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Determinants of the Internationalization of Family Firms - a Structural Eqquation Modeling Analysis
PublicationCurrently, international behaviors of family businesses (FBs) attract a growing interest of researchers. In an increasingly competitive environment, numerous FBs are forced to expand into foreign markets in search for ways to survive or grow. The article is both theoretical and empirical. In the theoretical part it presents theoretical concepts of FBs internationalization, especially determinants for their going international....
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Multi-objective antenna design by means of sequential domain patching
PublicationA simple yet robust methodology for rapid multiobjective design optimization of antenna structures has been presented. The key component of our approach is sequential domain patching of the design space which is a stencil-based search that aims at creating a path that connects the extreme Pareto-optimal designs, obtained by means of single-objective optimization runs. The patching process yields the initial approximation of the...
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Information Retrieval with the Use of Music Clustering by Directions Algorithm
PublicationThis paper introduces the Music Clustering by Directions (MCBD) algorithm. The algorithm is designed to support users of query by humming systems in formulating queries. This kind of systems makes it possible to retrieve songs and tunes on the basis of a melody recorded by the user. The Music Clustering by Directions algorithm is a kind of an interactive query expansion method. On the basis of query, the algorithm provides suggestions...
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Phenotypic consequences of LYS4 gene disruption in Candida albicans
PublicationA BLAST search of the Candida Genome Database with the Saccharomyces cerevisiae LYS4 sequence known to encode homoaconitase (HA) revealed ORFs 19.3846 and 19.11327. Both alleles of the LYS4 gene were sequentially disrupted in Candida albicans BWP17 cells using PCR-based methodology. The null lys4Δ mutant exhibited lysine auxotrophy in minimal medium but was able to grow in the presence of L-Lys and α-aminoadipate, an intermediate...
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Beta-Galactosidases of Pseudoalteromonas sp. – Characteristics and application for lactose hydrolysis and galactopyranosides synthesis
PublicationBeta-galactosidase [EC 3.2.1.23] is an enzyme that catalyzes the hydrolysis of O-glycosidic linkages in galactosides. It has biotechnological applications in the dairy industry for the production of milk with a low content of lactose and galactooligosacharides for use in healthy food. The transgalactosylation activity of beta-galactosidase can be used in the synthesis of alkyl galactopyranosides. Due to the fact that conditions of...
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Discovering relationships between data in an enterprise information system using log analysis
PublicationEnterprise systems are inherently complex and maintaining their full, up-to-date overview poses a serious challenge to the enterprise architects’ teams. This problem encourages the search for automated means of discovering knowledge about such systems. An important aspect of this knowledge is understanding the data that are processed by applications and their relationships. In our previous work, we used application logs of an enterprise...
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Pyrolysis Combined with the Dry Reforming of Waste Plastics as a Potential Method for Resource Recovery—A Review of Process Parameters and Catalysts
Publication: Emissions of greenhouse gases and growing amounts of waste plastic are serious environmental threats that need urgent attention. The current methods dedicated to waste plastic recycling are still insufficient and it is necessary to search for new technologies for waste plastic management. The pyrolysis-catalytic dry reforming (PCDR) of waste plastic is a promising pro-environmental way employed for the reduction of both CO2 and...
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A sense of security and freedom in a residential environment
PublicationThe article is based on the results of a survey carried out among students of architecture faculties in several countries, which examined the students’ knowledge of shaping the housing environment in such a way as to enable them to fulfil two basic and, at the same time, seemingly mutually exclusive psychological needs of a person: a sense of security and a sense of freedom. In examining these issues, particular emphasis was placed...
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Delivery of Ancillary Services in Distribution Power Systems
PublicationOne of the technical and organizational challenges the power system faces in deregulated market conditions is to organize an ancillary services market. The growing share of distributed generation of variable (intermittent) energy sources and a change in the market position of consumers, causes the demand for distributed delivery of ancillary services. For this purpose, it is sought to use the ability of the regulatory measures:...
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Low-fidelity model considerations for simulation-based optimisation of miniaturised wideband antennas
PublicationHere, variable-fidelity electromagnetic (EM)-based design optimisation of miniaturised antennas is discussed. The authors focus on an appropriate selection of discretisation density of the low-fidelity EM model, which results in good performance of the optimisation algorithm in terms of its computational complexity and reliability. Trust-region gradient search with low-fidelity model corrected by means of non-linear frequency scaling...
