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Impact of Cyclist Facility Availability at Work on the Number of Bike Commuters
PublikacjaThe article describes the results of research designed to establish whether cycle provision can influence the number of employees commuting by bike. To that end, employee surveys were conducted in three IT companies in 2012 and 2016. The questionnaire asked about travel behaviour and what the staff thought about their company’s provision of cyclist facilities. Since 2012 each of the companies has moved its head office and the...
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Positive Management of Universities: A Model of Motivation to Strive for Scientific Excellence
PublikacjaObjective: The aim of the article is to conceptualise a model of work motivation in the management of universities striving for scientific excellence. Research Design & Methods: The most relevant for our aim is the self-determina tion theory that is applied to the work and organisational domain. We used a nar rative literature review. Findings: The proposed model is derived from the self-determination theory. It includes three...
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Development of cooperation in localized cooperation networks: A comparative study of cluster organizations and technology parks
PublikacjaThe main aim of the paper is to analyze the level of development of cooperative relationships in localized cooperation networks – among enterprises associated in cluster organizations and park tenants. The author reports the findings from the quantitative study carried out in the selected cluster organizations and technology parks functioning in Poland. The basic method of data collection was a survey questionnaire. The research...
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Entrepreneurial intentions of students from Latvia, Poland, and Ukraine: The role of perceived entrepreneurial education results
PublikacjaOur main aim is to establish which factors influence entrepreneurial intentions, with a particular focus on the role of entrepreneurial education and university support in Central and Eastern European countries (CEE). To verify hypotheses quantitative research was conducted using surveys among 2,085 first-year undergraduate students from three technical universities in three countries: Latvia, Poland and Ukraine. The results of...
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To meet or to connect? Face-to-face contacts vs ICT in cluster organisations
PublikacjaThe main purpose of the paper is to explore how cluster organisations (COs) take advantage of direct (F2F) and indirect (ICT) contacts in fulfilling their main roles. The paper addresses the research question: “How important are Information and Communication Technologies at each level of advancement of cluster cooperation?” The research was conducted in 2016 in four purposefully selected cluster organisations representing metal...
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Stress–strain model of lower corroded steel plates of normal strength for fitness-for-purpose analyses
PublikacjaThis study investigates the mechanical properties of specimens made of normal strength steel subjected to lower marine immersed corrosion degradation levels (below 25 %). The specimens were corroded in laboratory conditions, and only natural factors were controlled to raise the corrosion rate (reaching the level of 1 mm/year). Three different thicknesses of plates made of normal strength of shipbuilding steel are investigated (between...
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Methodology for assessing the lighting of pedestrian crossings based on light intensity parameters
PublikacjaOne of the possible preventive measures that could improve safety at crossings is to assess the state of illumination of the lighting installation located in the transition area for pedestrians. The City of Warsaw has undertaken to comprehensively assess the pedestrian crossings to determine the level of road safety and the condition of lighting. The lighting conditions related to pedestrian crossings without traffic lights in...
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Modular power converter topologies for energy storage and electric power distribution systems
PublikacjaThis paper describes selected issues concerning realization of energy storage system (ESS) designed to operate in power distribution system. In order to achieve scalability of the system a modular approach is proposed. In addition to this different configuration of the system are analyzed, where depending on requirements and application a scalability in power, in energy capacity of energy storage resource and both in power and...
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Strain-dependent behaviour of cold recycled material mixtures in cyclic compression tests
PublikacjaThe purpose of the study is to evaluate strain-dependent behaviour of Cold Recycled Material (CRM) mixtures using three frameworks typically applied for Hot Mix Asphalt (HMA): linear viscoelastic (LVE) limits; non-linearity directions; changes in rheological model parameters. To this aim, the complex modulus of three CRM mixtures with different bitumen-to-cement ratio (0.2, 0.6 and 1.8) was measured in cyclic compression mode,...
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Aerodynamic shape optimization by variable-fidelity computational fluid dynamics models: a review of recent progress
PublikacjaA 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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Estymacja napięcia niezrównoważenia w obwodzie pośredniczącym trójpoziomowego falownika NPC z wykorzystaniem obserwatora EKF
PublikacjaW artykule przedstawiono nowy algorytm estymacji napięcia niezrównoważenia w obwodzie pośredniczącym falownika 3L-NPC (ang. Three Level Neutral Diode-Clamped Converter) wykorzystujący rozszerzony filtr Kalmana. Algorytm może być wykorzystany do sterowania falownikiem bez czujnika napięcia w punkcie środkowym jak również może służyć do celów diagnostycznych czujnika polegających na porównaniu mierzonej wartości z estymowaną. W artykule...
