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Dynamics of fault arc traveling along busbars in high voltage switchboards = Dynamika łuku zwarciowego przemieszczającego się wzdłuż szyn rozdziel-nic wysokiego napięcia
PublicationThe paper presents the results of magnetic induction and electrodynamic force calculations acting on arc column during short-circuit in medium voltage air-insulated bus-bars. The gap between the bars was 120 mm and the prospective short-circuit currents ranged from 4 kA to 8 kA. The paper also shows the measurement results of average velocity fault arc depending on currents arc diameter and arc current was established and described....
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Smart experience engineering to support collaborative design problems based on constraints modelling
PublicationEngineering design is a knowledge intensive process. Experts' experiences from different product life-cycle stages play a key role in problem solving during design decision making by linking up knowledge to find better solutions for a specific design problem. Different approaches have been used to support Collaborative and Concurrent Product Design, such as Constraint Satisfaction Problem (CSP) modelling. Additionally, due to the...
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Relacje między przeszłością a teraźniejszością we współczesnych muzeach na przykładach New Acropolis Museum w Atenach i Neues Museum w Berlinie = Relations between past and present in contemporary museums illustrated by the New Acropolis Museum in Athens and the Neues Museum in Berlin
PublicationStreszczenie: Opracowanie dotyczy relacji pomiędzy dziedzictwem historycznym a nowoczesnością we współczesnych muzeach. Przytoczone przykłady to obiekty nowe, które powstały w unikalnym historycznym otoczeniu oraz odrestaurowane, o ważnym znaczeniu kulturowym. Współczesne możliwości techniczne, szczególnie nowoczesne technologie szkła oraz wykorzystanie technik cyfrowych w projektowaniu, pozwalają łączyć elementy i rozwiązania...
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Analysis of unsteady flow forces on the thermowell of steam temperature sensor
PublicationIn this paper, 3D numerical analysis of unsteady flow forces acting on the measuring sheath of steam temperature is presented. According to that purpose, the CFD (Computation Fluid Dynamic [1]) approach has been used. The nonstationary of fluid acting on the measuring sheath such as: Strouhal frequency, amplitude of pressure, structure of vortex, peak of pressure, field of pressure, field of velocity etc. are studied analytically...
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Generative Process Planning with Reasoning based on Geometrical Product Specification
PublicationThe focus of this paper is on computer aided process planning for parts manufacture in systems of definite process capabilities, involving the use of multi-axis machining centers for parts shaping and grinding machines for finishing. It presents in particular a decision making scheme for setup determination as a part of generative process planning. The planning procedurę consists of two stages. The first stage is associated with...
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Big Data Analytics for ICT Monitoring and Development
PublicationThe expanded growth of information and communication technology has opened new era of digitization which is proving to be a great challenge for researchers and scientists around the globe. The utmost paradigm is to handle and process the explosion of data with minimal cost and discover relevant hidden information in the least amount of time. The buzz word “BIG DATA” is a widely anticipated term with the potential to handle heterogeneous,...
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Assessment and design of greener deep eutectic solvents – A multicriteria decision analysis
PublicationDeep eutectic solvents (DES) are often considered as green solvents because of their properties, such as negligible vapor pressure, biodegradability, low toxicity or natural origin of their components. Due to the fact that DES are cheaper than ionic liquids, they have gained many applications in a short period of time. However, claims about their greenness sometimes seem to be exaggerated. Especially, bearing in mind lots of data...
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The effect of macro polymer fibres length and content on the fibre reinforced concrete
PublicationThe paper presents studies of a ready-mix concrete containing polymer fibres of three different lengths: 24, 38 and 54 mm. The performed tests allowed to determine the effect of fibre volume fraction and length on the concrete strength. The basic parameters of concrete mixture (consistency, air content and bulk density) were identified. Fibre reinforced concrete belongs to a group of composite materials. The polymer fibres are...
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Finite-element analysis of a base-isolated multi-storey steel building under seismic motions
PublicationNumerical simulation of the seismic behaviour of a multi-storey steel building, both fixed-base and base-isolated, under the 1940 El Centro earthquake was performed in this paper. The analyzed 4-storey building was decoupled from the shaking ground with the Polymeric Bearings, which can be considered a proposal of a new seismic isolation system. It consists of rectangular-shaped blocks made of a specially prepared flexible polymeric...
