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Quantifying the Euphrates Electric Conductivity Depending on Parameters by Dimensional Analysis Method
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作者 Ali Hassan Hommadi Nadhir Al-Ansari 《Engineering(科研)》 CAS 2023年第5期301-317,共17页
The searching about methods to connect the variables with each other to reach equations including multi variables. The dimensional analysis is a method to facilitate the solution of difficult mathematic equations and ... The searching about methods to connect the variables with each other to reach equations including multi variables. The dimensional analysis is a method to facilitate the solution of difficult mathematic equations and experimental formulas;therefore methods of simplifying the difficult equations and obtaining a new equation with different variables is needed. In this study will use 2 methods (statically with dimensionally analysis) to obtain electric conductivity of water of Euphrates river by multi parameters that are time (t), temperature (Te), density, viscosity, discharge and water depth in upstream of Alhindya barrage which located in Babylon governorate, Iraq during winter 2019. The equations were obtained for EC with Te and t by data were collected from Alhindya barrage office with R<sup>2</sup> = 0.999 and R<sup>2</sup> = 0.995 by statically ways. Dimension analysis was utilized via 2 stages. In first stage was obtained on equation of EC with respect to Te, water density (ρ) and dynamic viscosity (μ) with constant time, depth of water and discharge and we obtain on R<sup>2</sup> was 0.994 and R<sup>2</sup> = 0.986. In second stage was obtained formula of EC with respect to Te, water density (ρ), dynamic viscosity (μ), with variable time, depth of water and discharge with we obtain on R<sup>2</sup> = 0.945 and R<sup>2</sup> = 0.94. The result of research indicates that applying the dimension analysis to connect more than one variable with each other to find best solutions and best methods to facilitate the solving the equations. From dimension analysis gave a clear visualization of the association of several variables to give a result that helps measure the electrical conductivity of water in the absence of a water test device. 展开更多
关键词 Electric Conductivity TEMPERATURE Dimension analysis Statistical analysis
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Three Dimensional Kinematics Analysis of the Independent Suspension Multibody System 被引量:2
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作者 陈欣 林逸 +1 位作者 孙大刚 白文辉 《Journal of Beijing Institute of Technology》 EI CAS 1997年第4期80-86,共7页
Based on the theory of multibody system dynamics, the spatial kinematics analysis of the Mcpherson independent suspension widely used in the car was carried out. A practical and simpler method was provided to reduce t... Based on the theory of multibody system dynamics, the spatial kinematics analysis of the Mcpherson independent suspension widely used in the car was carried out. A practical and simpler method was provided to reduce the number of the generalized coordinates and constraint functions. By solving the nonlinear equations, the motion of any points in the whole suspension and wheel system can be predicted, including the spatial changes of the wheel alignment parameters which are of great importance to the car performances. 展开更多
关键词 independent suspension three dimension kinematic analysis multibody system
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Algorithms for Empirical Equations in Terms of the Cosmic Microwave Background Temperature
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作者 Tomofumi Miyashita 《Journal of Modern Physics》 2024年第10期1567-1585,共19页
Previously, we presented several empirical equations using the cosmic microwave background (CMB) temperature. Next, we propose an empirical equation for the fine-structure constant. Considering the compatibility among... Previously, we presented several empirical equations using the cosmic microwave background (CMB) temperature. Next, we propose an empirical equation for the fine-structure constant. Considering the compatibility among these empirical equations, the CMB temperature (Tc) and gravitational constant (G) were calculated to be 2.726312 K and 6.673778 × 10−11 m3∙kg−1∙s−2, respectively. Every equation can be explained numerically in terms of the Compton length of an electron (λe), the Compton length of a proton (λp) and α. Furthermore, every equation can also be explained in terms of the Avogadro number and the number of electrons at 1 C. We show that every equation can be described in terms of the Planck constant. Then, the ratio of the gravitational force to the electric force can be uniquely determined with the assumption of minimum mass. In this report, we describe the algorithms used to explain these equations in detail. Thus, there are no dimension mismatch problems. 展开更多
