Modification of the FanWing concept intended for the use at higher speeds of flight (over 20 m/s) is numerically analyzed. The principle of operation, basic aerodynamic characteristics, and the features in untypical flight situation (autorotation) are described and explained.

The objective of this article is to describe the main characteristics of ‘football field’s anti-Semitism’, to understand its main causes, and to answer the question of whether anti-Semitism among football fans constitutes a symptom of one of the kinds of anti-Semitism discussed in the literature of the subject, or is its own kind of phenomenon. Based on reports of racism in Polish and Ukrainian stadiums, press articles, internet material, and in-depth interviews with fans of the Cracovian team Wisła, the authors conclude that football field’s anti-Semitism is a specific type. Even though footballs fans use content characteristic of modern or contemporary religion-based anti-Semitism, the addressees of their hatred are not followers of Judaism, members of the Jewish ethnic group, or the state of Israel, but fans of the opposing teams. Anti-Semitic incidents recur in places with a long history of Polish-Jewish coexistence, where the resulting antagonisms have been retained till today. The figure of the ‘Jew’ appears to be an effective, historically tested, method of showing contempt—the fans make use of the available content to insult their rivals.

“How come you’re not shipping them??? They’re canon”: a look at the language of Italian fandom – The aim of this article is to examine a relatively recent phenomenon in the language of fandom, i.e. various communities of fans that form around a cultural event or artifact, such as a book, a TV show, a movie, etc. This research is located within fan studies, however, it mainly investigates the linguistic aspects of being a fan in Italian. The distinctive feature of the language of fandom as a specific variety, associated with a particular topic and activity and mediated by Internet communication tools, is a specialist lexicon, understandable only to community members. The article concentrates on loanwords from English which in the case of Italian primarily comprise the vocabulary of fandom.

Advanced metallic material processes (titanium) are used or developed for the production of heavily loaded flying components (in fan blade construction). The article presents one process for diagnosing the blade interior by means of laser ultrasonography. The inspection of these parts, which are mainly made of titanium, requires the determination of the percentage of bonded grain sizes from around 10 to 30 μm. This is primarily due to the advantages of a high signal-to-noise ratio and good detection sensitivity. The results of the research into the internal blade structure are attached.

A new ichnogenus and ichnospecies (Solealites ovalis) of etching trace is preserved on the surfaces of clasts from the Savignone Conglomerate (Oligocene) in the Palaeogene Piemonte Basin in NW Italy. It is a shallow, oval depression with a central elevation, which was produced probably by limpet gastropods and served as their home scar, but other gastropods or even sea anemones are not excluded as the trace makers. The conglomerate is interpreted as a deposit of a fan delta, whose clasts have been bioeroded in an intertidal and shallow subtidal shore zone and redeposited to the deeper sea.

In this paper the authors present the test carried out to obtain the uniform velocity distribution at the outlet cross section of flow fan. In the investigations the inner flat vane mounted inside of the impeller has been applied. For various angular position of the inner vane, one obtained different flow structures as well as different velocity distributions. The analysis of the obtained results is presented in form of graphs shown in 10 figures, juxtaposing flow phenomena with velocity distributions. Numerical flow simulation with the use of Flo++ program based on the Finite Volume Method was carried out.

The effectiveness of half flat tip serrations on reducing fan blade trailing edge noise was investigated using experimental methods. The experiments were conducted at an anechoic chamber under different rotating fan speeds. Numerical simulations were performed to investigate the mass flow rate generated by the serrated fan and compared with that by the baseline fan. The experimental results showed that the overall amount of noise reduction decreased with the increasing of the distance away from the fan. It was found that the effectiveness of the serrations was not proportional with the rotating speed of the fan where it was most effective at 263 rpm and 2041 rpm with noise reductions about 3.1 dBA and 3.5 dBA, respectively. This phenomenon might be depended on how trailing edge vortex would interact with the serrations at different speeds of the fan. The reduction of mass flow rate reduced with the increasing of the rotating speed and the highest reduction was found at 263 rpm which was about 18% and this reduction was accompanied by overall noise reduction of 3.1 dBA.

In recent decades, two different approaches to mine ventilation control have been developed: ventilation on demand (VOD) and automatic ventilation control (AVC) systems. The latter was primarily developed in Russia and the CIS countries. This paper presents a comparative analysis of these two approaches; it was concluded that the approaches have much in common. The only significant difference between them is the optimal control algorithm used in automatic ventilation control systems. The paper describes in greater detail the algorithm for optimal control of ventilation devices that was developed at the scientific school of the Perm Mining Institute with the direct participation of the authors. One feature of the algorithm is that the search for optimal airflow distribution in the mine is performed by the system in a fully automated mode. The algorithm does not require information about the actual topology of the mine and target airflows for the fans. It can be easily programmed into microcontrollers of main fans and ventilation doors. Based on this algorithm, an automated ventilation control system was developed, which minimizes energy consumption through three strategies: automated search for optimal air distribution, dynamic air distribution control depending on the type of shift, and controlled air recirculation systems. Two examples of the implementation of an automated ventilation control system in potash mines in Belarus are presented. A significant reduction in the energy consumption for main fans’ operation obtained for both potash mines.