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Search results for: MULTIPARTITE CORRELATIONS
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Experimental Investigation of Free Convection Heat Transfer from Horizontal Cylinder to Nanofluids
PublicationThe results of free convection heat transfer investigation from a horizontal, uniformly heated tube immersed in a nanofluid are presented. Experiments were performed with five base fluids, i.e., ethylene glycol (EG), distilled water (W) and the mixtures of EG and water with the ratios of 60/40, 50/50, 40/60 by volume, so the Rayleigh (Ra) number range was 3 104 Ra 1.3 106 and the Prandtl (Pr) number varied from 4.4 to 176....
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Virulence of Clinical Candida Isolates
PublicationThe factors enablingCandidaspp. infections are secretion of hydrolytic enzymes, adher-ence to surfaces, biofilm formation or morphological transition, and fitness attributes. The aim of thisstudy was to investigate the correlation between known extracellular virulence factors and survivalofGalleria mellonellalarvae infected with clinicalCandida. The 25 isolates were tested and the activityof proteinases among 24/24, phospholipases...
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Burnout Investigation of Small Diameter Tubes Immersed in Nanofluids
PublicationThis paper deals with research into pool boiling critical heat flux (CHF) of water–Al2O3, water–TiO2 and water–Cu nanofluids on horizontal stainless steel tubes. The experiments were conducted under atmospheric pressure. Nanoparticles were tested at concentrations of 0.001%, 0.01%, 0.1% and 1% by weight. Ultrasonic vibration was used in order to stabilize the dispersion of the nanoparticles. Although dispersants were not used to...
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Territorial Aspects of Entrepreneurial Activity in Polish Suburban Zones
PublicationGlobalization has led to an increased correlation and integration of various fields in modern civilization, including those connected with allocation of entrepreneurial functions. Connection, on a global scale, has shown an increased significance of worldwide corporations. Territorial allocation of the entrepreneurial function has become the subject of translocation and revaluation. Translocation can be understood as the change...
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Laboratory investigation with subbottom parametric echosounder SES-2000 standard with an emphasis on reflected pure signals analysis
PublicationThe main goal of the paper is to describe correlations between measurements results of trials taken on Gulf of Gdańsk bottom sounded with parametric echosounder SES-2000 Standard and laboratory research where collected during survey sediments were measured. Stationary tests took place at Gdansk University of Technology where 30 meters long 1.8 meter deep and 3 meters wide water tank is located. Main lobe of antenna was directed...
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Polychlorinated biphenyls (PCBs) in bottom sediments: Identification of sources
PublicationPolychlorinated biphenyls (PCBs) can enter the environment from various sources. They are synthetic chemicals and as such are present in the environment mainly as mixtures containing various amounts of PCB congeners. It is therefore difficult to pinpoint the source of PCB emissions into the environment and the pathways along which they migrate there. The situation is different where locating the emission sources of polycyclic aromatic...
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BACTERIAL INACTIVATION VIA LASER-DRIVEN GOLD NANOPARTICLE HEATING: SIMULATION AND ANALYSIS
PublicationThis study utilizes CFD technique to simulate the inactivation of E. coli bacteria within a microfluidic chamber, employing gold nanoparticles irradiated by a laser beam. Employing a single-phase model, the presence of bacteria is considered by treating thermal properties in the governing equations as effective, combining those of water and bacteria using established correlations from scientific literature. The conversion of light...
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A closer look at how the dispersive liquid–liquid microextraction method works. Investigation of the effect of solvent mixture composition on the quality and stability of the cloudy state
PublicationThe dispersive liquid–liquid microextraction (DLLME) is one of the most popular miniaturized extraction procedures. In this paper, the degree of dispersion and dispersion stability were studied with the aim to assess the correlations of these parameters with efficiency for the selected analytical application. The dependence between the degree of dispersion (cloudy state quality) and its stability obtained by various emulsification...
