339 research outputs found
Carbon and energy performance of housing : a model and toolset for policy development applied to a local authority housing stock
The area of strategy formulation for energy and carbon performance of housing is coming under increasing focus. A model has been developed based on simulation results aligned with knowledge of the housing stock which can be used to calculate energy, carbon and cost results from a reduced number of input parameters. The context of the model can be varied to reflect different climates and patterns of use. The model is embedded in a user friendly java tool which can be used to give results for a dwelling or the housing stock of an organisation, region or country. It is possible to investigate the effect of housing upgrade options, future building regulations, climates, patterns of use, renewable energy systems etc. and support formulation of future policy. In this paper the tool is briefly described and an example given showing its application to a local authority rented housing stock
Project management under uncertainty
Morris' (1986) analysis of the factors affecting project success and failure is considered in relation to the psychology of judgement under uncertainty. A model is proposed whereby project managers may identify the specific circumstances in which human decision-making is prone to systematic error, and hence may apply a number of de-biasing techniques
The EDEM methodology for housing upgrade analysis, carbon and energy labelling and national policy development
The ESRU Domestic Energy Model (EDEM) has been developed in response to demand from policy makers for a tool to assist in analysis of options for improving carbon and energy performance of housing across a range of possible future technologies, behaviours and environmental factors. A major challenge is to comprehend the large variation in fabric, systems (heating, hot water, lighting and appliances) and behaviours across the housing stock as well as uncertainty over future trends. Existing static models have limited ability to represent dynamic behaviour while use of detailed simulation has been based on modelling only a small number of representative designs. To address these challenges, EDEM has been developed as an easy to use, Web based tool, built on detailed simulation models aligned with national house survey data. From pragmatic inputs, EDEM can determine energy use and carbon emissions at any scale, from individual dwelling to national housing stock. EDEM was used at the behest of the Scottish Building Standards Agency and South Ayrshire Council to quantify the impact of upgrades including new and renewable energy systems. EDEM was also used to rate energy/carbon performance of dwellings as required by the EU Directive (EU, 2002). This paper describes the evolving EDEM methodology, its structure and operation then presents findings from applications. While initial EDEM projects have been for the Scottish housing stock the methodology is structured to facilitate project development and application to other countries
Considering the impact of situation-specific motivations and constraints in the design of naturally ventilated and hybrid buildings
A simple logical model of the interaction between a building and its occupants is presented based on the principle that if free to do so, people will adjust their posture, clothing or available building controls (windows, blinds, doors, fans, and thermostats) with the aim of achieving or restoring comfort and reducing discomfort. These adjustments are related to building design in two ways: first the freedom to adjust depends on the availability and ease-of-use of control options; second the use of controls affects building comfort and energy performance. Hence it is essential that these interactions are considered in the design process. The model captures occupant use of controls in response to thermal stimuli (too warm, too cold etc.) and non-thermal stimuli (e.g. desire for fresh air). The situation-specific motivations and constraints on control use are represented through trigger temperatures at which control actions occur, motivations are included as negative constraints and incorporated into a single constraint value describing the specifics of each situation. The values of constraints are quantified for a range of existing buildings in Europe and Pakistan. The integration of the model within a design flow is proposed and the impact of different levels of constraints demonstrated. It is proposed that to minimise energy use and maximise comfort in naturally ventilated and hybrid buildings the designer should take the following steps: 1. Provide unconstrained low energy adaptive control options where possible, 2. Avoid problems with indoor air quality which provide motivations for excessive ventilation rates, 3. Incorporate situation-specific adaptive behaviour of occupants in design simulations, 4. Analyse the robustness of designs against variations in patterns of use and climate, and 5. Incorporate appropriate comfort standards into the operational building controls (e.g. BEMS)
HEAO 1 observations of the X-ray pulsar 4U1626-67
Results of an observation of the 7-s pulsar 4U1626-67 with the A2 experiments on HEAO 1 are reported. The phase-averaged X-ray spectra which change radically as a function of pulse phase. Included in this spectral change is the sudden appearance and subsequent decay of a continuum or emission feature with a mean energy of 19 keV which contains about 1/2 the power in this spectral range. Pulse timing results include a new determination of the pulse period and a factor 8 reduction in the upper limit for the light travel time for orbital periods between 1 and 7 hours. The findings for this system are discussed and compared with the general nature of pulsar spectra
In vitro faecal fermentation of Tritordeum breads and its effect on the human gut health
Spontaneous fermentation of Tritordeum flour enhances the nutritional potential of this hybrid cereal. However, the effect of consumption of Tritordeum sourdough bread (SDB) on gut health remains to be elucidated. This study investigated the effect of in vitro digestion and faecal fermentation of SDB compared to that of traditional baker's yeast (BYB) Tritordeum bread. After 24-h anaerobic faecal fermentation, both SDB and BYB (1% w/v) induced an increase in the relative abundances of Bifidobacterium, Megasphaera, Mitsuokella, and Phascolarctobacterium genera compared to baseline, while concentrations of acetate and butyrate were significantly higher at 24 h for SDB compared to those for BYB. Integrity of intestinal epithelium, as assessed through in vitro trans-epithelial electrical resistance (TEER) assay, was slightly increased after incubation with SDB fermentation supernatants, but not after incubation with BYB fermentation supernatants. The SDB stimulated in vitro mucosal immune response by inducing early secretion of inflammatory cytokines, IL-6 and TNF-α, followed by downregulation of the inflammatory trigger through induction of anti-inflammatory IL-10 expression. Overall, our findings suggest that Tritordeum sourdough can modulate gut microbiota fermentation activity and positively impact the gut health
Isolated neutron stars and studies of their interiors
In these lectures presented at Baikal summer school on physics of elementary
particles and astrophysics 2011, I present a wide view of neutron star
astrophysics with special attention paid to young isolated compact objects and
studies of the properties of neutron star interiors using astronomical methods.Comment: 28 pages, lecture notes for the Baikal-2011 summer school on physics
of elementary particles and astrophysic
Swift monitoring of the central X-ray source in RCW 103
The X-ray source 1E 161348-5055 lies at the centre of the 2-kyr-old supernova
remnant RCW 103. Owing to its 24-ks modulation, orders-of-magnitude flux
variability over a few months/years, and lack of an obvious optical
counterpart, 1E 161348-5055 defies assignment to any known class of X-ray
sources. Starting from April 2006, Swift observed 1E 161348-5055 with its X-ray
telescope for 2 ks approximately once per month. During the five years covered,
the source has remained in a quiescent state, with an average observed flux of
1.7e-12 erg/cm^2/s (1-10 keV), about 20 times lower than the historical maximum
attained in its 1999-2000 outburst. The long time-span of the Swift data allows
us to obtain an accurate measure of the period of 1E 161348-5055 [P =
24030.42(2) s] and to derive the first upper limit on its period derivative
(|dP/dt| < 1.6e-9 s/s at 3 sigma).Comment: 6 pages, 5 figures, accepted for publication in MNRAS. Figures 2,3
and 5 in reduced qualit
Six Years of Chandra Observations of Supernova Remnants
We present a review of the first six years of Chandra X-ray Observatory
observations of supernova remnants. From the official "first-light" observation
of Cassiopeia A that revealed for the first time the compact remnant of the
explosion, to the recent million-second spectrally-resolved observation that
revealed new details of the stellar composition and dynamics of the original
explosion, Chandra observations have provided new insights into the supernova
phenomenon. We present an admittedly biased overview of six years of these
observations, highlighting new discoveries made possible by Chandra's unique
capabilities.Comment: 82 pages, 28 figures, for the book Astrophysics Update
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