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Zn(II) and Cd(II) coordination polymers with tri-tert-butoxysilanethiol and bipyridines. Synthesis, crystal structure and spectroscopy
PublicationTrzy nowe silanotiolany cynku(II) I kadmu(II) [Zn{SSi(OtBu)3}2(μ-bpea) •CH3CN]n 1, [Cd{SSi(OtBu)3}2(μ -bpea) •2CHCl3]n 2 oraz [Cd{SSi(OtBu)3}2(μ -bpey)•C7H8]n 3 otrzymane z użyciem pochodnych bipirydylu [bpea = 1,2-bis(4-pyridyl)etan and bpey = 1,2-bis(4-pyridyl)etylen] zostały zsyntetyzowane i strutkualnie scharakteryzowane przy użyciu rentgenografii strukturalnej XRD. Ich budowa krystaliczna została dodatkowo potwierdzona przy...
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Luminescent properties of Ln3+ doped tellurite glasses containing AlF3
PublicationThe low-phonon energy tellurite glasses TeO2-BaO-Bi2O3 and TeO2-BaO-Bi2O3-AlF3 triply doped with Eu3+, Tb3+, Tm3+ ions in two different molar ratios were synthesized using melt-quenching technique. Their structure and luminescence properties were widely investigated by X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR) and Photoluminescence Spectroscopy (PL). The luminescence...
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Thickness and structure change of titanium (IV) oxide thin films synthesized by the sol–gel spin coating method
PublicationTitanium dioxide is a well-known material in nanotechnology, while it provides new opportunities due to its interesting properties, for example, as a semiconductor with a quite significant forbidden band gap energy of 3.2 eV. In this study, thin films of titanium dioxide (TiO2) were synthesized in amorphous and crystallographic systems using the sol–gel process. Atomic Force Microscopy (AFM), Raman spectroscopy and X-ray diffraction...
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Metal enhanced fluorescence of flavin mononucleotide using new plasmonic platform
PublicationNew plasmonic platform was successfully obtained to investigate the increase of fluorescence intensity of a fluorophore in the presence of silver nanoparticles. A flavin mononucleotide, was selected by us as a fluorophore for this study as a very important biological compound playing a key role in many biochemical process. Plasmonic platforms were characterized by means of luminescence spectroscopy. Flavin mononucleotide deposited...
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Excitation energy transfer in partly ordered polymer films differing in donor and acceptor transition moments orientation
PublicationBased on spectroscopic measurements selected properties of nonradiative Förster energy transport are studied in uniaxially stretched polyvinyl alcohol thin films for three systems differing in donor and acceptor transition moments orientation relative to the axis of stretching. In particular, donor – acceptor emission anisotropy spectra yield completely different regularities for these systems in uniaxially stretched films, whereas...
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Determination of refractive index dispersion using fiber-optic low-coherence Fabry–Perot interferometer: implementation and validation
PublicationWe present the implementation and validation of low-coherence Fabry–Perot interferometer for refractive index dispersion measurements of liquids. A measurement system has been created with the use of four superluminescent diodes with different optical parameters, a fiber-optic coupler and an optical spectrum analyzer. The Fabry–Perot interferometer cavity has been formed by the fiber-optic end and mirror surfaces mounted on a micromechanical...
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Aggregation of Rhodamine 6G in titanium dioxide nanolayers and bulk xerogels
PublicationNanolayers and bulk xerogels of Rhodamine 6G (Rh6G) in titanium dioxide (Rh6G/TiO2) were prepared using the sol–gel method. The spectroscopic and structural properties of these two types of hybrid matrices were studied as a function of dye concentration. In both cases absorption, fluorescence and time resolved emission spectra show the formation of fluorescent aggregates. The observed stronger changes in characteristics of bulk...
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Impact of the inclination angle of the condenser with refrigerant R410A on heat transfer coefficient – experimental study
PublicationIn the paper the authors present results of a laboratory test of the condenser with refrigerant R410A. The effect of the inclination of this condenser on the heat transfer coefficient value has been considered. The test has proved that there is an optimal inclination angle of the condenser which gives maximal value of this coefficient.
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The Impact of Direct Normal Irradiation on the Solar Tower Power Plant Performance based on Real and Satellite Data: Analysis on Algerian Regions
PublicationThe present paper presents a deep study on the possibility of implementing Concentrated Solar Power (CSP) plants in Algeria for the production of the electrical energy. Indeed, this paper focusses mainly on the main parameters, which can have an important impact on the choice of the location, the dimension and the available thermal energy storage system. In this study, three main parameters are investigate...
