135 research outputs found
Software Holography: Interferometric Data Analysis for the Challenges of Next Generation Observatories
Next generation radio observatories such as the MWA, LWA, LOFAR, CARMA and
SKA provide a number of challenges for interferometric data analysis. These
challenges include heterogeneous arrays, direction-dependent instrumental gain,
and refractive and scintillating atmospheric conditions. From the analysis
perspective, this means that calibration solutions can not be described using a
single complex gain per antenna. In this paper we use the optimal map-making
formalism developed for CMB analyses to extend traditional interferometric
radio analysis techniques--removing the assumption of a single complex gain per
antenna and allowing more complete descriptions of the instrumental and
atmospheric conditions. Due to the similarity with holographic mapping of radio
antenna surfaces, we call this extended analysis approach software holography.
The resulting analysis algorithms are computationally efficient, unbiased, and
optimally sensitive. We show how software holography can be used to solve some
of the challenges of next generation observations, and how more familiar
analysis techniques can be derived as limiting cases.Comment: in revie
Differences in Physical Activity between Non-overweight, Overweight and Obese Children
The purpose of the study was to find out differences in moderate to vigorous physical activity among non-overweight, overweight and obese children, and between boys and girls. The sample included 364 children (179 boys and 185 girls), aged 6.4 years (±0.3 SD). Physical activity was assessed by 7-day questionnaire. Age adapted BMI was used as overweight and obesity indicator. The children were divided into non-overweight, overweight and obese groups. It was found out, that there are significant differences in non-overweight, overweight and obese children (p<0.05). Boys were significantly (p< 0.05) less moderate to vigorous physical active than girls, especially in indoor activities. There were also significant differences (p<0.05) in moderate to vigorous physical activity among non-overweight and obese boys and among overweight and obese boys in weekends and total weekly activity. In girls there are significant differences (p<0.05) in nonoverweight, overweight and groups in weekends and total weekly activity. It is possible to conclude, that obese boys and overweight and obese girls, are prone to less physical activity
FACTORS AFFECTING EDUCATIONAL AND VOCATIONAL PLANS OF FOSTER CARE CHARGES
The objective of a foster care is to ensure that a child who is deprived of the adequate care from the biological family lives in the adequate environment. People who deal with Foster care responsibilities are bound to ensure a proper care to a child as well as prepare this child to future life, including vocational one. Thus, essential are educational and vocational plans of charges since they affect the process of gaining the autonomy by a youngster. The three actions: firstly, analysing the literature, secondly, doing researches in bialski poviat, thirdly, conducting a narrative questionnaire with an educator who simultaneously holds the responsibility for teaching charges autonomy, these three are supposed to identify factors that affect educational and vocational plans that foster care charges have. Factors that play significant role are as follows: a kind of foster care (family-run children houses versus educational care centres), the influence exerted by a subject and people who are supposed to support the process of gaining autonomy (foster care provider, tutor, pedagogue, educator responsible for teaching autonomy), personal characteristics (for example low self-esteem, lack of willingness and motivation to learn, lack of skills) and environmental factors (impact of dysfunctional family environment, peer environment, local environment).
Povezanost akademskih postignuća i tjelesnoga fitnesa kod djece u predadolescentnoj dobi
The purpose of the study was to determine whether students differ in terms of
their physical fitness according to their academic achievements in mathematics,
language (Slovene) and PE. The sample comprised 467 participants: 250 males and
217 females. In order to assess physical fitness levels, eight different tests from the
Eurofit test battery were conducted. The academic performance of children was
defined on the basis of three criteria: final grades in mathematics, final grades in
Slovene language and final grades in the subject of sports. An independent t-test
and a multiple regression analysis were performed to determine the relationship
between various physical fitness tests and academic achievement. The most
important finding of our study is that physical fitness is related to academic
achievement in preadolescent children. Children with better academic achievements
performed better in most physical fitness tests than peers who had poorer academic
performance.Svrha studije bila je utvrditi razlikuju li se djeca u pogledu tjelesnoga fitnesa u
skladu s njihovim akademskim uspjehom iz matematike, jezika (slovenski jezik) i
tjelesne i zdravstvene kulture. Uzorak je obuhvaćao 467 sudionika: 250 dječaka i
217 djevojčica. Kako bi se procijenila razina tjelesnoga fitnesa, provedeno je osam
različitih testova iz testne baterije Eurofit. Akademski uspjeh djece definiran je na
temelju tri kriterija: završne ocjene iz Matematike, završne ocjene iz Slovenskog
jezika i završne ocjena iz Tjelesne i zdravstvene kulture. Provedeni su neovisni t-test
i višestruka regresijska analiza kako bi se utvrdio odnos između različitih testova
tjelesnoga fitnesa i akademskoga uspjeha. Najvažniji nalaz našega istraživanja jest da
je tjelesni fitnes povezan s akademskim uspjehom kod djece u predadolescentnoj dobi.
