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Ocean-Atmosphere Interaction in the Lifecycle of ENSO:The Coupled Wave Oscillator

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Chinese Annals of Mathematics,Series B 2009年第6期30卷 715-728页

作者： Jialin LIN Dedicated to Professor Andrew Majda on the Occasion of his 60th Birthday

To explain the oscillatory nature of E1 Nino/Southern Oscillation （ENSO）, many ENSO theories emphasize the free oceanic equatorial waves propagating/reflecting within the Pacific Ocean, or the discharge/recharge of Pacific-basin-averaged ocean heat content. ENSO signals in the Indian and Atlantic oceans are often considered as remote response to the Pacific SST anomaly through atmospheric teleconnections. This study investigates the ENSO life cycle near the equator using long-term observational datasets. Space-time spectral analysis is used to identify and isolate the dominant interannual oceanic and atmospheric wave modes associated with ENSO. Nino3 SST anomaly is utilized as the ENSO index, and lag-correlation/regression are used to construct the composite ENSO life cycle. The propagation, structure and feedback mechanisms of the dominant wave modes are studied in detail. The results show that the dominant oceanic equatorial wave modes associated with ENSO are not free waves, but are two ocean-atmosphere coupled waves including a coupled Kelvin wave and waves are not confined only to the Pacific a coupled equatorial Rossby （ER） wave. These Ocean, but are of planetary scale with zonal wavenumbers 1-2, and propagate all the way around the equator in more than three years, leading to the longer than 3-year period of ENSO. When passing the continents, they become uncoupled atmospheric waves. The coupled Kelvin wave has larger variance than the coupled ER wave, making the total signals dominated by eastward propagation. Surface zonal wind stress （x） acts to slow down the waves. The two coupled waves interact with each other through boundary reflection and superposition, and they also interact with an off-equatorial Rossby wave in north Pacific along 15N through boundary reflection and wind stress forcing. The precipitation anomalies of the two coupled waves meet in the eastern Pacific shortly after the SST maximum of ENSO and excite a dry atmospheric Kelvin wave which

关键词： ENSO Ocean-atmosphere interaction Equatorial waves

Partial Collapsing Degeneration of Floer Trajectories and Adiabatic Gluing

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Acta Mathematica Sinica,English Series 2024年第1期40卷 161-249页

作者： Yong-Geun oh Ke ZHU Center for Geometry and Physics Institute for Basic Science(IBS)79 Jigok-ro 127beon-gilNam-guPohang-siGyeongsangbuk-doKorea 37673&POSTECHGyeongsangbuk doKorea department of Mathematics and Statistics Minnesota State UniversityMankatoMN 56001USA

In the present paper,we study partial collapsing degeneration of Hamiltonian-perturbed Floer trajectories for an adiabatic ε-family and its reversal adiabatic gluing,as the prototype of the partial collapsing degeneration of 2-dimensional(perturbed)J-holomorphic maps to 1-dimensional gradient *** consider the case when the Floer equations are S^(1)-invariant on parts of their domains whose adiabatic limit has positive length as ε→0,which we call thimble-flow-thimble *** main gluing theorem we prove also applies to the case with Lagrangian boundaries such as in the problem of recovering holomorphic disks out of pearly *** particular,our gluing theorem gives rise to a new direct proof of the chain isomorphism property between the Morse-Bott version of Lagrangian intersection Floer complex of L by Fukaya-oh-ohta-Ono and the pearly complex of L Lalonde and *** also provides another proof of the present authors’earlier proof of the isomorphism property of the PSS map without involving the target rescaling and the scale-dependent gluing.

关键词： Floer trajectory equation partial collapsing degeneration thimble-flow-thimble moduli space adiabatic gluing exponential decay estimates three-interval method

A restudy of Oryctocephalus indicus (Reed,1910)

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Progress in Natural science:Materials International 2006年第11期16卷 1177-1182页

作者： ZHAO Yuanlong~1**, YUAN Jinliang~2, PENG Shanchi~ 2,3 , YANG Xinglian~1, PENG Jin~1, LIN Jihpai~4. and GUO Qingjun~5(1. College of Resource and Environment of Guizhou university, Guiyang 550003, China 2. Nanjing Institute of Geology and Palaeontology, Chinese Academy of sciences, Nanjing 210008, China 3. state Key Laboratory of Papaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Nanjing 210008, China 4. department of geological science,{4., columbus, oh 43.10, usa 5. Institute of Geochemistry, Chinese Academy of sciences, Guiyang 550002, China) College of Resource and Environment of Guizhou university Guiyang 550003 China

