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Number of results: 58
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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 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

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 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

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

Zinc plant residue is a hazardous waste which contains high quantity of nickel and other valuable metals. Process parameters such as reaction time, acid concentration, solid-liquid ratio, particle size, stirring speed and temperature for nickel extraction from this waste were optimized using factorial design. Main effects and their interactions were obtained by the analysis of variance ANOVA. Empirical regression model was obtained and used to predict nickel extraction with satisfactory results and to describe the relationship between the predicted results and the experiment results. The important parameters for maximizing nickel extraction were identifi ed to be a leaching time solid-liquid ratio and acid concentration. It was found that above 90% of nickel could be extracted in optimum conditions.
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Abstract

The box wing system is an unconventional way to connect the lifting surfaces that the designers willingly to use in prototypes of new aircrafts. The article present a way to quickly optimize the wing structure of box wing airplane that can be useful during conceptual design. At the beginning, there is presented theory and methods used to code optimization program. Structure analysis is based on FEM beam model, which is sufficient in conceptual design. Optimization is performed using hybrid method, connection of simple iteration and gradient descent methods. Finally, the program is validated by case study.
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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

City is a formal expression of social relations. It is a kind of ethos and dreams connected with history and identity of individuals. It is a structure with thousands of meanings. The opportunities it creates can lead to an outstanding civilization. At the same time it reveals all negative aspects of living. City is a collection of separate individuals combined with common perception of spatial affi liation and identity development. It is worth writing about city because despite its well-defi ned value it is an elusive being. In spite of being a kind of collective needs it is still on the move, transforms all the time reflecting human emotions. Existence of city as a phenomena itself is a symbol of realization of people’s most basic needs and the history of its development shows growing complication and diversification of expectations related to it. City along with is diversity reflects human beings of a particular time. It is a spotlight in which both successes and failures of communities and individuals in each epoch can be seen. Thanks to its interdisciplinary character it can be perceived as multidimensional place. It is a multifaceted organism with high hopes and unlimited opportunities. Differences in perception which are due to a number of its users results in a wide range of problems and expectations. Expectations of local communities and individuals of a whole city vary. As a result, what we call a city landscape must be very vague and differs depending on a particular field which is taken into consideration. The number of opportunities and city-related issues is infi nite. In the dissertation below, however, three factors are the crucial ones: structure, meaning and city phenomena as a landscape. Thanks to the interpretation of model and genius loci as well as defining social expectations we have managed to conceive the phenomena of spatial identity. We have decided on this method referring directly to the concept of landscape. City is in here widely defined between urban aspects of landscape and city landscape. We have tried to understand what city is in terms of landscape, where it comes from and where it goes to. It is a trial of translation the Gaugin’s method: where are we from? Who are we? Where are we going to? into the language of present perception of some particular aspects of town planning. We live at times of the unprecedented technological change which is followed by a social change. It all must have an impact on how city is perceived, what it looks like, how it is to live there and what it is going to be like – what the future has in store. We have tried to bring the reader’s attention to the problems and issues which had appeared before the advent of reality we live in. We have focused on what may have led to a kind of city crisis at the edge of 19th and 20th centuries and some radical solutions trying to overcome the arisen problems and its consequences today. Both its pompous character and sentimentalism of town planning and architecture in the early 20th century have made us be bored with form which is felt in many parts of the world even today. Another aspect of our work covers understanding city in social terms as well as contemporary and future solutions. We are of the opinion it is worth asking questions referring to the future and at the same time regarding its current state and recent past. It is commendable to look for particular tools and solutions. Three dimensions which are covered by the book are figurative. Structure – which is everything we perceive as a kind of a template, identifi cation – we assign to city. It is responsible for recognition, adaptation to some forms by which we defi ne space. Meaning is a step forward. While the structure’s equivalent is „I can see”, the meaning equals to „I know”. Meaning does not exist as a city without structure just like structure does not exist without meaning. Things don’t just exist, they have some characteristics and purpose and it refers to trees, buildings and all other urban elements constituting city in all steady and temporary aspects and time dimensions. Meaning is also interpretation and emotion regarding both community and individual. It is the answer to the question „why?” Some particular places and spaces are linked to some particular values which identify them. This system of values is a must to be able to interpret what space we are dealing with and its diagnosis. Meaning is very much about social aspect too. It has to do with perception and remembering city and it is connected with knowledge, tradition and culture of places. Another aspect linked to relations in city landscape combines other aspects and constitutes something to which city refers to. Phenomena is contribution and verifi cation. The way city works is fundamental to all city residents and users. A key to such understanding a city is the term of genius loci. By singling out objects, order, time, character and light we are able to widely identify essence of space and particular places. The graphic model by Panofsky acts here as a verifying tool. City landscape as a form is of great importance here. The sense of beauty is as essential as the way the city works. Social perception of city is not only shaped by the way it is used, but also by the fact what city is like and how it is perceived. Spatial order is an incredibly important factor understood here as everything what accommodates vaguely defi ned beauty and what is connected with its particular structure, history and identity. All these factors contribute to the value of city landscape. When it comes to city landscape studies social aspect is emphasized by the impact of humanities, especially sociology, which perfectly shows expectations related to space. Cities are built and seen in the context of particular tradition, culture and history. Their skyline and ways of functioning are embedded in mentalities of societies which they represent. Despite their diversity from the global point of view they are susceptible to similar trends resulting in crisis or prosperity periods. They are economic archetypes of success.
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Abstract

