Filters
total: 1873
filtered: 1511
displaying 1000 best results Help
Search results for: MEAN CYCLE WEIGHT
-
Hydraulic conductivity of a biopolymer treated sand
PublicationThis paper presents results of laboratory assessment of creating seepage barriers in a sandy soil using biopolymer additives (bio substance), which consist of polysaccharides and water. Polysaccharides strongly interact with water to produce a viscous suspension. The aim of the conducted work was to investigate the influence of a biosubstance employed in a highly permeable sandy soil. The amount of the biopolymer used in a sample...
-
Degradation of polycaprolactone modified with TPS or CaCO3 in biotic/abiotic seawater
PublicationThis paper is an investigation of the polymer degradation process in two types of seawater (with and without microorganisms) sourced from the Baltic Sea. The chosen polymeric materials were polycaprolactone modified with either thermoplastic starch (PCL/TPS>85%) or calcium carbonate (60% PCL/40% CaCO3) compared directly against unmodified polycaprolactone. All samples were incubated for 28 weeks in seawater with and without microorganisms...
-
The newly developed multipurpose ROV or an integrated mine hunting system
PublicationA modular mine hunting ROV concept is presented. The design is based on experience gained during 15 years of exploitation of the Ukwial ROV and development of Gluptak single shot mine hunting systems. The design goal was to multiply capabilities of the Ukwial without increasing weight and dimensional envelope. The vehicle is composed around powerful propulsion system that gives the system basic PVDS capability and mine disposal...
-
PLANOWANIE BEZPIECZNYCH I „ZIELONYCH” SYSTEMÓW KOMUNIKACYJNYCH
PublicationIn order to achieve balanced forms of urban infrastructure, which ensure comfort, safety and spatial order, when designing new solutions it is necessary to adopt a multi-facet approach which will combine everything that the local residents need but will respond harmoniously to the existing cultural landscape. It is therefore necessary to work out complex undertakings for the sake of planning and developing urban space. Coherent...
-
Cure kinetics of epoxy/MWCNTs nanocomposites: Isothermal calorimetric and rheological analyses
PublicationA combinatorial route has been applied in cure kinetics study of epoxy nanocomposites containing multi-walled carbon nanotubes (MWCNTs) based on differential scanning calorimetry and rheokinetic analyses under isothermal conditions. Pristine and amine-modified MWCNTs bearing primary and secondary amines were used at very low concentrations (0.1 and 0.3 wt.% based on epoxy weight). Model-free and model-fitting methods were applied...
-
Thermoplastic polyurethanes derived from petrochemical or renewable resources: A comprehensive review
PublicationThermoplastic polyurethanes (TPUs) materials are obtained by the reaction of polyol (ether-, ester-, and carbonate-based diols with average molecular weight in the range from 1,000 to 3,000 g/mol) with aliphatic or aromatic diisocyanates. Synthesized materials consist of the hard and soft segments which are separated in different level. All mechanical and thermal properties of TPUs depend on the chemical structure of used monomers,...
-
Structure-rheology relationship of fully bio-based linear polyester polyols for polyurethanes - Synthesis and investigation
PublicationThe synthesis of polyols from renewable substances as an alternative for petrochemical-based polyols play important matter in the polyurethane industry. In this work, the fully bio-based linear polyester polyols with different catalyst amounts were synthesized via two-step polycondensation method. The effect of various catalyst content on the structure and rheological behavior were established. Fourier Transform Infrared Spectroscopy,...
-
Synthesis and structure of Bi 5 FeTi 3 O 15 ceramics
PublicationAim of the present research was to fabricate and study crystal structure and phase composition of Bi5FeTi3O15 (BTFO) ceramics exhibiting Aurivillius - type structure. By means of simultaneous thermal analysis and X-ray diffraction analysis the process of synthesis of BTFO ceramics has been studied. Mixed oxide method followed by pressureless sintering was used for ceramics preparation. Three endothermic thermal effects have been...
