Wyniki wyszukiwania - Biblioteka Nauki

1

Bordism of oriented 5-manifolds with T-structure and polarization

100%

Mikrut P.

Colloquium Mathematicum

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1999

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tom 79

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nr 2

161-184

2

Aspects of Geometric Quantization Theory in Poisson Geometry

100%

Vaisman I.

Banach Center Publications

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2000

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tom 51

|

nr 1

283-292

EN

This is a survey exposition of the results of [14] on the relationship between the geometric quantization of a Poisson manifold, of its symplectic leaves and its symplectic realizations, and of the results of [13] on a certain kind of super-geometric quantization. A general formulation of the geometric quantization problem is given at the beginning.

3

Fox News and the polarization of attitudes in the U.S.

100%

Wanta W.

Central European Journal of Communication

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2008

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tom 1

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nr 1

111-121

EN

Mass media in the United States have historically evolved through three stages in which the content is aimed at the elites, then the masses, then specialized audiences. This evolution has recently been taking place within the news media, where Fox News is now being aimed at conservative viewers. The effect of the conservative content of Fox News on its viewership was examined. Findings from a survey show that Fox viewers are more polarized than other news consumers on several issues. Whether they watched Fox News or some other news program, however, the respondents consist- ently felt that the media were between good and fair in their coverage. Fox News viewers seem to be relatively satisfi ed with the news content they receive – or at least as satisfied as respondents who get their information from other sources.

4

Dobrobyt i jakość życia: badania w Polsce i za granicą

100%

Ostasiewicz W.

Śląski Przegląd Statystyczny

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2013

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nr 11(17)

229-243

EN

This paper contains a short version of my presentation in two conferences. One of them “International endeavours to study quality of life”, took place in Wrocław on 7 March 2011, the second one, “Quality of life as a subject of statistical survey”, took place in Poznań on 18 April 2012. This paper also includes a short review of selected Polish publications.

5

Information Content in Linear Dichroism Spectra

100%

Thulstrup P. W.

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2008

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tom Vol. 82, nr 4

901-920

EN

Spectroscopy with linearly polarized light on aligned samples (LD spectroscopy) is a useful technique that may greatly enhance the possibilities for determining sample structure, making spectral assignments, and several other tasks, generally based on a determination of transition moment directions. However, the technique does not provide the same amount of information in all cases; this depends strongly on the molecular symmetry. The almost ideal case is that of D2h, D2, or C2v symmetry, when only 3 different (perpendicular) transition moment directions are possible. When the molecular symmetry decreases, the information that may be obtained becomes less precise. If the molecule has a plane of symmetry left, the transition moment may be located perpendicular to the symmetry plane or at any direction in the plane, and much useful information may still be extracted. In the case of a molecule with no symmetry at all the information that can be obtained often becomes highly qualitative, unless special information happens to be available. Unfortunately, this severe limitation is sometimes overlooked when low-symmetry molecules are studied, and the spectra are evaluated the same way spectra for symmetrical molecules are. This is an obvious source of error, and conclusions based on such an analysis are hardly reliable. In this paper, the spectroscopic technique, assumptions commonly made, and the mathematical treatment of IR and UV spectra are briefly summarized for different molecular symmetries. This is illustrated by a few examples, including new IR LD spectra of limonene, a very difficult, low symmetry case.

6

Multiple polarized beam interferometers for array generation with improved efficiency

100%

Patra A. S. , Khare A.

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2008

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tom Vol. 38, nr 3

495-502

EN

A highly efficient multiple polarized beam interferometer for the generation of hexagonal array is reported. An expression for the intensity distribution is worked out using Jones' calculus and computed pattern is compared with the experimental results. The array pattern could be scanned over large longitudinal distances without loss of distortion. Fringe visibility of interferograms has been studied as a function of relative state of polarization of the interfering beams. Some of the potential applications of such arrays are also proposed.

7

Influence of the Brownian movement on the motion of nanoand micro-particles in the inhomogeneous optical field

100%

Zenkova C. Y. , Gorsky M. P. , Soltys I. V. , Angelsky P. O.

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tom Vol. 20, No. 3

247-254

EN

The motion of light scattering particles of the Mie and Rayleigh micro- and nano-range type in the inhomogeneously-polarized optical field, with allowance made for the Brownian movement, is analysed in the paper. The spatial modulation of polarization in the observation plane determines the spatial modulation of the volume energy density. That is why the velocity and the resulting optical force, which cause the motion of the testing particles, change according to the degree of coherence of the interacting fields. The influence of the forces which arise in the viscous medium and cause the Brownian movement upon the mechanisms of manipulating and trapping testing particles by the optical field is studied.

