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N-doped mesoporous carbon nanosheets obtained by pyrolysis of a chitosan–melamine mixture for the oxygen reduction reaction in alkaline media.
PublikacjaBy simple thermal decomposition of low-cost precursors (chitosan, melamine) in an inert atmosphere, nitrogen-doped porous carbonaceous materials were prepared. The samples pyrolyzed at 700 C are composed of mainly mesoporous nitrogen-doped carbon nanosheets and partially graphitized carbon. The nanosheets contain a disordered area due to the strain imposed by the presence of nitrogen and/or oxygen groups in their structure. Some...
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Methods for physical impairment constrained routing with selected protection in all-optical networks
PublikacjaIn this paper, we investigate the problem of survivable all-optical routing in WDM networks with physical impairments. One of the recent key issues in survivable optical network design refers to maximization of the ratio of routeable demands while keeping the overall network cost low. In WDM networks, this goal can be achieved by routing as many demands in all-optical way as possible. Based on the latest technical trends driven...
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Local-Global Space Mapping for Rapid EM-Driven Design of Compact RF Structures
PublikacjaIn this work, we introduce a robust and efficient technique for rapid design of compact RF circuits. Our approach exploits two-level space mapping (SM) correction of an equivalent circuit model of the structure under design. The first SM layer (local correction) is utilized to ensure good matching between the equivalent circuit and the electromagnetic model at the component level. On the other hand, the global correction allows...
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Design Space Reduction for Expedited Multi-Objective Design Optimization of Antennas in Highly-Dimensional Spaces
PublikacjaA surrogate-based technique for efficient multi-objective antenna optimization is discussed. Our approach exploits response surface approximation (RSA) model constructed from low-fidelity antenna model data (here, obtained through coarse-discretization electromagnetic simulations). The RSA model enables fast determination of the best available trade-offs between conflicting design goals. The cost of RSA model construction for multi-parameter...
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Quasi-Global Optimization of Antenna Structures Using Principal Components and Affine Subspace-Spanned Surrogates
PublikacjaParametric optimization is a mandatory step in the design of contemporary antenna structures. Conceptual development can only provide rough initial designs that have to be further tuned, often extensively. Given the topological complexity of modern antennas, the design closure necessarily involves full-wave electromagnetic (EM) simulations and—in many cases—global search procedures. Both factors make antenna optimization a computationally...
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Kriging metamodels and design re‐utilization for fast parameter tuning of antenna structures
PublikacjaThe paper addresses the problem of computationally efficient electromagnetic (EM)‐driven design closure of antenna structures. The foundations of the presented approach are fast kriging interpolation metamodels, utilized for two purposes: (a) producing a good starting point for further parameter tuning, and (b) yielding a reasonable Jacobian matrix estimate to jump‐start the optimization procedure. The models are rendered using...
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Chemical surface etching methods for ground tire rubber as sustainable approach for environmentally-friendly composites development– a review
PublikacjaGround tire rubber (GTR) has been used as a sustainable low-cost modifier in various composites. However, due to the hydrophobic nature of GTR, it is in compatible with most matrices and results in deterioration in both mechanical and physical properties of composites. This necessitates pre-modification of the powdered rubber to improve the interfacial bonding at the rubber-matric interface. The most common GTR modification research...
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Numerical analysis of CO2-water separation in a horizontal double T-junction
PublikacjaCarbon dioxide is considered one of the main factors leading to global warming. Considering the significant impacts of CO2 on climate change, various technologies have been developed in recent decades to control carbon emission, such as for example CO2 capture and storage. The developed cycle of a negative CO2 emission power plant includes some devices, out of which, separator plays an indispensable role. To this end, T-junction...
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Preparation and Properties of Thermoplastic Polyurethane Composites Filled with Powdered Buckwheat Husks
PublikacjaBio-based fillers for the polymer composites are still interesting from the scientific and industrial point of view, due to their low cost and renewable nature. In this work partially green composites were obtained by the mixing of thermoplastic poly(ester-urethane) with the unmodified and modified (by acetylation) grinded buckwheat husks. Obtained biocomposites were characterized in the terms of their chemical structure (FTIR),...
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Advanced operating methods
PublikacjaSelected operating methods of resistive gas sensors were presented. The methods utilize flicker noise (1/f noise), which gives additional information about ambient gas when compared with the recorded changes of DC resistance only. Methods of flicker noise measurements were outlined. Recently developed prototype gas sensors comprising golden nanoparticle functionalized with organic ligands can generate intense flicker noise induced...
