scholarly journals Estimation of production consistency of diphtheria, tetanus, and pertussis components of the DTP vaccine using Shewhart charts

2021 ◽  
Vol 21 (4) ◽  
pp. 256-265
Author(s):  
I. A. Alekseeva ◽  
O. V. Perelygina ◽  
E. D. Kolyshkina

The Russian Federation puts special emphasis on vaccination-related issues, in accordance with the WHO recommendations. The fact that vaccination, in particular with the diphtheria, tetanus, and pertussis vaccine (DTP vaccine), covers large population groups, accounts for the relevance of research aimed at improving the quality of vaccines. One of the ways to produce vaccines of assured quality is to maintain consistent manufacturing processes that ensure consistency of product characteristics. The stability of the technological processes may be assessed using Shewhart charts. The aim of the study was to assess the production consistency of diphtheria, tetanus, and pertussis components of DTP vaccine using Shewhart control charts. Materials and methods: the study used data from 60 batch summary protocols of a Russian-produced DTP vaccine that were submitted to the Testing Centre of the Scientific Centre for Expert Evaluation of Medicinal Products from September 2017 until April 2020. The study assessed one of the main vaccine quality characteristics—specific (protective) activity of diphtheria, tetanus, and pertussis components. Shewhart charts for the diphtheria and tetanus components were constructed based on the manufacturer’s summary protocols, while Shewhart charts for the pertussis component were constructed based on both summary protocols and the results obtained by the Testing Centre during certification of the product batches. The Shewhart charts were used in accordance with the national standards GOST R 50779.42-99 and GOST R ISO 7870-2-2015. Results: a retrospective analysis of R- and X-charts covering a 2.5-year period revealed some characteristic trends in special-cause criteria. The most alarming situation was observed for the production of the diphtheria component. The technological processes were somewhat safer in the case of the tetanus and pertussis components. The production process lacked due statistical control, which is confirmed by the lack of correlation between the results of the pertussis component activity assessment obtained by the manufacturer and the Testing Centre. Conclusions: during the analysed period, the production of the diphtheria, tetanus, and pertussis components of the DTP vaccine was not always consistent. This highlights the need to conduct research aimed at standardisation of both production processes and control test conditions.

2018 ◽  
Vol 18 (4) ◽  
pp. 243-248
Author(s):  
I. A. Alekseeva ◽  
O. V. Perelygina ◽  
E. D. Kolyshkina

WHO experts attribute the resurgence of whooping cough to the wide use of acellular pertussis vaccines (aPs) as components of combination products. In this regard, WHO encourages countries that have not yet switched to the use of aPs to continue to use whole-cell pertussis vaccines (wPs) for primary vaccination. The experience of using pertussis vaccines has shown that companies do not always produce highly efficacious products. The use of statistical methods of samples quality control helps to ensure consistency of the technological process, which results in the production of more homogeneous products, and rules out the possibility of producing low-quality products. This paper presents the results of retrospective evaluation of the consistency of the wP (as a pertussis component of the DTP vaccine) production using Shewhart control charts. It was shown that at some points in time during the analyzed period from January 2017 until March 2018 the technological process of the company lacked proper statistical control. This increased the risk of producing non-uniform and defective products. In order to improve the quality and consistency of pertussis component batches, the company’s quality control and quality assurance services should make extensive use of Shewhart charts on a real-time basis.


2014 ◽  
Vol 34 (4) ◽  
pp. 770-779 ◽  
Author(s):  
Fábio Orssatto ◽  
Marcio A. Vilas Boas ◽  
Ricardo Nagamine ◽  
Miguel A. Uribe-Opazo

The current study used statistical methods of quality control to evaluate the performance of a sewage treatment station. The concerned station is located in Cascavel city, Paraná State. The evaluated parameters were hydrogenionic potential, settleable solids, total suspended solids, chemical oxygen demand and biochemical oxygen demand in five days. Statistical analysis was performed through Shewhart control charts and process capability ratio. According to Shewhart charts, only the BOD(5.20) variable was under statistical control. Through capability ratios, we observed that except for pH the sewage treatment station is not capable to produce effluents under characteristics that fulfill specifications or standard launching required by environmental legislation.


