A novel sampling theorem on the rotation group

We develop a novel sampling theorem for functions defined on the three-dimensional rotation group SO(3) by connecting the rotation group to the three-torus through a periodic extension. Our sampling theorem requires $4L^3$ samples to capture all of the information content of a signal band-limited at $L$, reducing the number of required samples by a factor of two compared to other equiangular sampling theorems. We present fast algorithms to compute the associated Fourier transform on the rotation group, the so-called Wigner transform, which scale as $O(L^4)$, compared to the naive scaling of $O(L^6)$. For the common case of a low directional band-limit $N$, complexity is reduced to $O(N L^3)$. Our fast algorithms will be of direct use in speeding up the computation of directional wavelet transforms on the sphere. We make our SO3 code implementing these algorithms publicly available.Comment: 5 pages, 2 figures, minor changes to match version accepted for publication. Code available at http://www.sothree.or

Exploring the Relationship between Urban Form, Mobility and Social Well-Being: Towards an Interdisciplinary Field of Sustainable Urban Planning and Transport Development

This Special Issue focuses on exploring the relationship between urban form, mobility, and social well-being across neighbourhoods, cities, and regions. Understanding more about these relationships is helpful in shaping integrated sustainable urban planning and transport development strategies. There is a growing body of research examining changes in well-being in response to social and spatial interventions (e.g., inequality, social exclusion, the built environment, land use, and transport development) and behavioural changes (e.g., travel preferences). However, there is a lack of understanding of the different types of well-being (e.g., social, hedonic, eudaimonic, short-term/long-term, or individual/collective well-being, as well as the spatial nature of well-being) and the variations in their impact. Furthermore, limited attention has been paid to the standardised measurement of well-being in both quantitative and qualitative terms in the field of social sciences, particularly regarding social and eudaimonic well-being, since they are abstract concepts and thus difficult to assess accurately. Therefore, there is an urgent need to further explore the relationship between urban form, mobility, and social well-being, as well as to examine the ways in which different types of well-being can be measured by applying various advanced models and research approaches within the broad field of urban planning and transport

Marker für die Zulassung von Maispopulationssorten

The genetic resource of adapted German maize landraces is threatened to get lost. Unsolved admission standards at the Federal Office for Plant Varieties are a main obstacle for breeders to use such material. Until now each application for admission has been rejected due to missing homogeneity. Therefore, population specific marker alleles should be developed and deposited at the Federal Office for Plant Varieties as further selection criteria. A first step is the development of markers for phenotypic apparent traits. We developed three markers for red and white cob glume color and used them for selection of two maize populations. The next step would be the development of non-genic markers. Although these markers have no phenotypic effects they also do not influence yield or other physiological important traits

Polaronic effects in strongly coupled electron-phonon systems: Exact diagonalization results for the 2D Holstein t-J model

Ground-state and dynamical properties of the 2D Holstein t-J model are examined by means of direct Lanczos diagonalization, using a truncation method of the phononic Hilbert space. The single-hole spectral function shows the formation of a narrow hole-polaron band as the electron-phonon coupling increases, where the polaronic band collapse is favoured by strong Coulomb correlations. In the two-hole sector, the hole-hole correlations unambiguously indicate the existence of inter-site bipolaronic states. At quarter-filling, a polaronic superlattice is formed in the adiabatic strong-coupling regime.Comment: 3 pages, LaTeX, 6 Postscript figures, Proc. Int. Conf. on Strongly Correlated Electron Systems, Zuerich, August 1996, accepted for publication in Physica

Exploratory shopping: attention affects in-store exploration and unplanned purchasing

A fundamental function of retailing is to bring products into the view of shoppers, because viewing products can activate forgotten or new needs. Retailers thus employ various strategies to entice shoppers to explore the product assortment and store environment, in the hopes of stimulating unplanned purchasing. Here we investigate consumers’ breadth of attention as a mechanism of such in-store exploration and hence of unplanned purchasing. Specifically, attentional breadth is the focus that is directed to a wider or more limited area in processing visual scenes. In a series of lab and field experiments we show that shoppers’ attentional breadth activates an exploratory mindset that stimulates visual and physical exploration of shopping environments, ultimately affecting their product choices and unplanned purchasing. We also show that more impulsive buyers are more susceptible to these effects. These results complement and constrain prior theorizing on mindset theory, attention, store exploration, and unplanned purchasing, all of which are of practical importance to both retailers and consumers

Entwicklung von Populationen bei Mais (Zea mays L.) Selektionseffizienz und Leistungsfähigkeit

Maize is one of the most important crops around the world. Global players in seed production offer more than hundreds of different varieties. All of them are hybrids whereas open pollinated varieties (OPVs) are rare or extinct. In Germany (and many other European countries) no new OPVs are registered; efforts to do so failed in the past. The main advantage of OPVs is their phenotypic and genetic heterogeneity and thus their ability to adapt to different environmental conditions. This could be of utmost interest facing the complex challenge of climate change. Populations based on new breeding material were developed and tested in comparison to actual hybrids and landraces. While the new populations achieved about 80 % of the hybrid yield, landraces failed with only 65 %. The efficiency of selection methods needs to be improved

Expressing Measurement Uncertainty in OCL/UML Datatypes

Uncertainty is an inherent property of any measure or estimation performed in any physical setting, and therefore it needs to be considered when modeling systems that manage real data. Although several modeling languages permit the representation of measurement uncertainty for describing certain system attributes, these aspects are not normally incorporated into their type systems. Thus, operating with uncertain values and propagating uncertainty are normally cumbersome processes, di cult to achieve at the model level. This paper proposes an extension of OCL and UML datatypes to incorporate data uncertainty coming from physical measurements or user estimations into the models, along with the set of operations de ned for the values of these types.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Stable Magnetostatic Solitons in Yttrium Iron Garnet Film Waveguides for Tilted in-Plane Magnetic Fields

The possibility of nonlinear pulses generation in Yttrium Iron Garnet thin films for arbitrary direction between waveguide and applied static in-plane magnetic field is considered. Up to now only the cases of in-plane magnetic fields either perpendicular or parallel to waveguide direction have been studied both experimentally and theoretically. In the present paper it is shown that also for other angles (besides 0 or 90 degrees) between a waveguide and static in-plane magnetic field the stable bright or dark (depending on magnitude of magnetic field) solitons could be created.Comment: Phys. Rev. B (accepted, April 1, 2002