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2020

Fundamental properties of solutions to fractionalorder Maxwell's equations
PublicationIn this paper, fundamental properties of solutions to fractionalorder (FO) Maxwell's equations are analysed. As a starting point, FO Maxwell's equations are introduced in both time and frequency domains. Then, we introduce and prove the fundamental properties of electromagnetic field in FO electromagnetics, i.e. energy conservation, uniqueness of solutions, and reciprocity. Furthermore, the algorithm of the plane wave simulation...

Improved model of isothermal and incompressible fluid flow in pipelines versus the Darcy–Weisbach equation and the issue of friction factor
PublicationIn this article, we consider the modelling of stationary incompressible and isothermal onedimensional fluid flow through a long pipeline. The approximation of the average pressure in the developed model by the arithmetic mean of inlet and outlet pressures leads to the known empirical Darcy–Weisbach equation. Most importantly, we also present another improved approach that is more accurate because the average pressure is estimated...

Interpretation and modeling of emotions in the management of autonomous robots using a control paradigm based on a scheduling variable
PublicationThe paper presents a technical introduction to psychological theories of emotions. It highlights a usable ideaimplemented in a number of recently developed computational systems of emotions, and the hypothesis thatemotion can play the role of a scheduling variable in controlling autonomous robots. In the main part ofthis study, we outline our own computational system of emotion – xEmotion – designed as a key structuralelement in...

Magnetic switching of Kerker scattering in spherical microresonators
PublicationMagnetooptical materials have become a key tool in functional nanophotonics, mainly due to their ability to offer active tuning between two different operational states in subwavelength structures. In the longwavelength limit, such states may be considered as the directional forward and backscattering operations, due to the interplay between magnetic and electric dipolar modes, which act as equivalent Huygens sources. In this...

Neuronowo Sterowane Agenty w Procesie Zespołowego Zaganiania
PublicationPrzedstawiono rozwiązanie problemu zaganiania na drodze uczenia algorytmami ewolucyjnymi. Neuronowe agenty aktywne na podstawie informacji o położeniach pozostałych agentów aktywnych i biernych poprzez odpowiednie poruszanie się skupiają agenty bierne na możliwie małej powierzchni.

Nonreciprocal cavities and the timebandwidth limit: comment
PublicationIn their paper in Optica 6, 104 (2019), Mann et al. claim that linear, timeinvariant nonreciprocal structures cannot overcome the timebandwidth limit and do not exhibit an advantage over their reciprocal counterparts, specifically with regard to their timebandwidth performance. In this Comment, we argue that these conclusions are unfounded. On the basis of both rigorous fullwave simulations and insightful physical justifications,...

OpenSource Coprocessor for Integer Multiple Precision Arithmetic
PublicationThis paper presents an opensource digital circuit of the coprocessor for an integer multipleprecision arithmetic (MPA). The purpose of this coprocessor is to support a central processing unit (CPU) by offloading computations requiring integer precision higher than 32/64 bits. The coprocessor is developed using the very high speed integrated circuit hardware description language (VHDL) as an intellectual property (IP) core. Therefore,...

Signal propagation in electromagnetic media described by fractionalorder models
PublicationIn this paper, signal propagation is analysed in electromagnetic media described by fractionalorder (FO) models (FOMs). Maxwell’s equations with FO constitutive relations are introduced in the time domain. Then, their phasor representation is derived for onedimensional case of the plane wave propagation. With the use of the Fourier transformation, the algorithm for simulation of the nonmonochromatic wave propagation is introduced....
2019

Acceleration of the Discrete Green’s Function Formulation of the FDTD Method Based on Recurrence Schemes
PublicationIn this paper, we investigate an acceleration of the discrete Green's function (DGF) formulation of the FDTD method (DGFFDTD) with the use of recurrence schemes. The DGFFDTD method allows one to compute FDTD solutions as a convolution of the excitation with the DGF kernel. Hence, it does not require to execute a leapfrog timestepping scheme in a whole computational domain for this purpose. Until recently, the DGF generation...

Classification of objects in the LIDAR point clouds using Deep Neural Networks based on the PointNet model
PublicationThis work attempts to meet the challenges associated with the classification of LIDAR point clouds by means of deep learning. In addition to achieving high accuracy, the designed system should allow the classification of point clouds covering an area of several dozen square kilometers within a reasonable time interval. Therefore, it must be characterized by fast processing and efficient use of memory. Thus, the most popular approaches...

