Integrated modelling of cost-effective siting and operation of flow-control infrastructure for river ecosystem conservation

Wetland and floodplain ecosystems along many regulated rivers are highly stressed, primarily due to a lack of environmental flows of appropriate magnitude, frequency, duration, and timing to support ecological functions. In the absence of increased environmental flows, the ecological health of river ecosystems can be enhanced by the operation of existing and new flow-control infrastructure (weirs and regulators) to return more natural environmental flow regimes to specific areas. However, determining the optimal investment and operation strategies over time is a complex task due to several factors including the multiple environmental values attached to wetlands, spatial and temporal heterogeneity and dependencies, nonlinearity, and time-dependent decisions. This makes for a very large number of decision variables over a long planning horizon. The focus of this paper is the development of a nonlinear integer programming model that accommodates these complexities. The mathematical objective aims to return the natural flow regime of key components of river ecosystems in terms of flood timing, flood duration, and interflood period. We applied a 2-stage recursive heuristic using tabu search to solve the model and tested it on the entire South Australian River Murray floodplain. We conclude that modern meta-heuristics can be used to solve the very complex nonlinear problems with spatial and temporal dependencies typical of environmental flow allocation in regulated river ecosystems. The model has been used to inform the investment in, and operation of, flow-control infrastructure in the South Australian River Murray.

Continuous corrosion rate measurement by noise resistance calculation

A commonly employed method of corrosion rate measurement is to determine the electrochemical impedance of the corroding material. One technique for estimating the impedance is the noise impedance calculation. While it has been shown to yield useful results, there are a number of problems that require attention. This paper identifies some of those problems-specifically, those of detrending and resolution-and provides a solution that allows continuous, time-varying noise resistance and noise impedance calculations to be performed with known time, frequency, and magnitude resolutions. Applications to synthetic and experimental data are included as illustrations

Adaptive fast finite-time multiple-surface sliding control for a class of uncertain non-linear systems

This paper concerns the adaptive fast finite-time multiple-surface sliding control (AFFTMSSC) problem for a class of high-order uncertain non-linear systems of which the upper bounds of the system uncertainties are unknown. By using the fast control Lyapunov function and the method of so-called adding a power integrator merging with adaptive technique, a recursive design procedure is provided, which guarantees the fast finite-time stability of the closed-loop system. Further, it is proved that the control input is bounded.

Elaborative relational structures in the research prose of sociology : an intercultural study

This paper investigates elaborative relational structures utilised by native English speaking and native Polish speaking scholars in sociology research articles written in English. The examined texts have been produced in American, Australian and Polish academic discourse communities. The study utilised the framework of the analysis of the rhetorical structure of tests (FARS) as an analytical tool (Golebiowski 2009, 2011). The following types of elaboration relations are discussed : amplification, extension, reformulation, explanation, instantiation and addition. Elaboration is analysed with respect to its textual function, frequency of employment, hierarchical location, recursiveness, discoursal prominence and explicitness. The elaborative systems in the examined texts are shown to be complex, with pervasive presence of multi-stage recursive structures. It is suggested that elaborativeness may be a general characteristic of the style of writing sociology, which, as a relatively new discipline, requires establishing of wide grounds for the proposed claims, where writers persuade their readers not only of the specific claims of their text, but also of frameworks of thought in which the claims are placed. It is hypothesized that the similarities in the elaborativeness across texts result from the shared stylistic conventions and traditions of the disciplinary research community of sociology, while differences in the mode of employment of elaboration relations are attributed to cultural norms and conventions as well as educational systems prevailing within the discourse communities constituting the social contexts of the studied texts.
Golebiowski, Z. (2011). Scholarly criticism across discourse communities. In Salager-Meyer, Françoise and Lewin, Beverly A. (eds), Crossed words : Criticism in scholarly writing, pp. 203-224, Peter Lang International Academic Publishers, Berlin, Germany.
Golebiowski Z. (2009). The use of contrastive strategies in a sociology research paper: A cross-cultural study. In Suomela-Salmi, Eija and Dervin, Fred (eds), Cross-linguistic and cross-cultural perspectives on academic discourse, pp. 165-186, John Benjamins Publishing Company, Philadelphia.

Inclusion in participatory research: what were the whitefellas doing in an Aboriginal health project?

Health research in indigenous communities, like many interactions between such communities and white-dominated institutions, has a chequered history leading to a three-fold decrement: suspicion and resistance to research that is seen as coming from outside of the community; a shortage of research generators and leaders within the community; and cumulative gaps in the research evidence base, both in terms of coverage of topics and in terms of meeting the priorities of the community.

