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Design and characterization of apatite La9.8Si5.7Mg0.3O26±δ-based micro-tubular solid oxide fuel cells
PublikacjaIn this study, electrolyte-supported (Cell A) and anode-supported (Cell B) micro-tubular solid oxide fuel cells (SOFCs) based on the La9.8Si5.7Mg0.3O26±δ (LSMO) electrolyte is built through an extrusion and dip-coating processes. The formulations and process conditions for these cells are established and optimized. Both cell configurations show no visible delamination or cracking, and reaction zones and inter-diffusion of any species...
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Effect of Surface Treatment of Halloysite Nanotubes (HNTs) on the Kinetics of Epoxy Resin Cure with Amines
PublikacjaThe epoxy/clay nanocomposites have been extensively considered over years because of their low cost and excellent performance. Halloysite nanotubes (HNTs) are unique 1D natural nanofillers with a hollow tubular shape and high aspect ratio. To tackle poor dispersion of the pristine halloysite (P-HNT) in the epoxy matrix, alkali surface-treated HNT (A-HNT) and epoxy silane functionalized HNT (F-HNT) were developed and cured with...
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Trace elements content of surface peat deposits in the Solovetsky Islands (White Sea)
PublikacjaPeatlands form environmental archives of trace element deposition. In this regard they are particularly valuable for areas such as the Arctic, where regular pollution monitoring is either impossible or extremely costly. The aim of this study was to assess pollution in the Solovetsky Islands (65° 05' N, 35° 53' E) by examining the spatial variability in trace element content of the uppermost layer of peat, immediately below the...
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Investigation of Acoustic Properties of Poroelastic Asphalt Mixtures in Laboratory and Field Conditions
PublikacjaMeasures for the improvement of acoustic conditions in the vicinity of roads include the construction of pavement structures with low-noise surfaces with optimal macrotexture and the highest possible sound absorption coefficient. Laboratory evaluation of acoustic properties of a designed asphalt mixture before its placement in the pavement is a good solution. Currently, the most popular method for the determination of the sound...
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Displacement piles - classification and methods for the calculation of bearing capacity.
PublikacjaDisplacement piles belong to a group of technologies whose main idea is to install or make a pile without extracting ground material. According to definition, contained in PN-EN:1997-1:2008, displacement piles should be considered as driven, pressed in using vibrators and made with the use of spread augers. The classification of piles used so far with regard to the technology of execution is modified. An additional element is the...
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Social benefits valuation of hosting non-mega sporting events
PublikacjaPurpose In the study, an attempt was made to estimate the social benefits resulting from three non-mega sporting events organized in Ergo Arena located on the border of two cities in Poland. By attributing a value to intangible social benefits, the intangible effect was determined and compared to the expenditure incurred in the construction of Ergo Arena Hall. Design/methodology/approach In order to value social intangible effects...
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Intelligent monitoring the vertical dynamics of wheeled inspection vehicles
PublikacjaThe problem of intelligent monitoring of the vertical dynamics of wheeled inspection vehicles is addressed. With the independent MacPherson suspension system installed, the basic analysis focuses on the evaluation of the parameters of the so-called quarter car model. To identify a physically motivated continuous description, in practice, dedicated integral-horizontal filters are used. The obtained discrete model, which retains...
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Badania nośności na zginanie innowacyjnego kształtownika giętego na zimno typu GEB
PublikacjaLekkie konstrukcje metalowe wytwarzane z kształtowników giętych na zimno to jedna z najszybciej rozwijających się dyscyplin w zakresie budownictwa. Do niedawna profile gięte na zimno stosowano wyłącznie jako elementy drugorzędne, czyli płatwie oraz rygle. Nowo opatentowany przekrój typu GEB ma być wykorzystywany jako element nośny konstrukcji ramowych. Jednak jego zaistnienie na rynku budowlanych konstrukcji metalowych jest uwarunkowane...
