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The efficiency of several Microstrip (Patch) antennas with varying substrate heights etched on a substrate material with a relatively high dielectric constant was calculated from gain measurement data. The radiation efficiency of a 4, 5, 6 and 7mm thick patches were measured to be 0.8887, 0.9097, 0.9163 and 0.9202, respectively. The efficiency of a λ/4 monopole at the same frequency was measured to be 0.9389. To achieve a -2.0 dBi of gain at an elevation angle θ = 90° and a +2 dBic at elevation angles between 30° and 70° for the XM signal reception, the patch efficiency has to exceed the efficiency of a λ/4 monopole at the same frequency.

Life Cycle Assessments (LCA) of complex systems, such as vehicles and vehicle components, are based on the quantification of the energy, wastes, and emissions associated with the material production, manufacturing, use and end of life of the product. However, the volume of information needed to provide a comprehensive assessment of the environmental burdens is large and complicates the decision process in choosing among alternatives. For this reason people have attempted to simplify the information by collapsing it into a single index, which essentially assigns a score to a product of being “good” or “bad”. Even though such an approach looks attractive to the decision-makers that want simple answers based on meaningful data, the results may be misleading.

Saturn Corporation and its suppliers are partnering with the U.S. Environmental Protection Agency (EPA) Design for the Environment (DfE) Program and the University of Tennessee (UT) Center for Clean Products and Clean Technologies (CCPCT) in a project to develop a model for life-cycle management (LCM). This paper presents key findings from the first phase of the project, a survey by Saturn of its suppliers to determine their interests and needs for a supply chain LCM project, and identifies framework strategies for successful LCM.

Free form fabrication, or rapid prototyping as it is commonly known, is the creation of a physical entity, directly from numerical description, using an additive process. The mathematical data used is typically in the form of a 3D CAD file, but it may also be obtained from a reverse engineering process. This paper presents a review of three of the leading FFF (free form fabrication) systems which are commercially available. Time constraints will allow us to describe only three of these products. Although this does not do justice to a technology where there are more than 30 different systems in various stages of development, these examples represent the vast majority of machines which are in the marketplace today.