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Entanglement and Nonlocality are Inequivalent for Any Number of Parties
PublikacjaUnderstanding the relation between nonlocality and entanglement is one of the fundamental problems in quantum physics. In the bipartite case, it is known that these two phenomena are inequivalent, as there exist entangled states of two parties that do not violate any Bell inequality. However, except for a single example of an entangled three-qubit state that has a local model, almost nothing is known about such a relation in multipartite...
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System for tracking multiple trains on a test railway track
PublikacjaSeveral problems may arise when multiple trains are to be tracked using two IP camera streams. In this work, real-life conditions are simulated using a railway track model based on the Pomeranian Metropolitan Railway (PKM). Application of automatic clustering of optical flow is investigated. A complete tracking solution is developed using background subtraction, blob analysis, Kalman filtering, and a Hungarian algorithm. In total,...
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System for tracking multiple trains on a test railway track
PublikacjaSeveral problems may arise when multiple trains are to be tracked using two IP camera streams. In this work, real-life conditions are simulated using a railway track model based on the Pomeranian Metropolitan Railway (PKM). Application of automatic clustering of optical flow is investigated. A complete tracking solution is developed using background subtraction, blob analysis, Kalman filtering, and a Hungarian algorithm. In total,...
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Modification of the operating point of residual current transformers for high frequency earth fault currents detection
PublikacjaFor protection against electric shock in low voltage systems residual current devices are commonly used. However, their proper operation can be interfered when earth fault current with high frequency components occurs. Serious hazard of electrocution exists then. One of the most important element of residual current devices is a residual current transformer with iron core. Tripping characteristic of residual current devices strictly...
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Numerical estimation of the pile toe and shaft unit resistances during the installation process in sands
PublikacjaNumerical simulations of a pile jacking were carried out. A Coupled Eulerian–Lagrangian (CEL) formulation was used to treat with large deformation problems. An Abaqus, a commercial Finite Element Method software suit, was used as a computing environment. The Mohr–Coulomb constitutive model was applied and the Coulomb model of friction was used to describe pile-soil interaction. Calculations were made for three different pile diameters....
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Modified DNA polymerases for PCR troubleshooting
PublikacjaPCR has become an essential tool in biological science. However, researchers often encounter problems with difficult targets, inhibitors accompanying the samples, or PCR trouble related to DNA polymerase. Therefore, PCR optimization is necessary to obtain better results. One solution is using modified DNA polymerases with desirable properties for the experiments. In this article, PCR troubleshooting, depending on the DNA polymerase...
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Design of horizontal axis wind and water turbines
PublikacjaThe basic hydrodynamic principles of horizontal axis turbines are presented. Computational methods based on vortex theory for design of such turbines and for calculation of their hydro or aerodynamic characteristics are described in detail. These methods are applicable both to wind and water turbines. The influence of detailed turbine geometry on its characteristics is presented. Several practical computational examples of different...
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The Finite Elements Method application to assesment the impact of turbulence generated by wind turbines on their lacation inclose proximity of overhead high voltage power transmissionlines
PublikacjaThe paper presents selected aspects of construction of wind turbines location concerning aerodynamic impact on power lines. Reaserch is based on the source data concerning the aerodynamic impact of a wind farm consisting of 8 turbines and 400 kV power line, an analysis of the possibility of wind farm locating in the immediate vicinity of the line was carried out. There are serious problems with locating higher capacity wind farms...
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Weldability of high strength steels in wet welding conditions
PublikacjaIn this paper are characterized problems of high strength steel weldability in underwater wet welding conditions. Water as a welding environment intensifies action of unfavourable factors which influence susceptibility to cold cracking of welded steel joints. The susceptibility to cold cracking of S355J2G3 steel and S500M steel in wet conditions was experimentally estimated (by using Tekken test). It was concluded that the steels...
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Test Design Patterns for Embedded Systems,
PublikacjaTest suites for embedded systems are typically created from scratch using dif- ferent, often inadequate methods. In consequence, industry branches dealing with software-intensive embedded systems have to cope with quality problems, even though test processes are particularly time-consuming and costly. Based on an evolving model-based testing methodology we introduce test design patterns for simplifying and accelerating...
