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Interior Point Method Evaluation for Reactive Power Flow Optimization in the Power System
PublikacjaThe paper verifies the performance of an interior point method in reactive power flow optimization in the power system. The study was conducted on a 28 node CIGRE system, using the interior point method optimization procedures implemented in Power Factory software.
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Reliability assessment of truss towers using Monte Carlo Method, PEM and RSM
PublikacjaThe paper discusses reliability assessment of simple random truss structures using three different probabilistic methodologies: the Monte Carlo Method (MCM), the Point Estimate Method (PEM) and the Response Surface Method (RSM). A benchmark truss structure and a simplified full–size engineering tower are both analyzed. A set of ultimate load numerical calculations is performed and the results are taken as the basis of advanced...
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A Method for Underwater Wireless Data Transmission in a Hydroacoustic Channel under NLOS Conditions
PublikacjaWireless data transmission in the hydroacoustic channel under non-line-of-sight (NLOS) propagation conditions, for example, during a wreck penetration, is difficult to implement reliably. This is mostly due to the multipath propagation, which causes a reduction in the quality of data reception. Therefore, in this work an attempt has been made to develop a reliable method of wireless underwater communication test it under the NLOS...
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A Generalized SDP Multi-Objective Optimization Method for EM-Based Microwave Device Design
PublikacjaIn this article, a generalized sequential domain patching (GSDP) method for efficient multi-objective optimization based on electromagnetics (EM) simulation is proposed. The GSDP method allowing fast searching for Pareto fronts for two and three objectives is elaborated in detail in this paper. The GSDP method is compared with the NSGA-II method using multi-objective problems in the DTLZ series, and the results show the GSDP method...
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AgileSafe – a method of introducing agile practices into safety-critical software development processes
PublikacjaThis article introduces AgileSafe, a new method of incorporating agile practices into critical software development while still maintaining compliance with the software assurance requirements imposed by the application domain. We present the description of the method covering the process of its application and the input and output artefacts.
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Discrete Green's function approach to disjoint domain simulations in 3D FDTD method
PublikacjaA discrete Green’s function (DGF) approach to couple 3D FDTD subdomains is developed. The total-field/scattered-field subdomains are simulated using the explicit FDTD method whilst interaction between them is computed as a convolution of the DGF with equivalent current sources measured over Huygens surfaces. In the developed method, the DGF waveforms are truncated using the Hann’s window. The error varies in the range -65 to -40...
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A new diagnostic method for evaluation of cardiosurgery wound healing
PublikacjaOne of important and still unsolved problems in medicine is the question of objective and quantitative evaluation of post-surgery wound healing. The aim of this research is to analyse possibility and value of using the newly elaborated infrared imaging procedure – Active Dynamic Thermography (ADT) – for quantitative description of wound healing processes in cardiosurgery. Both, classical thermal figures of merit as well as ADT...
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A study of the kinetics of bismuth telluride synthesis by an oxide reduction method
PublikacjaThe kinetics of a reduction of bismuth and tellurium oxides in a hydrogen atmosphere, leading to the formation of thermoelectric bismuth telluride is investigated. The evaluation of the reaction kinetics was based on a thermogravimetric analysis performed in non-isothermal conditions. A non-parametric analysis method and the Friedman method were used for the evaluation of the data. Additionally, for a better understanding of the...
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Polynomial description of dynamic impedance spectrogram—introduction to a new impedance analysis method
PublikacjaThis paper presents a polynomial description of spectrograms obtained using Dynamic Electrochemical Impedance Spectroscopy. A method to fit the polynomial degree correctly is discussed. A simple electrical system of a diode connected in parallel with a capacitor was used for testing. Dynamic impedance measurements during potentiodynamic polarization were conducted. This paper presents an alternative analysis method that allows...
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Crank–Nicolson FDTD Method in Media Described by Time-Fractional Constitutive Relations
PublikacjaIn this contribution, we present the Crank-Nicolson finite-difference time-domain (CN-FDTD) method, implemented for simulations of wave propagation in media described by time-fractional (TF) constitutive relations. That is, the considered constitutive relations involve fractional-order (FO) derivatives based on the Grünwald-Letnikov definition, allowing for description of hereditary properties and memory effects of media and processes....
