The effect of operating conditions on post-injection fuel discharge in an optical engine

After the end of injection, the needle closes and residual fuel present inside the injector sac and orifices is discharged due to the high fluid inertia. This so-called post-injection fuel discharge can present several problems. The excess fuel can undergo incomplete combustion due to its large, slow moving and often surface-bound nature. Not only does this have a negative effect on emissions and performance, but it has been speculated that the by-products of incomplete combustion are implicated in the growth of carbonaceous deposits on the tips of fuel injectors. Accumulation of these deposits is known to lead to premature fuel injector failure that can lead to re-ductions in power output and engine lifetime. Seeing as modern multiple-injection strategies give rise to an in-creased number of transient injection phases, post-injection discharges are an increasingly common occurrence during normal operating conditions. In order to develop a phenomenological model for the fluid dynamics after the end of injection, there is a need to characterise the causes of this discharge and how they might be influenced by engine operating conditions. In this study we present ongoing analysis into results from the first visualisation of post injection fuel discharge at the microscopic level under engine-like operating conditions. We observed the process of fuel discharge for multi-hole injectors, using a high-speed camera fitted with a long-distance micro-scope and a high-speed laser illumination source. We related the effect of a variety of operating conditions on the severity of this process, including injection pressure and in-cylinder pressure along with a characterisation of the dynamics of the various modes by which these undesired liquid structures are produced. We present the different modes by which this process occurs and we conclude that the extent of post-injection discharge depends on both the in-cylinder and injection pressures

Safe anytime-valid inference: from theory to implementation in psychiatry research

Classical statistical methods, such as p-values, are difficult for researchers to apply correctly. They for example do not allow drawing conclusions from a study early, or for extending a study with extra research groups that want to make their data available later. Sadly, in practice this often leads to faulty application of statistics and subsequent invalidity of experiment conclusions.Partly because of the above, recently, interest in safe, anytime-valid inference (SAVI) with e-values has emerged. This framework offers the same functionality as classical statistics, but also provides researchers with plenty of flexibility, for example through enabling early stopping and effect estimation at any time, extending a study in hindsight, and analyzing data located across multiple hospitals.  In this thesis, this theory is further developed for performing SAVI in scenarios applicable to healthcare, specifically for several use-cases in psychiatry. It is explored how one could set up real-time psychiatry research in practice in an automated manner, combining text mining with network analysis techniques for data preparation and exploration and then confirming hypotheses with SAVI. Through this, the work in this thesis contributes to an environment where continuous learning from routinely collected healthcare data for better personalized recommendations is the new standard.NWO628.011.028Number theory, Algebra and Geometr

Improved understanding of groundwater flow in complex superficial deposits using three-dimensional geological-framework and groundwater models: an example from Glasgow, Scotland (UK)

Groundwater models are useful in improving knowledge of groundwater flow processes, both for testing existing hypotheses of how specific systems behave and predicting the response to various environmental stresses. The recent advent of highly detailed three-dimensional (3D) geological-framework models provides the most accurate representation of the subsurface. This type of modelling has been used to develop conceptual understanding of groundwater in the complex Quaternary deposits of Glasgow, Scotland (UK). Delineating the 3D geometry of the lithostratigraphical units has allowed the most detailed conceptualisation of the likely groundwater flow regime yet attempted for these superficial deposits. Recharge and groundwater flow models have been developed in order to test this conceptual understanding. Results indicate that the direction of groundwater flow is predominantly convergent through the permeable, relatively thick Quaternary deposits of the Clyde valley towards the River Clyde, which runs through Glasgow, with some indication of down-valley flow. A separate nearby system with thick and potentially permeable Quaternary deposits, the Proto-Kelvin Valley, may also be a significant conveyor of groundwater towards the River Clyde, although the absence of local data makes any conclusions conjectural. To improve the robustness of the current model there is a need for an overall increase in good quality groundwater-level data, particularly outside central Glasgow. A prototype groundwater-monitoring network for part of Glasgow is an encouraging development in this regard. This would allow the development of a time-variant groundwater model which could be used to study future modelling scenarios

Wildlife Harvesting and Sustainable Regional Native Economy in the Hudson and James Bay Lowland, Ontario