8

Amplification of radiation in atomic vapor induced by a linearly polarized laser radiation

100%

Movsisyan M. , Shmavonyan S. , Papoyan A.

Open Physics

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2011

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tom 9

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nr 4

948-955

EN

We present the results of spectroscopic and polarization studies of dilute rubidium vapor exposed to a single-frequency linearly polarized diode laser radiation in a spectral range of atomic D2 line. We report the origin of a circularly polarized radiation on V-type transitions of 87Rb F g = 2 → F e = 3 and 85Rb F g = 3 → F e = 4, and amplification of this radiation in backward direction caused by a partial population inversion among magnetic sublevels of the ground and excited levels. This is confirmed experimentally by high directivity of backward radiation, absence in its spectrum of 85Rb F g = 2 → F e = 1 (Λ-type) radiation, as well as by different nature of intensity dependences of backward and fluorescence radiations.

9

ВИВЧЕННЯ ЯВИЩА ПОЛЯРИЗАЦІЇ В ПРОЦЕСІ ВИКОНАННЯ ЛАБОРАТОРНИХ РОБІТ

100%

Аврамчук О.

Педагогічні науки: теорія, історія, інноваційні технології

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2017

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nr 2(66)

3-11

EN

The article discusses the study of the topic “Polarization” in the process of implementation of laboratory works of the students of higher military education institutions. The results of the study of modern physics teaching and the issues of rational use of teaching time has shown that it is expedient to introduce innovations in the methodology of conducting those activities in which the students acquire practical skills in professional direction from the first years of study in higher school. The use of one of the classes of experimental and practical components in the study of one topic in the process of training of students clearly indicates integration of fundamental and professional components of training of the future military specialists. The process of the combination of the practical and experimental component of the work in the framework of laboratory classes on the topic “Polarization” is described; it is studied in the second semester. To explore this phenomenon cadets are offered three laboratory works: - laboratory work № 26, under the theme “Experimental verification of law of Malus”, the goal of the study was to explore the phenomenon of polarization in the process of experimental verification of law of Malus; - laboratory work № 27, under the theme “Study of polarization of light upon reflection from a dielectric surface”, the aim of this work is to investigate experimentally the degree of polarization of light reflected at the interface of two dielectrics, and to verify the Brewster’s law; - laboratory work № 28, the theme of which is “the study of the phenomenon of rotation of plane of polarization of light”, the aim of the study was to investigate the natural phenomenon of rotation of polarized light in optically active substances. Before they perform the work, the students should repeat the following theoretical questions: - for the laboratory work № 26: 1. The phenomenon of polarization of electromagnetic waves. Natural and polarized light. 2. Methods of obtaining polarized light. The physical nature of the action of the polarization devices. Law of Malus. - laboratory work № 27:1. The concept of light polarization and its types.2. Law Of Malus. The Law Of Brewster. - laboratory work №28:1. Podine premeasurement. The natural rotation of the plane of polarization. 2. Magnetic rotation of the plane of polarization. 3. The Faraday Effect. According to the tasks and equipment of each laboratory work the study of the topic is weighty fact that laboratory works vary by complexity of implementation; therefore, students with low levels of training are offered the laboratory work № 26; and work № 27 and № 28 are proposed for the students with a high level of knowledge of the discipline, because even the equipment itself requires discipline and responsibility of the students in the deposition and withdrawal of the installation to its original state (especially working with goniometer – laboratory work № 27 and accuracy with the polarimeter cuvettes and the appropriate concentrations, laboratory work №28). Each of the works serves a separate theoretical introduction and an appropriate order of execution. The order of execution of each job was individually taught in all workplaces. After performing the experimental part of the work the teacher gives the students a checklist of questions for which they should know answers during the oral defense.