Additionally, these decrements have been mistakenly located as problems being caused from within the community, rather than recognising that these are outcomes of wider contextual, historical and institutional factors and failings. Good research, as culturally appropriate, inclusive of community voices and meeting the needs and priorities of the community, is necessary in an increasingly evidence-based-practice culture within policy and health settings. Culturally safe research with and for indigenous communities has the potential to be empowering, and to bring community voices, views and experiences into the influential realm of'evidence.

This process of developing safe, appropriate and inclusive research is not straightforward: the decrements are recursive, with a shortage of connections between the community, its priorities and research. However, as the Healing Stories project that we discuss here has shown, it is possible to develop culturally safe participatory research by working with Elders from within the community and with leaders from within white institutions, in a spirit of reconciliation. The methods and findings of Healing Stories have been reported elsewhere, with an emphasis on the voices from the community; this chapter explores some of the 'behind the scenes' processes, from the perspective of the white researchers working from within white- dominated institutions.

After briefly describing the Healing Stories project, this chapter reflects on three parts of the participatory research process: getting started, leading together, and working together. The first of these considers laying the foundations for participatory research, working with Elders and leaders, and planning for inclusion, examining participatory research as a recognisable research design, with potential for rigour, cultural safety and inclusion. The second explores developing participatory methods, working with communities, and opportunities and choices for inclusion. The third examines the process of being participatory, working together and engaging in inclusion across the long-term commitment to the project.

Is there an app for that? Looking at possibilities and challenges of digital tools for literacy education

 Portable electronic devices such as the iPad are increasingly taking a place in contemporary childhood experiences including those of schooling (O'Mara & Laidlaw, 2011). As digital media theorists suggest, such new tools invite both "hope and fear" (Gee and Hayes, 2011, p.4), consistent with literacy innovations across history. In both Canada and Australia, educational stakeholders are looking to touch screen devices as having much promise, particularly within literacy education. This paper presentation examines the possibilities as well as the challenges and imagines the future of such digital tools within literacy education, looking at experiences and perspectives in Canada and Australia.
We take a qualitative ecological mode of inquiry approach to our data collection and analysis, drawing on complexity thinking (Davis & Sumara, 2006) to bring our multiple points of view together as diversely positioned educators. Within our individual sites, each author has collected data as a part of longer-term research projects. In this paper presentation we compare and contrast these data sets, attending to significant intersections and juxtaposing issues of culture and globalization. Within this mode of inquiry we value the particularity of the individual contexts, and locate them alongside one another in a larger bricolage (Johnson, 2010).
We examined observational data, documents and artifacts using Freebody and Luke's (1990) four resources model and the further adaptions of this model (see e.g. Luke & Freebody, 1999) to understand how touch screen devices are being used and positioned as literacy tools. We have engaged in collaborative data analysis, often working 'together' using digital tools ourselves to enable collective conversations. For example, we have used Facetime on iPads and laptops, Skype and email to facilitate collective analyses. We applied iterative and recursive analyses to uncover reoccurring themes both within and across sites and artifacts.
As our paper will elaborate, mobile touch screen devices such as iPads are widely being taken up in educational settings, and regarded as having the possibility to shift teaching and learning in new directions, as "paradigm breakers" (p. 4, Gov't of AB, 2011). As personal, mobile devices, these tools present challenges that require educators to think differently about learning and teaching. Our paper also addresses the opportunities and affordances that iPads might offer to learners, as having the potential for students to engage in playful exploration, and in the role of designers, creators, and producers, rather than as passive recipients.

Disparities in pediatric leukemia early survival in Argentina: a population-based study

To identify disparities-using recursive partitioning (RP)-in early survival for children with leukemias treated in Argentina, and to depict the main characteristics of the most vulnerable groups.

Continuous finite-time state feedback stabilizers for some nonlinear stochastic systems

This paper is concerned with the problem of finite-time stabilization for some nonlinear stochastic systems. Based on the stochastic Lyapunov theorem on finite-time stability that has been established by the authors in the paper, it is proven that Euler-type stochastic nonlinear systems can be finite-time stabilized via a family of continuous feedback controllers. Using the technique of adding a power integrator, a continuous, global state feedback controller is constructed to stabilize in finite time a large class of two-dimensional lower-triangular stochastic nonlinear systems. Also, for a class of three-dimensional lower-triangular stochastic nonlinear systems, a recursive design scheme of finite-time stabilization is given by developing the technique of adding a power integrator and constructing a continuous feedback controller. Finally, a simulation example is given to illustrate the theoretical results. © 2014 John Wiley & Sons, Ltd.

