571 research outputs found

    Life-cycle cost-benefit analysis of green roofing systems: the economic and environmental impact of installing green roofs on all atlanta public schools

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    This study examines the relationship between environmental sustainability and green schools, seeking to highlight the benefits and determine the Net Present Value (NPV) installing vegetative roofs on all schools in the Atlanta Public Schools District. This study quantifies the costs and benefits of thin-layer, or extensive, green roof systems as they compare to typical flat roofs on Atlanta Public Schools. Quantifiable benefits are detailed and suggestions are made to create the means by which other social benefits may be quantified. The purpose of this thesis is to establish proof to the Atlanta Public Schools District that over a 40 year period there are more benefits associated with installing vegetative roofs on all of their flat roofs than there are costs. While some may argue that greens roof are more costly than traditional roof systems, this study provides evidence that the cumulative benefits over a 40 year life cycle associated with large scale green roof installations, such as on all Atlanta Public Schools, are greater than the initial costs incurred. Factors included in the analysis of benefits were reductions to energy/utility costs, reduced emissions, and avoided best management practices (BMPs). Other considerations include social benefits resulting from the mitigation of storm water runoff, reductions to the urban heat island, productivity level increases (students and teachers), and avoided regulatory fees.M.S.Committee Chair: Ashuri, Baabak; Committee Member: Roper, Kath

    Socio-econmonic Stratification, Disorganized Volunteerism, and the Key to Multicultural Diversity

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    The presentation will ask the participants to examine the impediments of organized volunteerism in terms of accomplishing the goals of multicultural diversity. Keywords: Diversity, Multiculturalism, Socio-Economic stratification, friendship, organized volunteerism, disorganized volunteerism, charit

    Study Abroad for Low-income Students: The Relationship Between Need-based Grant Aid and Access to Education Abroad

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    This study explores factors related to low-income students’ decisions to participate in study abroad while focusing specifically on the role of need-based grant aid in this decision-making process. Estimates account for systematic differences between students receiving and not receiving need-based grant aid using propensity score modeling (PSM) before disaggregating models by need-based grant aid status. Results indicate that need-based grant aid significantly increases a student’s probability of participating in study abroad. Additionally, disaggregated models show that the study abroad decisions of students receiving need-based grant aid differ significantly from those not receiving this aid, particularly when considering other forms of financial aid, such as loan debt. Specifically, low-income students appear to take on additional loan debt to access study abroad when they do not receive need-based grant aid. These findings have important implications for policy and practice that is focused on increasing access to study abroad to a diverse U.S. student population

    Atomic oxygen effects on boron nitride and silicon nitride: A comparison of ground based and space flight data

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    The effects of atomic oxygen on boron nitride (BN) and silicon nitride (Si3N4) were evaluated in a low Earth orbit (LEO) flight experiment and in a ground based simulation facility. In both the inflight and ground based experiments, these materials were coated on thin (approx. 250A) silver films, and the electrical resistance of the silver was measured in situ to detect any penetration of atomic oxygen through the BN and Si3N4 materials. In the presence of atomic oxygen, silver oxidizes to form silver oxide, which has a much higher electrical resistance than pure silver. Permeation of atomic oxygen through BN, as indicated by an increase in the electrical resistance of the silver underneath, was observed in both the inflight and ground based experiments. In contrast, no permeation of atomic oxygen through Si3N4 was observed in either the inflight or ground based experiments. The ground based results show good qualitative correlation with the LEO flight results, indicating that ground based facilities such as the one at Los Alamos National Lab can reproduce space flight data from LEO

    Student teamwork: developing virtual support for team projects

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    In the 21st century team working increasingly requires online cooperative skills as well as more traditional skills associated with face to face team working. Virtual team working differs from face to face team working in a number of respects, such as interpreting the alternatives to visual cues, adapting to synchronous communication, developing trust and cohesion and cultural interpretations. However, co-located student teams working within higher education can only simulate team working as it might be experienced in organisations today. For example, students can learn from their mistakes in a non-threatening environment, colleagues tend to be established friends and assessing teamwork encourages behaviour such as “free-riding”. Using a prototyping approach, which involves students and tutors, a system has been designed to support learners engaged in team working. This system helps students to achieve to their full potential and appreciate issues surrounding virtual teamwork. The Guardian Agent system enables teams to allocate project tasks and agree ground rules for the team according to individuals’ preferences. Results from four cycles of its use are presented, together with modifications arising from iterations of testing. The results show that students find the system useful in preparing for team working, and have encouraged further development of the system

