• Asia pacific journal of information systems
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• v.14 no.3
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• pp.169-187
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• 2004

Self-maintainability of data warehouse(DW) views is an ability to maintain the DW views without requiring an access to (i) any underlying databases or (ii) any information beyond the DW views and the delta of the databases. With our proposed method, DW views can be updated by using only the old views and the differential files such as different files, referential integrity differential files, linked differential files, and backward-linked differential files that keep the truly relevant tuples in the delta. This method avoids accessing the underlying databases in that the method achieves self-maintainability even in preparing auxiliary information. We showed that out method can be applicable to the DW views that contain joins over relations in a star schema, a snowflake schema, or a galaxy schema.

• Asia pacific journal of information systems
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• v.5 no.2
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• pp.131-142
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• 1995

In distributed database systems materialized views are useful to solve many problems caused by data replication. This paper deals with the problem of updating materialized views incluing join operations. We use a differential update which uses logs that record the change of base tables in certain periods. This method avoids locking of the base tables so that it makes the system more efficient. We update materialized views periodically to save the updating cost envolved. A screen test is applied to differential files to eliminate tuples that are irrelevant to any of the views being updated. Using these methods, a detailed procedure is addressed to refresh materialized views. Then we show that our update procedure performs better than a semijoin approach.

• Journal of The Korean Association For Science Education
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• v.24 no.1
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• pp.121-128
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• 2004

This study was to investigate high students' conceptions of acids and bases, and their views on learning science. Multiple sources of data were collected over six months with a participation of sit tenth graders and their science teacher. The transcripts of interviews and other data were examined with an eye toward students' conceptions of acids and bases, and their views of learning science. Students' views of science are displayed the representative pattern. Each pattern is represented with an episode. Students' views of learning have been found to reflect the transmissive models of science educational practice. Students accept passive and difficult-to-modify views of the learner roles that they should play in the science classroom. Students identified science classes as conservative places, despite the introduction of science literacy as a goal of Korean science education since 1980. Behaviorism remains the major influence in their expectation, design, and practice in school science. Moreover, 'transmission' remains the persistent and dominant classroom cultural dynamic for both teaching and learning of science.

• Journal of The Korean Association For Science Education
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• v.41 no.2
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• pp.83-92
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• 2021

The purpose of this study is to investigate elementary school students' understandings about scientific inquiry. Data were collected from 119 elementary students who are in the 4^th grade using the Views About Scientific Inquiry questionnaire for elementary students (VASI-E). We also conducted semi-structured interviews of 21 students from 119 students who responded to VASI-E. Students' responses were analyzed as naive, mixed, or informed views on each aspect of scientific inquiry that VASI-E includes. We found that, first, 53.8% of students have mixed views, and 30.3% of students have informed views, and 16% of students have naive views on the knowledge 'investigation begin with a question'. Second, 54.6% of students have naive views, 37.8% of students have mixed views, and 7.6% of students have informed views on the knowledge 'scientists use many methods to answer their questions.' Third, 47.9% of students have informed views, 34.5% of students have naive views, and 17.6% of students have mixed views on 'procedures guided by question asked.' Fourth, 55.5% of students have mixed views, 42% of students have informed views, and only 2.5% of students have naive views on 'conclusions must be consistent with data and explanations come from data and prior knowledge.' Based on the results, implications for teaching and learning scientific inquiry at elementary level in Korea were discussed.

• Journal of Korean Elementary Science Education
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• v.30 no.4
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• pp.430-441
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• 2011

We investigated the elementary students' epistemological views on the nature of scientific measurement. The Views About Scientific Measurement (Ibrahim, 2005) was administered to 117 sixth graders. The analyses of the results indicated that there was an inconsistency in their epistemological views depending on the contexts of the measurement. They also had some difficulties in understanding a distribution of the data, which is needed to understand the necessity of repeating measurements, choosing a best representative value, and comparing data sets. They were found to have some naive views on scientific measurement which influenced negatively for fostering modern epistemological views on the nature of scientific measurement. The results suggest that the nature of scientific measurement should be emphasized explicitly in the national curriculum, and an effective method which improves elementary students' epistemological views on the nature of scientific measurement also be developed.

