Modeling of a magneto-rheological (MR) fluid damper using a self tuning fuzzy mechanism

A magneto-rheological (MR) fluid damper is a semi-active control device that has recently begun to receive more attention in the vibration control community. However, the inherent nonlinear nature of the MR fluid damper makes it challenging to use this device to achieve high damping control system performance. Therefore the development of an accurate modeling method for a MR fluid damper is necessary to take advantage of its unique characteristics. Our goal was to develop an alternative method for modeling a MR fluid damper by using a self tuning fuzzy (STF) method based on neural technique. The behavior of the researched damper is directly estimated through a fuzzy mapping system. In order to improve the accuracy of the STF model, a back propagation and a gradient descent method are used to train online the fuzzy parameters to minimize the model error function. A series of simulations had been done to validate the effectiveness of the suggested modeling method when compared with the data measured from experiments on a test rig with a researched MR fluid damper. Finally, modeling results show that the proposed STF interference system trained online by using neural technique could describe well the behavior of the MR fluid damper without need of calculation time for generating the model parameters.

Breastfeeding self-efficacy and alternative techniques to overcome maternal or infant breastfeeding challenges : a retrospective descriptive study

Background: Breastfeeding is the internationally accepted ideal in infant feeding. Ensuring mothers and babies receive optimal benefits, in both the short and long term, is dependent upon the successful establishment of breastfeeding in the first week. Many maternal and infant challenges can occur during the establishment of breastfeeding (Lactogenesis II). There are also many methods and devices (alternative techniques) which can be used to help, but the majority do not have an evidence-base. The mother.s self-confidence (self-efficacy) can be challenged by these unexpected circumstances, but understanding of the relationship is unclear. Method: This descriptive study used mail survey (including the Breastfeeding Self-Efficacy Scale . Short Form) to obtain the mother.s reports of their self-efficacy and their breastfeeding experience during the first week following birth, as well as actual use of alternative techniques. This study included all mothers of full term healthy singleton infants from one private hospital in Brisbane who began any breastfeeding. The data collection took place from November 2008 to February 2009. Ethical approval was granted from the research site and QUT Human Research Ethics Committee. Results: A total of 128 questionnaires were returned, a response rate of 56.9%. The sample was dissimilar to the Queensland population with regard to age, income, and education level, all of which were higher in this study. The sample was similar to the Queensland population in terms of parity and marital status. The rate of use of alternative techniques was 48.3%. The mean breastfeeding self-efficacy score of those who used any alternative technique was 43.43 (SD=12.19), and for those who did not, it was 58.32 (SD=7.40). Kruskal-Wallis analysis identified that the median self efficacy score for those who used alternative techniques was significantly lower than median self efficacy scores for those who did not use alternative techniques. The reasons women used alternative techniques varied widely, and their knowledge of alternative techniques was good. Conclusion: This study is the first to document breastfeeding self-efficacy of women who used alternative techniques to support their breastfeeding goals in the first week postpartum. An individualised clinical intervention to develop women.s self-efficacy with breastfeeding is important to assist mother/infant dyads encountering challenges to breastfeeding in the first week postpartum.

A nonlinear PI and backstepping based controller for tractor-steerable trailer influenced by slip

Autonomous guidance of agricultural vehiclesis vital as mechanized farming production becomes more prevalent. It is crucial that tractor-trailers are guided with accuracy in both lateral and longitudinal directions, whilst being affected by large disturbance forces, or slips, owing to uncertain and undulating terrain. Successful research has been concentrated on trajectory control which can provide longitudinal and lateral accuracy if the vehicle moves without sliding, and the trailer is passive. In this paper, the problem of robust trajectory tracking along straight and circular paths of a tractor-steerable trailer is addressed. By utilizing a robust combination of backstepping and nonlinear PI control, a robust, nonlinear controller is proposed. For vehicles subjected to sliding, the proposed controller makes the lateral deviations and the orientation errors of the tractor and trailer converge to a neighborhood near the origin. Simulation results are presented to illustrate that the suggested controller ensures precise trajectory tracking in the presence of slip.

Unlocking black box models of leadership effectiveness: Exploring alternative research and policy metaphors

There is an intimate interconnectivity between policy guidelines defining reform and the delineation of what research methods would be subsequently applied to determine reform success. Research is guided as much by the metaphors describing it as by the ensuing empirical definition of actions of results obtained from it. In a call for different reform policy metaphors Lumby and English (2010) note, “The primary responsibility for the parlous state of education... lies with the policy makers that have racked our schools with reductive and dehumanizing processes, following the metaphors of market efficiency, and leadership models based on accounting and the characteristics of machine bureaucracy” (p. 127)

The power of historical causal components involved in engaging at risk youth at three alternative schools

This article addresses the causal powers associated with the social phenomena of alternative schooling for youth at risk. It stems from a doctoral thesis, Alternative Schooling Programs for At Risk Youth – Three Case Studies which addresses wider issues integral to alternative schooling: youth at risk, alternative schooling models, and literacy. This article explores one aspect of alternative schooling: the historical causal factors involved in the establishment and continuance of three alternative case study models in Queensland, Australia. By adhering to Bhaskar’s transformational model of social activity (TMSA) , social structures and individuals will be analytically distinguished to uncover their separate causal powers and how these have effected the establishment and continuance of three alternative schools.

