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Współczesna podziemna eksploatacja złóż surowców mineralnych coraz częściej związana jest z pakietami oprogramowania geologiczno-górniczego, które wspierają prace projektantów od momentu poszukiwania złoża, określenia wielkości jego zasobów, jakości kopaliny, warunków geologicznych, hydrogeologicznych, tektonicznych poprzez planowanie udostępnienia i rozcięcia złoża. P lanowanie produkcji jest jedną z najważniejszych czynności wykonywanych w trakcie prowadzenia projektu górniczego, ponieważ pozwala na założenie konkretnych wyników produkcyjnych kopalni w odniesieniu do jednostki czasu, a następnie umożliwia weryfikację stopnia realizacji zamierzonego planu. Obecnie komputerowe wspomaganie projektowania znajduje zastosowanie do codziennego lub długoterminowego planowania wydobycia z uwzględnieniem ograniczeń złożowych, jakościowych, ilościowych i kosztowych. W artykule przedstawiono wybrane formy złóż rudnych. N a podstawie kilkudziesięciu otworów wiertniczych o długości do 300 m przedstawiono przykładowy fragment modelu rozcięcia złoża rudnego z zastosowaniem komputerowego wspomagania projektowania robót górniczych. Poprzez zastosowanie nowoczesnego programu komputerowego – ABB MineScape o budowie modułowej określono możliwości usprawnienia procesu zagospodarowania przyszłych rejonów eksploatacji. W szczególności przedstawiono rozmieszczenie otworów wiertniczych, na podstawie których wykonano przekroje z przedstawieniem przykładowych miąższości warstw litostratygraficznych, uwzględniając również deformacje nieciągłe w formie uskoków oraz strefy okruszcowane. D la modelu blokowego zostały obliczone zasoby z priorytetem dla metalu nr 1 oraz 2. W ostatniej części artykułu zaproponowano sposób rozcięcia płytko zalegającego złoża rudnego. Stopień wykorzystania złoża określono dla komorowo-filarowego systemu eksploatacji.
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Ilość aktualnie działających szpitali w Polsce szacuje się na ponad 750 (publicznych i prywatnych). Mimo, że projektowanie, realizacja i wyposażenie szpitali jest określone szeregiem aktów prawnych, permanentne problemy finan-sowe publicznej służby zdrowia i niedoinwestowanie powoduje, że nasze szpitale odbiegają od stanu pożądanego i standardu reprezentowanego przez jednostki w krajach wysoko rozwiniętych. Wieloletnia praktyka w projektowaniu i realizacji pozwala na sformułowanie szeregu uwag o najczęściej występujących nieprawidłowościach, wpływających na zwiększenie ryzyka występowania błędów medycznych i zdarzeń niepożądanych.
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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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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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Tematyka niniejszego artykułu dotyczy badań nad specyfiką przeobrażeń współczesnej przestrzeni publicznej miast cywilizacji zachodniej oraz zagadnieniem jej wielopostaciowości. W opisie złożonych przemian przestrzeni miejskich Autorka sięga do zapożyczonych z pola nauk przyrodniczych pojęć „hybrydy” i „hybrydyzacji” szeroko wyjaśniając przy tym zasadność ich wykorzystania we wspomnianym obszarze badawczym.
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Kościół pod wezwaniem Ducha Świętego, zbudowany we Wrocławiu w osiedlu Huby, tworzony był w okresie PRL, co znacznie utrudniało prace projektowe a następnie realizacyjne. Równocześnie był to okres schyłku reżymu komunistycznego, który już musiał się wówczas liczyć z koniecznością pewnej tolerancji religijnej, wymuszonej okolicznościami politycznymi obejmującej też wznoszenie budowli sakralnych. Autor owego kościoła i zarazem autor niniejszego artykułu – wielce aktywny opozycjonista polityczny - był więc zmuszony do jednoczesnego wysiłku i emocji związanych z projektowaniem, przy tym równocześnie był z konieczności wpleciony w zagadnienia formalne i organizacyjne, a w rzeczywistości do stawiania czoła wciąż opierającemu się architekturze sakralnej reżymowi. Autor stara się przybliżyć Czytelnikowi przeżycia związane z tworzeniem tego dzieła. Ostatecznie kościół został pomyślnie zrealizowany i stał się obiektem znanym oraz uznanym.
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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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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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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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The modern companies, which are competing on product market, need to use innovative solutions, in order to become potential leaders. One of the modernization methods is rearrangement of organizational structure and redistribution of competence. The article describes the Advanced Manufacturing Engineering Department in production plant, which is an innovative initiative in worldwide organizational management. Some aspects including AME application in plant processes are highlighted. Some advanced techniques are presented. In the article summary, perspectives for the development of AME are included.
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Design of a compressed air system is a complex issue, involving the design of structures formed by the air sources, air receptors and installations connecting all structure components. Another major task is to ensure the required quality of compressed air. The paper briefly outlines the methodology of integrated and network structure design, using an objective function to find the optimal solution. In terms of quality assurance, the technological aspects of compressed air generation, treatment and distribution are defined.
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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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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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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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In the present work, the performance of multilayer coated carbide tool was investigated considering the effect of cutting parameters during turning of 34CrMo4 Low alloy steel. It has high strength and creep strength, and good impact tenacity at low temperature. It can work at –110°C to 500°C. And EN 10083-1 34CrMo4 owns high static strength, impact tenacity, fatigue resistance, and hardenability; without overheating tendencies. The objective functions were selected in relation to the parameters of the cutting process: surface roughness criteria. The correlations between the cutting parameters and performance measures, like surface roughness, were established by multiple linear regression models. Highly significant parameters were determined by performing an Analysis of variance (ANOVA). During the experiments flank wear, cutting force and surface roughness value were measured throughout the tool life. The results have been compared with dry and wet-cooled turning. Analysis of variance factors of design and their interactions were studied for their significance. Finally, a model using multiple regression analysis between cutting speed, fee rate and depth of cut with the tool life was established.
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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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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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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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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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In the paper an application of evolutionary algorithm to design and optimization of combinational digital circuits with respect to transistor count is presented. Multiple layer chromosomes increasing the algorithm efficiency are introduced. Four combinational circuits with truth tables chosen from literature are designed using proposed method. Obtained results are in many cases better than those obtained using other methods.
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The development of a novel design for the toothed segment of drive transmission in longwall shearer is expected to significantly reduce the cost of individual components of the feed system and the related work of repair and renovations, increasing at the same time the safety of mine repair teams. The conducted experimental and numerical analysis of the state of stress and strain in the innovative design of the toothed segment has enabled estimating the maximum effort of the developed structure. Based on the results of fundamental mechanical studies of the cast L20HGSNM steel and fatigue tests combined with the numerical stress/strain analysis, the fatigue life curve was plotted for the examined casting of the rack.
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The aim of this paper was to demonstrate the feasibility of using a Computational Fluid Dynamics tool for the design of a novel Proton Exchange Membrane Fuel Cell and to investigate the performance of serpentine micro-channel flow fields. A three-dimensional steady state model consisting of momentum, heat, species and charge conservation equations in combination with electrochemical equations has been developed. The design of the PEMFC involved electrolyte membrane, anode and cathode catalyst layers, anode and cathode gas diffusion layers, two collectors and serpentine micro-channels of air and fuel. The distributions of mass fraction, temperature, pressure drop and gas flows through the PEMFC were studied. The current density was predicted in a wide scope of voltage. The current density – voltage curve and power characteristic of the analysed PEMFC design were obtained. A validation study showed that the developed model was able to assess the PEMFC performance.
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