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Cross-Linking, Morphology, and Physico-Mechanical Properties of GTR/SBS Blends: Dicumyl Peroxide vs. Sulfur System
PublikacjaIn this work, ground tire rubber and styrene–butadiene block copolymer (GTR/SBS) blends at the ratio of 50/50 wt%, with the application of four different SBS copolymer grades (linear and radial) and two types of cross-linking agent (a sulfur-based system and dicumyl peroxide), were prepared by melt compounding. The rheological and cross-linking behavior, physico-mechanical parameters (i.e., tensile properties, abrasion resistance,...
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Analytical approach for membrane action in laterally-restrained reinforced concrete square slabs under uniformly distributed loads
PublikacjaLaterally-restrained reinforced concrete slabs can mobilise compressive membrane action and subsequent tensile membrane action under extreme loading conditions, thereby enhancing the load resistance under uniformly distributed loads. Previous analytical study focuses primarily on tensile membrane action in simply-supported slabs. This paper describes an analytical approach for membrane action in laterally-restrained square slabs....
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Simple empirical formula to estimate the main geomechanical parameters of preplaced aggregate concrete and conventional concrete
PublikacjaPreplaced aggregate concrete (PAC) or two-stage concrete is a specific type of concrete successfully employed in many projects including underwater concrete structures, massive concrete structures, structures made of reinforced concrete, and improvement of concrete structures. PAC is significantly different than the conventional concrete. In this type of concrete, aggregates are initially poured into the mold, the voids between...
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Assessment of the application of CEM III with exposed aggregate as an alternative to CEM I for road pavements
PublikacjaThe article presents a results of study on the impact of replacing CEM I SR3/NA by CEMIII/A LH/HSR/NAon the mechanical properties and durability of pavement concrete with exposed aggregate. Was used granite aggregate and washed sand. Water/cement () ratio in the tested concretes constituted 0.35 and 0.4 and part of the cement was replaced with a 5% addition of natural pozzolana – zeolite. Compressive strength tests were performed...
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Comparative Analysis of the Cofee and Cocoa Industry By‑Products on the Performance of Polyethylene‑Based Composites
PublikacjaThe application of plant-based by-products from the food industry as minimally processed functional fillers for polymeric composites is an increasingly popular trend among researchers and manufacturers. While minimizing the preprocessing of lignocellulosic fillers leads to an increase in the sustainability of the overall composite and a decrease of the carbon footprint, filler modification is usually indispensable to obtaining...
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Laser Dissimilar Welding of AISI 430F and AISI 304 Stainless Steels
PublikacjaA dissimilar autogenous laser welded joint of AISI 430F (X12CrMoS17) martensitic stainless steel and AISI 304 (X5CrNi18-10) austenitic stainless steel was manufactured. The welded joint was examined by non-destructive visual testing and destructive testing by macro- and microscopic examination and hardness measurements. With reference to the ISO 13919-1 standard the welded joint was characterized by C level, due to the gas pores...
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Thermal Imaging Aided Assessment of a State of Equipment Under Test and its Protecting Elements
PublikacjaIn the paper the investigation results using thermal imaging methods are presented. The examined is a state of equipment under test and its protecting components. The estimations are done for the chosen protecting elements during surge immunity testing. The results show that the thermal imaging methods are useful for early detection of possible damage of a device being tested
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CRVG - a new model for wireless networks topology generation
PublikacjaThis paper presents a new model of wireless network topology generator. Its main advantage is the possibility of relatively sparse networks generation. Because no iteration is needed, the model can be used for massive generation of networks for testing. The topological properties of produced graphs place them in the class of scale free networks, resembling real ones.
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Theoretical Model of Acoustic Wave Propagation in Shallow Water
PublikacjaThe work is devoted to the propagation of low frequency waves in a shallow sea. As a source of acoustic waves, underwater disturbances generated by ships were adopted. A specific feature of the propagation of acoustic waves in shallow water is the proximity of boundaries of the limiting media characterised by different impedance properties, which affects the acoustic field coming from a source situated in the water layer “ deformed”...
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High Growth Aspirations of Nascent Entrepreneurs: Why Do They Fall?
PublikacjaIntention-based research become more and more popular in various domains, including entrepreneurship. Achieving growth by a business must be planned or at least consciously accepted by the business owner. That is why it is vital to take growth intentions into account when trying to predict growth of business. Personal attitude of an entrepreneur towards growth is important from the very beginning of business operations or even...
