• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.10
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• pp.4108-4125
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• 2015

This paper presents a scalable coding method for depth images by considering the quality of synthesized images in virtual views. First, we design a new edge detection algorithm that is based on calculating the depth difference between two neighboring pixels within the depth map. By choosing different thresholds, this algorithm generates a scalable bit stream that puts larger depth differences in front, followed by smaller depth differences. A scalable scheme is also designed for coding depth pixels through a layered sampling structure. At the receiver side, the full-resolution depth image is reconstructed from the received bits by solving a partial-differential-equation (PDE). Experimental results show that the proposed method improves the rate-distortion performance of synthesized images at virtual views and achieves better visual quality.

• Imaging Science in Dentistry
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• v.40 no.1
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• pp.39-44
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• 2010

Purpose : We want to identify the appearance of the buccolingual root dilaceration teeth in the panoramic views and specify the characteristics of these teeth. Materials and Methods : One thousand-six patients were examined on the basis of both panoramic and CT image criteria. We diagnosed and excluded certain teeth from the samples; both prosthodontic or pathologic lesion appearing teeth and mesiodistally dilacerated ones. We meticulously discerned buccolingually dilacerated teeth in the CT images and total 48 samples were selected. The degree of severity in dilaceration was standardized by 2 types of criteria. The samples were differentiated into 3 groups and again categorized into six types showing from the panoramic views: irregular view on the root apex area, clear blunt on the root tip, stepping on root tip, double lamina dura or double tip, arrow-target shaped root, bull's eye, normal view. Results : The types of teeth selected from total 48 buccolingual root dilaceration samples were mandibular first and second molar, premolars, canines, and lateral incisors. The direction of dilaceration was an even percentage to each buccal and lingual side for most selected teeth, however, that of both canines and lateral incisors were directed in almost a buccal side. In the panoramic views, the root types of the buccolingually dilacerated teeth were irregular view on the root apex area, clear blunt on the root tip, stepping on root tip and normal types were almost always normal view. The more severity in dilareated degree, the more chances of observation in the panoramic views were clear blunt on the root tip and stepping on root tip. Conclusion : As observed in the shape of stepping on root tip or double lamina dura in the panoramic views, there can be much more probability to diagnose as a buccolingually dilacerated root.

• Journal of Korean Elementary Science Education
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• v.27 no.2
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• pp.117-133
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• 2008

The purpose of this study was to investigate the elementary students' views about lab-based science learning. For the purpose of this study, semi-structured interviews were conducted with thirty sixth grade students in 12 classes from two elementary schools located in Daegu City. The interview contents consisted of three major categories. The first category was related to attitude toward science lab, the second was related to lab-based science learning which had four sub-categories; recognizing lesson object, planning experiment, performing experiment, drawing conclusion in lab-based science learning in which the students had ordinary have views and expectations, and the last category was related to students' difficulties and something need to be improved in lab-based science learning. In-depth interviews were performed individually and the interviews were recorded. From the interviews, we found that students, in first category, do like lab-activities more than lectures or instruction-based activities in textbook. Students, in second category, wanted generally more discussion for their own activities rather than teacher's instruction and they wanted teacher' mediation conflicts within small groups and comments for students' experiment results. In the last, most of students had fears for some dangerous reagents and accidents. Based on the results, the study suggested that teacher need to give their students to autonomous discussion opportunities to design and interpret data through teacher' guided questions in inquiry steps, to produce some intimate atmosphere for active interaction in small groups, and to teach the safety education on some dangerous reagents.

• Journal of the Korean earth science society
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• v.45 no.4
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• pp.392-403
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• 2024

This study investigated the perceptions of elementary school preservice teachers in their 4th year at K-Education University, an elementary school teacher-training institution, on the nature of science (NOS). To examine the differences in elementary school preservice teachers' perceptions of NOS according to their high school career aptitude, we conducted in-depth interviews with two students each in the humanities and social sciences (HS) and natural sciences (NS) based on the subjects that they had taken while attending high school. For this purpose, we used the Views of Nature of Science Form C (VNOS-C) and Views about Scientific Inquiry (VASI) questionnaires, which were reconfigured. The main research results were that the elementary school preservice teachers showed a positivistic perspective on the NOS, validity of scientific knowledge, difference between theory and law, and social and cultural embeddedness of science. However, they had a latest perspective on the tentativeness of scientific knowledge, observation and inference, and the role of imagination and creativity. In particular, there were clear differences in perception between HS and NS teachers in the areas of tentativeness of scientific knowledge and understanding of observation and inference. Based on these research results, educational implications for improving the science education competencies of preservice elementary school teachers were proposed.

• Journal of Information Science Theory and Practice
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• v.5 no.3
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• pp.6-14
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• 2017

Workplace knowledge sharing is a complex process and there are a large number of studies in the area. In this article three theoretical approaches in library and information science are used to discuss knowledge sharing in the workplace. The approaches are information behavior, social capital, and information culture, and they bring important insights that need to be considered from a holistic management point of view when it comes to knowledge sharing. The individual's relation to different levels of context is important, meaning both in relation to work roles, work tasks, situations, organizational structures, and culture. The frameworks also shed light on where and how knowledge sharing activities are present in the organization. From a knowledge management point of view, it is important to acknowledge that when knowledge is valued, there is also an awareness of the knowledge sharing activities. Also, in addition to more traditional views of context, the frameworks bring forward different views on context, such as time and space as contextual factors.