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Globalized Knowledge-Based Simulation-Driven Antenna Miniaturization Using Domain-Confined Surrogates and Dimensionality Reduction
PublikacjaDesign of contemporary antenna systems encounters multifold challenges, one of which is a limited size. Compact antennas are indispensable for the new fields of application such as inter-net of things or 5G/6G mobile communication. Still, miniaturization generally undermines elec-trical and field performance. When attempted through numerical optimization, it turns into a constrained problem with costly constraints requiring electromagnetic...
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User Authentication by Eye Movement Features Employing SVM and XGBoost Classifiers
PublikacjaDevices capable of tracking the user’s gaze have become significantly more affordable over the past few years, thus broadening their application, including in-home and office computers and various customer service equipment. Although such devices have comparatively low operating frequencies and limited resolution, they are sufficient to supplement or replace classic input interfaces, such as the keyboard and mouse. The biometric...
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Superhydrophobic and superoleophilic melamine sponges impregnated with deep eutectic solvents for oil spill cleanup
PublikacjaThe extensive extraction of oil from the bottom of seas and oceans and its transportation by tankers increase the risk of potential environmental disasters associated with hydrocarbon fractions entering water reservoirs. Therefore, this paper presents the preparation of a simple impregnation of a melamine sponge with deep eutectic solvents (DES), which can be obtained from natural sources, including coconut oil, palm kernel oil,...
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DUAL CONSTELLATION GPS/GALILEO MOBILE SYSTEM FOR IMPROVING NAVIGATION OF THE VISUALLY IMPAIRED IN AN URBAN AREA
PublikacjaIt is well known by users of Portable Navigation Device (PND) and other GPS-based devices that positioning suffers from (local) significant decreases of accuracy in partially obscured environments like urbanized areas, where buildings (especially high buildings), trees or terrain block large portions of the sky. In such areas, GPS receiver performance is usually deteriorated by the reduced number of currently available satellite...
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Ultrasound-assisted solvent extraction of porous membrane packed solid samples: A new approach for extraction of target analytes from solid samples
PublikacjaFor the first time, a porous membrane-based method is proposed for the extraction of target analytes directly from the solid samples. This method involves the packing of solid sample inside a porous polypropylene membrane sheet whose edges are heat-sealed to fabricate a bag. This bag is immersed in a suitable solvent and the analytes are extracted by the application of ultrasound energy. The various factors that affect the extraction...
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DESIGN OF THE DUAL CONSTELLATION GPS/GALILEO MOBILE DEVICE FOR IMPROVING NAVIGATION OF THE VISUALLY IMPAIRED IN AN URBAN AREA
PublikacjaIt is well known by users of Personal Navigation Device (PND) and other GPS-based devices that positioning suffers from (local) significant decreases of accuracy in partially obscured environments like urbanized areas, where buildings (especially high buildings), trees or terrain block large portions of the sky. In such areas, GPS receiver performance is usually deteriorated by the reduced number of currently available satellite...
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A new cold-adapted beta-D-galactosidase from the Antarctic Arthrobacter sp. 32c - gene cloning, overexpression, purification and properties
PublikacjaThe development of a new cold-active β-D-galactosidases and microorganisms that efficiently ferment lactose is of high biotechnological interest, particularly for lactose removal in milk and dairy products at low temperatures and for cheese whey bioremediation processes with simultaneous bio-ethanol production. In this article, we present a new β-D-galactosidase as a candidate to be applied in the above mentioned biotechnological...
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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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Improved-Efficacy EM-Driven Optimization of Antenna Structures Using Adaptive Design Specifications and Variable-Resolution Models
PublikacjaOptimization-driven parameter tuning is an essential step in the design of antenna systems. Although in many cases it is still conducted through parametric studies, rigorous numerical methods become a necessity if truly optimum designs are sought for, and the problem intricacies (number of variables, multiple goals, constraints) make the interactive approaches insufficient. The two practical considerations of electromagnetic (EM)-driven...
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Expedited Machine-Learning-Based Global Design Optimization of Antenna Systems Using Response Features and Multi-Fidelity EM Analysis
PublikacjaThe design of antenna systems poses a significant challenge due to stringent per-formance requirements dictated by contemporary applications and the high com-putational costs associated with models, particularly full-wave electromagnetic (EM) analysis. Presently, EM simulation plays a crucial role in all design phases, encompassing topology development, parametric studies, and the final adjustment of antenna dimensions. The latter...
