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1

Measuring Trustworthiness in Neuro-Symbolic Integration

Agiollo Andrea, Omicini Andrea

Annals of Computer Science and Information Systems

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2023

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Vol. 35

1--10

EN

Neuro-symbolic integration of symbolic and subsymbolic techniques represents a fast-growing AI trend aimed at mitigating the issues of neural networks in terms of decision processes, reasoning, and interpretability. Several state-of-the-art neuro-symbolic approaches aim at improving performance, most of them focusing on proving their effectiveness in terms of raw predictive performance and/or reasoning capabilities. Meanwhile, few efforts have been devoted to increasing model trustworthiness, interpretability, and efficiency - mostly due to the complexity of measuring effectively improvements in terms of trustworthiness and interpretability. This is why here we analyse and discuss the need for ad-hoc trustworthiness metrics for neuro-symbolic techniques. We focus on two popular paradigms mixing subsymbolic computation and symbolic knowledge, namely: (i) symbolic knowledge extraction (SKE), aimed at mapping subsymbolic models into human-interpretable knowledge bases; and (ii) symbolic knowledge injection (SKI), aimed at forcing subsymbolic models to adhere to a given symbolic knowledge. We first emphasise the need for assessing neuro-symbolic approaches from a trustworthiness perspective, highlighting the research challenges linked with this evaluation and the need for ad-hoc trust definitions. Then we summarise recent developments in SKE and SKI metrics focusing specifically on several trustworthiness pillars such as interpretability, efficiency, and robustness of neuro-symbolic methods. Finally, we highlight open research opportunities towards reliable and flexible trustworthiness metrics for neuro-symbolic integration.

2

On precision acoustic wave calculation in a frequency domain

Rymarczyk Tomasz, Sikora Jan

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2022

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T. 12, nr 2

64--68

EN

The accuracy of the calculation of acoustic problems formulated in the frequency domain is presented in this work. The issues of the acoustic point sources modelling were discussed and the influence of frequency as well as the impact of the geometry of the analysed area on the accuracy of calculations were indicated. Speaking about the influence of geometry, we mean not only discretization but also the configuration of the considered area, such as for example point sources localization close to the outer edge.

PL

Dokładności obliczeń zagadnień akustycznych sformułowanych w dziedzinie częstotliwości została przedstawiona w tej pracy. Omówiono problemy modelowania źródeł punktowych oraz wskazano na wpływ częstotliwości a także wpływ geometrii analizowanego obszaru na dokładność obliczeń. Mówiąc o wpływie geometrii mamy na myśli nie tylko dyskretyzacje, ale także konfigurację rozpatrywanego obszaru jak na przykład punktowe źródła energii położone blisko zewnętrznego brzegu.

3

Developing a multiscale in silico cornea for understanding the role of cell mechanics in corneal pathologies

Pant Anup, Paul Elliot, Vahdati Ali

Biocybernetics and Biomedical Engineering

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2020

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Vol. 40, no. 4

1369--1377

EN

Multiscale in silico modeling of the cell-tissue-organ units is an emerging area of research with the potential to improve our understanding of various disease pathogenesis. Using a multiscale modeling approach, we developed a computational model of the human cornea to investigate how the application of macroscale loads may alter the micro-mechanical environment of the cells. We then utilized the multiscale model to study the effect of physiological and non-physiological mechanical loading conditions such as intraocular pressure (IOP) loading, IOP spike, and eye-poking on the corneal cells. On comparing the results obtained under increased IOP and eye-poking loading, we observed large differences in the averaged principal stress magnitudes in the immediate vicinity of the cell through the thickness of the cornea. On the other hand, our model predicted that under physiological IOP loading, the average principal strain magnitudes in the immediate vicinity of the cell remained almost constant irrespective of the cell location in the stroma. To our knowledge, this is the first study that investigates the effect of mechanical loading on the corneal cells through a multiscale modeling framework. Our computational multiscale cornea model provides a platform to perform virtual experiments and test hypotheses to further our understanding of the potential mechanical cause of multiple diseases in the cornea.

