Search results for: HS-SPME/GCXGC-TOFMS - Bridge of Knowledge

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Search results for: HS-SPME/GCXGC-TOFMS

Search results for: HS-SPME/GCXGC-TOFMS

  • Determination of volatile organic compounds using solventless sample preparation techniques and gas chromatography

    Publication

    - Year 2012

    In this paper the latest advances in the determination of volatile organic compounds using solvent-free extraction techniques in the sample preparation step are presented. A paper is focus mainly on one of the most popular sample preparation technique: solid-phase microextraction technique (SPME) combined with different detection systems and its applications to sampling of VOCs from the samples with different matrices. This paper...

  • Wykorzystanie techniki mikroekstrakcji do fazy stacjonarnej w analityce środowiskowej.**2002, 122 s. 25 rys. 31 tab. bibliogr. 465 poz. maszyn. Rozprawa doktorska /10.12.2002/ Wydz. Chem. PG Promotor: prof. dr hab. inż. Jacek Namieśnik

    Publication
    • A. Jastrzębska

    - Year 2002

    Przeprowadzone badania obejmowały: opracowanie podstaw metodycznych oznacza-nia lotnych amin alifatycznych w powietrzu za pomocą GC ze wzbogacaniem te-chniką SPME; określenie warunków oraz parametrów pracy urządzenia do SPME wwarunkach badań modelowych; zbadanie wpływu temperatury, wilgotności i stę-żenia gazowej mieszaniny wzorcowej na efektywność procesu wzbogacania anali-tów z wykorzystaniem urządzenia do SPME; porównanie...

  • Ireneusz Kreja dr hab. inż.

    Graduated from the mathematical class at the Nicolaus Copernicus High School in Gdańsk (1974). Master of Sciences in Civil Engineering after studies at Gdansk University of Technology (GUT), Poland (1974-1979). Since 1979 became an employee of the GUT. In 1989 earned a Ph.D. degree in Civil Engineering (with grade "Summa cum Laude") from the GUT. In 2008 obtained a D. Sc. (Habilitation) degree in Civil Engineering (with grade...

  • Comparing phylogenetic trees using a minimum weight perfect matching

    Publication

    - Year 2008

    A phylogenetic tree represents historical evolutionary relationshipbetween different species or organisms. There are various methods for reconstructing phylogenetic trees.Applying those techniques usually results in different treesfor the same input data. An important problem is to determinehow distant two trees reconstructed in such a wayare from each other. Comparing phylogenetic trees is alsouseful in mining phylogenetic information...

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  • A novel method of time-frequency analysis: an essential spectrogram

    Publication

    A novel precise method of time-frequency analysis is presented. In the algorithm, a new energy distribution is estimated by simultaneously discard or displacement of the classical spec- trogram energy. A channelized instantaneous frequency and a local group delay are used in order to replacement in the same manner as formulated by Kodera et al. [1, 2]. Additionally, new representations: a channelized instantaneous bandwidth and...

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  • Low-energy positron scattering from gas-phase uracil

    Publication

    - EUROPEAN PHYSICAL JOURNAL D - Year 2014

    Quantum scattering calculations are presented for the interaction of low energy positrons with the uracil molecule, an important component of biological systems. The rotational elastic and inelastic cross sections and vibrational inelastic cross sections are reported and compared with existing experiments, indicating a general trend of the cross sections different from the experimental findings and in line with what should be expected...

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  • Modeling DAC Application Execution Time

    Publication

    - Year 2016

    An application written in the Divide And Conquer paradigm is more difficult to model than SPMD application because of complex algorithm, causing use of many coefficients in a computational complexity function. Processors are divided into various layers, each layer contains different number of processors. Data packets processed in different layers and transferred between layers have different length. Moreover first layer processors use...

  • Mass spectrometric identification of 13C-Labeled metaboloites during anaerobic propanoic acid oxidation

    Publication
    • M. Felchner-Zwirello
    • J. Winter
    • C. Gallert

    - CHEMISTRY & BIODIVERSITY - Year 2012

    Biowaste digestion is a possibility to gain biogas as a renewable fuel source. However, the anaerobic food chain may be disrupted by, e.g., substrate overload or by inhibitors, leading to the accumulation of volatile fatty acids (VFAs), predominantly of propanoic acid (PA). VFA Accumulation may cause a rapid pH decrease, less biogas production, or even a total inhibition. To maintain high biogas productivity or to prevent a collapse...