10

Polarization Characteristics and Cathodic Hydrogenation of TbNi4.8M0.2 (M= Sb, Bi, Al) Alloys in Strong Alkaline Solution

88%

Kukuła I. , Bala H. , Giza K. , Pavlyuk V. V. , Marciniak B.

|

2010

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tom Vol. 55, iss. 1

79-83

EN

In this work an initial characterisation of electrochemical polarization behaviour of TbNi4.8M0.2 (M = Sb, Bi or Al) type alloys in strong alkaline solution has been carried out. It was established that all the tested TbNi4.8M0.2 alloys passivated in 6 M KOH. It is shown that the presence of Bi in the hydrogenated alloy causes distinct increase of anodic current in passive rangę and thus worsens the passivating properties of the alloy. Polarization resistance of the tested alloys measured at potentials close to eąuilibrium potential of H20/H2 system allowed to evaluate exchange current densities for hydrogen absorption-desorption process. Absorption efficiency of cathodically evolved hydrogen on TbNi4.8M0.2 type alloys in strong alkaline solution has been investigated at p = 1 atm by the potentiostatic techniąue. The hydrogen charging and discharging experiments have shown that the tested alloys absorb hydrogen effectively in strong alkaline solution, and TbNi4.8Bi0.2 alloy is capable to absorb the highest ąuantities of cathodic hydrogen.

PL

W pracy dokonano elektrochemicznej charakterystyki polaryzacyjnej stopów typu TbNi48M0.2 (M = Sb, Bi lub Al) w środowisku silnie alkalicznym. Stwierdzono, że wszystkie badane stopy TbNi48M0.2 pasywują się w 6 M KOH. Obecność bizmutu w badanym stopie prowadzi do wzrostu gęstości prądów anodowych, a tym samym pogarsza odporność korozyjną stopu. Opór polaryzacji badanych stopów wyznaczony dla potencjału bliskiego potencjałowi równowagowemu układu H20/H2 pozwolił ocenić gęstości prądów wymiany dla procesu absorpcji/desorpcji wodoru. Stosując potencjostatyczną metodę pomiaru, badano absorpcję katodowo wydzielanego wodoru przez wyżej wymienione stopy w silnie alkalicznym roztworze. Pomiary ładowania i rozładowania pokazują, że wszystkie stopy TbNi48M0.2 absorbują wodór, przy czym największą efektywnością pochłaniania katodowego wodoru pod ciśnieniem 1 atm charakteryzuje się TbNi4;8Bi0,2.

11

Structural, dielectric, electrical and piezoelectric properties of Ba4SrRTi3V7O30 (R=Sm, Dy) ceramics

88%

Sahoo P. , Panigrahi A. , Patri S. , Choudhary R.

Open Physics

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2008

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tom 6

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nr 4

843-848

EN

Polycrystalline samples of Ba4SrRTi3V7O30 (R=Sm and Dy), members of the tungsten-bronze family, were prepared using a high-temperature, solid-state reaction technique and studied their electrical properties (using complex impedance spectroscopy) in a wide range of temperature (31–500°C) and frequency (1 kHz-1 MHz). Preliminary structural (XRD) analyses of these compounds show the formation of single-phase, orthorhombic structures at room temperature. The scanning electron micrographs (SEM) provided information on the quality of the samples and uniform distribution of grains over the entire surface of the samples. Detailed studies of the dielectric properties suggest that they have undergone ferroelectric-paraelectric phase transition well above the room temperatures (i.e., 432 and 355°C for R= Sm and Dy, respectively, at frequency 100 kHz). Measurements of electrical conductivity (ac and dc) as a function of temperature suggest that the compounds have semiconducting properties much above the room temperature, with negative temperature coefficient of resistance (NTCR) behavior. The existence of ferroelectricity in these compounds was confirmed from a polarization study.

12

Evolution of the polarization of electromagnetic waves in weakly anisotropic inhomogeneous media - a comparison of quasi-isotropic approximations of the geometrical optics method and the Stokes vector formalism

88%

Kravtsov Y. , Bieg B.

Open Physics

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2008

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tom 6

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nr 3

563-568

EN

The main methods describing polarization of electromagnetic waves in weakly anisotropic inhomogeneous media are reviewed: the quasi-isotropic approximation (QIA) of geometrical optics method that deals with coupled equations for electromagnetic field components, and the Stokes vector formalism (SVF), dealing with Stokes vector components, which are quadratic in electromagnetic field intensity. The equation for the Stokes vector evolution is shown to be derived directly from QIA, whereas the inverse cannot be true. Derivation of SVF from QIA establishes a deep unity of these two approaches, which happen to be equivalent up to total phase. It is pointed out that in contrast to QIA, the Stokes vector cannot be applied for a polarization analysis of the superposition of coherent electromagnetic beams. Additionally, the ability of QIA to describe a normal modes conversion in inhomogeneous media is emphasized.

13

Structural and electrical properties of KCa2Nb5O15 ceramics

88%

Behera B. , Nayak P. , Choudhary R.

