Search
Filters
total: 10077
-
Catalog
- Publications 8427 available results
- Journals 489 available results
- Conferences 252 available results
- People 362 available results
- Inventions 1 available results
- Projects 15 available results
- Research Teams 1 available results
- Research Equipment 2 available results
- e-Learning Courses 286 available results
- Events 12 available results
- Open Research Data 230 available results
displaying 1000 best results Help
Search results for: TIME-VARYING SYSTEMS
-
2024/2025 Enterprise Information Systems
e-Learning Courses -
Broadband fiber optic communication systems
e-Learning Courses -
On the existence of homoclinic type solutions of inhomogenous Lagrangian systems
PublicationWe study the existence of homoclinic type solutions for a class of inhomogenous Lagrangian systems with a potential satisfying the Ambrosetti-Rabinowitz superquadratic growth condition and a square integrable forcing term. A homoclinic type solution is obtained as a limit of periodic solutions of an approximative sequence of second order differential equations.
-
THIRD-ORDER EXPONENTIAL INTEGRATOR FOR LINEAR KLEIN–GORDON EQUATIONS WITH TIME AND SPACE-DEPENDANT MASS
PublicationAllowing for space- and time-dependance of mass in Klein–Gordon equations re- solves the problem of negative probability density and of violation of Lorenz covariance of interaction in quantum mechanics. Moreover it extends their applicability to the domain of quantum cosmology, where the variation in mass may be accompanied by high oscillations....
-
THIRD-ORDER EXPONENTIAL INTEGRATOR FOR LINEAR KLEIN–GORDON EQUATIONS WITH TIME AND SPACE-DEPENDANT MASS
PublicationAllowing for space- and time-dependance of mass in Klein–Gordon equations re- solves the problem of negative probability density and of violation of Lorenz covariance of interaction in quantum mechanics. Moreover it extends their applicability to the domain of quantum cosmology, where the variation in mass may be accompanied by high oscillations....
-
Comparative Analysis of Two Polish Hyperbolic Systems AEGIR and JEMIOLUSZKA
PublicationGlobal Navigation Satellite System (GNSS) is seen by terrorists or hostile countries as a high value target. Volpe Center report contains the following statement: “During the course of its development for military use and more recent extension to many civilian uses, vulnerabilities of Global Navigation Satellite Systems (GNSS) – in the United States the Global Positioning System (GPS) – have become apparent. The vulnerabilities...
-
Design of radio communication systems for unmanned transport applications
PublicationIn the paper the principle of OFDMA-based radio communication systems design for unmanned transport applications is presented. The concept of system radio interface is analysed and its basic parameters proposal are considered. In the last part of the paper some air interface characteristics useful for optimization of throughput and system capacity are considered.
-
Time variable gain for long range sonar with chirp sounding signal
PublicationThe main purpose of applaying Time Variable Gain (TVG) in active sonars with digital signal processing is to reduce dynamic range of echo signal and adapt it to the dynamic range of the analogue to digital conversion. With high transmission losses level, the dynamic range of the input signal in long range sonars can be very high and even exceed 200dB. When chirp sounding signals with matched filtration are used, sonars can raech...
-
Two-state dynamics for replicating two-strand systems
PublicationDynamika dwustanowa została zastosowana do opisów układów dwuniciowych, analogicznych do DNA.
-
Visual content representation and retrieval for Cognitive Cyber Physical Systems
PublicationCognitive Cyber Physical Systems have gained significant attention from academia and industry during the past few decade. One of the main reasons behind this interest is the potential of such technologies to revolutionize human life since they intend to work robustly under complex visual scenes, which environmental conditions may vary, adapting to a comprehensive range of unforeseen changes, and exhibiting prospective behavior...
-
A testing method of analog parts of mixed-signal electronic systems equipped with the IEEE1149.1 test bus
PublicationA new solution of the JTAG BIST for testing analog circuits in mixed-signal electronic microsystems controlled by microcontrollers and equipped with the IEEE1149.1 bus is presented. It is based on a new fault diagnosis method in which an analog circuit is stimulated by a buffered signal from the TMS line, and the time response of the circuit to this signal is sampled by the ADC equipped with the JTAG. The method can be used for...
