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Siedmiokryterialny miernik oceny niepotokowych procesów produkcyjnych
PublicationGrowing expectations of clients, who demand products adapted to their individual needs is inducing the development of batch processes. The author developed a model of batch processes rating based on the following criterions: • Economical criterion applies to evaluation of the productions’ cost levels connected with the process subjected to analysis and necessary investment funds. • Ecological criterion is about means of natural...
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Scattering of electrons by a 1,2-butadiene (C4H6) molecule: measurements and calculations
PublicationWe present the results of experimental and theoretical study on electron collisions with a 1,2-butadiene (H2C=C=CHCH3) molecule. Absolute grand-total cross sections (TCSs) were measured using a linear electron-transmission method for collision energies in the 0.5–300 eV range. Two distinct features in the TCS energy curve were detected: a narrow peak located at 2.3 eV and a broad enhancement centered around 9 eV. We attributed...
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Eco-friendly modification of bitumen: The effects of rubber wastes and castor oil on the microstructure, processability and properties
PublicationThe bitumen industry in the European Union is facing several difficulties, including rising demand, unstable oil supply, rising prices for synthetic polymer modifiers, and a focus on lowering carbon footprint. Bitumen modification with crumb rubber (CR) is one of the most promising solution to these challenges. However, CR-modified bitumen have poor processability and low storage stability. To overcome these flaws we are introducing...
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Chained machine learning model for predicting load capacity and ductility of steel fiber–reinforced concrete beams
PublicationOne of the main issues associated with steel fiber–reinforced concrete (SFRC) beams is the ability to anticipate their flexural response. With a comprehensive grid search, several stacked models (i.e., chained, parallel) consisting of various machine learning (ML) algorithms and artificial neural networks (ANNs) were developed to predict the flexural response of SFRC beams. The flexural performance of SFRC beams under bending was...
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Physical and mathematical modelling of implant-fascia system in order to improve laparoscopic repair of ventral hernia
PublicationThis paper describes an investigation of biomechanical behaviour of hernia repair, which is focused on the selection of safe linking of certain type of implant with fascia in laparoscopic operation. The strength of various fixations of the implant to the fascia is analysed. Methods: The research is based on experimental observations of operated hernia model behaviour during a dynamic impulse load corresponding to post-operative...
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ENERGY ANALYSIS OF THE PROPULSION SHAFT FATIGUE PROCESS IN A ROTATING MECHANICAL SYSTEM PART II IDENTIFICATION STUDIES – DEVELOPING THE FATIGUE DURABILITY MODEL OF A DRIVE SHAFT
PublicationThe article presents a continuation of research carried out concerning identification of energy consequences of mechanical fatigue within a propeller shaft in a rotating mechanical system, while working under conditions of the loss of the required alignment of shaft lines. Experimental research was carried out on a physical model reflecting a full-sized real object: i.e., the propulsion system of the ship. It is proven, by means...
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A new hyperbolic-polynomial higher-order elasticity theory for mechanics of thick FGM beams with imperfection in the material composition
PublicationA drawback to the material composition of thick functionally graded materials (FGM) beams is checked out in this research in conjunction with a novel hyperbolic‐polynomial higher‐order elasticity beam theory (HPET). The proposed beam model consists of a novel shape function for the distribution of shear stress deformation in the transverse coordinate. The beam theory also incorporates the stretching effect to present an indirect...
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Experimental and Numerical Investigation of Tensile and Flexural Behavior of Nanoclay Wood-Plastic Composite
PublicationIn this study, the effect of wood powder and nanoclay particle content on composites’ mechanical behavior made with polyethylene matrix has been investigated. The wood flour as a reinforcer made of wood powder was at levels of 30, 40, and 50 wt.%, and additional reinforcement with nanoclay at 0, 1, 3, and 5 wt.%. Furthermore, to make a composite matrix, high-density polyethylene was used at levels of 70, 60, and 50% by weight....
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A novel approach for processing CaAlSiON glass-ceramics by spark plasma sintering: Mechanical and electrical properties
PublicationLithium containing glassy materials can be used as solid electrolytes or electrode materials for lithium-ion batteries due to their high energy density. Conventional melt-quenched Ca11Al14Si16O49N10 glass powder containing 24 e/o N, doped with Li-ions (1, 3, and 6 wt. %) and sintered by spark plasma sintering technique (SPS) was studied. The benefits of using SPS to produce glass-ceramics are rapid heating rates compared to conventional...
