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Search results for: empirical potentials
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Diagnostic tolerances' evaluation method of the start-up exhaust temperature of a naval gas turbine
PublicationThe conducted investigations aimed to elaborate the method of marking diagnostic tolerances of the exhaust temperature of a gas turbine observed during engine's start-up process. The diagnostic tolerances were determined by means of statistical inference by creating the hypothesis about a normal distribution of the start-up exhaust temperature's dispersion in the initial operation moment, which was subsequently verified applying...
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Sectors in Poland - Patterns of Concentration
PublicationThe main aim of the paper presented below, is to analysefrom theoretical point of view market concentration as economicproblem. The authors come out of defining market concentration, theypresent basic concentration measures, and characterize sectors onPoland on that ground. In the empirical part, the authors haveanalysed patterns of concentration of 35 sectors in Poland in timeperiod 1997-2006. We draw on recently made available...
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Environmental Taxes and Their Role in the Economics of Sustainable Development
PublicationThe purpose of this article is to answer the question of the role of environmental taxes in the economics of sustainable development. The first part of the article discusses the idea of sustainable economic development and the economics of sustainable development. Then, environmental taxes are defined, their essence explained and their role in the economics of sustainable development discussed in theoretical terms, which finally...
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Exchange-Traded Funds in Europe
PublicationExchange-Traded Funds in Europe provides a single point of reference on a diverse set of regional ETF markets, illuminating the roles ETFs can play in risk mitigation and speculation. Combining empirical data with models and case studies, the authors use diffusion models and panel/country-specific regressions—as well as graphical and descriptive analyses— to show how ETFs are more than conventional, passive investments. With new...
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The Role of Electrostatics in Enzymes: Do Biomolecular Force Fields Reflect Protein Electric Fields?
PublicationPreorganization of large, directionally oriented, electric fields inside protein active sites has been proposed as a crucial contributor to catalytic mechanism in many enzymes, and it may be efficiently investigated at the atomistic level with molecular dynamics simulations. Here, we evaluate the ability of the AMOEBA polarizable force field, as well as the additive Amber ff14SB and Charmm C36m models, to describe the electric...
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Application of Aqueous Biphasic Systems Extraction in Various Biomolecules Separation and Purification: Advancements Brought by Quaternary Systems
PublicationAqueous biphasic systems (ABS) extraction is a simple, selective, efficient and easy to scale-up technology that, over the years, has attracted a considerable attention from the researcher community as an alternative methodology in downstream processing of a wide variety of biomolecules. This review summarizes and discusses the fundamental features of ABS, as well as its advantages and disadvantages, as a separation and purification...
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State-of-the-art ideas for engineering laboratory classes – virtual reality framework
PublicationNowadays challenges in science and technology are a driving force in the development of contemporary solutions in education. Virtual reality brings to an edge human imagination. In this paper, authors propose a framework for civil engineering laboratory classes which brings a new quality in this area. The framework shows how to provide learners with an environment where they can realize the health and safety hazards of construction...
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Knowledge Risks in the Sharing Economy
PublicationThis chapter presents a theoretical analysis of potential risks connected with knowledge that organizations operating in the sharing economy might potentially face. Nowadays, it can be stated that an increasing amount of individuals and organizations participate in sharing and exchanging data, information, and knowledge, as well as physical goods and services (Botsman & Rogers, 2011). The development of the sharing economy has...
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Hydrothermal modification of TiO2 nanotubes in water and alkali metal electrolytes (LiNO3, NaNO3, KNO3) – Direct evidence for photocatalytic activity enhancement
PublicationThe influence of hydrothermal annealing (HA) of TiO2 nanotubes (TiO2-NTs) in various baths (H2O, LiNO3, NaNO3, KNO3 performed for 4 h, 24 h, 64 h), on their photocatalytic and photoelectrocatalytic properties, was studied. The use of electrolytes was to enable the monitoring of photoactivity changes as a result of the expected impact on the population of hydroxyl groups on the surface. The assumption turned out to be correct and...
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Consciousness Study of Subjects with Unresponsive Wakefulness Syndrome Employing Multimodal Interfaces
PublicationThe paper presents a novel multimodal-based methodology for consciousness study of individuals with unresponsive wakefulness syndrome. Two interfaces were employed in the experiments: eye gaze tracking system – CyberEye developed at the Multimedia Systems Department, and EEG device with electrode placement in the international 10-20 standard. It was a pilot study for checking if it is possible to determine objective methods based...
