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Applicability of phenolic acids as effective enhancers of cocrystals solubility of methylxanthines
PublicationApplicability of phenolic acids as potential cocrystal formers for methylxanthine derivatives was analyzed both in terms of cocrystallization probabilities and solubility advantage. The cocrystal formation abilities were evaluated using mixing enthalpy estimated within the conductor like screening model for real solvents (COSMO-RS) framework. The solubility improvement of potential cocrystals was estimated by formulation of the...
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Sustainable synthesis of cyclic carbonates from bio‐based polyether polyol: the structure characterization, rheological behaviour and thermal properties
PublicationThe cycloaddition of CO2 to epoxides represents a green efficient method to form bis(cyclic carbonate)s. The main purpose of the work reported in this paper was to examine the effect of the gas flow rate (20, 40, 60 and 100 mL min–1) during carbonation on the conversion yield, chemical structure, rheological behaviour and thermal properties of the prepared compounds. A series of new bis(cyclic carbonate)s was obtained from bio‐based...
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Mangiferin: A comprehensive review on its extraction, purification and uses in food systems
PublicationWith the target of fabricating healthier products, food manufacturing companies look for natural-based nutraceuticals that can potentially improve the physicochemical properties of food systems while being nutritive to the consumer and providing additional health benefits (biological activities). In this regard, Mangiferin joins all these requirements as a potential nutraceutical, which is typically contained in Mangifera indica...
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Morphology control through the synthesis of metal-organic frameworks
PublicationDesignable morphology and predictable properties are the most challenging goals in material engineering. Features such as shape, size, porosity, agglomeration ratio significantly affect the final properties of metal- organic frameworks (MOFs) and can be regulated throughout synthesis parameters but require a deep under- standing of the mechanisms of MOFs formation. Herein, we systematically summarize the effects of the indi- vidual...
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Modal FEM Analysis of Ferrite Resonant Structures
PublicationThe finite-element method (FEM) is applied for modal analysis of ferrite-loaded spherical resonators. To improve the efficiency of the numerical calculations, the body-of-revolution (BOR) technique is utilized. Due to the frequency-dependent ferrite permeability, FEM leads to a nonlinear eigenvalue problem that is challenging to solve. To this end, Beyn’s method is proposed. The effectiveness of the proposed approach is confirmed...
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Linear Micropolar Elasticity Analysis of Stresses in Bones Under Static Loads
PublicationWe discuss the finite element modeling of porous materials such as bones using the linear micropolar elasticity. In order to solve static boundary-value problems, we developed new finite elements, which capture the micropolar behavior of the material. Developed elements were implemented in the commercial software ABAQUS. The modeling of a femur bone with and without implant under various stages of healing is discussed in details
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Analiza porównawcza sposobów wyznaczania obciążeń wiatrem na podstawie norm projektowych i analizy przepływu CFD
PublicationW pracy poruszono tematykę wykorzystania analizy przepływu CFD do wyznaczania obciążeń wiatru na konstrukcje. Przedstawiono analizę trzech modeli budynków o dachu dwuspadowym o różnych kątach nachylenia, dla których dokonano porównania wielkości współczynników parcia z wynikami dostępnymi w literaurze. Obliczenia analityczne wykonano zgodnie z normą z PN-EN 1991-1-4, natomiast obliczenia numeryczne wykonano w programie R-Wind Simulation....
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On the impact of Big Data and Cloud Computing on a scalable multimedia archiving system
PublicationMultimedia Archiver (MA) is a system build upon the promise and fascination of the possibilities emerging from cloud computing and big data. We aim to present and describe how the Multimedia Archiving system works for us to record, put in context and allow a swift access to large amounts of data. We introduce the architecture, identified goals and needs taken into account while designing a system processing data with Big Data...
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Experiment-aided virtual prototyping to minimize tool-workpiece vibration during boring of large-sized structures
PublicationThe paper presents the author's method of solving the problems of vi-bration suppression during boring of large-sized workpieces by means of an in-novative method of adjusting the rotational speed of the boring bar. It consists in selecting the spindle speed in accordance with the results of the cutting process simulation. The method includes identification of the model of the finite element method of the boring bar. The Root Mean...
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A novel genetic approach to provide differentiated levels of service resilience in IP-MPLS/WDM networks
PublicationThis paper introduces a novel class-based method of survivable routing for connection-oriented IP-MPLS/WDM networks, called MLS-GEN-H. The algorithm is designed to provide differentiated levels of service survivability in order to respond to varying requirements of end-users. It divides the complex problem of survivable routing in IP-MPLS/WDM networks into two subproblems, one for each network layer, which enables finding the...
