• Proceedings of the Korean Statistical Society Conference
• /
• 2005.11a
• /
• pp.175-180
• /
• 2005

탐색적자료분석을 위한 도구로서 그래픽 방법들을 자주 쓰게 되는 데 이러한 그래픽 방법 중 평행좌표그림을 대상으로 이 방법을 확장하여 볼 수 있다. 이러한 확장된 그림인 정다각기둥평행좌표그림은 탐색적자료분석 도구로서 유용하게 쓰일 수 있다.

• Journal of Elementary Mathematics Education in Korea
• /
• v.23 no.4
• /
• pp.481-506
• /
• 2019

Perpendicularity and parallelity are important concepts in Mathematics as well as real-life contexts. However, those concepts are rather reduced in 2015 revised curriculum compared to previous 2009 revised curriculum. This study firstly analyzed teaching method related to perpendicularity and parallelity in a series of mathematics textbooks of Korea, Singapore and Japan. Moreover, the unit of perpendicularity and parallel was redesigned in a way to understand the concepts meaningfully and to give opportunities for students to explore how to make perpendicular and parallel lines. The results showed that noticeable changes has been as the curriculum was revised in Korea. Also, three countries showed some differences in concepts definition and learning activities. This study is expected to suggest implications for how to teach perpendicularity and parallelity in elementary school mathematics.

• The Korean Journal of Applied Statistics
• /
• v.9 no.1
• /
• pp.45-52
• /
• 1996

In this paper, we describe the basic properties of the parallel coordinate plots and propose a dynamic parallel coordinate plot. This dynamic parallel coordinate plot can be used as a dynamic graphics tool for multivariate data analysis.

• Journal of the Korean Society of Radiology
• /
• v.6 no.6
• /
• pp.477-481
• /
• 2012

An X-ray diffractometer which has various X-ray optics can give qualitative and quantitative information for a sample using a nondestructive analysis method. A parallel beam optic passes the parallel beam and removes divergent beam generated from an X-ray tube. The parallel beam optic used in the X-ray diffractometer was fabricated by wire cut and grading of stainless steel plates and was evaluated its performance using an X-ray imaging system. The measured parallelization of 6.6 mrad for the fabricated the parallel beam optic was a very close to the expected value of 6 mrad. An X-ray imaging technique for evaluating the parallel beam optics can estimate parallelization for each plate and can be used to other X-ray optics.

• Proceedings of the Korean Statistical Society Conference
• /
• 2003.10a
• /
• pp.167-172
• /
• 2003

혼합물실험에서 성분의 개수가 많고 성분에 대하여 제한조건이 있는 경우 흥미영역을 도시하는 작업은 성분의 개수가 4개 이상일 때 힘든 작업이 된다. 또한 반응변수가 여러 개인 경우 최적화문제도 까다롭게 된다. 이때, 탐색적 자료분석의 한 도구로서 평행좌표그림을 이용하면 통계자료분석시 많은 도움을 받을 수 있다.

• Journal of the Korea Computer Graphics Society
• /
• v.6 no.4
• /
• pp.29-34
• /
• 2000

This paper classifies the structure of the intersection curve between a surface of extrusion and a free-form surface. Our algorithm computes the silhouette curve of the free-form surface with respect to the unique ruling direction of the surface of extrusion. By intersecting the silhouette curve and the base curve of the surface of extrusion, we can classify the topological structure of the intersection curve, and compute all singularities in the intersection curve. Moreover, we can determine which ruling lines of the surface of extrusion intersect the other free-form surface and how many times. This classification provides a robust and efficient method for computing the intersection curve.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.4 no.4
• /
• pp.1-7
• /
• 2001

Remotely sensed data is the most fundamental data in acquiring the GIS informations, and may be analyzed to extract useful thematic information. Multi-spectral classification is one of the most often used methods of information extraction. The actual multi-spectral classification may be performed using either supervised or unsupervised approaches. This paper analyze the effect of assigning clever initial values to image classes on the performance of parallelepiped classification algorithm, which is one of the supervised classification algorithms. First, we investigate the effect on serial computing model, then expand it on MIMD(Multiple Instruction Multiple Data) parallel computing model. On serial computing model, the performance of the parallel pipe algorithm improved 2.4 times at most and, on MIMD parallel computing model the performance improved about 2.5 times as clever initial values are assigned to image class. Through computer simulation we find that initial values of image class greatly affect the performance of parallelepiped classification algorithms, and it can be improved greatly when classes on both serial computing model and MIMD parallel computation model.

• Korean Journal of Optics and Photonics
• /
• v.19 no.4
• /
• pp.276-286
• /
• 2008

The representative alignments for taking a stereo image by using a stereoscopic camera are the toed-in and the parallel alignment. In this paper, we tried to find important factors in the process that captures the stereo image by modifying parallel type 3D camera alignment to take the same object information as, for instance, when toed-in type was used. The modified parallel type 3D camera has merits in both types. As a result, three important factors are found by simulation to be inter-camera distance, field of view and convergence angle for both types. And the change of the convergence angle is known to be the most important factor at the stereo fusible area in processing. The effective ranges of these factors to simulate perfectly toed-in type by modified parallel type are strongly dependent on a user's circumstances such as mobile, official, theater and so on. Additionally, the error of the simulation is reduced when the focal length of the stereo camera is short and the convergence angle becomes smaller.

• Journal of Educational Research in Mathematics
• /
• v.13 no.4
• /
• pp.485-493
• /
• 2003

The purpose of this study is to suggest the alternative strategies for teaching mensuration of parallelogram raised by Max Wertheimer, a gestalt psychologist who was particularly concerned with mathematics learning and teaching. For this, 77 student teachers were paper and pencil tested and we could get the 7 interesting and useful ideas from their datas in spite of the fact that not many student teachers correctly responsed. Analysing the datas, it turned out all the 7 ideas are related to equivalent transformation and can make children more easily to see the structure of area of Wertheimer's parallelogram than traditional approach.

• Communications of Mathematical Education
• /
• v.27 no.1
• /
• pp.81-97
• /
• 2013

In this study, we investigated how the relationship between 'parallel' lines and 'identical' lines is stated in mathematics textbooks of the 2007 revised national curriculum. In school mathematics, 'parallel' lines and 'identical' lines are explicitly distinguished in the perspective of 'coincidence', whereas 'identical' lines are implicitly regarded as a special case of 'parallel' in the perspective of 'slope'. These different treatments could bring out a confusion as was in the mock mathematics test for 2012 College Scholastic Ability Test. To resolve this confusion, it needs to be considered that the relationship between 'parallel' lines and 'identical' lines are more clearly stated in the context of 'slope' such as in some textbooks for the 4th and 5th curriculum and a textbook of Japan.