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Charakterystyka pracy instalacji fotowoltaicznej trójpłaszczyznowej małej mocy – studium przypadku
PublikacjaW artykule zaprezentowano specyfikę pracy instalacji fotowoltaicznej zainstalowanej na dachu budynku jednorodzinnego, która charakteryzuje się ułożeniem paneli fotowoltaicznych w trzech grupach, przy czym każda z tych grup ma inną orientację kierunkową. Przedstawiono kształtowanie się krzywej generacji tej instalacji oraz osiągane wartości generowanej energii elektrycznej. Wybrane aspekty pracy tej instalacji porównano z innymi...
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Stateczność czołowego obwałowania nasypu przeciwpowodziowego Jeziora Druzno
PublikacjaPrzedstawiono analizę stateczności czołowego obwałowania przeciwpowodziowego Jeziora Druzno w miejscowości Nowe Dolno. Obliczenia przeprowadzono zarówno w naprężeniach całkowitych jak i efektywnych uproszczoną metodą Bishopa oraz metodą Felleniusa-Peterssona. Uzyskano wysokie wartości minimalnego wskaźnika stateczności, zapewniające znaczny zapas stateczności nasypu podczas długotrwałych piętrzeń wody w jeziorze. Mogłoby to wskazywać...
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Trudności ochrony środowiska w planowaniu przestrzennym–struktura problemu
PublikacjaArtykuł zawiera ogólną systematykę negatywnych oddziaływań na środowisko przyrodnicze. Autor omawia trudności zapobiegania przez planowanie przestrzenne zagrożeniom środowiska. Analizuje strukturę problemu, wskazując czynniki: społeczne, gospodarcze, prawne i polityczne, w tym rolę: motywacji, hierarchii wartości, świadomości ekologicznej, przekonań. Autor wskazuje też działania prowadzące do ograniczenia zagrożeń.
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Entropy measures of heart rate variability for short ECG datasets in patients with congestive heart failure
PublikacjaWe investigated the usefulness of entropy measures calculated for short ECG series in distinguishing healthy subjects from patients with congestive heart failure (CHF). Four entropy measures were tested: Approximate Entropy (ApEn), Sample Entropy (SampEn), Fuzzy Entropy (FuzzyEn) and Permutation Entropy (PE), each computed for ECG series of 1000, 500, 250 and 100 RR intervals. We found that with a reduction of the data set length...
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Parameters optimization in medicine supporting image recognition algorithms
PublikacjaIn this paper, a procedure of automatic set up of image recognition algorithms' parameters is proposed, for the purpose of reducing the time needed for algorithms' development. The procedure is presented on two medicine supporting algorithms, performing bleeding detection in endoscopic images. Since the algorithms contain multiple parameters which must be specified, empirical testing is usually required to optimise the algorithm's...
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Automatic sound recognition for security purposes
PublikacjaIn the paper an automatic sound recognition system is presented. It forms a part of a bigger security system developed in order to monitor outdoor places for non-typical audio-visual events. The analyzed audio signal is being recorded from a microphone mounted in an outdoor place thus a non stationary noise of a significant energy is present in it. In the paper an especially designed algorithm for outdoor noise reduction is presented,...
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Street Art and Architecture
PublikacjaThe paper explores both the areas of conflict as well as agreement between architecture and Street Art. The conflict arises from the fact that urban environment has always been a background for street art, which unavoidably jeopardizes the conceptual integrity of the building understood as a work of architecture. However, there are strong interrelations between these two domains of human creativity. Both street art and architecture...
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Performance of the flat plate solar collector operated with water-Al2O3 nanofluid
PublikacjaThe paper discusses the effect of application of water-Al2O3 nanofluid, as a working fluid, on the efficiency of a flat plate solar collector. The mass concentration of nanoparticles was 0.1%, 0.2% and 0.4%. The tests were conducted for two values of radiation of about 1050 W/m2 and 400 W/m2, and volume flow rates of 60 l/h, 120 l/h and 170 l/h. The efficiency was calculated according to recommendations of the Polish Standard....
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Exploration of optical fibres as a carrier for new benzene and toluene matrix-free reference materials
PublikacjaTo meet high expectations concerning precision and accuracy of reference materials, preparation of matrixfree reference materials using thermal decomposition-gas chromatography-mass spectrometry (TD-GC-MS) was proposed in this study. In the paper, the results obtained in preparation of the new reference materials for benzene and toluene are presented, based on the thermal decomposition technique of compounds chemically bound to...
