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1
Content available remote An efficient algorithm for 2-dimensional pattern matching problem
EN
Pattern matching is the area of computer science which deals with security and analysis of data. This work proposes two 2D pattern matching algorithms based on two different input domains. The first algorithm is for the case when the given pattern contains only two symbols, that is, binary symbols 0 and 1. The second algorithm is in the case when the given pattern contains decimal numbers, that is, the collection of symbols between 0 and 9. The algorithms proposed in this manuscript convert the given pattern into an equivalent binary or decimal number, correspondingly find the cofactors of the same dimension and convert these cofactors into numbers if a particular cofactor numer matches indicate the matching of the pattern. Furthermore, the algorithm is enhanced for decimal numbers. In the case of decimal numbers, each row of the pattern is changed to its decimal equivalent, and then, modulo with a suitable prime number changes the decimal equivalent into a number less than the prime number. If the number mismatched pattern does not exist, the complexity of the proposed algorithm is very low as compared to other traditional algorithms.
EN
The awareness of the growing importance of the complexity in creating a new type of a modern enterprise strategy and in introducing changes within planning, control and organizational structures contributed to undertaking studies on relationships occurring between the complexity of a modern enterprise and its flexibility in the sector of industrial automation, as well as filling the gap relating to the cognitive impact of poor complexity management on the flexibility of the company. The main objective of the research work is to check whether there is an important relationship between the complexity of the business and its flexibility in the industrial automation sector. Quantification of the relationship between these two quantities – the complexity and flexibility – happened by the use of the Multidimensional Correspondence Analysis (MCA) and Perceptual Maps. The study which has been carried out indicated that the flexibility and complexity functions in the enterprise management rise, however, the knowledge of these issues is highly insufficient. The research discovered that the obstacles which hamper striking a balance between the flexibility and complexity in their advanced stages exert a devastating impact on the quality of the process management. Reducing the flexibility at its higher levels generates a context in which the market risk is enhanced. Companies characterised by improper flexibility management bear higher workforce costs and their processes of decision-making last longer. Methodical and systematized study of flexibility and complexity will decrease the destructive influence of the interaction between these two categories.
3
Content available remote Reductions between certain incidence problems and the continuum hypothesis
EN
In this work, we consider two families of incidence problems, C1 and C2, which are related to real numbers and countable subsets of the real line. Instances of problems of C1 are as follows: given a real number x, pick randomly a countable set of reals A hoping that x ∈ A, whereas instances of problems of C2 are as follows: given a countable set of reals A, pick randomly a real number x hoping that x /∈ A. One could arguably defend that, at least intuitively, problems of C2 are easier to solve than problems of C1. After some suitable formalization, we prove (within ZFC) that, on one hand, problems of C2 are, indeed, at least as easy to solve as problems of C1. On the other hand, the statement “Problems of C1 have the exact same complexity of problems of C2” is shown to be an equivalent of the Continuum Hypothesis.
4
Content available remote Zagadnienie złożoności w teorii architektury końca XX wieku
PL
Postmodernizm podniósł rangę pojęcia złożoności, które stało się kluczowe dla teorii architektury XX wieku. Niezależnie przez pół stulecia rozwijały się interdyscyplinarne nauki o złożoności. Praca śledzi związki obu dziedzin, zwracając uwagę m.in. na wspólne źródła (teorię systemów złożonych Herberta A. Simona, z którego prac korzystali Robert Venturi i Christopher Alexander) oraz teoretyków architektury wyraźnie czerpiących z nauk o złożoności (m.in. Lucien Kroll, Nikos Salingaros).
EN
Postmodernism established the term ‘complexity’ as crucial for the twentieth century theory of architecture. Interdisciplinary complexity sciences developed independently throughout half of the century. The article tracks down relationships between the two, highlighting, among others, common genesis (Herbert A. Simon’s complex systems theory, adopted by Robert Venturi and Christopher Alexander) and theorists depending heavily on complexity sciences (eg. Lucien Kroll or Nikos Salingaros).
