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Search results for: TWO-PHASE FLOW MULTIPLIER
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Desirability-based optimization of dual-fuel diesel engine using acetylene as an alternative fuel
Publicationhe study examined the dual-fuel engine performance employing acetylene gas as primary fuel and diesel as pilot fuel. The engine's operational parameters were adjusted using the Box-Behnken design, and the results were recorded. The best operating settings were yielded as 81.25 % engine load, 4.48 lpm acetylene gas flow rate and the compression ratio were 18. At this optimized setting the BTE was 27.1 % and the engine emitted 360...
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BADANIE WPŁYWU INDUKCJI REMANENCJI NA STAN PRZEJŚCIOWY JEDNOFAZOWEGO UKŁADU TRANSFORMATOROWEGO
PublicationW referacie przedstawiono wyniki badań eksperymentalnych i symulacyjnych wpływu indukcji remanencji w rdzeniu transformatora jednofazowego na jego stan przejściowy przy jego pracy jałowej. Badany obiekt jest układem transformatorowym o dwóch uzwojeniach nawiniętych na zwijanym z blachy anizotropowej rdzeniu w kształcie toroidu. Doświadczenia eksperymentalne polegały na rozładowywaniu kondensatora przez uzwojenie strony pierwotnej...
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Wielkie wydarzenia jako katalizator procesów rewitalizacji
PublicationCelem referatu jest naświetlenie procesów rewitalizacji towarzyszących organizacji wielkich wydarzeń w dwóch aspektach: 1) rewitalizacja jako motor lub jako skutek działań; 2) lokalność i regionalność procesów rewitalizacji. Omówieniu tych zjawisk służą przykłady miast-organizatorów wielkich wydarzeń, Sydney (IO 2000), Pekin (IO 2008), Londyn (IO 2012) oraz Gdańsk (Euro 2012) i Szczecin (The Tall Ships Races 2013). Kluczową kwestią...
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The structure of strontium–borate glasses and glass-ceramics containing bismuth and vanadium oxides measured with X-ray diffraction method
Open Research DataThe structure of strontium–borate glasses and glass-ceramics containing bismuth and vanadium oxides was measured by XRD.
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The structure of strontium–borate glass-ceramics containing crystalites of Bi2VO5.5. measured with X-ray diffraction and SEM methods
Open Research DataThe structure of strontium–borate glass-ceramics containing Bi2VO5.5 crystallites was measured by XRD and SEM.
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Effect of the ionic liquids on extraction of aromatic and sulfur compounds from the model petrochemical stream
PublicationSuitability of a imidazolium ionic liquids (ILs) as solvents in dearomatization and desulfurization in the ternary systems and in a model multicomponent systems has been analyzed. With this aim, ternary liquid-liquid phase equilibrium data (LLE) have been obtained for ternary mixtures of {IL + benzene, or toluene, or thiophene, or 2-butanethiol + hexane}, or {IL + benzene + 2-methylpentane} at T = 298.15 K and ambient pressure,...
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Closed-Loop Control System Design for Wireless Charging of Low-Voltage EV Batteries with Time-Delay Constraints
PublicationThis paper presents an inductive power transfer system on the basis of a double single- phase three-level T-type inverter and two split transmitting coils for constant current and constant voltage wireless charging of low-voltage light electric vehicle batteries with closed-loop control, considering time-delay communication constraints. An optimal control structure and a modified control strategy were chosen and implemented to...
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Inhibitory and antimicrobial activities of OGTI and HV-BBI peptides, fragments and analogs derived from amphibian skin
PublicationA series of linear and cyclic fragments and analogs of two peptides (OGTI and HV-BBI) isolated from skin secretions of frogs were synthesized by the solid-phase method. Their inhibitory activity against several serine proteinases: bovine beta-trypsin, bovine alpha-chymotypsin, human leukocyte elastase and cathepsin G from human neutrophils, was investigated together with evaluation of their antimicrobial activities against Gram-negative...
