56,965 research outputs found
Scanlan, P J, 442194
This record was harvested from a previous catalogue system and will be withdrawn in 2025. Information in this record may be superseded or incomplete. Visit this record in UMA's new catalogue at: https://archives.library.unimelb.edu.au/nodes/view/415528Surname: SCANLAN. Given Name(s) or Initials: P J. Military Service Number or Last Known Location: 442194. Missing, Wounded and Prisoner of War Enquiry Card Index Number: SEA-5203.236174
Item: [2016.0049.47789] "Scanlan, P J, 442194
Design and flight test of a civil unmanned aerial vehicle for maritime patrol: the use of 3D-printed structural components
This paper describes the design of the “Spotter” unmanned aerial vehicle, developed by the University of Southampton as part of the 2SEAS-3i European Interreg project. Spotter is a twin engine, 4m wing span, fixed-wing aircraft which has been designed to perform long-endurance, all-weather patrol missions in coastal and maritime environments. Reliability and safety have been among the strongest design drivers of this project; Spotter is able to survive the failure of one engine and of any single control surface. A modular approach has been adopted for the payload unit in order to allow the users to rapidly interchange the sensors required to perform different missions.One of the most innovative aspects of Spotter is the extensive use of the Selective Laser Sintering (SLS) technology (also known as 3D printing) for many of the components of its airframe. By eliminating tooling and manual labour, the 3D printing technology allows the designer to produce complex and high-performance structures at a relatively low cost and within hours of the completion of the design. Spotter and a sub-20kg version, codenamed 2SEAS-20, have undergone an extensive flight test campaign, totalling hundreds of autonomous flights (including autonomous take-off and landings) and many flight hours. This has provided the opportunity to test the reliability and robustness of the system and to gain a deeper insight into the opportunities and problems presented by the use of 3D printed structures for large airframe components
An aerospace component cost modelling study for value driven design
Demand is increasing in aero-engine products for better efficiency and environmental performance whilst keeping the cost low. Unlike performance, the physics behind cost is least understood. This paper presents a proposed unit cost modelling methodology applied to a Rolls-Royce aero-engine fan blade. An objective of the cost model is the allow engineers to understand the breakdown of cost. A value driven design concept is outlined and presents an opportunity to conduct design optimisation
Framework for aircraft cost optimization using multidisciplinary analysis
This report summarizes the work that has been carried out as part of the Flapless Air Vehicle Integrated Industrial Research project, a five-year research program looking at technologies for future aircraft. A novel classification of aircraft product definition is used, and a framework to estimate the life cycle cost of aircraft using the product definition is presented. The acquisition costs are estimated using a hierarchical structure and a discrete-event simulation model is used to estimate the maintenance and operation costs. The cost models developed are integrated into the conceptual aircraft design process to facilitate the comparison between different configurations. The usage of the life cycle cost framework as a decision support tool is outlined by using the cost models to perform multidisciplinary analysis and optimization studies
Measurement of the ratio of prompt χ c to J / ψ production in pp collisions at √s = 7 TeV
The prompt production of charmonium χ c and J / ψ states is studied in proton-proton collisions at a centre-of-mass energy of √s = 7 TeV at the Large Hadron Collider. The χ c and J / ψ mesons are identified through their decays χ c → J / ψ γ and J / ψ → μ + μ - using 36 pb - 1 of data collected by the LHCb detector in 2010. The ratio of the prompt production cross-sections for χ c and J / ψ, σ (χ c → J / ψ γ) / σ (J / ψ), is determined as a function of the J / ψ transverse momentum in the range 2 < p T J / ψ < 15 GeV / c. The results are in excellent agreement with next-to-leading order non-relativistic expectations and show a significant discrepancy compared with the colour singlet model prediction at leading order, especially in the low p T J / ψ region
Invariable biomass-specific primary production of taxonomically discrete picoeukaryote groups across the Atlantic Ocean
