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Air-cooled photovoltaic roof tile as an example of the BIPVT system – An experimental study on the energy and exergy performance
PublicationThe air-cooled photovoltaic tile is a subject of presented investigations, which focused on improving the overall system efficiency of PV tiles with heat recovery. The operational efficiency of a PV roof tile, together with the construction optimising the air cooling efficiency, were the main points of plans realized at this research stage. The article describes the experimental research consisting of the assessment of electrical,...
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Estimation of Broadband Complex Permeability Using SIW Cavity-Based Multimodal Approach
PublicationIn this article, an attractive multimodal substrate integrated waveguide (SIW) based methodology is presented for the characterization of magnetic materials in the broadband microwave frequency. The proposed approach employs a modified feed under-coupled SIW cavity instead of conventional feed over-coupled multiple SIW cavities; it uses the modified closedform expression, developed from the first principle to consider the effect...
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Methodology for implementing power plant efficiency standards for power generation: potential emission reduction
PublicationSome methods of generating power such as power generation through coal, natural gas, oil result in inevitable emissions of greenhouse gases. While power generation is necessary due to its increasing demand, it is important for power companies to generate their power in an efcient manner to reduce its efect on the environment. One of the most efective ways of tackling inefciency issues is through the implementation of efciency standard....
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Personal branding of artists and art-designers: necessity or desire?
PublicationPurpose Personal branding becomes a new in-demand skill for all professionals today. To be well-known helps to achieve success in the networked business environment. Personal relationships and a good reputation in the reality of network economy help young artists and art designers move up the career ladder. This paper aims to discuss a problem of artists who often find it difficult to define their artistic and self-distinction...
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ENVIRONMENTAL ASSESSMENT OF SOLAR CELL MATERIALS
PublicationIn today’s world, fossil fuels, including coal, oil, and gas, are the primary energy sources from which electricity is obtained. As they are exhaustible and their exploitation has a negative impact on the natural environment, they should be, at least partially, replaced by renewable energy sources. One of these sources is solar energy. The use of solar energy releases no CO2, SO2, or NO2 gases, and does not contribute to global...
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The occurrence of heavy metals and metal-resistant bacteria in water and bottom sediments of the Straszyn reservoir (Poland)
PublicationThe aim of this study is investigate the distribution of selected heavy metals (zinc, copper, lead, cadmium) and metal-resistant bacteria in water and bottom sediments of drinking water reservoir for Gdańsk (Poland). The research area - Straszyn Lake is a dam reservoir on Radunia river, of the total volume of 3 mln m3. Sediment and water sampling took place between May and October 2013 (eight series). Regarding metal concentration...
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Research on Tool Temperature Dependence on Lapping Grains Size
PublicationCommonly used as a finishing operation, lapping has been used for achieving ultra-high finishes and close tolerances between mating pieces. Its carried out by applying loose abrasive grains between work and lap surfaces, and causing a relative motion between them resulting in a finish of multi-directional lay. The grains activity (sliding and rolling) in the working gap causes not only the material removal but also the temperature...
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Diagnostic Analysis of Exhaust Gas with A Quick-Changing Temperature from a Marine Diesel Engine Part II / Two Factor Analysis
PublicationThe article presents a continuation of research carried out to determine the effect of input parameters (changes in engine structure parameters) on selected output parameters (diagnostic measures), based on quickly changing exhaust gas temperature. A method of determining the simultaneous influence of two input factors (the structure parameter and the engine load) on one output factor was presented, as well as an evaluation...
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Theoretical Encapsulation of Fluorouracil (5-FU) Anti-Cancer Chemotherapy Drug into Carbon Nanotubes (CNT) and Boron Nitride Nanotubes (BNNT)
PublicationIntroduction: Chemotherapy with anti-cancer drugs is considered the most common approach for killing cancer cells in the human body. However, some barriers such as toxicity and side effects would limit its usage. In this regard, nano-based drug delivery systems have emerged as cost-effective and efficient for sustained and targeted drug delivery. Nanotubes such as carbon nanotubes (CNT) and boron nitride nanotubes (BNNT) are promising...
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Prediction of maximum tensile stress in plain-weave composite laminates with interacting holes via stacked machine learning algorithms: A comparative study
PublicationPlain weave composite is a long-lasting type of fabric composite that is stable enough when being handled. Open-hole composites have been widely used in industry, though they have weak structural performance and complex design processes. An extensive number of material/geometry parameters have been utilized for designing these composites, thereby an efficient computational tool is essential for that purpose. Different Machine Learning...