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Switched-capacitor DC-DC converters in arbitrary switching mode - topologically derived resistive models based on incremental graph approach.
PublicationIn the preceding paper we reviewed some of modeling approaches aimed at systematic formulation and solution of switched capacitor DC-DC converters. In our review, special attention was paid to computationally efficient and mathematically elegant methods. In so doing we had tried to demonstrate the virtues of unified Incremental Graph (IG) approach. Incremental Graph is, in concept, a tool originally created for analysis and synthesis...
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A biochemical multi-species quality model of a drinking water distribution system for simulation and design
PublicationDrinking Water Distribution Systems (DWDSs) play a key role in sustainable development of modern society. They are classified as critical infrastructure systems. This imposes a large set of highly demanding requirements on the DWDS operation and requires dedicated algorithms for on-line monitoring and control to tackle related problems. Requirements on DWDS availability restrict the usability of the real plant in the design phase....
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Heat transfer enhancement of modular thermal energy storage unit for reversible heat pump cooperation
PublicationThe following article presents experimental comparison research on a hexagonal shelland-tube latent thermal energy storage (TES). Such shape of a shell was deliberately chosen instead of a cylindrical one due to its high modularity and with intent for future applications in automobiles (EV and PHEV) air conditioning systems (HVAC). Two geometries of helical coils, acting as tubes, were studied in this article. One was a simple...
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Increasing the Utilization of dc-link Voltage of a Five-Leg VSI Based on Rotor Angle Control of Dual Induction Motors
PublicationThis paper introduces an increased utilization of the dc-link voltage of a five-leg voltage source inverter (VSI) based on the rotor flux angle control technique for dual induction motors, IM. The main purpose is to utilize additional abilities provided by a multi-motor drive system in limited operating conditions. Generally, a multi-motor drive system is widely used in electric vehicles (EVs), traction systems and in several industrial...
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Perfusion computed tomography: 4 cmversus8 cm coverage size in subjects with chronic carotid artery stenosis
PublicationOBJECTIVE: The impact of coverage size on global cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT) and time to peak (TTP) parameters has not been investigated in patients with chronic carotid artery stenosis. METHODS: 63 patients with stenosis of >70% within a single internal carotid artery and neurological symptoms were randomly assigned to two well-matched groups. Differences in CT perfusion scan...
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The influence of Nigella sativa essential oil on proliferation, activation, and apoptosis of human T lymphocytes in vitro
PublicationIn previous work, we tested the immunomodulatory effect of Nigella sativa (NS) fatty oil. Our results demonstrated that unrefined, obtained by cold pressing black cumin seed oil inhibited lymphocytes’ proliferation and induced their apoptosis in a dose-dependent manner. In this study, we examined the immunomodulatory properties of essential oil (EO) obtained from the NS seeds by hydrodistillation and its two main constituents:...
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The protocol for using elastic wall model in modeling blood flow within human artery
PublicationMedical diagnostic tools will play a major role in the future for an effective patient treatment and reduction their mortality, related to the cardiovascular system diseases (CVDs). There is an urgent need for developing diagnostic procedure to be robust, reliable, accurate and efficient, in the framework of a paradigm shift. Application of numerical techniques is seen as a perspective tool for such purpose. Nevertheless, existing...
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Biomass-Derived Nitrogen Functionalized Carbon Nanodots and Their Anti-Biofouling Properties
PublicationThe prevalence of the antibiotic resistant bacteria remains a global issue. Cheap, sustainable and multifunctional antibacterial membranes are at the forefront of filtrating materials capable of treating multiple flow streams, such as water cleansing treatments. Carbon nanomaterials are particularly interesting objects shown to enhance antibacterial properties of composite materials. In this article, amino-functionalized, photoluminescent...
