Filters
total: 2013
-
Catalog
- Publications 1674 available results
- Journals 55 available results
- Conferences 32 available results
- Publishing Houses 1 available results
- People 59 available results
- Projects 4 available results
- e-Learning Courses 19 available results
- Events 4 available results
- Open Research Data 165 available results
displaying 1000 best results Help
Search results for: AD HOC NETWORK
-
Waves in a short cable at low frequencies, or just hand-waving? What does physics say? (Invited paper)
PublicationWe address the question of low-frequency signals in a short cable, which are often considered as waves in engineering calculations. Such an assumption violates several laws of physics, but exact calculations can be carried out via linear network theory.
-
Why the Solvation Water around Proteins Is More Dense than Bulk Water
PublicationThe main aim of this work is to propose a rational explanation of the commonly observed phenomenon of increasing water density within solvation shell of proteins. We have observed that the geometry of the water–water hydrogen bond network within solvation layer differs from the one in bulk water, and it is the result of interactions of water molecules with protein surface. Altered geometry of the network reflects changes in the...
-
Why the solvation water around proteins is more dense than bulk water
PublicationThe main aim of this work is to propose a rational explanation of commonly observed phenomenon of increasing water density within solvation shell of proteins. We have observed that geometry of the water-water hydrogen bond network within solvation layer differs from the one in bulk water and it is the effect of interactions of water molecules with protein surface. Altered geometry of the network reflects changes in the structure...
-
Service and Path Discovery Extensions for Self-forming IEEE 802.11s Wireless Mesh Systems
PublicationWith the rapid growth of the quantity and capabilities of end-user electronic devices, both stationary and mobile, they are employed in increasing number of applications. In this situation, wireless network technologies begin to play a crucial role as networks access technologies, as cable-based solutions tend to be of limited utility in case of easily portable or mobile devices. Resulting development of wireless technologies reached...
-
A Development of a Capacitive Voltage Divider for High Voltage Measurement as Part of a Combined Current and Voltage Sensor
PublicationThis article deals with the development of capacitive voltage divider for high voltage measurements and presents a method of analysis and optimization of its parameters. This divider is a part of a combined voltage and current sensor for measurements in high voltage power networks. The sensor allows continuous monitoring of the network distribution status and performs a quick diagnosis and location of possible network failures....
-
How does institutional and natural social support shape the beliefs about psychological help among policemen?
PublicationEffectiveness of social support mechanisms results from interacting subjective factors (beliefs about help from others) and context (social network available). Organized institutional support and perception of natural support reduce barriers in obtaining psychological help.
-
Joanna Wolszczak-Derlacz dr hab.
PeopleI am an Associate Professor at Gdańsk University of Technology, Faculty of Management and Economics. I gained my PhD in July 2006 for which I received the Polish Prime Ministry’s Award for the outstanding doctoral thesis. Between 2007 and 2008, I was a beneficiary of the Max Weber Fellowship at the European University Institute in Florence, Italy. I conducted part of my research at the Katholieke Universiteit Leuven, Belgium...
-
Accuracy of marine gravimetric measurements in terms of geodetic coordinates of land reference benchmark
PublicationThe article presents how the values of (3D) coordinates of land reference points affect the results of gravimetric measurements made from the ship in sea areas. These measurements are the basis for 3D maritime inertial navigation, improving ships' operational safety. The campaign verifying the network absolute point coordinates used as a reference point for relative marine gravity measurements was described. The obtained values...
-
Logical Interface for Soft Handover – an effective scheme of handovers in Proxy Mobile IPv6
PublicationMultimedia services are currently commonly available on mobile devices. Due to networks' convergence and migration to all-IP networks, mobility management at network layer is required. Moreover, nowadays it is popular to equip mobile devices with more than one wireless interface. Thus, soft handovers can be implemented, which means that an existing connection is removed after a new one is established. Usage of the Logical Interfaces...
-
Measures of region failure survivability for wireless mesh networks
PublicationWireless mesh networks (WMNs) are considered as a promising alternative to wired local, or metropolitan area networks. However, owing to their exposure to various disruptive events, including natural disasters, or human threats, many WMN network elements located close to the failure epicentre are frequently in danger of a simultaneous failure, referred to as a region failure. Therefore, network survivability, being the ability...
