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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
551

Diet and death in times of war: isotopic and osteological analysis of mummified human remains from southern Mongolia

Turner, B.L., Zuckerman, M.K., Garofalo, E.M., Wilson, Andrew S., Kamenov, G.D., Hunt, D.R., Amgalantugs, T., Frohlich, B. 10 1900 (has links)
No / This study presents the results of an isotopic analysis of nine naturally mummified individuals—three adults, two adolescents, one juvenile, and three infants—recovered from the Hets Mountain Cave site in southern Mongolia, where they had been secondarily deposited. All of the individuals show evidence of violent perimortem trauma, but no skeletal indicators of nutritional or disease-related stress. Multi-isotopic data (δ13C, δ15N, δ18O, 87Sr/86Sr, and 20nPb/204Pb) were characterized in multiple tissues from each individual when possible, in order to reconstruct diet composition and residential origin at different points in life. Specifically, δ13C and δ15N in bone carbonate and collagen (N = 8) and hair keratin (N = 4) were coupled with enamel carbonate δ18O and δ13C (N = 3) and enamel 87Sr/86Sr, and 20nPb/204Pb (N = 3) to assess diet and residential mobility in relation to skeletal indicators of health and trauma. Results are consistent with a persistence of mixed C3/C4 pastoral subsistence and general stability of diet composition over the life course, in contrast to contemporary accounts of widespread famine and a dependence on grains imported from China throughout the region. However, results also suggest that at least some individuals may have migrated to this region of southern Mongolia from elsewhere during life, meaning that their dietary isotopic profiles may not represent local subsistence patterns near the Hets Mountain Cave site. Overall, these results speak to the utility of life course oriented multi-isotopic analysis in complementing more top-down historical analyses in understanding variation in subsistence, nutrition, and migration in regions undergoing significant political and economic turmoil.
552

Chemistry and Transport of Metals from Entrenched Biosolids at a Reclaimed Mineral Sands Mining Site in Dinwiddie County, Virginia

Lasley, Katrina 04 August 2008 (has links)
Deep row incorporation of biosolids is an alternative land application method that may allow higher than currently permitted mine land reclamation application rates. Biosolids treated by various processes possess characteristics that uniquely affect metal solubility and mobility due to their influence on metal speciation. The objectives of this research were to compare the effects of biosolids stabilization type and rate on heavy metal solubility, mobility, and speciation. Two rates each of Alexandria, (Virginia) anaerobically digested (213 and 426 dry Mg ha-1) and Blue Plains (Washington, DC) lime-stabilized (329 and 657 dry Mg ha-1) biosolids were placed in trenches at a mineral sands mine reclamation site in Dinwiddie County, Virginia in June and July 2006. Vertical and lateral transport of heavy metals from the biosolids seams were determined by analyzing leachate collected in zero tension lysimeters below the trenches and suction lysimeters adjacent to the trenches. Chloride (Cl-), sulfate (SO42-), nitrate (NO3-), phosphate (PO43-), dissolved organic carbon (DOC), and pH were also determined within the dissolved fractions (< 0.45 µm) collected on September 8, 2006, November 3, 2006, January 5, 2007, June 8, 2007, and September 7, 2007 as input for the speciation program MINTEQA2. Silver, Cd, Pb, and Sn did not move vertically or laterally to any significant extent. Lime-stabilized biosolids produced higher cumulative metal mass transport per sampling period for Cu (967 g ha-1), Ni (171 g ha-1), and Zn (1027 g ha-1) than the anaerobically digested biosolids and control during the 15-month period following entrenching. Barium mass loss was similar for both biosolids. All metals moved primarily with particulates. MINTEQA2 predicted the majority of the metals within the dissolved fraction were present as free ions. As pH decreased and time increased, the amount of association with fulvic acids decreased allowing more free ions and binding with inorganic ligands. Little movement into groundwater demonstrates that anaerobically digested and lime-stabilized biosolids can be land-applied at high rates with little concern of heavy metal contamination of groundwater under these conditions. / Master of Science
553

A Network Mobility Survey and Comparison with a Mobile IP Multiple Home Address Extension

