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Search results for: UNDERWATER ACOUSTIC CLIMATE
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The Environmental Benefits of Photovoltaic Systems: The Impact on the Environment in the Production of Photovoltaic Systems: With a Focus on Metal Recovery
PublicationGreenhouse gases (GHGs) such as carbon dioxide, nitrous oxide and methane, trap heat and energy, thus preventing solar radiation from escaping back into space. As the quantity of greenhouse gases in the atmosphere increases so does the trapped heat and corresponding global temperature. As a result, storms become more violent, droughts more prevalent, glaciers melt, and sea levels rise, to name but a few effects of a rapidly changing...
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Phytoplankton communities of polar regions–Diversity depending on environmental conditions and chemical anthropopressure
PublicationThe polar regions (Arctic and Antarctic) constitute up to 14% of the biosphere and offer some of the coldest and most arid Earth's environments. Nevertheless several oxygenic phototrophs including some higher plants, mosses, lichens, various algal groups and cyanobacteria, survive that harsh climate and create the base of the trophic relationships in fragile ecosystems of polar environments. Ecosystems in polar regions are characterized...
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Similarities and differences in the production of renewable energy in Central and Eastern Europe countries
PublicationResearch background: In the era of climate change, environmental degradation, but also growing pub-lic awareness, there is a need to look for new ecological energy sources. This condition can be met by renewable energy sources (RES). The EU seeks to have a 32% share of its gross final energy consumption from renewable sources by 2030. While the EU as a whole is on course to meet its...
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Akustyczna analiza parametrów ruchu drogowego z wykorzystaniem informacji o hałasie oraz uczenia maszynowego
PublicationCelem rozprawy było opracowanie akustycznej metody analizy parametrów ruchu drogowego. Zasada działania akustycznej analizy ruchu drogowego zapewnia pasywną metodę monitorowania natężenia ruchu. W pracy przedstawiono wybrane metody uczenia maszynowego w kontekście analizy dźwięku (ang.Machine Hearing). Przedstawiono metodologię klasyfikacji zdarzeń w ruchu drogowym z wykorzystaniem uczenia maszynowego. Przybliżono podstawowe...
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Modelowanie systemów energetycznych wytwarzania energii elektrycznej i ciepła do celów planowania rozwoju - wybrane zagadnienia
PublicationSystemy energetyczne wymagają przemian technologicznych w kierunku neutralności klimatycznej. W Polsce, w której systemie elektroenergetycznym i systemach ciepłowniczych dominują przestarzałe elektrownie i ciepłownie węglowe, dążenie do minimalizacji wpływu na środowisko wiąże się z wysokimi kosztami. Dlatego należy szukać optymalnych ścieżek roz-woju energetyki, aby osiągnąć ambitne długoterminowe cele strategiczne, przy minimalizacji...
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THE INFLUENCE OF THE URBAN DESIGN ON THE AIR EXCHANGE IN CITIES. SELECTED PROBLEMS IN POLISH REALITY
PublicationThe progress of the architecture and urbanism raises problems requiring interdisciplinary research conducted with the use of advanced experimental techniques and computer simulation. The fields of this research include aerodynamics, especially in intensively developed area of Environmental Wind Engineering (EWE). Aerodynamic phenomena occurring around buildings have a significant impact on the quality of the climate in the cities....
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The accuracy of a new approach to order determination for the Modified Prony method in swath mapping application
PublicationThis article presents the performance of a new approach to determine the model order for the modified Prony method applied to swath acoustic mapping. Key requirements for any mapping application are depth determination accuracy and angular resolution. Depth determination accuracy is strictly related to angular accuracy and geometrical relations between receiver and sources of the backscattered signal. Angular resolution determines...
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Zmienność termicznego charakteru okresów zimowych w Polsce i jej przyczyny
PublicationPraca przybliża problematykę funkcjonowania fenomenu klimatycznego Oscylacji Północnego Atlantyku (Norh Atlantic Oscillation – NAO) oraz omawia jej wpływ na kształtowanie charakteru termicznego zim (grudzień – marzec) na obszarze Polski. Zmiana faz NAO z w przewadze ujemnych na w przewadze dodatnie, jaka nastąpiła w latach 1987-1989 spowodowała, że po roku 1989 obserwuje się w Polsce znaczne złagodzenie stopnia ostrości zim.
