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Obliczeniowa dynamika płynów w analizie zagadnień smarowaniahydrodynamicznego = CFD in analysis of hydrodynamic lubrication
PublikacjaW pracy przedstawiono wybrane problemy związane z wykorzystaniem obliczeniowej dynamiki płynów (ang. CFD - Computational Fluid Dynamics)do obliczeń łożysk hydrodynamicznych. Omówione zostało zagadnienie przyjmowania rodzaju przepływu w analizie łożyska oraz przyjmowania warunków brzegowych dotyczących wymiany ciepła oraz problem zbieżności obliczeń.
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Free convection of water-Al2O3 nanofluid from horizontal porous coated tube
PublikacjaThe main aim of the present study was to investigate the influence of nanoparticles on heat transfer coefficients during free convection of water-Al2O3 nanofluid from horizontal porous coated tube under atmospheric pressure for nanoparticle concentration of 0.01% by weight. Contrary to published data present study concerns on free convection of nanofluids in extensive, quiescent fluid.
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Overflowing tests at the Polish DredgDikes research dike – stability of the dike surface against erosion
PublikacjaIn the project DredgDikes the different research dike embankments were tested with respect to overflowing water induced erosion. Therefore, flumes were installed on the land side embankments in which the effect of overflowing water on the vegetated surface was investigated. On the Polish DredgDikes research dike near Gdansk, Poland, two parallel flumes were installed and the surface of the dike made of different mixtures of...
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The flavour of fruit spirits and fruit liqueurs: a review
PublikacjaFruit spirits and liqueurs are among the most popular spirit-based beverages made from fruits such as plums, cherries, melon, apple, citrus and pear. The types of fruits and production methods have a great significance for the quality of the final product. The production process of spirits consists of the following stages: fermentation, distillation and maturation. For this reason scientists started to investigate the composition...
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On the lower smoothing bound in identification of time-varying systems
PublikacjaIn certain applications of nonstationary system identification the model-based decisions can be postponed, i.e. executed with a delay. This allows one to incorporate in the identification process not only the currently available information, but also a number of ''future'' data points. The resulting estimation schemes, which involve smoothing, are not causal. Assuming that the infinite observation history is available, the paper...
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Terminal charging scheduling of battery electric buses based on vehicle routing problem
PublikacjaElectric buses are considered to be a viable solution for reducing emission in dense urban areas. However, the greater charging time is a huge challenge for operators. In this paper, charging scheduling method was elaborated based on vehicle routing problem using mixed-integer linear programming model. The main novelty of the paper is the combination of modelling aspect, namely flexible turn sequence and heterogeneous shared charging...
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Optimised allocation of actuators for DWDS
PublikacjaThis paper addresses the problem of actuators’ allocation within networked structured system, namely allocation of disinfectant booster stations within Drinking Water Distribution System (DWDS), under receding horizon optimised control – Model Predictive Control (MPC) to be exact. The allocation task is kept within dynamic multiobjective optimisation framework. The MPC is defined as a single objective predictive operator. Two numerical...
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Wybrane zagadnienia przepływowe turbiny gazowej pracującej w tłoczni gazu ziemnego.
PublikacjaW niniejszym artykule przedstawiono cieplno-przepływowe obliczenia turbiny gazowej, stanowiącej napęd sprężarki w tłoczni gazu ziemnego. Wartości parametrów wejściowych niezbędnych do przeprowadzenia obliczeń przyjęto na podstawie danych technicznych tłoczni zasilających polski odcinek gazociągu tranzytowego Jamał-Europa, w których pracują turbiny gazowe SGT-600 firmy Siemens, o mocy 25,3 MW.
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Numerical study of turbulent flow and heat transfer of nanofluids in pipes
PublikacjaIn this work, Nusselt number and friction factor are calculated numerically for turbulent pipe flow (6 000 < Re < 12 000) with constant heat flux boundary condition using nanofluids. The nanofluid is modelled with the single-phase approach and the simulation results are compared with experimental data of Vajjha et al. [1]. Ethylene glycol and water, 60:40 EG/W mass ratio, as base fluid and SiO2 nanoparticles are used as nanofluid...
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Performance of the domestic micro ORC equipped with the shell-and-tube condenser with minichannels
PublikacjaIn this paper, the original compact shell-and-tube heat exchanger with circular minichannels of in-house design and manufacturing is presented as the condenser for the domestic micro heat and power plant investigations as well as other future technical applications. The heat exchanger is equipped with turbulizing baffles inside the shell. The shell itself is made of a tubular sleeve having an inner diameter of 0.067 m and the length...