This article reflects on the results the use and eff ectiveness of design coding as urban design / development tool, focusing on the roles of and the relationships between the different actors playing parts in the in the design coding process: the administration, the investors, the designers, the politics and the community. It reveals the gap in professional circles that impacts the development process, which, deepened by the continuous battle between the creative, the market-driven and the regulatory modes praxis. The article is polemical in that it points to the three main parties of this collective process, referring to is as the creative, market and regulatory tyranny. The author proposes that design coding, if used correctly, could be an effective tool regulating the essentials of urbanism, leaving room for creativity and enhanced market value. Design coding as such results in improvement of the quality of both urbans space and housing architecture.
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Abstract

The article describes the design principles, the course of work on the project and the implementation of the Nowe Żerniki district, in the context of the theory of sustainable housing complexes. By comparing the settlement to the Aspern Seestadt, which is considered to be the leading European example of new district development, the author tries to find out, if Nowe Żerniki meets the latest European urban standards and can be called innovative on a European scale. Not only the final shape of the settlement was assessed, but also the design process and functional assumptions of the estate.
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Abstract

We study an elegant snap system with only one nonlinear term, which is a quadratic nonlinearity. The snap systemdisplays chaotic attractors,which are controlled easily by changing a system parameter. By using analysis, simulations and a real circuit, the dynamics of such a snap system has been investigated. We also investigate backstepping based adaptive control schemes for the new snap system with unknown parameters.
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Abstract

The chuch dedicated to The Holy Spirit, erected in Wrocław, in housing estate Huby, was created during the communist period, hence it was very difficult to design it, and to build. But it was also the period close to the collapse of this regime, so communist leaders were pressed to be more tolerant towards human rights than before, including the religious freedom and towards building new churches. The author of the church mentioned – a very active political oppositionist – when designing the strongly innovative church building, was simultaneously forced by fate to fight formal difficulties caused by oppressive rulers. Author makes the reader closer to those complicated double troubles: artistic, parallel to the political. Finally, the church building was happily completed, then became widely popular and accepted.
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Abstract

This work examines the reduced-cost design optimization of dual- and multi-band antennas. The primary challenge is independent yet simultaneous control of the antenna responses at two or more frequency bands. In order to handle this task, a feature-based optimization approach is adopted where the design objectives are formulated on the basis of the coordinates of so-called characteristic points (or response features) of the antenna response. Due to only slightly nonlinear dependence of the feature points on antenna geometry parameters, optimization can be attained at a low computational cost. Our approach is demonstrated using two antenna structures with the optimum designs obtained in just a few dozen of EM simulations of the respective structure.
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Abstract

In this paper, a novel structure of a compact UWB slot antenna and its design optimization procedure has been presented. In order to achieve a sufficient number of degrees of freedom necessary to obtain a considerable size reduction rate, the slot is parameterized using spline curves. All antenna dimensions are simultaneously adjusted using numerical optimization procedures. The fundamental bottleneck here is a high cost of the electromagnetic (EM) simulation model of the structure that includes (for reliability) an SMA connector. Another problem is a large number of geometry parameters (nineteen). For the sake of computational efficiency, the optimization process is therefore performed using variable-fidelity EM simulations and surrogate-assisted algorithms. The optimization process is oriented towards explicit reduction of the antenna size and leads to a compact footprint of 199 mm2 as well as acceptable matching within the entire UWB band. The simulation results are validated using physical measurements of the fabricated antenna prototype.
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Abstract