To assist the Omushkego Cree in planning a community and regional economic development strategy that takes into account the traditional economy, we developed appropriate methodologies to investigate the quantitative importance and economic value of hunting and fishing for the Mushkegowuk region, Hudson and James Bay Lowland. Harvests of wildlife by the 6500 aboriginal residents of eight communities - Moose Factory, Moosonee, New Post, Fort Albany, Kashechewan, Attawapiskat, Peawanuck and Fort Severn - were estimated by means of a questionnaire study. A total of 925 persons were interviewed for 56% coverage in a stratified sampling design. Four species (moose, Canada goose, caribou, lesser snow goose) accounted for about two-thirds of the 1990 bush food harvest of 687 000 kg, the equivalent of 402 g meat or 97 g protein per adult per day. The replacement value of the bush food harvested in the region was about $7.8 million in 1990. Including other products of the land (fur, fuelwood, berries), the total value of the traditional economy,$9.4 million for the region or $8400 per household per year, was about one-third as large as the total cash economy. The results show that the traditional economy is a cornerstone of the regional mixed economy, and that such a mixed economy may persist as a culturally and environmentally sustainable base for the region.Key words: Hudson Bay and James Bay Lowland, Canadian subarctic, Cree, sustainable development, subsistence, wildlife, fisheriesDans le but d'aider les Cris Omushkego à planifier une stratégie de développement économique communautaire et régional qui tienne compte de l'économie traditionnelle, on a mis au point des méthodologies appropriées permettant d'enquêter sur l'importance quantitative et sur la valeur économique de la chasse et de la pêche pour la région de Mushkegowuk, dans les basses-terres de la baie d'Hudson et de la baie James. Une étude faite à l'aide d'un sondage a permis d'évaluer le nombre de prises d'animaux par les 6500 autochtones habitant les huit communautés de Moose Factory, Moosonee, New Post, Fort Albany, Kashechewan, Attawapiskat, Peawanuck et Fort Severn. Un total de 925 personnes ont été interviewées formant 56 p. cent d'un plan d'échantillonnage stratifié. Quatre espèces (l'orignal, la bernache du Canada, le caribou et la petite oie blanche) comptaient pour environ les deux tiers des prises provenant de la nature au cours de l'année 90. Le poids de ces prises était de 687 000 kg, soit l'équivalent quotidien de 402 g de viande ou de 97 g de protéine par adulte. La valeur de remplacement de la nourriture tirée de la nature dans la région était d'environ 7,8 millions de dollars en 1990. Si l'on inclut les autres produits de la nature (fourrure, bois de feu, baies), la valeur totale de l'économie traditionnelle - 9,4 millions de dollars pour la région ou 8400 dollars annuels par foyer - équivalait à environ un tiers de l'économie monétaire totale. Les résultats montrent que l'économie traditionnelle est un pilier de l'économie mixte régionale et que cette dernière peut persister en tant qu'assise durable sur le plan culturel et environnemental pour la région.Mots clés: basses-terres de la baie d’Hudson et de la baie James, subarctique canadien, Cris, développement durable, subsistance, faune, pêcherie

The Persistence of Aboriginal Land Use: Fish and Wildlife Harvest Areas in the Hudson and James Bay Lowland, Ontario