-
Analysis and design improvement of high class roads’ arched sections in Poland
PublicationAlthough Polish road network standards, in particular higher classes of roads are improving dynamically the number of fatalities on the network is still higher that EU’s average. Ensuring road safety and high maintaining standards is a complex issue and one that poses a major challenge for all road authorities. Road accidents at high speed roads characterize specially serious material and social consequences, thus research into...
-
The Use of Gravimetric Measurements to Determine the Orthometric Height of the Benchmark in the Port of Gdynia
PublicationThis paper contains a description of the technology used to make gravimetric measurements of the height of a reference point located in the Port of Gdynia, Poland. Measurements were made using a CG-5 gravimeter manufactured by LaCoste & Romberg Scintrex Inc., and determinations of position used a Leica Viva GS15 receiver integrated with a network of HxGN SmartNet GNSS reference stations. The measuring methodology required gravimeter...
-
Throughput-Coverage Characteristics for Soft and Partial Frequency Reuse in the LTE Downlink
PublicationThe paper presents results of simulation and evaluation of throughput-coverage characteristics for the OFDMA-based LTE network with Soft Frequency Reuse or Partial Frequency Reuse. Firstly, simulation results of throughput characteristics for a single user connection are presented, which allow the evaluation of the stability and availability of bit rate achieved in different areas of a cell. Secondly, the capacity characteristics...
-
Empirical analyses of robustness of the square Msplit estimation
PublicationThe paper presents Msplit estimation as an alternative to methods in the class of robust M-estimation. The analysis conducted showed that Msplit estimation is highly efficient in the identification of observations encumbered by gross errors, especially those of small or moderate values. The classical methods of robust estimation provide then unsatisfactory results. Msplit estimation also shows high robustness to single gross errors...
-
Performance Models of a Multidomain IMS/NGN Service Stratum
PublicationThis paper quantifies call processing performance (CPP) of a multidomain IMS/NGN architecture, which was proposed to deliver current and future telecommunication services with strict quality requirements, independently of the transport network technologies. A realistic simulation model is used as a reference for evaluation of the analytical results, in which vari-ous types of queuing systems are applied to model the opera-tion...
-
Identification of Unstable Reference Points and Estimation of Displacements Using Squared Msplit Estimation
PublicationThe article presents a new version of the method for estimating parameters in a split functional model, which enables the determination of displacements of geodetic network points with constrained datum. The main aim of the study is to present theoretical foundations of Msplit CD estimation and its basic properties and possible applications. Particular attention was paid to the efficacy of the method in the context of geodetic...
-
Tagged images with bees
Open Research DataImages taken from bee hive with tagged bees. The images are prepared for training yolo5 deep neural network (supplied with the data).
-
Number of own bank branches (2017)
Open Research DataThe number of traditional bank branches is decreasing. As can be seen from the data presented in the table below, over the year (2016-2017), the network of bank branches in Poland decreased by over half a thousand (currently the total number of traditional bank branches, excluding partner branches, amounts to nearly 6 thousand). None of the 20 largest...
-
Video of LEGO bricks on conveyor belt - flags and signs
Open Research DataThe set contains videos of LEGO bricks (flags and signs) moving on a white conveyor belt. The images were prepared for training neural network for recognition of LEGO bricks. The bricks were separated as much as possible and in most cases they should not overlap. The images were taken from different sides by stationary camera located over the final...
-
Metody doboru miejsc zainstalowania zasobników energii w sieciach elektroenergetycznych niskiego napięcia
PublicationW związku z rosnącą liczbą źródeł odnawialnych przyłączanych do sieci niskiego napięcia (nn) jakość energii elektrycznej w tej sieci ulega pogorszeniu. Jedną z metod jej poprawiania jest instalowanie zasobników energii, tj. baterii akumulatorów, superkondensatorów czy kół zamachowych. Zasobniki energii są w stanie złagodzić dobową zmienność obciążenia, skompensować moc bierną i wyższe harmoniczne oraz zmniejszyć asymetrię obciążenia...
-
Beata Krawczyk-Bryłka dr
PeoplePsycholog, doktor nauk humanistycznych w dziedzinie zarządzania, adiunkt w Katedrze przedsiębiorczości. 2018 - 2021: Kierownik projektu NCN: „Efektuacyjny model zespołu przedsiębiorczego. Jak działają przedsiębiorcze zespoły odnoszące sukces" od 2016: Quality Standards Lead filaru People management & personal development na studiach MBA Politechniki Gdańskiej 2008 – 2012: Prodziekan ds kształcenia Wzydziału Zarządzania i Ekonomii...
