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1

Development of the analytical model and methodof optimization of the priority service corporate computer "Elections" network

Huseynov Zakir Nasib

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2025

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T. 15, nr 2

90--93

EN

The main objective of this article is to provide recommendations for improving the quality of service indicators in priority service corporate computer networks, including the probability ofdenial of service attacks, the probability of timely and losslessinformation delivery, and the selection and effective use of equipment that meets modern requirements.

PL

Głównym celem tego artykułu jest przedstawienie zaleceń dotyczących poprawy wskaźników jakości usług w korporacyjnych sieciach komputerowych z usługami priorytetowymi, w tym prawdopodobieństwa ataków typu "odmowa usługi", prawdopodobieństwa terminowego i bezstratnego dostarczania informacji oraz wyboru i efektywnego wykorzystania sprzętu spełniającego współczesne wymagania.

2

Non-parametric comparison of survival functions with censored data: A computational analysis of greedy and Monte Carlo approaches

Štěpánek Lubomír, Habarta Filip, Malá Ivana, Marek Luboš

Annals of Computer Science and Information Systems

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2024

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Vol. 39

725--730

EN

Comparison of two survival functions, which describe the probability of not experiencing an event of interest by a given time point in two different groups, is a typical task in survival analysis. There are several well-established methods for comparing survival functions, such as the log-rank test and its variants. However, these methods often come with rigid statistical assumptions. In this work, we introduce a non-parametric alternative for comparing survival functions that is nearly free of assumptions. Unlike the log-rank test, which requires the estimation of hazard functions derived from (or facilitating the derivation of) survival functions and assumes a minimum number of observations to ensure asymptotic properties, our method models all possible scenarios based on observed data. These scenarios include those in which the compared survival functions differ in the same way or even more significantly, thus allowing us to calculate the p-value directly. Individuals in these groups may experience an event of interest at specific time points or may be censored, i.e., they might experience the event outside the observed time points. Focusing on all scenarios where survival probabilities differ at least as much as observed usually requires computationally intensive calculations. Censoring is treated as a form of noise, increasing the range of scenarios that need to be calculated and evaluated. Therefore, to estimate the p-value, we compare a greedy approach that computes all possible scenarios in which groups' survival functions differ as observed or more, with a Monte Carlo simulation of these scenarios, alongside a traditional approach based on the log-rank test. Our proposed method reduces the first type error rate, enhancing its utility in studies where robustness against false positives is critical. We also analyze the asymptotic time complexity of both proposed approaches.

3

Real time quantum tunneling through a double square barier

Papadopoulos George J.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2023

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Vol. 27, No 3

1--8

EN

The propagator of a one-dimensional double square barrier is obtained analytically in terms of the relevant eigenfunctions. With the aid of the propagator the wavefunction evolution for a particle, initially in a state of wave packet, located on the left-hand side of the barrier, with ignorable overlap with the barrier, is obtained. There follows study of the probability and current densities stemming from the particle initial state. In particular, the space distribution sat given times of the above densities are given. Furthermore, their evolution in time at the entrance and exit of the barrier is obtained. The numerical results show repeated reversal in the current density at the barrier entrance, while being unidirectional at the exit. However, the probability of entering the barrier over an extremely long time tends to equal the corresponding probability of exiting the barrier. Owing to the fact that the wave packet expands on both of its sides, as time goes by, it is possible to have transmission even if the particle’s initial momentum points away from the barrier. The effect, in question, becomes evident in diagrams for the transmitted probability beyond the barrier exit in terms of the particle initial momentum, over a region.