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Pompownie dużej mocy z falownikiem wędrującym średniego napięcia
PublikacjaArtykuł zawiera rys rozwoju napędów przekształtnikowych w stacjach pomp, w szczególności regulacji wydatku kilku pomp, po kolei, przez jeden przemiennik częstotliwości. Omówiono podstawy teoretyczne zjawiska pola niestłumionego i napięcia resztkowego silników, które utrudniają szybkie przełączania silnika pompy pomiędzy zasilaniem regulowanym przez falownik a zasilaniem z sieci. Przedstawiono zasady transferu (przełączania) synchronicznego...
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Study of microstress state of P91 steel using complementary mechanical Barkhausen, magnetoacoustic emission, and X-ray diffraction techniques
PublikacjaThe paper deals with assessment of microstress state of martensite P91 steel using three complementary techniques: mechanical Barkhausen emission, magnetoacoustic emission (MAE), and X-ray diffraction (XRD) profile analysis. Magnetic coercivity Hc and microstructure were investigated with inductive magnetometry and magnetic force microscopy (MFM), respectively. Internal stress level of P91 steel was modified by heat treatment....
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Incorporating Iris, Fingerprint and Face Biometric for Fraud Prevention in e-Passports Using Fuzzy Vault
PublikacjaA unified frame work which provides a higher security level to e-passports is proposed. This framework integrates face, iris and fingerprint images. It involves three layers of security: the first layer maps a biometric image to another biometric image which is called biostego image. Three mapping schemes are proposed: the first scheme maps single biometric image to single biostego image, the second scheme maps dual biometric images...
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Pounding between high-rise buildings with different structural arrangements
PublikacjaEarthquake-induced structural pounding has led to significant damages during previous earthquakes. This paper investigates the effect of pounding on the dynamic response of colliding high-rise buildings with different structural arrangements. Three 3-D buildings are considered in the study, including 5-storey building, 7-storey building and 9-storey building. Three pounding scenarios are also taken into account, i.e. pounding between...
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Team Roles and Team Performance in Small Virtual Software Teams
PublikacjaThe article presents the results of research on the composition of team roles conducted in 24 student software teams. An adaptation of M. Belbin’s model by B. Kożusznik was used. The model of team balance according to Belbin and Haaf is presented and correlations between team balance and team performance are analysed. Team performance is measured at three levels: result, satisfaction and team climate. The selected constellation...
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Pedestrian safety management using the risk-based approach
PublikacjaThe paper presents a concept of a multi-level pedestrian safety management system. Three management levels are distinguished: strategic, tactical and operational. The basis for the proposed approach to pedestrian safety management is a risk-based method. In the approach the elements of behavioural and systemic theories were used, allowing for the development of a formalised and repeatable procedure integrating the phases of risk...
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New Tetragonal ReGa5(M) (M = Sn, Pb, Bi) Single Crystals Grown from Delicate Electrons Changing
PublikacjaSingle crystals of the new Ga-rich phases ReGa~5(Sn), ReGa~5(Pb) and ReGa~5(Bi) were successfully obtained from the flux method. The new tetragonal phases crystallize in the space group P4/mnc (No. 128) with vertex-sharing capped Re2@Ga14 oblong chains. Vacancies were discovered on the Ga4 and Ga5 sites, which can be understood as the direct inclusion of elemental Sn, Pb and Bi into the structure. Heat capacity measurements were...
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Reliable computationally-efficient behavioral modeling of microwave passives using deep learning surrogates in confined domains
PublikacjaThe importance of surrogate modeling techniques has been steadily growing over the recent years in high-frequency electronics, including microwave engineering. Fast metamodels are employed to speedup design processes, especially those conducted at the level of full-wave electromagnetic (EM) simulations. The surrogates enable massive system evaluations at nearly EM accuracy and negligible costs, which is invaluable in parameter...
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Why are trees still such a major hazard to drivers in Poland?
PublikacjaRoadside trees are one of Poland's most serious road safety issues. Since 2009 more than 2800 people have been killed as a result of tree collisions; this represents about 15% of all of Poland's accident fatalities between 2009 and 2013. In some of the country's regions striking a tree caused more than 30% of all road accident fatalities. With no proper regulations, guidelines or examples of good practice, roadside environments...
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Structural Heterogeneity Between EU15 and 12 New EU Members – the Obstacle to Lisbon Strategy Implementation
PublikacjaThe aim of this article is to identify diversity between the EU-15 and the New Members in their implementation of the Lisbon Strategy in the period 2000-2010. By analyzing a set of structural indicators, we aim to fill a gap in the literature: a lack of publications providing complex evaluation of the implementation of the Lisbon Strategy using measurable indicators. Given their suitability for international comparisons, we use...