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Identification of Parameters Influencing the Accuracy of the Solution of the Nonlinear Muskingum Equation
PublicationTwo nonlinear versions of the Muskingum equation are considered. The difference between both equations relates to the exponent parameter. In the first version, commonly used in hydrology, this parameter is considered as free, while in the second version, it takes a value resulting from the kinematic wave theory. Consequently, the first version of the equation is dimensionally inconsistent, whereas the proposed second one is consistent. It...
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Reservoir Influence on Pressure Wave Propagation in Steel Pipes
PublicationThe relation between the length of steel pipe and the pressure wave period in the system, reservoir-pipe-valve, is discussed. Experiments carried out for the short steel pipes showed that in such a system, the pressure wave celerity estimated using the measured wave cycles systematically increases with the increase of the pipe length. The observed differences can exceed even 90 m=s. As the pressure wave traveling in the pipe with...
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Experimental and numerical analysis of the pyrolysis dynamics of a single wood particle: presentation of the radiographic technique
PublicationPyrolysis is an oxygen-free process for the thermal decomposition of raw materials. The heat conduction and flow of pyrolysis products (i.e., the gas fraction and liquid vapour generated during pyrolysis) influence the process and products. In this work, the influence of the orientation of wooden particle fibres with respect to the direction of the heat source on the dynamics of the process was investigated, where there were two...
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Comparison of the Effects of Conventional and Alternative External Carbon Sources for Enhancing of the Denitrification Process
PublicationFood industry effluents are considered a potential alternative for methanol when seeking external carbon sources to enhance denitrification in municipal wastewater treatment plants (WWTPs). The aim of this study was to determine the immediate effects of dosing different carbon sources on the denitrification capability of process biomass from the "Wschod" WWTP in Gdansk (northern Poland). Five carbon sources, including settled wastewater,...
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Barium boron aluminum silicate glass system for solid state optical gas sensors
PublicationRecent increasing demand for new eco-friendly materials and for low cost fabrication process for use in optical sensors field, raise concern about alternative materials for this application. We have designed two glass-ceramics compositions from the quaternary ROAl2O3- SiO2-B2O3(R=Ba) alkali-earth aluminum silicate system, labeled B72 and B69, with high refractive index (>1.6), large values of Abbe number (94.0 and 53.0, respectively),...
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The effect of boron concentration on the electrical, morphological and optical properties of boron-doped nanocrystalline diamond sheets: Tuning the diamond-on-graphene vertical junction
PublicationIn this paper, the effect of boron doping on the electrical, morphological and structural properties of free-standing nanocrystalline diamond sheets (thickness ~ 1 μm) was investigated. For this purpose, we used diamond films delaminated from a mirror-polished tantalum substrate following a microwave plasma-assisted chemical vapor deposition process, each grown with a different [B]/[C] ratio (up to 20,000 ppm) in the gas phase....
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EXTRAORDINARY RAINFALLS IN GDANSK (NORTHERN POLAND) IN THE 21ST CENTURY
PublicationIn the 21st century Gdansk had been affected by two rainfall events with a total precipitation amount of over 120 mm each. Rainfall parameters exceeded the regional values of the rain occurring once every 100 years. At the meteorological station of Gdansk University of Technology, July 9th 2001 was recorded 123.5 mm and July 14th 2016, 150.8 mm rainfall (within 24 hours observation period). Despite the same seasons of summer months...
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Composite as a Material of the Future in the Era of Green Deal Implementation Strategies
PublicationComposite materials have become synonymous with modernity, desired in nearly every aspect of our daily lives, from simple everyday objects to sanitary facilities, pipelines, the construction of modern sewer networks, their renovation, water supply, and storage reservoirs, to complex structures—automotive, planes, and space science. Composites have seen a considerable rise in attention owing to their characteristics, durability,...
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Real-time monitoring of the emission of volatile organic compounds from polylactide 3D printing filaments
PublicationEstablishing the emission profile of volatile organic compounds generated during fused deposition modeling 3D printing using polymer filaments is important in terms of both understanding the processes taking place during thermal degradation of thermoplastics, and assessing the user's exposure to potentially harmful volatiles. However, obtaining detailed, real-time qualitative and quantitative results poses a challenge. In this...