A different algebraic analysis of the ZUC stream cipher

Existing algebraic analyses of the ZUC cipher indicate that the cipher should be secure against algebraic attacks. In this paper, we present an alternative algebraic analysis method for the ZUC stream cipher, where a combiner is used to represent the nonlinear function and to derive equations representing the cipher. Using this approach, the initial states of ZUC can be recovered from 2^97 observed words of keystream, with a complexity of 2^282 operations. This method is more successful when applied to a modified version of ZUC, where the number of output words per clock is increased. If the cipher outputs 120 bits of keystream per clock, the attack can succeed with 219 observed keystream bits and 2^47 operations. Therefore, the security of ZUC against algebraic attack could be significantly reduced if its throughput was to be increased for efficiency.

Predicting psychologists’ intentions to integrate complementary and alternative therapies (CAT) into their practice.

This study assessed the validity of a scale measuring psychologists' attitudes towards complementary and alternative therapies and compared the attitudes of psychologists with a previous sample of psychology students. The scale, derived from existing measures for medical professionals and previously tested on a sample of psychology students, was completed by practising psychologists (N = 122). The data were factor analysed, and three correlated subscales were identified, assessing the perceived importance of knowledge about available therapies, attitudes towards integration with psychological practice, and concerns about associated risks of use. This structure was similar, but not identical, to that found in a previous sample of psychology students; however, psychologists expressed more concern for risks associated with integration and were less likely to hold a positive attitude towards integration. This scale will be useful in gauging changes in psychologists' attitudes towards integrative practice over time.

Integrating complementary and alternative therapies into psychological practice : A qualitative analysis

Although complementary and alternative therapies (CATs) are utilised widely for treating psychological disorders, little research has examined psychologists' beliefs about integrating CAT into psychological practice. Six practicing psychologists and six psychology students were interviewed about their CAT integration beliefs, in particular integrating CAT into clinical practice via recommending CATs, offering referrals to CAT practitioners, or undertaking training to utilise CATs within psychological practice. Guided broadly from a theory of planned behaviour perspective, participants raised a number of costs and benefits, discussed referent groups who would influence their decisions, and suggested motivators and barriers for integration. A number of additional themes were raised, including risks, such as the possibility of litigation and the need for clear Society guidelines, as most participants were unclear about what constitutes appropriate practice. Identifying these themes serves as an important initial step to informing discussion and policy for this emerging practice issue within psychology.

The taxation of multinational banks : alternative apportionment through a unitary taxation regime aligning with economic reality

The taxation of multinational banks currently is governed by the general principles of international tax. However, it is arguable that there are characteristics exclusive to multinational banks that may warrant the consideration of a separate taxing regime. This article argues that because of the unique nature of multinational banks, the traditional international tax rules governing jurisdiction to tax and allocation of income do not produce a result which is optimal, as it does not reflect economic reality. That is, the current system does not produce a result that accurately reflects the economic source of the income or the location of the economic activity. The suggested alternative is unitary taxation using global formulary apportionment. Formulary apportionment is considered as an alternative that reflects economic reality by recognising the unique nature of multinational banks and allocating the income to the location of the economic activity. The unique nature of multinational banking is recognised in the fact that formulary apportionment does not attempt to undertake a transactional division of a highly integrated multinational entity. Rather, it allocates income to the jurisdictions based on an economically justifiable formula. Starting from this recognition, the purpose of this article is to demonstrate that formulary apportionment is a theoretically superior (or optimal) model for the taxation of multinational banks. An optimal regime, for the purposes of this article, is considered to be one that distributes the taxing rights in an equitable manner between the relevant jurisdictions, while, simultaneously allowing decisions of the international banks to be tax neutral. In this sense, neutrality is viewed as an economic concept and equity is regarded as a legal concept. A neutral tax system is one in which tax rules do not affect economic choices about commercial activities. Neutrality will ideally be across jurisdictions as well as across traditional and non-traditional industries. The primary focus of this article is jurisdictional neutrality. A system that distributes taxing rights in an equitable manner between the relevant jurisdictions ensures that each country receives its fair share of tax revenue. Given the increase in multinational banking, jurisdictions should be concerned that they are receiving their fair share. Inter-nation equity is concerned with re-determining the proper division of the tax base among countries. Richard and Peggy Musgrave argue that sharing of the tax base by countries of source should be seen as a matter of inter-nation equity requiring international cooperation. The rights of the jurisdiction of residency will also be at issue. To this extent, while it is agreed that inter-nation equity is an essential attribute to an international tax regime, there is no universal agreement as to how to achieve it. The current system attempts to achieve such equity through a combined residency and source regime, with the transfer pricing rules used to apportion income between the relevant jurisdictions. However, this article suggests, that as an alternative to the current regime, equity would be achieved through formulary apportionment. Opposition to formulary apportionment is generally based on the argument that it is not a theoretically superior (or optimal) model because of the implementation difficulties. Yet these are two separate issues. As such, this article is divided into two core parts. The first part examines the theoretical soundness of the formulary apportionment model concluding that it is theoretically superior to the arm’s length pricing requirement of the traditional transfer pricing regime. The second part examines the practical implications of accepting formulary apportionment as an optimal model with a view to disclosing the issues that arise when a formulary apportionment regime is adopted. Prior to an analysis of the theoretical and practical application of formulary apportionment to multinational banks, the unique nature of these banks is considered. The article concludes that, while there are significant implementation, compliance, and enforcement issues to overcome, the unitary taxation model may be theoretically superior to the current arm’s length model which applies to multinational banks. This conclusion is based on the unitary taxation model providing greater alignment with the unique features of these banks.