4

Wybrane aspekty analizy i oceny ryzyka zagrożeń bezpieczeństwa narodowego

Kupiński Jerzy, Keplin Jarosław

Rocznik Bezpieczeństwa Morskiego

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2023

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R. XVII

319--350

PL

Celem artykułu jest próba przedstawienia Czytelnikowi koncepcji analizy i oceny ryzyka zagrożeń bezpieczeństwa narodowego. Obecnie zapewnienie bezpieczeństwa państwa na pożądanym poziomie jest działaniem coraz bardziej złożonym, z uwagi na ryzyko wystąpienia nowych zagrożeń w niestabilnym środowisku bezpieczeństwa międzynarodowego. Sytuacja taka wymaga od państw sprostania wielu wyzwaniom, a jednym z nich jest nabywanie odporności państwa na współczesne zagrożenia i dokonanie poprawnej analizy w przypadku zidentyfikowanych oraz prognozowanych zagrożeń. Aby być odpornym na współczesne zagrożenia, istotnym jest wiedza na temat prawdopodobieństwa ich wystąpienia oraz określenie ich skutków. W materiale badawczym wykorzystano wybrane normy i standardy pozwalające na określenie ryzyka w gospodarce rynkowej, finansów państwa, w przedsiębiorstwach, a także z innych dziedzin. Pomimo tego, iż te normy i standardy charakteryzują się odmiennym stopniem złożoności struktury i zależne są od różnych czynników, to stanowiły one koncepcję dla nowego podejścia w zakresie przyjętego celu niniejszego opracowania.

EN

The aim of the article is to present the new concept of risk assessment and analysis of threats to national security. Currently, ensuring the state security at the desired level is an increasingly complex activity, due to the risk of new threats in the unstable international security environment. This situation requires countries to meet many challenges, and one of them is the resilience to modern threats and making a correct analysis in the case of identified and forecasted threats. To be resilient to modern threats, it is important to know about the likelihood of their occurrence and determine their effects. The research material uses selected norms and standards that allow to determine the risk in the market economy, state finance, as well as in other fields. Despite the fact that these norms and standards are characterized by a different structure of complexity and depend on various factors, they constituted a concept for a new approach in terms of the objective of this study.

5

Ryzyko podtopień sieci kanalizacyjnych spowodowanych występowaniem osadów w kanałach

Kuliczkowska Emilia

Instal

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2023

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nr 6

42--46

PL

Zaproponowano metodę wyznaczania ryzyka podtopień sieci kanalizacyjnych spowodowanych wystąpieniem osadów w kanałach. Podano przyczyny występowania podtopień przewodów kanalizacyjnych. Zamieszczono wyniki badań CCTV wykonanych przez Politechnikę Świętokrzyską, dotyczących występowania osadów kanalizacyjnych w kanałach betonowych, kamionkowych i wykonanych z rur PVC wraz z propozycją ilościowej ich oceny. Ustalono kategorie prawdopodobieństwa podtopień przewodów kanalizacyjnych, kategorie konsekwencji wystąpienia awarii oraz miary ryzyka podtopienia przewodów kanalizacyjnych.

EN

A method of determining the risk of flooding of sewer pipelines caused by the occurrence of deposits in sewers has been proposed. The causes of flooding of sewage pipes were listed. The results of CCTV studies carried out by the Kielce University of Technology on the occurrence of sewer deposits in concrete, vitrified clay and PVC pipes, together with a proposal for their quantitative assessment, are given. Probability categories of flooding of sewer pipelines, categories of failure consequences and the risk of flooding of sewer are determined.

6

Modeling and analysis of the characteristics of multichannel and multi-node computer networks with priority service

Huseynov Zakir Nasib, Mammadov Mahil Isa, Ismayilov Togrul Atabay

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2023

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T. 13, nr 2

74--77

EN

The subject of the research is modeling and analysisof the characteristics of multichannel and multi-node computer networks with priority services. The work is devoted to the study of the qualitative indicators of the functioning of computer networks with priority service.In this work, mathematical modelsare developed that make it possible to assess the quality of functioning of modern computer networks, taking into account thenumber of channels, waiting places in network nodes and the number of network nodes. The proposed methods for calculating the probability of failures andthe probability of timely delivery of a stream of requests make it possible to determine the real values of the qualitative indicators of the functioningof computer networks and are suitable for both designed and operating computer networks. The proposed technique makes it possible to determinethe number of packets in the queue and the optimal amount of buffer memory in computer network nodes.

