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MONITORAMENTO DO CONTROLE ESTATÍSTICO DO PROCESSO UTILIZANDO FERRAMENTAS ESTATÍSTICAS / MONITORING OF STATISTICAL PROCESS CONTROL USING STATISTICAL TOOLSMartins, Sandro Luís Moresco 14 March 2011 (has links)
Empresa Brasileira de Pesquisa Agropecuária / This study used the data from a tobacco company that monitors its production
process through statistical process control. The objective of this study was to apply
multivariate statistical tools of Statistical Process Control to monitor the efficiency of
the production process of the company under study. This production process consists
of four variables monitored during the manufacture of cigarettes: RDT (Resistence to
Draw), weight, ventilation and circunference. These data were verified using
descriptive statistics, test of normality, univariate R and X-bar charts and correlation
matrix. After observing the instability of the system, the Principal Component Analysis
(PCA) was applied. PCA is an exploratory multivariate analysis technique that aims
at gathering various features of the significant variables in the instability of the
production process. EWMA was then applied on the principal components. An unstable
process presenting too much variability was observed, with several points outside the
bounds of statistical control. This situation presents some problems that may cause
inconvenience and loss to the company. This way, the company should review its
manufacturing process in order to improve its productivity and quality that in turn may
help the company to be more competitive. / O presente estudo utilizou-se dos dados de uma empresa fumageira que
monitora o processo produtivo por meio do controle estatístico do processo.
Objetivou-se a aplicação de ferramentas estatísticas multivariadas de Controle
Estatístico do Processo, para monitorar a eficiência do processo produtivo da
empresa em estudo. Esse processo produtivo é composto de quatro variáveis,
monitoradas na fase de fabricação do cigarro, sendo: RDT (Resistence to Draw),
peso, ventilação e circunferência. Esses dados foram verificados através da
estatística descritiva, Teste de Normalidade, gráficos univariados X-barra e R, e
Matriz de correlação. Após constatada a instabilidade do sistema, aplicou-se Análise
de Componentes Principais ACP, técnica de análise exploratória multivariada com
o objetivo de aglutinar várias características das variáveis significativas na
instabilidade do processo produtivo. Por último, foi aplicado EWMA (Exponentially
Weighted Moving Average - Médias Móveis Exponencialmente Ponderáveis) sobre
as componentes principais. Demonstrou-se um processo instável, apresentando
muita variabilidade, com muitos pontos fora dos limites de controle estatístico. Essa
situação, apresenta alguns problemas, que geram transtornos e prejuízos à
empresa, sendo que a mesma deverá rever seu processo fabril a fim de melhorar a
produtividade e a qualidade, que contribuirá para tornar a empresa mais competitiva.
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Snusförnuft. J A Boman & Co och dess anpassningsförmåga : En företagshistoria om en tobaksfirma i Göteborg år 1847-1915 / J A Boman & Co and its adaptability : A business history about a tobacco company in Gothenburg 1847-1915Winqvist, Camilla January 2014 (has links)
This essay is a business history about the Swedish midsized tobacco company J A Boman & Co, previously Ferd Körner and Körner & Boman, which was part of the blooming tobacco industry in Sweden during the 19th century. One purpose of the essay is to fill a gap within both business history in general and the study of tobacco companies in particular, since they both tend to favor studies on larger companies. The other purpose is to find a methodological way to study a smaller sized, older company with very few sources from the actual company. The essay seeks to answer questions about the company’s production history and how it changed over the years. The study takes use of both qualitative and quantitative methods to examine the company and how it developed over time. It is not an essay deeply embedded in theory, it rather seeks to use different theoretical approaches. One approach is a micro level macro theory, that claims that a company only can be understood through the macro level and that the company, itself being the micro level, can deliver exciting new findings that creates a deeper understanding for the macro level. Throughout the essay, the company’s production statistics are examined, and combined with newspaper articles, letters and previous academic works within the field, the essay closes in on answers to the questions that were introduced in the beginning. The examination of the company finds that the midsized company managed to survive through adaptability to its time and circumstances. The company chose to sell their products through merchants instead of directly to the consumers, unlike most of the other tobacco companies at the time. The methodological problem, which was part of the essay’s purpose, was resolved by the combined method described earlier in the abstract, although the essay would admittedly have been better if there had been some papers left from the examined company.
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