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Arch./Urban Project II
Kursy OnlineA design studio focused on issues related to the creation of sustainable and climate-responsible facilities. The design task is related to the concept of development of the Gdańsk University of Technology campus. The implemented project will be both a task related to urban and architectural design. A very important element of the design process will be a smooth transition between various scales and problems that architects and...
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Nanotechnologia w architekturze – korzyści i problemy wynikające z zastosowania nanotechnologii w aspekcie cyklu życia budynku
PublikacjaDynamiczny rozwój technologii zawsze odgrywał ważną rolę w procesie kształtowania architektury. Postęp w dziedzinie inżynierii materiałowej już od Rewolucji Przemysłowej pozwalał na osiąganie co raz bardziej skomplikowanych i jednocześnie wytrzymałych konstrukcji budynków. Obecnie, w dziedzinie architektury, zaczyna pojawiać się pojęcie nanotechnologii, która pozwala zmieniać stosowane materiały w bardziej wydajne i odporne....
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Image simulation and annotation for color blinded
PublikacjaIn this paper methods for image simulation as seen by a color blinded and a method for constructing images of perceived color difference are presented. The work is also focused on the interactive color description of an image contents. As a result, the individuals having problems with color discrimination can identify colors in an image.W artykule prezentowane są metody symulacji kolorów w obrazach postrzeganych przez osoby ze...
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Voltage Harmonic Distortion Measurement Issue in Smart-Grid Distribution System
PublikacjaThis paper presents the investigation results ofvoltage harmonic transfer accuracy problems through voltagetransformers which are widely used in power quality monitoringsystems in medium and high voltage grids. A simplified lumpedparameters circuit model of the voltage transformer is presentedand verified by simulation and experimental investigations. Anumber voltage transformers typically used in medium voltagegrid has been tested...
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Important Facts and Observations about Pairwise Comparisons (the special issue edition)
PublikacjaThis study has been inspired by numerous requests for clarification from researchers who often confuse Saaty’s Analytic Hierarchy Process (AHP) with the pairwise comparisons (PC) method, taking AHP as the only representation of PC. This study should be regarded as an interpretation and clarification of past investigations of PC. In addition, this article is a reflection on general PC research at a higher level of abstraction: the...
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Large thermo-elastic displacement and stability FEM analysis of multilayered plates and shells
PublikacjaThe paper concerns the load capacity analysis of thermally loaded multilayered plates and shells. The multilayered body is treated as an equivalent single layer whose kinematics is consistent with first order shear deformation theory. The authors focus on the thermo-elastic stability problem of the thin-walled structures. The equilibrium paths are traced with the use of Riks-Wempner-Ramm algorithm. By making use of the Tsai-Wu...
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“Project-factor-decision”. Decisive factors in IT projects and their impact on its success
PublikacjaThe aim of this article is to indicate the need for a deepening, systematizing and codifying of the theoretical and practical knowledge on IT project management, in the area of management decision-making processes. The scope of decisions made by managers is constantly on the increase. Project managers make decisions not only within the classic triangle of constraints, which consists of a schedule, a budget and the project scope,...
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SENSORY GARDENS INCLUSIVELY DESIGNED FOR VISUALLY IMPAIRED USERS.
PublikacjaThis paper discusses the design of sensory gardens, created especially to provide for the needs of sight impaired children and youth. These gardens should be inclusively available to general public. A sensory garden may have both therapeutic and educational effects. The research findings concerning therapeutic effects of contact with nature on children and youth are reviewed. The design problems related to providing a space for...
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Forecasted climate changes and their influence on cities and regions in 2050 in terms of extreme hydrological events
PublikacjaGlobal climate change is a problem which arises numerous theories and uncertainties, especially in terms of speculated human impact. Independent from the fact, what is the main driver for the changes, some of the climate shifts are visible already nowadays. Both contemporary and future cities will have to face such problems. Although climate change may cause numerous effects on different fields, a special stress in this article...
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Dynamic Response of the Suspended on a Single Cable Footbridge
PublikacjaThe article presents numerical simulations, dynamic in situ load tests and a structural health monitoring (SHM) system installed in a suspended on a single cable footbridge. Numerical simulations performed prior to construction indicated the possibility of structural dynamics problems, finally confirmed in the course of dynamic test loading. In the dynamic load course the bridge deck developed vibrations displaying accelerations...
