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Number of results: 112
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Abstract

Designer drugs cause irreversible changes in the brain and put those who take them at an increased risk of developing Alzheimer’s and Parkinson’s disease. They can also affect one’s genetic material, says Prof. Krystyna Gołembiowska from the PAS Institute of Pharmacology.
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Abstract

The aim of this study is to find the cost design of RC tension with varying conditions using the Artificial Neural Network. Design constraints were used to cover all reliable design parameters, such as limiting cross sectional dimensions and; their reinforcement ratio and even the beahviour of optimally designed sections. The design of the RC tension members were made using Indian and European standard specifications which were discussed. The designed tension members according to both codes satisfy the strength and serviceability criteria. While no literature is available on the optimal design of RC tension members, the cross-sectional dimensions of the tension membersfor different grades of concrete and steel, and area of formwork are considered as the variables in the present optimum design model. A design example is explained and the results are presented. It is concluded that the proposed optimum design model yields rational, reliable, and practical designs.
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Abstract

This paper is dedicated to Voivodship Park of Culture and Recreation in Chorzów (Silesia Park) – one of the biggest of its kind in Poland and in Europe (ca. 600 ha of total area). Construction of the Park had begun in 1954 according to the design under the direction of prof. Władysław Niemirski. After many years it became an example of successful land remediation and re-naturalization of anthropogenic landscape. The whole facility though formally created in socrealism style, actually represents classical modernism’s features inspired probably by American parks with a rich recreation program.
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Abstract

Green spaces are an integral element of urban structures. They are not only a place of rest for their users, but also positively affect their well-being and health. The eff ect of these spaces, is the better, the smoother they create larger urban layout – stings of greenery. The introduction of urban greenery can and should be one of the basic elements of revitalization. Often, however, greenery is designed without multi-aspect analysis, enabling understanding of conditions and the use of existing potential in a given place. The use of computational design in conjunction with the use of generally available databases, such as numerical SRTM terrain models, publicly available OSM map database and EPW meteorological data, allows for the design of space in a more comprehensive way. These design methods allow better matching of the greenery design in a given area to specific architectural, urban and environmental conditions.
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Abstract

Like other harbour cities in Europe, Lisbon has an axial development anchored in pre-existing confi gurations which dot from east, more industrial areas, to the west, a more monumental and urban type. The diversity of fabrics and the overlapping of various time layers become decoded through a functional specialization infrastructural line, which, from rural, becomes increasingly infrastructured as part of the on-going reinvention of the city of Lisbon.
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Abstract

This paper addresses the tensile and flexural strength of HPC (high performance concrete). The aim of the paper is to analyse the efficiency of models proposed in different codes. In particular, three design procedures from: the ACI 318 [1], Eurocode 2 [2] and the Model Code 2010 [3] are considered. The associations between design tensile strength of concrete obtained from these three codes and compressive strength are compared with experimental results of tensile strength and flexural strength by statistical tools. Experimental results of tensile strength were obtained in the splitting test. Based on this comparison, conclusions are drawn according to the fit between the design methods and the test data. The comparison shows that tensile strength and flexural strength of HPC depend on more influential factors and not only compressive strength.
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Abstract

The article presents the ideas of flexible design in the construction sector. Flexibility in the construction sector was discussed and defined between typical and flexible approaches to design. The idea applied during the economic effectiveness analysis of construction projects was introduced. The issue of flexibility was discussed based on the example of construction of a sports facility - The National Stadium in Warsaw. An effectiveness analysis was applied for variant solutions.
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Abstract

U-turn lanes eliminate left turns at intersections and allow the manoeuvre to be made via median crossovers beyond the intersection. However, there are many situations where road infrastructures are characterized by the reduced width of the median. It is clear that, in such situations, we must adopt design criteria that take into account limitations imposed by the width of the cross-section of the road. This is the reason why it is necessary to adopt design solutions which expect a complete reorganization of the road section affected by the insertion of U-turns. In this paper, we intend to propose original guidelines for U-turn lane design, suitable to guarantee both the necessity to offer a high level of functionality of the road sections to be implemented by U-turns, and the principles of safety in order to reduce unsafe conditions during inversion manoeuvres as much as possible.
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Abstract

The cyclic modular approach is proposed for mechatronic object design. The approach is based on a new conceptual model of the object and a new algorithm of its design. The model consists of invariant and changeable parts. The parts have a hierarchical structure. The proposed algorithm allows for creating the object from the basis principle to the construction step by step. It makes it possible to design an adequate object in all forms of its representations: structure, schematic diagram, mathematical model and construction. Each of these forms has an invariant part, i.e. the structure of the functioning process of the object. Application of the proposed approach reduces the time needed for the object design.
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Abstract

