7,726 research outputs found

    Capturing in-situ Feelings and Experiences of Public Transit Riders Using Smartphones

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    High-density urban environments are susceptible to ever-growing traffic congestion issues, which speaks to the importance of implementing and maintaining effective and sustainable transportation networks. While transit oriented developments offer the potential to help mitigate traffic congestion issues, transit networks ought to be safe and reliable for ideal transit-user communities. As such, it is imperative to capture meaningful data regarding transit experiences, and deduce how transit networks can be enhanced or modified to continually maintain ideal transit experiences. Historically speaking, it has been relatively tricky to measure how people feel whilst using public transportation, without leaning on recall memory to explain such phenomena. Recall memory can be vague and is often less detailed than recording in-situ observations of the transit-user community. This thesis explores the feasibility of using smartphones to capture meaningful in-situ data to leverage the benefits of the Experience Sampling Method (ESM), while also addressing some limitations. Students travelled along Grand River Transit bus routes in Waterloo, Ontario from Wilfrid Laurier University to Conestoga Mall and back using alternate routes. The mobile survey captured qualitative and quantitative data from 145 students to explore variations in wellbeing, and the extent to which environmental variables can influence transit experiences. There were many findings to consider for future research, especially the overall role anxiety played on transit experiences. In addition, the results indicate that the methodology is appropriate for further research, and can be applied to a wide range of research topics. In particular, it is recommended that a similar study be applied to a much larger, and more representative sample of the transit-user community. Future considerations are discussed as key considerations to leverage the benefits of ESM research, and the promise it can bring towards the enhancement of transit experiences and the cohesion of transit-user communities

    Precarious future for an urban minority: ethnic Azeris in Russia

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    This repository item contains a single issue of Behind the Breaking News, a briefing published from 1999 to 2009 by the Boston University Institute for the Study of Conflict, Ideology, and Policy

    Principal component analysis and perturbation theory–based robust damage detection of multifunctional aircraft structure

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    A fundamental problem in structural damage detection is to define an efficient feature to calculate a damage index. Furthermore, due to perturbations from various sources, we also need to define a rigorous threshold whose overtaking indicates the presence of damages. In this article, we develop a robust damage detection methodology based on principal component analysis. We first present an original damage index based on projection of the separation matrix, and then, we drive a novel adaptive threshold that does not rely on statistical assumptions. This threshold is analytic, and it is based on matrix perturbation theory. The efficiency of the method is illustrated using simulations of a composite smart structure and experimental results performed on a conformal load-bearing antenna structure laboratory test

    Perturbation Analysis for Robust Damage Detection with Application to Multifunctional Aircraft Structures

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    The most widely known form of multifunctional aircraft structure is smart structures for structural health monitoring (SHM). The aim is to provide automated systems whose purposes are to identify and to characterize possible damage within structures by using a network of actuators and sensors. Unfortunately, environmental and operational variability render many of the proposed damage detection methods difficult to successfully be applied. In this paper, an original robust damage detection approach using output-only vibration data is proposed. It is based on independent component analysis and matrix perturbation analysis, where an analytical threshold is proposed to get rid of statistical assumptions usually performed in damage detection approach. The effectiveness of the proposed SHM method is demonstrated numerically using finite element simulations and experimentally through a conformal load-bearing antenna structure and composite plates instrumented with piezoelectric ceramic materials.FUI MSIE (Pole Astech
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