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Research on Linear Actuators for Active Foil Bearings
PublicationActive foil bearings are a kind of gas foil bearing. They contain actuators which allow for modification of the bearing sleeve size and the shape of the lubrication gap. Rotor vibrations can be actively controlled by these changes. It is possible, among other things, to reduce the starting torque, control the vibration amplitude at different speeds and improve operational safety. Prototypes of active foil bearings are being developed...
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Prediction of Pile Shaft Capacity in Tension Based on Some Direct CPT Methods—Vistula Marshland Test Site
PublicationThis paper presents different CPT methodologies for the prediction of the pile shaft resistance in tension on the example of three reference screw piles of the Jazowa test site in Poland. The shaft capacity was estimated based on the cone resistance, sleeve friction and CPT excess pore water pressure. Three piles with diameter 0.4 m and the length varied from 8 m to 14.6 m were subjected to static load tests in tension. Their...
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Synthesis and characterisation of starch cuprate
PublicationThe cupration of granular potato starch with ammonium tetrachlorocuprate(II) was performed by a 20 min lasting microwave-assisted process and by 40 min convectional heating. In both cases the degree of esterification (DE) did not exceed 0.0064. A higher dose of cuprate had a positive effect on DE, regardless of whether the microwave irradiation or the convectional heating was applied, and on the thermal stability of the starch...
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The Possibility to use a Nuclear Power Plant as a Source of Electrical Energy and Heat
PublicationIn this article issues concernig the possibility of nuclear power plant (NPP) operation also as a source of heat, which means combined heat and power production, have been described. CHP work is possible and profitable only in those areas where high thermal power demand occurs, which means near city agglomerations such as Warsaw or the Tri-City. Two levels of thermal power delivered to the heating system have been considered. Preliminary...
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The dynamic performance analysis of the Micro-turbine's rotor supparted on slide and roling element bearings
PublicationThis article presents the results of investigations of dynamic characteristics of a small-dimension rotor with slide and rolling element bearings. The object of investigations was the rotor-bearing system designed for the ORC based low-power steam micro-turbine. The investigations were performed using MESWIR series programs, as well as commercial FEA software ABAQUS and MADYN 2000. The results of modal analysis of the micro-rotor...
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Kalanchoe sp. Extracts—Phytochemistry, Cytotoxic, and Antimicrobial Activities
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Interaction of Acoustic and Thermal Modes in the Vibrationally Relaxing Gases. Acoustic Cooling
PublicationThe dynamic equation which governs an excess temperature associated with the thermal mode in vibrationally relaxing gas is derived. The nonlinear transfer of acoustic energy to the energy of the thermal mode in a relaxing gas causes slow variation of temperature with time. The nal dynamic equation is instantaneous. All types of sound, including aperiodic, may be considered as an acoustic source of corresponding heating or cooling....
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Fractional Order Dynamic Positioning Controller
PublicationImproving the performance of Dynamic Positioning System in such applications as station keeping, position mooring and slow speed references tracking requires improving the position and heading control precision. These goals can be achieved through the improvement of the ship control system. Fractional-order calculus is a very useful tool which extends classical, integer-order calculus and is used in contemporary modeling and control...
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Tribological model of porous bearings with particular attention given to the lubricant lubricity
PublicationThe friction and wear problems, accompanying all the tribological systems, lead to reduced service life. In order to prevent such situation, it is necessary to maintain fluid friction, which improves durability of all friction nodes in a tribological system. In the paper, the tribological system consists of porous bearings and the model deals with their weakest spots - the oil outflow points in the porous wall. A kinetic model...
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On the Nonlinear Effects of Magnetoacoustic Perturbations in Optically Thin Quasi-Isentropic Plasmas
PublicationNonlinear effects of planar magnetosound perturbations in a plasma are discussed. Plasma is non-adiabatic due to optically thin radiation and external heating. For these reasons, thermal instability of a plasma may appear which makes it acoustically active. The plasma is assumed to be initially homogeneous ideal gas with infinite electrical conductivity permeated by a straight magnetic field which is orthogonal to the trajectories...
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Prediction of pile shaft capacity in tension based on some direct CPT methods – Vistula Marshland test site
PublicationThis paper presents different CPT methodologies for the prediction of the pile shaft resistance in tension on the example of three reference screw piles of the Jazowa test site in Poland. The shaft capacity was estimated based on the cone resistance, sleeve friction and CPT excess pore water pressure. Three piles with a diameter of 0.4 m and the length...
