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PL
Przedsięwzięcia budowlane to złożone procesy realizowane w dynamicznych środowiskach. Uchwycenie i zrozumienie ich złożoności wymaga myślenia systemowego, według którego przedsięwzięcie interpretowane jest jako zbiór różnych elementów (zadania, ludzie, maszyny, materiały i wiedza) i relacji między nimi. Klasyczne podejście do analizy ryzyka w przedsięwzięciach budowlanych zaniedbuje ocenę złożoności tych systemów i znaczenia ich emergentnych właściwości, takich jak np. podatność na zagrożenia, zdolność do adaptacji czy w konsekwencji odporność systemowa. Stosowanie koncepcji proaktywnego podejścia w planowaniu przedsięwzięć budowlanych wymaga rozwijania metod ilościowych do modelowania takich systemów i analizy wyżej wymienionych właściwości, które są odpowiedzią systemu na ryzyko.
EN
Construction projects are complex processes carried out in dynamic environments. Grasping and understanding their complexity requires the adoption of systems thinking, in which a project is interpreted as a set of various elements (tasks, people, machines, materials and knowledge) and relations between them. The classical approach to risk analysis in construction projects neglects the assessment of the complexity of these systems and the significance of their emergent properties such as vulnerability to threats, adaptability and, consequently, systemic resilience. Using proactive approaches in construction project planning requires the development of quantitative methods of modeling such systems and analysing their abovementioned properties, which are a given system’s response to risk.
EN
Nowadays Information Systems (IS) become more and more distributed, complex, and heterogeneous. Such nature of IS make them or their components a Black Box. Although classical software operates according understandable logic, modern complex software often shows non-determinism in its operation. Artificial Intelligence (AI) based on Artificial Neural Networks (ANN) is an example of such systems. This paper considers IS architecture consisting of 4 components, one of which represents non-determinism as an "Machine Intuition". The architecture is derived from 3-tier computer architecture and based on psychological findings. This approach allowed building a simple and user/developer friendly model. Practical value of the architecture is concluded in ability to better understand, design, and develop the IS containing units with non-deterministic behavior, deal with AI overfitting, underfitting, and threat problems. Architecture and principles represented in this paper can be applied not only to AI/ANN but different IS types.
3
PL
Koncepcja uczenia się organizacyjnego (OL), mimo że ma już za sobą okres wzmożonego wzrostu popularności, nie straciła na aktualności i wadze. Mimo dość długiej historii badań nie istnieje spójna teoria uczenia się organizacyjnego. W pracy dokonano przeglądu czterech podejść do OL: behawiorystycznego, kognitywnego, konstruktywistycznego i społeczno-poznawczego. Ich porównanie z perspektywą nazwaną tu „złożonościową” (czyli związaną z traktowaniem organizacji jako systemu złożonego w rozumieniu teorii złożoności) wspiera tezę o rosnącej akceptacji złożoności w rozwoju teorii uczenia się organizacyjnego.
EN
The organizational learning concept, although no longer in its hype phase, is still considered important and up-to-date. Despite a relatively long history, there is no common theory of Organizational Learning. This paper reviews four approaches to Organizational Learning: behaviourist, cognitive, constructivist, and social-cognitive. Their comparison with the complex (inspired by complexity science) perspective maintains the thesis that there is agrowing acceptance of complexity in the evolution of the Organizational Learning theory.
4
Content available remote Monte Carlo simulation approach to reliability analysis of complex systems
EN
The article presents new results concerned with general procedures and algorithms to assess the reliability of complex systems with various reliability structures. The analytical method and based on it the simulation method were used to estimate the reliability characteristics of the port grain transportation system. Finally, the general simulation algorithm was developed to evaluate the reliability characteristics of ageing complex systems. In this case, the systems operating processes were described by any distributions of sojourn times in operation states and the reliability functions of their components were modified in such a way that these components are not characterized by a "lack of memory". The application of this algorithm has been illustrated by the results for exemplary complex two-state systems.
PL
Artykuł przedstawia nowe wyniki w postaci ogólnych procedur i algorytmów symulacyjnych pozwalających oceniać niezawodność złożonych systemów o różnorodnych strukturach niezawodnościowych. Metody analityczna oraz oparta na niej metoda symulacji zostały zastosowane do oszacowania charakterystyk niezawodności portowego systemu transportu zboża. Ponadto zbudowany został ogólny algorytm pozwalający oceniać niezawodność starzejących się systemów złożonych, których procesy eksploatacyjne opisane są dowolnymi rozkładami czasów przebywania w stanach, natomiast dowolne funkcje niezawodności ich elementów są zmodyfikowane w ten sposób, że elementy te nie charakteryzują się „brakiem pamięci”. Zastosowanie tego algorytmu zostało zilustrowane wynikami dla wybranych złożonych systemów dwustanowych.
EN
Selected issues of component importance analysis for complex technical systems have been presented in this paper. A generic example of a complex technical system and selected statistics of operating losses have been described. A description and diagrams of both qualitative and quantitative importance analysis have also been included. The most significant problems facing complex technical system modelling have been pointed out. A multi-criteria system component importance analysis and the basic criteria for a system component quality evaluation have also been introduced. Some factors influencing the importance of the technical system’s components have also been described. Finally, the necessity of further developing importance analysis methods for machinery operation has been highlighted.