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Electron collisions with X(CH3)4 molecules (X = C, Si, Ge)
PublicationAbsolute grand-total cross sections (TCSs) for electron scattering from tetramethylmethane [C(CH3)4], tetramethylsilane [Si(CH3)4], and tetramethylgermane [Ge(CH3)4] molecules have been measured at electron-impact energies extending from around 0.5 to 300 eV in the linear electron-transmission experiment. The measured TCS energy dependences show very pronounced broad enhancement, peaking near 5.5 eV for Si(CH3)4 and Ge(CH3)4 molecules...
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Experimental studies on the impact of changing the pipe material on the propagation of the pressure wave during water hammer
PublicationAim of the paper is to present the results studying the water hammer phenomenon in pipes made of different materials, and to show the impact of changing the type of material of the pipe on the velocity of the pressure wave during the transient flow in the pipes. In terms of research material and methods, pipes made of galvanized steel and high-density polyethylene were tested. Measurements were made using strain gauges with a high...
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Guided Wave Propagation in Detection of Partial Circumferential Debonding in Concrete Structures
PublicationThe following article presents results of investigating the damage detection in reinforced concrete beams with artificially introduced debonding between the rod and cover, using a non-destructive method based on elastic waves propagation. The primary aim of the research was to analyze the possible use of guided waves in partial circumferential debonding detection. Guided waves were excited and registered in reinforced concrete...
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Twitter jako narzędzie wspierające działania promocyjne szkół wyższych. Przykład Biblioteki Politechniki Gdańskiej
PublicationSerwis społecznościowy Twitter wydaje się być skutecznym narzędziem wspierającym nie tylko promowanie dorobku poszczególnych pracowników naukowych uczelni. Może być on także wykorzystywany do prowadzenia działań upowszechniających, promujących i popularyzujących wyniki działalności badawczo-rozwojowej, innowacyjnej i wynalazczej szkół wyższych w skali krajowej oraz międzynarodowej. Biblioteka akademicka może stanowić ważne wsparcie...
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Methods of Incomplete and Uncertain Knowledge Acquisition in the Knowledge Processing Environemnt
PublicationThe authors in this paper present a concept of the environment to acquire and process knowledge about information technology. This solution is part of a project of which the objective is to build a system for the evaluation of IT tools and methodologies. Knowledge within this domain is always either uncertain or incomplete. Therefore, the authors focused on designing a dedicated algorithm for its acquisition and processing. One...
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Crystal structure and low-energy Einstein mode in ErV2Al20 intermetallic cage compound
PublicationSingle crystals of a new ternary aluminide ErV2Al20 were grown using a self-flux method. The crystal structure was determined by powder X-ray diffraction measurements and Rietveld refinement, and physical properties were studied by means of electrical resistivity, magnetic susceptibility and specific heat measurements. These measurements reveal that ErV2Al20 is a Curie-Weiss paramagnet down to 1.95 K with an effective magnetic...
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An assessment of teeth quality of the mini gang saw blade
PublicationIn this work, the assessment of the effect of the operating time (90 min.) of the mini gang saw blades during sawing Scotch pine (Pinus sylvestris L.) samples upon changes of the saw blade teeth sharpness (bluntness), which was defined as an effective radius of the nose ρ , has been described. The research activities have been carried out on the Nikon Ti-S optical microscope equipped with the Nikon DS-30W camera allowing high-speed...
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Improved jamming resistance using electronically steerable parasitic antenna radiator
PublicationThis paper presents an idea of using an Electronically Steerable Parasitic Antenna Radiator (ESPAR) for jamming suppression in IEEE 802.11b networks. Jamming (intentional interference) attacks are known to be effective and easy to perform, which may impose connectivity problems in applications concerning Internet of Things (IoT). In our paper, theoretical considerations are presented and the results of experiments performed in...
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The distributed model predictive controller for the nuclear power plant turbo-generator set
PublicationTypically there are two main control loops with PI controllers operating at each turbo-generator set. In this paper a distributed model predictive controller DMPC, with local QDMC controllers for the turbine generator, is proposed instead of a typical PI controllers. The local QDMC controllers utilize step-response models for the controlled system components. These models parameters are determined based on the proposed black-box...
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A derivatisation agent selection guide
PublicationThe development of new tools for providing high quality information in a cost-effective and expeditious way is one of the main aims of analytical chemistry. Remarkably, the introduc- tion of the 12 principles of green chemistry paved the way forward for the development of analytical methodologies that are, ideally, inherently safe for the operator and the environ- ment, with the least possible consumption of energy and chemicals,...