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Novel Complementary Resonator for Dielectric Characterization of Substrates Based on Permittivity and Thickness
PublikacjaThis paper presents a novel complementary resonator featuring high sensitivity, low fabrication cost, and improved performance. The proposed structure consists of a complementary concentric square and circular ring resonator (CCSCRR) with multiple splits to enhance the inductance of the resonator. The proposed CCSCRR is coupled to a microstrip transmission line with an impedance of fifty ohms to create a high-sensitivity sensor....
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Application of cyanated asphaltenes in gas-phase adsorption processes for removal of volatile organic compounds
PublikacjaThe paper presents an innovative, chemically modified (methylcyanated) asphaltene-based adsorbent that can be an inter-esting low-cost alternative for traditional adsorbents. Adsorption properties of adsorbents were examined by inverse gas chromatography technique, adsorption isotherms, and breakthrough curves. A significant increase in retention volume for pyridine, 2-pentanone, nitropropane, toluene, and 1-butanol was observed....
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Predicting Performance of Lightweight Concrete with Granulated Expanded Glass and Ash Aggregate by Means of Using Artificial Neural Networks
PublikacjaLightweight concrete (LWC) is a group of cement composites of the defined physical, mechanical, and chemical performance. The methods of designing the composition of LWC with the assumed density and compressive strength are used most commonly. The purpose of using LWC is the reduction of the structure’s weight, as well as the reduction of thermal conductivity index. The highest possible strength, durability and low thermal conductivity...
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Nanostructure of the laser-modified transition metal nanocomposites for water splitting
PublikacjaAlthough hydrogen is considered by many to be the green fuel of the future, nowadays it is primarily produced through steam reforming, which is a process far from ecological. Therefore, emphasis is being put on the development of electrodes capable of the efficient production of hydrogen and oxygen from water. To make the green alternative possible, the solution should be cost-efficient and well processable, generating less waste...
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Fast tolerance-aware design optimization of miniaturized microstrip couplers using variable-fidelity EM simulations and re-sponse features
PublikacjaManufacturing tolerances and other types of uncertainties may considerably affect operation and performance of microwave components and systems. Quantification of these effects is therefore an important part of the design process. It is even more important to obtain designs whose sensitivity to parameter deviations is reduced as much as possible. All of these require statistical analysis carried out at the level of electromagnetic...
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Optimizing FSO networks resilient to adverse weather conditions by means of enhanced uncertainty sets
PublikacjaThis work deals with dimensioning of wireless mesh networks (WMN) composed of FSO (free space optics) links. Although FSO links realize broadband transmission at low cost, their drawback is sensitivity to adverse weather conditions causing transmission degradation on multiple links. Hence, designing such FSO networks requires an optimization model to find the cheapest configuration of link capacities that will be able to carry...
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Context of Digitalized Employment for Older Adults with Autism Spectrum Disorder in the New Normal
PublikacjaEmployers are actively considering how to normalize remote work technology across different industries. The residual risk of coronavirus disease-19 (COVID-19) will necessarily lower the bar for allowing some workers to stay remote on a more permanent basis. This is based on the realization that many essential jobs can be teleworked while retaining or enhancing productivity. The decisions employers make regarding future work arrangements...
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Two-Stage Variable-Fidelity Modeling of Antennas with Domain Confinement
PublikacjaSurrogate modeling has become the method of choice in solving an increasing number of antenna design tasks, especially those involving expensive full-wave electromagnetic (EM) simulations. Notwithstanding, the curse of dimensionality considerably affects conventional metamodeling methods, and their capability to efficiently handle nonlinear antenna characteristics over broad ranges of the system parameters is limited. Performance-driven...
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Tubular House - Form Follows Technology, Concrete Shell Structure with Inner Thermal Insulation
PublikacjaThe aim of this paper is the theoretical analysis of the possibilities and limitations of using an unconventional technology and the original architectural form stemming from it – the building with external construction and internal insulation. In Central European climatic conditions, the traditional solution for the walls of heated buildings relies on using external thermal insulation. This stems from building physics: it prevents...
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Composite as a Material of the Future in the Era of Green Deal Implementation Strategies
PublikacjaComposite 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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Time for temporariness! Temporary architecture - whim or necessity?
PublikacjaWhat are the qualities of temporary architectural objects that make them helpful instruments for evolving the image of contemporary urban space? Six hypotheses provide rationales for why current temporary architecture seems to be a remedy for dysfunctional city structures. The research was limited to the temporary architectural objects constructed in open-air city zones, including the architecture of events. The temporary objects'...