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Badania eksperymentalne słupów CFST z betonem zwykłym i ekspansywnym
PublicationPraca przedstawia badania eksperymentalne ponad 40 słupów CFST. Analizie poddano wyniki siły niszczącej słupy w aspekcie grubości stalowego płaszcza, smukłości słupa, rodzaju betonu wypełniającego stalową rurę (zwykły i ekspansywny) i jego wytrzymałości a także sposobu obciążania słupa (przez rdzeń lub przez cały przekrój). Sprawdzono efektywność słupów CFST z użyciem betonu ekspansywnego i zwykłego rozumianą jako stosunek nośności...
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Charakterystyka eksploatacyjna pomp ciepła zainstalowanych w oczyszczalni ścieków
PublicationW artykule przedstawiono charakterystykę eksploatacyjną sprężarkowych pomp ciepła zainstalowanych w oczyszczalni komunalnej i wykorzystujących ścieki oczyszczone jako dolne źródło ciepła. Zastosowanie ścieków oczyszczonych jest uzasadnione ich dostępnością oraz stosunkowo wysoką temperaturą (10-25°C). Prawidłowa eksploatacja układu wymaga zastosowania pośredniego obiegu parowacza oraz regularnych zabiegów czyszczenia wymiennika...
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Characterization of structural, thermal and mechanical properties of bismuth silicate glasses
Publicationhe influence of heating and reduction processes on the structural, thermal and mechanical properties of bismuth-silicate glasses has been investigated. Two compositions of glasses: 40Bi2O3–60SiO2 (Bi0.57Si0.43Ox) and 27Bi2O3–73SiO2 (Bi0.43Si0.57Ox) were fabricated by a typical melt quenching technique. Then the reduction in hydrogen at 380 °C for 20, 42 or 67 h was performed. It was found that a 50 μm-thick layer was formed on...
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Analysis of data fusion algorithms for the vessel with the dynamic positioning system
PublicationThe dynamic positioning (DP) system on the vessel is operated to control the position and heading of the vessel with the use of propellers and thrusters installed on the board. On DP vessels redundant measurement systems of position, heading and the magnitude and direction of environmental forces are required for safety at sea. In this case, a fusion of data is needed from individual measurement devices. The article proposes a...
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Activation of endogenous regenerative potential in mammals using epigenetic inhibitor zebularine
PublicationIn this work, a nucleoside inhibitor of DNA methyltransferases, zebularine, was investigated as a wound healing and regeneration promoting agent. It was found that a high dose of intraperitoneally delivered zebularine improved punch wound closure in the ear pinna in mice. Both cytidine, a zebularine analogue, and uridine, a zebularine metabolite, did not promote ear pinna hole closure. The effect of zebularine on ear pinna healing...
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Examination of epigenetic inhibitor zebularine in treatment of skin wounds in healthy and diabetic mice
PublicationDNA methyltransferase inhibitor zebularine was proven to induce regeneration in the ear pinna in mice. We utilized a dorsal skin wound model to further evaluate this epigenetic inhibitor in wound healing. Full-thickness excisional wounds were made on the dorsum of 2 and 10-month-old healthy BALB/c and 3 and 8-month-old diabetic (db/db) mice, followed by topical or intraperitoneal zebularine delivery. Depending on the strain, age,...
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Anthropogenic trace metals in Setiu Wetland: Spatial and seasonal distribution and implications for environmental health
PublicationThe growing urban wastewater volume poses a major global environmental challenge, especially in developing nations where inadequate treatment and discharge impact clean water availability. This study focused on Setiu Wetland, aiming to analyze seasonal and spatial variations of trace metals in particulate form from anthropogenic and pathogenic sources. Surface water samples were collected from multiple stations, measuring physical...
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Total domination in versus paired-domination in regular graphs
PublicationA subset S of vertices of a graph G is a dominating set of G if every vertex not in S has a neighbor in S, while S is a total dominating set of G if every vertex has a neighbor in S. If S is a dominating set with the additional property that the subgraph induced by S contains a perfect matching, then S is a paired-dominating set. The domination number, denoted γ(G), is the minimum cardinality of a dominating set of G, while the...
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Total Domination Versus Domination in Cubic Graphs
PublicationA dominating set in a graph G is a set S of vertices of G such that every vertex not in S has a neighbor in S. Further, if every vertex of G has a neighbor in S, then S is a total dominating set of G. The domination number,γ(G), and total domination number, γ_t(G), are the minimum cardinalities of a dominating set and total dominating set, respectively, in G. The upper domination number, \Gamma(G), and the upper total domination...