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Numerical tests of time-stepping schemes in the context of FEM for 6-field shell dynamics
PublikacjaThe paper deals with integration of dynamic equations of irregular shells performed with relatively long time steps. Numerical instability appearing often in this kind of analysis motivated the authors to present some studies based on numerical tests referring to convergence problems of finite element analysis as well the applied stability conditions. The analysis is carried out on simulations of shell dynamics with the where the...
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Evaluation of Face Detection Algorithms for the Bank Client Identity Verification
PublikacjaResults of investigation of face detection algorithms efficiency in the banking client visual verification system are presented. The video recordings were made in real conditions met in three bank operating outlets employing a miniature industrial USB camera. The aim of the experiments was to check the practical usability of the face detection method in the biometric bank client verification system. The main assumption was to provide...
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Degradation of protective coatings in steel chimneys of flue gas desulfurisation system
PublikacjaThis paper presents problems associated with corrosion of steel stacks and changes in philosophy of corrosion protection when implemented into flue gas desulphurization systems. In-situ tests were taken by means of electrochemical impedance spectroscopy at the stack which discharges flue gas before wet lime/limestone desulphurization. A very quick electrolyte absorption by the spherical infill vinylester coating was found using...
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When Neural Networks Meet Decisional DNA: A Promising New Perspective for Knowledge Representation and Sharing
PublikacjaABSTRACT In this article, we introduce a novel concept combining neural network technology and Decisional DNA for knowledge representation and sharing. Instead of using traditional machine learning and knowledge discovery methods, this approach explores the way of knowledge extraction through deep learning processes based on a domain’s past decisional events captured by Decisional DNA. We compare our approach with kNN (k-nearest...
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Shielded coupled strip and slot guides with a thin omega pseudochiral medium layer
PublikacjaA method of moments combined with mode matching technique is applied to analyze the shielded coupled strip and slot line structures containing a thin plate of Omega pseudochiral medium. The boundary problems are simplified by introducing for omega medium the approximate continuity conditions. Such mathematical model allows to examine the field displacement effect appearing in the considered guide resulting from the coupling between...
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Absorbing Boundary Conditions Derived Based on Pauli Matrices Algebra
PublikacjaIn this letter, we demonstrate that a set of absorbing boundary conditions (ABCs) for numerical simulations of waves, proposed originally by Engquist and Majda and later generalized by Trefethen and Halpern, can alternatively be derived with the use of Pauli matrices algebra. Hence a novel approach to the derivation of one-way wave equations in electromagnetics is proposed. That is, the classical wave equation can be factorized...
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Modeling DAC Application Execution Time
PublikacjaAn 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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Hybrid Method Analysis of Unshielded Guiding Structures
PublikacjaA combination of mode matching, finite element methods and generalized impedance matrix is presented in a context of propagation problems for open guiding structures. The computational domain is divided into two regions: the first one is a circular cylinder containing whole guiding structure and the second one surrounds this artificial cylinder. The impedance matrix is calculated with the use of finite element method in the first...
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Weighted 2-sections and hypergraph reconstruction
PublikacjaIn the paper we introduce the notion of weighted 2-sections of hypergraphs with integer weights and study the following hypergraph reconstruction problems: (1) Given a weighted graph , is there a hypergraph H such that is its weighted 2-section? (2) Given a weighted 2-section , find a hypergraph H such that is its weighted 2-section. We show that (1) is NP-hard even if G is a complete graph or integer weights w does not exceed...
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Weak Solutions within the Gradient-Incomplete Strain-Gradient Elasticity
PublikacjaIn this paper we consider existence and uniqueness of the three-dimensional static boundary-value problems in the framework of so-called gradient-incomplete strain-gradient elasticity. We call the strain-gradient elasticity model gradient-incomplete such model where the considered strain energy density depends on displacements and only on some specific partial derivatives of displacements of first- and second-order. Such models...
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On Applications of Fractional Derivatives in Electromagnetic Theory
PublikacjaIn this paper, concepts of fractional-order (FO) derivatives are analysed from the point of view of applications in the electromagnetic theory. The mathematical problems related to the FO generalization of Maxwell's equations are investigated. The most popular formulations of the fractional derivatives, i.e., Riemann-Liouville, Caputo, Grünwald-Letnikov and Marchaud definitions, are considered. Properties of these derivatives are...
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Audio-visual aspect of the Lombard effect and comparison with recordings depicting emotional states.