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Resonator-Loaded Waveguide Notch Filters with Broad Tuning Range and Additive-Manufacturing-Based Operating Frequency Adjustment Procedure
PublikacjaThis article presents a new class of ring-resonator-loaded waveguide notch filters with a broad tuning range, low cost, and improved performance. The proposed approach employs a comple-mentary asymmetric split ring resonator coupled to a microstrip transmission line and excited in a rectangular waveguide. An equivalent circuit model is proposed to explain the working principle of the proposed notch filter. The adjustment of the...
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Rapid multi-criterial design of microwave components with robustness analysis by means of knowledge-based surrogates
PublikacjaManufacturing tolerances and uncertainties concerning material parameters, e.g., operating conditions or substrate permittivity are detrimental to characteristics of microwave components. The knowledge of relations between acceptable parameter deviations (not leading to violation of design specifications) and the nominal performance (not considering uncertainties), and is therefore indispensable. This paper proposes a multi-objective...
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New light on the photocatalytic performance of NH4V4O10 and its composite with rGO
PublikacjaSolar-driven photocatalysis has shown great potential as a sustainable wastewater treatment technology that utilizes clean solar energy for pollutant degradation. Consequently, much attention is being paid to the development of new, efficient and low-cost photocatalyst materials. In this study, we report the photocatalytic activity of NH4V4O10 (NVO) and its composite with rGO (NVO/rGO). Samples were synthesized via a facile one-pot...
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Shape Memory Alloy-Based Fluidically Reconfigurable Metasurfaced Beam Steering Antenna
PublikacjaA low-cost actuator-based fluidically programmable metasurface (FPMS) antenna is proposed to solve the slow tuning speed problem of the manually fluidic based reconfigurable antennas. The FPMS-based antenna is probe-fed and comprises a 4 × 4 square ring metasurface as a superstrate. Moreover, two shape memory alloy (SMA)-based electrically-controlled actuators are employed in the design for controlling the position of the 3D-printed...
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Effects of the Covid-19 travel restrictions on metropolises mobility: empirical evidence from the Tricity metropolis (Poland)
PublikacjaThis paper aims to assess changes in mobility and modal shift caused by COVID-19 travel restrictions among the residents of Gdańsk Bay Metropolis (Poland). Measurement’s moments were assumed in periods differing in the level of restric- tions. The computer-assisted telephone interview (CATI) was carried out in November and December 2020. The results did not confirm the expected modal shift. However, significant changes in the number...
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Rapid assessment of the authenticity of limequat fruit using the electronic nose and gas chromatography coupled with mass spectrometry
PublikacjaCitrus fruits are very popular food products. There are many species and varieties of them. There are also documented cases of some citrus fruits causing a severe allergic reaction. Some species of the citrus fruits, especially hybrid ones show a reduced allergenic effect due to the lack of seeds. There is a need for rapid methods for evaluation of citrus’ botanical origin. During research, the headspace of three citrus fruits...
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Family Tree for Aqueous Organic Redox Couples for Redox Flow Battery Electrolytes: A Conceptual Review
PublikacjaRedox flow batteries (RFBs) are an increasingly attractive option for renewable energy storage, thus providing flexibility for the supply of electrical energy. In recent years, research in this type of battery storage has been shifted from metal-ion based electrolytes to soluble organic redox-active compounds. Aqueous-based organic electrolytes are considered as more promising electrolytes to achieve “green”, safe, and low-cost...
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Highly Reliable Passive RFID-Based Inductor–Capacitor Sensory System Strengthened by Solvatochromism for Fast and Wide-Range Lactate Detection
PublikacjaA passive radio frequency-identification-based inductor-capacitor (LC) lactate sensory system with a specific dye-containing interdigitated capacitor (IDC) in which the sensing signal is amplified by the solvatochromic effect is proposed. When a lactate solution contacts the IDC of the LC lactate sensor, the capacitance of the IDC changes, changing the resonance frequency of the sensor. This changes the oscillation frequency of...
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Ground tire rubber functionalization as a promising approach for the production of sustainable adsorbents of environmental pollutants
PublikacjaWaste tires management and further utilization are currently one of the biggest concerns regarding the environment and human health protection. At present, shredding, grinding, or pulverization of waste tires are the most popular options for industrial recycling. Although many solutions for ground tire rubber (GTR) applications were checked and verified so far, their further implementation at an industrial scale is still very limited....