Open Physics

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2008

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tom 6

|

nr 2

289-295

EN

A polycrystalline sample of KCa2Nb5O15 with tungsten bronze structure was prepared by a mixed oxide method at high temperature. A preliminary structural analysis of the compound showed an orthorhombic crystal structure at room temperature. Surface morphology of the compound shows a uniform grain distribution throughout the surface of the sample. Studies of temperature variation on dielectric response at various frequencies show that the compound has a transition temperature well above the room temperature (i.e., 105°C), which was confirmed by the polarization measurement. Electrical properties of the material have been studied using a complex impedance spectroscopy (CIS) technique in a wide temperature (31–500°C) and frequency (102–106 Hz) range that showed only bulk contribution and non-Debye type relaxation processes in the material. The activation energy of the compound (calculated from both the loss and modulus spectrum) is same, and hence the relaxation process may be attributed to the same type of charge carriers. A possible ‘hopping’ mechanism for electrical transport processes in the system is evident from the modulus analysis. A plot of dc conductivity (bulk) with temperature variation demonstrates that the compound exhibits Arrhenius type of electrical conductivity.

14

Kapitalizm a kwestia miejska

75%

Jałowiecki B.

|

tom LXVII (67)

|

nr 1

9-23

PL

W przekształceniach polskich miast w ostatnim ćwierćwieczu istotną rolę odgrywa renta gruntowa, a jednym z najważniejszych aktorów wytwarzania przestrzeni stali się deweloperzy. W rezultacie następuje prywatyzacja przestrzeni i polaryzacja przestrzenno-społeczna.

EN

In the transformation of Polish cities in the last quarter of a century, ground rent has played an important role, and developers have emerged as one of the most important actors in the production of space. As a result, we are witnessing space privatization and spatial-social polarization in cities.

15

Transmisja światłowodowa wykorzystująca polaryzację światła

75%

Perlicki K.

|

2009

|

tom z. 171

3-144

PL

W niniejszej publikacji przedstawiono badanie wpływu liniowych zjawisk polaryzacyjnych na jakość pracy wybranych systemów telekomunikacji światłowodowej, wykorzystujących transmisję sygnałów optycznych w wielu stanach polaryzacji światła. W ramach pracy zreferowano, jak zaprojektowano, wykonano i przebadano statystyczny symulator dyspersji polaryzacyjnej i tłumienia zależnego od polaryzacji oraz deterministyczny symulator tłumienia zależnego od polaryzacji. Opisano przebadany wpływ zjawisk polaryzacyjnych na jakość pracy dwukanałowego systemu ze zwielokrotnieniem polaryzacyjnym. Przedstawiono zasadę działania i właściwości opracowanego systemu ze zwielokrotnieniem polaryzacyjnym, w którym wykorzystuje się trzy kanały polaryzacyjne. W ramach pracy opisano opracowany i przebadany nowy sposób odbioru sygnałów optycznych w systemie z kluczowaniem polaryzacji. Wykorzystano w nim skrętność i krzywiznę krzywej przestrzennej, na której są zlokalizowane stany polaryzacji odbieranych sygnałów optycznych. Zreferowano przebadanie wpływu zjawisk polaryzacyjnych na działanie opracowanej metody.

EN

Low cost polarization mode dispersion and polarization dependent loss emulators were designed and validated. The designed emulators were applied to mimic the polarization effects of real optical fiber links. Impact of the polarization effects on Polarization Division Multiplexing and single channel transmission system was evaluated. A method of multiplexing and demultiplexing three polarization optical channels in order to triple the capacity in the optical fiber links was proposed and experimentally implemented. There followed a proposed solution to the problem of recovering and tracking the signal configuration at the receiver side for digital optical transmission systems employing the polarization shift keying technique. The tracking algorithm for optical signal configuration was based on analysis of torsion and curvature of three dimensional curve segments. Impact of polarization effects on the presented method was investigated.

16

Households’ Saving Mobility in Poland

75%

Liberda B. , Pęczkowski M.

Statistics in Transition new series

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2013

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tom 14

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nr 2

273-286

EN

In this paper we examine the mobility of Polish households with regard to saving rates during the years 2007-2010 and compare it with the households’ saving mobility during the years 1997-2000. The analysis for 2007-2010 is based on the household budget panel data from three panels of 15,000 Polish households selected by authors for the years 2007-2008, 2008-2009 and 2009-2010 from the Household Budget Surveys. We use the Markov mobility matrix and estimate the long-term ergodic distribution of households according to the saving rates. Our results show that the long-term households’ distribution reveals a tendency towards polarization of households with regard to saving rates. Comparing the results for 2007-2010 with the authors’ previous research on the households’ saving mobility for a decade earlier during 1997-2000, we prove that between the years 1997-2000 and 2007-2010 the long-term change in the distribution of households was asymmetrical toward the highest saving rate groups. This helps to explain why Polish households could maintain positive and rising savings during the highly uncertain period of the financial crisis in 2007-2010.

