scholarly journals Delayed Modeling Approach to Forecast the Periodic Behavior of SARS-2

2021 ◽  
Vol 7 ◽  
Author(s):  
Zhenhua Yu ◽  
Ayesha Sohail ◽  
Alessandro Nutini ◽  
Robia Arif
Keyword(s):  
Time Delay ◽  
Dynamic Behavior ◽  
Control Strategies ◽  
The State ◽  
Periodic Behavior ◽  
Transmission Rates ◽  
Modeling Approach ◽  
Key Players ◽  
Precautionary Measures

The ongoing threat of Coronavirus is alarming. The key players of this virus are modeled mathematically during this research. The transmission rates are hypothesized, with the aid of epidemiological concepts and recent findings. The model reported is extended, by taking into account the delayed dynamics. Time delay reflects the fact that the dynamic behavior of transmission of the disease, at time t depends not only on the state at time t but also on the state in some period τ before time t. The research presented in this manuscript will not only help in understanding the current threat of pandemic (SARS-2), but will also contribute in making precautionary measures and developing control strategies.

scholarly journals Nonlinear vibrations and time delay control of an extensible slowly rotating beam

2020 ◽  
Author(s):  
Jerzy Warminski ◽  
Lukasz Kloda ◽  
Jaroslaw Latalski ◽  
Andrzej Mitura ◽  
Marcin Kowalczuk
Keyword(s):  
Time Delay ◽  
Control Strategies ◽  
Vibration Reduction ◽  
Least Action ◽  
Active Elements ◽  
Principle Of Least Action ◽  
Second Mode ◽  
Delay Control ◽  
Speed Range ◽  
System With Time Delay

AbstractNonlinear dynamics of a rotating flexible slender beam with embedded active elements is studied in the paper. Mathematical model of the structure considers possible moderate oscillations thus the motion is governed by the extended Euler–Bernoulli model that incorporates a nonlinear curvature and coupled transversal–longitudinal deformations. The Hamilton’s principle of least action is applied to derive a system of nonlinear coupled partial differential equations (PDEs) of motion. The embedded active elements are used to control or reduce beam oscillations for various dynamical conditions and rotational speed range. The control inputs generated by active elements are represented in boundary conditions as non-homogenous terms. Classical linear proportional (P) control and nonlinear cubic (C) control as well as mixed ($$P-C$$ P - C ) control strategies with time delay are analyzed for vibration reduction. Dynamics of the complete system with time delay is determined analytically solving directly the PDEs by the multiple timescale method. Natural and forced vibrations around the first and the second mode resonances demonstrating hardening and softening phenomena are studied. An impact of time delay linear and nonlinear control methods on vibration reduction for different angular speeds is presented.

Comprehensive Analysis for Influence of Controllable Damper Time Delay on Semi-Active Suspension Control Strategies

2017 ◽  
Vol 139 (3) ◽  
Author(s):  
Yechen Qin ◽  
Feng Zhao ◽  
Zhenfeng Wang ◽  
Liang Gu ◽  
Mingming Dong
Keyword(s):  
Time Delay ◽  
Dynamic Characteristics ◽  
Ride Comfort ◽  
Hybrid Control ◽  
Sliding Mode ◽  
Control Strategies ◽  
Active Suspension ◽  
Test System ◽  
Suspension Control ◽  
Simulation Results

This paper presents a comprehensive comparison and analysis for the effect of time delay on the five most representative semi-active suspension control strategies, and refers to four unsolved problems related to semi-active suspension performance and delay mechanism that existed. Dynamic characteristics of a commercially available continuous damping control (CDC) damper were first studied, and a material test system (MTS) load frame was used to depict the velocity-force map for a CDC damper. Both inverse and boundary models were developed to determine dynamic characteristics of the damper. In addition, in order for an improper damper delay of the form t+τ to be corrected, a delay mechanism of controllable damper was discussed in detail. Numerical simulation for five control strategies, i.e., modified skyhook control SC, hybrid control (HC), COC, model reference sliding mode control (MRSMC), and integrated error neuro control (IENC), with three different time delays: 5 ms, 10 ms, and 15 ms was performed. Simulation results displayed that by changing control weights/variables, performance of all five control strategies varied from being ride comfort oriented to being road handling oriented. Furthermore, increase in delay time resulted in deterioration of both ride comfort and road handling. Specifically, ride comfort was affected more than road handling. The answers to all four questions were finally provided according to simulation results.

scholarly journals New delay-dependent observer-based control for uncertain stochastic time-delay systems