PL

Przedmiotem badań jest modelowanie i analiza charakterystyk wielokanałowych i wielowęzłowych sieci komputerowych z usługami priorytetowymi. Praca poświęcona jest badaniu jakościowych wskaźników funkcjonowania sieci komputerowych z usługami priorytetowymi. W pracy opracowano modele matematyczne umożliwiające ocenę jakości funkcjonowania nowoczesnych sieci komputerowych z uwzględnieniem liczby kanałów, miejsc oczekiwania w węzłach sieci oraz liczby węzłów sieci. Proponowane metody obliczania prawdopodobieństwa awarii i prawdopodobieństwa terminowego dostarczenia strumienia żądań umożliwiają określenie rzeczywistych wartości wskaźników jakościowych funkcjonowania sieci komputerowych i są odpowiednie zarówno dla projektowanych, jak i działających sieci komputerowych. Proponowana technika umożliwia określenie liczby pakietów w kolejce i optymalnej ilości pamięci buforowej w węzłach sieci komputerowej.

7

Probability to possibility transformation as a way to standardize description of systematic and randoms errors

Urbański Michał, Wójcicka Kinga, Wójcicki Paweł

Przegląd Elektrotechniczny

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2022

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R. 98, nr 12

159--162

EN

From the point of view of the probabilistic model, measurement is described as a selection from sample set (set of elementary events). In the framework of fuzzy variable approach the possibility measure describes the degree of adjustment of the standards to the object being measured. On the other side fuzzy approach is better than probabilistic to describe the measurement process. To comply with the GUM recommendations, a transformation of probability to possibility is proposed, in which expanded uncertainty is maintained. In this way, both types of uncertainties are determined within one fuzzy model.

PL

Z punktu widzenia modelu probabilistycznego pomiar opisujemy jako losowanie ze zbioru zdarzeń elementarnych. Pomiar w języku zbiorów rozmytych można opisać jako proces dopasowania do mierzonego obiektu odpowiedniego wzorca. Miarą jakości dopasowania jest stopień zgodności tego dopasowania. W celu stworzenia modelu zgodnego z rekomendacją Przewodnika Wyrażania Niepewności Pomiaru proponujemy transformację rozkładu prawdopodobieństwa na funkcję przynależności zbioru rozmytego zachowującą niepewność typu A. W ten sposób oba rodzaje niepewności opisuje się jednym modelem z miarą rozmytą.

8

Computation of steady-state probabilities of the states of the SMP model in Beacon Message Dissemination

Wilfred C. Bazil, Selvarathi M.

Przegląd Elektrotechniczny

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2022

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R. 98, nr 4

16--20

EN

With the advent of the latest technologies like AI, IoT, LiDAR systems and ToF techniques, smart cars have become a reality. Communication between machines has become possible thereby the cars on the road communicate among themselves, with the driver and with the things outside the road. Beacon messages are the most important messages, which need the highest priority and accuracy in communication. An SMP model is designed to understand and evaluate the broadcast procedure of the beacon messages. We derive the steady state probabilities of the states of the SMP according to the transmission protocol.

PL

Wraz z pojawieniem się najnowszych technologii, takich jak AI, IoT, systemy LiDAR i techniki ToF, inteligentne samochody stały się rzeczywistością. Komunikacja między maszynami stała się możliwa, dzięki czemu samochody na drodze komunikują się między sobą, z kierowcą iz rzeczami znajdującymi się poza drogą. Komunikaty Beacon to najważniejsze komunikaty, które wymagają najwyższego priorytetu i dokładności w komunikacji. Model SMP został zaprojektowany w celu zrozumienia i oceny procedury rozgłaszania komunikatów nawigacyjnych. Wyprowadzamy prawdopodobieństwa stanów ustalonych stanów SMP zgodnie z protokołem transmis.

9

Suddenly loaded arrays of pillars with variable range of load transfer

Derda Tomasz

Journal of Applied Mathematics and Computational Mechanics

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2022

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Vol. 21, nr 4

16--27

EN

This paper deals with multicomponent systems subjected to suddenly applied loads. Such multicomponent systems consist of functionally identical elements, but the elements differ in their ability to sustain the applied load. Specifically, arrays of pillars are an example of the multicomponent systems. The capability of the array to sustain the applied load depends not only on the strength of the pillars but also on how the load coming from failed pillars is redistributed to the intact ones. We employ a Fiber Bundle Model with load transfer restricted within a rectangular region generated dynamically after each pillar’s destruction. We investigate strength of the array and its survivability.

