Earth observations and global change decision making: A special bibliography, 1991

The first section of the bibliography contains 294 bibliographic citations and abstracts of relevant reports, articles, and documents announced in 'Scientific and Technical Aerospace Reports (STAR)' and 'International Aerospace Abstracts (IAA)'. These abstracts are categorized by the following major subject divisions: aeronautics, astronautics, chemistry and materials, engineering, geosciences, life sciences, mathematical and computer sciences, physics, social sciences, space sciences and general. Following the abstract section, seven indexes are provided for further assistance

Energy efficiency in content delivery networks

The increasing popularity of bandwidth-intensive video Internet services has positioned Content Distribution Networks (CDNs) in the limelight as the emerging provider platforms for video delivery. The goal of CDNs is to maximise the availability of content in the network while maintaining the quality of experience expected by users. This is a challenging task due to the scattered nature of video content sources and destinations. Furthermore, the high energy consumption associated with content distribution calls for developing energy-efficient solutions able to cater for the future Internet. This thesis addresses the problem of content placement and update while considering energy consumption in CDNs. First, this work contributed a new energy-efficient caching scheme that stores the most popular content at the edge of the core network and optimises the size of cached content to minimise energy usage. It takes into account the trend of daily traffic and recommends putting inactive segments of caches in sleep-mode during off-peak hours. Our results showed that power minimisation is achieved by deploying switch-off capable caches, and the trend of active cache segments over the time of day follows the trend of traffic. Second, the study explores different content popularity distributions and determines their influence on power consumption. The distribution of content popularity dictates the resultant cache hit ratio achieved by storing a certain number of videos. Therefore, it directly influences the power consumption of the cache. The evaluation results indicated that under video services where the popularity of content is very diverse, the optimum solution is to store the few most popular videos in caches. In contrast, when video popularities are similar, the most power efficient scheme is either to cache the whole library or to avoid caching completely depending on the size of the video library. Third, this thesis contributed an evaluation of the power consumption of the network under real world TV data and considering standard and high definition TV programmes. We proposed a cache replacement algorithm based on the predictable nature of TV viewings. The time-driven proactive cache replacement algorithm replaces cache contents several times a day to minimise power consumption. The algorithm achieves major power savings on top of the power reductions introduced by caching. CDNs are expected to continue to be the backbone for Internet video applications. This work has shown that storing the right amount of popular videos in core caches reduces from 42% to 72% of network power consumption considering a range of content popularity distributions. Maintaining up-to-date cache contents reduces up to 48% and 86% of power consumption considering fixed and sleep-mode capable caches, respectively. Reducing the energy consumption of CDNs provides a valuable contribution for future green video delivery

In silico identification of novel genetic factors associated with longevity in Drosophila

To determine genetic factors causing variation in survival into old age, several genome-wide association studies (GWAS) have been carried out on panels of long-lived individuals. The findings from a number of these GWAS studies were somewhat inconclusive, owing to the small sample sizes investigated. It is for this reason that model organisms such as Drosophila melanogaster have become increasingly important in identifying genetic factors underlying longevity. In this study we hypothesised that co-location of novel genes/genomic regions with genes, known to be associated with longevity, that share biological function with co-located genes, make them good candidates for novel genomic regions, linked to longevity. We further hypothesised that single nucleotide polymorphisms (SNPs) residing within these co-located regions may influence longevity either individually (when a SNP in one of these genes causes a particular phenotype) or collectively (when one or several SNPs in these regions occur in the same individual thus causing the phenotype). Summary statistics of datasets of SNPs generated by two GWAS (Burke et al., 2013; Ivanov et al., 2015) which include position of each SNP and a corresponding statistic (D or P- value) showing the strength of association with longevity were used in this study to guide the initial choice of genes/loci strongly associated with longevity. First, a network approach was applied to predict novel genes/genomic regions/SNPs, playing a role in longevity, which integrated three-dimensional (3D) chromosome conformation data (Hi-C) and two GWAS datasets. Networks were created using genes/genomic regions, known to associate with longevity, as original nodes with additional nodes (regions) later added to these networks if they strongly interacted (i.e. came into close proximity as measured by the Hi-C data) with the original nodes. Various network measures were calculated, in order to identify important previously unknown regions. These previously unknown regions were further explored and longevity associated genes were found including Rim and Tpi with a 'long-lived' phenotype, and some newly found regions were observed to be common between both GWAS datasets. A human ortholog search of genes found in this analysis resulted in matches to human genes with functions related to lifespan. Subnetworks of these GWAS-based networks were sought for enrichment in GO terms and several genes with no previous association with longevity but enriched in longevity-related terms were identified. Second, SNPs residing in non-coding regions, e.g. within transcription factor binding sites (TFBSs) recognised by transcription factors (TF) and borders between Topologically Associated Domains (TADs) were analysed. Each TF typically recognises a collection of often dissimilar DNA motifs. Here we hypothesised that TFs may recognise a certain structure, e.g. non-B DNA structures, rather than sequence motifs. Structures such as slipped, cruciform, triplexes and tetraplexes, formed on direct, inverted and mirrored repeats and G-quartets were considered and SNPs residing within these structures were analysed. For the study of SNPs in TAD borders we hypothesised that SNPs residing in these border regions may cause a severe disruption to the way in which regulation usually occurs within these TADs. We found that a significant proportion (~2%) of non-coding SNPs, reported in the DGRP GWAS dataset, resided in TAD border regions on the Drosophila genome, when compared to a match control dataset (

