In technology of coal fines beneficiation in Poland mainly fines jigging processes are in use. In case of steam coal fines beneficiation it is till 80% of the whole amount of produced assortments, while in case of coking coal fines it is 100%. The necessary condition of not homogenous feed separation which is directed to beneficiation process in pulsating water stream is a sufficient liberation of particles. The stratification of particles in working bed causes that particles of certain size, density and shape gather in individual layers in working bed of jig. The introduction of sufficient amount of additional water determines appropriate liberation of particles group, which generates partition into concentrate and tailings. The paper presents the results of sampling of industrial jig used for the beneficiation of coal fines by three various settings of additional amount of water under sieve which is directed to jigging. These amounts were equal to 35, 50 and 70 [m3/h]. Collected samples of separation products were then sieved into narrow particle size fractions and divided into density fractions. In such narrow size-density fractions the coordinates of partition curves were calculated for tailings of hard coal fines, which were subsequently approximated by means of Weibull distribution function. The separation precision measured by separation density, probable error and imperfection were determined on the basis of obtained model separation curves. The evaluation of separation effects was performed for a wide particle size fraction: feed directed to jigging process and narrow particle size fractions. The analysis of separation results in size-density fractions allowed to determine the influence of particle size change on the value of probable error. The results of separation precision in size-density fractions were compared with effects of separation of wide particle fraction, i.e. feed directed to jigging process.
The article portrays the motif of dream and its symbolic meanings in Vladimir Nabokov’s short story Terror, what has not been the subject of detailed research so far. It has been determined that the experience of dream in the analysed story denotes the protagonist’s attempt to escape from the surrounding world and a shift into the sphere of the unconscious (mysterious anaesthesia). Thus the topos of dream/dream fantasy in Terror implies the existence of a hero in a particular kind of chronotope, and is connected with the semantics of the passage – from demonic chaos and metaphysical terror to restoration of cosmic (microcosmic) order and to “becoming oneself” (Ricoeur). Moreover, dream in Nabokov’s text is intrinsically linked with the problem of compatibility/ incompatibility of the two worlds: the real and the oneiric one, existing in reality and reflected in a mirror, and also with the motif of a doppelganger which bears references to Dostoyevsky’s writings. Also, an oneiric image of a laughing woman is analysed in detail in the article. It has been proven that laugter (giggle) of the story’s heroine unveils ambivalent and demonic dimension of femininity and is a reference to Pushkin’s The Queen of Spades.
The contemporary warfare seems to have great influence on the way social sciences position themselves within the socio-political contexts of today. This is being implemented in many cases by the geopolitical context of 9/11 and the fall of former centers of power (end of the Cold War). Cultural anthropology, which shared a similar dilemma in the formative period of its own history provides us today with one of the most controversial examples in this matter. The program initiated by US Army back in 2006 called Human Terrain System started a wide spread debate on ethical issues regarding doing ethnographic fieldwork in a militarized landscape. HTS became thus a field of intellectual and political polemics between certain groups of researches. The academic and political debate on HTS seems to be put in a post-colonial context as a new form of mixing of science and ideology. This paper tackles the problem of emergence of a new type of anthropological understanding of the cultural other and as well its own methods and ethical standards in a situation, where crisis seems to be a permanent state of the discipline and the world its trying to describe.