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91.
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Evrikleia?Tsagala Maria?KordakiEmail author 《Education and Information Technologies》2007,12(4):281-295
This paper aims to determine the factors affecting the decisions of both male and female secondary school pupils whether or
not to pursue undergraduate studies in Computing. It is based on research conducted in Greece, on a sample of 248 pupils,
135 of whom were female. All were aged 17 and about to decide on their future undergraduate studies. Questionnaires were used,
addressing issues in the following four main categories: a) the reasons pupils chose/rejected Computing, b) how family and
friends, the media and the school environment contribute to their decision, c) how pupils perceived their future after studying
Computing and d) how pupils perceived the profile of a computer professional in terms of gender.
相似文献
Maria KordakiEmail: |
93.
A rectangular thin plate vibration model subjected to inplane stochastic excitation is simplified to a quasinonintegrable Hamiltonian system with two degrees of freedom. Subsequently a one-dimensional Ito? stochastic differential equation for the system is obtained by applying the stochastic averaging method for quasi-nonintegrable Hamiltonian systems. The conditional reliability function and conditional probability density are both gained by solving the backward Kolmogorov equation numerically. Finally, a stochastic optimal control model is proposed and solved. The numerical results show the effectiveness of this method. 相似文献
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Özlem Sila Olgun PhD 《The Teacher Educator》2013,48(2):113-125
The main purpose of this study was to investigate the effects of active learning on preservice teachers' dignity, energy, self-management, community, and awareness (DESCA) abilities, attitudes toward teaching, and attitudes toward science. Third year preservice teachers (n = 77) from two different classes were involved in the study. One intact class was assigned as the experimental group, whereas the other intact class was assigned as the comparison group. The comparison group students received the instruction by traditional teaching, and the experimental group received instruction through an active learning paradigm. DESCA abilities and attitudes were measured before and after instruction. Results revealed that there was a significant difference favoring the active learning instruction on preservice teachers' DESCA scores; however, there was no significant difference on preservice teachers' attitudes toward teaching and science. 相似文献
96.
Andreas Bauer Jan Romberg Bernhard Sch?tz 《Informatik - Forschung und Entwicklung》2005,49(3):194-205
Zur Beherrschung der komplexen vernetzten und verteilten Funktionen von Automotive-Software ist eine Beschreibung des zu erstellenden
Systems auf verschiedenen Abstraktionsebenen und schrittweise überg?nge zwischen diesen Ebenen notwendig. Neben der Definition
geeigneter Ebenen werden zur Unterstützung echtzeitkritischer Systemanteile ein einheitliches Berechnungsmodell, ebenenspezifische
Beschreibungstechniken, sowie methodische Regeln für diese Abstraktionsebenen eingeführt und in den Werkzeugprototypen AutoFocus integriert. 相似文献
97.
Wolfgang Schr?der-Preikschat Daniel Lohmann Fabian Scheler Olaf Spinczyk 《Informatik - Forschung und Entwicklung》2007,22(1):5-22
Design, implementation, and re-engineering of operating systems are still an ambitious undertaking.
Despite, or even because, of the long history of theory and practice in this field, adapting existing systems
to environments of different conditions and requirements as originally specified or assumed, in terms of
functional and/or non-functional respects, is anything but simple. Especially this is true for the embedded
systems domain which, on the one hand, calls for highly specialized and application-aware system abstractions
and, on the other hand, cares a great deal for easily reusable implementations of these abstractions.
The latter aspect becomes more and more important as embedded systems technology is faced with an innovation
cycle decreasing in length. Software for embedded systems needs to be designed for variability, and this
is in particular true for the operating systems of this domain. The paper discusses dimensions of variability
that need to be considered in the development of embedded operating systems and presents approaches that
aid construction and maintenance of evolutionary operating systems.
CR subject classification C.3; D.2.11; D.2.13; D.4.7 相似文献
98.
Elke Achtert Christian B?hm Peer Kr?ger Peter Kunath Alexey Pryakhin Matthias Renz 《Informatik - Forschung und Entwicklung》2007,15(3):179-195
The reverse k-nearest neighbor (RkNN) problem, i.e. finding all objects in a data set the k-nearest
neighbors of which include a specified query object, has received increasing attention recently. Many
industrial and scientific applications call for solutions of the RkNN problem in arbitrary metric spaces
where the data objects are not Euclidean and only a metric distance function is given for specifying
object similarity. Usually, these applications need a solution for the generalized problem where the
value of k is not known in advance and may change from query to query. In addition, many applications
require a fast approximate answer of RkNN-queries. For these scenarios, it is important to generate
a fast answer with high recall. In this paper, we propose the first approach for efficient approximative
RkNN search in arbitrary metric spaces where the value of k is specified at query time. Our approach
uses the advantages of existing metric index structures but proposes to use an approximation of the
nearest-neighbor-distances in order to prune the search space. We show that our method scales significantly
better than existing non-approximative approaches while producing an approximation of the true query
result with a high recall. 相似文献
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