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AKUSTYCZNY ASPEKT ZASTOSOWANIA BLACHY KORTENOWEJ W EUROPEJSKIM CENTRUM SOLIDARNOŚCI W GDAŃSKU
PublicationArtykuł opisuje użycie blachy kortenowej jako dominującego materiału wykończeniowego na elewacjach i we wnętrzach budynku o przesłaniu symbolicznym. Przedstawiono architektoniczne przesłanki, uzasadniające jednorodność zastosowanego materiału. Na tym tle omówiono wpływ blachy kortenowej na akusty-kę pomieszczeń, wraz z podaniem kroków zaradczych redukujących nadmierną pogłosowość i zwiększających stopień rozproszenia dźwięku. Pozytywnym...
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NEW DESIGNS OF CENTRIFUGAL MAGNETIC FLUID SEALS FOR ROTATING SHAFTS IN MARINE TECHNOLOGY
PublicationThe centrifugal magnetic fluid seals have important advantage over the conventional centrifugal seals. They maintain very good sealing capacity at static, medium and high speeds of shaft rotation, with the increased seal lifetime, and minimum torque and static friction. These seals are particularly useful in cases when the angular shaft velocity varies and sometimes decreases to nearly or exactly zero, such as in flywheel applications,...
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Searching of the buried objects in the sea bottom by means of noninvasive methods
PublicationSearching of objects on the seabed or under its surface currently is a challenge for a number of researchers interested in the sea bottom. The problem relates to the objects on the depths of up to several tens of meters from the surface of the seabed. Finding the objects is the subject of interest for a wide group of users starting from archaeologists, and ending on groups interested in marine safety, as well as in military application...
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System for characterisation and multidimensional imaging of seafloor using multibeam sonar data
PublicationMultibeam sonars are widely used in applications like high resolution bathymetry measurements, underwater object detection and imaging, etc. Also, they are the promising tool in seafloor characterisation and classification, having several advantages over conventional single beam echosounders. The proposed approach to seafloor classification relies on the combined use of three different techniques. In each of them, a set of descriptors...
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An Intergrated Model of Motion, Steering, Positioning and Stabilization of an Unmanned Autonomous Maritime Vehicle
PublicationIn the paper the aim of an interdisciplinary research is presented. The research method is introduced. An object the unmanned autonomous maritime vehicle is briefly described. The key research problem concerns a combined model of the vehicle motion including the loads of lift and hydrodynamic nature. The model takes into account the gravity and displacement forces, resistance and thrust forces, lift and other hydrodynamic forces....
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Integrated spatial and energy planning – importance of a problem for contemporary architects and urban planners with focus on environmental factors
PublicationAlong with respecting basic sustainable development goals, planners will also be obliged to meet more stringent provisions related to energy efficiency in the coming years. In Poland, a crucial year will be 2021, when the EU directive on the energy efficiency of buildings comes into force. In this matter, not only the characteristics of individual objects are of great importance, but their whole complexes and the overall approach...
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Computer-Aided Automated Greenery Design—Towards a Green BIM
PublicationContemporary climate challenges are changing the architect’s awareness, which results in a broader spectrum of interest. The available software enables the design of vegetation, but it is often very limited and requires specialist knowledge. The available software allows the creation of individual solutions based on visual algorithms or writing scripts; however, they are still not common methods used in architecture and urban planning....
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Long-Term GNSS Tropospheric Parameters for the Tropics (2001-2018) Derived from Selected IGS Stations
PublicationThis paper describes dataset “Tropospheric parameters derived from selected IGS stations in the tropics for the years 2001-2018” contains GNSS-derived zenith tropospheric delay (ZTD), a posteriori corrected zenith wet delay (ZWD), and precipitable water vapour (PWV) time series. These troposphere-related data were estimated for the Jan 2001 – Dec 2018 period for 43 International GNSS Service (IGS) stations located across the global...