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Optimization of thermal backfill configurations for desired high-voltage power cables ampacity
PublicationThe ampacity of high-voltage power cables depends, among others, on their core cross-sectional area as well as thermal resistivity of the thermal backfill surrounding the cables. The cross-sectional area of the power cables’ core is selected according to the expected power to be transferred via the cable system. Usually, the higher the power transfer required, the higher the cross-sectional area of the core. However, the cost of...
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Preference-based evolutionary multi-objective optimization in ship weather routing
PublicationIn evolutionary multi-objective optimization (EMO) the aim is to find a set of Pareto-optimal solutions. Such approach may be applied to multiple real-life problems, including weather routing (WR) of ships. The route should be optimal in terms of passage time, fuel consumption and safety of crew and cargo while taking into account dynamically changing weather conditions. Additionally it must not violate any navigational constraints...
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Mixed integer nonlinear optimization of biological processes in wastewater sequencing batch reactor
PublicationWastewater treatment plays a key role for humanity. The waste entering lakes, rivers, and seas deteriorates daily quality of life. Therefore, it is very important to improve the efficiency of wastewater treatment. From a control point of view, a biological wastewater treatment plant is a complex, non-linear, multidimensional, hybrid control system. The paper presents the design of the optimizing hierarchical control system applied...
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Liquid chromatography techniques for separation of flavonoids from Droseraceae
PublicationFlavonoids which are presented in insectivorous plants of the Droseraceae family have wide range of advantageous properties i.e. an antioxidant, anti-inflammatory and antimicrobial activities, antitumor activity was reported as well.The purpose of the research was to develop the most favourable conditions for liquid chromatographic separation and identification of myricetin and quercetin in extracts of insectivorous plants. In...
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Multi-objective design optimization of antenna structures using sequential domain patching with automated patch size deter-mination
PublicationIn this paper, a simple yet efficient and reliable technique for fully automated multi-objective design optimization of antenna structures using sequential domain patching (SDP) is discussed. The optimization procedure according to SDP is a two-step process: (i) obtaining the initial set of Pareto-optimal designs representing the best possible trade-offs between considered conflicting objectives, and (ii) Pareto set refinement...
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Are Pair Trading Strategies Profitable During COVID-19 Period?
PublicationPair trading strategy is a well-known profitable strategy in stock, forex, and commodity markets. As most of the world stock markets declined during COVID-19 period, therefore this study is going to observe whether this strategy is still profitable after COVID-19 pandemic. One of the powerful algorithms of DBSCAN under the umbrella of unsupervised machine learning is applied and three clusters were formed by using market and accounting...
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Ionogel fibres of bis(trifluoromethanesulfonyl)imide anion-based ionic liquids for the headspace solid-phase microextraction of chlorinated organic pollutants
PublicationIonogels, a family of hybrid materials in which ionic liquids (ILs) are confined in a sol–gel network, are receiving much attention in a variety of scientific and technological fields. In this work, ionogels derived from three different ILs based on the anion bis(trifluoromethanesulfonyl)imide (TFSI), namely 1-butyl- 3-methylpyridinium bis(trifluoromethanesulfonyl)imide ([C4C1Py][TFSI]), 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide...
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Application of titanium dioxide thin films in fiber optic sensors
PublicationThe advance in the nanotechnology and fabrication of micro- and nanostructures has significant impact on development of new optical sensors. Presented study focuses on the applications of the titanium dioxide (TiO2) thin films in fiber optic sensors. The concept of a sensing fiber optic interferometer integrating TiO2 thin film is presented. The cavity of this interferometer is delimited by a 80 nm film fabricated on the end-face...
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Analysis of Properties of an Active Linear Gesture Sensor
PublicationBasic gesture sensors can play a significant role as input units in mobile smart devices. However, they have to handle a wide variety of gestures while preserving the advantages of basic sensors. In this paper a user-determined approach to the design of a sparse optical gesture sensor is proposed. The statistical research on a study group of individuals includes the measurement of user-related parameters like the speed of a performed...
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Magnetic field mapping along a NV-rich nanodiamond-doped fiber
PublicationIntegration of NV−-rich diamond with optical fibers enables guiding quantum information on the spin state of the NV− color center. Diamond-functionalized optical fiber sensors have been demonstrated with impressive sub-nanotesla magnetic field sensitivities over localized magnetic field sources, but their potential for distributed sensing remains unexplored. The volumetric incorporation of diamonds into the optical fiber core allows...