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PHONEME DISTORTION IN PUBLIC ADDRESS SYSTEMS
PublikacjaThe quality of voice messages in speech reinforcement and public address systems is often poor. The sound engineering projects of such systems take care of sound intensity and possible reverberation phenomena in public space without, however, considering the influence of acoustic interference related to the number and distribution of loudspeakers. This paper presents the results of measurements and numerical simulations of the...
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A Centralized Reputation System for MANETs Based on Observed Path Performance
PublikacjaA reputation system for MANETs is described that attempts to deduce nodal trustworthiness (forwarding behaviour) from observed end-to-end path performance. The trustworthiness deduction algorithm produces interval estimates and works well if node misbehaviour is not selec-tive with respect to traversing paths. Nodal reputation levels are next calculated in the spirit of generous tit-for-tat so as to best reflect momentary nodal...
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COMPARATIVE ANALYSES OF INTERNATIONALIZATION OF KAZAKHSTAN ENTERPRISES
PublikacjaThis paper presents the instruments of internationalization of enterprises operating within the Eurasian Economic Union. Research contains answers of 108 enterprises exporters located in the Republic of Kazakhstan. The purpose of the paper is to show the main forms of the internationalization of enterprises in Kazakhstan. The paper also presents the following instruments of enterprises’ internationalization including: indirect...
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Examples of Taxation on Real Estate Properties as an Long-term Investment Asset. Description of Situation in Selected European Countries
PublikacjaReal estate properties have become the alternative asset for long-term savings and investments. Such investment however is strictly related to risk inter alia taxation policy. The following article describes and discusses both theoretical and practical aspects of long-term investment taxation imposed on real estate market in selected European countries. The article presents the analyses of the taxes including its functions, mechanisms...
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Conversion of Biomass and Municipal Wastes into Syngas and Hydrogen using Highly Preheated Agent (HTAG)
PublikacjaGasification is considered to be one of the most promising energy recovery technologies for the widespread utilization of biomass and wastes. During this process raw feedstock is converted into a combustible gas, which can then be burnt to produce thermal energy, or to run engines for mechanical or electrical power. The studies of biomass gasification demonstrate it as a friendly alternative to fossil fuels as one of renewable...
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Self-compacting grout to produce two-stage concrete
PublikacjaTraditional concrete (TC) is primarily composed...
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Structure-property relationships in peroxide-assisted blends of poly(ε-caprolactone) and poly(3-hydroxybutyrate)
PublikacjaPoly(ε-caprolactone) and poly(3-hydroxybutyrate) (PCL/PHB) blends in two weight ratios (75/25 and 50/50) were reactively compatibilized in the presence of di-(2-tert-butyl-peroxyisopropyl)-benzene and dicumyl peroxide as free radical initiators. Rheological, mechanical, thermal properties and morphological features, as well as the chemical structure of PCL/PHB blends were investigated. It was found that regardless of PCL/PHB blend...
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Mechanical Strength of MV Ship-switchgear During Fault Arc
PublikacjaIn the paper the analysis of pressure stressed in enclosure during fault arc inside switchgear is pre-sented as well. There is introduced the method based on determining stresses which are sum of tensile stresses (membrane) and deflection stresses. For tensile stresses nalysis the energy method, for unrestrainedly supported rectangular plate, was used. In the further part of the paper, the calculations and measurements results...
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Preparation, morphology and properties of natural rubber composites filled with untreated short jute fibres
PublikacjaGreen composites were obtained by incorporation of short jute fibres in natural rubber matrix using a laboratory two-roll mill. The influence of untreated fibre content (1, 2.5, 5, 7.5 and 10 phr) on the mechanical properties, dynamic mechanical properties, swelling properties was examined. The behaviour of prepared green composites under cyclic compression was also investigated. Fibre dispersion in rubber matrix was studied by...
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Rotational Molding of Linear Low-Density Polyethylene Composites Filled with Wheat Bran
PublikacjaApplication of lignocellulosic fillers in the manufacturing of wood polymer composites (WPCs) is a very popular trend of research, however it is still rarely observed in the case of rotational molding. The present study aimed to analyze the impact of wheat bran content (from 2.5 wt.% to 20 wt.%) on the performance of rotationally-molded composites based on a linear low-density polyethylene (LLDPE) matrix. Microscopic structure...
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Mechanical Properties, Microstructure and Surface Quality of Polypropylene Green Composites as a Function of Sunflower Husk Waste Filler Particle Size and Content
PublikacjaAgricultural waste is a still untapped source of materials that can, in case of proper utilization, significantly improve the sustainability of polymers and their composites. In this work, polymer composites based on isotactic polypropylene were produced incorporating ground sunflower husk in the amount of 10 wt% and 20 wt%. The work’s main objective is to evaluate how preliminary fractioning of this agricultural waste filler affects...
