This paper crowns efforts, made by its author, aiming in showing and proving that the current formula for calculation of the spectra of output signals at A/D converters requires a correcting factor in it. A number of partial results obtained and published in the last years are referred to here. They paved the way to a fully satisfactory and correct result; it is presented in this work. The corrected formula for spectrum calculation is derived using a description of the output signal of an A/D converter by means of the so-called Dirac comb, however not in a direct form, but with taking into account physical reality. In addition, the paper contains a number of interpretative remarks, comments, and explanations - clarifying those matters that have so far been omitted in analyses of the sampling process, despite the fact that they raised various types of doubts.

Our aim is to show that numismatics can provide important information about early history of a settlement in the face of a shortage of other types of evidence. We will study the case of Gdańsk. There is a record on the existence of the town (urbs) of Gdańsk from 997, but no sufficiently considerable archaeological traces of this town were found. Therefore, we do not know where the oldest Gdańsk was located. Most likely, the settlement relics from that time were destroyed as a result of fortification works at the turn of the 18th and 19th centuries. However, the destruction of stratigraphic structures does not mean the destruction of certainly dated historical artefacts, and above all, coins. Registration of early medieval coin finds from the area of Gdańsk provides knowledge of the extent of settlement and functional changes of individual parts of the town complex.

There are 40 coal mines in Poland now. One of them (coal mine “Bogdanka”) is situated in Lublin Coal Basin, other are localised in Silesia and Małopolska regions. Coal mining is a source of large amounts of wastes. Mean annual production of wastes in only Lublin Coal Basin exceeds 2 million Mg, 65% of which is disposed on a heap. The rest is used to restore opencast excavations, to construct and repair local roads and to produce building materials. It seems that large amount of these wastes could be used to construct or modernize flood embankments and dykes. Using mine wastes as building materials requires the knowledge of their geotechnical parameters. A characteristic feature of mine wastes is their gradual weathering which affects geotechnical parameters largely determined by their mineral and petrographic composition.

This paper describes analyses of geotechnical parameters of mine wastes from Lublin Coal Basin (heap near coal mine “Bogdanka”) of various storage times and of samples collected after 10 years of exploitation of a dyke between ponds made of these wastes at the break of 1993 and 1994. Detailed analyses involved: grain size distribution, natural and optimum moisture content, maximum dry den-sity, shear strength and coefficient of permeability. Obtained results were compared with literature data pertaining to mine wastes from Upper Silesian Coal Basin and from other European coal basins.

Performed studies showed that coal mining wastes produced in Lublin Coal Basin significantly differed in the grain size distribution from wastes originating from Upper Silesian Coal Basin and that weathering proceeded in a different way in wastes produced in both sites.

Recent archaeological discoveries have allowed us to examine a series of bracteates from East Pomerania from the late twelfth and the thirteenth century, which has enabled us to construct a new view of medieval coinage in this province. A pivotal role may be attributed to the coins inscribed with the name of Sambor I, the fi rst historical master of Gdańsk, and with the monogrammed name of Otto, which is supposed to refer to St Otto of Bamberg.

The article features an analysis of the ideas of Yurij Levada, an eminent Russian academic, sociologist dealing both with theory and with practice of sociology, a founder of a research institution inMoscow known as Levada-Centre. Levada gave a special place to culture within sociology and he himself called his project on theoretical sociology an “attempt at culturally justified sociology” (grounded in a perspective orientated to culture). The project was based on structurally complex, culturally conditioned and symbolically indirect social actions. In his opinion, such knowledge of culture required to be looked at retrospectively, which provides for tackling the issue of social system reproduction while enabling to understand contemporary culture at the same time. This way of thinking was a basis for Levada’s analyses of the surrounding social reality, e.g. his analyses of intelligence or the concept of “simple Soviet man”.

This paper tries to get a response to the following question: When can a narrowband power amplifier (PA) be considered to be memoryless and when can it not be considered memoryless? To this end, a thorough and consistent analysis of the notions and definitions related with the above topic is carried out. In the considerations presented, two models of the narrowband PA are exploited interchangeably: the black box model widely used in the literature and a model developed here, which is based on the Volterra series. These two models complement each other. In this paper, the conditions for a linear or nonlinear narrowband PA to be memoryless or approximately memoryless or possessing memory are derived and illustrated. They are formulated in terms of the signal delay as well as in terms of the amplitude-to-phase (AM/PM) conversion of the amplifier. Furthermore, the two possible interpretations of the amplitude-to-amplitude (AM/AM) and AM/PM conversions are given a mathematical framework. That is these conversions are presented through some operations. One set of these operations allows to treat the AM/AM and AM/PM conversions as distortions of the modulating signals. Or equivalently as distortions of a given signal constellation when it passes through the PA. Finally, it is proved that the Saleh’s and Ghorbani’s models of the AM/AM and AM/PM conversions occurring in the PAs, which were published in the literature, are not memoryless ones.

The convolution operation used in deterministic network calculus differs from its counterpart known from the classic systems theory. A reason for this lies in the fact that the former is defined in terms of the so-called min-plus algebra. Therefore, it is oft difficult to realize how it really works. In these cases, its graphical interpretation can be very helpful. This paper is devoted to a topic of construction of the min-plus convolution curve. This is done here in a systematic way to avoid arriving at non-transparent figures that are presented in publications. Contrary to this, our procedure is very transparent and removes shortcomings of constructions known in the literature. Some examples illustrate its usefulness.

This paper describes a “distributed method” of introducing the humanitarian engineering principles and concepts to the curriculum of telecommunications at a maritime university. That is by modifying appropriately the syllabi of the telecommunications subjects taught. The propositions made in this area are illustrated by the concrete examples taken from the current Polish Qualifications Framework for the higher education system in Poland. And, for clarity and consistency of presentation, fundamentals and principles as well as a basic terminology and features of this Framework are also highlighted here shortly. Moreover, it has been shown that the approach presented in this paper is more useful compared to a method based on organization of some special courses for students on the humanitarian engineering, in particular when this regards a maritime university.

In this paper, we present some useful results related with the sampling theorem and the reconstruction formula. The first of them regards a relation existing between bandwidths of interpolating functions different from a perfectreconstruction one and the bandwidth of the latter. Furthermore, we prove here that two non-identical interpolating functions can have the same bandwidths if and only if their (same) bandwidth is a multiple of the bandwidth of an original unsampled signal. The next result shows that sets of sampling points of two nonidentical (but not necessarily interpolating) functions possessing different bandwidths are unique for all sampling periods smaller or equal to a given period (calculated in a theorem provided). These results are completed by the following one: in case of two different signals possessing the same bandwidth but different spectra shapes, their sets of sampling points must differ from each other.

The article describes semantic roles of instrumental case (tvoritel’nyj padezh) in Russian and other Slavic languages. Its functions as the instrument, agent, route, temporative, vehicle, comparison, nominal predicate and object of action, and their place in human mental world are considered. Examples of izosemic (standard) and non-izosemic realization of these functions are provided. It is concluded that each semantic role is associated with the specifi c range of lexemes. The idea of interdependence or syncretism of meanings of the instrumental case is discussed. Examples from modern fi ction, where the opposition between certain functions of instrumental case is neutralized, worn off, are provided too. It is hypothesized that in certain discourse circumstances the instrumental case becomes the symbol of common dependency of noun from verb.