Filters
total: 1794
filtered: 1547
-
Catalog
- Publications 1547 available results
- Journals 10 available results
- Conferences 3 available results
- Publishing Houses 1 available results
- People 24 available results
- Inventions 1 available results
- Projects 4 available results
- Research Equipment 1 available results
- e-Learning Courses 32 available results
- Events 3 available results
- Open Research Data 168 available results
Chosen catalog filters
displaying 1000 best results Help
Search results for: FDM SCHEMES
-
THEORETICAL AND EXPERIMENTAL INVESTIGATION OF THIN-WALLED BEARING SHELL’S DESIGN PARAMETERS AND ASSEMBLY CONDITIONS ON THE HOLDING TORQUE INSIDE A HOUSING BORE OF A CONNECTING ROD
PublicationThe aim of the work was the experimental and theoretical evaluation of the influence of the most important parameters determining the holding torque of a thin-walled bearing shell inside a housing bore of a connecting rod. The main investigated parameters were defned by authors experience in this feld. In the frst stage of research, a special test stand was designed in order to allow measuring the real values of the friction torque...
-
DYNAMIC RESPONSE OF FORUM GDANSK STRUCTURE DUE TO RAIL TRAFFIC
PublicationThe paper presents the study of the impact of vibration induced by the movement of the railway rolling stock on the Forum Gdańsk structure. This object is currently under construction and is located over the railway tracks in the vicinity of the Gdańsk Główny and Gdańsk Śródmieście railway stations. The analysis covers the influence of vibrations on the structure itself and on the people within. The in situ measurements on existing...
-
Special Issue "Applications of Finite Element Modeling for Mechanical and Mechatronic Systems"
PublicationNumerical modeling is very important in today's engineering because, among other things, it reduces the costs associated with prototyping or predicting the occurrence of potentially dangerous situations during operation in certain defined conditions. Different methods have so far been used to implement the real structure into the numerical version. The most popular have been variations of the finite element method (FEM). The aim...
-
Silent Sonar with matched filtration
PublicationRadars with continuous wave frequency (CW FM sonars) are used in radiolocation as 'silent sonars'. They determine the distance to target by measuring the difference between the frequency of the sounding signal and echo signal. The article presents the principle of operation and parameters of silent CW FM sonars. Target distance determined by these sonars is based on the signal at the output of the matched filter. The Doppler effect...
-
Evaluation of the content of inorganic anions in tree saps
PublicationTree saps were once commonly used in the countries of Northern, Central and Eastern Europe. Although once almost forgotten, their popularity has been growing recently as part of an interest in organic food and traditional medicine. Tree saps, tapped mainly from birch and maple trees, are drunk both fresh and fermented or are used as raw material for the production of food products, e.g. syrups. The aim of this study was to determine...
-
Dissociative electron attachment of furan, tetrahydrofuran, and fructose
PublicationPrzeprowadzono badania wychwytu dysocjacyjnego elektronów w cząsteczkach furanu, tetrahydrofuranu i fruktozy w przedziale energii 0-14eV. Stwierdzono, że w przypadku wychwytu elektronów o energiach poniżej progu wzbudzenia (< 3eV), jedynie fruktoza jest podatna na rozerwanie pierścienia cukrowego. W cząsteczkach furanu i tetrahydrofuranu struktury rezonansowe odpowiadające fragmentom pierścienia pojawiają się dla energii elektronów...
-
Ocena pracy dźwigara zadaszenia Hali Blanika w Gdańsku
PublicationWartykule przedstawiono kompleksowe sprawdzenie nośności stalowej konstrukcji zadaszenia Hali Leszka Blanika w Gdańsku. Dokonano oceny wpływu otworów dużej średnicy w środnikach dźwigara na jego nośność. Oszacowano nośność nietypowego, zginanego styku doczołowego łączącego elementy dwuteowe klasy 4. Obliczenia wykonano na podstawie norm i analiz modeli MES.
-
PLANNING FOR THE NORTH-EUROPEAN WATERFRONT CITIES
PublicationRedevelopment of urban waterfronts is one of the leading themes in contemporary planning practice. This issue is a subject of interest to many scholars and practitioners, associated with development of waterfront cities. In literature on this topic one can find a lot of information regarding leading examples of this process, discussion of issues and problems associated with this phenomenon as well as analysis of the results achieved....