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Visual Lip Contour Detection for the Purpose of Speech Recognition
PublikacjaA method for visual detection of lip contours in frontal recordings of speakers is described and evaluated. The purpose of the method is to facilitate speech recognition with visual features extracted from a mouth region. Different Active Appearance Models are employed for finding lips in video frames and for lip shape and texture statistical description. Search initialization procedure is proposed and error measure values are...
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AN INNOVATIVE APPROACH TO PREDICTION ENERGETIC EFFECTS OF WOOD CUTTING PROCESS WITH CIRCULAR-SAW BLADES
PublikacjaIn the classical approach, energetic effects (cutting forces and cutting power) of wood sawing process are generally calculated on the basis of the specific cutting resistance, which is in the case of wood cutting the function of more or less important factors. The aim of the paper is to present a new calculating model using the application of modern fracture mechanics and to compare cutting parameters of native beech, Bendywood...
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Symmetry-Breaking Bifurcation for Free Elastic Shell of Biological Cluster, Part 2
PublikacjaWe will be concerned with a two-dimensional mathematical model for a free elastic shell of biological cluster. The cluster boundary is connected with its kernel by elastic links. The inside part is filled with compressed gas or fluid. Equilibrium forms of the shell of biological cluster may be found as solutions of a certain nonlinear functional-differential equation with several physical parameters. For each multiparameter this...
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Fracture mechanics model of cutting power versus widespread regression equations while wood sawing with circular saw blades
PublikacjaA 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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Empirical verification in industrial conditions of fracture mechanics models of cutting power prediction
PublikacjaA comparison of experimental results obtained in the industrial conditions at a sawmill located in the Baltic Natural Forest Region (PL) and theoretical cutting power consumption forecasted with the models which include work of separation (fracture toughness) in addition to plasticity and friction has been described. In computations of cutting power consumption during rip sawing of Scots pine wood (Pinus sylvestris L.) values of...
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Heat Transfer During Pool Boiling of Water, Methanol and R141b on Porous Coated Horizontal Tube Bundles
PublikacjaThis paper presents the results of experimental investigation of water, methanol and R141b refrigerant boiling on horizontal porous coated tube bundles supposed to represent a flooded-type evaporator. Experiments were carried out for a bundle of 19 tubes in triangular layout for two pitch-to-diameter ratio values – 1.7 and 2.0 – in atmospheric and sub-atmospheric pressure conditions. Average heat transfer coefficients – both local,...
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Thermodynamic analysis of the double Brayton cycle with the use of oxy combustion and capture of CO2
PublikacjaIn this paper, thermodynamic analysis of a proposed innovative double Brayton cycle with the use of oxy combustion and capture of CO2, is presented. For that purpose, the computation flow mechanics (CFM) approach has been developed. The double Brayton cycle (DBC) consists of primary Brayton and secondary inverse Brayton cycle. Inversion means that the role of the compressor and the gas turbine is changed and firstly we have expansion...
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Entropy Measures of heart rate variability for short ECG datasets in patients with congestive heart failure
PublikacjaWe investigated the usefulness of entropy measures calculated for short ECG series in distinguishing healthy subjects from patients with congestive heart failure (CHF). Four entropy measures were tested: Approximate Entropy (ApEn), Sample Entropy (SampEn), Fuzzy Entropy (Fuzzy En) and Permutation Entropy (PE), each computed for ECG series of 1000, 500, 250 and 100 RR intervals. We found that with a reduction of the data set length...
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FDTD-Compatible Green's function based on scalar discrete Green's function and multidimensional Z-transform
PublikacjaIn this contribution, a new formulation of the discrete Green's function (DGF) is presented for the finitedifference time-domain (FDTD) grid. Recently, dyadic DGF has been derived from the impulse response of the discretized scalar wave equation (i.e., scalar DGF) with the use of the multidimensional Z-transform. Its software implementation is straightforward because only elementary functions are involved and a single function...
