Single stage algorithms for pole placement using static output feedback

Paper presents effective formulae, enabling transfer matrix pole assignment. This is accomplished by the use of generalized matrix inverses and the Kronecker product. All the desired pole distributions are covered - namely simple and multiple, real and complex. On this basis one-stage algorithms were developed, avoiding commonly used reduced orthogonality condition. Computational example of the presented algorithms is given

Idea of modernization of medium voltage switching stations examplified by the switchgears RSW and ST7 made by ZWAR

W artykule przedstawiono koncepcję szybkiej modernizacji celki niskiego napięcia w celu dostosowania jej do obowiązujących standardów. Koncepcja polega na pełnej wymianie wyposażenia celki niskonapięciowej i wstawienia w to miejsce nowoczesnego wyposażenia wraz z okablowaniem tak aby zminimalizować możliwość popełnienia błędów i maksymalnie skrócić czas ponownego oddania rozdzielnicy do eksploatacji.An idea of a rapid modernization of a low voltage cell to adapt it to the standards in force has been presented in the paper. The idea consists in a complete replacement of the equipment of the low voltage cell by modern accessories including the cabling to minimize making mistakes and to shorten time most possible to put again the switchgear into operation

Effect of Nanocrystallization Process on the Magnetomechanical Coupling in Fe-Si-B-Cu-Nb Alloy

Magnetic and magnetoelastic properties of the Fe$\text{}_{73.5}$Si$\text{}_{16.5}$B$\text{}_{6}$Cu$\text{}_{1}$Nb$\text{}_{3}$ alloy change considerably during nanocrystallization process. Improvement of magnetic properties is accompanied by the decrease in piezomagnetic parameters such as magnetomechanical coupling and $\Delta E$-effect

DC Magnetic Properties of Amorphous Vitrovac Ribbon

Soft magnetic amorphous Co-based materials prepared by rapid quenching method in the form of thin ribbon are well-known due to their excellent soft magnetic properties as high permeability, low coercivity, and low magnetic losses in kHz range. The amorphous Co-Fe-B-Si material Vitrovac® 6155 U55 produced by Vacuumschmelze GmbH & Co. KG belongs to this class of materials and was investigated in as-delivered state. The aim of this work was to study DC magnetization process by various experimental methods. We have measured magnetization curve by fluxmeter based hysteresis graph and hysteresis loops by three different fluxmeter based hysteresis graphs, exhibiting significant differences. The first and the second hysteresis graph perform the hysteresis loops measurement by the point-by-point method, either with commutative or with summing steps. The third one is AC hysteresis graph working at very low frequencies down to 7 mHz, performing the continuous method. The explanation of this result is based on the structural after effect influencing the domain wall displacement. We assumed that the domain structure consists of very small number of domain walls responsible for magnetization process, which was confirmed by the visualization of static domain structure by a computer-controlled setup based on the Kerr effect

Changes in elm (Ulmus) populations of mid-westernPolandduringthepast35years

Abstract: Three elm species are native to Poland: wych elm (Scots elm) (Ulmus glabra Huds.), field elm (U. minor Mill.), and European white elm (fluttering elm) (U. laevis Pall.). The epidemic of Dutch elm disease (DED) has led to a decrease in the popularity of elm cultivation. An analysis of forestry data was the first step in the assessment of elm resources. The area of forest stands where elms are dominant has more than doubled since 1978. Lowland alluvial forests rank first in regards to the number of elm localities per unit area of a given forest site type. While this site type is clearly preferred by elms, the majority of elm trees are actually scattered among sites of oak-hornbeam or closely related forests (of the alliance Carpinion betuli). Field research revealed a clear dominance of U. laevis, a species which in the past was predominantly located out of woodland and rarely cultivated. Data analysis indicated that all trees greater than 70 cm in diameter belonged to this species. Data from plots surveyed directly also suggest that the three elm species have slightly different habitat preferences. U. laevis prefers riparian habitats, although the major part of its resources is now on potential sites of oak-hornbeam or closely related forests. U. minor even more often than U. laevis occurs at less humid sites (mostly potential sites of oak-hornbeam or closely related forests), while U. glabra prefers moist slopes. In general, it appears that the impact of DED in the last 20-30 years has been smaller than in the preceding period, however, the disappearance of the disease has not been established. Undoubtedly, U. laevis is the elm species that is least impacted by DED

Gradually Devitrified Co-Based Metallic Glass As a Model Material for Testing Néel's Theory of the Rayleigh Rule

It is shown in the present paper that gradually devitrified Co-based non-magnetostrictive metallic glass is an excellent model material to verify Louis Néel's theory of the Rayleigh rule. In the course of the calculations, Néel showed that the parameter p=bH$\text{}_{c}$a (where H$\text{}_{c}$ is the coercivity, a and b are the coefficients of a quadratic polynomial expressing the Rayleigh rule) is expected to range between 0.6 (hard magnets) and 1.6 (soft). However, the experimental values of this parameter, reported in the literature for a number of mono- and poly-crystalline magnets, are much greater than those expected from the theory presented by Néel (in some cases even by two orders of magnitude). The measurements, performed for a series of Co-based metallic glass samples annealed at gradually increasing temperature to produce nanocrystalline structures with differentiated density and size of the crystallites, have shown that the calculated values of the parameter p fall within the range expected from Néel theory

The Influence of Annealing Temperature on Magnetic Properties of Vitrovac 6030

Co-Fe-Mo-Mn-Si-B metallic glass ribbon (Vitrovac 6030) was subjected to the isothermal annealing at temperatures in the range 523-873 K so as to produce a series of samples with gradually coarser microstructure. For this series of samples a giant increase in the coercivity, exceeding three orders of magnitude, is observed. This increase is interpreted in terms of the strengthening of the pinning effect of the nanocrystalline structure on the moving domain walls. It is shown that the anisotropy of the created crystallites is mainly responsible for the increase in the pinning force since the effective anisotropy seen by the wall becomes larger and larger with the gradual increase in the density and size of the grown particles