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1.
本文在解不适定算子方程的隐式迭代中引入一个松弛因子ω,得到了松弛隐式迭代法,研究了精确和非精确右端迭代近似解的收敛性态和收敛速率,并得用残差原则给出了可执行的算法,理论推导表明,只要选取适当的松弛因子,迭代的收敛速率优于原先的隐式迭代法。  相似文献   

2.
提出了一种新交替线性隐式迭代法来求解非对称代数黎卡提方程的最小非负解,证明了该算法的单调收敛性,并且估计了该算法的渐进收敛因子.与已有的交替线性化隐式迭代法相比,该算法在迭代次数、CPU时间以及误差3个方面均有一定优势.  相似文献   

3.
提出了求解回流中速度、压力耦合方程组的两组块交替方向隐式迭代的算法。以存在解析解的无粘射流为算例,进行了数值模拟;同时还就计算时间与所需迭代次数将此法与SIMPLE法作了比较。结果表明,使用此法可节省计算机时、提高收敛速率,所得数值解与解析解也相当吻合。讨论了迭代过程中的最佳松弛因子。  相似文献   

4.
求解矩阵方程组AX=C,XB=D的迭代法   总被引:1,自引:1,他引:0  
给出了求解矩阵方程组AX=C,XB=D的迭代法,迭代收敛到它的极小F-范数解,并给出了此极小F-范数解的显式.  相似文献   

5.
提出了湍流κ-ε模型方程迭代求解中自适应松驰方法。该方法能根据迭代求解过程得到一系列最优松驰因子,从而提高收敛求解速度与性能。计算结果表明自适应松驰方法是相当有效的,使湍流求解收敛速度提高了2.5倍。  相似文献   

6.
利用Banach压缩映射原理,证明了高维空间中的一个全局隐函数定理,给出计算隐函数近似解的迭代算法,并证明迭代序列收敛于隐函数的精确解,改进和推广了某些文献中已知的结果。  相似文献   

7.
本文给出了用迭代法解线性方程组μ=1时迭代收敛的一个充分条件.并且用类似的方法给出了v=1时迭代收敛的一个充分条件。  相似文献   

8.
主要研究了双曲方程的三层隐式差分方程的分段并行迭代法。其基本思想是把隐式差分方程组划分为若干个子方程组来分别同时进行求解。文中给出了构造隐式差分方程组的分段隐式迭代法的一般过程,论证了它的收敛性。它具有0(△t^2+△x^2)的精度阶和绝对稳定性对任意网比r和任意阶子方程组迭代过程都是收敛的。并阐明了它处理子方程组的优越性。为说明此迭代法的有效性,针对具体例子给出了数值试验结果。  相似文献   

9.
构造了求解一类隐式互补问题的加速模系矩阵分裂迭代法。理论分析建立了新方法在系数矩阵为H+-矩阵时的收敛性质。数值实验结果表明新方法是行之有效的,并且加速模系矩阵分裂迭代法在迭代步数和时间上均优于传统的模系矩阵分裂迭代法。  相似文献   

10.
针对混合型方程组提出一种新的迭代算法.新算法有如下特点:第一,收敛速度快,同Newton迭代法一样,新算法具有二阶收敛速度; 第二,计算成本低,新算法低于Newton迭代法.在对新算法的收敛性进行严格证明的同时,数值实验还证实,新算法对初始解与精确解的接近程度的要求也比Newton迭代法有所降低.  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.
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   

15.
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   

16.
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   

17.
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   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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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