Conditional variances in UK regional house prices

The returns of house price indices for the 13 UK regions are modelled using time series processes, including conditional variances. The first conclusion is that the UK follows the USA, with some regions displaying time-varying variances and others with constant variances. Secondly, there is limited evidence of an asymmetric component in six of the seven regions displaying autoregressive conditional heteroskedasticity. Thirdly, the results suggest that there are three distinct housing markets in the UK, based on common structures within their mean and variance processes, and that South West England is the region driving the other time-varying variances. Variances conditionnelles dans les prix regionaux de l'immobilier au Royaume-Uni Resume Les resultats de l'indice des prix de l'immobilier pour les 13 regions du Royaume-Uni sont modelises ici au moyen de procedes de series chronologiques, y compris des variances conditionnelles. La premiere conclusion est que le Royaume-Uni suit les Etats-Unis, certaines regions presentant des variances temporelles, d'autres des variances constantes. Deuxiemement, on releve peu de traces d'un composant asymetrique dans six des sept regions presentant une heteroscedasticite conditionnelle autoregressive. Troisiemement, les resultats indiquent qu'il y aurait trois marches de l'immobilier distincts au Royaume-Uni, sur la base de structures communes dans le cadre de leurs procedes moyens et de variance, et que le sud-ouest de l'Angleterre est la region qui dynamise les autres variances temporelles. Varianzas condicionales en los precios regionales de la vivienda en el Reino Unido Extracto Las cifras de los indices de precios de la vivienda en 13 regiones del Reino Unido se modelan utilizando procesos de series temporales, incluyendo varianzas condicionales. La primera conclusion es que el Reino Unido sigue a los EE UU, con varias regiones que muestran varianzas fluctuantes con el tiempo y otras con varianzas constantes. En segundo lugar, existe evidencia limitada de un componente asimetrico en seis de las siete regiones que muestran una heteroesquedacidad condicional autorregresiva. En tercer lugar, los resultados sugieren que existen tres mercados distintivos de la vivienda en el Reino Unido, basados en estructuras comunes dentro de sus procesos de media y varianza, y que el sudoeste de Inglaterra es la region que dirige las otras varianzas fluctuantes con el tiemp

Thermal Transients in District Heating Systems

Heat fluxes in a district heating pipeline systems need to be controlled on the scale from minutes to an hour to adjust to evolving demand. There are two principal ways to control the heat flux - keep temperature fixed but adjust velocity of the carrier (typically water) or keep the velocity flow steady but then adjust temperature at the heat producing source (heat plant). We study the latter scenario, commonly used for operations in Russia and Nordic countries, and analyze dynamics of the heat front as it propagates through the system. Steady velocity flows in the district heating pipelines are typically turbulent and incompressible. Changes in the heat, on either consumption or production sides, lead to slow transients which last from tens of minutes to hours. We classify relevant physical phenomena in a single pipe, e.g. turbulent spread of the turbulent front. We then explain how to describe dynamics of temperature and heat flux evolution over a network efficiently and illustrate the network solution on a simple example involving one producer and one consumer of heat connected by "hot" and "cold" pipes. We conclude the manuscript motivating future research directions.Comment: 31 pages, 7 figure

Energy and Accuracy Trade-Offs in Accelerometry-Based Activity Recognition

Driven by real-world applications such as fitness, wellbeing and healthcare, accelerometry-based activity recognition has been widely studied to provide context-awareness to future pervasive technologies. Accurate recognition and energy efficiency are key issues in enabling long-term and unobtrusive monitoring. While the majority of accelerometry-based activity recognition systems stream data to a central point for processing, some solutions process data locally on the sensor node to save energy. In this paper, we investigate the trade-offs between classification accuracy and energy efficiency by comparing on- and off-node schemes. An empirical energy model is presented and used to evaluate the energy efficiency of both systems, and a practical case study (monitoring the physical activities of office workers) is developed to evaluate the effect on classification accuracy. The results show a 40% energy saving can be obtained with a 13% reduction in classification accuracy, but this performance depends heavily on the wearer’s activity

