• 제목/요약/키워드: Phases and patterns

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초등학교 5학년 학생들의 수학적 논증을 강조한 수업의 실제 (Teaching Practices Emphasizing Mathematical Argument for Fifth Graders)

  • 황지남
    • 한국수학교육학회지시리즈C:초등수학교육
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    • 제26권4호
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    • pp.257-275
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    • 2023
  • 본 연구는 초등학교 5학년 학생들을 대상으로 수학적 논증을 강조한 수업을 설계 및 구현하여 수업의 실제를 분석하였다. 문헌 연구를 통해 수학적 논증을 강조한 수업을 1) 패턴 주목하기, 2) 추측 분명히 나타내기, 3) 시각적 모델로 표현하기, 4) 표현에 근거한 논증하기, 5) 비교 및 대조하기 5단계로 구성한 다음, 연속된 홀수의 합은 제곱수임을 주제로 수업을 설계하였다. 그리고 실제 수업 과정에서 수학적 논증을 강조한 수업이 어떻게 구현되는지 수업의 흐름을 단계별로 분석하였다. 본 연구의 결과를 바탕으로 초등학교에서 수학적 논증을 강조한 수업의 시사점을 논의하였다.

알파인 스킹 시 카빙 턴과 베이직 패러렐 턴 간의 신체중심 및 하지관절의 운동학적 패턴 비교 (Comparisons of Center of Mass and Lower Extremity Kinematic Patterns between Carved and Basic Parallel Turn during Alpine Skiing)

  • 김주년;전현민;류시현;하성희;김진해;류지선;박상균;윤석훈
    • 한국운동역학회지
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    • 제24권3호
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    • pp.201-207
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    • 2014
  • This study investigated the center of mass and lower extremity kinematic patterns between carved and basic paralell turn during alpine skiing. Six experienced skiers (age: $20.67{\pm}4.72yrs$, body mass: $72.67{\pm}7.15kg$, height: $171.00{\pm}5.51cm$) participated in this study. Each skier were asked to perform carved and basic paralell turn on a $22.95^{\circ}$ groomed slope. Each turn was divided into the initiation phase, steering phase 1 and 2. The results of this study show that the carved turn spent significantly less running time than basic paralell turn at all three phases (p<.05). Also vertical displacement of the center of mass was significantly greater in carved turn at all three phases, whereas inward leaning angle of the center of mass was significantly greater in carved turn at the steering phase 1 and 2 (p<.05). Bilateral knee and hip joint angle were significantly greater in basic paralell turn at the initiation phase and the steering phase 2 (p<.05). On the other hand, left knee and hip joint angle were significantly greater in basic paralell turn at the steering phase 1 (p<.05). In order to perform successful carved turn, we suggest that skiers should coordinate bilateral knee and hip joint angles to adjust the center of mass, depending on three ski turn phases.

당류를 친수기로 한 비이온성 계면활성제계의 상거동(제2보) - 슈크로오스 팔미테이트/알칸올/물 계에서의 상거동 - (The Phase Behavior of Nonionic Surfactants having Sucrose as Hydrophilic Group(II) - The Phase Behavior of Sucrose Monopalmitate/Alkanol/Water System -)

  • 이향우;이진희;남기대
    • 공업화학
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    • 제8권2호
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    • pp.246-251
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    • 1997
  • 당류를 친수기로 한 슈크로오스 모노팔미테이트에 대한 3성분계 즉, 슈크로오스모노팔미테이트/알칸올/물계에서의 상거동을 각 조성에 따라 조사하였다. 미셀영역에서 여러 액정영역에 이르기까지 각 성분의 조성을 변화시키면서 정온 및 변온하에 여러 상의 구조를 온도조절기와 카메라가 부착된 편광현미경으로 비교 관찰하였다. 극성물질인 알칸올의 탄소수 증가에 따른 3성분계에서의 상거동을 관찰한 결과, 헥산올<옥탄올<데칸올 순으로 비교적 넓은 영역에서 비등방성의 여러 액정상이 존재하였으며, 이를 토대로 에멀젼이나 가용화계의 포뮬레이션에 적용할 수 있다.

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COVID-19 폐렴의 다양한 CT 영상 소견: 급성 폐포 손상과 기질화 폐렴 (The Spectrum of CT Findings of COVID-19 Pneumonia: Acute Alveolar Insult and Organizing Pneumonia as Different Phases of Lung Injury and Repair)