Restudy on morphology of Oryctocephalus indicus (Reed, 1910), based on specimens from Guizhou, China and Nevada usa, suggests that the subspecies regarded previously as Oryctocephalus indicus indicus (Reed, 1910), O. indicus latus Zhao et Yuan 2002, and O. indicus kobayashi Saito, 1934. are synonymous, and Oryctocephalus americanus Sundberg et McCollum, 2003 is a similar form of O. indicus. Oryctocephalus indicus is rediagnosed as having a glabella that is subconical in outline and tapering forward slightly; a thorax that comprises 12 segments, and a small pygidium that bears 2—3 axial rings with a terminal piece and a postaxial ridge. Oryctocephalus indicus is widely distributed in eastern Guizhou and ranges through a great interval of Kaili Formation. Its first appearance is almost identical with these events of trilobite extinction-recovery occurring at the end of the Early Cambrian, the alternation of acritach assemblages, the change of trace elements (REE) and stable isotopes (carbon) at the Wuliu-Zengjiaya section. As one of the key forms for defining the traditional Lower-Middle Cambrian boundary (the base of Cambrian Series 3 and Stage 5 in the new Cambrian chronstratigraphic standard), O. indicus has received detailed study and has more advantages than other species such as Ovatoryctocara granulata Tchernysheva, 1962 or Arthricocephalus chauveaui Bergeron, 1899.

关键词： Oryctocephalus indicus restudy Kaili Formation Cambrian Guizhou China.

On hypothesis testing with a partitioned random alternative

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science China Mathematics 2010年第4期53卷 927-938页

作者： WANG WeiZhen department of Mathematics and Statistics,Wright state university,Dayton,oh 4.4.5,usa department of Mathematics and Statistics Wright State University

It is common in statistical practice that one needs to make a choice among m + 1 mutually exclusive claims on *** m=1,it is done by the (traditional) hypothesis *** this paper,a generalization to the case m > 1 is *** fundamental difference with the case m=1 is that the new alternative hypothesis is a partition of m multiple claims and is *** is used to decide which claim in the partition is to be tested as the ***,a random alternative is *** conditional and overall type I errors of the proposed test are controlled at a given level,and this test can be used as a new solution for the general multiple test *** classical problems,including the one-sample problem,model selection in multiple linear regression,and multi-factor analysis,are revisited,and new tests are provided ***,the famous two-sided t-test should be replaced by the proposed.

关键词： analysis of variance conditional probability multiple linear regression one-sample problem

同位素地质年代学及在地质学中的应用(英文)

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地学前缘 1998年第1期5卷 17-39页

作者： Gunter Faure(department of geological sciences, The ohio state university,{4., ohio, usa, 43.10) The ohio state university 美国

一些元素（Ｋ，Ｒｂ，Ｒｅ，Ｓｍ，Ｌｕ，Ｕ和Ｔｈ）的自然长寿命放射性同位素，衰变为另种元素稳定同位素的作用，广泛应用于岩石和矿物的年龄测定。这种测年提供了关于地球地质历史的信息，并已用于标定地质年代表。同位素测年的物理... 详细信息

一些元素（Ｋ，Ｒｂ，Ｒｅ，Ｓｍ，Ｌｕ，Ｕ和Ｔｈ）的自然长寿命放射性同位素，衰变为另种元素稳定同位素的作用，广泛应用于岩石和矿物的年龄测定。这种测年提供了关于地球地质历史的信息，并已用于标定地质年代表。同位素测年的物理原理并不难理解，但所需要的测定技术，则要求同位素地球化学家利用地质人员采集的样品进行熟练精细的操作。对测年结果的解释也应由双方合作进行，并且在很大程度上依靠区域和地区的地质信息。笔者只介绍最广泛应用于测定岩浆岩和变质岩年龄的同位素方法，其余的一些方法只一提而过。

关键词：同位素地质年代学衰变定律地质学铷锶

Artificial Neural Network for Combining Forecasts

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Journal of Systems Engineering and Electronics 1995年第2期6卷 58-64页

作者： Shanming Shi, Li D. Xu & Bao Liu(department of Computer science, university of Colorado at Boulder, Boulder, CO 80309, usa)(department of MSIS, Wright state university, Dayton, oh 4.4.5,usa)(Institute of Systems Engineering, Tianjin university, Tianjin 30 department of Computer science University of Colorado at Boulder CO 80309 USA department of MSIS Wright State University Dayton OH 45435 USA Institute of Systems Engineering Tianjin University Tianjin 300072 China

This paper proposes artificial neural networks (ANN) as a tool for nonlinear combination of forecasts. In this study, three forecasting models are used for individual forecasts, and then two linear combining methods are used to compare with the ANN combining method. The comparative experiment using real--world data shows that the prediction by the ANN method outperforms those by linear combining methods. The paper suggests that the ANN combining method can be used as- an alternative to conventional linear combining methods to achieve greater forecasting accuracy.

关键词： Artificial neural network,Forecasting Combined forecasts Nonlinear systems.