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Comparison of single microjet cooling with water, ethanol and HFE7100 as test fluids
PublicationThe paper presents the investigation of a single microjet cooling forming an thin liquid film on the impingement surface of specially designed rig. The basis of microjet technology is to produce laminar jets, which when impinging the surface have a very high kinetic energy at the stagnation point. Applied technology of jet production can result with the size of jets ranging from 20 to 500μm in breadth and 20 to 100μm in width....
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CHALLENGES TO NATIONAL ECONOMIES OF SELECTED EU COUNTRIES IN THE CONTEXT OF DEMOGRAPHIC CHANGES IN SOCIETY
PublicationThe countries of Central and Eastern Europe, which acceded to the EU in 2004, are facing a great challenge related to transformations in the level and demographic structure of the population. The observed adverse demographic developments require taking decisive actions aimed at curbing the negative trend. The purpose of this paper is to present changes in the level and demographic structure of population and their impact on...
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An improved method for flow boiling heat transfer with account of the reduced pressure effect
PublicationIn the paper are presented the results using the authors own model to predict heat transfer coefficient during flow boiling. The model has been tested against a large selection of experimental data to investigate the sensitivity of the in-house developed model. In the work are presented the results of calculations obtained using the semi-empirical model on selected experimental flow boiling data of the refrigerants: R134a, R1234yf,...
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The Impact of Trade Integration with the European Union on Productivity in a Posttransition Economy: The Case of Polish Manufacturing Sectors
PublicationThis paper addresses the relationship between productivity growth in Polish manufacturing sectors and forces stemming from trade integration with the European Union. Empirical analysis (1995-2006) is based on sector-level bilateral data concerning both domestic (Polish) and foreign (partner countries from the enlarged European Union) markets' characteristics and their degree of openness. The main results indicate that, both in...
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A newly-developed model for predicting cutting power during wood sawing with circular saw blades
PublicationIn the classical approach, cutting forces and cutting power in sawing processes of orthotropic materials such as wood are generally calculated on the basis of the specific cutting resistance kc (cutting force per unit area of cut). For every type of sawing kinematics (frame saws, band saws and circular sawing machines) different empirical values of specific cutting resistance kc have to be applied. It should be emphasised that...
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A pilot study to assess an in-process inspection method for small diameter holes produced by Direct Metal Laser Sintering
PublicationPurpose The purpose of this research is to evaluate the geometric quality of small diameter holes in parts printed by DMLS technology. An in-process optical inspection method is proposed and assessed during a pilot study. The influence of the theoretical hole diameter assumed in a CAD system and the sample thickness (hole length) on the hole clearance was analysed. Design/methodology/approach The samples made of two different...
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Modelowanie bezpiecznika rozłącznikowego w układach formowania impulsów wielkiej mocy
PublicationProblem modelowania bezpieczników o dużej dynamice wyłączania prądu jest zagadnieniem szeroko opisywanym w literaturze. Układy takie mogą być wykorzystane w szczególności do formowania impulsów wysokiego napięcia o wartościach rzędu setek kV, charakteryzujących się czasem trwania rzędu ułamka μs. W niniejszej pracy przedstawiono empiryczny model bezpiecznika wielotopikowego, rozszerzony w oparciu o wyniki badań eksperymentalnych.
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Correlation–polarization effects in electron/positron scattering from acetylene: A comparison of computational models
PublicationDifferent computational methods are employed to evaluate elastic (rotationally summed) integral and differential cross sections for low energy (below about 10 eV) positron scattering off gas-phase C2H2 molecules. The computations are carried out at the static and static-plus-polarization levels for describing the interaction forces and the correlation–polarization contributions are found to be an essential component for the correct...
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Ionosphere variability II: Advances in theory and modeling
PublicationThis paper aims to provide an overview on recent advances in ionospheric modeling capabilities, with the emphasis in the efforts relevant to electron density variability. The discussion spans a wide range of model formulations (e.g., from purely empirical to physics-based ones and data-driven approaches) seeking for advances or gaps with regard to present challenges. This discussion is further supported by consideration of the...
