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Profitable areas in large-scale FTTH network optimization
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Estimation of structural stiffness with the use of Particle Swarm Optimization
PublicationThe paper presents the theoretical background and four applications examples of the new method for the estimation of support stiffness coefficients of complex structures modelled discretely (e.g. with the use of the Finite Element Model (FEM) method based on the modified Particle Swarm Optimization (PSO) algorithm. In real-life cases, exact values of the supports’ stiffness coefficients may change for various reasons...
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The protein folding problem: global optimization of force fields
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CLASSIFICATION OF RESTRAINTS IN THE OPTIMIZATION PROBLEM OF A COLD-FORMED PROFILE
PublicationThis work describes the restraints in the optimization problem. This is an important and complicated issue because it requires taking into account a vast range of information related to the design and production. In order to describe the relations of a specific optimization problem, it is essential to adopt appropriate criteria and to collect information on all kinds of restraints, i.e. boundary conditions. The following paper...
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Size Reduction of Microwave Couplers by EM-Driven Optimization
PublicationThis work addresses simulation-driven design optimization of compact microwave couplers that explicitly aims at circuit footprint area reduction. The penalty function approach allows us to minimize the area of the circuit while ensuring a proper power division between the output ports and providing a sufficient bandwidth with respect to return loss and isolation around the operating frequency. Computational cost of the optimization...
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Multi-objective optimization of expensive electromagnetic simulation models
PublicationVast majority of practical engineering design problems require simultaneous handling of several criteria. For the sake of simplicity and through a priori preference articulation one can turn many design tasks into single-objective problems that can be handled using conventional numerical optimization routines. However, in some situations, acquiring comprehensive knowledge about the system at hand, in particular, about possible...
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A self-optimization mechanism for generalized adaptive notch smoother
PublicationTracking of nonstationary narrowband signals is often accomplished using algorithms called adaptive notch filters (ANFs). Generalized adaptive notch smoothers (GANSs) extend the concepts of adaptive notch filtering in two directions. Firstly, they are designed to estimate coefficients of nonstationary quasi-periodic systems, rather than signals. Secondly, they employ noncausal processing, which greatly improves their accuracy and...
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Applications of semi-definite optimization in quantum information protocols
PublicationThis work is concerned with the issue of applications of the semi-definite programming (SDP) in the field of quantum information sci- ence. Our results of the analysis of certain quantum information protocols using this optimization technique are presented, and an implementation of a relevant numerical tool is introduced. The key method used is NPA discovered by Navascues et al. [Phys. Rev. Lett. 98, 010401 (2007)]. In chapter...
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A Concept of Modeling and Optimization of Applications in Large Scale Systems
PublicationThe chapter presents the idea that includes modeling and subsequent optimization of application execution on large scale parallel and distributed systems. The model considers performance, reliability and power consumption. It should allow easy modeling of various classes of applications while reflecting key parameters of both the applications and two classes of target systems: clusters and volunteer based systems. The chapter presents...
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Some Optimization Methods for Simulations in Volunteer and Grid Systems
PublicationIn this chapter, some optimization methods have been presented for improving performance of simulations in the volunteer and grid computing system called Comcute. Some issues related to the cloud computing can be solved by presented approaches as well as the Comcute platform can be used to simulate execution of expensive and energy consuming long-term tasks in the cloud environment. In particular, evolutionary algorithms as well...
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Small Antenna Design Using Surrogate-Based Optimization
PublicationIn this work, design of small antennas using efficient numerical optimization is investigated. We exploit variable-fidelity electromagnetic (EM) simulations and the adaptively adjusted design specifications (AADS) technique. Combination of these methods allows us to simultaneously adjust multiple geometry parameters of the antenna structure of interest in a computationally feasible manner, leading to substantial reduction of the...
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Ships Shore Service Optimization Using the Queueing Theory
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Parameters optimization in medicine supporting image recognition algorithms
PublicationIn this paper, a procedure of automatic set up of image recognition algorithms' parameters is proposed, for the purpose of reducing the time needed for algorithms' development. The procedure is presented on two medicine supporting algorithms, performing bleeding detection in endoscopic images. Since the algorithms contain multiple parameters which must be specified, empirical testing is usually required to optimise the algorithm's...