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Flow boiling of R1233zd(E) in a 3 mm vertical tube at moderate and high reduced pressures
PublicationThe results of flow boiling of R1233zd(E) in a 3 mm vertical stainless steel tube are presented at moderate and high saturation temperatures. Integral flow characteristics in the form of pressure drop and heat transfer coefficient are discussed for saturation temperatures ranging from 115 to 145 °C (corresponding reduced pressures from 0.2 to 0.7), mass velocity of 800 kg/m2s and heat flux of 20 kW/m2. All of the obtained heat...
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Serum bisphenol A concentrations correlate with serum testosterone levels in women with polycystic ovary syndrome
PublicationThe aim of this study was to determine serum bisphenol A (BPA) concentrations using high performance liquid chromatography with tandem mass spectrometry (HPLC–MS/MS) in women with polycystic ovary syndrome (PCOS) (n=106, age range 18–40 yrs) and to evaluate its potential impact on their hormonal and metabolic profile. The control group consisted of age- and BMI-matched 80 eumenorrheic women with no clinical or biochemical hyperandrogenism....
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A semi-empirical model for flow boiling heat transfer with account of the reduced pressure effect
PublicationIn the present study the attention was focused on the influence of reduced pressure on the predictions of heat transfer during flow boiling at the extensive range of pressures. The results of calculations were to test the sensitivity of the in-house flow boiling model with respect to the selection of the appropriate two-phase flow multiplier, which is one of the distinctive elements of that model. For this purpose a few two-phase...
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Thermal-Hydraulic Studies on the Shell-and-Tube Heat Exchanger with Minijets
PublicationIn this paper a patented design of a heat exchanger with minijets, with a cylindrical construction is presented. It is followed by the results of its systematic experimental investigations in the single-phase convection heat transfer mode. Based on these results, validation of selected correlations (coming from the literature) describing the Nusselt number was carried out. An assessment of the heat exchange intensification level...
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Equivalent Single Layer Models in Free Vibration Analysis of Laminated Multi-Layered Plates
PublicationThe performance of selected equivalent single-layer (ESL) models is evaluated within several classical benchmark tests for small amplitude free vibration analysis of multi-layered plates. The authors elaborated their own Finite Element software based on the first-order shear deformation (FOSD) theory with some modifications incorporated including a correction of the transverse shear stiffness and an application of zigzag type functions....
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Experimental validation of the rolling resistance measurement method including updated draft standard
PublicationThe main objective of ROSANNE is the harmonisation and standardisation of the measurement of skid resistance, noise emission and rolling resistance of road pavements. Regarding rolling resistance characterisation, a draft for standardization of a harmonized procedure for classification of road surfaces across Europe has been prepared within WP3 (deliverable 3.5). The procedure deals with the direct measurement on real roads of...
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Insulin-like growth factor type 2 is better than insulin-like growth factor type 1 a survival marker in patients after acute decompensation of heart failure
PublicationIntroduction:A decreased IGF-1 has been found in heart failure (HF). There are no reports assessing IGF-2 in HF, although in vitro study has shown, that IGF-2 stimulates cardiomyocyte proliferation more than IGF-1. The study aim was to compare the IGF-1 and IGF-2 concentration depending on HF exacerbation and annual survival.Material and methods:Among 75 patients hospitalized...
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Nontoxic Goiter (NTG) and Radioiodine: What Do Patients Think About It? Quality of Life in Patients with NTG Before and After 131-I Therapy
PublicationObjective Despite numerous publications regarding nontoxic goiter (NTG) treatment and an increasing interest in patients’ quality of life, few studies present the outcome of 131-I treatment from the patients’ perspective. Our study’s main aim was to verify whether there is any improvement in life quality following 131-I treatment. Materials and methods Thirty-five patients with NTG qualified to participate in the study. All patients...
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Doskonalenie logistycznego łańcucha dostaw w usługach w ujęciu relacyjnym
PublicationW literaturze zagadnienia związane z modelami doskonałości zarządzania łańcuchem dostaw, modelami zarządzania relacjami, modelami doskonałości EFQM oraz obszarami logistycznymi funkcjonują rozłącznie. Opracowany model w postaci MAPY RELACJI pozwala na pokazanie jak wyglądają korelacje między obszarami logistycznymi, obszarami działalności w odniesieniu do modeli doskonałości EFQM, modelami doskonałości zarządzania łańcuchem dostaw...