Oceanic photosynthetic picoeukaryotes (< 3 µm) are responsible for > 40% of total primary production at low latitudes such as the North-Eastern tropical Atlantic. In the world ocean, warmed by climate changes, the expected gradual shift towards smaller primary producers could render the role of photosynthetic picoeukaryotes even more important than they are today. Little is still known, however, about how the taxonomic composition of this highly diverse group affects primary production at the basin scale. Here, we combined flow cytometric cell sorting, NaH14CO3 radiotracer incubations and class-specific fluorescence in situ hybridization (FISH) probes to determine cell- and biomass-specific inorganic carbon fixation rates and taxonomic composition of two major photosynthetic picoeukaryote groups on a ?7500-km-long latitudinal transect across the Atlantic Ocean (Atlantic Meridional Transect, AMT19). We show that even though larger cells have, on average, cell-specific CO2 uptake rates ?5 times higher than the smaller ones, the average biomass-specific uptake is statistically similar for both groups. On the other hand, even at a high taxonomic level, i.e. class, the contributions to both groups by Prymnesiophyceae, Chrysophyceae and Pelagophyceae are significantly different (P < 0.001 in all cases). We therefore conclude that these group's carbon fixation rates are independent of the taxonomic composition of photosynthetic picoeukaryotes across the Atlantic Ocean. Because the above applies across different oceanic regions the diversity changes seem to be a secondary factor determining primary production
Modeling of modulus graded axisymmetric adhesive joints
This study presents a refined theoretical framework for the stress analysis of modulus graded axisymmetric adhesive joints which takes into account the radial stresses in the bonded assembly. This semi-analytical is based on a variational method which minimizes the complementary energy of the bonded system. The joint consists of similar or dissimilar polar anisotropic composite adherends or metallic adherends and a functionally modulus graded bondline (FMGB) adhesive. The elastic modulus of the adhesive is functionally graded along the bondlength by assuming smooth modulus profiles which reflect the behavior of practically producible graded bondline. The stress distribution predicted by this refined model is compared with that of MMB model which also accounts for in the bonded system to estimate reduction in shear and peel stress peaks in the bondline. The axisymmetric stress analysis reveals that the peel and shear stress peaks in the FMGB are much smaller and the stress distribution is more uniform along its length than those of mono-modulus bondline (MMB) adhesive joints under the same axial tensile load. A systematic parametric study has been conducted by selectively perturbing the material and geometrical properties of the joint in order to study their influence onstress distribution in the bondline. Furthermore, the results suggest that the peel and shear strengths can be optimized by spatially controlling the modulus of theadhesive
A generic operational simulation for early design civil unmanned aerial vehicles
Contemporary aerospace programmes often suffer from large cost overruns, delivery delays and inferior product quality. This is caused in part by poor predictive quality of the early design phase processes with regards to the operational environment of a product. This paper develops the idea of a generic operational simulation that can help designers to rigorously analyse and test their early product concepts. The simulation focusses on civil Unmanned Air Vehicle products and missions to keep the scope of work tractable. The research agenda is introduced along with ideas, initial results and future work. Designers specify details about their product, its environment and anticipated operational procedures. The simulation returns information that can help to estimate the value of the product using the value-driven design approach. Information will include recurring and non-recurring mission cost items. The research aim is to show that an operational simulation can improve early design concepts, thereby reducing delays and cost overruns. Moreover, a trade-off between mission fidelity and model generality is sought along with a generic ontology of civil Unmanned Air Vehicle missions and guidelines about capturing operational informatio
Letter from Carl Hayden to P. J Moran
Letter from Carl T. Hayden to P. J. Moran concerning the alignment of the road to Bright Angel Trail
On axisymmetric adhesive joints with graded interface stiffness
An improved analytical model is presented for the stress analysis of interface stiffness graded axisymmetric adhesive joints. The governing integro-differential equation of the problem is obtained through a variational method which minimizes the complementary energy of the bonded assembly. The joint is composed of similar or dissimilar polar anisotropic and/or isotropic adherends and a functionally modulus graded bondline (FMGB) adhesive. The elastic modulus of the adhesive is functionally graded along the bondlength by assuming smooth modulus profiles which reflect the behavior of practically producible graded bondline. Influence of non-zero radial stresses in the bonded system on shear and normal stresses is evaluated. The stress distribution predicted by this refined model is compared with that of mono-modulus bondline (MMB) model for the same axial tensile load in order to estimate reduction in shear and normal stress peaks in the bondline and the adherends. A systematic parametric study indicates that an optimum joint strength can be achieved by employing a stiffness graded bondline with an appropriate combination of geometrical and material properties of the adherends. This model can also be applied to examine the effects of loss of interface stiffness due to an existing defect and/or damage in the bondlin
- …