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Thermoplastic starch nanocomposites using cellulose-rich Chrysopogon zizanioides nanofibers
PublikacjaGreen thermoplastic starch (TPS) nanocomposite films aided by cellulose nanofibers (CNFs) from Chrysopogon zizanioides roots were developed and characterized. When compared to other lignocellulosic fibers, Chrysopogon zizanioides roots revealed exceptionally high cellulose content (~48%). CNFs were separated using an environmentally friendly acid isolation technique that included three stages: (i) alkali treatment; (ii) bleaching;...
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GTR/Thermoplastics Blends: How Do Interfacial Interactions Govern Processing and Physico-Mechanical Properties?
PublikacjaIn this work, GTR/thermoplastics blends (in ratio 50/50 and 75/25 wt.%) were prepared by melt-compounding in an internal mixer. During research, trans-polyoctenamer rubber (TOR), ethylene-vinyl acetate copolymer (EVA), ethylene-octene copolymer (EOC), and linear low-density polyethylene (LLDPE), were used in their thermoplastic phase. Microstructure and processing-performance property interrelationships of the studied materials...
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Laser Welding of UNS S33207 Hyper-Duplex Stainless Steel to 6061 Aluminum Alloy Using High Entropy Alloy as a Filler Material
PublikacjaThe high entropy alloy (HEA) filler used during the fabrication method determines the reliability of HEAs for steel-aluminum dissimilar alloy configuration. HEAs have a direct impact on the formation of intermetallic compounds (IMC) formed by the interaction of iron (Fe) and aluminum (Al), and influence the size of the joint’s interaction zone. A novel welding process for Fe-Al alloy joints was developed to prevent the development...
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Insights into Stoichiometry Adjustments Governing the Performance of Flexible Foamed Polyurethane/Ground Tire Rubber Composites
PublikacjaPolyurethanes (PU) are widely applied in the industry due to their tunable performance adjusted by changes in the isocyanate index—stoichiometric balance between isocyanate and hydroxyl groups. This balance is affected by the incorporation of modifiers of fillers into the PU matrix and is especially crucial for PU foams due to the additional role of isocyanates—foaming of the material. Despite the awareness of the issue underlined...
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The effectivness of fault detection in common rail injectors examination methods
PublikacjaThe article presents the effectiveness tests of fault detection in common rail injectors. 40 injectors with different wear levels were tested. Testing was made on two test benches of a completely different design. Research includes comparison of accuracy, reproducibility and testability to detect specific defects. A device was created for visualization of the fuel injector spraying steam.
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A new method for measuring the psychoacoustical properties of tinnitus
Publikacjainformation, select the tinnitus treatment and quantitatively substantiate its effects, the measurement of the Tinnitus psychoacoustic parameters should be made an inherent part of the Tinnitus therapy. Methods For this purpose the multimedia-based sound synthesizer has been proposed for testing tinnitus and the results obtained this way are compared with the outcome of the audiometer-based Wilcoxon test. The method has been verified...
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Experimental and computational study on mechanical behaviour of carpentry corner log joints
PublikacjaThis work concerns experimental and numerical research on carpentry joints used in historic wooden buildings in southeastern Poland and western Ukraine. These structures are mainly sacred buildings, and the types of corner log joints characteristic of this region are primarily saddle-notch and dovetail joints; thus, these two types of joints were analysed in this study. The modelling of historic timber structures is a complex...
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Opracowanie procedury i badania wytrzymałościowe połączeń spawanych pomiędzy rurą kwadratowa a elementami giętymi na zimno ze stali S355 oraz testowanie połączeń o grubości 4, 6, 8mm typu S355
PublikacjaCelem pracy było: - opracowanie procedury badania wytrzymałości połączeń spawanych rozciąganych w kierunku prostopadłym i w kierunku równoległym (ścinanych) do osi spoiny. Spoiny te łączyły elementy rur kwadratowych o różnej grubości z elementami w kształcie ceownika giętymi na zimno. - wykonanie próbek do badań wytrzymałościowych wyciętych z elementów spawanych dostarczonych przez Zakład Produkcyjny firmy Borga obciążonych prostopadle...
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Usability Techniques Possible to Use in Diagnostic Tools Interface Improvement
PublikacjaThe development of diagnostic tools has caused a rapid increase in the amount of information generated and presented, necessitating the use of computer displays as an interface to data presentation and the use of modern diagnostic tools. The paper presents methods for testing usability that can be used in designing and improving the quality of interfaces of modern diagnostic tools that use communication through graphical user interfaces.