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Analysis of an Attenuator Artifact in an Experimental Attack by Gunn–Allison–Abbott Against the Kirchhoff-Law–Johnson-Noise (KLJN) Secure Key Exchange System
PublicationA recent paper by Gunn–Allison–Abbott (GAA) [L. J. Gunn et al., Scientific Reports 4 (2014) 6461] argued that the Kirchhoff-law–Johnson-noise (KLJN) secure key exchange system could experience a severe information leak. Here we refute their results and demonstrate that GAA’s arguments ensue from a serious design flaw in their system. Specifically, an attenuator broke the single Kirchhoff-loop into two coupled loops, which is an...
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Evaluation of reformer tubes degradation after long term operation
PublicationPurpose of this paper is to show the effect of long-term service at elevated temperatures on microstructural changes of cast steel reformer tubes made of the alloy IN-519 (24%Cr, 24%Ni, Nb). The relationship between mechanical properties and microstructure degradation is discussed. Investigations were performed on five tubes taken from ammonia reformer furnace. Tubes worked at temperature of 880C and 3,2 MPa pressure. The operation...
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Application of electrochemical impedance spectroscopy to monitoring discharging process of nickel/metal hydride battery.
PublicationThis paper presents the possibility of applying impedance analysis to cell diagnostics. In order to obtain characteristic curves of both electrodes of a NiMH battery simultaneously, a reference electrode was added into the circuit. The authors analysed the cell under three cases, i.e. when its properties are determined only by the state of the positive electrode, only by the state of the negative electrode, or when both electrodes...
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Isothiocyanates may chemically detoxify mutagenic amines formed in heat processed meat
PublicationMeat consumption represents a dietary risk factor increasing the incidence of common cancers, probably due to carcinogenic amines (HAAs) formed upon meat heating. Interestingly, cancers whose incidence is increased by meat consumption, are decreased in populations consuming brassica vegetables regularly. This inverse correlation is attributed to brassica anticarcinogenic components, especially isothiocyanates (ITCs) that stimulate...
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Theoretical study of the photoelectron spectrum of ethyl formate: Ab initio and density functional theory investigation
PublicationThe first ionization energy and associated photoelectron spectrum of ethyl formate are investigated with quantum chemistry calculations. The geometries, harmonic vibrational frequencies and first ionization energy are computed at the Hartree-Fock (HF) and at the second order Moller-Plesset perturbation theory (MP2). Moreover, accurate ionization energies are obtained with the Coupled-Cluster theory including singles and doubles...
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Sandwich Biobattery with Enzymatic Cathode and Zinc Anode Integrated with Sensor
PublicationCarbon paper covered with side-naphthylated multi walled carbon nanotubes was used as the conducting support for the construction of a biocathode in a hybrid biofuel cell. Laccase Carrena unicolor enzyme was employed as the catalyst for the 4e reduction of oxygen and a zinc disc covered with hopeite was used as the anode. Derivatized carbon nanotubes increase the working surface of the electrode and provide direct contact with...
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Development of different methods for drugs and psychoactive substances extraction from hair samples and their identification based on HPLC-ESI-QTOF analysis
PublicationOver the past decade, the use of non-controlled designer drugs and drug of abuse has rapidly increased. Hair, as a human matrix, enables detection of drugs incorporated into its structure. Studies of presence and identification of drug metabolites in human hair samples has been performed using liquid chromatography electrospray ionization quadrupole time of flight mass spectrometry (HPLC-ESI-QTOF-MS) with steady alternation of...
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Temperature-dependent structure-property modeling of viscosity for ionic liquids
PublicationIn this paper we present the methodology for assessing the ionic liquids' viscosity at six temperature points (25, 35, 45, 50, 60 and 70 [C]), which utilizes only the in silico approach. The main idea of such assessment is based on the "correction equation" describing the correlation between experimentally measured viscosity and theoretically derived density (calculated with use of molecular mechanics), given at 6 different temperature...