EN
Let G be a graph with vertex set V(G), δ (G) minimum degree of G and [formula]. Given a nonempty set M ⊆ V(G) a vertex v of G is said to be k-controlled by M if [formula] where δM(v) represents the number of neighbors of v in M. The set M is called an open k-monopoly for G if it fc-controls every vertex v of G. In this short note we prove that the problem of computing the minimum cardinality of an open k-monopoly in a graph for a negative integer k is NP-complete even restricted to chordal graphs.
EN
Maintenance of process plants requires application of good maintenance practice due to a great level of complexity. From a plant maintenance point of view, the most significant activity is turnaround, an activity carried out through project task with long planning process period and very short execution period, which makes it one of the most complex projects of maintenance in general. It is exactly this kind of maintenance that is based on multidisciplinarity which has to be implemented through the system of quality management on all levels of maintenance management. This paper defines the most significant factors determining the process of turnaround projects quality management and its efficiency. Such relation is observed through moderating influence of complexity on process management efficiency in the turnaround project. The empirical research was conducted based on the survey of turnaround project participants in five refineries in Croatia, Italy, Slovakia and Hungary. For exploring the influence of research variables testing of the target relation is carried out by applying logistical regression. Research results confirm the significance of complexity as variable that significantly contributes to the project performance through the moderating influence on success of the project, as well as the influence of an efficient management on a plant turnaround project key results. Beside theoretical indications, practical implications that arise from this research study mainly refers to management process of the industrial plant maintenance project.
EN
This paper presents a novel low-complexity soft demapping algorithm for two-dimensional non-uniform spaced constellations (2D-NUCs) and massive order one-dimensional NUCs (1D-NUCs). NUCs have been implemented in a wide range of new broadcasting systems to approach the Shannon limit further, such as DVB-NGH, ATSC 3.0 and NGB-W. However, the soft demapping complexity is extreme due to the substantial distance calculations. In the proposed scheme, the demapping process is classified into four cases based on different quadrants. To deal with the complexity problem, four groups of reduced subsets in terms of the quadrant for each bit are separately calculated and stored in advance. Analysis and simulation prove that the proposed demapper only introduces a small penalty under 0.02dB with respect to Max-Log-MAP demapper, whereas a significant complexity reduction ranging from 68.75% to 88.54% is obtained.
EN
The boundedness problem is a well-known exponential-space complete problem for vector addition systems with states (or Petri nets); it asks if the reachability set (for a given initial configuration) is finite. Here we consider a dual problem, the co-finiteness problem that asks if the complement of the reachability set is finite; by restricting the question we get the co-emptiness (or universality) problem that asks if all configurations are reachable. We show that both the co-finiteness problem and the co-emptiness problem are exponential-space complete. While the lower bounds are obtained by a straightforward reduction from coverability, getting the upper bounds is more involved; in particular we use the bounds derived for reversible reachability by Leroux (2013). The studied problems were motivated by a result for structural liveness of Petri nets; this problem was shown decidable by Jančar (2017), without clarifying its complexity. The structural liveness problem is tightly related to a generalization of the co-emptiness problem, where the sets of initial configurations are (possibly infinite) downward closed sets instead of just singletons. We formulate the problems even more generally, for semilinear sets of initial configurations; in this case we show that the co-emptiness problem is decidable (without giving an upper complexity bound), and we formulate a conjecture under which the co-finiteness problem is also decidable.
