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Comparison of soil models in the thermodynamic analysis of a submarine pipeline buried in seabed sediments
PublicationThis paper deals with mathematical modelling of a seabed layer in the thermodynamic analysis of a submarine pipeline buried in seabed sediments. The existing seabed soil models: a “soil ring” and a semi-infinite soil layer are discussed in a comparative analysis of the shape factor of a surrounding soil layer. The meaning of differences in the heat transfer coefficient of a soil layer is illustrated based on a computational example...
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Viscoelastic lubrication on spherical slide bearing in impulsive unsteady motion.
PublicationNiniejsza praca przedstawia numeryczne i semi-analityczne wyznaczanie składowych wektora prędkości lepkosprężystego oleju, oraz wartości ciśnienia hydrodynamicznego i sił nośnych w sferycznym łożysku ślizgowym o zmieniającej się w czasie niesymetrycznej szczelinie smarnej podczas nieustalonego impulsywnego smarowania. Łożyska ślizgowe o czopach kulistych występują w maszynach transportowych w celu lepszego manewrowania ustawieniem...
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Detection of the acoustic interferences during AFM operation
Open Research DataAtomic force microscopy is a particularly complicated surface imaging technique due to the large number of factors that affect the quality of the resulting images. They are obviously difficult and sometimes even impossible to control at the same time. One of such factors may even be the seismological location of the building or the influence of mechanical...
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Properties of dimension witnesses and their semidefinite programming relaxations
PublicationIn this paper we develop a method for investigating semi-device-independent randomness expansion protocols that was introduced in Li et al. [H.-W. Li, P. Mironowicz, M. Pawłowski, Z.-Q. Yin, Y.-C. Wu, S. Wang, W. Chen, H.-G. Hu, G.-C. Guo, and Z.-F. Han, Phys. Rev. A 87, 020302(R) (2013)]. This method allows us to lower bound, with semi-definite programming, the randomness obtained from random number generators based on dimension...
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Expansion of the self of activists and nonactivists involved in mass gatherings for collective action
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Influence of High Temperature Oxidation on Hydrogen Absorption and Degradation of Zircaloy-2 and Zr 700 Alloys
PublicationThe present research was aimed at determining the effects of the oxide layers on hydrogen absorption, microstructure and mechanical properties of the Zircaloy- 2 and Zr 702 alloys. The oxidation was made at 350 °C, 700 °C and 900 °C for 10 to 30 min in laboratory air, followed by hydrogen cathodic charging for 72 h and annealing at 400 °C for 4 h. The slow strain rate tests were carried out on oxidized, charged and annealed specimens. The...
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Organic carbon fluxes of a glacier surface: a case study of Foxfonna, a small Arctic glacier
PublicationArctic glaciers are rapidly responding to global warming by releasing organic carbon (OC) to downstream ecosystems. The glacier surface is arguably the most biologically active and biodiverse glacial habitat and therefore the site of important OC transformation and storage, although rates and magnitudes are poorly constrained. In this paper, we present measurements of OC fluxes associated with atmospheric deposition, ice melt,...
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Detection of impulsive disturbances in archive audio signals
PublicationIn this paper the problem of detection of impulsive disturbances in archive audio signals is considered. It is shown that semi-causal/noncausal solutions based on joint evaluation of signal prediction errors and leave-one-out signal interpolation errors, allow one to noticeably improve detection results compared to the prediction-only based solutions. The proposed approaches are evaluated on a set of clean audio signals contaminated...
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A model of ship propulsion systems operating process.
PublicationArtykuł zawiera opis formalny procesu eksploatacji układów napędowych statków. Model tego procesu został przedstawiony w formie dwuwymiarowego procesu,, którego współrzędnymi są procesy semi-Markowa o skończonych zbiorach stanów. Jeden z tych procesów jest procesem zmian stanów technicznych układów napędowych a drugi „ procesem zmian ich stanów eksploatacyjnych. Zaproponowano także jednowymiarowy model procesu eksploatacji układów...
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Marek Wirkus dr hab. inż.
PeopleM. Sc. (1977 in the field of mechanical engineering technology and production management); Ph.D. degree in the field of Economic Sciences (1990; production management using IT techniques), habilitated doctor in the field of Economic Sciences, in the discipline of Management Sciences (2007 in the area of managing the portfolio of innovative projects); Co-creator of the Faculty of Management and Economics (1993); Vice Dean for Continuing...