4

Enterprise Modeling: From Digital Transformation to Digital Ubiquity

Fill Hans-Georg

Annals of Computer Science and Information Systems

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2020

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Vol. 21

1--4

EN

While digital transformation is still a challenge for many companies when introducting digital technologies in existing processes and business models, digital ubiquity stands for the next step in digitalization. It characterizes the omnipresence of a large range of digital technologies, connectivity, and data as well as entirely digital organizations. This includes for example upcoming technologies such as distributed ledgers, artificial intelligence or augmented reality and according interfaces and data sources as well as decentralized apps and autonomous organizations. The challenge thus becomes to optimally deal with these opportunities and deploy them efficiently in business scenarios. In this paper we will investigate the role of enterprise modeling under this paradigm and how it can contribute to a well-structured, systematic understanding of complex digital phenomena for supporting business and technological decisions.

5

Data Mining-Based Phishing Detection

Bohacik Jan, Skula Ivan, Zabovsky Michal

Annals of Computer Science and Information Systems

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2020

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Vol. 21

27--30

EN

Webpages can be faked easily nowadays and as there are many internet users, it is not hard to find some becoming victims of them. Simultaneously, it is not uncommon these days that more and more activities such as banking and shopping are being moved to the internet, which may lead to huge financial losses. In this paper, a developed Chrome plugin for data mining-based detection of phishing webpages is described. The plugin is written in JavaScript and it uses a C4.5 decision tree model created on the basis of collected data with eight describing attributes. The usability of the model is validated with 10-fold cross-validation and the computation of sensitivity, specificity and overall accuracy. The achieved results of experiments are promising.

6

A Social Robot-based Platform towards Automated Diet Tracking

Alexiadis Anastasios, Triantafyllidis Andreas, Elmas Dimosthenis, Gerovasilis Giorgos, Votis Konstantinos, Tzovaras Dimitrios

Annals of Computer Science and Information Systems

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2020

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Vol. 21

11--14

EN

Diet tracking via self-reports or manual taking of meal photos might be difficult, time-consuming, and discouraging, especially for children, which limits the potential of long-term dietary assessment. We present the design and development of a proof of concept of an automated and unobtrusive system for diet tracking integrating: a) a social robot programmed to automatically capture photos of food and motivate children, b) a deep learning model based on Google Inception V3, applied for the use case of image-based fruit recognition, c) a RESTful microservice architecture deployed to deliver the model outcomes to a platform aiming at childhood obesity prevention. We illustrate the feasibility and virtue of this approach, towards the development of the next-generation computer-assisted systems for automated diet tracking.

7

Modeling morphological learning, typology, and change : What can the neural sequence-to-sequence framework contribute?

Elsner Micha, Sims Andrea D., Erdmann Alexander, Hernandez Antonio, Jaffe Evan, Jin Lifeng, Booker Johnson Martha, Karim Shuan, King David L., Lamberti Nunes Luana, Oh Byung-Doh, Rasmussen Nathan, Shain Cory, Antetomaso Stephanie, Dickinson Kendra V., Diewald Noah, McKenzie Michelle, Stevens-Guille Symon

Journal of Language Modelling

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2019

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Vol. 7, No. 1

53--98

EN

We survey research using neural sequence-to-sequence models as computational models of morphological learning and learnability. We discuss their use in determining the predictability of inflectional exponents, in making predictions about language acquisition and in modeling language change. Finally, we make some proposals for future work in these areas.