EN
The article contributes to the discussion on the validity and ways of simplifying modern organisations. There is an increasing focus on simplifying organisations, especially their organisational structures. However, the environment of contemporary organisations is increasingly complex, dynamic and uncertain. Therefore, the postulate of simplicity seems to question Ashby’s law stating that one kind of variety must be balanced by a different kind of variety. To cope with the indicated discrepancy, it is assumed that the simplification of some elements of an organisation is only possible due to the excessive complexity of others. The paper aims to verify the concept of organisational simplexity developed by e Cunha and Rego, which postulates the fit between simple structural solutions, complex workforce and complex environment. However, organisational performance is a factor verifying the legitimacy of the fit. The literature study explored the contradiction inherent in the postulate on the simplification of modern organisations. The contingency theory provided a major framework for the study. The research hypothesis was developed and empirically verified. The empirical study targeted 1142 organisations operating in Poland and Switzerland, different by their industry, size and the form of ownership. To verify the hypothesis, a statistical analysis was carried out, and the multiple correspondence analysis (MCA) method was used. The main result of the critical literature analysis is the finding that theoretical indications for simplifying modern organisations are fragmented, mainly focused on simplifying selected elements of an organisation, not considering the contradiction inherent in the postulate of simplicity related to environmental features and not verified empirically. The notion of the simplexity has been adopted, and it treats the simplicity and complexity as interrelated issues conditioned by situational factors. According to the empirical research results, the fit has been revealed between the degree of structure simplicity, the workforce complexity and the environment features.
EN
One of the mathematical tools to measure the generation rate of new patterns along a sequence of symbols is the Lempel-Ziv complexity (LZ). Under additional assumptions, LZ is an estimator of entropy in the Shannon sense. Since entropy is considered as a measure of randomness, this means that LZ can be treated also as a randomness indicator. In this paper, we used LZ concept to the analysis of different flow regimes in cold flow combustor models. Experimental data for two combustor’s configurations motivated by efficient mixing need were considered. Extensive computer analysis was applied to develop a complexity approach to the analysis of velocity fluctuations recorded with hot-wire anemometry and PIV technique. A natural encoding method to address these velocity fluctuations was proposed. It turned out, that with this encoding the complexity values of the sequences are well correlated with the values obtained by means of RMS method (larger/smaller complexity larger/smaller RMS). However, our calculations pointed out the interesting result that most complex, this means most random, behavior does not overlap with the “most turbulent” point determined by the RMS method, but it is located in the point with maximal average velocity. It seems that complexity method can be particularly useful to analyze turbulent and unsteady flow regimes. Moreover, the complexity can also be used to establish other flow characteristics like its ergodicity or mixing.
PL
W artykule opisuję sześć perspektyw coachingu globalnego. Jego projektodawcą jest Philippe Rosinski, naczelny autorytet w dziedzinie executive i leadership coachingu. Dowodzę, iż każda z wyróżnionych perspektyw (fizyczna, menedżerska, psychologiczna, polityczna, kulturowa i duchowa) dotyka innego, aczkolwiek ważnego aspektu ludzkiego życia. Ponadto wszystkie z wymienionych perspektyw składają się na model holograficzny i realizują w paradygmacie złożoności rzeczywistości VUCA.
EN
The article presents six perspectives of global coaching. Its designer is Philippe Rosinski, the leading authority in the field of executive and leadership coaching. I prove that each of the distinguished perspectives (physical, managerial, psychological, political, cultural and spiritual) affects another, albeit important aspect of human life. In addition, all of these perspectives make up the holographic model and realize in the VUCA complexity paradigm.
12
Content available Ukryte, ale niesamowite – tunele drogowe
PL
Tunele są obiektami, które w zasadzie mają tylko cechy praktyczne. Jeśli inne obiekty będące dziełem inżynierów takie, jak wiadukty czy budynki oprócz własności użytkowych mają również walory estetyczne, to tunele lokują się na drugim końcu tej skali. Co więcej, idąc dalej tym tropem odkrywamy, że każdy tunel jest właściwie przeciwieństwem pojęcia obiektu: to dziura, pustka pod powierzchnią Ziemi. Jednak pomimo tak skrajnie użytkowego charakteru tuneli, można z nimi skojarzyć sporo bardziej abstrakcyjnych zagadnień. W artykule omówiono znaczenie tuneli dla współczesnego społeczeństwa, wspomniano kilka ważnych faktów z ich historii oraz wskazano najważniejsze zagrożenia łączące się z użytkowaniem tuneli.
