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Search results for: PIGMENT STABILITY
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Metal accumulation in the human uterus varies by pathology and smoking status
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The geodetic monitoring of the engineering structure – a practical solution of the problem in 3D space
PublicationThe study raises the issues concerning the automatic system designed for the monitoring of movement of controlled points, located on the roof covering of the Forest Opera in Sopot. It presents the calculation algorithm proposed by authors. It takes into account the specific design and location of the test object. High forest stand makes it difficult to use distant reference points. Hence the reference points used to study the stability...
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Mechanical response of human thoracic spine ligaments under quasi-static loading: An experimental study
PublicationPurpose This study aimed to investigate the geometrical and mechanical properties of human thoracic spine ligaments subjected to uniaxial quasi-static tensile test. Methods Four human thoracic spines, obtained through a body donation program, were utilized for the study. The anterior longitudinal ligament (ALL), posterior longitudinal ligament (PLL), capsular ligament (CL), ligamenta flava (LF), and the interspinous ligament and...
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A Control Theoretical Approach to Spectral Factorization is Unstable
PublicationLocal stability analysis of a recently proposed recursive feedback-based approach to spectral factorization is performed. The method is found not to give stability guarantees. Interestingly enough, its global behavior often allows one to obtain reasonable approximations of spectral factorizations if a suitable stopping criterion is employed.
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The energy concept of money
PublicationPurpose: This paper aims to provide the literature review seeking an answer whether energy can be used as a universal equivalent instead of money. Methodology: The author conducted a review of available literature and data sources related to the money theory and energy concept of money. Findings: It was found that the definition of energy as a general equivalent has a contextual and dynamic nature, and this field’s consolidation...
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Effects of Storing Flux-Cored Wires under Various Conditions
PublicationWelding processes involving the use of flux-cored wires are becoming increasingly popular, particularly in shipbuilding as well as in off-shore and civil engineering. The article presents characteristics of the welding process, its areas of application as well as advantages and disadvantages (e.g. necessity of ensuring appropriate conditions for the storage of filler metal wires). The satisfaction of quality-related requirements...
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Comparison of state feedback and PID control of pressurizer water level in nuclear power plant
PublicationThe pressurizer water level control system in nuclear power plant with pressurized water reactor (PWR) is responsible for coolant mass balance. The main control goal is to stabilize the water level at a reference value and to suppress the effect of time-varying disturbances (e.g. coolant leakage in primary circuit pipeline system). In the process of PWR power plant operation incorrect water level may disturb pressure control or...
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Buckling analysis of a non-concentric double-walled carbon nanotube
PublicationOn the basis of a theoretical study, this research incorporates an eccentricity into a system of compressed double-walled carbon nanotubes (DWCNTs). In order to formulate the stability equations, a kinematic displacement with reference to the classical beam hypothesis is utilized. Furthermore, the influence of nanoscale size is taken into account with regard to the nonlocal approach of strain gradient and the van der Waals interaction...
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Inhibition of amyloid fibril formation of hen egg white lysozyme by trimethylamine N-oxide at low pH
PublicationIn vitro inhibition of the formation of fibrous aggregates of proteins (amyloids) has gained increasing attention due to the number of diseases associated with protein misfolding and fibrillation. An interesting group of compounds for which pronounced activity against this phenomenon can be expected consists of low molecular weight substances (osmolytes) which have the ability to change protein stability. Here we investigate the...
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Analytical modeling of electric drives for vehicle traction control systems
PublicationWheel-torque control bandwidth in vehicle dynamics model is crucial in evaluating optimal tracking ability of tire slip and in analysis of control system stability. Electric drives’ control dynamics are influenced by timing of digital control events, e.g. by sampling instant of motor currents. Reflecting this timing in drive analytical models is therefore important for analysis of vehicle traction systems. The paper considers five...
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Biological responses to environmental contamination. How can metal pollution impact signal honesty in avian species?
PublicationEnvironmental pollution, for example with metals, can significantly affect the ecosystem balance leading to severe changes. Biologically active pigments are relevant for the appearance and condition of birds. Melanin and carotenoid particles are the most frequently deposited pigments in avian integument. They are responsible for the majority of colors of bird plumage. The phenotypic expression can be affected by metal contamination....