-
Expert systems in quality control of manufacturing processes
PublicationThe paper deals with quality control in conditions of computer integrated manufacturing (CIM). It shows that quality of material stream items have to be analyzed on every stage of manufacturing process. Collecting and analyzing quantity of data with usage of expert systems make it possible to create a system for coordination of cell's work. The system contains error recovery algorithm and adaptive control subsystem based on fuzzy...
-
Solutions of inverter systems in Shore-to-Ship Power supply systems
Publication -
Impact of Spatial Noise Correlation on Bearing Accuracy in DIFAR Systems
PublicationDIFAR type underwater passive systems are one of the more commonly used tools for detecting submarines. At the design stage, which usually uses computer simulations, it is necessary to generate acoustic noise of the sea. It has been shown that correlating noise significantly reduces these errors compared to the assumption that noise is uncorrelated. In addition, bearing errors have been shown to be the same in systems with a commonly...
-
Solutions of Power Electronics Converter for the Shore - to - Ship Power Systems
PublicationW artykule poruszono tematykę zasilania statków zacumowanych w porcie z lądowej sieci elektroenergetycznej poprzez wykorzystanie nowoczesnych konstrukcji przekształtników energoelektronicznych. Zaproponowano budowę sieci dystrybucyjnej prądu stałego, przewoźnej platformy zasilającej oraz zastosowanie zasobników energii
-
Multidimensional legacy aspects of modernizing web based systems
PublicationPublikacja porusza zagadnienia technik modernizacji tzw. legacy systems mających zastosowanie w cyklach życia oprogramowania. Przedmiotem dyskusji jest także studium przypadku Endoscopy Recommender System. Ponadto rozważany jest wpłw zmian wymagań, platform, standardów oraz strategii rozwoju oprogramowania na status legacy aplikacji webowych.
-
BIOGAS PRODUCTION FROM BAKERY WASTES -DYNAMICS, RETENTION TIME AND BIOGAS POTENTIAL
PublicationThis paper presents results of bakery-waste methane-fermentation. The scope of the study covers the determination of basic physicochemical parameters, process dynamics and retention time as well as biogas composition and biogas efficiency. Methane fermentation process was carried out in accordance with German Standard DIN 38414 S8 and under condition of 38°C. Conclusion: bakery wastes have big potential for biogas production.
-
Innovations in Wastewater Treatment: Harnessing Mathematical Modeling and Computer Simulations with Cutting-Edge Technologies and Advanced Control Systems
PublicationThe wastewater treatment landscape in Central Europe, particularly in Poland, has undergone a profound transformation due to European Union (EU) integration. Fueled by EU funding and rapid technological advancements, wastewater treatment plants (WWTPs) have adopted cutting-edge control methods to adhere to EU Water Framework Directive mandates. WWTPs contend with complexities such as variable flow rates, temperature fluctuations,...
-
How to Design Affect-aware Educational Systems – the AFFINT Process Approach
PublicationComputer systems, that support learning processes, can adapt to the needs and states of a learner. The adaptation might directly address the knowledge deficits and most tutoring systems apply an adaptable learning path of that kind. Apart from a preliminary knowledge state, there are more factors, that influence education effectiveness and among those there are fluctuating emotional states. The tutoring systems may recognize or...
-
MERPSYS: An environment for simulation of parallel application execution on large scale HPC systems
PublicationIn this paper we present a new environment called MERPSYS that allows simulation of parallel application execution time on cluster-based systems. The environment offers a modeling application using the Java language extended with methods representing message passing type communication routines. It also offers a graphical interface for building a system model that incorporates various hardware components such as CPUs, GPUs, interconnects...
-
Periodic solutions of Lagrangian systems under small perturbations
PublicationIn this paper we prove the existence of mountain pass periodic solutions of a certain class of generalized Lagrangian systems under small perturbations. We show that the found periodic solutions converge to a periodic solution of the unperturbed system if the perturbation tends to 0. The proof requires to work in a rather unusual (mixed) Orlicz–Sobolev space setting, which bears several challenges.