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Extracting concepts from the software requirements specification using natural language processing
PublicationExtracting concepts from the software require¬ments is one of the first step on the way to automating the software development process. This task is difficult due to the ambiguity of the natural language used to express the requirements specification. The methods used so far consist mainly of statistical analysis of words and matching expressions with a specific ontology of the domain in which the planned software will be applicable....
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On low-fidelity models for variable-fidelity simulation-driven design optimization of compact wideband antennas
PublicationThe paper addresses simulation-driven design optimization of compact antennas involving variable-fidelity electromagnetic (EM) simulation models. Comprehensive investigations are carried out concerning selection of the coarse model discretization density. The effects of the low-fidelity model setup on the reliability and computational complexity of the optimization process are determined using a benchmark set of three ultra-wideband...
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Diethyl carbonate as a green extraction solvent for chlorophenol determination with dispersive liquid–liquid microextraction
PublicationThe principles of green analytical chemistry indicate that the search for greener organic solvents for extraction applications is crucial. In this study diethyl carbonate (DEC) is proved to be a green solvent, as it is relatively nontoxic, obtainable from renewable resources and biodegradable. Here it is applied as an extraction solvent for chlorophenol determination in water samples with dispersive liquid–liquid microextraction....
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LSA Is not Dead: Improving Results of Domain-Specific Information Retrieval System Using Stack Overflow Questions Tags
PublicationThe paper presents the approach to using tags from Stack Overflow questions as a data source in the process of building domain-specific unsupervised term embeddings. Using a huge dataset of Stack Overflow posts, our solution employs the LSA algorithm to learn latent representations of information technology terms. The paper also presents the Teamy.ai system, currently developed by Scalac company, which serves as a platform that...
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Development and tuning of irregular divide-and-conquer applications in DAMPVM/DAC
PublicationThis work presents implementations and tuning experiences with parallel irregular applications developed using the object oriented framework DAM-PVM/DAC. It is implemented on top of DAMPVM and provides automatic partitioning of irregular divide-and-conquer (DAC) applications at runtime and dynamic mapping to processors taking into account their speeds and even loads by other user processes. New implementations of parallel applications...
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Identification of regions of interest in video for a traffic monitoring system
PublicationA system for automatic event detection in the camera image is presented in this paper. A method of limiting a region of interest to relevant parts of the image using a set of processing procedures is proposed. Image processing includes object detection with shadow removal performed in the modified YCbCr color space instead of RGB. The proposed procedures help to reduce the complexity of image processing algorithm and result in...
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Human voice modification using instantaneous complex frequency
PublicationThe paper presents the possibilities of changing human voice by modifying instantaneous complex frequency (ICF) of the speech signal. The proposed method provides a flexible way of altering voice without the necessity of finding fundamental frequency and formants' positions or detecting voiced and unvoiced fragments of speech. The algorithm is simple and fast. Apart from ICF it uses signal factorization into two factors: one fully...
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Robustified estimators of radar elevation angle using a specular multipath model
PublicationWe consider the problem of estimating the elevation angle in the presence of multipath. The proposed method belongs to the class of maximum likelihood-like estimators and employs a modified specular reflection model that accounts for the uncertainty of the steering vector by assuming that they are subject to unknown deterministic perturbations with bounded norms. The analysis, performed using convex optimization methods, allows...
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Fabrication and structural properties of Y and Fe co-doped SrTiO3 nanoceramics for SOFC
PublicationYttria and iron co-doped strontium titanate perovskites, (Y0,07Sr0,93Ti1-xFexO3-δx=0,1; 0,2) samples were fabricated by two methods: solid-state synthesis (SS) and the Pechinisol-gel modified method. The morphology of samples were measured by SEM and X-raydiffraction. Results were compared and discussed. The strong relationship between fabricationprocedure and microstructure has been proven. It was also observed, that the nanoceramicsobtained...
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Hybrid biobateryy based on arylated carbon nanotubes and laccase
PublicationSingle-walled carbon nanotubes (SWCNT) were covalently modified with antracene and antraquinone and used for the construction of cathodes for biocatalytic reduction od dioxygen. The nanotubes with aromatic groups casted onto the electrode increased the working surface of the electrode and enabled efficient direct electron tarnsfer (DET) between the enzyme and the electrode. the aryl groups enter the hydrophobic pocket of the T1...
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Evaluation of solid phase extraction for downstream separation of propane-1,3-diol and butan-1-ol from fermentation broth
PublicationGlycerol is mainly a by-product of fat splitting and biodiesel production. This study examined the use of chemically modified silica gels for downstream separation of propane-1,3-diol and butan-1-ol from fermentation broths obtained through the glycerol fermentation process. The developed method was found to be simple and efficient for the isolation and purification of butan-1-ol from the other components in the fermentation mixture....