Why the “Hoax” Paper of Baldwin (2018) Should Be Reinstated

In 2018, a peer-reviewed article was published under the name of Richard Baldwin in which the author presented a critique of fat exclusion and advocated “fat bodybuilding” as a sport. Some months later, it became apparent that the article was intended as a hoax written to raise awareness to, or “expose”, a certain ideology promoted by some academics. As a result, the editors retracted the article. Using the principles of methodological behaviorism, and other hoax or hoax-like articles, I will argue that the thoughts and opinions held by any author are not important to the argument they present. I will also argue that this form of reflexive ethnography is too problematic to serve as a method of enquiry. I will therefore conclude that the Baldwin article should be reinstated

Effect of organic crop rotations on long-term development of the weed seedbank

Changes in the weed seedbank were monitored between 1991 and 1998 in two experiments that were established to compare organic crop rotations at two sites in NE Scotland. Two rotations, replicated twice at each site, were compared and all courses of both rotations were present every year. There were relatively minor changes in weed species diversity over time, but major changes in seedbank abundance. Weed seed numbers were relatively low in rotations with a high proportion of grass/clover ley. Differences in level of seedbank across the rotation were relatively predictable at Tulloch but much less so at Woodside where factors such as the effect of the grass/clover ley seemed to play a lesser role. Other factors, such as weather and its influence on the effectiveness of weed control operations, and higher populations of ground-living arthropods, may be affecting the Woodside seedbanks

Training Creative Teams

This master’s project presents creative principles, frameworks, materials, and online methodologies for the development of a new or updated training program within a team environment. Inspiration for the project was sourced from creativity research papers, publicly available training guides, popular business books, and my personal experience co-leading the Global Citizen Leadership program in partnership with the Center for Creative Leadership at two universities in India. The tools and materials shared throughout the project were focused towards the personal development of facilitation and core skills for the 55 person staff at SEEK Company. Creativity principles of autonomy, team resource, and failure were used for the creation of all materials and training frameworks. Key findings have been shared to help extend the project’s impact to a broader set of organizations and learning environments

Structure and chemistry in the northwestern condensation of the Serpens molecular cloud core

We present single-dish and interferometric observations of gas and dust in the core of the Serpens molecular cloud, focusing on the northwestern condensation. Single-dish molecular line observations are used to probe the structure and chemistry of the condensation while high-resolution images of CS and CH_(3)0H are combined with continuum observations from λ = 1.3 mm to λ = 3.5 cm to study the subcondensations and overall distribution of dust. For the northwestern condensation, we derive a characteristic density of 3 x 10^5 cm^(-3) and an estimated total mass of approximately 70 M_⊙. We find compact molecular emission associated with the far-infrared source S68 FIRS 1, and with a newly detected subcondensation named S68 N. Comparison of the large-and small-scale emission reveals that most of the material in the northwest condensation is not directly associated with these compact sources, suggesting a youthful age for this region. CO J = 1 approaches 0 observations indicate widespread outflow activity. However, no unique association of embedded objects with outflows is possible with our observations. The SiO emission is found to be extended with the overall emission centered about S68 FIRS 1; the offset of the peak emission from all of the known continuum sources and the coincidence between the blueshifted SiO emission and blueshifted high-velocity gas traced by CO and CS is consistent with formation of SiO in shocks. Derived abundances of CO and HCO^(+) are consistent with quiescent and other star-forming regions while CS, HCN, and H2CO abundances indicate mild depletions within the condensation. Spectral energy distribution fits to S68 FIRS 1 indicate a modest luminosity (50-60 L_⊙), implying that it is a low-mass (0.5-3 M_⊙) young stellar object. Radio continuum observations of the triple source toward S68 FIRS 1 indicate that the lobe emission is varying on timescales ≤ 1 yr while the central component is relatively constant over ~14 yr. The nature of a newly detected compact emission region, S68 N, is less certain due to the absence of firm continuum detections; based on its low luminosity (<5 L_⊙) and strong molecular emission, S68 N may be prestellar subcondensation of gas and dust