17

Utilization of measurements of electrode linear polarization resistance for initial verification of steel corrosion inhibitors for the neeeds of steel plant cooling systems

75%

Kozik C.

|

2007

|

tom Vol. 28, z. 2

233-243

EN

A method has been developed of initial assessment of the effectiveness of steel corrosion inhibitors in cooling water, in order to determine the manner of water inhibition in a pilot cycle or directly in the industrial cycle. Electrode linear polarizations have been measured in the range of +/-(10 - 20) mV in series, 8 model stands each, with various conditions of water preparation. The examination of samples of water from the cooling systems of a continuous caster of one of steel plants indicated that there is a possibility of determining the protective properties of inhibitors within 20 h - which has been confirmed with direct gravimetric measurements.

PL

Opracowano metodę wstępnej oceny efektywności inhibitorów korozji stali w wodzie chłodzącej, w celu określenia sposobu inhibitowania wody w obiegu pilotowym lub bezpośrednio w obiegu przemysłowym. Wykorzystano pomiary oporności polaryzacji liniowej elektrod w zakresie napięć +/-(10 - 20) mV w seriach po 8 stanowisk modelowych z różnymi warunkami przygotowania wody. Badania próbek wody z obiegów chłodzących urządzenia do ciągłego odlewania stali jednej z hut wskazały na możliwość wyznaczania właściwości ochronnych inhibitorów w okresie 20 h, co potwierdzono bezpośrednimi pomiarami grawimetrycznymi.

18

Indoor optical free space networks - reflectivity of light on building materials

75%

Vitasek J. , Koudelka P. , Latal J. , Dostal F. , Sokansky K.

|

2011

|

tom R. 87, nr 4

41-44

EN

Over the past decade rapid development happened in the field of communication technologies based on optical fibers. Over the past decade rapid development happened in the field of communication technologies based on an optical fibers. These technologies become dominant in the field of the last mile networks as well (WDM-PON, GePON, EPON, etc). As an alternative to the last mile networks can be considered the socalled free space optical networks (FSO). Currently, diffusion systems make an interesting concept into the future. They use secondary sources -building materials inside the room. Therefore it is necessary to pay attention to an issue of the light reflectivity on building materials.

PL

Ostatnia dekada przyniosła, w dziedzinie optoelektroniki, szybki rozwój technologii tele-informatycznych opartych na światłowodach. Technologie te zyskują znaczną popularność w sieciach ostatniej mili (WDM-PON, GePON, EPON, itd.). Jako alternatywę w stosunku do sieci ostatniej mili można przyjąć optyczne sieci bezwłóknowe (FSO). Z punktu widzenia przyszłości systemy dyfuzyjne prezentują się jako ciekawa koncepcja. Korzystają one ze źródeł wtórnych - materiałów budowlanych wewnątrz pomieszczeń, dlatego koniecznym jest poświęcenie uwagi problematyce wpływu odbić światła na materiałach budowlanych.

19

The behavior of the Poynting vector in the area of elementary polarization singularities.

75%

Mokhun I. , Khrobatin R. , Mokhun A. , Viktorovskaya J.

|

2007

|

tom Vol. 37, nr 3

261-277

EN

The behavior of the Poynting vector in the area of elementary polarization singularities withone or two C-points, which are bounded by regular shape s-contour is considered. It has been shown that C-points are associated with the "vortex" kind singularities of the averaged transversal component of the Poynting vector if the handedness factor and topological charge of C-point are characterized by different signs. "Passive" Poynting singularities arise in the area if the signs are the same. It has been shown that the positions of the Poynting singularities shift relatively to the C-points under the phase and amplitude asymmetry of orthogonal components of the resulting field. The results of the computer simulation are presented.

20

Equality cases for condenser capacity inequalities under symmetrization

75%

Betsakos D. , Pouliasis S.

Annales Universitatis Mariae Curie-Skłodowska, sectio A – Mathematica

|

2012

|

tom 66

|

nr 2

EN

It is well known that certain transformations decrease the capacity of a condenser. We prove equality statements for the condenser capacity inequalities under symmetrization and polarization without connectivity restrictions on the condenser and without regularity assumptions on the boundary of the condenser.