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Search results for: underwater acoustic communications
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Multi-criterion, evolutionary and quantum decision making in complex systems
PublicationMulti-criterion, evolutionary and quantum decision making supported by the Adaptive Quantum-based Multi-criterion Evolutionary Algorithm (AQMEA) has been considered for distributed complex systems. AQMEA had been developed to the task assignment problem, and then it has been applied to underwater vehicle planning as another benchmark three-criterion optimization problem. For evaluation of a vehicle trajectory three criteria have...
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Tibor Cinkler prof. dr hab. inż.
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5G Technologies in Intelligent Transport Systems - Architectures, Virtualization and Network Slicing
PublicationIn the paper, 5G communication technologies implemented for Intelligent Transport Systems are discussed. Firstly, the essence of the 5G system concept is presented, and the problem of network functions virtualization (NFV) is analyzed. Moreover, the principle of virtualization is explained. Secondly, the analysis of network slicing is performed, from the point of view of transport systems implementation in the...
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An Empirical Model for the Polarisation Characteristics of Indoor Off-Body Channels
PublicationThis paper presents an analysis of the polarisation characteristics for the channel in dynamic off-body communications, and an empirical channel model, based on measurements performed at 2.45 GHz in an office environment. Body presence and propagation conditions have a strong influence on signal depolarisation. The model assumes three components for the total path loss: mean path loss, represented by a log-distance function with...
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Practical Trial for Low-Energy Effective Jamming on Private Networks With 5G-NR and NB-IoT Radio Interfaces
PublicationFourth-generation (4G) mobile networks are successively replaced by fifth-generation (5G) ones, based on the new releases of the 3rd Generation Partnership Project (3GPP) standard. 5G generation is dedicated to civilian users and the conducted analytical work shows that it has numerous technological gaps that prevent its direct implementation in military communications systems. However, the recent armed world conflicts showed that...
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Remote Work Support Needs of Employees with Autism Spectrum Disorder in Poland: Perspectives of Individuals with Autism and Their Coworkers
PublicationBackground and Aims: With remote work becoming more common across industries, employees with autism may experience different work support needs from neurotypical peers. However, the specific remote work needs of this group of employees are underexplored in the literature. We aim to propose ways to assess workplace digital adaptation needs for individuals with autism and a framework for communicating these needs to employers. Methods:...
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WPŁYW KAUSTYKI NA AKUSTYKĘ GROT SZEPTÓW W PARKU OLIWSKIM W GDAŃSKU
PublicationW pracy omówiono kaustykę jako uporządkowaną formę rozmycia ogniska, tworzonego przez zwierciadło wklęsłe. Zaprezentowano przykład kaustyki powstającej przy odbiciu światła od zwierciadła wklęsłego. Na tym tle wskazano na możliwość powstawania kaustyk w pomieszczeniach. Szczególną uwagę zwrócono na duże pomieszczenia o charakterze historycznym, ze względu na częstą obecność w nich zwierciadeł akustycznych w postaci sklepień i...
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USŁUGA RÓWNOWAŻENIA OBCIĄŻENIA W SYSTEMIE OPENSTACK
PublicationNiniejszy artykuł ma na celu pokazanie funkcjonowania równoważenia obciążenia dla serwisu Neutron odpowiedzialnego za tworzenie i obsługę usług sieciowych dla użytkowników OpenStack’a. Stanowi on podstawę do zapewnienia komunikacji wewnątrz systemowej, z systemem jak i z wewnętrznymi prywatnymi sieciami systemowymi. W artykule przedstawiono wyniki bazując na edycji Juno, którą zaimplementowano w celu przeprowadzenia badań i analizy...
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The Innovative Faculty for Innovative Technologies
PublicationA leaflet describing Faculty of Electronics, Telecommunications and Informatics, Gdańsk University of Technology. Multimedia Systems Department described laboratories and prototypes of: Auditory-visual attention stimulator, Automatic video event detection, Object re-identification application for multi-camera surveillance systems, Object Tracking and Automatic Master-Slave PTZ Camera Positioning System, Passive Acoustic Radar,...