-
Analysis of ring cracks in ceramic rolling elements using the boundary element method
PublicationCeramic materials have been increasingly used in bearing technology for over a dozen years. This is due to the characteristic properties of ceramic materials such as: high hardness, corrosion resistance, the possibility of use in aggressive chemical environments, as well as due to the lower specific weight compared to steel materials. However, the use of ceramic materials is connected with many limitations. The main disadvantages...
-
Prototype design and development of low-load-roof photovoltaic modules for applications in on-grid systems
PublicationFour prototypes of lightweight photovoltaic modules for applications in on-grid systems have been designed, developed, manufactured and tested for compliance with relevant IEC standards. Selected, commercially available materials characterized by thermogravimetry, differential scanning calorimetry, dilatometry, scanning electron microscopy and nanoindentation technique were used in frameless, adhesively-bonded sandwich-structures...
-
Chitin and derivative chitosan-based structures — Preparation strategies aided by deep eutectic solvents: A review
PublicationThe high molecular weight of chitin, as a biopolymer, challenges its extraction due to its insolubility in the solvents. Also, chitosan, as the N-deacetylated form of chitin, can be employed as a primary material for different industries. The low mechanical stability and poor plasticity of chitosan films, as a result of incompatible interaction between chitosan and the used solvent, have limited its industrialization. Deep eutectic...
-
Synchronous generator model taking into account the non-uniform saturation of the pole shoes
PublicationFor the evaluation of modern electric power systems with regard to their behavior, weight, and reliability a novel modeling and simulation tools have been developed. The paper presents circuit model of synchronous generator taking into account both the non-sinusoidal distribution of the stator and rotor winding, and non-uniform saturation of the pole shoes. This model is suitable for simulation of both salient and no-salient pole...
-
The Influence of the Co-Dopant Dexamethasone Phosphate on the Electrodeposition Process and Drug-Release Properties of Polypyrrole-Salicylate on Iron
PublicationIn this work, the influence of incorporation of two anti-inflammatory drugs dexamethasone phosphate and sodium salicylate on the electrodeposition process of polypyrrole (PPy) film on iron has been studied. The incorporation of the agents into PPy has been carried out in a one-step electropolymerization process on oxidizable iron. The role of each drug agent during the deposition process has been discussed. The morphological and...
-
Some geomechanical properties of a biopolymer treated medium sand
PublicationSome geomechanical properties of a biopolymer treated medium sand. This paper presents a laboratory assessment of geomechanical properties of sandy soil improved by biopolymer application. Additives (biosubstance) consist of polysaccharides and water. Biosubstance used in the project was xanthan gum, which comes from bacteria Xanthomonas campestris. Triaxial shear compression tests and unconfi ned compression tests were carried...
-
Application of linear buckling sensitivity analysis to economic design of cylindrical steel silos composed of corrugated sheets and columns
PublicationThe paper deals with global stability of steel cylindrical silos composed of corrugated walls and vertical columns with loads imposed by a bulk solid following Eurocode 1. The optimum silo design with respect to the steel weight was based on a sensitivity analysis method. The changes of silo column profiles at each design step were performed by means of influence lines for the buckling load factor due to the unit column bending...
-
AN ENERGY APPROACH TO THE FATIGUE LIFE OF SHIP PROPULSION SYSTEMS
PublicationThe conducted research investigations aimed to carry out an identification of the constructional materials fatigue state of the ship propulsions’ rotational mechanical units for diagnostic purposes. The fatigue cracks of the elements transmitting mechanical energy streams from the propulsion engines to the ship propellers or to the generators of the ship’s electric power station stand for a primary reason for the secondary, usually...
-
Novel therapeutic compound acridine–retrotuftsin action on biological forms of melanoma and neuroblastoma
PublicationPURPOSE: As a continuation of our search for anticancer agents, we have synthesized a new acridine-retrotuftsin analog HClx9-[Arg(NO2)-Pro-Lys-Thr-OCH3]-1-nitroacridine (named ART) and have evaluated its activity against melanoma and neuroblastoma lines. Both tumors develop from cells (melanocytes, neurons) of neuroectodermal origin, and both are tumors with high heterogeneity and unsatisfactory susceptibility to chemotherapies....