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  • Mass Spectrometric Identification of 13C-Labeled Metabolites DuringAnaerobic Propanoic Acid Oxidation

    Publication
    • M. Felchner-Zwirello
    • J. Winter
    • C. Gallert

    - CHEMISTRY & BIODIVERSITY - Year 2012

    Biowaste digestion is a possibility to gain biogas as a renewable fuel source. However, the anaerobic food chain may be disrupted by, e.g., substrate overload or by inhibitors, leading to the accumulation of volatile fatty acids (VFAs), predominantly of propanoic acid (PA). VFA Accumulation may cause a rapid pH decrease, less biogas production, or even a total inhibition. To maintain high biogas productivity or to prevent a collapse...

  • Próba oceny efektów projektowania układów geometrycznych toru z wykorzystaniem komercyjnych programów komputerowych

    Publication

    - Year 2015

    W pracy podjęto kwestię dokładności uzyskiwanej w projektowaniu układów geometrycznych toru z wykorzystaniem komercyjnych programów komputerowych typu CAD. Opisano w sposób ogólny funkcjonowanie wybranego programu. Do celów weryfikacji wykorzystano własną, analityczną metodę projektowania układów torowych. W analizie porównawczej rzędnych poziomych rozpatrzono trzy warianty układu geometrycznego zawierającego łuk koszowy z trzema...

  • state aid for projects on heritage conservation

    Open Research Data
    open access

    The dataset encompassed a choice of the most important legal acts in EU law, a list of selected bibliography, together with a list of some interesting individual EC decisions issued on the topic of state aid for heritage conservation in Poland and some UE countries in the period 2007-2013. The reader gets the possibility to acquire basic information...

  • Kamila Kokot-Kanikuła mgr

    Kamila Kokot-Kanikuła is a digital media senior librarian at Gdańsk University of Technology (GUT) Library. She works in Digital Archive and Multimedia Creation Department and her main areas of interests include early printed books, digital libraries, Open Access and Open Science. In the Pomeranian Digital Library (PDL) Project she is responsible for creating annual digital plans, transferring files on digital platform, and promoting...

  • Average Size of a Suffix Tree for Markov Sources

    Publication

    - Year 2016

    We study a suffix tree built from a sequence generated by a Markovian source. Such sources are more realistic probabilistic models for text generation, data compression, molecular applications, and so forth. We prove that the average size of such a suffix tree is asymptotically equivalent to the average size of a trie built over n independentsequences from the same Markovian source. This equivalenceis only known for memoryless...

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  • Proof of Concept of Indoor Location System Using Long RFID Readers and Passive Tags

    Publication

    The paper proposes a system for persons and objects location with the use of long radio-frequency identifications (RFIDs) readers. In order to investigate all aspects of the proposed location system, several key elements had to be analyzed, including the distance from which the tagged objects and the possibility of using more than one tag within one RFID range at the same time. When designing the system, it is also necessary to...

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  • Green Chemistry - current and future issues

    Publication

    W pracy przedstawiono 12 zasad Zielonej Chemii oraz wybrane przykłady stosowania zasad w życiu codziennym, przemyśle, laboratoriach i edukacji. Pokrótce opisano historię Zielonej Chemii oraz przyszłe wyzwania. ZCH dotyczy nowego podejścia do zagadnienia syntezy, przeróbki i wykorzystania związków chemicznych, związanego ze zmniejszeniem zagrożenia dla zdrowia i środowiska. Istnieje wiele publikacji opisujących metodyki analityczne...

  • Oznaczanie niezmienionych form lotnych związków bromo- i chloroorganicznych w próbkach płynów biologicznych z wykorzystaniem opracowanej metodyki TLHS-DAI-GC-ECD

    Publication

    - Year 2005

    Rozprawa doktorska dotyczyła opracowania nowej procedury analitycznej opartej na wykorzystaniu analizy fazy nadpowierzchniowej nad cienkim filmem cieczy z samoczynną generacją strumienia ciekłego sorbentu w połączeniu z chromatografem gazowym wyposażonym w detektor wychwytu elektronów (TLHS-DAI-GC-ECD). Skupiono się na :1. wykonaniu badań optymalizacyjnych poprzedzających walidację metodyki TLHS-DAI-GC-ECD (sprawdzenie trwałości...