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Adaptive Personal Tuning of Sound in Mobile Computers
PublicationAn integrated methodology for enhancing audio quality in mobile computers is presented. The key features are adaptation of the characteristics of their acoustic track to changing acoustic conditions of the environment and to users’ individual preferences. Signal processing algorithms are introduced that concern: linearization of frequency response, dialogue intelligibility enhancement, and dynamics processing tuned up to the users’...
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Adaptive system for recognition of sounds indicating threats to security of people and property employing parallel processing of audio data streams
PublicationA system for recognition of threatening acoustic events employing parallel processing on a supercomputing cluster is featured. The methods for detection, parameterization and classication of acoustic events are introduced. The recognition engine is based onthreshold-based detection with adaptive threshold and Support Vector Machine classifcation. Spectral, temporal and mel-frequency descriptors are used as signal features. The...
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A Novel Multicast Architecture of Programmable Networks
PublicationIn the paper a multicast architecture for programmable networks based on separation of group management and network control tasks is proposed. Thanks to this separation, services which want to make use of multicast communications no longer have to implement low-level network functionalities and their operation is greatly simplified. Abstracting service’s view of the network into a fully connected cloud enables us to transparently...
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Cybersecurity and Privacy in Standards for Smart Grids – a Comprehensive Survey
PublicationResilient information and communications technologies are a prerequisite for reliable operation of smart grid. In recent years, many standards for the new form of electricity network have been proposed, which results in operators and other smart grid stakeholders having difficulties in finding the documents which can be related to their particular problems. The purpose of this paper is to bring in all smart grid standards that...
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The shallow sea experiment with usage of linear hydrophone array
PublicationPurpose of this article is to present designed and made linear hydrophone array and the results obtained during in situ trails on Gulf of Gdańsk. The measuring system allowed to localize hydrophones in the selected points and perform measurements in both the horizontal antenna positioning and vertical. Made in this way recordings allow creating accurate 3D imaging of sound intensity/propagation. During research three floating objects...
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Jaroslaw Spychala dr
PeopleOprócz bardzo dobrego wykształcenia osoba posiada również wieloletnie doświadczenie zawodowe, które jest poświadczeniem tego, że potrafi wykorzystać swoją wiedzę teoretyczną w praktycznych działaniach. Doświadczenie zawodowe jest bardzo bogate i rozbudowane. Ze względu na nabyte całkiem nowe umiejętności zwiększa się atrakcyjność doświadczonego pracownika. Są to między innymi kreatywne myślenie, zorientowanie na cel, odporność...
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Investigation of Transmit and Receive Characteristics of Laboratory Model for the Parametric Echosounder
PublicationInvestigation and operation of devices based on nonlinear interaction of high-intensity waves have been carried out for several decades. However, it is still a new tool to study the properties of the water environment and especially the upper layers of the seabed. This paper describes the results of tests of the new device that is intended to be applied for sounding underwater areas. The device has been designed and built in collaboration with...
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Effect of shielded electrode wet welding conditions on diffusible hydrogen content in deposited metal
PublicationWet welding is the most popular method of joining in water enviroment. During underwater welding, the weldability of steel is limited by the higher cooling rates and hydrogen content in weld metal. Article presents results of preliminary tests on the effects of wet welding conditions on diffusible hydrogen amount. Seven parameters were optimized using a Plackett-Burman plan to get the most relevant variables. These parameters were:...
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Highly effective degradation of selected groups of organic compounds by cavitation based AOPs under basic pH conditions
PublicationCavitation has become on the most often applied methods in a number of industrial technologies. In the case of oxidation of organic pollutants occurring in the aqueous medium, cavitation forms the basis of numerous advanced oxidation processes (AOPs). This paper presents the results of investigations on the efficiency of oxidation of the following groups of organic compounds: organosulfur, nitro derivatives of benzene, BTEX, and...
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Introduction to the special issue on machine learning in acoustics
PublicationWhen we started our Call for Papers for a Special Issue on “Machine Learning in Acoustics” in the Journal of the Acoustical Society of America, our ambition was to invite papers in which machine learning was applied to all acoustics areas. They were listed, but not limited to, as follows: • Music and synthesis analysis • Music sentiment analysis • Music perception • Intelligent music recognition • Musical source separation • Singing...