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Improvement of Fingerprinting Method based on Hill Cipher by using Frequency Domain
PublikacjaThe main goal of this paper is to present the advantages of a digital fingerprinting in a frequency domain over a pixel domain, in case of VoD services (Video on Demand). The paper presents basic issues of a multimedia data protection by digital fingerprinting. It also describes threats to embedded fingerprints from both collusion attacks and from a transmission itself. Possible solution was presented on the example of the DCT...
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Method of Decision-Making Logic Discovery in the Business Process Textual Data
PublikacjaGrowing amount of complexity and enterprise data creates a need for novel business process (BP) analysis methods to assess the process optimization opportunities. This paper proposes a method of BP analysis while extracting the knowledge about Decision-Making Logic (DML) in a form of taxonomy. In this taxonomy, researchers consider the routine, semi-cognitive and cognitive DML levels as functions of BP conceptual aspects of Resources,...
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OpenGL accelerated method of the material matrix generation for FDTD simulations
PublikacjaThis paper presents the accelerated technique of the material matrix generation from CAD models utilized by the finite-difference time-domain (FDTD) simulators. To achieve high performance of these computations, the parallel-processing power of a graphics processing unit was employed with the use of the OpenGL library. The method was integrated with the developed FDTD solver, providing approximately five-fold speedup of the material...
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Comparison of Air-Assisted, Vortex-Assisted and Ultrasound-Assisted Dispersive Liquid–Liquid Microextraction for the Determination of BTEX Compounds in Water Samples Prior to GC-FID Analysis
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Investigations of quasi-static vortex structures in 2D sand specimen under passive earth pressure conditions based on DEM and Helmholtz-Hodge vector field decomposition.
PublikacjaArtykuł przedstawia wyniki obliczeń quasi-statycznych struktur wirowych w 2-wymiarowej próbce piasku w warunkach pasywnego parcia gruntu. Zastosowano metodę elementów dyskretnych i dekompozycję Helmholtza-Hodge’a pola wektorowego. Stwierdzono bliską zależność między wirami a miejscem powstania strefy lokalizacji odkształceń stycznych.
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Method of selecting programming practices for the safety-critical software development projects
PublikacjaIn recent years a plan-driven approach traditionally used in safety-critical software development has been put to a test by rapidly changing technologies, more diverse group of clients and volatile market requirements. The need to deliver good quality systems, faster and at lower cost in comparison to competitors encouraged companies to look for more efficient solutions. Agile methodologies are known to successfully address these...
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A Novel Bitrate Adaptation Method for Heterogeneous Wireless Body Area Networks
PublikacjaIn the article, a novel bitrate adaptation method for data streams allocation in heterogeneous Wireless Body Area Networks (WBANs) is presented. The efficiency of the proposed algorithm was compared with other known algorithms of data stream allocation using computer simulation. A dedicated simulator has been developed using results of measurements in the real environment. The usage of the proposed adaptive data streams allocation...
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Reliability Analysis of Sea Cliff Slope Stability by Point Estimate Method
PublikacjaThe paper presents a reliability analysis of a sea cliff slope. The cliff, located in Jastrzębia Góra, is characterised by a complicated geological structure. Although currently stable, it is in fact close to the limit state. The objective of this paper is to present the point estimate method (PEM) of determining the mean value and standard deviation of the safety factor of the slope. Assuming its normal distribution, these statistical...
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Reliability Analysis of Sea Cliff Slope Stability by Point Estimate Method
PublikacjaThe paper presents a reliability analysis of a sea cliff slope. The cliff, located in Jastrzębia Góra, is characterised by a complicated geological structure. Although currently stable, it is in fact close to the limit state. The objective of this paper is to present the point estimate method (PEM) of determining the mean value and standard deviation of the safety factor of the slope. Assuming its normal distribution, these statistical...
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A Novel Bitrate Adaptation Method for Heterogeneous Wireless Body Area Networks
PublikacjaIn the article, a novel bitrate adaptation method for data streams allocation in heterogeneous Wireless Body Area Networks (WBANs) is presented. The efficiency of the proposed algorithm was compared with other known algorithms of data stream allocation using computer simulation. A dedicated simulator has been developed using results of measurements in the real environment. The usage of the proposed adaptive data streams allocation...