EN
The paper presents the application of cost-based, component-importance measures for complex technical systems. A stern tube sealing system installed on a sea vessel was used as an example of a complex technical system. Selected statistics of a ship’s operation losses were calculated. Selected, known-importance measures were presented and the authors’ own approach to cost-based, component-importance analysis was shown. The following measures were discussed: the operation-interruption cost index, the maintenance potential, the simulation-based maintenance index, and maintenance and operational costs. A description of factors influencing the importance of the technical system components was provided.
7
Content available remote Case study of the complex systems efficiency
EN
The subject of considerations shall be mathematical models describing the fluctuation of states of complex systems. The purpose of this work is to give a defined system (considering failures, the activation process and possibility of repair), its description along with the basic indications of the multi-level system analysis, and in particular the definition of steady-state probabilities and the performance analysis. The modeling tool here are continuous-time Markov chains with finite numer of states.
PL
W pracy przedstawiono model matematyczny systemu technicznego w kontekście analizy funkcjonalnej. Stworzony opis, uwzględniający awarie, proces włączania i możliwości odnowy, pozwala na wyjaśnienie jego działania, uwzględniając probabilistyczny opis przebywania w poszczególnych stanach. Na tej podstawie przeprowadzamy analizę wydajności. Narzędziem modelowania będą łańcuchy markowskie z czasem ciągłym ze skończoną liczbą stanów. Podane przykłady analizy nawiązują do systemu KTZ stosowanego w kopalniach odkrywkowych.
EN
The paper presents the application of cost-based, component-importance measures for complex technical systems. A stern-tube sealing system installed on a sea vessel was used as an example of the complex technical system. Selected statistics of a ship’s operation losses were calculated. Selected, known-importance measures were presented and the authors’ own approach to cost-based, component-importance analysis was shown. The following measures were discussed: the operation-interruption cost index, the maintenance potential, the simulation-based maintenance index, and maintenance and operational costs. A description of factors influencing the importance of the technical system components was provided.
PL
Artykuł przedstawia zastosowanie miar ważności elementów opartych na kosztach eksploatacji dla złożonych systemów technicznych. Jako przykładowy złożony system techniczny poddany analizie wykorzystano uszczelnienie pochwy wału śrubowego statku morskiego. Przedstawiono znane w literaturze ekonomiczne miary ważności oraz zaproponowano wykorzystanie wskaźników opartych na kosztach eksploatacji. W artykule omówiono: wskaźnik kosztu przerwy w użytkowaniu systemu, potencjał obsługi, symulacyjny wskaźnik obsługi, koszty obsługiwania i użytkowania. Przedstawiono czynniki wpływające na ważność elementów systemu technicznego.
EN
The paper presents the application of simulation-based component importance measures for complex technical systems. A stern tube sealing system was installed on a sea vessel as an example of a complex technical system (CTS). Selected statistics of ship operation losses were generated as well as the following measures: the failure criticality index, the downing event criticality index, and the downtime criticality index. A need for further development of the importance analysis methods for machinery operation is exposed and the factors influencing the importance of the technical system components are presented.
PL
Artykuł przedstawia zastosowanie analizy ważności elementów opartej na symulacji w odniesieniu do złożonych systemów technicznych. Jako przykład złożonego systemu technicznego wykorzystano uszczelnienie pochwy wału śrubowego statku morskiego. Wyznaczono wybrane miary statystyczne związane z wyłączeniem statku z użytkowania oraz następujące miary: wskaźnik krytyczności liczby uszkodzeń, wskaźnik krytyczności liczby wyłączeń z użytkowania oraz wskaźnik krytyczności czasu wyłączenia z użytkowania. Przedstawiono potrzeby dalszego rozwoju metod analizy ważności w zastosowaniu dla maszyn i urządzeń. Wskazano czynniki oddziałujące na ważność elementów systemu technicznego.
EN
The paper presents Monte Carlo simulation method applied to the reliability evaluation of a multistate system subjected to a variable multistate operation process. The system operation process model is linked with the system reliability model and proposed to get a general reliability model of the complex system operating at varying in time operation conditions and to find its reliability characteristics. The Monte Carlo simulation algorithm based on the integrated general model of a complex multistate system reliability, linking its reliability model and its operation process model and considering variable at different operation states its reliability structure and its components reliability parameters is applied to the reliability evaluation of port grain transportation system. Next the results of this simulation method application are illustrated and compared with the results obtained by the analytical method.
PL
W artykule opisano budowę systemów współmiejscowych, określono i oszacowano poziomy promieniowanych emisji niepożądanych pochodzących od współczesnego sprzętu informatycznego znajdującego się na rynku Unii Europejskiej. Ponadto w artykule przedstawiono analizę emisji promieniowanej dla poszczególnych interfejsów sprzętowych komputera przenośnego PC oraz wyniki identyfikacji interfejsów sprzętowych dla interfejsów sprzętowych komputera PC cechujących się podwyższoną emisją promieniowaną.