-
Tuning the ferromagnetic phase in the CDW compound SmNiC2 via chemical alloying
PublicationWe report a study on tuning the charge density wave (CDW) ferromagnet SmNiC2 to a weakly coupled superconductor by substituting La for Sm. X-ray diffraction measurements show that the doped compounds obey Vegard’s law, where La (Lu) alloying expands (shrinks) the lattice due to its larger (smaller) atomic size than Sm. In the series Sm1−xLaxNiC2, CDW transition (TCDW =148K) for SmNiC2 is gradually suppressed, while the ferromagnetic...
-
The effect of shear deformations' rotary inertia on the vibrating response of multi-physic composite beam-like actuators
PublicationIn consecutive studies on flexomagneticity (FM), this work investigates the flexomagnetic reaction of a vibrating squared multi-physic beam in finite dimensions. It is assumed that the bending and shear deformations cause rotary inertia. In the standard type of the Timoshenko beam the rotary inertia originated from shear deformations has been typically omitted. It means the rotary inertia resulting from shear deformation is a new...
-
Deformation Analysis of a Composite Bridge during Proof Loading Using Point Cloud Processing
PublicationRemote sensing in structural diagnostics has recently been gaining attention. These techniques allow the creation of three-dimensional projections of the measured objects, and are relatively easy to use. One of the most popular branches of remote sensing is terrestrial laser scanning. Laser scanners are fast and efficient, gathering up to one million points per second. However, the weakness of terrestrial laser scanning is the...
-
Effect of the ex situ physical and in situ chemical modification of bacterial nanocellulose on mechanical properties in the context of its potential applications in heart valve design
PublicationBacterial nanocellulose (BNC) is a promising material for heart valve prostheses. However, its low strength properties limit its applicability in cardiovascular surgery. To overcome these limitations, the mechanical properties of BNC can be improved through modifications. The aim of the research was to investigate the extent to which the mechanical properties of BNC can be altered by modifying its structure during its production...
-
Reinforced concrete thin wall dome after eighty years of operation in maritime climate environment
PublicationThe paper presents a description of the construction elements of the Gdynia Seaport main hall dome. Firstly, it provides information about the technical condition of the dome’s structure. Secondly, it examines the strength analysis of the thin-walled reinforced concrete dome covering. Throughout the last 80 years the building has been exposed to an unfavourable marine climate. The analysis of the state of stress and deformations...
-
Novel analysis methods of dynamic properties for vehicle pantographs
PublicationTransmission of electrical energy from a catenary system to traction units must be safe and reliable especially for high speed trains. Modern pantographs have to meet these requirements. Pantographs are subjected to several forces acting on their structural elements. These forces come from pantograph drive, inertia forces, aerodynamic effects, vibration of traction units etc. Modern approach to static and dynamic analysis should...
-
Assessment of the Bulgarian Wastewater Treatment Plants’ Impact on the Receiving Water Bodies
PublicationDeterioration of water quality is a major problem world widely according to many international non-governmental organizations (NGO). As one of the European Union (EU) countries, Bulgaria is also obliged by EU legislation to maintain best practices in assessing surface water quality and the efficiency of wastewater treatment processes. For these reasons studies were undertaken to utilize ecotoxicological (Microtox®, Phytotoxkit...
-
Experimental and Numerical Investigation of Tensile and Flexural Behavior of Nanoclay Wood-Plastic Composite
PublicationIn this study, the effect of wood powder and nanoclay particle content on composites’ mechanical behavior made with polyethylene matrix has been investigated. The wood flour as a reinforcer made of wood powder was at levels of 30, 40, and 50 wt.%, and additional reinforcement with nanoclay at 0, 1, 3, and 5 wt.%. Furthermore, to make a composite matrix, high-density polyethylene was used at levels of 70, 60, and 50% by weight....
-
Merging extremum seeking and self-optimizing narrowband interference canceller - overdetermined case
PublicationActive cancellation systems rely on destructive interference to achieve rejection of unwanted disturbances entering the system of interest. Typical practical applications of this method employ a simple single input, single output arrangement. However, when a spatial wavefield (e.g. acoustic noise or vibration) needs to be controlled, multichannel active cancellation systems arise naturally. Among these, the so-called overdetermined...