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Chromogenic azomacrocycles with imidazole residue: Structure vs. properties
PublicationNew diazo macrocycles linked by hydrocarbon chain bearing imidazole or 4-methylimidazole residue have been synthetized with satisfactory yield (24–55%). The structure of macrocycles was confirmed by X-ray analysis and spectroscopic methods (1H NMR, MS, FTIR). Metal cation complexation studies were carried out in acetonitrile and acetonitrile-water system. It was found that azomacrocyles form triple-decker complexes with lead(II)....
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Current based Normalized Triple Covariance as a bearings diagnostic feature in induction motor
PublicationDiagnosis of induction motors, conducted remotely by measuring and analyzing the supply current is attractive with the lack of access to the engine. So far there is no solution, based on analysis of current, the credibility of which allow use in industry. Statistics of IM bearing failures of induction motors indicate, that they constitute more than 40% of IM damage, therefore bearing diagnosis is so important. The article provides...
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Induction Motor Bearings Diagnostic Using MCSA and Normalized Tripple Covariance
PublicationDiagnosis of induction motors, conducted remotely by measuring and analyzing the supply current is attractive with the lack of access to the engine. So far there is no solution, based on analysis of current, the credibility of which allow use in industry. Statistics of IM bearing failures of induction motors indicate, that they constitute more than 40% of IM damage, therefore bearing diagnosis is so important. The article provides...
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RESEARCH ON HYDRODYNAMIC PEEK JOURNAL BEARINGS LUBRICATED WITH WATER AND OIL
PublicationThe main purpose of the research was to determine the possibilities and experimentally test the benefits of replacing conventional oil lubrication with ecological water lubrication. Tests were carried out on a test rig for hydrodynamic radial bearings under conditions representative of the expected applications for the bearing in water turbines. Bearings made from the polymer material PEEK (polyether ether ketone) were tested under static...
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Scene Segmentation Basing on Color and Depth Images for Kinect Sensor
PublicationIn this paper we propose a method for segmenting single images from Kinect sensor by considering both color and depth information. The algorithm is based on a series of edge detection procedures designed for particular features of the scene objects. RGB and HSV color planes are separately analyzed in the first step with Canny edge detector, resulting in overall color edges mask. In depth images both clear boundaries and smooth...
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Zmiany składu chemicznego wód podziemnych na obszarze Żuław Wielkich w ujęciu historycznym i współcześnie
PublicationBadania hydrogeologiczne Żuław Wielkich koncentrują się na zasoleniu wód podziemnych. Od początku XX wieku do chwili obecnej obserwuje się wysokie stężenia chlorków, jonów amonowych i mineralizacji we wszystkich poziomach wodonośnych. Uznaje się, iż na przeważającym obszarze nie występują tu warstwy wodonośne o znaczeniu użytkowym, a zasoby wód podziemnych Żuław Wielkich są ograniczone. Przeprowadzone...
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Sympathetic neural responses to smoking are age dependent
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Heightened acute circulatory responses to smoking in women
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MOŻLIWOŚĆ WYKORZYSTANIA ELEKTROWNI JĄDROWEJ JAKO ŹRÓDŁA ENERGII ELEKTRYCZNEJ I CIEPLNEJ
PublicationW niniejszym artykule przedstawiono zagadnienia związane z możliwością pracy elektrowni jądrowej (EJ) również w charakterze źródła ciepła, a więc w warunkach skojarzonego wytwarzania energii elektrycznej oraz ciepła. Rozpatrzono dwa poziomy mocy cieplnych oddawanych do systemów ciepłowniczych. Przeprowadzone wstępnie badania techniczne i ekonomiczne dla lokalizacji elektrowni jądrowej nad Jeziorem Żarnowieckim potwierdziły potencjalną...
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Assessment, optimisation and working fluid comparison of organic rankine cycle combined with negative CO2 gas power plant system
PublicationThis study aims to investigate the application of the Organic Rankine Cycle (ORC) as an alternative to low-pressure expansion in the negative CO2 power plant (nCO2PP). The reason for this study is that a detailed analysis of nCO2PP indicates a certain amount of waste heat present in the exhaust gas from the high-to-intermediate pressure gas turbine. Some of this energy can be used by the application of the expansion in a low-pressure...
