7 research outputs found

    OPTIMIZATION OF COMPRESSION MOULDING PARAMETERS FOR MULTI FILLER POLYMER COMPOSITE USING TAGUCHI METHOD

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    Polymer Electrolyte Membrane Fuel Cells (PEMFC) performance depends on the properties of bipolar plates (BP). In order to produce the best performance of BP, compression moulding parameters need to be optimized. This study determined the compression moulding parameters of Graphite (G) / Carbon Black (CB) / Carbon Fiber (CF) / Polypropylene (PP) composites using Taguchi method (TM) in order to optimize the properties of BP plate. L9 Orthogonal Array with four factors and three levels was chosen as a design of experiment for G/CB/CF/PP composition with a weight percentage of 50/25/5/20. The factors selected for this study were heating temperature, load, preheating pressing time and pressing time. The electrical conductivity value of each sample was analyzed by signal to noise ratio using TM with the larger-the-better condition in order to determine the optimum parameters. Confirmation experiment was conducted to validate the optimum parameters obtained from the TM. The electrical conductivity result of G/CB/CF/PP composites for confirmation experiment was 393.49 S/cm and it was higher than nine trials and the TM predicted value. Hence, the optimum parameters of compression moulding can be obtained using TM to improve the electrical conductivity of G/CB/CF/PP composites. TM is an effective way to get the optimal moulding parameters for G/CB/CF/PP composites and is very useful to fabricate bipolar plate for PEMFC

    Supporting knowledge transfer in web-based managed IT support

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    Purpose &ndash; The purpose of this paper is to highlight the importance and complexities of the knowledge transfer process in the provision of effective managed after-sales IT support, when the web is used for service delivery.Design/methodology/approach &ndash; The paper features an interpretive case study of a multinational Managed Service Provider (MSP) and a focus group of representatives from five comparable MSPs.Findings &ndash; The paper finds that MSPs that use web-based channels for the provision of after-sales IT support services need to address a range of important social and organisational issues in order to realise cost and efficiency-based benefits.Research limitations/implications &ndash; The paper provides a four stage processual model of knowledge transfer in the provision of web-based managed after-sales IT support services. The barriers and enablers of knowledge transfer at each stage are identified. The paper adopts a MSP perspective and suggests that further research from the customer perspective is required.Practical implications &ndash; The paper highlights some important social and organisational enablers and barriers, which will guide MSPs when providing managed after-sales IT support using webbased channels.Originality/value &ndash; The paper provides the first staged model of inter-organisational knowledge transfer in a complex multi-organisational and multi-channel web-based context.<br /

    Rising rural body-mass index is the main driver of the global obesity epidemic in adults

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    Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities 1,2 . This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity 3�6 . Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55 of the global rise in mean BMI from 1985 to 2017�and more than 80 in some low- and middle-income regions�was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing�and in some countries reversal�of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories. © 2019, The Author(s)

    Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight

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    From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions. © Copyright
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