EN
This paper describes the construction of complex systems. This paper defined and estimated levels of radiated emissions coming from the modern computer equipment from the market in the European Union. In addition, the paper presents an analysis of radiated emissions for different hardware interfaces laptop PC and the results of the identification of hardware interfaces for PC hardware interfaces are characterized by increased radiated emissions.
12
EN
The author’s latest monograph “Reliability of large and complex systems” published by Elsevier in 2014 is presented. The paper is composed of an introduction, the monograph contents, conclusions and the references the monograph contents is based on.
EN
In the paper an approach to the reliability analysis of multi-state systems with dependent components operating at variable operation conditions is presented. The multi-state reliability function of complex system is defined and determined for the shipyard rope ship elevator. In developed models, it is assumed that system components have the multi-state exponential reliability functions with interdependent departures rates from the subsets of reliability states.
14
Content available Complex technical systems safety prediction
EN
There are presented general safety analytical models of complex multistate technical systems related to their operation processes. They are the integrated general models of complex technical systems, linking their multistate safety models and their operation processes models and considering variable at the different operation states safety structures and their components safety parameters. The conditional safety functions at the system particular operation states and independent of the system particular operation states the unconditional safety function and the risk function of the complex technical systems are defined. These joint models of the safety and the variable in time system operation processes are constructed for multistate series, parallel, “m out of n”, consecutive “m out of n: F”, series-parallel, parallel-series, series-“m out of k”, “mi out of li”-series, series-consecutive “m out of k: F” and consecutive “mi out of li: F”-series systems. The joint models are applied to determining safety characteristics of these systems related to their varying in time safety structures and their components safety characteristics. Under the assumption that the considered systems are exponential, the unconditional safety functions of these systems are determined. The proposed models and methods are applied to the safety analysis, evaluation and prediction of the one subsystem of the port grain transportation system related to varying in time their operation processes, structures and components safety parameters.
EN
Economic systems as complex systems are the source of many unconventional researches. The actual phenomena in complex systems have the non-scalability features and non-scalability does not exist without the power laws. This paper presents the occurrence of power series of rights and self-similarity in the distribution of national income in 2010, in terms of countries, the European Union and the Polish subregions. This means that one can study economic systems using tools of complex systems theory. This applies especially to the study of the mechanisms governing the system at the local level that generate global action.
16
Content available remote Lokalne sieci bezprzewodowe w kontekście systemów złożonych
PL
Procesy zachodzące w sieciach bezprzewodowych charakteryzują się dużą dynamiką zmian. Z tej perspektywy, przyjęcie tradycyjnego modelu ich opisu bazującego na redukcjonistycznym paradygmacie systemów prostych jest dużym uproszczeniem. Dlatego też, w pracy postaramy się przybliżyć sieci WLAN w ujęciu systemów złożonych. Dodatkowo, zaprezentowane zostaną obszary wykorzystania właściwości sieci dowolnej skali do poprawy funkcjonowania sieci WLAN.
EN
Processes occurring in wireless networks are characterized by dynamic changes. From this perspective, the adoption of the traditional model their description based on a reductionist paradigm of simple systems is a major simplification. Therefore, the WLAN networks in the context of complex systems will be acquainting in this paper. Additionally, areas using properties of free-scale networks will be presented to improve the performance of the WLAN.
17
Content available remote Cellular automata to describe seismicity: a review
EN
Cellular Automata have been used in the literature to describe seismicity. We first historically introduce Cellular Automata and provide some important definitions. Then we proceed to review the most important models, most of them being variations of the spring-block model proposed by Burridge and Knopoff, and describe the most important results obtained from them. We discuss the relation with criticality and also describe some models that try to reproduce real data.
EN
There are presented the methods of the reliability prediction and optimization of complex technical systems related to their operation processes. The general model of the reliability of complex technical systems operating at variable operation conditions linking the semi-Markov modeling of their operation processes with the multistate approach to their reliability analysis and the linear programming are applied in maritime industry to the reliability and risk prediction and optimization of the container gantry crane.
EN
The paper explores the mathematical and computer modeling of complex technical systems related to their operation processes. The complex technical system with the reliability structure and components’ reliability parameters changing at the various operation states is defined. The selected system operation process parameters and the hypothetical distribution functions of the conditional sojourn times at the operation states are defined and identified. The reliability functions of the multistate system and components are introduced and their parameters are identified. The Monte Carlo simulation method is proposed to the complex system reliability evaluation. Moreover, the proposed theoretical and simulation tools are supported with the practical application to the multi-state port oil piping transportation system reliability analysis.
EN
There is presented the IS&RDSS application to the reliability of the improved exemplary complex technical system prediction. There are considered three ways of the exemplary system reliability improvement, a hot single reservation of its components, a cold single reservation of its components and replacing its components by the improved components with reduced intensities of departure from the reliability state subsets. The evaluations of this ways improved exemplary system unconditional multistate reliability function, the expected values and the standard deviations of its unconditional lifetimes in the reliability state subsets and the mean values of its lifetimes in the particular reliability states are performed. Moreover, in the case when the improved system is repairable, its renewal and availability characteristics are estimated.
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