• Title/Summary/Keyword: right pyramid

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Problems and Improvements of Teaching the concept of Pyramid in Elementary Mathematics Textbook (초등학교 수학교과서 '각뿔' 지도 방식에 대한 분석과 개선 방안)

  • Lee, Dong Hwan
    • School Mathematics
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    • v.15 no.1
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    • pp.1-14
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    • 2013
  • The purpose of this study is to examine the way of teaching the concept of pyramid in the elementary mathematics textbook and try to improve the problem. Although textbook present the general definition of pyramid as including regular pyramid, right pyramid, oblique pyramid, the textbook intentionally deal with right pyramid or regular pyramid. This intention reflect the intuition or familiarity of students. But, according to the analysis, this intention do not realized. The example of pyramid presented in the textbook do not coincide with mathematical definition and intuition of students. If we intend to deal with right pyramid in the textbook, we should treat of regular pyramid and right pyramid whose base is a rectangular in the textbook.

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A contemplation on the extension of the pyramid in the elementary mathematics textbooks published according to the 2009 revised curriculum (2009 개정 교육과정에 따른 초등학교 수학 교과서에서 제시하고 있는 각뿔의 외연에 대한 고찰)

  • Park, Kyo Sik
    • Journal of the Korean School Mathematics Society
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    • v.20 no.1
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    • pp.43-56
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    • 2017
  • In this thesis, the extension of the pyramid is contemplated through the pyramids presented in textbook $\ll$Math 6-1${\gg}$ published according to the 2009 revised curriculum. In textbook $\ll$Math 6-1${\gg}$, the pyramid is defined by presenting rough sketches of typical pyramids in an extensional definition method. This contrasts with the method of defining the pyramid by using such an extensional definition and a connotative definition method that reveals common properties of all pyramids. In textbook $\ll$Math 6-1${\gg}$, right pyramids whose base can not be regarded as regular polygons, and oblique pyramids are hardly presented. Nonetheless, $\ll$Math 6-1 Teacher's Guide Book${\gg}$ says that we have no choice but to handle oblique pyramids. In this thesis, based on these results, the following implications are presented as conclusions. First, there should be enough discussion on the extension of the pyramid in elementary school mathematics, and agreement to the results. In particular, such discussions are highly necessary in revising the curriculum. Second, in the process of realizing the intention of the curriculum in the textbook through the teacher's guidebook, the extension of the pyramid must be consistent. Third, there should be some consensus about the knowledge that elementary teachers should know about the pyramid.

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A Basic Study on Efficient Acrylic Plate Light Transmission Road Machining (효율적인 아크릴판 광전송로 가공에 관한 기초 연구)

  • Han, Su-Won;Hong, Jun-Hee
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.21 no.1
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    • pp.95-101
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    • 2022
  • This paper proposes a method to process the shape of an optical transmission road and attempts to determine the most suitable single processing method for an acrylic plate optical transmission road. In addition, by manufacturing an automatic pattern processing device to generate certain shapes on the acrylic plate at regular intervals, and measuring the illuminance of the patterned acrylic plate optical transmission road, the measured illuminance was confirmed to fall under the KS illuminance values presented in Table 1. In conclusion, when an incident light of approximately 20,000 lx is applied, the transmission illumination is approximately 200 lx, which represents a transmission rate of approximately 1% for incident light and corresponds to the KS illumination criterion F. Additionally, the right-angle triangular pyramid base size (A) processed at a temperature of 350 ℃ for one second was 2 mm, exhibiting the largest transmission illumination of 280 lx. When the transparent acrylic plate was set to a constant size of 1.6 mm at the bottom of the right-angle triangular pyramid, the fastest response occurred at a processing tip temperature of 350 ℃ (0.04 s). On the other hand, it took 10 s to process the size of the bottom of the right-angled triangular pyramid at a temperature of 200 ℃ to 1.6 mm, and it was confirmed that the optical transmission efficiency was significantly reduced because of the burr that occurred at this time.

A case of Dyke-Davidoff-Masson syndrome in Korea (국소적 경련과 편마비를 동반한 Dyke-Davidoff-Masson 증후군 1례)

  • Lee, Jun Hwa;Lee, Zee Ihn;Kim, Ho Kyun;Kwon, Soon Hak
    • Clinical and Experimental Pediatrics
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    • v.49 no.2
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    • pp.208-211
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    • 2006
  • Dyke-Davidoff-Masson Syndrome (DDMS) is a rare condition characterized by asymmetry of cerebral hemispheric growth with atrophy on one side, ipsilateral compensatory osseous hypertrophy, and contralateral hemiparesis. We experienced a 17 month-old male who presented with left focal clonic or tonic-clonic seizures accompanied by left hemiparesis and developmental delay. Brain MRIs demonstrated progressive atrophy of the right cerebral hemisphere with dilatation of the lateral ventricle, expansion of the ipsilateral frontal sinus with calvarial thickening, and elevation of the petrous pyramid and orbital roof. Brain SPECT showed a decreased volume of the right hemisphere with reduced blood flow. We therefore report a case of DDMS with a review of the literature.