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The Effect of Welding Conditions on Mechanical Properties of Superduplex Stainless Steel Welded Joints
PublicationThe tests results of superduplex stainless steel welded joints made with a different heat input, using automatic submerged arc welding (SAW) and semi-automatic flux-cored arc welding (FCAW) have been presented. Metallographic examinations, the measurements of the ferrite content, the width of the heat affected zone (HAZ) and the hardness of the welds in characteristic areas have been performed. Significant differences in the amount of...
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Jolanta Łopatowska dr inż.
PeopleJolanta Łopatowska, assistant professor at the Department of Management Engineering and Quality at the Faculty of Management and Economics, is a graduate of the Faculty of Electronics at Gdańsk University of Technology and Institute of Organization and Design of Production Systems at Gdańsk University of Technology. She obtained Ph.D. degree in the discipline of Economic Science. Her scientific and research interests focus on organizationally...
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Business process modelling
e-Learning CoursesWelcome to the Business Process Modeling course! We will travel together among the business processes world and its modeling with the BPMN ;) I hope it will be valuable for your future. See you soon, Marzena Grzesiak
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Hybrid fuzzy-ontological project framework of a team work simulation system
PublicationThe aim of this article is to present the project framework for constructing a Software Process Simulation Modeling (SPSM) system. SPSM systems can be used as a virtual environment for the selection of methods and tools of project management in IT support organizations. The constructed system simulates the Scrum methodology, including the management processes and the project roles. For the implementation of Scrum processes, the...
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Stanowisko do diagnostyki i regulacji wyzwalaczy przekaźników w obwodach lokomotyw elektrycznych
PublicationFast circuit breaker and protective relays play an important role of protecting locomotive’s electrical circuits from damage caused by short circuit or overload. Undisturbed operation and proper circuit protection depends on the technical condition and fine calibration of the over-current trips. Therefore the relays should be subject to periodic inspection and adjustment due to locomotive maintenance schedule. A test stand for...
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Austenitic stainless steel sensitization
Open Research DataHigh-alloy steels, thanks to their composition and content of appropriate alloying additives, are characterized by increased resistance to many corrosive environments. However, this is due to the increased sensitivity of the described construction materials to specific environmental conditions during their use. An example may be the increased susceptibility...
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Scattering and Propagation Analysis for the Multilayered Structures Based on Field Matching Technique
PublicationA semi-analytical method is employed to the analysis of scattering and guiding problems in multilayer dielectric structures. The approach allows to investigate objects with arbitrary convex cross section and is based on the direct field matching technique involving the usage of the field projection at the boundary on a fixed set of orthogonal basis functions. For the scattering problems the scattered field in the far zone is calculated...
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Koncepcje decyzyjnego sterowania procesem eksploatacji urządzeń technicznych z uwzględnieniem diagnostyki.
PublicationW artykule przedstawiono propozycję decyzyjnego sterowania procesem eksploatacji dowolnych urządzeń technicznych, np. silników spalinowych (tłokowych lub turbinowych) z zastosowaniem modelu tego procesu w formie decyzyjnego (sterowanego) procesu semi-markowskiego. Przedstawiono dowolne urządzenie techniczne jako obiekt sterowania. Zwrócono uwagę na potrzebę jednoczesnego sterowania procesem zmian stanów technicznych i procesem...
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Habitat-related patterns of soft-bottom macrofaunal assemblages in a brackish, low-diversity system (southern Baltic Sea)
PublicationCoastal areas provide a high variety of sedimentary habitats that influence the structure of resident fauna even on small geographical scales. Therefore, examinations of spatial variations in benthic assemblages require background knowledge of the environmental and biotic heterogeneity of habitats in order to understand ecological processes in such areas. The effect of habitat-related abiotic and biological variables on macrofaunal...
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A facile structural manipulation strategy to prepare ultra-strong, super-tough, and thermally stable polylactide/nucleating agent composites
PublicationPolylactide (PLA) is a biodegradable thermoplastic widely used in diferent felds, but it should be adequately modifed considering high-performance applications. However, the current processes for developing PLA materials achieve high strength at the expense of toughness or ductility of the materials. Therefore, there is need to develop new strategies for generation of PLA materials with high strength, great toughness, good ductility,...
