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Coupledfield modelling of interferometric hydrophone with self supportedmandrel.
PublikacjaW pracy przedstawiono nowatorską konstrukcję światłowodowego interferometrycznego przetwornika ciśnienia do zastosowań w hydrofonach. Przetwornik ten składa się z cewki światłowodowej zalanej w żywicy epoksydowej. Zaprezentowano technikę modelowania właściwości przetwornika, wykorzystującą opis przy pomocy parametrów równoważnego materiału ortotropowego i Metodę Elementów Skończonych. Przestawiono wyniki statycznego modelowania...
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The shallow sea experiment with usage of linear hydrophone array
PublikacjaPurpose 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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Comprehensive modeling of interferometric hydrophone with self-supported mandrel transducer.
PublikacjaW pracy przedstawiono wyniki modelowania nowego typu samonośnego przetwornika dla interferometrycznego hydrofonu światłowodowego. Zaprezentowano wyniki analizy statycznej, modowej i dynamicznej przeprowadzonej przy pomocy Metody Elementów Skończonych. W modelowaniu wykorzyastano techniki opracowane dla laminatów, co pozwoliło na uzyskanie dokładnych wyników przy względnie krótkim czasie obliczeń.
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Landfill leachate treatment at a pilot plant using hydrophyte systems
PublikacjaConstructed wetlands can provide an effective and economical solution to landfill leachate treatment. In the article the performance of a CW for leachate treatment, consisting of two horizontal flow constructed wetlands (HF-CW) beds, working at the municipal landfill in Gdansk-Szadolki in the period 2004-2005 is being discussed. The plant has been operating since 2001. Clogging problems and surface flow occurred in the system...
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Polyglycerol esters of lauric acid with defined hydrophile-lipophile properties.
PublikacjaZsyntetyzowano estrowe pochodne poligliceroli i kwasu laurynowego w obecności laurynianu sodu powstającego in situ. Przeanalizowano wpływ temperatury, stężenia katalizatora oraz czasu reakcji na postęp reakcji polimeryzacji glicerolu, a także wpływ stężenia karboksylanu i czasu reakcji na reakcję estryfikacji uzyskanej mieszaniny polioli kwasem laurynowym. Zauważono, że zastosowana metoda syntezy estrów poligliceroli prowadzi do...
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Reject water and landfil leachate treatment with hydrophyte method - preliminary results
PublikacjaTreatment of landfill leachate (LL) and reject water (RWC) from dewatering of digested sludge in WWTPs have become one of the actual problems. Treatment of both types of wastewater is in many cases very costly and difficult due to quality and quantity fluctuations in time as well as high concentrations of specific pollutants. In case of our investigation the TSS concentration in RWC was two times higher than in LL. The shere of...
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Pollutants removal effectiveness in hydrophyte filters with sequential vertical and horizontal flow
PublikacjaThe object of investigations was the constructed wetland in Wiedersberg in Saxonia in Germany supplied with domestic sewage from 145 inhabitants. The biological part was composed of sequential reed beds with vertical and horizontal flow of sewage. It in one of new solutions, because up till now configuration with vertical bed situated at front of biological part of treatment was applied.The evaluation of object performance was...
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Impact of Spatial Noise Correlation on Bearing Accuracy in DIFAR Systems
PublikacjaDIFAR type underwater passive systems are one of the more commonly used tools for detecting submarines. At the design stage, which usually uses computer simulations, it is necessary to generate acoustic noise of the sea. It has been shown that correlating noise significantly reduces these errors compared to the assumption that noise is uncorrelated. In addition, bearing errors have been shown to be the same in systems with a commonly...
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Modeling of performance of a AUV vehicle towards limiting the hydro-acoustic field.
PublikacjaSome results of research devoted to the modeling of a AUV-Stealth vehicle performance towards limiting its hydro-acoustic field are presented in the paper. At the beginning the AUV-Stealth autonomous underwater vehicle concept is described. Then the method of research is introduced. Next the key design drivers of the AUV-Stealth vehicle are presented. Between them are the AUV-Stealth hull form, arrangement of internal spaces,...
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Underwater Navigation Ssystem Based on Doppler Shift – Measurements and Error Estimations
PublikacjaA new acoustic navigation system was developed to determine the position and speed of moving underwater objects such as divers and underwater vehicles. The path of an object and its speed were determined by the Doppler shifts of acoustic signals emitted by a transmitter placed on the object and received by four hydrophones installed at the periphery of the monitored body of water. The position and speed measurements were affected...
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Experiment with small objects floating under water in the harbor security aspect.
PublikacjaObservation of the underwater area is the element of general trend which primary purpose is to protect and enhance the safety of the selected region. The aim of the paper is to present the acoustic characteristics of typical objects floating on the surface or under the water, which constitute some knowledge on how to detect these objects. Create a catalog of acoustic signatures and acoustic images of objects mostly floating under...