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The differential impact of a density of Polish pine wood on cutting forces with its origin region taken into consideration
PublicationIn the article the dependence of cutting forces in a function the density of wood with regard to the wood origin are presented. Samples used in experiment were with Scotch pine (Pinus sylvestris L.) originating from four provenances in Poland (Figure 1). Wood density was measured by two methods: stereometric method (global density) and radiometric method (local density). Stereometric method consists in measurements the volume...
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Simulation of parallel similarity measure computations for large data sets
PublicationThe paper presents our approach to implementation of similarity measure for big data analysis in a parallel environment. We describe the algorithm for parallelisation of the computations. We provide results from a real MPI application for computations of similarity measures as well as results achieved with our simulation software. The simulation environment allows us to model parallel systems of various sizes with various components...
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Fracture mechanics model of cutting power versus widespread regression equations while wood sawing with circular saw blades
PublicationA comparison of the theoretical cutting power consumption results forecasted with the model (FM_CM model) which include work of separation (fracture toughness) in addition to plasticity and friction, and two widespread regression equations while wood sawing with circular saw blades has been described. in and cutting power consumption forecasted. In computations of the cutting power consumption during rip sawing of Scots pine wood...
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THE SITUATION OF WOMEN IN THE POLISH LABOUR MARKET IN THE LIGHT OF CHANGES IN THE PENSION SECURITY SYSTEM
PublicationThe aim of the study is to examine the opinion of a group of women on their economic activity and decisions related to retirement. The first part of the article reviews previous research related to the economic activity of older people with a special focus on women. In the empirical part of the article, women’s opinions on issues related to retirement were analyzed. The research was carried out in 2016 on a sample of 45 women,...
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ICT-driven economic and financial development. Analyses of European countries
PublicationICT-Driven Economic and Financial Development: Analyses of European Countries demonstrates the effects of ICT diffusion on economic, social and financial development by examining their impact on the structure and dynamics of national economies. It provides the insight into shifts observed in labour markets, international trade activities productivity factors, education and use of innovative financial products. It combines empirical...
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Antecedents and Consequences of Brand Loyalty
PublicationThe objective of this paper is to review, systematize, and summarize empirical research on the antecedents and consequences of brand loyalty. The literature review has identified five categories of antecedents to brand loyalty associated with consumer, brand, social, corporate and relational factors. The type of loyalty formed varies according to the combination of various antecedents, with premium loyalty being considered the...
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Towards Knowledge Sharing Oriented Adaptive Control
PublicationIn this paper, we propose a knowledge sharing oriented approach to enable a robot to reuse other robots' knowledge by adapting itself to the inverse dynamics model of the knowledge-sharing robot. The purpose of this work is to remove the heavy fine-tuning procedure required before using a new robot for a task via reusing other robots' knowledge. We use the Neural Knowledge DNA (NK-DNA) to help robots gain empirical knowledge and...
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The optimization of CuxO microwires synthesis for improvement in photoelectrochemical performance
PublicationOne of the most important challenges in the fabrication of CuxO microstructures via the electrochemical method is formation of long, regular and well-packed microwires with good adhesion on the Cu substrate and to achieve better photoelectrochemical properties, which can be potentially applied in solar-driven water splitting and CO2 conversion to light hydrocarbons. In this paper, Cu2O photoelectrode has been fabricated by direct...
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Friction and Lubrication of Large Tilting-Pad Thrust Bearings
PublicationFluid film bearings have been extensively used in the industry because of their unbeatable durability and extremely low friction coefficient, despite a very low coefficient of friction dissipation of energy being noticeable, especially in large bearings. Lubricating systems of large tilting pad thrust bearings utilized in large, vertical shaft hydrogenerators are presented in this paper. A large amount of heat is generated due...
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Some Security Features of Selected IoT Platforms
PublicationIoT (Internet of Things) is certainly one of the leading current and future trends for processing in the current distributed world. It is changing our life and society. IoT allows new ubiquitous applications and processing, but, on the other hand, it introduces potentially serious security threats. Nowadays researchers in IoT areas should, without a doubt, consider and focus on security aspects. This paper is aimed at a high-level...
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Knowledge risks in organizations – Insights from companies
PublicationPurpose: Knowledge risks are increasingly becoming a great challenge to a variety of organizations. At the same time, academic research on such types of risks, their consequences, and potential ways of overcoming them is still scarce and fragmented. To fill this gap, the paper aims to find out do companies manage their knowledge risks, what are the possible knowledge risks they face and have they observed an increase of knowledge...