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Dimensionless Analysis of Stirling Engine using of Optimization Methods
PublicationW pracy zaprezetowano wyniki analizy wpływu parametrów konstrukcyjnych silnika Stirlinga na jego wskaźniki jakości.Analizę przeprowadzono na modelu bezwymiarowym wykorzystując metody optymalizacji parametrycznej.
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Optimization of microstructure and properties of acceptor-doped barium cerate
PublicationThe presented research concerns acceptor doped barium cerate and the attempts of improvement of its production method that would allow obtaining the solid electrolyte characterized by the particular properties. The authors suggest combining two production methods, molten salt synthesis and self-combustion, in order to achieve the compound material that has some of the advantages of both of the initial methods. An impact of nickel...
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Optimal and safe control planning with the use of discrete optimization
PublicationW opracowaniu zaproponowano metodę projektowania optymalnych i tolerujących uszkodzenia systemów sterowania opartych na wykorzystaniu algorytmów optymalizacji dyskretnej. Publikacja przedstawia potencjalne wady i zalety metody. Główna idea proponowanego algorytmu sprowadza się do wykorzystania struktury grafu przepływowego w celu stworzenia reprezentacji dynamiki własnej danego procesu. Poszukiwana trajektoria optymalna, jeśli...
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Downside Risk Approach for Multi-Objective Portfolio Optimization
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Selected Multiple Criteria Supply Chain Optimization Problems
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Multi-Objective Portfolio Optimization by Mixed Integer Programming
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Multi-Criteria Optimization for Fleet Size with Environmental Aspects
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A Bi-Objective Portfolio Optimization with Conditional Value-at-Risk
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MULTI-OBJECTIVE OPTIMIZATION PROBLEM IN THE OptD-MULTI METHOD
PublicationNew measurement technologies, e.g. Light Detection And Ranging (LiDAR), generate very large datasets. In many cases, it is reasonable to reduce the number of measuring points, but in such a way that the datasets after reduction satisfy specific optimization criteria. For this purpose the Optimum Dataset (OptD) method proposed in [1] and [2] can be applied. The OptD method with the use of several optimization criteria is called...
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Optimization of Bread Production Using Neuro-Fuzzy Modelling
PublicationAutomation of food production is an actively researched domain. One of the areas, where automation is still not progressing significantly is bread making. The process still relies on expert knowledge regarding how to react to procedure changes depending on environmental conditions, quality of the ingredients, etc. In this paper, we propose an ANFIS-based model for changing the mixer speed during the kneading process. Although the...
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The optimization of CuxO microwires synthesis for improvement in photoelectrochemical performance
PublicationOne of the most important challenges in the fabrication of CuxO microstructures via the electrochemical method is formation of long, regular and well-packed microwires with good adhesion on the Cu substrate and to achieve better photoelectrochemical properties, which can be potentially applied in solar-driven water splitting and CO2 conversion to light hydrocarbons. In this paper, Cu2O photoelectrode has been fabricated by direct...
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Particle swarm optimization–artificial neural network modeling and optimization of leachable zinc from flour samples by miniaturized homogenous liquid–liquid microextraction
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Optimization of the femtosecond laser impulse for excitation and the spin-orbit-mediated dissociation in the NaRb molecule
Open Research DataHigh accuracy ab initio potential energy curves (1tSigma+, 2sSigma+, 1tPi), electronic transition dipole moment function (1tSigma+ - 1tPi), and spin-orbit coupling (2sSigma+ - 1tPi) have been calculated for the NaRb molecule. The time-dependent excitation and dissociation processes in the polar alkali diatomic NaRb molecule and the quantum properties...
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Optimization of 1,2-Diaminopropane Preparation by the Ammonolysis of Waste 1,2-Dichloropropane
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Influence of the counterweight model on optimization of balancing of four-bar mechanism
PublicationPraca opisuje rozważania na temat wyrównoważania płaskiego czworoboku przegubowego. Do wyrównoważenia wykorzystano metodę alokacji przeciwmas. Zadanie to wymagało połączenia procedur analizy dynamiki układów wielomasowych z procedurą optymalizacji. W pracy umieszczono opis metody dynamiki układów wielomasowych. W procesie optymalizacji skorzystano z metody sympleksów. Opisano model analizowanego układu składający się z dwóch sekcji...