Transitions to animal domestication in Southeast Asia: Zooarchaeological analysis of Cồn Cổ Ngựa and Mán Bạc, Vietnam

The domestication of plants and animals was a pivotal process that significantly affected and shaped the trajectory of human history. However, this transition is still poorly understood in many parts of the world. For Mainland Southeast Asia (MSEA), most researchers believe this transition was initialised by a migration of agricultural groups that spread from the Yangtze into MSEA following rivers and the coastline (Bellwood and Oxenham 2008; Matsumura et al. 2008; 2011). This hypothesis posits that these migrant populations brought domesticated crops and animals into the region and lived alongside indigenous hunter-gatherer groups. This thesis analyses the transition from hunting and gathering to domestication by comparing the taphonomic and taxonomic characteristics of the faunal assemblages of Cồn Cổ Ngựa (CCN) and Mán Bạc (MB) in northern Vietnam. Both sites were selected as they sit on either side of the presumed hunter-gatherer (CCN) and agricultural (MB) subsistence transition in Vietnam and have the potential to show crucial societal changes. Since CCN and MB are burial sites, human-animal interactions at the sites have the potential to portray the belief systems and ontology of the people. The ultimate aim was to contextualise CCN and MB within the framework of subsistence change in Southeast Asia (SEA) and determine how and whether human behaviour and human-animal relationships developed during this purported transitional phase in the Mid Holocene. A clear and perceivable shift in the faunal composition between CCN and MB was found, and this transition can be confidently attributed to the introduction of domesticated animals around 4,000 cal. BP to northern Vietnam. Further, results from the principal component analysis of sites throughout SEA showed that the relative proportions of certain taxa can be useful in separating hunter-gatherer and agricultural based sites across the region, as well as revealing outliers based on localised environments and/or choice. It was emphasised that this transition from ‘hunting to farming’ was by no means clear-cut. MB still had a strong emphasis on hunting wild taxa and fishing, and these permeable cultural-economic boundaries are also perceivable in other SEA sites. However, this thesis suggests that domestic and wild animals probably imbued different meanings and significance. Further, both CCN and MB were not ‘simply middens’ reflecting what people ate, rather they pose intriguing insights into human-animal interactions. At both sites there is a perceivable change in the engagement with animals and the landscape that, this thesis argues, involved a reconceptualising of this relationship

Design of Ancillary Services for Battery Energy Storage Systems to Mitigate Voltage Unbalance in Power Distribution Networks

power system, voltage unbalance issues are expected to exacerbate. Single{phase connectedphotovoltaic (PV) panels may cause unequal three{phase power ows, resultingin unbalanced grid currents and voltages. In addition, the random charging behaviour ofPlug{in Hybrid Electric Vehicles (PHEVs) equipped with single{phase on{board chargersis expected to further contribute to voltage unbalance rise as the number of thesedevices grows. If voltage unbalance increases to unacceptable levels, it may have adverseeects on power system operation and on the equipment connected to it. Traditionally,the phase swapping technique has been deployed by distribution system operators forvoltage unbalance mitigation, while other mitigating techniques include the deploymentof power electronics-based devices. The majority of the devices reported in the literatureare based on three-phase congurations, including series and parallel active power lters,unied power quality conditioners (UPQCs), static synchronous compensators (STATCOMs)and, more recently, three-phase distributed generation (DG) inverters.This research proposes the use of single-phase battery energy storage systems (BESSs)for the provision of phase balancing services, which has been considered only in a few literatureworks, with most of these research papers focusing on three-phase BESSs. In thisthesis, a novel control strategy is proposed for single-phase BESS units to compensatevoltage unbalance by injecting both active and reactive power simultaneously. The proposedapproach is based on the coordinated operation of three independent single-phaseBESS inverters using local voltage and current measurements.Initially, a comprehensive literature review is performed with the following aims: arobust classication of the ancillary services currently oered by BESSs, harmonisation ofthe notation found in the literature for ancillary services, and identication of potentialfuture applications of BESSs to power grids with large number of Low Carbon Technologies(LCTs). Then, the eectiveness of the proposed voltage unbalance compensationmethod is validated in the simulation environment, where two realistic models of distributionsystems are developed. Next, the impact of increasing PV and EV penetrationlevels on voltage unbalance for a typical UK distribution system is assessed based on adeterministic approach. The control strategy is validated experimentally by carrying outHardware-In-The-Loop (HIL) tests. Finally, an equivalent model of the distribution systemand BESS inverter is derived, which allows to carry out a preliminary probabilisticstudy to cater for the uncertainties related to the location and size of the PVs and EVs,and to evaluate the voltage unbalance levels without and with the BESSs controlled toprovide voltage unbalance compensation.It is concluded that the proposed BESS control system may eectively reduce thevoltage unbalance levels under various loading and generating conditions