Least squares learning and the US Treasury bill rate

Understanding how agents formulate their expectations about Fed behavior is important for market participants because they can potentially use this information to make more accurate estimates of stock and bond prices. Although it is commonly assumed that agents learn over time, there is scant empirical evidence in support of this assumption. Thus, in this paper we test if the forecast of the three month T-bill rate in the Survey of Professional Forecasters (SPF) is consistent with least squares learning when there are discrete shifts in monetary policy. We first derive the mean, variance and autocovariances of the forecast errors from a recursive least squares learning algorithm when there are breaks in the structure of the model. We then apply the Bai and Perron (1998) test for structural change to a forecasting model for the three month T-bill rate in order to identify changes in monetary policy. Having identified the policy regimes, we then estimate the implied biases in the interest rate forecasts within each regime. We find that when the forecast errors from the SPF are corrected for the biases due to shifts in policy, the forecasts are consistent with least squares learning. © 2014 Elsevier B.V.

Improved robust Kalman filtering for uncertain systems with missing measurements

In this paper, a novel robust finite-horizon Kalman filter is developed for discrete linear time-varying systems with missing measurements and normbounded parameter uncertainties. The missing measurements are modelled by a Bernoulli distributed sequence and the system parameter uncertainties are in the state and output matrices. A two stage recursive structure is considered for the Kalman filter and its parameters are determined guaranteeing that the covariances of the state estimation errorsare not more than the known upper bound. Finally, simulation results are presented to illustrate the outperformance of the proposed robust estimator compared with the previous results in the literature.

A new algorithm to design minimal multi-functional observers for linear systems

Designing minimum possible order (minimal) observers for Multi-Input Multi-Output (MIMO) linear systems have always been an interesting subject. In this paper, a new methodology to design minimal multi-functional observers for Linear Time-Invariant (LTI) systems is proposed. The approach is applicable, and it also helps in regulating the convergence rate of the observed functions. It is assumed that the system is functional observable or functional detectable, which is less conservative than assuming the observability or detectability of the system. To satisfy the minimality of the observer, a recursive algorithm is provided that increases the order of the observer by appending the minimum required auxiliary functions to the desired functions that are going to be estimated. The algorithm increases the number of functions such that the necessary and sufficient conditions for the existence of a functional observer are satisfied. Moreover, a new methodology to solve the observer design interconnected equations is elaborated. Our new algorithm has advantages with regard to the other available methods in designing minimal order functional observers. Specifically, it is compared with the most common schemes, which are transformation based. Using numerical examples it is shown that under special circumstances, the conventional methods have some drawbacks. The problem partly lies in the lack of sufficient numerical degrees of freedom proposed by the conventional methods. It is shown that our proposed algorithm can resolve this issue. A recursive algorithm is also proposed to summarize the observer design procedure. Several numerical examples and simulation results illustrate the efficacy, superiority and different aspects of the theoretical findings.

Corrigendum to “Least squares learning and the US treasury bill rate” [Econ. Syst. 38 (2014) 194–204]

Understanding how agents formulate their expectations about Fed behavior is important for market participants because they can potentially use this information to make more accurate estimates of stock and bond prices. Although it is commonly assumed that agents learn over time, there is scant empirical evidence in support of this assumption. Thus, in this paper we test if the forecast of the three month T-bill rate in the Survey of Professional Forecasters (SPF) is consistent with least squares learning when there are discrete shifts in monetary policy. We first derive the mean, variance and autocovariances of the forecast errors from a recursive least squares learning algorithm when there are breaks in the structure of the model. We then apply the Bai and Perron (1998) test for structural change to a forecasting model for the three month T-bill rate in order to identify changes in monetary policy. Having identified the policy regimes, we then estimate the implied biases in the interest rate forecasts within each regime. We find that when the forecast errors from the SPF are corrected for the biases due to shifts in policy, the forecasts are consistent with least squares learning.

Global finite-time stabilisation for a class of stochastic nonlinear systems by output feedback

In this paper, the problem of global finite-time stabilisation by output feedback is considered for a class of stochastic nonlinear systems. First, based on homogeneous systems theory and the adding a power integrator technique, a homogeneous reduced order observer and control law are constructed in a recursive manner for the nominal system. Then, the homogeneous domination approach is used to deal with the nonlinearities in drift and diffusion terms; it is shown that the proposed output-feedback control law can guarantee that the closed-loop system is global finite-time stable in probability. Finally, simulation examples are carried out to demonstrate the effectiveness of the proposed control scheme.