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Electrophoretic Deposition and Characteristics of Chitosan–Nanosilver Composite Coatings on a Nanotubular TiO2 Layer
PublikacjaThe surface treatment of titanium implants has been applied mainly to increase surface bioactivity and, more recently, to introduce antibacterial properties. To this end, composite coatings have been investigated, particularly those based on hydroxyapatite. The present research was aimed at the development of another coating type, chitosan–nanosilver, deposited on a Ti13Zr13Nb alloy. The research comprised characterization of the...
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Cooperation of ORC installation with a gas boiler as a perspective co-generation system for households
PublikacjaThis paper reports tests of an innovative micro-CHP unit prototype, consisting of a traditional gas boiler and organic Rankine cycle (ORC), which incorporates original system components such as an axial vapour microturbine, evaporator and condenser. The system co-generates heat and electricity for a single household or a group of households. Electricity is only a by-product during production of heat. While testing the prototype,...
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Experimental study on single phase operation of microjet augmented heat exchanger with enhanced heat transfer surface
PublikacjaThe article presents experimental investigations on a prototype heat exchanger. Presented research is focused on combined active and passive enhancement techniques of surface modification and microjet impingement. The results were compared to reference plate heat exchanger without microjet impingement. The Wilson plot method was applied to determine the heat transfer coefficients in the single phase operation. The heat exchanger...
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Minichannel and minigap classification criteria based on the aspect ratio of the minigeometry: A numerical study
PublikacjaA detailed numerical investigation has been carried out to analyze the diabatic flow distribution and velocity profile in 18 minigeometries with various aspect ratios for V-type and I-type flow configurations (for 36 cases) assuming ethanol as a working fluid. The aim of the study is to distinguish the value of the aspect ratio for which the flow in minigeometry starts to be two-dimensional (minigap). Cases with a constant Reynolds...
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Experimental study of flow boiling pressure drop and heat transfer of R1233zd(E) at moderate and high saturation temperatures
PublikacjaThe paper presents the results of experimental study of flow boiling of R1233zd(E) in minichannel at moderate and high saturation temperatures. The heat transfer coefficient and pressure drop were measured for flow boiling in a stainless steel tube with 2 mm inside diameter and a length of 300 mm. Experiment has been conducted for saturation temperatures ranging from 83 to 145 °C which corresponds to values of reduced pressures...
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Human capital quality indicators for measuring regional knowledge economy advances
PublikacjaBuilding Knowledge Economies (KE) is a long-term process. However, civilizational and technological changes together with EU's Lisbon Strategy help in creating solutions that may speed up economical growth of countries and their regions. This seems to be a very important issue, as during last two centuries history shown, that wisdom and human invention and innovation are the most important factor driving economical growth. In this...
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Effect of organic nitrogen concentration on the efficiency of trickling filters
PublikacjaThe study was conducted in Poland at six selected wastewater treatment plants (WWTP) based on the trickling filters Bioclere® technology. The aim of the study was to find the relationship between the influent organic nitrogen concentration and the purification efficiency expressed as effluent COD concentration. In the tests performed, the COD to BOD5 relationship was close to 2 and the ratio of BOD5 to TN was lower than 4. The...
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Application of Barkhausen method to determine internal stresses in cold-rolled and hot-rolled sheets
PublikacjaThe paper presents investigations on internal stress distribution in plane hot—or cold-rolled sheets dedicated for the cold-formed profiles. The motivation of the research is a new profile design whose bending technology, incorporating a longitudinal welded joint and hot-dip galvanization after bending and welding introduces additional internal stresses. In order to identify the entirety of stresses in the process of sheet production...
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Problems of Flaking in Strengthening Shaft Burnishing
PublikacjaThe article presents the results of testing the surface condition of shafts manufactured by a strengthening rolling burnishing process. The shafts with a hardness about 220 HB were burnished with a roller with different force. Researches were carried out with particular attention to the structure of the outflowing material in the tool zone during burnishing process. The article presents the results of the examinations of burnished...
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DYNAMIC RESPONSE OF FORUM GDANSK STRUCTURE DUE TO RAIL TRAFFIC
PublikacjaThe paper presents the study of the impact of vibration induced by the movement of the railway rolling stock on the Forum Gdańsk structure. This object is currently under construction and is located over the railway tracks in the vicinity of the Gdańsk Główny and Gdańsk Śródmieście railway stations. The analysis covers the influence of vibrations on the structure itself and on the people within. The in situ measurements on existing...
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Variations of Ship’s Deck Elevation Due to Stochastic Process of Containers Loading
PublikacjaThe stochastic process of container loading is described in the paper with special emphasis to ship motion when she is lying at a quay. The 3 DOF system was applied to describe rolling, pitching and heaving of a vessel which may cause a significant variations of momentary deck elevation. The realistic range of such variations are assessed for a variety of cargo locations on-board and a phase shift between two independent gantries...