PublikacjaIn this paper an analysis of audio-visual recordings of the Lombard effect is shown. First, audio signal is analyzed indicating the presence of this phenomenon in the recorded sessions. The principal aim, however, was to discuss problems related to extracting differences caused by the Lombard effect, present in the video , i.e. visible as tension and work of facial muscles aligned to an increase in the intensity of the articulated...
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Zastosowanie podejścia holistycznego w zrównoważonej rewitalizacji nabrzeży i terenów poportowych
PublikacjaGeneza zdegradowanych nabrzeży i obszarów poportowych. Problemy rewitalizacji obszarów nadwodnych. Aspekty organizacyjne rewitalizacji. Holistyczne podejście w rewitalizacji nabrzeży i terenów poportowych. Zasoby i potencjał terenów nadwodnych.
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Дослідження проблем зайнятості випускників навчальних закладів
PublikacjaУ зв'язку зі зниженням загального рівня зайнятості та з огляду на кризові явища в українській економіці актуальною залишається проблема працевлаштування молоді. Спільність проблеми зайнятості випускників вишів як в Україні, так і в Європі дала змогу провести міжнародне дослідження, щоб виявити основні причини її виникнення. Результати досліджень підтвердили гіпотезу авторів. В її основі лежить комплекс причин, що пов’язані як зі...
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FPGA implementation of the multiplication operation in multiple-precision arithmetic
PublikacjaAlthough standard 32/64-bit arithmetic is sufficient to solve most of the scientific-computing problems, there are still problems that require higher numerical precision. Multiple-precision arithmetic (MPA) libraries are software tools for emulation of computations in a user-defined precision. However, availability of a reconfigurable cards based on field-programmable gate arrays (FPGAs) in computing systems allows one to implement...
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Concrete versus green corridors in road planning. Gdansk case
PublikacjaThe aim of an article is to present the threats which may be caused by the construction of the transit road inside the city structure, and some mitigation measures aiming to eliminate or minimize environmental and landscape damages and social problems. Theoretical guidelines and conclusions will be followed by the example illustrating the problem. As an answer, some guidelines enabling sustainable road planning will be presented....
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Potential for ITS/ICT Solutions in Urban Freight Management
PublikacjaThe article presents a study on applying ITS solutions in planning and management of urban freight transport in Gdynia. The traffic management system Tristar which is under implementation and its related systems show a potential to assist in development of freight transport measures. Recommendations for urban freight policy development supplementing Gdynia's Sustainable Urban Mobility Plan were used as a basis for identification...
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On Tradeoffs Between Width- and Fill-like Graph Parameters
PublikacjaIn this work we consider two two-criteria optimization problems: given an input graph, the goal is to find its interval (or chordal) supergraph that minimizes the number of edges and its clique number simultaneously. For the interval supergraph, the problem can be restated as simultaneous minimization of the path width pw(G) and the profile p(G) of the input graph G. We prove that for an arbitrary graph G and an integer t ∈ {1,...
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Simulating propagation of coherent light in random media using the Fredholm type integral equation
PublikacjaStudying propagation of light in random scattering materials is important for both basic and applied research. Such studies often require usage of numerical method for simulating behavior of light beams in random media. However, if such simulations require consideration of coherence properties of light, they may become a complex numerical problems. There are well established methods for simulating multiple scattering of light (e.g....
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Refinement of the Hardening Soil model within the small strain range
PublikacjaThe popularity of the elasto-plastic Hardening Soil (HS) model is based on simple parameter identification from standard testing and empirical formulas. The HS model is implemented in many commercial FE codes designed to analyse geotechnical problems. In its basic version, the stress–strain behaviour within the elastic range is subject to the hypoelastic power law, which assures the barotropy of the elastic stiffness. However,...
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Narratives on cutting down trees on private land. A comparison of urban and rural municipalities in Poland using the Q-deliberation method
PublikacjaIncreased development in rural and urban areas leads to a decrease in tree cover and reduces the ecosystem services that trees provide. Municipal authorities must consider managing trees on private land to ensure that residents have access to trees and green spaces. In doing so, they must frequently confront conflicting stakeholder views, which are driven by diverse public and private interests and impacted by the type of landscape...