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Ziarna i mikroziarna diamentowe. Rodzaje ścierniw i przykłady zastosowania
PublicationW książce zawarto podstawowe informacje technologiczne i wyniki prac nad ziarnami i mikroziarnami diamentowymi. Przedstawiono właściwości mechaniczne, termiczne, chemiczne, magnetyczne, elektryczne i optyczne diamentu. Omówiono pochodzenie diamentów, charakteryzując diamenty naturalne oraz wytwarzane w statycznych warunkach wysokiego ciśnienia i temperatury oraz w warunkach dynamicznych. Scharakteryzowano diamentowe kompozyty polikrystaliczne,...
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Gaining knowledge through experience: developing decisional DNA applications in robotics
PublicationOmówiono nowatorskie podejscie do zastosowania wiedzy opartej na doświadczeniu i budowie decyzyjnego DNA w obszarach związanych z robotyką.In this article, we explore an approach that integrates Decisional DNA, a domain-independent, flexible, and standard knowledge representation structure, with robots in order to test the usability and suitability of this novel knowledge representation structure. Core issues in using this Decisional...
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Thermodynamics of solid phases containing rare earth oxides
PublicationRare earth elements (RE) are incorporated into a large variety of complex oxide phases to provide tailored mechanical, electrical, optical, and magnetic properties. Thermodynamics control phase stability, materials compatibility in use, corrosion, and transformation. This review presents, in one compilation, the thermodynamic properties of a large number of such materials and discusses systematic trends in energetics and the factors...
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The Role of Proteins in Food
PublicationThis chapter describes the effect of proteins on the sensory attributes and the biological value and safety of foods. The role of proteins depends on their amino acid composition and structure, on changes due to storage and processing, as well as on interactions with other food components. The effect on the sensory quality of foods is brought about by hydrophobicity, solubility, water holding capacity, gelling, film formation,...
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A novel in vitro assay for assessing efficacy and toxicity of antifungals using human leukaemic cells infected with Candida albicans
PublicationAims: This study describes a novel in vitro assay that simultaneously determines antifungal efficiency and host cell toxicity using suspensions of human leukaemic cells (HL-60) infected with Candida albicans. Methods and Results: The effect of Candida infection on host cell viability was evaluated by the microscopy of trypan blue-stained cells and lactate dehydrogenase (LDH) activity. The in vitro ‘drug potency assay’ utilized...
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Freelance technical writing application for a job which I did not get.
PublicationIn this essay I am going to explore the different ways in which developments in engineering technology and materials science have improved the quality of learning and at the same time somewhat diminished students innate intellectual ability which came as the result of what we know as A.I. According to wikipedia.org the word "education" comes from the conjunction of a Latin words "I lead" or "duco" meaning "I...
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Lower rim substituted tert-butylcalix[4]arenes (II). Complexing ability of5,11,17,23-tetra-tert-butyl-25,26,27,28-tetrakis-O-(piperidinylcarbonyl)me- thylenecalix[4]arene. The crystal structures of the ligand and its sodium complex
PublicationSyntezowano kompleksy wymienionego w tytule liganda z chlorkiem sodu i azotanami itru(III), lantanu(III), samaru(III) i gadolinu(III) w reakcji liganda i odpowiedniej soli, które charakteryzowano za pomocą widm IR, UV-vis,1H NMR, FAB-MS, a także za pomocą analizy elementarnej. W reakcji wymiany z kompleksu z sodem otrzymywano kompleksy z lantanowcami. Określono strukturę krystaliczną wolnego liganda i jego kompleksu z sodem za...
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Development of potential candidate reference materials for drugs in bottom sediment, cod and herring tissues
PublicationRegular use of a reference material and participation in a proficiency testing program can improve the reliability of analytical data. This paper presents the preparation of candidate reference materials for the drugs metoprolol, propranolol, carbamazepine, naproxen, and acenocoumarol in freshwater bottom sediment and cod and herring tissues. These reference materials are not available commercially. Drugs (between 7 ng/g and 32...
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On the use of leading safety indicators in maritime and their feasibility for Maritime Autonomous Surface Ships
PublicationAlthough the safety of prospective Maritime Autonomous Surface Ships will largely depend on their ability to detect potential hazards and react to them, the contemporary scientific literature lacks the analysis of how to achieve this. This could be achieved through an application of leading safety indicators. The aim of the performed study was to identify the research directions of leading safety indicators in three safety-critical...
