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Humberto Hijar‐Rivera and Victor Garcia‐Castellanos
The purpose of this paper is to present computer‐generated combined arrays as efficient alternatives to Taguchi's crossed arrays to solve robust parameter problems.
Abstract
Purpose
The purpose of this paper is to present computer‐generated combined arrays as efficient alternatives to Taguchi's crossed arrays to solve robust parameter problems.
Design/methodology/approach
The alternative combined array designs were developed for the cases including six to twelve variables where CMR designs are not smaller than Taguchi's designs. The efficiency to estimate the effects of interest was calculated and compared to the efficiency of the corresponding CMR designs.
Findings
For all the cases investigated at least one computer generated combined array design was found with the same size as the CMR design and with higher efficiency.
Practical implications
Robust parameter design identifies appropriate levels of controllable variables in a process for the manufacturing of a product. The designed experiments involve the controllable variables along with the uncontrollable or noise variables to design a product or process that will be robust to changes in these noise variables. Response surface methodology estimates the actual relationship between the response and the input variables with an empirical model based on the designed experiment. Once the empirical model is fitted, the surface described by the model can be used to describe the behavior of the response over the experimental region. The higher efficiency of the computer generated combined array designs proposed in this research produces lower variances for the parameter estimates and lower variance of prediction for the model. As a result, the response will be described in a more realistic form.
Originality/value
The paper shows that using a computer‐generated design to solve a robust parameter problem will result in a better approximation to the true response of the process. Consequently, optimizing the fitted model will produce settings for the parameters closer to the real optimal settings.
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This paper uses a historical case study, the controversy over the possibility of climatic extremes caused by hydrogen bomb tests on Pacific Ocean atolls during the 1950s, to show…
Abstract
Purpose
This paper uses a historical case study, the controversy over the possibility of climatic extremes caused by hydrogen bomb tests on Pacific Ocean atolls during the 1950s, to show how, in a context of few scientific data and high uncertainty, political affiliations and public concerns shaped two types of argumentation, the “energy” and the “precautionary” arguments.
Design/methodology/approach
Systematic analysis of publications 1954–1956: scientific and semiscientific articles, publications of C.-N. Martin and contemporary newspaper articles, especially from the Asia–Pacific region.
Findings
First, epistemological and scientific reasoning about the likelihood of extreme natural events aligned to political convictions and pressure. Second, a geographical and social distribution of arguments: the relativizing “energy argument” prevailed in English-language scientific journals, while the “precautionary argument” dominated in popular journals and newspapers published worldwide. Third, while the “energy argument” attained general scientific consensus within two years, it lost out in the long run. The proponents of the “precautionary argument” raised relevant research questions that, though first rejected in the 1950s, later exposed the fallacies of the “energy argument” (shown for the case of the climatologist William W. Kellogg).
Originality/value
In contrast to the existing secondary literature, this paper presents a balanced view of the weaknesses and strengths of two lines of arguments in the 1950s. Further, this historical study sheds light on how once-discarded scientific theories may ultimately be reconsidered in a completely different political and scientific context, thus justifying the original precautionary argument.
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Jorge Alejandro Silva Rodríguez de San Miguel
The purpose of this paper is to analyse the measures taken by the Mexican Government in relation to the country’s climate change and its management to improve it.
Abstract
Purpose
The purpose of this paper is to analyse the measures taken by the Mexican Government in relation to the country’s climate change and its management to improve it.
Design/methodology/approach
Much of the information which has guided this review was sourced from official documents referred to the climate change initiatives in Mexico, especially technical reports and working papers. The selection of literature was considered based on its recency, academic importance and veracity. The studies selected mainly ranged from 2001 to 2017.
Findings
This review finds that further research is required to assess Mexico’s climate change efforts objectively, which will help to ascertain if the nation’s plans and commitment are as ambitious and strong as the country claims.
Research limitations/implications
Most of the literature considered in this review was sourced from official documents and has not been subject to extensive academic peer review to guarantee that national decision and policy making are based on reliable scientific knowledge.
Originality/value
Mexico is one of the first countries to introduce a law dedicated to climate change, and its inclusion of short-term climate pollutants in its National Climate Change Strategy makes it more ambitious than that of many other Latin American countries. However, literature on the subject is limited and fragmented.
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