Filters
total: 1358
filtered: 1191
displaying 1000 best results Help
Search results for: THE COMPRESIVE STRENGTH
-
Sensitivity analysis of a composite footbridge
PublicationThis work include an example of sensitivity analysis for the design of a composite footbridge. A sandwich structure is used, consisting two high-strength skins separated by a core material. The analysis was conducted for two numerical models. The first one is a simple, single-span beam of a composite cross-section (laminate and foam), with different Young’s modulus for each material. Calculations were made by means of a MATLAB-based...
-
EVALUATION OF SOUND QUALITY FEATURES ON ENVIRONMENTAL NOISE EFFECTS – A CASE STUDY APPLIED TO ROAD TRAFFIC NOISE
PublicationThe paper shows a study on the relationship between noise measures and sound quality (SQ) features that are related to annoyance caused by the traffic noise. First, a methodology to perform analyses related to the traffic noise annoyance is described including references to parameters of the assessment of road noise sources. Next, the measurement setup, location and results are presented along with the derived sound quality features....
-
BADANIA POMIAROWE I ANALIZA PRZYDATNOŚCI METODY RSS DLA POTRZEB RADIOLOKALIZOWANIA
PublicationReferat dotyczy lokalizowania obiektów w sieciach radiokomunikacyjnych, pracujących w specyficznym środowisku propagacji fal radiowych, jakim jest terminal kontenerowy. Opisano podstawy teoretyczne metody RSS (Received Signal Strength), w której szacuje się odległości pomiędzy stacjami referencyjnymi a lokalizowanym obiektem na podstawie znajomości modelu propagacyjnego opisującego tłumienie fali radiowej. Przedstawiono metodykę...
-
3D Printing of Metallic Implants
PublicationThe fabrication of various elements, solid and open porous structures of stainless steel and Ti alloy is described. The process was started with the design of 3D models in CAD/CAM system. The 3D models were transformed into *.stl files and then the manufacturing process of the real structures by means of the selective laser melting with the SLM Realizer 100 3D printer was made. The paper shows the porous specimens made for possible...
-
Analysis of the cyclic load-unload-reload tests of VALMEX aged fabric
PublicationThe paper presents mechanical response of the VALMEX fabric during the cyclic loading-unloading and re-loading experiments. Two types of the aged material used for nearly 20 years as the roofing of the Forest Opera in Sopot (Poland) have been tested. The results have been separately obtained for the warp and fill di-rections. The comparative analysis has revealed that the material aged in service is more durable in the fill di-rection,...
-
Bacterial nanocellulose as a microbiological derived nanomaterial
PublicationBacterial nanocellulose (BNC) is a nanofibrilar polymer produced by strains such as Gluconacetobacter xylinus, one of the best bacterial species which given the highest efficiency in cellulose production. Bacterial cellulose is a biomaterial having unique properties such as: chemical purity, good mechanical strength, high flexibility, high absorbency, possibility of forming any shape and size and many others. Such a large number...
-
ESTIMATION OF YOUNG`S MODULUS OF THE POROUS TITANIUM ALLOY WITH THE USE OF FEM PACKAGE
PublicationPorous structures made of metal or biopolymers with a structure similar in shape and mechanical properties to human bone can easily be produced by stereolithographic techniques, e.g. selective laser melting (SLM). Numerical methods, like Finite Element Method (FEM) have great potential in testing new scaffold designs, according to their mechanical properties before manufacturing, i.e. strength or stiffness. An example of such designs...
-
Configurational and Conformational Preferences in Stereoselective Acylations of N-Methyl-1,3-diaminopropane with Acyl Chlorides
PublicationEvidence for a stereoinduction profile of the reaction of N-methyl-1,3-diaminopropane with acyl chlorides was provided. A possibility to engage in intramol. CH2···HN and Cl···H-N interactions and the proton migration process to the methylamino group leads to the E secondary amides carrying the N···H+···N or N-H···N bridges, that show unusual spectroscopic images. Empirical relations between the ΔδC chem. shift differences,...