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The impact of addition of olive oil on thermal degradation of refined rapeseed oil
PublicationFats are an important component of the everyday diet and have a significant impact on the proper functioning of human organism. However, during the process of frying chemical transformations take place in the oil; hence fats characterised by high oxidative stability should be given preference. The aim of this work was to determine the quality of rapeseed oil, blended oil, and refined olive oil, all sourced from the domestic market....
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Z type Observer Backstepping For Induction Machines
PublicationThis paper contains a relatively new synthesis method for non-linear objects, named backstepping. This method can be used to obtain the observer structure. The paper presents the structure of the speed observer which is a new proposition of observer backstepping with additional state variables marked Z. The rotor speed can be estimated in three different ways. The first is based on the adaptive approach, the second on the nonadaptive...
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Degradable poly(ester-ether) urethanes of improved surface calcium deposition developed as novel biomaterials
PublicationBones, which are considered as hard tissues, work as scaffold for human body. They provide physical support for muscles and protect intestinal organs. Percentage of hard tissues in human body depends on age, weight, and gender. Human skeleton consists of 206 connected bones. Therefore, it is natural that the hard-tissue damage such as fractures, osteoporosis, and congenital lack of bone may appear. The innovative way of bone healing...
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Flame retardant epoxy/halloysite nanotubes nanocomposite coatings: Exploring low-concentration threshold for flammability compared to expandable graphite as superior fire retardant
PublicationEpoxy nanocomposites containing halloysite nanotubes (HNTs) were developed and their low-concentration thresholds for thermal stability and flame retardancy were compared with that of epoxy system containing expandable graphite (EG), as a reference with superior flame retardancy. The effects of HNTs and EG on the peak of Heat Release Rate (pHRR), Total Heat Release (THR), and Time-To-Ignition (TTI) of the prepared samples were...
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Molecular dynamics simulations reveal the balance of forces governing the formation of a guanine tetrad—a common structural unit of G-quadruplex DNA
PublicationG-quadruplexes (G4) are nucleic acid conformations of guanine-rich sequences, in which guanines are arranged in the square-planar G-tetrads, stacked on one another. G4 motifs form in vivo and are implicated in regulation of such processes as gene expression and chromosome maintenance. The structure and stability of various G4 topologies were determined experimentally; however, the driving forces for their formation are not fully...
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A. Computational analysis by molecular docking of thirty alkaloid compounds from medicinal plants as potent inhibitors of SARS-CoV-2 main protease(2020). Focused on analysis of the Medicinal plants that have potential therapeutic ability against COVID-19.
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Numerical Issues and Approximated Models for the Diagnosis of Transmission Pipelines
PublicationThe chapter concerns numerical issues encountered when the pipeline flow process is modeled as a discrete-time state-space model. In particular, issues related to computational complexity and computability are discussed, i.e., simulation feasibility which is connected to the notions of singularity and stability of the model. These properties are critical if a diagnostic system is based on a discrete mathematical model of the flow...
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Correlation between natural frequencies and buckling load in a stiffened shell
PublicationThe paper deals with correlation between natural frequencies and buckling load of a stiffened shell composed of corrugated sheets and vertical stiffeners (columns). The simplified shell segment represents the buckling behaviour of a whole silo with sparsely distributed columns. The paper covers variants of linear buckling anal-yses, dynamic eigenvalue analyses and geometrically non-linear analyses of a segment modelled with shell...
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A robust sliding mode observer for non-linear uncertain biochemical systems
PublicationA problem of state estimation for a certain class of non-linear uncertain systems has been addressed in this paper. In particular, a sliding mode observer has been derived to produce robust and stable estimates of the state variables. The stability and robustness of the proposed sliding mode observer have been investigated under parametric and unstructured uncertainty in the system dynamics. In order to ensure an unambiguous non-linear...
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Estimation of zero buoyancy of the batyscaphe. Pneumatic buoyancy control of the bathyscaphe
PublicationThe subjects of this work are matters concerning the batyscaphe designed and constructed by the Scientific Circle of Young Constructors (SCoYC) acting at the Faculty of Technical Sciences of the Olsztyn University of Warmia and Mazury.The goal od the remote-controlled batyscaphe is an underwater exploration of water resorvoirs in Poland. Design and construction of the unmanned watercraft, also known as a batyscaphe, required the...
