Filters
total: 4561
-
Catalog
- Publications 3819 available results
- Journals 68 available results
- Conferences 21 available results
- Publishing Houses 1 available results
- People 75 available results
- Projects 2 available results
- e-Learning Courses 34 available results
- Events 6 available results
- Open Research Data 535 available results
displaying 1000 best results Help
Search results for: RINGING FREQUENCY
-
Immobilization of thermostable beta glucosidase from Sulfolobus shibatae by cross-linking with transglutaminase
PublicationOpracowano metodę immobilizacji termostabilnej beta-glukozydazy przez katalizowane transglutaminazą sieciowanie na nośniku krzemionkowym. Aktywność uzyskanego preparatu wynosi 3883 U/g nośnika. Największą wydajność unieruchamiania uzyskano w temperaturze 50C, przy pH 5,0. Immobilizacja prawie nie zmieniała optymalnego pH działania enzymu, który uzyskiwał największą aktywność w temperaturze 98C. Badania w reaktorze kolumnowym wykazały...
-
Molecular insights into receptor binding energetics and neutralization of SARS-CoV-2 variants
Publication -
Effects of whole-body vibration warm-up on subsequent jumping and running performance
Publication -
Accuracy of CAD/CAM and 3D printing in the treatment of feline femoral neck fracture
Publication -
Assessment of Adjustment of GNSS Railway Measurements with Parameter-Binding Conditions in a Stationary Scenario
Publication -
NK1 receptor binding of a few low molecular weight 3,5-bistrifluoromethylbenzene derivatives
Publication -
Fentanyl Family at the Mu-Opioid Receptor: Uniform Assessment of Binding and Computational Analysis
Publication -
Vertical vibration reduction and audible sound analysis in surface grinding with electroplated tools
PublicationOne of the first approaches to the development of a grinding process monitoring system based on audible sound sensors is presented in the paper. Electroplated diamond tools (abrasive D64 and D107) were used in a modified single-disc lapping machine configuration for flat grinding of ceramics (Al2O3). The main aim of the machine modification was to reduce the vertical vibration in order to decrease the tool wear and to increase...
-
Cross-linking of epoxy-oligomeric mixtures in the presence of modified phenol-formaldehyde resins
PublicationCross-linking of epoxy oligomeric mixtures consisting of industrial epoxy resin ED-20, oligoetheracrylate TGM-3, peroxide derivative of epoxy resin ED-24 and phenol-formaldehyde oligomer with unsaturated methacrylate fragments or peroxide groups was studied in the presence of polyethylenepolyamine at room temperature and heated to 383, 403 or 423 K for 15, 30, 45, 60 and 75 minute. The influence of mixture composition, temperature...
-
Green engineered biomaterials for bone repair and regeneration: Printing technologies and fracture analysis
PublicationDespite the exceptional self-regeneration properties of bone, severe injuries often require additional surgical intervention such as using artificial bone constructs. These structures need to meet a number of criteria regarding their structure, performance, alongside the rate and the mechanism of erosion and fracture when implanted, for stimulating the regeneration of defected bone and, more critically providing support in the...
-
Viscoplastic properties of coated textile material ''Panama'' and its usage for hanging roofs.
PublicationPodano sposób identyfikacji parametrów materiałowych lepkoplastycznego prawa Bodnera-Partoma i prawa Chaboche´a. Przedstawiono model sieci gęstej pozwalający na zastosowanie wyników prób jednoosiowego rozciągania do rzeczywistej tkaniny. Pokazano zastosowanie wyników w analizie statycznej i dynamicznej przekrycia wiszącego typu hypar poddanego wstępnemu naprężaniu. Przeanalizowano zmianę geometrii i częstości drgań własnych.
-
The effect of chlorinated drinking water consumption on levels of volatile organohalogen compounds in urine.
PublicationW przedstawionej pracy podjęto próbę oznaczenia niezmienionych form lotnych rozpuszczalników chlorowcoorganicznych w próbkach materiału biologicznego jakim jest mocz dawców, używających w gospodarstwie domowym a także w pracy wody uzdatnianej między innymi w procesie chlorowania. Do wykonania oznaczeń zastosowano zmodyfikowaną technikę analizy fazy nadpowierzchniowej nad cienką warstwą cieczy z samoczynną generacją ciekłego sorbentu...
-
Single-stranded DNA-binding proteins (SSBs) - sources and applicationsin molecular biology
PublicationBiałka wiążące się do jednoniciowego DNA (SSB) odgrywają ważną rolę w replikacji, rekombinacji i naprawie DNA u bakterii, archea i eukariota. Ostatnio wzrosło zainteresowanie białkami SSB jako przydatnymi narzędziami w metodach badawczych biologii molekularnej, analitycznych i diagnostycznych. Większość znanych prokariotycznych białek SSB zbudowanych jest z czterech podjednostek (homotetramer) z jedną domeną wiążąca (OB) jednoniciowe...
