Fractional-Order Discrete-Time SIR Epidemic Model with Vaccination: Chaos and Complexity

This research presents a new fractional-order discrete-time susceptible-infected-recovered (SIR) epidemic model with vaccination. The dynamical behavior of the suggested model is examined analytically and numerically. Through using phase attractors, bifurcation diagrams, maximum Lyapunov exponent and the 0−1 test, it is verified that the newly introduced fractional discrete SIR epidemic model vaccination with both commensurate and incommensurate fractional orders has chaotic behavior. The discrete fractional model gives more complex dynamics for incommensurate fractional orders compared to commensurate fractional orders. The reasonable range of commensurate fractional orders is between γ = 0.8712 and γ = 1, while the reasonable range of incommensurate fractional orders is between γ2 = 0.77 and γ2 = 1. Furthermore, the complexity analysis is performed using approximate entropy (ApEn) and C0 complexity to confirm the existence of chaos. Finally, simulations were carried out on MATLAB to verify the efficacy of the given findings.

Parameter Adjustment to Prevent the Overestimation of Peak Discharge in a Small Watershed

We revisit empirical methods to prevent the overestimation of peak discharge in a small watershed, in particular investigating the time-area method, which has not been considered in the overestimation problem of peak discharge. To avoid misapplying the same inlet time between the unit hydrograph and rational formula, distinct parameter adjustments for each method are proposed. We adopt the secondary basin response time for the unit hydrograph, rainfall duration for the rational formula, and time of concentration for the time-area method, as suitable parameters to adjust the estimation of peak discharge. In conclusion, adding 10 minutes to secondary basin response time, 20 minutes to rainfall duration, and 30 minutes to time of concentration, respectively, yields estimates within a reasonable range of specific discharge in a small watershed.

Towards Carbon Neutrality: The Impact of Renewable Energy Development on Carbon Emission Efficiency

The energy transition and carbon emission efficiency are important thrust and target functions, respectively, for achieving carbon neutrality in the future. Using a sample of 30 Chinese provinces from 2006 to 2018, we measured their carbon efficiency using the game cross-efficiency data envelopment analysis (DEA). Then, a random forest regression model was used to explore the impact of renewable energy development on regional carbon emission efficiency. The results are as follows. First, China’s carbon emission efficiency in the southeast coastal area was better than that in the northwest area. Second, renewable energy development first inhibited and then promoted carbon emission efficiency, and there existed a reasonable range. Third, through a regional heterogeneity analysis, the trend of the influence of renewable energy development on carbon emission efficiency was found to not be significantly different in eastern, central, and western China, but there was a certain gap in the reasonable range. Our study not only helps to promote the study of renewable energy development and the carbon neutral target, but also provides an important reference for Chinese policy-makers to design a reasonable carbon emissions reduction path.

A simple cornea deformation model

In this paper, we present a cornea deformation model based on the idea of extending the ‘neutral axis’ model to two-dimensional deformations. Considering this simple model, assuming the corneal tissue to behave like a continuous, isotropic and non-compressible material, we are able to partially describe, e.g., the observed deviation in refractive power after lenticule extraction treatments. The model provides many input parameters of the patient and the treatment itself, leading to an individual compensation ansatz for different setups. The model is analyzed for a reasonable range of various parameters. A semi-quantitative comparison to real patient data is performed.

Study on Plant Growth and Nutrient Uptake under Different Aeration Intensity in Hydroponics with the Application of Particle Image Velocimetry

Aeration is considered beneficial for hydroponics. However, little information is available on the effects of aeration, and even less on solutions that use bubble flow and their agronomic effects. In this study, the effects of aeration intensity on plants were studied through cultivation experiments and flow field visualization. It was found that the growth of plants did not increase linearly with an increase in aeration intensity. From the results of this study, when the aeration intensity was within the low range (0.07–0.15 L·L−1 NS·min−1), increasing the aeration intensity increased the plant growth. However, after the aeration intensity reached a certain extent (0.15–1.18 L·L−1 NS·min−1), some indicators did not change significantly. When the aeration intensity continued to increase (1.18–2.35 L·L−1 NS·min−1), growth began to decrease. These results show that for increasing dissolved oxygen and promoting plant growth, the rule is not “the higher the aeration intensity, the better”. There is a reasonable range of aeration intensity within which crops grow normally and rapidly. In addition, increasing the aeration intensity means increasing energy utilization and operating costs. In actual hydroponics production, it is very important to find a reasonable aeration intensity range.