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Selection of optimal location and rated power of capacitor banks in distribution network using genetic algorithm
PublicationIn this paper, the problem of placement and rated power of capacitor banks in the Distribution Network (DN) is considered. We try to suggest the best places for installing capacitor banks and define their reactive power. The considered formulation requires the optimization of the cost of two different objectives. Therefore the use of properly multiobjective heuristic optimization methods is desirable. To solve this problem we use...
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The concept of research on ecological, energy and reliability effects of modified marine fuel oils application to supply compression-ignition engines in real conditions
PublicationWithin the article, basic assumptions of the research project financed by Regional Fund for Environmental Protection and Water in Gdansk were described. The project concerns the experimental investigations carried out on laboratory compression-ignition engine in conditions of its supply with a non-standard marine fuel oil. Configuration and measuring capability of laboratory test bed presently being constructed were introduced....
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Akaike's final prediction error criterion revisited
PublicationWhen local identification of a nonstationary ARX system is carried out, two important decisions must be taken. First, one should decide upon the number of estimated parameters, i.e., on the model order. Second, one should choose the appropriate estimation bandwidth, related to the (effective) number of input-output data samples that will be used for identification/ tracking purposes. Failure to make the right decisions results...
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Quality assessment of ZnO-based varistors by 1/f noise
PublicationNoise has been used as a diagnostic tool of surge arrester varistor structures comprising of ZnO grains of various type and size. The physical and electrical properties of the measured samples have been described. In the experimental study, the applied measurement system and the results of noise measurements for the selected structures of varistors designed for the continuous working voltage 280 V, 440 V and 660 V have been presented....
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Interoperability Description of Web Services Based Application Servers
PublicationWeb services standards were designed to enable interoperability of heterogeneous application servers in the Service Oriented Architecture. Although the standards proved to be highly successful, there are still difficulties in effective services integration. The paper presents a methodology that enables description of application servers interoperability in order to improve the service integration process. The methodology proposes...
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Using argument structures to create a measurement plan
PublicationWhile planning an experiment the same question always arises: What are the goals of the experiment and which measurements are needed to demonstrate that the goals have been achieved? Deciding about the extent of raw data to be collected, the metrics to be constructed on those data and the interpretation of the metrics with respect to the assumed goals is by no means a trivial task. In this paper we show how a well known Gal-Question-Metrics...
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Examining Classifiers Applied to Static Hand Gesture Recognition in Novel Sound Mixing System
PublicationThe main objective of the chapter is to present the methodology and results of examining various classifiers (Nearest Neighbor-like algorithm with non-nested generalization (NNge), Naive Bayes, C4.5 (J48), Random Tree, Random Forests, Artificial Neural Networks (Multilayer Perceptron), Support Vector Machine (SVM) used for static gesture recognition. A problem of effective gesture recognition is outlined in the context of the system...
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Selected Methods for the Chemical Phosphorylation and Thiophosphorylation of Phenols
PublicationThis Focus Review gathers together a selection of methods for the chemical phosphorylation of phenols that employ three‐ and four‐coordinate phosphorus compounds. Phosphorylated scaffolds can exhibit enhanced properties compared to their non‐phosphorylated analogues, such as increased biological activity and increased/decreased solubility; as such, phosphorus compounds have gained more and more interest in organic and medicinal...
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Remote Estimation of Video-Based Vital Signs in Emotion Invocation Studies
PublicationAbstract— The goal of this study is to examine the influence of various imitated and video invoked emotions on the vital signs (respiratory and pulse rates). We also perform an analysis of the possibility to extract signals from sequences acquired with cost-effective cameras. The preliminary results show that the respiratory rate allows for better separation of some emotions than the pulse rate, yet this relation highly depends...
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Applicability of null-steering for spoofing mitigation in civilian GPS
PublicationCivilian GPS signals are currently used in many critical applications, such as precise timing for power grids and telecommunication networks. Spoofing may cause their improper functioning. It is a threat which emerges with the growing availability of GPS constellation simulators and other devices which may be used to perform such attack. Development of the effective countermeasures, covering detection and mitigation, is necessary...
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Advanced Ship Control Methods
PublicationThe chapter presents two main streams of research in vessel control at sea: dynamic positioning (DP) of the vessel and decision support in case of collision at sea. The control structure and basic requirements for the DP system are defined. Selected issues of automatic control of a dynamically positioned vessel are discussed. A review of advanced methods of controlling a DP ship is carried out, taking into account the tasks of...