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Immunity of residual current devices to the impulse leakage current in circuits with variable speed drives
PublikacjaThis paper concerns reliability of supply in variable speed drive circuits with residual current devices. During normal operation of these circuits high value of leakage current causes unwanted tripping of residual current devices. Immunity of residual current devices to the impulse leakage current should be evaluated. The system for testing of residual current devices and results of the test are presented
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Application of the Bodner-Partom constitutive equations for modelling of the technical fabric Valmex used for the hanging roof of the Forest Opera in Sopot
PublikacjaThe study of an inelastic properties of the technical fabric Valmex used for 20 years as the roof structure of the Forest Opera in Sopot (Poland) is presented. The uniaxial tensile laboratory tests with constant strain rate have been conducted and analysed. Parameters of the Bodner-Partom constitutive model have been identified and verified by numerical simulations. Two approaches of the parameters identification have been proposed:...
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PROCESSING, MECHANICAL AND THERMAL PROPERTIES OF RECYCLED LOW-DENSITY POLYETHYLENE STREAMS
PublikacjaThe recycling of plastics is currently one of the most significant industrial challenges. Due to the enormous amounts of plastic wastes generated by various industry branches, it is essential to look for the potential methods of their utilization. Nevertheless, for the efficient application of recycled materials it is crucial to analyze their performance. Therefore, in presented paper we investigated the processing (melt flow index),...
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Mechanical properties of the human stomach under uniaxial stress action
PublikacjaThe aim of this study was to estimate the range of mechanical properties of the human stomach in order to use the collected data in numerical modelling of surgical stapling during resections of the stomach. The biomedical tests were conducted in a self-developed tensile test machine. Twenty-two fresh human stomach specimens were used for the experimental study of its general strength. The specimens were obtained from morbidly obese...
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Ocena wpływu polityki zdrowotnej na jakość życia starzejącego się społeczeństwa w krajach UE
PublikacjaStarzenie się społeczeństw w Europie powoduje wiele problemów społecznych i ekonomicznych. Polityka zdrowotna i jakość opieki zdrowotnej wpływają na stan zdrowia osób starszych, a tym samym na jakość ich życia. Artykuł jest próbą oceny polityki zdro-wotnej w krajach Unii Europejskiej w kontekście jakości życia. Wykorzystano metodę Data Envelopment Analysis i koncepcję helmsmana, powszechnie stosowane do oceny różnych rodzajów polityki....
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Zarządzanie marką w dobie nadpodaży
PublikacjaArtykuł poświęcony jest wskazaniu wyzwań stojących przed menedżerami marki wobec nadpodaży marek, produktów i informacji, będącymi pośrednią przyczyną marginalizacji marketingu jako funkcji wielu przedsiębiorstwach o organizacji „silosowej”, gdzie marketing często ograniczany jest do funkcji promocji. Wspomniane okoliczności, zdaniem autorki, mogą prowadzić zarówno do dalszej marginalizacji marketingu w wyniku spadku znaczenia...
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To meet or to connect? Face-to-face contacts vs ICT in cluster organisations
PublikacjaThe main purpose of the paper is to explore how cluster organisations (COs) take advantage of direct (F2F) and indirect (ICT) contacts in fulfilling their main roles. The paper addresses the research question: “How important are Information and Communication Technologies at each level of advancement of cluster cooperation?” The research was conducted in 2016 in four purposefully selected cluster organisations representing metal...
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PHYSICAL MODELLING OF GEOTECHNICAL STRUCTURES IN PORTS AND OFFSHORE
PublikacjaThe physical modelling of subsoil behaviour and soil-structure interaction is essential for the proper design of offshore structures and port infrastructure. A brief introduction to such modelling of geoengineering problems is presented and some methods and experimental devices are described. The relationships between modelling scales are given. Some examples of penetration testing results in centrifuge and calibration chamber...
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Process of Medical Dataset Construction for Machine Learning-Multifield Study and Guidelines
PublikacjaThe acquisition of high-quality data and annotations is essential for the training of efficient machine learning algorithms, while being an expensive and time-consuming process. Although the process of data processing and training and testing of machine learning models is well studied and considered in the literature, the actual procedures of obtaining data and their annotations in collaboration with physicians are in most cases...
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Export diversification and economic development: A dynamic spatial data analysis
PublikacjaThis paper contributes to the empirical literature on the relationship between “export variety” (export diversification) and economic development by relaxing the assumption of cross-country independence and allowing for spatial diffusion of shocks in observed and unobserved factors. Export variety is measured for a balanced panel of 114 countries (1992–2012) using very detailed information on their exports (HS 6-digit product level)....
