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1

Heat transfer effects on carbon nanotubes along a moving flat plate subjected to uniform heat flux

Ferdows M., Shamshuddin Md., Reza Motahar, Ara Quadir Raushan

International Journal of Applied Mechanics and Engineering

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2022

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Vol. 27, no. 4

66--81

EN

In the present paper, a theoretical analysis is made to investigate fluid flow and heat energy transformation features of single and multi-walled water functionalized carbon nanotubes (CNTs) with uniform heat inconstancy boundary conditions onward a flat plate. The liquid motion and momentum transfer of carbon nanotubes (CNTs) have been analyzed using a homogeneous flow model. Both single-wall CNTs (SWCNTs) and multi-wall CNTs (MWCNTs) used base fluids, namely, water. The thermophysical characteristics of CNTs regarding the solid volume fraction of CNTs are studied by applying empirical correlations. Similarity transformations have been used to the governing partial differential equations turning them into ordinary differential equations. The outcome of similarity transformations which are nonlinear ordinary differential equations subjected to reconstructed boundary conditions, are subsequently solved numerically using bvp4c. The effects of the governing parameters on the dimensionless velocity, temperature, and skin friction are investigated numerically and graphically. An increase in the volume fraction and the velocity ratio parameter increase the flow, the velocity, and the temperature profile. Regardless of any physical parameter, SWCNTs give better heat transfer than MWCNTs.

2

Clustering of data represented by pairwise comparisons

Dvoenko Sergey

Control and Cybernetics

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2022

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Vol. 51, No. 3

343--387

EN

In this paper, experimental data, given in the form of pairwise comparisons, such as distances or similarities, are considered. Clustering algorithms for processing such data are developed based on the well-known k-means procedure. Relations to factor analysis are shown. The problems of improving clustering quality and of finding the proper number of clusters in the case of pairwise comparisons are considered. Illustrative examples are provided.

3

Artificial intelligence applications in anomaly identification detection of big database

Thang Phan Huy, Anh Nguyen Thi Ngoc

Annals of Computer Science and Information Systems

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2021

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Vol. 27

87--92

EN

Data matching is the process of finding, matching, and combining records from many databases or even within one database that belong to the same entities. All parts of the data matching process have been improved during the previous decade as a result of research in various disciplines such as applied statistics, data mining, machine learning, database administration, and digital libraries.Indeed, with the significant advance in artificial intelligence over the past decade, all aspects of the data identification process, especially on how to improve the accuracy of data matching. Firstly, this paper presents the process of comparing data, detailing the steps to perform pre-processing data, comparing the data fields of each record, classification, and quality assessment. Secondly, the paper introduces a method to expand the problem of identifying duplicate objects with big data. Third, the paper also provides specific aspects of unstructured data matching times. Moreover, the methodology of solving big data matching problems by machine learning is proposed. Finally, the proposed method is applied to the problem of database cleanup and identification of identifier abnormalities at the national credit centre CIC with correct results from 96\% to 98\%. The achieved results are not only theoretical but also practical in business operations at CIC.

4

Ma Biao, Yan Shufa, Wang Xu, Chen Jianhua, Zheng Changsong

Eksploatacja i Niezawodność

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2020

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Vol. 22, no. 3

520--529

EN

An accurate determination of the system failure threshold is an essential requirement in achieving an appropriate system residual life prediction and a reasonable planned maintenance strategy optimization afterward for degradation systems. This paper proposes a failure threshold determination method based on quantitative measurement of the similarity between the operating system and the historical systems. The similarity is formulated by a weighted average function and then calculated by a convex quadratic formulation to minimizing the variance between the operating system and the historical systems. With an accurate determination of the system failure threshold in real-time, a better prediction of the residual life for the operating system is achieved. Finally, a real case study for several power-shift steering transmission systems monitored using oil spectral analysis is adopted to illustrate and numerically compare the improved performance of the proposed method.

PL

W przypadku systemów podlegających degradacji, dokładne określenie progu awarii systemu stanowi niezbędny warunek dokonania trafnej prognozy jego trwałości resztkowej oraz późniejszej optymalizacji strategii konserwacji rutynowych. W artykule zaproponowano metodę wyznaczania progu awarii opartą na ilościowym pomiarze podobieństwa między systemem użytkowanym obecnie a systemami użytkowanymi uprzednio. Podobieństwo formułuje się na podstawie funkcji średniej ważonej, a następnie oblicza na podstawie wypukłej formy kwadratowej w celu zminimalizowania wariancji między obecnie użytkowanym systemem a uprzednimi systemami. Dzięki dokładnemu określeniu progu awarii systemu w czasie rzeczywistym uzyskuje się lepszą prognostykę trwałości resztkowej obecnie użytkowanego systemu. W końcowej części pracy, w celu zilustrowania i numerycznego porównania ulepszonej wydajności proponowanej metody, zaprezentowano studium przypadku obejmujące kilka układów przeniesienia napędu monitorowanych przy użyciu analizy spektralnej oleju.