-
Arkadiusz Lewicki dr hab. inż.
People -
Marek Krawczuk prof. dr hab. inż.
PeopleScientific background 1987 - graduated Gdansk Univeristy of Technology, Faculty of Machine Design 1991 - PhD - Institute of Fluid Flow Machinery Gdansk 1995 - DSc - Institute of Fluid Flow Machinery Gdansk 2003 - Prof. - Institute of Fluid Flow Machinery Gdansk Profesional bakground 1987-1989 Gdansk University of Technology 1989 -2007 Institute of Fluid Flow Machinery Gdansk 2001-2003 Univeristy of Warmia and Mazury Olsztyn 2003...
-
The statistic properties of rms voltage and frequency in the ship's electrical power system
Open Research DataThe dataset is a part of the research results on the quality of supply voltage on bus bars of the main switchboard of the ship's electrical power system in different states of ship exploitation. The attached dataset contains the results of a statistical analysis of rms voltage and frequency in the ship's electrical power system. The following statistical...
-
Simulation of the weight averaging of pulse frequency modulated sensor output signal
Open Research DataThe aim of the research is investigation of the efficiency of weight averaging of pulse frequency modulated signal. It was shown that from the point of view of the reduction of the sampling error the best are polynomial weighing functions, for which the maximum of this component error decreases proportionally to the appropriate power of the number of...
-
Mobile operators at war: opinion mining and sentiment analysis on social media
PublicationConsidering hermetic and very competitive market such as mobile operator ones, social media has become best alternative for contact with customer and gathering data and opinions. Different style of running social media profiles is giving different results. The research presented in this paper aims to show the number of responses gathered from polish Internet users and its sentiment for mobile operator brands. It also presents practical...
-
The Impact of Lexicon Adaptation on the Emotion Mining From Software Engineering Artifacts
PublicationSentiment analysis and emotion mining techniques are increasingly being used in the field of software engineering. However, the experiments conducted so far have not yielded high accuracy results. Researchers indicate a lack of adaptation of the methods of emotion mining to the specific context of the domain as the main cause of this situation. The article describes research aimed at examining whether the adaptation of the lexicon...
-
Text Mining Algorithms for Extracting Brand Knowledge; The fashion Industry Case
PublicationBrand knowledge is determined by customer knowledge. The opportunity to develop brands based on customer knowledge management has never been greater. Social media as a set of leading communication platforms enable peer to peer interplays between customers and brands. A large stream of such interactions is a great source of information which, when thoroughly analyzed, can become a source of innovation and lead to competitive advantage....
-
MANAGEMENT OF THE POST-MINING AREAS IN DEVELOPMENT POLICY OF ZIELONA GORA (POLAND)
Publication -
Response of a steel tank during earthquakes and mining tremors - experimental investigation
PublicationCylindrical steel tanks are very popular shell structures used to store the products of chemical and petroleum industries. Any failure might have disastrous consequences, therefore their safety and reliability is essential. Earthquakes are the most dangerous and also the most unpredictable dynamic loads acting on such structures. On the other hand, mining tremors are usually considered to be less severe due to lower acceleration...
-
Water Reservoirs as an Element of Shaping Water Resources of Post-Mining Areas
Publication -
Flow field around growing and rising vapour bubble by PIV measurement.
PublicationPrzedstawiono wyniki badania pól prędkości wokół wzrastających i unoszących się pęcherzyków parowych generowanych z pojedynczego centrum nukleacji. W badaniach zastosowano komercyjny układ Particle Image Velocimetry.
-
Resonator-Loaded Waveguide Notch Filters with Broad Tuning Range and Additive-Manufacturing-Based Operating Frequency Adjustment Procedure
PublicationThis article presents a new class of ring-resonator-loaded waveguide notch filters with a broad tuning range, low cost, and improved performance. The proposed approach employs a comple-mentary asymmetric split ring resonator coupled to a microstrip transmission line and excited in a rectangular waveguide. An equivalent circuit model is proposed to explain the working principle of the proposed notch filter. The adjustment of the...
-
Prediction of Ship Resonant Rolling - Related Dangerous Zones with Regard to the Equivalent Metacentric Height Governing Natural Frequency of Roll
PublicationPotentially dangerous zones corresponding to dynamical stability phenomena, possibly encountered by ships sailing in rough sea, are estimated nowadays with the use of the method recommended by IMO in the guidance coded MSC.1/Circ.1228. In this IMO method the parameter governing the natural period of roll is the initial metacentric height. Some earlier studies revealed that the initial metacentric height...
