An optimized online secondary path modeling method for single-channel feedback ANC systems

This paper proposes a new method for online secondary path modeling in feedback active noise control (ANC) systems. In practical cases, the secondary path is usually time varying. For these cases, online modeling of secondary path is required to ensure convergence of the system. In literature the secondary path estimation is usually performed offline, prior to online modeling, where in the proposed system there is no need for using offline estimation. The proposed method consists of two steps: a noise controller which is based on an FxLMS algorithm, and a variable step size (VSS) LMS algorithm which is used to adapt the modeling filter with the secondary path. In order to increase performance of the algorithm in a faster convergence and accurate performance, we stop the VSS-LMS algorithm at the optimum point. The results of computer simulation shown in this paper indicate effectiveness of the proposed method.

A new feedback ANC system approach

We propose a new active noise control (ANC) technique. The technique has a feedback structure to have a simple configuration in practical implementation. In this approach, the secondary path is modelled online to ensure convergence of the system as the secondary paths are practically time varying or non-linear. The proposed method consists of two steps: a noise controller which is based on a modified FxLMS algorithm, and a new variable step size (VSS) LMS algorithm which is used to adapt the modelling filter with the secondary path. The proposed algorithm stops injection of the white noise at the optimum point and reactivate the injection during the operation, if needed, to maintain performance of the system. Eliminating continuous injection of the white noise increases the performance of the proposed method significantly and makes it more desirable for practical ANC systems. The computer simulations are presented to show the effectiveness of the proposed method.

The Human Fertilisation and Embryology Act 2008 : restrictions on the creation of “saviour siblings” and the relevance of the harm principle

This paper provides an overview of the regulatory developments in the UK which impact on the use of in vitro fertilization (IVF) and embryo screening techniques for the creation of “saviour siblings.” Prior to the changes implemented under the Human Fertilisation and Embryology Act 2008, this specific use of IVF was not addressed by the legislative framework and regulated only by way of policy issued by the Human Fertilisation and Embryology Authority (HFEA). Following the implementation of the statutory reforms, a number of restrictive conditions are now imposed on the face of the legislation. This paper considers whether there is any justification for restricting access to IVF and pre-implantation tissue typing for the creation of “saviour siblings.” The analysis is undertaken by examining the normative factors that have guided the development of the UK regulatory approach prior to the 2008 legislative reforms. The approach adopted in relation to the “saviour sibling” issue is compared to more general HFEA policy, which has prioritized the notion of reproductive choice and determined that restrictions on access are only justified on the basis of harm considerations.

Stigmergy within web modelling languages : positive feedback mechanisms

Stigmergy is a biological term originally used when discussing insect or swarm behaviour, and describes a model supporting environment-based communication separating artefacts from agents. This phenomenon is demonstrated in the behavior of ants and their food foraging supported by pheromone trails, or similarly termites and their termite nest building process. What is interesting with this mechanism is that highly organized societies are formed without an apparent central management function. We see design features in Web sites that mimic stigmergic mechanisms as part of the User Interface and we have created generalizations of these patterns. Software development and Web site development techniques have evolved significantly over the past 20 years. Recent progress in this area proposes languages to model web applications to facilitate the nuances specific to these developments. These modeling languages provide a suitable framework for building reusable components encapsulating our design patterns of stigmergy. We hypothesize that incorporating stigmergy as a separate feature of a site’s primary function will ultimately lead to enhanced user coordination.

Open up the building : architectural relevance of building-users and their participations

As buildings have become more advanced and complex, our ability to understand how they are operated and managed has diminished. Modern technologies have given us systems to look after us but it appears to have taken away our say in how we like our environment to be managed. The aim of this paper is to discuss our research concerning spaces that are sensitive to changing needs and allow building-users to have a certain level of freedom to understand and control their environment. We discuss why, what we call the Active Layer, is needed in modern buildings; how building inhabitants are to interact with it; and the development of interface prototypes to test consequences of having the Active Layer in our environment.

Feedback consistencies and inconsistencies : eight mentors’ observations on one preservice teacher’s lesson

Mentors play a key role in developing preservice teachers for their chosen careers and providing feedback appears as a significant relational interaction between the mentor and mentee that assists in guiding the mentee’s practices. Yet, what are mentors’ perspectives on providing feedback to their mentees? In this case study, eight mentors viewed a professional video recorded science lesson facilitated by a final-year preservice teacher during practicum for the purposes of providing oral feedback in a simulated mentor-mentee discussion. Findings showed that mentors’ feedback was variable in both their positive feedback and constructive criticisms and, in one case, the feedback was contrasting in nature. Implications are discussed, including preservice teachers receiving feedback from more than one mentor and universities researching the design of valid and reliable tools to guide mentors’ oral feedback.