-
Physical and Mechanical Evaluation of Silicone-Based Double-Layer Adhesive Patch Intended for Keloids and Scar Treatment Therapy
PublicationGrowing interest in silicone elastomers for pharmaceutical purposes is due to both theirbeneficial material effect for scar treatment and their potential as drug carriers. Regarding their morphological structure, silicone polymers possess unique properties, which enable a wide range of applicability possibilities. The present study focused on developing a double-layer adhesive silicone film (DLASil) by evaluating its physical...
-
rigid polyurethane foams modified with selected nanofillers
PublicationThe nanofillers: natural montmoryllonite (MMT) - Bentonite, natural MMT modified with a quaternary ammonium salt - Cloisite30B, has been used in rigid polyurethane foams (PUFs). The influence of fillers amounts on processing parameters, physical-mechanical properties (density, water absorption, brittleness and compression strength) and thermal properties (thermal stability, fire behaviours) of such foams has been analysed. The...
-
Photophysics and Halide Quenching of Soret-excited ZnTPPS4- in Aqueous Media
PublicationSteady state S2-S0 and S1-S0 absorption and emission spectra and picosecond S2 decay and S1 fluorescence rise times have been measured for the model porphyrin ZnTPPS4− in water and in aqueous iodide solutions of constant ionic strength. The dynamics of S1 quenching by iodide are well-modeled by a Stern-Volmer mechanism yielding kQ = 1.75 × 109 M−1 s−1. The S2 state is quenched on a ps time scale by a static electron-transfer mechanism...
-
On the application of magnetoelastic properties measureme nts for plastic level determination in martensitic steels
PublicationThe change in the dislocation density, induced by plastic deformation, influences strongly the magnetic domain structure inside the material. Being so, classic parameters, like the coercivity or magnetic permeability, can be a good measure of the deformation level, yet their reliable determination in a non-destructive way in industrial environment is problematic. The magnetoacoustic emission (MAE) which results from the non-180...
-
Corrosion Properties of Dissimilar AA6082/AA6060 Friction Stir Welded Butt Joints in Different NaCl Concentrations
PublicationA solid-state friction stir welding method which is increasingly used in the marine and shipbuilding industry, has been developed to produce welds with high mechanical properties. In seawater, the oxide layer of aluminium is attacked by Cl− ions resulting in its disruption and formation of pitting corrosion. It is particularly important to determine the electrochemical properties of the produced welds and to evaluate the efect...
-
Effect of microstructure on mechanical properties of BA1055 bronze castings
PublicationThe article presents research results performed on aluminum bronze CuAl10Fe5Ni5 (BA1032) castings used for marine propellers. Metallographic studies were made on light microscope and a scanning electron microscope to assess quantitatively and qualitatively the alloy microstructure. It has been shown that the shape, size and distribution of the iron-rich phase precipitates in bronze microstructure significantly affect its mechanical...
-
Temper bead welding of S460N steel in wet welding conditions
PublicationWet welding is the most common method of welding in water environment. It is most often used for repairing of underwater parts of offshore structures. However, the water as a welding environment causes an increase of susceptibility of steels to cold cracking. For underwater constructions high strength low alloy (HSLA) steel are widely used. In wet welding condition a HSLA steel is characterized by high susceptibility to cold cracking....
-
Cellulose Nanomaterials in Biomedical, Food, and Nutraceutical Applications: A Review
PublicationNanotechnology with bionanomaterials have tremendous potential to enhance and utilize for nutrient and bioactive absorption, drug delivery systems, pharmaceutical, and nutraceutical field through various applications. Cellulose nanomaterials are green materials that are obtained from renewable sources and possess exceptional mechanical strength and biocompatibility. The associated unique physical and chemical properties have made...