EN
Tunnels are the objects which in general have only practical features. As far as other objects made by engineers such as viaducts or buildings aside from functional properties have aesthetic values too, the tunnels are located at the opposite end. What is more, it can be revealed that every tunnel is somewhat in contrary to the concept of object: it is just a hole, an empty space under the Earth surface. However, despite such extremely usable characteristic some more abstract ideas can be associated to the tunnels. The paper discusses the importance of tunnels for modern society, some historical facts are mentioned and the most severe dangers connected with tunnels usage are pointed out.
EN
There is no set of constructs or measurement tools in the subject literature that would be widely accepted. In this paper three dimensions of the organisation’s environment namely dynamism, hostility, and complexity, were reviewed. These dimensions are common to most environment research but, especially on the native background, only a few researchers have attempted to synthesize these dimensions in the one research approach. The aim of the paper is synthesis of three dimensions of the organisation’s environment and an empirical verification of whether the existing business practice dimensions of the organisation’s environment correspond to the dimensions laid down and proposed on the theoretical level. In the paper, three dimensions of the organisation’s environment - dynamism, hostility, and complexity were characterised, a research tool developed for measuring them was presented. The approach uses data from a sample of fifty-three new technology-based firms in Poland. Factor analysis was used to explore the viability of these environmental dimensions. The results of the conducted research indicate that the organisation’s environment is a multidimensional construct and could be described by dynamism, hostility and complexity.
EN
One of the main challenges to solve in an Industry 4.0 context for manufacturing leaders worldwide is increasing product and value-stream complexity. In this paper we present a standardized visualization methodology through multichannel plots applied to complex organizational design network configurations. Combining network theory and strategic lean management oriented organizational design through Hoshin Kanri Forest technology, this approach is expected to allow scholars and organizational leaders to systematically visualize strategic organizational design KPI (key performance indicator) dynamic states and hence significantly reduce KPI interpretation complexity. An example is briefly shown for explanatory purposes.
15
Content available Evaluating complicatedness in mechanical design
EN
Few researchers recognize the differences between complexity and complicatedness. Recent research indicates that complexity is an inherent property of the system, and is not a negative attribute. Complicatedness is a design property that can be reduced starting at the design stage. Design solutions for complex systems can be complicated or simple. This study explores the current definitions of complexity and complicatedness. It is concluded that the complicatedness of mechanical design depends on the complexity of design properties such as number of parts and interfaces, manufacturing processes, and assembly. A model for evaluating complicatedness is derived based on these parameters. The derived complicatedness model is the only model to consider both functional and physical attributes as parameters. This model is the main goal of this research. We analyse three sets of functionally equivalent systems to verify the model. We then validate the model with an experiment in which experienced engineers review the designs of these systems and grade the complicatedness of each. Analysis of the results yields a perfect fit for two of the sets. For the third set, in which industrial design is embedded in the mechanical components, the results are inconclusive.
PL
Niewielu naukowców uznaje różnicę pomiędzy złożonością a skomplikowaniem. Jednak ostatnie badania wskazują, że złożoność jest nieodłączną cechą systemu i nie jest to cecha negatywna. Skomplikowanie jest natomiast cechą konstrukcji, która może być zredukowana już na etapie projektowania. Rozwiązania projektowe dla złożonych systemów mogą być skomplikowane lub proste. W prezentowanym artykule analizie zostały poddane definicje złożoności i skomplikowania. Stwierdzono, że skomplikowanie konstrukcji mechanicznych zależy od parametrów projektowych takich jak liczba części i interfejsów, procesów produkcyjnych i montażu. Model oceny skomplikowania oparty jest na tych parametrach. Jest to model, który uwzględnia zarówno funkcjonalne, jak i fizyczne cechy konstrukcji. Opracowanie tego modelu było głównym celem przeprowadzonych badań. Do weryfikacji modelu przeanalizowane zostały trzy zestawy funkcjonalnie równoważnych rozwiązań konstrukcyjnych opracowanych przez niedoświadczonych konstruktorów. Weryfikacja polegała na analizie skomplikowania projektów przez doświadczonych inżynierów, którzy przeglądali projekty tych konstrukcji i oceniali poziom skomplikowania każdego z nich. Analiza wyników pokazała idealne dopasowanie dla dwóch zestawów. Dla trzeciego zestawu, w którym jako elementy mechaniczne wykorzystano rozwiązania przemysłowe, wyniki są niejednoznaczne.