-
Dispersive Delay Structures With Asymmetric Arbitrary Group-Delay Response Using Coupled-Resonator Networks With Frequency-Variant Couplings
PublicationThis article reports the design of coupled-resonatorbased microwave dispersive delay structures (DDSs) with arbitrary asymmetric-type group delay response. The design process exploits a coupling matrix representation of the DDS circuit as a network of resonators with frequency-variant couplings (FVCs). The group delay response is shaped using complex transmission zeros (TZs) created by dispersive cross-couplings. We also present an...
-
Inline Microstrip Bandpass Filter With Two Transmission Zeros and Increased Order Using Spurious Resonance of Frequency-Dependent Inverter
PublicationA design method for a class of fourth-order inline microstrip bandpass filter with two transmission zeros and 20% fractional bandwidth is presented. The filter consists of two quarter-wavelength transmission-line resonators coupled by a frequency-dependent inverter. The inverter is composed of two open-ended stubs that are connected by an interdigital capacitor and introduces two poles and two transmission zeros in the filter response....
-
Lagrangian model of an isolated dc-dc converter with a 3-phase medium frequency transformer accounting magnetic cross saturation
PublicationThis article presents a nonlinear equivalent circuit model of an isolated dc-dc converter with a 3-phase medium frequency transformer. The model takes into account the magnetic cross saturation of the 3-phase core-type magnetic circuit. The model is suitable in detailed electromagnetic transient simulations of power systems involving isolated dc-dc converters. The model is developed using the Lagrange energy method. It involves...
-
Recent Advances in Accelerated Multi-Objective Design of High-Frequency Structures using Knowledge-Based Constrained Modeling Approach
PublicationDesign automation, including reliable optimization of engineering systems, is of paramount importance for both academia and industry. This includes the design of high-frequency structures (antennas, microwave circuits, integrated photonic components), where the appropriate adjustment of geometry and material parameters is crucial to meet stringent performance requirements dictated by practical applications. Realistic design has...
-
The Influence of a Photovoltaic Micro-Installation on the Low-Frequency Parameters of Electricity at PCC and Its Impact on the Thermal Characteristics of Selected Devices
PublicationThis manuscript illustrates the measurement results of parameters describing the quality of energy at the PCC (point of common coupling) of a photovoltaic micro-installation that can significantly affect devices in the same power grid. The analyses reflecting heating of selected devices used in domestic installations, which were performed in an isolated laboratory environment, are also indicated. The conducted study aimed at checking...
-
Laboratory Load Model Based on 150 kVA Power Frequency Converter and Simulink Real-Time – Concept, mplementation, Experiments
PublicationFirst section of the paper provides technical specification of laboratory load model basing on 150 kVA power frequency converter and Simulink Real-Time platform. Assumptions, as well as control algorithm structure is presented. Theoretical considerations based on criteria which load types may be simulated using discussed laboratory setup, are described. As described model contains transformer with thyristor-controlled tap changer,...
-
Analysis of Positioning Error and Its Impact on High Frequency Performance Parameters of Differential Signal Coupler of Differential Signal Coupler
PublicationThis paper presents the analysis of the effect of differential signal coupler positioning accuracy on its high frequency performance parameters for contact-less high speed chip-to-chip data transmission on PCB application. Our considerations are continuation of the previous works on differential signal coupler concept, design methodology and analysis for high speed data transmission monitoring presented in [1, 2]. The theoretical...
-
Comparative analysis of zinc status, food products' frequency intake and food habits of 11-year-old healthy children
Publication -
The Unsteady Low-Frequency Forces Acting on the Rotor Blade in the First Stage on an Axial Compressor of SO-3 Jet Engine
Publication -
The current amplifier in low frequency noise measurements; Absolute calibration and rigorous 1/f noise extraction for MOSFET´s
PublicationPrzedstawiono budowę wzmacniacza prądowego i sposób obliczania szumów wyjściowych przy dołączonym do wejścia rezystorze wzorcowym. Przedstawiono wyniki eksperymentów potwierdzających prawidłowość przyjętego sposobu postępowania. Zaproponowano metodę wyznaczania składowej 1/f szumów drenu tranzystora MOSFET.
-
Broadband Modeling of Motor Cable Impact on Common Mode Currents in VFD
PublicationExamination of conducted EMI generation and propagation in AC motor drives fed by frequency converter requires to consider parasitic capacitances in converters, motor windings and feeding cables to be taken into account. AC motor winding voltage transients and related common mode currents are significantly correlated with resonance effects occurring in converter's load circuits. Intensity levels of these phenomena depend...
