光学响应(NLo)的影响.计算结果表明W_(6)c_(6)的结构在一定oEEF强度下可以保持稳定.oEEF可以增大W_(6)c_(6)团簇的电子亲和能(EA值),且... 详细信息

本文采用密度泛函(DFT)方法研究了定向外电场(oEEF)对W_(6)c_(6)团簇几何结构、电子性质以及非线性光学响应(NLo)的影响.计算结果表明W_(6)c_(6)的结构在一定oEEF强度下可以保持稳定.oEEF可以增大W_(6)c_(6)团簇的电子亲和能(EA值),且在特定强度下,oEEF可以将W_(6)c_(6)团簇转变为超卤素.通过对EA值的非线性拟合可以实现对W_(6)c_(6)团簇的连续调制.进一步对不同外电场下W_(6)c_(6)团簇的最高占据分子轨道(HoMo)和最低未占据分子轨道(LUMo)能级进行分析,发现oEEF降低了W_(6)c_(6)团簇LUMo能级是其EA值增大的主因.此外,oEEF可以显著增大W_(6)c_(6)团簇的平均极化率和第一超极化率,尤其是第一超极化率,改变其非线性光学性质.

关键词：定向外电场超原子密度泛函理论 NLo W_(6)c_(6)团簇

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The slip rate and strong earthquake recur-rence interval on the Qianning-Kangding segment of the Xianshuihe fault zone

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Acta Seismologica Sinica(English Edition) 2001年第3期14卷 263-273页

作者： ZHoU Rong-jun Seismological Bureau of Sichuan Province Chengdu China

The geometry of the Qianning-Kangding segment of the Xianshuihe fault zone is quite complex, and it is composed of four secondary-faults, i.e., the Yalahe fault, Selaha-Kangding fault, Zeduotang fault and Moxi fault. on this segment, three strong earthquakes with M greater than or equal 7.0 occurred in 1725, 1786 and 1955, respectively. Based on a study of fault landform and geochronology (14c and Thermoluminesense), this paper documents the average horizontal slip rates during the late-Quaternary on all the secondary-faults of the Qianning-Kangding segment as follows: Yalahe fault: (2.0±0.2) mm/a; Selaha-Kangding fault: (5.5±0.6) mm/a; Zeduotang fault: (3.6±0.3) mm/a; Moxi fault: (9.9±0.6) mm/a. The results from the investigation of surface ruptures of historical earthquakes, coseismic-slip and paleo-earthquakes show that the strong-earthquake recurrence intervals are thousands of years on the Yalahe fault, and 230 to 350 years on the Selaha-Kangding and Zeduotang faults. In the next one hundred years, the recurrence of a strong-earthquake on these faults appears impossible. However, the strong-earthquake recurrence interval on the Moxi fault is about 300 years. Up to now, it has been 214 years since the last earthquake (magnitude 7 3/4) occurred in 1786, therefore, this fault is now approaching the condition favorable for the next strong earthquake recurrence.

关键词： Fault landform Paleo-earthquake Recurrence interval Seismic potential Slip rate

Proton Irradiation Effects on the Structural and Tribological Properties of Polytetrafluoroethylene

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chinese Journal of Polymer Science 2016年第12期34卷 1448-1455页

作者：刘百幸 jun Liang Zhen-jun Peng Xiang-li Wang State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of Sciences Key Laboratory for Electronic Materials of the State Ethnic Affairs commission College of Electric EngineeringNorthwest University for Nationalities

Polytetrafluoroethylene （PTFE） was irradiated with protons in a ground-based simulation facility to study the effects of proton irradiation on the structural and tribological properties of PTFE. The structural changes were characterized by X-ray photoelectron spectroscopy （XPS） and attenuated total-reflection FTIR （ATR-FTIR）, while the tribological properties were evaluated by friction and wear tests. It was found that proton irradiation induced the degradation of PTFE molecular chains, resulting in the increase of c concentration and the decrease in F concentration on the sample surfaces, and the surface chemical structure and morphology of the samples changed, which affected the friction coefficient and decreased the wear rate of the specimens as the friction and wear tests revealed.

关键词： Polytetrafluoroethylene Proton irradiation Degradation Friction and wear.