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A dressing method in mathematical physics
PublikacjaMetodę ubierania stosuje się do równań nieliniowych całkowalnych i w teorii potencjałów całkowalnych mechaniki kwantowej.
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Parallelization Method for a Continuous Property
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Detection of the First Component of the Received LTE Signal in the OTDoA Method
PublikacjaIn a modern world there is a growing demand for localization services of various kinds. Position estimation can be realized via cellular networks, especially in the currently widely deployed LTE (Long Term Evolution) networks. However, it is not an easy task in harsh propagation conditions which often occur in dense urban environments. Recently, time-methods of terminal localization within the network have been the focus of attention,...
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FDTD Method for Electromagnetic Simulations in Media Described by Time-Fractional Constitutive Relations
PublikacjaIn this paper, the finite-difference time-domain (FDTD) method is derived for electromagnetic simulations in media described by the time-fractional (TF) constitutive relations. TF Maxwell’s equations are derived based on these constitutive relations and the Grünwald–Letnikov definition of a fractional derivative. Then the FDTD algorithm, which includes memory effects and energy dissipation of the considered media, is introduced....
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A method of RTS noise identification in noise signals of semiconductor devices in the time domain
PublikacjaIn the paper a new method of Random Telegraph Signal (RTS) noise identification is presented. The method is based on a standardized histogram of instantaneous noise values and processing by Gram-Charlier series. To find a device generating RTS noise by the presented method one should count the number of significant coefficients of the Gram-Charlier series. This would allow to recognize the type of noise. There is always one (first)...
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Proposal of a method for effective tasks distribution in the execution of compolex problems
PublikacjaAn access to a great number of various services allows for decomposition of complex problems into smaller and less complex tasks. Those tasks can be presented in a form of a dependency graph. This paper shows an idea of executing such a problem using cooperating autonomous agents. Main focus of this work is cooperation covering effective tasks distribution among executors. This paper presents an algorithm for dynamic executor selection...
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DiSTFAG method robust to gross errors in monitoring displacements and strains in unstable reference systems
PublikacjaThe DiSTFA method (Displacements and Strains using Transformation and Free Adjustment) was presented in Kamiński (2009). The method has been developed for the determination of displacements and strains of engineering objects in unstable reference systems, as well as for examining the stability of reference points. The DiSTFAG (Gross errors) method presented in the paper is the extension of the DiSTFA method making it robust to...
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Bearing capacity of working platform using distinct layout optimization method
PublikacjaBearing capacity of the working platforms from sandy soil resting on NC and OC clays was analyzed using LimitState GEO program. Different failure modes are considered using distinct layout optimization (DLO) method, which forms the upper bound solution of limit state analysis. Different mechanisms of failure were observed as a function of the platform thickness, angle of internal friction of the platform material and undrained...
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An Efficient Simulation Method of Massive MIMO Antenna Arrays used in 5G Mobile Phones
PublikacjaThis paper deals with a model-order reduction method, applied to speed-up the simulations of MIMO antenna arrays, performed by means of finite element method. The obtained results of the numerical tests show that the described technique is reliable and considerably increases the efficiency of the standard finite element method.
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INTEGRATED FUNCTIONAL SAFETY AND CYBERSECURITY ANALYSIS METHOD FOR SMART MANUFACTURING SYSTEMS
PublikacjaThis article addresses integrated functional safety and cybersecurity analysis with regard to: the generic functional safety standard IEC 61508 and the cyber security standard IEC 62443 concerning an industrial automation and control system (IACS). The objective is to mitigate the vulnerability of information technology (IT) and operational technology (OT) systems, and reduce relevant risks taking into account a set of fundamental...
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Hybrid Multi-Criteria Method of Analyzing the Location of Distributed Renewable Energy Sources
PublikacjaThis paper presents the development and the application of a hybrid multi-criteria method, the combination of the Analytic Hierarchy Process (AHP), and numerical taxonomy (NT),to support the decision making on the location of distributed renewable energy sources meetingvarious types of assessment criteria. Finding criteria weights, using the AHP method, eliminates thedisadvantage of NT—which, in current form, is defined by its...