Multi-Focus Image Fusion Using Transformation Techniques: A Comparative Analysis

  • Ali Alferaidi
    • International Journal of Computer Science & Network Security
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    • v.23 no.4
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    • pp.39-47
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    • 2023
  • This study compares various transformation techniques for multifocus image fusion. Multi-focus image fusion is a procedure of merging multiple images captured at unalike focus distances to produce a single composite image with improved sharpness and clarity. In this research, the purpose is to compare different popular frequency domain approaches for multi-focus image fusion, such as Discrete Wavelet Transforms (DWT), Stationary Wavelet Transforms (SWT), DCT-based Laplacian Pyramid (DCT-LP), Discrete Cosine Harmonic Wavelet Transform (DC-HWT), and Dual-Tree Complex Wavelet Transform (DT-CWT). The objective is to increase the understanding of these transformation techniques and how they can be utilized in conjunction with one another. The analysis will evaluate the 10 most crucial parameters and highlight the unique features of each method. The results will help determine which transformation technique is the best for multi-focus image fusion applications. Based on the visual and statistical analysis, it is suggested that the DCT-LP is the most appropriate technique, but the results also provide valuable insights into choosing the right approach.

Automatic generation of reliable DEM using DTED level 2 data from high resolution satellite images (고해상도 위성영상과 기존 수치표고모델을 이용하여 신뢰성이 향상된 수치표고모델의 자동 생성)

  • Lee, Tae-Yoon;Jung, Jae-Hoon;Kim, Tae-Jung
    • Spatial Information Research
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    • v.16 no.2
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    • pp.193-206
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    • 2008
  • If stereo images is used for Digital Elevation Model (DEM) generation, a DEM is generally made by matching left image against right image from stereo images. In stereo matching, tie-points are used as initial match candidate points. The number and distribution of tie-points influence the matching result. DEM made from matching result has errors such as holes, peaks, etc. These errors are usually interpolated by neighbored pixel values. In this paper, we propose the DEM generation method combined with automatic tie-points extraction using existing DEM, image pyramid, and interpolating new DEM using existing DEM for more reliable DEM. For test, we used IKONOS, QuickBird, SPOT5 stereo images and a DTED level 2 data. The test results show that the proposed method automatically makes reliable DEMs. For DEM validation, we compared heights of DEM by proposed method with height of existing DTED level 2 data. In comparison result, RMSE was under than 15 m.

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An FPGA-based Parallel Hardware Architecture for Real-time Eye Detection

  • Kim, Dong-Kyun;Jung, Jun-Hee;Nguyen, Thuy Tuong;Kim, Dai-Jin;Kim, Mun-Sang;Kwon, Key-Ho;Jeon, Jae-Wook
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.12 no.2
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    • pp.150-161
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    • 2012
  • Eye detection is widely used in applications, such as face recognition, driver behavior analysis, and human-computer interaction. However, it is difficult to achieve real-time performance with software-based eye detection in an embedded environment. In this paper, we propose a parallel hardware architecture for real-time eye detection. We use the AdaBoost algorithm with modified census transform(MCT) to detect eyes on a face image. We parallelize part of the algorithm to speed up processing. Several downscaled pyramid images of the eye candidate region are generated in parallel using the input face image. We can detect the left and the right eye simultaneously using these downscaled images. The sequential data processing bottleneck caused by repetitive operation is removed by employing a pipelined parallel architecture. The proposed architecture is designed using Verilog HDL and implemented on a Virtex-5 FPGA for prototyping and evaluation. The proposed system can detect eyes within 0.15 ms in a VGA image.