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[Chapter] 22. Application of physical modeling to study combustion process-es and flow patterns in large-scale boilers and furmaces. W: Optical me- thods and data processing in heat and fluid flow. Ed. C. Greated, J. Cos-grove, J.M. Buick. Bury St. Edmunds. London: Profess. Eng. Publ.**2002 s. 267-277, 4 rys. bibliogr. 6 poz. Zastosowanie modelowania fizycznego do badania procesów spalania pola prze- pływu w przemysłowych kotłach i piecach.
PublikacjaRozdział zawiera wyniki badań modelowania fizycznego dwuwymiarowego i trój-wymiarowego pola przepływu i procesów spalania w wybranych urządzeniachprzemysłowych.
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Alternative cogeneration thermodynamic cycles for domestic ORC
PublikacjaThe Organic Flash Cycle (OFC) is suggested as a vapor power cycle that could potentially improve the efficiency of utilization of the heat source. Low and medium temperature finite thermal sources are considered in the cycle. Additionally the OFC’s aim is to reduce temperature difference during heat addition. The study examines 2 different fluids. Comparisons are drawn between the OFC and an optimized basic Organic Rankine Cycle...
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In vitro biodegradation of bacterial nanocellulose under conditions simulating human plasma in the presence of selected pathogenic microorganisms
PublikacjaThe Biodegradability of bacterial nanocellulose (BNC) was assessed based on a change in its properties under conditions simulating human plasma in the presence or absence of the pathogens Staphylococcus aureus, Candida albicans and Aspergillus fumigatus. It was shown that the dry mass of BNC did not change during 6 months of incubation, except for samples stored in the presence of moulds, where the dry mass reduced by 40 %. The...
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Estimation of wind pressure acting on the new palm house in Gdansk
PublikacjaThis paper deals with the problem of numerical simulations of wind loads acting on a Palm House with complex geometry. Flow simulations with aid of computational fluid dynamics procedures have been performed to check if the pressure distributions for the structure are greater than those calculated using the standard design codes with assumption that the Palm House horizontal cross sections are described by smooth cylinders.
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Investigation of the Combustion Processes in the Gas Turbine Module of an FPSO Operating on Associated Gas Conversion Products
PublikacjaIn this paper, we consider the issue of thermo-chemical heat recovery of waste heat from gas turbine engines for the steam conversion of associated gas for offshore vessels. Current trends in the development of offshore infrastructure are identified, and the composition of power plants for mobile offshore drilling units and FPSO vessels is analyzed. We present the results of a comparison of power-to-volume ratio, power-to-weight...
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ROLA I ZNACZENIE SYSTEMÓW PRZELEWÓW NATYCHMIASTOWYCH A OBRÓT BEZGOTÓWKOWY W POLSCE
PublikacjaCelem pracy jest opis systemów szybkich przelewów w Polsce z uwagi na rosnące znaczenie obrotu bezgotówkowego. Artykuł wskazuje na genezę powstania systemów oraz ich rosnące znaczenie na rynku usług płatniczych. Celem szczegółowym jest zobrazowanie wzrostu liczby i wartości transakcji zrealizowanych przez systemy płatności natychmiastowych w Polsce oraz odniesienie wolumenu do statystyk systemu Elixir. Autor obrazuje korzyści płynące...
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Social Differentiation of the Perception and Human Tissues Donation for Research Purposes.
PublikacjaThe willingness to donate human biological material for research purposes is shaped by socio-cultural factors; however, there is a lack of studies analysing the social perception of different human tissues, which may affect such willingness. This study aimed to distinguish different sociocultural categories of human tissues and types of potential donors based on their willingness to donate material. Quantitative research was...
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DYNAMIC ANALYSIS OF THE RAILWAY BRIDGES IN POLAND WITH REGARDS TO HIGH-SPEED TRAINS PASSAGE ADJUSTMENT
PublikacjaThe dynamic analysis of the railway bridge in Tczew was carried out in the article as an example of such bridges adaptation suitability to handle high-speed trains. Calculations of railway bridges are greatly complicated and labor-consuming. The bridge model and a rolling stock passage simulation were developed in the SOFISTIK software. Three types of elements were used for the correct mapping of the structure in the calculation...
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Adversarial attack algorithm for traffic sign recognition
PublikacjaDeep learning suffers from the threat of adversarial attacks, and its defense methods have become a research hotspot. In all applications of deep learning, intelligent driving is an important and promising one, facing serious threat of adversarial attack in the meanwhile. To address the adversarial attack, this paper takes the traffic sign recognition as a typical object, for it is the core function of intelligent driving. Considering...