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Noise emitted by SKM Trains in Gdansk
PublicationHigh intensity traffic of SKM trains in Gdansk carries a significant level of noise emission. SKM line runs through the central part of the city and therefore in the vicinity of residential areas and recreational facilities. This research was planned and performed to find out what was the real noise emission of SKM trains and to determine whether the measurement noise values are within allowed limits. Individual acoustic events...
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An adaptive approach to non-destructive evaluation (NDE) of cast irons containing precipitated graphite particles with the help of magnetoacoustic emission
PublicationPhysical properties of cast irons strongly depend on both their microstructure and the presence of casting defects. The paper analyses the possibility of application of magnetoacoustic emission (MAE) for nondestructive detection of flawed cast iron components. The investigated samples containing dross, chunky graphite and lamellar graphite were compared with the reference, flawless, spheroidal cast iron sample. The optimisation...
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CPLFD-GDPT5: High-resolution gridded daily precipitation and temperature data set for two largest Polish river basins
PublicationThe CHASE-PL (Climate change impact assessment for selected sectors in Poland) Forcing Data–Gridded Daily Precipitation & Temperature Dataset–5 km (CPLFD-GDPT5) consists of 1951–2013 daily minimum and maximum air temperatures and precipitation totals interpolated onto a 5 km grid based on daily meteorological observations from the Institute of Meteorology and Water Management (IMGW-PIB; Polish stations), Deutscher Wetterdienst...
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Technological solutions to landfill management: Towards recovery of biomethane and carbon neutrality
PublicationInadequate landfill management poses risks to the environment and human health, necessitating action. Poorly designed and operated landfills release harmful gases, contaminate water, and deplete resources. Aligning landfill management with the Sustainable Development Goals (SDGs) reveals its crucial role in achieving various targets. Urgent transformation of landfill practices is necessary to address challenges like climate change,...
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Badanie wierności brzmienia dźwięku instrumentów wirtualnych VST/TRTAS
PublicationTematem referatu jest subiektywne badanie wierności brzmienia instrumentów wirtualnych (VST/TRTAS) wykorzystujących próbkowanie dźwięków rzeczywistych instrumentów muzycznych. Na potrzeby przedstawionej pracy wybrano kilka utworów muzyki orkiestrowej z epoki romantyzmu i klasycyzmu, nagranych przy użyciu instrumentów akustycznych. Następnie zaaranżowano fragmenty tych utworów, wykorzystując do tego instrumenty wirtualne i efekty...
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EMISJA AKUSTYCZNA JAKO SYGNAŁ DIAGNOSTYCZNY ODWZOROWUJĄCY ZMĘCZENIOWE ZUŻYCIE WARSTW ŚLIZGOWYCH PANWI ŁOŻYSK GŁÓWNYCH I KORBOWYCH SILNIKÓW O ZAPŁONIE SAMOCZYNNYM
PublicationW artykule przedstawiono wyniki badań laboratoryjnych, z których wynika, że emisja akustyczna (EA) może być uznana za sygnał diagnostyczny, przydatny do identyfikacji stanu technicznego łożysk głównych i korbowych okrętowych silników o zapłonie samoczynnym. Wykazano w nim bowiem, że parametry emisji akustycznej takie jak: czas rejestracji, energia sygnału, amplituda sygnału, ilość przekroczeń poziomu dyskryminacji, czas narastania,...
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Ruch wirowy wywoływany przez ultradźwięk w płynach z relaksacją
PublicationRozprawa doktorska poświęcona jest badaniu ruchu wirowego wywoływanego przez ultradźwięk w różnych modelach płynów z relaksacją. Ma ona charakter teoretyczny, jednak wykorzystanie uzyskanych dzięki niej wyników może przynieść lepsze zrozumienie ruchu wirowego wywoływanego przez siłę akustyczną. W I rozdziale rozprawy przedstawione zostały ogólne rozważania dotyczące akustyki nieliniowej. Rozdział II dotyczy ruchu wirowego wywoływanego...
