Real-Time Estimation of R0 for COVID-19 Spread

We propose a real-time approximation of R0 in an SIR-type model that applies to the COVID-19 epidemic outbreak. A very useful direct formula expressing R0 is found. Then, various type of models are considered, namely, finite differences, cubic splines, Piecewise Cubic Hermite interpolation and linear least squares approximation. Preserving the monotonicity of the formula under consideration proves to be of crucial importance. This latter property is preferred over accuracy, since it maintains positive R0. Only the Linear Least Squares technique guarantees this, and is finally proposed here. Tests on real COVID-19 data confirm the usefulness of our approach.

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Recursive-Least-Squares-Based Real-Time Estimation of Supercapacitor Parameters

IEEE Transactions on Energy Conversion ◽

10.1109/tec.2016.2521324 ◽

2016 ◽

Vol 31 (2) ◽

pp. 810-812 ◽

Cited By ~ 45

Author(s):

Noam Reichbach ◽

Alon Kuperman

Keyword(s):

Least Squares ◽

Real Time ◽

Time Estimation ◽

Recursive Least Squares ◽

Real Time Estimation

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Real-Time Estimation of Power System Frequency Using Nonlinear Least Squares

IEEE Transactions on Power Delivery ◽

10.1109/tpwrd.2009.2021047 ◽

2009 ◽

Vol 24 (3) ◽

pp. 1021-1028 ◽

Cited By ~ 66

Author(s):

R. Chudamani ◽

Krishna Vasudevan ◽

C. S. Ramalingam

Keyword(s):

Power System ◽

Least Squares ◽

Real Time ◽

Nonlinear Least Squares ◽

Time Estimation ◽

Real Time Estimation ◽

System Frequency

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Real-time estimation method of roll angle based on least squares recursion

MATEC Web of Conferences ◽

10.1051/matecconf/202030605002 ◽

2020 ◽

Vol 306 ◽

pp. 05002

Author(s):

Chen Jingsheng ◽

Li Chuanjun ◽

Hu Peisen

Keyword(s):

Least Squares ◽

Real Time ◽

Least Squares Method ◽

Estimation Method ◽

Time Estimation ◽

Calculation Procedure ◽

Roll Angle ◽

Angle Estimation ◽

Real Time Estimation ◽

High Dynamic

The rotary missile stands a high overload during the launch and has to be powered up after launch, so it is necessary to achieve inflight alignment under high dynamic conditions. As a key technology of inflight alignment, the measurement method of roll angle has attracted more and more attention from researchers. The rotational speed of the rotary missile is very high, and most MIMUs cannot directly measure the roll angle. To solve this problem, this paper proposes a roll angle estimation method based on least squares method, analyzes its principle and derives the calculation procedure. Then on this basis, the roll angle estimation method based on least squares recursion is studied. The principle and calculation procedure of this method are deduced in detail. At last, the simulation experiment on MATLAB is carried out. The results show that this method is simple in calculation, high in accuracy and good in real-time performance, and has great application value.

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Real-time estimation of BDS/GPS high-rate satellite clock offsets using sequential least squares

Advances in Space Research ◽

10.1016/j.asr.2018.04.025 ◽

2018 ◽

Vol 62 (2) ◽

pp. 477-487 ◽

Cited By ~ 7

Author(s):

Wenju Fu ◽

Yuanxi Yang ◽

Qin Zhang ◽

Guanwen Huang

Keyword(s):

Least Squares ◽

Real Time ◽

Time Estimation ◽

High Rate ◽

Satellite Clock ◽

Real Time Estimation

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Real-Time Parameter Estimation of a Dual-Pol Radar Rain Rate Estimator Using the Extended Kalman Filter

Remote Sensing ◽

10.3390/rs13122365 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2365

Author(s):

Wooyoung Na ◽

Chulsang Yoo

Keyword(s):

Kalman Filter ◽

Least Squares ◽

Real Time ◽

Extended Kalman Filter ◽

Rain Rate ◽

Least Squares Method ◽

Time Estimation ◽

Storm Events ◽

Real Time Estimation ◽

Radar Rain Rate

The extended Kalman filter is an extended version of the Kalman filter for a non-linear problem. This study applies this extended Kalman filter to the real-time estimation of the parameters of the dual-pol radar rain rate estimator. The estimated parameters are also compared with those based on the least squares method. As an application example, this study considers four storm events observed by the Beaslesan radar in Korea. The findings derived include, first, that the parameters of the radar rain rate estimator obtained by the extended Kalman filter are totally different from those by the least squares method. In fact, the parameters obtained by the extended Kalman filter are found to be more reasonable, and are similar to those reported in previous studies. Second, the estimated rain rates based on the parameters obtained by the extended Kalman filter are found to be similar to those observed on the ground. Even though the parameters estimated by applying the least squares method are quite different from previous studies as well as those based on the extended Kalman filter, the resulting radar rain rate is found to be quite similar to that based on the extended Kalman filter. In conclusion, the extended Kalman filter can be a reliable method for real-time estimation of the parameters of the dual-pol radar rain rate estimator. The resulting rain rate is also found to be of sufficiently high quality to be applicable for other purposes, such as various flood warning systems.

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A machine for real-time estimation of the tribological characteristics of materials

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2020-86-4-61-65 ◽

2020 ◽

Vol 86 (4) ◽

pp. 61-65

Author(s):

M. V. Abramchuk ◽

R. V. Pechenko ◽

K. A. Nuzhdin ◽

V. M. Musalimov

Keyword(s):

Real Time ◽

Time Estimation ◽

Tribological Characteristics ◽

Continuous Processing ◽

Friction Machine ◽

Dynamic Friction Coefficient ◽

Displacement Sensors ◽

Frictional Interaction ◽

Real Time Estimation ◽

Automated Quality Control

A reciprocating friction machine Tribal-T intended for automated quality control of the rubbing surfaces of tribopairs is described. The distinctive feature of the machine consists in implementation of the forced relative motion due to the frictional interaction of the rubbing surfaces fixed on the drive and conjugate platforms. Continuous processing of the signals from displacement sensors is carried out under conditions of continuous recording of mutual displacements of loaded tribopairs using classical approaches of the theory of automatic control to identify the tribological characteristics. The machine provides consistent visual real time monitoring of the parameters. The MATLAB based computer technologies are actively used in data processing. The calculated tribological characteristics of materials, i.e., the dynamic friction coefficient, damping coefficient and measure of the surface roughness, are presented. The tests revealed that a Tribal-T reciprocating friction machine is effective for real-time study of the aforementioned tribological characteristics of materials and can be used for monitoring of the condition of tribo-nodes of machines and mechanisms.

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