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1.
研究了一类含ζ核的奇异积分-微分方程.利用推广的Plemelj公式构造出一阶微分方程,通过求解该方程直接得出此类奇异积分-微分方程的解,从而给出了这样一类复杂方程的直接解法及其可解条件.  相似文献   

2.
在常利率环境条件下研究在带扰动的广义Erlang(n)风险过程中保险公司的Gerber-Shiu函数问题。在障碍策略下,得出其矩母函数所满足的积分-微分方程及方程的边界条件和Gerber-Shiu函数所满足的积分-微分方程及方程的边界条件。  相似文献   

3.
考虑了带干扰的Erlang(2)风险模型罚金函数的期望,利用建立的积分-微分方程,得出了期望的明确表达式.  相似文献   

4.
主要研究了一类马氏环境下双界限分红模型.不仅考虑了随机环境对保险公司的影响,而且考虑了保险公司为吸引新的顾客,采用分红策略.首先针对破产前红利折现的期望与红利折现的高阶矩得出它们分别满足的积分-微分方程组及其边界条件.其次采用Laplace-变换的方法,得到了此积分-微分方程组的解.  相似文献   

5.
建立和研究了不含消沉项而仅具有纯粹的破损过程的积分-偏微分方程(群体平衡方程)模型.首先采用伸缩变换群分析方法找到了积分-偏微分方程所接受的伸缩变换群及对称,并将积分-偏微分方程转化为纯偏微分方程,利用经典的李群分析方法获得了纯偏微分方程所接受的李群及对称.然后综合伸缩变换群和经典的李群分析方法获得的结果,找到了原积分-偏微分方程所接受的对称、群不变解和约化的积分-常微分方程.最后利用观察试凑函数法发现了约化的积分-常微分方程的精确解,进而给出了原积分-偏微分方程的显式精确解和种群粒子的累积质量及密度分布函数.  相似文献   

6.
考虑了一类带干扰的双险种相关风险模型,利用随机过程的方法得出了该模型的生存概率所满足的积分-微分方程和破产概率的上界.  相似文献   

7.
研究一类细胞分裂群体平衡方程(积分-偏微分方程)的对称群、约化积分-常微分方程、群不变解、显式精确解及解的动力学行为.首先,把积分-偏微分方程转化成纯偏微分方程,然后利用经典李群分析方法计算纯偏微分方程的对称群.其次,采用改进了的李群分析方法结合经典李群分析方法获得的结果确认积分-偏微分方程的对称群.最后,找到积分-偏微分方程的对称群、约化积分-常微分方程、群不变解、显式精确解.运用矩方法获得细胞质量分布的零阶矩和一阶矩,分析了精确解的动力学行为及特征.  相似文献   

8.
在常利率环境条件下研究带扰动的广义Erlang(n)风险过程中保险公司的红利问题.在障碍策略下,得出其矩母函数所满足的积分-微分方程及方程的边界条件和红利所满足的积分-微分方程及方程的边界条件.最后,给出V1(u,b)的表达式并进行数值分析.  相似文献   

9.
考虑一类常利率下带随机干扰的风险模型, 其中保费收取为时间 t 的线性函数而索赔过程为复合Poisson-Geometric 过程. 利用盈余过程的强马氏性、全期望公式及Ito 积分公式得到期望折现罚金函数的积分-微分方程,进一步得到破产概率的积分-微分方程及其在索赔为指数分布情形下的特殊形式, 同时还得出破产时赤字的概率分布.  相似文献   

10.
讨论了一类非线性中立型变延迟积分微分方程的稳定性.针对非线性中立型变延迟积分微分方程的模型方程,给出方程理论解稳定的条件并给予了证明;其次研究了线性θ-方法求解方程的数值稳定性,证明了A-稳定的θ-方法求解非线性中立型变延迟积分微分方程是稳定的.  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 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   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
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。  相似文献   

18.
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.  相似文献   

19.
20.
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  相似文献   

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