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The discomfort from exposure to low frequency rotational and translational vibration
No full textThe discomfort arising from exposure to low frequency oscillation is a matter of some interest in many forms of transport. However there is a dearth of knowledge about the discomfort which arises from exposure to vibration at low frequencies. This thesis investigates the effects of frequency, magnitude and direction arising from the exposure of seated passengers to roll, pitch, fore-and-aft and lateral oscillation at frequencies between 0.2 and 1.6 Hz. The objectives of this research were to investigate whether: • the discomfort arising from low frequency rotational and translational oscillation could be satisfactorily predicted based on knowledge of the acceleration in the plane of the seat; • the presence of a backrest would exacerbate discomfort during both rotational and translational oscillation; • the adoption of different postures during vibration would affect the reported discomfort. Achieving these objectives required determination of the frequency-dependence and magnitude dependence of discomfort arising from exposure to rotational and translational oscillation at frequencies less than 1.6 Hz. The investigations used the psychophysical method of magnitude estimation to determine the rate of growth of discomfort with increasing vibration magnitude, and contours of equivalent discomfort. Four studies within-axes contributed new information about the effect of vibration frequency on the discomfort arising from exposure to rotational and translational oscillation. A series of smaller studies determined the relationship between the discomfort arising within different axes, and a study investigated the effect of posture. Each study employed 12 subjects. At frequencies greater than 0.4 Hz, exposure to motion in the rotational axes caused greater discomfort than the equivalent motion in the translational axes. At lower frequencies, the acceleration in the plane of the seat was a good predictor of the discomfort experienced irrespective of whether oscillation was in the rotational or translational axes, except when the discomfort arising from fore-and-aft and pitch oscillation on a seat with no backrest was compared. It was found that the presence of a backrest exacerbated discomfort during rotational oscillation at frequencies greater than 0.4 Hz but reduced discomfort during fore-and-aft oscillation. The presence of a backrest increased the incidence of discomfort arising at the head neck interface. The ability of subjects to voluntarily control their posture was found to be low, except at the lowest frequencies. The sensitivity of subjects to angular displacement increased at approximately 6 dB per octave at frequencies greater than 0.4 Hz, whereas during translational acceleration on a flat rigid seat the rate of increase in sensitivity was lower at approximately 3 dB per octave. When subjects were seated on a rigid seat with backrest and exposed to translation acceleration the discomfort arising from motion was approximately independent of frequency over the range 0.2 to 1.6 Hz. The observed effect of vibration magnitude on the frequency dependence was small, but variations in the rate of growth of discomfort with frequency indicate this magnitude-dependence would be in settings where a greater range of accelerations was present. important Existing standardised methods of prediction (e.g. BS 6841) were compared to the results with minimal modification (linear extension of the asymptotic frequency weightings). Where discomfort is dominated by oscillation in a single axis at a single input (e.g. fore-and-aft oscillation with no backrest) the prediction was considered sufficient for many practical purposes. However, where the presence of a backrest influenced discomfort the quality of prediction deteriorated markedly and the standardised method cannot be recommended.</p
Discomfort from sinusoidal oscillation in the roll and lateral axes at frequencies between 0.2 and 1.6 Hz
No full textDiscomfort from sinusoidal oscillation in the pitch and fore-and-aft axes at frequencies between 0.2 and 1.6 Hz
No full textLow frequency pitch and fore-and-aft oscillations arise in many modes of transport. Pitch oscillation rotates a seat through the gravity vector giving rise to a fore-and-aft acceleration in the plane of the seat: the measurement of fore-and-aft acceleration does not discriminate between the component of this acceleration arising from pitch and the component arising from horizontal acceleration in the fore-and-aft direction. The objectives of this study were to investigate whether fore-and-aft acceleration in the plane of the seat was an adequate predictor of vibration discomfort arising from low frequency oscillation in both the pitch and fore-and-aft axes, and to determine the effect of a backrest on discomfort during pitch and fore-and-aft oscillation at low frequencies. Twelve male subjects used the method of magnitude estimation to judge the discomfort produced by sinusoidal oscillations in the pitch and fore-and-aft axes at 10 frequencies between 0.2 and 1.6 Hz, while seated with and without a backrest. For both pitch and fore-and-aft oscillation, the rate of growth of discomfort with increasing vibration magnitude decreased with increasing