Evaluation of EWMA Control Charts for Monitoring Spread of Transformed Observations of COVID-19 in India

Singh, Brijesh; Madhusudan, J V; Tiwari, Abhay Kumar; Singh, Sandeep; Das, Utpal Dhar

doi:10.9734/ajrid/2020/v5i230165

Cited by 7 publications

(6 citation statements)

References 13 publications

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“…We used the control limits of the EWMA chart for detecting a mean shift as follow: Where, C is the mean, UCL is the upper control limit, LCL is the lower control limit, σ is the process standard deviation, ρ is the width of the boundary of the control and EWMA chart values are computed by using the R package “qcc . ” 25…”

Section: Methodsmentioning

confidence: 99%

SARS-CoV-2 infection dynamics and genomic surveillance reveals early variant transmission in urban wastewater

Lamba

Sutharan

Daroch

et al. 2022

Preprint

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Environmental surveillance (ES) of a pathogen is crucial for understanding the community load of disease. As an early warning system, ES for SARS–CoV–2 has complemented routine diagnostic surveillance by capturing near real–time virus circulation at a population level. In this longitudinal study in 28 sewershed sites in Bangalore city, we quantified SARS–CoV–2 RNA to track infection dynamics and provide evidence of change in the relative abundance of emerging variants. We describe an early warning system using the exponentially weighted moving average control chart and demonstrate how SARS–CoV–2 RNA concentrations in wastewater correlated with clinically diagnosed new COVID–19 cases, with the trends appearing 8–14 days earlier in wastewater than in clinical data. This was further corroborated by showing that the estimated number of infections is strongly correlated with SARS–CoV–2 RNA copies detected in the wastewater. Using a deconvolution matrix, we detected emerging variants of concern up to two months earlier in wastewater samples. In addition, we found a huge diversity in variants detected in wastewater compared to clinical samples. Our study highlights that quantifying viral titres, correlating it with a known number of cases in the area, and combined with genomic surveillance helps in tracking VOCs over time and space, enabling timely and making informed policy decisions.

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Section: Methodsmentioning

confidence: 99%

SARS-CoV-2 infection dynamics and genomic surveillance reveals early variant transmission in urban wastewater

Lamba

Sutharan

Daroch

et al. 2022

Preprint

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“…For other works that use SPC tools to analyze data from COVID-19 global pandemic, see, for instance. [46][47][48] COVID-19 is a respiratory disease that affects different people in different ways. Most people infected with the virus will experience mild to moderate respiratory illness, recovering without requiring specific treatments.…”

Section: Real Datamentioning

confidence: 99%

“…The idea is to illustrate SPC tools for monitoring routine surveillance on diseases. For other works that use SPC tools to analyze data from COVID‐19 global pandemic, see, for instance 46–48 …”

Section: Applicationsmentioning

confidence: 99%

Statistical process control of overdispersed count data based on one‐parameter Poisson mixture models

Jesus

Ferreira

Boaventura

et al. 2022

Quality & Reliability Eng

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The Poisson distribution is a discrete model widely used to analyze count data. Statistical control charts based on this distribution, such as the c$c$ and u$u$ charts, are relatively well‐established in the literature. Nevertheless, many studies suggest the need for alternative approaches that allow for modeling overdispersion, a phenomenon that can be observed in several fields, including biology, ecology, healthcare, marketing, economics, and industry. The one‐parameter Poisson mixture distributions, whose literature is extensive and essential, can model extra‐Poisson variability, accommodating different overdispersion levels. The distributions belonging to this class of models, including the Poisson‐Lindley (PL), Poisson‐Shanker (PSh), and Poisson‐Sujatha (PSu) models, can thus be used as interesting alternatives to the usual Poisson and COM‐Poisson distributions for analyzing count data in several areas. In this paper, we consider the class of probabilistic models mentioned above (as well as the cited three members of such a class) to develop novel and useful statistical control charts for counting processes, monitoring count data that exhibit overdispersion. The performance of the so‐called one‐parameter Poisson mixture charts, namely the PLc$\text{PL}_c$‐PLu$\text{PL}_u$, PShc$\text{PSh}_c$‐PShu$\text{PSh}_u$, and PSuc$\text{PSu}_c$‐PSuu$\text{PSu}_u$ charts, is measured by the average run length in exhaustive numerical simulations. Some data sets are used to illustrate the applicability of the proposed methodology.

