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Search results for: SAILING VESSELS, WEATHER ROUTING, EVOLUTIONARY MULTI-OBJECTIVE OPTIMIZATION, WEATHER FORECASTS, NAVIGATION
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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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Optimization of the Hardware Layer for IoT Systems using a Trust Region Method with Adaptive Forward Finite Differences
PublicationTrust-region (TR) algorithms represent a popular class of local optimization methods. Owing to straightforward setup and low computational cost, TR routines based on linear models determined using forward finite differences (FD) are often utilized for performance tuning of microwave and antenna components incorporated within the Internet of Things systems. Despite usefulness for design of complex structures, performance of TR methods...
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Expedited Globalized Antenna Optimization by Principal Components and Variable-Fidelity EM Simulations: Application to Microstrip Antenna Design
PublicationParameter optimization, also referred to as design closure, is imperative in the development of modern antennas. Theoretical considerations along with rough dimension adjustment through supervised parameter sweeping can only yield initial designs that need to be further tuned to boost the antenna performance. The major challenges include handling of multi-dimensional parameter spaces while accounting for several objectives and...
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Towards a reliable method for extrapolation of propulsion performance for vessels with twin-crp-pod system
PublicationThe study presents power performance prediction of an Ultra Large Container Ship (ULCS) with hybrid twin-crp-pod propulsion system. Twin crp-pod propulsion system is a combination of three concepts: twin screw, contra-rotating propellers (crp) and conventional shaft propellers with pod propulsors behind. The presented study shows the current extrapolation method for crp propulsion systems and tries to point out its weaknesses....
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A Novel Trust-Region-Based Algorithm with Flexible Jacobian Updates for Expedited Optimization of High-Frequency Structures
PublicationSimulation-driven design closure is mandatory in the design of contemporary high-frequency components. It aims at improving the selected performance figures through adjustment of the structure’s geometry (and/or material) parameters. The computational cost of this process when employing numerical optimization is often prohibitively high, which is a strong motivation for the development of more efficient methods. This is especially...
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Rapid design optimization of antennas using variable-fidelity EM models and adjoint sensitivities
PublicationPurpose – Development of techniques for expedited design optimization of complex and numerically expensive electromagnetic (EM) simulation models of antenna structures validated both numerically and experimentally. The paper aims to discuss these issues. Design/methodology/approach – The optimization task is performed using a technique that combines gradient search with adjoint sensitivities, trust region framework, as well as...
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The new investing effectiveness evaluation multi-criteria method in modern supply systems
PublicationThe important problem in the processes of modelling and programming the development of sustainable energy sector is the multi-criteria manner of assessing the effectiveness of investments. The goal of this paper is to show how to take into account the impact of investments in multidimensional modelling decision-making processes. This goal can be achieved through the development, presentation, and use of a new multi-criteria method...
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Optimization of the efficiency of braking energy recovery in rail transport by changing arrival time
PublicationThe article refers to the previous work of the authors, in which the model of traffic organization of cooperating trains including the optimization of the use of energy returned to the catenary was presented. In the presented article, the model was modified by changing the main control variable, which affects the efficient use of energy. Departure time was changed for the arrival time of the train to the stop or station. The optimization...
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Pareto Task Assignments by an Adaptive Quantum-based Evolutionary Algorithm AQMEA
PublicationW pracy scharakteryzowano state_of_the_art w zakresie kwantowych algorytmów ewolucyjnych. Scharakteryzowano zasady efektywnego projektowania tej klasy algorytmów genetycznych. Podano wyniki uzyskane za pomocą kwantowego algorytmu ewolucyjnego AQMEA w zakresie wyznaczanie przydziałów zadań optymalnych w sensie Pareto.