-
Multi-instrument analysis of L-band amplitude scintillation observed over the Eastern Arabian Peninsula
PublicationThe study of scintillation-causing ionospheric irregularities is important to mitigate their effects on satellite communications. It is also important due to the spatial and temporal variability of these irregularities, given that their characteristics differ from one region to another. This study investigates the spatial and temporal characteristics of L1 amplitude scintillation-causing ionospheric irregularities over the Eastern...
-
Weryfikacja Poziomów Nienaruszalności Bezpieczeństwa z uwzględnieniem Zagadnień Ochrony Informacji
PublicationNiniejszy rozdział poświęcono wybranym istotnym zagadnieniom analizy bezpieczeństwa funkcjonalnego, w szczególności weryfikacji poziomów nienaruszalności bezpieczeństwa SIL funkcji bezpieczeństwa implementowanych w rozproszonych systemach sterowania i zabezpieczeń z uwzględnieniem zagadnień ochrony informacji. Zaproponowano metodę opartą na informacji ilościowej i jakościowej do weryfikacji SIL (IEC 61508, 61511) z uwzględnieniem...
-
Władza misjonarzy. Zmierzch i świt świeckiej religii w Dolinie Krzemowej
Publication"Władza misjonarzy" to książka o misjonarskim zapale zmieniania świata i o kryzysie świeckiej religii towarzyszącej liderom nowych technologii, o ich świętokradztwach i sprofesjonalizowanej pokucie mającej przywrócić harmonię technologicznego raju na ziemi z Alphabetem, Metą, Apple i TikTokiem w roli głównej. Także o skruszonych inżynierach, żałujących każdej chwili, którą poświęcili na wymyślanie uzależniających algorytmicznych rozwiązań...
-
Acoustic Processor of the MCM Sonar
PublicationThis paper presents the concept of an acoustic processor of the mine countermeasure sonar. Developed at the Department of Marine Electronics Systems, Gdansk University of Technology, the acoustic processor is an element of the MG-89, a modernised underwater acoustic station. The focus of the article is on the modules of the processor. They are responsible for sampling analogue signals and implementing the algorithms controlling...
-
Types of wear and tear of biomaterials used in orthopaedic surgery
PublicationPurpose of this paper is presentation of observations on different kinds of wear and tear of biomaterials used in contemporary orthopaedic surgery. Types of prosthesis damage, encountered in medical practice, and their causes have been described. Results of many clinical studies were analysed to review prosthesis damage from the stage of implanting (such as intrusion of a foreign object between its components) to their natural...
-
Towards systemic functional safety and security management in hazardous plants
PublicationThe aim of this article is to identify and discuss some issues related to functional safety and security management in hazardous industrial plants. The safety functions are to be realised using the electric / electronic / programmable electronic systems (E/E/PESs) or the safety instrumented systems (SISs) that are designed and operated respectively according to IEC 61508 and IEC 61511 requirements in life cycle. Although the role...
-
Contaminants in airport runoff water
PublicationDespite the many positives ensuing from the rapid expansion of the air transport sector, airport operations as a whole are a substantial source of environmental pollution.Increases in aviation developments have serious consequences on the surrounding air, soil and water bodies like lakes, rivers and ground water. The present work deals with the determination of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls...
-
Problems in designing and operating the functional safety solutions of higher integriity levels
PublicationThe aim of this article is to identify and discuss some problems that have been encountered in designing and operating the functional safety solutions of higher safety integrity levels (SIL 3 and SIL 4) in the light of analyses outlined in a new version of the international standard IEC 61508:2010. Examples of such solutions are the electric / electronic / programmable electronic systems (E/E/PESs) and the safety instrumented systems...
-
Comparative testing of numerical models of river ice jams
PublicationIce processes in general, and ice jams in particular, play a dominant role in the hydrologic regime of Canadian rivers, often causing extreme floods and affecting the life cycle of many aquatic, terrestrial, and avian species. Various numerical models have been developed to help simulate the formation and consequences of these very dynamic and often destructive jam events. To test and compare the performance of existing models,...