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Multisine impedimetric monitoring with an in-depth distribution of relaxation times analysis of WE43 and AZ31 magnesium alloys corrosion
PublicationThis research aims to develop and utilize an impedance-based tool for monitoring non-stationary electrochemical processes, coupling the multisinusoidal perturbation signal approach and distribution of relaxation times (DRT) analysis for the first time. The approach was used to distinguish independent processes occurring at the surface of AZ31 and WE43 Mg alloys undergoing corrosion in Hank’s Balanced Salt Solution at 37 °C. We...
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Single-phase product obtained via crude glycerine depolymerisation of polyurethane elastomer: structure characterisation and rheological behaviour
PublicationPolyurethane recycling is a topic of growing interest due to the increasing amount of polyurethanewaste. The main purpose of polyurethane feedstock recycling is to recover the starting polyol, a valuable material. In thiswork, amethod of polyurethane thermo-chemical recycling, glycerolysisbymeansof crude glycerine, is proposed. Themaineffort is focusedonthe employment of crude glycerine without purification from biodiesel production...
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EVALUATION OF EFFECTIVENESS OF WATERJET PROPULSOR FOR A SMALL UNDERWATER VEHICLE
PublicationT he goal of the project described is to replace the existing propulsion system of a small underwater vehicle with a solution less prone to mechanical damage and ensuring a lower risk of the entanglement of fibrous objects suspended in the body of water. Four typical marine screws are utilised in the current design of the vehicle. One possible solution of the problem is the application of waterjet propulsors located...
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SOVtBAL Hybrid-powered low emission autonomous/semi-autonomous vessels for servicing off-shore wind farms
ProjectsProject realized in Institute of Mechanics and Machine Design
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Hybrid Fuzzy-Ontological Project Framework of a Team Work Simulation System
PublicationThe aim of this article is to present the project framework for constructing a Software Process Simulation Modeling (SPSM) system. SPSM systems can be used as a virtual environment for the selection of methods and tools of project management in IT support organizations. The constructed system simulates the Scrum methodology, including the management processes and the project roles. For the implementation of Scrum processes, the...
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On reliability assessment of ship machinery system in different autonomy degree; A Bayesian-based approach
PublicationAnalyzing the reliability of autonomous ships has recently attracted attention mainly due to epistemic uncertainty (lack of knowledge) integrated with automatic operations in the maritime sector. The advent of new random failures with unrecognized failure patterns in autonomous ship operations requires a comprehensive reliability assessment specifically aiming at estimating the time in which the ship can be trusted to be left unattended....
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Krzysztof Jan Kaliński prof. dr hab. inż.
PeopleKrzysztof J. Kaliński completed his MSc study at Gdańsk University of Technology (GUT) Faculty of Production Engineering (1980, result – get a first). He obtained PhD at GUT Faculty of Machine Building (1988, result – get a first), DSc at GUT Faculty of Mechanical Engineering (ME) (2002, result – get a first), and professor’s title – w 2013 r. In 2015 r. he became full professor.His research area includes: theoretical and applied...
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Wyniki sulfammox (SRAO)
Open Research DataTwo granular sequencing batch reactors were operated for 160 days under anammox conditions, comparing the Anammox process and Sulfate Reduction Ammonium Oxidation process. The study aimed to investigate whether increasing the concentration of SO42- could enhance N removal rates under anaerobic conditions, and whether SO42- reduction and anammox processes...
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Microscopic examination of CuNiFeR pipeline
Open Research DataCopper and nickel alloys called cunifers (Cu, Ni, Fe and R – rest of alloy elements) have found wide application in the production of ship pipeline components in contact with sea water, such as, for example, the main engine cooling system. These alloys are characterized by a very high corrosion resistance, which is ensured by appropriately carried out...
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Number of commercial banks at the end of the year, excluding banks that are not operating, bankrupt or liquidated, and banks in organization in 1993-2004
Open Research DataPolish banks were gradually transformed from enterprises with a predominance of Polish private capital into banks with a majority share of private foreign capital. In 1993, there were 48 banks with a majority of Polish private capital, and in 2006 there were 7 of them. In 1993, the shares of 10 banks in Poland were owned by private foreign capital,...