2018 ◽  
Vol 20 (20) ◽  
pp. 26-31 ◽  
Author(s):  
Krzysztof Knop

Abstract The article presents the results of the use of SPC tools, i.e. control charts and indicators of the qualitative capability to assess the stability and capability of the production process of rolled products - I-sections. Statistical analysis of the collected data regarding the selected feature of the analysed product - the width of the foot, and the normality of the distribution were done, which showed that the obtained distribution of measurement results is not a normal distribution. As a result, appropriate SPC procedures for non-normal distribution were used. The Pareto-Lorenzo diagram and FMEA method were also used to obtain information about the structure of non-conformities of the analysed product and the level of risk associated with them. This information was used to propose corrective actions and improve the production process of rolled products.


2014 ◽  
Vol 644-650 ◽  
pp. 1019-1022
Author(s):  
Ya Wei Zhang ◽  
Dong Wang ◽  
Shu Mao Wang

To evaluate the noise and emissions of combine harvest meet the national standards or not, a noise and emissions testing and analyzing system was developed based on virtual instrument. A high precision digital noise level meter and an opacimeter were connected to a computer via a RS232 cable, and used to detect the noise and emissions of a working combine harvester respectively. A measurement and control software was developed to collect, process and analysis the measured data automatically in real-time, and the experimental data also could be stored and printed when necessary. The analyzed results were shown on the software interface by curves and LED. To verify the stability and reliability of the system, a serial of tests were made with a Xinjiang-2A combine harvester, the results showed that this detection system meet the need of different kinds of practical applications.


Irriga ◽  
2016 ◽  
Vol 21 (4) ◽  
pp. 631-647 ◽  
Author(s):  
Jorge Tomoyoshi Tamagi ◽  
Miguel Angel Uribe Opazo ◽  
Jerry Adriani Johann ◽  
Marcio Antonio Vilas Boas

UNIFORMIDADE DE DISTRIBUIÇÃO DE ÁGUA DE IRRIGAÇÃO POR ASPERSORES COMPENSANTES E NÃO COMPENSANTES EM DIFERENTES ALTURAS  JORGE TOMOYOSHI TAMAGI1; MIGUEL ANGEL URIBE-OPAZO2; JERRY ADRIANI JOHANN2 E MARCIO ANTONIO VILAS BOAS2 1 Universidade Estadual do Oeste do Paraná - UNIOESTE, Doutorando em Engenharia Agrícola no Programa de Pós-Graduação em Engenharia Agrícola – PGEAGRI. Rua Universitária, 2069 – Jd. Universitário – Caixa Postal 711 – CEP 85819-110 – Cascavel – PR, e-mail: [email protected] UNIOESTE, campus de Cascavel – PR, professores e pesquisadores do PGEAGRI, e-mails: [email protected]; [email protected]; [email protected].  1 RESUMO Este trabalho tem como finalidade contribuir para o desenvolvimento de técnicas adequadas para avaliação de sistemas de irrigação por aspersão, considerando que a uniformidade de distribuição da água afeta diretamente a lâmina bruta de irrigação. O experimento foi conduzido na região Norte de Cascavel, Paraná, (24º 55’ 04” latitude Sul, 53º 28’ 31” longitude Oeste e altitude de 785 m). Foram utilizadas duas parcelas de 10 x 10 m, denominadas S1 e S2, modificando-se somente a altura dos aspersores de 1,5 m para 1,0 m, respectivamente. Em cada parcela foram instalados 100 coletores, 4 aspersores super 10 bocal azul, compensante e, após 32 ensaios, foram substituídos por 4 aspersores super 10 bocal azul, não compensante. Foram determinados os seguintes coeficientes: Uniformidade de Christiansen, Uniformidade de Distribuição e Uniformidade Estatístico. Foram realizados estudos de inferência estatística e criadas cartas de controle para a análise do controle estatístico do processo, além dos índices de capacidade de processo (Cp) e desempenho do processo (Cpk). Os resultados mostraram que o aspersor compensante apresentou melhor desempenho à altura de 1,5 m (C-1,5 m) e que, entre as alturas de 1,0 m e 1,5 m, as melhores uniformidades de distribuição de água ocorreram na altura de 1,5 m. Palavras-chave: inferência estatística; cartas de controle; capacidade de processo.  TAMAGI, J. T.; URIBE-OPAZO, M. A.; JOHANN J. A.; VILAS BOAS, M. A. IRRIGATION WATER DISTRIBUTION UNIFORMITY BY COMPENSATING AND NON-COMPENSATING SPRINKLERS AT DIFFERENT HEIGHTS  2 ABSTRACT The uniformity of water application is an important factor to be considered in the assessment of sprinkler irrigation systems, since it directly affects gross irrigation depth, This work is a contribution for the development of appropriate techniques for assessment of results to improve the system. This trial was conducted  in the Northern region of Cascavel-PR (24º 55' 04" S, 53º 28' 31" W). Two 10 x 10 m plots were used and described as S1 and S2, according to the heights’ change of sprinklers, from 1.5 to 1.0 m, respectively. There were 100 collectors in each plot, plus 4 Super 10-blue-nozzle pressure compensating sprinklers, and, after 32 essays, they were replaced by 4 Super 10-blue-nozzle non pressure compensating sprinklers. The following coefficients were determined: Christiansen uniformity coefficient (CUC), coefficient of uniformity of distribution (CUD) and statistical uniformity coefficient (SUC). Statistical inference studies were carried out and control charts were generated to analyze the statistical control of the process, as well as Cp and Cpk indices. The results showed the best performance with the pressure compensating sprinklers irrigation at 1.5 m high (C-1.5 m) and that among the 1.0 m and 1.5 m heights the best water distribution uniformity was with the 1.5 m height. Keywords: Statistical analysis; Control Charts; Process Capacity.