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Rapid on-line method of wastewater parameters estimation by electronic nose for control and operating wastewater treatment plants toward Green Deal implementation
PublikacjaIn order to comply with legal regulations related to wastewater quality, the operational mode of facilities at wastewater treatment plant (WWTP) should be properly adjusted according to parameters of influents, however it is very difficult without frequently performed measurements. Currently there are known many techniques and devices for assesment of wastewater parameters such as chemical oxygen demand, biochemical oxygen demand,...
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Highly effective asphaltene-derived adsorbents for gas phase removal of volatile organic compounds
PublikacjaA novel nitrated asphaltene-derived adsorbent (Asf-Nitro) was prepared using facile isolation and modification procedures. The successful modification was confirmed by Fourier-transform infrared spectroscopy (FTIR). The nitrated adsorbent was evaluated in terms of dispersive and specific interactions, Lewis acid-base properties and adsorption isotherms by means of inverse gas chromatography (IGC). Nitration was found to be extremely...
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High-Efficacy Global Optimization of Antenna Structures by Means of Simplex-Based Predictors
PublikacjaDesign of modern antenna systems has become highly dependent on computational tools, especially full-wave electromagnetic (EM) simulation models. EM analysis is capable of yielding accurate representation of antenna characteristics at the expense of considerable evaluation time. Consequently, execution of simulation-driven design procedures (optimization, statistical analysis, multi-criterial design) is severely hindered by the...
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Chapter 11 – Application of Chemical Sensors and Sensor Matrixes to Air Quality Evaluation
PublikacjaIndoor and outdoor air quality is one of the key factors influencing human health. However, air quality evaluation is not easy task. Air is a complex system, which is subjected to changes even within short period of time. Progress in analytical methods and analytical tools provides increasingly more reliable information on the condition and quality of indoor and outdoor air. This progress, however, generates an increase in the...
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Comparison of target strength (TS) distributions obtained by means of the use of direct and indirect techniques in sea cages
PublikacjaThe aim of this study is to verify the reliability of a processing application developed for the indirect measurement of target strength (TS), with a view to the integration into a single-beam system for its utilization in fish farms. Dorsal and ventral measurements are carried out for gilt-head sea-bream (Spams Aurata) for 5 size classes using a split-beam EK60 echosounder and single-beam data obtained from one of the channels...
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HILS for the Design of Three-Wheeled Mobile Platform Motion Surveillance System with a Use of Energy Performance Index
PublikacjaCurrent tendency in mechatronic design requires the use of comprehensive development of an environment, which gives the possibility to prototype, design, simulate and integrate with dedicated hardware. The paper discusses the Hardware-In-the-Loop Simulations (HILS) mechatronic technique, used during the design of the surveillance system based on energy performance index. The presented test configuration (physical controller – emulated...
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Economical methods for measuring road surface roughness
PublikacjaTwo low-cost methods of estimating the road surface condition are presented in the paper, the first one based on the use of accelerometers and the other on the analysis of images acquired from cameras installed in a vehicle. In the first method, miniature positioning and accelerometer sensors are used for evaluation of the road surface roughness. The device designed for installation in vehicles is composed of a GPS receiver and...
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SORPTION OF SELECTED CHLORINATED SOLVENTS ON PLANT DEBRIS COLLECTED IN A CITY PARK
PublikacjaDebris from deciduous trees in the form of park green waste was investigated as a potential biosorbent for the removal of chlorinated solvents from water. The sorption properties of beech leaves and cupules, oak leaves and acorns, birch leaves and lime leaves (all tree species common for a moderate climate) in a non-modified form were investigated with regard to the removal of perchloroethylene, 1,1,2-trichloroethane and 1,1,1,2-tetrachlorothane....
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Expedited antenna optimization with numerical derivatives and gradient change tracking
PublikacjaDesign automation has been playing an increasing role in the development of novel antenna structures for various applications. One of its aspects is electromagnetic (EM)-driven design closure, typically applied upon establishing the antenna topology, and aiming at adjustment of geometry parameters to boost the performance figures as much as possible. Parametric optimization is often realized using local methods given usually reasonable...
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Ultrasound-assisted heterogeneous activation of persulfate and peroxymonosulfate by asphaltenes for the degradation of BTEX in water
PublikacjaThis study investigated – for the first time - the simultaneous degradation of benzene, toluene, ethylbenzene and o-xylene (BTEX) by persulfate (PS) and peroxymonosulfate (PMS) activated by asphaltenes (Asph) under ultrasound (US) irradiation. Advantageous properties such as high thermal stability, low production cost and extensive availability make asphaltenes as an appealing carbonaceous material for heterogeneous catalysis....