Search results for " Invariance"
showing 10 items of 219 documents
Restrictions for asymmetry and polarizations of recoil in muon capture
1975
Abstract Using the helicity formalism, we discuss muon capture by targets of spin-zero. Owing to the definite neutrino helicity, three independent observables define a complete experiment. The precise relation between asymmetry α and longitudinal polarization P L of recoil, α = 1 + 2 jP L , comes only from rotational invariance. When time-reversal invariance is inserted, there is an additional restriction between the average polarization P av and the longitudinal polarization P L . On the basis of the experimental result P av = 0.43 ± 0.10 for 12 C, we predict P L = −(0.99 +0.01 −0.04 .
Positive Youth Development in Bulgaria, Italy, Norway and Romania: Testing the Factorial Structure and Measurement Invariance of the 5Cs Model
2021
This chapter applies the 5Cs model of PYD comprising competence, confidence, character, connection and caring among 1403 youth (M = 18.91 years) in Bulgaria (n = 196), Italy (n = 354), Norway (n = 564) and Romania (n = 289). These countries offer a novel and unique context to apply PYD as related comparative work with youth samples is rare across Eastern (Bulgaria and Romania), Southern (Italy) and Northern Europe (Norway). Further, Bulgaria and Romania are emerging nations following the collapse of the communism in late 1980s in contrast to Italy being a traditionally patriarchal country and social equity driven Norway. The chapter presents an empirical example that evaluates the factorial…
The Adiabatic Invariance of the Action Variables
2001
We shall first use an example to explain the concept of adiabatic invariance. Let us consider a “super ball” of mass m, which bounces back and forth between two walls (distance l) with velocity \(\boldsymbol{v}_{0}\). Let gravitation be neglected, and the collisions with the walls be elastic. If F m denotes the average force onto each wall, then we have $$\displaystyle{ F_{m}T = -\int _{\mathrm{coll.\,time}}f\,dt\;. }$$ (9.1) f is the force acting on the ball during one collision, and T is the time between collisions.
Shift and scale-invariant correlator using a radially stretched phase-only filter
1995
A radial stretching of the phase only filter depending on the energy angular distribution of the target spectrum is used to perform shift and scale invariant pattern recognition. The complex conjugate of a basic size target Fourier transform and the cumulative energy angular distribution are calculated. Then the radially stretched filter providing the same energy contribution to the correlation peak independent on the target size is prepared and used in a conventional correlator, with spherical-wave illumination. The maximum scale ratio of recognizable objects equals 1:1.5. Computer simulations and experimental results, showing the performance of the filter are presented.
Assessment of Entrepreneurial Orientation in Vocational Training Students: Development of a New Scale and Relationships With Self-Efficacy and Person…
2019
Having emerged as an important concept in the organizational field, entrepreneurial orientation has also become a key idea in the context of education. Indeed, entrepreneurial education is now one of the common objectives for education and training systems in the European Union. Despite its importance, however, there is a scarcity of valid and reliable measures for assessing entrepreneurial orientation in students. The present study aimed to address this by developing and examining the psychometric properties of the Entrepreneurial Orientation Scale (EOS). A second objective is to study the relationships between entrepreneurial orientation and gender, self-efficacy, and personal initiative.…
Item response theory and differential test functioning analysis of the HBSC-Symptom-Checklist across 46 countries
2022
Abstract Background The Symptom Checklist (SCL) developed by the Health Behaviour in School-aged Children (HBSC) study is a non-clinical measure of psychosomatic complaints (e.g., headache and feeling low) that has been used in numerous studies. Several studies have investigated the psychometric characteristics of this scale; however, some psychometric properties remain unclear, among them especially a) dimensionality, b) adequacy of the Graded Response Model (GRM), and c) measurement invariance across countries. Methods Data from 229,906 adolescents aged 11, 13 and 15 from 46 countries that participated in the 2018 HBSC survey were analyzed. Adolescents were selected using representative s…
Implementing the three-particle quantization condition including higher partial waves
2019
We present an implementation of the relativistic three-particle quantization condition including both $s$- and $d$-wave two-particle channels. For this, we develop a systematic expansion about threshold of the three-particle divergence-free K matrix, $\mathcal{K}_{\mathrm{df,3}}$, which is a generalization of the effective range expansion of the two-particle K matrix, $\mathcal{K}_2$. Relativistic invariance plays an important role in this expansion. We find that $d$-wave two-particle channels enter first at quadratic order. We explain how to implement the resulting multichannel quantization condition, and present several examples of its application. We derive the leading dependence of the …
Is there any scaling in the cluster distribution?
1994
We apply fractal analysis methods to investigate the scaling properties in the Abell and ACO catalogs of rich galaxy clusters. We also discuss different technical aspects of the method when applied to data sets with small number of points as the cluster catalogs. Results are compared with simulations based on the Zel'dovich approximation. We limit our analysis to scales less than 100 $\hm$. The cluster distribution show a scale invariant multifractal behavior in a limited scale range. For the Abell catalog this range is 15--60$\hm$, while for the ACO sample it extends to smaller scales. Despite this difference in the extension of the scale--range where scale--invariant clustering takes plac…
Assessing teacher leadership in physical education: the Spanish version of the transformational teaching questionnaire
2018
<p>Drawing from the transformational leadership theory, this study aims to translate and analyse the psychometric properties of a Spanish version of the Transformational Teaching Questionnaire (TTQ).</p><p>A cohort sample of 2107 adolescents (997 males and 1110 females) from 82 secondary schools voluntarily participated in the research.</p><p>In Study 1 ((<em>n</em> = 1066), the exploratory factor analysis informed a one-factor solution. In Study 2 (<em>n</em> = 1041), the confirmatory factor analysis showed the single-factor and the four-factor models showed satisfactory and adequate goodness of fit indices, respectively. Confirmatory …
The Italian version of the Cognitive Style Indicator and its association with decision-making preferences
2018
By adopting a more flexible view, Cools and Van den Broeck (2007) developed the Cognitive Style Indicator (CoSI) which includes three cognitive dimensions: Creating (flexible, open-ended and inventive), Knowing (emphasizing facts, details, objectivity, and rationality), and Planning (guided by preferences for certainty and well-structured information). The first aim of this research was to validate the three factor structure of the CoSI within the Italian context, whereas the second was to verify whether cognitive styles, as measured by the CoSI, accounted for individual differences in decision-making processes. Two studies were conducted using two different samples (n = 549 and n = 397). C…