  • Experimental and theoretical investigation of conformational states and noncovalent interactions in crystalline sulfonamides with a methoxyphenyl moiety

    Publication

    - CRYSTENGCOMM - Year 2021

    Four sulfonamide derivatives with a methoxyphenyl moiety, namely N-{4-[(2-methoxyphenyl)sulfamoyl] phenyl}acetamide (1a), N-{4-[(3-methoxyphenyl)sulfamoyl]phenyl}acetamide (1b), 4-amino-N-(2- methoxyphenyl)benzenesulfonamide (2a) and 4-amino-N-(3-methoxyphenyl)benzenesulfonamide (2b), have been synthesized and characterized physiochemically by CHNS, MS, FT-IR, 1H NMR, 13C NMR, PXRD and TG methods. Crystal structures were determined...

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  • Mass Spectrometric Identification of 13C-labeled Metabolites During anaerobic Propanoic Acid Oxidation

    Publication

    - CHEMISTRY & BIODIVERSITY - Year 2012

    Biowaste digestion is a possibility to gain biogas as a renewable fuel source. However, the anaerobic food chain may be disrupted by, e.g., substrate overload or by inhibitors, leading to the accumulation of volatile fatty acids (VFAs), predominantly of propanoic acid (PA). VFA Accumulation may cause a rapid pH decrease, less biogas production, or even a total inhibition. To maintain high biogas productivity or to prevent a collapse...

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  • Corporate Governance and Ownership Structure in the Top 30 Listed Non Financial Companies in Poland

    Publication

    - Year 2014

    This paper offers a first analysis of the relationships between corporate governance models and rules and ownership structure of the top 30 Polish firms listed at the WSE (not considering foreign firms and/or the Polish branches of foreign firms listed at the same stock exchange, nor the financial companies and the banks). The general picture depicted by this analysis is putting into evidence the increasing importance of institutional...

  • Identification of diagnostic parameter sensitivity during dynamic processes of a marine engine

    Publication

    - Combustion Engines - Year 2015

    Changing some parameters of the engine structure alters the emission of harmful components in the exhaust gas. This applies in particular to the damage of charge exchange system as well as fuel system and engine supercharger. These changes are much greater during the dynamic states and their accompanying transitional processes. The different sensitivity of diagnostic parameters to the same force, coming from the engine structure, but...

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  • The Hybrid Fuzzy - SOEKS Approach to the Polish Internet Mortgage Market

    The paper presents the hybrid fuzzy- SOEKS approach to the Polish Internet mortgage market, which is treated as an example of a fast changing market. Firstly, the market and market problems are described. Then, the first approach to the market problems is presented: the complete fuzzy model which was built basing on the rules. The fuzzy model is presented on one real data case. Next, the new approach, called Set of Experience Knowledge...

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  • Iwona Kochańska dr hab. inż.

    Iwona Kochańska is a graduate of Faculty of Electronics, Telecommunications and Informatics, Gdansk University of Technology. She received M.Sc. degree in Automation Control and Robotics, specializing in the mobile objects control. In 2012 she received Ph.D. degree in hydroacoustics. In the same year she started working as an assistant professor in the Department of Marine Electronic Systems. The main area of interest is hydroacoustis, ...

  • Affective computing and affective learning – methods, tools and prospects

    Every teacher knows that interest, active participation and motivation are important factors in the learning process. At the same time e-learning environments almost always address only the cognitive aspects of education. This paper provides a brief review of methods used for affect recognition, representation and processing as well as investigates how these methods may be used to address affective aspect of e-education. The paper...

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  • On the correlation between magnetoacoustic emission and magnetostriction dependence on the applied magnetic field

    The correlation between magnetoacoustic emission signal envelopes and magnetostriction curves is investigated. Two sets of samples are being considered: tempered martensitic steel and plastically deformed ferritic steel. It is shown that even though some general relations may be observed, as was demonstrated in the literature, the correlation is not always present. One may not expect to change both quantities in the same way if...