关键词 Temperature of the Cosmic Microwave Background Minimum Mass The Ratio of Gravitational Force to Electric Force Dimension analysis Redefinition Method Fine Structure Constant
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Analysis of normal human retinal vascular network architecture using multifractal geometry 被引量:1
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作者 Stefan Talu Sebastian Stach +2 位作者 Dan Mihai Calugaru Carmen Alina Lupascu Simona Delia Nicoara 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第3期434-438,共5页
AIM:To apply the multifractal analysis method as a quantitative approach to a comprehensive description of the microvascular network architecture of the normal human retina.METHODS:Fifty volunteers were enrolled in ... AIM:To apply the multifractal analysis method as a quantitative approach to a comprehensive description of the microvascular network architecture of the normal human retina.METHODS:Fifty volunteers were enrolled in this study in the Ophthalmological Clinic of Cluj-Napoca,Romania,between January 2012 and January 2014. A set of 100 segmented and skeletonised human retinal images,corresponding to normal states of the retina were studied. An automatic unsupervised method for retinal vessel segmentation was applied before multifractal analysis. The multifractal analysis of digital retinal images was made with computer algorithms,applying the standard boxcounting method. Statistical analyses were performed using the Graph Pad In Stat software.RESULTS:The architecture of normal human retinal microvascular network was able to be described using the multifractal geometry. The average of generalized dimensions(D_q)for q=0,1,2,the width of the multifractal spectrum(Δα=α_(max)-α_(min))and the spectrum arms' heights difference(│Δf│)of the normal images were expressed as mean±standard deviation(SD):for segmented versions,D_0=1.7014±0.0057; D_1=1.6507±0.0058; D_2=1.5772±0.0059; Δα=0.92441±0.0085; │Δf│= 0.1453±0.0051; for skeletonised versions,D_0=1.6303±0.0051; D_1=1.6012±0.0059; D_2=1.5531± 0.0058; Δα=0.65032±0.0162; │Δf│= 0.0238±0.0161. The average of generalized dimensions(D_q)for q=0,1,2,the width of the multifractal spectrum(Δα)and the spectrum arms' heights difference(│Δf│)of the segmented versions was slightly greater than the skeletonised versions.CONCLUSION:The multifractal analysis of fundus photographs may be used as a quantitative parameter for the evaluation of the complex three-dimensional structure of the retinal microvasculature as a potential marker for early detection of topological changes associated with retinal diseases. 展开更多
关键词 generalized dimensions multifractal retinal vessel segmentation retinal image analysis retinal microvasculature standard box-counting method
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Automated Dynamic Cellular Analysis in Time-Lapse Microscopy
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作者 Shuntaro Aotake Chamidu Atupelage +3 位作者 Zicong Zhang Kota Aoki Hiroshi Nagahashi Daisuke Kiga 《Journal of Biosciences and Medicines》 2016年第3期44-50,共7页
Analysis of cellular behavior is significant for studying cell cycle and detecting anti-cancer drugs. It is a very difficult task for image processing to isolate individual cells in confocal microscopic images of non-... Analysis of cellular behavior is significant for studying cell cycle and detecting anti-cancer drugs. It is a very difficult task for image processing to isolate individual cells in confocal microscopic images of non-stained live cell cultures. Because these images do not have adequate textural variations. Manual cell segmentation requires massive labor and is a time consuming process. This paper describes an automated cell segmentation method for localizing the cells of Chinese hamster ovary cell culture. Several kinds of high-dimensional feature descriptors, K-means clustering method and Chan-Vese model-based level set are used to extract the cellular regions. The region extracted are used to classify phases in cell cycle. The segmentation results were experimentally assessed. As a result, the proposed method proved to be significant for cell isolation. In the evaluation experiments, we constructed a database of Chinese Hamster Ovary Cell’s microscopic images which includes various photographing environments under the guidance of a biologist. 展开更多
关键词 High Dimension Feature analysis Microscopic Cell Image Cell Division Cycle Identification Active Contour Model K-Means Clustering
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Novel modeling on numerical computing the geo-deformation information in coalmine based on the GIS-Excel 被引量:1
