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Figures, tables and captions from Chapter 3: Drivers of biodiversity change affecting biological invasions. In: Thematic Assessment Report on Invasive Alien Species and their Control of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services.

Cold spray offers unique possibilities in processing intermetallic-forming or phase-segregating metallic alloys, which are difficult to address by classical melt-metallurgical processes such as casting or thermal spraying due to the formation of large brittle regions or low melting point and volatile eutectics. An example is the production of thick coatings of the copper-indium-gallium (CIG) system on plates or tubes, as they are required in the fabrication of the CIGS(Se) absorber layer of thin film photovoltaic solar modules on an industrial-scale. At the relevant compositions, extended solidification intervals, such as in casting, create material segregation into large brittle CuGa2-type regions intermixed in an indium-rich matrix rendering the cast non-uniform and fragile with high internal stresses. Shrinkage effect further promote porosity. The equilibrium phase diagrams even allow the retention of pure Ga and the In-Ga eutectic, essentially liquid materials at room temperature and highly undesirable for the application. On the other hand, using rapid solidification by gas atomizing the Cu-In-Ga to produce cold spray powder promotes a fine-scaled and uniform phase distribution and microstructure of Cu(In,Ga), CuIn and In. By decoupling the material synthesis from the forming process, this phase distribution can be fully preserved in the cold spray deposition process to advantageously fabricate the coatings for that application. International Thermal Spray Conference 2021, May 24-28, 2021, Virtual Event

In this talk, we present a new methodology for computing projections in tomographic additive manufacturing. Currently, tomographic printing systems require that light-rays in the printing volume are parallel, and have low etendue. In this work, we show that accurate modeling of the light rays through the print volume enables improved printing in systems with diverging beams. We also demonstrate that ray-tracing can compensate for non-parallel projection in 3D. We anticipate that our ray-tracing methodology will relax the hardware requirements necessary in the conventional Radon-based approach, and enable a broader range of tomographic printing configurations. SPIE OPTO 2023 - Emerging Digital Micromirror Device Based Systems and Applications XV, January 28- February 3, 2023, San Francisco, California, United States Series: Proceedings of SPIE

Aeromagnetic data is one of the most widely collected types of data in exploration geophysics. With the continuing prevalence of unmanned air vehicles (UAVs) in everyday life there is a strong push for aeromagnetic data collection using UAVs. However, apart from the many political and legal barriers to overcome in the development of UAVs as aeromagnetic data collection platforms, there are also significant scientific hurdles, primary of which is magnetic compensation. This is a well-established process in manned aircraft achieved through a combination of platform magnetic de-noising and compensation routines. However, not all of this protocol can be directly applied to UAVs due to fundamental differences in the platforms, most notably the decrease in scale causing magnetometers to be significantly closer to the avionics. As such, the methodology must be suitably adjusted. The National Research Council of Canada has collaborated with Aeromagnetic Solutions Incorporated to develop a standardized approach to de-noising and compensating UAVs, which is accomplished through a series of static and dynamic experiments. On the ground, small static tests are conducted on individual components to determine their magnetization. If they are highly magnetic, they are removed, demagnetized, or characterized such that they can be accounted for in the compensation. Dynamic tests can include measuring specific components as they are powered on and off to assess their potential effect on airborne data. The UAV is then flown, and a modified compensation routine is applied. These modifications include utilizing onboard autopilot current sensors as additional terms in the compensation algorithm. This process has been applied with success to fixed-wing and rotary-wing platforms, with both a standard manned-aircraft magnetometer, as well as a new atomic magnetometer, much smaller in scale. American Geophysical Union, Fall Meeting 2019, December 9–13, 2019, San Francisco, CA, USA

Presentation on production state of the Ontario Library Research Cloud (OLRC), a service of the Ontario Council of University Libraries (OCUL) with support from Scholars Portal. The talk also covered future use scenarios and projected subscription costs.

Microscopical Society of Canada 2017 Annual General Meeting, May 9 – 12, 2017, Montreal, Quebec, Canada

INTRODUCTION: Whole-body vibration during helicopter flight can result in adverse health effects, such as neck strain, which can impact performance and safety. The current ISO-2631 whole-body vibration standard does not account for vibration effects on the head and neck. Furthermore, it is unclear as to the extent to which vibration mitigating countermeasures, such as seat cushions, affect vibration transmission to the pilot and reduce head movement and neck strain. This study examined the impact of vibration level and a mitigating cushion on pilot neck strain and head movement. METHODS: Using a human rated shaker facility, the physiological responses of 12 pilots were examined during 15-minute exposures to three levels of vibration (Low=0.23, Normal=0.30, High=0.36 grms) which are representative of forward flight in NRC’s Bell 412 and CF Griffon helicopters. Responses were also compared using either a standard original equipment manufacturer (OEM) or vibration mitigating (MIT) cushion at each vibration level. Electromyography (EMG), as an indicator of neck strain, and seat and head acceleration were recorded continuously. RESULTS: Normalized EMG amplitude was significantly higher during High (OEM= 0.201±1.023, MIT= - 0.008±0.983) compared to Low (OEM = -0.197±0.859, MIT= -0.193±0.991) vibration for both cushions, and amplitude was also higher during Normal (OEM= 0.245±0.914, MIT= -0.048±0.947) compared to Low vibration for the OEM cushion. During Normal and High, the EMG amplitudes were significantly lower, and median frequency significantly higher, with the MIT compared to OEM cushion. Head acceleration was significantly lower with the MIT (1.187±0.261 m∙s⁻ ²) compared to the OEM (1.108±0.234 m∙s⁻ ²) cushion. DISCUSSION: The EMG changes occurring with increased vibration may be indicative of higher neck strain, highlighting the deficiency in ISO-2631 which suggested that the tested vibration levels and durations were within accepted exposure limits. The vibration mitigating cushion was effective in reducing such effects, as well as reducing head acceleration 54th Annual SAFE Symposium, Oct. 31st-Nov. 2nd, 2016, Dayton, Ohio

Social Sciences and Humanities Research Council of Canada; McMaster University; John Douglas Taylor Fund; Department of English and Cultural Studies

IMC 2018, 19th International Microscopy Congress, September 9 – 14, 2018, Sydney, Australia Electronic poster. ID #101