-
Struktury sieci transportu zbiorowego w miastach
PublicationPotrzeby przewozowe mieszkańców miast powinny być zaspokajane poprzez dopasowaną i sprawnie funkcjonującą sieć transportu zbiorowego. Planując sieć i decydując się jednocześnie na jej sposób funkcjonowania istotnym jest uwzględnienie podstawowych postulatów przewozowych mieszkańców. Ostateczny kształt tej sieci wynika jednak z dodatkowych czynników zarówno infrastrukturalnych, ekonomicznych, jak i wielu innych. Celem niniejszego...
-
Nitrate and nitrite silver complexes with weakly coordinating nitriles
PublicationSimple system of weak nitrile ligands and silver nitrite/nitrate allowed the formation and isolation of coordination compounds of diverse nuclearity and dimensionality. The extension of the network does not enhance the luminescent properties of the ligands however it gives rise to the new MLCT bands in the visible region.
-
Application of Feed Forward Neural Networks for Modeling of Heat Transfer Coefficient During Flow Condensation for Low and High Values of Saturation Temperatur
PublicationMost of the literature models for condensation heat transfer prediction are based on specific experimental parameters and are not general in nature for applications to fluids and non-experimental thermodynamic conditions. Nearly all correlations are created to predict data in normal HVAC conditions below 40°C. High temperature heat pumps operate at much higher parameters. This paper aims to create a general model for the calculation...
-
Open extensive IoT research and measurement infrastructure for remote collection and automatic analysis of environmental data.
PublicationInternet of Things devices that send small amounts of data do not need high bit rates as it is the range that is more crucial for them. The use of popular, unlicensed 2.4 GHz and 5 GHz bands is fairly legally enforced (transmission power above power limits cannot be increased). In addition, waves of this length are very diffiult to propagate under field conditions (e.g. in urban areas). The market response to these needs are the...
-
GPS-derived height changes in diurnal and sub-diurnal timescales
PublicationThis paper describes the research concerning precise short-time GPS solutions conducted in the Centre of Applied Geomatics, Military University of Technology, Warsaw, Poland. The data from ASG-EUPOS (Polish Active Geodetic Network) was processed using Bernese 5.0 software and EPN (EUREF Permanent Network) standards and models. In this study, the adapted 3-hour observation window is shifted every hour for obtaining hourly geocentric...
-
Deep Learning Optimization for Edge Devices: Analysis of Training Quantization Parameters
PublicationThis paper focuses on convolution neural network quantization problem. The quantization has a distinct stage of data conversion from floating-point into integer-point numbers. In general, the process of quantization is associated with the reduction of the matrix dimension via limited precision of the numbers. However, the training and inference stages of deep learning neural network are limited by the space of the memory and a...
-
The reliability of tree and star networks
PublicationThis paper investigated the reliability of tree and star networks. Following measures of network reliability are assumed: the expected number of nodes, that can communicate with the central node; the expected number of node pairs, that are connected by a path through the central node; the expected number of node pairs communicating.
-
Application of the neural networks for developing new parametrization of the Tersoff potential for carbon
PublicationPenta-graphene (PG) is a 2D carbon allotrope composed of a layer of pentagons having sp2- and sp3-bonded carbon atoms. A study carried out in 2018 has shown that the parameterization of the Tersoff potential proposed in 2005 by Ehrhart and Able (T05 potential) performs better than other potentials available for carbon, being able to reproduce structural and mechanical properties of the PG. In this work, we tried to improve the...
-
Mechanizmy bezpieczeństwa transmisji w systemie netBaltic
Publicationartykule zaprezentowano założenia dotyczące zabezpieczania węzłów sieci realizowanej w ramach systemu netBaltic. Ze względu na dużą różnorodność rozważanych mechanizmów komunikacyjnych architektura bezpieczeństwa została podzielona na kilka elementów – infrastrukturę klucza publicznego (PKI), bezpieczeństwo systemowe węzłów, zabezpieczanie komunikacji w modelu samoorganizującej wieloskokowej sieci kratowej, a także sieci niewrażliwej...
-
Geodesy measurement techniques as an enrichment of archaeological research workflow
PublicationUse of geodesy techniques is widespread in different fields of science. Especially in such an emerging and dynamic branch of science as archaeology. Warsaw Institute of Archaeology, conducts many archaeological expeditions, among the others Polish-Georgian archaeological expedition in Gonio, where ancient Roman Bath has been discovered and excavated. Gonio is located in Adjara, Georgia, placed on the Black Sea coast. Fortress...