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  • Can we rely on the pulse transit time - pressure relationship - models comparison

    Publication

    An unobtrusive, noninvasive and continuous pressure measurement is invaluable however, still being under research and development. There are many attempts proposing an appropriate relationship between pulse pressure velocity and pressure. Fifteen different formulas, both theoretical and experimental, describing relation between blood pressure and crosssectional area of the vessel were examined. Using these formulas the relation...

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  • The estimation of total volatile organic compounds emissions generated from peroxide cured natural rubber/polycaprolactone blends

    Natural rubber (NR)/polycaprolactone (PCL) blends at the ratio of 90/10% wt. (NR/PCL90/10) and 70/30% wt. (NR/PCL70/30), with a constant amount of dicumyl peroxide, were prepared by compounding in an internal mixer. Obtained NR/PCL bio-based blends were cured at three different temperatures (150 °C, 160 °C and 170 °C). The total content of volatile organic compounds (TVOC) as a function of the NR/PCL blends ratio, and their curing...

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  • Synthesis and photoelectrochemical behaviour of hydrogenated titania nanotubes modified with conducting polymer infiltrated by redox active network

    In this work, we show preparation of ordered inorganic-organic composite electrode material where hydrogenated titania nanotubes H-TiO2 with tubularly developed surface modified with poly(3,4-ethylenedioxythiophene) matrix permeated by Prussian Blue (PB) inorganic redox network in order to reach highly photoactive heterojunction. The polymer deposition was realized via two subsequent processes covering: i) potentiostatic polymerization...

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  • FEM modelling of screw displacement pile interaction with subsoil

    Predicting the-settlement characteristics of piles is an important element in the designing of pile foundations. The most reliable method in evaluating pile-soil interaction is the static load test, preferably performed with instrumentation for measuring shaft and pile base resistances. This, however, is a mostly post-implementation test. In the design phase, prediction methods are needed, in which numerical simulations play an...

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  • Zagospodarowanie ciepła odpadowego z biogazowych agregatów kogeneracyjnych w oczyszczalni ścieków = Waste heat utilisation from cogeneration set in sewage plant

    Publication

    W pracy opisano koncepcję współpracy biogazowych modułów kogeneracyjnych z niskotemperaturowym obiegiem parowym. Proponowana modernizacja pozwoliłaby na wykorzystanie entalpii fizycznej spalin, tym samym zwiększając sprawność urządzeń wytwarzających ciepło i energię elektryczną. Tego typu rozwiązanie umożliwiłoby częściowe pokrycie zapotrzebowania własnego na energię elektryczną, generując oszczędności w przedsiębiorstwie. W artykule...

  • Zagospodarowanie ciepła odpadowego z biogazowych agregatów kogeneracyjnych w oczyszczalni ścieków

    Publication

    W pracy opisano koncepcję współpracy biogazowych modułów kogeneracyjnych z niskotemperaturowym obiegiem parowym. Proponowana modernizacja pozwoliłaby na wykorzystanie entalpii fizycznej spalin, tym samym zwiększając sprawność urządzeń wytwarzających ciepło i energię elektryczną. Tego typu rozwiązanie umożliwiłoby częściowe pokrycie zapotrzebowania własnego na energię elektryczną, generując oszczędności w przedsiębiorstwie. W artykule...

  • Shape-Memory Polyurethane Polymers

    Publication

    - ACS SYMPOSIUM SERIES - Year 2021

    Polyurethanes (PUs) are one of the most widely used polymers in research and industry. They can be synthesized from chemical sources and natural sources. PUs are a very useful class of polymers and exhibit many desirable properties that can be exploited in various applications. PUs are formed by the reaction between polyols and isocyanates. A wide variety of polyols and isocyanates are available for synthesis, and hence we can...

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  • Membrane Solid Phase Microextraction - a new concept of sorbent preparation

    Opracowano nowy układ sorpcyjny do izolacji i/lub wzbogacania polarnych analitów organicznych z próbek wody z zastosowaniem techniki solid phase microextraction (SPME). Układ bazuje na oddzieleniu sorbentu polarnego od próbki za pomocą membrany hydrofobowej. Próbnik membrane-SPME (M-SPME) sporządzono z zastosowaniem polietylenoglikolu (PEG)o masie cząsteczkowej 20 kDa. Polimer ten jest rozpuszczalny w wodzie i w typowych warunkach...

