Robust estimation of tear film surface quality in lateral shearing interferometry

Interferometry is a sensitive technique for recording tear film surface irregularities in a noninvasive manner. At the same time, the technique is hindered by natural eye movements resulting in measurement noise. Estimating tear film surface quality from interferograms can be reduced to a spatial-average-localized weighted estimate of the first harmonic of the interference fringes. However, previously reported estimation techniques proved to perform poorly in cases where the pattern fringes were significantly disturbed. This can occur in cases of measuring tear film surface quality on a contact lens on the eye or in a dry eye. We present a new estimation technique for extracting the first harmonic from the interference fringes that combines the traditional spectral estimation techniques with morphological image processing techniques. The proposed technique proves to be more robust to changes in interference fringes caused by natural eye movements and the degree of dryness of the contact lens and corneal surfaces than its predecessors, resulting in tear film surface quality estimates that are less noisy

Online estimation of distorted power system signal parameters

An algorithm based on the concept of Kalman filtering is proposed in this paper for the estimation of power system signal attributes, like amplitude, frequency and phase angle. This technique can be used in protection relays, digital AVRs, DSTATCOMs, FACTS and other power electronics applications. Furthermore this algorithm is particularly suitable for the integration of distributed generation sources to power grids when fast and accurate detection of small variations of signal attributes are needed. Practical considerations such as the effect of noise, higher order harmonics, and computational issues of the algorithm are considered and tested in the paper. Several computer simulations are presented to highlight the usefulness of the proposed approach. Simulation results show that the proposed technique can simultaneously estimate the signal attributes, even if it is highly distorted due to the presence of non-linear loads and noise.

Closing the cultural distance gap: managing value-based knowledge in MNC by using MEP

Today more than ever, generating and managing knowledge is an essential source of competitive advantage for every organization, and particularly for Multinational corporations (MNC). However, despite the undisputed agreement about the importance of creating and managing knowledge, there are still a large number of corporations that act unethically or illegally. Clearly, there is a lack of attention in gaining more knowledge about the management of ethical knowledge in organizations. This paper refers to value-based knowledge, as the process of recognise and manage those values that stand at the heart of decision-making and action in organizations. In order to support MNCs in implementing value-based knowledge process, the managerial ethical profile (MEP) has been presented as a valuable tool to facilitate knowledge management process at both the intra-organizational network level and at the inter-organizational network level.

The applicability of biased estimation in model and model order selection

Biased estimation has the advantage of reducing the mean squared error (MSE) of an estimator. The question of interest is how biased estimation affects model selection. In this paper, we introduce biased estimation to a range of model selection criteria. Specifically, we analyze the performance of the minimum description length (MDL) criterion based on biased and unbiased estimation and compare it against modern model selection criteria such as Kay's conditional model order estimator (CME), the bootstrap and the more recently proposed hook-and-loop resampling based model selection. The advantages and limitations of the considered techniques are discussed. The results indicate that, in some cases, biased estimators can slightly improve the selection of the correct model. We also give an example for which the CME with an unbiased estimator fails, but could regain its power when a biased estimator is used.

Unmanned Aerial Vehicles UAVs attitude, height, motion estimation and control using visual systems

This paper presents an implementation of an aircraft pose and motion estimator using visual systems as the principal sensor for controlling an Unmanned Aerial Vehicle (UAV) or as a redundant system for an Inertial Measure Unit (IMU) and gyros sensors. First, we explore the applications of the unified theory for central catadioptric cameras for attitude and heading estimation, explaining how the skyline is projected on the catadioptric image and how it is segmented and used to calculate the UAV’s attitude. Then we use appearance images to obtain a visual compass, and we calculate the relative rotation and heading of the aerial vehicle. Additionally, we show the use of a stereo system to calculate the aircraft height and to measure the UAV’s motion. Finally, we present a visual tracking system based on Fuzzy controllers working in both a UAV and a camera pan and tilt platform. Every part is tested using the UAV COLIBRI platform to validate the different approaches, which include comparison of the estimated data with the inertial values measured onboard the helicopter platform and the validation of the tracking schemes on real flights.

Place value, multiplicativity, reunitizing and effective classroom teaching of decimal numeration

Student understanding of decimal number is poor (e.g., Baturo, 1998; Behr, Harel, Post & Lesh, 1992). This paper reports on a study which set out to determine the cognitive complexities inherent in decimal-number numeration and what teaching experiences need to be provided in order to facilitate an understanding of decimal-number numeration. The study gave rise to a theoretical model which incorporated three levels of knowledge. Interview tasks were developed from the model to probe 45 students’ understanding of these levels, and intervention episodes undertaken to help students construct the baseline knowledge of position and order (Level 1 knowledge) and an understanding of multiplicative structure (Level 3 knowledge). This paper describes the two interventions and reports on the results which suggest that helping students construct appropriate mental models is an efficient and effective teaching strategy.

Labelled silhouettes for human pose estimation

This paper proposes a new method of using foreground silhouette images for human pose estimation. Labels are introduced to the silhouette images, providing an extra layer of information that can be used in the model fitting process. The pixels in the silhouettes are labelled according to the corresponding body part in the model of the current fit, with the labels propagated into the silhouette of the next frame to be used in the fitting for the next frame. Both single and multi-view implementations are detailed, with results showing performance improvements over only using standard unlabelled silhouettes.