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Influence of Flat Lapping Kinematics on Machinability of Ceramics
PublicationNew tools for flat grinding of ceramics are presented in the paper. Electroplated CBN tools (B64 and B107) were used in a modified single-disc lapping machine configuration. The results from experiments, such as the material removal rate and surface roughness parameters are presented and analyzed. Numerical simulations, based on the model for the shape error and tool wear estimation in machining with flat lapping kinematics, are...
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Materials for Mediator-free Electron Transfer in the Enzymatic Electrodes of Biobatteries and Biofuel Cells
PublicationWe present functionalization of single-walled carbon nanotubes (SWCNTs) and their application in the enzymatic fuel cells construction. SWCNTs were covalently modified with different types of aromatic moieties. Free radical reaction was employed to create direct carbon-carbon bond between moiety and SWCNTs. In second approach functionalization takes place through amide bonding. Functionalized SWCNTs were characterized by spectroscopy...
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Path Loss Modelling in the Untypical Outdoor Propagation Environments
PublicationIn the paper three ways of path loss modelling in the untypical outdoor environments are presented. The exemplary untypical outdoor environment is analyzed. The investigated environment is characterized, and the measurement campaign are shortly described. The following models have been analyzed: the COST231 Walfisch-Ikegami model, the modified COST231Walfisch-Ikegami model tuned on the basis of empirical data, and the empirical...
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Four Level Diode-Clamped Back-To-Back Converter with Active DC Link Voltage Control
PublicationThis article presents the design and control of 4L-DC back-to-back converter. To solve the DC link voltage balancing problem in four-level converter a new three-level double chopper topology based on PO-PWM modulation was designed and successfully tested. Also, the paper describes two phase space vector pulse width modulation 2P-SVPWM based on the shape function of finite elements. The control structure with modified Dead-Beat...
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Nanosize effect of clay mineral nanoparticles on the drug diffusion processes in polyurethane nanocomposite hydrogels
PublicationStudies of swelling and release of naproxen sodium (NAP) solution by polyurethane nanocomposite hydrogels containing Cloisite® 30B (organically modified montmorillonite (OMMT)) have been performed. Polyurethane nanocomposite hydrogels are hybrid, nontoxic biomaterials with unique swelling and release properties in comparison with unmodified hydrogels. These features enable to use nanocomposite hydrogels as a modern wound dressing....
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Synthesis and modification of reduced graphene oxide aerogels for biofuel cell applications
PublicationWe have carried out the preparation of reduced graphene oxide aerogels using eco-friendly method that is based on the Hummers method of graphite oxidation without the use of NaNO3 that produces toxic gases. To obtain a porous 3D structure of reduced graphene oxide, we performed the hydrothermal reduction at elevated temperature. We also prepared the rGO aerogel/CNT composite using multiwalled carbon nanotubes as linkers. The rGO...
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DATA INTEROPERABILITY AND THE OPEN DATA ECOSYSTEM: ROLES AND RESEARCH AREAS
PublicationSustainability and value-creation are considered important parameters to measure the success of an open data system. Unfortunately, existing open data systems are not meeting their promises to achieve a sustainable and value-based open data system. Van Loenen et al. (2021) proposed a sustainable and value-creating open data ecosystem. According to their study, the open data ecosystem needs to be user-driven, inclusive, circular,...
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The searchlight problem for road networks
PublicationWe consider the problem of searching for a mobile intruder hiding in a road network given as the union of two or more lines, or two or more line segments, in the plane. Some of the intersections of the road network are occupied by stationary guards equipped with a number of searchlights, each of which can emit a single ray of light in any direction along the lines (or line segments) it is on. The goal is to detect the intruder,...
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Analiza i ocena poprawności działania węzła tarcia w aspekcie II zasady termodynamiki
PublicationW artykule przedstawiono autorską metodę sprawdzania poprawności działania węzła tarcia traktowanego jako układ tribologiczny w aspekcie II zasady termo-dynamiki na podstawie analizy i oceny wyników badań laboratoryjnych wykonanych na stanowisku badawczym. Jako stanowisko wykorzystany został zmodyfikowany węzeł tarcia aparatu czterokulowego T-02. Zaprezentowano algorytm, według którego zostały wykonane badania empiryczne. Wykazano,...