8

Measure of adequacy for the supercomputer job management system model

Baranov Anton, Lyakhovets Dmitriy, Savin Gennady, Shabanov Boris, Telegin Pavel

Annals of Computer Science and Information Systems

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2019

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Vol. 18

423--426

EN

In this paper we investigate the problem of modelling modern supercomputer job management systems (JMS). When modelling the JMS, one of the main issues is the adequacy of the model used in experimental studies. The paper attempts to determine the measure of the JMS model adequacy by comparing the characteristics of two job streams, one of which was acquired from a real supercomputer and the other is obtained from the JMS model. We show that the normalized Euclidean distance between vectors of jobs residence times obtained from the job streams of the real system and the JMS model can serve as a measure of the adequacy of the JMS model. The paper also defines the reference value of the measure of adequacy corresponding to the JMS model with virtual nodes.

9

Wybrane aspekty badań symulacyjnych strat w rzeczywistych łączach satelitarnych

Wilk-Jakubowski J. Ł.

Prace Naukowe Akademii im. Jana Długosza w Częstochowie. Technika, Informatyka, Inżynieria Bezpieczeństwa

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2018

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T. 6

135--151

PL

Na konkurencyjność oraz innowacyjność gospodarki światowej wpływa stan zaawansowania technologii TIK. Jednym z rozwiązań podnoszenia jakości świadczonych usług jest dążenie do optymalizacji współczesnych systemów łączności satelitarnej. Z punktu widzenia ich pracy, w celu zapewnienia zadowalającej pracy łącza satelitarnego konieczna jest odpowiednia moc nadajnika. W praktyce moc ta uzależniona jest od wielu czynników, jak chociażby: współrzędne geograficzne miejsca odbioru, ukształtowanie terenu, częstotliwość, lokalizacja anteny (ustawienie anteny), tłumienie sygnału w wolnej przestrzeni, wymagany poziom dostępności łącza. Czynniki te przekładają się na bilans energetyczny łącza satelitarnego, który uzależniony jest ponadto od parametrów technicznych systemu (zwłaszcza: apertury anteny, sprawności anteny oraz całkowitych strat w łączu). W artykule przeanalizowano wpływ całkowitych strat w łączu w zakresie 0,1-0,7 dB na jakość odbioru mikrofalowego sygnału satelitarnego w obszarze Kielc (z uwzględnieniem szumów interferencyjnych), co pozwala przedstawić wpływ tych strat na odbiór sygnału w skrajnie niekorzystnych warunkach.

EN

To ensure satisfactory operation of satellite links in the direction of the satellite-to-earth is essential to get an adequate power of the transmitter. In practice, this power depends on many factors such as: geographical coordinates, terrain, frequency, antenna aperture, antenna efficiency, coupling loss, the signal attenuation in space – in the atmosphere, the required level of availability of bandwidth, etc. Moreover in order to ensure a correct balance, properly conducted link budget requires consideration of extreme weather conditions (precipitation etc.). It is necessary to determine the required transmitter power (or antenna performance) as a function of many factors. The article analyzes the impact of the coupling loss on the receiving satellite signal and presents the results of modeling of these losses in the actual satellite links.

10

Wpływ wybranych parametrów technicznych systemu na odbiór fal radiowych

Wilk-Jakubowski J. Ł.

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2018

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T. 8, nr 3

65--68

PL

Artykuł omawia wpływ wybranych parametrów systemu na odbiór fal radiowych, co ma zastosowanie w optymalizacji systemów łączności. Cel ten realizuje się poprzez dobór parametrów technicznych urządzeń np. współczynnika sprawności anteny odbiorczej. Zwiększenie współczynnika dostępności dla danego systemu wiąże się z minimalizacją wpływu wielu niepożądanych czynników na transmisję fal radiowych (w tym tłumienia podstawowego oraz influencji klimatyczno-atmosferycznej). W rezultacie możliwe staje się zoptymalizowanie istniejących już systemów teletransmisyjnych oraz projektowanie nowych systemów, pozwalających na znaczną poprawę jakości i wiarygodności przekazywanych informacji (zaprezentowane wyniki ograniczą się do częstotliwości z zakresu pasma Ku – powszechnie wykorzystywanego w łączności satelitarnej).