The contemporary underground mining of raw minerals is more and more associated with geological and mining software packages which support the work of designers from the moment of the exploration of a deposit, determination of its size and quality, geological, hydrogeological and tectonic conditions, by planning the development and cutting of the deposit. Production planning is one of the most important activities carried out in the course of a mining project, because it allows to set specific production results of a mine in relation to a time unit, and then allows for a verification of the degree of completion of the assumed plan. At present, computer-aided design is applicable to daily or long-term output planning taking deposit, qualitative, quantitative and cost constraints into account. In the article, selected forms of ore deposits were presented. On the basis of several dozen boreholes up to 300m in length, an exemplary fragment of the ore cutting model using computer-aided design of mining works was presented. By using modern computer software - ABB MineScape with modular construction, the possibilities of improving the process of development of future exploitation areas have been determined. In particular, the arrangement of boreholes, based on which ones the cross sections were made with, present the exemplary lithostratigraphic thickness of layers, including the location of discontinuous deformations in the form of faults, and an ore bearing zone. For the block model, resources with priority for metal N o. 1 and 2 were calculated. I n the last section of the article, the cutting idea for a shallow ore deposit has been presented. The degree of effective use of the deposit has been analysed for the room and pillar mining method.
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Abstract

A new 4-D dynamical system exhibiting chaos is introduced in this work. The proposed nonlinear plant with chaos has an unstable rest point and a line of rest points. Thus, the new nonlinear plant exhibits hidden attractors. A detailed dynamic analysis of the new nonlinear plant using bifurcation diagrams is described. Synchronization result of the new nonlinear plant with itself is achieved using Integral Sliding Mode Control (ISMC). Finally, a circuit model using MultiSim of the new 4-D nonlinear plant with chaos is carried out for practical use.
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Abstract

In the Act on Revitalization of 9 October 2015, for the first time in Poland, the legal act introduced the necessity to apply the principles of universal design (Article 3 paragraph 2 point 3). The practice of investment processes in crisis areas shows that the requirements set out in the Act are not properly implemented. Regeneration processes require attention to improve the quality of life of residents. The article presents issues related to the implementation of universal design principles during revitalization processes. There is a noticeable lack of interest in this issue despite the fact that it is one of the three tasks set before local governments in the Revitalization Act, after social participation and support for people at risk of exclusion in the area of housing. The reasons for this state should be seen in a small knowledge of the issue, deficiencies in the educational process of designers and poor control on the part of local governments and central authorities. This is due to conservation conditions, which often misinterpret the right to protect cultural heritage. The self-government as its own task should guarantee the possibility of using the positive effects of the revitalization process, in particular the implementation of residents’ rights to an independent and dignifi ed life, which is required by the UN Convention on the Rights of Persons with Disabilities.
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Abstract

The reminiscences about prof. Tadeusz Bartkowicz focus on the figure of the significant founder of the Kraków school of urban design and spatial planning as well as environment protection. The synthetic presentation of his considerable accomplishments in this field has been based on the review of his scientific and urban planning work, personal contacts with Professor and the works of other scholars, friends and students.
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Abstract

The paper analyses the influence of seasonal temperature variations on fatigue strength of flexible and semi-rigid pavement structures chosen for KR4 traffic flow category. The durability of pavement determined assuming a yearly equivalent temperature of 10˚C and assuming season-dependent equivalent temperatures was compared. Durability of pavement was determined with the use of Asphalt Institute Method and French Method. Finite Element Method was applied in order to obtain the strain and stress states by the means of ANSYS Mechanical software. Obtained results indicate a considerable drop in pavement durability if seasonal temperature variations are considered (up to 64% for flexible pavements and up to 80% for semi-rigid pavements). Durability obtained by the French Method presents lower dependence on the analysed aspect.
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Abstract