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Towards More Realistic Probabilistic Models for Data Structures: The External Path Length in Tries under the Markov Model
PublicationTries are among the most versatile and widely used data structures on words. They are pertinent to the (internal) structure of (stored) words and several splitting procedures used in diverse contexts ranging from document taxonomy to IP addresses lookup, from data compression (i.e., Lempel- Ziv'77 scheme) to dynamic hashing, from partial-match queries to speech recognition, from leader election algorithms to distributed hashing...
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Road texture influence on tire rolling resistance
PublicationTire rolling resistance is one of the most important resistive forces acting on road vehicles. It depends on tire and surface characteristics as well as vehicle operating parameters. This paper deals with the influence of road surface texture on rolling resistance of passenger car tires. Results of road measurements performed on variety of road surfaces are presented.
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THE POSSIBILITY OF USE OF LASER-MODIFIED Ti6Al4V ALLOY IN FRICTION PAIRS IN ENDOPROSTHESES
PublicationThe purpose of this paper is to show results of laser treatment at cryogenic conditions of the Ti6Al4V alloy used for orthopedic applications. That modification process ought to bring beneficial changes of microstructure and residual stresses in the surface layer. The paper presents the abrasive wear of the base and laser remelted material in association with ceramics Al2O3. Despite the surface cracking after laser treatment the...
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Self-tuning adaptive frequency tracker
PublicationAn automatic gain tuning algorithm is proposed for a recently introduced adaptive notch filter. Theoretical analysis and simulations show that, under Gaussian random-walk type assumptions, the proposed extension is capable of adjusting adaptation gains of the filter so as to minimize the mean-squared frequency tracking error without prior knowledge of the true frequency trajectory. A simplified one degree of freedom version of...
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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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Accelerometer-based Human Activity Recognition and the Impact of the Sample Size
PublicationThe presented study focused on the recognition of eight user activities (e.g. walking, lying, climbing stairs) basing on the measurements from an accelerometer embedded in a mobile device. It is assumed that the device is carried in a specific location of the user’s clothing. Three types of classifiers were tested on different sizes of the samples. The influence of the time window (the duration of a single trial) on selected activities...
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Zastosowanie obserwatora ATO do filtracji wyników estymacji położenia w napędzie z silnikiem PMSM
PublicationW referacie zaproponowano zastosowanie obserwatora ATO (ang. Angle Tracking Observer) do poprawy dokładności odtwarzania położenia kątowego wirnika silnika PMSM (ang. Permanent Magnet Synchronous Motor) za pomocą estymatora fizykalnego. Opracowano dedykowaną, uproszczoną strukturę ATO. Zaproponowano procedurę doboru nastaw wzmocnień obserwatora w oparciu o model symulacyjny. Skuteczność działania ATO potwierdzono badaniami eksperymentalnymi.
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Historical crane on the redesigned original trestle bridge as a memorial of Gdansk Shipyard
PublicationThe paper includes selected aspects of the study, whose goal is to hold the historical crane 642-24 in its current location after the modification of trestle bridge static scheme. The scope of the paper includes the assessment of current technical condition of the object, a presentation of FEM analyses, a description of the assumed load cases, results of the static calculations, checking the effort of construction elements, global...
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Studying the Behaviour of Pedestrians and Drivers Within Pedestrian Crossings
PublicationEvery third road accident in Poland involves a pedestrian as a participant or, most of the time, a casualty. Pedestrian accidents are usually the result of complex situations and the outcome of a number of factors related to driver and pedestrian behaviour and road infrastructure. Safety depends largely on how well the traffic condition is perceived and on visibility in traffic. The re-lations between pedestrians and motorists...
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Functional properties of edible films for food applications - a review
PublicationApplication of natural polymers to forming edible films for food applications has been reviewed. Due to the hydrophilic nature of proteins and polysaccharides, films prepared from these polymers are too susceptible to moisture. Modification of them with critically selected a suitable compounds can result in their improved functional properties and making them useful for food packaging.
