150 research outputs found
Workshop on the EHCR
No full textThis deliverable provides a summary report of a workshop on Electronic Health
Records that was organised and delivered as the main focus of Workpackage 16 of
the Semantic Mining project.
The workshop was held as day three of a three-day series of events held in Brussels
in late November 2004, under the umbrella and with kind support of the
EUROREC organisation.
This report provides a brief summary of that event, and includes in Annex 1 the
complete delegate pack as printed and issued to all persons attending the event,
This delegate pack included printed copies of all slides and screenshots used
throughout the day.
The workshop was well attended, and in particular the organisers are pleased to
report that some very productive discussions took place that will act as the stimulus
for new threads of research collaboration between various Semantic Mining
partners, under the work plan of Workpackage 26.
The organisers are grateful for the support of the EUROREC organisation in
facilitating the organisation of this workshop and for lending their support to it
through their web site and a personal endorsement of the event
Thermo-mechanical fatigue lifetime assessment of spheroidal cast I\iron at different thermal constraint levels
No full textIn previous work on the thermo-mechanical fatigue (TMF) of compacted graphite iron (CGI), lifetimes measured under total constraint were confirmed analytically by numerical integration of Paris’ crack-growth law. In current work, the results for CGI are further validated for spheroidal cast iron (SGI), while TMF tests at different constraint levels were additionally performed. The Paris crack-growth law is found to require a different CParis parameter value per distinct constraint level, indicating that Paris’ law does not capture all physical backgrounds of TMF crack growth, such as the effect of constraint level. An adapted version of Paris’ law is developed, designated as the local strain model. The new model considers cyclic plastic strains at the crack tip to control crack growth and is found to predict TMF lifetimes of SGI very well for all constraint levels with a single set of parameters. This includes not only full constraint but also over and partial constraint conditions, as encountered in diesel engine service conditions. The local strain model considers the crack tip to experience a distinct sharpening and blunting stage during each TMF cycle, with separate contributions to crack-tip plasticity, originating from cyclic bulk stresses in the sharpening stage and cyclic plastic bulk strains in the blunting stage.Emerging Materials(OLD) MSE-3(OLD) MSE-
Use of barbed threads in facial rejuvenation
No full textUse of barbed threads, available with uni- and bi-directional cogs or barbs, is a semi-invasive method of lifting sagging skin of the face. Areas treated with this method include the eyebrows, the cheeks, the jowls and the neck. Ease of use and a shorter down-time have made their use popular. Specific indications, operative procedures, risks and complications are described and some clinical results of the author shown
A Comparative Study of Thermo-Mechanical Fatigue Performance of Different Grades of SiMo Nodular Cast Iron
No full textThis thesis is a comparative study of the Thermo-Mechanical Fatigue (TMF) performance of different grades of SiMo nodular cast iron for heavy-duty diesel engine exhaust gas manifold applications. The TMF performance of the current SiMo variant used to manufacture exhaust manifolds - SiMo 5.10 (C-3.25Si-4.45Mo-0.76), is compared with that of the variants SiMo 4.05 (C-3.22Si-4.66Mo-0.56) and SiMoNi (C-3.3Si-4.5Mo-1Ni-1.3) by performing three out-of-phase (OP) TMF test series under partial constraint conditions. A benchmark TMF test series in the temperature range: 50 ˚C to 550 ˚C with a hold time of 30 s at 550 ˚C showed that SiMo 5.10 had relatively better performance due to development of lower mechanical crack driving forces compared to other variants. However, a long holding time of 600 s at 550 ˚C saw a larger decrease of average TMF lifetimes for SiMo 5.10 than that of SiMo 4.05 despite similar crack driving forces. An investigation of the stress relaxation during TMF of the two variants showed that the SiMo 4.05 performs better during long hold time due to better stress relaxation properties. The SiMoNi variant which is very brittle at low temperatures was found to fail by a fracture by overloading mechanism taking over quite early in the fatigue cycle; which is confirmed by examination of the fracture surfaces and numerical estimations. This also explained the low lifetimes and scatter in previously performed TMF tests under total constraint conditions. The TMF test series performed in the temperature range: 150 ˚C to 550 ˚C with a hold time of 30 s at 550 ˚C found that a heat-treatment seemed to reduce the TMF performance of the SiMo 5.10 variant. Metallographic investigations and hardness measurements of as-cast and heat-treated materials revealed that the distribution of the Mo-rich phase from the grain boundary regions into the matrix due to an annealing heat-treatment seemed to affect the TMF performance.Materials Science and Engineerin
The IDEAlogue 2013: Scholarly Activity Newsletter
No full textHighlights the scholarly activities of Langara faculty members in the 2012-2013 school year. Features successful funding requests, ethical research practices, the research interests of Dr. Jessica Kalra, and information about application for Tri-Council (NSERC, SSHRC, and CIHR) grant funding
Thermo-mechanical fatigue lifetime assessment of spheroidal cast iron at different thermal constraint levels