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Wielokryterialne Wspomaganie decyzji środowiskowych przy wydobywaniu węglowodorów z formacji łupkowych
PublikacjaPoszukiwanie i eksploatacja gazu z formacji łupkowych wymaga zidentyfikowania i uwzględnienia wielu czynników i uwarunkowań geologiczno-górniczych, ekonomiczno-finansowych, prawnych oraz szeroko rozumianych aspektów przestrzenno-środowiskowych. Poruszane zagadnienia prowadzą do zidentyfikowania problemów decyzyjnych, które mogą pojawiać się przy eksploatacji gazu z łupków, a które wiążą się z intensywnym korzystaniem z zasobów...
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Marcin Potrykus dr inż.
OsobyAbsolwent Wydziału Zarządzania i Ekonomii Politechniki Gdańskiej. Od 2008 zatrudniony jako Asystent w Katedrze Finansów na Wydziale Zarządzania i Ekonomii Politechniki Gdańskiej. W 2015 roku obronił (w dyscyplinie ekonomia) rozprawę doktorską zatytułowaną „Inwestycje alternatywne – opłacalność a ryzyko”. Od 2016 zatrudniony jako adiunkt w Katedrze Analizy Ekonomicznej i Finansów na Politechnice Gdańskiej. Jego zainteresowania naukowe...
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VERSATILE SPACE OF PERSIAN COURT HOUSE IN ISFAHAN USED AS POLISH CHILDREN HABITAT DURING THE WW2
PublikacjaDuring WW2 thousands of Polish citizens were deported to Siberia and Kazakhstan in the USSRdoomed to exterminating labour. The Polish army was also detained there. The Iranian Shahallowed Polish soldiers and civilians to cross from Russia to Iran. In Isfahan Polish fugitives, mainlychildren, were accommodated in Persian traditional court houses which were converted into theirtemporary habitat, where new...
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Speed sensorless ac drive with inverter output filter and fault detection using load torque signal
PublikacjaIn this paper, a sensorless induction motor (IM) drive using speed observer system is presented. The system includes load torque computation for gear fault detection. Nonlinear control method is adopted for controlling the motor over a wide speed range. An LC filter for smoothing current and voltage waveforms is used at the output of the voltage inverter. The use of filter imposes more building of the used observer to avoid using...
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Voltage Transients Transfer over Medium Voltage Instrument Transformers
PublikacjaThis paper presents voltage harmonic transfer accuracy problems through voltage transformers which are used in power quality monitoring systems in medium and high voltage grids. A simplified lumped parameters circuit model of the voltage transformer is proposed and verified by simulation and experimental investigations. A number voltage transformers typically used in medium voltage grid has been tested in the conducted disturbances...
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Voltage Harmonics Transfer through Medium Voltage Instrument Transformers
PublikacjaVoltage transformers are widely used in power quality monitoring systems in medium and high voltage grids. This paper presents accuracy problems related to voltage harmonics transfer through instrument transformers. A simplified lumped-parameters wideband circuit model of the voltage transformer is proposed and verified by simulation and experimental investigations. A number of voltage transformers have been tested in the frequency...
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Application of Maximum-Length Sequences to impulse response measurement of hydroacoustic communications systems
PublikacjaThere is a growing interest in digital transmission of telemetry data on ultrasonic waves. The dependence of signal attenuation on squared frequency, specific to the hy-droacoustic systems, induces problems that do not exist in monochromatic, narrowband radio communications systems. For adapting the transmission parameters to current propagation conditions, a precise knowledge of instantaneous changes of channel performances is...
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Cold Cracking Of Underwater Wet Welded S355G10+N High Strength Steel
PublikacjaWater as the welding environment determines some essential problems influencing steel weldability. Underwater welding of high strength steel joints causes increase susceptibility to cold cracking, which is an effect of much faster heat transfer from the weld area and presence of diffusible hydrogen causing increased metal fragility. The paper evaluates the susceptibility to cold cracking of the high strength S355G10+N steel used,...
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Noise related to gas bottles explosions
PublikacjaModern industrialized world is in a never ending danger of accidents and catastrophes of technical nature. Some of them may involve fires and explosions of gas storage bottles or containers. Technical University of Gdansk, Poland performed numerous tests where bottles containing acetylene, oxygen, hydrogen, CO2, LPG, LNG or CNG were blown due to excessive temperature caused by fire. Although those experiments were not focused on...