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Excitation of Non-Wave Modes by Sound of Arbitrary Frequency in a Chemically Reacting Gas
PublicationThe nonlinear phenomena in the field of high intensity sound propagating in a gas with a chemical reaction, are considered. A chemical reaction of A → B type is followed by dispersion and attenuation of sound which may be atypical during irreversible thermodynamic processes under some conditions. The first and second order derivatives of heat produced in the chemical reaction evaluated at the equilibrium temperature, density and...
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A Comparison of STI Measured by Direct and Indirect Methods for Interiors Coupled with Sound Reinforcement Systems
PublicationThis paper presents a comparison of STI (Speech Transmission Index) coefficient measurement results carried out by direct and indirect methods. First, acoustic parameters important in the context of public address and sound reinforcement systems are recalled. A measurement methodology is presented that employs various test signals to determine impulse responses. The process of evaluating sound system performance, signals enabling...
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MOŻLIWOŚCI IDENTYFIKACJI STANU TECHNICZNEGO WARSTW ŚLIZGOWYCH ŁOżYSK SILNIKÓW SPALINOWYCH O ZAPŁONIE SAMOCZYNNYM W PRZYPADKU WYKORZYSTANIA EMISji AKUSTYCZNEJ JAKO SYGNAŁU DIAGNOSTYCZNEGO
PublicationW artykule zaprezentowano wyniki badań wielowarstwowych panwi łożysk ślizgowych silników tłokowych. Scharakteryzowano własności obciążeń tego rodzaju panwi oraz ich zużycia szczególnie zmęczeniowego i ściernego. Wykazano przydatność emisji akustycznej jako sygnału diagnostycznego do ujawniania zużycia powłok ślizgowych i zaporowych. Przedstawiono wyniki pomiarów parametrów emisji akustycznej, wykonanych za pomocą 12- kanałowej...
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Kifayat Ullah
PeoplePh.D. Scholar in the department of electrical and control engineering at Gdansk University of Technology, Poland. My research interest includes Electric drives, Power Electronics, and Renewable Energy Resources. I hold My Master of Engineering degree in Electronics and Communications Engineering from the Liaoning University of Technology, China, and a Bachelor's degree in Electrical Engineering from International Islamic University...
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Resilience of 5G Mobile Communication Systems to Massive Disruptions
PublicationThis chapter discusses vital techniques to enhance the resilience of 5G systems. It starts with dependability assessment of 5G networks. Next, it describes (a) the frequency fallback technique to improve availability and survivability of 5G services, (b) segment interleaving scheme to enhance communications resilience between base stations and the remaining part of the network and (c) multi-operator protection to address the resilience...
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Harmony Search for Self-configuration of Fault–Tolerant and Intelligent Grids
PublicationIn this paper, harmony search algorithms have been proposed to self-configuration of fault-tolerant grids for big data processing. Self-configuration of computer grids lies in the fact that new computer nodes are automatically configured by software agents and then integrated into the grid. A base node works due to several configuration parameters that define some aspects of data communications and energy power consumption. We...
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The role of ergonomics in architectonic and marketing operations
PublicationThe 20th century, along with the development of mass culture, brought a rapid increase of marketing communications significance. At first, this branch of art had an informational function associated with advertising operations. Nowadays, an increase of marketing specialists’ interest in influencing a human being by the space they stay in may be observed. Ergonomics plays an important role in such operations. The aim of this article...
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Future research directions in design of reliable communication systems
PublicationIn this position paper on reliable networks, we discuss new trends in the design of reliable communication systems. We focus on a wide range of research directions including protection against software failures as well as failures of communication systems equipment. In particular, we outline future research trends in software failure mitigation, reliability of wireless communications, robust optimization and network design, multilevel...
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IEEE International Conference on Wireless and Mobile Computing, Networking and Communications
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Visual Information Communication and Interaction (Visual Information Communications International)
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Wastewater treatment by means of advanced oxidation processes based on cavitation – A review
PublicationHydrodynamic and acoustic cavitation combined with advanced oxidation processes (AOPs), including, among others, the Fenton process, is a promising alternative to the technologies of wastewater treatment technologies in use today. The present review discusses processes based on cavitation combined with AOPs and evaluates their effectiveness in oxidation of organic contaminants. Complete degradation of, among others, p-nitrotoluene,...