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Euro 2012 in Gdańsk, Poland. Is it worth using public funds?
PublikacjaThe aim of this study is to estimate the willingness - to - pay (WTP) among the community of the Pomeranian region, Poland in connection with intangible benefits and costs st emming from hosting the Euro 2012 in Gdansk. A survey conducted among 407 respondents was the source of information. The results of the study show that the average value of WTP benefit for the whole sample was 45,72 PLN2012 and WTP cost...
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Construction solutions for historical object foundations in the context of changing their functional use
PublikacjaProperly executed renovation and adaptation of a grade listed property not only ensures its constructional safety, but may also highlight the object’s historical value. Taking into consideration various factors, such as divergence of interests, or technical and legal determinants, it is safe to say that the renovation and adaptation of grade listed properties for new purposes is a complex process. The authors of the paper wish...
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Analiza i ocena smarności olejów w ujęciu energetycznym i działania układu tribologicznego = Analysis and evaluation of oil lubricity from the viewpoint of energy apects and of the tribological system action
PublikacjaBased on measurement results, an interpretation is presented of the tribological system boundary layer action in the form of a four-ball tester friction node. The evaluation was performed of the boundary layer action understood as transfer of energy Ep resulting from loading the tribological system in a determined time t with work Lp, which may lead to breaking the boundary layer. That energy and time are the values unequivocally...
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The impact of the distribution network reconfiguration on active power losses: Selected issues of UPGRID project realization
PublikacjaThe dynamic development of smart grids allows the use of remote controllable switches to change the configuration of the distribution network. The paper discusses the impact of the distribution system reconfiguration on active power losses, taking into account the typical daily load profiles. Based on modified IEEE 33-bus test distribution system the article presents the method of selection the appropriate sensitivity factor and...
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Comment on "On accurate capacitance characterization of organic photovoltaic cells"
PublikacjaIn the 100th volume of Applied Physics Letters Carr and Chaudhary have presented a work on capacitance characterization of organic photovoltaic cells. The work concerns small signal measurements of various organic photovoltaic structures. The authors however limit their considerations to one part of small signal response, namely to capacitance measured either in parallel mode or in series mode. This attitude generally does not...
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Structural Factors Affecting Cytotoxic Activity of (E)-1-(Benzo[d ][1,3]oxathiol-6-yl)-3-phenylprop-2-en-1-one Derivatives
PublikacjaDerivatives of (E)-1-(5-alkoxybenzo[d][1,3]oxathiol-6-yl)-3-phenylprop-2-en-1-one (1) demonstrated exceptionally high in vitro cytotoxic activity, with IC50 values of the most active derivatives in the nanomolar range. To identify structural fragments necessary for the activity, several analogs deprived of selected fragments were prepared, and their cytotoxic activity was tested. It was found that the activity depends on combined effects...
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Analysis of EN 1993-1-6 guidelines about determining amplitudes of equivalent imperfections of steel cylindrical shells subjected to uniform external pressure
PublikacjaCivil engineering structures should be designed with reference to relevant standards. One of them is a Eurocode 3 standard EN 1993-1-6:2007: Design of steel structures Part 1-6: Strength and Stability of Shell Structures. According to this standard, the value of buckling load can be determined using different approaches: classical hand calculations (stress design) and geometrical and material non-linear analysis of an imperfect...
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The σ-phase superconductors Nb20.4Rh5.7Ge3.9 and Nb20.4Rh5.7Si3.9
PublikacjaWe show that the previously unreported ternary σ phases Nb20.4Rh5.7Ge3.9 and Nb20.4Rh5.7Si3.9 are both superconductors with Tc values of approximately 1.9 K. The superconducting transitions were characterized through temperature-dependent magnetic susceptibility, electrical resistance, and specific heat measurements. The Sommerfeld constants, γ, for Nb20.4Rh5.7Ge3.9 and Nb20.4Rh5.7Si3.9 are 89(1) mJ mol-f.u.−1K−2 and 86(1) mJ mol-f.u.−1K−2...