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Estimation of the Regenerative Braking Process Efficiency in Electric Vehicles
PublicationIn electric and hybrid vehicles, it is possible to recover energy from the braking process and reuse it to drive the vehicle using the batteries installed on-board. In the conditions of city traffic, the energy dissipated in the braking process constitutes a very large share of the total resistance to vehicle motion. Efficient use of the energy from the braking process enables a significant reduction of fuel and electricity consumption...
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Ellipse-fitting algorithm implementation in the impedance measurement system based on DAQ card with FPGA
PublicationThe paper presents an implementation of the ellipse-fitting algorithm in the impedance measurement system based on DAQ card equipped with FPGA chip. The method implementation was tested by simulation means as well as experimentally in the designed and presented measurement system. Finally, the limit values of sampling parameters which assures satisfying accuracy were given.
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Luminescent collisions of He+ and He++ ions with H2 molecules at energies below 2 keV
PublicationSpectroscopic studies of collisions between He+ and He++ ions with H2 gas target have been performed in the 200–600nm wavelength range. Atomic lines of hydrogen Balmer series and several helium lines were identified and their excitation functions between 50 eV and 1keV (2keV for He++) were determined.
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Areas of Updraft Air Motion in an Idealised Weather Research and Forecasting Model Simulation of Atmospheric Boundary Layer Response to Different Floe Size Distributions
PublicationPresented dataset is part of a numerical modelling study focusing on the analysis of the influence of sea ice floe size distribution (FSD) on the horizontal and vertical structure of convection in the atmosphere. The total area and spatial arrangement of the up-drafts indicates that the FSD affects the total moisture content and the values of area averaged turbulent fluxes in the model domain. In fact, while convective updrafts...
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Convergence or divergence in the European Union
PublicationThe disparities in economic prosperity revealed both from inter-country and inter-region perspective are one of the main problem in the modern economy. They consist of the dispersion in the real values such as incomes, GDP or productivity, but also nominal values such as prices and costs. The European Union is aware of this problem hence the role of the regional and structural policy aiming enhancing the cohesion between member...
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A Reduction Method for Bathymetric Datasets that Preserves True Coastal Water Geodata
PublicationWater areas occupy over 70 percent of the Earth’s surface and are constantly subject to research and analysis. Often, hydrographic remote sensors are used for such research, which allow for the collection of information on the shape of the water area bottom and the objects located on it. Information about the quality and reliability of the depth data is important, especially during coastal modelling. In-shore areas are liable...
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Inverse and forward surrogate models for expedited design optimization of unequal-power-split patch couplers
PublicationIn the paper, a procedure for precise and expedited design optimization of unequal power split patchcouplers is proposed. Our methodology aims at identifying the coupler dimensions that correspond to thecircuit operating at the requested frequency and featuring a required power split. At the same time, thedesign process is supposed to be computationally efficient. The proposed methodology involves two typesof auxiliary models (surrogates):...
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High-temperature properties of titanium-substituted yttrium niobate
Publicationhe defect fluorite titanium-doped yttrium niobate samples Y3Nb1−xTixO7−δ have been synthesized and investigated by the means of high-temperature X-ray diffraction, dilatometry, and thermogravimetry. Thermal expansion coefficients (TECs) as well as chemical expansion coefficients for material with 5, 10, and 15 mol% of titanium were determined. All investigated samples exhibit chemical contraction caused by Ti doping. The values...
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Contamination of Arctic Lakes with Persistent Toxic PAH Substances in the NW Part of Wedel Jarlsberg Land (Bellsund, Svalbard)
PublicationThe expansion of glacier‐free areas in polar regions favours the appearance of lakes in the non‐glaciated parts of glacier basins. This paper presents the differentiation of organic compound concentrations in fifty‐four Arctic lakes collected in four locations (Logne Valley, in the vicinity of the Scott, Renard and Antonia glaciers). We cover meteorological measurements, chemical analysis of sixteen dioxin‐like compounds (Polycyclic...
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Analysis of chiral pharmaceutical residues in influent and effluent samples at racemic and enantiomeric level using liquid chromatography-tandem mass spectrometry
PublicationIn this work, two different chromatographic methods for seasonal monitoring of pharmaceutical residue in wastewater samples were developed. In the case of enantiomeric separation of selected compounds, LC-MS technique combining with vancomycin based chiral stationary phase was used. The performance of chiral analysis enabled to monitor the pharmaceutical contamination at the enantiomeric level. The d-SPE procedure was developed...