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Hybrid quantum-classical approach for atomistic simulation of metallic systems
PublicationThe learn-on-the-fly (LOTF) method [G. Csanyi et al., Phys. Rev. Lett. 93, 175503 (2004)] serves to seamlessly embed quantum-mechanical computations within a molecular-dynamics framework by continual local retuning of the potential's parameters so that it reproduces the quantum-mechanical forces. In its current formulation, it is suitable for systems where the interaction is short-ranged, such as covalently bonded semiconductors....
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Executing Multiple Simulations in the MERPSYS Environment
PublicationThe chapter investigates the steps necessary to perform a simulation instance in the MERPSYS environment and discusses potential limitations in case when vast numbers of simulations are required. An extended architecture is proposed which includes a JMS-based simulation queue and multiple distributed simulators, overcoming the potential bottlenecks. The chapter introduces also methods for preparing suites of multiple simulations...
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Property revenues (PRs) and expenditures of local government units (LGUs) in Poland
PublicationPRs are new category of local government revenues, which was introduced by changing the law on public finances at the end of 2006 and which took effect in 2007. By principle, these revenues should be converted into property expenditures. Their formalisation did not only allow assessing their absolute size but also a comparison with the longer existing property expenditures. Both categories were subject of analysis in this article....
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Tradycyjna versus przyspieszona internacjonalizacja przedsiębiorstw z branż high-tech. Wyniki badań empirycznych
PublicationThe discussion on the role and importance of time in the process of internationalization of firms belongs to the mainstream of research in the field of internationalization. In the literature, the phenomenon of early and rapid internationalization was noticed in the early 1980s; however, the intensive development of the research into this phenomenon began a decade later and continues today. For several years in Poland, the share...
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Fading Analysis in Off-Body Channels in a Straight Metallic Corridor in a Passenger Ferry Environment
PublicationThis paper presents a fading analysis for Body Area Networks off-body communications at 2.45 GHz in a passenger ferry environment. The results are based on measurements performed for dynamic scenarios in a straight metallic corridor. Two components, extracted from instantaneous system loss values, have been analysed: small- and large-scales fading, separately for each scenario. Well-known probability distribution functions have...
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Employees 55+ - valuable resource in SMEs
PublicationThe article relates to the problem of exploiting the potential of workers aged 55 years or more to build the competitiveness of the SME sector. The aim of the study was an attempt to formulate an answer to the question whether entrepreneurs and managers are able to identify the potential of older workers and whether they use this potential to build the competitiveness of their enterprises. The article is based on the results of...
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Rozumienie cechą inteligentnego przedsiębiotstwa
PublicationW artykule podniesiono istotę pojęcia ‘rozumienie’ w aspekcie inteligentnego przedsiębiorstwa. Przeprowadzone badania teoretyczne i empiryczne pozwoliły na wyłonienie rozumienia wewnętrznego i zewnętrznego. Rozumienie wewnętrzne w inteligentnym przedsiębiorstwie dotyczy sfer: pracowników oraz całego przedsię-biorstwa. Natomiast rozumienie zewnętrzne skierowane jest na otoczenie i potrze-bę dostosowania przedsiębiorstwa.
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Krótko- i długookresowe skorygowane krańcowe skłonności do konsumpcji. Gospodarka Polski w latach 1995-2018
PublicationWe wstępnej części artykułu - odwołując się do teorii Keynesa - omówiono i zdefiniowano podstawowe relacje makroekonomiczne pomiędzy konsumpcją globalną a produktem krajowym brutto. W następnej kolejności przeprowadzono analizę informacji statystycznych dotyczących prywatnych wydatków konsumpcyjnych gospodarstw domowych (C) oraz globalnych wydatków konsumpcyjnych społeczeństwa (CO) na tle produktu krajowego brutto (PKB) w Polsce...
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Structure of liquid gold from tight-binding driven molecular-dynamics
PublicationPraca przedstawia wyniki symulacji ciekłego złota w nadkomórce periodycznej przy użyciu stworzonego przez autorów programu komputerowego, za pomocą połączonych metod dynamiki molekularnej (MD) i ciasnego wiązania (TB). Omówiono strukturę tak symulowanej cieczy, porównując ją z dostępnymi danymi doświadczalnymi oraz wynikami innych symulacji, pod kątem radialnej i kątowej funkcji rozkładu i elektronowej gęstości stanów.A tight-binding...