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Noninvasive method for rotor fault diagnosis in inverter fed induction motor drive
PublikacjaThis article presents a proposal, simulation and experimental results of a noninvasive rotor fault diagnosis method for the inverter fed induction motor drive. Comparing to reported methods the proposed one does not require any load, rotor brake, slip, mechanical or electrical system physical modification e.g. machine disassembly and can be applied regardless the rotor speed measurement or estimation method.
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Macromodels for Efficient Analysis of Open-Region Problems Using the Finite Element Method
PublikacjaThis paper presents a local model-order reduction, called macromodeling, applied to speed-up the simulations of open-region problems, analyzed by means of finite element method. This technique is illustrated by a numerical example, which deals with a dielectric resonator antenna (DRA). The obtained results show that the proposed approach is reliable and can significantly increase the standard finite element method efficiency.
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Wideband Model Order Reduction for Macromodels in Finite Element Method
PublikacjaAbstract: This paper presents a novel algorithm for accelerating 3D Finite Element Method simulations by introducing macromodels created in local model order reduction in the selected subdomains of the computational domain. It generates the projection basis for a compact system of equations associated with a separate subdomain. Due to non-linear frequency dependency in the Right Hand Side (RHS), the standard reduction methods do...
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SAILING ROUTE PLANNING METHOD CONSIDERING VARIOUS USER CATEGORIES
PublikacjaThe article describes the methodology related to determining the multi-criteria routes for sailing ships. Details of sea area discretisation and discretisation of the description of the sailing vessel properties and manoeuvring principles are shown. User requirements were specified (for five different categories of users) and on this basis the criteria for selecting the most suitable shipping route were formulated. The presented...
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Active dynamic thermography method for TRAM flap blood perfusion mapping in breast reconstruction
PublikacjaThis paper presents the new method of the transverse rectus abdominis musculocutaneous flap blood perfusion mapping based on the active dynamic thermography. The method is aimed at aiding a surgeon during breast reconstruction procedure. A pair of dTnorm and t90_10 parameters were used as parametric image descriptors of the flap blood perfusion. The method was tested on 38 patients that were subjected to breast reconstruction procedure....
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A new viscoelastic method of calculation of low-temperature thermal stresses in asphalt layers of pavements
PublikacjaThe paper presents a new method of calculation of thermal stresses in asphalt layers of pavements induced by cooling or heating. The method, developed by the author, is based on the analytical solution for the linear viscoelastic Burgers model extended numerically for the case of asphalt layers whose rheological parameters are strongly dependent on temperature. The coefficient of thermal expansion and Poisson’s ratio may optionally...
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Investigation method of large-volume tire with mobile test rig
PublikacjaThe goal of this research is to develop the tire test method and mobile tire test rig. The test rig enables measurement of tire properties as stiffness and viscous damping in vertical direction, and tire–ground characteristics on the asphalt rigid surface. The tire-ground characteristics are measured by force and a torque measurement hub. The design, calibration and the algorithm for calculating the forces in the wheel center are...
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A method to synthesise groove cam Geneva mechanisms with increased dwell period
PublikacjaThe present study develops a method to synthesise the groove cam Geneva mechanism with increased dwell period. The main condition of the synthesis is to provide the desired law of motion of the wheel. Additional synthesis conditions are the limitation of the maximum pressure angle and the limitation of the minimum curvature radius of the cam profile. Unlike the conventional Geneva mechanisms, the synthesised groove cam Geneva mechanisms...
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APPLICATION OF THE KOSECKI’S METHOD IN DESIGNING OF OFFSHORE WIND POWER PLANTS FOUNDATION
PublikacjaThe concept of offshore wind power plants has been well developed in many European countries. There is no such thing as design of offshore wind power plants according to national tradition. The main problem is the lack of standards and guidelines. Ones being applied are Scandinavian or American methods which are not fully adapted to the conditions of the Baltic Sea. The article focuses on the monopile design, as it is currently the...