Electromagneticbased derivation of fractionalorder circuit theory
PublicationIn this paper, foundations of the fractionalorder circuit theory are revisited. Although many papers have been devoted to fractionalorder modelling of electrical circuits, there are relatively few foundations for such an approach. Therefore, we derive fractionalorder lumpedelement equations for capacitors, inductors and resistors, as well as Kirchhoff’s voltage and current laws using quasistatic approximations of fractionalorder...

Elementy psychologii w kontekście autonomii robotów
PublicationW niniejszym opracowaniu zaprezentowano szerokie spektrum zagadnień związanych z psychologią poznawczą w kontekście antropoidalnej robotyki. W szczególności omówiono sposób przetwarzania informacji u człowieka, od bodźca do reakcji, tak aby przedstawioną wiedzę można było wykorzystać przy projektowaniu robotów autonomicznych. Na początku pracy szczegółowo omówiono procesy poznawcze: percepcję sensoryczną, spostrzeganie,...

Emotion monitoring system for drivers
PublicationThis article describes a new approach to the issue of building a driver monitoring system. Actual systems focus, for example, on tracking eyelid and eyebrow movements that result from fatigue. We propose a different approach based on monitoring the state of emotions. Such a system assumes that by using the emotion model based on our own concept, referred to as the reverse Plutchik’s paraboloid of emotions, the recognition of emotions...

Fractional Order Circuit Elements Derived from Electromagnetism
PublicationIn this paper, derivations of fractionalorder (FO) circuitelement equations from electromagnetism are presented. Whilst many papers are devoted to FO modelling of electrical circuits, there are no strong foundations for such an approach. Therefore, we investigate relations between the FO electromagnetism and the FO circuit theory. Our derivations start from quasistatic (QS) approximations of Maxwell's equations in media with...

Implementation of Addition and Subtraction Operations in Multiple Precision Arithmetic
PublicationIn this paper, we present a digital circuit of arithmetic unit implementing addition and subtraction operations in multipleprecision arithmetic (MPA). This addersubtractor unit is a part of MPA coprocessor supporting and offloading the central processing unit (CPU) in computations requiring precision higher than 32/64 bits. Although addition and subtraction operations of two ndigit numbers require O(n) operations, the efficient...

Implementation of control system and tracking objects in a Quadcopter
PublicationIn this paper, we implement a quadcopter assembly with control and navigation module. The project also includes the design of the control panel for the operator which consists of a set of the microcontroller and the glove equipped with sensors and buttons. The panel has a touch screen which displays current parameters such as vehicle status, including information about orientation and geographical coordinates. The concept of quadcopter...

Intelligent Autonomous Robot Supporting Small Pets in Domestic Environment
PublicationIn this contribution, we present preliminary results of the student project aimed at the development of an intelligent autonomous robot supporting small pets in a domestic environment. The main task of this robot is to protect a freely moving small pets against accidental stepping on them by home residents. For this purpose, we have developed the mobile robot which follows a pet and makes an alarm signal when a human is approaching....

Intelligent Autonomous Vehicles
PublicationAdvanced mobile vehicles and robots have long been one of the main issues in engineering. They have various applications in emergency, lifeguarding and entertainment as well as in various industrial, civil and military systems. Among them, you can distinguish robots that can move in an open environment or operate only in predetermined confined spaces. Open world robots are very demanding because they have...

Intelligent monitoring the vertical dynamics of wheeled inspection vehicles
PublicationThe problem of intelligent monitoring of the vertical dynamics of wheeled inspection vehicles is addressed. With the independent MacPherson suspension system installed, the basic analysis focuses on the evaluation of the parameters of the socalled quarter car model. To identify a physically motivated continuous description, in practice, dedicated integralhorizontal filters are used. The obtained discrete model, which retains...

JamesBot  an intelligent agent playing StarCraft II
PublicationThe most popular method for optimizing a certain strategy based on a reward is Reinforcement Learning (RL). Lately, a big challenge for this technique are computer games such as StarCraft II which is a realtime strategy game, created by Blizzard. The main idea of this game is to fight between agents and control objects on the battlefield in order to defeat the enemy. This work concerns creating an autonomous bot using reinforced...