2019 ◽  
Vol 2019 (1) ◽  
Author(s):  
Xiu-feng Miao ◽  
Long-suo Li
Keyword(s):  
Time Delay ◽  
The State ◽  
Delay Systems ◽  
Linear Matrix ◽  
Time Delay Systems ◽  
Parameter Uncertainties ◽  
Noise Disturbances ◽  
System States ◽  
Delay Dependent ◽  
Stochastic Time

AbstractThis paper considers the problem of estimating the state vector of uncertain stochastic time-delay systems, while the system states are unmeasured. The system under study involves parameter uncertainties, noise disturbances and time delay, and they are dependent on the state. Based on the Lyapunov–Krasovskii functional approach, we present a delay-dependent condition for the existence of a state observer in terms of a linear matrix inequality. A numerical example is exploited to show the validity of the results obtained.

Measurement of the Pulverized Coal Concentration by Measuring the Time Delay of Ultrasonic with Digital Correlation Method

2013 ◽  
Vol 333-335 ◽  
pp. 359-364
Author(s):  
Ke Wang
Keyword(s):  
Time Delay ◽  
Power Plant ◽  
Correlation Method ◽  
The State ◽  
Pulverized Coal ◽  
Measuring System ◽  
Digital Correlation ◽  
Coal Boiler ◽  
Key Parameter

The pulverized coal concentration in blast pipe in front of firebox is one key parameter in coal boiler used in a power plant; it will affect the state of burning in firebox. This paper proposes a new digital correlation method to measure the time delay of ultrasonic for measuring the pulverized coal concentration. The principle of measurement is discussed in detail and the measuring system is designed.

Surveillance-based estimation of the malaria disease burden in a low endemic state of Punjab, India, targeted for malaria elimination

2021 ◽  
Author(s):  
Jaspreet Kaur ◽  
Taruna Kaura ◽  
Ayush Sharma ◽  
Ashish Kumar ◽  
M K Pangotra ◽  
...  
Keyword(s):  
Malaria Elimination ◽  
Control Strategies ◽  
The State ◽  
Primary Data ◽  
Effective Control ◽  
Malaria Surveillance ◽  
Weighted Estimates ◽  
Malaria Burden ◽  
Routine Surveillance ◽  
Malaria Trends

Abstract Background The state of Punjab in India qualifies for malaria elimination because the number of cases reported through routine surveillance is in decline. However, surveillance system prevalence mainly provides malaria trends. Therefore, a prospective epidemiological study was designed to estimate the malaria burden in the state. Methods District-wise annual parasite incidence (API) was used for identification of three strata, representing high, moderate and low API zones. A total of 0.9 million people from nine districts was under malaria surveillance for 1 y. The weighted estimates of API for the three regions was calculated and combined to give an estimate of API for the total population of the state. Results Based upon the primary data generated, malaria cases from high, moderate and low malaria-endemic areas were estimated to be 3727, 904 and 106, respectively. Further, the total number of malaria cases in the state was estimated to be 4737 (95% CI 4006 to 5469) cases per annum. Conclusion Actual burden of malaria in the state of Punjab, India, is about seven to eight times higher than that reported by routine surveillance activities. However, the state still qualifies for malaria elimination but needs vigorous efforts to strengthen the active surveillance and reporting system along with implementation of effective control strategies to achieve malaria elimination.

A self-oscillating gel system with complex dynamic behavior based on a time delay between the oscillations

Soft Matter ◽  
2021 ◽  
Author(s):  
Xiuchen Li ◽  
Jie Li ◽  
Zhaohui Zheng ◽  
Jinni Deng ◽  
Yi Pan ◽  
...  
Keyword(s):  
Time Delay ◽  
Dynamic Behavior ◽  
Experimental Studies ◽  
Complex Dynamic ◽  
Chemical Oscillation ◽  
Mechanical Oscillation ◽  
Behavior Based ◽  
Gel System

The time delay existing between the chemical oscillation and mechanical oscillation (C-M delay) in a self-oscillating gel (SOG) system is observable in previous experimental studies. However, how the C-M delay...