Growth of White Spruce, Picea glauca, Seedlings in Relation to Microenvironmental Conditions in a Forest-Prairie Ecotone of Southwestern Manitoba

The influence of microenvironmental conditions on the growth performance (i.e., diameter and height growth) of White Spruce [Picea glauca (Moench) Voss] seedlings was examined within three contrasting habitats: White Spruce tree islands, open prairies and Trembling Aspen (Populus tremuloides Michx.) groves. These habitats exist within a disjunct occurrence of White Spruce at its southern limit of distribution in three mixed-grass prairie preserves in the Spruce Woods Provincial Park within the forest-prairie ecotone of southwestern Manitoba. Microenvironmental measurements (i.e., light, temperature, relative humidity, soil moisture) were obtained on 10 sites in each of the three habitats and growth characteristics of 60 White Spruce seedlings were measured in each of three habitats. Higher light and soil temperature conditions occurred within the open prairie. In contrast, lower light and soil temperature conditions occurred under the tree canopy of aspen groves and the northern aspect of spruce islands, which moderated the effect of the dry regional climate. Height growth did not vary significantly among the three habitats. The greater diameter growth and decreased slenderness of White Spruce seedlings in the open versus the shaded habitats appears to be a result of increased photosynthesis at higher light intensity and may also represent a morphological adaptation to withstand the effect of increased wind exposure. The increased slenderness of White Spruce in the shaded habitats appears to be a morphological adaptation of increasing carbon allocation towards height growth and thus maximizing effective competition for light

Climatic Sensitivity of a Mixed Forest Association of White Spruce and Trembling Aspen at Their Southern Range Limit

Climatic sensitivity of white spruce (Picea glauca (Moench) Voss) was examined growing in association with trembling aspen (Populus tremuloides Michx.) at their southern limit of distribution in a transitional ecotone between the southern boreal forest and northern prairie region. The study was carried out in the Spruce Woods Provincial Park (SWPP) located in southwestern Manitoba, Canada. The dry regional climate restricted trembling aspen growth during the growing season via moisture deficiency and temperature induced drought stress. Warm, mild winters also negatively affected radial growth of trembling aspen. Growth of white spruce was moderated by conditions within the aspen stands as radial growth patterns showed low variability from year to year, a low common growth signal, and a stronger response to temperature than to precipitation. Nonetheless, the dry regional climate still restricted growth of white spruce during the growing season via temperature induced drought stress. The findings of the study for white spruce support the stress gradient hypothesis in which facilitative interactions between tree species are expected under harsher environmental conditions

Design and performance of BNR activated sludge systems with flat sheet membranes for solid-liquid separation

Includes bibliographical references.Wastewater treatment technologies have developed out of the need to protect receiving water bodies from the increasingly concentrated municipal and industrial waste streams generated through human activity. Of the methods available to clean wastewaters, biological nutrient removal (BNR) activated sludge (AS) is applied throughout South Africa and internationally as it has many advantages, notably it is cheaper to operate, does not introduce salinity into the water and is a simple and robust process. One of the key steps in the BNR AS process is the separation of biomass from the water. This is traditionally achieved by means of secondary settling tanks (SSTs), however recently the use of membranes for solid-liquid separation has gained popularity for the following reasons: Membranes are able to retain all solids and thus are insensitive to the settling characteristics of sludges, • they can be run at high concentrations and hence smaller reactor volumes are required, • membranes can produce a guaranteed high quality effluent free of pathogens and in some cases viruses too. • Additionally smaller reactor volumes and the obviation of SSTs allow a substantial wastewater treatment plant footprint reduction. Hence the combination of membranes in BNR AS is being increasingly applied. where much research has been conducted on the performance of membranes. The majority of the research has focused on the physical membrane performance, investigating the mechanisms of fouling, or on the membrane biological reactor (MBR) performance in removing organic compounds or nitrogen compounds from wastewater. There are however few case studies investigating BNR using membranes despite speculation that the inclusion of membranes may indeed affect the nature of the activated sludge biomass (Witzig et al., 2002)