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Search safe ship trajectories in collision situation at sea by evolutionary computation
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Evolutionary - fuzzy hybrid system of steering the moveable object in dynamic environment
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A design framework for rigorous constrained EM-driven optimization of miniaturized antennas with circular polarization
PublicationCompact radiators with circular polarization are important components of modern mobile communication systems. Their design is a challenging process which requires maintaining simultaneous control over several performance figures but also the structure size. In this work, a novel design framework for multi-stage constrained miniaturization of antennas with circular polarization is presented. The method involves sequential optimization...
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An application of multi-agent system for ship’s power systems design
PublicationDesign process of transport ship power system consists of structure (topology) and component elements selection. Compliance with the requirements for static components does not guarantee optimal dynamic characteristics of entire power system. Design steps are difficult to formalize and as a consequence to this reason expert and multi-agent systems are used for solving selected design issues. In the paper distributed multi-agent...
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Ranking of Generation Source Locations by a Hybrid Multi-Criteria Method
PublicationThe paper presents a ranking of the locations of eight renewable energy sources (RES) made using a hybrid multi-criteria analysis method. The method is a combination of the analytical hierarchical process (AHP) method and numerical taxonomy. The considered generating sources, i.e. solar plants, biogas plants, and wind farms are sources that will significantly contribute to implementing the provisions of the energy and climate package...
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Compact broadband multi-way 1:6 power divider
PublicationThis paper introduces a design flow of a microstrip multi-way 1:6 power divider incorporating photonic bandgap (PBG) structures. Themethod proposed has enabled the achievement of considerable miniaturization (15%) together with transmission characteristics enhancement(141% bandwidth). Measured results show significant similarity to theoretical characteristics, which proves the attractiveness of presented design methodology.
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History-based dynamic weight voting for multi-agent systems
PublicationTaking decision in multi-agent systems may involve voting. Two basic voting protocols are surveyed in the paper. Then, a new history-based dynamic weight voting is proposed. This voting protocol allows for identification of the agents which contribute to the correct system decision. The proposed solution is contrasted with majority voting and with weighted average voting, to show its advantages
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Magnetic signature reproduction of ferromagnetic ships at arbitrary geographical position, direction and depth using a multi-dipole model
PublicationThe reproduction of magnetic signatures is an important issue concerning the safety of ship traffic, as well as the identification and classification of vessels. Moreover, military applications of magnetic signatures and their reproduction refer to the activation or protection against activation of magnetic naval mines. Previous works on this subject focused on recording and replicating the signatures under the same conditions...
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Multi-region fuzzy logic controller with local PID controllers for U-tube steam generator in nuclear power plant
PublicationIn the paper, analysis of multi-region fuzzy logic controller with local PID controllers for steam generator of pressurized water reactor (PWR) working in wide range of thermal power changes is presented. The U-tube steam generator has a nonlinear dynamics depending on thermal power transferred from coolant of the primary loop of the PWR plant. Control of water level in the steam generator conducted by a traditional PID controller...
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Application of the simplified models to inverse flood routing in upper Narew river(Poland)
PublicationW pracy przedstawiono rozwiązanie zagadnienia odwrotnej transformacji przepływów z zastosowaniem uproszczonych modeli. Zastosowano model fali kinematycznej oraz równanie retencji. W pierwszym przypadku równanie całkowano w kierunku malejącego czasu zaś w drugim w kierunku przeciwnym do przepływu. Wykazano, że obydwa podejścia są równoważne. Modele zastosowano dla górnego odcinka Narwi.
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Adaptive Hyperparameter Tuning within Neural Network-based Efficient Global Optimization
PublicationIn this paper, adaptive hyperparameter optimization (HPO) strategies within the efficient global optimization (EGO) with neural network (NN)-based prediction and uncertainty (EGONN) algorithm are proposed. These strategies utilize Bayesian optimization and multiarmed bandit optimization to tune HPs during the sequential sampling process either every iteration (HPO-1itr) or every five iterations (HPO-5itr). Through experiments using...