The question of the extent and importance of contemporary aboriginal land use in the Canadian North remains controversial, despite more than 20 studies undertaken since the mid-1970s to document Native land claims and to assess impacts of development projects. In planning a community and regional development strategy that takes into account traditional land use and economy, methodologies were developed for a computer-based, integrated land use and wildlife harvest study that could be applied over large geographic areas. Wildlife harvesting areas used in 1990 by the aboriginal people of the Mushkegowuk region, Hudson and James Bay Lowland, were documented by interviewing 925 hunters from eight communities (Moose Factory, Moosonee, New Post, Fort Albany, Kashechewan, Attawapiskat, Peawanuck and Fort Severn). Results show that geographically extensive land use for hunting and fishing persists in the Mushkegowuk region, some 250 000 sq km. However, the activity pattern of Omushkego (West Main) Cree harvesters has changed much over the decades; contemporary harvesting involves numerous short trips of a few days' duration instead of the traditional long trips. Although the First Nations control only 900 sq km (0.36% of the region) as Indian reserve land, they continue to use large parts of their traditional territory.Key words: land use, aboriginal territories, Hudson Bay and James Bay Lowland, Canadian subarctic, Cree, subsistence, wildlife, fisheriesLa question du niveau et de l'importance de l'utilisation actuelle des terres aborigènes dans le Nord canadien demeure controversée, malgré plus de 20 études entreprises depuis le milieu des années 70 afin de documenter les revendications territoriales des autochtones et d'évaluer l'impact des projets de développement. Dans le but de planifier une stratégie de développement communautaire et régional qui tienne compte de l'utilisation des terres et de l'économie traditionnelles, on a mis au point des méthodologies pour une étude intégrée de l'utilisation des terres et prélèvement faunique, en se servant d'ordinateurs, méthodologies qui pourraient être appliquées à de vastes régions géographiques. On a documenté les zones de prélèvement faunique utilisées en 1990 par les peuples autochtones de la région de Mushkegowuk, basse-terre de la baie d'Hudson et de la baie James, en interviewant 925 chasseurs de huit communautés (Moose Factory, Moosonee, New Post, Fort Albany, Kashechewan, Attawapiskat, Peawanuck et Fort Severn). Les résultats montrent qu'une utilisation intensive, du point de vue géographique, pour la chasse et la pêche persiste dans la région de Mushkegowuk, soit quelque 250 000 km². Cependant, le type d'activité de prélèvement des Cree Omushkego (West Main) a beaucoup changé au cours des ans; les prélèvements contemporains sont réalisés lors de nombreuses expéditions de quelques jours seulement, plutôt que lors de longues expéditions traditionnelles. Bien que les Premières Nations ne contrôlent que 900 km² (0,36 p. cent de la région) en tant que terres de réserve indienne, elles continuent d'utiliser une grande superficies du territoire traditionnel.Mots clés: utilisation des terres, territoires autochtones, basse-terre de la baie d’Hudson et de la baie James, subarctique canadien, Cree, subsistance, faune, pêcherie

The effect of inspiratory muscle training on respiratory and limb locomotor muscle deoxygenation during exercise with resistive inspiratory loading.

We investigated how inspiratory muscle training impacted respiratory and locomotor muscle deoxygenation during submaximal exercise with resistive inspiratory loading. 16 male cyclists completed 6 weeks of either true (n=8) or sham (n=8) inspiratory muscle training. Pre- and post-training, subjects completed 3, 6-min experimental trials performed at ~80%  ˙VO2peak with interventions of either moderate inspiratory loading, heavy inspiratory loading, or maximal exercise imposed in the final 3 min. Locomotor and respiratory muscle oxy-, deoxy-, and total-haemoglobin and myoglobin concentration was continuously monitored using near-infrared spectroscopy. Locomotor muscle deoxygenation changes from 80%  ˙VO2peak to heavy inspiratory loading were significantly reduced pre- to post-training from 4.3±5.6 µM to 2.7±4.7 µM. Respiratory muscle deoxygenation was also significantly reduced during the heavy inspiratory loading trial (4.6±3.5 µM to 1.9±1.5 µM) post-training. There was no significant difference in oxy-, deoxy-, or total-haemoglobin and myoglobin during any of the other loading trials, from pre- to post-training, in either group. After inspiratory muscle training, highly-trained cyclists exhibited decreased locomotor and respiratory muscle deoxygenation during exercise with heavy inspiratory loading. These data suggest that inspiratory muscle training reduces oxygen extraction by the active respiratory and limb muscles, which may reflect changes in respiratory and locomotor muscle oxygen delivery

The effects of an experimental programme to support students’ autonomy on the overt behaviours of physical education teachers

Although the benefits of autonomy supportive behaviours are now well established in the literature, very few studies have attempted to train teachers to offer a greater autonomy support to their students. In fact, none of these studies has been carried out in physical education (PE). The purpose of this study is to test the effects of an autonomy-supportive training on overt behaviours of teaching among PE teachers. The experimental group included two PE teachers who were first educated on the benefits of an autonomy supportive style and then followed an individualised guidance programme during the 8 lessons of a teaching cycle. Their behaviours were observed and rated along 3 categories (i.e., autonomy supportive, neutral and controlling) and were subsequently compared to those of three teachers who formed the control condition. The results showed that teachers in the experimental group used more autonomy supportive and neutral behaviours than those in the control group, but no difference emerged in relation to controlling behaviours. We discuss the implications for schools of our findings

Anytime-valid confidence intervals for contingency tables and beyond

E variables are tools for designing tests that keep their type-I error guarantees under flexible sampling scenarios such as optional stopping and continuation. We extend the recently developed E variables for two-sample tests to general null hypotheses and the corresponding anytime-valid confidence sequences. Using the 2x2 contingency table (Bernoulli) setting as a running example, we provide simple implementations of these confidence sequences for linear and odds-ratio based effect size