Search results for "J81"
showing 5 items of 5 documents
Bhabha Scattering and a special pencil of K3 surfaces
2018
We study a pencil of K3 surfaces that appeared in the $2$-loop diagrams in Bhabha scattering. By analysing in detail the Picard lattice of the general and special members of the pencil, we identify the pencil with the celebrated Ap\'ery--Fermi pencil, that was related to Ap\'ery's proof of the irrationality of $\zeta(3)$ through the work of F. Beukers, C. Peters and J. Stienstra. The same pencil appears miraculously in different and seemingly unrelated physical contexts.
Arithmetic and geometry of a K3 surface emerging from virtual corrections to Drell--Yan scattering
2019
We study a K3 surface, which appears in the two-loop mixed electroweak-quantum chromodynamic virtual corrections to Drell--Yan scattering. A detailed analysis of the geometric Picard lattice is presented, computing its rank and discriminant in two independent ways: first using explicit divisors on the surface and then using an explicit elliptic fibration. We also study in detail the elliptic fibrations of the surface and use them to provide an explicit Shioda--Inose structure. Moreover, we point out the physical relevance of our results.
Ergonomics Awareness and Employee Performance: An Exploratory Study
2017
The study examined the effects of ergonomics on employee performance by ascertaining the level of ergonomics awareness in Nigerian organizations, identifying the factors hindering the use of ergonomic, and the best practices and methods adopted by various organizations across industries. Despite a knowledge of importance to a growing number of researchers in Nigeria, there is still a dearth in knowledge of ergonomics design and its implementation in Nigeria. This can be observed in the low level of its adoption. The study adopted an exploratory approach through the review of literature. It was seen that several factors have hindered the efficient implementation of ergonomics in Nigeria whic…
More hours, more jobs? The employment effects of longer working hours
2014
Increases in standard hours of work have been a contentious policy issue in Germany. Whilst this might directly lead to a substitution of workers by hours, there may also be a positive employment effect due to reduced costs. Moreover, the response of firms may differ between firms that offer overtime and those that do not. For a panel of German plants (2001–2006) drawn from the IAB Establishment Panel, we are the first to analyse the effect of increased standard hours on employment. Using difference-in-difference methods we find that, consistent with theory, overtime plants showed a significant positive employment response, whilst for standard-time plants there is no difference between plan…
Gestión empresarial y dinámica laboral en España
2015
El objetivo del presente artículo es plantear una serie de reflexiones sobre la dinámica labo- ral reciente en la economía española bajo el enfoque analítico de la segmentación laboral. Desde esta perspectiva, la situación y problemas del mercado laboral se explican por un conjunto de factores relacionados con las prácticas de gestión empresarial y no tanto por la regulación que limita la competencia en el mercado o las modalidades contractuales. Nues- tra conclusión es que es necesario superar el marco analítico restringido del enfoque econó- mico convencional e introducir otras dimensiones, que van más allá del mercado, para una mejor compresión de los problemas laborales. En este sentido…