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Financing SMEs: a model for optimising the capital structure
This paper argues that the existing finance literature is inadequate with respect to its cov-erage of capital structure of small and medium sized enterprises (SMEs). In particular it is argued that the cost of equity (being both conceptually ill defined and empirically non quantifiable) is not applicable to the capital structure decisions for a large proportion of SMEs and the optimal capital structure depends only on the mix of short and long term debt. The paper then presents a model for optimising the debt mix and demonstrates its practical application using an Italian firm’s debt structure as a case study
A holistic approach to the evaluation of sustainable housing
Residential housing is often evaluated against single or at best a limited number of similar criteria. These include quantifiable indicators such as energy use and its associated greenhouse gas emissions. It might also include material consumption from an embodied energy or resource use perspective. Social factors or qualitative indicators may be evaluated but are rarely placed or juxtaposed alongside these quantifiable indicators. A one-dimensional approach will be limiting because sustainable development includes both environmental and social factors. This paper describes the methodologies that have been developed to assess housing developments against five quite different criteria. These are: energy use, resource use, neighbourhood character, neighbourhood connectedness and diversity. In each case, high and low sustainability practice has been identified so that ranking is possible. These methodologies have then been tested by evaluating a typical precinct (approximately 400 m by 400 m) of a 1970-80s housing development in a suburb of Geelong. The rankings of the particular precinct have then been combined in a visual way to assist in the evaluation of the housing in a more holistic way. The results of this evaluation method are presented, along with a discussion of the strengths and weaknesses of the methodologies. The research is the outcome of collaboration by a cross-disciplinary group of academics within Deakin’s School of Architecture and Building
Chiral perturbation theory for electroweak reactions on deuterium
I summarize two recent applications of chiral perturbation theory to
electromagnetic reactions on deuterium: elastic electron-deuteron scattering,
and Compton scattering on deuterium. Both calculations have now been carried
out to three orders in the chiral expansion. The expansion shows good
convergence and is able to reproduce data for q < 600 MeV in e-d and for
omega=55-95 MeV in gamma-d. These results demonstrate that ChiPT can be used to
reliably compute operators and wave functions for low-momentum-transfer
reactions in light nuclear systems.Comment: 10 pages, 6 figures. Write-up of invited talk at INT Workshop on
"Nuclear Forces and the Quantum Many-Body Problem", October 4-8, 200
PIRATE: A Remotely-Operable Telescope Facility for Research and Education
We introduce PIRATE, a new remotely-operable telescope facility for use in
research and education, constructed from 'off-the-shelf' hardware, operated by
The Open University. We focus on the PIRATE Mark 1 operational phase where
PIRATE was equipped with a widely- used 0.35m Schmidt-Cassegrain system (now
replaced with a 0.425m corrected Dall Kirkham astrograph). Situated at the
Observatori Astronomic de Mallorca, PIRATE is currently used to follow up
potential transiting extrasolar planet candidates produced by the SuperWASP
North experiment, as well as to hunt for novae in M31 and other nearby
galaxies. It is operated by a mixture of commercially available software and
proprietary software developed at the Open University. We discuss problems
associated with performing precision time series photometry when using a German
Equatorial Mount, investigating the overall performance of such 'off-the-shelf'
solutions in both research and teaching applications. We conclude that PIRATE
is a cost-effective research facility, and also provides exciting prospects for
undergraduate astronomy. PIRATE has broken new ground in offering practical
astronomy education to distance-learning students in their own homes.Comment: Accepted for publication in PASP. 14 pages, 11 figure
State of the art: iterative CT reconstruction techniques
Owing to recent advances in computing power, iterative reconstruction (IR) algorithms have become a clinically viable option in computed tomographic (CT) imaging. Substantial evidence is accumulating about the advantages of IR algorithms over established analytical methods, such as filtered back projection. IR improves image quality through cyclic image processing. Although all available solutions share the common mechanism of artifact reduction and/or potential for radiation dose savings, chiefly due to image noise suppression, the magnitude of these effects depends on the specific IR algorithm. In the first section of this contribution, the technical bases of IR are briefly reviewed and the currently available algorithms released by the major CT manufacturers are described. In the second part, the current status of their clinical implementation is surveyed. Regardless of the applied IR algorithm, the available evidence attests to the substantial potential of IR algorithms for overcoming traditional limitations in CT imaging
Reaction kinetic model of a proposed plasma membrane two-cycle H(+)-transport system of Chara corallina.
Measuring Molecular, Neutral Atomic, and Warm Ionized Galactic Gas Through X-Ray Absorption
We study the column densities of neutral atomic, molecular, and warm ionized
Galactic gas through their continuous absorption of extragalactic X-ray spectra
at |b| > 25 degrees. For N(H,21cm) < 5x10^20 cm^-2 there is an extremely tight
relationship between N(H,21cm) and the X-ray absorption column, N(xray), with a
mean ratio along 26 lines of sight of N(xray)/N(H,21cm) = 0.972 +- 0.022. This
is significantly less than the anticpated ratio of 1.23, which would occur if
He were half He I and half He II in the warm ionized component. We suggest that
the ionized component out of the plane is highly ionized, with He being mainly
He II and He III. In the limiting case that H is entirely HI, we place an upper
limit on the He abundance in the ISM of He/H <= 0.103.
At column densities N(xray) > 5x10^20 cm^-2, which occurs at our lower
latitudes, the X-ray absorption column N(xray) is nearly double N(H,21cm). This
excess column cannot be due to the warm ionized component, even if He were
entirely He I, so it must be due to a molecular component. This result implies
that for lines of sight out of the plane with |b| ~ 30 degrees, molecular gas
is common and with a column density comprable to N(H,21cm).
This work bears upon the far infrared background, since a warm ionized
component, anticorrelated with N(H,21cm), might produce such a background. Not
only is such an anticorrelation absent, but if the dust is destroyed in the
warm ionized gas, the far infrared background may be slightly larger than that
deduced by Puget et al. (1996).Comment: 1 AASTeX file, 14 PostScript figure files which are linked within the
TeX fil
Public Perception of Who is a Volunteer : An Examination of the Net-cost Approach from a Cross-Cultural Perspective
Volunteers are the cornerstones on which the voluntary sector is predicated. We are accustomed to using this phrase in every aspect of our lives, yet too little systematic work has been carried out to define this term in a rigorous and precise manner. Volunteering is the essence of the scholarly work of numerous academicians around the world, however there are many issues that arise when people report their own volunteering or attempt to define the term volunteer. No clear-cut definition that encompasses all aspects of volunteering exists. Often too many different activities and situations are aggregated into this concept (Cnaan, Handy, & Wadsworth, 1996; Scheier, 1980; Smith, 1995; Tremper, Seidman, & Tufts, 1994; Vineyard, 1993)
The onset of chaos in orbital pilot-wave dynamics
We present the results of a numerical investigation of the emergence of chaos in the orbital dynamics of droplets walking on a vertically vibrating fluid bath and acted upon by one of the three different external forces, specifically, Coriolis, Coulomb, or linear spring forces. As the vibrational forcing of the bath is increased progressively, circular orbits destabilize into wobbling orbits and eventually chaotic trajectories. We demonstrate that the route to chaos depends on the form of the external force. When acted upon by Coriolis or Coulomb forces, the droplet's orbital motion becomes chaotic through a period-doubling cascade. In the presence of a central harmonic potential, the transition to chaos follows a path reminiscent of the Ruelle-Takens-Newhouse scenario
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