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Nonlinear time-harmonic Maxwell equations in a bounded domain: Lack of compactness

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Science China Mathematics 2018年第11期61卷 1963-1970页

作者： jaroslaw Mederski Institute of Mathematics Polish Academy of Sciences Faculty of Mathematics and Computer Science Nicolaus Copernicus University

We survey recent results on ground and bound state solutions E:?→R^3 of the problem {▽(▽×E)+}λE=|E|^(P-2)E in Ω,v×E=0 on Ω on a bounded Lipschitz domain ??R^3,where?×denotes the curl operator in R^*** equation describes the propagation of the time-harmonic electric field R{E(χ)e^(iwt)}in a nonlinear isotropic material ? withλ=-μεω~2≤0,where μ andεstand for the permeability and the linear part of the permittivity of the *** nonlinear term|E|^(P-2)E with 2

关键词： time-harmonic Maxwell equations perfect conductor ground state variational methods strongly indefinite functional Nehari-Pankov manifold Brezis-Nirenberg problem critical exponent

Analogy Between Hydraulic Jump in Films Formed by Impinging Liquid Jet and Critical Flow in Internal Flows

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Journal of Thermal Science 2003年第2期12卷 171-175页

作者： jaroslaw Mikielewicz Institute of Fluid-Flow Machinery Polish Academy of SciencesGdaskPoland

Formulated are simple models for the flow in liquid film, formed by impinging jet, and a two-phase downward flow in pipe. The models are based on simplified equations of mass, momentum and energy. The solutions of such conservation equations may have regular points belonging to one integral curve only as well as turning points can be found amongst them, which refer to extreme values in the appropriate co-ordinate system. The solutions can also have singular points belonging to none or more than one integral curve. Both the turning and singular points have a clear physical meaning. They could be linked to critical flow conditions in the pipe flow or to the so-called hydraulic jump. Analogy existing between critical conditions in the pipe and the flow of liquid films formed by the liquid jet have been shown in the paper.

关键词： critical flow liquid film hydraulic jump singular points.

Some Results Connected with the Class Number Problem in Real Quadratic Fields

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Acta Mathematica Sinica,English Series 2005年第5期21卷 1107-1112页

作者： Aleksander GRYTCZUK jaroslaw GRYTCZUK Faculty of Mathematics.Computer Science and Econometrics University of Zielona Gora.65 516 Zielona Gora.Poland Institute

We investigate arithmetic properties of certain subsets of square-free positive integers and obtain in this way some results concerning the class number h（d） of the real quadratic field Q（√d）. In particular, we give a new proof of the result of Hasse, asserting that in this case h（d） = 1 is possible only if d is of the form p, 2q or qr. where p.q. r are primes and q≡r≡3（mod 4）.

关键词： The class number Real quadratic field

The impact of dielectrics on the electrical capacity, concentration, efficiency ozone generation for the plasma reactor with mesh electrodes

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Plasma Science and Technology 2018年第8期20卷 89-95页

作者： Ernest GNAPOWSKI Sebastian GNAPOWSKI jaroslaw PYTKA University College of Enterprise and Administration in Lublin Bursaki 12 20-150 Lublin Poland Fundamentals of Technology Faculty Lublin University of Technology ul. Nadbystrzycka 38 20-618 Lublin Poland Faculty of Mechanical Engineering Lublin University of Technology ul. Nadbystrzycka 36 20-618 Lublin Poland

This paper presents experimental results concerning the effect of dielectric type on ozone concentration and the efficiency of its generation in plasma reactor with two mesh *** types of dielectric solid were used in the study; glass, micanite and Kapton insulating foil. The experiments were conducted for voltage ranges from 2.3 to 13 k V. A plasma reactor equipped with two 0.3×0.3 mm^2 mesh electrodes made of acid resistant AISI 304 mesh was used in the experiments. The influence of the dielectric type on the concentration and efficiency of ozone generation was described. The resulting maximum concentration of the ozone was about 2.70–9.30 g O3 m^-3, depending on the dielectrics used. The difference between the maximum and the minimum ozone concentration depends on the dielectric used,this accounts for 70% at the variance. The reactor capacity has also been described in the paper; total Ct and dielectric capacitance Cd depending on the dielectric used and its thickness.