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TEORIA DECYZYJNYCH PROCESÓW SEMI-MARKOWA I JEJ ZASTOSOWANIE W PROJEKTOWANIU I EKSPLOATACJI OKRĘTOWYCH SILNIKÓW GŁÓWNYCH I INNYCH URZĄDZEŃ SIŁOWNI OKRĘTOWYCH
PublicationW referacie zaprezentowano znaczenie teorii procesów semi-Markowa w naukach technicznych, zwłaszcza w teorii niezawodności urządzeń technicznych, teorii bezpieczeństwa ich działania oraz statystycznej teorii podejmowania decyzji eksploatacyjnych. W referacie wyeksponowano także przydatność teorii procesów semi-Markowa w teorii i praktyce eksploatacji wspomnianych urządzeń technicznych na przykładzie tak istotnych urządzeń w transporcie...
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Suitability study of hybrid model of electrodynamic actuator
PublicationThis paper presents the proposal of the hybrid circuit-field model of an electrodynamic actuator. The field model uses the inductor current as the input data which is obtained from the circuit model or experimentally. The field model implemented using the FLUX program makes it possible to easily determine the pressure distribution acting on the disc. The results have been verified experimentally.
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Weldability of high strength steel in underwater environment
PublicationThe article describes the problems with weldability of high-strength steels in the aquatic environment. The tendency of steel S355J2G3 and S500M to form cold cracks when welded in wet welding conditions has been experimentally evaluated. It was found that the tested steels have a high propensity to cracking. An experiment has been proposed and tested to evaluate the usefulness of the tempering bead technique as a method of improving...
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Annotating Words Using WordNet Semantic Glosses
PublicationAn approach to the word sense disambiguation (WSD) relaying onthe WordNet synsets is proposed. The method uses semantically tagged glosses to perform a process similar to the spreading activation in semantic network, creating ranking of the most probable meanings for word annotation. Preliminary evaluation shows quite promising results. Comparison with the state-of-theart WSD methods indicates that the use of WordNet relations...
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Integration and Visualization of the Results of Hydrodynamic Models in the Maritime Network-Centric GIS of Gulf of Gdansk
PublicationEnsuring of security in the coastal area makes on a seaside countries research in the field of infrastructure spatial information of environmental data. The paper presents the results of work on the construction of this infrastructure by integrating electronic navigational chart with ortophotomaps of coastal areas as well as numerical data from weather and hydrodynamic models. Paper focuses on a problems associated with creating...
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Integrating Experience-Based Knowledge Representation and Machine Learning for Efficient Virtual Engineering Object Performance
PublicationMachine learning and Artificial Intelligence have grown significant attention from industry and academia during the past decade. The key reason behind interest is such technologies capabilities to revolutionize human life since they seamlessly integrate classical networks, networked objects and people to create more efficient environments. In this paper, the Knowledge Representation technique of Set of Experience...
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Novel stationary phases based on asphaltenes for gas chromatography
PublicationWe present the results of investigations on the possibility of the application of the asphaltene fraction isolated from the oxidized residue from vacuum distillation of crude oil as a stationary phase for gas chromatography. The results of the investigation revealed that the asphaltene stationary phases can find use for the separation of a wide range of volatile organic compounds. The experimental values of Rohrschneider/McReynolds...
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Effects of CO2 and Nd:YAG Laser Remelting of the Ti6Al4V Alloy on the Surface Quality and Residual Stresses
PublicationThe titanium alloys are materials susceptible to tribological wear and the laser treatment can be applied in surface treatment processes to obtain for example higher hardness level. From the other side, it is important to take into consideration, that hardness increase that can be connected with cracks . The aim of this research was to investigate the effects of different lasers and the process parameters on the form and level...
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Comparison of AHP and Numerical Taxonomy Methods Based on Biogas Plant Location Analysis
PublicationThe paper presents a comparison of the multi-criteria Analytic Hierarchy Process (AHP) method and numerical taxonomy in biogas plant location selection. Biogas plants are sources that will significantly contribute to the implementation of the provisions of the energy and climate package for Poland by 2030. Increasing the share of energy produced from renewable sources, e.g. biogas plants, will increase the country’s energy security....
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Damage of a post-tensioned concrete bridge – Unwanted cracks of the girders
PublicationThe cracking of a post-tensioned T-beam superstructure, which was built using the incremental launching method, is analyzed in the paper. The problem is studied in detail, as specific damage was observed in the form of longitudinal cracks, especially in the mid-height zone of the girder at the interface of two assembly sections. The paper is a case study. A detailed inspection is done and non-destructive testing results of the...
