Open airscrew VTOL concepts

The following concepts, based on using open airscrew(s) for VTOL maneuvers, are re-examined in light of current technology: (1) tip-driven helicopters, (2) compound helicopters; and (3) high-speed VTOL aircraft, represented by tiltrotors, tiltwings, retractoplanes and stoppable rotors. Criteria, permitting one to compare performance of aircraft using diverse lifting and propelling methods are established. Determination of currently possible performance, indication of near-future potentials, and comparison of those items with the baseline levels (as represented by contemporary shaft-driven helicopters, first generation tiltrotors, and commercial turboprop fixed-wind aircraft) constitutes bulk of this report

Design of Monopole Antennas for UWB Applications

Presented are the design method, equations, and results of a broadband monopole antenna for UWB applications. The antenna is a fat monopole; made of rectangular and circular patches. Measured results show a passband of 2.8–11.97 GHz. Parametric studies of the effects of the ground plane and the gap between the radiating element and the ground plane were done and their results given. The gain and efficiency are also provided; with average values of 4.34 dBi and 96% respectively. The obtained radiation patterns show bi-directional patterns in the E-plane and omni-directional patterns in the H-plane

Issledovanija vlijanija silosirovanija zelenojj massy i sushki sena na zhivuchest' i invazijjnost' metacerkarijj pechenochnojj dvuustki Fasciola hepatica. I. Metacerkarii v silosakh

The results of the studies imply that F. hepatica metacercaria lose their ability to infect the final host (rabbit) as early as in the first days of fermentation process. Chemical and microbiologic analysis of the fermentation process suggest that the loss of infectivity and death of parasites are accounted for by a rapidly changing pH value, determined mainly by the appearance of large amounts of lactic acid in the silages, as well as by a rapid change in the composition of their biochemical flora

Ocena siły fundamentalnej spółek sektora spożywczego na Giełdzie Papierów Wartościowych w Warszawie

The article presents the proposal to apply the (universal) method of assessing the fundamental strength of a company with an example of the Polish food sector. The proposed method belongs to the group of methods of multidimensional comparative analysis and is applicable to the directly immeasurable categories (economic and financial standing, fundamental strength). The problem to be solved is the method of measuring the fundamental strength (attractiveness) of a company. The aim of the paper is to assess the fundamental strength of the food companies in Poland and to identify areas of use the results of research in practical analyses. The article describes how to construct such a measure and how to use it practically. The empirical example included data of food firms listed on the Warsaw Stock Exchange over years 2010–2014. The article presents method for assessing the investment attractiveness of enterprises comprising the food sector in terms of their fundamental strength, namely the long-term investment in their shares.</jats:p