• Journal of The Korean Association For Science Education
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• v.33 no.3
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• pp.553-568
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• 2013

Although many researchers and science educators agree that understanding of the nature of science is essential in order for students to be a scientific literate person, it is not easy to compromise exactly what kind of understanding of the nature of science is required to achieve this goal (Smith & Scharmann, 1999). This study discusses a theoretical background about the nature of science (NOS) including some consensus views of the NOS that several important U.S. educational reform documents and science researchers have presented over the past several decades. Finally, this study proposes an inclusive framework of the nature of science based on the four categories of scientific literacy, which are (1) science as a body of knowledge, (2) science as a way of investigating, (3) science as a way of thinking, and (4) the interaction of science, technology, and society. Each category of the framework includes several statements about the nature of science to describe each theme of the NOS. This framework is comprehensive and inclusive because it is suggested by examining several major U.S. national-level documents and in the publications of science education researchers presented about the nature of science. Significantly, many of the key ideas were added into category (4) and category (3), which indicates that the current literature stresses the relationship among science, technology, and society as well as the work of scientists.

• Journal of The Korean Association For Science Education
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• v.12 no.1
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• pp.1-9
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• 1992

This study investigated 15 Postgraduate students' conception toward the nature of science and the changes of those conceptions through the course called 'Philosophy of Science and Science Education', And another 8 postgrauate students who took the course called 'Mathematical Physics' were also investigated for comparison. A survey questionnaire involving 9 items was developed and administered before and after the course to both groups. Individual interviews with students taking 'Philosophy of Science and Science Education' were carried out in a small scale for obtaining additional information about their background knowledge. The results of this study showed that the students' traditional views of philosophy of science including the objective observation and the inductive method were reduced after the course, 'Philosophy of Science and Science Education'. On the other hand. views of modem philosophy of science including the theory-laden observation, the tentativeness of scientific knowledge and science as human activities became more popular. It was also found that their conceptions towards Science were different according to their previous knowledges on the philosophy of science and their majors.

• Journal of the Korean Society of Earth Science Education
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• v.10 no.2
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• pp.199-213
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• 2017

The purpose of this study was to find out what pre-service teachers' views of as a good science class in evaluating class demonstrations. The study was conducted on 32 students in the second year of college who are attending teacher training schools located in central region, Korea. 32 pre-service teachers demonstrated the class with a group of 2 students, and a total of 16 lessons were demonstrated. They also evaluated the class by participating in 15 lessons except ones own class. Therefore all the collected evaluation papers were 480 sheets. This study analyze this evaluation paper and find out the good science class that earth science pre-service teachers think. As a result, the pre-service teachers' views of good science class analyzed by 3 categories. The three categories were 'Highly Engaged Instruction', 'Well-structured class design', and 'Qualitatively superior class materials'. In other words, the pre-service teachers' views that well-structured class design and active interaction were the requirements of good science class. This study confirmed that pre-service teachers can draw images of good science class through experience of class demonstration and class evaluation.

• Journal of the Korean Chemical Society
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• v.48 no.3
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• pp.291-299
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• 2004

The purpose of this study is to investigate views of high school students' learning of chemistry as one aspect of conceptual ecology. The results of this study will help us expand our understanding of conceptual change as it is used to evaluate learners. I made use of an interpretative research design based on principles of naturalistic inquiry. The participants in this study were six sophomore students. The picture of a chemistry class we draw from analyzing data is a play on stage with little interaction. Students accept passive and difficult-to-modify views of the learner roles that they should play in the chemistry classroom. Students identified chemistry classes as conservative places. 'Transmission' seems to remain the persistent and dominant classroom cultural dynamic for both the teaching and learning of chemistry. Students should understand about learning processes, and how to play, monitor, evaluate and regulate them. Students should experience the plausibility and fruitfulness of learning chemistry, and it will help students to feel a "love of learning chemistry." As students change their views of learning chemistry, it will help to improve their learning and to experience conceptual change in chemistry learning.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2615-2619
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• 2013

Background: The aim of this study was to examine the effects of perceived parental attitudes on children's discernment of cigarettes. Materials and Methods: The study sample consisted of 250 children attending grades 6, 7 and 8. Data were collected via a socio-demographic survey questionnaire, the Parental Attitude Scale (PAS) and the Decisional Balance Scale (DBS). Data analysis covered percentages, medians, one-way analysis of variance (ANOVA) and post-hoc tests using a statistical package. Results: There were 250 participants; 117 were male, 133 were female. The mean age was $13.1{\pm}0.98$ for the females and $13.3{\pm}0.88$ for the males. A statistically significant difference was found in the children's mean scores for 'pros' subscale on the Decisional Balance Scale (DBS) according to perceived parental attitudes (F=3.172, p=0.025). There were no statistically significant differences in the DBS 'cons' subscale scores by perceived parental attitudes. Conclusions: It was determined that while perceived parental attitudes affect children's views on advantages of smoking, they have no effect on children's views on its disadvantages.