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Technical and economic conditions of supplying residential consumers with heat from nuclear power plant
PublicationThe reduction of CO2 emission requires technological shift towards carbon-free options. Cogeneration of electricity and heat based on coal and natural gas will experience generation cost increase, if the costs of emissions are imposed on the plant operators. Therefore, nuclear and renewable options should be considered. In this paper, we present the concept of electricity and heat supply system with nuclear condensing turbine adapted...
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Water-Lubricated Sintered Bronze Journal Bearings—Theoretical and Experimental Research
PublicationWater lubricated bearings are used from many years in shipbuilding, hydro power and other industries because of their advantages such as: extensive serviceable life, low coefficient of friction, longevity of shaft sleeve, good abrasion resistance, low maintenance required, unit simplicity, no danger of pollution and low price. Various types of water lubricated sliding bearings have been tested at the Technical University of Gdansk...
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Pyrolysis of Pruning Residues from Various Types of Orchards and Pretreatment for Energetic Use of Biochar
PublicationThe routine pruning and cutting of fruit trees provides a considerable amount of biowaste each year. This lignocellulosic biomass, mainly in the form of branches, trunks, rootstocks, and leaves, is a potential high-quality fuel, yet often is treated as waste. The results of a feasibility study on biochar production by pyrolysis of residues from orchard pruning were presented. Three types of biomass waste were selected as raw materials...
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Attitudes of oncology patients’ towards biospecimen donation for biobank research
PublicationBackground Since the biological material that remains after diagnostic and therapeutic procedures plays crucial role in biobank research, this study aims to explore cancer patients’ views on the donation of biospecimens for research purposes. Methods 548 oncology patients from two hospitals with oncology treatment units in Poznan, Poland,...
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Transcriptomic responses to wounding: meta-analysis of gene expression microarray data
PublicationBackground A vast amount of microarray data on transcriptomic response to injury has been collected so far. We designed the analysis in order to identify the genes displaying significant changes in expression after wounding in different organisms and tissues. This meta-analysis is the first study to compare gene expression profiles in response to wounding in as different tissues as heart, liver, skin, bones, and spinal cord, and...
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Auditory-visual attention stimulator
PublicationNew approach to lateralization irregularities formation was proposed. The emphasis is put on the relationship between visual and auditory attention stimulation. In this approach hearing is stimulated using time scale modified speech and sight is stimulated by rendering the text of the currently heard speech. Moreover, displayed text is modified using several techniques i.e. zooming, highlighting etc. In the experimental part of...
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Mercury in the Polish part of the Baltic Sea: A response to decreased atmospheric deposition and changing environment
PublicationOur review of the literature showed that since the beginning of the socio-economic transformation in Poland in the 1990s, the downward trend in Hg emissions and its deposition in the southern Baltic Sea was followed by a simultaneous decrease in Hg levels in water and marine plants and animals. Hg concentrations in the biota lowered to values that pose no or low risk to wildlife and seafood consumers. However, in the first decade...
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Production of certified reference materials - homogeneity and stability study based on the determination of total mercury and methylmercury
PublicationReference materials (RMs) play an important role in all elements of the quality assurance system of measurements. In this work, ``package'' 4 new CRMs (bottom sediment, herring tissue, cod tissue, cormorant tissue) were prepared and characterised to carry out the quality control in monitoring analysis of mercury and methylmercury in environmental samples. Materials - candidates were collected in Poland and south part of the Czech...
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DIAGNOSTYKA ŁOŻYSK SILNIKA INDUKCYJNEGO PRZY UŻYCIU POMIARU PRĄDU ZASILAJĄCEGO I WIBRACJI
PublicationW artykule przedstawione zostały wyniki badań diagnostycznych łożysk silnika indukcyjnego z zastosowaniem metody pomiaru prądu zasilającego oraz wibracji. Poruszone zostały problemy dotyczące poszukiwania nowej metody opartej na pomiarze i analizie prądu, która w znacznym stopniu ułatwiłaby szybkie i sprawne znalezienie uszkodzenia w maszynie, bez konieczności bezpośredniego dostępu do badanego urządzenia. Zaprezentowano rezultaty...
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Analysis of The Behavior of Foundations of Historical Buildings
PublicationThe article is devoted to the analysis of the behavior of the foundations of historic buildings. Some basic aspects of foundation engineering are discussed, with an emphasis placed on its development, applied techniques, and materials. Several different approaches and methods for the analysis of foundations of historical buildings are presented. A particular analysis has been focused on an example of a typical stone foundation...