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Boron-Doped Diamond/GaN Heterojunction—The Influence of the Low-Temperature Deposition
PublicationWe report a method of growing a boron-doped diamond film by plasma-assisted chemical vapour deposition utilizing a pre-treatment of GaN substrate to give a high density of nucleation. CVD diamond was deposited on GaN substrate grown epitaxially via the molecular-beam epitaxy process. To obtain a continuous diamond film with the presence of well-developed grains, the GaN substrates are exposed to hydrogen plasma prior to deposition....
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Current Trends in Wick Structure Construction in Loop Heat Pipes Applications: A Review
PublicationThermal control systems have been introduced as an important part of electronic devices, enabling thermal management of their electronic components. Loop heat pipe (LHP) is a passive two-phase heat transfer device with significant potential for numerous applications, such as aerospace applications, high-power LEDs, and solar central receivers. Its advantages are high heat transfer capability, low thermal resistance, long-distance...
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Process Control of Biogas Purification Using Electronic Nose
PublicationNowadays, biogas produced from landfills and wastewater treatment plants or lignocellulosic biomass is important sustainable and affordable source of energy. Impurities from biogas stream can cause a serious odor problem, especially for residents of areas immediately adjacent to production plants. Therefore, biogas pre-treatment is necessary to protect engines that convert biogas into energy and in order to increase the specific...
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Comparative Study of Taste Substance Sensing by Liquid Membrane Oscillator and Electrochemical Systems With All-Solid-State Electrodes
PublicationIn food industry, different types of sensors are used for characterizing and quantifying taste substances. Therefore, it is important to establish the principal advantages and disadvantages of these sensors for optimal application. In this paper, two possible systems are compared for sensing the four fundamental tastes: sour (citric acid), salty (sodium chloride), sweet (sucrose), and bitter (caffeine or quinine hydrochloride). One...
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Experimental investigation on heat pipes supported by soy wax and lauric acid for electronics cooling
PublicationThis paper presents an experimental study of heat pipes for electronics cooling that were supported by energy storage materials (i.e. phase change materials - PCMs) coated at the adiabatic section. The PCMs utilized included two materials, namely lauric acid and soy wax, the latter being considered as a more cost-effective alternative. The study focused on three different powers: 20 W, 25 W, and 30 W. Both heating, cooling, and...
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Effect of Particle Size of Fly Ash Microspheres (FAMs) on the Selected Properties of Concrete
PublicationThis paper presents the investigations of selected properties of concrete containing two fractions of fly ash microspheres (FAMs) with grain size up to 200 μm and up to 500 μm. Concrete mixtures with ordinary Portland cement and three substitution rates of cement by FAMs, 1.3%, 2.0%, and 2.6%, were investigated. For all concrete mixes, the constant water–binder ratio (w/b) equal to 0.50 was used. The research program included the...
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Hybridized PWM Strategy for Three- and Multiphase Three-Level NPC Inverters
PublicationA simple hybridized pulsewidth modulation (PWM) algorithm for three- and multiphase three-level neutral point clamped (NPC) inverters is proposed. The proposed solution is based on classical space vector PWM (SVPWM) algorithms for two-level inverters but can also be based on sinusoidal PWM with min–max injection. An additional level of output voltage is obtained by modifying the resulting switching patterns taking into account...
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Multi-objective optimization of the cavitation generation unit structure of an advanced rotational hydrodynamic cavitation reactor
PublicationHydrodynamic cavitation (HC) has been widely considered a promising technique for industrial-scale process intensifications. The effectiveness of HC is determined by the performance of hydrodynamic cavitation reactors (HCRs). The advanced rotational HCRs (ARHCRs) proposed recently have shown superior performance in various applications, while the research on the structural optimization is still absent. The present study, for the...