5

Arbelos theory in electrical engineering

Różański Michał, Samulewicz Alicja, Szczygieł Marcin, Wituła Roman, Wyszkowska Joanna

Przegląd Elektrotechniczny

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2019

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R. 95, nr 3

83--86

EN

An arbelos is a plane figure bounded by three semicircles that are pairwise tangent and have diameters lying on the same line. Its name comes from Greek and means Shoemaker's knife. Arbelos shape have the same shape like lines of magnetic field distribution - in ideal form - for two parallel wires. The paper presents the discussion on the analogue of arbelos and their theoretical contributions in electrical engineering.

PL

Arbelos jest częścią płaszczyzny ograniczoną trzema półokręgami, które są parami styczne i mają średnice leżące na tej samej linii. Jego nazwa nazwa wywodzi się z greckiego i oznacza nóż szewski. Kształt arbelos jest podobny do rozkładu linii pola magnetycznego - w idealnej formie - dla dwóch równoległych przewodów. Artykuł przedstawia dyskusję na temat analogii arbelos i zastosowania tej teorii w elektrotechnice.

6

Modelowanie i optymalizacja procedur detekcji zagrożeń epidemiologicznych

Ameljańczyk Andrzej

Inżynieria Bezpieczeństwa Obiektów Antropogenicznych

|

2019

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Nr 1-2

17--27

PL

W pracy przedstawiono ogólny model procedury rozpoznawania zagrożeń epidemiologicznych oparty na wielokryterialnej ocenie podobieństwa zagrożeń do wzorców zawartych w repozytorium. Zdefiniowano ogólną przestrzeń detekcji podobieństwa, w której sformułowano zadanie optymalizacji rozpoznawania wzorców. Przedstawiono przykład algorytmu wspomagania procesu wyznaczania wstępnego rozpoznania oparty na stwierdzonych objawach zagrożenia i występujących czynnikach ryzyka. Przedstawiony algorytm pozwala wyznaczać zbiór zagrożeń od których nie ma bardziej prawdopodobnych oraz jego ranking.

7

Methods of determination thermal conductivity in quasi industrial condition

Urbanek P.

Przegląd Elektrotechniczny

|

2018

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R. 94, nr 4

95--98

EN

In the paper the classic Angstrom method of determining the value of conduction heat transfer has been successfully tested. The usefulness of the Angstrom method was investigated in terms of temperature measurement of metal samples deviating from the general assumptions of the method. A Hamming’s neural network was proposed to simulate the similarity of the sample metal to previously known metals.

PL

W pracy sprawdzono działanie klasycznej metody Angstroma do wyznaczania wartości przewodności cieplnej właściwej. Sprawdzono przydatność tejże metody w warunkach cieplnych odbiegających od założeń metody. Wykorzystano sztuczną sieć neuronową Hamminga do określania stopnia podobieństwa materiału próbki testowej do znanych, typowych stali stosowanych w praktyce przemysłowej.

8

Dialogue in Hierarchical Learning of Concept using Prototypes and Counterexamples

Dutta S., Wasilewski P.

Fundamenta Informaticae

|

2018

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Vol. 162, nr 1

17--36

EN

This paper is an attempt to introduce a notion of dialogue among different agents, e.g. a user or situation descriptor and an information provider or machine, to better understand a user’s need of information. When a user describes a concept through some keywords first the system needs to choose the relevant attributes for initiating the search. Regarding this, a series of dialogues may help the system to better understand the user’s language of expresssion. After fixing the relevant attributes, the system needs to look at its repertoire of positive and negative cases of different concepts characterized with respect to this set of attributes. Then through a step-by-step process of matching and comparing similarity of user’s described situation with those positive and negative cases of a concept, incorporating several layers of dialogue, the system may provide information closer to the user’s need. The target of this paper is to develop a theoretical model, incorporating the above features, for characterizing one’s concern of concept based on dialogue and similarity based reasoning.