-
Postępy w rozwoju standardu IEEE 802.11 i jego zastosowań Część II: Nowe obszary zastosowań i nowe koncepcje pracy sieci WiFi
PublicationArtykuł stanowi kontynuację rozważań, podjętych w zeszycie nr 11 z 2016 r. PTiWT [1], na temat rozwoju standardu łEEE 802.11 , ukierunkowanego na zwiększanie szybkości przekazu i przekraczanie gigabitowej granicy przepływności łącza. Wskazano tam na modyfikacje i nowe mechanizmy implementowane w warstwie fizycznej i podwarstwie MAC standardów IEEE 802.11 n, IEEE 802.11 ac oraz IEEE 802.11 ad, mające istotny wpływ zarówno na wzrost...
-
Atmospheric degradation mechanism of anthracene initiated by OH•: A DFT prediction
PublicationDensity functional theory (DFT) calculations at the M06-2X/def2-TZVP level have been employed to investigate the atmospheric oxidation mechanism of anthracene (ANT) initiated by HO•. Direct hydrogen atom abstraction from the ANT using HO• takes place hardly at ambient conditions while the addition of HO• to the C1, C2, and C4 sites are thermodynamically and kinetically more advantageous. The addition reactions are controlled by...
-
Starter for Voltage Boost Converter to Harvest Thermoelectric Energy for Body-Worn Sensors
PublicationThis paper examines the suitability of selected configurations of ultra-low voltage (ULV) oscilla-tors as starters for a voltage boost converter to harvest energy from a thermoelectric generator (TEG). Important properties of particularly promising configurations, suitable for on-chip imple-mentation are compared. On this basis, an improved oscillator with a low startup voltage and a high output voltage swing is proposed. The applicability...
-
Ultra-Compact SIRC-Based Self-Triplexing Antenna with High Isolation
PublicationAn ultra-compact self-triplexing antenna realized on a substrate-integrated rectangular cavity (SIRC) is discussed in this study. The proposed structure employs two L-shaped slots and an in-verted U-shaped slot to radiate at three independent operating frequency bands. Three 50-ohm microstrip feed lines are used to excite the radiation in these slots. The operating frequency is individually tuned using the slot size. The slot placement...
-
Mohammad Hossein Ghaemi dr inż.
PeopleMohammad Hossein Ghaemi Mohammad Hossein Ghaemi (1967), is an Assistant Professor at the Faculty of Mechanical Engineering and Ship Technology - WIMiO (till 2020: Faculty of Ocean Engineering and Ship Technology), Department of Automatics and Marine Energy Engineering. He studied first at Tehran University, where was graduated in the field of Mechanical Engineering (Solid Mechanics). Then he received his MSc degree in the area...
-
Wireless systems of threats monitoring
PublicationThe concept of wireless system of threats monitoring with self-organizing network of multipurpose data transfer nodes are presented. Two practical applications of this system are also presented. The first of these is the Global Wireless Monitoring System for Containers, and the second is the Mobile Monitoring System for Gas Air Pollution Measurements.
-
Wireless Systems of Threats Monitoring
PublicationConcept of wireless system of threats monitoring with self-organizing network of multipurpose data transfer nodes are presented. Two practical applications of this system are also presented. The first of these is the Global Wireless Monitoring System for Containers and the second is the Mobile Monitoring System for Gas Air Pollution Measurements.
-
Wireless systems of threats monitoring
PublicationThe concept of wireless system of threats monitoring with self-organizing network of multipurpose data transfer nodes are presented. Two practical applications of this system are also presented. The first of these is the Global Wireless Monitoring System for Containers, and the second is the Mobile Monitoring System for Gas Air Pollution Measurements.
-
Architektura bezpieczeństwa systemu netBaltic
PublicationW artykule zaprezentowano założenia dotyczące zabezpieczania węzłów sieci realizowanej w ramach systemu netBaltic. Ze względu na dużą różnorodność rozważanych mechanizmów komunikacyjnych architektura bezpieczeństwa została podzielona na kilka elementów – infrastrukturę klucza publicznego (PKI), bezpieczeństwo systemowe węzłów, zabezpieczanie komunikacji w modelu samoorganizującej wieloskokowej sieci kratowej, a także sieci niewrażliwej...