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The Influence of Loop Heat Pipe Evaporator Porous Structure Parameters and Charge on Its Effectiveness for Ethanol and Water as Working Fluids
PublicationAbstract: This paper presents the results of experiments carried out on a specially designed experimental rig designed for the study of capillary pressure generated in the Loop Heat Pipe (LHP) evaporator. The commercially available porous structure made of sintered stainless steel constitutes the wick. Three different geometries of the porous wicks were tested, featuring the pore radius of 1, 3 and 7 um. Ethanol and water as two...
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Prediction of energy consumption and evaluation of affecting factors in a full-scale WWTP using a machine learning approach
PublicationTreatment of municipal wastewater to meet the stringent effluent quality standards is an energy-intensive process and the main contributor to the costs of wastewater treatment plants (WWTPs). Analysis and prediction of energy consumption (EC) are essential in designing and operating sustainable energy-saving WWTPs. In this study, the effect of wastewater, hydraulic, and climate-based parameters on the daily consumption of EC by...
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Variable-fidelity shape optimization of dual-rotor wind turbines
PublicationPurpose Dual-rotor wind turbines (DRWTs) are a novel type of wind turbines that can capture more power than their single-rotor counterparts. Because their surrounding flow fields are complex, evaluating a DRWT design requires accurate predictive simulations, which incur high computational costs. Currently, there does not exist a design optimization framework for DRWTs. Since the design optimization of DRWTs requires numerous model...
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Compact High Efficiency and Zero-Emission Gas-Fired Power Plant with Oxy-Combustion and Carbon Capture
PublicationReduction of greenhouse gases emissions is a key challenge for the power generation industry, requiring the implementation of new designs and methods of electricity generation. This article presents a design solution for a novel thermodynamic cycle with two new devices—namely, a wet combustion chamber and a spray-ejector condenser. In the proposed cycle, high temperature occurs in the combustion chamber because of fuel combustion...
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Marine traffic risk modelling – an innovative approach and a case study
PublicationThis paper presents a model to analyse the risk of two common marine accidents: collision and grounding. Attention is focused on oil tankers since they pose the highest environmental risks. A case study in selected areas of the Gulf of Finland in ice-free conditions is presented. The model utilizes a formula for risk calculation that considers both the probability of an unwanted event and its consequences. The model can be decomposed...
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THREE-DIMENSIONAL numerical investigation of MHD nanofluid convective heat transfer inside a CUBIC porous container with corrugated bottom wall
PublicationSimultaneous use of porous media and nanofluid as a heat transfer improvement method has recently captivated a great deal of attention. The heat transfer and entropy production of the Cu-water nanofluid inside a cubic container with a heated bottom wavy wall and an elliptic inner cylinder were numerically analyzed in this study. The container is partitioned into two sections: the left side is filled with permeable media and...
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Reliability of nitrogen removal processes in multistage treatment wetlands receiving high-strength wastewater
Publicationreatment wetlands have been proved to be more effective than conventional treatment processes in case of high-strength wastewater containing high concentrations of ammonium nitrogen and recalcitrant organic matter. In this study nitrogen removal processes and reliability of nitrogen removal at two identical pilot-scale multistage treatment wetlands (MTWs) receiving real, non-synthetic wastewater were discussed. The wastewater discharged...
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Application of subsurface vertical flow constructed wetlands to reject water treatment in dairy wastewater treatment plant
PublicationThe paper presents the effects of applying subsurface vertical flow constructed wetlands (SS VF) for the treatment of reject water generated in the process of aerobic sewage sludge stabilization in the biggest dairy wastewater treatment plant (WWTP) in Poland. Two SS VF beds were built: bed (A) with 0.65 m depth and bed (B) with 1.0 m depth, planted with reeds. Beds were fed with reject water with hydraulic load of 0.1 m d-1 in...
