• 제목/요약/키워드: similar figures

검색결과 162건 처리시간 0.029초

수학과 교육과정에 비추어 본 탱그램과 유사탱그램의 재조명 (Revisiting Tangram and Similar Tangrams based on Mathematics Curriculums)

  • 송상헌
    • 대한수학교육학회지:수학교육학연구
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    • 제18권3호
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    • pp.391-405
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    • 2008
  • 탱그램이라고 불리는 전통적인 칠교판(도형판)에 대한 기존의 연구들도 학교수학의 내용을 바탕으로 한 활동의 가능성에 초점을 두고 있다. 현행 수학과 교육과정에서 탱그램을 언급하고 있기는 하지만 교과서의 활용에서 탱그램의 유용한 특성을 제대로 반영하지 못할 뿐만 아니라 교육과정상의 다른 내용과 제대로 연결을 시키지 못하고 있다. 이에 본 연구는 초등학교 수학 교과서와 익힘책에 제시하고 있는 탱그램 사용이 교육과정과의 관련에서 갖는 문제점과 한계를 분석하면서, 학교 현장에서 바르게 활용할 수 있는 방안(제대로 그리기, 모양이 아닌 다각형 만들기, 수학적사고와 관련하여 현 교육과정의 수준에 적합한 활동분석, 교육과정의 한계를 넘나들며 활용할 수 있는 수준별 도형 탐구의 예시 등)과 유사탱그램까지 좀 더 확장하여 보다 적극적으로 활용할 수 있는 대안을 제안하였다.

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A New Record of Collix stellata (Lepidoptera: Geometridae) from Korea

  • Choi, Sei-Woong;Na, Sang-Hyun
    • Animal Systematics, Evolution and Diversity
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    • 제27권2호
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    • pp.164-166
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    • 2011
  • We report a larentiine species, Collix stellata Warren, for the first time from Korea. Two males and one female were collected from Jeju-do Island, South Korea. Collix stellata is similar to Collix ghosa Walker in external appearances, but can be distinguished by the relatively larger discal dot on forewing and the relatively slender valva with distally projected margin of male genitalia. Diagnosis and description of the species are given with the figures of the genitalia.

PZT 순수박막과 PZT/PT 교차박막의 적외선 감지 특성 비교 (Pyroelectric Peyformance Evaluation of Pure PZT and Alternately Deposited PZT/PT Thin Films)

  • 고종수;곽병만
    • 대한기계학회논문집A
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    • 제26권6호
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    • pp.1001-1007
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    • 2002
  • To improve the performance of the PZT thin flms, each PZT and PT layer was alternately deposited on a Pt/Ti/Si$_3$N$_4$/SiO$_2$/Si substrate by a modified sol-gel solid precursor technique. For comparison, PZT thin films were also prepared with an identical method under the same conditions. XRD measurement revealed that the diffraction pattern of the multilayer film was due to the superimposition of the PZT and PT patterns. At 1㎑, a dielectric constant of 389 and 558, a dielectric loss of 1.2% and 1.1% were obtained for the PZT/PT and PZT thin films, respectively. If we consider the PT dielectric constant to be 260, it is clear that the dielectric constant of alternately deposited PZT/PT thin films was well adjusted. The PZT/PT thin film showed a low dielectric constant and a similar dielectric loss compared with those of the PZT film. The figures of merit on detectivity for the PZT/PT and PZT thin films were 20.3$\times$10$\^$-6/㎩$\^$-$\sfrac{1}{2}$/, and 18.7$\times$10$\^$-6/㎩$\^$-$\sfrac{1}{2}$/, and the figures of merit on voltage response were 0.038㎡/C and 0.028 ㎡/C, respectively. The high figures of merit for the PZT/PT film were ascribed to its relatively low dielectric constant when compared to the PZT thin films.

프랙털 조형 활동이 유아의 수학적 능력에 미치는 영향 (The influence of fractal plastic activity for early childhood's mathematics capacity about space and figure)

  • 계영희;하연희
    • 한국수학교육학회지시리즈E:수학교육논문집
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    • 제30권4호
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    • pp.453-468
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    • 2016
  • 본 연구자는 만다라를 유아미술교육에 활용하였을 때 유아의 공간과 도형의 개념이 현저하게 향상된 결과를 얻었다. 본 논문은 그 후속연구로 부산광역시 H어린이집의 만3세 유아 44명, 만5세 유아 34명을 대상으로, 만다라와 유사한 구조를 가지는 프랙털 조형 활동이 유아의 공간과 도형의 수학적 개념에 미치는 영향을 연구하였다. 연구결과 만3세 유아는 4개 영역에서, 만5세 유아는 3개 영역에서 유의미함을 보였다. 만3세 유아는 조형 활동에서 과거의 기억을 표현하기 시작했으며, 만5세 유아는 스토리를 만들며 실물과 유사하게 재현하기도 했다. 또한 만5세의 경우 그림과 지점토의 표현에서 성별의 차이가 뚜렷하게 드러났으며, 만다라보다 프랙털이 더욱 효과적임을 보였다.

