12,218 research outputs found
The potential role of ePortfolios in the Teaching Excellence Framework
Current debates on HE policy in the UK are dominated by the evolving Teaching Excellence Framework (TEF) which will soon involve the government establishing key metrics.  In this context, and seizing this valuable moment in policy formation, we here provide a brief foray into the multiple aspects of âteaching excellenceâ (TE) as a basis to highlight both the complexity of identifying ways to measure it and the shortcomings of existing official developments. In the absence of a clear conceptual understanding of the learning processes and the role of teaching which apparently underpins the TEF, we present a model of the learning process to which the indicators currently proposed by the authorities can be related. We propose that ePortfolios can play a special role in the TEF in capturing the qualitative outcomes of learning processes which, importantly, reflect the student perspective in terms of goals, learning experiences and achievement. These are both crucial yet missing elements of the proposals to date. Finally, we provide some examples of how information from ePortfolios could be used by HE institutions to enhance their institutional submissions to the TEF.
Gauge-Higgs unification with brane kinetic terms
By identifying the Higgs field as an internal component of a higher
dimensional gauge field it is possible to solve the little hierarchy problem.
The construction of a realistic model that incorporates such a gauge-Higgs
unification is an important problem that demands attention. In fact, several
attempts in this direction have already been put forward. In this letter we
single out one such attempt, a 6D SU(3) extended electroweak theory, where it
is possible to obtain a Higgs mass prediction in accord with global fits. One
shortcoming of the model is its prediction for the Weinberg angle, it is too
large. We slightly modify the model by including brane kinetic terms in a way
motivated by the orbifold action on the 6D fields. We show that in this way it
is possible to obtain the correct Weinberg angle while keeping the desired
results in the Higgs sector.Comment: 11 pages, 2 figures. References added. Version to appear in Phys.
Lett.
A mathematical optimisation model of a New Zealand dairy farm: The integrated dairy enterprise (IDEA) framework
Optimisation models are a key tool for the analysis of emerging policies, price sets, and technologies within grazing systems. A detailed nonlinear optimisation model of a New Zealand dairy farming system is described. The framework is notable for its rich portrayal of pasture and cow biology that add substantial descriptive power to standard approaches. Key processes incorporated in the model include: (1) pasture growth and digestibility that differ with residual pasture mass and rotation length, (2) pasture utilisation that varies by stocking rate, and (3) different levels of intake regulation. Model output is shown to closely match data from a more detailed simulation model (deviations between 0 and 5 per cent) and survey data (deviations between 1 and 11 per cent), providing confidence in its predictive capacity. Use of the model is demonstrated in an empirical application investigating the relative profitability of production systems involving different amounts of imported feed under price variation. The case study indicates superior profitability associated with the use of a moderate level of imported supplement, with Operating Profit ($NZ ha-1) of 934, 926, 1186, 1314, and 1093 when imported feed makes up 0, 5, 10, 20 and 30 per cent of the diet, respectively. Stocking rate and milk production per cow increase by 35 and 29 per cent, respectively, as the proportion of imported feed increases from 0 to 30 per cent of the diet. Pasture utilisation increases with stocking rate. Accordingly, pasture eaten and nitrogen fertiliser application increase by 20 and 213 per cent, respectively, as the proportion of imported feed increases from 0 to 30 per cent of the diet
CP violating phase from charged-lepton mixing
A model independent analysis of the leptonic Dirac CP-violating phase
({\delta}) is presented. The analysis uses the experimentally determined values
of the mixing angles in the lepton mixing matrix in order to explore the
allowed values for {\delta} and possible general forms for the charged lepton
mixing matrix. This is done under two general assumptions: 1) that the mixing
matrix in the neutrino sector is the so-called tribimaximal matrix and hence
the non zero value for {\theta}13 arises due to the mixing matrix in the
charged lepton sector and 2) the charged lepton mixing matrix is parametrized
in terms of three angles and one phase. It is found that any value of {\delta}
is still consistent with the data and that, considering the assumptions above,
regardless of the value for {\delta}, the 1-3 mixing angle in the charged
lepton sector is small but non zero and the 2-3 mixing angle can take values in
only two possible small ranges around 0 and {\pi}/2 respectively.Comment: References adde
TeV scale Dark Matter and electroweak radiative corrections
Recent anomalies in cosmic rays data, namely from the PAMELA collaboration,
can be interpreted in terms of TeV scale decaying/annihilating Dark Matter. We
analyze the impact of radiative corrections coming from the electroweak sector
of the Standard Model on the spectrum of the final products at the interaction
point. As an example, we consider virtual one loop corrections and real gauge
bosons emission in the case of a very heavy vector boson annihilating into
fermions. We show that the effect of electroweak corrections is relevant, but
not as big as sometimes claimed in the literature. At such high scales, one
loop electroweak effects are so big that eventually higher orders/resummations
have to be considered: we advocate for the inclusion of these effects in parton
shower Montecarlos aiming at the description of TeV scale physics.Comment: Comments added, published versio
Asymptotic behavior and zero distribution of polynomials orthogonal with respect to Bessel functions
We consider polynomials P_n orthogonal with respect to the weight J_? on [0,?), where J_? is the Bessel function of order ?. Asheim and Huybrechs considered these polynomials in connection with complex Gaussian quadrature for oscillatory integrals. They observed that the zeros are complex and accumulate as n?? near the vertical line Rez=??2. We prove this fact for the case 0???1/2 from strong asymptotic formulas that we derive for the polynomials Pn in the complex plane. Our main tool is the Riemann-Hilbert problem for orthogonal polynomials, suitably modified to cover the present situation, and the Deift-Zhou steepest descent method. A major part of the work is devoted to the construction of a local parametrix at the origin, for which we give an existence proof that only works for ??1/2
A Model of Neutrino and Higgs Physics at the Electroweak Scale
We present and explore the Higgs physics of a model that in addition to the
Standard Model fields includes a lepton number violating singlet scalar field.
Based on the fact that the only experimental data we have so far for physics
beyond the Standard Model is that of neutrino physics, we impose a constraint
for any addition not to introduce new higher scales. As such, we introduce
right-handed neutrinos with an Electroweak Scale mass. We study the Higgs decay
and show that it leads to different signatures compared to
those in the Standard Model, making it possible to detect them and to probe the
nature of their couplings.Comment: 11 pages, 4 figures, 1 table. Corrected factor on eq. 17 and data
table I. Added references. Version to appear in Physics Letters
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