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Representativity of ISO test track surface based on controlled pass-by measurements
PublicationWithin the Polish-Norwegian research project ELANORE, a limited Round Robin Test has been performed on four ISO tracks in Northern Europe. The basic objective of the project is to improve the EU directive on labelling of tyres for noise and rolling resistance. This directive is based on the measurement procedures proscribed in the UNECE Reg.117. Measurements on 3 ISO tracks were performed in 2021 and presented at InterNoise 2022....
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Comparison of pavement noise properties on selected road sections using different CPX measuring systems: self-powered vehicle and special test trailer
PublicationThe recently published ISO standard intended to measure the noise properties of road surfaces in a standardized method (ISO 11819-2:2017) precisely defines measurement procedure of the influence of road surface on traffic noise. According to it, two types of test vehicles may be utilized: a self-powered vehicle fitted with one or more test tyres and a trailer towed by a separate vehicle with one or more test tyres mounted on the...
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Oxidation and hydrogen behavior in Zr-2Mn alloy
PublicationThe purpose of the present research was to determine the oxidation and hydrogenation behavior in the new Zr-2Mn alloy. The oxidation of alloy was performed at temperatures between 350°C and 900°C for 30 minutes. The hydrogen charging was made for 72 h at a current density 80 mA/cm2. The charged samples were heat treated at 400°C for 4 h to obtain a uniform hydrogen profile content across the sample. The oxidation resulted in an...
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Damage Detection Strategies in Structural Health Monitoring of Overhead Power Transmission System
PublicationOverhead power transmission lines, their supporting towers, insulators and other elements create a highly distributed system that is vulnerable to damage. Typical damage scenarios cover cracking of foundation, breakage of insulators, loosening of rivets, as well as cracking and breakage of lines. Such scenarios may result from various factors: groundings, lightning strikes, floods, earthquakes, aeolian vibrations, conductors galloping,...
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The Most Valuable Global Brands and Condition of Economies: a Spatial Approach
PublicationResearch background: Brands are considered to be the most valuable asset of a company. Some of them achieve spectacular global results. The significance of global brands is proved by the fact that their value is often greater than the sum of all company’s net assets. Purpose of the article: The aim of this article is to highlight that brand value does not only create company’s value but also leverages economies. We claim that even though...
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Stability of roof trusses stiffened by corrugated sheets
PublicationThe present parametric study is devoted to the stability analysis of a set of trusses stiffened by decking of corrugated steel sheets. For different parameters of corrugated sheets the critical loading of the roof is calculated. In the parametrical analysis the threshold bracing condition of the roof is obtained. Then the geometrically non-linear analysis of trusses braced by corrugated sheets was conducted. As a results of non-linear...
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A simple way of increasing estimation accuracy of generalized adaptive notch filters
PublicationGeneralized adaptive notch filters are used for identification/tracking of quasi-periodically varying dynamic systems and can be considered an extension, to the system case, of classical adaptive notch filters. It is shown that frequency biases, which arisein generalized adaptive notch filtering algorithms, can be significantly reduced by incorporating in the adaptive loop an appropriately chosen decision delay. The resulting performance...
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Symulacja hałasu pojazdów w trakcie manewrowania z małymi prędkościami - model CP2009
PublicationOgraniczenie halasu związanego z ruchem drogowym możliwe jest jedynie poprzez skoordynowane dzialanie w zakresie doskonalenia pojazdów, opon nawierzchni drogowych i organizacji ruchu drogowego. Praca porusza zagadnienia związane z manewrowaniem pojazdów na parkingach, stacjach paliw, terminalach promowych itp. Omówiono metodę prognozowania poziomu mocy akustycznej emitowanej z obiektu typu parking z uwzględnieniem charakterystyk...
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MEASUREMENT O F HEALTHCARE SYSTEM EFFICIENCY IN OECD COUNTRIES
PublicationIncreased spending on healthcare systems in many countries tends to attract attention to their efficiency. The aim of this paper is to evaluate the efficiency of healthcare systems in the OECD countries and indicate causes of inefficiency by applying Data Envelopment Analysis (DEA) and using additive and super-efficiency models. The homogeneity of the sample is assessed and outliers are excluded. A ranking is established on the...
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DYNAMIC ANALYSIS OF THE IMPACT OF VIBRATION ON HISTORICAL BUILDINGS - AN OWN PROJECT OF EXTERNAL STAIRCASE
PublicationThis article presents numerical simulations that concern modeling of interaction of the external staircase’s construction with the observation deck on historic water tower located at Gdansk University of Technology. The interaction occurring according to various methods of the staircase's construction support on the wall of the historic tower was compared. The external staircase that allows for entering onto the monument was subjected...
