THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

The Design and Analysis of Experiments

Natural fibers are getting attention from researchers and academician to utilize in polymer composites due to their ecofriendly nature and sustainability. The aim of this review article is to provide a comprehensive review of the foremost appropriate as well as widely used natural fiber reinforced polymer composites (NFPCs) and their applications. In addition, it presents summary of various surface treatments applied to natural fibers and their effect on NFPCs properties. The properties of NFPCs vary with fiber type and fiber source as well as fiber structure. The effects of various chemical treatments on the mechanical and thermal properties of natural fibers reinforcements thermosetting and thermoplastics composites were studied. A number of drawbacks of NFPCs like higher water absorption, inferior fire resistance, and lower mechanical properties limited its applications. Impacts of chemical treatment on the water absorption, tribology, viscoelastic behavior, relaxation behavior, energy absorption flames retardancy, and biodegradability properties of NFPCs were also highlighted. The applications of NFPCs in automobile and construction industry and other applications are demonstrated. It concluded that chemical treatment of the natural fiber improved adhesion between the fiber surface and the polymer matrix which ultimately enhanced physicomechanical and thermochemical properties of the NFPCs.

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A Review on Natural Fiber Reinforced Polymer Composite and Its Applications

Failure mode and effects analysis (FMEA) is a risk assessment tool that mitigates potential failures in systems, processes, designs or services and has been used in a wide range of industries. The conventional risk priority number (RPN) method has been criticized to have many deficiencies and various risk priority models have been proposed in the literature to enhance the performance of FMEA. However, there has been no literature review on this topic. In this study, we reviewed 75 FMEA papers published between 1992 and 2012 in the international journals and categorized them according to the approaches used to overcome the limitations of the conventional RPN method. The intention of this review is to address the following three questions: (i) Which shortcomings attract the most attention? (ii) Which approaches are the most popular? (iii) Is there any inadequacy of the approaches? The answers to these questions will give an indication of current trends in research and the best direction for future research in order to further address the known deficiencies associated with the traditional FMEA.

Review: Risk evaluation approaches in failure mode and effects analysis: A literature review

Fibre-reinforced composites are rapidly gaining market share in structural applications, but further growth is limited by their lack of toughness. Fibre hybridisation is a promising strategy to toughen composite materials. By combining two or more fibre types, these hybrid composites offer a better balance in mechanical properties than non-hybrid composites. Predicting their mechanical properties is challenging due to the synergistic effects between both fibres. This review aims to explain basic mechanisms of these hybrid effects and describes the state-of-the-art models to predict them. An overview of the tensile, flexural, impact and fatigue properties of hybrid composites is presented to aid in optimal design of hybrid composites. Finally, some current trends in fibre hybridisation, such as pseudo-ductility, are described.

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Fibre hybridisation in polymer composites: a review

In recent years, nanocomposites based on various nano-scale carbon fillers, such as carbon nanotubes (CNTs), are increasingly being thought of as a realistic alternative to conventional smart materials, largely due to their superior electrical properties. Great interest has been generated in building highly sensitive strain sensors with these new nanocomposites. This article reviews the recent significant developments in the field of highly sensitive strain sensors made from CNT/polymer nanocomposites. We focus on the following two topics: electrical conductivity and piezoresistivity of CNT/polymer nanocomposites, and the relationship between them by considering the internal conductive network formed by CNTs, tunneling effect, aspect ratio and piezoresistivity of CNTs themselves, etc. Many recent experimental, theoretical and numerical studies in this field are described in detail to uncover the working mechanisms of this new type of strain sensors and to demonstrate some possible key factors for improving the sensor sensitivity.

Piezoresistive Strain Sensors Made from Carbon Nanotubes Based Polymer Nanocomposites

A study on the flexural properties of hybrid composites reinforced by S-2 glass and T700S carbon fibres is presented in this paper Specimens were manufactured following the hand lay-up process in an intra-ply configuration with varying degrees of glass fibres added to the surface of a carbon laminate These specimens were then tested in the three point bend configuration in accordance with ASTM D790-07 at a span to depth ratio of 32 The failure modes were examined under an optical microscope, and the results show that the dominant failure mode is compressive failure The flexural modulus, flexural strength and strain to failure were also predicted by finite element analysis It is seen that flexural modulus decreases with increasing percentage of S-2 glass fibres Both the experiments and FEA suggest that positive hybrid effects exist by substituting carbon fibres with glass fibres

Flexural properties of hybrid composites reinforced by S-2 glass and T700S carbon fibres

Optimal design for the flexural behaviour of glass and carbon fibre reinforced polymer hybrid composites

Natural fibre-reinforced hybrid composites which contain one or more types of natural reinforcement are gaining increasing research interest. This paper presents a review of natural fibre-reinforce...

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Review of natural fibre-reinforced hybrid composites:

Natural fibres are cheaper and have a lower density compared to synthetic reinforcement products and therefore offer benefits for use in commercial applications. The physical and mechanical properties of these ‘eco-composites’ can be further enhanced through the addition of nanoclay. This paper reports on the fabrication of vinyl ester, eco-composites and eco-nanocomposites and characterises these samples in terms of water absorption, strength, toughness, and thermal properties. Weight gain and FTIR spectrum analysis indicated that 5% nanoclay addition gave favourable reduction in the water absorption behaviours of the samples. Nanoclay addition strengthened fibre–matrix adhesion leading to improved strength properties in the eco-nanocomposites. However, SEM images of fracture surfaces revealed that nanoclay addition limited toughness mechanisms of fibre pull-out and fibre debonding leading to sample brittleness. Eco-nanocomposites were still found to have favourable thermal stability and flammability results.

Chensong Dong

Papers

Flexural properties of hybrid composites reinforced by S-2 glass and T700S carbon fibres

Optimal design for the flexural behaviour of glass and carbon fibre reinforced polymer hybrid composites

Review of natural fibre-reinforced hybrid composites:

Characterisation of the water absorption, mechanical and thermal properties of recycled cellulose fibre reinforced vinyl-ester eco-nanocomposites

Effects of Process-Induced Voids on the Properties of Fibre Reinforced Composites