-
On Symmetry of Uniform and Preferential Attachment Graphs
PublicationMotivated by the problem of graph structure compression under realistic source models, we study the symmetry behavior of preferential and uniform attachment graphs. These are two dynamic models of network growth in which new nodes attach to a constant number m of existing ones according to some attachment scheme. We prove symmetry results for m=1 and 2 , and we conjecture that for m≥3 , both models yield asymmetry with high...
-
Analysis of an Attenuator Artifact in an Experimental Attack by Gunn–Allison–Abbott Against the Kirchhoff-Law–Johnson-Noise (KLJN) Secure Key Exchange System
PublicationA recent paper by Gunn–Allison–Abbott (GAA) [L. J. Gunn et al., Scientific Reports 4 (2014) 6461] argued that the Kirchhoff-law–Johnson-noise (KLJN) secure key exchange system could experience a severe information leak. Here we refute their results and demonstrate that GAA’s arguments ensue from a serious design flaw in their system. Specifically, an attenuator broke the single Kirchhoff-loop into two coupled loops, which is an...
-
Recommendations for Urban Freight Policy Development in Gdynia
PublicationThe purpose of this paper was to provide practical recommendations on how to develop Gdynia’s urban freight policy based on actual planning experience and characteristics of potential measures. Freight policy scheme was developed as a result of three interrelated factors: a) the general procedure of the urban freight planning, b) the city's current planning stage analysis and, c) characteristics of urban freight objectives and...
-
Pulse-Width Modulation Template for Five-Level Switch-Clamped H-Bridge-Based Cascaded Multilevel Inverter
PublicationThis article presents a carrier-based pulse-width modulation (PWM) template for a 5-level, H bridge-based cascaded multilevel inverter (MLI). The developed control concept generates adequate modulation template for this inverter topology wherein a sinusoidal modulating waveform is modified to fit in a single triangular carrier signal range. With this modulation approach, classical multiplicity and synchronization of the triangular...
-
A Comprehensive Investigation of Knowledge Management Publications
PublicationRecent trends in knowledge management (KM) have increasingly indicated a lack of agreement, integration and classification between different KM domains. As such, experts are inadequately equipped when attempting to classify KM into their specific areas that could effectively contribute to a technocratic approach behind the organizational strategy. This paper illustrates a method of classifying KM publications by using a scheme...
-
Where Did Knowledge Management Go?: A Comprehensive Survey
PublicationKnowledge Management (KM) research outputs have been expanding exponentially in the past years, generating diversified topics, which lack integration and classification. It has been challenging for experts to classify KM because of its versatile open fields, and in our view, it contributes to the technocratic approach remaining behind the organizational approach. This paper highlights a way to classify KM publications through a...
-
Robust-adaptive dynamic programming-based time-delay control of autonomous ships under stochastic disturbances using an actor-critic learning algorithm
PublicationThis paper proposes a hybrid robust-adaptive learning-based control scheme based on Approximate Dynamic Programming (ADP) for the tracking control of autonomous ship maneuvering. We adopt a Time-Delay Control (TDC) approach, which is known as a simple, practical, model free and roughly robust strategy, combined with an Actor-Critic Approximate Dynamic Programming (ACADP) algorithm as an adaptive part in the proposed hybrid control...
-
MULTI-CRITERIA MODEL IN MULTIFUNCTIONAL BUILDING SYSTEM DESIGN PROCESS
PublicationThe paper presents a multi-criteria approach in multifunctional building system design process. The aim is to develop a theory relative to the engineering system of multifunctional with a mathematical representation defined by a holistic network for the lifecycle of the designed object. The idea of work was to define the structure of a complex system. Background for the presented field is to develop a design strategy for multifunctional...