-
Integration of natural and artificial intelligence in production systems
PublicationIntegration processes play an increasingly important role in modern economy, and seriously co-decide about the effectiveness of the company. Integration phase occurs in the system life cycle by preceding the final stages of its implementation and activation. In turn, used in software engineering (SE) iteration-evolutionary models, such as spiral model make that the integration activities can occur in varying degrees in all phases...
-
Analiza porównawcza kosztów środowiskowych budowy i eksploatacji drogi ekspresowej w technologii asfaltowej i betonowej, CZĘŚĆ 1
PublicationW artykule przedstawiono opis analizy porównawczej kosztów środowiskowych budowy i eksploatacji drogi ekspresowej w technologii asfaltowej i betonowej. Do przeprowadzenia badania wykorzystano analizę LCA (ang. Life Cycle Assessment). Jako założenia przyjęto warianty konstrukcji nawierzchni opracowane dla planowanej drogi ekspresowej S6 na odcinku Lębork (wraz z obwodnicą Lęborka) –obwodnica Trójmiasta, a także trzy scenariusze...
-
Application analysis of a hybrid solid oxide fuel cell-gas turbine system for marine power plants
PublicationThe results of theoretical studies of the possibilities of using hybrid solid oxide fuel cell–gas turbine (SOFC-GT) systems for marine power plants are presented. A 500 kW auxiliary marine power plant scheme using stacks of SOFCs in combination with a regenerative gas turbine operating with over-expansion based on our recent patent application is proposed. The results of mathematical modelling showed the opportunity to obtain a...
-
Comparative study of a combined heat and power plant retrofitted by CO2 capture during the combustion of syngas from sewage sludge gasification versus zero-emission combustion of hydrogen produced using renewables
PublicationWith ecological requirements aimed at limiting the production of CO2, it is necessary to produce all, or most of the energy from RES. During the transformation process, ecological and highly efficient combustion power plants will be needed. The classic cycle of combined heat and power (CCGT) with green improvements will continue to be one of the most suitable technologies for this task. This article presents the modernization of...
-
The effect of elevated temperature on LCF damage growth in 2024AA – Experiment and modeling
PublicationThis paper presents the results of experimental low-cycle fatigue (LCF) tests conducted on EN-AW 2024 alloy in T3511 temper at 100 ◦C, 200 ◦C and 300 ◦C. The material’s basic fatigue characteristics were determined, such as fatigue life curve and cyclic strain curve. Both the hysteresis loop and nature of fracture surfaces obtained in macro- and microscopic observations (scanning electron microscope, SEM) were accounted for. The...
-
Experimental investigations and damage growth modeling of EN‐AW 2024 aluminum alloy under LCF loading accounting creep pre‐deformation
PublicationThis article presents the results of experimental tests of creep rupture and of low-cycle fatigue (LCF) of EN-AW 2024 aluminum alloy devoid of damage and having preliminary damage. The preliminary damage was dealt in the process of creep at elevated temperature 100C, 200C, and 300C until achievement of two different strain values at each temperature. Samples with preliminary damage were subjected to fatigue tests at room temperature....
-
Support Product Development Framework by Means of Set of Experience Knowledge Structure (SOEKS) and Decisional DNA
PublicationIn this paper, we propose a framework to support product development activi-ties by utilizing Set of Experience Knowledge Structure (SOEKS) and Decisional DNA (DDNA). This idea will provide a new direction to researchers working on product development, especially designers and manufacturers. They will be working on the same platform and this will be reducing their communication gap. Once the final idea is perceived about product...
-
Analiza siłowni nadkrytycznych oraz ultranadkrytycznych
PublicationNiniejszy artykuł zawiera przegląd istniejących rozwiązań siłowni nadkrytycznych oraz ultra nadkrytycznych. Przedstawiono historię rozwoju bloków na parametry nadkrytyczne. Obecny stan technologii został zaprezentowany – są to następujące parametry pary świeżej: 650°C oraz 330 bar. W Polsce istnieje 8 bloków pracujących na parametry nadkrytyczne. Ich parametry pracy zostały przedstawione w tekście. Z kolei elektrownią parową posiadającą...
