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Low and high energy explosive materials used in shale gas recovery
PublicationNowadays the explosives are widely used in many areas of life, including industry and mining. A wide range of explosive materials is used in the petroleum industry - from low to high explosives. Recently, as the unconventional oil and gas production became possible, explosives are also found to be used in perforators during the pre-completion stage of the fracturing process. This paper presents literature on theoretical and practical...
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Experimental tests of reinforced concrete deep-beams
PublicationThe paper presents results of experimental research of the reinforced concrete deep beam with a spatial arrangement. Tested structural elements consist of the cantilever deep beam loaded on the height and transverse deep beam with hanging on it another one. The analysis includes crack morphology, effort of steel and load distribution. The article verified effectiveness of two different kind of reinforcement in both tested deep...
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Politiceskaja pressa o rosijsko-ukrainskich otnoszenijach i sobytiach w Krymu = Polish press covering russian- ukrainian relations and events in Crimea
PublicationThe paper made a review of opinions expressed by the most widely read Polish newpapers on the issue of Ukraine-Russian relations and events in Crimea in the period from early December 2013 till late March 2014. The author has brought to light attitudes to the events in Ukraine perceived while having in mind preserving security of Poland in political, economic and societal aspects. The EC policy towards the Russian Federation and...
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Performance analysis of co-existing Wi-Fi and Bluetooth networks
PublicationPasmo ISM wykorzystywane jest przez wiele różnych technologii transmisji bezprzewodowej. Tym samym pojawiają się problemy związane z zapewnieniem określonej efektywności dla sieci różnych technologii. W artykule analizowano wpływ wzajemnych interferencji nadajników sieci Bluetooth i IEEE802.11b, badano przykładowe scenariusze pracy oraz przedstawiono wyniki badań dotyczących techniki AFH (ang. Adaptive Frequency Hopping).
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Prediction of Weld Deformations by Numerical Methods - Review
PublicationThe welding process is the basic technique of joining in the shipbuilding industry. This method generates welding distortions that cause a lot of problems during the manufacturing process due to both the time and cost of straightening as well as their influence on later stages of production. Proper preparation of welding processes plays a growing role in the shipbuilding industry and the development of calculating tools is being...
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Towards 5G — Cloud-based Radio Access Networks
PublicationIn the paper a general concept of the 5G network architecture is presented as well as system requirements having impact on innovative solutions in the 5G network are highlighted. A major part of the paper is both presentation and discussion of the problem of Cloud Radio Access Network introduction for public networks in which the cell and resource virtualisation will be implemented. On the other hand, the problem of resource virtualization...
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Gender, education and motivation of onwers of small firms and their growth
PublicationAlmost every article on the growht of SMEs begins with noting the lack of a unified theory or a model of growth in thei group of companies, although the growth of small and medium sized enterprises has been the subject of research for many years and early theories about it appeared already before the Second World War. In the paper some conlusions about the relation between gender, education and motivation of owner and the small...
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Performance Measurements of Real Time Video Transmission from Car Patrol
PublicationThe HSUPA technology application to video streaming from moving vehicle to the central server is presented in the paper. A dedicated software for transmission control in case of non public IP address is employed. Quality of video streaming in urban area was measured. Several car routes were investigated in the area of the Polish Tricity. Measurements pointed out that the real time streaming quality during vehicle movement is sufficient...
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Predicting the critical micelle concentration of aqueous solutions of ionic liquids and other ionic surfactants
PublicationNiektóre ciecze jonowe, szczególnie te będące kombinacją organicznego i nieorganicznego jonu, wykazują strukturalne podobieństwo do surfaktantów. Krytyczne stężenie micelizacji jest podstawowym parametrem w chemii powierzchni i nauce o koloidach. Parametr ten został zmierzony dla wielu cieczy jonowych, jednakże ze względu na ogromną ilość możliwych kombinacji anionów i kationów jego eksperymentalny pomiar dla wszystkich struktur...
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Possible quadrupole-order-driven commensurate-incommensurate phase transition in B20 CoGe
PublicationThe B20-type cobalt germanide CoGe was investigated by measuring the specific heat, resistivity, and 59Co nuclear magnetic resonance (NMR).We observed a phase transition at TQ = 13.7 K, evidenced by a very narrow peak of the specific heat and sharp changes of the nuclear spin-spin (T −1 2 ) and spin-lattice (T −1 1 ) relaxation rates. The fact that the entropy release is extremely small and the Knight shift is almost independent...