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Performance analysis and optimization of the Radio Link Control layer in UMTS.
PublicationRLC (Radio Link Control) jest jedną z podwarstw warstwy 2 stosu radiowego systemu UMTS. RLC wspiera trzy podstawowe tryby działania: przezroczysty (Transparent Mode, TM), bezpotwierdzeniowy (Unacknowledged Mode, UM) oraz potwierdzeniowy (Acknowledged Mode, AM). Wydajność RLC AM jest mocno uzależniona od konfiguracji RLC oraz jej zdolności do dynamicznej rekonfiguracji, odzwierciedlającej zmiany w przesyłanym ruchu oraz w jakości...
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AUTOMATIC OPTIMIZATION OF ADAPTIVE NOTCH FILTER’S FREQUEN CY TRACKING
PublicationEstimation of instantaneous frequency of narrowband com- plex sinusoids is often performed using lightweight algo- rithms called adaptive notch filters. However, to reach high performance, these algorithms require careful tuning. The paper proposes a novel self-tuning layer for a recently intr o- ducedadaptive notch filtering algorithm. Analysis shows th at, under Gaussian random-walk type assumptions, the resultin g solution converges...
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Spectral measurement of birefringence using particle swarm optimization analysis
PublicationThe measurement of birefringence is useful for the examination of both technical and biological objects. One of the main problems is that the polarization state of light in birefringent media changes periodically. Without the knowledge of the period number, the birefringence of a given medium cannot be determined reliably. We propose to analyse the spectrum of light in order to determine the birefringence. We use a Particle Swarm...
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Gradient-based optimization of filters using FD-TD software
PublicationW artykule opisane jest nowe podejście do zagadnienia optymalizacji filtrów mikrofalowych pasmowo-przepustowych. Optymalizacja prowadzona jest z wykorzystaniem metody gradientowej poszukiwania minimum wartości funkcji celu oraz przy założeniu pełnofalowej symulacji obwodów metodą różnic skończonych w dziedzinie czasu. W artykule pokazane jest, że stosując zaawansowane techniki cyfrowego przetwarzania sygnałów możliwa jest optymalizacja...
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Noise Analysis and Optimization of Continuous-Time OTA-C Filters
PublicationW pracy przedstawiono efektywną procedurę wyznaczania szumów w filtrach OTA C czasu ciagłego. Procedura wyprowadzona jest w oparciu o ogólny model filtru OTA C oraz jego opis macierzowy. Podano jawne formuły pozwalające okreslić odniesione do wejścia widmo szumów dowolnego filtru rozważanej klasy. Otrzymane wyniki teoretyczne zostały zweryfikowane poprzez porównanie z wynikami otrzymywanymi za pomocą symulatora SPICE dla wybranych...
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Analysis and Optimization of Noise in Continuous-Time OTA-C Filters
PublicationW pracy przedstawiono ogólną procedurę analizy szumów w filtrach klasy OTA-C czasu ciągłego. Procedura umożliwia analizę filtrów o dowolnej topologii i dowolnego rzędu w ramach rozważanej klasy. W oparciu o opis macierzowy ogólnej struktury filtru OTA-C wyprowadzono ogólne formuły pozwalające na wyznaczanie i optymalizację szumów dowolnego filtru OTA-C. Przedstawione wyniki są użyteczne nie tylko dla klasycznych (dyskretnych lub...
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Optimization of impedance measurements using ‘chirp’ type perturbation signal
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Optimization of the geometry of the crankshaft for an internal combustion engine with heat regeneration
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Optimization of multiple model neural tracking filter for marine targets
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Variable-fidelity shape optimization of dual-rotor wind turbines
PublicationPurpose Dual-rotor wind turbines (DRWTs) are a novel type of wind turbines that can capture more power than their single-rotor counterparts. Because their surrounding flow fields are complex, evaluating a DRWT design requires accurate predictive simulations, which incur high computational costs. Currently, there does not exist a design optimization framework for DRWTs. Since the design optimization of DRWTs requires numerous model...