-
Two-dimensional vertical Reynolds-averaged naviers-stokes equations versus one-dimensional Saint-Venant model for rapidly varied open channel water flow modelling
PublicationPrzedstawiono dwa modele przepływu wody ze swobodną powierzchnią -płaski pionowy model Reynoldsa i model de Saint-Venanta.Do rozwiązania równań pierwszego modelu zastosowano schemat SIMPLE oraz wykorzystano metodę cząstek znaczonych MAC do wyznaczania swobodnej powierzchni wody. Równania Saint-Venanta rozwiązano metodą objętości skończonych. Obydwa modele zastosowano do symulacj zjawiska typu katastrofa zapory. Porównano wyniki...
-
Technologie przewozu i przeładunku w transporcie morskim
PublicationPorty morskie są skomplikowanymi węzłami infrastruktury transportowo-logistycznej o szerokim spektrum funkcjonalności . Rdzeniem funkcjonalnym portów jest zwykle kilka lub kilkanaście terminali przeładunkowo-składowych, wyspecjalizowanych w obsłudze określonych grup ładunków drobnicowych, masowych suchych i masowych płynnych (patrz schemat 1). Ze względu na różnice we właściwościach ładunków, i wynikających z tego faktu zróżnicowanych...
-
Globalny system monitoringu transportu kontenerowego
PublicationOpisano globalny bezprzewodowy system monitoringu ładunków kontenerowych, jako rozwiązanie podnoszące bezpieczeństwo i efektywność takiego transportu. W sposób ogólny opisano schemat funkcjonalny systemu oraz tzw. inteligentny moduł kontenerowy (IMK), stanowiący wyposażenie każdego kontenera, na którym to module opiera się budowa i działanie tego systemu. Następnie opisano działanie samoorganizującej się sieci takich modułów, co...
-
Old Problems - New Solutions: Conversion of Capitals as a Tool for Shaping the Competitive Position in the Economic Field
PublicationThe acts and operations any social actor effectuates in each of the logically distinguished spheres of reality are conditioned by many factors, among which a reliable analysis of the strengths and weaknesses of an agent should be considered of utmost importance. The concept of capitals presented in this article divides the quantity of resources available to all acting agents into four main categories (which allows for determining...
-
Wykorzystanie potencjału transportowego Dolnej Wisły
PublicationW pracy zawarto koncepcję rozwoju drogi wodnej Wisły na odcinku Bydgoszcz - Gdańsk. Przedstawione są bariery utrudniające rozwój transportu wodnego i przesłanki przemawiające za aktywizacją dróg wodnych w Polsce. Zaproponowano drogę wodną Wisły jako łańcuch w ogólnopolskiej sieci transportowej, z terminalami kontenerowymi na istniejących nabrzeżach w Porcie Gdańsk i nowym terminalem w Bydgoszczy, a także połączono ją z ogólnopolską...
-
Old Problems - New Solutions: Conversion of Capitals as a Tool for Shaping the Competitive Position in the Economic Field
PublicationThe acts and operations any social actor effectuates in each of the logically distinguished spheres of reality are conditioned by many factors, among which a reliable analysis of the strengths and weaknesses of an agent should be considered of utmost importance. The concept of capitals presented in this article divides the quantity of resources available to all acting agents into four main categories (which allows for determining...
-
Nowy mechanizm dynamicznego sterowania mocą w systemie UMTS.
PublicationW referacie zaprezentowano nowy mechanizm dynamicznego sterowania mocą, pracujący z częstotliwością 3000 rozk/sek, możliwy do zastosowania w interfejsie radiowym WCDMA/FDD systemu UMTS. Na podstawie badań, przeprowadzonych w oparciu o własne oprogramowanie symulujące pracę systemu i kanał, dokonano porównana nowego mechanizmu z mechanizmem zaproponowany w specyfikacji systemu UMTS, pracującym z częstotliwością 1500 rozk/sek. Ponadto...
-
Application of the Bodner-Partom constitutive equations for modelling of the technical fabric Valmex used for the hanging roof of the Forest Opera in Sopot
PublicationThe study of an inelastic properties of the technical fabric Valmex used for 20 years as the roof structure of the Forest Opera in Sopot (Poland) is presented. The uniaxial tensile laboratory tests with constant strain rate have been conducted and analysed. Parameters of the Bodner-Partom constitutive model have been identified and verified by numerical simulations. Two approaches of the parameters identification have been proposed:...