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High Efficiency Dual-Active-Bridge Converter with Triple-Phase-Shift Control for Battery Charger of Electric Vehicles
PublicationAn optimal modulation scheme with triple-phase-shift (TPS) control could increase the efficiency in the entire load range for a dual-active-bridge (DAB) converter under wide output voltage range conditions. Therefore, this study proposes a convergent approach to TPS mode selection, coupled with an optimal modulation scheme, ensuring the circuit’s efficiency over the entire range in the realm of a high-power and high-efficiency...
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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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Rapid antenna design optimization using shape-preserving response prediction
PublicationAn approach to rapid optimization of antennas using the shape-preserving response-prediction (SPRP) technique and coarsediscretization electromagnetic (EM) simulations (as a low-fidelity model) is presented. SPRP allows us to estimate the response of the high-fidelity EM antenna model, e.g., its reflection coefficient versus frequency, using the properly selected set of so-called characteristic points of the low-fidelity model...
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Equitable colorings of some variation of corona products of cubic graphs
PublicationThe problem of determining the value of equitable chromatic number for multicoronas of cubic graphs is studied. We provide some polynomially solvable cases of cubical multicoronas and give simple linear time algorithms for equitable coloring of such graphs which use almost optimal number of colors in the remaining cases.
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Investigation of electrocatalytic gas sensor properties in presence of chlorine
PublicationIn this paper performance of an electrocatalytic sensor in presence of chlorine is investigated. Presented studies concern sensor prepared in ceramic technology based on NASICON as a solid electrolyte with two round shaped platinum electrodes. Measurements in different temperatures have been performed in order to determine optimal sensor working temperature.
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THE USE OF GREEN LOGISTICS ELEMENTS DURING THE CONSTRUCTION OF OFFSHORE VESSELS
PublicationThe article is aimed at the presentation referring to the use of green logistics elements during the construction of the offshore vessels in the following aspects: collection, removal and utilisation of any waste that is harmful for natural environment, elimination of the negative impact that such waste can have on natural environment and the search for the optimal solutions as regards these aspects.
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Introduction to the ONDM 2022 special issue
PublicationThis JOCN special issue contains extended versions of selected papers presented at the 26th International Conference on Optical Network Design and Modeling (ONDM 2022), which took place 16–19 May 2022 at Warsaw University of Technology, Warsaw, Poland. The topics covered by the papers represent trends in optical networking research: application of machine learning to network management, cross-layer network performance optimization,...
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Selecting cost-effective risk control option for advanced maritime operations; Integration of STPA-BN-Influence diagram
PublicationAdvanced maritime operations, such as remote pilotage, are vulnerable to new emergent risks due to increased system complexity and a multitude of interactions. Thus, maritime researchers this decade have combined Systems-Theoretic Process Analysis (STPA) and Bayesian Network (BN) to effectively manage these risks. Although these methods are effective in identifying hazards and analyzing risk levels, none of the STPA-BN studies...
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Structure and the space vector modulation for a medium-voltage power-electronic-transformer based on two seven-level cascade H-bridge inverters
PublicationThis study presents the structure and the space vector pulse-width modulation (SVPWM) for power electronic transformer (PET) based on two seven-level cascade H-bridge (CHB) inverters. The DC links of CHB inverters are coupled with nine dual-active bridge (DAB) converters with medium-frequency transformers. The DC-link voltages are equalised with two methods – through the control of DAB voltages...
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Approximation Strategies for Generalized Binary Search in Weighted Trees
PublicationWe consider the following generalization of the binary search problem. A search strategy is required to locate an unknown target node t in a given tree T. Upon querying a node v of the tree, the strategy receives as a reply an indication of the connected component of T\{v} containing the target t. The cost of querying each node is given by a known non-negative weight function, and the considered objective is to minimize the total...
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ANALYSIS AND OPTIMIZATION OF ELECTRIC VEHICLE CHARGING PROCESSES IN TRANSACTIVE ENERGY SYSTEMS
PublicationThe implementation of smart charging of electric vehicles allows operators of local power networks and electricity suppliers to implement new business models for the interaction of electric vehicles with the network. In addition to the optimal selection of Microgrid capacities when charging electric vehicles, it is also important to use different charging methods. To satisfy the interests of all participants of local systems from...
