Säilörehua eri tuotannonvaiheisiin : Muista katovuoden opetukset

Lehtiartikkeli (rinnakkaistallennusluvan asianumero: 1832/12 05 01 02/2019)201

Ion: Plato’s Defense of Poetry

This reading of Plato's Ion shows that the philosophic action mimed and engendered by the dialogue thoroughly reverses its (and Plato's) often supposed philosophical point, revealing that poetry is just as defensible as philosophy, and only in the same way. It is by Plato's indirections we find true directions out: the war between philosophy and poetry is a hoax on Plato's part, and a mistake on the part of his literalist readers. The dilemma around which the dialogue moves is false, and would have been recognized as such by Plato's contemporaries. Further, it is intrinsically related to a false, but popular, view of language. So the way out of the false dilemma of the dialogue is the way out of the war between philosophy and poetry, and also makes one see what is false about the view of language which makes such war plausible

Counterrotation in magnetocentrifugally driven jets and other winds

Rotation measurement in jets from T Tauri stars is a rather difficult task. Some jets seem to be rotating in a direction opposite to that of the underlying disk, although it is not yet clear if this affects the totality or part of the outflows. On the other hand, Ulysses data also suggest that the solar wind may rotate in two opposite ways between the northern and southern hemispheres. We show that this result is not as surprising as it may seem and that it emerges naturally from the ideal MHD equations. Specifically, counterrotating jets neither contradict the magnetocentrifugal driving of the flow nor prevent extraction of angular momentum from the disk. The demonstration of this result is shown by combining the ideal MHD equations for steady axisymmetric flows. Provided that the jet is decelerated below some given threshold beyond the Alfven surface, the flow will change its direction of rotation locally or globally. Counterrotation is also possible for only some layers of the outflow at specific altitudes along the jet axis. We conclude that the counterrotation of winds or jets with respect to the source, star or disk, is not in contradiction with the magnetocentrifugal driving paradigm. This phenomenon may affect part of the outflow, either in one hemisphere, or only in some of the outflow layers. From a time-dependent simulation, we illustrate this effect and show that it may not be permanent.Comment: To appear in ApJ

Emission Directives for Tractor Engines

V této bakalářské práci se pojednává o současných emisních normách, které stěžují výrobcům traktorů vývoj nových motorů a o technologiích, které účinně snižují škodlivé látky ve výfukových plynech a jednotlivých výrobcích traktorů a jejich způsobu využití různých technologií.This bachelor´s thesis deals with the current emission standards that complain tractor manufacturers to develop new engines and the technologies that effectively reduce harmful substances in exhaust gases and various tractor manufacturers and their method of use of various technologies.