액상소결한 탄화규소의 집합조직 발달에 관한 연구 (A Study on Texture Development in Liquid-Phase Sintered Silicon Carbide)

  • 성한규;조경식;박노진;최헌진;이준근
    • 한국세라믹학회지
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    • 제37권4호
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    • pp.320-326
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    • 2000
  • Development of texture in SiC materials by hot-pressing and subsequent annealing was studied. Crystallographic texture type was characterized by measuring X-ray pole figures on the perpendicular plane to the hot-pressing direction. Observed all pole figures were nearly axially symmetric (fiber texture). In case of ${\beta}$-SiC materials, the pole density of basal plane (0004) increased as annealing time increased, in contrast, other planes (hkil) of ${\beta}$-SiC materials and all planes of ${\alpha}$-SiC materials nearly remained unchanged. In the case of ${\beta}$-SiC materials, therefore, a weak texture of (0001) plane at the normal direction took place in the 8h annealed samples, resulting from grian growth. The fracture toughness values of ${\alpha}$-SiC materials measured in both planes parallel and perpendicular to the hot-pressing direction were very similar. However, the fracture toughness of ${\beta}$-SiC materials measured parallel to the hot-pressing direction were higher than that measured perpendicular to the hot-pressing derection, relatively, because of the texture and the microstructure anisotropy.

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중국의 모란문양 연구 (A Study of Chinese Peony Pattern)

  • 김재임;박춘순
    • 복식
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    • 제44권
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    • pp.57-75
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    • 1999
  • The purpose of this study is to infer the shape and change as auspicious symbolic meaning and figures of a peony pattern. For this study. I analyzed the example of a peony pattern, which is traditional Chinese pattern appeared on a ceramic and textile. The results of this study are as following. First, a peony has particular title, such as 'the king of flowers' and 'the most beautiful woman in country and the smell in heaven' originated in a verse of a poet at Dang's Dynasty. It is reputed to be the best of all flowers, representing beauty, and a beauty. Second, the basic meaning of a peony pattern used as auspicious pattern is prosperity and it has various meanings of it's similar kind through several auspicious objects and combination. Also, it was used for the purpose of adequating the desire of man's blessing mentality. Third, four kinds of characteristics of a peony pattern are as following. 1) A peony pattern has similar shape with 'Bosanghwamoon', which was used as a pattern at formerly period of peony flowers. It was used as realistic shape gave vividness to the characteristic of peony on the shape of 'Bosanghwamoon'. 2) 8-petaled, unique leaves and veins were described in detail by vivid sketching shape of real peony flower. 3) Laying stress on the characteristics of peony flower, which is large and magnificent, several folds petals were described abundantly by exaggerated shape or a shape of big honeycomb. And unique leaves were described realistically on these. 4) It was also expressed peculiar characteristic of peony flower composed of several pieces by weakened design shape.

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한국여성과 일본거주 한인여성의 신체 계측치 비교연구 (The Research of Difference of Body Measurements between Korean Women Residing in Korea and Korean Women Residing in Japan)

  • 이종숙;임순
    • 한국의상디자인학회지
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    • 제9권2호
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    • pp.93-101
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    • 2007
  • The purpose of the study was to offer basic documents to the textile fashion industry by investigating changes of figures followed by various factors as each other social and cultural environment regardless of the same race. The study conducted a questionnaire survey of Korean women and Korean women in Japan to twenties, forties and sixties. The study enforced measurement from February, 2006 to March, 2006 and from July, 2006 to August, 2006 with R. Martin's Measurement Method of Anthropometry in total 49 measurement items. Also, the study treated statistics of the documents with SPSS WIN 10.0 program. As the result which studied comparison of figures with basic statistics, t-test and more, the study got the following conclusion. Most of Korean women and Korean women residing in Japan have big individual differences in obesity, especially width, thickness, and girth of waist showed the largest variation proving considerable individual difference in waist. In a body measurement comparison, twenties, forties, and sixties of Korean women residing in Japan are higher in heights compare to Korean women, while Korean women have wider and thicker waists than Korean women residing in Japan. In a body difference comparison, categories that showed significant differences are 40's>20's>60's in order and twenties and sixties showed only small difference. In conclusion, Korean women have longer, wider, thicker and smaller waist than Korean woman residing in Japan. When divided by age groups, forties and sixties Korean women are longer in waist, shorter in heights, fatter in weights. Twenties have long waist similar to forties and sixties, but had no significant difference in heights and weights.