Modelling the interaction of keratinocytes and fibroblasts during normal and abnormal wound healing processes

The crosstalk between fibroblasts and keratinocytes is a vital component of the wound healing process, and involves the activity of a number of growth factors and cytokines. In this work, we develop a mathematical model of this crosstalk in order to elucidate the effects of these interactions on the regeneration of collagen in a wound that heals by second intention. We consider the role of four components that strongly affect this process: transforming growth factor-beta, platelet-derived growth factor, interleukin-1 and keratinocyte growth factor. The impact of this network of interactions on the degradation of an initial fibrin clot, as well as its subsequent replacement by a matrix that is mainly comprised of collagen, is described through an eight-component system of nonlinear partial differential equations. Numerical results, obtained in a two-dimensional domain, highlight key aspects of this multifarious process such as reepithelialisation. The model is shown to reproduce many of the important features of normal wound healing. In addition, we use the model to simulate the treatment of two pathological cases: chronic hypoxia, which can lead to chronic wounds; and prolonged inflammation, which has been shown to lead to hypertrophic scarring. We find that our model predictions are qualitatively in agreement with previously reported observations, and provide an alternative pathway for gaining insight into this complex biological process.

Alternative primary sources for studying Australian television history : an annotated list of online private collections

It is possible to write many different histories of Australian television, and these different histories draw on different primary sources. The ABC of Drama, for example, draws on the ABC Document Archives (Jacka 1991). Most of the information for Images and Industry: television drama production in Australia is taken from original interviews with television production staff (Moran 1985). Ending the Affair, as well as archival work, draws on ‘over ten years of watching … Australian television current affairs’ (Turner 2005, xiii). Moran’s Guide to Australian TV Series draws exhaustively on extant archives: the ABC Document Archives, material sourced through the ABC Drama department, the Australian Film Commission, the library of the Australian Film, Television and Radio School, and the Australian Film Institute (Moran 1993, xi)...

Mean-field descriptions of collective migration with strong adhesion

Random walk models based on an exclusion process with contact effects are often used to represent collective migration where individual agents are affected by agent-to-agent adhesion. Traditional mean field representations of these processes take the form of a nonlinear diffusion equation which, for strong adhesion, does not predict the averaged discrete behavior. We propose an alternative suite of mean-field representations, showing that collective migration with strong adhesion can be accurately represented using a moment closure approach.

Efficient preconditioning of the method of lines for solving nonlinear two-sided space-fractional diffusion equations

A standard method for the numerical solution of partial differential equations (PDEs) is the method of lines. In this approach the PDE is discretised in space using �finite di�fferences or similar techniques, and the resulting semidiscrete problem in time is integrated using an initial value problem solver. A significant challenge when applying the method of lines to fractional PDEs is that the non-local nature of the fractional derivatives results in a discretised system where each equation involves contributions from many (possibly every) spatial node(s). This has important consequences for the effi�ciency of the numerical solver. First, since the cost of evaluating the discrete equations is high, it is essential to minimise the number of evaluations required to advance the solution in time. Second, since the Jacobian matrix of the system is dense (partially or fully), methods that avoid the need to form and factorise this matrix are preferred. In this paper, we consider a nonlinear two-sided space-fractional di�ffusion equation in one spatial dimension. A key contribution of this paper is to demonstrate how an eff�ective preconditioner is crucial for improving the effi�ciency of the method of lines for solving this equation. In particular, we show how to construct suitable banded approximations to the system Jacobian for preconditioning purposes that permit high orders and large stepsizes to be used in the temporal integration, without requiring dense matrices to be formed. The results of numerical experiments are presented that demonstrate the effectiveness of this approach.