Implementasi Kebijakan Pendidikan (Budaya) Bela Negara: Studi Kasus SD Katolik Karya Toboali, Kepulauan Bangka Belitung

Inovasi ◽  
2021 ◽  
Vol 18 (2) ◽  
pp. 149-167
Author(s):  
Fatkhuri Fatkhuri
Keyword(s):  
Elementary School ◽  
School Culture ◽  
Defense Policy ◽  
The State ◽  
Main Character ◽  
Defense Behavior ◽  
Modeling Approach ◽  
State Defense ◽  
Assessment Results ◽  
Descriptive Qualitative

This study aims to grasp the policy of state defense which embedded through the form of school culture which plays an important role to shape the character of state defense in Katolik Karya, Toboali Elementary School, Bangka Belitung. This also seeks to capture how state defense culture is effectivelly implemented to support the students’ character. This study uses descriptive qualitative, in which data and information are obtained through interviews, questionnaires, and documents involving principals, teachers, education staff, and students. This study found that the school already has developed policy to instill a state defense culture which is introduced by the Tunas Karya Foundation. The state defense policy is developed through a set of values which are arranged in the ten main character as a genuine of cultural product to form of student character. Schools conduct a state defense policy through habituation with a nurturing and modeling approach by teachers. This study also shows that the habituation of the ten main character values in making state defense behavior is quite effective. Based on the assessment results, the data shows that the majority of students have regularly employed the habituation of the state defense with average marks at 82 point.

Chaos Control for a Fractional-Order Jerk System via Time Delay Feedback Controller and Mixed Controller

2021 ◽  
Vol 5 (4) ◽  
pp. 257
Author(s):  
Changjin Xu ◽  
Maoxin Liao ◽  
Peiluan Li ◽  
Lingyun Yao ◽  
Qiwen Qin ◽  
...  
Keyword(s):  
Time Delay ◽  
Fractional Order ◽  
Chaos Control ◽  
Chaotic Behavior ◽  
Control Strategies ◽  
Feedback Controller ◽  
Research Approach ◽  
Controlling Chaos ◽  
The Stability ◽  
Jerk System

In this study, we propose a novel fractional-order Jerk system. Experiments show that, under some suitable parameters, the fractional-order Jerk system displays a chaotic phenomenon. In order to suppress the chaotic behavior of the fractional-order Jerk system, we design two control strategies. Firstly, we design an appropriate time delay feedback controller to suppress the chaos of the fractional-order Jerk system. The delay-independent stability and bifurcation conditions are established. Secondly, we design a suitable mixed controller, which includes a time delay feedback controller and a fractional-order PDσ controller, to eliminate the chaos of the fractional-order Jerk system. The sufficient condition ensuring the stability and the creation of Hopf bifurcation for the fractional-order controlled Jerk system is derived. Finally, computer simulations are executed to verify the feasibility of the designed controllers. The derived results of this study are absolutely new and possess potential application value in controlling chaos in physics. Moreover, the research approach also enriches the chaos control theory of fractional-order dynamical system.

scholarly journals Cattle trade between and within biomes in the state of Mato Grosso, Brazil

2018 ◽  
Vol 38 (11) ◽  
pp. 2023-2028
Author(s):  
Rísia L. Negreiros ◽  
José H.H. Grisi-Filho ◽  
Ricardo A. Dias ◽  
Fernando Ferreira ◽  
Valéria S.F. Homem ◽  
...  
Keyword(s):  
Infectious Diseases ◽  
Animal Movement ◽  
Control Strategies ◽  
The State ◽  
Disease Spread ◽  
Mato Grosso ◽  
Movement Data ◽  
Cattle Movements ◽  
Increased Risk ◽  
And Control

ABSTRACT: The analysis of animal movement patterns may help identify farm premises with a potentially high risk of infectious disease introduction. Farm herd sizes and bovine movement data from 2007 in the state of Mato Grosso, Brazil, were analyzed. There are three different biomes in Mato Grosso: the Amazon, Cerrado, and Pantanal. The analysis of the animal trade between and within biomes would enable characterization of the connections between the biomes and the intensity of the internal trade within each biome. We conducted the following analyses: 1) the concentration of cattle on farm premises in the state and in each biome, 2) the number and relative frequency of cattle moved between biomes, and 3) the most frequent purposes for cattle movements. Twenty percent (20%) of the farm premises had 81.15% of the herd population. Those premises may be important not only for the spread of infectious diseases, but also for the implementation of surveillance and control strategies. Most of the cattle movement was intrastate (97.1%), and internal movements within each biome were predominant (88.6%). A high percentage of movement from the Pantanal was to the Cerrado (48.6%), the biome that received the most cattle for slaughter, fattening and reproduction (62.4%, 56.8%, and 49.1% of all movements for slaughter, fattening, and reproduction, respectively). The primary purposes for cattle trade were fattening (43.5%), slaughter (31.5%), and reproduction (22.7%). Presumably, movements for slaughter has a low risk of disease spread. In contrast, movements for fattening and reproduction purposes (66.2% of all movements) may contribute to an increased risk of the spread of infectious diseases.

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