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Implementation of multi-operand addition in FPGA using high-level synthesis
PublicationThe paper presents the results of high-level synthesis (HLS) of multi-operand adders in FPGA using the Vivado Xilinx environment. The aim was to estimate the hardware amount and latency of adders described in C-code. The main task of the presented experiments was to compare the implementations of the carry-save adder (CSA) type multi-operand adders obtained as the effect of the HLS synthesis and those based on the basic component...
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Rapid design optimization of compact couplers using response features and adjoint sensitivities
PublicationA technique for rapid EM-driven design optimization of compact microwave couplers is presented. Our approach exploits response features and adjoint sensitivities and allows for low-cost design closure both in terms of performance enhancement and structure miniaturization. It is demonstrated using a compact rat-race coupler working at 1 GHz and compared to adjoint-based gradient optimization.
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MSIS Image Postioning in Port Areas with the Aid of Comparative Navigation Methods
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Towards a decision support system for maritime navigation on heavily trafficked basins
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Using Rule-Based System for Monitoring Marine Navigation Data Processing
PublicationProcessing marine navigational data requires sophisticated software solutions. Typically, specialized tools called processors are analyzing raw data from different sensors. It becomes important to create the monitoring software that is able to validate and verify processing components integrated into the final system. Drools®business rule management platform provides a core business rules engine, web authoring and rules management...
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A navigation device utilizing body communication channel for mobile wearable systems
PublicationA novel touch sensor utilizing a body communication technology is presented in the paper. The proposed device accepts orders (gestures) only from a person wearing it. Moreover, when comparing it to a similar, however an optical one, it appears as a less power consumable. Preliminary results of its properties examination are presented and discussed. Additionally, the developed sensor allows to measure a human body the electrical...
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Performance Analysis and Quantification of BeiDou Navigation Satellite System (BDS-3)
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A parametric method for preliminary determining of mass characteristics of inland navigation ships
PublicationPrzedstawiono metodę którą opracowano, wykorzystując algorytmy realizujące zalecenia zawarte w Przepisach Klasyfikacji i Budowy Statków Śródlądowych PRS-u, oraz zastosowano uproszczoną metodę wyznaczania mas usztywnień poszycia kadłuba. Metoda wymiarowania oparta na tym algorytmie dotyczy klasycznych statków służących do przewozu drobnicy, ładunków masowych i płynnych - określających zakres stosowania metody. Metoda nie obejmuje...
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Exploiting multi-interface networks: Connectivity and Cheapest Paths
PublicationLet G = (V,E) be a graph which models a set of wireless devices (nodes V) that can communicate by means of multiple radio interfaces, according to proximity and common interfaces (edges E). The problem of switching on (activating) the minimum cost set of interfaces at the nodes in order to guarantee the coverage of G was recently studied. A connection is covered (activated) when the endpoints of the corresponding edge share at...
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Expedited Optimization of Passive Microwave Devices Using Gradient Search and Principal Directions
PublicationOver the recent years, utilization of numerical optimization techniques has become ubiquitous in the design of high-frequency systems, including microwave passive components. The primary reason is that the circuits become increasingly complex to meet ever growing performance demands concerning their electrical performance, additional functionalities, as well as miniaturization. Nonetheless, as reliable evaluation of microwave device...
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Multicriteria Optimization Approach to Design and Operation of District Heating Supply System over its Life Cycle
PublicationDistrict Heating (DH) systems are commonly supplied using local heat sources. Nowadays, modern insulation materials allow for effective and economically viable heat transportation over long distances (over 20 km). In the paper a method for optimized selection of design and operating parameters of long distance Heat Transportation System (HTS) is proposed. The method allows for evaluation of feasibility and effectivity of heat transportation...
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Head movement compensation algorithm in multi-display communication by gaze
PublicationAn influence of head movements on the gaze estimation accuracy when using a head mounted eye tracking system is discussed in the paper. This issue has been examined for a multi-display environment. It was found that head movement (rotation) to some extent does not influence on the gaze estimation accuracy seriously. Acceptable results were obtained when using eye-tracker to communicate with a computer via in two displays simultaneously.