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Characterization of Slow and Fast Fading in Off-Body Communication at 2.45 GHz with Space Diversity Scheme in an Indoor Environment
PublikacjaThe characterization of slow and fast fading in wireless body area networks with space diversity scheme has been presented. The analysis, based on the measurements at 2.45 GHz in an indoor environment, has shown that for all investigated configurations of receiving wearable antennas, the correlation coefficient values of the received signals’ parameters are below the assumed value of 0.5, being close to zero for the vast majority...
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Influence of Wood Moisture on Strength and Elastic Modulus for Pine and Fir Wood Subjected to 4-point Bending Tests
PublikacjaThe main purpose of this research paper was to determine the influence of the wood moisture on the strength and elastic modulus of pine and fir wood specimens subjected to the 4-point bending tests. Six bending tests for each wood species and for two different moisture level have been performed. Then, the advanced statistical analysis of the results has been carried out. On the basis of the obtained results, it has been noted that...
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Second-order Stark effect and polarizability of a relativistic two-dimensional hydrogenlike atom in the ground state
PublikacjaThe second-order Stark effect for a planar Dirac one-electron atom in the ground state is analyzed within the framework of the Rayleigh-Schrödinger perturbation theory, with the use of the Sturmian series expansion of the generalized Dirac-Coulomb Green's function. A closed-form analytical expression for the static dipole polarizability of that system is found. The formula involves the generalized hypergeometric function ${}_{3}F_{2}$...
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Structural Health Monitoring of Composite Shell Footbridge for Its Design Validation
PublikacjaThe paper presents the structural health monitoring system of the composite bridge for pedestrians and cyclists. The footbridge was designed and manufactured within the FOBRIDGE project. It is the first bridge in the world, which is classified as a consistent single element structural girder, made of sandwich shells, entirely produced in a single cycle. The developed structural health monitoring system, supported design process,...
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A decision-making system supporting selection of commanded outputs for a ship's propulsion system with a controllable pitch propeller
PublikacjaThe ship's operators have to make decisions regarding the values of commanded outputs (commanded engine speed and pitch ratio) which ensure maximum vessel speed and minimum fuel consumption. Obviously, the presented decision problems are opposed. Therefore, there is a need for a compromise solution that enables more flexible vessel voyage planning. This paper deals with development of a computer-aided system supporting selection...
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Simulation of the remanence influence on the transient states in a single-phase multiwinding transformer
PublikacjaThis paper presents the mathematical model of a single-phase multi-winding core type transformer taking into account magnetic hysteresis phenomenon based on the feedback Preisach model (FPM). The set of loop differential equations was developed for a K-th winding transformer model where the flux linkages of each winding includes flux Φ common to all windings as a function of magneto motive force Θ of all windings. The first purpose...
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An assessment of teeth quality of the mini gang saw blade
PublikacjaIn this work, the assessment of the effect of the operating time (90 min.) of the mini gang saw blades during sawing Scotch pine (Pinus sylvestris L.) samples upon changes of the saw blade teeth sharpness (bluntness), which was defined as an effective radius of the nose ρ , has been described. The research activities have been carried out on the Nikon Ti-S optical microscope equipped with the Nikon DS-30W camera allowing high-speed...
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Optical activity and electro-optic effect of l-arginine doped KDP single crystals
PublikacjaWe have used the modified polarimetric methods to study optical activity (OA) in the potassium dihydrogenphosphate (KDP) crystals doped with 0.7, 1.4 and 3.8 wt% L-arginine (L-arg) amino acid. Crystals were grown by the temperature reduction method. Small changes of the absolute eigen waves ellipticity and OA values in doped crystals were noted. We have experimentally determined the signs of OA in the [1 00] and [01 0] directions...
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SELECTED COMBINED POWER SYSTEMS CONSISTED OF SELFIGNITION ENGINE AND STEAM TURBINE
PublikacjaThis paper presents optimization of selected combined diesel engine-steam turbine systems. Two systems: the system combined with waste heat one-pressure boiler only and its version containing additionally low-pressure boiler proper feeding degasifier and the system of two-pressure cycle, were taken into considerations. Their surplus values of power output and efficiency associated with utilization of waste heat contained in piston...
