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1.
给出了求以秩为n的m×n阶Loewner矩阵Moore-Penrose逆的快速算法,该算法的计算复杂度为O(mn) O(n2)。  相似文献   

2.
给出了求以秩为n的m×n Cauchy型矩阵Moore-Penrose逆的快速算法,该算法的计算复杂度为O(mn) O(n2).  相似文献   

3.
通过构造特殊分块矩阵并研究其三角分解,给出求以秩为n的m×nLoewner型矩阵为系数阵的线性方程组极小范数最小二乘解的快速算法,该算法的计算复杂度为O(mn)+O(n2),而一般方法的计算复杂度为O(mn2)+O(n3).  相似文献   

4.
本文首先给出一个求解一类T型线性方程组的快速串行算法,它的复杂性是O(nlogn),比目前最好的O(n~2)算法复杂性要低。接着又指出了它的并行计算方案,在n台处理机的条件下,计算步数不超过O(logn),速度倍数是O(n),效率是O(1)。  相似文献   

5.
皮军德  林浩 《河南科学》2007,25(4):537-541
研究了广义区间图的最小全控制集和最小配对控制集的计算问题.对有一个公共交点的直线簇上的区间图,给出了计算其最小全控制集的O(n)时间算法和其最小配对控制集的O(n+m)时间算法.  相似文献   

6.
通过构造特殊分块矩阵及其三角分解给出了求秩为n 的m×n阶Loewner型矩阵为系数阵的线性方程组极小范数最小二乘解的快速算法, 该算法的计算复杂度为O(mn)+O(n2), 而一般方法的计算复杂度为O(mn2)+O(n3) .  相似文献   

7.
利用快速傅立叶变换 (FFT) ,给出了 n阶循环矩阵开平方的一个快速算法 ,计算循环矩阵的同型平方根矩阵 (平方根矩阵也是循环矩阵 ) ,证明了同型平方根矩阵的个数为 2 n ,它是关于 n的指数函数 ;计算一个同型平方根矩阵的时间复杂性为 O(nlog2 n) ;计算全部同型平方根矩阵的时间复杂性为 O(n2 n) .  相似文献   

8.
利用了n阶对称Toeplitz-plus-Hankel矩阵的结构特点和对称性,给出了计算该类矩阵所有特征值的一个快速算法.该算法的计算复杂度为O(n2logn),比文献[1-]所给的算法来得少.  相似文献   

9.
对称Loewner矩阵在自然科学及工程技术中有着广泛的应用,许多问题都归结为求对称Loewner矩阵及其相关矩阵的代数问题.论文通过构造特殊分块矩阵并研究其逆矩阵,给出了秩为n的m×n对称Loewner矩阵Moore-Penrose逆的快速算法,该算法的计算复杂度为O(mn)+O(n2),而通过L+=(LTL)-1LT计算的复杂度为O(mn2)+O(n3).实验数据也表明前者在用时和效率方面均优于后者.  相似文献   

10.
本文讨论有限群上几个计算问题。我们设了一个O(n~2)时间的算法去查找n阶Abel群的基底(把n阶Abel群分解为循环P群的直积)。给出了复杂度为O(n~2log_2n)的n阶Abel群的检验算法。证明了n阶Abel群的同构检验可在O(nlOg_2n)时间内完成。最后,我们讨论定义在有限群上的旅行售货员问题:证明了该问题是NP完全的,并给出了一个O(m·n~2·2~n)时间的算法求解它。  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.
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   

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

19.
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   

20.
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   

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