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Efficient knowledge-based optimization of expensive computational models using adaptive response correction
PublicationComputer simulation has become an indispensable tool in engineering design as they allow an accurate evaluation of the system performance. This is critical in order to carry out the design process in a reliable manner without costly prototyping and physical measurements. However, high-fidelity computer simulations are computationally expensive. This turns to be a fundamental bottleneck when it comes to design automation using numerical...
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Multi-Criterial Design of Antennas with Tolerance Analysis Using Response-Feature Predictors
PublicationImperfect manufacturing is one of the factors affecting the performance of antenna systems. It is particularly important when design specifications are strict and leave a minimum leeway for a degradation caused by geometry or material parameter deviations from their nominal values. At the same time, conventional antenna design procedures routinely neglect to take the fabrication tolerances into account, which is mainly a result...
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A new multi-process collaborative architecture for time series classification
PublicationTime series classification (TSC) is the problem of categorizing time series data by using machine learning techniques. Its applications vary from cybersecurity and health care to remote sensing and human activity recognition. In this paper, we propose a novel multi-process collaborative architecture for TSC. The propositioned method amalgamates multi-head convolutional neural networks and capsule mechanism. In addition to the discovery...
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Multi-Channel Virtual Instrument for Measuring Temperature—A Case Study
PublicationThe article presents the hardware and software configuration of the developed multi-channel temperature measurement system as well as calibration procedures and measurement results verifying the properties of measurement channels. The system has been developed and dedicated primarily for measuring the temperature distribution in a laboratory model simulating underground power lines. With the adopted configuration of the analog...
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Adaptive Method for Modeling of Temporal Dependencies between Fields of Vision in Multi-Camera Surveillance Systems
PublicationA method of modeling the time of object transition between given pairs of cameras based on the Gaussian Mixture Model (GMM) is proposed in this article. Temporal dependencies modeling is a part of object re-identification based on the multi-camera experimental framework. The previously utilized Expectation-Maximization (EM) approach, requiring setting the number of mixtures arbitrarily as an input parameter, was extended with the...
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Example of Using Particle Swarm Optimization Algorithm with Nelder–Mead Method for Flow Improvement in Axial Last Stage of Gas–Steam Turbine
PublicationThis article focuses principally on the comparison baseline and the optimized flow efficiency of the final stage of an axial turbine operating on a gas–steam mixture by applying a hybrid Nelder– Mead and the particle swarm optimization method. Optimization algorithms are combined with CFD calculations to determine the flowpaths and thermodynamic parameters. The working fluid in this study is a mixture of steam and gas produced...
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Multi-level governance w procesie ustanowienia Wymiaru Północnego Unii Europejskiej
PublicationArtykuł ukazuje proces podejmowania decyzji w celu ustalenia Wymiaru Północnego w kontekście multi-level governance. Analiza koncentruje się na instytucjonalnych i proceduralnych aspektach wertykalnego przekazania władzy. Jej wyniki wykazały właściwości wielopoziomowego sprawowania rządów w fazie powołania zewnętrznej inicjatywy makroregionalnej Unii Europejskiej. Pozwoliły one także na włączenie się do debaty na temat możliwości...
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Reliability And Safety As An Objective Of Intelligent Transport Systems In Urban Areas
PublicationTechnologies that use transport telematics offer tools for strengthening urban transport systems. They rationalise the use of the existing infrastructure and transport management systems, increase their reliability and safety and improve the transport behaviour of residents, while reducing the operating costs of transport. The main reason for using Intelligent Transport Systems (ITS) is the need to implement measures to reduce...
