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[SDE]Environmental Sciences and [CHIM.POLY]Chemical Sciences/Polymers

International audience; Although additive layer manufacturing is well established for rapid prototyping the low throughput and historic costs have prevented mass-scale adoption. The recent development of the RepRap, an open source self-replicating rapid prototyper, has made low-cost 3-D printers readily available to the public at reasonable prices (<$1,000). The RepRap (Prusa Mendell variant) currently prints 3-D objects in a 200x200x140 square millimeters build envelope from acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA). ABS and PLA are both thermoplastics that can be injection-molded, each with their own benefits, as ABS is rigid and durable, while PLA is plant-based and can be recycled and composted. The melting temperature of ABS and PLA enable use in low-cost 3-D printers, as these temperature are low enough to use in melt extrusion in the home, while high enough for prints to retain their shape at average use temperatures. Using 3-D printers to manufacture provides the ability to both change the fill composition by printing voids and fabricate shapes that are impossible to make using tradition methods like injection molding. This allows more complicated shapes to be created while using less material, which could reduce environmental impact. As the open source 3-D printers continue to evolve and improve in both cost and performance, the potential for economically-viable distributed manufacturing of products increases. Thus, products and components could be customized and printed on-site by individual consumers as needed, reversing the historical trend towards centrally mass-manufactured and shipped products. Distributed manufacturing reduces embodied transportation energy from the distribution of conventional centralized manufacturing, but questions remain concerning the potential for increases in the overall embodied energy of the manufacturing due to reduction in scale. In order to quantify the environmental impact of distributed manufacturing using 3-D printers, a life cycle analysis was performed on a plastic juicer. The energy consumed and emissions produced from conventional large-scale production overseas are compared to experimental measurements on a RepRap producing identical products with ABS and PLA. The results of this LCA are discussed in relation to the environmental impact of distributed manufacturing with 3-D printers and polymer selection for 3-D printing to reduce this impact. The results of this study show that distributed manufacturing uses less energy than conventional manufacturing due to the RepRap's unique ability to reduce fill composition. Distributed manufacturing also has less emissions than conventional manufacturing when using PLA and when using ABS with solar photovoltaic power. The results of this study indicate that open-source additive layer distributed manufacturing is both technically viable and beneficial from an ecological perspective.

[SDE]Environmental Sciences and [CHIM.POLY]Chemical Sciences/Polymers

International audience; Although additive layer manufacturing is well established for rapid prototyping the low throughput and historic costs have prevented mass-scale adoption. The recent development of the RepRap, an open source self-replicating rapid prototyper, has made low-cost 3-D printers readily available to the public at reasonable prices (<$1,000). The RepRap (Prusa Mendell variant) currently prints 3-D objects in a 200x200x140 square millimeters build envelope from acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA). ABS and PLA are both thermoplastics that can be injection-molded, each with their own benefits, as ABS is rigid and durable, while PLA is plant-based and can be recycled and composted. The melting temperature of ABS and PLA enable use in low-cost 3-D printers, as these temperature are low enough to use in melt extrusion in the home, while high enough for prints to retain their shape at average use temperatures. Using 3-D printers to manufacture provides the ability to both change the fill composition by printing voids and fabricate shapes that are impossible to make using tradition methods like injection molding. This allows more complicated shapes to be created while using less material, which could reduce environmental impact. As the open source 3-D printers continue to evolve and improve in both cost and performance, the potential for economically-viable distributed manufacturing of products increases. Thus, products and components could be customized and printed on-site by individual consumers as needed, reversing the historical trend towards centrally mass-manufactured and shipped products. Distributed manufacturing reduces embodied transportation energy from the distribution of conventional centralized manufacturing, but questions remain concerning the potential for increases in the overall embodied energy of the manufacturing due to reduction in scale. In order to quantify the environmental impact of distributed manufacturing using 3-D printers, a life cycle analysis was performed on a plastic juicer. The energy consumed and emissions produced from conventional large-scale production overseas are compared to experimental measurements on a RepRap producing identical products with ABS and PLA. The results of this LCA are discussed in relation to the environmental impact of distributed manufacturing with 3-D printers and polymer selection for 3-D printing to reduce this impact. The results of this study show that distributed manufacturing uses less energy than conventional manufacturing due to the RepRap's unique ability to reduce fill composition. Distributed manufacturing also has less emissions than conventional manufacturing when using PLA and when using ABS with solar photovoltaic power. The results of this study indicate that open-source additive layer distributed manufacturing is both technically viable and beneficial from an ecological perspective.

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UbiWorld is a concept being developed by the Futures Laboratory group at Argonne National Laboratory that ties together the notion of ubiquitous computing (Ubicomp) with that of using virtual reality for rapid prototyping. The goal is to develop an environment where one can explore Ubicomp-type concepts without having to build real Ubicomp hardware. The basic notion is to extend object models in a virtual world by using distributed wide area heterogeneous computing technology to provide complex networking and processing capabilities to virtual reality objects.

Behavioral Objectives, Change Agents, Educational Innovation, Group Dynamics, Instructional Design, Instructional Materials, Program Development, Program Evaluation, Summative Evaluation, Systems Approach, and Teacher Administrator Relationship

Instructional product development--the purpose of which has been to create materials which produce in an identified population of users demonstrable changes in behavior, in accordance with prespecified and specific objectives--generally adheres to a pattern which includes planning, formulating, prototyping measures and materials, field testing, revising and retesting, and summative evaluation. To the project staff at the Institute for Development of Educational Activities, Inc. (IDEA), this cycle seemed worthwhile to explore in terms of producing materials which would enable groups to improve interpersonal problem-solving skills. Thus, IDEA developed materials designed to help teachers and principal work together more collaboratively and systematically in solving school problems. Field tests of the materials indicated the need for revisions, and evaluations of the program are currently formative. However, the use of product development strategies for organizational development has proven to be of value in serving as a research tool, in forcing clarification of desired outcomes and principles used to attain them, and in expanding our knowledge base with its empirical approach. (SH)

Management, Patrol Frigate, Prototyping, and Combat system land based test site

Ship acquisition is an extremely complex process involving many highly interrelated individual operations, each critical to the completion of the final product. A central issue is the design, test, and evaluation of ship combat systems. This thesis traces the evolution of modern shipboard combat systems and describes current combat system test and evaluation concepts. The utility of prototyping combat systems at land-based test sites is investigated. Ongoing efforts by the Patrol Frigate Acquisition Project to employ a combat system land-based test site in the execution of test and evaluation within present guidelines is described and analyzed. The conclusion is that the plan for utilizing a combat system by the Patrol Frigate program is one viable approach for resolution of uncertainty in ship acquisition. http://archive.org/details/patrolfrigatecom00fees Approved for public release; distribution is unlimited Lieutenant Commander, United States Navy