-
Effect of MgSO4 nutrition on Theobroma cacao L. susceptibility to Phytophthora megakarya infection
PublicationA new strategy to reduce the severity of black pod disease (BPD) in T. cacao plants using MgSO4 nutrition was investigated. The dynamics of the tolerance to BPD of 18 susceptible T. cacao plantlets coming from the cross (♀SNK64 × ♂UPA14) was monitored during weekly (8 weeks) supply of MgSO4 into the soil. Prior to MgSO4 application, disease scores of the 18 plantlets (in six sets of three plantlets per set) were varying between...
-
Tuning of microstructure in engineered poly (trimethylene terephthalate) based blends with nano inclusion as multifunctional additive
PublicationImmiscible blends and their composites are heterogeneous and have variable morphology due to variation in mesophase regions. Tuning, i.e. controlling the phase dimension is important, thereof we report a “super-combo” effect of multiwalled carbon nanotubes (MWCNTs) in poly (trimethylene terephthalate)/polypropylene (PTT/ PP) blend system. MWCNTs act as a good reinforcing agent and compatibilizer in the otherwise immiscible PTT/...
-
Sustainable Urban Mobility Plans: implementation process and indicators to evaluate effects on physical activity
PublicationBackground: Active mobility and public transport increase physical activity (PA) levels. With varying intensity and effectiveness, European cities implement Sustainable Urban Mobility Plans (SUMPs) to spur transport-related PA. Therefore, we aim to examine drivers and barriers to SUMP implementation and assess its influence on PA across European cities. Methods: We screened policy reports to gain insights into SUMP implementation...
-
INVESTIGATIONS OF THE EMISSION CHARACTERISTICS OF A DUAL-FUEL GAS TURBINE COMBUSTION CHAMBER OPERATING SIMULTANEOUSLY ON LIQUID AND GASEOUS FUELS
PublicationT his study is dedicated to investigations of the working process in a dual-fuel low-emission combustion chamber for a floating vessel’s gas turbine. As the object of the research, a low-emission gas turbine combustion chamber with partial premixing of fuel and air inside the outer and inner radial-axial swirls was chosen. The method of the research is based on the numerical solution of the system of differential...
-
A Data-Driven Comparative Analysis of Machine-Learning Models for Familial Hypercholesterolemia Detection
PublicationThis study presents an assessment of familial hypercholesterolemia (FH) probability using different algorithms (CatBoost, XGBoost, Random Forest, SVM) and its ensembles, leveraging electronic health record data. The primary objective is to explore an enhanced method for estimating FH probability, surpassing the currently recommended Dutch Lipid Clinic Network (DLCN) Score. The models were trained using the largest Polish cohort...
-
Leather Waste Hydrolysation, Carbonization, and Microbial Treatment for Nitrogen Recovery by Ryegrass Cultivation
PublicationLeather waste contains up to 10% nitrogen (N); thus, combustion or gasification only for the energy recovery would not be rational, if safety standards are met. On the other hand, the chromium (Cr) content exceeding 5% in half of the waste stream (w/w) is too significant to be applied in agriculture. In this work, four acid hydrolysates from leather waste shavings, both wet-white free of Cr and wet-blue with Cr, were used: two...
-
Crafting an ultrashort workplace incivility scale and determining cutoffs for varied risk levels through item response theory
PublicationWorkplace incivility (WI), characterized by disrespectful or rude behavior in the workplace, is linked to poor mental health and overall well-being. The Workplace Incivility Scale (WIS) is a popular 7-item measure for assessing WI. There is a current need for an ultrashort conceptually clear version of the WIS. In addition, the cutoffs for varied at-risks of WI, requiring intervention, remains unknown. Using data from 426 employees...
-
Lignocellulosic waste biosorbents infused with deep eutectic solvents for biogas desulfurization
PublicationThis paper introduces an innovative method for treating biogas streams, employing lignocellulosic biosorbents infused with environmentally friendly solvents known as deep eutectic solvents (DES). The primary focus of this study was the elimination of volatile organosulfur compounds (VSCs) from model biogas. Biosorbents, including energetic poplar wood, antipka tree, corncobs, and beech wood, were used, each with varying levels...
-
PCR and real-time PCR assays to detect fungi of Alternaria alternata species
PublicationFungi of the Alternaria genus are mostly associated with allergic diseases. However, with a growing number of immunocompromised patients, these fungi, with A. alternata being the most prevalent one, are increasingly recognized as etiological agents of infections (phaeohyphomycoses) in humans. Nowadays, identification of Alternaria spp. requires their pure culture and is solely based on morphological criteria. Clinically, Alternaria...