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Subjective Interpretation and Objective Evaluation of Blackout Fabric’s Barrier Properties
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Development of visual evoked potentials detection algorithm for objective perimetry
PublicationOpisano nową propozycję algorytmu detekcji potencjałów wzrokowych w zapisie EEG. Nowy algorytm bazuje na dekompozycji statystycznej ICA. Algorytm wstępnie przetestowano na danych eksperymentalnych.
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A hybrid approach to optimization of radial inflow turbine with principal component analysis
PublicationEnergy conversion efficiency is one of the most important features of power systems as it greatly influences the economic balance. The efficiency can be increased in many ways. One of them is to optimize individual components of the power plant. In most Organic Rankine Cycle (ORC) systems the power is created in the turbine and these systems can benefit from effective turbine optimization. The paper presents the use of two kinds...
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Determining the optimal course alteration maneouvre in a multi-target encounter situation for a given ship domain model
PublicationW artykulee przedstawiono nową deterministyczną metodę wyznaczania niezbędnego manewru kursem dla sytuacji spotkania z wieloma obiektami obcymi i dla dowolnej zadanej domeny. Jej prostota i niska złożoność obliczeniowa czynią ją dobrą alternatywą dla obecnie stosowanych metod. Główny algorytm został przedstawiony wprost, tak aby mógł być bezpośrednio zastosowany w pokładowych systemach antykolizyjnych lub w systemach VTS.
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Improving Output Performance of the Ultrasonic Multicell Piezoelectric Motor by Development the Multi-Rotor Structure
PublicationIn recent years, many researches have been carried out on piezoelectric multi-rotor structures. This paper describes the analysis, development and experimental process of an ultrasonic multi-cell piezoelectric motor using a multi-rotor structure. In this design, three independent cells have been integrated into a mechatronic system. Analytical model and finite element method are used for modal and dynamic analysis of the proposed...
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Dissociative multi-photon ionization of isolated uracil and uracil-adenine complexes
PublicationRecent multi-photon ionization (MPI) experiments on uracil revealed a fragment ion at m/z 84 that was proposed as a potential marker for ring opening in the electronically excited neutral molecule. The present MPI measurements on deuterated uracil identify the fragment as C3H4N2O+ (uracil+ less CO), a plausible dissociative ionization product from the theoretically predicted open-ring isomer. Equivalent measurements on thymine...
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Optimization of liquid chromatographic separation of pharmaceuticals within green analytical chemistry framework
PublicationThe contribution is aimed at the development of methodology that allows to consider green analytical chemistry criteria during optimization of liquid chromatographic separation with design of experiment. The objectives of the optimization are maximization of peak areas of five non-steroid anti-inflammatory drugs, maximization of resolution between peaks, with simultaneous shortening of chromatographic separation time and minimization...
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Expedited optimization of antenna input characteristics with adaptive Broyden updates
PublicationSimulation-driven adjustment of geometry and/or material parameters is a necessary step in the design of contemporary antenna structures. Due to their topological complexity, other means, such as supervised parameter sweeping, does not usually lead to satisfactory results. On the other hand, rigorous numerical optimization is computationally expensive due to a high cost of underlying full-wave electromagnetic (EM) analyses, otherwise...
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Cost-efficient design optimization of compact patch antennas with improved bandwidth
PublicationIn this letter, a surrogate-assisted optimization procedure for fast design of compact patch antennas with enhanced bandwidth is presented. The procedure aims at addressing a fundamental challenge of the design of antenna structures with complex topologies, which is simultaneous adjustment of numerous geometry parameters. The latter is necessary in order to find a truly optimum design and cannot be executed-at the level of high-fidelity...
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Fast simulation-driven design optimization of UWB band-notch antennas
PublicationIn this letter, a simple yet reliable and automated methodology for rapid design optimization of ultra-wideband (UWB) band-notch antennas is presented. Our approach is a two-stage procedure with the first stage focused on the design of the antenna itself, and the secondstage aiming at identification of the appropriate dimensions of the resonator with the purpose of allocating the band-notch in the desired frequency range. For the...