9

Prioritizing software capabilities and focal points of MS Access and Excel in perspective of data management

Dakhil Fattah Ali, Ali Weffa Muhammed, Reda Ali Atshan Abdul

Applied Computer Science

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2018

|

Vol. 14, no 3

15--30

EN

Microsoft Corporation products have overwhelmed almost all organiza-tions around the world even beside other operating systems like UNIX, Ubuntu and others. MS Office software products in particular, have being used widely in big portion of our work and business. In specific, MS Access and Excel are very famous and so usable software in between other Microsoft office products. Many similarities are shared between Access and Excel, meanwhile, many key differences are worth to point them out, too. Mainly, this research spotlights on primarily motivated topic of how they can manage data as they have been designed for. The mission of this research is to show how to employee MS Access and Excel in the right way in business work after indicating strength and weaknesses of both of them. Thus, we need to fulfill the right and suitable enough choice between Access and Excel that meets our business work requirements. A detailed list of significant features and key points are discussed and compered of both software leads to conducted proper software use.

10

O podobieństwach i różnicach dwóch najmłodszych cementowni w Opolu

Rawska-Skotniczny A., Molak E.

Przegląd Budowlany

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2017

|

R. 88, nr 3

28--33

PL

Do czasów współczesnych w Opolu przetrwało jedynie kilka cementowni. Tylko jedna z nich wykorzystywana jest jako fabryka cementu. Los dwóch najmłodszych cementowni, wybudowanych w niewielkiej odległości od siebie, po II Wojnie Światowej potoczył się podobnie. Niekiedy w literaturze i w źródłach określa się je jako „bliźniacze”, wysnuto ponadto przypuszczenie o wykorzystaniu do ich budowy tego samego projektu konstrukcyjnego. Przypuszczenie to nie jest prawdziwe, ponieważ cementownie różnią się znacząco pod względem zarówno projektu, jak i materiałów użytych do ich budowy. Autorzy niniejszego artykułu porównują strukturę obu fabryk oraz istniejące pomiędzy nimi różnice.

EN

To modern times it has been survived only a few cement plants in Opole. Only one of them still acts as a cement factory. The two youngest cement plants, built in a small distance, met similar happens after World War II. They are sometimes referred to as „twin” in the literature and sources and is put thesis on the use of the same construction project to build them. This thesis is not true, because they differ significantly in both, design and materials used to construction. The authors compare of the structure and identity of the two factories in the article.

11

Variations on the arbelos

Różański M., Samulewicz A., Szweda M., Wituła R.

Journal of Applied Mathematics and Computational Mechanics

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2017

|

Vol. 16, nr 2

123--133

EN

We recall the ancient notion of arbelos and introduce a number of concepts generalizing it. We follow the ideas presented by J. Sondow in his article on parbelos, the parabolic analogue of the classic arbelos. Our concepts concern the curves constructed of arcs which resemble each other and surfaces obtained in a similar way. We pay special attention to ellarbelos, the curves built of semi-ellipses, because of their possible application in engineering, e.g. in determining the static moments of arc rod constructions or in problems of structural stability and durability of constructions.

12

Analysis of series of measurements from job-centric monitoring by statistical functions

Hilbrich M., Frank M.

Computer Science

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2017

|

Vol. 18 (1)

3--19

EN

The rising number of executed programs (jobs) enabled by the growing amount of available resources from Clouds, Grids, and HPC (for example) has resulted in an enormous number of jobs. Nowadays, most of the executed jobs are mainly unobserved, so unusual behavior, non-optimal resource usage, and silent faults are not systematically searched and analyzed. Job-centric monitoring enables permanent job observation and, thus, enables the analysis of monitoring data. In this paper, we show how statistic functions can be used to analyze job-centric monitoring data and how the methods compare to more-complex analysis methods. Additionally, we present the usefulness of job-centric monitoring based on practical experiences.

13

Impact of Clustering Parameters on the Efficiency of the Knowledge Mining Process in Rule-based Knowledge Bases

Nowak-Brzezińska A., Rybotycki T.

Schedae Informaticae

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2016

|

Vol. 25

85--101

EN

In this work the subject of the application of clustering as a knowledge extraction method from real-world data is discussed. The authors analyze an influence of different clustering parameters on the quality of the created structure of rules clusters and the efficiency of the knowledge mining process for rules / rules clusters. The goal of the experiments was to measure the impact of clustering parameters on the efficiency of the knowledge mining process in rulebased knowledge bases denoted by the size of the created clusters or the size of the representatives. Some parameters guarantee to produce shorter/longer representatives of the created rules clusters as well as smaller/greater clusters sizes.

14

Experimental verification of the scaling laws for CFB boilers of different designs

Mirek P., Klajny M.

