排序方式： 共有69条查询结果，搜索用时 31 毫秒
41.
PLASMA HYDROPHILIZATION AND SUBSEQUENT HYDROPHOBIC RECOVERY ARE STUDIED FOR TEN DIFFERENT POLYMERS OF MICROFABRICATION INTEREST: polydimethylsiloxane (PDMS), polymethylmethacrylate, polycarbonate, polyethylene, polypropylene, polystyrene, epoxy polymer SU-8, hybrid polymer ORMOCOMP, polycaprolactone, and polycaprolactone/D,L-lactide (P(CL/DLLA)). All polymers are treated identically with oxygen and nitrogen plasmas, in order to make comparisons between polymers as easy as possible. The primary measured parameter is the contact angle, which was measured on all polymers for more than 100 days in order to determine the kinetics of the hydrophobic recovery for both dry stored and rewashed samples. Clear differences and trends are observed both between different polymers and between different plasma parameters. 相似文献
42.
The aim of this experimental study was to compare learning outcomes of students using a simulation alone (simulation environment) with outcomes of those using a simulation in parallel with real circuits (combination environment) in the domain of electricity, and to explore how learning outcomes in these environments are mediated by implicit (only procedural guidance) and explicit (more structure and guidance for the discovery process) instruction. Matched‐quartets were created based on the pre‐test results of 50 elementary school students and divided randomly into a simulation implicit (SI), simulation explicit (SE), combination implicit (CI) and combination explicit (CE) conditions. The results demonstrated that the instructional support had an expected effect on students' understanding of electric circuits when they used the simulation alone; pure procedural guidance (SI) was insufficient to promote conceptual understanding, but when the students were given more guidance for the discovery process (SE) they were able to gain significant amount of subject knowledge. A surprising finding was that when the students used the simulation and the real circuits in parallel, the explicit instruction (CE) did not seem to elicit much additional gain for their understanding of electric circuits compared to the implicit instruction (CI). Instead, the explicit instruction slowed down the inquiry process substantially in the combination environment (CE). Although the explicit instruction was able to improve students' conceptual understanding of electrical circuits considerably in the simulation environment, their understanding did not reach the level of the students in the combination environment. These results suggest that when teaching students about electricity, the students can gain better understanding when they have an opportunity to use the simulation and the real circuits in parallel than if they have only a computer simulation available, even when the use of the simulation is supported with the explicit instruction. © 2010 Wiley Periodicals, Inc. J Res Sci Teach 48: 71–93, 2011 相似文献
43.
Research in Science Education - Recent research has argued that inquiry-based science learning should be guided by providing the learners with support. The research on guidance for inquiry-based... 相似文献
44.
Sami?LehesvuoriEmail author Jouni?Viiri Helena?Rasku-Puttonen 《Journal of Science Teacher Education》2011,22(8):705-727
It is commonly believed that science teachers rely on language that allows only minor flexibility when it comes to taking
into account contrasting views and pupil thoughts. Too frequently science teachers either pose questions that target predefined
answers or simply lecture through lessons, a major concern from a sociocultural perspective. This study reports the experiences
of science student teachers when introduced to the Communicative Approach to science education drawing on dialogic teacher-talk
in addition to authoritative teacher-talk. This approach was introduced to the students in an interventional teaching program
running parallel to the student teachers’ field practice. The practical implications of this approach during initial teacher
education are the central focus of this study. The data consisting of videos of lessons and interviews indicate that the student
teacher awareness of teacher-talk and alternative communicative options did increase. Student teachers reported greater awareness
of the different functions of teacher-talk as well as the challenges when trying to implement dialogic teaching. 相似文献
45.
Sami Mahajna 《Educational studies》2017,43(3):296-311
This study examines the relation between perceived career barriers, future orientation and career decisions among young Palestinian-Israeli youth. The study employs a theoretical model that links perceived career barriers and career decisions via variables of future orientation. Three hundred eighty-eight young Palestinian-Israeli women (73.20%) and men (26.80%) participated in the study. Structural equation modelling shows that perceived ethnic discrimination is positively related to the motivational variables of future orientation, while perceived gender discrimination and childcare and family difficulties are negatively related to motivational variables. This means that perceived ethnic discrimination towards Palestinian-Israeli youths make them more inclined to perceive the value of higher education and to feel greater control over their personal accomplishments and their goals of achieving a higher education. Investment in future orientation will in all likelihood incentivise the choosing of a career path. 相似文献
46.
