Computational forms for binary particle interactions at different levels of anisotropy

Particle interactions are key elements of many dynamical systems. In the context of systems described by a Boltzmann equation, such interactions may be described by a collision integral, a multidimensional integral over the momentum-phase space of the interaction. This integral is often simplified by assuming isotropic particle distributions; however, such an assumption places constraints on the dynamics of the system. This paper presents computational forms of the collision integral for relativistic, binary interactions at three levels of anisotropy, including a novel form in the isotropic case. All these forms are split into two parts, an absorption and an emission spectrum, which may be pre-calculated via numerical integration for simulation purposes. We demonstrate the use of these forms by comparison with the analytically integrated, isotropic emission spectrum of electron–positron annihilation, which are shown to agree to numerical precision. The emission spectrum is then further extended to axisymmetric particle distributions, where two-dimensional spectral maps can be generated to provide new insight

Big data based intelligent decision support system for sustainable regional development

Timely intelligent decision making is increasingly important for modern society. With the availability of big data and advanced artificial intelligence in decision making, more objective and evidence-based quantitative smart decisions can be made in a timely manner. This research proposed a big data based intelligent decision support system (B-IDSS) for sustainable business development. The system can be used by both the government agencies and corporate business (e.g. farms. mining) in advanced planning, collaboration and management. This paper also addresses the performance optimization as bilevel decision-making problem with one leader and multiple followers. An extended Kuhn-Tucker approach is introduced as one of the algorithms that can be adapted in the system

Religion-related discourse:a critical approach to non-religion in Edinburgh's Southside

This thesis has been undertaken to critically engage with, reframe and rehabilitate a burgeoning body of contemporary research on ‘non-religion’ within the critical academic study of ‘religion’, and to explore the benefits of such a reframing for empirical research. I begin by critically introducing research on ‘non-religion’ and identifying a number of key problems which directly relate to ever-raging debates surrounding the definition of ‘religion’. I then justify my chosen approach—discourse analysis—and provide a discursive re-reading of studies of ‘non-religion’, arguing that it should be approached as part of a ‘religion-related field’, before outlining the theoretical questions addressed in the thesis. I argue for locality as a productive means through which to examine religion-related discourse, justify the selection of Edinburgh’s Southside as my field site, and introduce my data sources and the specifics of my analytical approach. Chapter 4 presents my analysis of the Peoples of Edinburgh Project (PEP), conducted in the mid-1990s, while Chapters 5–7 present the analysis of my own empirical work in the contemporary Southside, and place this into conversation with the PEP. In these chapters I demonstrate that the religion-related field is entangled with a variety of powerful discourses that are inflected by the Southside’s local and national particularity. I also demonstrate the importance of looking beyond the supposed ‘religious’ or ‘non-religious’ character of discourses, in order to assess the underlying structures and entanglements, and to avoid unjustifiably reifying the religion-related field. In some cases the ‘non-religious’ is implicit in the subject position of actors utilizing religion-related discourse. It also appears that being positioned as ‘religious’ or ‘non-religious’ means more in certain circumstances than in others. Furthermore, I reflect on the notion of religious ‘indifference’, arguing that, in some instances, the performance of indifference is a tactic for coping with contextually meaningful difference

Towards the Fully-coupled Numerical Modelling of Floating Wind Turbines

AbstractThe aim of this study is to model the interactions between fluids and solids using fully nonlinear models. Non- linearity is important in the context of floating wind turbines, for example, to model breaking waves impacting on the structure and the effect of the solid's elasticity. The fluid- and solid-dynamics equations are solved using two unstructured finite-element models, which are coupled at every time step. Importantly, the coupling ensures that the action-reaction principle is satisfied at a discrete level, independently of the order of representation of the discrete fields. To the authors’ knowledge, the present algorithm is novel in that it can simultaneously handle: (i) non- matching fluid and solid meshes, (ii) different polynomial orders of the basis functions on each mesh, and (iii) different fluid and solid time steps. First, results are shown for the flow past a fixed actuator-disk immersed in a uniform flow and representing a wind turbine. The present numerical results for the velocity deficit induced by the disk are shown to be in good agreement with the semi-analytical solution, for three values of thrust coefficients. The presence of a non-zero fluid viscosity in the numerical simulation affects wake recovery and fluid entrainment around the disk. Second, the dynamic response of a cylindrical pile is computed when placed at an interface between air and water. The results qualitatively demonstrate that the present models are applicable to the modelling of multiple fluids interacting with a floating solid. This work provides a first-step towards the fully coupled simulation of offshore wind turbines supported by a floating spar

Acoustic characterization of sensors used for marine environmental monitoring

Acknowledgements The authors wish to acknowledge Benjamin Brand for his assistance with the Acoustic Test Facility set-up, Jessica Noe for her assistance designing sonar mounts, James Joslin for his assistance with cables for sonar operation, and Mark Wood for his assistance with icListen hydrophones. This study would not have been possible without their contributions. Funding This work was funded by the US Department of Energy [grant number DE-EE0007827]. Emma Cotter is supported by a National Science Foundation Graduate Research Fellowship [grant number DGE-1762114].Peer reviewedPostprin

Experimental Study of the Heat Pump with Variable Speed Compressor for Domestic Heat Load Applications

Capacity control for heat pump (HP) systems is essential to efficiently meet variable heating loads in domestic buildings. A low-to-medium temperature hot water supply within a 30 oC-55 oC range is commonly required for domestic heating load applications. In this study, the performance of a variable speed air source heat pump (ASHP) system was studied in the laboratory under a series of ambient conditions at -2 oC, 2 oC, 7 oC and 15oC, examining performance at different water supplying temperatures (WST) of 30 oC, 35 oC, 40 oC, 45 oC, 50 oC, and 55 oC. The performance of the variable speed HP system was evaluated in a conditioning chamber at the above-mentioned ambient temperatures and corresponding humidity levels as per BS EN 14511 standards. The HP performance at six different heating capacities of 18kW, 15kW,12kW, 9kW, 6kW, and 3kW was measured and evaluated via coefficient of performance (CoP) values. The CoP values changes according to the load, water supply temperature (WST) and ambient temperature conditions. The CoP values for fixed ambient temperature conditions and WST i.e., 7 oC and WST 30 oC (7A30W) at 15kW, 12kW, 9kW, 6kW, and 3kW were found to be 3.56, 3.83,4.35, 4.19, and 3.39, respectively. The corresponding frequency of operation was 112.25Hz, 105.87Hz, 81.57Hz, 61.05Hz, 37.64Hz, 18.75 Hz with an absolute percentage difference of 87.01%, 76.45%, 35.95%, 1.75%, 37.26%, and 68.75% to that of the nominal frequency of 60Hz. The trend was similar by changing WST to 35 oC, 40 oC, 45 oC, 50 oC and 55 oC, but with lower CoP values and a smaller variation range. The difference between water inlet and supply temperature (delta T) is another important parameter in domestic heat load applications, and this study also presents results of comparative testing of delta T of 5, 10 and 20 at ambient conditions of 15 oC for WST of 40 oC, 45 oC, 50 oC, and 55 oC. The experimental results indicate that this variable speed-based HP system has the potential to meet different domestic heating demands within a range of WST and ambient conditions