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作者 杨可明 Wang Libo +3 位作者 Zhang Tao Qian Xiaoli Wang Linwei Liu Shiwen 《High Technology Letters》 EI CAS 2013年第2期156-161,共6页
Numerical simulation modeling is a hotspot in the geological engineering computing field. Tak- ing a fast Langrangian analysis of continua in 3 dimensions (FLAC3D) numerical modeling on com- puting the geo-deformati... Numerical simulation modeling is a hotspot in the geological engineering computing field. Tak- ing a fast Langrangian analysis of continua in 3 dimensions (FLAC3D) numerical modeling on com- puting the geo-deformation information caused by the mining subsidence in a coalmine for example, a new GIS-Excel modeling method is proposed to build geologic strata within the simulation range combined with the coal-seam dip angle of the underground mining working-planes. First of all, the coal-seam model of the numerical computing is built by using the geographic information system (GIS) according to the stripe-through principle and the calculating formula on the size of the model blocks in the paper defined, then the FLAC3D numerical computing model of all geologic strata with- in the simulation range is also built based on the calculating formula of thickness of each stratum and the Excel fast computing advantages. The GIS-Excel method is good at the higher modeling accuracy, seldom making mistakes and consuming less time. The reliability and validity of the method is veri- fied well by its practical applications in the coalmine area. 展开更多
关键词 numerical simulation mining subsidence fast Langrangian analysis of continua in 3dimensions FLAC3D) modeling geo-deformation information geographic information system (GIS)
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Theoretical study on constitutive relationship of fiber reinforced polymer confined concrete
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作者 张力文 《Journal of Chongqing University》 CAS 2009年第1期37-49,共13页
We proposed a bilinearity constitutive curve model of fiber reinforced polymer(FRP) confined concrete which includes a parabola in the first stage and a straight line in the second stage. The FRP-confined concrete has... We proposed a bilinearity constitutive curve model of fiber reinforced polymer(FRP) confined concrete which includes a parabola in the first stage and a straight line in the second stage. The FRP-confined concrete has powerful confinement status and weak confinement status leading to different equations of parabola. We analyzed the impacts of factors such as confinement ratio and restrain stiffness on confined concrete compressive strength,ultimate strain and other control parameters through finite element analysis. The results show that the confinement ratio determines the confinement status,and the increase of the confinement ratio has a limited capacity to increase the compressive strength. The deformation of confined concrete is influenced by restrain stiffness. The stronger the restrain stiffness is,the less the lateral deformation is and the greater ultimate axial strain will be. The consideration of equivalent section coefficient kse is needed in the non-circular section confined concrete. We analyzed the results and proposed boundary values of strong and weak confinement styles,a peak/inflection point stress and strain model,and a compressive strength and ultimate strain model. 展开更多
关键词 numerical simulation fiber reinforced polymer confmed concrete stress-strain curve dimension analysis
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Investigation of Rotor Radial Rotating Error upon AMB System
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作者 WANG Kai LI Yan 《International Journal of Plant Engineering and Management》 2006年第2期106-110,共5页
This paper first suggests the use of the Fourier frequency transmission method of two dimensions function ( 2D FFT) to analyze radial rotating errors that occurred in a rotor. Based on this method a magnetic rotor i... This paper first suggests the use of the Fourier frequency transmission method of two dimensions function ( 2D FFT) to analyze radial rotating errors that occurred in a rotor. Based on this method a magnetic rotor is measured. The authors point out that the main cause to affect radial rotating accuracy of the rotating shaft at a high speed is the dynamic imbalance of the shaft itself. Finally the feedforward control scheme is suggested to improve the accuracy of the shaft in an active magnetic bearing ( AMB ) system. 展开更多
关键词 AMB( active magnetic bearing) rotating errors 2D FFT( Fourier frequency analysis method of two dimensions function) FEED-FORWARD
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