On the Arrangement of Pentagonal Columns in Tetragonal Tungsten Bronze-Type Nb18W16O93

The evaluation of HAADF-STEM images of a sample with the composition Nb18W16O93 provided new insights into its real structure. The basic structure comprises an intact octahedral framework of the tetragonal tungsten bronze (TTB) type. The partial occupation of the pentagonal tunnels (PT) by metal–oxygen strings determines the oxygen-to-metal ratio (O/ΣM with M = Nb,W). For a large area, the O/ΣM was determined to be 2.755, which is bigger than the value of Nb18W16O93, which is O/ΣM = 2.735. To a large extent, the three-fold TTB superstructure of Nb8W9O47 with a high oxygen content is present (O/ΣM = 2.765). In addition, a new four-fold TTB superstructure was found in small domains. Nb12W11O63 with an O/ΣM = 2.739 obviously accommodates part of the sample’s metal excess compared to the stable phase Nb8W9O47.

On the Arrangement of Pentagonal Columns in Tetragonal Tungsten Bronze-Type Nb18W16O93

The evaluation of HAADF-STEM images of a sample with the composition Nb18W16O93 provided new insights in its real structure. The basic structure comprises an intact octahedral framework of the tetragonal tungsten bronze (TTB) type. The partial occupation of the pentagonal tunnels (PT) by metal-oxygen strings determines the oxygen to metal ratio (O/SM with M = Nb,W). For a large area, the O/SM was determined to be 2.755 which is smaller than the value of Nb18W16O93 which is O/SM = 2. 735. To a large extent, the threefold TTB superstructure structure of Nb8W9O47 with a high oxygen content is present (O/SM = 2.765). In addition, a new fourfold TTB superstructure was found in small domains: Nb12W11O63 with an O/SM = 2.739 obviously accommodates a part of the sample’s metal excess compared to the stable phase Nb8W9O47.

Influence of the Method of Production of Test Specimens on the Result of the Frost Resistance Test of Concrete

The paper deals with a comparison and interpretation of results of frost resistance tests of concrete specimens taken from a structure and test specimens produced in a laboratory using plastic moulds. A concrete block had to be produced for the experiment to simulate a real structure. The concrete used for the production of this block was also used in a laboratory to produce the test specimens. Core samples were drilled out from the concrete block and were subsequently used to make sets of core specimens. The test specimens, which differed in size, shape and the production method in particular, were subjected to frost resistance tests. The output of the paper is both a comparison of the results obtained on individual types of test specimens and a recommendation on how to approach the determination of frost resistance of concrete in a structure.

OPTIMIZATION OF CALCULATION SCHEMES

Any calculation is preceded by the stage of creating a design diagram of a real structure, which would most accurately correspond to real operating conditions. The more optimally the design scheme is drawn up, the less laborious the stages of calculation and design of the corresponding structure will be. There are practically no results of using this approach when calculating building structures. This article attempts to show the possibility and expediency of using the "Search for solutions" (add-on for Microsoft Excel) at the stage of choosing the optimal parameters of the design design schemeAny calculation is preceded by the stage of creating a design diagram of a real structure, which would most closely correspond to real operating conditions. The more optimally the design scheme is drawn up, the less laborious the stages of calculation and design of the corresponding structure will be. If the efficiency criterion is a linear function, and the variables in the constraint system are also linear, then such a problem is a linear programming problem. Of the listed methods of mathematical programming, the most common and developed is linear programming. To illustrate the idea of the proposed approach, a simple statically definable truss on two supports was deliberately chosen. This is done so that the idea of the proposed approach is not lost due to the complexity and cumbersomeness of the calculations. This article shows the possibility and feasibility of using the "Search for solutions" at the stage of choosing the optimal parameters of the design design scheme. After the design scheme has been defined, more powerful conventional means of calculating building structures can be involved for its complete calculation.

Próba nakreślenia teorii konferencji jako pedagogiczno-artystycznego widowiska kulturowego. Na przykładzie przebiegu konferencji „Od inspiracji do kreacji. Wyzwania edukacyjne i artystyczne”

The aim of the article is an attempt to outline the theory of the conference (scientific), taking into account its actual course, including the reported content, as the ontic basis of its real structure. At the heart of this concept is a myth whose stories form the basis for the emergence of cultural spectacles. In the case of a conference conceived as a spectacle, the founding form (myth) is skholé. The conference itself is shaped in two overlapping areas: firstly, it is subject to the process of ritualization, and secondly, it is subject to the coexistence of universal praxis. In view of the subject of the conference mentioned and analyzed here, this theory takes into account aesthetic and pedagogical interactions (principles), ignoring others (ethics, economy, politics, religion). The conference theory should contribute to the understanding of its coherent thinking and operation structure; the importance of its impact on its participants, the legitimacy of its organization and study; the possibility of consciously shaping its course, in the cognitive - methodological context (I omit the otherwise important socio-cultural aspects).

Enhancing the application potential of dissipative controlled rocking connections through detailing and design

<p>Research on low-damage systems has been significant in the past decade. These systems combine post- tensioning, which provides self-centring; and typically use replaceable devices, which give energy dissipation. WSP has used recent research, carried out at the University of Canterbury, on low-damage bridge piers and applied this into a real structure – the Wigram-Magdala Link Bridge. This is believed to be the first bridge in New Zealand and possibly worldwide to adopt such a system. Given this was the first application of the system to a real structure, there were some valuable learnings during design and construction. Firstly, the application of axial dissipaters has some limitations due to available material sizes, construction difficulty and aesthetics. Secondly, there is still some additional cost and complexity associated with using the low-damage system. Given these difficulties, this paper presents an alternative design philosophy which better captures the benefits of the low-damage system, which include cost-effective repair method, controlled damage and additional robustness and resilience. The alternative design philosophy presented is expected to result in reduced construction costs by reducing pier and foundation demands. Peak displacements and forces will be compared to the results from non-linear time history analysis to verify the performance of the low-damage connection using scaled ground motions. Furthermore, the paper will present the possible application of an alternative dissipation device, the lead extrusion damper, which can further improve the performance of low-damage connections.</p>