No full textIn previous work on the thermo-mechanical fatigue (TMF) of compacted graphite iron (CGI), lifetimes measured under total constraint were confirmed analytically by numerical integration of Paris' crack-growth law. In current work, the results for CGI are further validated for spheroidal cast iron (SGI), while TMF tests at different constraint levels were additionally performed. The Paris crack-growth law is found to require a different C-Paris parameter value per distinct constraint level, indicating that Paris' law does not capture all physical backgrounds of TMF crack growth, such as the effect of constraint level. An adapted version of Paris' law is developed, designated as the local strain model. The new model considers cyclic plastic strains at the crack tip to control crack growth and is found to predict TMF lifetimes of SGI very well for all constraint levels with a single set of parameters. This includes not only full constraint but also over and partial constraint conditions, as encountered in diesel engine service conditions. The local strain model considers the crack tip to experience a distinct sharpening and blunting stage during each TMF cycle, with separate contributions to crack-tip plasticity, originating from cyclic bulk stresses in the sharpening stage and cyclic plastic bulk strains in the blunting stage
Weibull analysis of the effect of modified aging treatments on fatigue life of cast aluminium alloy 354
No full textCast aluminium alloy 354 has extensive applications in the automobile industry. Due to its attractive combination of mechanical properties and excellent castability, it is being used in production of automobile components like the compressor wheel for turbochargers. Performance of this component under fatigue loading conditions is a critical issue. The present study explores the possibility of improving the fatigue life of the component by bringing in process changes - (i) adopting a two-step aging treatment in place of the normally used single step aging treatment (ii) adopting a lower artificial aging temperature (171°C) instead of the temperature normally used for artificial aging(188°C) while performing T61 treatment. In all cases Weibull analysis of fatigue test results was carried out. Weibull analysis of Ultimate Tensile Strength (UTS) values obtained after artificial aging at 171°C and 188°C was also carried out. Among the four variants of two-step aging treatment carried out, the one consisting of 100°C for 5 hours followed by 170°C for 5 hours was found to have the best characteristic fatigue life for the components. The modified T61 treatment where aging was carried out at 171°C instead of the normally used 188°C yielded better characteristic fatigue life as well as better Ultimate Tensile Strength (UTS). </p
Weibull analysis of the effect of interrupted aging treatments on the fatigue life of components made of cast Aluminium alloy 354
No full textCast aluminum alloy 354 is widely used in the automobile industry due to its attractive set of mechanical properties and excellent castability. The compressor wheel in turbochargers, for example, is used for the production of this alloy. Apart from mechanical properties like fracture toughness and tensile strength, the fatigue life of the component is also a critical issue while considering the performance. This study makes an attempt to improve the fatigue life of a component made out of this alloy by subjecting it to interrupted aging cycles similar to T6I4 and T6I6 (discussed in the published literature) instead of the normally used T61 standard aging treatment. Results show that subjecting the material to these interrupted aging treatments gives lower fatigue life than that obtained after subjecting it to standard T61 conditions.Also, T6I4 treatment yields better fatigue life as compared to T6I6. </p
Development of a submerged aquatic vegetation growth model in the coupled ocean-atmosphere-wave-sediment transport (COAWST v3.4) model
No full text© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Kalra, T. S., Ganju, N. K., & Testa, J. M. Development of a submerged aquatic vegetation growth model in the coupled ocean-atmosphere-wave-sediment transport (COAWST v3.4) model. Geoscientific Model Development, 13(11), (2020): 5211-5228, doi:10.5194/gmd-13-5211-2020.The coupled biophysical interactions between submerged aquatic vegetation (SAV), hydrodynamics (currents and waves), sediment dynamics, and nutrient cycling have long been of interest in estuarine environments. Recent observational studies have addressed feedbacks between SAV meadows and their role in modifying current velocity, sedimentation, and nutrient cycling. To represent these dynamic processes in a numerical model, the presence of SAV and its effect on hydrodynamics (currents and waves) and sediment dynamics was incorporated into the open-source Coupled Ocean–Atmosphere–Wave–Sediment Transport (COAWST) model. In this study, we extend the COAWST modeling framework to account for dynamic changes of SAV and associated epiphyte biomass. Modeled SAV biomass is represented as a function of temperature, light, and nutrient availability. The modeled SAV community exchanges nutrients, detritus, dissolved inorganic carbon, and dissolved oxygen with the water-column biogeochemistry model. The dynamic simulation of SAV biomass allows the plants to both respond to and cause changes in the water column and sediment bed properties, hydrodynamics, and sediment transport (i.e., a two-way feedback). We demonstrate the behavior of these modeled processes through application to an idealized domain and then apply the model to a eutrophic harbor where SAV dieback is a result of anthropogenic nitrate loading and eutrophication. These cases demonstrate an advance in the deterministic modeling of coupled biophysical processes and will further our understanding of future ecosystem change.This is University of Maryland Center for Environmental Contribution no. 5909
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