Wells, John Dowling 11 February 2004 (has links)
This thesis addresses the paucity of research on network mobility with a taxonomy and a quantitative comparison on a real test bed of existing and forthcoming network mobility solutions. Broadly, network mobility solutions can be divided into two broad categories, intra-domain and inter-domain solutions. The two are distinct enough to warrant separate solutions. Network mobility solutions can also be divided into four catogories according to their implementation, (i) Mobile IP-based solutions, (ii) Mobile IP Mobile Routing, (iii) intra-domain routing protocols, and (iv) Mobile IP Foreign Agent-based solutions. This latter division by implementation serves as a useful starting point for a discussion and study of these protocols. The qualitative and quantitive comparisons presented here yield two "winning" solutions, Mobile IP with Network Address Translation (NAT) and Mobile IP Mobile Routing, both based on Mobile IP, the draft standard for Internet mobility. The two were chosen because they are the only solutions fit for production networks, not necessarily because they are the best performing solutions. Indeed, nearly all of the other solutions are promising alternatives and some, such as mobile ad hoc network (MANET) routing protocols and the solutions based on the next generation Internet (IPv6) version of Mobile IP, are particularly so. One of the solutions uses a novel extension for Mobile IP, the Multiple Home Address extension, developed and specified in this thesis, that turns a Mobile IP mobile node into a mobile router able to support dynamically sizing mobile networks while using the existing Mobile IP infrastructure. / Master of Science
554

Mobility management incorporating fuzzy logic for a heterogeneous IP environment

Chan, Pauline M.L., Sheriff, Ray E., Hu, Yim Fun, Conforto, P., Tocci, C. January 2001 (has links)
Yes / The next generation in mobility management will enable different mobile networks to interoperate with each other to ensure terminal and personal mobility and global portability of network services. However, in order to ensure global mobility, the deployment and integration of both satellite and terrestrial components are necessary. This article is focused on issues reltaed to mobility management in a future mobile communications system, in a scenario where a multisegment access network is integrated into an IP core network by exploiting the principles of Mobile IP. In particular, attention is given to the requirements for location, address, and handover management. In a heterogeneous environment, the need to perform handover between access networks imposes particular constraints on the type of information available to the terminal and network. In this case, consideration will need to be given to parameters other than radio characteristics, such as achievable quality of service and user preference. this article proposes a new approach to handover management by applying the fuzzy logic concept to a heterogeneous environment. The article concludes with the presentation of mobility management signaling protocols.
555

Experiences of Academics from a Working-Class Heritage: Ghosts of Childhood Habitus

Binns, Carole 03 September 2019 (has links)
No / Higher education is welcoming students from diverse educational, social, and economic backgrounds, and yet it predominantly employs middle-class academics. Conceptually, there appears, on at least these grounds alone, to be a cultural and class mismatch. This work discusses empirical interviews with tenured academics from a working-class heritage employed in one UK university. Interviewees talk candidly about their childhood backgrounds, their school experiences, and what happened to them after leaving compulsory education. They also reveal their experiences of university, both as students and academics from their early careers to the present day. This book will be of interest to an international audience that includes new and aspiring academics who come from a working-class background themselves. The multifaceted findings will also be relevant to established academics and students of sociology, education studies and social class.
556

Urban Spatiotemporal Energy Flux

Mohammadi, Neda 30 November 2016 (has links)
Urban energy systems are often studied in a very similar way in the sense that the characteristics of the underlying physical infrastructure are weighted as the main determinants of energy use predictions, while the behavior of the human population in relation to this systemthe so-called ``energy consumers''in time and urban spaces is effectively neglected. The spatial and temporal variations in infrastructure-population interactivity greatly complicate urban energy systems; the unremitting growth in population and advances in technology mean that the dynamic interrelationship between the population and urban environment will continue to grow exponentially, resulting in increasing uncertainties, unreliable predictions and poor management decisions given the inadequacy of existing approaches. In this dissertation, I explore the interdependencies of spatiotemporal fluctuations of human mobility as an indicator for human activities and energy use in urban areas in three main studies. First, I show that the fluctuations of intra-urban human mobility and energy use have an underlying structure across both time and space, and that human mobility can indeed be used as a predictor for energy use in both dimensions. Second, I examine how one of the dominant drivers of this structure, namely individuals' location-based activities, influence patterns in energy supply and demand across building types (i.e. residential and commercial buildings) and show how variations in the human mobility networks of two distinct urban populations (the so-called returners and explorers) can explain fluctuations in energy use. Third, I introduce an integrated approach for predicting urban energy use across time and space by incorporating these interdependencies. Generating predictive models that capture the spatiotemporal variations in these determinants in urban settings, as suggested in this research, will contribute to our understanding of how variations in urban population activities for particular times and locations influence can be applied to estimate energy use patterns in surrounding areas. / PHD / Today’s cities are the most complex built environments in human history, containing 54% of the world population and responsible for up to 80% of the world’s total energy consumption. As a result of population growth and advances in technology, the interdependencies between infrastructure, services, and individuals in urban spaces continue to increase, presaging an ambiguous future with challenges we are not yet aware of. In this research, I developed the concept of <i>urban spatiotemporal flux</i> to study the interdependencies between energy use and human activities using human mobility at various spatial and temporal scales to address the urgent need to incorporate the resulting fluctuations in energy use into future energy predictions. Intra-city human activities change more rapidly and exhibit higher levels of dynamic characteristics than the simple physical locations identified in current master plans. Previous research has tended to focus on predicting energy consumption at different spatial levels as a function of the physical characteristics of buildings or cities, often relying on sensor-based data-driven approaches. There has been some effort to explore the predictability of human mobility by building human mobility-based predictive models across applications such as traffic and travel demand predictions, human activity predictions, next place locations, epidemics and the spread of viruses, and air pollution. The two perspectives are rarely in conversation with each other, however, with only minimal integration of our understanding and predictions for different urban spatial and temporal scales. The technology that has become an integral part of everyday life in today’s smarter urban environments now allows us to use human beings as “sensors” that provide useful data for predictions of energy use. Using tens of millions of yearly individual positional records across thousands of spatial divisions, along with millions of corresponding measures of energy use from energy meters in Greater London and the City of Chicago, I discovered that fluctuations in urban energy consumption are likely governed by the structure of human mobility networks and are dominated by certain populations and buildings types, among other factors. Intra-urban human mobility and energy use are not spatially randomly distributed across urban settings; instead, there is an underlying structure that explains their dependency. Temporal manifestations of these fluctuations suggest a continuous spatiotemporal relationship between human mobility and energy use, which confirms that the values observed in one location depend to some extent on what is happening at adjacent locations at around the same time. This dependency represents a strong connection with the returner populations’ mobility and residential buildings’ energy use and there is an associated spatial spillover effect. Future energy efficiency strategies should thus reflect these spatiotemporal dependencies, enabling planners to create new and more effective ways for both different building types and the mobility networks of the urban population to play major roles in energy related strategies, as well as helping to identify the fluctuating determinants that represent additional evidence of a spatiotemporal structure.
557