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Elliptical slot UWB monopole antenna
PublikacjaThe UWB monopole antenna with elliptical radiating slot end and microstrip feeding line terminated with radial stub have been designed, fabricated and measured. The antenna show return loss less than -12 dB in the whole UWB bandwidth. Linearity of the reflection coefficient phase product have also been achieved. Radiation patterns of the antenna measured at three selected frequency points indicated regular, approximately omni directional...
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Local structural and chemical ordering of nanosized Pt(3±δ)Co probed by multiple-scattering x-ray absorption spectroscopy
PublikacjaThis work reports a detailed investigation of the local structure and chemical disorder of a Pt(3±δ)Co thin film and Pt(3±δ)Co nanoparticles. We have used a combination of techniques including x-ray absorption spectroscopy (XAS), x-ray diffraction (XRD), and high-resolution transmission electron microscopy (TEM). The important effect of chemical ordering on pair and three-atom configurations has been studied using computer simulations...
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IDENTIFICATION OF ODOR OF VOLATILE ORGANIC COMPOUNDS USING CLASSICAL SENSORY ANALYSIS AND ELECTRONIC NOSE TECHNIQUE
PublikacjaThe paper compares two methods of analysis of odour of volatile organic compounds: classical sensory analysis and electronic nose technique. Eight volunteers participated in the classical sensory analysis investigations, which lasted two weeks. An instrumental odour analysis involved a prototype of 6-sensor electronic nose designed by the authors. The research performed with this device provided higher reproducibility and reliability...
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Strength analysis of container ship subjected to torsional loading
PublikacjaThe objective of this work is to investigate the torsional response of a container ship, with particular consideration of the warping effect. Two different models are investigated. In the first case, the full length model of a ship is analyzed and a distributed load is applied with the use of a novel approach. The model is supported in the torsional centre of the cross-section, which is derived analytically. In the second case,...
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Potential and limits of landfill leachate treatment in a multi-stage subsurface flow constructed wetland – evaluation of organics and nitrogen removal
PublikacjaConstructed wetlands have potential of treating wastewater of poor biodegradability. The performance of a multistage sub-surface flow wetland treating municipal landfill leachate was assessed during three years of operation. During the study three research periods with different operation conditions were established. The hydralic loads, operation mode of vertical flow beds and type of treated wastewater (raw leachate – leachate...
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Risk Assessment at Unsignalized Intersections Based on Human-Road-Environment-Vehicle System Applying Fuzzy Logic
PublikacjaThe constant increase in motorization level and traffic density increases risks due to dangerous situations for road participants. Therefore, assessing the accident level of road network elements has been an urgent task over the past decades. However, existing approaches mainly rely on traffic flow parameters and account for dynamic vehicle characteristics. The research aims to design a model accounting for uncertain factors (weather...
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The use of a 4 PB strain sweep fatigue test to evaluate characteristics of carbon grid reinforced asphalt beams
PublikacjaThe article presents research results concerning pre-bituminized carbon grids for asphalt pavement reinforcement, which are used to prevent cracking and crack reflection thus increasing bearing capacity and durability of pavement. Research program involved testing of large sized double-layer samples, both reinforced and unreinforced. The advantage of using a carbon grid was especially visible after crack initiation. The energy...
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Bioactive compounds and the antioxidant capacity in new kiwi fruit cultivars
PublikacjaThe aim of this investigation was to find the best among seven different kiwi fruit cultivars (‘Hayward’, ‘Daheung’, ‘Haenam’, ‘Bidan’, ‘Hort16A’, ‘Hwamei’ and ‘SKK12’) for human consumption and to classify them as groups. Therefore, the contents of bioactive compounds and the level of antioxidant capacities of these cultivars were determined in four different extracts and compared. It was found that the contents of the bioactive...
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Determination of Odour Interactions in Gaseous Mixtures Using Electronic Nose Methods with Artificial Neural Networks
PublikacjaThis paper presents application of an electronic nose prototype comprised of eight sensors, five TGS-type sensors, two electrochemical sensors and one PID-type sensor, to identify odour interaction phenomenon in two-, three-, four- and five-component odorous mixtures. Typical chemical compounds, such as toluene, acetone, triethylamine, α-pinene and n-butanol, present near municipal landfills and sewage treatment plants were subjected...