A Hierarchical Stereo Matching Algorithm Using Wavelet Representation (웨이브릿 변환을 이용한 계층적 스테레오 정합)

  • 김영석;이준재;하영호
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.8
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    • pp.74-86
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    • 1994
  • In this paper a hierarchical stereo matching algorithm to obtain the disparity in wavelet transformed domain by using locally adaptive window and weights is proposed. The pyramidal structure obtained by wavelet transform is used to solve the loss of information which the conventional Gaussian or Laplacian pyramid have. The wavelet transformed images are decomposed into the blurred image the horizontal edges the vertical edges and the diagonal edges. The similarity between each wavelet channel of left and right image determines the relative importance of each primitive and make the algorithm perform the area-based and feature-based matching adaptively. The wavelet transform can extract the features that have the dense resolution as well as can avoid the duplication or loss of information. Meanwhile the variable window that needs to obtain precise and stable estimation of correspondense is decided adaptively from the disparities estimated in coarse resolution and LL(low-low) channel of wavelet transformed stereo image. Also a new relaxation algorithm that can reduce the false match without the blurring of the disparity edge is proposed. The experimental results for various images show that the proposed algorithm has good perfpormance even if the images used in experiments have the unfavorable conditions.

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Flow Resistance and Modeling Rule of Fishing Nets -2. Flow Resistance of Bag Nets- (그물어구의 유수저항과 모형수칙 -2. 자루형 그물의 유수저항-)

  • KIM Dae-An
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.2
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    • pp.194-201
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    • 1995
  • In order to make clear the resistance of bag nets, the resistance R of bag nets with wall area S designed in pyramid shape was measured in a circulating water tank with control of flow velocity v and the coefficient k in $R=kSv^2$ was investigated. The coefficient k showed no change In the nets designed in regular pyramid shape when their mouths were attached alternately to the circular and square frames, because their shape in water became a circular cone in the circular frame and equal to the cone with the exception of the vicinity of frame in the square one. On the other hand, a net designed in right pyramid shape and then attached to a rectangular frame showed an elliptic cone with the exception of the vicinity of frame in water, but produced no significant difference in value of k in comparison with that making a circular cone in water. In the nets making a circular cone in water, k was higher in nets with larger d/l, ratio of diameter d to length I of bars, and decreased as the ratio S/S_m$ of S to the area $S_m$ of net mouth was increased or as the attack angle 9 of net to the water flow was decreased. But the value of ks15m was almost constant in the region of S/S_m=1-4$ or $\theta=15-90^{\circ}$ and in creased linearly in S/S_m>4 or in $\theta<15^{\circ}$ However, these variation of k could be summarized by the equation obtained in the previous paper. That is, the coefficient $k(kg\;\cdot\;sec^2/m^4)$ of bag nets was expressed as $$k=160R_e\;^{-01}(\frac{S_n}{S_m})^{1.2}\;(\frac{S_m}{S})^{1.6}$$ for the condition of $R_e<100$ and $$k=100(\frac{S_n}{S_m})^{1.2}\;(\frac{S_m}{S})^{1.6}$$ for $R_e\geq100$, where $S_n$ is their total area projected to the plane perpendicular to the water flow and $R_e$ the Reynolds' number on which the representative size was taken by the value of $\lambda$ defined as $$\lambda={\frac{\pi d^2}{21\;sin\;2\varphi}$$ where If is the angle between two adjacent bars, d the diameter of bars, and 21 the mesh size. Conclusively, it is clarified that the coefficient k obtained in the previous paper agrees with the experimental results for bag nets.

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Development of Nutrition Education Materials for Healthy Aging (노년기의 올바른 영양관리를 위한 영양교육자료 개발)

  • Ahn, Yun;Kim, Kyung-A;Kang, Hyun-Joo;Kim, Kyung-Won
    • Korean Journal of Community Nutrition
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    • v.11 no.6
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    • pp.740-749
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    • 2006
  • The objective of this study was to develop nutrition education materials for older adults, 'nutritional management for healthy aging'. A booklet and four leaflets were developed based on lesson plans. Topics of the lesson plans included eating habit assessment. Korean food guide pyramid, meal planning, eating sensibly and weight management. The titles of the leaflets were 'Eating right for healthy aging', 'Eat calcium-rich foods', 'Enjoy fruits & vegetables' and 'Weight management'. Illustrations and icons appropriate to the texts were designed using illustrator 9.0 and Photoshop 6.0. Booklet (letter size, 5 chapters, 44 pages) and leaflets (B4 size, 6 sections) focused on modifying undesirable eating habits, providing practical tips for desirable behaviors, and behavioral modification such as recording in a food diary, goal setting and increasing self-efficacy. The drafts were pilot-tested by interviews with older adults(n=10), and minor changes were made. The characteristics of revised materials are as follows; i) materials focused on providing desirable eating behaviors for healthy aging, ii) messages were simple and specific, iii) large fonts(13 pt) were used and materials included interesting pictures and illustrations, iv) materials provided tips for balanced diets and recipes fur older adults, v) materials included sections for participation of learners including assessment of nutritional risk factors and obesity, meal planning and games. The revised materials are self-explanatory and can be used by older adults and in nutrition education for older adults.