-
Boundary value problems for dynamic equations of Volterra type on time scales
PublicationPraca dotyczy równań i nierówności dla problemów dynamicznych typu Volterry. Podano warunki dostateczne na istnienie ekstremalnych rozwiązań w obszarze ograniczonym przez dolne i górne rozwiązania. Praca zawiera również pewne uwagi dla konkretnych zagadnień różniczkowych i dyskretnych.
-
Topological Behaviour of Solutions of Vibro-Impact Systems in the Neighborhood of Grazing
PublicationThe grazing bifurcation is considered for the Newtonian model of vibro-impact systems. A brief review on the conditions, sufficient for the existence of a grazing family of periodic solutions, is given. The properties of these periodic solutions are discussed. A plenty of results on the topological structure of attractors of vibro-impact systems is known. However, since the considered system is strongly nonlinear, these attractors...
-
Sailing Vessel Routing Considering Safety Zone and Penalty Time for Altering Course
PublicationIn this paper we introduce new model for simulation sea vessel routing. Besides a vessel types (polar diagram) and weather forecast, travel security and the number of maneuvers are considered. Based on these data both the minimal travelling costs and the minimal processing time are found for different vessels and different routes. To test our model the applications SailingAssistance wad improved. The obtained results shows that...
-
Using an IEEE1149.1 Test Bus for Fault Diagnosis of Analog Parts of Electronic Embedded Systems
PublicationThe new solution of a BIST called the JTAG BIST for self-testing of analog parts of electronic embedded systems is presented in the paper. The JTAG BIST consists of the BCT8244A and SCANSTA476 integrated circuits of Texas Instruments controlled via the IEEE 1149.1 bus. The BCT8244A is a scan test device with octal buffers, and the SCANSTA476 is a 12-bit ADC with 8 analog input channels. Self-testing approach is based on the fault...
-
Cognitive memory for intelligent systems of decision-making, based on human psychology
PublicationA model of memory, which allows to expand the functionality of autonomous decision-making systems for robotic and human-system-interface purposes, is discussed. The model provides functions and features which make the prospective robotic and interfacing systems more human-like as well as more efficient in solving interactive issues.
-
ASCORBIC ACID IN POLYURETHANE SYSTEMS FOR TISSUE ENGINEERING
PublicationThe introduction of the paper was devoted to the main items of tissue engineering (TE) and the way of porous structure obtaining as scaffolds. Furthermore, the significant role of the scaffold design in TE was described. It was shown, that properly designed polyurethanes (PURs) find application in TE due to the proper physicochemical, mechanical and biological properties. Then the use of L-ascorbic acid (L-AA) in PUR systems for...
-
A novel architecture for e-learning knowledge assessment systems
PublicationIn this paper we propose a novel e-learning system, dedicated strictly to knowledge assessment tasks. In its functioning it utilizes web-based technologies, but its design differs radically from currently popular e-learning solutions which rely mostly on thin-client architecture. Our research proved that such architecture, while well suited for didactic content distribution systems is ill-suited for knowledge assessment products....
-
A novel architecture for e-learning knowledge assessment systems
PublicationIn this paper we propose a novel e-learning system, dedicated strictly to knowledge assessment tasks. In its functioning it utilizes web-based technologies, but its design differs radically from currently popular e-learning solutions which rely mostly on thin-client architecture. Our research proved that such architecture, while well suited for didactic content distribution systems is ill-suited for knowledge assessment products....
-
Opportunities and challenges for exploiting drones in agile manufacturing systems
PublicationDrones have become an advanced supply chain implementation instrument, especially in connecting warehouses to outlet points or even individual customers. However, their potential application in an intra-logistics framework has not been studied, let alone explored so far. Modeling and simulations in virtual environments can help explore and evaluate the opportunities for practical and profitable applications of drones in manufacturing...
-
Human Factors in designing the Instrumentation and Control Systems Important to Safety
PublicationThis work addresses selected aspects of human factors in designing the instrumentation and control (I&C) systems important to safety as a part of the functional safety management of industrial hazardous plants, in particular nuclear power plants. As it is known in such plants a concept of “defence in depth” (D-in-D) is widely applied and some layers of protection are designed with regard to functional safety (FS) concept given...
