Aggregation of particles which move on deterministic trajectories with fractal dimension two. I. A simple and new model for DLA

Relative permeability and transverse relaxation time are both important physical parameters of rock physics. In this paper, a new transformation model between the transverse relaxation time and the wetting phase’s relative permeability is established. The data shows that the cores in the northwest of China have continuous fractal dimension characteristics, and great differences existed in the different pore size scales. Therefore, a piece-wise method is used to calculate the fractal dimension in our transformation model. The transformation results are found to be quite consistent with the relative permeability curve of the laboratory measurements. Based on this new model, we put forward a new method to identify reservoir in tight sandstone reservoir. We focus on the Well M in the northwestern China. Nuclear magnetic resonance (NMR) logging is used to obtain the point-by-point relative permeability curve. In addition, we identify the gas and water layers based on new T2-Kr model and the results showed our new method is feasible. In the case of the price of crude oil being low, this method can save time and reduce the cost.

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Establishment and application of a structure evolution model for aqueous foam based on fractal theory

RSC Advances ◽

10.1039/c6ra24790c ◽

2017 ◽

Vol 7 (7) ◽

pp. 3650-3659 ◽

Cited By ~ 7

Author(s):

Fei Wang ◽

Zhaomin Li ◽

Hailong Chen ◽

Xibin Zhang

Keyword(s):

Fractal Dimension ◽

Fractal Theory ◽

Evolution Model ◽

Structure Evolution ◽

Exponential Equation ◽

New Model ◽

Model Based ◽

Aqueous Foam ◽

Non Linear ◽

Evolution Trend

A new model based on fractal theory is proposed for the simulation of aqueous foam. It reveals that the evolution trend of the fractal dimension of foam is non-linear with the changing of time following an exponential equation.

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Research on a Fractal Dimension Calculation Method for a Nano-Polymer Microspheres Dispersed System

Frontiers in Chemistry ◽

10.3389/fchem.2021.732797 ◽

2021 ◽

Vol 9 ◽

Author(s):

Wenyue Zhao ◽

Jinming Yan ◽

Ganggang Hou ◽

Pengxiang Diwu ◽

Tongjing Liu ◽

...

Keyword(s):

Particle Size ◽

Fractal Dimension ◽

Calculation Method ◽

Average Particle Size ◽

Average Particle ◽

New Model ◽

Box Counting ◽

Dispersed System ◽

Calculation Results ◽

Counting Model

Polymer microspheres (PMs) are a kind of self-similar volume expansion particle, and their fractal dimension varies with hydration swelling. However, there is no unique fractal dimension calculation method for their characteristics. A new model is established in this paper, which is particular to calculate the fractal dimension of PMs. We carried out swelling hydration experiments and scanning electron microscope (SEM) experiments to verify the new model. The new model and the box-counting model were used to calculate the fractal dimensions of PMs based on the hydration experiment results. Then, a comparison of the calculation results of the two methods was used to verify the validity of the model. Finally, according to the new model calculation results, the fractal dimension characteristics of PMs were analyzed. The research results indicate that the new model successfully correlates the cumulative probability of the PMs dispersed system with the fractal dimension and makes fractal dimension calculation of PMs more accurate and convenient. Based on the experiment results, the new model was used to calculate the fractal dimension of PMs and the box-counting model, and its findings were all 2.638 at initial state hydration and 2.739 and 2.741 at hydration time as of day 1. This result verifies the correctness of the new model. According to the hydration swelling experiments and the new model calculation results, the fractal dimension is linear correlated to the average particle size of PMs and the standard deviation average particle size. This means the fractal dimension of PMs represents the space occupancy ability and space occupancy effectiveness.

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The Hitachi Model HS-8 Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061203 ◽

1967 ◽

Vol 25 ◽

pp. 238-239

Author(s):

H. Akabori ◽

K. Nishiwaki ◽

K. Yoneta

Keyword(s):

Electron Microscope ◽

New Model ◽

Predecessor Model

By improving the predecessor Model HS- 7 electron microscope for the purpose of easier operation, we have recently completed new Model HS-8 electron microscope featuring higher performance and ease of operation.