    A comparison of ground-based and space flight data: Atomic oxygen reactions with boron nitride and silicon nitride

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    The effects of atomic oxygen on boron nitride (BN) and silicon nitride (Si3N4) have been studied in low Earth orbit (LEO) flight experiments and in a ground-based simulation facility at Los Alamos National Laboratory. Both the in-flight and ground-based experiments employed the materials coated over thin (approx 250 Angstrom) silver films whose electrical resistance was measured in situ to detect penetration of atomic oxygen through the BN and Si3N4 materials. In the presence of atomic oxygen, silver oxidizes to form silver oxide, which has a much higher electrical resistance than pure silver. Permeation of atomic oxygen through BN, as indicated by an increase in the electrical resistance of the silver underneath, was observed in both the in-flight and ground-based experiments. In contrast, no permeation of atomic oxygen through Si3N4 was observed in either the in-flight or ground-based experiments. The ground-based results show good qualitative correlation with the LEO flight results, thus validating the simulation fidelity of the ground-based facility in terms of reproducing LEO flight results

    Localisation in focal epilepsy: a practical guide

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    The semiology of epileptic seizures reflects activation, or dysfunction, of areas of brain (often termed the symptomatogenic zone) as a seizure begins and evolves. Specific semiologies in focal epilepsies provide an insight into the location of the seizure onset zone, which is particularly important for presurgical epilepsy assessment. The correct diagnosis of paroxysmal events also depends on the clinician being familiar with the spectrum of semiologies. Here, we summarise the current literature on localisation in focal epilepsies using illustrative cases and discussing possible pitfalls in localisation

    Preoperative language mapping using navigated TMS compared with extra-operative direct cortical stimulation using intracranial electrodes: A case report

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    Highlights 1. rTMS provides a non-invasive means of performing pre-operative language mapping. 2. Sensitivity and specificity in epilepsy patients is lower than reported in tumour surgery. 3. Future methodological improvements may improve this

    Ostracoda from Lee Point on Shoal Bay, Northern Australia: part 3, podocopina (cytheracea)

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    The littoral environments present in Shoal Bay, Northern Territory (Australia) show a high diversity of ostracods cyther&aacute;ceos (51 genera and 97 species). Probably this diversity is due to three factors: (1) marine environments warm and well oxygenated leading to a high level of biological productivity, (2) shallow marine environments favorable for the accumulation of material conch&iacute;fero post mortem, and (3) a location central in the way of dispersal on the continental shelf between the regions of the Pacific and Southeast Asia. A particular feature of this fauna Cytherscea is that some genres, such as Alocopocythere, can be traced back to the Cretaceous when it first appeared in the shallow waters of the Tethys. In this overlay component of the ancient ostracods are the dominant fauna in partnerships of the modern Indo / Pacific, such as gender Keiji. While the Cytheracea ostracods are the dominant groups, especially the Cypridacea marine Bairdiacea and Plstycopina, are well represented and are quite different (fide Whatley et al., 1995, 1996). We describe here a new genre, Paraxestoleberis, and 15 new species: Dentiby&iacute;here multituberosa, Dampiercythere papillolineata, Neocy&iacute;heromorpha papilloporosa, Loxoconcha catas&iacute;eros, Semicyrherura gamma, Callistocy&iacute;here cookei, Loxocorniculum koolpionyahensis, Ke&uacute;ia interim, K. profundosculpia, K. parademissa, Quasibradleya leepoin&iacute;ensis, Actinocy&iacute;hereis gippsi, Henryhowella sinespinosa, Pon&iacute;icocy&iacute;hereis spatulospinosa and Paraxestoleberis posteroacuminata. Due to the limited material obtained, 16 species are kept in open nomenclature: Bythoceratina sp. Corallicy&iacute;here sp. Venericythere sp. Tanella sp. Loxocorniculum sp. 1 L. sp. 2, Gambiella sp. Javanella sp. Paradoxostoma sp. Neomonoceratina sp., Bradley (sl) sp. Echinocytbereis (sl) sp. Pla&iacute;ycy&iacute;hereis? sp. Alocopocy&iacute;here sp. Xestoleberis sp. and Paraxestoleberis sp. The remaining 66 species have been described previously in other areas.<br /
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