The article regards aspects of PV modules tested with the use of natural sunlight. The analysis of spectral structure of solar energy resources in southern Poland, carried out on the basis of meteorological data originating from SolarLab PW Wrocław and AGH Kraków, Poland [1] was used in the article. It is a continuation of the article: Analysis of solar energy resources in southern Poland for photovoltaic applications [1], describing the method to determine spectral parameters of average photon energy (APE) and useful fraction (UF) with the use of a solar radiation spectrum simulator. This article, however, includes an experimental presentation of their impact on PV conversion of modules with different absorbers. Theory and practice of the measurements were described with the use of spectral parameters such as: UF, APE. Their influence on the efficiency of modules’ photovoltaic conversion with various spectral characteristics of absorbers was presented. The most recent methods described, which characterise the structure of solar energy resources such as annual distributions of APE and UF, have not been commonly used yet in Poland and other countries, even though they most precisely define adjustment of the spectral factor to the selected PV module.

Practical application of UF, in detection of absorber type used in the tested PV module/cell is demonstrated in the final part of the article.

We propose contents of topographic maps for polar areas to be supplemented with such landforms that are easily identified during the analysis of air or terrestial photographs. Such landforms include rock outliers (monadnocks), glacial boundaries, a beach and thick mantles of tundra vegetation. All these landforms create together with fluvial and lake patterns a system of elements that enable location of users and therefore make preparation of other (e.g. geological, geomorphological or glaciological) maps possible.

This article provides an initial analysis, from a historical standpoint, of the problematic nature of conceptualizations of the notion of gene in molecular genetics. The starting point is an historical outline of the relation between classical genetics and molecular genetics; it is indicated how the conceptual baggage of classical genetics influenced the development of the concepts of gene used later in molecular biology. I also reveal two problems of genes in the philosophy of science, i.e., skepticism concerning genes and the concept of nominal gene. I conclude that concept of gene functioning within the framework of molecular genetics should be considered from the point of view of experimentalism and pragmatism. It seems that the concept of gene on the molecular level should be conceptualized—in order to remain functional—as broadly as possible and in relation to genetic material.

Contemporary sensorless AC drives require the use of electromechanical quantities estimation. The skin effect occurring in AC machines with solid secondary or with solid secondary elements causes machines of this type to be represented by equivalent circuits containing distributed elements, which makes the analysis of machine electrodynamic states more complicated and hinders the construction of relatively simple and effective estimators of electromechanical quantities. The variability of rotor parameters is modelled, with a good approximation, by the machine secondary multi-loop equivalent circuit with lumped elements. In this paper the construction procedure of electromechanical state variable estimators basing on this type of equivalent circuit will be presented. The simulation investigations of the created electromechanical quantities estimators, performed for the selected states of solid iron rotor AC machine operation will be shown as well.

This paper investigates the behaviour of axially-loaded tubular columns filled with M20 grade concrete and partially replaced concrete. The parameters varying in the study are slenderness ratio (13.27, 16.58 & 19.9), and normal M20 grade concrete, partially replaced quarry dust and concrete debris. The effects of the various concrete mixes and composite action between the steel tube and the concrete core are studied and a graph visualizing the differences between the load carrying capacity and the axial deflection is plotted. Some of the performance indices like the Ductility Index (DI), Concrete Contribution Ratio (CCR), Confinement Index (θ) and Strength Index (SI) are also evaluated and compared amongst the CFST columns. From the results it has been noted that an increase in the L/D ratio decrease the behaviour of the composite columns irrespective of the in filled materials. The composite action was achieved in the CFST columns filled with partially replaced quarry dust and concrete debris when compared with hollow steel columns. The load carrying capacity of the CFST column increases by 32 % compared with the hollow tubular columns.