Author(s):  
Dereje Girma ◽  
Omprakash Sahu

Identifying the presence and understanding the causes of process variability are key requirements for well controlled and quality manufacturing. This pilot study demonstrates the introduction of Statistical Process Control (SPC) methods to the spinning department of a textile manufacturing company. The methods employed included X Bar and R process control charts as well as process capability analysis. Investigation for 29 machine processes identified that none were in statistical control. Recommendations have been made for a repeat of the study using validated data together with practical application of SPC and control charts on the shop floor and extension to all processes within the factory.


Author(s):  
M. XIE ◽  
T. N. GOH ◽  
H. WIKLUND ◽  
X. Y. TANG

Statistical control charts have been successfully used in industry for monitoring stable processes. However, processes with uncontrollable but acceptable trend are common in practice. One typical example is the wear process of cutting tools. Conventional control charts may not serve the purpose of process monitoring. In this paper, a forecast-based technique using Double Exponential Smoothing is proposed. It eliminates the trend component, and control charts are applied to the residuals. Furthermore, a procedure based on double control lines is suggested and adopted in tool wear process monitoring to integrate statistical and engineering properties for better decision making on tool wear-out. Other than the monitoring of tool wear process, the method can be used for better monitoring of other processes with trend. An actual tool wear data set is used as illustration.


Irriga ◽  
2018 ◽  
Vol 1 (01) ◽  
pp. 56 ◽  
Author(s):  
JIAM PIRES FRIGO ◽  
MARCIO ANTONIO VILAS BOAS ◽  
JIANICE PIRES FRIGO ◽  
ELISANDRO PIRES FRIGO