-
Improvement of the load capacity of the road overpass as a result of repairs after breakage caused by vehicle impacts
PublicationDamage of spans of the overpass caused by impact of underpassing vehicles are a frequent case. Objects that use prefabricated load-bearing elements that are not designed for such impacts are particularly exposed. After impact, such parts suffer extensive damage that need repair. Taking advantages of this recovery actions it is worth to perform strengthening that will protect object against possible future impacts. In this study...
-
Cation sensing by diphenyl-azobenzocrowns
PublicationMetal cations complexation and proton binding by 13- and 16-membered diphenyl-azobenzocrowns and diphenyl-hydroxyazobenzocrowns were studied in acetonitrile using spectroscopic methods: UV–vis spectroscopy, spectrofluorimetry, and 1H NMR spectroscopy. Phenyl moieties in benzene rings were found to affect binding strength alkali and alkaline earth metal cations and hydrogen ion, and affect tautomeric equilibrium of hydroxyazobenzocrowns....
-
Magnetic-field-induced electric quadrupole moments for relativistic hydrogenlike atoms: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function
PublicationWe consider a Dirac one-electron atom placed in a weak, static, uniform magnetic field. We show that, to the first order in the strength of the external field, the only electric multipole moments, which are induced by the perturbation in the atom, are those of an even order. Using the Sturmian expansion of the generalized Dirac-Coulomb Green function we derive a closed-form expression for the electric quadrupole moment induced...
-
Evolution of Physical Properties of RE 3 Ni 5 Al 19 Family (RE = Y, Nd, Sm, Gd, Tb, Dy, Ho, and Er)
PublicationSingle crystals of RE3Ni5Al19 series (RE = Y, Nd, Sm, Gd, Tb, Dy, Ho, and Er) are grown using the Al self-flux method. The crystal structure is examined by both single crystal and powder X-ray diffraction. Physical properties are studied for the first time for RE3Ni5Al19 (RE = Y, Nd, Gd, Tb, Dy, Ho, and Er) by means of magnetic susceptibility, electrical resistivity, and heat capacity measurements. Complex magnetic behaviors, with...
-
A new finite element with variable Young's modulus
PublicationThe Finite Element Method (FEM) is a numerical technique that is well-established in the field of engineering. However, in biological sciences, it is justtaking its first steps. Bone tissue is an example of biological material which isexposed to high loads in its natural environment. Practically every movementof the body results in changing stress levels in the bone. Nature copes with thisvery well but when human intervention is...
-
Badania spawalności stali S460N w środowisku wodnym z wykorzystaniem próby Tekken
PublicationSpawanie w środowisku wodnym niesie ze sobą wiele problemów, wśród których najważniejszym jest skłonność stali do powstawania pęknięć zimnych. O ile w przypadku spawania na powietrzu istnieje wiele metod zapobiegania tym pęknięciom, o tyle pod wodą zastosowanie tych metod jest ograniczone. Z tego powodu konieczne jest określenie skłonności danego materiału do pękania zimnego. W pracy oceniono spawalność drobnoziarnistej...
-
Development of nanoscale morphology and role of viscoelastic phase separation on the properties of epoxy/recycled polyurethane blends
PublicationA novel and cost-effective approach towards the modification of epoxy matrix has been developed using recycled polyurethane for the first time without sacrificing any of the intrinsic properties of the resin. Polyurethane, recycled from waste foam by glycolysis process (RPU), was found to be very effective in improving the properties of the thermosetting resin based on Diglycidyl ether of bisphenol-A (DGEBA). The effect of the...
-
Troubleshooting of the determination of bisphenol A at ultra-trace levels by liquid chromatography and tandem mass spectrometry
PublicationDetermination of trace amounts of bisphenol A (BPA) may cause problems mainly related to the presence of BPA in solvents (even in LC-MS grade), laboratory vessels, and plastic equipment used for sample preparation. Variable and sometimes significant amounts of BPA present in the background cause problems in obtaining good repeatability of measurements at the ultra-trace levels. Such observations (i.e., poor repeatability of results)...