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Badania eksperymentalne i numeryczne zachowania się zbiorników stalowych poddanych wstrząsom górniczym i sejsmicznym
PublikacjaW niniejszej dysertacji opisano wyniki kompleksowych badań zachowania się zbiorników stalowych poddanych wstrząsom górniczym i umiarkowanym trzęsieniom ziemi. Badania prowadzono dla dwóch zbiorników rzeczywistych zlokalizowanych na terenie Polski. W pierwszym etapie badań przeprowadzono badania eksperymentalne na specjalnym stanowisku laboratoryjnym dla modeli doświadczalnych zbiorników. Badania prowadzono dla różnego poziomu wypełnienia...
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Thermal energy storage using stearic acid as PCM material
PublikacjaThis work presents an experimental study of thermal energy storage by use of PCM. The aim of the study was to establish the influence of different inlet temperature of heat transfer fluid (HTF) and different Reynolds number of HTF on intensity of charging process. The PCM used in this study was stearic acid and water was used as HTF. A copper helical coil mounted in cylindrical container served as a heat transfer surface.
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BIOMATERIALS AND IMPLANTS IN CARDIAC AND VASCULAR SURGERY - REVIEW
PublikacjaCurrently, on prosthesis in cardiac blood vessels and heart valves are used materials of animal or synthetic origin. For animal materials include, among others pericardial sac in which is the heart. Materials such as this (natural) are characterized by a remarkable biocompatibility within the human body, but their main disadvantage is the relatively low durability. In turn, synthetic materials, which include the austenitic chromium-nickel-molybdenum...
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Application of microturbines in CHP systems with reciprocating engines
PublikacjaThe analysis was carried out for Combined Heat and Power generation systems with micro-turbines power plants working on heat rejected from the reciprocating engine. The calculations were performed for GE Jerbacher engines of J320 GS- C05, J320 GS- C25 and J416 GS- B05 types. We considered different working media (both wet and dry fluids): water, ammonia, ethanol, methanol, methylacetylene (propyne), dimethyloether, sulphur dioxide,...
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Trends in the new generation of green solvents in extraction processes
PublikacjaAnalytical chemistry, like other scientific fields, has undergone a number of changes to make it more consistent with the concept of sustainable development. Among the various steps of chemical analysis, without a doubt, sample preparation is the bottleneck in regard to following a green protocol, especially in terms of solvent consumption. Therefore, many attempts have been made to improve the environmental friendliness of this...
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A structure and design of a novel compact UWB MIMO antenna
PublikacjaIn the paper, a concept and design procedure of a novel compact MIMO slot antenna is presented. In order to achieve a better filling of available space, individual antennas are constrained to a triangular shape and optimized for a reduced size. The MIMO structure is then assembled using the two of previously designed antennas in orthogonal arrangement. Surrogate-assisted numerical optimization involving variable-fidelity electromagnetic...
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A modified method of vibration surveillance by using the optimal control at energy performance index
PublikacjaA method of vibration surveillance by using the optimal control at energy performance index has been creatively modified. The suggested original modification depends on consideration of direct relationship between the measured acceleration signal and the optimal control command. The paper presents the results of experiments and Hardware- in-the-loop simulations of a new active vibration reduction algorithm based on the energy...
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The initial selection of parameters for dynamic brake for car engine test dynamometer
PublikacjaThe article presents an analysis of the car engine loads. The aim of the analysis was to determine the parameters of the brake / electric motor on an engine test bad. Analysis of loads on the driving tests concerned on chassis dynamo to simulate them on an engine dynamometer. To check the range of dynamometer shaft angular acceleration inertial mass of a car was reduced on the crankshaft axis. The calculations of maximum shaft...
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The impact of methods the stochastic analysis on swimming safety of multihull floating units (Part 2)
PublikacjaIn part 2 the equations of the catamaran motion were divided into the system of two groups not conjugated with themselves containing the mutually conjugated equations. The feedback is obtained by the linear and nonlinear coefficients of dampening and coefficients of hydrostatic elasticity. The first group includes the symmetric movements (longitudinal movements), and the second group includes the antisymmetric movements (transverse)....
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Real-time simulator of agricultural biogas plant
PublikacjaThis article presents a real-time simulator of an agricultural biogas plant. The project contains biogas and biomass circuits simulation, as well as heating circuit simulation with a complete control system and visualization interface of the whole process. The software tool used to simulate the plant work is CFD (Computational Fluid Dynamics), which enables a user to create and test simulation objects based on fundamental physical...
