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1.
In this study, several simple aspects associated with the periodic table (PT) of the elements are commented. First, the connection of the PT with the structure of a seven-dimensional Boolean hypercube leads afterward to discuss the nature of those PT elements bearing prime atomic numbers. Second, the use of quantum similarity (QS) to obtain an alternative insight on the PT element relations will be also developed. The foundation of the second part starts admitting that any element of the PT can be attached to a schematic electronic density function, constructed with a single Gaussian function: a Gaussian atomic density function, allowing to consider the PT elements as a set of quantum objects, and permits a straightforward construction of a QS matrix. Such QS scheme can be applied to the whole PT or to any subset of it. Manipulation of the QS matrices attached to any quantum object set allows the evaluation of statistical-like values, acting as coordinates to numerically or graphically represent the chosen PT atomic element sets. © 2019 Wiley Periodicals, Inc.  相似文献   
2.
In recent years, the fingerprint of high‐performance liquid chromatography has been extensively applied in the identification and quality control of traditional Chinese medicine. It can be a potential protocol for assessing the authenticity, stability and consistency of traditional Chinese medicine and guaranteeing the expected biological activity. In this paper, a method using high‐performance liquid chromatography to identify and control the quality of the extract of Taraxacum mongolicum Hand.‐Mazz. (TME) was established. With this method, the correlation coefficients of the similarity of 10 batches were ≥0.994. The TME displayed a steady proliferative effect in Lactobacillus plantarum. In brief, this study successfully built a reliable, simple and efficient method to control and confirm the quality and the stability of biological activity of the TME.  相似文献   
3.
Lie group classification for a diffusion‐type system that has applications in plasma physics is derived. The classification depends on the values of 5 parameters that appear in the system. Similarity reductions are presented. Certain initial value problems are reduced to problems with the governing equations being ordinary differential equations. Examples of potential symmetries are also presented.  相似文献   
4.
何翔 《应用光学》2023,44(2):314-322
针对半片光伏组件电致发光(electroluminescence,EL)缺陷自动识别过程中训练用样本不足导致模型过拟合的问题,采用深度卷积生成对抗网络(deep convolutional generative adversarial networks,DCGANs)生成可控制属性的半片光伏组件EL图像,再采用多尺度结构相似性(multiscale structural similarity,MS-SSIM)指标对生成的EL图像与拍摄的EL图像之间的相似程度进行了评估。评估结果得到,使用DCGANs生成的所有类型半片光伏组件的EL图像与拍摄的EL图像的MS-SSIM指标都大于0.55,大部分的MS-SSIM值在0.7附近。在分类模型的训练过程中,测试集准确率随着训练集中生成图像数量的增加而升高,当生成图像数量达到6 000张时,测试集准确率达到97.92%。实验结果表明,采用DCGANs能够生成高质量且可控制属性的半片光伏组件EL图像,较好地解决因缺少训练样本而导致的模型过拟合问题。  相似文献   
5.
大气边界层模拟的湍流相似   总被引:3,自引:0,他引:3  
大气边界层的风洞模拟,是目前研究建筑物风载,污染质的大气扩散,以及解决某些环境科学和军事科学中大型课题的重要手段之一。在许多国家,风洞模拟已成为环境部门设计大型工程、林区、厂区和城区规划的主要依据。最初的大气边界层模拟装置,仅考虑形成一定的平均风速廓线,并未考虑到气流的湍流特性。微气象学的研究表明,大气的湍流特性是影响扩散的主要因素。特别是Monin和Obukhov通过大量实测资料提出大气表面层中的相似性理论,成为研究大气扩散的重要依据。从50年代开始,一些研究大气扩散和建筑物风载问题的长实验段风洞相继筹划和建立。其中较著名的有,美国科罗拉多州立大学的1.8米×1.8米×30米的回流式长实验段气  相似文献   
6.
Theκ-εturbulence model,considering the effect of buoyancy on turbulentkinetic energy and its dissipation rate,is adopted to present a mathematical model forround plumes and jets.There are similarity solutions in the uniform environment.Taking into account the conservation of momentum and heat flux.Finite AnalyticMethod is applied to obtain the similarity functions of velocity,temperature andturbulent kinetic energy.The agreement between the calculated and experimental datais good.  相似文献   
7.
An approximate analytical solution is provided for one-dimensional, counter- current, spontaneous imbibition of a wetting phase (water) into a semi-infinite porous medium. The solution is based on the assumption that a similarity solution exists for the displacement process. This assumption, in turn, rests on the assumption that the set of relative permeability and capillary pressures curves are unique functions of saturation and do not depend on the nature of the displacement. It further rests on the assumption that the saturation at the imbibition face does not vary with time. It is demonstrated that the solution is in agreement with results obtained from experiments and also numerical analyses of these experiments. The experiments utilize cylindrical samples with the radial surface and one end-face sealed, and with counter-current imbibition occurring at the open end-face. The stage of the experiment that is modeled by the present solution is the period before the imbibition front contacts the sealed end-face. An important finding of the present analysis is that the pressure upstream of the advancing invasion front is a constant. A second, improved solution is also presented; this solution is an iterative, series solution of an integral-differential equation. It converges to a stable solution in very few terms.  相似文献   
8.
断裂力学中的相似方法   总被引:3,自引:0,他引:3  
赵亚溥 《力学进展》1998,28(3):323-338
不论是材料的断裂强度还是结构的承载能力均存在着明显的“尺度效应”.本文旨在较全面且系统地总结断裂力学中的相似方法、无量纲数及其断裂力学中有关的尺度率,并给出作者自己对某些问题的看法和认识  相似文献   
9.
A laboratory study including physical modeling of filtration processes in porous beds with similarity criteria satisfied is performed. It is demonstrated that weak dynamic actions on stressed host rock blocks can initiate repacking of the system of blocks, leading to an increase in pressure in the productive bed and in oil recovery. __________ Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 1, pp. 131–138, January–February, 2006.  相似文献   
10.
Redistribution of a LNAPL lens (oil) at the phreatic surface is described using a multi-phase flow model, with emphasis on the effect of oil entrapment by water. The flow process is analyzed under the assumption that the vertical capillary and gravitational forces balance. Vertical integration leads to explicit functions which approximate the relations between the free oil volume per unit lateral area and the vertically averaged oil relative permeability on the one hand and the vertical position of the interface between zones with either two or three phases on the other hand. A linear relation between the trapped and free oil volume per unit lateral area approximates the vertically integrated nonlinear expression for the trapped oil saturation. The resulting differential equation admits a similarity solution describing the lateral spreading of free oil and the amount and location of trapped oil. Comparison with illustrative numerical computations, which are based on the nonreduced flow model in a two-dimensional planar or axisymmetric domain, shows that the analytical solution provides a good approximation of the free oil distribution at all later times.  相似文献   
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