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Preparation and Characterization of Indomethacin Supramolecular Systems with β-Cyclodextrin in Order to Estimate Photostability Improvement
PublicationCyclodextrins have found wide application in contemporary chemistry, pharmacy andmedicine. Because of their unique properties, cyclodextrins are constantly used in research on solubility or stability improvement, as well as other physicochemical properties of medicinal substances. Indomethacin (IND) is a photolabile molecule that also attracts the interest of researchers due to its therapeutic potential and the need to...
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Equivalent Single Layer Models in Free Vibration Analysis of Laminated Multi-Layered Plates
PublicationThe performance of selected equivalent single-layer (ESL) models is evaluated within several classical benchmark tests for small amplitude free vibration analysis of multi-layered plates. The authors elaborated their own Finite Element software based on the first-order shear deformation (FOSD) theory with some modifications incorporated including a correction of the transverse shear stiffness and an application of zigzag type functions....
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Smart Email - Almost an Agent Platform
PublicationNetwork organizations suffer today of information overload and strain that rise their operational costs. One of the reasons of that is the dominance of email messaging as the princi-pal means of document exchange between their workers. Proac-tive documents can rationalize these costs and augment email systems with a process view based on collaboration patterns.
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Synthesis and reactivity of O-acyl selenophosphates
PublicationThe synthesis of several new O-acyl selenophosphates were investigated. The stability and reactivity of the products were studied and related to their structure.
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Modeling and MANOVA studies on toxicity and endocrine potential of packaging materials exposed to different extraction schemes
PublicationThe stability of the linings of packaging that is in contact with the goods stored has been of major concern during decades of the development of packaging materials. In this work, an attempt was undertaken to assess the applicability of using two bioassays (Microtox® and XenoScreen YES/YAS) in estimating the stability of packaging (cans, caps, multilayer material) and the impact of their degradation on the toxicity of some simulated media....
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Mathematical analysis of a generalised p53-Mdm2 protein gene expression model
PublicationWe propose the generalisation of the p53-Mdm2 protein gene expression model introduced by Monk (2003). We investigate the stability of a unique positive steady state and formulate conditions which guarantee the occurrence of the Hopf bifurcation. We show that oscillatory behaviour can be caused not only by time lag in protein transcription process, but also can be present in the model without time delay. Moreover, we investigate...
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Rigid polyurethane foams modified with selected flame retardants
PublicationThe flame retardants: expandable graphite, triethylphosphatehas been used in rigid polyurethane foams (PUFs). The influence of fillers amounts on processing parameters, physical-mechanical properties (compression strength, density, water absorption, brittleness)and thermal properties (thermal stability) of such foams has been analyzed.The gel, cram and rise time for PUFs modified with flame retardant has been observed during synthesis...
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Experimental investigation of thermal energy storage in shell-and-multi-tube unit with nano-enhanced phase change material
PublicationThis paper deals with thermal energy storage with use of nanoparticle enhanced phase change material in shell-and-multitube unit. The experiments are conducted under atmospheric pressure. Paraffin wax and two different fatty acids are used as base phase change material. Graphite and multi-walled carbon nanotubes serve as nanoparticles. Graphite nanoparticles are tested at the concentrations of 0.1%, 1% and 5% by weight, while multi-walled...
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Security of export transactions in the offer of leading banks on the Polish market
PublicationThe following article presents the so-called conditioned payment methods, i.e. instruments for securing export transactions, such as letter of credit, documentary collection, bank guarantees, factoring and forfaiting. The characteristics of each particular method are presented as well as the transactions using them are described. In the following paper, the author included also the leading Polish banks, which offer the above- mentioned...
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One-dimensional chaos in a system with dry friction: analytical approach
PublicationWe introduce a new analytical method, which allows to find chaotic regimes in non-smooth dynamical systems. A simple mechanical system consisting of a mass and a dry friction element is considered. The corresponding mathematical model is being studied. We show that the considered dynamical system is a skew product over a piecewise smooth mapping of a segment (the so-called base map). For this base map we demonstrate existence of...
