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241.
Laura Moss Derek Sleeman Malcolm Sim Malcolm Booth Malcolm Daniel Lyndsay Donaldson Charlotte Gilhooly Martin Hughes John Kinsella 《Knowledge》2010,23(4):309-315
Within the medical domain there are clear expectations as to how a patient should respond to treatments administered. When these responses are not observed it can be challenging for clinicians to understand the anomalous responses. The work reported here describes a tool which can detect anomalous patient responses to treatment and further suggest hypotheses to explain the anomaly. In order to develop this tool, we have undertaken a study to determine how Intensive Care Unit (ICU) clinicians identify anomalous patient responses; we then asked further clinicians to provide potential explanations for such anomalies. The high level reasoning deployed by the clinicians has been captured and generalised to form the procedural component of the ontology-driven tool. An evaluation has shown that the tool successfully reproduced the clinician’s hypotheses in the majority of cases. Finally, the paper concludes by describing planned extensions to this work. 相似文献
242.
243.
M. Anicete-Santos R. C. Lima E. Orhan M. A. M. A. Maurera L. G. P. Simões G. Souza P. S. PIZANI E. R. Leite J. A. Varela E. Longo 《Scientific Modeling and Simulation》2005,12(2-3):111-119
The SrWO4 (SWO) powders were synthesized by the polymeric precursor method and annealed at different temperatures. The SWO structure was obtained by X-ray diffraction and the corresponding photoluminescence (PL) spectra was measured. The PL results reveal that the structural order–disorder degree in the SWO lattice influences in the PL emission intensity. Only the structurally order–disordered samples present broad and intense PL band in the visible range. To understand the origin of this phenomenon, we performed quantum-mechanical calculations with crystalline and order–disordered SWO periodic models. Their electronic structures were analyzed in terms of band structure. The appearance of localized levels in the band gap of the order–disordered structure was evidenced and is a favorable condition for the intense PL to occur. 相似文献
244.
Eduardo A. A. G. Ribeiro R. Papaléo J. R. C. Guimarães 《Metallurgical and Materials Transactions A》1986,17(4):691-696
The effects of niobium additions to a “straight chromium” alloy were investigated by optical metallography and creep testing at 1033 K. The results indicate that by increasing the amount of interdendritic constituent, niobium adds to creep strength and fracture ductility. Optimum alloy design requires balancing niobium, chromium, and carbon content. 相似文献
245.
Rotaviruses and reoviruses are involved in human and animal diseases. It is known that both viruses penetrate the gastrointestinal tract but their interaction with phagocytic cells is unknown. To study this interaction, peritoneal resident phagocytic cells were used and rotavirus and reovirus replication in peritoneal phagocytic cells was observed. However, rotavirus replication in these cells led to the production of defective particles since MA-104 cells inoculated with rotavirus phagocytic cell lysate did not show any evidence of virus replication. On the basis of these results, we suggest that, although reovirus dissemination may be helped by these phagocytic cells, these cells may control rotavirus infection and probably contribute to the prevention of its dissemination. 相似文献
246.
This work describes the relationships observed between the porosity of fired ceramic test pieces and the raw materials contents
in the unfired mixture. The investigation was carried out using the mixture experiments design approach coupled with response
surface methodology, which enables the calculation of statistically significant models for the properties from a limited number
of experimental results. Ten formulations of a clay mixture, potash feldspar and quartz sand were processed in the laboratory
under fixed conditions, similar to those used on wall and floor tile industrial practice, and characterized. Closed porosity
(CP) was estimated from the analysis of back-scattered SEM photomicrographs, open porosity (OP) was calculated as the product
of bulk density and water absorption, and total porosity (TP) was calculated from OP and CP values. Characterization results
were used to calculate statistically significant and valid regression equations, relating those properties with the raw material
contents in the unfired mixture. For the particular raw materials and processing conditions used, the models clearly show
how quartz contributes to increasing OP and the crucial role played by feldspar when CP and TP are to be minimized (circa 3 vol.%), and how the clay content can counteract that effect and lead to maximum closed porosity (∼14 vol.%). 相似文献
247.
248.
Jorge Laine Joaquin Brito Francisco Severino Germán Castro Patricia Tacconi Simón Yunes José Cruz 《Catalysis Letters》1990,5(1):45-54
The effect of prereduction on CO oxidation activity of unsupported copper-chromite oxide catalysts was examined. Results were found to be in good agreement with two mechanisms for a surface copper enrichment due to CO prereduction which produced an activity increase in the copper-chromite catalyst. 相似文献
249.
Christian L.A. Sze Wey Chua Tian Yeong Sim Ling Xiang Liu 《IEEE transactions on instrumentation and measurement》2001,50(2):259-262
We have measured the hysteresis in output voltage arising from loss of power for three Fluke 732B dc voltage references. Continuously powering the internal temperature-controlled oven provides the best accuracy with such Zener-diode-based dc voltage references. Batteries are used to provide power continuity when shipping between laboratories. We have shown that for these particular instruments, an apparent hysteresis induced by humidity is likely to dominate any hysteresis arising from loss of battery power when transit between laboratories takes three days or more. Our conclusion is that as much, if not more, care needs to be taken when dealing with humidity than with loss of battery power when shipping between laboratories. When the highest accuracy of dc voltage comparison is required, it becomes necessary to apply voltage corrections using the measured values of humidity coefficients and the relative humidity occurring during transit 相似文献
250.
Amilton de Sousa LinsJr. Luís Felipe Guimarães de Souza Maria Cindra Fonseca 《Journal of Materials Engineering and Performance》2018,27(1):124-137
The use of high-strength and low-alloy steels, high design factors and increasingly stringent safety requirements have increased the operating pressure levels and, consequently, the need for further studies to avoid and prevent premature pipe failure. To evaluate the possibility of improving productivity in manual arc welding of this type of steel, this work characterizes the mechanical properties and residual stresses in API 5L X80 steel welded joints using the SMAW and FCAW processes. The residual stresses were analyzed using x-ray diffraction with the sin2 ψ method at the top and root of the welded joints in the longitudinal and transverse directions of the weld bead. The mechanical properties of the welded joints by both processes were characterized in terms of tensile strength, impact toughness and Vickers microhardness in the welded and shot peening conditions. A predominantly compressive residual stress was found, and shot peening increased the tensile strength and impact toughness in both welded joints. 相似文献