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外文学位

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  • [学位] Evaluation of the strength and elastic properties of cement stabilised materials

    The thesis presents details of tests carried out to determine the strength and elastic properties of cement stabilised materials, emphasis being placed on their behaviour in uni-axial tension under quasi-static loading. The materials tested are lean concrete, a typical cement bound granular material, a fine grained soil-cement and two synthetic cement bound granular materials produced by combining gravel and sand with the fine grained soil. A limited investigation of behaviour under repeated loading in uni-axial tension was also undertaken. The principal conclusions, relating to specimens compacted to refusal, are that the strength in uni-axial tension is broadly related to the strength in uni-axial compression, the moduli of elasticity in tension and in compression are essentially equal, the stress-strain relationship in tension is effectively linear, and that whilst strength may be related to modulus for each material, there is no unique relationship between these critical parameters.

  • [学位] Complex Effects of Telecouplings on a Coupled Human and Natural System

    Rural areas around the world are increasingly exposed to the effects of telecouplings (socioeconomic and environmental interactions over distances), often with profound implications for sustainability. To support economic growth that is ecologically sound, there is an urgent need for improved understanding of the complex effects of telecouplings on rural areas.;This dissertation presents investigations of the complex effects of telecouplings on an exemplary rural coupled human and natural system (CHANS) -- Wolong Nature Reserve (Wolong) in China. Wolong is connected to the outside world through telecouplings, such as payments for ecosystem services (PES) programs [e.g., the Grain-to-Green Program (GTGP) and the Grain-to-Bamboo Program (GTBP)], nature-based tourism, and labor migration. Specific objectives of this dissertation were to: (1) reveal the pathways through which telecouplings affect socioeconomic outcomes; (2) uncover the spillover, feedback, and interaction effects of telecouplings; and (3) assess interrelated changes in livelihoods and human well-being after the sudden changes of telecouplings caused by a natural disaster.;Using the GTGP and the GTBP implemented in Wolong as examples, we showed that telecouplings shaped interrelated livelihood activities and formed complex pathways affecting socioeconomic outcome (Chapter 2). By elucidating the underlying pathways, we identified specific reasons for the unexpected negative impacts of the GTGP and the GTBP on household income. We also found that the impacts of telecouplings spilled over to nontargeted areas and generated unintended consequences (Chapter 3). In addition to the lost revenue from cropland enrolled in the GTGP, the GTGP intensified crop damage on remaining cropland, leading to a hidden cost that is often ignored in the design of PES programs' compensation scheme. As the impacts of telecouplings on the focal CHANS accumulated, feedback occurred (Chapter 4). Our results showed that the crop damage on remaining cropland caused by the GTGP increased the willingness of local households to enroll it in future GTGP, which triggered a positive feedback that will strengthen the influences of GTGP in Wolong and beyond. Different telecouplings interacted with each other and generated unexpected impacts on environmental outcomes (Chapter 5). Our systems modeling results show that the interaction between the telecouplings of nature-based tourism and labor migration weakened their total effect on forest recovery. Evolution of telecouplings in Wolong was interrupted by a natural disaster, generating profound impacts on post-disaster recovery outcome (Chapter 6). Our analyses show that livelihoods in Wolong experienced substantial changes in response to the changes in telecouplings after the 2008 Wenchuan Earthquake. However, most of these livelihood changes negatively affected, instead of facilitating, human well-being recovery.;This interdisciplinary study provided a solid example showing how the complex effects of telecouplings on a CHANS can be studied by integrating approaches from different disciplines. Findings and methods from this dissertation provide essential information and tools for understanding, predicting, and managing telecouplings to achieve Sustainable Development Goals in an increasingly telecoupled world.

  • [学位] Training needs analysis for engineering technicians in Oman

    This thesis examines the transition from the Omani Colleges of Technology (CT) to employment of its engineering graduates. It arises out of concerns that the transition to the labour market for engineering graduate is problematical. The research was carried out to identify the knowledge, skills, and abilities (KSA) of engineering technicians required in the Omani market place. The aim is to provide local curriculum designers in the Colleges of Technology with sufficient information about the required KSA in order to create and enhance the engineering curriculum so that it has greater capacity to meet the needs of a variety of stakeholders and of employers in particular. This in turn has the potential to bridge the gap between what is presently taught and what the workplace demands. Personnel psychologists identify views concerning the skills that are required for different jobs. One of these is based on the assumption that quite different skills are required in different jobs (SCANS, 1990). This view generates approaches within job analysis: the worker-oriented and the task-oriented approaches. This research uses Position Analysis Questionnaire (PAQ), which is a worker-oriented job analysis instrument, to investigate the KSA required to perform some of the engineering technician jobs in Omani industries. In addition, semi-structured interviews were used to investigate the factors that either hinder or entirely prevent the new graduates from Colleges of Technology from being accepted in the workforce pool. The major research findings concern the dimensions of knowledge, skills, and abilities of six engineering technician job titles and the major factors that hinder or (prevent) the technical college graduates from being accepted in the market place in Oman. These findings would definitely help design better transition route and bridge the gap between the CT technicians engineering programmes and the workplace demands.