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Elementary analysis and energetic potential of the sludge from the Gdynia Dębogórze and Lębork wastewater treatment plants
PublicationThe paper aims to show the results of the elementary analysis of the sewage sludges from wastewater treatment plants in Gdynia Dębogórze and Lębork as well as measurements of the heat of combustion and the calculated calorific values according to regulation PN-93/Z-15008, taking into account water content and the composition of sewage sludge at different utilisation stages. The results presented in this paper are based on the analysis...
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Experimental Testing of Innovative Cold-Formed "GEB" Section / Badania Eksperymentalne Innowacyjnego Kształtownika Giętego Na Zimno Typu „Geb“
PublicationOne of the major advantages of light gauge steel structures made of cold-formed steel sections is their low weight, so manufacturers are increasingly using the possibilities of those sections for the production of typical single-storey steel structures systems. Well known profiles, such as Z, C and the so called hat sections that have been studied and described in the literature, are used mainly as purlins or truss components....
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On Symmetry of Uniform and Preferential Attachment Graphs
PublicationMotivated by the problem of graph structure compression under realistic source models, we study the symmetry behavior of preferential and uniform attachment graphs. These are two dynamic models of network growth in which new nodes attach to a constant number m of existing ones according to some attachment scheme. We prove symmetry results for m=1 and 2 , and we conjecture that for m≥3 , both models yield asymmetry with high...
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Novel Polyurethanes as Antifouling Paint Matrices
PublicationThe new poly(ester-ether urethane)s (PEEUR) were prepared in two stage synthesis from formerly obtained oligo(alkylene ester-ether)diols (OAEE) and 4,4‘-diphenylmethane diisocyanate (MDI). PEEUR samples were subjected to crosslinking with styrene in the presence of radical polymerization initiators: methyl ethyl ketone peroxide (MEKPO) or cobalt 2-ethyl cyclohexanoate (EtHCo). Crosslinked PEEUR were characterized by their physicochemical...
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Damage imaging algorithm for non-destructive inspection of CFRP/steel adhesive joints based on ultrasonic guided wave propagation
PublicationThe paper concerns assessing the quality of the adhesive connection between a steel plate and the reinforcing CFRP laminate. A three-stage algorithm for non-destructive damage imaging was developed. As the first step, an initial study involving dispersion curves of joint components was executed to determine the material parameters and the appropriate excitation frequency. During the second step, damage identification in three-layer...
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An Experimentally Aided Operational Virtual Prototyping to Obtain the Best Spindle Speed during Face Milling of Large-Size Structures
PublicationAbstract: The paper presents an original method concerning the problem of vibration reduction in the general case while milling large-size and geometrically complex details with the use of an innovative approach to the selection of spindle speed. A computational model is obtained by applying the so-called operational approach to identify the parameters of the workpiece modal model. Thanks to the experimental modal analysis results,...
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Scaling Up the Process of Titanium Dioxide Nanotube Synthesis and Its Effect on Photoelectrochemical Properties
PublicationIn this work, for the first time, the influence of scaling up the process of titanium dioxide nanotube (TiO2NT) synthesis on the photoelectrochemical properties of TiO2 nanotubes is presented. Titanium dioxide nanotubes were obtained on substrates of various sizes: 2 × 2, 4 × 4, 5 × 5, 6 × 6, and 8 × 8 cm2. The electrode material was characterized using scanning electron microscopy as well as Raman and UV–vis spectroscopy in order...
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The Role of Proteins in Food
PublicationThis chapter describes the effect of proteins on the sensory attributes and the biological value and safety of foods. The role of proteins depends on their amino acid composition and structure, on changes due to storage and processing, as well as on interactions with other food components. The effect on the sensory quality of foods is brought about by hydrophobicity, solubility, water holding capacity, gelling, film formation,...
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Implementation of DEIS for reliable fault monitoring and detection in PEMFC single cells and stacks
PublicationDynamic Electrochemical Impedance Spectroscopy (DEIS) was presented as novel method for diagnostic and monitoring of PEMFC stack and single cells operation. Impedance characteristics were obtained simultaneously with current - voltage characteristics for stack and each individual cell. Impedance measurements were performed in galvanodynamic mode. It allowed to compare performance of each cell and identification of faulty cell operation...
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COMPARISON OF BLOOD PRESSURE PREDICTION METHODS
PublicationIn the paper dierent approaches of predicting blood pressure values are presented. Basically, two methods and theirs modifications are considered. In total, seven algorithms have been examined. Tests have been conducted using both synthetic and clinical data. From our study it follows that none of the examined methods is superior to other.