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  • Jacek Namieśnik prof. dr hab. inż.

    People

    Scientific discipline: chemistryRector in 2016-2019 He was born on 10 December, 1949 in Mogilno. He graduated in 1972 at the Faculty of Chemistry at Gdańsk University of Technology, obtaining a master's degree in chemical engineering. In 1972 he started working at Gdańsk University of Technology, where in 1978 he defended his doctoral thesis and in 1985 he completed his habilitation. He was appointed an associate professor in 1991...

  • Marek Biziuk prof. dr hab. inż.

    People

    CURRICULUM VITAE Marek BIZIUK  Born                                        1947 MSc                                         1969 GUT PhD                                         1977 GUT DSc                                         1994 GUT Professor                                 2001   Membership of scientific society - Gdansk Scientific Society - Romanian Society of Analytical Chemistry - Engineers and Techniques of...

  • Weak forms of shadowing in topological dynamics

    Publication

    We consider continuous maps of compact metric spaces. It is proved that every pseudotrajectory with sufficiently small errors contains a subsequence of positive density that is point-wise close to a subsequence of an exact trajectory with the same indices. Also, we study homeomor- phisms such that any pseudotrajectory can be shadowed by a finite number of exact orbits. In terms of numerical methods this property (we call it multishadowing)...

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  • Entrepreneurship nests in a polish edge city

    Publication

    - Year 2020

    The last two decades in Poland have been a period of both a dynamic development of the small and medium-sized enterprise sector and a transformation of the city surrounding territories. This development began during the economy transformation after 1989. Population migration and movement of economic entities away from central cities resulted in development of territorial structures within some Polish suburban areas, defined as...

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  • Silica-Based Ionogels: Nanoconfined Ionic Liquid-Rich Fibers for Headspace Solid-Phase Microextraction Coupled with Gas Chromatography–Barrier Discharge Ionization Detection

    Publication

    In this work, hybrid silica-based materials with immobilized ionic liquids (ILs) were prepared by sol–gel technology and evaluated as solid-phase microextraction (SPME) fiber coatings. High loadings of the IL 1-methyl-3-butylimidazolium bis(trifluoromethylsulfonyl)imide ([C4MIM][TFSI]) were confined within the hybrid network. Coatings composition and morphology were evaluated using scanning electron microscopy and energy dispersive...

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  • EU state aid within the Rural Development Program 2014-2020

    Open Research Data
    open access

    This dataset is a combination of EU and Polish legislation on the state aid in the agriculture sector, selected literature and few exemples of European Commission decisions on projects initiated in some EC Member States during the budgetary period 2014-2020. Careful reading of the materials will allow to review some effects of the state aid granted...

  • Heat transfer intensification by enlarged surface roughness in the plate heat exchanger

    Publication

    - Year 2013

    In the paper an experimental analysis of passive heat transfer intensification technique employed in the case of the plate heat exchanger is presented. The passive intensification was obtained by a modification of the heat transfer surface. The roughness of surface was increased by a use of glass micro-beads. Single-phase convective heat transfer in the water-water system was studied. The experiment was accomplished in two stages....

  • Comparison of pavement noise properties on selected road sections using different CPX measuring systems: self-powered vehicle and special test trailer

    Publication

    - Year 2019

    The recently published ISO standard intended to measure the noise properties of road surfaces in a standardized method (ISO 11819-2:2017) precisely defines measurement procedure of the influence of road surface on traffic noise. According to it, two types of test vehicles may be utilized: a self-powered vehicle fitted with one or more test tyres and a trailer towed by a separate vehicle with one or more test tyres mounted on the...

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  • The EU Tyre Noise Label: The problem with measuring the noise level of only a few of all tyre variants

    Publication

    - Year 2022

    The STEER project, described in another Inter-Noise 2022 paper, has evaluated the performance of the noise label of the European tyre label. The major finding was that uncertainties of the tyre/road noise measurements were higher than should be accepted. One of the worst uncertainty sources was found to be the common practice to measure only some tyres of all sizes or variants within a tyre line, to save money. Generally, only...

