A simplified and modified model for long rod penetration based on ovoids of Rankine

Abstract:A simple nonlinear beat-to-beat model of the human cardiovascular system has been studied. The model, introduced by DeBoer et al. was a simplified linearized version. We present a modified model which allows to investigate the nonlinear dynamics of the cardiovascular system. We found that an increase in the -sympathetic gain, via a Hopf bifurcation, leads to sustained oscillations both in heart rate and blood pressure variables at about 0.1 Hz (Mayer waves). Similar oscillations were observed when increasing the -sympathetic gain or decreasing the vagal gain. Further changes of the gains, even beyond reasonable physiological values, did not reveal another bifurcation. The dynamics observed were thus either fixed point or limit cycle. Introducing respiration into the model showed entrainment between the respiration frequency and the Mayer waves.

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Control Design for Current Loop of PMSM Using A Modified Model-Compensation ADRC Controller

2020 39th Chinese Control Conference (CCC) ◽

10.23919/ccc50068.2020.9189452 ◽

2020 ◽

Author(s):

Yingning Gao ◽

Hui Zhao ◽

Kemao Ma ◽

Xin Huo

Keyword(s):

Control Design ◽

Current Loop ◽

Modified Model

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Controlled Growth of the Non-centrosymmetric Zn(3-ptz)2 and Zn(Oh)(3-ptz) Metal-organic Frameworks

10.26434/chemrxiv.7588640.v1 ◽

2019 ◽

Author(s):

javier enriquez ◽

Ignacio Chi-Duran ◽

Carolina Manquian ◽

Felipe Herrera ◽

Ruben Fritz ◽

...

Keyword(s):

Single Crystal ◽

Nonlinear Optical ◽

Metal Organic Frameworks ◽

Molar Ratio ◽

Thermal Synthesis ◽

Small Crystals ◽

Alkaline Environments ◽

Potential Applications ◽

Metal Organic ◽

Long Rod

Non-centrosymmetric single-crystal metal-organic frameworks (MOF) are promising candidates for phase-matched nonlinear optical communication, but typical hydrothermal synthesis produces small crystals with relatively low transmittance and poor phase matching. We study the effect of the metal-to-ligand molar ratio and reaction pH on the hydro-thermal synthesis of the non-centrosymmetric Zn(3-ptz)2 and Zn(OH)(3-ptz) MOFs with in-situ ligand formation. In acidic environments, we find that decreasing the amount of ligand below the stoichiometric molar ratio 1:2 also produces highly transparent single-crystal octahedrons of Zn(3-ptz)2. In alkaline environments, we obtain long rod-like Zn(OH)(3-ptz) crystals whose length exceeds previous reports by up to four orders of magnitude. Potential applications of these results in the development of MOF-based nonlinear optical devices are discussed.

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Internet usage patterns and gender differences: a decision tree approach

10.31124/advance.8040185 ◽

2019 ◽

Author(s):

Dijana Kovacevic ◽

Ljiljana Kascelan

Keyword(s):

Decision Tree ◽

Internet Usage ◽

The Internet ◽

Modified Model ◽

Explanatory Variables ◽

Internet Users ◽

Usage Patterns ◽

And Gender ◽

The One ◽

Web Developers

the present study deals with a more detailed, and updated, modified model that allows for the identification of internet usage patterns by gender. The model was modified due to the development of the internet and new access models, on the one hand, and to the fact that previous studies mainly focuses on various individual (non-interactive) influences of certain factors, on the other. The Decision Tree (DT) method, which is used in our study, does not require a pre-defined underlying relationship. In addition, the method allows a great many explanatory variables to be processed and the most important variables are easy to identify. Obtained results can serve as to web developers and designers, since by indicating the differences between male and female internet users in terms of their behaviour on the internet it can help in deciding when, where and how to address and appeal to which section of the user base. It is especially important to know their online preferences in order to enable the adequate and targeted placement of information, actions or products and services for the intended target groups.

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A two-dimensional air discharge modified model under unipolar square pulse voltage at low temperature and sub-atmospheric pressure

IEEE Access ◽

10.1109/access.2021.3070335 ◽

2021 ◽

pp. 1-1

Author(s):

Zhihang Zhao ◽

Xinlao Wei ◽

Shuang Song ◽

Lin Cui ◽

Zhonghua Zhang ◽

...

Keyword(s):

Low Temperature ◽

Atmospheric Pressure ◽

Pulse Voltage ◽

Two Dimensional ◽

Modified Model ◽

Air Discharge

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Modification and Validation of the Phosphate Removal Model: A Multicenter Study

Kidney & Blood Pressure Research ◽

10.1159/000511375 ◽

2021 ◽

pp. 1-10

Author(s):

Weichen Zhang ◽

Qiuna Du ◽

Jing Xiao ◽

Zhaori Bi ◽

Chen Yu ◽

...

Keyword(s):

Polynomial Regression ◽

External Validation ◽

Original Model ◽

Phosphate Concentration ◽

Phosphate Removal ◽

Internal Validation ◽

Modified Model ◽

New Model ◽

Significant Difference ◽

Removal Model

Background: Our research group has previously reported a noninvasive model that estimates phosphate removal within a 4-h hemodialysis (HD) treatment. The aim of this study was to modify the original model and validate the accuracy of the new model of phosphate removal for HD and hemodiafiltration (HDF) treatment. Methods: A total of 109 HD patients from 3 HD centers were enrolled. The actual phosphate removal amount was calculated using the area under the dialysate phosphate concentration time curve. Model modification was executed using second-order multivariable polynomial regression analysis to obtain a new parameter for dialyzer phosphate clearance. Bias, precision, and accuracy were measured in the internal and external validation to determine the performance of the modified model. Results: Mean age of the enrolled patients was 63 ± 12 years, and 67 (61.5%) were male. Phosphate removal was 19.06 ± 8.12 mmol and 17.38 ± 6.75 mmol in 4-h HD and HDF treatments, respectively, with no significant difference. The modified phosphate removal model was expressed as Tpo4 = 80.3 × C45 − 0.024 × age + 0.07 × weight + β × clearance − 8.14 (β = 6.231 × 10−3 × clearance − 1.886 × 10−5 × clearance2 – 0.467), where C45 was the phosphate concentration in the spent dialysate measured at the 45th minute of HD and clearance was the phosphate clearance of the dialyzer. Internal validation indicated that the new model was superior to the original model with a significantly smaller bias and higher accuracy. External validation showed that R2, bias, and accuracy were not significantly different than those of internal validation. Conclusions: A new model was generated to quantify phosphate removal by 4-h HD and HDF with a dialyzer surface area of 1.3–1.8 m2. This modified model would contribute to the evaluation of phosphate balance and individualized therapy of hyperphosphatemia.

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