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Charakterystyka hydrogeochemiczna wód podziemnych rejonu Przylądka Rozewie na podstawie badań ich naturalnych wypływów
PublicationW niniejszym artykule zostały przedstawione wyniki badań, które były prowadzone w strefie brzegowej rejonu Przylądka Rozewie. Prowadzone w latach 2013-2014 badania miały charakter monitoringu podstawowych właściwości fizykochemicznych oraz oznaczenia składu jonowego wód wypływających ze zbocza w obrębie badanego terenu. Warunki hydrogeochemiczne rejonu Przylądka Rozewie są kształtowane pod wpływem specyficznego nadmorskiego klimatu,...
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Multimedia services applied to noise and hearing monitoring and measuring
PublicationThe goal of this chapter is to show a research study related to processing of data acquired by the multimedia services engineered at the multimedia systems department (MSD) of the Gdansk University of Technology. This concerns a survey on noise threat employing the multimedia noise monitoring system (MNMS) and hearing tests performed by the "I can hear. . . " system. The obtained results of the noise measurements revealed that...
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Status and trends of mercury pollution of the atmosphere and terrestrial ecosystems in Poland
PublicationThe goal of this paper is to assess the current status and trends of total mercury (THg) contamination of the atmosphere and terrestrial ecosystems in Poland. The study shows that the reduced domestic and worldwide atmospheric emission of Hg resulted in decreased THg level in the terrestrial biotope and biosphere. Considering that Poland is one of the main Hg emitters in Europe, the THg concentrations in its abiotic environment...
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Scenario-planning solutions for waterfront flood-prone areas
PublicationThe aim of this article is to discuss the potential of applying scenario planning to achieve resilient and future-oriented solutions for flood-prone areas. The authors have proposed additions to scenario-planning processes based on the introduction of research-by-design architectural inquiries. Examined in this article is the insight into the testing of such a modified scenario-planning methodology during two courses that accompanied...
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Correlation between chemical composition and the presence of selected groups of bacteria in freshwater samples collected from Isfjorden and Billefjorde
PublicationThe average concentrations of pollutants in the arctic water, snow and the atmosphere are much lower than those observed in the temperate climate. Specific conditions occurring in the polar regions have apotential to accumulate the pollutants transported from other parts of the world. In this study, attempts were made to find a correlation between selected chemical components and the bacterial population. The analysis involved...
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Bridging the Gap Between Legitimacy and Neutralisation Strategies in Sustainability Reporting
PublicationAmid global sustainability challenges, such as climate change, companies operating in different industries face increasing demands for accountability and transparency. To meet these demands, sustainability reporting (SR) has become a mainstream business practice in communicating companies’ positive and negative sustainability impacts. This short paper aims to increase our understanding of how companies may release negative information...
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Application of dynamic time warping and cepstrograms to text-dependent speaker verification
PublicationThis work provides a description of an automatic speaker verification (ASV) system. In particular, it documents the evolution of all individual stages of the proposed ASV system design from the phase of preprocessing to an operational decision making system. The aim of this research was to achieve the system of the best safety and ease of use in view of users. The objective estimation of this target has been accomplished by assessing...
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Unusual streaming in chemically reacting gases
PublicationNonlinear stimulation of the vorticity mode caused by losses in the momentum of sound in the chemically reacting gas, is considered. The instantaneous dynamic equation which describes the nonlinear generation of the vorticity mode, is derived. It includes a quadratic nonlinear acoustic source. Both periodic and aperiodic sound may be considered as the origin of the vorticity flow. In the non-equilibrium regime of the chemical reaction,...
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Application of TMS320c67xx signal processors for SONIC-self-optimizing narrowband interference canceler
PublicationThe paper presents a laboratory system for testing active control algorithms of acoustics noise in ducts. An applied algorithm - self-optimizing narrowband interference canceller (SONIC), allows one to remove narrowband disturbances of constant or slowly time-varying frequencies. Example experimental results of using the laboratory system for supression of sinusoidal disturbance are described. An electronic part of the system was...
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Standing Waves in One-Dimensional Resonator Contaning an Ideal Isothermal Gas Affected by the Constant Mass Force
PublicationThe study is devoted to standing acoustic waves in one-dimensional planar resonator which containing an ideal gas. A gas is affected by the constant mass force. Two types of physically justified boundary conditions are considered: zero velocity or zero excess pressure at both boundaries. The variety of nodal and antinodal points is determined. The conclusion is that the nodes of pressure and antinodes of velocity do not longer...