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Hydraulic analysis of causes of washout of Gdynia-Orłowo seashore during the flood in the Kacza river estuary
PublicationIn July 2016 in the Three-city agglomeration a rainfall episode of over a day duration and 150 mm summary rainfall height, occurred. This situation, extreme as for Polish conditions, caused significant freshets in rivers and streams running into Gdansk Bay, the Baltic Sea, and serving as collectors of rainfall waters for the sea-coast towns. In many areas of the Three-city flood phenomena and overflows took place. The flood also...
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Super-resolved Thermal Imagery for High-accuracy Facial Areas Detection and Analysis
PublicationIn this study, we evaluate various Convolutional Neural Networks based Super-Resolution (SR) models to improve facial areas detection in thermal images. In particular, we analyze the influence of selected spatiotemporal properties of thermal image sequences on detection accuracy. For this purpose, a thermal face database was acquired for 40 volunteers. Contrary to most of existing thermal databases of faces, we publish our dataset...
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A framework for Air Quality Management Zones - Useful GIS-based tool for urban planning: Case studies in Antwerp and Gdańsk
PublicationThere is a growing recognition of the importance of proper urban design in the improvement of air flow and pollution dispersion and in reducing human exposure to air pollution. However, a limited number of studies have been published so far focusing on the development of standard procedures which could be applied by urban planners to effectively evaluate urban conditions with respect to air quality. To fill this gap, a new approach...
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Temperature Evolution, Material Flow, and Resulting Mechanical Properties as a Function of Tool Geometry during Friction Stir Welding of AA6082
PublicationThe friction stir welding process was simulated for joining AA6082 aluminum alloy with the use of the computational fluid dynamics method. Two different tool geometries were used—a tapered cylindrical pin (simple pin) and a hexagonal pin with grooves (complex pin). The analysis of the simulations performed was discussed in terms of temperature evolution during the process, total heat input, residual stresses and material flow....
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Application of Feed Forward Neural Networks for Modeling of Heat Transfer Coefficient During Flow Condensation for Low and High Values of Saturation Temperatur
PublicationMost of the literature models for condensation heat transfer prediction are based on specific experimental parameters and are not general in nature for applications to fluids and non-experimental thermodynamic conditions. Nearly all correlations are created to predict data in normal HVAC conditions below 40°C. High temperature heat pumps operate at much higher parameters. This paper aims to create a general model for the calculation...
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Deterministic versus stochastic modelling of unsaturated flow in a sandy field soil based on dual tracer breakthrough data
PublicationThe 216 km2 Neuenhagen Millcreeck catchment can be characterized as a drought sensitive landscape in NE Germany. It is therefore a fundamental human interest to understand how water that fell as precipitation moves through the unsaturated soils and recharges groundwater. Additionally, a better knowledge of nutrient transport from soil to groundwater is important also, especially in landscapes with light sandy soils. For a better...
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Interactions of selected mono- and disaccharides with precipitated calcium carbonate particles
PublicationCalcium carbonate is a widespread compound in nature and it can be produced by living organisms in the biomineralization process. Calcite, aragonite and vaterite are anhydrous polymorphic forms of calcium carbonate, wherein the calcite is the most thermodynamically stable. Vaterite is the metastable crystalline phase, which can be a precursor of calcite and aragonite, because it can easily transformed by dissolution and re crystallization...
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Low-Cost and Precise Automated Re-Design of Antenna Structures Using Interleaved Geometry Scaling and Gradient-Based Optimization
PublicationDesign of contemporary antennas is an intricate endeavor involving multiple stages, among others, tuning of geometry parameters. In particular, re-designing antennas to different operating frequencies, makes parametric optimization imperative to ensure the best achievable system performance. If the center frequency at the current design is distant from the target one, local tuning methods generally fail, whereas global algorithms...
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Modelling of Different Aeration Modes Influencing Processes in SBR Bioreactor
PublicationCurrently, computer modelling together with the simulation tools tailored for that purpose constitute a very important element in planning technological changes within wastewater treatment plant. From the point of view of the WWTP operator every modification should be introduced in order to improve the quality of treated sewage with the lowest financial outlays. These requirements can be met by using computer programmes to effectuate...