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Trudności ochrony środowiska w planowaniu przestrzennym–struktura problemu
PublicationArtykuł zawiera ogólną systematykę negatywnych oddziaływań na środowisko przyrodnicze. Autor omawia trudności zapobiegania przez planowanie przestrzenne zagrożeniom środowiska. Analizuje strukturę problemu, wskazując czynniki: społeczne, gospodarcze, prawne i polityczne, w tym rolę: motywacji, hierarchii wartości, świadomości ekologicznej, przekonań. Autor wskazuje też działania prowadzące do ograniczenia zagrożeń.
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Badawczo-rozwojowe laboratorium sieci optycznych wykorzystujące sprzęt ADVA Optical Networking
PublicationPrzedstawiono uwarunkowania i kierunki zmian w sieciach optycznych, a następnie wskazano na potrzebę posiadania laboratorium, w którym możliwe byłoby prowadzenie prac badawczo-rozwojowych oraz kształcenie. Przedstawiono koncepcję takiej sieci opartej na sprzęcie ADVA Optical Networking zrealizowaną w Katedrze Sieci Teleinformacyjnych Wydziału ETI PG. Opisano możliwości sprzętowo-funkcjonalne tego laboratorium oraz prowadzone prace...
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Computer-aided Analysis of Induced Sheath Voltages in High Voltage Power Cable System
PublicationThis paper concerns the effect of configuration of high voltage power cables on induced voltages in their metallic sheaths. One, two or three cables per phase and phase sequence of the cables are considered. Computing of the voltages was performed for a normal operation and in case of earth fault. Various ways of the sheaths bonding are considered as well. Shock hazard and voltage stress of non-metallic outer sheath of cables are...
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Performance of data transmission in UMTS with turbo code about decreased number of states
PublicationIn the paper a structure of turbo encoder and decoder about decreased number of states has been described. The simulation results of transmission performance based on turbo coding without the reduction of the number of iterations for the uplink and downlink of WCDMA/FDD interface have been presented. The SOVA algorithm for turbo decoding has been used. The investigations have been carried out for Outdoor to Indoor & Pedestrian...
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Building Polish space sector – from small islands of excellence to a national innovation ecosystem
PublicationIn the paper a national potential of Poland to build its space industry after joining the European Space Agency (ESA) in 2012 is assessed, based on the series of survey reports published annually by POLSA since 2016. Their methodology was based on the ESA technology tree, classifying all the space-related technical knowhow and allowed identification of the most promising strengths to exploit and shortages to challenge by policymakers...
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Performance evaulation of video object tracking algorithm in autonomous surveillance system
PublicationResults of performance evaluation of a video object tracking algorithm are presented. The method of moving objects detection and tracking is based on background modelling with mixtures of Gaussians and Kalman filters. An emphasis is put on algorithm's efficiency with regards to its settings. Utilized methods of performance evaluation based on comparison of algorithm output to manually prepared reference data are introduced. The...
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Performance evaluation of video object tracking algorithm in autonomous surveillance system
PublicationResults of performance evaluation of a video object tracking algorithm are presented. The method of moving objects detection and tracking is based on background modelling with mixtures of Gaussians and Kalman filters. An emphasis is put on algorithm's efficiency with regards to its settings. Utilized methods of performance evaluation based on comparison of algorithm output to manually prepared reference data are introduced. The...
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Water uptake analysis of acceptor-doped lanthanum orthoniobates
PublicationIn this work, lanthanum orthoniobates doped with either antimony, calcium, or both have been synthesized and studied. The water uptake of the investigated materials has been analyzed by means of thermogravimetric studies. The results show the difference between the thermodynamics of hydration between the lanthanum orthoniobate system and other proton conducting ceramics. The relation between the water uptake and effective acceptor...
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Phase separation in poly(butylene terephthalate)-based materials prepared by solid-state modification
PublicationThe morphology of a series of poly(butylene terephthalate) (PBT)/fatty acid dimer diol (FADD)-based copolyesters prepared by solid-state modi fi cation (SSM) was studied. It was shown that in copolyesters containing less than 10 wt% FADD two different phases, i.e. a PBT crystalline phase and a PBT-rich amorphous phase, are present. The FADD residues were more or less homogeneously distributed throughout the interlamellar regions....