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Guided ultrasonic waves for detection of debonding in bars partially embedded in grout
PublikacjaThis paper deals with theoretical, numerical and experimental investigations of guided wave propagation in multilayered cylindrical bars with pre-existing debonding. The research focuses on a complex description of the nature of the wave phenomena occurring in a debonded specimen with a special emphasis on the influence of the location of damage on the wave conversion and diffraction. Experimental non-destructive and destructive...
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Modeling the Effects of Slowly Biodegradable Substrate at Large WWTP in Northern Poland
PublikacjaThe essential study was divided into two parts: experimental investigation and mathematical modeling using special platform to computer simulations. In the first part of research an innovative measurement procedure for an indirect determination of the effect of biodegradable particulate and colloidal Xs substrate was developed and implemented. The results of laboratory tests were used futher to verify the mechanism of the hydrolysis...
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Endoscopic image processing and analysis of pistons' service failures of marine diesel engines
PublikacjaThe paper deals with diagnostic issues concerning endoscopic examinations of working spaces within marine diesel engines. In the beginning, endoscopy apparatus being on laboratory equipment of the Department of Ship Power Plants of Gdansk University of Technology has been characterized. The endoscopy considerations have been focused on theoretical bases of a digital image processing and especially - on the "Shadow" measurement...
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Structural and optical investigations of sol-gel derived lithium titanate thin films
Publikacjain this paper structural and optical studies of lithium titanate (lto) thin films are presented. nanocrystalline thin films with 800 nm thickness were prepared by sol-gel method. to examine the influence of the annealing time on as-prepared films crystallization, the coatings were heated at 550 °c for 10, 20 and 80 h. structure of manufactured thin films was investigated using x-ray diffraction (xrd). the most visible lithium titanate...
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The impact of domestic and foreign competition on sectoral growth: a cross-country analysis
PublikacjaThis paper examines the impact of competition on the total factor productivity (TFP) of 21 manufacturing sectors in eighteen OECD countries over the period of time 1990–2006. We assume that the source of TFP growth can be either domestic or foreign innovation or technology transfer from the technological frontier. Trade openness, R&D, and human capital can have two effects: a direct effect on TFP (e.g., through innovation) and...
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Implementation of an Adaptive Method for Changing the Frequency Division of the Counter Clock Signal in a Frequency-to-Code Converter
PublikacjaProcessing physical quantities into an indirect signal is a standard method of transferring information about the measured quantity to the master system, which analyzes the data obtained from the acquisition system. The intermediate signal is very often the voltage, but another transmission medium can be the frequency of the output signal of the “physical quantity-to-frequency” converter. The article presents the implementation...
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Transdermal transport of collagen and hyaluronic acid using water in oil microemulsion
PublikacjaCollagen and hyaluronic acid (HA) are biopolymers that affect the appearance and condition of the skin. Delivery of these compounds into the skin is highly challenging since have a number of disadvantageous properties, such as high molecular weight and hydrophilicity. Here, we evaluated the transdermal penetration of low and high molecular weight collagen and HA from microemulsions. A number of microemulsion formulations, differing...
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Classification of Urban Regeneration Participants as a Basis for Identification of Construction Investment's Risk Sources
PublikacjaOn the basis of the conducted research it can be concluded that the majority of the existing urban regeneration problems are revealed by the lack of an in-depth analysis of sources and risk factors. For the above reasons, the subject of this study is classification of urban regeneration's participants as a basis for identification of construction investment's risk sources. The research methodology is based on an in-depth analysis...
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Uncertainty Quantification in Experimental Structural Dynamics Identification of Composite Material Structures
PublikacjaComposite materials are widely used in manufacture of aerospace and wind energy structural components. These load carrying structures are subjected to dynamic time-varying loading conditions. Robust structural dynamics identification procedure impose tight constraints on the quality of modal models estimates obtained from vibration experiments. Modal testing results are influenced by numerous factors introducing uncertainty to...
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Crack monitoring in concrete beams under bending using ultrasonic waves and coda wave interferometry: the effect of excitation frequency on coda
PublikacjaConcrete is one of the most widely used construction materials in the world. In recent years, various non-destructive testing (NDT) and structural health monitoring (SHM) techniques have been investigated to improve the safety and control of the current condition of concrete structures. This study focuses on micro-crack monitoring in concrete beams. The experimental analysis was carried out on concrete elements subjected to three-point...