Polynomials,Higher Order Sobolev Extension Theorems and Interpolation Inequalities on Weighted Folland-Stein Spaces on Stratified Groups

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Acta Mathematica Sinica,English Series 2000年第3期16卷 405-444页

作者： Guozhen Lu department of Mathematics,Wayne state university,Detroit,MI 4.202,usa department of Mathematics Wayne State University Detroit USA

This paper consists of three main *** of them is to develop local and global Sobolev interpolation inequalities of any higher order for the nonisotropic Sobolev spaces on stratified nilpotent Lie *** the extensive research after Jerison’s work[3]on Poincaré-type inequalities for Hrmander’s vector fields over the years,our results given here even in the nonweighted case appear to be *** interpolation inequalities have crucial applications to subelliptic or parabolic PDE’s involving vector *** main tools to prove such inequalities are approximating the Sobolev func- tions by polynomials associated with the left invariant vector fields on *** very useful properties for polynomials associated with the functions are given here and they appear to have independent interests in their own *** the existence of such polynomials is the second main part of this *** results of these two parts have been announced in the author’s paper in Mathematical Research Letters[38]. The third main part of this paper contains extension theorems on anisotropic Sobolev spaces on stratified groups and their applications to proving Sobolev interpolation inequalities on(εδ)domains. Some results of weighted Sobolev spaces are also given *** construct a linear extension operator which is bounded on different Sobolev spaces *** particular,we are able to construct a bounded linear extension operator such that the derivatives of the extended function can be controlled by the same order of derivatives of the given Sobolev *** are stated and proved for weighted anisotropic Sobolev spaces on stratified groups.

关键词： Poincaré inequalities Extension theorems Interpolation inequalities Anisotropic Sobolev spaces A_p weights (ε,δ)domains Vector fields Polynomials on stratified groups

Observations on the Efficacy of Various Forms of Selenium for Livestock: A Review

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Biomedical and Environmental sciences 1997年第2期10卷 280-291页

作者： J. E. OLDFIELD (department or Animal science, Oregon state university,Corvallis, OR 97331,{4.) department of Animal science Oregon State University Corvallis 97331 USA.

Since 1957, selenium has found extensive use in livestock production to maintain an adequate selenium status in animals in areas of soil and feed/forage deficiency. Selenium may be given directly to livestock, or applied as a fertilizer amendment to increase selenium content of their feeds. This paper addresses the area of direct supplementation, which includes oral and parenteral supplementation, and with ruminant animals the use of slow-release boluses. Various chemical forms of selenium have been examined as supplemental sources, with sodium selenite being the earliest compound of choice. Comnbination of selenium supplementation with other livestock managernent practices led to use of selenium dioxide, which avoided solubility problems with selenite but produced effective responses. Barium salts have been used with some success as supplemental selenium sources. Experience with ruminal boluses has shown that high pressure pelleting of increased grain size selenium, in hollow pellets, has prolonged their useful life. Attention has been paid recently to residual selenium returned to the soil from livestock supplementation practices and the resulting opinion is that currently approved practices are acceptable from the point of view of environmental quality

关键词： A Review Observations on the Efficacy of Various Forms of Selenium for Livestock

REACTION MECHANISM OF BENZOPHENONE-PHOTOINITIATED CROSSLINKING OF POLYETHYLENE

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Chinese Journal of Polymer science 2002年第4期20卷 291-307页

作者： Bao-jun Qu state Key Laboratory of Fire science and department of Polymer science and Engineering {4. of science and Technology of China Hefei 230026 China university of science and Technology of China State Key Laboratory of Fire Science and Department of Polymer Science and Engineering Hefei 230026

The radical intermediates, the crosslink microstructures, and the reaction mechanism of benzophenone (BP)-photoinitiated crosslinking of low-density polyethylene (LDPE) and model compounds (MD) have been reviewed in detail. The spin-trapping electron spin resonance (ESR) spectra obtained from the LDPE/BP systems with spin-trap agents show that two kinds of polymer radical intermediates are mainly formed: tertiary carbon and secondary carbon radicals. The spin-trapping ESR studies of MD/BP systems give further evidence that photocrosslinking reactions of PE predominantly take place a sites of tertiary carbon, secondary carbon, and especially allylic carbon when available. The high resolution C-13-NMR spectra obtained from LDPE and MD systems show that the crosslink microstructures have H- and Y-type links and that their concentrations are of the same order. The fluorescence, ESR, C-13 and H-1-NMR spectra from the PE and MD systems demonstrate that the main photoreduction product of BP (PPB) is benzpinacol formed by the recombination of two diphenylhydroxymethyl (K-.) radical intermediates. Two new PPB products: an isomer of benzpinacol with quinoid structure, 1-phenylhydroxymethylene-4.diphenylhydroxymethyl-2,5-cyclobexadiene and three kinds of alpha-alkyl-benzhydrols have been detected and identified. These results provide new experimental evidence for elucidating the reaction mechanism in the BP-photoinitiated crosslinking of polyethylene.

关键词： photocrosslinking mechanism polymer radical intermediates crosslink microstructures photolytic products of benzophenone polyethylene model compound