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1.
在几何分布模型下,给出了动物总数N的点估计、区间估计,并讨论了N的假设检验问题.当N有先验信息时,得到了N的Bayes推断方法.  相似文献   

2.
单个气体分子的速率是偶然的,但大量气体分子的速率分布是有规律的。在速律在V到V+ΔV之间的的分子数ΔN占总数的N的百分率ΔN/N是确定的。本文用概率统计方法给出了这一结论的简单证明。  相似文献   

3.
单个气体分子的速率是偶然的,但大量气体分子的速率分布是有规律的.速律在V到V+ΔV之间的分子数ΔN占总数N的百分率ΔN/N是确定的.本文用概率统计方法给出了这一结论的简单证明  相似文献   

4.
动物能量密度(能值)分布规律的研究   总被引:1,自引:0,他引:1  
为了考察动物能量密度的分布规律,考虑到目前动物能量密度研究多限于陆生动物,补充测定了72种常见水生无脊椎动物的能量密度,对近230种动物的能量密度的分布规律进行了分析研究,并经Kolmogorov-smimo检验,首次证实了动物能量密度分布规律为正态分布。  相似文献   

5.
推广了高维分布的正态性由低维分布检验问题的有关结论,得到一簇任意N(1<N<n)维子向量服从正态分布而本身非正态的n维分布密度;并给出判定n维正态分布的一个充分条件。  相似文献   

6.
注入离子分布参数的拟合研究   总被引:2,自引:0,他引:2  
N注入Gap中深度分布已被SIMS和^14N(D,a)^12C核反应测出,可用拟合程序拟合出在不同注入条件下N的分布参数,其分布参数是用皮尔逊IV型分布曲线拟合的。拟合出的参数同TR1M89程序和邵其均等人的计算结果作了比较,拟合结果与计算结果是一致的。  相似文献   

7.
讨论了一个延迟Poisson冲击模型以产生NBU-「t0,∞)寿命分布,这个结果是对Poisson冲击产生NBU分布的推广;研究了NBU-「t0,∞)寿命分布已有寿命分布类NBU和NBU-t0的关系,利用灾难变换证明了它在协同结构下的封闭性,同时证明NBU-「t0,∞)与NBU寿命分布的卷积仍然具有NBU-「t0,∞)的性质。  相似文献   

8.
本文在量子化学从头计算的基础上,通过对NO和NO+中电荷密度的分布以及NO分子中原子核与电子间静电引力的分析,得出NO→NO+过程包含有一个非常明显的电荷的重排.关键词  相似文献   

9.
当正态总体的方差未知时,人们常用t检验法来检验总体的均值.事实上,这种检验方法并不一定要求总体是正态分布,甚至样本之间的独立性要求也不是必要的.本文的目的是研究t检验的适用范围,给出了二维随机向量构成服从t分布统计量的充要条件.出于类似的目的,还给出了二维随机向量构成服从Dirichlet分布及F分布统计量的充要条件.  相似文献   

10.
论述了利用三参数威布尔分布描述机械零件疲劳寿命,并在一定置信度下求R─S─N曲线的方法。即根据试验所得的应力─寿命样本,运用优化方法对三多数威布尔分布参数进行估计;并在一定置信度下,求出不同可靠度的疲劳寿命,进而拟合出C─R─S─N曲线,求出相应的疲劳极限应力值。  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.
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   

18.
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   

19.
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   

20.
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   

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