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Characterization of slow and fast fading in off-body communication at 2.45 GHz with space diversity scheme in indoor environment
PublikacjaThe characterization of slow and fast fading in Wireless Body Area Networks with space diversity scheme has been presented. The analysis, based on the measurements at 2.45 GHz in indoor environment, has shown that for all investigated configurations of receiving wearable antennas the correlation coefficient values of received signals’ parameters are below the assumed value of 0.5, being close to zero for the vast majority of cases. It...
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Zastosowanie metody czasoprzestrzennych objętości skończonych do rozwiązania wybranych zagadnień nieustalonego przepływu w kanale otwartym.
PublikacjaW referacie przedstawiono przykłady zastosowania stosunkowo nowej metody czasoprzestrzennych objętości skończonych, zaproponowanej przez Changa (1995), a zaadaptowanej do rozwiązania problemów opisanych układem równań de Saint-Venanta. Podstawą obliczeń w metodzie jest bilans strumieni, a cechą wyróżniającą to podejście jest unifikacja zmiennych niezależnych przestrzennych i czasowych i traktowanie ich w sposób równorzędny. W efekcie...
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O MNIEJ LUB BARDZIEJ SŁODKIM CUKRZE, CZYLI KILKA UWAG O ODPOWIEDZIALNOŚCI SPOŁECZNEJ FIRM RODZINNYCH I PRZEDSIĘBIORSTW SPOŁECZNYCH
PublikacjaW artykule, przyjmując za punkt wyjścia teorię interesariuszy Freemana, autorki podjęły się refleksji na temat specyfiki odpowiedzialności społecznej firm rodzinnych i przedsiębiorstw społecznych. Przedsiębiorstwa społeczne, uznawane są powszechnie za ucieleśnienie pełnej, wręcz doskonałej formy odpowiedzialności społecznej. Z kolei przedsiębiorstwa rodzinne, charakteryzują się szczególną paletą interesariuszy oraz specyficznymi...
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Modelowanie i symulacja dynamiki ruchu trakcyjnego odbieraka prądu
PublikacjaW artykule przedstawiono dwa modele matematyczne kolejowych odbieraków prądu. Model podstawowy opracowano na podstawie analizy konstrukcji odbieraka ze stopniami swobody w ruchu obrotowym i postępowym. Drugi tzw. model zastępczy ma obydwa stopnie swobody w ruchu postępowym. Przedstawiono prosty sposób wyznaczenia wartości parametrów modelu zastępczego na podstawie wyników symulacji modelu odbieraka podstawowego. Model zastępczy,...
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Architektura i woda - przekraczanie granic
PublikacjaPublikacja daje wgląd w procesy kształtowania połączeń wody i form zbudowanych. W obserwowanych współcześnie eksperymentach struktury budynków przeplatają się z zarysami pól wodnych, powstają konstrukcje architektoniczne unoszące się na różnego rodzaju platformach pływających. Woda jest także coraz częściej włączana w projekty urbanistyczne. Linie styku pomiędzy lądem i wodą ulegają modyfikacjom, przywraca się dawne kanały i tworzy...
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Sposoby przykładania obciążenia zmiennego na konstrukcję płytowo-słupową
PublikacjaW pracy przedstawiono analizę porównawczą wybranych metod zadawania obciążenia zmiennego na konstrukcje płytowo-słupową. Przeanalizowano pięć sposobów rozkładu obciążenia na płytę stropową. Wyniki momentów zginających i przemieszczeń w wybranych punktach dla analizowanych przypadków porównywano z wartościami ekstremalnymi obliczonymi na podstawie powierzchni wpływu (Wariant 1). Wykonane obliczenia pozwoliły na wskazanie zalecanej...
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3D Hand Shape Modeling for Automatic Assessing Motor Performance in Parkinson's Disease
PublikacjaIn this paper a method for hand pattern processing to create a 3D hand model is presented. By applying a complete hand armature to the model obtained, an interpolation of three motor tests for an individual Parkinson's disease patient can be performed. To obtain the 3D hand model the top view of the hand from a web cam is analyzed. The hand contour is examined to find characteristic points that allows for dividing hand image into...