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Approximate Quality Criteria for Difficult Multi-Objective Optimization Problems
PublicationThis paper introduces approximate analytic quality criteria useful in assessing the efficiency of evolutionary multi-objective 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 state-of-the-art, in order to objectively assess the EMO performance in highly dimensional spaces; where some executive criteria,...
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RANS-based design optimization of dual-rotor wind turbines
PublicationPurpose An improvement in the energy efficiency of wind turbines can be achieved using dual rotors. Because of complex flow physics, the design of dual-rotor wind turbines (DRWTs) requires repetitive evaluations of computationally expensive partial differential equation (PDE) simulation models. Approaches for solving design optimization of DRWTs constrained by PDE simulations are investigated. The purpose of this study is to determine...
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Frequency-Based Regularization for Improved Reliability Optimization of Antenna Structures
PublicationThe paper proposes a modified formulation of antenna parameter tuning problem. The main ingredient of the presented approach is a frequency-based regularization. It allows for smoothening the functional landscape of the assumed cost function, defined to encode the prescribed design specifications. The regularization is implemented as a special penalty term complementing the primary objective and enforcing the alignment of the antenna...
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Approximate Criteria for the Evaluation of Truly Multi-Dimensional Optimization Problems
PublicationIn this paper we propose new improved approximate quality criteria useful in assessing the efficiency of evolutionary multi-objective optimization (EMO). In the performed comparative study we take into account the various EMO algorithms of the state-of-the-art, 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...
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Design Optimization of an Anisotropic Magnetoresistance Sensor for Detection of Magnetic Nanoparticles
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A distributed scheme for optimization of interdomain routing between collaborating domains
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Optimization of carbamazepine photodegradation on defective TiO2-based magnetic photocatalyst
PublicationIn this work, carbamazepine (CBZ) degradation over defective Fe3O4@SiO2/d-TiO2/Pt photocatalyst was studied. Within the titania structure, Ti vacancies and Pt nanoparticles were introduced to enhance the photocatalyst’s light absorption and influence charge carriers’ mobility. For the carbamazepine degradation, process parameters, e.g., temperature, flux intensity, photocatalyst loading, aeration, pH, and addition of H2O2, were optimized...
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Human Feedback and Knowledge Discovery: Towards Cognitive Systems Optimization
PublicationCurrent computer vision systems, especially those using machine learning techniques are data-hungry and frequently only perform well when dealing with patterns they have seen before. As an alternative, cognitive systems have become a focus of attention for applications that involve complex visual scenes, and in which conditions may vary. In theory, cognitive applications uses current machine learning algorithms, such as deep learning,...
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Arterial cannula shape optimization by means of the rotational firefly algorithm
PublicationThe article presents global optimization results of arterial cannula shapes by means of the newly modified firefly algorithm. The search for the optimal arterial cannula shape is necessary in order to minimize losses and prepare the flow that leaves the circulatory support system of a ventricle (i.e. blood pump) before it reaches the heart. A modification of the standard firefly algorithm, the so-called rotational firefly algorithm,...
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Spectrum-based modal parameters identification with Particle Swarm Optimization
PublicationThe paper presents the new method of the natural frequencies and damping identification based on the Artificial Intelligence (AI) Particle Swarm Optimization (PSO) algorithm. The identification is performed in the frequency domain. The algorithm performs two PSO-based steps and introduces some modifications in order to achieve quick convergence and low estimation error of the identified parameters’ values for multi-mode systems....
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Genetic Programming with Negative Selection for Volunteer Computing System Optimization
PublicationVolunteer computing systems like BOINC or Comcute are strongly supported by a great number of volunteers who contribute resources of their computers via the Web. So, the high efficiency of such grid system is required, and that is why we have formulated a multi-criterion optimization problem for a volunteer grid system design. In that dilemma, both the cost of the host system and workload of a bottleneck host are minimized. On...
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Reduction of Tire Rolling Resistance by Optimization of Road Surfaces and Tires
PublicationDuring interaction between tire and road surface three very important phenomena are always in effect. One of them (very desirable) is friction that is important for traction, braking and cornering. Two other phenomena are not desirable at all, that is rolling resistance and noise. This paper discusses relations between road surface and tire parameters versus tire rolling resistance. Road surface texture, porosity, impedance, strength...