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Customized crossover in evolutionary sets of safe ship trajectories
PublicationThe paper presents selected aspects of evolutionary sets of safe ship trajectories-a method which applies evolutionary algorithms and some of the assumptions of game theory to solving ship encounter situations. For given positions and motion parameters of the ships, the method finds a near optimal set of safe trajectories of all ships involved in an encounter. The method works in real time and the solutions must be returned within...
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The finite-difference simulation of x-rays propagation through a system of lenses
PublicationThe propagation of X-ray waves through an optical system consisting of 33 aluminum X-ray refractive lenses is considered. For solving the problem, a finite-difference method is suggested and investigated. It is shown that very small steps of the difference grid are necessary for reliable computation of propagation of X-ray waves through the system of lenses. It is shown that the wave phase is a function very quickly increasing...
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The Doppler effect in a bistatic system for determining the position of moving targets
PublicationThe article presents the theoretical analysis and the results of numerical calculations of the Doppler effect it occurs in a system designed to determine the position and speed of a moving target. The transmitter is the source of the signal and it emits a sinusoidal, acoustic and continuous wave. Signal reflected off a moving target is received by four hydrophones. Based on the signals, four Doppler shifts are determined and inserted...
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Influence of terpenes on indoor air quality
PublicationThe aim of this study was to investigate air quality in hairdresser salons, focusing on terpenes determination. Terpenes are known reactive volatile organic compounds that contribute to secondary organic aerosol formation. Those compounds are frequently found in cosmetic products as fragrance agents. Hairdresser salons are special kind of environment, where secondary organic aerosol concentration may be elevated. One hairdresser...
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Jaroslaw Spychala dr
PeopleOprócz bardzo dobrego wykształcenia osoba posiada również wieloletnie doświadczenie zawodowe, które jest poświadczeniem tego, że potrafi wykorzystać swoją wiedzę teoretyczną w praktycznych działaniach. Doświadczenie zawodowe jest bardzo bogate i rozbudowane. Ze względu na nabyte całkiem nowe umiejętności zwiększa się atrakcyjność doświadczonego pracownika. Są to między innymi kreatywne myślenie, zorientowanie na cel, odporność...
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Engineering Analysis with ANSYS Software Second Edition
PublicationThe best way to learn complex systems is by means of hands-on experience. With an innovative and clear tutorial based approach, this powerful book provides a comprehensive introduction to the fundamental areas of engineering analysis needed on research or commercial engineering projects. With its detailed step-by-step explanations and sample problems, this book will develop the reader's understanding of FEA and their ability to...
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Waves Along Fractal Coastlines: From Fractal Arithmetic to Wave Equations
PublicationBeginning with addition and multiplication intrinsic to a Koch-type curve, we formulate and solve wave equation describing wave propagation along a fractal coastline. As opposed to examples known from the literature, we do not replace the fractal by the continuum in which it is embedded. This seems to be the first example of a truly intrinsic description of wave propagation along a fractal curve. The theory is relativistically...
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Geometrically nonlinear analysis of shells - Benchmark problems for Autocad Robot Analysis Professional
PublicationThe aim of this work is to verify the suitability of commercial engineering software for geometrically nonlinear analysis of shells. This paper deals with the static, geometrically nonlinear analysis of shells made of an isotropic material. The Finite Element Method (FEM) is chosen to solve the problem. The results of the commercial software Autocad Robot Structural Analysis Professional (ARSAP) are compared with the litera-ture...
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A graph coloring approach to scheduling of multiprocessor tasks on dedicated machines with availability constraints
PublicationWe address a generalization of the classical 1- and 2-processor unit execution time scheduling problem on dedicated machines. In our chromatic model of scheduling machines have non-simultaneous availability times and tasks have arbitrary release times and due dates. Also, the versatility of our approach makes it possible to generalize all known classical criteria of optimality. Under these stipulations we show that the problem...
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Probabilistic sensitivity of the limit states of structures using Monte Carlom simulation
PublicationThe paper presents the concept of probabilistic sensitivity of structural limit states with respect to given design variables. A general idea is presented, illustrated by a simple case solved in an analytical way. More general approach is presented for the engineering structures, in this case a dedicated Monte Carlo simulation procedure is involved as part of the methodology. Illustration of the engineering case is done, by means...