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  • Automatic sound source localization in disturbing conditions using acoustic vector sensors

    A concept, practical realization and applications of a passive acoustic radar to automatic localization and tracking of sound sources in disturbing conditions were presented in the paper. The device consists of the new kind of multichannel miniature sound intensity sensors and a group of digital signal processing algorithms. The sensitivity of the realized acoustic radar was examined in free sound field. Several kinds of sound...

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  • Aerodynamic shape optimization by variable-fidelity computational fluid dynamics models: a review of recent progress

    Publication

    - Journal of Computational Science - Year 2015

    A brief review of some recent variable-fidelity aerodynamic shape optimization methods is presented.We discuss three techniques that—by exploiting information embedded in low-fidelity computationalfluid dynamics (CFD) models—are able to yield a satisfactory design at a low computational cost, usu-ally corresponding to a few evaluations of the original, high-fidelity CFD model to be optimized. Thespecific techniques considered here...

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  • Relativity of arithmetic as a fundamental symmetry of physics

    Arithmetic operations can be defined in various ways, even if one assumes commutativity and associativity of addition and multiplication, and distributivity of multiplication with respect to addition. In consequence, whenever one encounters ‘plus’ or ‘times’ one has certain freedom of interpreting this operation. This leads to some freedom in definitions of derivatives, integrals and, thus, practically all equations occurring in...

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  • Entangled Histories vs. the Two-State-Vector Formalism - Towards a Better Understanding of Quantum Temporal Correlations

    Publication

    The Two-State-Vector formalism and the Entangled Histories formalism are attempts to betterunderstand quantum correlations in time. Both formalisms share some similarities, but they are notidentical, having subtle differences in their interpretation and manipulation of quantum temporalstructures. However, the main objective of this paper is to prove that, with appropriately definedscalar products, both formalisms can be...

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  • Shaping the New Vistula Spit Channel: Political, Economic, and Environmental Aspects

    Publication

    In September 2022, the new shipping channel in Poland was opened for service. It connects the Port of Elbląg and the Gdańsk Bay in Poland, cutting through the Vistula Spit and the Vistula Lagoon. It was intended to enable direct access to the Baltic Sea from the Port of Elbląg without crossing Russian territory. Originally conceptualized decades ago, it has taken its final shape only recently. Its construction was associated with...

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  • Łukasz Bugalski dr inż. arch.

    Łukasz Bugalski graduated as an architect and urban planner (2013) and held a Ph.D. (2013-2018) in the same discipline (Gdańsk University of Technology). He has been Marie Skłodowska-Curie Fellow (2017-2020) trained in the critical heritage studies as part of the "CHEurope" project (MSCA Innovative Training Network) conducted at Istituto per i Beni Artistici, Culturali e Naturali della Regione Emilia-Romagna in Bologna. Currently...

  • Best Agers Lighthouses Best AgersLighthouses– Strategic Age Management for SME in the Baltic Sea Region

    Projects

    Project manager: dr inż. Anita Richert-Kaźmierska   Financial Program Name: Europejska Wspólnota Terytorialna

    Project realized in Faculty of Management and Economics according to #107 agreement from 2013-04-22

  • On adaptive covariance and spectrum estimation of locally stationary multivariate processes

    Publication

    - AUTOMATICA - Year 2017

    When estimating the correlation/spectral structure of a locally stationary process, one has to make two important decisions. First, one should choose the so-called estimation bandwidth, inversely proportional to the effective width of the local analysis window, in the way that complies with the degree of signal nonstationarity. Too small bandwidth may result in an excessive estimation bias, while too large bandwidth may cause excessive...

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  • Revising Entrepreneurial Orientation Construct in Social Enterprise

    Publication

    - Year 2017

    Entrepreneurial behavior and entrepreneurial orientation (EO) have received significant scholarly attention in entrepreneurship and management research, but mainly in the commercial context. However, some attempts discussing such behavior and EO among non-profit organizations, but limited in the social enterprise context. The literature argues that EO is higher in such contexts (Zahra, Gedajlovic, Neubaum & Shulman, 2009; Lumpkin,...

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