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41.
The effects of query structures and query expansion (QE) on retrieval performance were tested with a best match retrieval system (InQuery1). Query structure means the use of operators to express the relations between search keys. Six different structures were tested, representing strong structures (e.g., queries with facets or concepts identified) and weak structures (no concepts identified, a query is a bag of search keys). QE was based on concepts, which were first selected from a searching thesaurus, and then expanded by semantic relationships given in the thesaurus. The expansion levels were (a) no expansion, (b) a synonym expansion, (c) a narrower concept expansion, (d) an associative concept expansion, and (e) a cumulative expansion of all other expansions. With weak structures and Boolean structured queries, QE was not very effective. The best performance was achieved with a combination of a facet structure, where search keys within a facet were treated as instances of one search key (the SYN operator), and the largest expansion. 相似文献
42.
The purpose of the study was to examine whether students’ linguistic skills and task-avoidant behavior (i.e., the child-related factors) and the mean level of academic skills (reading comprehension and math) of classmates (i.e., the class-related factor) are associated with teacher judgments of children’s reading comprehension and math skills. The participants were third-grade Estonian-speaking students (n?=?656; age 9?11 years) and their classroom teachers (n?=?51). The results of the structural equation modeling path analyses indicated that teachers tend to judge students showing higher academic and linguistic skills and lower avoidance behavior as higher on the reading comprehension and math skills. In contrast, the classmates’ higher academic skill level was related to lower judgments of individual children’s reading comprehension and math skills by teachers. 相似文献
43.
This study examines the relationships between the environmental attitudes and environmental knowledge of schoolchildren within the framework of an environmental intervention. We employed questions from the 2-MEV model to monitor students’ environmental attitudes in terms of the model factors Preservation and Utilisation while concurrently monitoring three environmental knowledge dimensions (system, action-related and effectiveness knowledge) at three different test times during the course of a four-day field centre programme for fourth-graders (N = 133, Mage = 9.8 years). Probably due to measurement constraints (e.g. a ceiling effect, social desirability), we found no correlation between environmental knowledge and the attitude Preservation at all test times. The attitude Utilisation correlated negatively with all environmental knowledge dimensions, indicating that students who score higher on Utilisation are more likely, for example, to have and gain more system knowledge through programme participation than the other students or vice versa, as a causal relationship cannot be derived from our analyses: system knowledge may also influence Utilisation. In other words, children who refrain from (ab)using nature also seem to put more effort into improving their environmental knowledge and/or children who engage in learning about the environment will become less exploitative towards the environment. 相似文献
44.
Anu Liljeström Jorma Enkenberg Sinikka Pöllänen 《Cultural Studies of Science Education》2013,8(1):51-86
This design experiment aimed to answer the question of how to mediate the practices of authentic science inquiries in primary education. An instructional approach based on activity theory was designed and carried out with multi-age students in a small village school. An open-ended learning task was offered to the older students. Their task was to design and implement instruction about the Ice Age to their younger fellows. The objective was collaborative learning among students, the teacher, and outside domain experts. Mobile phones and GPS technologies were applied as the main technological mediators in the learning process. Technology provided an opportunity to expand the learning environment outside the classroom, including the natural environment. Empirically, the goal was to answer the following questions: What kind of learning project emerged? How did the students’ knowledge develop? What kinds of science learning processes, activities, and practices were represented? Multiple and parallel data were collected to achieve this aim. The data analysis revealed that the learning project both challenged the students to develop explanations for the phenomena and generated high quality conceptual and physical models in question. During the learning project, the roles of the community members were shaped, mixed, and integrated. The teacher also repeatedly evaluated and adjusted her behavior. The confidence of the learners in their abilities raised the quality of their learning outcomes. The findings showed that this instructional approach can not only mediate the kind of authentic practices that scientists apply but also make learning more holistic than it has been. Thus, it can be concluded that nature of the task, the tool-integrated collaborative inquiries in the natural environment, and the multiage setting can make learning whole. 相似文献
45.
Wolfgang Wahlster J?rg Baus Christian Kray und Antonio Krüger 《Informatik - Forschung und Entwicklung》2001,16(4):233-241
Zusammenfassung. Die intelligente Ressourcenadaption ist eine der gro?en Herausforderungen für die n?chste Generation mobiler Navigationssysteme.