Modeling of medium flow processes in transportation pipelines  the synthesis of their statespace models and the analysis of the mathematical properties of the models for leak detection purposes
PublicationThe dissertation concerns the issue of modeling the pipeline flow process under incompressible and isothermal conditions, with a target application to the leak detection and isolation systems. First, an introduction to the modelbased process diagnostics is provided, where its basic terminology, tools, and methods are described. In the following chapter, a review of the state of the art in the field of leak detection and isolation...

Odwzorowanie obiektów ograniczonego środowiska na trójwymiarowej mapie cyfrowej z wykorzystaniem robotów mobilnych zaopatrzonych w stereowizję
PublicationProblem podjęty w rozprawie dotyczy trójwymiarowego odwzorowania otoczenia przez roboty mobilne. Wpisuje się on w zagadnienie SLAM  jednoczesnego określania położenia i tworzenia mapy. W pracy skupiono się na wybranej realizacji mapowania opartej na stereowizji (konkretnego zagadnienia SLAM). Duży nacisk położono także na warunki konieczne do zapewnienia prawidłowej stereowizji oraz na sprzętowy układ eksperymentu, który umożliwia...

Recurrence scheme for FDTDcompatible discrete Green's function derived based on properties of Gauss hypergeometric function
PublicationIn this paper, the formulation of onedimensional FDTD (Finitedifference timedomain)compatible discrete Green's function (DGF) is derived based on the Gauss hypergeometric function (GHF). The properties of GHF make it possible to derive the recurrence scheme only in the time domain for the DGF generation. Furthermore, this recurrence scheme is valid for any stable timestep size and can be implemented using standard numerical...

Sieciowy Monitor Obiektu – rozproszony system inteligentnego zarządzania złożonymi obiektami przemysłowymi
PublicationCelem pracy jest opracowanie kompletnego środowiska pozwalającego na budowę autonomicznych systemów diagnostyki, monitorowania, sterowania i zarządzania inteligentnymi budynkami. W ramach przeprowadzonych prac badawczych przedstawiono opracowaną koncepcję Sieciowego Monitora Obiektu (SMO) oraz metody komunikacji pomiędzy urządzeniami pomiarowo diagnostycznosterującymi w oparciu o wspólną szynę danych Diagnostic Service...

Sphere Drive and Control System for Haptic Interaction With Physical, Virtual, and Augmented Reality
PublicationA system for haptic interaction with physical, virtual, and augmented realities, founded on drive and measurement elements (DMEs), is considered. The system consists of eight DME rolls equipped with linear actuators, able to measure their angular velocity, drive the sphere, and adjust downforce (pressing the roll against the sphere). Two modeling issues are addressed. Special effort is put in to compensate for various technical...

System bezpieczeństwa dla współpracującego robota przemysłowego na bazie kamer głębi
PublicationW artykule zarysowano problematykę robotyzacji małych przedsiębiorstw, w szczególności aspekt robotyzacji z uwzględnieniem robotów współpracujących. Szeroko omówiono zagadnienie robotów współpracujących oraz bezpieczeństwa człowieka podczas takiej współpracy. Przedstawiono również najbardziej popularne systemy bezpieczeństwa w odniesieniu do obowiązujących norm. W głównej części artykułu przedstawiono Cooperating Automaton System...

The impact of the temperament model on the behavior of an autonomous driver
PublicationBecause it is generally believed that the personality and temperament of a human driver influence his/her behavior on the road, the article presents a computational model of the temperament of an autonomous agent  a driver. First, a short review of the four ideas of Galen’s temperament in psychology is presented. Temperament traits are grouped into four other sets, one of which is chosen for implementation in the project of integration...

The impact of the temperament model on the behavior of an autonomous driver
PublicationBecause it is generally believed that the personality and temperament of a human driver influence his/her behavior on the road, the article presents a computational model of the temperament of an autonomous agent  a driver. First, a short review of the four ideas of Galen’s temperament in psychology is presented. Temperament traits are grouped into four other sets, one of which is chosen for implementation in the project of integration...
2018

A New Approach to Stability Evaluation of Digital Filters
PublicationIn this paper, a new numerical method of evaluating digital filter stability is presented. This approach is based on novel rootfinding algorithms at the complex plane using the Delaunay triangulation and Cauchy's Argument Principle. The presented algorithm locates unstable zeros of the characteristic equation with their multiplicities. The proposed method is generic and can be applied to a vast range of systems. Verification of...

An Intelligent DecisionMaking System for Autonomous Units Based on the Mind Model
PublicationThis article presents a specific part of current trends in autonomous robotics. It pays special attention to the basic aspects of cognitive architecture. After a brief introduction, we shortly describe the Intelligent System of Decisionmaking developed at the Gdansk University of Technology.

