On relating functional modeling approaches: abstracting functional models from behavioral models

This paper presents a survey of functional modeling approaches and describes a strategy to establish functional knowledge exchange between them. This survey is focused on a comparison of function meanings and representations. It is argued that functions represented as input-output flow transformations correspond to behaviors in the approaches that characterize functions as intended behaviors. Based on this result a strategy is presented to relate the different meanings of function between the approaches, establishing functional knowledge exchange between them. It is shown that this strategy is able to preserve more functional information than the functional knowledge exchange methodology of Kitamura, Mizoguchi, and co-workers. The strategy proposed here consists of two steps. In step one, operation-on-flow functions are translated into behaviors. In step two, intended behavior functions are derived from behaviors. The two-step strategy and its benefits are demonstrated by relating functional models of a power screwdriver between methodologies

Incommensurability and rationality in engineering design: the case of functional decomposition

In engineering design research different models of functional decomposition are advanced side-by-side. In this paper I explain and validate this co-existence of models in terms of the Kuhnian thesis of methodological incommensurability. I advance this analysis in terms of the thesis’ construal of (non-algorithmic) theory choice in terms of values, expanding this notion to the engineering domain. I further argue that the (by some) implicated threat of the thesis to rational theory choice has no force in the functional decomposition case: co-existence of different models of functional decomposition is rational from an instrumental point of view. My explanation covers cases in which different models are advanced as means for the same objective. Such cases cannot be explicated with the explanatory construct of variety in objectives, as advanced in other analyses of co-existing conceptualizations in engineering

A non-Archimedean approach to prolongation theory

Some evolution equations possess infinite-dimensional prolongation Lie algebras which can be made finite-dimensional by using a bigger (non-Archimedean) field. The advantage of this is that convergence problems hardly exist in such a field. Besides that, the accompanying Lie groups can be easily constructed

The explicit form of the Lie algebra of Wahlquist and Estabrook. A presentation problem

The structure of the KdV-Lie algebra of Wahlquist and Estabrook is made explicit. This is done with help of a table of Lie-products and an inherent grading of the algebra

Public sector managers of human services : their challenges and strategies : a thesis presented in partial fulfilment of the requirements for the degree of Master of Social Work at Massey University, Manawatu, New Zealand

Middle managers of human services in the public sector have a unique role that allows them to be part of the lives of clients and their families by implementing the strategic vision of political leaders. The expectations of middle managers can be complex and contradictory and therefore challenging. This research identifies the challenges middle managers of human services in the public sector encounter and the strategies that they have developed to deal with these. The support that senior managers in public sector organisations can offer to their middle managers in this process is also discussed. The study is qualitative and placed in a post-modernist position and social constructive perspective. Data is collected through the use of semi-structured interviews and examined using an interpretative thematic approach. The analysis identified a range of challenges for middle managers in the public sector and strategies these managers use to deal with them. Interestingly a number of identified challenges are also identified as a strategy depending on the support middle managers receive from the senior managers in their organisation. The findings identify that a strong strategic vision needs to be in place in public sector organisations to develop clear roles and responsibilities for middle managers with allocated resources. Middle managers need access to training, supervision and networking to deal with additional challenges such as changes in funding and information management. Recommendations are made to public sector organisations to support the development of effective strategies to deal with the challenges identified by their middle managers. Recommendations are made to middle managers in the public sector to prioritise and advocate for their own needs and requirements as they do for their clients and their staff. This research will support both senior and middle managers in public sector organisations in finding strategies to support middle managers to fulfil their role effectively

The Power of Low Frequencies: Faraday Tomography in the sub-GHz regime

Faraday tomography, the study of the distribution of extended polarized emission by strength of Faraday rotation, is a powerful tool for studying magnetic fields in the interstellar medium of our Galaxy and nearby galaxies. The strong frequency dependence of Faraday rotation results in very different observational strengths and limitations for different frequency regimes. I discuss the role these effects take in Faraday tomography below 1 GHz, emphasizing the 100-200 MHz band observed by the Low Frequency Array and the Murchison Widefield Array. With that theoretical context, I review recent Faraday tomography results in this frequency regime, and discuss expectations for future observations.Comment: 12 pages, 4 figures. Accepted for publication in Galaxies as part of the special issue "The Power of Faraday Tomography