Learning objects (LOs), generally understood as digital learning resources shared and accessed through the Internet and reused in multiple learning contexts, have aroused enthusiasm in the field of educational technology. Although LOs offer many possibilities to change educational practices, there is a lack of empirical evidence on the effectiveness and usefulness of LOs. This paper reports results from three studies on effectiveness of LOs in various instructional settings. According to the results, there exists interaction between the effectiveness of LOs and various instructional arrangements. In order to be effective LOs require carefully designed learning environments and instructional arrangements. LOs themselves do not guarantee high‐quality learning performance and meaningful learning activities. It is the context of use together with instructional arrangements that defines the pedagogical value of LOs. 相似文献
47.
48.
M. Sami Fadali 《Journal of The Franklin Institute》2011,348(2):239-260
In this paper, we use input and output maps to develop simple procedures to obtain minimal realizations for linear continuous-time systems. The procedures developed are numerically efficient and yield explicit formulae for the state-space matrices of the realization in terms of the system parameters, notably the system eigenvalues. Both systems with distinct eigenvalues and repeated eigenvalues are treated. We also present a procedure for transforming a realization obtained through the input or output map to Jordan canonical form. The transformation matrices required to transform the realization to Jordan canonical form are specified entirely in terms of the system eigenvalues. We illustrate the results obtained with several examples. 相似文献
49.
Marja Laasonen Jenni Väre Henna Oksanen-Hennah Sami Leppämäki Pekka Tani Hanna Harno Laura Hokkanen Emmanuel Pothos Axel Cleeremans 《Annals of dyslexia》2014,64(1):1-33
In this study of the project DyAdd, implicit learning was investigated through two paradigms in adults (18–55 years) with dyslexia (n?=?36) or with attention deficit/hyperactivity disorder (ADHD, n?=?22) and in controls (n?=?35). In the serial reaction time (SRT) task, there were no group differences in learning. However, those with ADHD exhibited faster RTs compared to other groups. In the artificial grammar learning (AGL) task, the groups did not differ from each other in their learning (i.e., grammaticality accuracy or similarity choices). Further, all three groups were sensitive to fragment overlap between learning and test-phase items (i.e., similarity choices were above chance). Grammaticality performance of control participants was above chance, but that of participants with dyslexia and participants with ADHD failed to differ from chance, indicating impaired grammaticality learning in these groups. While the main indices of AGL performance, grammaticality accuracy and similarity choices did not correlate with the neuropsychological variables that reflected dyslexia-related (phonological processing, reading, spelling, arithmetic) or ADHD-related characteristics (executive functions, attention), or intelligence, the explicit knowledge for the AGL grammar (i.e., ability to freely generate grammatical strings) correlated positively with the variables of phonological processing and reading. Further, SRT reaction times correlated positively with full scale intelligence quotient (FIQ). We conclude that, in AGL, learning difficulties of the underlying rule structure (as measured by grammaticality) are associated with dyslexia and ADHD. However, learning in AGL is not related to the defining neuropsychological features of dyslexia or ADHD. Instead, the resulting explicit knowledge relates to characteristics of dyslexia. 相似文献
50.
Tugba Temiz Mustafa Sami Topcu 《European Journal of Psychology of Education - EJPE》2013,28(4):1435-1452
The purpose of this paper is to explore the relationship between preservice teachers’ (PTs) teacher efficacy beliefs and their constructivist-based teaching practices. Data were gathered through the questionnaire (Teachers’ Sense of Efficacy Scale) and the observation protocol (Reformed Teaching Observation Protocol) administered to the participants. A total number of 101 PTs (53.5 % from science education and 46.5 % from mathematics education) from a university in eastern part of Turkey participated in the study. Also, qualitative data were also used in order to clarify quantitative data. The semistructured interviews were conducted with 20 PTs who voluntarily participated in these interviews. Results showed that PTs’ constructivist-based teaching practice was positively correlated with their teacher efficacy beliefs. Also, qualitative findings confirmed that finding. To conclude, PTs with high teacher efficacy tend to employ constructivist approach in their teaching while PTs with low teacher efficacy tend to use traditional approach, lecturing in their teaching. 相似文献