-
Investigation of Mechanical and Microstructural Properties of Welded Specimens of AA6061-T6 Alloy with Friction Stir Welding and Parallel Friction Stir Welding Methods
PublicationThe present study investigates the effect of two parameters of process type and tool offset on tensile, microhardness, and microstructure properties of AA6061-T6 aluminum alloy joints. Three methods of Friction Stir Welding (FSW), Advancing Parallel-Friction Stir Welding (AP-FSW), and Retreating Parallel-Friction Stir Welding (RP-FSW) were used. In addition, four modes of 0.5, 1, 1.5, and 2 mm of tool offset were used in two welding...
-
Processing of Polyester-Urethane Filament and Characterization of FFF 3D Printed Elastic Porous Structures with Potential in Cancellous Bone Tissue Engineering
PublicationThis paper addresses the potential of self-made polyester-urethane filament as a candidate for Fused Filament Fabrication (FFF)-based 3D printing (3DP) in medical applications. Since the industry does not provide many ready-made solutions of medical-grade polyurethane filaments, we undertook research aimed at presenting the process of thermoplastic polyurethane (TPU) filament formation, detailed characteristics, and 3DP of specially...
-
Building Polish space sector – from small islands of excellence to a national innovation ecosystem
PublicationIn the paper a national potential of Poland to build its space industry after joining the European Space Agency (ESA) in 2012 is assessed, based on the series of survey reports published annually by POLSA since 2016. Their methodology was based on the ESA technology tree, classifying all the space-related technical knowhow and allowed identification of the most promising strengths to exploit and shortages to challenge by policymakers...
-
Vietnamese version of the Dual Filial Piety Scale: preliminary validation in a student sample
Publication -
Effect of storing persimmon (Diospyros kaki) fruits under shelf life conditions on selected physical parameters and chemical composition
Publication -
Data Mining Applications and Methods in Medicine
PublicationIn this paper we describe the research area of data mining and its applications in medicine. The origins of data mining and its crucial features are shortly presented. We discuss the specificity of medicine as an application area for computer systems. Characteristic features of the medical data are investigated. Common problems in the area are also presented as well as the strengths and capabilities of the data mining methods....
-
REINFORCED CONCRETE SUPPORTING CONSTRUCTION OF THE STADIUM COVER FOR EURO 2012 IN GDAŃSK
PublicationIn the article structural issues that connected with the reinforced concrete supporting construction of the stadium roofing for EURO 2012 in Gdańsk were described. In the first part of the article the concept of stadium foundation were described. In the second the static - strength analysis for two variants fastening together individual foundation elements were made. The two assumed geometrically different concept of foundation...
-
KOMPOZYTOWY MOST PIESZO - ROWEROWY
PublicationPaper presents the composite foot and cycle bridge developed in FOBRIDGE grant cofinanced by The National Centre for Research and Development and realized by consortium of Gdansk University of Technology (leader), Military University of Technology in Warsaw and ROMA Sp. z o.o. in Toruń. The purpose of the grant was to design a shell type single span foot and cycle bridge made of composite materials, with the assumption of manufacturing...
-
Analysis of EN 1993-1-6 guidelines about determining amplitudes of equivalent imperfections of steel cylindrical shells subjected to uniform external pressure
PublicationCivil engineering structures should be designed with reference to relevant standards. One of them is a Eurocode 3 standard EN 1993-1-6:2007: Design of steel structures Part 1-6: Strength and Stability of Shell Structures. According to this standard, the value of buckling load can be determined using different approaches: classical hand calculations (stress design) and geometrical and material non-linear analysis of an imperfect...