关键词： ozone generation efficiency dielectric mesh electrode ozone generator electrical capacity

Modeling of Flow System Dynamics

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Journal of Thermal Science 2004年第1期13卷 56-61页

作者： Andrzej Miller Krzysztof Badyda jaroslaw Dyjas Karol Miller Institute of Heat Engineering Warsaw University of TechnologyNowowiejska 2500-665WarsawPolandInstitute of Heat EngineeringWarsaw University of TechnologyNowowiejska 2500-665WarsawPolandInstitute of Heat EngineeringWarsaw University of TechnologyNowowiejska 2500-665WarsawPolandSchool of Mechanical Engineering University of Western Australia35 Stirling HighwayCrawley WA 6009Australia

This paper presents non-linear and linear models of flow system of laboratory stand (semi-industrial scale) with pressurized fluidized bed boiler. The non-linear model belongs to the class of lumped parameter models. The linear model was obtained experimentally using a novel method for design of control systems in industrial plants - MIKOZ. This study has connection with comparison of various methods of mathematical modeling of flow systems frequently encountered in power equipment.

关键词： flow system modeling lumped parameter model frequency domain identification.

Effect of spot burning of logging residues on the properties of mountain forest soils and the occurrence of ground beetles(Coleoptera, Carabidae)

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Journal of Mountain Science 2020年第1期17卷 31-41页

作者： Magdalena KACPRZYK Ewa BLONSKA jaroslaw LASOTA Department of Forest Protection Entomology and Forest ClimatologyUniversity of AgricultureAl.29 Listopada 4631-425 KrakowPoland Department of Forest Soil Science University of AgricultureAl.29 Listopada 4631-425 KrakowPoland

We investigated the relationships between dehydrogenase activity and the physicochemical properties of mountain soils over three and five years from Norway spruce(Picea abies L. Karst) logging residue spot burning and the occurrence of epigeic carabid beetles. Six study sites were utilised, including18 study plots(nine plots in a mixed coniferous mountain forest site and nine plots in a mixed broadleaf mountain forest site), with five replicate pitfall traps at each site located in southern *** samples from the organic horizon were taken for p H, organic carbon, nitrogen, base cation content,acidity and dehydrogenase activity *** beetles were monitored in weekly intervals during the period of July to August 2016. The burning of logging residues led to modified soil properties,especially the dehydrogenase activity. In all the tested variants, the activity was higher in soil samples after the burning in comparison to the control variants. We show no positive correlation between dehydrogenase activity and the number of carabid specimens. The preferences of dominant predatory hygrophilous carabids to acid habitats with weakly decomposed organic matter were proven. Simultaneously, the soil organic matter content was positively related to the carabid abundance. The significant impact of forest site conditions and the date of logging residue burning on the number of caught specimens were confirmed. In contrast, no relationships between the species richness, species diversity, mean individual biomass and spot burning effect were found. This work supports the recommendation of spruce fine woody debris utilisation by spot burning on mountain regions with rich habitats presenting moderate wet conditions and small land falls.

关键词： Fine woody debris Combustion Soil organic matter Enzyme activities Epigeic carabid beetles

Happy together？ Avoidance of conspecifics by gregarious mussels

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Current Zoology 2018年第1期64卷 53-61页

作者： Anna DZIERZYNSKA-BIALONCZYK Aleksandra SKRZYPCZAK jaroslaw KOBAK Faculty of Biology and Environmental Protection Department of Invertebrate Zoology Nicolaus CopernicusUniversity Lwowska 1 Torun 87-100 Poland

Zebra mussel Dreissena polymorpha is a Ponto-Caspian species invasive in Europe and North America, with great environmental impact. It lives byssally attached to hard substrata in large aggregations, which is often explained by its preferences for conspecifics, though direct evidence for such preferences has been rather limited so far. We studied the reactions of zebra mussels to con- specifics, hypothesizing that they may either be attracted to one another or form aggregations only in the absence of alternative attachment sites, in Experiment 1, we tested mussel tendency to detach from existing druses depending on druse size （2-25 individuals） and substratum type （soft： sand; hard： glass）. Mussels detached significantly more often on the hard substratum and from larger druses compared to soft substratum and smaller druses, respectively. This indicates that mussels tended to avoid conspecifics at high density, particularly when alternative substratum was available. In Experiment 2, we tested the responses of single mussels to distant （3 or 15cm） conspecifics （0, 3, 15 individuals per 2.51 tank） on the sandy substratum. The presence of conspecifics, regardless of their distance and density, resulted in single unattached mussels staying more often in their initial positions. Mussels did not move preferentially towards or away from the conspecifics. Thus, even on unsuitable substratum mussels were not attracted by conspecifics and probably exhibited an avoidance reaction by reducing their movement. This suggests that dense mussel aggregations are formed due to the lack of available alternative attachment sites rather than due to their preferences for conspecifics.