This study aims to design a novel air cleaning facility which conforms to the current situation in China, and moreover can satisfy our demand on air purification under the condition of poor air quality, as well as discuss the development means of a prototype product. Air conditions in the operating room of a hospital were measured as the research subject of this study. First, a suitable turbulence model and boundary conditions were selected and computational fluid dynamics (CFD) software was used to simulate indoor air distribution. The analysis and comparison of the simulation results suggested that increasing the area of air supply outlets and the number of return air inlets would not only increase the area of unidirectional flow region in main flow region, but also avoid an indoor vortex and turbulivity of the operating area. Based on the summary of heat and humidity management methods, the system operation mode and relevant parameter technologies as well as the characteristics of the thermal-humidity load of the operating room were analyzed and compiled. According to the load value and parameters of indoor design obtained after our calculations, the airflow distribution of purifying the air-conditioning system in a clean operating room was designed and checked. The research results suggested that the application of a secondary return air system in the summer could reduce energy consumption and be consistent with the concept of primary humidity control. This study analyzed the feasibility and energy conservation properties of cleaning air-conditioning technology in operating rooms, proposed some solutions to the problem, and performed a feasible simulation, which provides a reference for practical engineering.
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Abstract

The subject of this paper is the study of the specificity of the transformation of the urban public spaces of the Western world and the problem of the multi form nature of this phenomenon. The Author uses such concepts as that of the "hybrid" and of "hybridization" borrowed from the field of natural sciences and explains the reasons for their introduction within this specific scope of research in a broad manner.
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Abstract

This article presents a case study of a large wedge failure. It took place during excavation of the last bench of storage cavern with an approximate dimension of 80 m long having a depth of 8 m. The adopted intervention followed a structured approach, which included immediate rock support, geotechnical and geological investigations in the failure zone and design modifications. Back analyses of the failure zone were also carried out to assess design parameters with observed geological conditions. Re assessment in the failure zone was carried out using modified design parameters, which included shorter benches, rock support installation schemes such as longer rock bolts, reinforced ribs of shotcrete and reduced construction advances. Geotechnical monitoring in and around failure zone were carried out for recording any alarming movements in the rock mass. Initially, geotechnical monitoring was carried out in the recently excavated zone of the cavern on a daily basis. Based on continuous monitoring data for at least one week, the frequency of subsequent monitoring can be decided. In most cases the deformation of rock mass was considerably less than the alarming values which were calculated based on detailed design for different rock classes. The paper discusses the failure, investigation, cause, assessment and remedial measures to complete the construction of cavern.
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Abstract

The paper investigates the supply structure of the capacity market in Poland in the coming years. The results of the capacity auctions conducted in 2018 are analyzed for this purpose. Three auctions were held at that time. The products traded in the capacity market are capacity obligations for the following years: 2021, 2022 and 2023. The auctions were organized in accordance with (i) he Act of December 8, 2017 on the Capacity Market and the (ii) Capacity Market Regulations published by the Polish Power Grid. The source of data used in this study is the official information of the President of the Energy Regulatory Office on the final results of the main auctions for 2021–2023 delivery periods. The list of the capacity suppliers who won capacity auctions contains the type of capacity market units, the volume of capacity obligations, the duration of capacity agreements and the business name of the capacity suppliers. The conducted analysis indicates that the auction for 2021 was won mainly by existing units (45.81%) and refurbishing units (33.51%). In subsequent years, the share of existing generating units is significantly higher and amounts to 91.67% for 2022 and 84.54% for 2023. The results of the study carried out in this paper also show that one energy company, being the owner of power generating daughter companies, has a very high share in these capacity auctions. The PGE Capital Group contracted 51.95% for 2021, 69.92% for 2022 and 64.44% for 2023 of the total capacity obligation. The volume amounts to over 70% of their total installed capacity.
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Abstract

The economic envelopes obtained by optimization techniques in open pit mining are transformed into operational phases that are suitable for extraction through ramp designs. This process is performed with the aid of specialized design software, which is still very manual, time consuming and highly dependent on the expertise of the planner. In this paper, we introduce a new methodology based on a mathematical model to automatically propose the design of ramps from the economic envelope of a pushback, with the resulting envelope having the maximum value. The developed model was tested against a real case scenario showing reasonable and useable solutions for the planner. Using this approach, a planner can evaluate several alternatives in a reasonable time before selecting the final design.
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Abstract

