1,019 research outputs found
Effectiveness of Using the Overlapping Waves Strategy During the Teaching of Geography in Acquiring the Realistic Thinking Skills and Improving the Attitudes Toward it Among the Sixth Grade Students in Jordan
The study aimed to examine the effectiveness of using the overlapping waves strategy during the teaching of geography lessons in acquiring realistic thinking skills and improving the attitudes towards geography in a sample of sixth grade students in Jordan using the quasi-experimental method. The purposive method was used to select the study sample (n = 64) students, who were randomly assigned either to the experimental group (n = 32), taught geography lessons with the overlapping waves strategy method, or the control group (n = 32), taught geography lessons with the usual method. The Realistic Thinking Skills Test (RTT) was prepared with its three dimensions, as well as the attitudes towards Geography Scale (AGS). After verifying their validity and validity, the two instruments were applied to the sample as pre post intervention. The results of the statistical analysis indicated that there were statistically significant differences at (α = 0.05) in the post test between the mean of the experimental group and the control group scores on the Realistic Thinking Skills Scale (RTS) and the Attitudes towards Geography Scale (AGS) in favor of the experimental group, indicating the efficiency of using the overlapping waves strategy used in the current study in geography teaching
Room equalization based on iterative simple complex smoothing of acoustic impulse responses
This paper presents a room equalization method based on iterative simple complex smoothing of measured acoustic impulse responses. This is useful in cases of long duration impulse responses. Corresponding time reduced impulse responses are derived which conform to perceptual principles. The smoothed impulse responses are then used to design equalization filters. Results from an audio-conferencing reverberant room using objective and subjective tests show that we can improve the measured and perceived quality of audio reproduction
Phase operators, temporally stable phase states, mutually unbiased bases and exactly solvable quantum systems
We introduce a one-parameter generalized oscillator algebra A(k) (that covers
the case of the harmonic oscillator algebra) and discuss its finite- and
infinite-dimensional representations according to the sign of the parameter k.
We define an (Hamiltonian) operator associated with A(k) and examine the
degeneracies of its spectrum. For the finite (when k < 0) and the infinite
(when k > 0 or = 0) representations of A(k), we construct the associated phase
operators and build temporally stable phase states as eigenstates of the phase
operators. To overcome the difficulties related to the phase operator in the
infinite-dimensional case and to avoid the degeneracy problem for the
finite-dimensional case, we introduce a truncation procedure which generalizes
the one used by Pegg and Barnett for the harmonic oscillator. This yields a
truncated generalized oscillator algebra A(k,s), where s denotes the truncation
order. We construct two types of temporally stable states for A(k,s) (as
eigenstates of a phase operator and as eigenstates of a polynomial in the
generators of A(k,s)). Two applications are considered in this article. The
first concerns physical realizations of A(k) and A(k,s) in the context of
one-dimensional quantum systems with finite (Morse system) or infinite
(Poeschl-Teller system) discrete spectra. The second deals with mutually
unbiased bases used in quantum information.Comment: Accepted for publication in Journal of Physics A: Mathematical and
Theoretical as a pape
Aggregation number distributions and mesoglobules in dilute solutions of diblock and triblock copolymers
We investigate the aggregation number and size distributions for
inter-molecular clusters of amphiphilic diblock and triblock copolymers in poor
solvent at very low concentrations. Diblocks and triblocks with hydrophilic
ends are shown to possess narrow distributions corresponding to formation of
monodispersed mesoglobules. Diblocks with hydrophobic ends are found to produce
inter-cluster multimers due to bridging by the hydrophilic middle blocks,
resulting in polydisperse distributions. Implications of these observations for
preparation of monodispersed nanoparticles and, potentially, understanding of
the quaternary structure of proteins are discussed.Comment: 4 pages, 4 PS figures. Accepted for publication in EP
Star-Like Micelles with Star-Like Interactions: A quantitative Evaluation of Structure Factor and Phase Diagram
PEP-PEO block copolymer micelles offer the possibility to investigate phase
behaviour and interactions of star polymers (ultra-soft colloids). A star-like
architecture is achieved by an extremely asymmetric block ratio (1:20).
Micellar functionality f can be smoothly varied by changing solvent composition
(interfacial tension). Structure factors obtained by SANS can be quantitatively
described in terms of an effective potential developed for star polymers. The
experimental phase diagram reproduces to a high level of accuracy the predicted
liquid/solid transition. Whereas for intermediate f a bcc phase is observed,
for high f the formation of a fcc phase is preempted by glass formation.Comment: 5 pages, 4 figures, PRL in pres
Il processo di designazione dei vescovi nelle Chiese Orientali
O Codex Canonum Ecclesiarum Orientalium legisla sobre o processo ordinário (e extraordinário) para a designação dos bispos das Igrejas orientais e sobre o respectivo
método, que é duplo: por lista ou por eleição directa. Exprimindo opiniões e reflexões pessoais, que julga úteis e oportunas, o autor faz-se eco de observações, queixas, reivindicações e protestos das Igrejas orientais sobre este processo canónico.The Codex Canonum Ecclesiarum Orientalium legislates on the ordinary (and extraordinary) process for the designation of bishops in the oriental Churches and on the respective method, which is twofold: by list or by direct election. By expressing
personal opinions and reflections, felt to be useful and opportune, the author makes
himself an echo of observations, complaints, demands and protests in oriental Churches with regard to this canonical process
Statistical properties of Klauder-Perelomov coherent states for the Morse potential
We present in this paper a realistic construction of the coherent states for
the Morse potential using the Klauder-Perelomov approach . We discuss the
statistical properties of these states, by deducing the Q- and P-distribution
functions. The thermal expectations for the quantum canonical ideal gas of the
Morse oscillators are also calculated
The Moyal Bracket in the Coherent States framework
The star product and Moyal bracket are introduced using the coherent states
corresponding to quantum systems with non-linear spectra. Two kinds of coherent
state are considered. The first kind is the set of Gazeau-Klauder coherent
states and the second kind are constructed following the Perelomov-Klauder
approach. The particular case of the harmonic oscillator is also discussed.Comment: 13 page
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