Da man typischerweise mehrere Fortbewegungsarten oder Verkehrsmittel kombinieren muss, um an einen Zielort zu gelangen, muss
sichergestellt werden, dass mobile, allgegenw?rtige Navigationshilfen dies über eine jeweils situationsangepasste Benutzerschnittstelle
unterstützen. Der notwendige Wechsel zwischen verschiedenen Positionierungstechnologien soll für den Endbenutzer m?glichst
unbemerkt bleiben. Im folgenden wird ein hybrides Personennavigationssystem vorgestellt, das die in bestimmten Fortbewegungssituationen
verfügbaren Positionierungstechnologien und deren Genauigkeit optimal nutzt, um die Pr?sentation der Wegbeschreibung auf verschiedene
Endger?te und Ausgabemodalit?ten sowie die kognitive Ressourcenlage des Benutzers zu adaptieren.
Eingegangen am 28. Februar 2001 / Angenommen am 8. August 2001 相似文献
46.
The aim of this study was to investigate videos as potential triggers of behavior. Therefore, we applied the theories of triggers and media richness to learn about the triggering efficiency of mobile marketing videos on participants’ behavioral intentions. The experiment involved three distinct test groups, each comprising 41 student participants. From the perspective of media richness theory, we observed that the different kinds of videos had quite similar effects in terms of triggering behavioral changes. However, the mechanisms explaining why triggers were present differed for each video. Further, the results reveal that the consumer's position in the information search process was the most significant reason for the triggering of any kind of effect. In addition, the instructionally designed videos were able to exert an affective triggering effect: the more participants liked the video, the more it affected their participation intention and recall scores. This study extends the media richness research by demonstrating that the effects of media richness can vary within technically similar videos, as they form different logical connections among non-verbal visual cues related to a video's storyline. 相似文献
47.
Jani Ursin Helena Aittola Charles Henderson Jussi Välimaa 《Tertiary Education and Management》2013,19(4):327-340
Mergers are common phenomena in higher education institutions. Improving educational quality is typically one of the stated goals of university mergers. Yet, little information exists about how merging institutions approach this goal. This paper presents results from a study of planning documents created prior to four mergers in the Finnish higher education system. These documents show that there was little concrete attention given to the educational issues related to the mergers. Most attention was placed on administrative issues and issues related to research. When educational issues were mentioned, it was almost always in the form of vague goals with few details provided about how the goals were to be reached. We conclude that this lack of attention to the educational aspect of mergers is a significant weakness of the planning process in these mergers. 相似文献
48.
In this paper we describe how progressive download and adaptive streaming can be combined into a simple and efficient streaming framework. Based on the MPEG-4 file format (MP4) we use HTTP for transport and argue that these two components are sufficient for specifying an open streaming architecture. The client selects appropriate chunks from the MP4 file to be transferred based on (1) the header information (i.e. the “moov” box) in the first part of the file and (2) his observation of network throughput. The framework is completely client driven which allows for better server scalability and reduces signalling overhead. We discuss architecture and implementation issues such as complexity, interoperability and scalability and compare to 3GPP PSS Rel-6 adaptive streaming when appropriate. Measurements from a simple MP4/HTTP streaming client are presented showing that appropriate chunks are selected such that increased reliability is achieved. 相似文献
49.
Tertiary Education and Management - In this paper, I shall put forward a model which highlights key issues to be taken into account in an attempt to improve academic excellence by the means of... 相似文献
50.
Pirjo Aunio Jarkko Hautamäki Nina Sajaniemi Johannes E. H. Van Luit 《British Educational Research Journal》2009,35(1):25-46
The aim of this study was to explore the early numeracy of low‐performing young children. The mean age of the children was six years and four months. The 511 participants belonged to three groups: multi‐language children, children with special educational needs and children with average performance. The results showed that there were significant group differences in early numeracy: the children in the reference group had better relational and counting skills than those with a multi‐language background and those with special educational needs. Some differences were found in counting skills between the children with multi‐language background and those with special educational needs. Finally, (special) educational support for low‐performing children is discussed. 相似文献