关键词： active detachment Dreissena polymorpha movement mussel aggregations zebra mussel.

Revisiting the nonlinear Gaussian noise model for hybrid fiber spans

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Intelligent and Converged Networks 2021年第1期2卷 30-49页

作者： Ioannis Roudas jaroslaw Kwapisz Xin Jiang Department of Electrical and Computer Engineering Montana State UniversityBozemanMT 59717USA Department of Mathematical Sciences Montana State UniversityBozemanMT 59717USA Department of Engineering and Environmental Science College of Staten IslandCity University of New YorkStaten IslandNY 10314USA

We rederive from first principles and generalize the theoretical framework of the nonlinear Gaussian noise model to the case of coherent optical systems with multiple fiber types per span and ideal Nyquist *** focus on the accurate numerical evaluation of the integral for the nonlinear noise variance for hybrid fiber *** task consists in addressing four computational aspects:(1)Adopting a novel transformation of variables(other than using hyperbolic coordinates)that changes the integrand to a more appropriate form for numerical quadrature;(2)Evaluating analytically the integral at its lower limit,where the integrand presents a singularity;(3)Dividing the interval of integration into subintervals of size and approximating the integral over each subinterval by using various algorithms;and(4)Deriving an upper bound for the relative error when the interval of integration is truncated in order to accelerate *** apply the proposed analytical model to the performance evaluation of coherent optical communications systems with hybrid fiber spans composed of quasi-single-mode and single-mode fiber *** specifically,the model is used to optimize the lengths of the optical fiber segments that compose each span in order to maximize the system *** check the validity of the optimal fiber segment lengths per span provided by the analytical model by using Monte Carlo simulation,where the Manakov equation is solved numerically using the split-step Fourier *** show that the analytical model predicts the lengths of the optical fiber segments per span with satisfactory accuracy so that the system performance,in terms of the Q-factor,is within 0.1 dB from the maximum given by Monte Carlo simulation.

关键词： nonlinear Gaussian Noise(GN)model perturbation theory hybrid fiber spans

HfO2:Eu nanoparticles excited by X-rays and UV-visible radiation used in biological imaging

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Journal of Rare Earths 2019年第11期37卷 1176-1182页

作者： jaroslaw Kaszewski jaroslaw Olszewski Julita Rosowska Bartlomiej Witkowski Lukasz Wachnicki Karolina Wenelska Ewa Mijowska Zdzislaw Gajewski Marek Godlewski Michal M.Godlewski Institute of Physics Polish Academy of SciencesAl.Lotnikow 32/4602-668 Warsaw.Poland Veterinary Research Centre Department of Large Animal Diseases with ClinicFaculty of Veterinary MedicineWarsaw University of Life Sciences一SGGVK Nowoursynowska 10002-797 WarsawPoland Department of Physiological Sciences Faculty of Veterinary MedicineWarsaw University of Life Sciences-SGGWNowoursynowska 15902-776 WarsawPoland Faculty of Chemical Technology and Engineering West Pomeranian University of Technology in Szczecinal.Piastow 4570-311 SzczecinPoland

Europium doped hafnium dioxide nanoparticles were crystallized using biologically friendly microwave hydrothermal method and employed in observation of small rodents *** solvent in synthesis is water,in consequence nanoparticles are found surrounded by thin hydroxide *** of the nanoparticles is controlled by temperature of calcination.1200℃heating causes drop of luminescence intensity,explained as damage of high symmetry surface emission centers in the *** the other hand,growth of crystallites increases intensity of X-ray and electron beam excited *** makes them promising activator in photodynamic therapy.

关键词： HfO2 Europium Scintillators Hydrothermal Nanoparticles Rare earths