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Degradation of Rhodamine dyes by Advanced Oxidation Processes (AOPs) – Focus on cavitation and photocatalysis - A critical review
PublicationThis review evaluates selected advanced oxidation processes (AOPs) - cavitation and photocatalysis - successfully used for wastewater treatment towards degradation of Rhodamine (Rh) dyes. Reactor configuration and impact of process parameters and oxidants addition (hydrogen peroxide, ozone, persulfates) on degradation effectiveness along with degradation mechanisms are discussed. Best technologies provide 100% degradation within...
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Mechanical, durability, depolluting and electrical properties of multifunctional mortars prepared with commercial or waste carbon-based fillers
PublicationCarbon-based fillers from industrial wastes and commercial ones were compared to improve the properties of lime-based mixes. As commercial fillers, graphene nanoplatelets and activated carbon were used, whereas as industrial wastes a char obtained by the gasification of biomasses and a used foundry sand were chosen. Carbon-based wastes were found to be a good cost-effective alternative to commercial carbon based fillers to increase...
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Promising Nanoparticle-Based Heat Transfer Fluids—Environmental and Techno-Economic Analysis Compared to Conventional Fluids
PublicationProviding optimal operating conditions is one of the major challenges for effective heating or cooling systems. Moreover, proper adjustment of the heat transfer fluid is also important from the viewpoint of the correct operation, maintenance, and cost efficiency of these systems. Therefore, in this paper, a detailed review of recent work on the subject of conventional and novel heat transfer fluid applications is presented. Particular...
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Polyurethane Nanocomposites Containing Reduced Graphene Oxide, FTIR, Raman, and XRD Studies
PublicationRecently, graphene and other graphene-based materials have become an essential part of composite science and technology. Their unique properties are not only restricted to graphene but also shared with derivative compounds like graphene oxide, reduced graphene oxide, functionalized graphene, and so forth. One of the most structurally important materials, graphene oxide (GO), is prepared by the oxidation of graphite. Though removal...
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Hard lessons learned: delivering usability in IT projects
PublicationEffective project management requires the development of a realistic plan which aims to ensure the success of the project and ultimately deliver a high quality product to customers. However, experience shows that the majority of software vendors managing projects suffer from numerous problems to provide usability in IT solutions and complete a project in a given time with success. In this paper we discuss, analyze and synthesize...
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A city and a wind farm. Landscape perspective
PublicationThe aim of the paper is to present the problems of the location of the wind farms in close neighbourhood to the historical cities, and the ways to minimize the potential landscape threats. The production of clean energy is obligatory in EU. In spite of how positive to the environment the wind energy production is, it may cause negative effects. The results of landscape studies of two towns in Poland prove that the location of such...
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PROJEKTOWANIE WIELOWYMIAROWEGO REGULATORA BACKSTEPPING W UKŁADZIE DYNAMICZNEGO POZYCJONOWANIA STATKU
PublicationW komercyjnych systemach dynamicznego pozycjonowania statku, pomimo znacznego wzrostu poziomu automatyzacji, wykorzystywane jest nadal sterowanie typu PID. Poprawę jakości procesu pozycjonowania może umożliwić wykorzystanie bardziej efektywnych algorytmów, oferujących zaawansowane nieliniowe techniki sterowania. W artykule przedstawiono zagadnienie projektowania regulatora pozycji i kursu dla układu dynamicznego pozycjonowania...
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2015. Motion analysis of a kitesurfer employing a vision-based measurement system
PublicationAbstract. Kitesurfing is a relatively new phenomenon with rising popularity worldwide – a recently developed extreme watersport considered a high-risk injury sport. It combines elements of several other sports, in particular, sailing, surfing, windsurfing, wakeboarding, and snowboarding. The main purpose of authors’ research in the present paper is to use a vision-based system for measuring a kitesurfer’s body movements in order...
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Effect of package type on selected parameters of nutritional quality of chill-stored white sauerkraut
PublicationBrassica vegetables, including white cabbage, both fresh and sour (Brassica oleracea L. var. capitata L.), contain a lot of valuable metabolites which are effective in chemoprevention of cancer as documented by numerous studies. This work investigates the effect of different packaging types; low density polyethylene (PE-LD) and metalized polyethylene terephthalate (PET met/PE) with polyethylene bags on selected quality parameters in...