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Generalized adaptive notch filters with frequency debiasing for tracking of polynomial phase systems
PublicationGeneralized adaptive notch filters are used for identification/tracking of quasi-periodically varying dynamic systems and can be considered an extension, to the system case, of classical adaptive notch filters. For general patterns of frequency variation the generalized adaptive notch filtering algorithms yield biased frequency estimates. We show that when system frequencies change slowly in a smooth way, the estimation bias can...
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Enhancement of the Brayton cycle efficiency by water or steam utilization
PublicationIn the paper, thermodynamic analysis of two modifications of a Brayton cycle into enhancement cycles with water/steam injection are discussed. The first one deals with a STIG modified system with both interstage compressed air cooling and air heating (heat regeneration) before combustion chamber. The second one, mainly devoted to higher steam/air ratio, is connected with separate steam production in a HRSG. The analysis has been...
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Non-proportional full-order Luenberger observers of induction motors
PublicationThe paper recapitulates recently conducted investigations of non-proportional Luenberger observers, applied to reconstruction of state variables of induction motors. Three structures of non-proportional observers are analyzed, a proportional-integral observer, modified integral observer and observer with integrators. Criteria for gain selection of the observer are described, classical ones based on poles, as well as additional,...
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Application of algorithms for reasoning from imperfect knowledge in it evaluation environment
PublicationThe paper describes concept of building multi-agent system dedicated for information technology evaluation or selection for IT enterprises management (IT_MAS). Authors present the model of Knowledge Processing Environment, which is one of main components of the solution. Either facts or rules will be based on IT specialists' experience. However, knowledge which is being acquisited from IT domain is mostly imperfect - uncertain...
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Recent breakthroughs in the stability testing of pharmaceutical compounds
PublicationPharmaceutical development is mostly focused on the research leading to approval of a new and viable active substance. However, there is a number of old generation compounds that are still being used in contemporary medicinal practice. So that new analytical developments should cover not only the safety of newly developed drug substances, which is obvious, but should also be directed into the search of individual stability issues...
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Remote Monitoring of Environmental Pollutants
PublicationAtmospheric air quality is one of the key factors influencing human health. Air quality evaluation is not an easy task as the atmosphere is a complex system subjected to continuous changes in time. Observed progress in the development of measurement devices and technologies is fundamental for acquisition of more reliable information about condition and quality of atmospheric air. Unfortunately, this process leads to an increase...
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Design of dimensionally stable composites using efficient global optimization method
PublicationDimensionally stable material design is an important issue for space structures such as space laser communication systems, telescopes, and satellites. Suitably designed composite materials for this purpose can meet the functional and structural requirements. In this paper, it is aimed to design the dimensionally stable laminated composites by using efficient global optimization method. For this purpose, the composite plate optimization...
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The Ellenbogen's "Matter as Software" Concept for Quantum Computer Implementation: III. Selection of X@C60 Molecular Building Blocks (MBBs) for Tip-Based Nanofabrication (TBN) of Trapped Neutral Atom Quantum Computing Devices
PublicationThe selection of guest atoms X of X@C60 MBBs for TBN of trapped neutral atom quantum computing devices is reported. Assuming the all-optical quantum computing as a final target stage, the two criteria are most important: the charge q accumulated on the C60 host must be as low as possible, and the atom X must have one or more available excited states within the band falling into the low energy window of neutral C60 molecule electronic...
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Synthesis and biological evaluation of novel analogues of batracylin with synthetic amino acids and adenosine: an unexpected effect on centromere segregation in tumor cells through a dual inhibition of topoisomerase IIa and Aurora B
PublicationIn the search for new anticancer agents we designed and synthesized batracylin derivatives with linking synthetic amino acid side chains of different lengths and adenosine. Unexpectedly, we have found that in water and the culture media adenosine–amino acid–BAT conjugates form supramolecular structures and this prevents these compounds from entering cells. Consequently, these compounds exerted no biological activity when tested...
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Theory vs. practice. Searching for a path of practical education
PublicationThe introduction of a three-tier model of higher education (the Bologna model) has led to considerable changes in the 1st- and 2nd-tier technical courses at universities. At present, a student with a bachelor’s degree can be employed in his / her profession after completing only 7 semesters of study. A search is under way for methods of combining theoretical knowledge taught at universities with practical knowledge gained afterwards....