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High-Speed Binary-to-Residue Converter Design Using 2-Bit Segmentation of the Input Word
PublicationIn this paper a new approach to the design of the high-speed binary-to-residue converter is proposed that allows the attaining of high pipelining rates by eliminating memories used in modulo m generators. The converter algorithm uses segmentation of the input binary word into 2-bit segments. The use and effects of the input word segmentation for the synthesis of converters for five-bit moduli are presented. For the number represented...
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Carboxy derivative of dioxydiphenylpropane diglycydyl ether monomethacrylate as an addtive for composites
PublicationThe modifier of composites was used in the presence of polyetylene polyamine. Physico-mechanical properties and chemical stability of coatings thus obtained were analyzed.
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Light-Modulated Sunscreen Mechanism in the Retina of the Human Eye
PublicationThe functioning of the human eye in the extreme range of light intensity requires a combination of the high sensitivity of photoreceptors with their photostability. Here, we identify a regulatory mechanism based on dynamic modulation of light absorption by xanthophylls in the retina, realized by reorientation of pigment molecules induced by trans–cis photoisomerization. We explore this photochemically switchable system using chromatographic...
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Cognitum Ontorion: Knowledge Representation and Reasoning System
Publication“If knowledge can create problems, it is not through ignorance that we can solve them.” (Isaac Asimov). Nevertheless, at any point of human activity, knowledge (besides practice) is a key factor in understanding and solving any given problem. Nowadays, computer systems have the ability to support their users in an efficient and reliable way. In this paper we present and describe the functionality of the Cognitum Ontorion system....
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Determination of organophosphorus and organonitrogen pesticides in water samples
PublicationPesticides are among the most dangerous environmental pollutants because of their stability, mobility and long-term effects on living organisms. Their presence in sources of drinking water, essential to life, is a particular danger. In water, these compounds can undergo transformations, leading to the production of substances of even greater toxicity. Legal regulations are in force, stipulating the highest permissible level of...
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Influence of Ionic Liquid Structure on Supported Ionic Liquid Membranes Effectiveness in Carbon Dioxide/Methane Separation
PublicationThis paper indicates the possibility of application of imidazolium ionic liquids immobilized in polymeric supports—supported ionic liquid membranes—in CO2 separation from gaseous streams (e.g., biogas). Imidazolium salts containing alkyl fluoride anions, bis(trifluoromethylsulfonyl)imide and trifluoromethanesulfonate, selectively separating CO2 were used. The permeability of CO2 through membranes was investigated under gas pressure...
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DMSO and TMAO—Differences in Interactions in Aqueous Solutions of the K-Peptide
PublicationInteractions between a solvent and their co-solute molecules in solutions of peptides are crucial for their stability and structure. The K-peptide is a synthetic fragment of a larger hen egg white lysozyme protein that is believed to be able to aggregate into amyloid structures. In this study, a complex experimental and theoretical approach is applied to study systems comprising the peptide, water, and two co-solutes: trimethylamide...
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Functional Components Enhancing Clients Attractiveness and Commercial Profitability of Internet Tourist-oriented Commercial Websites
PublicationTourism constitutes an important branch of economy in Mediterranean countries. Great number of people spend or are planning to spend their free time in the Mediterranean area. Extensive rentals of private apartments or houses for individual persons and their families as well as all kinds of services provided for tourists, in result, generate substantial economical incomes. Variety and diversity of offers of private accommodations...
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Toward mechanosynthesis of diamondoid structures: V. Silicon as the material of choice for preliminary implementation of intermediate generation of nano-machine systems
PublicationStosując ostatnio wprowadzony przez Drexlera ''moduł skalowany stałą sieciową'' KLM, porównano dwa potencjalne nano-materiały, krzem i diament. Szczegółowe porównanie właściwości fizycznych i chemicznych wykazuje, że krzem może być rozważany jako materiał z wyboru dla pierwotnej implementacji pośredniej generacji nano-systemów.
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Kompozytowy most pieszo-rowerowy w kampusie Politechniki Gdańskiej – badania doświadczalne
PublicationW artykule przedstawiono wybrane badania doświadczalne kompozytowej kładki dla pieszych. Badaniu poddano zarówno segment walidacyjny będący wycinkiem pełnowymiarowe konstrukcji, jak również dźwigar o docelowej długości. Wykonano badania w zakresie obciążeń statycznych, jak również identyfikację parametrów dynamicznych z zastosowaniem testu wzbudzenia impulsowego.