Review of Waste Heat Utilisation from Data Centres

Rapidly increasing global internet traffic, mobile internet users and the number of Internet of Things (IoT) connections are driving exponential growth in demand for data centre and network services, which in turn is driving their electricity demand. Data centres now account for 3% of global electricity consumption and contribute to 4% of the global greenhouse gas emissions. This study discusses the potential of reusing the waste heat from data centres. An overview of imbedding heat recovery systems into data centres is presented. The implications of economic cost and energy efficient heat recovery systems in data centre buildings are also discussed. The main problems with implementing heat recovery systems in existing data centre designs are (i) high capital costs of investment and (ii) low temperatures of the waste heat. This study suggests alternatives that could allow data centre operators to utilise waste heat with more efficiencies. It also discusses how liquid-cooled data centres can be more efficient in utilising their waste heat than the air-cooled ones. One possible solution suggested here is that data centre operators can decrease their environmental impact by exporting waste heat to the external heat networks. The barriers in connecting datacentres to heat networks are discussed and suggestions to overcome those barriers have been provided

More than symbioses : orchid ecology ; with examples from the Sydney Region

The Orchidaceae are one of the largest and most diverse families of flowering plants. Orchids grow as terrestrial, lithophytic, epiphytic or climbing herbs but most orchids native to the Sydney Region can be placed in one of two categories. The first consists of terrestrial, deciduous plants that live in fire-prone environments, die back seasonally to dormant underground root tubers, possess exclusively subterranean roots, which die off as the plants become dormant, and belong to the subfamily Orchidoideae. The second consists of epiphytic or lithophytic, evergreen plants that live in fire-free environments, either lack specialised storage structures or possess succulent stems or leaves that are unprotected from fire, possess aerial roots that grow over the surface of, or free of, the substrate, and which do not die off seasonally, and belong to the subfamily Epidendroideae. Orchid seeds are numerous and tiny, lacking cotyledons and endosperm and containing minimal nutrient reserves. Although the seeds of some species can commence germination on their own, all rely on infection by mycorrhizal fungi, which may be species-specific, to grow beyond the earliest stages of development. Many epidendroid orchids are viable from an early stage without their mycorrhizal fungi but most orchidoid orchids rely, at least to some extent, on their mycorrhizal fungi throughout their lives. Some are completely parasitic on their fungi and have lost the ability to photosynthesize. Some orchids parasitize highly pathogenic mycorrhizal fungi and are thus indirectly parasitic on other plants. Most orchids have specialised relationships with pollinating animals, with many species each pollinated by only one species of insect. Deceptive pollination systems, in which the plants provide no tangible reward to their pollinators, are common in the Orchidaceae. The most common form of deceit is food mimicry, while at least a few taxa mimic insect brood sites. At least six lineages of Australian orchids have independently evolved sexual deception. In this syndrome, a flower mimics the female of the pollinating insect species. Male insects are attracted to the flower and attempt to mate with it, and pollinate it in the process. Little is known of most aspects of the population ecology of orchids native to the Sydney Region, especially their responses to fire. Such knowledge would be very useful in informing decisions in wildlife management

Furthering Indaziflam-Based Management Strategies of Three Invasive Annual Grasses in Northern Utah

Indaziflam is an herbicide highly recognized for its potential to effectively control weedy, winter germinating grasses, such as downy brome, as the herbicides prevents seed germination for several years. Unfortunately, most of these studies only capture the first 2-3 years of indaziflam’s 3-5 years soil activity. This thesis sought to better understand indaziflam’s long-term effects by monitoring both a healthy ecosystem and a degraded ecosystem for up to 5 years after indaziflam application. A secondary study was also conducted to better understand the potential of revegetation via reseeding in indaziflam treated soils. The study concluded that indaziflam very little long-term negative impact on the ecological health of either ecosystem. The study also found potential evidence that a layer of activated carbon applied between seeding and herbicide application can promote healthy plant germination in indaziflam treated soils

Predicting Surface Temperatures of Roads: Utilizing a Decaying Average in Forecasting

While being aware of the air temperature during the winter months is very important, many overlook the importance of the road temperature. Knowing the temperature of the road helps transportation departments decide whether or not salt will need to be distributed onto the road, as well as what type of salt. This research was conducted in order to better a forecast model on surface temperature predictions that was shown to be inaccurate. Data was used from the 2013–2014 winter from three cities across Indiana. The data included variables such as air and surface temperatures, precipitation, wind speed, and other variables that could affect the road temperature. These variables were recorded hourly for approximately 5 months. The data was run through both Python and R Studio in order to better visualize and compare the predictions to the observed data. Variables were weighted in different ways to find the variables that contributed most to temperature discrepancies in the forecast. After many tests, the results showed that adding a decaying average over the last 14 days to the predicted temperature yielded the strongest correlation in comparison to the other options available. These results permit additional degrees to be added to our prediction model that will ultimately lead to more accurate predictions, allowing transportation departments to use the predictions to implement in their daily tasks

The diagnosis of intra-uterine asphyxia by micro-blood analysis of the foetus in utero

Click on the link to view

Providing Public Transport for Tourists in Rural Areas

Travel, both to the destination area and within the area, accounts for a high proportion of tourism’s emissions. Yet, relatively little attention has been directed at reducing emissions through encouraging visitors to use public rather private transport. This paper reports the findings of surveys of bus passengers within British rural tourist areas and demonstrates how they bring extra visitors and spending to attractions, while reducing car use. It discusses the potential of using public transport to enhance the tourism offer and the problems, and some solutions, of funding such services. Recent developments are introduced

Viscous vortex flows

Several computational studies are currently being pursued that focus on various aspects of representing the entire lifetime of the viscous trailing vortex wakes generated by an aircraft. The formulation and subsequent near-wing development of the leading-edge vortices formed by a delta wing are being calculated at modest Reynolds numbers using a three-dimensional, time-dependent Navier-Stokes code. Another computational code was developed to focus on the roll-up, trajectory, and mutual interaction of trailing vortices further downstream from the wing using a two-dimensional, time-dependent, Navier-Stokes algorithm. To investigate the effect of a cross-wind ground shear flow on the drift and decay of the far-field trailing vortices, a code was developed that employs Euler equations along with matched asymptotic solutions for the decaying vortex filaments. And finally, to simulate the conditions far down stream after the onset of the Crow instability in the vortex wake, a full three-dimensional, time-dependent Navier-Stokes code was developed to study the behavior of interacting vortex rings