Energy use and indoor environment in a sample of monitored domestic buildings in the UK

This paper is based on the low-cost approaches and transferable techniques that were applied in a PhD reserch project on energy-related occupancy activities. The strengths of qualitative and quantitative research strategies were combined for the study of this socio-technical research topic. Long-term field measurement was conducted for data acquisition using self-configured monitoring schemes. Case study was selected as the research approach. Building characteristics and household features in each case study group were purposefully selected to deploy same-standard monitoring schemes. Comparable monitoring results were pre-processed following identical procedures to implement the selected data analysis methods. The inspection results provided the researcher and the associated project partners with a novel perspective to interpret the difference in actual energy consumption and indoor environment within and between the case study groups. The research methodology and moitoring approach are covered in this paper that also presents the macro-scale monitoring results of energy use and indoor environment in two case study groups. The micro-scale presentation and algorithm-based examination will be covered in other academic papers. This paper demonstrates the huge potential for some commonly applied building assessment methods to be improved by objectively considering currently overlooked aspects, such as the low-tech design and construction of heavy-weight thermal mass houses and the largely varied occupancy activities. Future work relating to the comparison of actual monitoring data with simulation results is pointed out at the end of the paper

Stochastic areas of diffusions and applications in risk theory

In this paper we study the stochastic area swept by a regular time-homogeneous diffusion till a stopping time. This unifies some recent literature in this area. Through stochastic time change we establish a link between the stochastic area and the stopping time of another associated time-homogeneous diffusion. Then we characterize the Laplace transform of the stochastic area in terms of the eigenfunctions of the associated diffusion. We also explicitly obtain the integer moments of the stochastic area in terms of scale and speed densities of the associated diffusion. Specifically we study in detail three stopping times: the first passage time to a constant level, the first drawdown time and the Azema-Yor stopping time. We also study the total occupation area of the diffusion below a constant level. We show applications of the results to a new structural model of default (Yildirim 2006), the Omega risk model of bankruptcy in risk analysis (Gerber, Shiu and Yang 2012), and a diffusion risk model with surplus-dependent tax (Albrecher and Hipp 2007, Li, Tang and Zhou 2013)

Shock Waves: From Gas Dynamics to Granular Flows

This short article briefly discusses some aspects in shock wave studies in recent years, in particular on the difference between gas dynamics and granular flow problems. It compares the relations of oblique shock waves, where weak, strong and detached shock waves can be observed in both gas dynamic and granular conditions. If the upstream Froude number of granular flow becomes infinitely large a granular shock wave would still remain attached and oblique around a wedge angle near 90°, however an attached gas dynamic shock wave is limited by a maximum wedge angle, say, of 30°. On the other hand, the shock standoff distance for a detached granular shock wave tends to become infinitely small with the increase of the upstream Froude number since it is associated with the flow height ratio across the shock wave