-
Application of the F-statistic of the Fisher-Snedecor distribution to analyze the significance of the effect of changes in the compression ratio of a diesel engine on the value of the specific enthalpy of the exhaust gas flow
PublicationThe paper discusses the impact of changes in the compression ratio on the operating parameters of a diesel engine, e.g. on the temperature of exhaust gases. It presents the construction of the laboratory test stand, on which experimental measurements were realized. It is characterized how the actual changes of the compression ratio were introduced to the existing engine. The program of experimental investigations taking into account...
-
Thermochemical Conversion of Biomass and Municipal Waste into Useful Energy Using Advanced HiTAG/HiTSG Technology
PublicationAn advanced thermal conversion system involving high-temperature gasification of biomass and municipal waste into biofuel, syngas or hydrogen-rich gas is presented in this paper. The decomposition of solid biomass and wastes by gasification is carried out experimentally with a modern and innovative regenerator and updraft continuous gasifier, among others. A ceramic high-cycle regenerator provides extra energy for the thermal conversion...
-
Effect of operating conditions on N 2 O production in an anammox sequencing batch reactor containing granular sludge
PublicationNitrous oxide (N2O) is one of the gases with the greatest impact in the atmosphere due to its persistence and significant contribution to the greenhouse effect. This study provides an insight into the dynamics of N2O production in wastewater nitrogen removal systems. A 10 L sequencing batch reactor containing enriched anammox biomass was subjected to different operational conditions, i.e., temperature, feed time, NO2 /NH4 þ ratio...
-
Review of the Complexity of Managing Big Data of the Internet of Things
PublicationTere is a growing awareness that the complexity of managing Big Data is one of the main challenges in the developing feld of the Internet of Tings (IoT). Complexity arises from several aspects of the Big Data life cycle, such as gathering data, storing them onto cloud servers, cleaning and integrating the data, a process involving the last advances in ontologies, such as Extensible Markup Language (XML) and Resource Description...
-
Safety Integrity Verification Issues of the Control Systems for Industrial Process Plants
PublicationThe aim of this article is to identify and discuss some issues that can be encountered in designing the industrial automation and control systems (IACS) for implementing safety functions. In a functional safety standard IEC 61511 for the process industry such systems are named the basic process control systems (BPCS) and the safety instrumented systems (SIS). In a generic functional safety standard IEC 61508 they are depicted as...
-
Przegląd systemów ładowania elektrycznych osobowych pojazdów i koncepcja dwukierunkowej ładowarki pokładowej
PublicationAktualnie trwa intensywny rozwój pojazdów elektrycznych (EV) i hybrydowych typu plug-in (PHEV) z pokładowymi bateriami akumulatorów. Badania w tej dziedzinie skupiają się na maksymalizowaniu sprawności oraz minimalizowaniu masy i objętości systemów ładowania baterii. W artykule przedstawiono podział systemów ładowania osobowych pojazdów typu EV/PHEV. Opisano systemy ładowania przewodowego z podziałem na ładowarki pokładowe i zewnętrzne, systemy...
-
Od postawy prozdrowotnej w stoczni jachtowej do ograniczania zagrożeń na stanowisku pracy formierza-laminiarza
PublicationTematyka zdrowia i bezpieczeństwa pracowników, coraz częściej popularyzowana w świecie biznesu, nadal stanowi dość mało rozpoznany obszar działalności polskich przedsiębiorstw. Niniejszy artykuł porusza ważką kwestię promocji zdrowia w miejscu pracy jako czynnika zwiększającego efektywność pracy oraz jego wpływ na osiąganie wysokiej jakości produktu. Publikacja omawia znaczenie postawy prozdrowotnej i sposobów jej kształtowania...