-
A Stand for Measurement and Prediction of Scattering Properties of Diffusers
PublicationIn this paper we present a set of solutions which may be used for prototyping and simulation of acoustic scattering devices. A system proposed is capable of measuring sound field. Also a way to use an open source solution for simulation of scattering phenomena occurring in proximity of acoustic diffusers is shown. The result of our work are measurement procedure and a prototype of the simulation script based on FEniCS - an open source...
-
Application of wavelength division multiplexing in sensor networks
PublicationOver the past few years the need to acquire data on various parameters from a number of sensors grew. The need that led to the development of a network of sensors which enables simultaneous control and measurement in a wide range of applications. The aim of this article is to discuss a possibility of connecting a variety of sensors in a network that would utilize WDM technology. Wavelength Division Multiplexing is commonly used...
-
Vibration of the bridge under moving singular loads - theoretical formulation and numerical solution
PublicationThe paper presents the results of the numerical analysis of a simple vehicle passing over a simply supported bridge span. The bridge is modelled by a Euler-Bernoulli beam. The vehicle is modelled as a linear, visco-elastic oscillator, moving at a constant speed. The system is described by a set of differential equations of motion and solved numerically using the Runge-Kutta algorithm. The results are compared with the solution...
-
Compensation Topologies in IPT Systems: Standards, Requirements, Classification, Analysis, Comparison and Application
PublicationWireless power transfer devices are becoming more relevant and widespread. Therefore, an article is devoted to a review, analysis and comparison of compensation topologies for an inductive power transfer. A new classification of topologies is developed. A lot of attention is paid to the problems of the physical fundamentals of compensation work, standards, safety, and five main topology requirements. It is determined, that topologies...
-
Progress towards a unified approach to entanglement distribution
PublicationEntanglement distribution is key to the success of secure communication schemes based on quantum mechanics, and there is a strong need for an ultimate architecture able to overcome the limitations of recent proposals such as those based on entanglement percolation or quantum repeaters. In this work we provide a broad theoretical background for the development of such technologies. In particular, we investigate the question of whether...
-
A global multinational survey of cefotaxime-resistant coliforms in urban wastewater treatment plants
PublicationThe World Health Organization Global Action Plan recommends integrated surveillance programs as crucial strategies for monitoring antibiotic resistance. Although several national surveillance programs are in place for clinical and veterinary settings, no such schemes exist for monitoring antibiotic-resistant bacteria in the environment. In this transnational study, we developed, validated, and tested a low-cost surveillance and...
-
Photosensitization of TiO2 and SnO2 by Artificial Self-Assembling Mimics of the Natural Chlorosomal Bacteriochlorophylls
PublicationOf all known photosynthetic organisms, the green sulfur bacteria are able to survive under the lowest illumination conditions due to highly efficient photon management and exciton transport enabled by their special organelles, the chlorosomes, which consist mainly of self-assembled bacteriochlorophyll c, d, or e molecules. A challenging task is to mimic the principle of self-assembling chromophores in artificial light-harvesting...
-
Data, Information, Knowledge, Wisdom Pyramid Concept Revisited in the Context of Deep Learning
PublicationIn this paper, the data, information, knowledge, and wisdom (DIKW) pyramid is revisited in the context of deep learning applied to machine learningbased audio signal processing. A discussion on the DIKW schema is carried out, resulting in a proposal that may supplement the original concept. Parallels between DIWK pertaining to audio processing are presented based on examples of the case studies performed by the author and her collaborators....
-
EvOLAP Graph – Evolution and OLAP-Aware Graph Data Model
PublicationThe objective of this paper is to propose a graph model that would be suitable for providing OLAP features on graph databases. The included features allow for a multidimensional and multilevel view on data and support analytical queries on operational and historical graph data. In contrast to many existing approaches tailored for static graphs, the paper addresses the issue for the changing graph schema. The model, named Evolution...
-
Categorization of Cloud Workload Types with Clustering
PublicationThe paper presents a new classification schema of IaaS cloud workloads types, based on the functional characteristics. We show the results of an experiment of automatic categorization performed with different benchmarks that represent particular workload types. Monitoring of resource utilization allowed us to construct workload models that can be processed with machine learning algorithms. The direct connection between the functional...