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Sub-national structures matter when evaluating physical activity promotion: Lessons from Germany
PublikacjaBackground Public policies are increasingly acknowledged as important part of promoting physical activity (PA). However, especially in states with sub-national administrative structures such as Germany, national and sub-national approaches differ considerably. In Germany, sport for all (SfA) promotion is mostly organized at sub-national level, which is usually not covered in national evaluations. Knowledge of these structures helps...
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Proton transfer and hydrogen bonds in supramolecular, self-assembled structures of imidazolium silanethiolates. X-ray, spectroscopic and theoretical studies
PublikacjaThe reaction of 1-methylimidazole, 2-ethyl-4-methylimidazole and 2-ethylimidazole with tris(2,6- diisopropylphenoxy)silanethiol (TDST) leads to the formation of three new salts, which have been characterized by elemental analyses, thermogravimetric analyses, FTIR spectroscopy, and their structures were determined by single-crystal X-ray diffraction. Structural analyses indicate that in all three compounds a proton transfer has...
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New nanoadsorbent based on magnetic iron oxide containing 1,4,7,10-tetraazacyclododecane in outer chain (Fe3O4@SiO2-cyclen) for adsorption and removal of selected heavy metal ions Cd2+, Pb2+, Cu2+
PublikacjaMagnetic Fe3O4@SiO2-cyclen nanoparticles were prepared and used as adsorbent for Cd2+, Pb2+ and Cu2+ from aqueous solution removal process controlled with differential pulse anodic stripping voltammetry (DPASV) and hanging mercury drop electrode (HDME). Nanomaterial was synthesised in three-step process co-precipitation of Fe3O4 core, coating with silane and N-(3-(triethoxysilyl)propyl)-1,4,7,10-tetraazacyclododecane-1-carboxamide...
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Gesture Recognition With the Linear Optical Sensor and Recurrent Neural Networks
PublikacjaIn this paper, the optical linear sensor, a representative of low-resolution sensors, was investigated in the multiclass recognition of near-field hand gestures. The recurrent neural network (RNN) with a gated recurrent unit (GRU) memory cell was utilized as a gestures classifier. A set of 27 gestures was collected from a group of volunteers. The 27 000 sequences obtained were divided into training, validation, and test subsets....
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Employee Commitment Matters for CSR Practice, Reputation and Corporate Brand Performance—European Model
PublikacjaSo far, there have been no studies that explore how employee brand commitment moderates CSR practice outcomes. Employee brand commitment is often claimed as a focal input and output of the CSR. So, it means that it shapes CSR conditions. Then, it is a moderator. This study aims to verify it. Besides, commitment exists in many forms and can be achieved in many ways. Hence the question, if employees are committed to the brand, then...
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The effect of external load on ultrasonic wave attenuation in steel bars under bending stresses
PublikacjaThe stress state in deformed solids has a significant impact on the attenuation of an ultrasonic wave propagating through the medium. Measuring a signal with certain attenuation characteristics can therefore provide useful diagnostic information about the stress state in the structure. In this work, basic principles behind a novel attenuation-based diagnostic framework are introduced. An experimental study on steel bars under three-point...
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PROBLEMS OF COLLISIONS BETWEEN ADJACENT STEEL STRUCTURES UNDER EARTHQUAKE EXCITATION
PublikacjaNowadays, the high level of urbanization forces the engineers to design closely-separated structures and to take into account many factors influencing their response, including collisions between them due to insufficient separation distance during moderate to strong ground motions. Recent observations as well as experimental and numerical investigations have confirmed that interactions...
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Digital Government as Implementation Means for Sustainable Development Goals
PublikacjaOne of the challenges for implementing Sustainable Development Goals (SDGs) is the measurement of indicators that represent progress towards such goals. Measuring such progress enables data-driven decision-making and management of SDG-relevant projects and strategies. The premise of this research is that measuring such indicators depends on measuring so-called means of implementation, i.e. activities that directly contribute to...
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Supporting Gastroesophageal Reflux Disease Diagnostics by Using Wavelet Analysis in Esophageal pH-Metry
PublikacjaThis paper presents a new approach to computer supported esophageal pH-metry measurement analysis performed in order to diagnose gastroesophageal reflux disease. In this approach wavelet analysis was used to analyse the esophageal pH-metry course. The research was performed on three groups of pH-metry courses: whole 24-hour pH-metry course, sleep only pH-metry course and 20 minutes after the end of a meal pH-metry course. After...
