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21.
Existence of $\mu$-pseudo almost automorphic solutions to abstract partial neutral functional differential equations with infinite delay 下载免费PDF全文
Yong-Kui Chang G. M. N''Gu ''{e}r ''{e}kat Rui Zhang 《Journal of Applied Analysis & Computation》2016,6(3):628-664
In this article, we introduce and investigate the concept of $\mu$-Stepanov-like pseudo almost automorphic functions of class $h$ and class infinity via measure theory. We present new results on completeness and composition theorems for the space of such functions. To illustrate our main results, we provide some applications to an abstract partial neutral functional differential equation with infinite delay. 相似文献
22.
In Bayesian analysis, the Markov Chain Monte Carlo (MCMC)
algorithm is an efficient and simple method to compute posteriors. However, the
chain may appear to converge while the posterior is improper, which will leads
to incorrect statistical inferences. In this paper, we focus on the necessary and
sufficient conditions for which improper hierarchical priors can yield proper
posteriors in a multivariate linear model. In addition, we carry out a simulation
study to illustrate the theoretical results, in which the Gibbs sampling and
Metropolis-Hasting sampling are employed to generate the posteriors. 相似文献
23.
24.
用飞行时间二次离子质谱(TOF-SIMS)分析研究了冬虫夏草中两个最重要的药效活性物质,甘露醇和虫草素,重点研究对应质量数251 amu的质谱峰含有的化学信息。利用TOF-SIMS高质量分辨率的优势, 检测并识别251和252 amu质谱峰的信号有可能不是保健药理活性物质虫草素C10H13N5O3(251 amu)产生的分子离子峰M+,[M+H]+,这或许就是文献中有关研究虫草素存在争论的原因。TOF-SIMS分析结果为进一步解读251 amu质谱峰的化学内含、深入研究冬虫夏草中虫草素提供了依据;同时就甘露醇对应的(181 amu附近)TOF-SIMS负离子质谱峰做了细致的解读, 确认181 amu质谱峰是识别冬虫夏草中甘露醇的可靠依据。本研究证明, TOF-SIMS是分析、研究、鉴别冬虫夏草的有效手段。 相似文献
25.
设计了一种狭缝柔性结构的光学元件调节机构,使光学元件在具备较高调节精度的同时,保持较高的导向精度。采用弹性力学应力函数法分析了狭缝柔性结构的刚度,以径向刚度与轴向刚度的比值为目标函数,对狭缝柔性结构尺寸参数进行了优化,在不超过柔性结构材料屈服应力等约束条件下,刚度比最优值达到1 573.6,较大的刚度比值可以减小调节机构的耦合位移,从而提高机构的导向精度。该结构加工装配方便,可实现三自由度(θx-θy-Z)调节。对优化后的柔性结构进行仿真分析,结果表明:径向刚度与轴向刚度比值的仿真值为1 660.4,解析值与仿真值误差为5.23%,证明了刚度分析方法的有效性。优化后的结构,轴向调节行程为2.09 mm,绕x轴偏转角度调节行程为±16.6 mrad,绕y轴偏转角度调节行程可达到±14.4 mrad,满足光学元件调节的大行程要求。 相似文献
26.
通过某些加权或非加权的Herz空间,将关于乘子算子有界性的H\"{o}rmander条件用一个更弱的条件来替代,并建立起乘子算子的一些有界性结果. 作为文中主要定理的直接推论,一些关于乘子算子有界性的著名结果得到了改进或者直接导出. 相似文献
27.
IntroductionThegreatprogressinabzymehasbeenmadeduringthelastdecade[1].Thekeytothepreparationofabzymeisthedesignofhapten.Onthe... 相似文献
28.
�� �������ソ�����������ε����ƽ��� 《核聚变与等离子体物理》2014,34(4):374-378
The electron densities in the atmospheric pressure helium plasma were calculated by means of electron drift velocity and the jet velocity respectively. The electron velocity and jet velocity can be calculated by means of helium plasma jet current measured by a dielectric probe and plasma discharge current signal measured by voltage probes. The results show that the estimated electron densities of the helium plasma jet calculated from electron drift velocity and the jet velocity are in the order of 10 11 cm -3 and they increase with applied voltage. There is a little fluctuation in the value of the electron density along the jet axis of the plasma. This result is the same as the measured electron density in atmospheric pressure helium non-thermal plasma jet by using a Rogowski coil and a Langmuir probe. This is in one order lower than the electron density measured by microwave antenna. 相似文献
29.
Models for weather and climate prediction are complex, and each
model typi-cally has at least a small number of phenomena that are
poorly represented, such as perhaps the Madden-Julian Oscillation
(MJO for short) or El Ni\~{n}o-Southern Oscillation (ENSO for short)
or sea ice. Furthermore, it is often a very challenging task to
modify and improve a complex model without creating new
deficiencies. On the other hand, it is sometimes possible to design
a low-dimensional model for a particular phenomenon, such as the MJO
or ENSO, with significant skill, although the model may not
represent the dynamics of the full weather-climate system. Here a
strategy is proposed to mitigate these model errors by taking
advantage of each model''s strengths. The strategy involves
inter-model data assimilation, during a forecast simulation, whereby
models can exchange information in order to obtain more faithful
representations of the full weather-climate system. As an initial
investigation, the method is examined here using a simplified
scenario of linear models, involving a system of stochastic partial
differential equations (SPDEs for short) as an imperfect tropical
climate model and stochastic differential equations (SDEs for short)
as a low-dimensional model for the MJO. It is shown that the MJO
prediction skill of the imperfect climate model can be enhanced to
equal the predictive skill of the low-dimensional model. Such an
approach could provide a route to improving global model forecasts
in a minimally invasive way, with modifications to the prediction
system but without modifying the complex global physical model
itself. 相似文献
30.