-
Rozkład naprężeń mechanicznych w łyżce o szerokości 500 mm, przeznaczonej do koparki podsiębiernej
PublicationW artykule zaprezentowano optymalizację kształtu łyżki koparki przedsiębiernej z wykorzystaniem analizy wytrzymałościowej. Analizę oparto na trójwymiarowym modelu konstrukcji łyżki z zastosowaniem metody elementów skończonych (MES). Opracowanie wspomnianej metody pozwoliło na modyfikację konstrukcji łyżki, która dała w efekcie obniżenie naprężeń złożonych w newralgicznych obszarach konstrukcji łyżki. Przedstawiona analiza okazała...
-
Flora i fauna w sztuce cystersów Pomorza Gdańskiego. Flora and fauna in the art of Pomerelian Cistercians.
PublicationW sztuce cystersów pomorskich bardzo często spotyka się motywy odnoszące się do flory i fauny. W okresie średniowiecza miały one najczęściej znaczenie symboliczne, związane ze Starym i Nowym Testamentem. Ich głównym zadaniem było przypomnienie zakonnikom o miłosierdziu Pańskim oraz treści związanych z tymi fragmentami życia Jezusa, które są wskazówkami jak powinni żyć chrześcijanie. Sygnalizowano też konieczność wykazywania stałej...
-
Assessment of Trace Metals Leaching During Rainfall Events from Building Rooftops with Different Types of Coverage – Case Study
PublicationRunoff water is an important medium transporting various types of pollution originating from the atmosphere and washed out from roofing materials. The study presents a quality assessment of runoff from different roofs in the context of trace metal concentrations. The analysed rooftops were covered with copper, tar paper and ceramic tile. The quality of the rain water collected at the same time satisfies the demands of the first...
-
Zmodernizowany most Łazienkowski w Warszawie – analizy z wykorzystaniem modelu numerycznego MES
PublicationW artykule przedstawiono proces modelowania statycznego przęseł mostu Łazienkowskiego w Warszawie, który został poddany odbudowie po pożarze 14 lutego 2015 r. Sprawdzające obliczenia numeryczne wykonano w związku z badaniami konstrukcji podczas próbnego obciążenia. Przeprowadzono weryfikację obliczeń projektowych i zaprojektowano próbne obciążenie. Podsumowano wyniki analizy i badań. Dodatkowo opisano nową, stalową konstrukcję...
-
Analysis of unsteady pipe flow using the modified finite element method
PublicationW pracy przedstawiono rozwiązanie równania przepływu nieustalonego zmodyfikowaną metodą elementów skończonych. Podejście to prowadzi do 6-punktowego schematu niejawnego z dwoma parametrami wagowymi. Analiza dokładności wykonana metodą równania zmodyfikowanego wykazała, że zaproponowany schemat zapewnia wyższą dokładność rozwiązania niż inne schematy. Porównanie wyników obliczeń z wynikami eksperymentu fizycznego wskazuje, że ich...
-
Wyszukiwanie obrazów medycznych na podstawie ich treści.
PublicationPrzedstawiono nowe metody opisu i wyszukiwania obrazów na podstawie ich treści. Zaproponowano schemat ekstrakcji regionów oraz generacji ich opisów z zastosowaniem kodów długości serii. W opracowanym systemie zaprojektowano i zaimplementowano możliwość definiowania zapytań do baz danych uwzględniając: właściwości i parametry regionu (deskryptory intensywności, deskryptory tekstury, deskryptory kształtu) oraz relacji przestrzennych...
-
Analiza stanu technicznego hali Olivia po 40 latach użytkowania
PublicationW artykule przedstawiono stan techniczny konstrukcji hali ''Olivia'' w Gdańsku. Obiekt ten, wybudowany 40 lat temu, znajduje się obecnie w stanie przedawaryjnym. Stalowe, sprężone dźwigary dachowe są unikalnym nie tylko w skali kraju, rozwiązaniem konstrukcyjnym. Przeprowadzono szczegółowy przegląd techniczny całego obiektu, nie wyłączając kanałów kablowych. Z uwagi na nietypowy schemat statyczny dźwigarów dachowych, wykonano 2...