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Information Logistics as a Paradigm
PublicationThis paper presents a paradigm-based approach to information logistics. The approach deals with extracting concepts specific to information logistics in categories typical to paradigms. The resulting description should be easily connected to complementary components which are based on other paradigms, e.g. business process management and information systems development. Empirical part aims at checking and enhancing features typical...
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On bidirectional preestimates and their application to identification of fast time-varying systems
PublicationWhen applied to the identification of time-varying systems, such as rapidly fading telecommunication channels, adaptive estimation algorithms built on the local basis function (LBF) principle yield excellent tracking performance but are computationally demanding. The subsequently proposed fast LBF (fLBF) algorithms, based on the preestimation principle, allow a substantial reduction in complexity without significant performance...
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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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The concept of capillary forces supported evaporator for application to domestic ORC unit
PublicationIn the paper presented are studies on the investigation of the capillary forces effect inducted in the porous structure of a loop heat pipe. The potential application of such heat exchanger is for example an evaporator of the domestic micro CHP unit. Preliminary analysis of the results indicates water as having the best potential, however taking into account all issues it can be said that the best effect is obtained using ethanol.
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Multiple-channel frequency-adaptive active vibration control using SONIC
PublicationSONIC (self-optimizing narrowband interference canceller) is an acronym of a new approach to rejection of sinusoidal disturbances acting at the output of a discretetime stable linear plant with unknown and possibly timevarying dynamics. The paper presents two frequency-adaptive extensions of the multivariate SONIC algorithm. The efficacy of the proposed solutions is tested using our laboratory-scale active vibration control plant.
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Balance recognition on the basis of EEG measurement.
PublicationAlthough electroencephalography (EEG) is not typically used for verifying the sense of balance, it can be used for analysing cortical signals responsible for this phenomenon. Simple balance tasks can be proposed as a good indicator of whether the sense of balance is acting more or less actively. This article presents preliminary results for the potential of using EEG to balance sensing....
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Wyniki badań parkingowych w obszarze Śródmieścia Gdyni.
PublicationW referacie przedstawiono metodykę i wyniki badań parkingowych, które przeprowadzono w obszarze Strefy Płatnego Parkowania w Gdyni w ramach projektu CIVITAS DYN@MO. Badania prowadzone były w celu możliwości określenia wpływu graniczenia/zamknięcia ruchu na wybranych ciągach ulic.
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Research of the changeability of the vessels traffic intensity of inland waterways – case study for Lower Vistula
PublicationThe article presents an analysis of the changeability of traffic intensity of inland waterway vessels in the Vistula Delta. The concept of traffic intensity was defined, traffic flows and disturbances were identified in the studied area. The characteristics of the inland waterway traffic model are presented. The results of the analysis indicate the need to carry out modernization of inland waterways for the needs of inland waterway...
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A Multi Rig Screening Test for Thin Ceramic Coatings in Bio-Tribological Applications
PublicationZaprezentowano metodę badań ogólnej charakterystyki tribologicznej cienkich powłok ceramicznych z wykorzystaniem równoległych testów na wielu stanowiskach o różnej konfiguracji styku powierzchni trących i przy ruchu o różnym charakterze (jednokierunkowym i posuwisto zwrotnym). Przedstawiono wyniki porównania przy pomocy jednoczesnej analizy wyników testów z różnych stanowisk; w wyniku testów uzyskano ranking powłok ze wskazaniem...
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Effect of Soft Handover on the Capacity of WCMDA/FDD Interfece Using MRC RAKE Receiver in Uplink
PublicationIn the paper the mechanism of soft and hard hanover in UMTS is presented. Simulation tests for different services having various performance requirements and transmission rates have beeen made. Simulation results showing effect of soft handover in comparison with hard handover on the capacity of WCMDA/FDD radio interfaceare described, when the RAKE receiver with Maximal Ratio Combining has been implemented in RNC.
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Intranet and internal communication in an organization
PublicationOne of the conditions of an organizational effectiveness is acommunication. However, communication meets some obstacles. Newtechnological opportunities, such as Intranet support enterprise communication process and bring some benefits. This paper includes: the description of communication process and its barriers, the analyze of relationships between communication and an organizational effectiveness, advantages from implementing...