10

Probabilistic assessment of the seismic vulnerability of a rammed earth construction: a case study

Jama Balil, Agliz Driss, Abderrahman Atmani, Derife Mina

Archives of Civil Engineering

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2022

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Vol. 68, nr 2

325--335

EN

Rammed earth significantly reduces intrinsic energy compared to concrete construction and has an environmental benefit throughout the life cycle of the building: phases of construction, operation, maintenance, renovation, and demolition. Several studies have recently been carried out to study this material. However, the seismic behavior of rammed earth constructions is still an important topic that needs to be studied in more detail. Through the analysis of non-linear behavior of the rammed earth construction for different wall thicknesses according to the Moroccan earthquake regulation RPS2011, we were able to assess the seismic performance under the corresponding conditions (loads, seismic zone). The results show that the walls studied can have good resistance in areas of seismicity ranging from “very low” to “moderate” and acceptable performance in areas of high seismicity. Furthermore, fragility analysis shows that rammed construction with a wall thickness equal to 50 centimeters exhibits better seismic performance and a low probability of damage, particularly in the case of moderate, severe, and complete damage states.

11

A short note on post-hoc testing using random forests algorithm: Principles, asymptotic time complexity analysis, and beyond

Štěpánek Lubomír, Habarta Filip, Malá Ivana, Marek Luboš

Annals of Computer Science and Information Systems

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2022

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Vol. 30

489--497

EN

When testing whether a continuous variable differs between categories of a factor variable or their combinations, taking into account other continuous covariates, one may use an analysis of covariance. Several post-hoc methods, such as Tukey’s honestly significant difference test, Scheffé’s, Dunn’s, or Nemenyi’s test are well-established when the analysis of covariance rejects the hypothesis there is no difference between any categories. However, these methods are statistically rigid and usually require meeting statistical assumptions. In this work, we address the issue using a random forest-based algorithm, practically assumption-free, classifying individual observations into the factor’s categories using the dependent continuous variable and covariates on input. The higher the proportion of trees classifying the observations into two different categories is, the more likely a statistical difference between the categories is. To adjust the method’s first-type error rate, we change random forest trees’ complexity by pruning to modify the proportions of highly complex trees. Besides simulations that demonstrate a relationship between the tree pruning level, tree complexity, and first-type error rate, we analyze the asymptotic time complexity of the proposed random forest-based method compared to established techniques.

12

Vibrations of a low-frequency floor under various pedestrian loading scenarios

Nguyen Huu Anh Tuan

Architecture Civil Engineering Environment

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2021

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Vol. 14, no. 4

105--114

EN

Contemporary floor vibration guidelines limit the discussion of walking-induced vibrations to single-pedestrian loading scenario. Nevertheless, the inclusion of more than one pedestrian in the vibration evaluation would result in a more realistic range of floor responses. In this paper, an attempt was made to experimentally and numerically investigate the combined effect of two persons walking simultaneously on an actual building floor. The floor fundamental frequency and damping ratio were obtained from physical heel drop tests and the footfall response was measured in a series of walking tests. A finite element model was created for prediction of floor responses under different walking scenarios. A probabilistic prediction was also performed where random variations in pacing rates, body weights and arrival times of the pedestrians were considered in a large number of Monte Carlo simulations. It was showed that the response due to a single person with resonant step frequency can be greater than that due to two persons walking at off-resonant pacing rates. However, the resonant response induced by two pedestrians can be 1.29-1.38 times greater than that caused by a pedestrian.

13

Bernoulli Meets PBFT: Modeling BFT Protocols in the Presence of Dynamic Failures

Nischwitz Martin, Esche Marko, Tschorsch Florian

Annals of Computer Science and Information Systems

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2021

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Vol. 25

291--300

EN

The publication of the pivotal state machine replication protocol PBFT laid the foundation for a body of BFT protocols. We introduce a probabilistic model for evaluating BFT protocols in the presence of dynamic link and crash failures. The model is derived from the communication pattern, facilitating an adaptation to other protocols. The state of replicas is captured and used to derive the success probability of the protocol execution. To this end, we examine the influence of link and crash failure rates as well as the number of replicas. A comparison in protocol behavior of PBFT, Zyzzyva and SBFT is performed.

