Towards autonomous updating of world models in location-aware spaces

Location-aware systems are systems where location information is used as a rich source of context to enable computers to interact and react to their environment. To date, research involving such systems in the indoor environment has concentrated on the development of cheap, realisable, accurate location systems rather than the continued maintenance of the associated world model needed to derive context. This paper characterises the problems relating to world models that have been observed in a real deployment of a location-aware system. It develops a framework that separates the task of synchronising the real and virtual worlds into two—first monitoring to identify coarse regions of inconsistency, and the second accurate updating of these regions. The paper details methods by which the monitoring can be achieved without the cost of deploying specialised sensors, but rather through collating and analysing human movement patterns and raw location data. It presents an overview of the framework for monitoring, an in-depth case study with experimental results from a deployed system, and a discussion of how accurate updates could be achieved once inconsistent regions are identified.     

Infrared radiance and temperature measurements on the mesa side of Gunn diodes

Radiance and temperature profiles for the first time have been measured along the mesa side of Gunn diode samples, using an infrared microscope with a spatial resolution of 2.5 mum. Bulk heat generation occurs in the transit region, but measurements have shown a small amount of additional ohmic heating in the substrate layer, which will influence the maximum temperature of the device. The presented thermal measurements have been used to improve the existing thermal finite-element model of the diode. The measurements also represent an alternative method to obtain a more accurate temperature of the diode top contact without coating the sample with a high emissivity layer.     

Ambient wood smoke exposure and respiratory symptoms in Tasmania, Australia

Wood smoke exposure has been associated with adverse respiratory health outcomes, with much of the current research focused on wood smoke from domestic heating and cooking. This study examined the association between respiratory symptoms and outdoor wood smoke in Launceston, Tasmania, where ~ 30% of homes use wood burners for domestic heating. This ecological study examined data from participants of the 2004 Tasmanian Longitudinal Health Study postal survey and compared the prevalence of respiratory symptoms in Launceston (n = 601) with that in Hobart (n = 1071), a larger Tasmanian city with much less wood smoke. Multivariate logistic regression models were used to investigate the associations of interest while adjusting for gender, atopy, history of allergic disease and current smoking status. There were no significant differences in symptom prevalence between Launceston and Hobart. Two subgroup analyses, which examined participants with pre-existing chronic respiratory disease, and those who reported actively using a wood burner in their home, also did not find significant differences. Any impact of wood smoke on non-specific respiratory symptoms might have been overshadowed by other important determinants of respiratory health, such as vehicle exhaust and tobacco smoking, or were too small to have been detected. However, the lack of detectable differences in symptom prevalence might also reflect the success of regulatory action by local governments to reduce wood smoke emissions in Launceston. The results of other epidemiological studies support an association between ambient wood smoke exposure and adverse respiratory health. Further investigations of wood smoke exposure in Australian settings are needed to investigate the lack of significant associations found in this study, especially studies of indoor air quality and health impacts in children and elderly populations.     

NEMA Standards for Induction Motors and Their Application to the Cement Industry

Familiarity with NEMA standards and the influence of the power supply on the motor-load system permits the user to make the necessary decision as to whether a standard or special motor is needed for his particular application. This paper highlights the more important aspects of NEMA standards for ac induction motors from the application engineer's standpoint and the effect of the power supply and the load on motor characteristics.     

The readability of currently used surgical/procedure consent forms in the United States

We report a patient diagnosed prenatally on routine fetal ultrasound, at 30 weeks' gestation, with subdural haemorrhage. The mother had suffered a mild abdominal trauma and had Factor XI deficiency; however, both were felt to be aetiologically insignificant. Prenatal follow-up showed a complete resolution of the haematoma and no postnatal sequelae have been noted to date. The aetiologies and outcomes in the few previously reported cases are reviewed and compared with our case.     

Programming with objects

The primary question about object programming is “How is it better than traditional programming methods?” The following answers are typically given: increased productivity, more code reuse, better management of complexity, and encouragement of a healthy programming style. However these advantages may not be evident until one understands the philosophy behind an object. Furthermore, when trying to learn an object based language, the first obstacles appear to be terminology and language syntax. This is deceiving since the real obstacle is learning to think of a program in terms of objects rather than data and subroutines. The distinction is as subtle as it is powerful. The present authors present some terms and ideas about programming with objects without emphasizing any specific programming language     

Alkali metal cation-induced destabilization of gas-phase protein-ligand complexes: consequences and prevention

Electrospray ionization, now a well established technique for studying noncovalent protein-ligand interactions, is prone to production of alkali metal adducts. Here it is shown that this adduction significantly destabilizes the interactions between two model proteins and their ligands and that destabilization correlates with cation size. For both the [FKBP·FK506] and [lysozyme·NAG(n)] systems, dissociation of the metalated complex occurs at markedly lower collision energies than their purely protonated equivalents. Dependency upon size of the metal(+) demonstrates the importance of electrostatic charge density during the dissociation process. Differences in the gas phase basicities (GBapp) of the multiply charged protein ions and proton and sodium affinities of the ligands explain the observed charge partitioning during dissociation of the complexes. Ion mobility-mass spectrometry measurements demonstrate that metal cation adduction does not induce a significant increase in unfolding of the polypeptides, indicating that this is not the principal mechanism responsible for destabilization. Destabilizing effects can be largely reduced by exposing the electrospray to solvent (e.g., acetonitrile) vapor, a method that acts to reduce the amount of adduct formation as well as decrease the charge states of the resulting ions. This approach leads to more accurate determination of apparent K(D)s in the presence of trace alkali metals.