3,029 research outputs found

    Neutron resonance capture applied to some prehistoric bronze axes

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    The elemental analysis of materials and objects on the basis of neutron resonance capture by nuclei as a function of neutron energy is briefly explained. The feasibility of neutron resonance capture analysis (NRCA) is demonstrated with five prehistoric “bronze” axes of different kinds and complex elemental compositions. Attention is paid to the occurrence of indium as a trace element in these artefacts

    Giving voters what they want? Party orientation perceptions and preferences in the British electorate

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    Some of the most important propositions in the political marketing literature hinge on assumptions about the electorate. In particular, voters are presumed to react in different ways to different orientations or postures. Yet there are theoretical reasons for questioning some of these assumptions, and certainly they have seldom been empirically tested. Here, we focus on one prominent example of political marketing research: Lees-Marshment’s orientations’ model. We investigate how the public reacts to product and market orientation, whether they see a trade-off between the two (a point in dispute among political marketing scholars), and whether partisans differ from non-partisan voters by being more inclined to value product over market orientation. Evidence from two mass sample surveys of the British public (both conducted online by YouGov) demonstrates important heterogeneity within the electorate, casts doubt on the core assumptions underlying some political marketing arguments and raises broader questions about what voters are looking for in a party

    Systematic reduction of Hyperspectral Images for high-throughput Plastic Characterization

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    Hyperspectral Imaging (HSI) combines microscopy and spectroscopy to assess the spatial distribution of spectroscopically active compounds in objects, and has diverse applications in food quality control, pharmaceutical processes, and waste sorting. However, due to the large size of HSI datasets, it can be challenging to analyze and store them within a reasonable digital infrastructure, especially in waste sorting where speed and data storage resources are limited. Additionally, as with most spectroscopic data, there is significant redundancy, making pixel and variable selection crucial for retaining chemical information. Recent high-tech developments in chemometrics enable automated and evidence-based data reduction, which can substantially enhance the speed and performance of Non-Negative Matrix Factorization (NMF), a widely used algorithm for chemical resolution of HSI data. By recovering the pure contribution maps and spectral profiles of distributed compounds, NMF can provide evidence-based sorting decisions for efficient waste management. To improve the quality and efficiency of data analysis on hyperspectral imaging (HSI) data, we apply a convex-hull method to select essential pixels and wavelengths and remove uninformative and redundant information. This process minimizes computational strain and effectively eliminates highly mixed pixels. By reducing data redundancy, data investigation and analysis become more straightforward, as demonstrated in both simulated and real HSI data for plastic sorting

    Mono/Multi-material Characterization Using Hyperspectral Images and Multi-Block Non-Negative Matrix Factorization

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    Plastic sorting is a very essential step in waste management, especially due to the presence of multilayer plastics. These monomaterial and multimaterial plastics are widely employed to enhance the functional properties of packaging, combining beneficial properties in thickness, mechanical strength, and heat tolerance. However, materials containing multiple polymer species need to be pretreated before they can be recycled as monomaterials and therefore should not end up in monomaterial streams. Industry 4.0 has significantly improved materials sorting of plastic packaging in speed and accuracy compared to manual sorting, specifically through Near Infrared Hyperspectral Imaging (NIRHSI) that provides an automated, fast, and accurate material characterization, without sample preparation. Identification of multimaterials with HSI however requires novel dedicated approaches for chemical pattern recognition. Non negative Matrix Factorization, NMF, is widely used for the chemical resolution of hyperspectral images. Chemically relevant model constraints may make it specifically valuable to identify multilayer plastics through HSI. Specifically, Multi Block Non Negative Matrix Factorization (MBNMF) with correspondence among different chemical species constraint may be used to evaluate the presence or absence of particular polymer species. To translate the MBNMF model into an evidence based sorting decision, we extended the model with an F test to distinguish between monomaterial and multimaterial objects. The benefits of our new approach, MBNMF, were illustrated by the identification of several plastic waste objects

    Effects of stimulus duration on audio-visual synchrony perception

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    The integration of visual and auditory inputs in the human brain occurs only if the components are perceived in temporal proximity, that is, when the intermodal time difference falls within the so-called subjective synchrony range. We used the midpoint of this range to estimate the point of subjective simultaneity (PSS). We measured the PSS for audio-visual (AV) stimuli in a synchrony judgment task, in which subjects had to judge a given AV stimulus using three response categories (audio first, synchronous, video first). The relevant stimulus manipulation was the duration of the auditory and visual components. Results for unimodal auditory and visual stimuli have shown that the perceived onset shifts to relatively later positions with increasing stimulus duration. These unimodal shifts should be reflected in changing PSS values, when AV stimuli with different durations of the auditory and visual components are used. The results for 17 subjects showed indeed a significant shift of the PSS for different duration combinations of the stimulus components. Because the shifts were approximately equal for duration changes in either of the components, no net shift of the PSS was observed as long as the durations of the two components were equal. This result indicates the need to appropriately account for unimodal timing effects when quantifying intermodal synchrony perceptio

    Environmental sustainability and gynaecological surgery:Which factors influence behaviour? An interview study

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    OBJECTIVE: To assess the various factors that influence environmentally sustainable behaviour in gynaecological surgery and examine the differences between gynaecologists and residents.DESIGN: An interview study.SETTING: Academic and non-academic hospitals in the Netherlands.POPULATION: Gynaecologists (n = 10) and residents (n = 6).METHODS: Thematic analysis of semi-structured interviews to determine the various factors that influence environmentally sustainable behaviour in gynaecological surgery and to examine the differences between gynaecologists and residents. By using the Desmond framework and the COM-B BCW, both organisational and individual factors related to behaviour were considered.MAIN OUTCOME MEASURES: Factors that influence environmentally sustainable behaviour.RESULTS: Awareness is increasing but practical knowledge is insufficient. It is crucial to integrate education on the environmental impact of everyday decisions for residents and gynaecologists. Gynaecologists make their own choices but residents' autonomy is limited. There is the necessity to provide environmentally sustainable surgical equipment without compromising other standards. There is a need for a societal change that encourages safe and open communication about environmental sustainability. To transition to environmentally sustainable practices, leadership, time, collaboration with the industry and supportive regulatory changes are essential.CONCLUSION: This study lays the groundwork for promoting more environmentally sustainable behaviour in gynaecological surgery. The key recommendations, addressing hospital regulations, leadership, policy revisions, collaboration with the industry, guideline development and education, offer practical steps towards a more sustainable healthcare system. Encouraging environmentally sustainable practices should be embraced to enhance the well-being of both our planet and our population, driving us closer to a more environmentally sustainable future in healthcare.</p
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