EN
We investigate the variability of one of the most often used complexity measures in the analysis of the time series of RR intervals, i.e. Sample Entropy. The analysis is carried out for a dense matrix of possible r thresholds in 79 24h recordings, for segments consisting of 5000 consecutive beats, randomly selected from the whole recording. It is repeated for the same recordings in random order. This study is made possible by the novel NCM algorithm which is many orders of magnitude faster than the alternative approaches. We find that the bootstrapped standard errors for Sample entropy are large for RR intervals in physiological order compared to the standard errors for shuffled data which correspond to the maximum available entropy. This result indicates that Sample Entropy varies widely over the circadian period. This paper is purely methodological and no physiological interpretations are attempted.
EN
It is realistic to assume that a database management system provides access to the active domain via built-in relations. Therefore, databases that include designated predicates that hold the active domain, which we call product databases, form a natural notion that deserves our attention. An important issue then is to look at the consequences of product databases for the expressiveness and complexity of central existential rule languages. We focus on guarded-based existential rules, and we investigate the impact of product databases on their expressive power and complexity. We show that the queries expressed via (frontier-)guarded rules gain in expressiveness, and in fact, they have the same expressive power as Datalog. On the other hand, there is no impact on the expressiveness of the queries specified via weakly-(frontier-)guarded rules since they are powerful enough to explicitly compute the predicates needed to access the active domain. We also observe that there is no impact on the complexity of the query languages in question.
EN
Diagnosability and opacity are two well-studied problems in discrete-event systems. We revisit these two problems with respect to expressiveness and complexity issues. We first relate different notions of diagnosability and opacity. We consider in particular fairness issues and extend the definition of Germanos et al. [ACM TECS, 2015] of weakly fair diagnosability for safe Petri nets to general Petri nets and to opacity questions. Second, we provide a global picture of complexity results for the verification of diagnosability and opacity. We show that diagnosability is NL-complete for finite state systems, PSPACE-complete for safe convergent Petri nets (even with fairness), and EXPSPACE-complete for general Petri nets without fairness, while non diagnosability is inter-reducible with reachability when fault events are not weakly fair. Opacity is ESPACE-complete for safe Petri nets (even with fairness) and undecidable for general Petri nets already without fairness.
19
Content available remote Universes and simulations: Civilizational development in nested embedding
EN
The rapid development of technology has allowed computer simulations to become routinely used in an increasing number of fields of science. These simulations become more and more realistic, and their energetic efficiency grows due to progress in computer hardware and software. As humans merge with machines via implants, brain-computer interfaces and increased activity involving information instead of material objects, philosophical concepts and theoretical considerations on the nature of reality are beginning to concern practical, working models and testable virtual environments. This article discusses how simulation is understood and employed in computer science today, how software, hardware and the physical universe unify, how simulated realities are embedded one in another, how complicated it can get in application, practical scenarios, and the possible consequences of these situations. A number of basic properties of universes and simulations in such multiply nested structures are reviewed, and the relationship of these properties with a level of civilizational development is explored.
EN
This paper proposes a methodology based on system connections to calculate its complexity. Two study cases are proposed: the dining Chinese philosophers’ problem and the distribution center. Both studies are modeled using the theory of Discrete Event Systems and simulations in different contexts were performed in order to measure their complexities. The obtained results present i) the static complexity as a limiting factor for the dynamic complexity, ii) the lowest cost in terms of complexity for each unit of measure of the system performance and iii) the output sensitivity to the input parameters. The associated complexity and performance measures aggregate knowledge about the system.
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