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대추나무 미친병에 관한 연구(II) -엽 유관속구조에 미치는 해부학적 영향에 대해서-

  • 홍순우
    • Journal of Plant Biology
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    • 제3권2호
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    • pp.29-34
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    • 1960
  • From the view point of phytopathological anatomy, the author has tried to study the effect of the shoot cluster disease virus on the internal structure of vascular tissues of chinese date tree (Ziziphus jujuba var. inermis Rehd.) comparing healthy checks and diseased plants. The materials were collected at the several sites, Kumgock-Ri, Masuc-Ri, Kyungi-Do, and near the campus of Korea University and around the area of Chongam-Dong, Seoul City, from August 15th to September 5th 1959. The leaf materials of healthy and diseased plants are fixed and aspirated in two kinds of killing solutions, formalin-acetic acid alcohol solution and Craf III solution. Sections were cut at 5-10$\mu$ thickness and stained with the double staining reagents of safranin and fast green. In this experiment the author has observed that there are marked structural changes in the infected plants in contrast of healthy checks. As figures 3-7 show that the following characteric changes have taken place on infected plants: 1) the arrangement of irregularly developed sieve elements in phloem, 2) the degeneration of phloem elements, 3) the irregular arrangement of epidermis in mid-vein, 4) more necrosis is observed among the parenchymatous cells, 5) abundant accumulatin of starch grains in parenchymatous cells, . In contrast to the above irregularities caused by the virus disease, the healthy checks appear normal structures as shown in figures 1 and 2. In adding to the all features noted above, the author could also observe an interesting feature that the xylem elements in mid-vein vascular bundle tissues are considerably disorganized to show the unspecialized vessel elements, the irregularly arranged xylem elements. However, this kind of irregularities which occur in xylem under the virus infection has not been reported previously. The features noted on the internal structure of vascular bundle under the condition of infection by the shoot cluster disease on chinese date trees appear to be more or less closely similar to the symptoms of the bunchy-top of banana and the yellow dwarf disease of barley in respect to the fact that whether phloem necrosis takes place as a primary symptom or a secondary symptom. In all these disease, primary histological changes of hypoplasia and hypertrophy are preceeded by the necrosis of phloem.

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A Taxonomic Study on the Burrowing Cricket Genus Velarifictorus with Morphologically Resembled Genus Lepidogryllus (Orthoptera: Gryllidae: Gryllinae) in Korea

  • Kim, Tae-Woo
    • Animal Systematics, Evolution and Diversity
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    • 제29권4호
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    • pp.294-307
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    • 2013
  • The burrowing-cricket genus Velarifictorus Randell, 1964 is reviewed in Korea, comparing with morphologically resembled genus Lepidogryllus Otte and Alexander, 1983 for the first time. First, Velarifictorus aspersus borealis Gorochov, 1985 is confirmed from only restricted area of southern regions in Gyeongsangnam-do and Jeollanam-do. Second, Velarifictorus micado (Saussure, 1877) is confirmed from nearly all around the Korean peninsula including North Korea. Third, the previously not recorded Velarifictorus ornatus (Shiraki, 1911) is newly recognized from South Korea. Relating to the genus Velarifictorus, the resembled genus Lepidogryllus Otte and Alexander, 1983 and its species Lepidogryllus siamensis (Chopard, 1961) com. & stat. nov. is studied and compared with Velarifictorus members. A key, descriptions, tables, photographs, figures, oscillograms and spectrograms of calling sounds are provided to aid identification between the four similar species.

Seminiferous Epithelium Cycle and Developmental Stages of Spermatids in the Clethrionomys rufocanus

  • Lee, Jung-Hun
    • 한국발생생물학회지:발생과생식
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    • 제17권2호
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    • pp.87-97
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    • 2013
  • The seminiferous epithelium cycle and developmental stages of spermatids in Clethrionomys rufocanus were observed under a light microscope. The seminiferous epithelium cycle was divided into 8 stages. Type Ad spermatogonia appeared through all stages. Type Ap, In, and B spermatogonia appeared in stages I, II, III, and IV. In the first meiosis prophase, the leptotene spermatocytes appeared from stage V, the zygotene spermatocytes in stages I, VI, VII, VIII, the pachytene spermatocytes from stages II to VI, the diplotene spermatocytes in stage VII. The meiotic figures and interkinesis spermatocytes were observed in stage VIII. Developing spermatids were subdivided into 10 steps, based on the morphological characteristics such as the acrosome formation changes in spermatozoa, nucleus, cytoplasm, and spermiation changes. The C. rufocanus spermatocytogenesis and spermiogenesis results displayed similar results with Apodemus agrarius coreae and A. speciosus peninsulae. Considering all the results, the spermatogenesis may be useful information to analyze the differentiation of spermatogenic cells and the breeding season.