Visual exploration of eye movement data using the Space-Time-Cube

Eye movement recordings produce large quantities of spatio- temporal data, and are more and more frequently used as an aid to gain further insight into human thinking in usability studies in GIScience domain among others. After reviewing some common visualization methods for eye movement data, the limitations of these methods are discussed. This paper proposes an approach that enables the use of the Space-Time-Cube (STC) for representation of eye movement recordings. Via interactive functions in the STC, spatiotemporal patterns in eye movement data could be analyzed. A case study is presented according to proposed solutions for eye movement data analysis. Finally, the advantages and limitations of using the STC to visually analyze eye movement recordings are summarized and discussed

Quantum properties of two-dimensional electron gas in the inversion layer of Hg1−xCdxTe bicyrstals

The electronic and magnetotransport properties of conduction electrons in the grain boundary interface of p-type Hg1−xCdxTe bicrystals are investigated. The results clearly demonstrate the existence of a two-dimensional degenerate n-type inversion layer in the vicinity of the grain boundary. Hydrostatic pressure up to 103 MPa is used to characterize the properties of the two-dimensional electron gas in the inversion layer. At atmospheric pressure three series of quantum oscillations are revealled, indicating that tthree electric subbands are occupied. From quantum oscilations of the magnetoresistivity the characteristics parameters of the electric subbands (subband populations nsi, subband energies EF−Ei, effective electron masses m*ci) and their pressure dependences are established. A strong decrease of the carrier concentration in the inversion layer and of the corresponding subband population is observed when pressure is applied A simple theoretical model based on the triangular-well approximation and taking into account the pressure dependence of the energy band structure of Hg1−xCdxTe is use to calculate the energy band diagram of the quantum well and the pressure dependence of the subband parameters

21st century fisheries management: a spatio-temporally explicit tariff-based approach combining multiple drivers and incentivising responsible fishing

Abstract Kraak, S. B. M., Reid, D. G., Gerritsen, H. D., Kelly, C. J., Fitzpatrick, M., Codling, E. A., and Rogan, E. 2012. 21st century fisheries management: a spatio-temporally explicit tariff-based approach combining multiple drivers and incentivising responsible fishing. – ICES Journal of Marine Science, 69: 590–601. Traditionally fisheries management has focused on biomass and mortality, expressed annually and across large management units. However, because fish abundance varies at much smaller spatio-temporal scales, fishing mortality can potentially be controlled more effectively if managed at finer scale. The ecosystem approach requires more indicators at finer scales as well. Incorporating ecosystem targets would need additional management tools with potentially conflicting results. We present a simple, integrated, management approach that provides incentives for “good behaviour”. Fishers would be given a number of fishing-impact credits, called real-time incentives (RTIs), to spend according to spatio-temporally varying tariffs per fishing day. RTI quotas and tariffs could be based on commercial stocks and ecosystem targets. Fishers could choose how to spend their RTIs, e.g. by limited fishing in high-catch or sensitive areas or by fishing longer in lower-catch or less sensitive areas. The RTI system does not prescribe and forbid, but instead allows fishers to fish wherever and whenever they want; ecosystem costs are internalized and fishers have to take them into account in their business decisions. We envisage no need for traditional landings or catch quotas for the fleets while operating under the scheme. The approach could facilitate further devolution of responsibility to industry.</jats:p

Cyclotron resonance of the quasi-two-dimensional electron gas at Hg1-xCdxTe grain boundaries

The magnetotransmission of a p-type Hg0.766Cd0.234Te bicrystal containing a single grain boundary with an inversion layer has been investigated in the submillimetre wavelength range. For the first time the cyclotron resonance lines belonging to the various electric subbands of a quasi-two-dimensional carrier system at a grain boundary could be detected. The measured cyclotron masses and the subband densities determined from Shubnikov-de Haas experiments are compared with theoretical predictions and it is found that the data can be explained very well within the framework of a triangular well approximation model which allows for non-parabolic effects

Prediction of daphnid survival after in situ exposure to complex mixtures

We applied a mechanistically based model to predict the effects of complex mixtures as occurring in the field on the survival of Daphnia magna. We validated the model by comparing predicted survival with observed survival of in situ exposed laboratory cultured daphnids to polluted surface waters, in which over 90 chemical contaminants were measured. Using the chemical composition of the surface water at each sampling site, we calculated whether or not any of the individual or shared no effect concentrations were exceeded. If they were, we calculated the effect on survival. In 34 out of 37 cases (92%) we correctly predicted daphnid survival in surface waters. In the case of mortality we could also appoint the compound or group of compounds causing the effect. It is concluded that the proposed mechanistically based model accurately predicts effects on daphnids in the field, given the chemical composition of the water. Hence it is a powerful tool to link the chemical and ecological status of surface waters