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PL
Niniejszy artykuł stanowi pierwszą część cyklu rozważań o idei Circular Economy jako holistycznej strategii, która może wyrażać się w kształtowaniu urbanistyki, architektury – ale też w mniejszej skali – w projektowaniu produktu. Jako wyraz świadomej troski o klimat i dalsze losy naszej planety, a także zdrowie mieszkańców miast, GOZ wytycza nowe oraz niezbędne paradygmaty dla odpowiedzialnego kształtowania budynków i współczesnych miast, korelujących oraz harmonizujących z naturą i cennymi zasobami, bazujące m.in. na kompaktowaniu oraz ograniczaniu transportu, prefabrykacji, wykorzystywaniu sił natury w sprzężeniu z nowymi technologiami. Projektowanie zgodne z doktryną Circular Economy powinno wynikać zarówno z idei projektu, jak i organizacji samego procesu, od koncepcji do realizacji. Architektura oraz design są w tym kontekście pojmowane jako dziedziny interdyscyplinarne, które ściśle się przenikają.
EN
This article is the first part of a series of essays on the different ways the idea of circular economy is implemented in architecture and design, understood as interdisciplinary fields which can overlap in the present. The philosophy of closed circuit, including the principles of sustainable development – implemented both in large-scale architecture and in the industrial design objects – has important elements in common; these are first and foremost expressed in a holistic approach to design. The closed circuit economy model follows the pattern of the natural ecosystem, which is translated into systemic thinking. This simple connection shows that the ideas of circular economy may be directly expressed in the way town planning, architecture and also – though to a lesser extent – product design are shaped. This approach should be systemic and result both from the idea of a project and from the process organization – from concept to realization.
2
EN
Currently, conventional methods of decline development put enormous cost pressure on the profitability of mining operations. This is the case with narrow vein ore bodies where current methods and mine design of decline development may be too expensive to support economic extraction of the ore. According to studies, the time it takes to drill, clean and blast an end in conventional decline development can be up to 224 minutes. This is because once an end is blasted, cleaning should first be completed before drilling can commence, resulting in low advance rates per shift. Improvements in advance rates during decline development can be achieved by application of the Electric Monorail Transport System (EMTS) based drilling system. The system consists of the drilling and loading components that use monorail technology to drill and clean the face during decline development. The two systems work simultaneously at the face in such a way that as the top part of the face is being drilled the pneumatic loading system cleans the face. However, to improve the efficiency of the two systems, critical processes performed by the two systems during mining operations must be automated. Automation increases safety and productivity, reduces operator fatigue and also reduces the labour costs of the system. The aim of this paper is, therefore, to describe automation designs of the two processes performed by the monorail drilling and loading systems during operations. During automation design, critical processes performed by the two systems and control requirements necessary to allow the two systems execute such processes automatically have also been identified.
DE
Derzeit haben konventionelle Methoden der Abnahme Entwicklung enormen Kostendruck auf die Rentabilität der Bergbau. Dies ist der Fall mit engen Vene Erzkörper, wo aktuelle Methoden und Mine Design der Entwicklung des Rückgangs kann zu teuer sein, um die wirtschaftliche Extraktion des Erzes zu unterstützen. Studien zufolge kann die Zeit, die zum Bohren, Reinigen und Sprengen eines Endes in einer konventionellen Abnahmeentwicklung benötigt wird, bis zu 224 Minuten dauern. Dies liegt daran, dass, sobald ein Ende gestrahlt wird, sollte die Reinigung zuerst abgeschlossen werden, bevor das Bohren beginnen kann, was zu niedrigen Vorschüben pro Schicht. Verbesserungen bei den Fortschrittsraten bei der Entwicklung des Rückgangs können durch die Anwendung des Elektrohängebahn-systems (EMTS) erreicht werden. Das System besteht aus den Bohr-und Beschickung Komponenten, die Monorail-Technologie zu bohren und zu reinigen das Gesicht bei der Entwicklung des Rückgangs. Die beiden Systeme arbeiten gleichzeitig am Gesichtsfeld so, dass das pneumatische Ladensystem bei der Bohrung des Oberteils des Gesichts das Gesicht reinigt. Um jedoch die Effizienz der beiden Systeme zu verbessern, müssen kritische Prozesse, die von den beiden Systemen im Bergbau durchgeführt werden, automatisiert werden. Die Automatisierung steigert die Sicherheit und Produktivität, reduziert die Ermüdung des Bedienpersonals und reduziert gleichzeitig die Arbeitskosten des Systems. Das Ziel dieser Arbeit ist es daher, Automatisierungskonzepte der beiden Prozesse zu beschreiben, die von den Monorail-Bohr- und Beschickungssystemen während des Betriebs durchgeführt werden. Während des Automatisierungsentwurfs wurden auch kritische Prozesse identifiziert, die von den beiden Systemen durchgeführt wurden, und Kontrollanforderungen, die erforderlich sind, damit die beiden Systeme solche Prozesse automatisch ausführen können.