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A note on polynomial algorithm for cost coloring of bipartite graphs with Δ ≤ 4
PublicationIn the note we consider vertex coloring of a graph in which each color has an associated cost which is incurred each time the color is assigned to a vertex. The cost of coloring is the sum of costs incurred at each vertex. We show that the minimum cost coloring problem for n-vertex bipartite graph of degree ∆≤4 can be solved in O(n^2) time. This extends Jansen’s result [K.Jansen,The optimum cost chromatic partition problem, in:...
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Balance errors in numerical solutions of shallow water equations
PublicationThe analysis of the conservative properties of the shallow water equations is presented in the paper. The work focuses on the consistency of numerical solution of these equations with the conservation laws of mass and momentum. The investigations involve two different conservative forms which are solved by an implicit box scheme. The theoretical analysis supported by numerical experiments is carried out for rectangular channel...
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Elimination of impulsive disturbances from stereo audio recordings
PublicationThis paper presents a new approach to elimination of impulsive disturbances from stereo audio recordings. The proposed solution is based on vector autoregressive modeling of audio signals. On-line tracking of signal model parameters is performed using the stability-preserving Whittle-Wiggins-Robinson algorithm with exponential data weighting. Detection of noise pulses and model-based interpolation of the irrevocably distorted samples...
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Scheduling of unit-length jobs with bipartite incompatibility graphs on four uniform machines
PublicationThe problem of scheduling n identical jobs on 4 uniform machines with speeds s1>=s2>=s3>=s4 is considered.The aim is to find a schedule with minimum possible length. We assume that jobs are subject to mutual exclusion constraints modeled by a bipartite incompatibility graph of degree delta. We show that the general problem is NP-hard even if s1=s2=s3. If, however, delta<5 and s1>12s2 s2=s3=s4, then the problem can be solved to...
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Modeling DAC Application Execution Time
PublicationAn application written in the Divide And Conquer paradigm is more difficult to model than SPMD application because of complex algorithm, causing use of many coefficients in a computational complexity function. Processors are divided into various layers, each layer contains different number of processors. Data packets processed in different layers and transferred between layers have different length. Moreover first layer processors use...
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Group project NT2-eng. 2024
e-Learning CoursesCourse for 2nd degree Students of Nanotechnology, sem. 3. The aim of the course is to prepare students for teamwork by implementing a project involving the analysis of the problem by the team, presenting a proposal to solve the problem, conducting research/tests and preparing a report.
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Group project (NT2-eng. sem.3) - 2023
e-Learning CoursesCourse for 2nd degree Students of Nanotechnology, sem. 3. The aim of the course is to prepare students for teamwork by implementing a project involving the analysis of the problem by the team, presenting a proposal to solve the problem, conducting research/tests and preparing a report.
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Real-time simulation in non real-time environment
PublicationSimulation in real-time is a very useful tool because of didactical and practical benefits. Very important benefit of real-time simulation is a fact that operator’s decision can be taken into account in the same time scale as the real system would work. This enables construction of simulators, and opportunity to test control algorithms in Hardware in The Loop scheme using target industrial equipment. Professional real-time environments...
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Silicon’s Influence on Polyphenol and Flavonoid Profiles in Pea (Pisum sativum L.) under Cadmium Exposure in Hydroponics: A Study of Metabolomics, Extraction Efficacy, and Antimicrobial Properties of Extracts
PublicationThe current study aimed to investigate the impact of silicon (Si) supplementation in the form of Na2SiO3 on the metabolome of peas under normal conditions and following exposure to cadmium (Cd) stress. Si is known for its ability to enhance stress tolerance in various plant species, including the mitigation of heavy metal toxicity. Cd, a significant contaminant, poses risks to...
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Role of Silicon in Counteracting Cadmium Stress in Pea Plants (Pisum sativum L.): Insights Into Cadmium Binding Mechanisms and Pectin Methylesterase Activity
PublicationPurpose: The aim of this study was to investigate the role of silicon (Si) in counteracting a cadmium (Cd) stress to pea plants (Pisum sativum L.) and to identify the mechanism by which Cd is bound within pea roots. Methods: These goals were achieved through (i) a histochemical study of Cd localization in pea roots, (ii) spectrophotometric determination of pectin content and the activity...