EN

This article presents the influence of selected parameters on the reception of radio waves to optimize communication systems. That goal is achieved by selection of technical parameters of system, eg. antenna efficiency. The result is to minimize the negative effects of free space propagation and induction of climate and Earth's atmosphere in order to increase the G/T figure. In practice, changes in the climatic and atmospheric conditions are significant factors affecting the quality of satellite signal. These results can be used by satellite systems engineers to calculate the link budget analyses of current and future systems through scientifically solid evaluation and assessment. So, these estimates may be useful to improve the design and performance of telematic networks, or to minimize the interruption or lack of communication between the terminal and the satellite in Ku band.

11

Comparison of single-diode models applied to thin film PV module operating under different environmental conditions

Gulkowski S.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2017

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Vol. 21, No 1

43--52

EN

The electrical current-voltage (I-V) characteristic a of photovoltaic (PV) module depends on the environmental conditions under which it operates. The shape of the I-V curve depends on the solar cell technology and changes dynamically in time with irradiance and temperature. A simulation model of the PV module can be used to examine the dynamic behavior of the I-V curve as well as to extract the module parameters from the curves. This paper presents the results of comparison of two different models based on a single-diode equivalent circuit applied to a thin film module. The Matlab/Simulink simulation studies of I-V characteristic curves in the function of irradiance and temperature were carried out. The results were compared with the experimental data of the I-V curves obtained from outdoor measurements. Relative errors of the simulation and experimental results were analyzed.

12

Computer implementation of mass transport in Matlab environment for modeling Epitaxial growth process with moving boundary problem

Gulkowski S.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2015

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Vol. 19, No 1

15--23

EN

Due to the possibility of producing high quality and low cost silicon substrates the Epitaxial Lateral Overgrowth technology may find its application in the photovoltaic industry. However, a lateral growth process depends on many technological parameters such as the temperature of the system, the cooling rate, the solvent or the geometry of the mask. For this reason finding optimized settings for these factors in experimental research is difficult and time consuming. Numerical analysis of the growth process leads to better understanding of the fundamentals of the growth process. For this reason a computational model of epitaxial growth was proposed. This paper focuses on the accuracy of the numerical solution of the mass transport process during epitaxial growth. The method was implemented in the Matlab environment for the moving boundary application. The results of the calculations are presented.

13

Interaction of steel cord – elastomer in radial tyres for passenger vehicles

Krmela J., Benes L., Krmelova V.

Production Engineering Archives

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2014

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Vol. 5, No. 4

10--13

EN

The article focuses on determination of selected material characteristics of samples from different areas of various old passenger tyre casings and on determination of mechanical properties of specific composites with elastomeric matrix and steel reinforcement which are used as steel belts of tyre casing as a sample. These characteristics are used as input data for computational modelling of tyres. It was necessary to carry out various types of experiments to obtain these characteristics. In this article we present the values of the modules of elasticity calculated from the results of DMA tests and static tension tests of samples from old tyre casings and a cohesion test between steel cords and elastomeric matrix. The Mooney-Rivlin parameters, which are necessary input data into computational models of tyres and their parts, were determined from the experimental results. The computational models will be designed to be able to include the effect of aging of the individual tire casing parts. Knowledge of the degradation processes can lead to design and material changes that can increase the resistance of casings against selected forms of degradation processes.

14

Analiza numeryczna CFD przepływu płynu nienewtonowskieao przez mieszalnik statyczny Kenics

Peryt-Stawiarska S.

Przemysł Chemiczny

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2011

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T. 90, nr 9

1661-1663

15

Load balancing in parallel implementation of vascular network modeling

Jurczuk K., Krętowski M., Bézy-Wendling J.