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Collective angst and collective action for progressive city policies: study1
Open Research DataPaweł Adamowicz, the liberal mayor of Gdańsk, died on January 14, 2019, after being stabbed by a man who rushed onstage during a charity event. Three studies were carried out to analyze the predictors of willingness to engage in collective action for the support of the progressive city policies he initiated. In this study 1 (N = 214), the questionnaire,...
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Macroscopic examination of CuNiFeR pipeline
Open Research DataCopper and nickel alloys called cunifers (Cu, Ni, Fe and R – rest of alloy elements) have found wide application in the production of ship pipeline components in contact with sea water, such as, for example, the main engine cooling system. These alloys are characterized by a very high corrosion resistance, which is ensured by appropriately carried out...
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Imaging and chemical investigation of silver coating
Open Research DataThe recovery of silver from materials such as plates, still used in clinical radiography [1], or scrap jewelery is still very popular. The subject of the research, part of which was microscopic imaging, was to recreate the behavior of an electrochemically deposited silver coating. The copper electrodes were covered with a layer of silver obtained from...
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The use of Acoustic Emission to identification damages bearings the main and crank engines about the automatic ignition
PublicationThe article describes the laboratory tests, which make the first stage of the study concerning the use of the AE method to determine the technical state of the slide bearings in engines with self-ignition. The aim of the present tests was to compare the recorded signals in relation to the technical state of the material of the bearing bush and to check the possibility of using the AE method in determining the transition moment...
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New sample preparation strategies for comprehensive lipidomics of human breast milk
PublicationGLOBAL PROFILING ANALYSIS OF HUMAN BREAST MILK (HBM) LIPIDS IS HINDERED BY COMPLEX COMPOSITION OF HBM. THIS PROBLEM IS HUGE FROM ANALYTICAL POINT OF VIEW, SINCE DUE TO THAT DETECTION OF ALL HBM LIPIDS DURING ONE ANALYTICAL RUN IS LIMITED. THUS, SAMPLE PREPARATION STEP CONSTITUTES A CRUCIAL STEP IN UNTARGETED LIPIDOMIC ANALYSIS OF HBM, ESPECIALLY WHEN SEMI-QUANTITATIVE ANALYSIS IS ASSUMED. HEREIN, WE PRESENT A COMPARISON OF PUBLISHED...
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Big Data Processing by Volunteer Computing Supported by Intelligent Agents
PublicationIn this paper, volunteer computing systems have been proposed for big data processing. Moreover, intelligent agents have been developed to efficiency improvement of a grid middleware layer. In consequence, an intelligent volunteer grid has been equipped with agents that belong to five sets. The first one consists of some user tasks. Furthermore, two kinds of semi-intelligent tasks have been introduced to implement a middleware...
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Supporting Management Decisions with Intelligent Mechanisms of Obtaining and Processing Knowledge
PublicationThis paper is a summary of the authors' work on a model of support for decision processes in organisation management. Key decisions in organisations are often made without sufficient knowledge and by people lacking the proper qualifications and experience. Without full support in decision processes, true threats to organisations are created. Therefore, to support decision processes in numerous organisations, apart from experts...
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Theoretical study of highly-excited states of KRb molecule
PublicationSemi-empirical adiabatic potential energy curves of highly excited states of the KRb molecule are calculated as a function of the internuclear distance R over a wide range from 3 to 150 a0. The diatomic molecule is treated as an effective two-electron system by using the large core pseudopotentials and core polarization potentials. All calculations are performed by using the nonrelativistic CASSCF/MRCI method with accurate basis...
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Effect of polymer fibres reinforcement on selected properties of asphalt mixtures
PublicationThe paper presents selected results of the research program concerning fibre reinforced asphalt concrete. Aramid-polyalphaolefin fibres was used in this study. Selected properties responsible for low temperature cracking and resistance to permanent deformation are presented in this paper. Low temperature cracking susceptibility was evaluated with the results obtained from bending test of rectangular beams with constant rate of...
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Beam on elastic foundation with anticlastic curvature: Application to analysis of mode I fracture tests
PublicationA first order correction is proposed taking into account both interface elasticity and transverse anticlastic curvature of flexible substrate(s) in the DCB (and related tests). Adherends are represented by Kirchhoff-Love plates, and the interface by Winkler-type elastic foundation. Two functions are introduced, representing evolution of beam deflection along the sample midline and anticlastic curvature along the plate. A method...