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Reliable low-cost surrogate modeling and design optimisation of antennas using implicit space mapping with substrate segmentation
PublicationAbstract: In this work, a reliable methodology for fast simulation-driven design optimisation of antenna structures is proposed. The authors’ approach exploits implicit space mapping (ISM) technology. To adopt it for handling antenna structures, they introduce substrate segmentation with separate dielectric permittivity value assigned for each segment as ISM preassigned parameters. At the same time, the coarse model for space mapping...
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Rapid design closure of linear microstrip antenna array apertures using response features
PublicationA simple yet reliable approach to a rapid design closure of linear antenna array apertures at the electromagnetic (EM)-simulation level is proposed. Our methodology exploits an underlying array factor (AF) model suitably corrected by means of characteristic points (angles and levels) of the radiation pattern of the EM model of the antenna array aperture. This conveniently allows for controlling both the side lobe levels...
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THE USE OF MORPHOLOGICAL FILTERS AND GRANULOMETRIC METHOD TO ANALYZE THE MOVEMENT OF THE MOLECULES IN THE SEA WATER OF THE SOUTHERN BALTIC SEA
PublicationModern granulometry opens a new way of analysing images by means of morphological filters. In this paper a closer look has been presented on the problem of interpreting information about the features and conditions of marine environment from images taken at the sea coast and shallow water. Using this method allows for example selection of the objects on the image according to the differences in shape. Processes occurring in the...
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On the Limiting Distribution of Lempel-Ziv’78 Redundancy for Memoryless Sources
PublicationWe study the Lempel-Ziv'78 algorithm and show that its (normalized) redundancy rate tends to a Gaussian distribution for memoryless sources. We accomplish it by extending findings from our 1995 paper, in particular, by presenting a new simplified proof of the central limit theorem (CLT) for the number of phrases in the LZ'78 algorithm. We first analyze the asymptotic behavior of the total path length in the associated digital search...
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Are creative users more apt in reusing and adopting Open Government Data (OGD)? Gender differences
PublicationOpen Government Data (OGD) has been considered as a potent instrument for value creation and innovation by a range of stakeholders. Given that individual ingenuity is a function of individual and environmental factors, it is important to understand how the OGD adoption and usage is a factor of creative performance behaviors (CPB), viz., Problem Identification (PI), Information Search (IS), Idea Generation (IG) and Idea Promotion...
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Computer-Aided Greenery Design—Prototype Green Structure Improving Human Health in Urban Ecosystem
PublicationIncreasing population and urbanization, with climate change consequences, such as rising temperatures, influence public health and well-being. The search to improve the quality of life in cities becomes one of the priority objectives. A solution can be found in the role of greenery in an urban environment and its impact on human health. This opens a path toward experimentation on microclimate green structures that can be inserted...
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Intelligent Audio Signal Processing − Do We Still Need Annotated Datasets?
PublicationIn this paper, intelligent audio signal processing examples are shortly described. The focus is, however, on the machine learning approach and datasets needed, especially for deep learning models. Years of intense research produced many important results in this area; however, the goal of fully intelligent signal processing, characterized by its autonomous acting, is not yet achieved. Therefore, a review of state-of-the-art concerning...
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Parallel implementation of a Sailing Assistance Application in a Cloud Environment
PublicationSailboat weather routing is a highly complex problem in terms of both the computational time and memory. The reason for this is a large search resulting in a multitude of possible routes and a variety of user preferences. Analysing all possible routes is only feasible for small sailing regions, low-resolution maps, or sailboat movements on a grid. Therefore, various heuristic approaches are often applied, which can find solutions...
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Improving SBR Performance Alongside with Cost Reduction through Optimizing Biological Processes and Dissolved Oxygen Concentration Trajectory
PublicationAuthors of this paper take under investigation the optimization of biological processes during the wastewater treatment in sequencing batch reactor (SBR) plant. A designed optimizing supervisory controller generates the dissolved oxygen (DO) trajectory for the lower level parts of the hierarchical control system. Proper adjustment of this element has an essential impact on the efficiency of the wastewater treatment process as well...
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Size-Controlled Synthesis of Pt Particles on TiO2 Surface: Physicochemical Characteristic and Photocatalytic Activity
PublicationDifferent TiO2 photocatalysts, i.e., commercial samples (ST‐01 and P25 with minority of rutile phase), nanotubes, well‐crystallized faceted particles of decahedral shape and mesoporous spheres, were used as supports for deposition of Pt nanoparticles (NPs). Size‐controlled Pt NPs embedded in TiO2 were successfully prepared by microemulsion and wet‐impregnation methods. Obtained photocatalysts were characterized using XRD, TEM,...