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Isolation of Citrus lemon extracellular vesicles: Development and process control using capillary electrophoresis
PublicationA new and scalable method for the isolation of extracellular vesicles (EV) from Citrus lemon juice samples was developed. The methodology included preliminary preconcentration of the sample using ultrafiltration (UF) followed by size-exclusion chromatography (SEC) purification and final preconcentration of the eluates. Transmission electron microscopy and proteomic analysis showed that isolates contained exosome-like vesicles, exocyst-positive...
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Dispersive Micro‐Solid Phase Extraction of Selected Metals in Water and Food Samples Followed by ICP‐OES Analysis: Method Development, Analysis of Real Samples and Greenness Evaluation
PublicationMultiwalled carbon nanotubes (MWCNTs) are well-known adsorbents because of their high surface area, layered and hollow architecture, hydrophobicity, and multiple and easily accessible adsorption sites. In this study, MWCNTs were used for dispersive micro-solid-phase extraction of various metal chelates in environmental and food samples. Different parameters such as concentration of the chelating reagent, the sorbent dosage, the...
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Numerical Modelling of Forced Convection of Nanofluids in Smooth, Round Tubes: A Review
PublicationA comprehensive review of published works dealing with numerical modelling of forced convection heat transfer and hydrodynamics of nanofluids is presented. Due to the extensive literature, the review is limited to straight, smooth, circular tubes, as this is the basic geometry in shell-and-tube exchangers. Works on numerical modelling of forced convection in tubes are presented chronologically in the first part of the article....
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The Influence of Low-Temperature Disintegration on the Co-Fermentation Process of Distillation Residue and Waste-Activated Sludge
Publication: Innovative low-temperature disintegration (process temperature 55 ◦C and oxygen concentration 0.2 mg/dm3 ) can be an economically rational technology to intensifying energy production from renewable sources. The proposed process can achieve a degree of disintegration—under optimal conditions—of about 50%, which is excellent when compared with other methods of feed pre-treatment. The low-temperature disintegration of distillation...
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Rapid Evaluation of Poultry Meat Shelf Life Using PTR-MS
PublicationThe use of proton transfer reaction mass spectrometry (PTR-MS) for freshness classification of chicken and turkey meat samples was investigated. A number of volatile organic compounds (VOCs) were selected based on the correlation (> 95%) of their concentration during storage at 4 °C over a period of 5 days with the results of the microbial analysis. In order to verify if the selected compounds are not sample-specific, a number...
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Origin of bitumen fractions in the Jurassic-early Cretaceous Vaca Muerta Formation in Argentina: insights from organic petrography and geochemical techniques
PublicationThis paper investigates chemical functional groups of the two extracted bitumen fractions in shales of the Jurassic to early Cretaceous Vaca Muerta Formation of the Neuquén Basin in Argentina, South America. The results indicate that Bitumen I is strongly aliphatic and appears to be genetically related to fluorescent amorphous organic matter. In contrast, Bitumen II consists of highly condensed, aromatic hydrocarbons, and has some...
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A novel calibration method for RSS-based DoA estimation using ESPAR antennas
PublicationIn this paper, we introduce a new calibration method that can successfully be used in direction of arrival (DoA) estimation using electronically steerable parasitic array radiator (ESPAR) antennas and employing power-pattern cross-correlation (PPCC) algorithm, which relies on received signal strength (RSS) values recorded at the antenna output port. Instead of the commonly used two-step approach, during which ESPAR antenna calibration...
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A CONCEPT OF DETERMINING THE RELATION BETWEEN LOAD AND WEAR OF TRIBOLOGICAL SYSTEMS OF SHIP MAIN SELF-IGNITION ENGINES BY USING PROBABILISTIC APPROACH PROBABILISTIC APPROACH
PublicationThis paper presents a proposal of simultaneous consideration of load and wear associated with it , of tribological systems of ship main engines (intended for ship propulsion) . Based on results of investigations it was assumed that both the load Q (i.e. a cause of wear ) and the wear Z (i.e. an effect of load occurrence) considered in a given time t(0 ≤ t ≤ t) are random variables Qt and Zt, respectively. There was characterized...