3
Content available Closed Loop Supply Chain with Production Planning
EN
We present a Closed Loop Supply Chain (CLSC) model that supports a production planning (PP) process. CLSC model is based on CLSC framework model which consists of four main centers: collection, recovery center, distribution and disposal centers. These logistics parts support main production lines. Some quantity of the products is recovered and the factories don’t need to spend money for production. This is a simple cost reduction process. In CLSC literature one can hardly meet the models of production planning processes supported by CLSC. Important problem with that models is the computational complexity when one wants to prepare production plans for more than one time period. This is connected with a number of the numerical variables of the CLSC and PP models which are usually Integer Programming models solved with Branch & Bound algorithms. We present some modifications of the widely known and used constraints in the CLSC models to optimize solving process. All the experiments were conducted with the CPLEX solver.
EN
This paper presents a closed loop simulation model that represents the mining logistics chain of the Vitória Minas Railway (VMR), Brazil. The simulator includes the loading process, circulation of loaded trains, unloading of ores for external and internal markets and the distribution of empty trains for new loads. General cargo and passengers trains are also included in the model, which, along with the queues formed in the circulation and the preventive and corrective maintenance of rolling stock, tracks and equipment, interfere with the transportation of iron ore. The primary objective of the iron ore transport is to meet the daily loading and unloading schedules and minimize queues by maximizing the operations at the loading and unloading points. The VMR simulator developed uses macro-mesoscopic approach with Monte Carlo simulation. To validate the simulator, we used actual data of the railway and compared with reality. We obtained a very good adhesion to the value of 2.9% for the validation scenario (Scenario 1) and 3.4% for the scenario with reducing the number of lots of wagons (Scenario 2). We concluded with this simulation that it is possible to reduce the number of GDE wagons without reducing the current level of productivity of the rail system.
PT
Este artigo apresenta o modelo de simulação do circuito fechado da rede logística de minério de ferro da ferrovia Vitória Á Minas (VMR), Brasil. O simulador inclui o processo de carregamento, circulação dos trens carregados, descarregamento para os mercados externos e internos e a distribuição dos trens vazios para novos carregamentos. Os trens de carga geral e de passageiros também foram incluídos no modelo, bem como suas filas de formação e as manutenções preventivas e corretivas do material rodante, que interferem no transporte do minério de ferro. O principal objetivo do transporte de minério de ferro é atender as programações de carregamento e descarregamento e minimizar as filas maximizando as operações nos pontos de carregamento e descarregamento. O simulador VMR desenvolvido utiliza uma abordagem macro-mesoscópica de simulação de Monte Carlo. Para validar o simulador, foi utilizado dados da ferrovia e comparado com a realidade. Obtivemos uma aderência muito de 2,9% para o cenário de validação (cenário 1) e 3,4% para o cenário com a redução do número de lotes de vagão (cenário 2). Concluímos que com esta simulação é possível reduz o número de lotes de vagões GDE sem reduzir a produtividade da ferrovia.
5
Content available remote Force generation survey in magnetic shape memory alloys
PL
Przetworniki stosowane w różnego rodzaju urządzeniach zamieniają elektryczny sygnał wejściowy na nieelektryczny, zwykle mechaniczny, sygnał wyjściowy typu: siła, prędkość, przemieszczenie, natężenie przepływu albo ciśnienie. W artykule przedstawiono materiały z magnetyczną pamięcią kształtu, które stanowią nową grupę materiałów inteligentnych i są przedmiotem wielu badań prowadzonych obecnie na świecie. Materiały te zmieniają swoje właściwości (długość, naprężenia wewnętrzne) pod wpływem zewnętrznego pola magnetycznego. We wstępie podano ich opis teoretyczny i cechy szczególne, a także opisano proces produkcji i zasadę działania. Na potrzeby badań skonstruowano demonstracyjny przetwornik elektromagnetyczny, który umożliwia uzyskanie indukcji magnetycznej w szczelinie powietrznej na poziomie 0,7 T. Analizę podstawowej nieliniowości tego materiału, jaką jest histereza, wykonano dla sygnałów sterujących o gasnącej amplitudzie i obu polaryzacji prądu zasilania Następnie podjęto próbę regulacji siły w układzie ze sprzężeniem zwrotnym.