Using formative feedback to identify and support first year chemistry students with missing or misconceptions. A Practice Report

Students entering tertiary studies possess a diverse range of prior experiences in their academic preparation for tertiary chemistry so academics need tools to enable them to respond to issues in diversity in conceptual models possessed by entering students. Concept inventories can be used to provide formative feedback to help students identify concepts that they need to address to improve construction of subsequent understanding enabling their learning. Modular, formative learning activities that can be administered inside or outside of class in first year chemistry courses have been developed. These activities address key missing and mis-conceptions possessed by incoming student. Engagement in these learning activities by students and academics will help shift the culture of diagnostic and formative assessment within the tertiary context and address issues around the secondary/tertiary transition. This diagnostic/intervention framework is currently being trialed across five Australian tertiary institutions encompassing a large heterogeneous sample of students.

Towards engaged consumption : new sources of inspiration for eco-feedback design

Eco-feedback interventions are capable of producing reductions in household energy consumption. Yet less is known about exactly how this reduction is achieved, how to maximise user engagement, or how to effectively translate engagement into energy saving. This paper discusses design opportunities for eco-feedback systems through observations of domestic energy use in both Western and rural developing world contexts. Drawing on case studies from these two contexts including 21 empirical interviews, we present an alternative framework for human-resource interaction, highlighting design opportunities for a transition towards more engaged and sustainable energy consumption among users.

The importance of individual difference : examining anthropomorphic tendency and responses to spokes-characters

Anthropomorphism is a cognitive bias, which occurs when individuals see human characteristics in a non-human agent, object or animal. Anthropomorphism is especially interesting to marketers, because once anthropomorphic bias has been triggered, it can lead to a greater feeling of connectedness to a non-human agent (Tam, Lee and Chao, 2013), the emulation of behaviours (Aggarwal and McGill, 2012) or greater attribution of brand personality and brand liking (Delbaere, McQuarrie and Phillips, 2011). Importantly, research now shows that levels of this tendency vary between individuals (Waytz, Cacioppo and Epley, 2010), but research to date has failed to focus on how anthropomorphic tendency influences individual responses to marketing communications messages. Spokes-characters present an ideal context through which to examine this gap, given that they function as personified brands, designed to trigger consumer anthropomorphic tendency. Further, little is understood about how spokes-characters operate and which consumers will prefer them to their human counterparts. Like anthropomorphic research, much empirical work to date has focused on design and outcomes, examining the sender’s encoding process and the feedback generated, but ignoring the individual decoding process that is so important to understanding individual differences and message effectiveness. The current research employs three experiments using an online survey with stimulus exposure to show that anthropomorphic tendency, personality similarity and spokes-character type all have relevance to the understanding of this complex relationship. Study one and two indicate that while a human spokesperson is still preferred by many, higher levels of anthropomorphic tendency increase likeability of cartoon spokes characters. Study three highlights the importance of personality similarity, which further increases likability. Additional analyses provide key findings concerning the nature of anthropomorphic tendency as an individual difference and trait. This research contributes to a greater understanding of anthropomorphism theory and fills existing gaps in the consumer psychology and marketing communications literature.

Effect of the mediator in feedback mode-based SECM interrogation of indium tin-oxide and boron-doped diamond electrodes

Indium tin-oxide (ITO) and polycrystalline boron-doped diamond (BDD) have been examined in detail using the scanning electrochemical microscopy technique in feedback mode. For the interrogation of electrodes made from these materials, the choice of mediator has been varied. Using Ru(CN) 4− 6 (aq), ferrocene methanol (FcMeOH), Fe(CN) 3− 6 (aq) and Ru(NH 3) 3+ 6 (aq), approach curve experiments have been performed, and for purposes of comparison, calculations of the apparent heterogeneous electron transfer rates (k app) have been made using these data. In general, it would appear that values of k app are affected mainly by the position of the mediator reversible potential relative to the relevant semiconductor band edge (associated with majority carriers). For both the ITO (n type) and BDD (p type) electrodes, charge transfer is impeded and values are very low when using FcMeOH and Fe(CN) 3− 6 (aq) as mediators, and the use of Ru(NH 3) 3+ 6(aq) results in the largest value of k app. With ITO, the surface is chemically homogeneous and no variation is observed for any given mediator. Data is also presented where the potential of the ITO electrode is fixed using a ratio of the mediators Fe(CN) 3− 6(aq) and Fe(CN) 4− 6(aq). In stark contrast, the BDD electrode is quite the opposite and a range of k app values are observed for all mediators depending on the position on the surface. Both electrode surfaces are very flat and very smooth, and hence, for BDD, variations in feedback current imply a variation in the electrochemical activity. A comparison of the feedback current where the substrate is biased and unbiased shows a surprising degree of proportionality.

Superactivation of metal electrode surfaces and its relevance to COads oxidation at fuel cell anodes

The inhibiting effect of COads on platinum-based anodes is a major problem in the development of ambient temperature, polyelectrolyte membrane-type fuel cells. One of the unusual features of the response for the oxidative removal of the species in question is that the response observed for this reaction in the positive sweep is highly dependent on the CO admission potential, for example, when the COads is formed in the Hads region it undergoes oxidation at unusually low potentials. Such behaviour is attributed here to hydrogen activation of the platinum surface, with the result that oxide mediators (and COads oxidation) occurs at an earlier stage of the positive sweep. It is also demonstrated, for both platinum and gold in acid solution, that dramatic premonolayer oxidation responses may be observed following suitable preactivation of the electrode surfaces. It is suggested that the defect state of a solid electrode surface is an important variable whose investigation may yield improved fuel cell anode performance.