The article undertakes quastion of urban design in a context of urban sprawl linking it to the German debate on suburbanisation, conducted under the slogan of Zwischenstadt – a concept created by Th. Sieverts in 1997. The Ladenburger Kolleg „Zwischenstadt” (LKZ) developed 2002-2006 the interdisciplinary research titled: „Amidst the Edge: Zwischenstadt – towards the qualification of the urbanised landscape” The spatial effects of the dispersion processes were considered to be the manifestation of the creation of a new model of the city. The traditional image of urbanism does not fit its logic. Zwischenstadt (in-beetwen-city) recognized as a phase of the urbanization process, uncoordinated by any imposed urban vision, requires a innovative urban design leitmotives. This new planning tool is necessary to obtain the parameters needed to strengthen internal socio-economic development capabilities. The concept of the efficiency of urban design covered the issue of the character of a city›s image. The morphological studies on a megalopolis structure by Frankfurt a. Main, made a creative use of the Lynch research on the image of the city. Their main goal was to understand the characteristics of the dispersion meant as an urbanized landscape and to determine its susceptibility to the process of improving spatial quality – recognition of the endogenous potentials of generating a Zwischenstadt image.
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Abstract

Waterfront regeneration of port districts emerge as a tool for prestigious development of cities in urban re-imaging and growth. Creation of prestigious housing in these areas are part of a broader strategy of mixed-use and property-led development, but in absence of a holistic approach in planning and design, the urban landscapes may be developed merely on basis of the real estate frameworks. This article looks at how development trends of port cities can take an unintended stance in property-led regeneration of port districts, creating gated communities and failing to succeed in achieving the pre-determined objectives in urban planning. The discussion, which will address to issues of place-making, commodification of public space and planning policies, will take the port city of Izmir as the case. It is suggested that the adoption of a holistic approach to urban planning should guide the regeneration processes and design should take place-making into consideration.
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Abstract

There is estrimated more than 750 (public and privat) hospitals active In Poland. In spite that there is legal regulation concerning hospital projects, realization and equipment – permanent financial problems concerning a public health service, results in standards of hospitals, much worse then represented in hospitals in highly developed countries. A long – term practice of authors, concerning both, design and implementation of hospitals, let them to formulate a set of remarks about disfunction, influalcing growth of a danger, risks and mistakes in medical practice, also unexpected accidents.
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Abstract

The study deals with stability and dynamic problems in bar structures using a probabilistic approach. Structural design parameters are defined as deterministic values and also as random variables, which are not correlated. The criterion of structural failure is expressed by the condition of non-exceeding the admissible load multiplier and condition of non-exceeding the admissible vertical displacement. The Hasofer-Lind index was used as a reliability measure. The primary research tool is the FORM method. In order to verify the correctness of the calculations Monte Carlo and Importance Sampling methods were used. The sensitivity of the reliability index to the random variables was defined. The limit state function is not an explicit function of random variables. This dependence was determined using a numerical procedure, e.g. the finite element methods. The paper aims to present the communication between the STAND reliability analysis program and the KRATA and MES3D external FE programs.
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Abstract

A suitable use of software packages for optimization problems can give the possibility to formulate design problems of robotic mechanical systems by taking into account the several aspects and behaviours for optimum solutions both in design and operation. However, an important issue that can be even critical to obtain practical solutions can be recognized in a proper identification and formulation of criteria for optimability purposes and numerical convergence feasibility. In this paper, we have reported experiences that have been developed at LARM in Cassino by referring to the abovementioned issues of determining a design procedure for manipulators both of serial and parallel architectures. The optimality criteria are focused on the well-recognized main aspects of workspace, singularity, and sti#27;ness. Computational aspects are discussed to ensure numerical convergence to solutions that can be also of practical applications. In particular, optimality criteria and computational aspects have been elaborated by taking into account the peculiarity and constraint of each other. The general concepts and formulations are illustrated by referring to specific numerical examples with satisfactory results.
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Abstract

Water is a strategic material. Recycling is an important component of balancing its use. Deep-bed filtration is an inexpensive purification method and seems to be very effective in spreading water recovery. Good filter designs, such as the fibrous filter, have high separation efficiency, low resistance for the up-flowing fluid and high retention capacity. However, one of the substantial problems of this process is the biofouling of the filter. Biofouling causes clogging and greatly reduces the life of the filter. Therefore, the melt-blown technique was used for the formation of novel antibacterial fibrous filters. Such filters are made of polypropylene composites with zinc oxide and silver nanoparticles on the fiber surface. These components act as inhibitors of bacterial growth in the filter and were tested in laboratory and full scale experiments. Antibacterial/bacteriostatic tests were performed on Petri dishes with E. coli and B. subtilis. Full scale experiments were performed on natural river water, which contained abiotic particles and mutualistic bacteria. The filter performance at industrial scale conditions was measured using a particle counter, a flow cytometer and a confocal microscope. The results of the experiments indicate a significant improvement of the composite filter performance compared to the regular fibrous filter. The differences were mostly due to a reduction in the biofouling effect.
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