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Microporous Polyurethane Thin Layer as a Promising Scaffold for Tissue Engineering
PublicationThe literature describes that the most efficient cell penetration takes place at 200–500 µm depth of the scaffold. Many different scaffold fabrication techniques were described to reach these guidelines. One such technique is solvent casting particulate leaching (SC/PL). The main advantage of this technique is its simplicity and cost efficiency, while its main disadvantage is the scaffold thickness, which is usually not less than...
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Polyurethane porous scaffolds (PPS) for soft tissue regenerative medicine applications
PublicationTissue engineering requires suitable polymeric scaffolds, which act as a physical support for regenerated tissue. A promising candidate might be polyurethane (PUR) scaffold, due to the ease of the PUR properties design, which can be adjusted directly to the intended purpose. In this study, we report a successful fabrication of porous polyurethane scaffolds (PPS) using solvent casting/particulate leaching technique combined with...
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Microwave radiation in the synthesis of urethane prepolymers
PublicationThis paper describes the use of microwave radiation in the synthesis of urethane prepolymers in bulk (without solvent). The prepolymers were synthesized using 1,6-hexamethylene diisocyanate (HDI) and poly (ε-caprolactone) diol (PCL) at a molar ratio of 4:1. The reaction was carried out without a catalyst in the reactor with a conventional heating system (oil bath) or in the microwave reactor (MW Reactor NOVA 09) at temperatures...
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Synthesis, structural characterization and reactivity of new trisubstituted N1-acylamidrazones: solid state and solution studies
PublicationA series of new linear trisubstituted N1-acylamidrazones have been investigated using a variety of analytical techniques and theoretical calculations to check the influence of the type of N1-acyl substituent on the resonance forms and conformational behavior in the solid state and in solution. The 1D- and 2D-NMR experiments, supported by computational studies, revealed that in solution all amidrazones exhibit conformational syn/anti...
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Stabilities of bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, and their derivatives under controlled conditions analyzed using liquid chromatography coupled with tandem mass spectrometry
PublicationBisphenol A diglycidyl ether (BADGE), bisphenol F diglycydyl ether (BFDGE), and their related compounds are widely used as precursors in production of epoxy resins. The high reactivity of these compounds makes the development of analytical methodologies that ensure appropriate metrological accuracy crucial. Consequently, we aimed to determine whether and to what extent the composition of the solution and storage conditions affect...
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Geochemical fractionation of organic matter in the Jurassic-Cretaceous Vaca Muerta shale, Argentina
PublicationSeveral studies have indicated the presence of more than one generation of bitumen that could be isolated from rocks through sequential extraction or after demineralization or both. Nabbefeld et al. (2010a) and Holman et al. (2012, 2014) termed bitumen obtained after solvent extraction from the undigested rock as “Bitumen I" and that obtained by extraction after demineralization of rock as “Bitumen II.” The occurrence of different...
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Comparison of classical and modern approach of determination of highly polar compounds by High Performance Liquid Chromatography coupled with Tandem Mass Spectrometry
PublicationAbstract: Sugars and sugar alcohols are known as highly polar compounds. Four analytes were taken into consideration for comparison of classical and modern approach of separation of highly polar substances. Mannitol was chosen as an example of simple sugar alcohol, sucrose and lactulose as examples of disaccharides and structural isomers, raffinose as an example of complex trisaccharide. Raffinose was also used as internal standard...
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Determination of polybrominated diphenyl ethers in house dust using standard addition method and gas chromatography with electron capture and mass spectrometric detection
PublicationMonitoring of the environmental fate of polybrominated diphenyl ethers (PBDEs) involves determination of their concentration in air, airborne particles and settled dust. This requires the implementation of appropriate analytical tools like measuring instruments, reference materials and analytical procedures. In this study an analytical procedure was developed for determining PBDEs in samples with a complex matrix composition. The...
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Chitosan-Based Membranes as Gentamicin Carriers for Biomedical Applications — Influence of Chitosan Molecular Weight
PublicationOver the past decade, much attention has been paid to chitosan as a potential drug carrier because of its non-toxicity, biocompatibility, biodegradability and antibacterial properties. The effect of various chitosan characteristics on its ability to carry different antibiotics is discussed in the literature. In this work, we evaluated the influence of the different molecular weights of this polymer on its potential as an antibacterial...
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Parallel tabu search for graph coloring problem
PublicationTabu search is a simple, yet powerful meta-heuristic based on local search that has been often used to solve combinatorial optimization problems like the graph coloring problem. This paper presents current taxonomy of patallel tabu search algorithms and compares three parallelization techniques applied to Tabucol, a sequential TS algorithm for graph coloring. The experimental results are based on graphs available from the DIMACS...