-
The cytoprotective role of antioxidants in mammalian cells under rapidly varying temperature, pressure and UV conditions during stratospheric balloon campaign
Publication -
Sinusoidal Alternating-Current Voltammetry and Metrological Properties of a Flat Voltammetric Electrode in the Time Domain
PublicationIn this paper there were analyzed metrological properties of a flat electrode used to mark ions with the method of sinusoidal alternating-current voltammetry in the situation where on its surface an electrochemical reversible reaction of oxidizing / reduction takes place. The result of the analysis conducted is that such a voltammetric electrode functions like a converter type I. Metrological properties of such an electrode in...
-
Fixed Pattern Noise Reduction and Linearity Improvement in Time-Mode CMOS Image Sensors
PublicationIn the paper, a digital clock stopping technique for gain and offset correction in time-mode analog-to-digital converters (ADCs) has been proposed. The technique is dedicated to imagers with massively parallel image acquisition working in the time mode where compensation of dark signal non-uniformity (DSNU) as well as photo-response non-uniformity (PRNU) is critical. Fixed pattern noise (FPN) reduction has been experimentally validated...
-
Time Delay Estimation in Two-Phase Flow Investigation Using the γ-Ray Attenuation Technique.
PublicationTime delay estimation is an important research question having many applications in a range of technologies. Measurement of a two-phase flow in a pipeline or an open channel using radioisotopes is an example of such application. For instance, the determination of velocity of dispersed phase in that case is based on estimation of the time delay between two stochastic signals provided by scintillation probes. The proper analysis...
-
Application of microturbines in CHP systems with reciprocating engines
PublicationThe analysis was carried out for Combined Heat and Power generation systems with micro-turbines power plants working on heat rejected from the reciprocating engine. The calculations were performed for GE Jerbacher engines of J320 GS- C05, J320 GS- C25 and J416 GS- B05 types. We considered different working media (both wet and dry fluids): water, ammonia, ethanol, methanol, methylacetylene (propyne), dimethyloether, sulphur dioxide,...
-
Delivery of Ancillary Services in Distribution Power Systems
PublicationOne of the technical and organizational challenges the power system faces in deregulated market conditions is to organize an ancillary services market. The growing share of distributed generation of variable (intermittent) energy sources and a change in the market position of consumers, causes the demand for distributed delivery of ancillary services. For this purpose, it is sought to use the ability of the regulatory measures:...
-
Discrete identification of continuous non-linear and non-stationary dynamical systems that is insensitive to noise correlation and measurement outliers
PublicationThe paper uses specific parameter estimation methods to identify the coefficients of continuous-time models represented by linear and non-linear ordinary differential equations. The necessary approximation of such systems in discrete time in the form of utility models is achieved by the use of properly tuned `integrating filters' of the FIR type. The resulting discrete-time descriptions retain the original continuous parameterization...
-
Dead time effects compensation strategy by third harmonic injection for a five-phase inverter
PublicationThis paper proposes a method for compensation of dead-time effects for a fivephase inverter. In the proposed method an additional control subsystem was added to the field-oriented control (FOC) scheme in the coordinate system mapped to the third harmonic. The additional control loop operates in the fixed, orthogonal reference frame ( α - β coordinates) without the need for additional Park transformations. The purpose of this method...
-
Multi-level models of transport systems for traffic management
PublicationThe region of Pomorskie uses a variety of tools for forecasting and analysing transport. They can be operated, calibrated and updated with data that will be collected and stored in the TRISTAR system. An initiative of the Department of Highway Engineering of the Gdansk University of Technology is designed to develop and implement an integrated and hierarchical system for forecasting and analysing transport called MST (Multilevel...
-
total number and biomass of bacteria in drinking water distribution systems.
PublicationIn the vast water supply network using traditional methods of treatment it is often impossible to maintain a constant and acceptable microbiological quality of water. In Poland the main reason of bacterial re-growth is presence of organic matter and nutrients in the circulating water and prolonged water retention in the network systems due to the decrease of water consumption, which has been observed for the last 20 years. In the...