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Threshold Attendance under Soft-Crash Model: TAG Protocol and Markovian Analysis
PublicationA realistic and systematic network evaluation should subsume an availability model and a failure model. We combine a "hard availability" model we call threshold attendance, whereby a certain minimum number of network elements must be present at any time, with a soft-crash failure model, whereby after experiencing a failure, a network element is still able to function correctly for a while in an emergency mode at a risk of a major...
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Threat intelligence platform for the energy sector
PublicationIn recent years, critical infrastructures and power systems in particular have been subjected to sophisticated cyberthreats, including targeted attacks and advanced persistent threats. A promising response to this challenging situation is building up enhanced threat intelligence that interlinks information sharing and fine-grained situation awareness. In this paper a framework which integrates all levels of threat intelligence...
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Transdermal transport of collagen and hyaluronic acid using water in oil microemulsion
PublicationCollagen and hyaluronic acid (HA) are biopolymers that affect the appearance and condition of the skin. Delivery of these compounds into the skin is highly challenging since have a number of disadvantageous properties, such as high molecular weight and hydrophilicity. Here, we evaluated the transdermal penetration of low and high molecular weight collagen and HA from microemulsions. A number of microemulsion formulations, differing...
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Within- and between-person factor structure of the Oldenburg Burnout Inventory: Analysis of a diary study using multilevel confirmatory factor analysis
PublicationThe study examined the factor structure of burnout, as measured with the Oldenburg Burnout Inventory. The participants were 235 employees of a public administration agency who assessed their burnout online for 10 consecutive working days. Two models were tested with multilevel confirmatory factor analysis, assuming the same one or two-factor structure at the within- and between-person levels. Both models showed a reasonable fit...
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Study of probe signal bandwidth influence on estimation of coherence bandwidth for underwater acoustic communication channel
PublicationA signal transmitted in a shallow Underwater Acoustic Communication (UAC) channel suffers from time dispersion due to the multipath propagation and the refraction phenomena. This causes intersymbol interference of the received signal and frequency-selective fading observed in its spectrum. Coherence bandwidth is one of the key transmission parameters used for designing the physical layer of a data transmission system to minimise...
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IDEA SMART CITY W KONTEKŚCIE ROZWOJU PRZEDSIĘBIORCZOŚCI NA PRZEDMIEŚCIACH
PublicationSmart City Concept in the Context of Enterpreneurship Development in Suburban Areas. Supporting innovation and knowledge within economic development, these are the goals of public managers, enthusiasts of the Smart City concept. It is questioned whether this concept is the best solution for regional development and efficient support to local entrepreneurship based on SMEs (small and medium enterprises). Moreover, the results of...
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Study on applicability of two modal identification techniques in irrelevant cases
PublicationStudy on applicability of two modal identification techniques in irrelevant cases is made in this paper. The following techniques are considered: Peak Picking based on correlation analysis (PP-CA), dedicated for ambient vibrations and Eigensystem Realization Algorithm (ERA), formulated for free decay vibrations investigation. Irrelevant cases are found when analyzed signals are different than recommended to a given technique. The...
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Timed rolling and rising tests in Duchenne muscular dystrophy ambulant boys: a feasibility study
PublicationBACKGROUND: Functional activities are extensively used in motor assessments of patients with Duchenne muscular dystrophy. The role of timed items has been reported as an early prognostic factor for disease progression. However, there are two functional activities that are not widely assessed in clinical practice among Duchenne muscular dystrophy patients: rolling and bed rising. This study aimed to investigate whether the 360-degree...
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Experimental and comparative study on the two-phase pressure drop of air-water mixture in U-bend and straight pipe annuli
PublicationIn this paper, the experimental and theoretical analysis of pressure drop in singlephase and two phase-flow were presented for straight and U-bend smooth tube annulus and tube annulus with wire coil insert. Experiments for various boundary conditions were performed. In case of U-tube and straight tube with and without turbulator, tests were made for the water-water and air-water systems. The study covered a wide measuring range,...
