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1.
在波Sobolev空间中,利用线性方程的估计和压缩映射原理,得到了广义双耗散方程的低正则局部解。  相似文献   

2.
1.引言 A. Douglis在工作[1]中研究了形如的一阶拟线性方程,对于该方程的广义解建立了顺序原理,利用此顺序原理立即得出柯西问题广义解的唯一性,并且可以导出广义解的构造,可见顺序原理是研究一阶拟线性方程广义解的一个重要工具。本文将从另一途径对一般形式的拟线性方程的广义解建立起相类似的顺序原理。在顺序原理中,我们所考察的广义解属于有界的分块光滑函数类,其中的函数在任何有限区域内除了有限条曲线与有限个点以外为连续可微。这种广义解对于任何在上半平面  相似文献   

3.
本文从状态空间方法出发,吸取频域法的优点,导出线性多变量系统的一般分解模式,并研究了系统结构。为多变量系统的电子计算机模拟及控制提供一个普遍的方便的途径。  相似文献   

4.
进一步研究向量线性方程组的性质,首先利用广义逆矩阵给出了解的一般形式,以及利用逆矩阵给出克兰姆法则另一种证明方法,然后讨论方程组的基础解系与解空间的直和。  相似文献   

5.
利用简化齐次平衡方法,导出了从一个线性方程的解到变形Boussinesq方程组的解之间的非线性变换。借助于线性方程的解及非线性变换,求出了变形Boussinesq方程组的多重孤波解、有理函数解及关于空间变量的周期解等。  相似文献   

6.
一类四阶半线性方程的渐近解   总被引:2,自引:2,他引:0  
在Sobolev空间给出了一类四阶半线性方程初值问题解的一个渐近方法,证明了渐近理论及形式近似解的合理性在时间变量无穷大时(即0≤t≤0(|ε|^-1))成立.作为渐近理论的应用,对一个带初值问题的特殊四阶半线性方程进行了探讨.  相似文献   

7.
研究了一类广义非线性Duffing方程概周期解的存在性。通过Lyapunov函数建立辅助线性方程的指数型二分性,在此基础上,选取适当的函数空间,利用不动点定理,得到广义非线性Duffing有界解的存在性,再次利用Lyapunov函数,得到其概周期解的存在性和模包含关系。  相似文献   

8.
研究多变量向量值双正交多小波包的构造与性质.引进了向量值多分辨分析与多变量值双正交多重小波的概念.给出多变量多重向量值双正交小波包的定义及其迭代方法.运用积分变换与有限群理论,讨论了多变量多重向量值双正交小波包的性质,得到了多变量多重向量值双正交小波包的双正交公式,进而给出多变量向量值函数空间L2(Rs,Cn)的一个新的基底.  相似文献   

9.
将[1]中欧氏空间上多目标优化问题的Hartley真有效解,广义KT-真有效解,广义K-真有效解的概念推广到一般赋范空间上的几量极大值问题(VMP)的情形,在赋范空间的框架下,讨论了[2]中的(VMP)的Borwein真有效解与本文中定义的Hartley真有效解的关系,并建立了广义KT-真有效解的必要条件与充分条件,最后还讨论了(VMP)的Hartley真有效解,广义KT-真有效解,广义K-真有效解的关系,从而推广了[1]中的主要结果。  相似文献   

10.
本文通过薄板问题混合能变分原理,选用状态变量及其对偶变量,导出了一般的Hamilton型广义变分原理和Hamilton正则方程,这样就突破了欧几里德空间的限制,在Hamilton力学的数学框架辛几何空间中,对全状态相变量进行分离变量,并采用共轭辛正交归一关系,给出任意支承条件下薄板问题的辛精确解.  相似文献   

11.
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.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

15.
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.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
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。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
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.  相似文献   

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