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The Doppler effect in a bistatic system for determining the position of moving targets
PublikacjaThe article presents the theoretical analysis and the results of numerical calculations of the Doppler effect it occurs in a system designed to determine the position and speed of a moving target. The transmitter is the source of the signal and it emits a sinusoidal, acoustic and continuous wave. Signal reflected off a moving target is received by four hydrophones. Based on the signals, four Doppler shifts are determined and inserted...
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Underwater Navigation System Based on Doppler Shifts of a Continuous Wave
PublikacjaThe paper describes a concept of an underwater navigation system designed to determine the location and speed of its ROVs or divers. Conducted by the Department of Marine Electronic Systems at the Gdansk University of Technology for several years, research has focused on navigation systems which determine positions on the basis of Doppler shifts of echo signals reflected from a moving object. This article presents a different version...
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Receiver of Doppler multistatic system for moving target detection and tracking
PublikacjaThe article presents a method for solving major structural problems that occur in the receiver used in the multistatic Doppler system, aimed at determination of the trajectory and velocity of a moving target. In the system two transmitters emit acoustic continuous sinusoidal waves at different frequencies. The signals, scattered from a moving target are received by four hydrophones. Beside of the echoes, much larger signals coming...
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The efficiency of pollutants removal and concepts on improvement for single-family TWs
PublikacjaIn the rural areas building of sewerage systems and central wastewater treatment plants (WWTPs) often brings too high costs, due to high distances from one farm to another and terrain configuration. Individual treatment systems for each farm are a good solution. Theteratment wetlands for nine individual farms were constructed in Kaszubian Lake District in summer and autumn 2009. Three configurations of hydrophyte beds were chosen....
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Laboratory investigation with subbottom parametric echosounder SES-2000 standard with an emphasis on reflected pure signals analysis
PublikacjaThe main goal of the paper is to describe correlations between measurements results of trials taken on Gulf of Gdańsk bottom sounded with parametric echosounder SES-2000 Standard and laboratory research where collected during survey sediments were measured. Stationary tests took place at Gdansk University of Technology where 30 meters long 1.8 meter deep and 3 meters wide water tank is located. Main lobe of antenna was directed...
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Morphology of bio-based polyurethane composites filled by mer-cerized or silanized natural fibres
PublikacjaBio-composites are materials which possess unique properties and undergo biodegra-dation under specific conditions. Bio-composites belong to the group of materials produced with the use of renewable raw materials. They contain reinforcement, mainly in the form of natural fiber, which has high stiffness and resistance; filler powders are less frequently used. Significant features of natural fibers are elongation, density, thermal...
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Spetiation of organic matter in Vertical Flow Constructed Wetlands
PublikacjaThe object of the research were VFCWs which are a component of biological treatment of two hybrid hydrophyte systems located in Wieszyno and Wiklino, close to Słupsk, Poland. The facilities that are subject to analyses are unified in terms of structure (filtration material, depth of the bed and time of operation), but they differ in organic matter load, amounting respectively to: 8.0 gCOD/m2day and 31.0 gCOD/m2day.The intensity...
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The concept of sewage-sludge management system for an individual household
PublikacjaThe individual farms at the rural areas often face problems with domestic sewage collection and treatment. In many cases building of sewerage systems and central wastewater treatment plants (WWTPs) brings too high costs, due to high distances from one farm to another and terrain configuration. Treatment wetlands for individual farms can solve this problem. In the article, an overview of individual treatment wetlands in Europe and...
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Multistatyczny, Dopplerowski System określania położenia i prędkości ruchomych celów w wodzie
PublikacjaW omawianym w pracy multistatycznym, dopplerowskim systemie określania położenia i prędkości ruchomych celów w wodzie źródłem sygnału są dwa nadajniki emitujące sinusoidalne, akustyczne fale ciągłe o różnych częstotliwościach, które po odbiciu od ruchomego celu są obierane przez cztery hydrofony. W artykule przedstawiono analize teoretyczna efektu Dopplera, na którym oparte jest działanie systemu oraz metodę rozwiązania głównych...
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One-Step Synthesis of W/O and O/W Emulsifiers in the Presence of Surface Active Agents
PublikacjaThe main goal of this study was to describe the method of the synthesis of the dodecyl-, tetradecyl-, hexadecyl- and octadecyl-propylene glycol emulsifiers in the presence of selected anionic and nonionic surfactants. Acyl propylene glycol emulsifiers were produced by esterification of propane-1,2-diol (propylene glycol, PG) with C12:0-C18:0 fatty acids in the presence of anionic sodium dodecyl sulfate (SDS) and nonionic-poly(ethylene...