-
Rotor Blade Geometry Optimisation in Kaplan Turbine
PublicationThe paper presents the description of method and results of rotor blade shape optimisation. The rotor blading constitutes a part ofturbine flow path. Optimisation consists in selection of the shape that minimises ratio of polytrophic loss. Shape of the blade isdefined by the mean camber line and thickness of the airfoil. Thickness is distributed around the camber line based on the ratio ofdistribution. Global optimisation was done...
-
POSSIBILITY OF IDENTIFICATION OF TECHNICAL CONDITION OF BEARINGS FOR SELF-IGNITION ENGINES BY APPLICATION OF ACOUSTIC EMISSION AS A DIAGNOSTIC SIGNAL
PublicationThis paper presents the results of empirical studies where the acoustic emission (AE) method was applied to identify the technical condition of sliding surfaces of main and crank bearings for main diesel engines. The test results indicate that the measurements of the AE parameters allow the technical condition identification for bearings of this type. The results refer to the measurements of the parameters for AE generated in the...
-
Application of magnetic nanoparticles for magnetic solid-phase extraction in preparing biological, environmental and food samples
PublicationThe need to obtain meaningful results as the basis for determining the content of trace amounts of analytes has become the driving force behind the development of modern analytical techniques, including sample-preparation techniques, such as solid-phase extraction (SPE). Recently, great interest was aroused in the use of magnetic nanoparticles (MNPs) in SPE. These materials exhibit high selectivity, and, in small amounts, can provide...
-
Plate heat exchanger with porous structure for potential use in ORC system
PublicationThe experimental analysis of passive heat transfer intensification in the case of plate heat exchanger has been carried out. The passive intensification was obtained by a modification of the heat transfer surface, which was covered by a metallic porous microlayer. The experiment was accomplished in two stages. In the first stage the commercial stainless steel gasketed plate heat exchanger was investigated, while in the second one...
-
Plate heat exchanger with porous structure for potential use in ORC system
PublicationThe experimental analysis of passive heat transfer intensification in the case of plate heat exchanger has been carried out. The passive intensification was obtained by a modification of the heat transfer surface, which was covered by a metallic porous microlayer. The experiment was accomplished in two stages. In the first stage the commercial stainless steel gasketed plate heat exchanger was investigated, while in the second one...
-
Influence of metallic porous microlayer on pressure drop and heat transfer of stainless steel plate heat exchanger
PublicationThe experimental analysis of passive heat transfer intensification in the case of plate heat exchanger has been carried out. On the heat transfer surface of heat exchanger the metallic porous layer was created. The experiment was accomplished in two stages. In the first stage the commercial stainless steel gasketed plate heat exchanger was investigated, while in the second one – the identical heat exchanger but with the modified...
-
EVALUATION OF THE SEMIVARIOGRAM SELECTION ON THE KRIGING INTERPOLATION
PublicationThe aim of the paper is to present the possibilities of geostatistical interpolation kriging method using in the process of generating digital terrain models (DTM). The source of data is a direct measurements realized with a precision GNSS positioning kinematic measurement technique RTN. Kriging algorithm was analysed, especially in the meaning of a semivariogram every step. Theoretical semivariogram selection influence on the...
-
THEORETICAL POTENTIAL OF HYDROGEN PRODUCTION FROM TEXTILES WASTES IN POMERANIAN REGION BY MEANS OF DARK FERMENTATION
PublicationModel has been developed for calculating theoretical mass of hydrogen produced from textile wastes by mean of dark fermentation. As vegetable fibres wastes were chosen two mostly used — cotton and linen (flax). As the synthethic carbohydrate rich fiber was chosen viscose. In the background there were introduced: problems of dark fermentation, characteristics of textile material structure. Additionally pathways of the process...
-
The Examination of the Upper Layers of the Seabed by the Means of the Acoustic Methods
PublicationPropagation of acoustic waves in the sea, in particular in shallow sea, depends on several factors. The basic of them are source power and frequency of acoustic waves, spatial distribution inhomogeneous medium in which acoustic wave propagates, and distributions of speed of sound and density of seawater. The coastal conditions, which limit water medium from above (free surface of the sea) and from bottom (the seabed), are no less...