  • [学位] Inhibitory Effects of Sulfonylureas and Non-Steroidal Anti-Inflammatory Drugs on In-Vitro Metabolism of Canagliflozin in Human Liver Microsomes

    Canagliflozin, a sodium-glucose transport protein 2 (SGLT2) inhibitor, is a novel drug used to treat type 2 diabetes mellitus (T2DM). A phase II glucuronide conjugation reaction is the primary elimination pathway of canagliflozin. Uridine diphosphate glucuronosyltransferases (UGTs) are the responsible enzymes for the glucuronidation reactions that occur in phase II metabolism. The glucuronidation of canagliflozin results in formation of two major inactive metabolites, M7 and M5 that are catalyzed by UGT1A9 and UGT2B4, respectively. Canagliflozin is commonly co-administered with other antidiabetic agents such as sulfonylureas. Until now, there is no documented in vitro drug-drug interactions (DDIs) study conducted to assess the inhibitory effect of other drugs on the metabolism of canagliflozin. Moreover, the inhibitory effects of sulfonylureas against UGTs isoenzymes are not well established. In this study, the inhibitory effect on the metabolism of the two metabolites of canagliflozin, M7, and M5 has been investigated using three sulfonylurea drugs as inhibitors, including chlorpropamide, glimepiride, and gliclazide. Additionally, two non-steroidal anti-inflammatory drugs were included as positive controls which are known for their inhibitory effect against UGT1A9 (niflumic acid) and UGT2B4 (diclofenac). The formation rate of M7 and M5 metabolites were monitored by HPLC after incubation of canagliflozin as a substrate with and without inhibitors at different concentrations. The IC50 values were calculated for all inhibitors by using five different individual human liver microsomes (HLMs) including pooled HLMs. Ki values were calculated for niflumic acid by using additional three individual HLMs and a pooled sample. Among sulfonylureas, glimepiride showed the most potent inhibitory effect against M7 metabolite formation with an IC50 value of 88 +/- 4 microM, compared to chlorpropamide and gliclazide with IC50 values of more than 500microM. Diclofenac inhibited M5 metabolite formation, which is catalyzed by UGT2B4, more than M7, with IC50 values of 32 +/- 13microM for M5 and 80 +/- 13 microM for M7. Niflumic acid showed no inhibition activity against M5 formation, but showed relatively selective inhibitory potency against M7 formation with an IC50 value of 1.9 +/- 0.03microM and a Ki value of 0.8+/-0.25 microM. The results of this study suggest that there may not be a metabolic interaction between canagliflozin and sulfonylureas. This study also demonstrates a possible clinical interaction between niflumic acid and canagliflozin. The low Ki value of niflumic acid, when compared to its maximum plasma therapeutic concentration, suggest the possibility of a clinical drug interaction which could be of therapeutic impotence.

  • [学位] Understanding the Marketing and Management of Trails Using Pestel Analysis

    Trails are an important resource for local communities because they provide health, social, economical, and environmental benefits ("Headwaters Economics", 2016). When trails are made accessible in towns, it facilitates communal connection, draws in tourists, increases support for conservation lands, and creates safer trails. Trails are valuable to towns because they are an integral piece of their livelihood, therefore the management of trails should be researched to understand how to sustain public use. For this study, twelve (N = 12) conservation commissioners, town managers, and other trail stakeholders from two counties in a Northeastern state were interviewed about how they manage their trails. Results of the study were analyzed and coded, utilizing a marketing theory called PESTEL. Six PESTEL categories were used to interpret stakeholder comments on how trails are managed. The findings of the research show how managing and marketing trails to promote access and use could potentially maximize trail benefits for town communities.

  • [学位] Effects of Job Stereotype, Applicant Gender, and Powerful and Powerless Speech Styles on Telephone Interview Outcomes

    By examining the effects of powerful and powerless speech styles, gender stereotyped jobs, and gendered voices during the employment interviewing process, this study sought to further the research of Parton (1996); Parton, Siltanen, Hosman, and Langenderfer (2002); and Juodvalkis, Grefe, Hogue, Svyantek, and DeLamarter (2003). This study was designed to further explore the possibility of longitudinal changes within acceptable communicative expectations during telephone job interviewing. Participants (undergraduate and professional) listened to two audio taped interviews manipulated by speech style, stereotyped job title, and interviewee gender. Variables were evaluated on semantic differential scales following the previous work of Parton (1996). Similar to those of Parton (1996) and Parton et al. (2002), results indicated that powerful speech style suggested positive attributions of overall impression and employability; and gender significantly interacts with speech style and attribution of similarity and within several multiple variable interactions. Results further indicated that undergraduate and professional participants continue to evaluate speech styles differently. However, the current study found significance for control-of-self within multi-variated interactions that were previously not found. Therefore, theoretical outcomes and implications within the associated research were addressed.