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Local Conformation and Cocrystallization Phenomena in Renewable Diaminoisoidide-Based Polyamides Studied by FT-IR, Solid State NMR, and WAXD
PublicationBiobased polyamides synthesized from diaminoisoidide (DAII), 1,4-diaminobutane, and sebacic acid are investigated by FT-IR, 13C{1H} magic-angle spinning/cross-polarization (CP/MAS) NMR spectroscopy, and WAXD. Their molecular conformation and mobility undergo distinct changes as a function of temperature and diaminoisoidide content in the compositions. The presence of randomly distributed diaminoisoidide (DAII) in the polyamides...
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Evolution of electrohydrodynamic flow of sduspended particles in a needle-to-plate negative DC corona discharge in air
PublicationCorona discharges are used for collecting dust in electrostatic precipitators (ESPs). The dust collection is mainlyrealized by the electric forces which move the ionized dust particles to the collecting electrodes. However, the presence of coronadischarge in the space between the charging and collecting electrodes in ESPs causes also the so-called ionic wind which set the gasmolecules and dust...
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Use of Modified Cuckoo Search algorithm in the design process of integrated power systems for modern and energy self-sufficient farms
PublicationIn the face of increasingly stringent pollutant emission regulations, designing an agricultural holding becomes a difficult challenge of connecting a large number of coefficients that describe an energy system of a farm in regard to its ecological and economic efficiency. One way to cope with this issue is to design an energy self-sufficient farm that integrates various technologies, including renewable energy. However, the selection...
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Low-Cost Method for Internal Surface Roughness Reduction of Additively Manufactured All-Metal Waveguide Components
PublicationIn this study, a novel low-cost polishing method for internal surface roughness reduction of additively manufactured components, developed for waveguide (WG) circuits operating in the millimeter frequency range is proposed. WG components fabricated using powder bed fusion (PBF) generally feature roughness of ten to fifty microns, which influences the increase of roughness-related conductor power losses having a major effect on...
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Enhancing electrical properties through in-situ controlled nanocrystallization of V2O5–TeO2 glass
PublicationV2O5–TeO2 glass–ceramics (VTGC) were prepared by controlled annealing of the V2O5–TeO2 glass (VTG), which illustrates a parent glass matrix with a single charge carrier. The annealing proceeded at six temperatures selected between the glass transition and the maximum of the frst crystallization process to obtain various nanocrystallite sizes. Heat treatment caused an increase in DC conductivity by 2.5–3.5 (250–285 °C) order of...
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Iron doped manganese cobaltite spinel coatings produced by electrophoretic co-deposition on interconnects for solid oxide cells: Microstructural and electrical characterization
PublicationWe report a systematic microstructural and electrical characterization of iron doped Mn–Co spinel coatings processed by electrophoretic co-deposition of Mn1.5Co1.5O4 and Fe2O3 powders on Crofer 22 APU and AISI 441 steel substrates. Iron addition to Mn–Co spinel coating leads to a reduction of the area specific resistance on both substrates, after 3200 h at 750 °C. The Fe doped Mn–Co coating both leads to a thinner oxide scale and...
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Hydration of Oxometallate Ions in Aqueous Solution
PublicationThe strength of hydrogen bonding to and structure of hydrated oxometallate ions in aqueous solution have been studied by double difference infrared (DDIR) spectroscopy and large-angle X-ray scattering (LAXS), respectively. Anions are hydrated by accepting hydrogen bonds from the hydrating water molecules. The oxygen atom of the permanganate and perrhenate ions form weaker and longer hydrogen bonds to water than the hydrogen bonds...
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Numerical Investigation on Dynamic Performance of a Multi-storey Steel Structure Model and Comparison with Experimental Results
PublicationShaking table testing is the most commonly adopted method to simulate earthquake forces. This approach allows us to analyze the dynamic performance and provides a valuable insight into the dynamics of building structures, which helps to improve their future safety and reliability. The present study aims to conduct a numerical evaluation of dynamic response of a multi-storey steel structure model, which was previously examined during...
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Numerical investigation on dynamic performance of a multi-storey steel structure model and comparison with experimental results
PublicationShaking table testing is the most commonly adopted method to simulate earthquake forces. This approach allows us to analyze the dynamic performance and provides a valuable insight into the dynamics of building structures, which helps to improve their future safety and reliability. The present study aims to conduct a numerical evaluation of dynamic response of a multi-storey steel structure model, which was previously examined during...
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Integracja bezprzewodowych heterogenicznych sieci IP dla poprawy efektywności transmisji danych na morzu
PublicationWraz ze wzrostem istotności środowiska morskiego w naszym codziennym życiu np. w postaci zwiększonego wolumenu transportu realizowanego drogą morską. czy zintensyfikowanych prac dotyczących obserwacji i monitoringu środowiska morskiego, wzrasta również potrzeba opracowania efektywnych systemów komunikacyjnych dedykowanych dla tego środowiska. Heterogeniczne systemy łączności bezprzewodowej integrowane na poziomie warstwy sieciowej...