EN
Transducers used in all kinds of devices convert electrical input signal into a non-electrical, usually mechanical output such as: strength, speed, displacement, flow rate or pressure. Different kinds of electric motors and solenoids are commonly used as electromagnetic transducers. In this paper authors present materials with magnetic shape memory, which are a new group of smart material, and are subject to a number of ongoing research in the world. They change own properties (length, internal stress), under an influence of an external magnetic field. Authors placed in an introduction, a theoretical description of material, lists of their most important features, and also described production process and principle of operation. In order to perform research, a demonstration electromagnetic transducer was designed, which is distinguished by magnetic induction in air gap of 0.7 T. Study contains an analysis of the basic nonlinearity of this material, which is hysteresis, made to sinusoidal control signals of fading amplitude for both polarities of input current. Next, authors attempted to adjust strength of closed loop system where measured force was a feedback signal.
6
Content available remote Fuzzy logic controller of the ventilation system
EN
This paper considers the closed loop model of ventilation system with induction motor drive. The Takagi-Sugeno fuzzy logic controller with PD created. Proposed fuzzy logic controller was created using Matlab and function ANFIS (adaptive neuro-fuzzy inference system).The ventilation system model was simulated with three types of different controllers: conventional PI (proportional-integral), PD (proportional-derivative) and Fuzzy logic PD controller. The advantages of created fuzzy logic controller and simulation results of proposed system were presented and analyzed.
PL
W pracy rozpatrzono model systemu wentylacyjnego ze sprzężeniem zwrotnym wykorzystującego silnik indukcyjny. Dla tego systemu stworzono sterownik PD w oparciu o zasady logiki rozmytej (fuzzy logic). Sterownik zrealizowano w środowisku Matlab-Simulink. Przedstawiono i przeanalizowano metodą symulacyjną podstawowe charakterystyki zaproponowanego sterownika.
EN
The paper presents the problem of designing of a fractional order controller satisfying the conditions of gain and phase margins of the closed-loop system with time-delay inertial plant. The transfer function of the controller follows directly from the use of Bode's ideal transfer function as a reference transfer function for the open loop system. Using the classical D-partition method and the gain-phase margin tester, a simple computational method for determining stability regions in the controller parameters plane is given. An efficient analytical procedure to obtain controller parameter values for specified gain and phase margin requirements is also given. The considerations are illustrated by numerical examples computed in MATLAB/Simulink.
EN
The paper describes a compact current sensor developed for power electronics e.g. DC/DC converter as well as drive system application. Basic topology for the sensor in a closed loop technology is described. Optimization of magnetic path of the sensor has been described, which allows, to get lower losses of sensors’ elements. Laboratory tests of a compact current sensor are presented.
PL
Artykuł poświęcony jest kompaktowemu czujnikowi prądu, opracowanemu dla potrzeb energoelektroniki np. przekształtnika DC/DC lub napędu. Opisano podstawową topologię czujnika prądu w układzie kompensacyjnym. Przedstawiono optymalizacje obwodu magnetycznego, który pozwala na zmniejszenie strat w elementach czujnika prądu. Zaprezentowano wyniki badań laboratoryjnych.
9
Content available remote Transient vibration of unsteady linear closed loop systems
EN
A problem if unsteady linear closed loop system vibration is formulated and solved in this paper. Proportional, ideal derivative and delayed feedback interaction is considered. The mixed method of rigid and deformable finite elements is extended by including coupling elements, and applied to modelling the system. An unconditionally stable numerical integration variant of the Newmark method is used for solving the problem. Special computer software is implemented and illustrative calculation of the traverse shaper's model are performed. Time and frequency plots for chosen generalised coordinates of the model and for several cases of the feedback interaction, are obtained as results.
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