This paper studied the concept of the habitability of buildings as a sustainability factor in the living environment, particularly in the city of Bogotá. The habitability factor stems from the relationship between human beings, the cultural dimension and the environment. Thus, we can say that the habitability factor is an important element in the building design process. Currently in Bogotá there are buildings that do not meet the requirements of the population. In Bogotá only 40% of buildings are of a good quality and a great number of newly produced buildings have made for lower quality living spaces. Consequently, it is important to give an adequate response to these kinds of demands. For thase reasons, this study created a model to evaluate the habitability factor of buildings. This model gives some guidelines for designing sustainable buildings and implementing stategies to design a better urban habitat. Finally, the Habitability model was tested as a pilot in the Primero de Mayo neighbourhood, which is located in the fourth district of Bogotá. The neighbourhood was classified as a cultural heritage site by city hall.
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Abstract

In the recent years, chaotic systems with uncountable equilibrium points such as chaotic systems with line equilibrium and curve equilibrium have been studied well in the literature. This reports a new 3-D chaotic system with an axe-shaped curve of equilibrium points. Dynamics of the chaotic system with the axe-shaped equilibrium has been studied by using phase plots, bifurcation diagram, Lyapunov exponents and Lyapunov dimension. Furthermore, an electronic circuit implementation of the new chaotic system with axe-shaped equilibrium has been designed to check its feasibility. As a control application, we report results for the synchronization of the new system possessing an axe-shaped curve of equilibrium points.
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Abstract

The article discusses the weldment to casting conversion process of rocker arm designed for operation in a special purpose vehicle to obtain a consistency of objective functions, which assume the reduced weight of component, the reduced maximum effort of material under the impact of service loads achieved through topology modification for optimum strength distribution in the sensitive areas, and the development of rocker arm manufacturing technology. As a result of conducted studies, the unit weight of the item was reduced by 25%, and the stress limit values were reduced to a level guaranteeing safe application.
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Abstract

The paper analyzes, from the geometrical aspect, the quality of the new flux cored wire intended for cladding process in function of changes in cladding parameters such as welding speed, coefficient of thermal conductivity, power source setting, the length of projecting portion of the electrode. The results of bead geometry analysis allows to illustrate the nature of the impact of the examined input variables on parameters of generated surface. The most important parameters here are the depth of penetration and the height of clad. The experimental data were processed using the Plackett-Burman experiment, which describes the impact of technological parameters on the main parameters used during production of resisting panels. It shows mathematical relations describing correlations between the input parameters and the value of depth of penetration and hight of bead made by Flux Cored Arc Welding (FCAW).
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Abstract

Simulation software can be used not only for checking the correctness of a particular design but also for finding rules which could be used in majority of future designs. In the present work the recommendations for optimal distance between a side feeder and a casting wall were formulated. The shrinkage problems with application of side feeders may arise from overheating of the moulding sand layer between casting wall and the feeder in case the neck is too short as well as formation of a hot spot at the junction of the neck and the casting. A large number of simulations using commercial software were carried out, in which the main independent variables were: the feeder’s neck length, type and geometry of the feeder, as well as geometry and material of the casting. It was found that the shrinkage defects do not appear for tubular castings, whereas for flat walled castings the neck length and the feeders’ geometry are important parameters to be set properly in order to avoid the shrinkage defects. The rules for optimal lengths were found using the Rough Sets Theory approach, separately for traditional and exothermic feeders.
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Abstract

The Lublin region has a rich history of coexistence and interpenetration of different traditions, cultures and religions, witnessed by its cities and towns. Small towns of the Lublin region are now facing a variety of spatial problems which are related to, among others, the organization and revitalization of public spaces, progressive scattering of housing development or changes in the organisation of traffic. The aim of this article is to present problems connected with landscape design and the revitalization of small towns of the Lublin region as exemplified by Frampol.
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Abstract

In recent years, due to the growing importance of eco-design and tightening EU regulations entrepreneurs are required to implement activities related to environmental protection. It influences the development of methods and tools enabling the implementation of eco-design into practice, which are increasingly used by modern information technologies. They are based on intelligent solutions that allows them to better match the requirements of designers and allows for the automation of processes, and in some cases they are able to do the work themselves, replacing designers. Details are useful in areas that require calculations, comparisons and making choices, which is the process of eco-design. The paper describes methodology of pro-ecological product design oriented towards recycling, based on agent technology, enables the design of environmentally friendly products including recycling. The description of the methodology was preceded by a literature analysis on the characteristics of tools supporting eco-design and the process of its development was presented. The proposed methodology can be used at the design stage of devices to select the best product in terms of ecology. It is based on the original set of recycling indicators, used to evaluate the recycling of the product, ensure the ability to operate in a distributed design environment, and the use of data from various CAD systems, allows full automation of calculations and updates (without user participation).
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