Socio-technical requirements for production planning and control systems

Due to increasing customer requirements and intensifying competition, manufacturing companies are facing growing challenges in the successful order handling. As a result, employees are forced to make increasingly complex decisions in the shortest possible time. At this, the tasks of production planning and control (PPC) are particularly affected. In response to the increasing complexity of tasks, companies rely more than ever on the potential of socio-technical systems, rendered possible by the integration of information systems (IS) in the daily decision-making process. However, due to the increasing complexity of systems used, many users are not capable to raise the potential of information systems acquired, which is why the benefits of IS implementation often fall short of expectations. The following paper thus analyses and structures potential decisive factors causing the lack of problem solving capability in context of using PPC systems. Based on findings from acceptance research, socio-technical influencing factors for the targeted handling of information systems are determined. The developed requirement framework is furthermore compared with current IS implementation strategies to derive future research needs

Field evidence for the upwind velocity shift at the crest of low dunes

Wind topographically forced by hills and sand dunes accelerates on the upwind (stoss) slopes and reduces on the downwind (lee) slopes. This secondary wind regime, however, possesses a subtle effect, reported here for the first time from field measurements of near-surface wind velocity over a low dune: the wind velocity close to the surface reaches its maximum upwind of the crest. Our field-measured data show that this upwind phase shift of velocity with respect to topography is found to be in quantitative agreement with the prediction of hydrodynamical linear analysis for turbulent flows with first order closures. This effect, together with sand transport spatial relaxation, is at the origin of the mechanisms of dune initiation, instability and growth.Comment: 13 pages, 6 figures. Version accepted for publication in Boundary-Layer Meteorolog