Numerical Analysis of Friction Effects on Temperature and Phases within Forged Ti-6Al-4V Alloy Aeroengine Drum

Friction conditions significantly impact the temperature and phases of titanium forged parts, further directly affecting the microstructures and mechanical properties of final parts. In this paper, a 2D simplified finite element (FE) model combined with phase transition equations is developed to simulate a Ti-6Al-4V drum forging procedure. Then, friction effects on the temperature and phases of the forged drum are numerically analyzed and verified by experiments. The simulated results indicate that a reasonable range of friction factor is needed to obtain a relatively homogenous temperature distribution within the forged drum. Moreover, unlike its small influence on the α + β phase, improving friction obviously decreases the general levels of temperature and β phase and increases the homogeneities of α and β phases within the forged drum, which are associated with cooling rates and the heating effects of friction and deformation.

Orbital Design and Control for Jupiter-Observation Spacecraft

This paper investigates the evolution of orbits around Jupiter and designs a sun-synchronous repeating ground track orbit. In the dynamical models, the leading terms of the Jupiter’s oblateness are J2 and J4 terms. A reasonable range of ground track repetition parameter Q is given and the best observation orbit elements are selected. Meanwhile, the disturbing function acting on the navigation spacecraft is the atmospheric drag and the third body. The law of altitude decay of the spacecraft’s semimajor orbit axis caused by the atmospheric drag is studied, and the inclination perturbation caused by the sun’s gravity is analyzed. This paper designs a semimajor axis compensation strategy to maintain the orbit’s repeatability and proposes an initial inclination prebiased strategy to limit the local time at the descending node in a permitted range. In particular, these two methods are combined in the context of sun-synchronous repeating ground track orbit for better observation of the surface of Jupiter.

Ultrafiltration in Patients on Automated Peritoneal Dialysis with Homechoice Claria connected to Sharesource: A Pilot Study

Introduction: Fluid overload is an unavoidable problem in patients on peritoneal dialysis (PD) and is associated with poor outcomes. The aim of our study was to estimate ultrafiltration (UF) under different dextrose concentrations and clarify possible predictors of UF.Materials and methods: Seventy patients, with 1848 daily treatment records and 8266 single dwells on automated PD through Homechoice Claria with Sharesource were followed in October 2020 and categorized into 2 groups according to the dextrose concentration (group D1.5% and D2.5%). Baseline characteristics, peritoneal membrane characteristics, and daily PD treatment records from Sharesource were obtained. We compared UF under the different conditions.Results: Multivariate linear regression revealed that the mean fill volume (FV) per cycle (p=0.006) and dextrose concentration (p=0.000) were independent predictors of UF. The mean night UF per cycle, the mean night UF corrected by FV per cycle, and the mean night UF corrected by FV and dwelling time (DT) per cycle were 95.8 ml, 5.5%, and 5.0 ‱/minutes in group D1.5% and 220.3 ml, 12.0%, and 11.6 ‱/minutes in group D2.5%, respectively. After an approximately 120-minute DT, there was a trend toward higher UF in the low peritoneal permeability group and lower UF in the high peritoneal permeability group.Conclusion: This retrospective study presents precise UF measurements with two solutions at different dextrose concentrations and four peritoneal transport levels. UF is positively correlated with DT and FV of the dialysate within a reasonable range. High peritoneal permeability is associated with decreased UF, and low peritoneal permeability requires a longer DT to reach the maximal UF.

DESIGN AND TEST OF AIR-SUCTION PEPPER SEED METERING DEVICE BASED ON AIR SUPPLY AND QUANTITATIVE SEED SUPPLY

In order to solve the problem that the current precision seeder has difficulty in precision sowing pepper seeds, an air-suction pepper seed metering device based on air supply and quantitative seed supply was developed. Combined with its basic structure and working principle, the CFD-DEM coupling method was used for analysis, and the best combined hole parameters were obtained. A single factor experiment with the pass rate, replay rate, and missed rate as experimental indicators was designed. Regression model was established to obtain a reasonable range of each parameter. The results showed that when the speed of the drum barrel was 28.65r/min and the working negative pressure was 4.40kPa, the seeding pass rate of the seed meter was 91.32%, the replay rate was 4.51%, and the missed rate was 4.17%. The comprehensive performance index was better.