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Innowacja urbanistyczna w kontekście kształtowania środowiska mieszkaniowego
Publication.
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A framework for detection of selfishness in multihop mobile ad hoc networks
PublicationThe paper discusses the need for a fully-distributed selfishness detection mechanism dedicated for multihop wireless ad hoc networks which nodes may exhibit selfish forwarding behaviour. The main contribution of this paper is an introduction to a novel approach for detecting and coping with the selfish nodes. Paper describes a new framework based on Dempster-Shafer Theory called Dempster-Shafer Theory-based Selfishness Detection...
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For Your Eyes Only – Biometric Protection of PDF Documents
PublicationThe paper introduces a concept of a digital document content encryption/decryption with facial biometric data coming from a legitimate user. Access to the document content is simple and straightforward, especially during collaborative work with mobile devices equipped with cameras. Various contexts of document exchange are presented with regard to the next generation pro-active digital documents proposed by authors. An important...
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THE IPV4 TO IPV6 MIGRATION OF APPLICATIONS AND SERVICE
PublicationThis article presents the problems related to IPv4 to IPv6 migration of applications supporting network services. It summarizes the needs of executing such migration. It shows the basic problems of automating the migration process, having defined the basic terms, i.e.: a network service, a network application. It shows a sample implementation of the automation of the migration process between IP technologies for selected network...
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Charakterystyka areodynamiczna membranowego przekrycia wiszącego.
PublicationArtykuł przedstawia charakterystykę aerodynamiczną membranowego przekrycia wiszącego. Prezentowane są dwie koncepcje przyjmowania wartości współczynnika aerodynamicznego. Pierwsza z koncepcji bazuje bezpośrednio na testach laboratoryjnych druga zaś wykorzystuje uproszczone podejście normowe.This paper presents the aerodynamic characteristics of membrane hanging roof. The two concepts of taking the value of the aerodynamic factor...
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Theoretical study of thermofrictional oscillations due to negative friction-temperature characteristic
PublicationAnalytical study on oscillations of a body on a moving counterbody has been done by assuming imperfect frictional thermal contact and friction that decreases with contact temperature. It has been shown that stick-slip oscillation occurs due to decrease of friction coefficient when the body moves in the opposite direction to the counterbody. Dynamical characteristics, such as conditions for stable sliding and limit cycles, have...
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Quality increase for single-welded joints of thin-walled structures by means of simulation modelling
PublicationThe Simulation calculation module and the SolidWorks software package have helped to define the optimal shape and dimensions of single-welded joints which may serve the basis for calculating the process parameters of welding. Having compared the models with different weld cross-sections the authors have defined that the weld height and width do not significantly affect the stress concentration, and the stress concentration and...
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NEW CONCEPT OF HYBRID PROPULSION WITH HYDROSTATIC GEAR FOR INLAND WATER TRANSPORT
PublicationThe article presents the development of author’s concept of a diesel/hydraulic propulsion system for inland watercraft. Due to specific nature of vessel navigation on rivers, classical propulsion systems with shaft lines can be effectively replaced by systems with hydraulic power transmission. A solution is also presented of a hybrid design with extra electric port having the form of a pumping system driven from a battery of accumulators....
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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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Aplikacja demonstrująca działanie kodów fontannowych
PublicationIstotną cechą kodów fontannowych jest możliwość odtwarzania nadawanych danych niezależnie od jakości kanału. Wynika to z tego, że kody te nie mają z góry założonej zawartości informacyjnej, a kolejne symbole nadmiarowe są generowane, dopóki jest taka potrzeba. Jest to szczególnie przydatne w transmisjach broadcastowych, bo każdy z odbiorców może zdekodować dane tak wcześnie, na ile pozwala jakość łącza. Aby przybliżyć funkcjonowanie...
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Effect of short time reduction on electrical properties of bismuth-silicate glasses
PublicationPodczas krótkiego wygrzewania szkieł bizmutowo-krzemianowych w wodorze (około 5 min w 375C) przewodnictwo powierzchniowe wzrasta o kilka rzędów wartości. Nośnikiem ładunku w tych próbkach jest hopping elektronowy między zlokalizowanymi stanami w badanej warstwie krzemu, zawierającej małe klastry Bi. Wpływ granul bizmutu na przewodnictwo jest widoczny w drugim stadium redukcji, które zachodzi po redukcji dłuższej niż 4h.
