Robust saturated control of human-induced floor vibrations via a proof-mass actuator

This paper is concerned with the design of a robust active vibration control system that makes use of a proof-mass actuator for the mitigation of human-induced vibrations in floor structures. Ideally, velocity feedback control (VFC) is unconditionally stable and robust to spillover effects, interlacing of poles and zeros of collocated control is then accomplished. However, the use of a proof-mass actuator influences the system dynamics and the alternating pole-zero pattern of the system formed by the actuator and structure is no longer fulfilled. However, a controlled migration of the two zeros of the root locus plot at the origin, resulting from the acceleration output, can be achieved by adding a feed-through term (FTT) to the structure acceleration output. That is, the FTT enables us to control the position of a pair of complex conjugate zeros (an anti-resonance in the frequency domain). This paper proposes the introduction of an FTT designed in such a way that the anti-resonance at the origin is located between the actuator resonance and the structure fundamental resonance. Hence, an integral controller leads to infinite gain margin and significant phase margin. Simulation and experimental results on a concrete slab strip have validated the proposed control strategy. Significant improvements in the stability properties compared with VFC are reported

‘Without occupation you don't exist’: Occupational engagement and mental illness

This article has been made available through the Brunel Open Access Publishing Fund.This phenomenological study explores the meanings of work for people living with severe and enduring mental health conditions. The participants were three women and seven men who were attending a mental health day centre. Data were collected through up to three depth interviews with each participant over 18 months. The interviews were digitally recorded, transcribed verbatim, and analysed according to phenomenological principles. Two overarching themes were identified. Building and maintaining an occupational identity expressed the ways in which participants used occupations as the building blocks of an evolving identity. Most of the participants wanted to work, and participation in occupations was seen as essential to recovery from mental ill-health. Work and other ways of belonging encapsulated the need to feel connected to others. Many of the participants envisaged working as a way of achieving this. The longitudinal nature of the study facilitated engagement with the developing narratives and exploration of the changes and consistencies in the participants' meaning making about their occupations. Implications for understanding individuals' occupational participation which enhances a sense of self and promotes feelings of belonging are identified

The meaning and experience of work in the context of severe and enduring mental health problems: An interpretative phenomenological analysis

This is the author's final version of the article. The final publication is available from the link below. Copyright @ 2013 IOS Press and the Authors.Research into mental health and employment has indicated that work holds multiple meanings for people with mental health problems. This paper reports findings from a phenomenological study which aimed to understand the complexity of these meanings by exploration of the perspectives of one individual who was considering returning to work. Data were gathered through a series of three interviews carried out over a period of 18 months. Three themes were identified – Beliefs and Values about Work, Working with a Mental Health Problem, and Planning for the Future. Analysis and interpretation facilitated understandings of what work represented for the participant. What this study has contributed to the evidence base is a deeper understanding of the multiple meanings of work, and the varied roles that work may play in contributing to meaning and quality of life for people with mental health problems

Telling Miller’s Tale: A Reply to David Yassky

A recent article by Professor David Yassky suggests that there is a segment of legal academia that dissents from the Standard model and has started to generate alternatives to the Standard Model. Denning and Reynolds critique that part of Yassky\u27s theory dismissing United States v. Miller as providing the basis for an individual rights interpretation of the Second Amendment

Chemical application of diffusion quantum Monte Carlo

The diffusion quantum Monte Carlo (QMC) method gives a stochastic solution to the Schroedinger equation. This approach is receiving increasing attention in chemical applications as a result of its high accuracy. However, reducing statistical uncertainty remains a priority because chemical effects are often obtained as small differences of large numbers. As an example, the single-triplet splitting of the energy of the methylene molecule CH sub 2 is given. The QMC algorithm was implemented on the CYBER 205, first as a direct transcription of the algorithm running on the VAX 11/780, and second by explicitly writing vector code for all loops longer than a crossover length C. The speed of the codes relative to one another as a function of C, and relative to the VAX, are discussed. The computational time dependence obtained versus the number of basis functions is discussed and this is compared with that obtained from traditional quantum chemistry codes and that obtained from traditional computer architectures

Effect of vicarious fear learning on children's heart rate responses and attentional bias for novel animals

Research with children has shown that vicarious learning can result in changes to 2 of Lang's (1968) 3 anxiety response systems: subjective report and behavioral avoidance. The current study extended this research by exploring the effect of vicarious learning on physiological responses (Lang's final response system) and attentional bias. The study used Askew and Field's (2007) vicarious learning procedure and demonstrated fear-related increases in children's cognitive, behavioral, and physiological responses. Cognitive and behavioral changes were retested 1 week and 1 month later, and remained elevated. In addition, a visual search task demonstrated that fear-related vicarious learning creates an attentional bias for novel animals, which is moderated by increases in fear beliefs during learning. The findings demonstrate that vicarious learning leads to lasting changes in all 3 of Lang's anxiety response systems and is sufficient to create attentional bias to threat in children

The nurses that roared: nurses from history who found their voices and challenged the status quo

In this article we explore how nurses from history challenged norms of nursing and society, and consider how they can influence and inspire nurses today. We discuss the role of nurses in the fight for women’s suffrage, campaigning for the vote and caring for women who suffered in their fight to achieve it, and present examples of outstanding bravery in the past and present day. The article contains examples of the bravery of some relatively unknown nurses in wartime, who also fought for equality and inclusion, and nurses who challenged the care of marginalised groups, campaigning for improved treatment, sometimes at great personal cost. Finally we consider the courage of present-day nurses. Drawing on the global campaign of “Nursing Now”, we suggest that learning from these exceptional nurses and acknowledging and highlighting their contribution can inspire us to strengthen and promote nursing and to empower women globally