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A Parallel MPI I/O Solution Supported by Byte-addressable Non-volatile RAM Distributed Cache
PublikacjaWhile many scientific, large-scale applications are data-intensive, fast and efficient I/O operations have become of key importance for HPC environments. We propose an MPI I/O extension based on in-system distributed cache with data located in Non-volatile Random Access Memory (NVRAM) available in each cluster node. The presented architecture makes effective use of NVRAM properties such as persistence and byte-level access behind...
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Comprehensive comparison of compact UWB antenna performance by means of multi-objective optimization
PublikacjaAn optimization-based procedure for comprehensive performance comparison of alternative compact UWB antenna topologies is discussed. The assessment of the antenna performance is conducted with respect to the structure size and its reflection response. More specifically, the best possible tradeoffs between these two figures of merit are identified through multiobjective optimization at the level...
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GROUPS OF GERMAN DOMESTIC APPLIANCE MANUFACTURERS ACCORDING TO NEW PRODUCT DEVELOPMENT PRACTICES
PublikacjaFinding the best way to develop new products has been always a hot topic for practitioners and academics. However, so far only a few of these kinds of studies have concentrated on a single industry. In this paper, we group German domestic appliance manufacturers with regards to their new product development (NPD) practices to discover their attitude to NPD effort. By conducting a survey we found that three different groups of manufacturers...
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Fast Full-Wave Multilevel Zero-Pole Optimization of Microwave Filters
PublikacjaA new concept is proposed for the full-wave computer-aided design of microwave filters. The method consists of two stages and operates on the zeros and poles of the transfer function and their derivatives. These quantities are evaluated from the response computed by a full-wave electromagnetic solver with two levels of accuracy. The two stages make use of different models that are optimized using a low-accuracy electromagnetic...
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Novel structure and EM-driven design of miniaturized microstrip rat-race coupler
PublikacjaIn this paper, a novel structure and design procedure of a miniaturized microstrip rat-race coupler (RRC) is described. Small size of the RRC is achieved by folding the transmission lines of the conventional circuit into its interior, as well as by implementation of the structure on three layers. The final size of the coupler realized for the operating frequency of 1 GHz is only 220 mm2, which gives over 95% footprint reduction...
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Reliable Microwave Modeling By Means of Variable-Fidelity Response Features
PublikacjaIn this work, methodologies for low-cost and reliable microwave modeling are presented using variable-fidelity response features. The two key components of our approach are: (i) a realization of the modeling process at the level of suitably selected feature points of the responses (e.g., S-parameters vs. frequency) of the structure at hand, and (ii) the exploitation of variable-fidelity EM simulation data, also for the response...
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The Use of Information and Communication Technologies in Cluster Organizations
PublikacjaThe purpose of the paper is to explore how cluster organizations (COs) take advantage of Information and Communication Technologies (ICT). The paper addresses the research question: “How do cluster organizations take advantage of ICT in fulfilling their main roles?”. The research was carried out in the first half of 2016 in four purposefully selected cluster organizations. The main research strategy involved Grounded Theory; the...
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Concentrations of monoaromatic hydrocarbons in the air of the underground car park and individual garages attached to residential buildings
PublikacjaThe paper describes the characteristics of a two-level underground car park and three individual garages attached to residential buildings, differing by the resident utilization habits, located in North Poland (Tri-City agglomeration area). The strategy of collecting the analyte samples from air in mentioned enclosed areas, concerning the determination of benzene, toluene, ethylbenzene, o-xylene and p,m-xylenes (BTEX) concentrations...
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Student model representation for pedagogical virtual mentors
PublikacjaThe paper concerns technological aspects of virtual mentors construction, especially concentrating on the student model representation. The article distinguishes several types of information that is gathered by the pedagogical agents and other educational platforms, including student knowledge model, student progress tracking, interaction process patterns and learner preferences. A set of technologies used for the student model...
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“Don’t call it work”: An interpretative phenomenological analysis of volunteer firefighting in young adults based on the volunteer process model
PublikacjaThe number of people engaging in volunteer firefighting is on the decline. It is important to understand what factors on a personal and social level and from the three stages of the volunteer process model: antecedents, experiences and consequences, might be linked to starting and sustaining such engagement. To address this problem, a qualitative, interview-based study was performed on a sample of 10 volunteer firefighters from...
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Quality evaluation of agricultural distillates using different types of electronic noses
PublikacjaThe paper presents the results of investigation on quality evaluation of agricultural distillates using a prototype of electronic nose instrument and a commercial electronic nose of Fast/Flash GC type – HERACLES II. The prototype was equipped with TGS type semiconductor sensors. HERACLES II included two chromatographic columns with different polarity of stationary phase and two FID detectors. In case of the prototype volatile fraction...