Enterprise Mobility : Defining and evaluating business digitalization

Arlestedt, Rebecka, Lindh, Melenie January 2016 (has links)
Mobile technology has developed rapidly in the recent years and considerably changed the way organizations work. Mobility can bring great benefits to the organizations of which they are at, by e.g. improving employee satisfaction and increase efficiency and productivity. Despite this the development of mobile solutions have grown much faster for individuals than for organizations, with a plethora of devices and applications. The slow enterprise adoption is partly due to the fact that companies need to take information security risks into account at the same time as IT systems need to be rebuilt and customized to accommodate the new mobile way of working. Employees, unlike most other technologies, largely drive mobile strategies at organizations. Organizations are not developing in a fast enough pace and many scientist are describing a research gap in organizations adoption of mobility. This study aims to examine how research in the area has been presented and how enterprise mobility is viewed and utilized. The study has been implemented through qualitative research with a interpretative and exploratory approach. A case study was conducted at two organizations, demonstrating the possibilities and obstacles of enterprise mobility, and also strengthened the existing definition of the field. Additionally the case study illustrated discrepancies in IT solutions and the adoption of enterprise mobility within two different industries. Both researchers and organizations have shown a great interest in exploring this area additionally. Further studies can be extended to include the effects of how companies have adapted to enterprise mobility. / Den mobila teknologin har utvecklats i snabb takt under de senaste åren och således förändrat organisationers sätt att arbeta. Mobilitet kan möjliggöra för organisationer att t.ex. förbättra de anställdas tillfredsställelse, öka effektiviteten och produktiviteten, samt minimera kostnader. Trots den snabba utveckling av såväl mobila lösningar som mobila enheter, så har utvecklingen gått betydligt snabbare för privatpersoner än för organisationer. Detta kan delvis förklaras av det faktum att organisationer, i större utsträckning än privatpersoner, måste ta hänsyn till de säkerhetsrisker som mobilt arbete kan medföra. Det kan också förklaras av att många IT-system kräver vidareutveckling och anpassning för att kunna möta det nya mobila sättet att arbeta. Att organisationer inte utvecklas i tillräcklig snabb takt ligger till grund för att många forskare beskriver att det finns ett forskningsgap i organisationers antagande av mobilitet. Denna studie syftar därför till att undersöka hur begreppet enterprise mobility presenteras i tidigare forskning samt hur det uppfattas och tillämpas bland anställda. Studien har använt en kvalitativ forskningsansats med ett undersökande och tolkande förhållningssätt. En fallstudie har genomförts på två olika organisationer för att identifiera möjligheter och utmaningar med enterprise mobility, men också för att stärka den befintliga definitionen av begreppet. Fallstudien presenterar också skillnader i anpassade IT-lösningar och antagandet av mobilitet inom två olika branscher. Både forskare och organisationer har uttryckt ett stort intresse av att utforska detta område ytterligare. Denna studie ligger till grund för att senare undersöka effekterna av hur företagen har anpassat sig till enterprise mobility.
558

E-mobility - gå mot strömmen : En studie om elbilen som fenomen och dess förutsättningar i framtiden.

