In total, there are 12 systems, 60 point groups and 89 single forms in crystals and quasicrystals. Among them, 5 new systems, 28 new point groups and 42 new single forms belong to quasicrystals, while the other 7 syst...In total, there are 12 systems, 60 point groups and 89 single forms in crystals and quasicrystals. Among them, 5 new systems, 28 new point groups and 42 new single forms belong to quasicrystals, while the other 7 systems, 32 point groups and 47 single forms belong to crystals. In this paper, the point groups and single forms of quasicrystals are deduced and drawn as stereographic projections by the rules of crystallographic point groups. These stereographic projections integrate the crystal and quasicrystal symmetry theories.展开更多
Some mathematical aspects of the Lie groups SU (2) and in realization by two pairs of boson annihilation and creation operators and in the parametrization by the vector parameter instead of the Euler angles and ...Some mathematical aspects of the Lie groups SU (2) and in realization by two pairs of boson annihilation and creation operators and in the parametrization by the vector parameter instead of the Euler angles and the vector parameter c of Fyodorov are developed. The one-dimensional root scheme of SU (2) is embedded in two-dimensional root schemes of some higher Lie groups, in particular, in inhomogeneous Lie groups and is represented in text and figures. The two-dimensional fundamental representation of SU (2) is calculated and from it the composition law for the product of two transformations and the most important decompositions of general transformations in special ones are derived. Then the transition from representation of SU (2) to of is made where in addition to the parametrization by vector the convenient parametrization by vector c is considered and the connections are established. The measures for invariant integration are derived for and for SU (2) . The relations between 3D-rotations of a unit sphere to fractional linear transformations of a plane by stereographic projection are discussed. All derivations and representations are tried to make in coordinate-invariant way.展开更多
The design and measuring potential of the latest generation of the magnetic scanner called Magscanner-Maglab System （MMS） was presented. It enabled the fast acquisition of 3D signals from magnetic sensors and their ...The design and measuring potential of the latest generation of the magnetic scanner called Magscanner-Maglab System （MMS） was presented. It enabled the fast acquisition of 3D signals from magnetic sensors and their visualization as digitalized mag- netic images. This system was used for monitoring of a thermal demagnetization process of permanent magnets. The original method and measurement devices were capable for examination of magnetic, mechanical and thermal defects in cylindrical rods made of NdFeB and non-rare earth components. Effectiveness of the method and device was tested for the reference demagnetized magnet dedicated for magnetostrictive actuators.展开更多
文摘In total, there are 12 systems, 60 point groups and 89 single forms in crystals and quasicrystals. Among them, 5 new systems, 28 new point groups and 42 new single forms belong to quasicrystals, while the other 7 systems, 32 point groups and 47 single forms belong to crystals. In this paper, the point groups and single forms of quasicrystals are deduced and drawn as stereographic projections by the rules of crystallographic point groups. These stereographic projections integrate the crystal and quasicrystal symmetry theories.
文摘Some mathematical aspects of the Lie groups SU (2) and in realization by two pairs of boson annihilation and creation operators and in the parametrization by the vector parameter instead of the Euler angles and the vector parameter c of Fyodorov are developed. The one-dimensional root scheme of SU (2) is embedded in two-dimensional root schemes of some higher Lie groups, in particular, in inhomogeneous Lie groups and is represented in text and figures. The two-dimensional fundamental representation of SU (2) is calculated and from it the composition law for the product of two transformations and the most important decompositions of general transformations in special ones are derived. Then the transition from representation of SU (2) to of is made where in addition to the parametrization by vector the convenient parametrization by vector c is considered and the connections are established. The measures for invariant integration are derived for and for SU (2) . The relations between 3D-rotations of a unit sphere to fractional linear transformations of a plane by stereographic projection are discussed. All derivations and representations are tried to make in coordinate-invariant way.
文摘The design and measuring potential of the latest generation of the magnetic scanner called Magscanner-Maglab System （MMS） was presented. It enabled the fast acquisition of 3D signals from magnetic sensors and their visualization as digitalized mag- netic images. This system was used for monitoring of a thermal demagnetization process of permanent magnets. The original method and measurement devices were capable for examination of magnetic, mechanical and thermal defects in cylindrical rods made of NdFeB and non-rare earth components. Effectiveness of the method and device was tested for the reference demagnetized magnet dedicated for magnetostrictive actuators.