-
Three-Dimensional Fractography for Conventional and Additive Manufactured Steels After Bending-Torsion Fatigue
PublicationIn this study, fracture surface topography parameters were measured to investigate the effects of multiaxial loading. In order to assess the metrological aspects of fracture for notched specimens made of high-strength steels processed by both conventional and additively manufacturing (AM) techniques, an optical surface profilometer was used. Three bending moment to torsion moment ratios (B/T) were studied, i.e. 2, 1 and 2/3. The...
-
PROBLEMY ZWIĄZANE Z ZASTOSOWANIEM NANOTECHNOLOGII W TERMOIZOLACJI BUDYNKÓW
PublicationBudownictwo i architektura były zawsze ściśle związane z rozwojem technologicznym a ciągły postęp w badaniach nad inżynierią materiałową pozwalał na uzyskiwanie bardziej wydajnych i wytrzymałych materiałów. Dotyczy to nie tylko elementów konstrukcyjnych budynku ale także technologii związanych z jego wykończeniem. Obecnie coraz większą rolę w budownictwie i architekturze odgrywa pojęcie nanotechnologii. Dziedzina nauki, zdawałoby...
-
Personal Entrepreneurial Potential in the Opinion of Young Women Entering the Labor Market
PublicationIn the current economic situation in Europe the need to stimulate entrepreneurship, with the special attention to develop the entrepreneurship among women, is clearly emphasized. The action is mostly taken to encourage the use of internal potential of possible future entrepreneurs. Do we know what the potential really is ? The presented article deals with the issues of women's entrepreneurship, demonstrating results of self assessment...
-
Selecting the optimum location for logistics facilities using Solver
PublicationSiting logistics facilities strategically in the most costeffective geographic location is one of the key decisions a contemporary company will make. The aim of the paper is to present a solution to this problem using the Solver add-on. In the case study discussed in the paper, the company’s central warehouse location was selected based on the classic location theory, which addresses the need to minimize the cost of transport....
-
In vitro biodegradation of bacterial nanocellulose under conditions simulating human plasma in the presence of selected pathogenic microorganisms
PublicationThe Biodegradability of bacterial nanocellulose (BNC) was assessed based on a change in its properties under conditions simulating human plasma in the presence or absence of the pathogens Staphylococcus aureus, Candida albicans and Aspergillus fumigatus. It was shown that the dry mass of BNC did not change during 6 months of incubation, except for samples stored in the presence of moulds, where the dry mass reduced by 40 %. The...
-
Support for argument structures review and assessment
PublicationArgument structures are commonly used to develop and present cases for safety, security and for other properties of systems. Such structures tend to grow excessively, which causes problems with their review and assessment. Two issues are of particular interest: (1) systematic and explicit assessment of the compelling power of an argument, and (2) communication of the result of such an assessment to relevant recipients. The paper...
-
Influence of a Radio Frequency on RF Fingerprinting Accuracy Based on Ray Tracing Simulation
PublicationIn this paper the influence of a radio signal frequency on performance of Indoor Positioning System based on fingerprinting has been examined using ray-tracing simulations. It has been simulated how spatial distribution of an RF signal strength change with the signal’s frequency. The results were used to show its’ impact on the behavior of localization algorithms that are employing RSS measurements to determine node’s position...
-
The Method of a Two-Level Text-Meaning Similarity Approximation of the Customers’ Opinions
PublicationThe method of two-level text-meaning similarity approximation, consisting in the implementation of the classification of the stages of text opinions of customers and identifying their rank quality level was developed. Proposed and proved the significance of major hypotheses, put as the basis of the developed methodology, notably about the significance of suggestions about the existence of analogies between mathematical bases of...
-
Joints Of Steel Sandwich Structures
PublicationSteel sandwich structures are perceived as alternatives to single-skin welded structures in the shipbuilding industry due its advantages like significant reduction of mass in relation to typical single skin structure. However, beside problems with their strength properties itself, applications in real structures requires of solving the problem of joining, both for connection sandwich to sandwich as well as sandwiches to single-shell...