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Corrosion Study of Ceria Protective Layer Deposited by Spray Pyrolysis on Steel Interconnects
PublicationSingle fuel cells and electrolysis cells are assembled into stacks using interconnects in order to increase power and gas production capacity. The most common choice for the interconnect material is stainless steel. It has good electrical and mechanical properties and is also cost effective. One of the problems when using steel is the formation of a thermally grown oxide scale during use which has a lower electrical conductivity...
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Deep neural networks approach to skin lesions classification — A comparative analysis
PublicationThe paper presents the results of research on the use of Deep Neural Networks (DNN) for automatic classification of the skin lesions. The authors have focused on the most effective kind of DNNs for image processing, namely Convolutional Neural Networks (CNN). In particular, three kinds of CNN were analyzed: VGG19, Residual Networks (ResNet) and the hybrid of VGG19 CNN with the Support Vector Machine (SVM). The research was carried...
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Accuracy of Differential Phase Delay Estimation for GPS Spoofing Detection
PublicationGPS spoofing is an attack based on transmission of false signals to target receivers, in order to force the computation of incorrect time, position or velocity information. It is a threat which is recently considered with continuously growing awareness. There is a need for effective way of GPS spoofing detection. Many groups of methods are proposed in the literature. Spatial processing methods are considered to be robust in a wide...
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THE ONLINE APPLICATION AND E-LEARNING IN THE COMPETENCE-BASED MANAGEMENT IN PUBLIC ADMINISTRATION ORGANIZATIONS
PublicationThe integration of effective management of work-related processes and utilization of human resources potential leads to the development of organization. The purpose of this paper was to examine how the principles of competences-based management can be introduced to enhance organization’s effectiveness in human resources management. A model of assessment and development of competences-based management, embracing an online application...
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Evolutionary sets of safe ship trajectories with speed reduction manoeuvres within traffic separation schemes
PublicationIn the previous paper the author presented the evolutionary ship trajectory planning method designed to support Traffic Separation Schemes (TSS). This time the extensions of this method are described which allow to combine evolutionary trajectory planning with speed reduction manoeuvres. On TSS regions with higher than usual density of traffic and smaller distances between ships, the course alterations alone are not always sufficient...
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Synthetic Principles Determining Local Organization of Copolyesters Prepared from Lactones and Macrolactones
PublicationA highly effective and facile technique for catalytic ring-opening copolymerization (cROP) of lactones viz. ε- caprolactone and ε-decalactone with ω-pentadecalactone is being described. The reactions were mediated by Zn- and Cabased tridentate Schiff base complexes and benzyl alcohol as initiator. The catalysts were successfully employed for the preparation of numerous block and random copolymers. To unravel the composition of...
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Virtual Engineering Factory: Creating Experience Base for Industry 4.0
PublicationABSTRACT In recent times, traditional manufacturing is upgrading and adopting Industry 4.0, which supports computerization of manufacturing by round-the-clock connection and communica- tion of engineering objects. Consequently, Decisional DNA- based knowledge representation of manufacturing objects, processes, and system is achieved by virtual engineering objects (VEO), virtual engineering processes (VEP), and virtual engineering...
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Integration of heterogeneous web services in exceptional situations
PublicationWeb services are intended to enable interoperability between heterogeneous distributed systems. Although the technology has been widely adopted and accepted, there are still differences between runtime platforms in exception structure and handling. This results in difficulties in effective handling of exceptions during Web services invocation. The paper presents a solution that enables coordinated exception handling between different...
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Degradation of Gel-Coat Layer in Glass/Polyester Laminate in Seawater Environment
PublicationGlass/polyester laminate coated with gelcoat layer of different thickness 0,5; 1,5; 3 mm was studied in terms of blistering behaviour and water sorption in hot water environment. Blistering was found to be accelerated for thin (0,5 mm) gel-coat layer compared to the thick (1,5; 3 mm), however no significant difference in blistering behaviour was observed between the laminates with gel-coat thickness 1,5 and 3 mm which may suggest...
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Natural/bio-based sorbents as greener extractive materials for endocrine disrupting compounds in samples of different matrix composition
PublicationEndocrine-disrupting compounds (EDCs) are a group of chemicals that interfere with the endocrine system, leading to adverse effects on human health and the environment. Increasing concerns over the EDCs presence in various environmental compartments has driven the search for greener extraction materials. Recently, the use of polymers of natural origin (biopolymers) has been demonstrated to be an effective and promising research...
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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,...