John Bradford

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[1] Permafrost is a defining characteristic of the Arctic environment. However, climate warming is thawing permafrost in many areas leading to failures in soil structure called thermokarst. An extensive survey of a 600 km area in and around the Toolik Lake Natural Research Area (TLNRA) revealed at least 34 thermokarst features, two thirds of which were new(More)
Large quantities of non-aqueous phase liquids (NAPL), contaminate the near surface sediments at Operable Unit 1 (OU1), Hill Air Force Base (HAFB), Utah. In October 2000, a 3D, multi-offset GPR survey was acquired at OU1 with two objectives: 1) to image the aquifer/aquitard boundary at a depth of about 30 ft, and 2) to evaluate quantitative processing and(More)
SMEs often have to adapt their manufacturing systems to changing circumstances such as technology advances and business growth. This paper presents a new methodology for the redesign of manufacturing systems within SMEs. This paper will show that most approaches to manufacturing systems redesign are linear and it will explain why this is not the best option(More)
The Rocket Engine Design Tool for Optimal Performance-2 (REDTOP-2) is a newly created engineering design tool for use in the conceptual and preliminary design of space transportation systems utilizing liquid propulsion rocket engines. REDTOP-2, one of many unique engineering tools commercially available from SpaceWorks Engineering, Inc. (SEI), represents a(More)
A collaborative design process utilizing Probabilistic Data Assessment (PDA) is showcased. Given the limitation of financial resources by both the government and industry, strategic decision makers need more than just traditional point designs, they need to be aware of the likelihood of these future designs to meet their objectives. This uncertainty, an(More)
The ABLV-GT is a conceptual design for an advanced reusable launch vehicle based on the current NASA Langley ABLV concept. It is a Vision Vehicle class, horizontal takeoff, horizontal landing singlestage-to-orbit vehicle. Main propulsion is provided by Aerojet’s ‘Strutjet’ LOX/LH2 rocket-based combined cycle engine design. The ABLV-GT is designed to deliver(More)
A new 3rd generation, two-stage-to-orbit (TSTO) reusable launch vehicle (RLV) has been designed. The Xcalibur concept represents a novel approach due to its integration method for the upperstage element of the system. The vertical-takeoff booster, which is powered by rocket-based combined-cycle (RBCC) engines, carries the upperstage internally in the aft(More)
High-permittivity layers, related to high-porosity layers or impermeable clay lenses, can act as low-velocity electromagnetic waveguides. Electromagnetic wave phenomena associated with these features are complicated, not well known and not easy to interpret in borehole GPR data. Recently, a novel amplitude analysis approach was developed that is able to(More)