一类带有阻尼项的共振问题的周期解

文章主要目的是研究一类带有阻尼项q(t)ù(t)的共振问题ü(t)+q(t)(u·)(t)-A(t)u(t)+▽F(t,u(t))=0 u(0)-u(T)=(u·)(0)-eQ(T)(u·)(T)=0的周期解的存在性。在F满足假设(A)及四个新的存在性条件下,通过使用临界点理论中的极大极小方法获得了一个新的存在性定理。     

用最小作用原理研究具有次线性的非线性项2阶系统

利用最小作用原理研究2阶系统ü(t)-A(t)u(t)=▽F(t,u(t)),a.e.t∈[0,T]u(0)-u(T)=(u)(0)-(u)(T)=0,的周期解的存在性,在非线性项是次线性及A(t)是1个连续N阶对称矩阵的条件下得到了该系统的2个新的存在性定理.     

一类二阶非Hamihonian系统的变分原理及周期解的存在性定理

研究了阻尼振动问题{ü(t)+g(t)(u)(t)=(△)F(t,u(t)),a.e.t∈[O,T];u(0)-u(T)=(u)(0)-(u)(T)=0.其中,T>0,g(t)∈L∞(0,T;R),G(t)=∫t0g(s)ds,G(T)=0,F:[0,T]×RN→R.给出了其变分原理和2个周期解的存在性定理.即使在g(t)=0特殊情况下,所得结果也是新的.     

一类分数阶边值问题解的存在性

运用极小作用原理和鞍点定理,通过引入一类控制函数,考虑如下带Dirichlet边值条件的分数阶微分系统:﹛-d/(dt)(1/2)_0D_t~(-β)(u′(t))+(1/2)_tD_T~(-β)(u′(t()))=▽F(t,u(t)),a.e.t∈[0,T],u(0)=0,u(T)=0,得到了上述问题解的存在性.     

一类二阶超二次哈密顿系统的周期解

研究具有超二次势能的二阶Hamilton系统 {ü+A(t)u(t)+(Δ)F(t,u(t))=0,u(0)-u(T)=(u)(0)-(u)(T)=0 周期解的存在性问题.在线性项非零的假设下,当位势函数F满足新的超二次条件而不满足(A-R)条件时,运用临界点理论中一般的山路引理证明此系统存在非平凡的周期解.推广了已有关于超二次Hamilton系统周期解的存在性结果.     

一阶微分方程周期边值问题最优正解的存在性

利用更一般的锥不动点定理及格林函数的正性,给出了一类一阶微分方程周期边值问题(u)(t) a(t)u(t)=f(t,u(t)),u(0)=u(T)新的最优正解的存在性条件及多重正解存在性条件.     

一类分数阶边值问题解的存在性

研究一类非齐次分数阶微分方程边值问题{-d/dt(1/2_0D_t~(-β)(u′(t))+1/2_tD_T~(-β)(u′(t)))=λh(t)+▽F(t,u(t)),a.e.t∈[0,T],u(0)=0,u(T)=0,烅烄烆其中,λ0,h∈L~2([0,T],R~N)且h(t)■0.利用山路引理和Ekeland变分原理,得到上述问题至少存在2个非平凡解.     

非自治二阶系统周期解的存在性

这篇文章的目的是研究非自治二阶系统¨u(t)=F(t,u(t)),a.e.t∈[0,T]u(0)-u(T)=u(0)-u(T)=0周期解的存在性,通过最小作用原理获得一些存在性定理。     

时标上非线性特征值问题正解的存在性和多解性（英文）

讨论时标T上非线性特征值问题{-u~(ΔΔ)(t)+q(t)u~σ(t)=λf(u~σ(t)),t∈T,u(0)=u(1)=0,其中λ是正参数.运用全局分歧理论,研究在一定条件下上述特征值问题发自u=0和(或)u=∞非零解的连通分支,得到此特征值问题正解的存在性和多解性结果,推广和改进了一些已有结果.     

利用鞍点定理研究一类共振问题的周期解

二阶系统广泛存在于数理科学、生命科学以及社会科学的整个领域,特别是天体力学、航天科学以及生物工程中的很多模型都以二阶系统形式出现.研究以下二阶系统u¨(t)+q(t)u·(t)-A(t)u(t)+F(t,u(t))=0,a.e.t∈[0,T],u(0)-u(T)=u·(0)-eG(T)u·(T)={0的周期解的存在性.含有阻尼项q(t)u·(t)的二阶系统在物理上称为共振问题,因此对该系统的研究具有重要的物理意义.在F(t,x)满足某些新的存在性条件下,通过使用临界点理论中的鞍点定理获得了一个新的存在性定理.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

正~~     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to