• Journal of Korean Elementary Science Education
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• v.29 no.3
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• pp.243-251
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• 2010

The purpose of this study is to investigate the relationships between elementary school teachers' points of view about the organization of the science curriculum and their views on the nature of science (NOS). We surveyed 132 elementary school teachers' view points about these two kinds of views, analyzed the data by their variables, and compared the two viewpoints with their personal details. The elementary school teachers thought the science curriculum should be emphasized through the process more than contents. They thought the contents of the science curriculum should be integrated rather than separated. As teachers' career progressed, they focused on the contents more than the process. On the other hands, because elementary school teachers showed the NOS views as relativism, deductivism, decontextualism, content, and instrumentalism, when we plotted sub-viewpoints of NOS in process-content dimension, we thought it would be similar distributions with point of views on the organization of science curriculum. However, there was no meaningful relation. This showed that teachers' views on the organization of the curriculum and the NOS are totally different. These findings suggest further research is needed to find how factors influence elementary school teachers' views on the organization of the science curriculum and what inclinations can occur in science classes with their different views.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1998.06b
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• pp.147-153
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• 1998

This paper provides a method for video augmentation using image interpolation. In computer graphics or augmented reality, 3D information of a model object is necessary to generate 2D views of the model, which are then inserted into or overlayed on environmental views or real video frames. However, we do not require any three dimensional model but images of the model object at some locations to render views according to the motion of video camera which is calculated by an SFM algorithm using point matches under weak-perspective (scaled-orthographic) projection model. Thus, a linear view interpolation algorithm is applied rather than a 3D ray-tracing method to get a view of the model at different viewpoints from model views. In order to get novel views in a way that agrees with the camera motion the camera coordinate system is embedded into model coordinate system at initialization time on the basis of 3D information recovered from video images and model views, respectively. During the sequence, motion parameters from video frames are used to compute interpolation parameters, and rendered model views are overlayed on corresponding video frames. Experimental results for real video frames and model views are given. Finally, discussion on the limitations of the method and subjects for future research are provided.

• Journal of KIISE:Computing Practices and Letters
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• v.10 no.1
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• pp.14-24
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• 2004

Views are essential in providing logical data independence for database systems. Object views in object-oriented/object-relational databases have requirements quite different from those of relational databases due to support for object-oriented concepts. Although many commercial object-oriented/object-relational database systems support object views, implementation techniques have not been discussed sufficiently in the literature. In this paper, we devise a technique for implementing views in object-oriented/object-relational databases and apply it to the ODYSSEUS object-relational database system. We first analyze the requirements of object views. Next, to implement object views, we extend the existing query modification algorithm that has been proposed for implementing views in relational databases. Next, we compare the features of the proposed object view with those of object views in commercial object-relational database systems. It is shown that the proposed object view supports all object-oriented concepts such as object identifiers, inheritance, methods, and composite objects, while existing object views support part of them. Last, we propose detailed techniques for implementing the extended query modification algorithm in the ODYSSEUS object-relational database system.

• ETRI Journal
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• v.38 no.4
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• pp.767-775
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• 2016

Automatic container code recognition from a captured image is used for tracking and monitoring containers, but often fails when the code is not captured clearly. In this paper, we increase the accuracy of container code recognition using multiple views. A character-level integration method combines recognized codes from different single views to generate a new code. A decision-level integration selects the most probable results from the codes from single views and the new integrated code. The experiment confirmed that the proposed integration works successfully. The recognition from single views achieved an accuracy of around 70% for the test images collected on a working pier, whereas the proposed integration method showed an accuracy of 96%.

• Research in Mathematical Education
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• v.6 no.1
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• pp.1-28
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• 2002

This study explored teachers (n = 219) from northern, central, southern and eastern Taiwan concerning their views about children's learning difficulties, mathematical instruction and school mathematics curricular. Results showed that teachers' mathematics knowledge or their instruction methods had no significant influence on their views of children's learning difficulties. Even though teachers indicated that understanding of abstract mathematical concepts was the most prominent difficulty for children, they tended to employ direct instruction rather than constructive and cooperative problem solving in their teaching. However, teachers' views of children's learning difficulties did influence their instructional practice. Results from in-dept interviews revealed that there were some obstacles that prevented teachers from putting constructiveism perspectives of instruction into teaching practice. Further investigation is needed to develop a better understanding of epistemology and teaming psychology as well as to help teachers create constructive learning situations.