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On the Nonlinear Effects of Magnetoacoustic Perturbations in a Perfectly Conducting Viscous and Thermoconducting Gas
PublicationNonlinear effects of planar and quasi-planar magnetosound perturbations are discussed. The plasma is as- sumed to be a Newtonian thermoconducting gas with infinite electrical conductivity permeated by a magnetic field orthogonal to the trajectories of gas particles. Generation of the non-wave modes (magnetoacoustic heating and streaming) in the field of periodic and aperiodic magnetoacoustic perturbations is discussed. The results...
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Personal adaptive tuning of mobile computer audio
PublicationAn integrated methodology for enhancing audio quality in mobile computers is presented. The key features are adaptation of the characteristics of the acoustic track to the changing conditions and to the user's individual preferences. Original signal processing algorithms are introduced, which concern: linearization of frequency response, dialogue intelligibility enhancement and dynamics processing tuned up to the user's preferences....
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APPLICATION OF THE HIGH FREQUENCY LINEARIZATION OF THE EAR IN PATIENTS WITH TINNITUS . Metoda linearyzacji narządu słuchu u osób cierpiących z szumami usznymi
PublicationThis paper summarises the problem of tinnitus, hypotheses on its causes and the treatment methods. Moreover, a hypothesis on tinnitus origins is explained, based on the mechanisms of the analog-to-digital conversion and quantization. In addition, this paper describes methods of determining the acoustic intensity and spectra of low- level ultrasonic signals, as well as impedance characteristics of an ultrasound transducer. Furthermore,...
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Noise effect on parameters of quiet sonar with code modulation
PublicationEarlier publications of the paper authors have shown that the use of code keying mixed with the CW FM sound signal allows the significant reduction in the distance measurement error, compared to classic silent CW FM sonar. In addition to the code modulation parameters, the magnitude of this error is influenced by the received input acoustic noise. The article shows the dependence of the input signal-to-noise ratio and the sound...
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TIRE/ROAD NOISE AND TIRE ROLLING RESISTANCE ON PROTOTYPE PERS SURFACE
PublicationPoroelastic road surfaces are characterized by low noise of tires running on them.Road pavements of this type are promising solution to problems related to traffic noise in cities and on rural roads. Some technical problems still have to be solved, in particular regarding durability and skid resistance on wet surface. Ongoing and planned works are to contribute to create a quiet, durable and safe road surface, which will become...
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Influence of Natural Conditions on the Imaging of the Bottom of the Gdańsk Bay by Means of the Side Scan Sonar
PublicationThe interest in underwater resources is the reason for the development of modern hydroacoustic systems, including side sonars, which find numerous applications such as: research of seabed morphology and sediment characteristics, preparation of sea sediment maps, and even in special cases of biocenoses such as sea grass meadows, detection of specific targets at the bottom such as shipwrecks, mines, identification of suitable sites...
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Mathemathical model of radial passive magnetic bearing
PublicationIn the article mathematical radial model of passive magnetic bearings to ocean engineering units has been presented. The units application in underwater thrusters should increase propulsion systems durability and gives lower maintenance costs. The rotor of electric motor is hanging in magnetic field taken from radial passive magnetic bearings. However axial direction maintenance must be controlled with electromagnets and their...
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Web-based 3D processing and dissemination of multibeam sonar data
PublicationThe continuous detailed surveys of the various water bodies over time produce a large and ever-increasing volume and density of underwater sounding data. Three-dimensional data, such as those obtained by multibeam sonar systems, are quite complex to manage, and thus their growing numbers increase the pressure on development of new solutions dedicated to processing them. This paper presents a concept system for web-based dissemination...
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Kompetencje członków zespołu wirtualnego
PublicationArtykuł dotyczy problematyki wirtualnej współpracy, która wymaga od osób tworzących zespół oraz od lidera zespołu szczególnych kompetencji. Skoncentrowano się na wiedzy, cechach i umiejętnościach członków zespołu wirtualnego, które są konieczne, by efektywnie realizowali oni założone cele, kreując jednocześnie relacje oparte na wzajemnym zaufaniu. Artykuł zawiera przegląd literatury dotyczącej kompetencji członków zespołu wirtualnego...