Chemical and Process Engineering

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2016

|

Vol. 37, nr 2

281--291

EN

In the paper flow dynamic similarity criteria have been presented to reflect the macroscopic flow pattern in the combustion chamber of large-scale circulating fluidised bed boilers. The proposed scaling rules have been verified on two cold models of CFB boilers operating in Tauron Wytwarzanie S.A. - El. Lagisza division (scale factor 1/20) and Fortum Power and Heat Poland Sp. z o. o. Czestochowa division (scale factor 1/10) – working with the power of 966 MW th and 120 MW th, respectively. As follows from the results of measurements, regardless of CFB boiler’s geometry the use of a defined set of criterial numbers allows to obtain satisfactory agreement between the suspension density distributions registered in the CFB boilers and scaling models.

15

Układy kierowania mobilnych modeli pojazdów wykorzystywanych do badań dynamiki ruchu pojazdów

Parczewski K., Romaniszyn K. M.

Logistyka

|

2015

|

nr 4

789--800, CD1

PL

W publikacji przedstawiono problemy, na jakie napotyka się przy badaniach dynamiki ruchu dużych samochodów ciężarowych samochodów specjalnych z wykorzystaniem modeli fizycznych wykonanych w pomniejszonej skali. Przedstawiono wymagania dotyczące budowy mobilnych, zdalnie sterowanych modeli samochodów, których cechy mogą w pewnym przybliżeniu odwzorowywać parametry ruchu pojazdów rzeczywistych. Założono, że budowane mobilne modele powinny spełniać wybrane kryteria podobieństwa w stosunku do pojazdu rzeczywistego. W publikacji opisano problemy występujące przy budowie takich modeli a szczególnie ich układu kierowania. Konstrukcja modelu ma z założenia odwzorowywać stateczność ruchu zadanego pojazdu rzeczywistego przy zachowaniu wybranych podobieństw między modelem i samochodem rzeczywistym. Samochód ten zbudowano w skali około 1:5 w stosunku do wymiarów samochodu rzeczywistego. Napęd modelu stanowił dwusuwowy silnik spalinowy, a układ napędowy umożliwiał napęd 4x2 lub 4x4. Układ sterowania modelem samochodu pozwalał na odwzorowywanie badań stateczności zgodnie z wybranymi normami ISO.

EN

The publication presents problems they have encountered in studies of dynamics of large trucks and special vehicles using physical models made in a reduced scale. The requirements for the construction of mobile, remote-controlled car models, the characteristics of which may in some approximation reproduce full dimensional vehicle movement parameters. It was assumed that build mobile models should meet the selected criteria of similarity in relation to the real vehicle. The publication describes the problems of the construction of such models and especially their steering system. The aim in building the vehicle model was to approximate the stability of the movement of a given real vehicle while keeping the same given similarities between the model and the real vehicle. It is a 1/5 scale model of the real vehicle and is powered by a 2-stroke combustion engine with an optional 2x4 or 4x4 wheel drive. The model’s steering system allowed the authors to run stability tests in accordance with the chosen ISO standards.

16

Multiple-instance learning with pairwise instance similarity

Yuan L., Liu J., Tang X.

International Journal of Applied Mathematics and Computer Science

|

2014

|

Vol. 24, no. 3

567--577

EN

Multiple-Instance Learning (MIL) has attracted much attention of the machine learning community in recent years and many real-world applications have been successfully formulated as MIL problems. Over the past few years, several Instance Selection-based MIL (ISMIL) algorithms have been presented by using the concept of the embedding space. Although they delivered very promising performance, they often require long computation times for instance selection, leading to a low efficiency of the whole learning process. In this paper, we propose a simple and efficient ISMIL algorithm based on the similarity of pairwise instances within a bag. The basic idea is selecting from every training bag a pair of the most similar instances as instance prototypes and then mapping training bags into the embedding space that is constructed from all the instance prototypes. Thus, the MIL problem can be solved with the standard supervised learning techniques, such as support vector machines. Experiments show that the proposed algorithm is more efficient than its competitors and highly comparable with them in terms of classification accuracy. Moreover, the testing of noise sensitivity demonstrates that our MIL algorithm is very robust to labeling noise.

17

Scenariusze użycia systemu MAS4PSi w diagnostyce medycznej

Górczyńska-Kosiorz S., Małysiak-Mrozek B., Mrozek D.

