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991.
992.
An important purpose of higher social work education is to guide students to acquire and develop social-communicative competencies. The purpose of this study was to investigate the role students’ personality characteristics, self-perceived communicative competence and learning conceptions play in the acquisition and development of social-communicative competencies. We designed and tested a hypothetical model on the student-related variables – self-perceived communicative competence, learning conceptions and reported learning activities regarding communication – in relation to performance scores. We were interested in developmental trends in the above mentioned variables. We also wanted to gain insight into the relationships among the variables. The study was set up according to a longitudinal, within-subjects design in order to study intra-individual changes. One-hundred and twenty-three first-year social-work students participated in this study. Many changes were found in students characteristics, reported deployed learning activities and study results during their first academic year. Except for confidence in “showing sympathy”, which was already relatively high at the beginning of the study, all scores on aspects of students’ self-perceived social-communicative competence increased. Assessment scores on comparable communication tests also increased significantly. Extraversion and emotional stability were the only two personality characteristics, which seemed rather stable. Agreeableness decreased while autonomy increased continuously during the first academic year. It seemed to be possible to set up a model, which may serve as a starting point for further research into the development of social-communicative competence.  相似文献   
993.
This paper investigates the role of tools in the formation of mathematical practices and the construction of mathematical meanings in the setting of a telecommunication organization through the actions undertaken by a group of technicians in their working activity. The theoretical and analytical framework is guided by the first-generation activity theory model and Leont’ev’s work on the three-tiered explanation of activity. Having conducted a 1-year ethnographic research study, we identified, classified, and correlated the tools that mediated the technicians’ activity, and we studied the mathematical meanings that emerged. A systemic network was generated, presenting the categories of tools such as mathematical (communicative, processes, and concepts) and non-mathematical (physical and written texts). This classification was grounded on data from three central actions of the technicians’ activity, while the constant interrelation and association of these tools during the working process addressed the mathematical practices and supported the construction of mathematical meanings that this group developed from the researchers’ perspective. Technicians’ emerging mathematical meanings referred to place value, spatial, and algebraic relations and were expressed through personal algorithms and metaphorical and metonymic reasoning. Finally, the educational implications of the findings are discussed.  相似文献   
994.
The free vibration and transient wave in a prestressed Rayleigh-Timoshenko beam subject to arbitrary transverse forces are analyzed by the newly developed method of reverberation-ray matrix (MRRM). The effects of shear deformation and rotational inertia are taken into consideration. With a Fourier transform technique, the general wave solutions with two sets of unknown amplitude coefficients are obtained in the transformed domain for an unbonded prestressed beam under the action of arbitrary external excitations. From the coupling at joints and the compatibility of displacements in each member, the free and forced vibration responses of a beam with various boundary conditions are finally evaluated through certain numerical algorithms, Results are presented for a simply-supported beam subject to either a point fixed load or moving load. Good agreement with the finite element method (FEM) is obtained. The present work is instructive for high-speed railway bridge design and structural health monitoring.  相似文献   
995.
This paper reports on the electromagnetic effects on the biological tissue surrounding a transcutaneous transformer for an artificial anal sphincter. The coupling coils and human tissues, including the skin, fat, muscle, liver, and blood, were considered. Specific absorption rate (SAR) and current density were analyzed by a finite-length solenoid model. First, SAR and current density as a function of frequency (10–107 Hz) for an emission current of 1.5 A were calculated under different tissue thickness. Then relations between SAR, current density, and five types of tissues under each frequency were deduced. As a result, both the SAR and current density were below the basic restrictions of the International Commission on Non-Ionizing Radiation Protection (ICNIRP). The results show that the analysis of these data is very important for developing the artificial anal sphincter system.  相似文献   
996.
Early childhood curricula should be authentic and child-centered, however, many teachers still rely on direct instruction lessons. To better define how an integrated curriculum meets the needs of students, this study examined teacher talk and actions during instructional activities with first and second graders under two conditions: (1) subject-integrated social studies lessons of an integrated curriculum unit (experimental condition); and (2) single subject-focused mathematics lessons of a traditional separate subject curriculum (control condition). The mixed-methods study sought to define and compare characteristics of both curriculum approaches. Fourteen hours of observations were collected in each setting. In the integrated curriculum setting, the teacher was a facilitator of teamwork, offering choices, and giving praise; students made choices, decisions, and worked collaboratively. In the traditional setting, the teacher delivered direct instruction and controlled behavior; students followed directions, recalled knowledge, and worked individually. Less teacher energy was expended for behavior management in the integrated curriculum setting, indicating intrinsic motivation of students. Implementation of integrated curricula is recommended because of the student-centered focus that results in greater motivation, ownership, and teamwork, along with deeper knowledge connections. Because many factors hinder implementation, teachers need support when first teaching with this approach.  相似文献   
997.
The process of development occurs according to the pattern established by the genetic potential and also by the influence of environmental factors. The aim of the present study was to focus on the main environmental factors affecting motor development. The review of the literature revealed that family features, such as socioeconomic status, mother’s educational level, and the existence of siblings can affect children’s motor competence. Preschool centers have also become important for children’s development, due to the large amount of time children spend at them nowadays. Moreover, the social cultural context in which a child is reared forms certain demands for his/her motor behavior, favoring specific aspects of motor development and impairing others. A very influential factor (and consequently a very significant educational means) is the use of intervention movement programs. A developmentally adequate movement program can enhance motor development, thus preventing the long term negative consequences that an unfavorable influence of several genetic or the aforementioned environmental factors may have.  相似文献   
998.
999.
According to established theories of attention (e.g., Mackintosh, 1975; Sutherland & Mackintosh, 1971), simple discriminations of the form AX+ BX- result in an increase in attention to stimuli A and B, which are relevant to the outcome that follows them, at the expense of X, which is irrelevant. Experiments that have apparently shown such changes in attention have failed to determine whether attention is enhanced to both A and B, which signal reinforcement and nonreinforcement, respectively, or just to A. In Experiments 1 and 2, pigeons were trained with a number of discriminations of the kind AX+ BX-, before compounds that had been consistently nonreinforced were involved in a subsequent discrimination. Both experiments provided support for theories that propose that more attention is paid to stimuli that consistently signal nonreinforcement than to irrelevant stimuli in simple discriminations.  相似文献   
1000.
There is a large body of research that has explored students’ misconceptions about science phenomena. Less research, however, has been devoted to identifying teachers’ misconceptions, but the results of the few existing studies demonstrate that teachers and students possess similar misconceptions. This study explored the physical science conceptions of 103 elementary science teachers to determine whether, after three decades of misconception research, teachers still possess conceptions similar to those held by students. We found that our teachers expressed misconceptions regarding gravity, magnetism, gases, and temperature that were similar to common student misconceptions. Suggestions for improving science professional development programs are discussed.  相似文献   
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