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1.
分析了感知器算法解空间的几何特性,提出了一种基于解区域的感知器改进算法.若模式线性可分,可在解区域中求得较优解向量;若线性不可分,则指出不存在解区域.实验结果表明,该算法能很快判别模式是否线性可分,并能有效解决算法的收敛性问题,提高了计算速度.  相似文献   

2.
针对解线性调频算法搜索步长减小时运算量增加的情况,提出了基于最小二阶乘方法的快速解线性调频算法.分析了快速算法原理、最终可达到的分析精度及提高分析精度方法.仿真验证表明基于最小二阶乘快速解线性调频算法快速有效.  相似文献   

3.
线性互补问题全部解的求法—整标集法   总被引:5,自引:1,他引:4  
研究线性互补问题解的存在性,发现一例,用Lemke算法找不到解,用特殊方法找到一解,随后提出并证明了线性互补问题的充分必要条件,以此为理论基础结合求求线性互补总是全部解的算法-整标集法,此算法具有一般性,使用范围广泛,用它可以求得线性互补问题的全部欠妥 ,给出3个算例,用3种方法求解,对于其中的每一个,用整标集法都找到了许多解,然而,其中两例用Lemke算法均没有找到解,最后指明了原因。  相似文献   

4.
首先研究了Riccati矩阵方程中变量矩阵为对称矩阵和自反矩阵异类约束解问题,其次采用牛顿算法将Riccati矩阵方程异类约束解转化为线性矩阵方程的异类约束解,最后采用修正共轭梯度算法(MCG)解决了线性矩阵方程异类约束解或者是最小二乘解问题.  相似文献   

5.
讨论了控制理论中二次矩阵方程的约束解问题,结合牛顿算法以及修正共轭梯度算法(MCG),建立了多变量二次矩阵方程异类约束1-3-7解的牛顿-MCG算法.先用牛顿算法把非线性二次矩阵方程转化为关于校正矩阵的线性矩阵方程,再用MCG算法求线性矩阵方程异类约束解或最小二乘约束解,给出了算法性质和结论.最后,用数值算例验证了该算法是有效的.  相似文献   

6.
对一般线性比式和问题(P)提出了一种全局优化算法,此方法利用拉格朗日对偶中的弱对偶定理建立原问题(P)的线性松弛规划,运用分枝定界方法只需解一系列线性问题。从理论上证明了算法能收敛到线性比式和问题的全局最优解。数值计算结果表明提出的方法是可行的。  相似文献   

7.
用线性规划对偶理论讨论了线性双层规划的最优性条件,利用下层问题的对偶间隙,将线性双层规划转化为目标函数带惩罚项的单层问题,通过对转化后的单层问题进行求解,给出了一个求解线性双层规划局部最优解的方法,然后引进一种割平面约束来修正当前局部最优解,直到求得线性双层规划的全局最优解。提出的算法具有全局收敛性,并通过一个算例说明了算法的求解过程。  相似文献   

8.
应用二重网格差分算法处理了一类半线性椭圆问题。无需求细网格上的非线性解,对粗网格(可以很粗)上的数值解在细网格上进行几次线性修正即可,且重复算法的最后一步可以按粗网格步长任意阶地逼近细网格上的非线性解。算法提高了计算效率但不降低精度,有数值算例加以验证。  相似文献   

9.
求解线性多目标规划的一种新方法   总被引:3,自引:0,他引:3  
给出求解线性多目标规划问题弱有效解子集的一种新算 法. 在不同的条件下, 运用此算法得到了线性多目标规划的弱有效解子集, 并在得到的解子 集中再次进行寻优, 进而得到弱有效解集中决策者满意的较优解; 同时用VC++语言实现 了此算法, 并给出了具体算例.  相似文献   

10.
半线性椭圆方程的一个新的双重网格差分算法   总被引:1,自引:0,他引:1  
用所提出的双重网格算法研究了半线性椭圆方程,其对粗网格(可以很粗)的非线性解在细网格上进行了几次线性修正.无需求解细网格上的非线性解,且重复算法最后两步,可使解的误差估计达到任意阶精度,并提出了相应的数值算例.  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.
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   

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 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   

15.
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   

16.
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   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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