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Large Hydrodynamic Thrust Bearings and Their Application in Hydrogenerators
PublicationLarge hydrodynamic thrust bearings are the bearings which, due to hydrodynamic lubrication, allow large axial load to be transferred from a moving part (shaft) to the stationary part via a thin layer of the lubricant (usually oil), thus providing extremely low friction and practically no wear. Hydrogenerators with vertical shafts are the most important application of large thrust bearings. Main design and scientific problems of...
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Działanie na szkodę spółki zależnej - aspekty prawne
PublicationCelem artykułu jest prezentacja prawnych aspektów funkcjonowania grup kapitałowych w Polsce. Opracowanie dotyczy prawa grup spółek rozpatrywanego z punktu widzenia potrzeb działalności gospodarczej, z uwzględnieniem ochrony akcjonariuszy mniejszościowych, wierzycieli i menedżerów spółek tworzących holding, w szczególności spółek zależnych. Wykazano, że polski system prawa grup spółek nie spełnia zupełnie potrzeb współczesnego obrotu...
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Materials for Mediator-free Electron Transfer in the Enzymatic Electrodes of Biobatteries and Biofuel Cells
PublicationWe present functionalization of single-walled carbon nanotubes (SWCNTs) and their application in the enzymatic fuel cells construction. SWCNTs were covalently modified with different types of aromatic moieties. Free radical reaction was employed to create direct carbon-carbon bond between moiety and SWCNTs. In second approach functionalization takes place through amide bonding. Functionalized SWCNTs were characterized by spectroscopy...
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Co w architekturze piszczy? Dźwiękowy wymiar przestrzeni / What’s the buzz in architecture? – The sonic aspect of space
PublicationThe article presents a debate on the dividing line between architecture and the sound sciences. It sketches out the theoretical and practical aspects of space development in the context of its sonic reception. The analysis is based on examples of projects combining architecture and art in public space and their consequences for the reception of this space. The projects relate to the use of art in urban space with special emphasis...
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Contextualizing a Knowledge Base by Approximation – A Case Study
PublicationModular knowledge bases give their users opportunity to store and access knowledge at different levels of generality. In this paper we present how to organize a modular knowledge bases organized into contexts in which a user can express their knowledge in much simplified way, yet without losing its precision. The work is centered around the notion of approximation - i.e. reducing the arity of predicates used. The presentation is...
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Engineer's graphic workshop. Historical review.
PublicationThe paper introduces the history of development of graphic engineering workshop within European culture. The fundamentals of scientific approach to this subject are dated back to the XVIII century. Owning to Gaspard Monge's works descriptive geometry rose to the rank of branch of mathematics. As the time passes we observe the endeavors aiming at accelerating and automating the process of engineering drawing. Since the XX century...
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Load function walking pedestrian on the footbridge.
PublicationModern foot bridges are more and more sensitive to variable load created by moving pedestrians. These are several reasons for that. Quickly growing up road infrastructure forces us to build foot bridges just to reconnect one piece of land, separated now by the new road or railway. These bridges are lightweight because the only live load acting on them comes from pedestrians.The paper focuses on the definition of human induces dynamic...
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Learning and memory processes in autonomous agents using an intelligent system of decision-making
PublicationThis paper analyzes functions and structures of the memory that is an indispensable part of an Intelligent System of Decision-making (ISD), developed as a universal engine for autonomous robotics. A simplified way of processing and coding information in human cognitive processes is modelled and adopted for the use in autonomous systems. Based on such a knowledge structure, an artificial model of reality representation and a model...
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THE INFLUENCE OF MANUFACTURING OVERSIZING ON POSTWELDING DISTORTIONS OF THE FILLET WELDED JOINT
PublicationWelding proces is basic joining technique in shipbuilding. Such method generated welding distortions which cause a lot of problems during the manufacturing process. In the literature it is proposed wide spectrum of suggestions for a correct estimation of welding deformation in particular angular deformation in the fillet welded T joint. In the work influence of oversizing of weld on angular distortions of joint is presented basing...
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Development of beltless respiration and heartbeat sensor based on flexible piezoelectric film
PublicationThe main goal of this work is to report initial development on a respiration and heartbeat measurement sensor that can be used in continuous monitoring conditions at a minimal impact on the patient. General description of the sensor, consisting of a PVDF film and the bonding layer, is given. Open-circuit voltage generated by the sensor is estimated by analytical and numerical calculations. Analog and digital interface used to extract...