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

Sustainable Development Goals

https://pure.hw.ac.uk/ws/files/10766137/Melchels2010_Biomaterials_31_24_6121.pdf

A review on stereolithography and its applications in biomedical engineering

https://findresearcher.sdu.dk:8443/ws/files/116118561/reverse_logistics.pdf

Reverse logistics and closed-loop supply chain: A comprehensive review to explore the future

Additive manufacturing (AM) technologies have been successfully applied in various applications. Fused deposition modeling (FDM), one of the most popular AM techniques, is the most widely used method for fabricating thermoplastic parts those are mainly used as rapid prototypes for functional testing with advantages of low cost, minimal wastage, and ease of material change. Due to the intrinsically limited mechanical properties of pure thermoplastic materials, there is a critical need to improve mechanical properties for FDM-fabricated pure thermoplastic parts. One of the possible methods is adding reinforced materials (such as carbon fibers) into plastic materials to form thermoplastic matrix carbon fiber reinforced plastic (CFRP) composites those could be directly used in the actual application areas, such as aerospace, automotive, and wind energy. This paper is going to present FDM of thermoplastic matrix CFRP composites and test if adding carbon fiber (different content and length) can improve the mechanical properties of FDM-fabricated parts. The CFRP feedstock filaments were fabricated from plastic pellets and carbon fiber powders for FDM process. After FDM fabrication, effects on the tensile properties (including tensile strength, Young's modulus, toughness, yield strength, and ductility) and flexural properties (including flexural stress, flexural modulus, flexural toughness, and flexural yield strength) of specimens were experimentally investigated. In order to explore the parts fracture reasons during tensile and flexural tests, fracture interface of CFRP composite specimens after tensile testing and flexural testing was observed and analyzed using SEM micrograph.

Additive manufacturing of carbon fiber reinforced thermoplastic composites using fused deposition modeling

An investigation into how the advent of Rapid Manufacturing will influence an individual designer's approach to product design and materials selection is detailed. The assumption is made that Rapid Prototyping machines have evolved into viable manufacturing systems and all associated problems with accuracy, surface finish and repeatability have been resolved. Without the restriction of removing a product from a tool, designers will be free to design any complexity of geometry that they either desire or require. This tool-less approach to manufacturing will have profound implications on the way designers are accustomed to working and will eliminate most Design for Manufacture considerations. Design investigations are presented to highlight the potential importance and scope of Rapid Manufacturing. With advances in a new range of materials, some Rapid Manufacturing is happening today—albeit with existing Rapid Prototyping equipment. However, to enable designers to use existing Rapid Prototyping equipment fo...

Material and design considerations for rapid manufacturing

Sustainable development was articulated by the Brundtland Commission as development that “meets the needs of the present without compromising the ability of future generations to meet their own needs”. Consumers and legislation have pushed companies to re-design their logistics networks in order to mitigate negative environmental and social impacts. The objective of this paper is to design a sustainable recovery network, in which economical, environmental and social impacts are balanced. Life cycle analysis (LCA) has been applied to investigate the environmental impact of different end-of-life (EOL) options. Analytical hierarchy process (AHP) has been utilized to calculate social impacts. Next in this research, a three-objective mathematical programming model has been developed to maximize economic and social benefits and minimize negative environmental impacts, simultaneously. Scrap tires have been considered for a case study. Multi-objective genetic algorithm (MOGA) has been applied to find the Pareto-optimal solutions. In the recovery network of scrap tires, each solution corresponds to a different configuration of the network, based on technology type and location of installed recycling plants. These Pareto-optimal solutions will give some trade off information about the three mentioned objectives, so decision makers can assess the economical impact of efforts of improving the social and environmental issues.

/pdf/designing-sustainable-recovery-network-of-end-of-life-43l36m3x8p.pdf

Designing sustainable recovery network of end-of-life products using genetic algorithm

Purpose
Sustainability of a material-based product mainly depends on the materials used for the product itself or during its lifetime. A material selection decision should not only capture the functional performance required but should also consider the economical, social, and environmental impacts originated during the product life cycle. There is a need to assess social impacts of materials along the full life cycle, not only to be able to address the “social dimension” in sustainable material selection but also for potentially improving the circumstances of affected stakeholders. This paper presents the method and a case study of social life cycle assessment (S-LCA) specialized for comparative studies. Although the authors’ focus is on material selection, the proposed methodology can be used for comparative assessment of products in general.

Social life cycle assessment for material selection: a case study of building materials

This paper studies a flexible job shop problem considering dynamic events such as stochastic job arrivals, uncertain processing times, and unexpected machine breakdowns. Also, the considered job shop problem has routing flexibility and process flexibility. A multi-agent scheduling system has been developed for solution with good quality and robustness. A pheromone-based approach is proposed for coordination among agents. The proposed multi-agent approach is compared with five dispatching rules from literature via simulation experiments to statistical analysis. The simulation experiments are performed under various experimental settings such as shop utilization level, due date tightness, breakdown level, and mean time to repair. The results show that the proposed agent-based approach performs well under all problem settings.

Dynamic flexible job shop scheduling with alternative process plans: an agent-based approach

The use of Rapid Prototyping (RP) techniques for the production of end-use parts is increasing to a stage where Rapid Manufacturing is being undertaken. This paper documents significant initial investigations into the properties of Accura SI40 and SL7560 resins which represent two state of the art stereolithography resins that are aimed at end-use part manufacture. This information has previously been unavailable and is vital for their consideration in end-use part manufacture. The impact of various levels of post curing (ultraviolet and thermal) on the tensile, flexural and impact properties are investigated and correlated with differential scanning calorimetry (DSC) analysis. The isotropy/anisotropy nature of the two materials and also the effect of the notch creation method on the impact resistance were also studied.

/pdf/materials-analysis-of-stereolithography-resins-for-use-in-12z7o21x7w.pdf

Saeed Mansour

Papers

Material and design considerations for rapid manufacturing

Designing sustainable recovery network of end-of-life products using genetic algorithm

Social life cycle assessment for material selection: a case study of building materials

Dynamic flexible job shop scheduling with alternative process plans: an agent-based approach

Materials analysis of stereolithography resins for use in Rapid Manufacturing