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Former and contemporary threats to historic gardens
Get PDFIn this paper, the comparison of former and contemporary threats to the value of historic gardens has been carried out. The analysis was based upon the publication of Majdecki, dating back to the 80s and 90s of the 20th c., being treated as a reference to the currently observed negative practices. In this article, verification of the earlier classification of phenomena, constituting a threat to the historic gardens, was suggested. Observations by the authors and scientific publications from the recent ten years have been adopted as the basis for conclusions and syntheses
New forms of settlement – a need or a fancy?
Get PDFAt present, there are contrasting tendencies in land development in rural areas. A pressure for investment as well as re-migration of people beyond the city can be observed in the city outskirts. In these areas, the agricultural function is disappearing and residential development is becoming dominant. Both spontaneous and planned development exhibit multiple negative features. There is a need for a new model or housing development in these areas that is different from urban and rural forms and constitutes their synthesis. It is necessary to break great monocultural areas of the suburbs into individualized, both in the functional and spatial aspects, units enabling extraterritorial leisure. The colour-material integration of particularly roofs and exposition of figure dominants may reduce the chaos and enrich the landscape
A Comparison of Hydrodynamic Models of Different Hybrid, Fluidised-Bed Bioreactors
Get PDFThis is a preliminary study of hybrid fluidised-bed bioreactors considered the hydrodynamic models and their comparison. In this type of bioreactor, there are two characteristic components which determine their work mode. One part of the bioreactor works as a twophase, gas-liquid, air-lift bioreactor. The second part is a two-phase, liquid-solid, fluidisedbed bioreactor. This type of construction provides high biomass concentration and low shear forces which influence biofilm. Two different types of construction of hybrid fluidised-bed bioreactors were proposed: with external or internal draft tube. Two different mathematical models are needed to design and analyse the operation of these devices
Accounting for time-dependent effects in the construction stage FEM analysis of composite pre-stressed bridge girders
Get PDFIn this paper, the results of the numerical analysis of pre-stressed concrete girders made of a high-strength concrete composite with a slab made of normal concrete are presented. A FEM analysis of the construction stage considering the influence of rheological effects on the behaviour of the structure was performed. Results of the analysis are presented in the work and are compared with the results of numerical analysis of the same elements, in which the time-dependent effects are not included. On the basis of these results, appropriate conclusions are proposed
FMEA analysis of a hydraulic cylinder using artifical neural network.....67 G. Filo: Asynchronous buffer read method in development of DAQ application for supporting research of hydraulic systems
No full textThis paper presents Failure Mode and Effects Analysis (FMEA) on the hydraulic cylinder using matrix analysis and artificial neural network. Functions for each cylinder components were identified. Also relationships between pairs for interacting components and their potential failures where identified. Training and testing of an artificial neural network was conducted in MATLAB software environment
Overview of aircraft technology solutions compatible with the concept of mea
Get PDFThe purpose of this paper is to present some selected issues relating to the alternative application of the perspective concept on the plane board MEA (More Electric Aircraft), instead of the traditional solution, in terms of power (pneumatic and hydraulic systems). In the context of the analysis of this trend, particular attention is paid to the major advantages that aeroplanes have, made in accordance with the new technology and problems in autonomous systems of electricity generation (electric power grid of aircraft). Considering that the largest growth of the above trend of electric aircraft (MEA) applies to civil aviation, the most important role in this paper was assigned to civilian aircraft (Boeing, Airbus) in the context of power distribution in electro-energy systems. In addition, a review of air sources of electricity (electric power) generation was made for particular types of energy sources (generators, generator-starters, transformers, converters, etc.) and advanced on-board autonomous power systems ASE (Autonomous Electric Power Systems), used in most modern aircraft constructions (passenger and military aircraft). In the final part of this paper, based on a literature review of electric aircraft concepts (MEA) and a brief analysis, the main conclusions arising from the application of this trend in modern aviation are presented
Dilemmas of authenticity – between permanent ruin and rebuilding
Get PDFThe architectural object is a witness of its age. Its form is the result of once existing requirements and fulfilling defined needs. Over time, however, conditioning is changing, repeated destructions and transformations causing that a historic building stops responding to original assumptions. In consequence a need of assigning a new role to monuments appears: a purely museum-like relic or a fully functioning architectural space adapted to modern expectations. It seems that in spite of functioning regulations, undertakings effected in the last decades depict a different level of taking a stance on the authenticity residing in a historic structure. Perhaps there is a need to take another look at the model of conservator’s action adequate for redefining the position in view of the protection of historic values, withthe possibility of considering additional decisions, towards specific objects and circumstances
Simulation of concrete corrosion and interaction surfaces using cellular automata
Get PDFThis paper presents a new approach to determining the synergetic effects of environmental conditions and mechanical loading on the load bearing capacity of structural members. Cellular automata are used to estimate the residual strength of a RC section subjected to concrete corrosion. The evolution of interaction surfaces resulting from bending moments and axial force caused by a continuous degradation process is presented
Historical overview of the importance of building materials in architecture
Get PDFThe title of the conference Defining architectural space – Games and play of architecture should be regarded as a kind of intellectual provocation, given that without a profound comment, these “games and play” should above all be understood as extremely costly ones. However, taking for granted the “game” motif (in the sense of artistic manipulation of the structure’s shape and detail embedded in space), the author has decided to raise the subject of the role that building and finishing materials play in the design concept and practice of the architect
Non-invasive diagnostics of the rotor the asynchronous motor with using start up stator current
Get PDFThis article presents the idea of asynchronous motor’s non-stationary stator starting current, filtration methods, in the non-invasive diagnosis of the rotor cage. The mathematical description of the selected analysis forms is omitted in favor of an indication of the practical aspects of the method application and the obtaining of sample analysis results. The object of the study was the single cage induction motor with exchangeable rotors for different faults, machine’s load was a generator with field current control system, which was used to control the load torque