-
Geospatial Coverage and Signal Quality Measurements of Terrestrial DAB+ Network in Northern Poland
PublicationModern signal coverage maps are prepared based on industry-standard radio propagation models, which take into account a number of parameters, including: type of antenna, distance from the transmitter, type of terrain, etc. However, such simulations are prone to location-specific inaccuracies, and should be verified with in-situ measurements. This paper presents results of a field test of a terrestrial DAB+ (Digital Audio Broadcasting...
-
MULTI-CRITERIA COMPARATIVE ANALYSIS OF THE USE OF SUBTRACTIVE AND ADDITIVE TECHNOLOGIES IN THE MANUFACTURING OF OFFSHORE MACHINERY COMPONENTS
PublicationThe dynamic development of additive manufacturing technologies, especially over the last few years, has increased the range of possible industrial applications of 3D printed elements. This is a consequence of the distinct advantages of additive techniques, which include the possibility of improving the mechanical strength of products and shortening lead times. Offshore industry is one of these promising areas for the application...
-
Metallurgical characterization and high-temperature tensile failure of Inconel 617 alloy welded by GTAW and SMAW—a comparative study
PublicationTwo types of the weld joint of Inconel 617 alloy were produced using gas tungsten arc welding (GTAW) and shielded metal arc welding (SMAW) processes with ERNiCrCoMo-1 filler metal and ENiCrCoMo-1 electrode, respectively. The weld metal showed the segregation of the principle alloying elements like Mo and Cr along the inter-dendritic spaces, triggering the formation of secondary phases. The microstructure characterization of the...
-
A dissimilar welded joint of grade 92 steel and AISI 304L steel obtained using IN82 buttering and IN617 fller: relationship of microstructure and mechanical properties
PublicationUnfavourable operating conditions of equipment in the energy industry resulting from high-temperature loads determine the need to use special materials and technological solutions, including welding procedures. In this article, buttering using IN82 (ERNiCr-3) consumables was proposed as a method to improve the weldability of grade 92 steel joined by the gas tungsten arc welding (GTAW) process with AISI 304L (IN617 fller). The...
-
Composite as a Material of the Future in the Era of Green Deal Implementation Strategies
PublicationComposite materials have become synonymous with modernity, desired in nearly every aspect of our daily lives, from simple everyday objects to sanitary facilities, pipelines, the construction of modern sewer networks, their renovation, water supply, and storage reservoirs, to complex structures—automotive, planes, and space science. Composites have seen a considerable rise in attention owing to their characteristics, durability,...
-
Investigations on fracture in reinforced concrete beams in 3-point bending using continuous micro-CT scanning
PublicationThis study explores a fracture process in rectangular reinforced concrete (RC) beams subjected to quasi-static three-point bending. RC beams were short and long with included longitudinal reinforcement in the form of a steel or basalt bar. The ratio of the shear span to the effective depth was 1.5 and 0.75. The focus was on the load–deflection diagram and crack formation. Three-dimensional (3D) analyses of the size and distribution...
-
Ground Tire Rubber Filled Flexible Polyurethane Foam—Effect of Waste Rubber Treatment on Composite Performance
PublicationThe application range of flexible polyurethane (PU) foams is comprehensive because of their versatility and flexibility in adjusting structure and performance. In addition to the investigations associated with further broadening of their potential properties, researchers are looking for new raw materials, beneficially originated from renewable resources or recycling. A great example of such a material is ground tire rubber (GTR)—the...
-
Comparison of Polish and Danish Approach to Promotion of Cycling
PublicationThe article describes two different approaches to promotion of cycling from Denmark and Poland. In the former the promotion locally from 2009 to 2015 has been supported financially by the national government and where initiatives partly have been financed by the national level. In Poland, the promotion has been implemented often as a result of bottom up initiatives and financed solely on local level often with the support of EU...