Social Democracy and the “Developmental State” as Development Alternatives for South Africa

This paper investigates social democracy and the “developmental state” model as development alternatives for South Africa. This research is significant as it enhances the developmental debate in South Africa that is indispensable in light of South Africa’s poor socio-economic performance. A comparative-historical study is conducted, as well as an analysis of the socio-political situation in South Africa to determine each model’s compatibility with South Africa. State autonomy is assumed essential. Liberal democracy and the authoritarian “developmental state” model are rejected on theoretical and compatibility grounds. Social democracy is therefore investigated. It is concluded that this model is theoretically stronger, yet ideologically squeezed, and its execution is hindered by major stumbling blocks that are identified. Ultimately, it is shown that the economics is fairly simple, but the “primacy of politics” is essential.Social democracy, developmental state, South Africa, Political Economy, Public Economics,

The Henize sample of S stars: IV. New symbiotic stars

The properties of the few symbiotic stars detected among the 66 binary S stars from the Henize sample are discussed. Two stars (Hen 18 and Hen 121) exhibit both a strong blue-violet continuum and strong H_alpha emission (FWHM of 70 km/s), whereas Hen 134 and 137 exhibit weak H_alpha emission. The H_alpha profiles are typical of non-dusty symbiotic stars belonging to class S-3 as defined by Van Winckel et al. (1993, A&AS 102, 401). In that class as in the Henize symbiotic S stars, He I, [N II] or [S II] emission lines are absent, suggesting that the nebular density is high but the excitation rather low. The radial velocity of the centre of the H_alpha emission is identical to that of the companion star (at least for Hen 121 where this can be checked from the available orbital elements), thus suggesting that the H_alpha emission originates from gas moving with the companion star. For Hen 121, this is further confirmed by the disappearance of the ultraviolet Balmer continuum when the companion is eclipsed by the S star. Hen 121 is thus the second eclipsing binary star discovered among extrinsic S stars (the first one is HD 35155). A comparison of the available data on orbital periods and H_alpha emission leads to the conclusion that H_alpha emission in S stars seems to be restricted to binary systems with periods in the range 600 - 1000 d, in agreement with the situation prevailing for red symbiotic stars (excluding symbiotic novae). Symbiotic S stars are found among the most evolved extrinsic S stars.Comment: 10 pages, 9 figures, accepted for publication in Astronomy and Astrophysic

IT Project Management from a Systems Thinking Perspective: A Position Paper

We proposes a Systems Thinking approach to the study of IT project management and show how this approach helps project managers in controlling their projects. To illustrate our proposal, we present an example model of the dynamics of IT out-sourcing projects. The example model explains these dynamics in terms of feedback loops consisting of causal relations re-ported in the literature. The model provides insight in how coordination, trust, information exchange and possibilities for op-portunistic behaviour influence each other and together influence delivery quality, which in turn influences trust. The integra-tion of these insights provided by applying the Systems Thinking perspective helps project managers to reason about how their choices influence project outcome. The Systems Thinking perspective can serve as an additional tool in the academic study of IT project management. Applying the Systems Thinking perspective also calls for additional research in which this perspective is itself the object of study

Cosmic abundances: The impact of stellar duplicity

The mass-transfer scenario links chemical peculiarities with stellar duplicity for an increasing number of stellar classes (classical and dwarf barium stars, subgiant and giant CH stars, S stars without technetium, yellow symbiotic stars, WIRRING stars, Abell-35-like nuclei of planetary nebulae...). Despite these successes, the mass-transfer scenario still faces several problems: What is the mass-transfer mode? Why orbital elements of dwarf barium stars do not fully match those of the classical barium stars? What is the origin of the few non-binary stars among dwarf barium stars? The paper reviews these open questions.Comment: 14 pages, 4 figures, to appear in `Cosmic Abundances as Records of Stellar Evolution and Nucleosynthesis', edited by F.N. Bash, T.G. Barnes, ASP Conf. Ser., in pres