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How thermal stability of ionic liquids leads to more efficient TiO2-based nanophotocatalysts: Theoretical and experimental studies
PublicationIonic liquids (ILs) containing distinct nitrogen-bearing organic cations (pyridinium, pyrrolidinium, imidazolium, ammonium, morpholinium) were first used for the preparation of 23 IL-TiO2 types of composites by ionic liquid assisted solvothermal synthesis. These 23 optimal ILs structures (i.e. compounds exhibiting an optimal combination of specific properties, functionality, and safety) for synthesis and experimental validation...
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Functional fluorine-doped tin oxide coating for opto-electrochemical label-free biosensors
PublicationSensors operating in multiple domains, such as optical and electrochemical, offer properties making biosensing more effective than those working in a single domain. To combine such domains in one sensing device, materials offering a certain set of properties are required. Fluorine-doped tin oxide (FTO) thin film is discussed in this work as functional optically for guiding lossy modes and simultaneously electrochemically, i.e....
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Application of fiber optic sensors using Machine Learning algorithms for temperature measurement of lithium-ion batteries
PublicationOptical fiber sensorsusing low-coherence interferometry require processing ofthe output spectrum or interferogramto quickly and accurately determine the instantaneous value of the measured quantity, such as temperature.Methods based on machine learning are a good candidate for this application. The application of four such methods in an optical fiber temperature sensoris demonstrated.Using aZnO-coated...
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Measurement of complex refractive index of human blood by low-coherence interferometry
PublicationIn this article, the usefulness of the optical technique for measurements of blood complex refractive index has been examined. Measurement of optical properties of human blood is difficult to perform because of its nonuniform nature. However, results of my investigation have shown the usefulness of low-coherencei nterferometry for measurement complex refractive index of human blood. Furthermore, mathematical analysis of spectrum...
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Genetic Positioning of Fire Stations Utilizing Grid-computing Platform
PublicationA chapter presents a model for determining near-optimal locations of fire stations based on topography of a given area and location of forests, rivers, lakes and other elements of the site. The model is based on principals of genetic algorithms and utilizes the power of the grid to distribute and execute in parallel most performance-demanding computations involved in the algorithm.
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A Stabilized Complex LOBPCG Eigensolver for the Analysis of Moderately Lossy EM Structures
PublicationThis letter proposes a stabilized locally optimal block preconditioned conjugate gradient method for computing selected eigenvalues for complex symmetric generalized non-Hermitian eigenproblems. Effectiveness of the presented approach is demonstrated for a moderately lossy dual-mode dielectric resonator, modeled using finite-element method with higher order elements
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Rapid multi-objective design of integrated on-chip inductors by means of Pareto front exploration and design extrapolation
PublicationIdentification of the best trade-offs between conflicting design objectives allows for making educated design decisions as well as assessing suitability of a given component or circuit for a specific application. In case of inductors, the typical objectives include maximization of the quality factor and minimization of the layout area, as well as maintaining a required inductance at a given operating frequency. This work demonstrates...
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Evaluation of Three Peptide Immobilization Techniques on a QCM Surface Related to Acetaldehyde Responses in the Gas Phase
PublicationThe quartz-crystal microbalance is a sensitive and universal tool for measuring concentrations of various gases in the air. Biochemical functionalization of the QCM electrode allows a label-free detection of specific molecular interactions with high sensitivity and specificity. In addition, it enables a real-time determination of its kinetic rates and affinity constants. This makes QCM a versatile bioanalytical screening tool for...
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Time versus space trade-offs for randezvous in trees
PublicationTwo identical (anonymous) mobile agents start from arbitrary nodes of an unknown tree and have to meet at some node. Agents move in synchronous rounds: in each round an agent can either stay at the current node or move to one of its neighbors. We consider deterministic algorithms for this rendezvous task. The main result of this paper is a tight trade-off between the optimal time of completing rendezvous and the size of memory...
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On structural physical approximations and entanglement breaking maps
PublicationVery recently, a conjecture saying that the so-called structural physical approximations (SPAs) to optimal positive maps (optimal entanglement witnesses) give entanglement breaking (EB) maps (separable states) has been posed (Korbicz et al 2008 Phys. Rev. A 78 062105). The main purpose of this contribution is to explore this subject. First, we extend the set of entanglement witnesses supporting the conjecture. Then, we ask whether...
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Pareto Ranking Bisection Algorithm for EM-Driven Multi-Objective Design of Antennas in Highly-Dimensional Parameter Spaces
PublicationA deterministic technique for fast surrogate-assisted multi-objective design optimization of antennas in highly-dimensional parameters spaces has been discussed. In this two-stage approach, the initial approximation of the Pareto set representing the best compromise between conflicting objectives is obtained using a bisection algorithm which finds new Pareto-optimal designs by dividing the line segments interconnecting previously...
