Amy C. Courtney, Lubov P. Andrusiv, and Michael W. Courtney
The ability of armour to minimize blast wave transmission is key in mitigating blast-related injuries. The acoustic impedance model is commonly employed to estimate blast wave transmission of candidate armour materials even though the model assumes semi-infinite material thickness. The applicability of the acoustic impedance model to blast wave transmission through plates has not been experimentally verified. In this study, a 79 mm diameter, oxy-acetylene driven shock tube was used to generate a blast-like wave with a peak pressure of 1173 kPa. The pressure wave transmitted through 6.35 mm thick plates of ten different materials spanning a range of acoustic impedances was measured and compared with predictions of the acoustic impedance model. The magnitude of the peak transmitted blast pressure averaged over five trials for each material was well correlated with both the acoustic impedance of the material (correlation coefficient, r = –0.709) and with the predicted peak transmitted blast pressure (r = 0.844). However, in all cases, the acoustic impedance model predicted significantly lower peak blast pressure transmission than was actually observed, with the peak transmitted pressure varying from 9 to 90 times greater than the prediction of the model, with an average transmission of 41 times the prediction of the model. These results show that even though plate materials with higher acoustic impedance tend to transmit lower peak blast pressure, transmitted pressures are much higher than model predictions, and increasing the acoustic impedance does not ensure a decrease in peak transmitted blast pressure when selecting armour materials.
Jean Dumas and Gaétan Demers
Recent developments in materials have enabled the integration of more specific functionalities into textile fabrics, such as the exchange of information or energy distribution. With the increased use of peripheral electronic devices such as communications and sensors, a soldier requires the distribution of information and power around the body. The use of efficient interconnection technologies, embedded directly in electro-textiles inside a soldier’s uniform, would optimize the use and distribution of available power and information. This could lead to important weight savings but also in increased system availability and reliability. This paper presents the development of new wired interconnection and network topologies that could be applied to a combat uniform design. A description of different conductive textiles is presented as well as textile connectors and network topology that were selected for a prototype demonstrator.
Neville A. Stanton and Katie Mettam
Imaging technology has good potential in both security and defence applications due to its ability to present objects from long ranges in poor visibility. Imaging technology is used across the forces in a range of air, land and sea electro-optical sensor applications. In order to be fully aware of imaging technology capabilities it is necessary to understand how it will be affected by image degradation, which types it may be susceptible to, and how well it can support decision making during image recognition. The decision ladder method has previously been noted for its potential use and application in combat identification activities. Here it is used to integrate the literature and is discussed in relation to the task of image recognition, to demonstrate how the different components of recognition relate to the template and to illustrate how some of the different forms of degradation may impact on the constituent parts of the decision-making process.
Matthew Hause and Lars-Olof Kihlström
IEEE Std 610.12−1990 defines architecture as “the fundamental organization of a system embodied in its components, their relationships to each other, and to the environment, and the principles guiding its design and evolution.” [1] With previous versions of architecture frameworks, this was quite difficult. Modelling this evolution or the temporal aspects in architecture frameworks such NAF (NATO Architecture Framework), MODAF (Ministry of Defence Architecture Framework) or the Department of Defence Architecture Framework (DoDAF), have improved the state of the art. These architecture frameworks are based on the use of a four-dimensional ontology such as IDEAS where the spatio-temporal extent of an element is a crucial concept. This is embodied in DoDAF 2 as well as the re-engineering effort of MODAF (MODEM: which provides an IDEAS foundation basis for MODAF). Time can now be dealt with to a much greater extent than previously. The challenge is to identify areas of architecture where time can be modelled and how to take best advantage of it. The Unified Profile for DoDAF and MODAF (UPDM) delivers an implementation of DoDAF 2.0 and MODAF that provides a clear and concise way of expressing concepts dealing with time without requiring the user to become an expert in the DoDAF 2.0 or MODEM “internal wiring” and detailed ontological concepts. Since MODEM was not available when UPDM 2.0 was finalised, MODEM is a requirement for UPDM 3.0. MODEM has also been accepted as the basis for an upgrade of NAF and will make its appearance as NAF version 4.0. This paper will examine the temporal concepts defined in NAF (MODEM) and DoDAF 2.0 and show how time can be effectively integrated into a model to express essential temporal concepts.
Paul Salmon, University of the Sunshine Coast, Queensland, Australia