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POSSIBILITY OF IDENTIFICATION OF TECHNICAL CONDITION OF BEARINGS FOR SELF-IGNITION ENGINES BY APPLICATION OF ACOUSTIC EMISSION AS A DIAGNOSTIC SIGNAL
PublicationThis paper presents the results of empirical studies where the acoustic emission (AE) method was applied to identify the technical condition of sliding surfaces of main and crank bearings for main diesel engines. The test results indicate that the measurements of the AE parameters allow the technical condition identification for bearings of this type. The results refer to the measurements of the parameters for AE generated in the...
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Microwave heat treatment application to pasteurization of human milk
PublicationA prototype of microwave pasteurizer has been proposed as an alternative for holder pasteurization (HP) routinely used in Human Milk Bank (HMB), ensuring microbiological safety of human milk (HM). It was shown that the time of heat generation was about 15–16 min shorter by applying the microwave than in HP. Total inactivation of heat-sensitive bacteria Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus...
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Comparative study of operation of condensing and traditional boilers equipped with the ORC module for electricity generation
PublicationCondensing technology applied to boilers is to make full use of thermal energy contained in the fuel. That means that additionaly the heat from condensation of exhaust gases can be used for the purposes of heating the domestic hot water and to cover the demand for central heating. The study analyzed the operation of the "traditional" boiler equipped with the ORC module as the similar arrangement but with the condensing boiler....
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The Impact of Sloshing Liquids on Ship Stability for Various Dimensions of Partly Filled Tanks
PublicationLiquid sloshing phenomenon taking place in partly filled ships' tanks directly affects the stability of a vessel. However, only static calculations are carried out onboard ships nowadays and static transfer of liquid weight is taken into account in the course of routine stability calculation. The paper is focused on a dynamic heeling moment due to liquid sloshing in tanks onboard ships. A number of numerical simulations of liquid...
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A Method of Assessment of the Liquid Sloshing Impact on Ship Transverse Stability
PublicationLiquid sloshing phenomenon taking place in partly filled ships? tanks directly affects the stability of a vessel. However, only static calculations are carried out onboard ships nowadays and static transfer of liquid weight is taken into account in the course of routine stability calculation. The paper is focused on a dynamic heeling moment due to liquid sloshing in tanks onboard ships. The set of numerical simulations of liquid...
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The unstable thermoelectric effect in non-stoichiometric Cu2Se during the non-equilibrium phase transition
PublicationThe superionic α ↔ β phase transition in Cu1.96Se thermoelectric material is investigated by means of thermal analysis (DSC) and measurements of Seebeck coefficient and electrical conductivity. Results of the DSC measurements with 1–10 K/min heating and cooling rates show that the material is close to the equilibrium phase composition during the transformation. However, the kinetic limitation of the process exists, which is indicated...
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The Influence of Thin Gold Electrodes on the High-Temperature Impedance of Oxide Glasses
PublicationThe influence of thin gold electrodes on the electrical measurements of glasses at high temperatures was studied using impedance spectroscopy. The impedance was measured several times over a wide frequency range from 10 mHz to 1 MHz and the temperature ranged from 213 to 673 K under air and nitrogen atmospheres. The results showed a drop in the conductivity of more than an order of magnitude at a temperature around 603 K during...
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Distributed Detection of Selected Features in Data Streams Using Grid-class Systems
PublicationThis chapter describes basic methodology of distributed digital signal processing. A choice of distributed methods of detection of selected features in data streams using grid-class systems is discussed. Problems related to distribution of data for processing are addressed. A mitigating method for data distribution and result merging is described.
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Multi agent grid systems
PublicationThis chapter presents an idea of merging grid and volunteer systemswith multi agent systems. It gives some basics concerning multi agentsystem and the most followed standard. Some deliberations concerningsuch an existing systems were made in order to finally present possibilities of introducing agents into the Comcute system.
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Magnetic anisotropy and structural flexibility in the f ield-induced single ion magnets [Co{(OPPh2) (EPPh2)N}2], E = S, Se, explored by experimental and computational methods
PublicationDuring the last few years, a large number of mononuclear Co(II) complexes of various coordination geometries have been explored as potential single ion magnets (SIMs). In the work presented herein, the Co(II) S = 3/2 tetrahedral [Co{(OPPh2)(EPPh2)N}2], E = S, Se, complexes (abbreviated as CoO2E2), bearing chalcogenated mixed donor-atom imidodiphosphinato ligands, were studied by both experimental and computational techniques. Specifically,...