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Mechanizmy bezpieczeństwa transmisji w systemie netBaltic
Publicationartykule zaprezentowano założenia dotyczące zabezpieczania węzłów sieci realizowanej w ramach systemu netBaltic. Ze względu na dużą różnorodność rozważanych mechanizmów komunikacyjnych architektura bezpieczeństwa została podzielona na kilka elementów – infrastrukturę klucza publicznego (PKI), bezpieczeństwo systemowe węzłów, zabezpieczanie komunikacji w modelu samoorganizującej wieloskokowej sieci kratowej, a także sieci niewrażliwej...
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Designing Intelligent Factory: Conceptual Framework and Empirical Validation
PublicationThis paper presents a framework for monitoring, analysing and decision making for a smart manufacturing environment. We maintain that this approach could play a vital role in developing an architecture and implementation of Industry 4.0. The proposed model has features like experience based knowledge representation and semantic analysis of engineering objects and manufacturing process. It is also capable of continuous real time...
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Depolarisation Model for a BAN Indoor Scenario
PublicationIn this paper, an analysis of depolarisation in Body Area Networks for Body-to-Infrastructure communications based on a measurement campaign in the 5.8 GHz band in an indoor environment is performed. Measurements were made with an offbody antenna transmitting linearly polarised signals and dualpolarised receiving antennas carried by the user on the body. A Normal Distribution with a mean of 2.0 dB and a standard deviation of 4.3...
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PHONEME DISTORTION IN PUBLIC ADDRESS SYSTEMS
PublicationThe quality of voice messages in speech reinforcement and public address systems is often poor. The sound engineering projects of such systems take care of sound intensity and possible reverberation phenomena in public space without, however, considering the influence of acoustic interference related to the number and distribution of loudspeakers. This paper presents the results of measurements and numerical simulations of the...
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Analysis of a caustic formed by a spherical reflector: Impact of a caustic on architectural acoustics
PublicationFocusing sound in rooms intended for listening to music or speech is an acoustic defect. Design recommendations provide remedial steps to effectively prevent this. However, there is a category of objects of high historical or architectural value in which the sound focus correction is limited or even abandoned. This also applies to indoor or outdoor concert shells, installations for teaching and acoustic presentations, etc. The...
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Influence of the Widespread Use of Corten Plate on the Acoustics of the European Solidarity Centre Building in Gdansk
PublicationThis paper describes the relationship between a strong architectural vision that is difficult to balance, and user expectations in terms of acoustics. The focus is on the use of corten steel as the dominant finishing material on façades and interiors to achieve an expressive, symbolic message through program-based design. The architectural premises justifying the adopted solutions are presented, especially the universality and...
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Detection of Objects Buried in the Sea Bottom with the Use of Parametric Echosounder
PublicationThe paper contains results of a in situ research main task of which was to detect objects buried, partially or completely, in the sea bottom. Object detecting technologies employing acoustic wave sources based on nonlinear interaction of elastic waves require application of parametric sound sources. Detection of objects buried in the sea bottom with the use of classic hydroacoustic devices such as the sidescan sonar or multibeam...
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Modeling of Combined Phenomena Affecting an AUV Stealth Vehicle
PublicationIn the paper some results of research connected with modelling the basic stealth characteristics of an AUV vehicle are presented. First of all a general approach to design of the stealth AUV autonomous underwater vehicle under consideration is introduced. Then, the AUV stealth vehicle concept is briefly described. Next a method of modelling of the stealth characteristics is briefly described as well. As an example of the stealth...
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Architektura bezpieczeństwa systemu netBaltic
PublicationW artykule zaprezentowano założenia dotyczące zabezpieczania węzłów sieci realizowanej w ramach systemu netBaltic. Ze względu na dużą różnorodność rozważanych mechanizmów komunikacyjnych architektura bezpieczeństwa została podzielona na kilka elementów – infrastrukturę klucza publicznego (PKI), bezpieczeństwo systemowe węzłów, zabezpieczanie komunikacji w modelu samoorganizującej wieloskokowej sieci kratowej, a także sieci niewrażliwej...
