Nowadays, noise generated by devices is a serious issue in industry and in everyday life, because it may cause health damage to humans. In this research, a cubic rigid device casing built of double-panel thin steel walls is employed to reduce noise emitted from an enclosed noise source. Double-panel structure is used because of good sound insulation it provides. There exist three main groups of noise reduction methods, i.e. passive, semi-active and active. In this paper, a semi-active modification of double-panel structure is applied and examined. The bistable actuator (solenoid) mounted between incident and radiating plates changes its state due to applied constant voltage, causing the coupling of plates. Experimentally measured natural frequencies and modeshapes of the structure are compared to the simulation results. The influence of proposed modification on dynamical properties of the structure is analyzed and discussed.
The calculations results of the temperature distribution in a 3-phase transformer with modular amorphous core are presented. They were performed for two frequency values which were higher than the power system one. For the 3D field analyses the Finite Element Method (FEM) was used. The calculated temperature at the points of the core surface has been verified using an infrared camera.
The author states that there are in our vocabulary three, and only three, classes of semantic units: a) predicates, i.e. generic concepts – the result of our conceptualization of the world; they represent more than 90% of the vocabulary; b) operators of reference – a small, almost closed set bounding predicates to their concrete denotates; c) proper names, which are by defi nition referentially bound and are object of research of a specialized linguistic discipline. Thus, the main tasks of our grammar are (1) to defi ne and to describe the scope of the grammaticalization in the language in question and (2) to present the semantic classification of predicates, the description of their – bound and/or free – functioning in the text included.
University and the Church need each other. Following the example of Christ incarnated, Christianity “incarnates” the spiritual. The Church and theology need university and cooperation with other sciences to be able to “incarnate” Christ’s issue into our world. Th e university, on the other hand, needs the Church and theology because otherwise it would be deprived of cultural and spiritual foundation: there is no alternative to a discussion about Christ (God and a human). Theology is sometimes defined as scientia fidei; it is determined by the mind and faith. It’s a discussion about God, but due to the Christ event it is also a discussion about mankind. Th erefore it has the form of a dialogue, a discussion. The dialogue is always held in a specific context (nowadays postmodern), in which theology not only has to ask but also answer the question about the meaning. In this sense it is wisdom. Theology as a discussion has to approach the most urgent human problems. These include agnosticism towards which Benedict XVI suggests the “veluti si Deus daretur” rule, relativism in case of which theology cannot stop asking about truth, despair in case of which theology reminds about God, in whom there is no darkness.
The article presents a manner of the collection of sources for the history of towns whose records have been lost. However, Krajenka, a former town of nobility, has archival materials that were introduced to the property records mainly kept in the Kórnik Library and the State Archives in Poznan. The surviving lists of tax dues (hearth tax, poll tax) also facilitate the description of Krajenka’s past.