14

Two entropy theory wings as a new trend for the modern means of air transport operational reliability measure

Goncharenko Andriy Viktorovich

Transactions on Aerospace Research

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2020

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Nr 3 (260)

64--74

EN

The paper deals with the uncertainty of the operated system’s possible states hybrid combined optional functions. Traditionally, the probabilities of the system’s possible states are treated as the reliability measures. However, in the framework of the proposed doctrine, the optimality (for example, the maximal probability of the system’s state) is determined based upon a plausible assumption of the intrinsic objectively existing parameters. The two entropy theory wings consider on one hand the subjective preferences functions in subjective analysis, concerning the multi-alternativeness of the operational situation at an individual’s choice problems, and on the other hand the objectively existing characteristics used in theoretical physics. The discussed in the paper entropy paradigm proceeds with the objectively presented phenomena of the state’s probability and the probability’s maximum. The theoretical speculations and mathematical derivations are illustrated with the necessary plotted diagrams.

PL

Artykuł dotyczy niepewności możliwych stanów eksploatowanego systemu hybrydowych połączonych funkcji opcjonalnych. Tradycyjnie jako miary niezawodności traktuje się prawdopodobieństwa możliwych stanów systemu. Jednak w ramach proponowanej doktryny optymalność (na przykład maksymalne prawdopodobieństwo stanu systemu) jest określana na podstawie wiarygodnego założenia o obiektywnie istniejących parametrach wewnętrznych. Dwa kierunki w teorii entropii uwzględniają z jednej strony subiektywne funkcje preferencji w analizie subiektywnej, dotyczące wielowariantowości sytuacji operacyjnej przy indywidualnych problemach wyboru, a z drugiej strony obiektywnie istniejące cechy stosowane w fizyce teoretycznej. Omawiany w artykule paradygmat entropii kontynuuje obiektywnie przedstawione zjawiska prawdopodobieństwa stanu i maksimum prawdopodobieństwa. Spekulacje teoretyczne i wyprowadzenia matematyczne zilustrowano za pomocą niezbędnych wykresów.

15

Szanse na sukces w procesie komercjalizacji

Gierulski Wacław, Kaczmarska Bożena

Przegląd Mechaniczny

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2020

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nr 4

22--29

PL

W pracy poruszono zagadnienie komercjalizacji wynalazków w aspekcie prawdopodobieństwa sukcesu rozumianego jako zysk ze sprzedaży wyprodukowanych towarów. Zaproponowano model procesu komercjalizacji ze wskazaniem punktów decyzyjnych i odniesieniem do skali TRL. Przedstawiono wyniki symulacji procesu komercjalizacji dla pewnych wartości prawdopodobieństwa warunkowego przypisanego punktom decyzyjnym. Jest to autorskie spojrzenie na proces komercjalizacji, jednak nie sprzeczne z innymi występującymi w literaturze przedmiotu.

EN

The paper discusses the issue of commercialization of inventions in terms of the probability of success understood as the profit from the sale of manufactured goods. A model of the commercialization process was proposed with the indication of decision points and reference to the TRL scale. The results of the simulation of the commercialization process are presented for certain values of conditional probability assigned to the decision points. This is the author’s view of the commercialization process, but not contradictory to others presented in the literature.

16

Reliability determination of nanoelectronic devices using semi-Marcov processes

Tomaszewska Justyna, Barański Jan, Zienkiewicz Tomasz, Iwaniuk Marek, Kurzyk Bartłomiej

Journal of KONBiN

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2020

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Vol. 50, iss. 3

277--296

EN

The main purpose of the article is to investigate the reliability process of nanoelectronics devices. Firstly, the research problem is presented based on foreign data source. Then, the analytical method has been chosen – semi-Marcov processes. Next, according to the adopted method and input data, the operating process has been analyzed. Finally, the probabilities of objects being in particular operating states, e.g. in the state of failure-free operation have been determined.

PL

W artykule badany jest proces niezawodności urządzeń nanoelektronicznych. Na początku przedstawiono problem badawczy, w oparciu o zagraniczne źródła danych. Następnie dobrano metodę analityczną – procesy półmarkowowskie. W kolejnej części, bazując na przyjętej metodzie i danych wejściowych, przeanalizowano proces eksploatacji, wyznaczając prawdopodobieństwa przebywania obiektów w poszczególnych stanach eksploatacyjnych, np. w stanie bezawaryjnej pracy.