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Błędy w przedstawianiu wyników pomiarów i wartości wielkości fizycznych popełniane w pracach studenckich
PublicationArtykuł powstał na bazie doświadczeń zdobytych podczas pracy dydaktycznej autora jako wykładowcy i nauczyciela akademickiego prowadzącego zajęcia w Laboratorium Podstaw Metrologii. Przytoczono przykłady nieprawidłowości w przedsta-wianiu wyników pomiarów i wartości wielkości fizycznych pochodzące z prac pisemnych studentów i skonfrontowano je z zaleceniami Międzynarodowego Układu Jednostek Miar (SI), oraz polskimi aktami prawnymi.
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Przydatność urządzenia zmechanizowanego do wyznaczania trwałości ściernic do przecinania ręcznego
PublicationW artykule przedstawiono porównawcze wyniki badań trwałości ściernic do przecinania ręcznego, zużywanych na dwóch urządzeniach: z całkowicie ręcznym prowadzeniem przez operatora narzędzia i na urządzeniu zautomatyzowanym symulującym warunki przecinania ręcznego ściernicą. Wykazano, że dla tych dwóch urządzeń nie ma istotnej statystycznie korelacji pomiędzy wartościami wskaźnika wydajności względnej GA, reprezentującego trwałość...
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Towards Robust Identification of Nonstationary Systems
PublicationThe article proposes a fast, two-stage method for the identification of nonstationary systems. The method uses iterative reweighting to robustify the identification process against the outliers in the measurement noise and against the numerical errors that may occur at the first stage of identification. We also propose an adaptive algorithm to optimize the values of the hyperparameters that are crucial for this new method.
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Social enterprises as a fertile ground for reducing social and economic exclusion - good practice examples from Poland
PublicationThe work briefly outlines the two dimensions of value generated by social enterprises to the economy and society. This is done in reference to the social cooperatives in Poland that are good examples of social enterprises according to EMES indicators
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Standardy Profesjonalnego Public Relations
Publication" Standardy przedstawiają wartości i pryncypia uzasadniające konieczność dokonywania odpowiednich wyborów. Public relations ma godzić interesy zleceniodawców, przedstawicieli mediów i różnych grup społeczeństwa, a przy tym pozostawać w zgodzie z normami etycznymi i odwoływać się do takich wartości jak szacunek, godność, rzetelność, uczciwość, prawda, wiarygodność, niezależność, lojalność i zaufanie. Opracowanie "Standardów profesjonalnego...
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Automated Valuation Model based on fuzzy and rough set theory for real estate market with insufficient source data
PublicationObjective monitoring of the real estate value is a requirement to maintain balance, increase security and minimize the risk of a crisis in the financial and economic sector of every country. The valuation of real estate is usually considered from two points of view, i.e. individual valuation and mass appraisal. It is commonly believed that Automated Valuation Models (AVM) should be devoted to mass appraisal, which requires a large...
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Ab initio and density functional theory calculations of proton affinities for volatile organic compounds
PublicationThe Hatree-Fock method with 6-311G** split-valence molecular orbitals basis sets and the density function theory-B3LYP have been applied to geometrical optimizations and calculations of total electronic, zero point vibrational energies and proton affinities at 298 K for volatile organic compounds. Calculated values of proton affinities are compared with experimental data.
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Monoubiquitinated Histone H1B Is Required for Antiviral Protection in CD4+T Cells Resistant to HIV-1
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Effect of bitumen characteristics obtained according to EN and Superpave specifications on asphalt mixture performance in low-temperature laboratory tests
PublicationThe paper aims to identify those characteristics of bitumen which have the greatest impact on asphalt mixture low-temperature performance. It was observed that stiffness and m-value of bitumen from BBR test were moderately related to stiffness and m-value of asphalt mixture obtained from 3 PB test. Simultaneously those rheological properties significantly impact on cryogenic stresses induced during TSRST test. The multiple regression...
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Utilization of ionic liquids for the enrichment of biogas
PublicationThis article discusses the dependence of biogas composition on organic feed material. High amounts of CO2 decrease the calorific value of biogas. Several technologies are reviewed which can be used to increase the calorific value. Special emphasis is laid on ionic liquids as a new absorbing material. ILs have a number of advantages due to their unique properties such as: low melting point, high thermal conductivity, no flammability,...