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Modal Reduction and Analysis of Gyroscopic Systems
PublicationThe paper introduces the method of the modal reduction of systems that experience the Coriolis acceleration or gyroscopic effect component. In such cases corresponding system equations are non-self-adjoined. To solve the problem modal reduced model is built up for the system without Coriolis acceleration or gyroscopic effect terms. These phenomena are included by application of any lumping technique. Hence, the final reduced model...
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ORF Approximation in Numerical Analysis of Fractional Point Kinetics and Heat Exchange Model of Nuclear Reactor
PublicationThis paper presents results concerning numerical solutions of the fractional point kinetics (FPK) and heat exchange (HE) model for a nuclear reactor. The model consists of a nonlinear system of fractional and ordinary differential equations. Two methods to solve the model are compared. The first one applies Oustaloup Recursive Filter (ORF) and the second one applies Refined Oustaloup Recursive Filter (RORF). Simulation tests have...
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ORF Approximation in Numerical Analysis of Fractional Point Kinetics and Heat Exchange Model of Nuclear Reactor
PublicationThis paper presents results concerning numerical solutions of the fractional point kinetics (FPK) and heat exchange (HE) model for a nuclear reactor. The model consists of a nonlinear system of fractional and ordinary differential equations. Two methods to solve the model are compared. The first one applies Oustaloup Recursive Filter (ORF) and the second one applies Refined Oustaloup Recursive Filter (RORF). Simulation tests have...
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An interval estimator for chlorine monitoring in drinking water distribution systems under uncertain system dynamics, inputs and chlorine concentration measurement errors
PublicationThe design of an interval observer for estimation of unmeasured state variables with application to drinking water distribution systems is described. In particular, the design process of such an observer is considered for estimation of the water quality described by the concentration of free chlorine. The interval observer is derived to produce the robust interval bounds on the estimated water quality state variables. The stability...
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Joints Of Steel Sandwich Structures
PublicationSteel sandwich structures are perceived as alternatives to single-skin welded structures in the shipbuilding industry due its advantages like significant reduction of mass in relation to typical single skin structure. However, beside problems with their strength properties itself, applications in real structures requires of solving the problem of joining, both for connection sandwich to sandwich as well as sandwiches to single-shell...
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Selected manufacturing difficulties encountered during setup of machining on cnc multi-axis linear automatic lathe and on cnc multi-spindle turning centers
PublicationThe article presents the observed manufacturing technology implementation difficulties in workshop practice, resulting from the construction and principles of operation on the DMG’s SPRINT 32/5 CNC linear automatic lathe and on the Mazak’s HQR 150 MSY and QTN 200 MS CNC turn - mill centers, and discusses possible rules for solving the production problems encountered. The article also discusses the principles of dividing the machining...
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Task Scheduling – Review of Algorithms and Analysis of Potential Use in a Biological Wastewater Treatment Plant
PublicationThe idea of task scheduling is to increase the efficiency of a system by minimising wasted time, evenly loading machines, or maximising the throughput of machines. Moreover, the use of appropriate scheduling algorithms often leads to a reduction in the energy costs of the process. Task scheduling problems are found in a variety of industrial areas, and their scale changes significantly depending on the problem. This review shows...
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Valuation of architectural heritage by multicultural student groups
PublicationIn this article, the author addresses the education of architecture students in the field of architectural history and the determination of the value of architectural objects. Important changes at present are underway concerning this. Both the role of architectural history in architectural education and content in architectural history curricula is changing. The need for re-evaluation...
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Semi-definite programming and quantum information
PublicationThis paper presents a comprehensive exploration of semi-definite programming (SDP) techniques within the context of quantum information. It examines the mathematical foundations of convex optimization, duality, and SDP formulations, providing a solid theoretical framework for addressing optimization challenges in quantum systems. By leveraging these tools, researchers and practitioners can characterize classical and quantum correlations,...
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Practical Approach to IP Scheduled Throughput Measurements in Dual Connectivity Systems
PublicationIP scheduled throughput defined according to 3GPP TS 36.314 reflects user throughput regardless of traffic characteristics, and therefore has become one of the most important indicators for monitoring Quality of Service (QoS) of the end user in Evolved Universal Terrestrial Radio Access Network (E-UTRAN). However, networks built on a distributed architecture make the above definition impossible to be applied directly due to the...