Analytical SteadyState Model of the Pipeline Flow Process
PublicationThe paper addresses the issue of modeling the flow process in transmission pipelines. A base model used for numerical simulation is introduced. Under certain assumptions concerning steady state analysis, the differential equations describing the process are solved analytically for two cases: zero and nonzero inclination angle α. These equations describe a constant flow rate and a corresponding distribution of the pressure along...

Approximate Criteria for the Evaluation of Truly MultiDimensional Optimization Problems
PublicationIn this paper we propose new improved approximate quality criteria useful in assessing the efficiency of evolutionary multiobjective optimization (EMO). In the performed comparative study we take into account the various EMO algorithms of the stateoftheart, in order to objectively assess the EMO performance in highly dimensional spaces. It is well known that useful executive criteria, such as those based on the true Pareto...

Approximate Quality Criteria for Difficult MultiObjective Optimization Problems
PublicationThis paper introduces approximate analytic quality criteria useful in assessing the efficiency of evolutionary multiobjective optimization (EMO) procedures. We present a summary of extensive research into computing. In the performed comparative study we take into account the various approaches of the stateoftheart, in order to objectively assess the EMO performance in highly dimensional spaces; where some executive criteria,...

Constructing autonomous agents using the cognitiveemotional architecture of the mind
PublicationThe article discusses an important issue regarding the humanoid aspects of modern science related to the autonomy of systems and robotization. Particular attention is paid to the basic aspects of cognitive architecture. After a short introduction, the Intelligent Decision Making System, developed at the ETI Faculty of the Gdańsk University of Technology, is described.

Embodying Intelligence in Autonomous and Robotic Systems with the Use of Cognitive Psychology and Motivation Theories
PublicationThe article discusses, on a certain level of abstraction and generalization, a coherent anthropological approach to the issue of controlling autonomous robots or agents. A contemporary idea can be based on appropriate modeling of the human mind using the available psychological knowledge. One of the main reasons for developing such projects is the lack of available and effective topdown approaches resulting from the known research...

Estimation of a Stochastic Burgers' Equation Using an Ensemble Kalman Filter
PublicationIn this work, we consider a difficult problem of state estimation of nonlinear stochastic partial differential equations (SPDE) based on uncertain measurements. The presented solution uses the method of lines (MoL), which allows us to discretize a stochastic partial differential equation in a spatial dimension and represent it as a system of coupled continuoustime ordinary stochastic differential equations (SDE). For such a system...

Gender approaches to evolutionary multiobjective optimization using preselection of criteria
PublicationA novel idea to perform evolutionary computations (ECs) for solving highly dimensional multiobjective optimization (MOO) problems is proposed. Following the general idea of evolution, it is proposed that information about gender is used to distinguish between various groups of objectives and identify the (aggregate) nature of optimality of individuals (solutions). This identification is drawn out of the fitness of individuals...

Identification of Continuous Systems  Practical Issues of Insensitivity to Perturbations
PublicationIn this paper the issue of continuous systems estimation, insensitive to certain perturbations, is discussed. Such an approach has rational advantages, especially when robust schemes are used to assist a target system responsible for industrial diagnostics. This requires that estimated model parameters are generated online, and their values are reliable and to a great extent accurate. Practical hints are suggested to challenge...

Identification of Emotions Based on Human Facial Expressions Using a ColorSpace Approach
PublicationHCI technology improves humancomputer interaction. Such communication can be carried out with the use of emotions that are visible on the human face since birth. In this paper the Emotion system for detecting and recognizing facial expressions, developed in the MSc work, is presented. The system recognizes emotion from webcam video in real time. It is based on color segmentation and morphological operations. The system uses a...

IP Core of Coprocessor for MultiplePrecisionArithmetic Computations
PublicationIn this paper, we present an IP core of coprocessor supporting computations requiring integer multipleprecision arithmetic (MPA). Whilst standard 32/64bit arithmetic is sufficient to solve many computing problems, there are still applications that require higher numerical precision. Hence, the purpose of the developed coprocessor is to support and offload central processing unit (CPU) in such computations. The developed digital...