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NUMERICAL ANALYSIS OF SPECIES DIFFUSION AND METHANOL DECOMPOSITION IN THERMOCATALYTIC REACTOR BASED ON THE INTERMETALLIC PHASE OF Ni3Al FOR LOW REYNOLDS NUMBERS
PublikacjaNumerical modelling of hydrogen production by means of methanol decomposition in a thermocatalytic reactor using corrugated foil made of the Ni3Al intermetallic phase is shown in the paper. Experimental results of the flow analysis of mixtures containing helium and methanol in a thermocatalytic reactor with microchannels were used for the initial calibration of the CFD calculations (calculations based on the Computational Fluid...
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Analysis of the influence of polystyrene microplastics and their derivatives on the DNA of human colon epithelial cells HT29 with the comet assay
PublikacjaWe have been using plastic for almost a century and nowadays a lot of them circulates as pollutants in the environment and still defragmenting to micro and nanoscale. The exposition through the food chain and its precise impact on human health is still not clear. In our study, we tested real food packaging after contact with food products and real thermoinsulation and environmental samples of polystyrene in different model liquids,...
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Modelowanie przepływu oleju pomiędzy klockami wzdłużnego łożyska ślizgowego
PublikacjaW pracy przedstawiono model MES wzdłużnego łożyska ślizgowego, wykonany przy pomocy programu ANSYS. Prezentowany model umożliwia badanie przypadków smarowania zanurzeniowego oraz smarowania wymuszonego. Przedstawiono korzyści stosowania technik CFD (Computational Fluid Dynamic) pozwalających na obserwację ruchu oleju pomiędzy klockami łożyska ślizgowego w przypadku nietypowych konstrukcji systemów smarowania.
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Free-surface elevation in open vortex flow controls
PublikacjaRotational form of fluid motion is complex, but very important in science and technology. The paper is devoted to the hydraulic mechanism of flow in open vortex flow controls, or regulators. The velocity field was described by the kinematic model, and intensity of rotation - by means of the energy balance between the input and dissipation. In consequence some algebraic expresions were obtained, which can be useful in approximated...
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Runoff Water
PublikacjaThis entry summarizes the current state of knowledge on the role of atmospheric pollutants' transport to the surface and transformations of wet deposition on contact with various surfaces. Runoff waters are one of the forms in which precipitation reaches the groundwater and surface water. They are formed when rain or melting snow washes the surfaces of roofs, highways, agricultural areas, or tree canopies. Pollutants present in...
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Smoking: Traditional
PublikacjaSmoking, drying, and salting belong to the oldest methods of food preservation. Meat hung by the fire was preserved by a combination of drying and smoking. Often the raw material was first pickled in brine. In different regions of the world various procedures have been developed, best suited for treating meats and fish for specific purposes. Smoking extended the shelf life and imparted very desirable, new sensory properties to...
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ColorNephroNet: Kidney tumor malignancy prediction using medical image colorization
PublikacjaRenal tumor malignancy classification is one of the crucial tasks in urology, being a primary factor included in the decision of whether to perform kidney removal surgery (nephrectomy) or not. Currently, tumor malignancy prediction is determined by the radiological diagnosis based on computed tomography (CT) images. However, it is estimated that up to 16% of nephrectomies could have been avoided because the tumor that had been...
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Influence of concentration on contact angle of water-Cu nanofluid on glass substrate
PublikacjaIn the paper the results of an experimental investigation of influence of nanoparticle concentration on contact angle of water-Cu nanofluid on glass substrate have been presented. Nanoparticles were tested at the concentration of 0.01%, 0.1%, and 1% by weight. In the present study copper was applied as nanoparticle while distilled, deionized water was used as a base fluid. The mean diameter of nanoparticle is estimated to be 50...
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MODAL ANALYSIS OF REAL TIMBER FRAME HOUSES WITH DIFFERENT INSULATION MATERIALS
PublikacjaThe aim of this article is to present the results of a numerical modal analysis of two actual structures of timber frame buildings and the different behaviour due to the used insulation material. One model of the timber structure was filled with mineral wool, while the other with polyurethane foam. During the modal analysis, eigenvalues for both models have been determined. The results of the analysis clearly show the increase...
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Technical evaluation of marine auxiliary diesel engine on the basis of parameters synchronous generator
PublikacjaThe article presents a method for evaluating the technical condition of selected structural elements of the reciprocating internal combustion engine driving a synchronous generator. Th results of measurements of the electric generator parameters are the diagnostic information source. On this basis it is possible to determine the instantaneous angular speed marine engine crankshaft which, in turn, is the basis for reasoning about...