Volume 65 (2018): Edizione 4 (December 2018)

Recently, the Polish Navy has extended its capability for the implementation of underwater works with autonomous dives conducted beyond the saturation zone to a depth of 80 mH₂O. In the near future it is also planned to introduce long-term dives within typical depths of the saturation plateau.

One of the activities resulting from the analysis of the risk associated with the extension of these competences is the need to conduct a critical review of the system for securing hyperbaric treatment of cases of decompression sickness¹.

The analysis of Berezin and Kiselev’s concept assuming linear association of molecules in a localised adsorption monolayer on the homogeneous surface of a solid adsorbent was carried out. An inconsistency due to the lack of consideration of equilibrium concentration of free adsorption sites in the formulation of the expression for the association constant has been pointed out. It was shown that the correct form of this function leads to the final adsorption equation being identical to the specific case of the Fowler-Guggenheim equation. The obtained result has been generalised to cases of branched adsorbateadsorbate associations. A new adsorption equation limiting the association to at most the dimers has been introduced. Critical conditions for the two-dimensional condensation of the adsorption layer were determined. By applying the formalism of canonical ensemble, full equivalence of the phenomenological and statistical methods was demonstrated in the description of the intermolecular interactions in the localised adsorption monolayer.

This article addresses the practical aspects of the synthesis of an automatic control system for the thrust allocation strategy in the propulsion system of an unmanned underwater vehicle. The vehicle under consideration is a robot submarine equipped with a multi-propulsion system providing four degrees of freedom of movement. The power distribution algorithms are based on limited optimisation methods that allow the determination, on the basis of generalised torques and forces, of how much thrust is required to be produced by individual propulsors. Considering the issue of power distribution as a task of square and linear programming, two algorithms of thrust allocation were proposed and compared. The conducted model tests made it possible to evaluate their quality and efficiency in relation to speed and computational complexity.

Allergic rhinitis occurs in various regions of the world and affects from 10 to 40% of the population. The skin prick test is the “gold standard” for the detection of type I allergic diseases according to the Gella and Coombs classification, which is mediated by IgE. For our experiment, skin prick tests were performed on 60 divers aged between 30 and 40 years of age. The following tests for airborne allergens were used: tests for pollen from trees, grasses, cereals, weeds, proteins from house dust mites, animal hair and epidermis, and moulds. On the basis of an interview and a positive skin prick test allergic rhinitis was diagnosed in 17 divers.

Conclusions:

Allergic rhinitis can cause health problems in divers and be the cause of diving accidents.

Scientific diving is increasingly being used for numerous studies. Moreover, this form of diving allows for the conduction of interdisciplinary research. The current nomenclature of this type of dive is defined as scuba diving to collect information to support science by using diving techniques. Underwater research is particularly important in the natural sciences where it allows for the non-invasive observations of fauna and flora of aquatic ecosystems in their natural environment. At the same time, the use of diving for scientific purposes avoids mistakes made in random sampling, which is related to the use of classical sampling methods. As a result, such diving is crucial in systematic, ecological and behavioural analysis. Nevertheless, dive techniques, however versatile, require optimisation, separate study and systematisation, depending on the type of research conducted. This article is an attempt to present an outline of the topic, to systematise basic concepts in presenting the principles of legal regulations in Poland and abroad..

This paper describes the concept of didactic communication and verifies the course of teaching selected disciplines of water based recreation, i.e. swimming (at the standard technique level), handling a sailing boat whilst undertaking simple manoeuvres, and the basics of diving. At the same time, research in the area of experiments conducted in the field of teaching methods of these disciplines was reviewed in terms of teaching effectiveness, as well as the health and safety of the participants, and ways of communicating while in, on and under the water. Communication between an instructor and a student in any environment which is different from the norm, is difficult owing to its specificity. Additionally, teaching skills on, in or under water requires strict observance of safety rules. Lack of student’s readiness to act in a different water environment, be that based on anxiety or fear, may interfere with or, even prevent didactic communication. Consequently, the effectiveness of teaching decreases. The aim of this work is to search for innovative forms of information transfer that will enable a permanent change in the student’s behaviour, especially when acting in a difficult environment – on the water, in the water and under the water. There are premises to believe that immediate verbal instruction and emphasising the metalinguistic function in it should improve the quality and effectiveness of the process of teaching activities in various water based environments.