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“…Microalgae are a common and cost-effective polishing step removing nutrients, xenobiotics, and heavy metals from wastewaters foregoing the use of sterile media (Atiku et al, 2016;Beltrán-Rocha et al, 2017;Bohutskyi et al, 2015;Chew et al, 2018;Chiu et al, 2015;de Melo et al, 2018;Fernández-Linares et al, 2017;Gonçalves, Pires, & Simões, 2017;Guldhe et al, 2017;Khan et al, 2019;Kotteswari, Murugesan, & R, 2012;Maizatul et al, 2017;Moreno García et al, 2020;Pahazri et al, 2016;Posadas et al, 2014;Renuka et al, 2015;Singh, Tiwari, & Das, 2016;Solmaz & Mustafa, 2019;Ting et al, 2017;Wang et al, 2016), thriving under stress conditions whilst maintaining their productivity (Ansari et al, 2020). Their photosynthetic activity enables them to sequestrate carbon and decreases wastewater organic and inorganic loads, resulting in biomass that can be either used as a biofertilizer or further processed into biofuels and other products.…”

Section: Introductionmentioning

confidence: 99%

“…Their photosynthetic activity enables them to sequestrate carbon and decreases wastewater organic and inorganic loads, resulting in biomass that can be either used as a biofertilizer or further processed into biofuels and other products. Consequently, eutrophication can be prevented (Amit & Ghosh, 2018;Bohutskyi et al, 2015;Chiu et al, 2015;Gani et al, 2015;Guldhe et al, 2017;Khan et al, 2019;Kotteswari et al, 2012;Rawat et al, 2011;Renuka et al, 2015;Singh et al, 2016) making phycoremediation a very promising technique for mitigating pollution and environmental impacts (Akthar et al, 2017;Atiku et al, 2016;Beltrán-Rocha et al, 2017;Bohutskyi et al, 2015;Chew et al, 2018;Chiu et al, 2015; de Melo et al, 2018;Fernández-Linares et al, 2017;Gonçalves et al, 2017;Guldhe et al, 2017;Kotteswari et al, 2012;Maizatul et al, 2017;Moreno García et al, 2020;Pahazri et al, 2016;Posadas et al, 2014;Renuka et al, 2015;Singh et al, 2016;Solmaz & Mustafa, 2019;Ting et al, 2017;Wang et al, 2016).…”

Section: Introductionmentioning

confidence: 99%

Mixotrophic microalgal mixed cultures for cheese whey valorization

de Almeida,

Mondini,

Bruant

et al. 2023

Preprint

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Microalgae cultivation, and phycoremediation, can be a polishing step in wastewater treatment. Depending on the stream utilized for microalgal cultivation, biomass can be contaminated with considerable quantities of heavy metals and xenobiotics. Given the economic value of microalgae bioproducts, we suggest coupling anaerobic fermentation with microalgae mixotrophic growth. Cheese whey, a product from cheese production, has a 2022 forecast production of 160.7 million m3 year-1 in which about 66.5 million m3y-1is used as animal feed, fertilizers or illegally discharged causing eutrophication. Anaerobic fermentation of cheese whey produces volatile fatty acids (VFAs) such as acetate which serves as an organic carbon source for photoorganoheterotrophic microalgal biomass growth. Our work selected three organic sources derived from cheese whey: 40% demineralized whey powder (WPC40), lactose, and acetate. In photolitoautotrophic conditions, green phototrophic growth was successful. In batch tests, acetate was the best organic carbon source among photoorganoheterotrophs with a higher yield of 1.15 mg VSS mg Carbon-1(C) in anaerobic conditions. Also, acetate uptake was thought to be via the glyoxylate cycle. When upscaling the experiment in a chemostat, a lower dilution rate of 0.17 d-1was more suitable for green photoorganoheterotrophs selection, as they were not washed out in the process. These findings show that acetate uptake by microalgae in mixotrophic regimes must be better understood as well as reinforce the advantages of coupling microalgal biomass growth with cheese whey acidogenic fermentation, avoiding contaminations as in phycoremediation processes and fully valorizing cheese whey.

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Evaluation of EWMA Control Charts for Monitoring Spread of Transformed Observations of COVID-19 in India

Cited by 7 publications

References 13 publications

SARS-CoV-2 infection dynamics and genomic surveillance reveals early variant transmission in urban wastewater

SARS-CoV-2 infection dynamics and genomic surveillance reveals early variant transmission in urban wastewater

Statistical process control of overdispersed count data based on one‐parameter Poisson mixture models

Mixotrophic microalgal mixed cultures for cheese whey valorization

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