Central venous oxygen saturation monitoring

It has been established that mixed venous oxygen saturation (SvO2) reflects the balance between systemic oxygen deliver y and consumption. Literature indicates that it is a valuable clinical indicator and has good prognostic value early in patient course. This article aims to establish the usefulness of SvO2 as a clinical indicator. A secondary aim was to determine whether central venous oxygen saturation (ScvO2) and SvO2 are interchangeable. Of particular relevance to cardiac nurses is the link between decreased SvO2 and cardiac failure in patients with myocardial infarction, and with decline in myocardial function, clinical shock and arrhythmias. While absolute values ScvO2 and SvO2 are not interchangeable, ScvO2 and SvO2are equivalent in terms of clinical course. Additionally, ScvO2 monitoring is a safer and less costly alternative to SvO2 monitoring. It can be concluded that continuous ScvO2 monitoring should potentially be undertaken in patients at risk of haemodynamic instability.

Preventing consumer credit over-commitment and irresponsible lending in Australia

Mirroring the trends in other developed countries, levels of household debt in Australia have risen markedly in recent years. As one example, the total amount lent by banks to individuals has risen from $175.5 billion in August 1995 to $590.5 billion in August 2005.1 Consumer groups an~ media commentators here have long raised concerns about the risks of increasing levels of household debt and over-commitment, linking these issues at least in part to irresponsible lending practices. And more recently, the Reserve Bank Governor has also expressed concerns about the ability 'of some households to manage if personal or economic circumstances change.2

Art and the sublime : the paradox of indeterminacy unknowing and (dis)orientation in the presentation of the unpresentable

the (dis)orientation of thought in its encounter with art can be understood as the direct result of an encounter with indeterminacy as a lack in meaning. As an artist I am aware of how this indeterminacy impacts on the perceived value and authority of the artistic voice and in particular its value as a research voice. This paper explores this indeterminacy of meaning, as a profound and disturbing unknowing characteristic of the sublime and argues its value to advanced thought and for any methodological understanding of practice-led research. Lyotard described the sublime as an ‘understanding’ through which art and its associated practices may be able to resist an all too easy assimilation by the public as just a consumer commodity. His thought represents an attempt to both politically and philosophically understand art’s, and particularly abstract painting’s, affect as a state of profound and positive unknowing. To talk of the sublime in art is to speak of the suspension of any comfortable certainty in being and instead to engage with the real as a limit to meaning and knowing. It is to talk of the presentation of the unpresentable as a momentary but significant dissolution of representation. This understanding of the sublime is then further explored through the cultural phenomena of the monochrome painting and applied to the work of the two contemporary artists, Franz Erhard Walter and Günter Umberg. Initially the monochrome was understood as an attempt to go beyond traditional representation and present the unpresentable. In the one hundred years or so since that initial move this understanding has broadened. The monochrome now presents itself as a genre or even project within visual art but it still has much to teach us. In the concretely abstract and performative artworks of Franz Erhard Walter and Günter Umberg, traces of this ambition remain and their work can be seen to pose questions probing our understandings and experiences of artistic meaning, its value and the real.

Detection and Estimation of Nonstationary Power Transients

This chapter looks at issues of non-stationarity in determining when a transient has occurred and when it is possible to fit a linear model to a non-linear response. The first issue is associated with the detection of loss of damping of power system modes. When some control device such as an SVC fails, the operator needs to know whether the damping of key power system oscillation modes has deteriorated significantly. This question is posed here as an alarm detection problem rather than an identification problem to get a fast detection of a change. The second issue concerns when a significant disturbance has occurred and the operator is seeking to characterize the system oscillation. The disturbance initially is large giving a nonlinear response; this then decays and can then be smaller than the noise level ofnormal customer load changes. The difficulty is one of determining when a linear response can be reliably identified between the non-linear phase and the large noise phase of thesignal. The solution proposed in this chapter uses “Time-Frequency” analysis tools to assistthe extraction of the linear model.

Buying a sponsor's brand : the role of affective commitment to the sponsored team

Sponsorship is increasingly important in a firm's communication mix. Research to date has focused on the impact of sponsorship on brand awareness and its subsequent consequences for image congruency and consumer attitudes towards sponsors' brands. A lesser studied area is the effect of sponsorship on consumers' purchase intentions and behaviours. We argue that existing models of sponsorship driven purchase behaviour fail to account for affective commitment, which mediates relationship between affiliation with the team and social identification with the team. We propose a modified framework describing the effect of sponsorship on purchase intentions in the context of low and high performing sports teams. The framework is tested using structural equations modelling; employing PLS estimation and data collected via online survey of AFL chat room participants. Results confirm the role of affective commitment in sport sponsorship purchase intentions and indicate that team success has a significant influence on fans' purchase behaviours.

Respecting contractual intentions : balancing consumer expectations with the sanctity of contract in the context of standard form insurance contracts

It is the purpose of this article to examine the means curently available to judges to achieve a workable balance between providing appropriate consumer protection to signatories of standard form contractors while still retaining adequate respect for the sanctity of contract, and, based on this analysis, to determine whether a significantly greater scope of contract (re)construction is likely to become the norm in most common law jurisdictions in the coming decades.

Disclosure under the prescribed insurance contracts regime : Section 35 of the Insurance Contracts Act 1984 and consumer protection revisited

Section 35 of the Insurance Contracts Act 1984 requires insurers offering insurance policies in six prescribed areas "to clearly inform" prospective insureds of any departure their policies may constitute from the standard covers established by the Act and its accompanying Regulations. This prescribed insurance contracts regime was designed to remedy comprehension problems generated by the length and complexity of insurance documents and to alleviate misunderstanding over the terms and conditions of individual policies. This article examines the rationale underpinning s 35 and the prescribed insurance contracts regime and looks at the operation of the legislation with particular reference to home contents insurance in Australia. It is argued that the means whereby disclosure of derogation from standard cover may be effected largely negates the thrust of the prescribed insurance contract reform. Recommendations to address these operational deficiencies are made.