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Equivalent single-layer models in deformation analysis of laminated multilayered plates
PublicationThe performance of selected Equivalent Single-Layer (ESL) models is evaluated within several classical benchmark tests for linear static analysis of multi-layered plates. The authors elaborated their own Finite Element software based on the first-order shear deformation theory (FOSD) with some modifications incorporated including a correction of the transverse shear stiffness and an application of zig-zag type functions. Seven...
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Inwestycje w surowce w połączeniu z polskim rynkiem kapitałowym, analiza ryzyka i efektywności
PublicationW artykule przedstawiono główne kategorie i rodzaje inwestycji w surowce. Cel opracowania to zbadanie czy inwestycja w Warszawski Indeks Giełdowy stanowi główny składnik optymalnego tj. cechującego się minimalnym ryzykiem portfela inwestycyjnego. Ponadto ustalono czy wspomniana inwestycja tradycyjna stanowi najważniejszy element portfela inwestycyjnego odznaczającego się najwyższą efektywnością. Stwierdzono, że wszystkie z 29 analizowanych...
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GNIAZDA PRZEDSIĘBIORCZOŚCI W STREFIE PODMIEJSKIEJ METROPOLII
PublicationProblem suburbanizacji jest wciąż aktualny w analizach rozwoju miast. Przybiera często formy spontanicznego rozlewania się miast (urban sprawl). Badacze tego problemu skupiają się przeważnie na rozwoju funkcji mieszkaniowej w strefach podmiejskich. Specyficzny charakter polskiego procesu suburbanizacji polega na równoległym rozwoju klasycznej suburbanizacji osiedleńczej oraz rozwoju mikro- oraz małych i średnich przedsiębiorstw....
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Optimization of the femtosecond laser impulse for excitation and the Spin-Orbit mediated dissociation in the NaRb Dimer
PublicationWe study the dynamics of multiple coupled states under the influence of an arbitrary time-dependent external field to investigate the femtosecond laser-driven excitation and the spin-orbit mediated dissociation in the NaRb dimer. In this process, the dimer is excited from the ground triplet state 1^3Sigma+ to the 1^3Pi state using the femtosecond laser impulse and the spin-orbit coupling between the 1^3Pi and 2^1Sigma+ states results...
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Relativistic two-dimensional hydrogen-like atom in a weak magnetic field
PublicationA two-dimensional (2D) hydrogen-like atom with a relativistic Dirac electron, placed in a weak, static, uniform magnetic field perpendicular to the atomic plane, is considered. Closed forms of the first- and second-order Zeeman corrections to energy levels are calculated analytically, within the framework of the Rayleigh–Schrödinger perturbation theory, for an arbitrary electronic bound state. The second-order calculations are...
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On Radar DoA Estimation and Tilted Rotating Electronically Scanned Arrays
PublicationWe consider DoA estimation in a monopulse radar system employing a tilted rotating array. We investigate the case of nonzero steering angles, in which case the mapping between the target’s azimuth and elevation in the global coordinate system and their counterparts in the array local coordinate system becomes increasingly nonlinear and coupled. Since estimating the azimuth using coherently integrated signals might be difficult because...
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SUBJECTIVE PERCEPTION OF MUSIC GENRES IN THE FIELD OF MUSIC INFORMATION RETRIEVAL SYSTEMS
PublicationThe aim of this paper is to evaluate the relationship between perception of music genres and subjective features of music that can be assigned to them. For this purpose a group of subjective features such as loudness, melody, rhythm, volume, instrumentation was chosen to describe music genres. A group of 30 listeners with normal hearing, ranging from 20 to 40, was created. Each sub-ject participating in listening tests was asked...
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The influence of selenium addition during germination of Brassica seeds on health-promoting potential of sprouts
PublicationThe correlation among selenium uptake, the content of bioactive compounds in sprouts, and biological activities triggered in cultured human cells by sprout extracts was investigated. Seeds of Brassica crops and rye were treated with SeO2 water solution. The selenium levels in sprouts increased from 1.0-4.1 to 53.3-382 μg/g dw with no influence on plant physiology according to the indices used. Neither the composition of glucosinolates...