Zeszyty Naukowe Politechniki Białostockiej. Informatyka

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2010

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Z. 6

41-61

EN

In this paper, load balancing mechanisms in a parallel algorithm of vascular network development are investigated. The main attention is focused on the perfusion process (connection of new cells to vascular trees) as it is the most time demanding part of the vascular algorithm. We propose several techniques that aim at balancing load among processors, decreasing their idle time and reducing the communication overhead. The core solution is based on the centralized dynamic load balancing approach. The model behaviors are analyzed and a tradeoff between the different mechanisms is found. The proposed mechanisms are implemented on a computing cluster with the use of the message passing interface (MPI) standard. The experimental results show that the introduced improvements provide a more efficient solution and consequently further accelerate the simulation process.

PL

W artykule rozważane są mechanizmy zrównoważające obciążenie w równoległym algorytmie rozwoju sieci naczyń krwionośnych. Główną uwagę zwrócono na proces perfuzji (podłączanie nowych komórek do drzew krwionośnych) jako, że proces ten jest najbardziej czasochłonnym fragmentem rozpatrywanego algorytmu. Zaproponowane przez autorów rozwiązania mają na celu zrównoważenie obciążenia pomiędzy procesorami, skrócenie ich czasu bezczynności oraz zredukowanie narzutu komunikacyjnego. Jądro rozwiązania jest oparte na scentralizowanym dynamicznym podejściu równoważenia obciążenia. Zachowania modelu zostały przeanalizowane i kompromis pomiędzy różnymi technikami został zaproponowany. Przedstawione mechanizmy zostały zaimplementowane na klastrze obliczeniowym przy wykorzystaniu standardu MPI. Otrzymane rezultaty jednoznacznie pokazuja˛ iż wprowadzone usprawnienia zapewniają bardziej efektywne rozwiązanie co w konsekwencji pozwala na jeszcze większe przyśpieszenie procesu symulacji.

16

Podstawy modelowania CFD mieszalnika

Wójtowicz R.

Czasopismo Techniczne. Mechanika

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2008

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R. 105, z. 2-M

371-384

PL

W pracy przedstawiono podstawy modelowania procesu mieszania cieczy w mieszalniku wibracyjnym, przeprowadzonego z wykorzystaniem metod numerycznej mechaniki płynów (CFD). Omówiono kolejne etapy tworzenia geometrii modelu, generowania siatki numerycznej oraz zastosowania dostępnej w programie metody ruchomej siatki Dynamic Mesh i funkcji UDF do symulacji ruchu mieszadła. Ponadto zaprezentowano przykładowe wyniki przeprowadzonych symulacji w formie wykresów konturowych, map wektorów prędkości oraz rozkładów podstawowych parametrów burzliwości cieczy (szybkości dyssypacji energii [epsilon] i energii kinetycznej burzliwości k) w poszczególnych obszarach mieszalnika.

EN

In the paper are presented the basics of a vibromixer modeling with the use of Computational Fluid Dynamics (CFD) methods. The following stages of modeling: creation of the model geometry, numerical mesh composition and the use of Dynamic Mesh method and UDF function for agitator movement simulation are described. Moreover the results of simulations are presented in the form of contour and vector graphs of velocity and distributions of turbulence parameters (turbulent dissipation rate and [epsilon] and turbulence kinetic energy k) in various vibromixer zones.

17

Noise Reduction of Spiral Ducts

Łapka W., Cempel C.

International Journal of Occupational Safety and Ergonomics

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2007

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Vol. 13, No. 4

419--426

EN

The paper presents noise reduction (NR) of spiral ducts as a result of computational modeling of acoustic wave propagation. Three-dimensional models were created with the finite element method in COMSOL Multiphysics version 3.3. Nine models of spiral ducts with 1–9 spiral leads were considered. Time-harmonic analysis was used to predict NR, which was shown in spectral and interval frequency bands. Spiral duct performance can be seen as a comparison of NR before and after a change from a circular to a spiral duct.