Studia Informatica

|

2013

|

Vol. 34, nr 2A

337--352

PL

System MAS4PSi (Multi Agent System For Protein Similarity searching) pozwala na szybkie, skalowalne i niezawodne poszukiwanie podobieństwa strukturalnego białek. Poszukiwanie podobieństwa strukturalnego białek jest kluczowe w prowadzeniu badań nad różnymi procesami biologicznymi i innymi obszarami, które mają swoją podstawę w tych procesach biologicznych. Celem niniejszego artykułu jest przybliżenie i określenie możliwych scenariuszy wykorzystania zbudowanego systemu MAS4PSi w powszechnie rozumianej diagnostyce medycznej zarówno na etapie opracowywania eksperymentów pomocnych we wprowadzeniu nowych badań, jak i na etapie typowo diagnostycznym.

EN

MAS4PSi (Multi-Agent System For Protein Similarity searching) is a system that allows fast, scalable and reliable protein structure similarity searching. Protein structure similarity searching is crucial in conducting research on a variety of biological processes, and other areas that have their basis in these biological processes. The purpose of this article is to define and present possible scenarios of using the MAS4PSi system in a broadly understood medical diagnostics, both in the design of experiments supporting new research, as well as the typical diagnostic stage.

18

Evaluating semantic similarity with a new method of path analysis in RDF using genetic algorithms

Strobin Ł, Niewiadomski A.

Journal of Applied Computer Science

|

2013

|

Vol. 21, nr 2

137--152

EN

This paper presents a novel method of evaluating semantic similarity by means of path analysis in RDF databases. Similarity is calculated by assignining each property (predicate in RDF terms) a weight, which is found using a genetic optimization algorithm. Presented method exhibits an advatage over existing methods, because of its ﬂexibility and the fact that no prior knowledge of a particular database is necessary. This paper also presents an exemplary application of the method - recommendation engine. Proposed method is applied to a well known problem - music recommendation based on DBPedia. Results obtained in the experiment positively verify its advanntages and usefulness.

19

Badanie dynamiki ruchu pojazdu z wykorzystaniem modeli wykonanych w skali

Parczewski K., Wnęk H.

Combustion Engines

|

2013

|

R. 52, nr 3

893--902

PL

W pracy przedstawiono próbę wykorzystania modeli fizycznych pojazdów w skali do analizy dynamiki ruchu rzeczywistych pojazdów. Parametry geometryczne modelu oraz kinematykę i dynamikę ruchu określono wykorzystując teorię podobieństwa i analizę wymiarową. Omówiono problemy związane z konstruowaniem i sterowaniem modeli. Zagadnienia dotyczące stateczności ruchu pojazdu wiążą się z jego parametrami charakterystycznymi takimi jak: rozkład mas na poszczególne osie, wysokość środka ciężkości, momenty bezwładności zarówno całego pojazdu jak i masy resorowanej oraz sztywność i tłumienie drgań nadwozia a także położenie osi przechyłu i parametry charakterystyczne opon. Osobny problem stanowi sterowanie modelu, zwłoka czasowa i powtarzalność wykonywanych manewrów. Pomimo problemów konstrukcyjnych wyniki badań są bardzo obiecujące i pozwalają na przeniesienie wyników pomiarów z mobilnego modelu na pojazd rzeczywisty. Co oznacza, że w przypadku pojazdów, produkowanych jednostkowo, bądź pojazdów, których badań nie da się przeprowadzić, można je zastąpić badaniami i pomiarami wykonanymi na modelu w skali.

EN

The paper presents an attempt to use physical models of vehicles on a scale to analyze the dynamics of the real motion of vehicles. Geometric parameters of the model and the kinematics and dynamics of motion defined using the theory of similarity and dimensional analysis. The problems associated with the construction and control models was presented. Considerations for stability of the vehicle motion connected with its characteristic parameters such as weight distribution on each axis, the height of the center of mass, moments of inertia of both the vehicle and the sprung mass and the stiffness and damping of the body as well as the position of the roll axis and the characteristic parameters of the tire. A separate problem is the control of model, time delay and repetition performed maneuvers. Despite the structural design results are very promising and allow for the transfer of the results of tests of the mobile model on a real vehicle. This means that in the case of vehicles manufactured individually, or vehicle, where tests can not be done, it may be replaced by tests and measurements made on the scale model.

20

Multicriteria similarity models for medical diagnostic support algorithms

Ameljańczyk A.

Bio-Algorithms and Med-Systems

|

2013

|

Vol. 9, no. 1

1--7

EN

The paper presents a general procedure model for the identification of diagnostic medical patterns based on multicriteria assessment of similarity. A general similarity detection area was defined, in which a pattern recognition optimization problem was formulated. An exemplary algorithm supporting the process of determining the initial medical diagnosis based on the identified disease symptoms and risk factors is presented. The presented algorithm allows for determining a set of diseases from which there is none more probable, and their ranking.