3,145 research outputs found
Victorian entertainments : "we are amused" : an exhibit illustrating Victorian entertainment.
Midwest Victorian Studies Association. Meeting (2007)published or submitted for publicationnot peer reviewe
Importance driven environment map sampling
In this paper we present an automatic and efficient method for supporting Image Based Lighting (IBL) for bidirectional methods which improves both the sampling of the environment, and the detection and sampling of important regions of the scene, such as windows and doors. These often have a small area proportional to that of the entire scene, so paths which pass through them are generated with a low probability. The method proposed in this paper improves this by taking into account view importance, and modifies the lighting distribution to use light transport information. This also automatically constructs a sampling distribution in locations which are relevant to the camera position, thereby improving sampling. Results are presented when our method is applied to bidirectional rendering techniques, in particular we show results for Bidirectional Path Tracing, Metropolis Light Transport and Progressive Photon Mapping. Efficiency results demonstrate speed up of orders of magnitude (depending on the rendering method used), when compared to other methods
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Anaesthesia in Ethiopia: providers' perspectives on the current state of the service
The improvement of surgical and anaesthetic safety in low-resource settings is hampered by a lack of reliable information on the current provision of these services. Ethiopia is one of the world's poorest countries and, despite large amounts of both foreign and domestic investment, still reports some of the worst health outcomes. However, information on anaesthesia and surgical provision is sparse. This work reproduces a questionnaire study, first used in Uganda in 2006, to survey practising anaesthetists regarding the current state of anaesthesia services across Ethiopia. The results indicate that a large proportion of centres remain unable to provide safe general, spinal, paediatric and obstetric anaesthesia, at all levels of hospital and across almost all of the country's regions. In addition to a lack of equipment and pharmaceuticals, anaesthetists report problems with professional recognition and a lack of access to continuing professional development as key barriers to service development
Development of a multi-lead trans-thoracic impedance pneumograph for heart rate variability studies
In this study, a device that measures respiratory tidal volume and ECG for use in heart rate variability studies, was designed, built and tested. The device developed is a Multi-Lead Trans-Thoracic Impedance Pneumograph, which determines tidal volume on a breath by breath basis, utilizing both hardware and software. It uses standard ECG electrodes which provide increased comfort and inability to the subject over traditional spirometry methods. The device operates similar to traditional bipolar impedance pneumographs except that instead of only one lead (electrode pair), four leads are acquired simultaneously using time-division multiplexing; providing data from different locations and vectors on the subjects chest.
Respiration, ECG and spirometry data were collected using the device from 6 normal, healthy subjects for several trials of normal and paced breathing. Results were correlated against the spirometry data to determine whether sufficient data are provided by the four leads and also to determine the accuracy of the device. It was concluded that combining data from all 4 leads using generalized additive modeling results in correlations in the range of 0.8 - 1.0, but more investigation is needed to determine usefulness in actual HRV applications
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