Isophote curves on timelike surfaces in Minkowski 3-space

Isophote comprises a locus of the surface points whose normal vectors make a constant angle with a fixed vector. In this paper, isophote curves are studied on timelike surfaces in Minkowski 3-space E31. The axises of spacelike and timelike isophote curves are found via their Darboux frames. Subsequently, the relationship between isophotes and slant helices is shown on timelike surfaces.Comment: 11 pages. arXiv admin note: text overlap with arXiv:1203.438

Constant Angle Surfaces in Product Spaces

We classify all the surfaces in $M^2(c_1)\times M^2(c_2)$ for which the tangent space $T_pM^2$ makes constant angles with $T_p(M^2(c_1)\times \{p_2\})$ (or equivalently with $T_p(\{p_1\}\times M^2(c_2))$ for every point $p=(p_1,p_2)$ of $M^2$. Here $M^2(c_1)$ and $M^2(c_2)$ are 2-dimensional space forms, not both flat. As a corollary we give a classification of all the totally geodesic surfaces in $M^2(c_1)\times M^2(c_2)$.Comment: 25 pages, revised version: added references, typos correcte

Constant angle surfaces in product spaces.

53B25;

Construction and validation of the self-conscious emotions at work scale

The present study reports on the construction and validation of a new assessment instrument for self-conscious emotions in the work context, namely the Self-Conscious Emotions at Work Scale (SCEWS). In eight typical self-conscious work scenarios respondents have to indicate their emotional reaction in terms of 20 appraisals, subjective experiences, and action tendencies that are relevant and representative for the domain of self-conscious emotions. In total 512 students and 467 working adults completed the SCEWS and reported the frequency of positive emotions, anger, anxiety and sadness. In both samples a three-factorial structure emerged with a guilt, a shame/humiliation, and an anger in self-conscious situations factor. These three self-conscious emotion factors correlated differentially and in a predicted way with the frequency of emotions. Guilt-proneness was predicted to be psychologically constructive and correlated to the frequency of positive emotions. The proneness to shame/humiliation was expected to relate to internalising psychopathological tendencies, and positively correlated to a frequency of anxiety and sadness. Proneness to anger in self-conscious situations was expected to relate to externalising psychopathological tendencies and correlated with the frequency of anger in general. The present study demonstrates that self-conscious emotions can be validly measured in the work context. The new instrument allows for the systematic study of the role of self-conscious emotions in work and organisational behaviour

Weak helix submanifolds of euclidean spaces

It is shown that there exist nonstrong weak 2-helix surfaces of R

Pseudo-parallel Lagrangian submanifolds are semi-parallel

We prove a conjecture formulated by Pablo M. Chacon and Guillermo A. Lobos in [Pseudo-parallel Lagrangian submanifolds in complex space forms, Differential Geom. Appl.] stating that every Lagrangian pseudo-parallel submanifold of a complex space form of dimension at least 3 is semi-parallel

Modelling heterogeneity to estimate the ex ante value of biotechnology innovations

After more than a decade of GM crops, literature reports farmers and consumers can gain significantly from the technology, despite the intellectual property rights assigned to the innovator. In this paper we assess the effect of heterogeneity on this distribution of benefits. A two dimensional framework is created to assess the ex ante benefits of an innovation. Given this setting and the scarce data often available, a parametric modelling approach is taken. The two dimensions of heterogeneity, spatial and temporal, are explicitly modelled as they have a different importance for different technologies. Using this framework we can simulate different corporate pricing strategies and evaluate the benefits generated under changing heterogeneity. The framework is tested on the introduction of HT sugar beet in the EU-27.Heterogeneity, Parametric modelling, ex ante, Research and Development/Tech Change/Emerging Technologies,