7,518 research outputs found
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
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