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Wpływ właściwości czynników chłodniczych na straty egzergii w pompie ciepła (Influence of Refrigerants Properties for Exergy Losses in Heat Pump)
PublicationArtykuł poświęcony jest wpływowi występujących w pompie ciepła strat egzergii na jej efektywność energetyczną, a co za tym idzie koszty funkcjonowania instalacji. Autorzy prezentują tu metodologię obliczeniową, która może być zastosowana w procesach projektowania układów cieplno-przepływowych. Obliczenia zostały wykonane na podstawie typowego układu powietrznej pompy ciepła pracującej w klimacie środkowo-europejskim. Ponadto w...
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Nowe czynniki chłodnicze i zmiany w instalacjach chłodniczych. Cz.2
PublicationW drugiej części artykułu kontynuowany jest temat związany z ograniczeniami stosowania syntetycznych czynników chłodniczych. W części pierwszej przedstawiono tendencje do zastępowania wycofywanych substancji czynnikami naturalnymi. Niniejszy artykuł traktuje natomiast o możliwości wykorzystywania nowych, syntetycznych czynników z grupy HFO, będących substancjami bezpiecznymi dla środowiska naturalnego, w kontekście ich wpływu na...
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Znaczenie różnorodności w wirtualnej współpracy
PublicationRóżnorodność jest jedną z podstawowych cech zespołów wirtualnych. Odnosi się ona do geograficznego rozproszenia członków zespołu, różnic stref czasowych, w których pracują, zróżnicowania narodowogo i kulturowego, ale również do pracy dla różnych organizacji, pełnienia różnych ról zespołowych o odpowiedzialności za różne części realizowanego projektu. Artykuł dotyczy najważniejszych wymiarów różnorodności istotnych dla wirtualnej...
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Spatial Heterogeneity Impacts of Bilateral Foreign Direct Investment on Green Energy Efficiency in China
PublicationAt present, green energy transformation and climate policy are increasingly connected. The need to improve national competitiveness and implement climate and energy strategies means that an energy-consuming country like China must rapidly enhance its green energy efficiency (GEE) and energy consumption structure. The following paper contributes to the existing literature by analyzing the effects of bilateral FDI on GEE from...
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Suspended-sediment transport related to ice-cover conditions during cold and warm winters, Toudaoguai stretch of the Yellow River, Inner Mongolia, China
PublicationThe presence of winter ice in cold regions changes the water level, flow rate, velocity distribution, and other parameters of the river, which in turn affects the sediment concentration and channel evolution. Based on data obtained from Toudaoguai Hydrological Station from 1959 to 2021, this study examines the characteristics of the ice regime during cold and warm winters and the water and sediment transport processes along the...
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Communication Platform for Evaluation of Transmitted Speech Quality
PublicationA voice communication system designed and implemented is described. The purpose of the presented platform was to enable a series of experiments related to the quality assessment of algorithms used in the coding and transmitting of speech. The system is equipped with tools for recording signals at each stage of processing, making it possible to subject them to subjective assessments by listening tests or, objective evaluation employing...
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Przegląd metod pomiaru temperatury przewodów linii napowietrznych wysokiego napięcia
PublicationW artykule przedstawiono przegląd metod pomiaru temperatury napowietrznych linii wysokiego napięcia stosowanych w celu poprawy niezawodności eksploatacji i w celu wyznaczania dopuszczalnej obciążalności linii. Omówiono system DOL dynamicznej obciążalności linii oraz bezdotykowe metody pomiaru temperatury: pomiar z użyciem pasywnych czujników SAW (ang. Surface acoustic wave sensor), DTS (distributed temperature sensing) z wykorzystaniem...
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Observing its long-term effects on a short-term, multi-day evaluation of the effectiveness of hearing aid use
PublicationThe main objective of the research study was to develop a method for evaluating the effectiveness of hearing protection with hearing aids tailored to the needs and prevailing conditions in the acoustic environments where the elderly most often reside. The method was also intended to estimate the benefits of hearing aids and allow prediction of such an effect based on a short-term trial. It is noteworthy that a short-term evaluation...