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Use of fractals to describe microstructures of porous thick-film platinum electrodes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100121971 ◽

1992 ◽

Vol 50 (1) ◽

pp. 314-315

Author(s):

Steven D. Toteda

Keyword(s):

Fractal Dimension ◽

Power Plants ◽

Electrical Response ◽

Cubic Phase ◽

Platinum Electrodes ◽

Fine Grained ◽

Impedance Response ◽

Platinum Particles ◽

Energy Surfaces ◽

Highly Porous

Zirconia oxygen sensors, in such applications as power plants and automobiles, generally utilize platinum electrodes for the catalytic reaction of dissociating O2 at the surface. The microstructure of the platinum electrode defines the resulting electrical response. The electrode must be porous enough to allow the oxygen to reach the zirconia surface while still remaining electrically continuous. At low sintering temperatures, the platinum is highly porous and fine grained. The platinum particles sinter together as the firing temperatures are increased. As the sintering temperatures are raised even further, the surface of the platinum begins to facet with lower energy surfaces. These microstructural changes can be seen in Figures 1 and 2, but the goal of the work is to characterize the microstructure by its fractal dimension and then relate the fractal dimension to the electrical response. The sensors were fabricated from zirconia powder stabilized in the cubic phase with 8 mol% percent yttria. Each substrate was sintered for 14 hours at 1200°C. The resulting zirconia pellets, 13mm in diameter and 2mm in thickness, were roughly 97 to 98 percent of theoretical density. The Engelhard #6082 platinum paste was applied to the zirconia disks after they were mechanically polished ( diamond). The electrodes were then sintered at temperatures ranging from 600°C to 1000°C. Each sensor was tested to determine the impedance response from 1Hz to 5,000Hz. These frequencies correspond to the electrode at the test temperature of 600°C.

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516: A Simplified Method to Estimate the Absolute Renal Uptake of 99MTC-DMSA: Evaluation with a New Model using the Radioactivity of Nephrectomy Specimens as Reference

The Journal of Urology ◽

10.1016/s0022-5347(18)34756-6 ◽

2005 ◽

Vol 173 (4S) ◽

pp. 140-141

Author(s):

Mariana Lima ◽

Celso D. Ramos ◽

Sérgio Q. Brunetto ◽

Marcelo Lopes de Lima ◽

Carla R.M. Sansana ◽

...

Keyword(s):

New Model ◽

Renal Uptake ◽

Simplified Method ◽

The Absolute

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476 Chronic left atrial volume and pressure overload in the goat: a new model of sustained atrial fibrillation

EP Europace ◽

10.1016/s1099-5129(05)80314-9 ◽

2005 ◽

Vol 7 ◽

pp. 107-107

Keyword(s):

Atrial Fibrillation ◽

Left Atrial ◽

Pressure Overload ◽

Left Atrial Volume ◽

Atrial Volume ◽

New Model

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Analyzing Stochastic Dependence of Cognitive Processes in Multidimensional Source Recognition

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169/a000261 ◽

2014 ◽

Vol 61 (5) ◽

pp. 402-415 ◽

Cited By ~ 9

Author(s):

Thorsten Meiser

Keyword(s):

Cognitive Processes ◽

Model Complexity ◽

Multinomial Model ◽

Stochastic Dependence ◽

New Model ◽

Multinomial Processing Tree ◽

Cognitive States ◽

The Family ◽

Tree Models ◽

Flexible Framework

Stochastic dependence among cognitive processes can be modeled in different ways, and the family of multinomial processing tree models provides a flexible framework for analyzing stochastic dependence among discrete cognitive states. This article presents a multinomial model of multidimensional source recognition that specifies stochastic dependence by a parameter for the joint retrieval of multiple source attributes together with parameters for stochastically independent retrieval. The new model is equivalent to a previous multinomial model of multidimensional source memory for a subset of the parameter space. An empirical application illustrates the advantages of the new multinomial model of joint source recognition. The new model allows for a direct comparison of joint source retrieval across conditions, it avoids statistical problems due to inflated confidence intervals and does not imply a conceptual imbalance between source dimensions. Model selection criteria that take model complexity into account corroborate the new model of joint source recognition.

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