Cladding strategies for building-integrated photovoltaics

Photovoltaic cladding on the surfaces of commercial buildings has the potential for considerable reductions in carbon emissions due to embedded renewable power generation displacing conventional power utilization. In this paper, a model is described for the optimization of photovoltaic cladding densities on commercial building surfaces. The model uses a modified form of the ‘fill factor’ method for photovoltaic power supply coupled to new regression-based procedures for power demand estimation. An optimization is included based on a defined ‘mean index of satisfaction’ for matched power supply and demand (i.e., zero power exportation to the grid). The mean index of satisfaction directly translates to the reduction in carbon emission that might be expected over conventional power use. On clear days throughout the year, reductions of conventional power use of at least 60% can be achieved with an optimum cladding pattern targeted to lighting and small power load demands

Habitability of known exoplanetary systems based on measured stellar properties

At present, because of observational selection effects, we know of no exoplanetary systems with any planetary masses close to that of the Earth. We have therefore used computer models to see whether such planets could be dynamically stable in the presence of the more massive planets known to be present, and in particular whether planets with roughly an Earth mass could remain confined to the classical habitable zone (HZ) for long enough for life to have emerged. Measured stellar properties have been used to determine for each system the present location of the HZ. We have also determined the critical distances from the orbit of each giant planet within which an Earth-mass planet would suffer large orbital changes. We then evaluated the present habitability of each and every exoplanetary system by examining the penetration of these critical distances into the HZ. The critical distances can be obtained by extensive computer modelling of an exoplanetary system. This is far too time consuming to apply to all of the 150 or so systems already known, and to keep up with the latest discoveries. Therefore, in earlier work we studied a few systems in great detail, and developed a speedier means of obtaining the critical distances. We summarize this comparatively quick method here. We can then evaluate comparatively quickly the present habitability of each exoplanetary system by examining the penetration of the critical distance(s) into the HZ. The results are encouraging for astrobiology.Comment: Accepted for publication by The Astrophysical Journal. A few revisions have been made following suggestions by the refere

Space Trajectory Error Analysis Program (STEAP) for halo orbit missions. Volume 2: Programmer's manual

The six month effort was responsible for the development, test, conversion, and documentation of computer software for the mission analysis of missions to halo orbits about libration points in the earth-sun system. The software consisting of two programs called NOMNAL and ERRAN is part of the Space Trajectories Error Analysis Programs. The program NOMNAL targets a transfer trajectory from earth on a given launch date to a specified halo orbit on a required arrival date. Either impulsive or finite thrust insertion maneuvers into halo orbit are permitted by the program. The transfer trajectory is consistent with a realistic launch profile input by the user. The second program ERRAN conducts error analyses of the targeted transfer trajectory. Measurements including range, doppler, star-planet angles, and apparent planet diameter are processed in a Kalman-Schmidt filter to determine the trajectory knowledge uncertainty

Renewable energy in remote communities

This article is the result of a competitively tendered University-funded project, this brings together two major Government Policy areas: sustainable communities and use of carbon fuels, and is aimed at influencing the policy debate on the difficulties of linking remote communities to renewable energy production because of poor distribution networks. Linkage with the Sustainable Communities agenda is an essential ingredient, as the proposal is that the renewable energy technologies will be installed and maintained by the communities themselves

Sharks of the order Carcharhiniformes from the British Coniacian, Santonian and Campanian (Upper Cretaceous).

Bulk sampling of phosphate-rich horizons within the British Coniacian to Campanian (Upper Cretaceous) yielded very large samples of shark and ray teeth. All of these samples yielded teeth of diverse members of the Carcharhiniformes, which commonly dominate the fauna. The following species are recorded and described: Pseudoscyliorhinus reussi (Herman, 1977) comb. nov., Crassescyliorhinus germanicus (Herman, 1982) gen. nov., Scyliorhinus elongatus (Davis, 1887), Scyliorhinus brumarivulensis sp. nov., ? Palaeoscyllium sp., Prohaploblepharus riegrafi (Müller, 1989) gen. nov., ? Cretascyliorhinus sp., Scyliorhinidae inc. sedis 1, Scyliorhinidae inc. sedis 2, Pteroscyllium hermani sp. nov., Protoscyliorhinus sp., Leptocharias cretaceus sp. nov., Palaeogaleus havreensis Herman, 1977, Paratriakis subserratus sp. nov., Paratriakis tenuis sp. nov., Paratriakis sp. indet. and ? Loxodon sp. Taxa belonging to the families ?Proscylliidae, Leptochariidae, and Carcharhinidae are described from the Cretaceous for the first time. The evolutionary and palaeoecological implications of these newly recognised faunas are discussed

Lung Cancer Metastasis Presenting as a Solitary Skull Mass

Lung cancer has been well documented to spread to bone and the axial skeleton after metastasis to adjacent organs. Bony metastasis is not, however, the typical presenting manifestation. The differential diagnosis for a tissue mass on the skull should warrant a workup for metastatic disease. Bony metastasis plays an important role in treatment and disease management. We report an exceptionally rare case of stage IV lung adenocarcinoma that presented with a solitary skull metastasis and a significant soft-tissue component. The lesion was treated by excision via craniotomy and subsequent medical management of the adenocarcinoma. This case illustrates a very rare presentation of lung adenocarcinoma and also represents what the authors believe to be the first report of a solitary skull mass originating from a lung primary. We also present a review of the literature surrounding bony metastasis to the skull and implications for patient care

Eye movements during scene inspection: A test of the saliency map hypothesis

What attracts attention when we inspect a scene? Two experiments recorded eye movements while viewers inspected pictures of natural office scenes in which two objects of interest were placed. One object had low contour density and uniform colouring (a piece of fruit), relative to another that was visually complex (for example, coffee mugs and commercial packages). In each picture the visually complex object had the highest visual saliency according to the Itti and Koch algorithm. Two experiments modified the task while the pictures were inspected, to determine whether visual saliency is invariably dominant in determining the pattern of fixations, or whether the purpose of inspection can provide a cognitive override that renders saliency secondary. In the first experiment viewers inspected the scene in preparation for a memory task, and the more complex objects were potent in attracting early fixations, in support of a saliency map model of scene inspection. In the second experiment viewers were set the task of detecting the presence of a low saliency target, and the effect of a high saliency distractor was negligible, supporting a model in which the saliency map can be built with cognitive influences that override low-level visual features