-
Evaluation of ASON/GMPLS Connection Control Servers Performance
PublicationPerformance aspects have always been very important in telecommunications, especially in control elements. That problem also regards ASON/GMLPS network, which is one of the propositions for Next Generation Network (NGN) transport stratum. In this paper we investigate performance of ASON/GMPLS Connection Control Servers (CCSs) in laboratory testbed, which architecture and operation are also described. In order to evaluate the performance...
-
Extensions of ETSI performance measurements methodology for statistical results analysis =Rozszerzenia metodologii pomiarów wydajności zaproponowanej przez ETSI przy statystycznej analizy wyników
PublicationNext Generation Network (NGN) architecture was proposed by International Telecommunication Union Telecommunication Standardization Sector (ITU-T) to deliver telecommunication services satisfying the needs of modern society for an access to information. The core of NGN service stratum are IP Multimedia Subsystem (IMS) elements acting as service controls units. To assess performance of IMS components, European Telecommunications...
-
Service-based Resilience for Embedded IoT Networks
PublicationEmbedded IoT networks are the backbone of safety-critical systems like smart factories, autonomous vehicles, and airplanes. Therefore, resilience against failures and attacks should be a prior concern already in their design stage. In this study, we introduce a service-based network model as an MILP optimization problem for the efficient deployment of a service overlay to the embedded network by meeting QoS and resilience requirements....
-
A survey of strategies for communication networks to protect against large-scale natural disasters
PublicationRecent natural disasters have revealed that emergency networks presently cannot disseminate the necessary disaster information, making it difficult to deploy and coordinate relief operations. These disasters have reinforced the knowledge that telecommunication networks constitute a critical infrastructure of our society, and the urgency in establishing protection mechanisms against disaster-based disruptions. Hence, it is important...
-
Spatial pattern of ASG-EUPOS sites
PublicationThe article presents the spatial pattern analysis of the ASG-EUPOS permanent GNSS stations in Poland. Using different methods and tools (nearest neighbour, Riplay’s K-function, morphology of Thiessen polygons) we proved that the station distribution model changes within scales. At short distances up to 65 km, which are typical lengths in the network, stations are irregularly dispersed. Increasing this distance to 130 km and over...
-
INFLUENCE OF DATA NORMALIZATION ON THE EFFECTIVENESS OF NEURAL NETWORKS APPLIED TO CLASSIFICATION OF PAVEMENT CONDITIONS – CASE STUDY
PublicationIn recent years automatic classification employing machine learning seems to be in high demand for tele-informatic-based solutions. An example of such solutions are intelligent transportation systems (ITS), in which various factors are taken into account. The subject of the study presented is the impact of data pre-processing and normalization on the accuracy and training effectiveness of artificial neural networks in the case...
-
CNN Architectures for Human Pose Estimation from a Very Low Resolution Depth Image
PublicationThe paper is dedicated to proposing and evaluating a number of convolutional neural network architectures for calculating a multiple regression on 3D coordinates of human body joints tracked in a single low resolution depth image. The main challenge was to obtain a high precision in case of a noisy and coarse scan of the body, as observed by a depth sensor from a large distance. The regression network was expected to reason about...
-
Dynamic charging of electric buses
PublicationDespite the continuous development of electrochemical battery technology and the multitude of electric buses on offer, it is still not possible to exploit electric buses in urban transport on an all-day basis without the necessity of charging them. It is therefore necessary to build point-to-point contact charging stations or induction charging stations at the terminals. This results in substantial financial outlays connected with...
-
Leader election for anonymous asynchronous agents in arbitrary networks
PublicationWe consider the problem of leader election among mobile agents operating in an arbitrary network modeled as an undirected graph. Nodes of the network are unlabeled and all agents are identical. Hence the only way to elect a leader among agents is by exploiting asymmetries in their initial positions in the graph. Agents do not know the graph or their positions in it, hence they must gain this knowledge by navigating in the graph...
-
Effect of the welding environment and storage time of electrodes on the diffusible hydrogen content in deposited metal
PublicationIn the study the glycerin displacement method was used for determination of diffusible hydrogen content in deposited metal. Specimens were welded in the air and in the water with covered rutile electrodes. The first part of the specimens was made immediately after opening the package of the electrodes. The electrodes were then stored in opened packages in laboratory conditions that allowed for contact with the air for three years....