Djeca s boljim akademskim uspjehom pokazala su bolje rezultate na većini testova
tjelesnoga fitnesa u usporedbi s vršnjacima koji su imali slabiji akademski uspjeh
Literatura i mistyka. Przyczynek do badań nad wyobraźnią poetycką Juliusza Słowackiego
The topic of the article is the poetical reaction of Juliusz Słowacki to the crisis of culture in the early 40s of the 19th century. Epiphanic awareness of the theological dimension of the space has beenconfronted with conviction about the disintegration of language, which has lost the ability to give the appearance of reality. Słowacki expressed confidence that the source of his mystical vision of the universe is ideal perception. Therefore, description of the mystical worldview requires the new concept art, the project of original model of the poetic language with the symbolic imagination in the foreground. Interpretation of the “Genesis” philosophy cannot be based on human experience – cannot be expressed in adequate and direct performances. In the discussed issue, discursive language is not suitable, because of the loosening of categories traditionally used to describe reality. Thus, Słowacki was forced to use ambiguous signs, which would allow one to understand the sense of revelation.Sednem rozważań jest poetycka reakcja Juliusza Słowackiego na stan wyczerpania kultury, którego poeta doświadczył na początku lat 40. XIX wieku. Uzyskana na drodze epifanii świadomość teleologicznego wymiaru kosmosu została zestawiona z dominującym wówczas przekonaniem o rozpadzie języka – Logos stracił zdolność dawania pozorów rzeczywistości. Słowacki wyraził pewność, że sposób, w jaki odczuł utajoną dotychczas wizję uniwersum, utożsamia percepcję idealną. Deskrypcja mistycznego światopoglądu wymagała zatem stworzenia koncepcji sztuki, która zmieni pisarstwo w posłannictwo, a świat „glansowanych rękawiczek” zastąpi ideą nowej wiary. Ramy tego ambitnego projektu wyznacza oryginalny model języka, którego kołem zamachowym jest wyobraźnia symboliczna. Wykładnia filozofii genezyjskiej nie może podlegać ludzkiemu doświadczeniu – nie daje się wyrazić w przedstawieniach adekwatnych i bezpośrednich. Język dyskursywny nie spełnia w tym przypadku zadania poznawczego ze względu na rozchwianie kategorii tradycyjnie używanych do opisu rzeczywistości. Słowacki był zmuszony więc odwołać się do znaków, które przez swoją niejednoznaczność oddadzą migotliwy, przepełniony sprzecznościami sens objawienia
Rodzinna piecza zastępcza nad dzieckiem – formy pomocy i wsparcia w codziennym funkcjonowaniu oraz w sytuacjach trudnych – kryzysowych
Family foster care is a form of temporary care for children who, for various reasons, cannot grow up in a biological family. Foster families have a variety of tasks to fulfill, resulting not only from the current custody of the child, but also from the need for extensive compensation for the general developmental deficiencies of the child placed in it. The purpose of the article is to present the possibilities and forms of support directed to children residing in foster families who have experienced various difficult situations and crisis events in their biological families, as well as general assistance that can be obtained by foster families in which difficult crisis situations arise concerning daily functioning.Family foster care is a form of temporary care for children who, for various reasons, cannot grow up in a biological family. Foster families have a variety of tasks to fulfill, resulting not only from the current custody of the child, but also from the need for extensive compensation for the general developmental deficiencies of the child placed in it. The purpose of the article is to present the possibilities and forms of support directed to children residing in foster families who have experienced various difficult situations and crisis events in their biological families, as well as general assistance that can be obtained by foster families in which difficult crisis situations arise concerning daily functioning
Ionospheric Power-Spectrum Tomography in Radio Interferometry
A tomographic method is described to quantify the three-dimensional
power-spectrum of the ionospheric electron-density fluctuations based on
radio-interferometric observations by a two-dimensional planar array. The
method is valid to first-order Born approximation and might be applicable to
correct observed visibilities for phase variations due to the imprint of the
full three-dimensional ionosphere. It is shown that not the ionospheric
electron density distribution is the primary structure to model in
interferometry, but its autocorrelation function or equivalent its
power-spectrum. An exact mathematical expression is derived that provides the
three dimensional power-spectrum of the ionospheric electron-density
fluctuations directly from a rescaled scattered intensity field and an incident
intensity field convolved with a complex unit phasor that depends on the w-term
and is defined on the full sky pupil plane. In the limit of a small field of
view, the method reduces to the single phase screen approximation. Tomographic
self-calibration can become important in high-dynamic range observations at low
radio frequencies with wide-field antenna interferometers, because a
three-dimensional ionosphere causes a spatially varying convolution of the sky,
whereas a single phase screen results in a spatially invariant convolution. A
thick ionosphere can therefore not be approximated by a single phase screen
without introducing errors in the calibration process. By applying a Radon
projection and the Fourier projection-slice theorem, it is shown that the
phase-screen approach in three dimensions is identical to the tomographic
method. Finally we suggest that residual speckle can cause a diffuse intensity
halo around sources, due to uncorrectable ionospheric phase fluctuations in the
short integrations, which could pose a fundamental limit on the dynamic range
in long-integration images.Comment: 8 pages; Accepted for publication in Ap
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