COMPARAÇÃO ENTRE GRÁFICOS DE CONTROLE DE SHEWHART, CUSUM E MMEP NO PROCESSO DE IRRIGAÇÃO POR ASPERSÃO CONVENCIONAL  JIAM PIRES FRIGO1; MARCIO ANTONIO VILAS BOAS2; JIANICE PIRES FRIGO2 E ELISANDRO PIRES FRIGO3 1 Instituto Latino-Americano de Tecnologia, Infraestrutura e Território - ILATIT (UNILA), Av. Tancredo Neves, 3838 - Porto Belo, CEP 85867-970, Foz do Iguaçu, PR, Fone (45)99993 4783, e‑mail:[email protected] Centro de Ciências Exatas e Tecnológicas, Programa de Pós Graduação em Engenharia Agrícola (Unioeste), R. Universitária, 2069 - Jardim Universitário CEP 85819-110, Cascavel-PR3 Universidade Federal do Paraná, Campus Palotina  R. Pioneiro, 2153 - Dallas, CEP 85950-000, Palotina-PR  1 RESUMO O objetivo deste estudo foi comparar os resultados da utilização dos gráficos de controle de Shewhart para medidas individuais, com os gráficos de controle média móvel exponencialmente ponderada (MMEP) e soma cumulativa (CUSUM), aplicados no controle de qualidade da irrigação. Foram realizados 60 ensaios de irrigação em um sistema por aspersão convencional. As análises do processo de controle de qualidade do sistema de irrigação foram realizadas por meio dos gráficos de Shewhart (Xbarra), gráficos MMEP e CUSUM. Todos os procedimentos para os ensaios de uniformidade da irrigação foram realizados conforme recomendação NBR ISO 7749-2 (ABNT, 2000). Para a avaliação do sistema foi utilizado o Coeficiente de Uniformidade de Christiansen (CUC). O gráfico de controle MMEP apresentou-se bastante suscetível quando utilizado em dados auto correlacionados, com ocorrências de alarmes falsos. Para dados independentes (pelo modelo ARIMA), o gráfico CUSUM foi mais sensível ao detectar as variações ocorridas na irrigação devido à velocidade do vento, quando comparado aos gráficos MMEP e Shewhart para os mesmos dados. Na irrigação por aspersão, relacionando CUC com velocidade do vento, o gráfico de Shewhart foi mais indicado pela simplicidade, robustez e facilidade de interpretação, mesmo na presença de dados que violam a suposição de independência. Os gráficos de controle de Shewhart, MMEP e CUSUM provaram serem ótimas ferramentas estatísticas no estudo da irrigação por aspersão convencional, demonstrando muito bem a variabilidade no processo. Palavras-Chave: água, vento, Coeficiente de Christiansen, Controle de qualidade.  FRIGO, J.P.; VILAS BOAS, M.A.; FRIGO, J.P.; FRIGO, E.P.COMPARISON BETWEEN SHEWHART CONTROL CHARTS, CUSUM AND MMEP IN PROCESS OF CONVENTIONAL IRRIGATION SPRINKLER  2 ABSTRACT This study aimed to compare the results of Shewhart control charts use for individual measures with exponentially weighted moving average (MMEP) and cumulative sum (CUSUM) control charts applied in quality control of conventional sprinkler irrigation. Sixty irrigation trials were set up in a conventional sprinkler system. The analyses of the quality control process of the irrigation system were performed by means of Shewhart charts (Xbarra) charts, MMEP and CUSUM. All procedures for testing uniformity of irrigation were performed as recommended by ISO 7749-2 (ABNT, 2000). For the evaluation of the system, it was used Christiansen Uniformity Coefficient (CUC). The control chart MMEP showed to be quite susceptible when used in auto correlated data with instances of false alarms. For independent data (the ARIMA model), the CUSUM tabular chart was more sensitive to detect variations in irrigation due to wind speed, when compared to MMEP and Shewhart charts for the same data. In sprinkler irrigation, relating CUC with wind speed, the Shewhart chart was better due to such features as simplicity, robustness and easiness of interpretation, even in the presence of data that violate the assumption of independence. The Shewhart control charts, CUSUM and MMEP statistics proved to be great tools in the study of irrigation sprinkler, demonstrating very well the variability in the process. Keywords: water, wind, Christiansen coefficient, control charts, Quality control.


2020 ◽  
Vol 49 (2) ◽  
pp. 20190229
Author(s):  
Arezou Shahbazi Moghaddam ◽  
Joshua C Kats ◽  
Rujuta Katkar ◽  
Anibal R Diogenes ◽  
Chih-Ko Yeh ◽  
...  

Objectives: To implement the quality control assurance protocol (including the re-establishment of baseline data from 2016) to monitor the stability of image quality of CBCT machines located within the UT Health San Antonio School of Dentistry. Methods and materials: Five CBCT machines ProMax 3D Mid® (Planmeca Oy, Helsinki, Finland), 3D Accuitomo XYZ Slice View Tomograph® (Model MCT-1, Type EX-1F8; Fushimi-ku, Kyoto: J. Morita Mfg. Corp), Veraviewepocs 3D (Model R100; Fushimi-ku, Kyoto: J. Morita Mfg. Corp), PreXion3D Excelsior® (PreXion, San Mateo, CA), and i-CAT FLX Series® (Imaging Sciences International, Hatfield, PA) were tested for Artifact, Contrast-to-Noise Ratio, Noise, Spatial Resolution, and Contrast Resolution using a custom insert configuration in the SEDENTEXCT IQ phantom. Results: Four-scan benchmark mean values for Artifact, Contrast-to-Noise, Noise, Spatial Resolution, and Contrast Resolution were determined for the five machines tested with associated alert and action level thresholds calculated. Conclusion: This newly developed QA protocol established image quality baseline values. Recommended tests, frequency, and actions levels have been updated and control charts established for future trend analysis to enable proper implementation of a QA protocol monitoring CBCT machines at UT health San Antonio.


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