frequency of oscillation, indicating that the frequency-dependence of discomfort is magnitude-dependent. At frequencies greater than about 0.4 Hz with a backrest, and at frequencies greater than about 0.8 Hz without a backrest, fore-and-aft acceleration in the plane of the seat arising from pitch oscillation caused greater discomfort than the same acceleration produced by fore-and-aft oscillation. A backrest increased discomfort with pitch oscillation at frequencies greater than about 0.63 Hz, but tended to decrease discomfort during fore-and-aft oscillation. The prediction of discomfort caused by low frequency pitch and fore-and-aft oscillation requires that both components are measured and assessed according to their separate effects, taking into account any beneficial and detrimental effects of a backres
Author interview: Q and A with Dr Ian Sanjay Patel on we’re here because you were there: immigration and the end of empire
No full textIn this author interview, we speak to Dr Ian Sanjay Patel about his new book, We’re Here Because You Were There: Immigration and the End of Empire, which explores post-war immigration laws, the afterlives of British imperial citizenship and related attempts to reimagine and rejuvenate British imperialism after 1945. Contributing to transnational histories of decolonisation, the book also explores the interconnections between human rights, post-war migration and international diplomacy. Author Interview with Dr Ian Sanjay Patel, author of We’re Here Because You Were There: Immigration and the End of Empire. Verso. 2021
Providence College Faculty Author Series 2017-2018: Ian Levy
No full textIn this installment of the Faculty Authors Series, Ian Levy (Theology, Providence College) discusses his newest book, Introducing Medieval Biblical Interpretation: The Senses of Scripture in Premodern Exegesis
Providence College Faculty Author Series 2017-2018: Ian Levy
No full textIn this installment of the Faculty Authors Series, Ian Levy (Theology, Providence College) discusses his newest book, Introducing Medieval Biblical Interpretation: The Senses of Scripture in Premodern Exegesis
Author interview: Q and A with Dr Paul Ian Campbell, author of education, retirement and career transitions for ‘black’ ex-professional footballers
No full textIn this author interview, we speak to Dr Paul Ian Campbell about his new book, Education, Retirement and Career Transitions for ‘Black’ Ex-Professional Footballers: ‘From Being Idolised to Stacking Shelves’, which explores black British male ex-professional footballers’ experiences of, and preparations for, retirement and career transition
Ian Bogost at X-Media Lab: serious gaming
No full textVideo games are usually viewed as a form of escapism: pure entertainment and shoot-em-up fantasy. But increasingly, games are being recognised as educational tools, or as deliverers of social or political messages. This evolving medium is taking on complex environments and issues, and providing a platform for people to explore a world or situation in an interactive way. In this talk at the X Media Lab in Sydney, video game theorist and designer Ian Bogost gives an overview of how video games can benefit human existence.
Ian Bogost is author of "Unit Operations: An Approach to Videogame Criticism", recently listed among "50 books for everyone in the game industry". He also wrote "Persuasive Games: The Expressive Power of Videogames", and was co-author of "Racing the Beam: The Atari Video Computer System". He is widely considered an influential thinker and doer in the videogame industry and research community.
 
Democracy Sausage with Mark Kenny: How to be a liberal with Ian Dunt
No full textOn this Democracy Sausage Extra, Ian Dunt - host of the Oh God, What Now? podcast and author of How to be a liberal - joins Mark Kenny to discuss the history of liberal thought, how it has shaped present day politics, and the origins of the ‘culture wars’. Have the culture wars emerged out of the failures of liberalism? Why haven’t contemporary political actors done more to protect people from prejudice and the tyranny of the majority? And is liberalism a natural corollary to democracy? On this Democracy Sausage Extra, author, political journalist and broadcaster Ian Dunt joins Professor Mark Kenny to discuss the history of political thought, present day politics, and liberalism’s trajectory
Ian Hancock - Head of Department of History, Faculty of Arts, ANU
No full textThis audio interview with Ian Hancock is part of the Emeritus Faculty's Oral History Program involving retired members of ANU who were part of the university in its earlier life. The Oral History Program was initiated and developed by ANU Emeritus Faculty as a contribution to university and community understanding of the beginnings and development of ANU over the past seven decades. Emeritus Faculty has a special interest in this period since the Faculty's membership includes many of the people who helped shape ANU in those early days, to make it the preeminent university it is today.
Ian held Teaching appointments in the Department of History, Faculty of Arts for many years and for many was Head of the Department. As seen in his CV Ian has broad interests among these being a preeminent author of past and present members of the Australian Liberal Party
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