Chaotic vibrations in a regenerative cutting process

We have analyzed vibrations generated in an orthogonal cutting process. Using a simple one degree of freedom model of the regenerative cutting we have observed the complex behaviour of the system. In presence of a shaped cutting surface, the nonlinear interaction between the tool and a worpiece leads to chatter vibrations of periodic, quasi-periodic or chaotic type depending on system parameters. To describe the profile of the surface machined by the first pass we used a harmonic function. We analysed the impact phenomenon between the tool and a workpiece after their contact loss.Comment: 7 pages, 3 figure

Majorana neutrino versus Dirac neutrino in e+e−→W+W−{\rm e}^{+}{\rm e}^{-} \to {\rm W}^{+}{\rm W}^{-} through radiative corrections

Radiative corrections to ${\rm e}^{+}{\rm e}^{-}\! \rightarrow {\rm W}^{+}{\rm W}^{-}$ from Majorana neutrinos are studied in the context of the see-saw mechanism. Focusing on the effects of the fourth generation neutrinos, we calculate W-pair form factors, the differential cross sections and the forward-backward asymmetries for the polarized electrons at one-loop level. The behaviour of the form factors at the threshold of Majorana particle pair productions is found to differ from that of Dirac particle pair productions. In the cross section for unpolarized electrons, the radiative corrections, depending on the mass parameters of the see-saw mechanism, are found to be $\sim 0.5\%$ at the energy range of the LEP200 and the next generation linear colliders.Comment: 10 pages, Latex, 4 figures(no included, available on request

Subsurface water storage and runoff processes in layered hillslope

Thesis--University of Tsukuba, D.Sc.(A), no. 449, 1987. 3. 2

Surface Quality of a Work Material Influence on Vibrations in a Cutting Process

The problem of stability in the machining processes is an important task. It is strictly connected with the final quality of a product. In this paper we consider vibrations of a tool-workpiece system in a straight turning process induced by random disturbances and their effect on a product surface. Basing on experimentally obtained system parameters we have done the simulations using one degree of freedom model. The noise has been introduced to the model by the Langevin equation. We have also analyzed the product surface shape and its dependence on the level of noise.Comment: 12 pages, PDF of figures can be obtained from http://archimedes.pol.lublin.pl/~raf/graf/fpic.pd

Interferometric Observations of the T Tauri Stars in the MBM 12 Cloud

We have carried out a millimeter interferometric continuum survey toward 7 YSOs in the MBM 12 cloud. Thermal emissions associated with 2 YSOs were detected above the 3-$\sigma$ level at 2.1 mm, and one also showed a 1.3 mm thermal emission. Another object was marginally detected at 2.1 mm. Spectral energy distributions of the YSOs are well fitted by a simple power-law disk model. Masses of the circumstellar disks are estimated to be an order of 0.05 M_{\sun}. The circumstellar disks in the MBM 12 cloud have properties in common with the disks in nearby star-forming regions, in terms of disk parameters such as a disk mass, as well as an infrared excess.Comment: 9 pages, 3 figures, accepted by ApJ Letter