187 research outputs found

    Coherent GISAXS Scattering and Phase Retrieval Using DWBA

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    We have developed a 3 dimensional Coherent Diffraction Imaging algorithm to retrieve phases of diffraction patterns of samples in Grazing Incidence Small Angle X-ray Scattering (GISAXS) experiments. The algorithm interprets the diffraction patterns using the Distorted-Wave Born Approximation (DWBA) instead of the Born Approximation (BA), as in this case the existence of a reflected beam from the substrate causes the diffraction pattern to deviate significantly from the simple Fourier transform of the object. Detailed computer simulations show that the algorithm works. Verification with real experiments is planned.Comment: 11 pages, 4 figures, 1 Supplementary informatio

    New Developments in the Application of Synchrotron Radiation to Material Science

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    Recent developments in the application of synchrotrons radiation to materials science are discussed, using techniques which exploit the high brilliance of the newer synchrotrons sources, such as microbeam techniques and correlation spectroscopy. These include studies of environmental systems, residual stress, slow dynamics of condensed matter systems and studies of liquid surfaces and thin magnetic films

    Partial Crystallinity in Alkyl Side Chain Polymers Dictates Surface Freezing

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    We have studied the structure of a novel crystalline surface monolayer on top of a disordered melt of the same material [poly(n-alkyl acrylate)s] using grazing incidence x-ray diffraction. The grazing incidence x-ray diffraction, surface tension, and bulk latent heat results show that side chains crystallize except the nine methylene units of the alkyl side chains closest to the polymer backbone. The partial crystallinity along with a thicker surface layer, due to the additional length of the linker group, explains why the difference between the surface order-to-disorder transition temperature and bulk melting temperature increases with a decrease in the length of the alkyl side chain

    Effect of Surface Freezing on Meniscus Relaxation in Side Chain Comb Polymers

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    We have observed a sharp slowing down of the relaxation of the liquid meniscus for polydn-alkyl acrylate) at temperatures where there are no abrupt changes in bulk viscosity or surface tension. This slowing down is due to the formation of a surface-ordered monolayer above the bulk melting temperatures. X-ray photon correlation spectroscopy measurements reveal that the surface capillary fluctuations are also significantly slower due to the formation of the ordered monolayer for film thicknesses comparable to that of the precursor films. The slowing down of the precursor film dynamics is responsible for slower meniscus relaxation below the surface ordering transition temperature

    How sustainable practices influence guests’ willingness to pay a price premium in Fiji

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    Purpose This study seeks to determine the effect of sustainable practices on willingness to pay a price premium (WTPP) in the hotels and resorts in the Fiji islands. It will also assess how implementing these sustainable practices influences guest re-visit intentions. Design/methodology/approach A qualitative research technique was used which included in-depth interview sessions with ten Fijian resort managers and 15 hotel guests. The website of Etic Hotels was also used to gather data about the green practices provided by resorts and hotels. A non-random purposive sampling method was used to select respondents. Findings Results indicate that implementing sustainability practices has significantly and positively affected guest intentions to return to Fijian Hotels and resorts. The results also demonstrated that customers are willing to pay a higher price for the use of environmentally friendly practices in Fiji's hotels and resorts. Originality/value Though a few studies have been conducted examining the linkages between sustainable practices and the Fijian hotel industry, this article is a novel exploration of the use of sustainable practices in hotels and resorts and how they influence guest re-visit intentions and WTPP in Fiji Islands

    1988 Update of the Indiana Highway Cost Allocation Study

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    Association between Helicobacter pylori infection and increased risk of typhoid fever

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    Helicobacter pylori infection has been reported to increase the risk of cholera. This nested case-control study was conducted to determine whether H. pylori infection is associated with occurrence of typhoid fever. Eighty-three case subjects of culture-proven typhoid fever were identified through a 1-year surveillance of subjects aged 0-40 years in an urban slum. Two age- and sex-matched neighborhood control subjects were concurrently selected for each case subject. Serum anti-H. pylori immunoglobulin G antibodies were measured in case and neighborhood control subjects. For determining other risk factors, 2 additional community control subjects per case were selected. There was a significant association between the presence of serum anti-H. pylori immunoglobulin G antibodies and typhoid fever (adjusted odds ratio, 2.03; 95% confidence interval, 1.02-4.01). Illiteracy, being part of a nuclear family, nonuse of soap, and consumption of ice cream were also associated with a significantly greater risk of typhoid fever. This study provides the first empiric evidence that H. pylori infection is associated with an increased risk of typhoid fever

    Dayalbagh: An eco-village model for environment conservation

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    With the development of world towards industrialization, globalization, higher economic growth, population growth and living standards, the consumption of natural resources has been raised a lot. However, there is a limited capacity of our planet to meet the increasing demands for natural resources and to absorb emissions and wastes resulting from us. Ecovillage is a solution for healing the planet as it demonstrates a viable, sustainable human and planetary future. In this research paper Ecovillage design patterns will be analyzed and evaluated for environmental conservation. Case study of Dayalbagh is also presented to evaluate its performance as an Ecovillage

    Simple and Effective Multi-Paragraph Reading Comprehension

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    We consider the problem of adapting neural paragraph-level question answering models to the case where entire documents are given as input. Our proposed solution trains models to produce well calibrated confidence scores for their results on individual paragraphs. We sample multiple paragraphs from the documents during training, and use a shared-normalization training objective that encourages the model to produce globally correct output. We combine this method with a state-of-the-art pipeline for training models on document QA data. Experiments demonstrate strong performance on several document QA datasets. Overall, we are able to achieve a score of 71.3 F1 on the web portion of TriviaQA, a large improvement from the 56.7 F1 of the previous best system.Comment: 11 pages, updated a referenc
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