Blom, Hedvig, Lopar, Nikolina January 2015 (has links)
Syfte &amp; forskningsfråga: Syftet med den här uppsatsen är att utreda och analysera hur olika faktorer kan påverka efterfrågan och försäljning av elbilen. Syftet är också att identifiera förutsättningar för elbilens framtid och betydelse inom bilsektorn. Uppsatsens forskningsfråga formulerades utifrån uppsatsens syfte och frågan är följande: Vad krävs för att elbilen ska nå ut till en bredare målgrupp i framtiden? Metod: Vår uppsats är baserad på en kvalitativ forskningsmetod för att vi ska få en djupare förståelse kring det valda forskningsområdet. Vi har strävat efter en induktiv ansats i studien men vi är medvetna om att vi har deduktiva inslag, vilket har bidragit till att uppsatsen har en abduktiv karaktär. Vi valde att ta med respondenter med olika positioner från både bilföretag, bilmagasin samt en intresseorganisation för att få en mer bredare syn på forskningsområdet. Sammanlagt har vi sju respondenter samt två fokusgrupper som har bidragit med information till det empiriska materialet i uppsatsen. Slutsatser: I vårt avslutande kapitel besvarar vi våra delsyften som vi har i studien samt vår forskningsfråga om vad som krävs för att elbilen ska nå ut till en bredare marknad i framtiden. Vi anser att elbilen har goda förutsättningar till att utvecklas ännu mer samt spridas till fler kundsegment. Vi har genom vår teoretiska och empiriska analys identifierat att statliga incitament och förmåner, en ökad medvetenhet bland kunderna samt en sänkning av priset är de främsta faktorerna som kan bidra till en utökning av elbilen på marknaden.
559

Labour migration and economic development in Guangdong, China: implications for labour mobility

徐宗玲, Xu, Zhongling. January 1997 (has links)
published_or_final_version / Asian Studies / Doctoral / Doctor of Philosophy
560

Exploring gas-phase protein conformations by ion mobility-mass spectrometry

Faull, Peter Allen January 2009 (has links)
Analysis and characterisation of biomolecules using mass spectrometry has advanced over the past decade due to improvements in instrument design and capability; relevant use of complementary techniques; and available experimental and in silico data for comparison with cutting-edge research. This thesis presents ion mobility data, collected on an in-house modified QToF mass spectrometer (the MoQTOF), for a number of protein systems. Two haemoproteins, cytochrome c and haemoglobin, have been characterised and rotationally-averaged collision cross-sections for a number of multimeric species are presented. Intact multiply-charged multimers of the form [xCyt c + nH]z+ where x = 1 (monomer), x = 2 (dimer) and x = 3 (trimer) for cytochrome c have been elucidated and for species with x ≥ 2, reported for the first time. Fragment ions possibly attributed to a novel fragmentation mechanism, native electron capture dissociation, are reported with a brief discussion into their possible production from the dissociation of the gas-phase dimer species. Haemoglobin monomer globin subunits, dimers and intact tetramer have been successfully transferred to the gas phase, and their cross-sections elucidated. Comparisons with in silico computational data have been made and a discussion of the biologically-active tetramer association/dissociation technique is presented. Three further proteins have been studied and their gas-phase collision cross-sections calculated. Two regions of the large Factor H (fH) complement glycoprotein, fH 10-15 and fH 19-20, have been characterised for the first time by ion mobility-mass spectrometry. Much work using nuclear magnetic resonance spectroscopy has previously been achieved to produce structural information of these protein regions, however further biophysical characterisation using mass spectrometry may aid in greater understanding of the interactions these two specific regions have with other biomolecules. The DNA-binding core domain of the tumour suppressor p53 has been characterised and cross-sections produced in the presence and absence of the zinc metal ion that may control the domain’s biological activity. Within this core domain, p53 inactivation mutations have been shown to occur in up to 50% of human cancers, therefore the potential exists to further cancer-fighting activity through research on this region. Anterior Gradient-2 (AGR2) protein facilitates downregulation of p53 in an as yet unclear mechanism. Recent work using peptide aptamers has demonstrated that this downregulation can be disrupted and levels of p53 restored. Collision cross-sections for six peptide aptamers have been calculated, as well as cross-sections for multimers of AGR2 protein. A complex between one aptamer with the protein has also been elucidated. Use of the commercially available Synapt HDMS ion mobility-mass spectrometer at Waters MS Technologies Centre (Manchester, UK) allowed data to be collected for both Factor H protein regions and for the DNA-binding core domain of p53. Data are compared in the appropriate chapters with data collected using the MoQTOF.

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