  • [学位] A Contour Based Face Recognition Method Using Facial Symmetry Features

    Human face recognition is a complex problem in computer vision and accuracy of an algorithm for face recognition depends on a lot of factors such as quality of input image, the accuracy of the algorithm, time complexity, space complexity, quality of training data, the accuracy of training algorithm etc. In our proposed process of face recognition, we use a much simpler approach that not only produces equally efficient output in low-quality and high-quality input images but also follows a simple image matching approach using facial symmetry features. First, we used Viola and Jones algorithm described in Viola & Jones (2004), to detect the face boundary which gives us some horizontal facial features such as ear line in both left and right side of the image and vertical facial features such as the top of the forehead and bottom of the chin. The rest of the features are extracted from the position of eye, nose and mouth. To detect the position of mouth, nose, and eye we devised an efficient algorithm that is capable of producing output with RGB, grayscale and B/W input image which makes this approach robust and portable. After detecting these facial land points, we calculate horizontal and vertical symmetry features. These symmetry features are extracted from both the reference and sample image and forwarded to our matching algorithm which gives us the percentage of similarity between two images.

  • [学位] High Performance On-Demand Video Transcoding Using Cloud Services

    Video streams usually have to be transcoded to match the characteristics of viewers' devices. Transcoding is a computationally expensive and time-consuming task. Streaming service providers have to store numerous transcoded versions of a given video to serve various display devices, which becomes cost-prohibitive while the video streaming demands increase significantly. Given the fact that viewers' access pattern to video streams follows a long tail distribution, we propose to transcode video streams with low access rate in an on-demand manner using cloud computing services. The challenge in utilizing cloud services for on-demand video transcoding is to maintain a robust QoS for viewers and cost-efficiency for streaming service providers. To address this challenge, in this dissertation, we present a Cloud-based Video Streaming Service (CVSS) architecture which includes a QoS-aware scheduling method to efficiently map video streams to cloud resources. With a detailed study and anlysis of the performance affinity of the transcoding operations on different types of Virtual Machines (VMs), we proposed self-configurable VM provisioning policies to transcode video in a more cost-efficient way. Simulation results demonstrate that with the policies, CVSS architecture maintains a robust QoS for viewers while reducing the incurred cost of the streaming service provider by up to 85%. This dissertation also presents a Cloud-based Video Live Streaming (VLSC) architecture that facilitates transcoding for live video streaming while considering QoS.

  • [学位] Anxiety in William Gibson's "Blue Ant" Trilogy: The Construction of Space, Time, and Community in the Post-Cyberpunk Literary Environment

    William Gibson is well known for his science fiction writing within the cyberpunk literary genre, which often evoke themes of economic disparity, environmental desolation, and the breakdown of the contracts between state and populace allowing corporate power to emerge dominant. In his most recent series of novels, commonly dubbed the Blue Ant trilogy, Gibson focuses on themes of national decay compounded by the real-time emergence of post-national corporate power that degrades or usurps control over borders, identities, and infrastructures.;My intent is to examine how Gibson's writing attempts to address the issue of the rise of post-national corporate power by singling out instances of anxiety in the white Western discursive sphere, and how Gibson's Blue Ant trilogy has difficulty addressing this anxiety due to a historically constituted, culturally imposed barrier that prevents both the narrative and the characters inside it from being able to articulate them. This essay further attempts to explore this barrier, best understood as a reinforcement of white, Western cultural hegemony, can be deconstructed and understood as a subjective position as opposed to a universal, and moved beyond it.

  • [学位] Plants and the Monongahela people: An archaeobotanical analysis of the Johnston Site (36IN2)

    Archaeobotanical research allows archaeologists to understand what plant resources people in the past were consuming and utilizing in addition to how those resources were organized spatially within a site. Investigations at the Johnston Site, a Monongahela village in Western Pennsylvania, date back to the 1950s, yet analysis is not complete in regards to archaeobotanical samples. This thesis focuses on an analysis of the carbonized botanical material retrieved through flotation in order to understand what resources the Monongahela people used, the distribution of resources across features, and what may be learned about the people living in the village. While some patterns are beginning to present in regard to species distribution between domestic and communal areas, and the potential for social complexity to be found in these difference, these results are just the beginning of what could be learned about the people of the Johnston Site.

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