LowCost Flight Simulator with Possibility of Modeling of Flight Controls Failures
PublicationThe goal of this paper is to present a development of a low cost flight simulator, that allows to simulate flight controls failures. Cessna 172 has been chosen as an example of a general aviation aircraft and the flight model has been implemented in Simulink. The model allows for easy integration of an experimental autopilot, using various strategies. Aerodynamic coefficients have been calculated using software called DATCOM. Such...

Numerical Test for Stability Evaluation of DiscreteTime Systems
PublicationIn this paper, a new numerical test for stability evaluation of discretetime systems is presented. It is based on modern rootfinding techniques at the complex plane employing the Delaunay triangulation and Cauchy's Argument Principle. The method evaluates if a system is stable and returns possible values and multiplicities of unstable zeros of the characteristic equation. For statespace discretetime models, the developed test...

Reduction of Computational Complexity in Simulations of the Flow Process in Transmission Pipelines
PublicationThe paper addresses the problem of computational efficiency of the pipeflow model used in leak detection and identification systems. Analysis of the model brings attention to its specific structure, where all matrices are sparse. With certain rearrangements, the model can be reduced to a set of equations with tridiagonal matrices. Such equations can be solved using the Thomas algorithm. This method provides almost the same values...

River Flow Simulation Based on the HECRAS System
PublicationThis work considers the problem of river floods, and presents a computer solution that can be used to predict such a threat. The basic tool, called Hydrologic Engineering Centers for River Analysis System (HECRAS), and created by the US Army Corps of Engineering, is well developed; and the models created in the system HECRAS are quite realistic. For the purpose of solving practical national flood problems, simplified static and...

Sphere Drive and Control System for Haptic Interaction With Physical, Virtual, and Augmented Reality
PublicationA system for haptic interaction with physical, virtual, and augmented realities, founded on drive and measurement elements (DMEs), is considered. The system consists of eight DME rolls equipped with linear actuators, able to measure their angular velocity, drive the sphere, and adjust downforce (pressing the roll against the sphere). Two modeling issues are addressed. Special effort is put in to compensate for various technical...

The Use of an Autoencoder in the Problem of Shepherding
PublicationThis paper refers to the problem of shepherding clusters of passive agents consisting of a large number of objects by a team of active agents. The problem of shepherding and the difficulties that arise with the increasing number of data describing the location of agents have been described. Several methods for reducing the dimensionality of data are presented. Selected autoencoding method using a Restricted Boltzmann Machine is...

Usuwanie tła w video nagraniach pochodzących z monitorowania basenu pływackiego
PublicationAutomatyczna obróbka obrazu w czasie rzeczywistym jest kluczowa dla wielu rozwiązań monitoringu wykorzystywanych m.in. w celach bezpieczeństwa. Często jednym z ważniejszych etapów obróbki jest oddzielenie tła od obiektów na pierwszym planie, tak aby wykluczyć wszystkie nieistotne informacje z obrazu. Celem niniejszej pracy jest podsumowanie doświadczenia zdobytego podczas śledzenia pływaków oraz pokazanie możliwości skutecznego...
2017

Analysis of economical lighting of highways in the environment of SMOL language
PublicationThe paper puts forward and implements a method of designing and creating a modelling simulation environment for eztensive and complete analysis of economical lighting on highways. From a general design viewpoint, the proposed solution explores the concept of a network description language (SMOL), which has been designed to describe the necessary network functions, mechanisms, and devices; for the purpose of their computer simulation...

Analytical Expression for the TimeDomain Green's Function of a Discrete Plane Wave Propagating in the 3D FDTD Grid
PublicationIn this paper, a closedform expression for the timedomain dyadic Green’s function of a discrete plane wave (DPW) propagating in a 3D finitedifference timedomain (FDTD) grid is derived. In order to verify our findings, the timedomain implementation of the DPWinjection technique is developed with the use of the derived expression for 3D totalfield/scatteredfield (TFSF) FDTD simulations. This implementation requires computations...

Antropoidalny Model Inteligentnego Systemu Decyzyjnego dla Jednostek Autonomicznych
PublicationGłównym celem pracy jest opracowanie modelu procesów psychologicznych  od momentu otrzymania bodźca do momentu podjęcia adekwatnej reakcji  zachodzących w mózgu człowieka (psychologia poznawcza), oraz teorii motywacji (potrzeb, popędów i emocji). Model, zaprezentowany w pracy nazwany Inteligentnym Systemem Decyzyjnym (ISD), może mieć zastosowanie w systemie sterowania jednostką autonomiczną (agentem). W rozprawie rozważa się...