139,933 research outputs found
SPARKPLUS for Self- and Peer Assessment on Group-Based Honours’ Research Projects
This paper explores an application of an online tool SPARKPLUS (Self and Peer Assessment Resource Kit) for the self and peer assessment on the group-based Honours’ research projects. The Honours’ research projects in School of Civil, Environmental Engineering at University of Adelaide are running in a small group of students (typically four students or less) working with an academic supervisor in a selected area for one year. Since the research project is self-directed study, it is very difficult to fairly assess the contribution of individual students to the group-based research project. The paper-based method of self and peer assessment for the Honour’s research projects was used in the previous years. The same mark was often distributed and no feedback was given. Both the students and academic staff were not satisfied with the paper-based method of self and peer assessment. Thus an online tool SPARK PLUS together with a set of assessment criteria was used for the self and peer assessment of the Honours’ research projects in 2010. Thirty-seven groups participated in the self and peer assessment of using SPARK PLUS in semester one 2010 and a series of results from the online self and peer assessment were obtained and analysed. Feedback sessions were held and substantial feedback was received from students. Based on the feedback, suggestions were made on improving use of the online tool for self and peer assessment on the Honours’ research project.Chengqing Wu, Emmanuel Chanda and John Willisonhttp://www.adelaide.edu.au/erg
Optimal boundary control of a simplified Ericksen--Leslie system for nematic liquid crystal flows in
In this paper, we investigate an optimal boundary control problem for a two
dimensional simplified Ericksen--Leslie system modelling the incompressible
nematic liquid crystal flows. The hydrodynamic system consists of the
Navier--Stokes equations for the fluid velocity coupled with a convective
Ginzburg--Landau type equation for the averaged molecular orientation. The
fluid velocity is assumed to satisfy a no-slip boundary condition, while the
molecular orientation is subject to a time-dependent Dirichlet boundary
condition that corresponds to the strong anchoring condition for liquid
crystals. We first establish the existence of optimal boundary controls. Then
we show that the control-to-state operator is Fr\'echet differentiable between
appropriate Banach spaces and derive first-order necessary optimality
conditions in terms of a variational inequality involving the adjoint state
variables
Searching for rewards in graph-structured spaces
How do people generalize and explore structured spaces? We study human behavior on a multi-armed bandit task, where rewards are influenced by the connectivity structure of a graph. A detailed predictive model comparison shows that a Gaussian Process regression model using a diffusion kernel is able to best describe participant choices, and also predict judgments about expected reward and confidence. This model unifies psychological models of function learning with the Successor Representation used in reinforcement learning, thereby building a bridge between different models of generalization
Method and apparatus for contour mapping using synthetic aperture radar
By using two SAR antennas spaced a known distance, B, and oriented at substantially the same look angle to illuminate the same target area, pixel data from the two antennas may be compared in phase to determine a difference delta phi from which a slant angle theta is determined for each pixel point from an equation Delta phi = (2 pi B/lambda)sin(theta - alpha), where lambda is the radar wavelength and alpha is the roll angle of the aircraft. The height, h, of each pixel point from the aircraft is determined from the equation h = R cos theta, and from the known altitude, a, of the aircraft above sea level, the altitude (elevation), a', of each point is determined from the difference a - h. This elevation data may be displayed with the SAR image by, for example, quantizing the elevation at increments of 100 feet starting at sea level, and color coding pixels of the same quantized elevation. The distance, d, of each pixel from the ground track of the aircraft used for the display may be determined more accurately from the equation d = R sin theta
Electrochemical Studies of Redox Systems for Energy Storage
Particular attention was paid to the Cr(II)/Cr(III) redox couple in aqueous solutions in the presence of Cl(-) ions. The aim of this research has been to unravel the electrode kinetics of this redox couple and the effect of Cl(1) and electrode substrate. Gold and silver were studied as electrodes and the results show distinctive differences; this is probably due to the role Cl(-) ion may play as a mediator in the reaction and the difference in state of electrical charge on these two metals (difference in the potential of zero charge, pzc). The competition of hydrogen evolution with CrCl3 reduction on these surfaces was studied by means of the rotating ring disk electrode (RRDE). The ring downstream measures the flux of chromous ions from the disk and therefore separation of both Cr(III) and H2 generation can be achieved by analyzing ring and disk currents. The conditions for the quantitative detection of Cr(2+) at the ring electrode were established. Underpotential deposition of Pb on Ag and its effect on the electrokinetics of Cr(II)/Cr(III) reaction was studied
Economic and environmental analysis of the introduction of legumes in livestock farming systems
Legumes in low input systems are becoming increasingly important. The socioeconomic implication of the adoption of novel legumes species has been assessed in sheep and dairy cattle grazing systems in Europe using a biological model which has been linked to linear programming models. In the economic sub-model, the mathematical programming models produce an economic evaluation of the legumes in a farming system context, emphasising the land allocation and the availability of nutrients during the different seasons of the production cycle. Then the paper evaluates the impact of adopting the legumes on the regional income and production. In the UK and Germany, the introduction of legumes results in sizeable gains for the farmers whereas in Italy and France the gains are smaller
An interim reference model for the variability of the middle atmosphere H2O vapor distribution
Water vapor is an important minor constituent in the studies of the middle atmosphere for a variety of reasons, including its role as a source for active HO(y) chemicals and its use in analysis of transport processes. A number of in situ and remote techniques were employed in the determination of water vapor distributions. Two of the more complete data sets were used to develop an interim reference profile. First, there are the seven months of Nimbus 7 limb infrared monitor of the stratosphere (LIMS) data obtained during Nov. 1978 to May 1979 over the range 64S to 84N latitude and from about 100 to 1 mb in the mid-mesosphere at several fixed Northern Hemisphere mid-latitude sites. These two data sets were combined to give a mid-lattitude, interim reference water vapor profile for the entire vertical range of the middle atmosphere and with accuracies of better than 25 percent. The daily variability of stratospheric water vapor profiles about the monthly mean was also established from these data sets for selected months. Information is also provided on the longitudinal variability of LIMS water vapor profiles about the daily, weekly, and monthly zonal means. Generally, the interim reference water vapor profile and its variability are consistent with prevailing ideas about chemistry and transport
The effect of supernova heating on cluster properties and constraints on galaxy formation models
Models of galaxy formation should be able to predict the properties of
clusters of galaxies, in particular their gas fractions, metallicities, X-ray
luminosity-temperature relation, temperature function and mass-deposition-rate
function. Fitting these properties places important constaints on galaxy
formation on all scales. By following gas processes in detail, our
semi-analytic model (based on that of Nulsen & Fabian 1997) is the only such
model able to predict all of the above cluster properties. We use realistic gas
fractions and gas density profiles, and as required by observations we break
the self-similarity of cluster structure by including supernova heating of
intracluster gas, the amount of which is indicated by the observed
metallicities. We also highlight the importance of the mass-deposition-rate
function as an independent and very sensitive probe of cluster structure.Comment: 5 pages, 4 figures, accepted for publication in MNRAS as a lette
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