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Cooperation of mono- and bi-articular muscles: human lower limb
PublicationObjectives: The aim of this study was to create and analyze a Pareto-optimal problem that would describe cooperation between mono- and bi-articulate lower limb muscles in sagittal plane. Methods: Equations describing the problem were derived and analyzed, additional constrains were introduced and experimental verification based on gait video analysis was performed. Results: Uncertainty of Pareto-optimal solution is shown for the...
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Adaptive stochastic and hybrid nonlinear optimization algorithms for improving the effectiveness of the biological processes at WWTP
PublicationWastewater treatment plays an important factor in the modern world. Insufficient treatment may result in environmental pollution which can further lead to disasters and diseases. However, processes that take place inside wastewater treatment plants (WWTP) are highly complex in nature, therefore it is difficult to design an efficient, optimal control system. The problem regarding biochemical reactions inside Sequential Batch Reactor...
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Vibrational Quenching of Optically Pumped Carbon Dimer Anions
PublicationCareful control of quantum states is a gateway to research in many areas of science such as quantum information, quantum-controlled chemistry, and astrophysical processes. Precise optical control of molecular ions remains a challenge due to the scarcity of suitable level schemes, and direct laser cooling has not yet been achieved for either positive or negative molecular ions. Using a cryogenic wire trap, we show how the internal...
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Consequences of suboptimal design of Building Integrated Photovoltaic Installation – a case study for Gdansk, Poland
PublicationThe carried out analysis concerns 2 kWp building integrated photovoltaic installation (BIPV) at the Chemistry Faculty of Gdansk University of Technology. It was proven that the generated energy data for every month diverge significantly from the expected vales. It is corelated with suboptimal orientation of the installation itself, as well as with the tilt angle varying from optimal.
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Induced Sheath Voltages In 110 Kv Power Cables – Case Study
PublicationThe paper considers shock hazard due to induced sheath voltages in 110 kV power cables. Various configurations of the metallic sheaths bonding and earthing (single-point bonding, both-ends bonding, cross-bonding) are analysed. Taking into account shock hazard and ability of the system to power transfer an optimal configuration is proposed.
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The realization of ASON/GMPLS control plane
PublicationASON (Automatic Switched Optical Network) is a concept of optical network recommended in G.8080/Y.1304 by ITU-T. Control Plane of this network could be based on GMPLS (Generalized Multi-Protocol Label Switching) protocols like RSVP-TE, OSPF-TE, LMP. This solution is named ASON/GMPLS. In this chapter we present the control plane problems and proposes ASON/GMPLS network realization that are tested on testbed consists of three and...
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Application of Thin ZnO ALD Layers in Fiber-Optic Fabry-Pérot Sensing Interferometers
PublicationIn this paper we investigated the response of a fiber-optic Fabry-Pérot sensing interferometer with thin ZnO layers deposited on the end faces of the optical fibers forming the cavity. Standard telecommunication single-mode optical fiber (SMF-28) segments were used with the thin ZnO layers deposited by Atomic Layer Deposition (ALD). Measurements were performed with the interferometer illuminated by two broadband sources operating...
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A BRIEF REVIEW AND COMPARISON OF SELECTED EXPERIMENTAL METHODS FOR MEASURING NATURAL FREQUENCIES OF CIRCULAR SAW BLADES
PublicationDifferent methods for the empirical determination of the natural frequencies of circular saw blades are presented. Stationary methods, such as the harmonic and impulse tests, are discussed and the results of related comparison are given. The comparison of the methods revealed their degree of practical usefulness and their accuracy in determining natural frequencies. A combination of specific methods is proposed, which should allow...
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Skład i zawartość kwasów tłuszczowych w mleku kobiet z gdańska i okolic w różnych okresach laktacji = Fatty acid composition in breast milk of women from gdańsk and the surrounding district in the course of lactation
PublicationCelem pracy była ocena składu i zawartości kwasów tłuszczowych w tłuszczu mleka kobiet w różnych okresach laktacji, z uwzględnieniem składu KT pokarmu spożywanego przez matki. Do badań zakwalifikowano 80 położnic od których uzyskano próbki mleka w 2, 14, 30 i 90 dobie laktacji. Jednocześnie przeprowadzono badania ankietowe na podstawie których oszacowano zawartość poszczególny grup KT w dziennej racji pokarmowej matek. Skład i...