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Abstract

This paper presents the design and results of mechanism research. A lever mechanism for a gripper was made using monolith technology with constrictions in which the deformations correspond to limited rotation of the links. Unidirectional movement of the drive link is reduced and simultaneously converted into movement of the jaw clamp. Temporary centres of rotation were used to obtain the symmetrical and perpendicular movement of the two ends of the clamp in relation to its axis of symmetry. Computer simulations and tests were performed on a prototype of the gripper mechanism, confirming the adopted predictions of the device’s operation.

Abstract

The aim of the article includes presentation and interdisciplinary analysis of design solutions proposed in the works awarded in the international urban architecture competition entitled “New life between flyovers” and concerning the area around the cross-city railway line, currently under modernization, running through the Śródmieście district in Kraków, from the area of Miodowa Street to the PKP Kraków Główny station. In the applications, possible scenarios of flyovers space development and the possibilities of integrating the transport route into the historic district have been assessed, taking into account historical urban relations and contemporary technical conditions. The analyses were aimed at optimising future investments so that they can become a starting point for public consultations, drafting a land development plan and determination of the development strategy for the studied area. The applied method may be helpful in determining the directions of a spatial policy aimed at the protection of cultural landscape endangered by overground transport routes.

Abstract

The small city is a relatively well examined and widely described subject in literature. Usually, the urban structure of the small city is considered in relation to its original and historical spatial layout with juxtaposition of all subsequent developments in relation to the historical core of given settlement. The article attempts to identify various systems of urban structures in which one of the elements is a group or a single multi-family residential building, examine internal and external scenic relations and determine their impact on the landscape of the small city.

Abstract

The development of particular towns is a factor that determines the economical, social and spatial development of the country. Therefore we turn our attention to it with a critical eye. On 20th October 2015 the government in Poland accepted a bill connected with the Country Town Policy 2023, that is addressed to towns. Its main point is to strengthen towns in their sustainable development, betterment of standards of living and workplace creation. The socio-economical transformation that occurred in Poland in 1989 has caused a lot of changes in the country. In Ukraine it happened in 1991 and it appears that due to various reasons, its transformation seems to be a much longer process and the process has not finished yet. This article focuses on the development of small towns in Ukraine and Poland, which, in currently difficult times, find themselves in a hard and unstable socio-economic situation. This article analyzes the economic, demographic and spatial aspects of small towns in Ukraine and Poland.

Abstract

This paper provides an overview of wind observations in Romania with historical data, particularly after the establishment of the national meteorological network in 1884. Data on wind directions and velocities is presented, focusing on a sample of fourteen cities including the capital Bucharest. The historical evolution of national zonation maps for wind pressure is shown. A statistical description of the maximum annual wind velocity data is also presented.

Abstract

Terrain surface subsidence observed in mining areas results in the flattening of riverbeds and their embankments. This leads to increasingly deep erosion and siltation of riverbeds and surface currents, which causes the emergence of permanent overflow lands. This paper presents hydro – engineering solutions applied in the areas of the mining activity of JSW S.A., which serve the purpose of repairing and eliminating mining damage in the existing infrastructure. The presented repair measures make it possible to eliminate the threat of flooding in mining areas.

Abstract

Sozology is a newly discovered direction in urban planning stem from the growing threats to the natural environment. A contemporary man pursues close and positive relations with the environment and focuses on the premises of human ecology that directly impact the process of planning and composing urban spaces. The article presents the influence of climatic conditions on the shaping of housing areas. The problem was presented on the basis of an analysis of a specific example. The assessment included the shading of the buildings by neighbouring buildings, the shading of the common spaces and the issue of ventilation. These phenomena connected with the structure of the buildings, their scale and intensity have a significant impact on the conditions of the residence. Other factors also affect the housing environment. Their rational use with the help of teams of experts from complementary fields can contribute to raising the standards of the housing environment even at the planning stage, and later to optimising land use by the community of its inhabitants.

Abstract

The paper covers an analysis of guyed masts as per the second order theory. The influence of various types of mast shaft imperfections was analysed based on the example of a certain 200 m-high lattice guyed mast structure with 3 guy levels. The computations were performed taking into account the mast shaft with sway imperfections, imperfections associated with an offset of structure nodes and bow imperfections. As there are no guidelines concerning imperfections in the current European Standard EN 1993-3-1, the permissible assembly deviation values were taken as the reference point. Based on the obtained results of the analysis some final conclusions and comments have been formulated that may be useful in the design of mast structures.

Abstract

A series of thiazole derivatives were synthesized and structurally elucidated by IR, 1H NMR, 13C NMR, mass and elemental analyses. The prepared compounds were screened for their cytotoxic activity against Leukemia HL-60 cell line. Compound 4b was considered as the most promising antitumor candidate among the tested compounds. Mechanism of action of compound 4b evaluated by flow cytometric assay revealed cell cycle arrest at G2/M phase and pre-G1 apoptosis. The ratio of apoptosis was also determined. Moreover, compound 4b increased the concentration of caspase 3 by 4 fold more than untreated control.

Abstract

The main goal of the research was to check the influence of different factors on the mechanical behaviour of the fluidised bed combustion (FBC) fly ash-based geopolymer. Tests have shown that the increasing the proportion of sodium silicate to sodium hydroxide causes a decrease of compressive strength and an increase of flexural strength. The addition of aggregate significantly increased flexural strength but decreases compressive strength. Samples cured at higher temperatures obtained higher strength. Finally, it was concluded that taking into account the mechanical behaviour, FBC fly ash-based geopolymer can be treated as an alternative building material; however, its strength is lower than a metakaolin-based geopolymer made of the same mixture composition.