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Zastosowanie techniki ściegu odpuszczającego do spawania mokrego
PublicationW artykule przedstawiono zastosowanie techniki ściegu odpuszczającego do poprawy właściwości złączy ze stali konstrukcyjnych wykonywanych w warunkach mokrego spawania pod wodą. Scharakteryzowano spawanie mokre elektrodami otulonymi zmiany struktury i właściwości złączy spawanych przez nakładanie ściegów odpuszczających. Przedstawiono metodykę oraz wyniki badań metalograficznych i twardości próbek ze stali konstrukcyjnej o podwyższonej...
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Jamming and jamming mitigation for selected 5G military scenarios
PublicationThis paper presents jamming and jamming mitigation techniques, which can be used in relation to emerging military systems based on fifth-generation (5G) technology. Nowadays, 5G technology provides incremental improvements over Long Term Evolution (LTE) networks resulting in the enhancement of civilian communications. Considering enormous possible applications of this new technology, it is feasible to use them in military utilities....
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Assessment of User Mobility’s Influence on System Loss in Several Body-to-Body Scenarios
PublicationIn this paper, Body-to-Body communications in indoor and outdoor environments for different on-body antenna configurations and different mobility scenarios were studied, based on system loss measurements at 2.45 GHz. The main objective is to properly characterise the influence of the Transmitter-Receiver configuration on system loss and fast fading behaviour, the latter being modelled by the Rice Distribution. Globally, it is observed...
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Application of BAN Network to Increase Security in Transport Systems
PublicationIn the article general characteristics of the BAN network with M2M communications are presented. These are networks that enable the implementation of wireless transmission of signals using special sensors located on the body or implanted subcutaneously. These sensors allow monitoring of different type life parameters of a human. In the next part of work there is proposed the implementation of BAN networks to transport systems as...
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Ultrawideband transmission in physical channels: a broadband interference view
PublicationThe superposition of multipath components (MPC) of an emitted wave, formed by reflections from limiting surfaces and obstacles in the propagation area, strongly affects communication signals. In the case of modern wideband systems, the effect should be seen as a broadband counterpart of classical interference which is the cause of fading in narrowband systems. This paper shows that in wideband communications, the time- and frequency-domain...
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Fading Analysis in Off-Body Channels in a Straight Metallic Corridor in a Passenger Ferry Environment
PublicationThis paper presents a fading analysis for Body Area Networks off-body communications at 2.45 GHz in a passenger ferry environment. The results are based on measurements performed for dynamic scenarios in a straight metallic corridor. Two components, extracted from instantaneous system loss values, have been analysed: small- and large-scales fading, separately for each scenario. Well-known probability distribution functions have...
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Developing assumptions for the tram noise attenuation passive system using the noise maps analysis method
PublicationThe paper presents experimental research carried out to determine the possible actions to reduce thenoise generated by trams in a highly urbanised area. A few design strategies affecting tram ride qualityhave been presented – especially in the aspect of the acoustic phenomena. Main sources of the noisein trams were characterised. The paper includes selected results of comprehensive...
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Cavitation based cleaner technologies for biodiesel production and processing of hydrocarbon streams: A perspective on key fundamentals, missing process data and economic feasibility – A review
PublicationThe present review emphasizes the role of hydrodynamic cavitation (HC) and acoustic cavitation in clean and green technologies for selected fuels (of hydrocarbon origins such as gasoline, naphtha, diesel, heavy oil, and crude oil) processing applications including biodiesel production. Herein, the role of cavitation reactors, their geometrical parameters, physicochemical properties of liquid media, liquid oxidants, catalyst loading,...
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Detection of the Incoming Sound Direction Employing MEMS Microphones and the DSP
PublicationA 3D acoustic vector sensor based on MEMS microphones and its application to road traffic monitoring is presented in the paper. The sensor is constructed from three pairs of digital MEMS microphones, mounted on the orthogonal axes. Signals obtained from the microphones are used to compute sound intensity vectors in each direction. With this data, it is possible to compute the horizontal and vertical angle of an incoming sound....
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Distributed System For Noise Threat Evaluation Based On Psychoacoustic Measurements
PublicationAn innovative system designed for the continuous monitoring of acoustic climate of urban areas was presentedin the paper. The assessment of environmental threats is performed using online data, acquired through a grid ofengineered monitoring stations collecting comprehensive information about the acoustic climate of urban areas.The grid of proposed devices provides valuable data for the purpose of long and short time acoustic climateanalysis....
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Weldability of high strength steels in wet welding conditions
PublicationIn 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...