-
Mining of Mineral Deposits
Journals -
Stanisław Maciej Kot prof. dr hab.
People -
Jacek Tejchman prof. dr hab. inż.
People -
Performance and emission characteristics of diesel engines running on gaseous fuels in dual-fuel mode
PublicationConventional fossil fuels are being substituted with alternative green fuels because of their greenhouse gas emissions and pollution problems, which pose a severe threat to the environment. Several studies have reported the usage of biodiesel and gaseous fuels in both single and dual-fuel modes. Gaseous fuels such as producer gas, biogas, syngas, and hydrogen produced from renewable biomass could potentially be used along with...
-
Enzymatic and Chemical Cross-Linking of Bacterial Cellulose/Fish Collagen Composites—A Comparative Study
PublicationThis article compares the properties of bacterial cellulose/fish collagen composites (BC/Col) after enzymatic and chemical cross-linking. In our methodology, two transglutaminases are used for enzymatic cross-linking—one recommended for the meat and the other proposed for the fish industry—and pre-oxidated BC (oxBC) is used for chemical cross-linking. The structure of the obtained composites is characterized by scanning electron...
-
Enhancing the Effectiveness of the Diamond Metal Bond Instrument when Grinding High-Strength Materials
Publication -
Application of the Optimization Methods to the Search of Marine Propulsion Shafting Global Equilibrium in Running Condition
PublicationFull film hydrodynamic lubrication of marine propulsion shafting journal bearings in running condition is discussed. Considerable computational difficulties in non-linear determining the quasi-static equilibrium of the shafting are highlighted. The approach using two optimization methods (the particle swarm method and the interior point method) in combination with the specially developed relaxation technique is proposed to overcome...
-
Accelerated design optimization of miniaturized microwave passives by design reusing and Kriging interpolation surrogates
PublicationElectromagnetic (EM) analysis has become ubiquitous in the design of microwave components and systems. One of the reasons is the increasing topological complexity of the circuits. Their reliable evaluation—at least at the design closure stage—can no longer be carried out using analytical or equivalent network representations. This is especially pertinent to miniaturized structures, where considerable EM cross-coupling effects occurring...
-
Medical-Grade PCL Based Polyurethane System for FDM 3D Printing—Characterization and Fabrication
PublicationThe widespread use of three-dimensional (3D) printing technologies in medicine has contributed to the increased demand for 3D printing materials. In addition, new printing materials that are appearing in the industry do not provide a detailed material characterization. In this paper, we present the synthesis and characterization of polycaprolactone (PCL) based medical-grade thermoplastic polyurethanes, which are suitable for forming...
-
Analysis of turnouts with non-linear curvature of diverging track for different train running speeds
PublicationThe paper deals with the issue of shaping a variable curvature in the diverging track of the railway turnout. Solution without a circular arc in the central zone, comprising two zones of non-linear curvature, of the same length, having zero curvature values at the end points, was adopted as a model, on the basis of the previously conducted dynamic tests. Optimum type of curvature was selected from the point of view of the kinematic...
-
Modifiers for Medical Grade Polymeric Systems used in FDM 3D Printing - Short Review
PublicationFDM 3D printing could find an application in the wide range of biomedical applications. Unfortunately, the quantity of polymeric biomaterials suitable to processing into filaments is limited. The most frequently used biomaterials for medical constructs such as bone grafts, soft tissue scaffolds or another DDS include PCL, PLA, PVA, HPC, EVA copolymer, EC and TPUs. Various modifiers such as TCP, HA, TEC, MMC could be applicated...
-
Reduced-cost surrogate modelling of compact microwave components by two-level kriging interpolation
PublicationFull-wave electromagnetic (EM) analysis is a versatile tool for evaluating the performance of high-frequency components. Its potential drawback is its high computational cost, inhibiting the execution of EM-driven tasks requiring massive simulations. The applicability of equivalent network models is limited owing to the topological complexity of compact microstrip components because of EM cross-coupling effects. Development of...
-
Rapid Multi-band Patch Antenna Yield Estimation Using Polynomial Chaos-Kriging
PublicationYield estimation of antenna systems is important to check their robustness with respect to the uncertain sources. Since the Monte Carlo sampling-based real physics simulation model evaluations are computationally intensive, this work proposes the polynomial chaos-Kriging (PC-Kriging) metamodeling technique for fast yield estimation. PC-Kriging integrates the polynomial chaos expansion (PCE) as the trend function of Kriging metamodel...