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The “autumn effect” in the gold market—does it contradict the Adaptive Market Hypothesis?
PublicationThe present study aims to verify the autumn effect in the gold market, first presented 10 years ago by Dirk Baur in the paper “The autumn effect of gold” and to investigate the calendar effects occurring for other precious metals. This empirical research is presented in a way to place the results obtained in the context of the Efficient Market Hypothesis (EMH) and the more current Adaptive Market Hypothesis (AMH). The study was...
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Artificial intelligence and productivity: global evidence from AI patent and bibliometric data
PublicationIn this paper we analyse the relationship between technological innovation in the artificial intelligence (AI) domain and macroeconomic productivity. We embed recently released data on patents and publications related to AI in an augmented model of productivity growth, which we estimate for the OECD countries and compare to an extended sample including non-OECD countries. Our estimates provide evidence in favour of the modern productivity...
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Effects of social media communication on brand equity and brand purchase intention
PublicationThe author studied the effect of two different social media communication on brand equity and brand purchase intention. A total of 504 data sets were generated through a standardized online-survey and analysed with structural equation modeling. The results of the empirical study showed that both firm-created and user-generated social media communication influenced brand equity, consequently impacting brand purchase intention. This...
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Developing Game-Structure Sensitive Matchmaking System for Massive-Multiplayer Online Games
PublicationProviding a fair matchmaking system is an essential issue, while developing every online video game. In the article, we show that the currently existing matchmaking system in League of Legends, one of the most popular online video games currently existing, is built on a base of conditions which do not hold true in the presence of empirical data. This, in short, decreases the effectiveness of the ranking system, and negatively affects...
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How Specific Can We Be with k-NN Classifier?
PublicationThis paper discusses the possibility of designing a two stage classifier for large-scale hierarchical and multilabel text classification task, that will be a compromise between two common approaches to this task. First of it is called big-bang, where there is only one classifier that aims to do all the job at once. Top-down approach is the second popular option, in which at each node of categories’ hierarchy, there is a flat classifier...
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Export diversification and economic development: a dynamic spatial data analysis
PublicationThis 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...
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Structural design and sensitivity analysis of semi-rigid pavement of a motorway
PublicationThis paper presents application of mechanistic-empirical methods in design of semi-rigid pavement for a section of a motorway in Poland. The stage construction was assumed. Three fatigue criteria were applied in the design. For asphalt fatigue cracking and subgrade soil the criteria from the Asphalt Institute (USA) were applied. For fatigue cracking of cement stabilized bases the Dempsey (USA) and De Beer (South Africa) criteria...
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Fading Modelling in Dynamic Off-Body Channels
PublicationThis paper presents an off-body fading channel model for Body Area Networks. The proposed model, based on both simulations and measurements at 2.45 GHz in a realistic indoor environment, consists of three components: mean path loss, body shadowing, and multipath fading. The first is modelled as a log function of distance, the path loss exponent being in between 0.4 and 1.6. A statistical perspective is taken for the other two components,...
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Accuracy Analysis of Determination the Vertical Displacements in Unstable Reference System
PublicationMeasurements of horizontal and vertical displacements are carried out mostly based on reference points identified as fixed. In surveying practice there may be some situations in which there is not possible to perform the measurements with reference to stable points or the difficulties in identification of points’ stability may arise. Accuracy analysis based on the covariance matrices have a special role in this process. In presented...
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VARIANT DESIGNING IN the PRELIMINARY SMALL SHIP DESIGN PROCESS
PublicationShip designing is a complex process, as the ship itself is a complex, technical multi-level object which operates in the air/water boundary environment and is exposed to the action of many different external and internal factors resulting from the adopted technical solutions, type of operation, and environmental conditions. A traditional ship design process consists of a series of subsequent multistage iterations, which gradually...
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Does the low optical band gap of yellow Bi3YO6 guarantee the photocatalytical activity under visible light illumination?
PublicationBi3YO6, which is known as an ionic conductor, was tested here as an electrode and photoanode in contact with aqueous electrolytes. Bi3YO6 was deposited onto the Pt substrate and the such prepared electrode was polarized in various aqueous electrolytes. The optical energy band gap of the material equal to 1.89 eV was determined using the Kubelka-Munk function resulting from the UV-Vis spectrum (allowed indirect transition) and also...