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Recent advances in aqueous virus removal technologies
PublicationThe COVID-19 outbreak has triggered a massive research, but still urgent detection and treatment of this virus seems a public concern. The spread of viruses in aqueous environments underlined efficient virus treatment processes as a hot challenge. This review critically and comprehensively enables identifying and classifying advanced biochemical, membrane-based and disinfection processes for effective treatment of virus-contaminated...
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Effective method of treatment of effluents from production of bitumens under basic pH conditions using hydrodynamic cavitation aided by external oxidants
PublicationUtilization of cavitation in advanced oxidation processes (AOPs) is a promising trend in research on treatment of industrial effluents. The paper presents the results of investigations on the use of hydrodynamic cavitation aided by additional oxidation processes (O3/H2O2/Peroxone) to reduce the total pollution load in the effluent from the production of bitumens. A detailed analysis of changes in content of volatile organic compounds...
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EXAMINING INFLUENCE OF VIDEO FRAMERATE AND AUDIO/VIDEO SYNCHRONIZATION ON AUDIO-VISUAL SPEECH RECOGNITION ACCURACY
PublicationThe problem of video framerate and audio/video synchronization in audio-visual speech recogni-tion is considered. The visual features are added to the acoustic parameters in order to improve the accuracy of speech recognition in noisy conditions. The Mel-Frequency Cepstral Coefficients are used on the acoustic side whereas Active Appearance Model features are extracted from the image. The feature fusion approach is employed. The...
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EXAMINING INFLUENCE OF VIDEO FRAMERATE AND AUDIO/VIDEO SYNCHRONIZATION ON AUDIO-VISUAL SPEECH RECOGNITION ACCURACY
PublicationThe problem of video framerate and audio/video synchronization in audio-visual speech recognition is considered. The visual features are added to the acoustic parameters in order to improve the accuracy of speech recognition in noisy conditions. The Mel-Frequency Cepstral Coefficients are used on the acoustic side whereas Active Appearance Model features are extracted from the image. The feature fusion approach is employed. The...
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Tensile test of part of CuNiFeR pipeline
Open Research DataCopper and nickel alloys called cunifers (Cu, Ni, Fe and R – rest of alloy elements) have found wide application in the production of ship pipeline components in contact with sea water, such as, for example, the main engine cooling system. These alloys are characterized by a very high corrosion resistance, which is ensured by appropriately carried out...
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Jacek Ryl dr hab. inż.
PeopleI have obtained my PhD in chemical technology in 2010. In the same year, I was employed at the Department of Electrochemistry, Corrosion and Materials Engineering at the Faculty of Chemistry. In 2018 I received habilitation at the Faculty of Chemistry GUT in technical sciences in the discipline of chemical technology. From 2021, he was employed at the Institute of Nanotechnology and Materials Science at the Faculty of Technical...
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Imaging of the effects of pitting corrosion with the use of AFM
Open Research DataPitting corrosion is a local attack on a metal surface, limited to a point or small area, which appears as a hole. Pitting corrosion is one of the most harmful forms of corrosion due to the fact that it is associated with small, difficult to detect damage, that can even lead to perforation of the structure. A single pit may range in size from micrometers...
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Oznaczanie tlenu – od metody Winklera do czujników enzymatycznych (Determination of oxygen – from Winkler Method to enzymatic sensor)
PublicationMonitoring of dioxygen levels is of utmost importance from the view-point of life processes, medical diagnostics, nutrition and chemical industries. In all these measurements both low and high levels of this element are important. The common methods for the determination of dioxygen are the Winkler method, Clark electrode and pulsoxymeters. A new, already strong field of research can be now recognized – the development of miniaturized...
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Bridging the gap between business process models and use-case models
PublicationToday's software development methodologies are equipped with a plethora of methods and techniques for business process engineering and Requirements Engineering. However, heavy investments in IT have not brought forth expected results. What seems to be lacking is a systematic approach that consolidates both disciplines to gain a synergistic effect. To address this challenge we extend Use-Case Driven Approach (UCDA) by binding use...
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Application of Multivariate Analysis Methods in Welding Engineering
PublicationPhenomena and processes taking place during welding are usually very complex and, for this reason, should be described using multivariate methods. The article discusses the methodological basis and selected application areas as regards the solving of welding problems using statistical multivariate methods. In addition, the article presents exemplary applications of the design of experiment, multiple regression analysis, cluster...