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A mechanistic model for fate and removal of estrogens in biological nutrient removal activated sludge systems
PublicationTwo estrogen fate and transformation models were integrated with a comprehensive activated sludge model (ASM) to predict estrogen removal based on biomass and solids production. Model predictions were evaluated against published full-scale plant data as well as results from a laboratory-scale sequencing batch reactor (SBR) fed synthetic wastewater. The estrogen fate model relating the rate of total estrogen degradation to soluble...
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Filozofować z głębi człowieczeństwa. O fenomenologii Andrzeja Półtawskiego.
PublicationDokonując krytyki tradycji nowożytnego empiryzmu i kartezjańskiego dualizmu Półtawski tworzy realistyczną i dynamiczną interpretację bytu ludzkiego. Przeżywanie, odczuwanie zmysłowe nie jest poślednią odmianą poznania jak i operacją dostarczania jedynie elementów, budulca poznaniu, ale odrębnym sposobem bycia w świecie, jest symbiotycznym kontaktem z otoczeniem, formą życia. Zrywa on radykalnie z tradycją brentanowsko-husserlowską...
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Quasi-solutions for generalized second order differential equations with deviating arguments
PublicationThis paper deal with boundary value problems for generalized second order differential equations with deviating arguments. Existence of quasi-solutions and solutions are proved by monotone iterative method. Examples with numerical results are added.
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Identification of defected sensors in an array of amperometric gas sensors
PublicationPurpose Amperometric gas sensors are commonly used in air quality monitoring in long-term measurements. Baseline shift of sensor responses and power failure may occur over time, which is an obstacle for reliable operation of the entire system. The purpose of this study is to check the possibility of using PCA method to detect defected samples, identify faulty sensor and correct the responses of the sensor identified as faulty. Design/methodology/approach In...
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Predicting cutting power for band sawing process of pine and beech wood dried with the use of four different methods
PublicationWood drying is an important stage in the woodworking process. After drying, wood is subject to a re-sawing process, for which a high quality surface, low material loss, and high efficiency are often required. In this paper, forecasted values were presented of cutting power for the re-sawing process of pine and beech wood that were dried with four different methods. Forecasting of cutting power for an industrial band saw machine...
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A technique of experiment aided virtual prototyping to obtain the best spindle speed during face milling of large-size structures
PublicationThe paper presents an original method concerning vibration suppression problem during milling of large-size and geometrically complicated workpieces with the use of novel way of selecting the spindle speed. This consists in repetitive simulations of the cutting process for subsequent values of the spindle speed, until the best vibration state of the workpiece is reached. An appropriate method of obtaining a computational model,...
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Machine Learning Algorithm-Based Tool and Digital Framework for Substituting Daylight Simulations In Early- Stage Architectural Design Evaluation
PublicationThe aim of this paper is to examine the new method of obtaining the simulation-based results using backpropagation of errors artificial neural networks. The primary motivation to conduct the research was to determine an alternative, more efficient and less timeconsuming method which would serve to achieve the results of daylight simulations. Three daylight metrics: Daylight Factor, Daylight Autonomy and Daylight Glare Probability have...
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The importance of the shape of the protein-water interface of a kinesin motor domain for dynamics of the surface atoms of the protein
PublicationSingle kinesin motor domain immersed in water has been investigated using molecular dynamics. It has been found that local properties of water in solvation shell change along with the nature of neighboring protein surface. However, a detailed analysis leads to the conclusion that the geometrical features of hydrogen bonds and overall structure of kinesin hydration water is not very different from bulk water. The local values of...
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Histogram of Oriented Gradients with Cell Average Brightness for Human Detection
PublicationA modification of the descriptor in a human detector using Histogram of Oriented Gradients (HOG) and Support Vector Machine (SVM) is presented. The proposed modification requires inserting the values of average cell brightness resulting in the increase of the descriptor length from 3780 to 3908 values, but it is easy to compute and instantly gives ≈ 25% improvement of the miss rate at 10‒4 False Positives Per Window (FPPW). The...
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Block Conjugate Gradient Method with Multilevel Preconditioning and GPU Acceleration for FEM Problems in Electromagnetics
PublicationIn this paper a GPU-accelerated block conjugate gradient solver with multilevel preconditioning is presented for solving large system of sparse equations with multiple right hand-sides (RHSs) which arise in the finite-element analysis of electromagnetic problems. We demonstrate that blocking reduces the time to solution significantly and allows for better utilization of the computing power of GPUs, especially when the system matrix...