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The analytical design method of railway route’s main directions intersection area
PublikacjaThe paper presents a design method related to railway track sections situated in a bend. In the method advantage is taken of an analytical form of description by using appropriate mathematical formulae. This may becomeparticularly usefulwhen the investigations are based on the data obtained from mobile satellite measurements. In the paper attention is concentrated on an universal approach creating an opportunity to diversify the...
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Novel method of lung area extraction in chest perfusion computed tomography
PublikacjaChest perfusion computed tomography (pCT) is a useful technique in the medical diagnosis of how organs function. Perfusion CT scans are used to calculate perfusion parameters. In the case of automated methods of lung perfusion parameters calculation, the prior extraction of the lung area is desired to avoid unnecessary calculation in an area outside the lung cross-section and to avoid wasting time on processing signals of no diagnostic...
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Parametrical Method for Determining Optimal Ship Carrying Capacity and Performance of Handling Equipment
PublikacjaThe paper presents a method of evaluating the optimal value of the cargo ships deadweight and the coupled optimal value of cargo handling capacity. The method may be useful at the stage of establishing the main owners requirements concerning the ship design parameters as well as for choosing a proper second hand ship for a given transportation task. The deadweight and the capacity are determined on the basis of a selected economic...
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Velocity measurement using the fdoa method in ground-based radio navigation system
PublikacjaVelocity is one of the main navigation parameters of the moving objects. However some systems of position estimation using radio wave measurements cannot provide velocity data due to limitation of their performance. In this paper a velocity measurement method for DS-CDMA radio navigation system is proposed, which doesn’t require full synchronization of reference stations carrier frequencies. The article presents basics of FDOA...
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Efficient method for octahedral NH2-MIL-125 (Ti) synthesis: Fast and mild conditions
PublikacjaA new hot injection method for preparing octahedral NH2-MIL-125 (Ti) was developed. This method is six times faster and conducted under milder conditions, i.e., at 120°C in a flask, and exhibits higher crystal formation efficiency than the commonly used solvothermal method while maintaining comparable structural, optical, and photocatalytic properties.
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Receiver-side fingerprinting method for color images based on a series of quaternion rotations
PublikacjaThe proposed method is a new Joint Fingerprinting and Decryption (JFD) method that uses a cipher based on quaternion rotation to encrypt color images that are then sent to all users via multicast transmission. Individual encryption keys depend on the users’ fingerprints, so that a unique fingerprint is introduced into the image during decryption for each decryption key. A simulation-based research was conducted to examine the method’s...
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A method of determination of electrical conduction mechanisms in complex amorphous materials
PublikacjaA novel approach to determine conduction mechanisms in complex amorphous materials was presented and tested on a real system. In the first step of the presented method, total electrical admittance of the material is analyzed in order to separate a couple of processes, each of which can be described by Jonscher's universal dielectric response. In the following step, a temperature dependence of dielectric response parameters of the...
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Matrix-based robust joint fingerprinting and decryption method for multicast distribution of multimedia
PublikacjaThis paper addresses the problem of unauthorized redistribution of multimedia content by malicious users (pirates). The solution proposed here is a new joint fingerprinting and decryption method which meets the requirements for both imperceptibility and robustness of fingerprints and scalability in terms of design and distribution of fingerprinted multimedia content. The proposed method uses a simple block cipher based on matrix...
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Quechers sample preparation method variants for analysis of pesticide residues in fruits and vegetables
PublikacjaThis article describes the comparison of different versions of an easy, rapid and low-cost sample preparation approach for the determination of pesticide residues in fruits and vegetables by concurrent use of gas and liquid chromatography coupled to MS or ECD for detection. The sample preparation approach is known as QuEChERS, which stands for quick, easy, cheap, effective, rugged and safe. It is a combination of liquid-liquid...
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Structural reliability of overhead power lines by means of Monte Carlo Method and RSM
PublikacjaThe article discusses the issue of reliability assessment of overhead power lines by means of both Monte Carlo Method and Response Surface Method. The suspension tower OS24 ON150+10 is considered, as the weakest element of the line. A comparison is made between deterministic and probabilistic approaches to wind and icing loading. The PDFs for wind and icing loads are proposed. Reliability is assessed for both critical atmospheric...