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Defence Research and Development Canada, also DRDC , is an agency of the Department of National Defence , whose purpose is to provide the Canadian Armed Forces , other government departments, and public safety and national security communities with the knowledge and technology needed to defend and protect Canada’s interests at home and abroad.DRDC has approximately 1,400 employees across eight research centres within Canada. Wikipedia.

Osczevski R.,Defence Research and Development Canada
Bulletin of the American Meteorological Society | Year: 2014

The groundbreaking book The Case for Mars (Zubrin 1996) advocates human exploration and colonization of the red planet. One of its themes is that Mars is beset by dragons of the sort that ancient mapmakers used to draw on maps in unexplored areas. The dragons of Mars are daunting logistical and safety challenges that deter human exploration. One such dragon must surely be its weather, for Mars sounds far too cold for human life. Air temperature alone is often a poor indicator of how cold the weather might feel. Wind, for example, makes a big difference to the thermal sensation at any temperature. The mathematical model used for this calculation was developed in 2001 to calculate the values in the wind chill equivalent temperature (WCET) chart for North America. In terms of heat loss rate, surface temperature, and cold sensation, EET is identical to the familiar WCET that is reported each winter across much of North America. It therefore provides a familiar context for assessing the rigors of weather on another planet, in this case Mars.

Hu A.,Defence Research and Development Canada
Journal of physics. Condensed matter : an Institute of Physics journal | Year: 2011

High pressure ab initio evolutionary structure searches resulted in a hydronitrogen solid with a composition of (NH)(4). The structure searches also provided two molecular isomers, ammonium azide (AA) and trans-tetrazene (TTZ) which were previously discovered experimentally and can be taken as molecular precursors for high pressure synthesis of the hydronitrogen solid. The computed pressure versus enthalpy diagram showed that the transformation pressure to the hydronitrogen solid is 36 GPa from AA and 75 GPa from TTZ. Its metastability was analyzed by the phonon dispersion spectrum and room-temperature vibrational density of state together with the transformation energy barrier back to molecular phases at 298 K. The predicted energy barrier of 0.21 eV/atom means that the proposed hydronitrogen solid should be very stable at ambient conditions.

Treurniet J.,Defence Research and Development Canada
ACM Computing Surveys | Year: 2014

A mobility model is used to generate the trajectories of mobile nodes in simulations when developing new algorithms for mobile networks. A model must realistically reflect the scenario in which the technology will be used to reliably validate the algorithm. Considerable progress has been made toward realistic mobility models in the academic literature, and models have become quite complex. A consistent taxonomy has not yet been established for this field. A new multifaceted taxonomy is presented in this work that provides a framework for authors to clearly and consistently describe their models, making them easier to understand and reproduce. By surveying the application field of mobile communication networks, a common nomenclature and a high-level view of existing literature are provided, which are required to reduce duplication of effort and to enable a better sense of the way forward. A tactical scenario demonstrates the application of the taxonomy to model construction. © 2014 ACM.

Peng H.T.,Defence Research and Development Canada
Journal of Biomedical Materials Research - Part B Applied Biomaterials | Year: 2010

Thromboelastography (TEG) is drawing more attention for clinical and in vitro studies of blood coagulation. It can be applied to evaluate the effects of both blood-soluble and insoluble biomaterials on whole blood coagulation from the beginning of coagulation through clot formation to the ending with fibrinolysis. TEG may also identify the relative contributions of various clotting factors, such as fibrinogen and platelets, to the overall coagulation process based on profiles of its variables using whole and partial blood components. A comprehensive review has been conducted on its applications for the assessment of a wide range of blood-contacting biomaterials ranging from polymers to ceramics and biomedical devices involved in many applications. The methodology is different in terms of instrumentation, the methods to activate blood coagulation, the type of blood (citrated versus fresh blood), and study settings (in vitro, in vivo, and clinical trials). The author's own work and future directions are discussed as well. TEG should be considered as one of the most useful tools for evaluating in vitro and in vivo blood-biomaterial interactions for different applications. © 2010 Wiley Periodicals, Inc.

Gierull C.H.,Defence Research and Development Canada
IEEE Transactions on Geoscience and Remote Sensing | Year: 2011

This paper presents the theoretical and experimental performance evaluation of a novel and innovative concept to add a multichannel ground moving target indication (GMTI) capability to a synthetic aperture radar (SAR) reflector antenna with a standard single feed. This approach exploits the capability to achieve a phase center displacement by combining signals obtained from different electromagnetic excitation modes of the feedhorn. While, in the past, this so-called multimode concept has been mainly analyzed in simulation and by various antenna laboratory measurements, several flight experiments have been recently conducted to verify and demonstrate its GMTI performance. The theoretical and experimental analysis provides qualitative and quantitative insights into the effectiveness of multimode SAR-GMTI applications, such as the SAR image-based along-track interferometry (ATI) or post-Doppler GMTI approaches based on space-time adaptive processing. In addition, it introduces practical lessons learned, along with an example of the detection and parameter estimation for a large vessel using ATI. This paper finishes with an examination of the expected performance improvement when the transmitted modes are alternated between subsequent pulses. This toggling results in a time-multiplexed three-channel GMTI system with significantly enhanced estimation performance. © 2011 IEEE.

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