The research reported in this paper is a continuation of the experimentation on the articulation of the Polish /r/ in the intervocalic and postconsonantal positions (cf. Stolarski 2013a and 2013b, respectively). According to Biedrzycki (1978: 83-84), in these two phonetic contexts the rhotic happens to be articulated as a tap. Such an assumption stands in contrast to the widely accepted view that the Polish rhotic is generally realised as a trill. The results reported in Stolarski (2013a) and (2013b) amply prove that in these two environments tapping of the Polish /r/ is extremely frequent. In this article the articulation of the Polish rhotic is examined in the preconsonantal and word-final phonetic contexts. Biedrzycki’s account suggests that in these environments /r/ should be realised as a trill. The results obtained in the current research, however, indicate that even in such contexts the rhotic is mostly tapped. The conclusion which must be drawn from these findings is that the basic allophone of the Polish /r/ is the tap, and not the commonly assumed trill.

Experimental tests were carried out to assess the failure model of steel and basalt fiber reinforced concrete two-span beams. Experimental research was focused on observing the changes in behavior of tested elements in dependence on the ratio of shear reinforcement and type of fiber. The beams had varied stirrup spacing. The steel fiber content was 78.5 kg/m³ (1.0% by vol.) and basalt fiber content was 5.0 kg/m³ (0.19% by vol.). Concrete beams without fibers were also examined. Two-span beams with a cross-section of 120×300 mm and a length of 4150 mm were loaded in a five-point bending test. Shear or flexural capacity of tested members was recorded. The effectiveness of both sorts of fibers as shear reinforcement was assessed and the differences were discussed. It was shown that fibers control the cracking process and the values of deflections and strains. Fibers clearly enhance the shear capacity of reinforced concrete beams.

Poland is expected to enter the Exchange Rate Mechanism II (ERM II). The European Central Bank recommends that the ERM II central rate should reflect the best possible assessment of the equilibrium exchange rate. Since the equilibrium rate is changing in time, it is important to identify the pushing and pulling forces of the exchange rate. This knowledge will let the authorities to defend only the exchange rate that is in equilibrium and to assess outcomes of their actions. We use the VEC approach of Johansen to estimate the behavioral equilibrium exchange rate and to identify the pushing forces of the Polish zloty/euro rate. We apply the Gonzalo-Granger decomposition to calculate the permanent equilibrium exchange rate and to identify the pulling forces of the zloty exchange rate. We demonstrate that this approach may be useful for Polish authorities while entering the ERM II as well as within that mechanism.

A method of planning collision-free trajectory for a mobile manipulator tracking a line section path is presented. The reference trajectory of a mobile platform is not needed, mechanical and control constraints are taken into account. The method is based on a penalty function approach and a redundancy resolution at the acceleration level. Nonholonomic constraints in a Pfaffian form are explicitly incorporated to the control algorithm. The problem is shown to be equivalent to some point-to-point control problem whose solution may be easier determined. The motion of the mobile manipulator is planned in order to maximise the manipulability measure, thus to avoid manipulator singularities. A computer example involving a mobile manipulator consisting of a nonholonomic platform (2,0) class and a 3 DOF RPR type holonomic manipulator operating in a three-dimensional task space is also presented.