Kaleidoscope : shaping a better future through a stakeholder approach to widespread organisational change

The main focus of ‘Kaleidoscope: Reframing evaluation through a stakeholder approach to sustainable, cultural change in Higher Education’ is to develop a set of principles to guide user-led engagement in widespread organisational change and maximise its impact. The word kaleidoscope represents the unique lens through which each institution will need to view their cultural specificity and local context through an extensive process of collaboration and engagement, followed by communication and dissemination. Kaleidoscope has particular relevance when new approaches to learning and teaching evaluation are introduced by tertiary institutions. Building on the Reframe Project, which involved three years of user-led consultation and was designed to meet stakeholders’ needs, QUT successfully introduced a new evaluation framework in 2013 across the university. Reframe was evidence based, involved scholarly reflection and was founded on a strong theoretical framework. The evolution of the evaluation framework included analysis of scholarly literature and environmental scans across the higher education sector (Alderman, et al., 2012), researched development of conceptual theory (Alderman, et al., in press 2013), incorporated the stakeholder voice and framed within project management principles (Alderman & Melanie, 2012). Kaleidoscope’s objectives are for QUT to develop its research-based stakeholder approach to distil the successful experience exhibited in the Reframe Project into a transferable set of guidelines for use by other tertiary institutions across the sectors. These guidelines will assist others to design, develop, and deploy, their own culturally specific widespread organisational change informed by stakeholder engagement and organisational buy-in. It is intended that these guidelines will promote, support and enable other tertiary institutions to embark on their own projects and maximise the impact. In correlation with a our conference paper, this round table presents the Draft Guidelines and Framework ready for external peer review by evaluation practitioners, as part of Kaleidoscope’s dissemination (Hinton & Gannaway, 2011) applying illuminative evaluation theory (Parlett & Hamilton, 1976), through conference workshops and linked round table discussions (Shapiro, et al., 1983; Jacobs, 2000).

Curiosity to cupboard : self reported disengagement with energy use feedback over time

This paper discusses findings made during a study of energy use feedback in the home (eco-feedback), well after the novelty has worn off. Contributing towards four important knowledge gaps in the research, we explore eco-feedback over longer time scales, focusing on instances where the feedback was not of lasting benefit to users rather than when it was. Drawing from 23 semi-structured interviews with Australian householders, we found that an initially high level of engagement gave way over time to disinterest, neglect and in certain cases, technical malfunction. Additionally, preconceptions concerned with the “purpose” of the feedback were found to affect use. We propose expanding the scope of enquiry for eco-feedback in several ways, and describe how eco-feedback that better supports decision-making in the “maintenance phase”, i.e. once the initial novelty has worn off, may be key to longer term engagement.

Learner-focused evaluation cycles : facilitating learning using feedforward, concurrent and feedback evaluation

There is a growing trend to offer students learning opportunities that are flexible, innovative and engaging. As educators embrace student-centred agile teaching and learning methodologies, which require continuous reflection and adaptation, the need to evaluate students’ learning in a timely manner has become more pressing. Conventional evaluation surveys currently dominate the evaluation landscape internationally, despite recognition that they are insufficient to effectively evaluate curriculum and teaching quality. Surveys often: (1) fail to address the issues for which educators need feedback, (2) constrain student voice, (3) have low response rates and (4) occur too late to benefit current students. Consequently, this paper explores principles of effective feedback to propose a framework for learner-focused evaluation. We apply a three-stage control model, involving feedforward, concurrent and feedback evaluation, to investigate the intersection of assessment and evaluation in agile learning environments. We conclude that learner-focused evaluation cycles can be used to guide action so that evaluation is not undertaken simply for the benefit of future offerings, but rather to benefit current students by allowing ‘real-time’ learning activities to be adapted in the moment. As a result, students become co-producers of learning and evaluation becomes a meaningful, responsive dialogue between students and their instructors.

Characteristics of nontuberculous mycobacteria from a municipal water distribution system and their relevance to human infections

This thesis documented pathogenic species of nontuberculous mycobacteria in the Brisbane water distribution system. When water and shower aerosol strains were compared with human strains of mycobacteria, the study found that the likelihood of acquiring infection from municipal water was specific for four main species. The method for isolation of mycobacteria from water was refined, followed by sampling from 220 sites across Brisbane. A variety of species (incl 15 pathogens) were identified and genotypically compared to human strains. For M. abscessus and M. lentiflavum, water strains clustered with human strains. Pathogenic strains of M. kansasii were found, though non-pathogenic strains dominated. Waterborne strains of M. fortuitum differed to human strains. Extensive home sampling of 20 patients with NTM disease, supported the theory that the risk of acquiring NTM from water or shower aerosols appears species specific for M. avium, M. kansasii, M. lentiflavum and M. abscessus.