17

Stochastic multi-depot vehicle routing problem with pickup and delivery: an ILS approach

Rios Brenner H. O., Xavier Eduardo C., Miyazawa Flávio K., Amorim Pedro

Annals of Computer Science and Information Systems

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2020

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Vol. 21

307--315

EN

We present a natural probabilistic variation of the multi-depot vehicle routing problem with pickup and delivery (MDVRPPD). In this paper, we present a variation of this deterministic problem, where each pair of pickup and delivery points are present with some probability, and their realization are only known after the routes are computed. We denote this stochastic version by S-MDVRPPD. One route for each depot must be computed satisfying precedence constraints, where each pickup point must appear before its delivery pair in the route. The objective is to find a solution with minimum expected traveling distance. We present a closed-form expression to compute the expected length of an a priori route under general probabilistic assumptions. To solve the S-MDVRPPD we propose an Iterated Local Search (ILS) that uses the Variable Neighborhood Descent (VND) as local search procedure. The proposed heuristic was compared with a Tabu Search (TS) algorithm based on a previous work. We evaluate the performance of these heuristics on a data set adapted from TSPLIB instances. The results show that the ILS proposed is efficient and effective to solve S-MDVRPPD.

18

Proposed Hypothesis on replacing Non-Deterministic Approach to Abstraction due to the exhibition of faulty speculations

Indukuri Shreya, Konda Anil Kumar Reddy, Sharma Mellacheruvu Janakirama

Annals of Computer Science and Information Systems

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2020

|

Vol. 24

69--72

EN

Non-Determinism is the word that is used to refer to an event or a series of the same that is said to be unpredictable but is assumed to be belonging to a domain of possibilities. From the inception, non-deterministic approaches have played a huge role in statistics, machine design, the definition of Random, and a few other domains to mention. Non-Deterministic processes are defined as the paths that lead to no fixed state but a set of possible states instead. One of the crucial reasons would be delving into the human understanding of processes and the ability to justify happenings around. A behavior that has accumulated throughout the evolution of mankind is to explain boundaries based on what is being perceived. The argument of Human Understanding of processes around can be of huge prominence as they play a vital role in explaining and demystifying a lot of misconceptions. One such aspect that is a resultant of this phenomenon would be a nondeterministic approach. The key focus of this paper will be on emphasizing how humans are limited to perceiving reality, how several misconceptions have accumulated around misstated definitions by the virtue of the same, have a closer look at Randomness, a sheer epitome of the same, and also propose a few potential applications that are affected by the hitherto stated problem.

19

Dynamic Clustering Personalization for Recommending Long Tail Items

Vinícius de Sousa Silva Diogo, Araújo Durão Frederico

Annals of Computer Science and Information Systems

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2020

|

Vol. 21

417--425

EN

Recommendation strategies are used in several contexts in order to bring potential users closer to products with a strong probability of interest. When recomendations focus on niche items, they are called recommendations in the long tail. In these cases, they also look for less popular items and try to find your target custumer, niche market. This paper proposes a long tail recommendation approach that prioritizes relevance, diversity and popularity of recommended items. For that, a hybrid approach based on two techniques are used. The first is clustering with dynamic parameters that adapt from according to the dataset used and the second is a type of Markov chains for to calculate the distance of interest of a user to an item of relevance for this user. The results show that the techniques used have a better relevance indexes at the same time more diverse and less popular recommendations.

20

Developing Defense Strategies from Attack Probability Trees in Software Risk Assessment

Esche Marko, Grasso Toro Federico

Annals of Computer Science and Information Systems

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2020

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Vol. 21

527--536

EN

Since the introduction of the Measuring Instruments Directive 2014/32/EU, prototypes of measuring instruments subject to legal control in the European Union must be accompanied by a risk assessment, when being submitted for conformity assessment. Taximeters, water meters, electricity meters or fuel pumps form the basis for the economic sector usually known as Legal Metrology, where the development towards cheaper allpurpose hardware combined with more sophisticated software is imminent. Therefore, a risk assessment will always have to include software-related issues. Hitherto, publications about software risk assessment methods lack an efficient means to derive and assess suitable countermeasures for risk mitigation. To this end, attack trees are used in related research fields. In this paper, defense probability trees are derived from attack probability trees, well-suited to the requirements of software risk assessment and used to identify optimal sets of countermeasures. The infamous Meltdown vulnerability is used to highlight the experimental application of the method.