6,117 research outputs found
Developing TRACKER - Portable Monitoring System using Kalman Filtering to Track Rotational Movement of Bridges
The combined effects of flooding and scour are the primary causes of bridge failure over flowing water. Improvements in structural health monitoring and inertial sensors have led to the development of advanced monitoring systems that can provide bridge owners with detailed information on the performance of the structure and allow informed decisions to be made about time-critical safety issues following a storm event. However, such systems remain prohibitively expensive for the majority of smaller structures which make up the wider transport network. This thesis details the development of a robust, portable data acquisition logger (TRACK ER), which can be used to target vulnerable infrastructure during a storm event to increase the resilience of the wider transport network.
TRACKER uses condition monitoring, recording quasi-static and dynamic deformations, to track the performance of a bridge under the combined effects of storm loading. A benefit of this method is that it requires no direct input force or prior knowledge of the bridge model. Traditionally, tiltmeters or accelerometers are used to measure rotation for structural health monitoring purposes but such sensors can struggle to isolate rotation from translational acceleration if the structure is linearly accelerating. Gyroscopes offer improved rotational measurement capabilities but gyroscope measurements are known to drift over time as a result of the iterative process of converting rate gyroscope data. This thesis will explore gyroscopes as a complementary sensor to accelerometers and introduce a Kalman filter that combines both inertial sensors measurement data to obtain optimised rotation data. To improve the performance of the Kalman filter, the filter is adapted to automatically update the process and noise measurement values.
TRACKER, a robust, portable data acquisition logger, was developed and equipped with inertial sensors to provide a stand-alone system that can be rapidly deployed to target vulnerable infrastructure. Verification of the new logger was performed under controlled laboratory conditions to prove the validity of the new logger. The rotational data showed good agreement with rotational measurements obtained from an industry gold-standard vision-based measurement system. TRACKER was deployed on a variety of in-service bridges using different loading scenarios to demonstrate the ability of the new logging system, including loading from ambient weather conditions. TRACKER successfully tracked the performance of the structures, proving the ability of the logger to track the quasi-static and dynamic deformations of a structure during loading from traffic and environmental conditions
Contributions of temporal encodings of voicing, voicelessness, fundamental frequency, and amplitude variation to audiovisual and auditory speech perception
Auditory and audio-visual speech perception was investigated using auditory signals of invariant spectral envelope that temporally encoded the presence of voiced and voiceless excitation, variations in amplitude envelope and F-0. In experiment 1, the contribution of the timing of voicing was compared in consonant identification to the additional effects of variations in F-0 and the amplitude of voiced speech. In audio-visual conditions only, amplitude variation slightly increased accuracy globally and for manner features. F-0 variation slightly increased overall accuracy and manner perception in auditory and audio-visual conditions. Experiment 2 examined consonant information derived from the presence and amplitude variation of voiceless speech in addition to that from voicing, F-0, and voiced speech amplitude. Binary indication of voiceless excitation improved accuracy overall and for voicing and manner. The amplitude variation of voiceless speech produced only a small increment in place of articulation scores. A final experiment examined audio-visual sentence perception using encodings of voiceless excitation and amplitude variation added to a signal representing voicing and F-0. There was a contribution of amplitude variation to sentence perception, but not of voiceless excitation. The timing of voiced and voiceless excitation appears to be the major temporal cues to consonant identity. (C) 1999 Acoustical Society of America. [S0001-4966(99)01410-1]
Creep Fed Lambs
This report details the results of tests comparing creep-fed vs. non-creep-fed lambs
Perceived Preparation in Prospective Career Ready Students Attending a Rural High School in South Carolina
The purpose of this study was to investigate the perceptions of the resources and opportunities available to rural students that contribute to their career readiness particularly essential soft skills. The study was designed to identify critical factors that shape workplace skills of prospective career ready students in a rural high school to inform programs and practices focused on preparing students for the workplace. I analyzed WIN data (the assessment in South Carolina to determine career readiness) from the spring 2018 administration to describe student-level results by readiness levels and demographics. Using a descriptive qualitative design, I interviewed community stakeholders in local workforce development to explore their perceptions of workforce readiness.
In this study, rural community stakeholders expressed soft skills such as communication, and personal responsibility as critical skills needed in local workplaces. Furthermore that schools assist students in acquiring these skills by holding them accountable for expectations such as attendance, being on time, appropriate dress and wearing identification badges. Overwhelmingly, these community stakeholders cited workplace experience as the most critical factor in preparing graduates for local employment. Relatedly, study participants reported that graduates who are familiar with their work tend to experience contentment in the workplace which encourages the growth of consistent workforces in rural areas.
The primary significance of this study is to educational leaders seeking to ensure career readiness in South Carolina. By revealing the perceptions of stakeholders, educators can gain insight into the critical factors of career readiness. This research can influence educational practices by serving as a guide for project-based learning, collaborative work groups, on-site work experiences, technology integration, creating and developing ideas and products, and interpersonal skills. For scholarship and research, this study serves as a basis for further research to give a voice to the perceptions of graduates who met career ready measures during their first year of work. The findings from this study can inform policymakers seeking to support and expand current career pathways for South Carolina graduates
Trust and trustworthiness
What is it to trust someone? What is it for someone to be trustworthy? These are the two main questions that this paper addresses. There are various situations that can be described as ones of trust, but this paper considers the issue of trust between individuals. In it, I suggest that trust is distinct from reliance or cases where someone asks for something on the expectation that it will be done due to the different attitude taken by the trustor. I argue that the trustor takes Holton's 'participant stance' and this distinguishes trust from reliance. I argue that trustworthiness is different from reliability and that an account of trustworthiness cannot be successful whilst ignoring the point that aligning trustworthiness with reliability removes the virtue from being trustworthy. On the question of what it is distinguishes trustworthiness from reliability, I argue that the distinction is in the opportunity for the trustee to act against the wishes of the trustor and the trustee's consideration of the value of the trust that has been placed in them by the trustor
Analyzing community resilience as an emergent property of dynamic social-ecological systems
This is the final version of the article. Available from the publisher via the DOI in this record.Community resilience is widely promoted so that communities can respond positively to a range of risks, including shocks, extreme events, and other changes. Although much research has identified characteristics or capacities that confer resilience, resilience is more than simply the sum of these. Resilience is an emergent propertyāthe capacities are linked and act together. We present an empirical analysis of five different capacities and assess how interactions between them confer resilience in two coastal communities in Cornwall, UK. These capacities are place attachment, leadership, community cohesion and efficacy, community networks, and knowledge and learning. Based on a survey and focus group discussions, our results show that residents draw on these capacities in different combinations, enabling resilience in diverse ways. This provides a dynamic and socially nuanced perspective on community resilience as process, potentially informing theory and practice of conservation, disaster risk reduction, climate change adaptation, and community development.This work was supported by the Natural
Environment Research Council (NERC) through Belmont Forum
project, Multi-scale Adaptations to Global Change in Coastlines
(MAGIC) project no: NE/L008807/1, and by the Economic and
Social Research Council (ESRC) through the UK South West
Doctoral Training Centre Studentship Award 2013 (Environment,
Energy and Resilience)
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