  • 김윤수;강웅래;김영환
    • 대한영상의학회지
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    • 제82권2호
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    • pp.359-370
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    • 2021
  • 목적 증상이 있는 123명의 coronavirus disease 2019 (이하 COVID-19) 환자에서 흉부 CT 병변의 소견과 일련의 변화를 분석하였다. 대상과 방법 2020년 2월 19일부터 4월 7일까지 총 123명의 COVID-19 환자(남성, 44명; 여성, 79명; 평균 연령 59.2 ± 18.6)를 후향적으로 연구하였다. 총 234개의 CT 스캔을 검토하여 패턴[급성 폐포 손상(acute alveolar insult) 패턴: 간유리음영, 돌조각보도모양, 혼합된 패턴, 또는 폐경화; 기질화 폐렴(organizing pneumonia) 패턴: 소엽주위 패턴, 띠 음영, 곡선형 음영, 역달무리 음영, 또는 소결절경화; 호전형 패턴: 순수 간유리음영, 잔존 곡선형 음영, 또는 소결절경화]과 폐 이상의 연속적인 변화를 분석하였다. 피어슨 카이 제곱 검정과 피셔의 정확 검정을 사용하여 시간 경과에 따른 급성 폐포 손상 패턴, 기질화 폐렴 패턴, 호전형 패턴의 비율을 비교하고, 패턴과 질병 심각도 간의 연관성을 분석하였다. 결과 초기 입원군(증상 발병 후 0~10일)의 CT 패턴은 급성 폐포 손상 패턴(87%) 이 가장 많았고, 후기 입원군(10일 이상)에서는 기질화 폐렴 패턴(45.7%), 퇴원군(퇴원 시 및 퇴원 후)에서는 호전형 패턴(47.2%; 84.8%)이 가장 많았다. 시간 경과에 따른 우세한 CT 패턴에 대한 비율의 차이는 통계적으로 유의하였다(p < 0.001, 피어슨 카이 제곱 검정). 패턴과 질병 중증도 간에 통계적으로 유의한 연관성은 발견되지 않았다(p = 0.055, 피셔의 정확 검정). 후속 CT 스캔에서 병변의 섬유화는 관찰되지 않았다. 결론 COVID-19 환자의 연속적 CT 스캔은 COVID 폐렴의 폐 손상 및 복구의 단계로서 다양한 CT 영상 소견을 보여주었다.

냉간 압축 성형한 Mg3Sb2 열전재료의 고상 반응 소결 (Solid state reactive sintering of cold pressed thermoelectric Mg3Sb2)

  • 김인기;장경욱;오한준
    • 한국결정성장학회지
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    • 제24권4호
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    • pp.176-182
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    • 2014
  • 상온 압축 성형 후 고상 반응 소결 공정을 통하여 $Mg_3Sb_2$ 소결체를 제조하고자 하였다. Mg과 Sb의 성분의 몰비와 반응온도에 따른 결정상의 변화를 조사하였다. 773~843 K에서 얻어진 고상반응 소결체들은 전형적인 $Mg_3Sb_2$ 결정상을 형성하였으나 소결체의 위치에 따라 약간 다른 상적 구성을 보였다. 소결체 하단 부위에서 전형적으로 얻어지는 결정상이 얻어졌으며 823 K 온도에서는 Mg : Sb = 3.15 : 1.85 조성일 때, 843 K 온도에서는 Mg의 몰 수가 3.10 이상인 모든 조성에서 ${\alpha}-Mg_3Sb_2$ 상과 정확히 일치하는 결정상이 얻어졌다. 미량 남아있는 Mg 성분은 응고 후 냉각 시 ${\alpha}-Mg_3Sb_2$ 상으로부터 석출된 것으로 보인다.

DEVS 형식론을 이용한 다중프로세서 운영체제의 모델링 및 성능평가

  • 홍준성
    • 한국시뮬레이션학회:학술대회논문집
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    • 한국시뮬레이션학회 1994년도 추계학술발표회 및 정기총회
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    • pp.32-32
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    • 1994
  • In this example, a message passing based multicomputer system with general interdonnedtion network is considered. After multicomputer systems are developed with morm-hole routing network, topologies of interconecting network are not major considertion for process management and resource sharing. Tehre is an independeent operating system kernel oneach node. It communicates with other kernels using message passingmechanism. Based on this architecture, the problem is how mech does performance degradation will occur in the case of processor sharing on multicomputer systems. Processor sharing between application programs is veryimprotant decision on system performance. In almost cases, application programs running on massively parallel computer systems are not so much user-interactive. Thus, the main performance index is system throughput. Each application program has various communication patterns. and the sharing of processors causes serious performance degradation in hte worst case such that one processor is shared by two processes and another processes are waiting the messages from those processes. As a result, considering this problem is improtant since it gives the reason whether the system allows processor sharingor not. Input data has many parameters in this simulation . It contains the number of threads per task , communication patterns between threads, data generation and also defects in random inupt data. Many parallel aplication programs has its specific communication patterns, and there are computation and communication phases. Therefore, this phase informatin cannot be obtained random input data. If we get trace data from some real applications. we can simulate the problem more realistic . On the other hand, simualtion results will be waseteful unless sufficient trace data with varisous communication patterns is gathered. In this project , random input data are used for simulation . Only controllable data are the number of threads of each task and mapping strategy. First, each task runs independently. After that , each task shres one and more processors with other tasks. As more processors are shared , there will be performance degradation . Form this degradation rate , we can know the overhead of processor sharing . Process scheduling policy can affects the results of simulation . For process scheduling, priority queue and FIFO queue are implemented to support round-robin scheduling and priority scheduling.

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Studies on the Ore Mineralogy and Litho-geochemistry of the Sheba Deposit, Barberton Greenstone Belt, South Africa

  • Altigani, Mohammed Alnagashi Hassan
    • 자원환경지질
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    • 제54권2호
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    • pp.213-232
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    • 2021
  • Ore criteria at the Sheba Deposit indicate orogenic mineralization type. Rocks and mineral assemblages suggest low formation-temperature of green-schist facies. Pyrite found in two generations; Type1 is irregular grains, contains higher arsenic and gold contents, compared to the relatively younger phase Type2 pyrite, which is composed of euhedral grains, found adjacent to late quartz-carbonate veins or at rims of type1 pyrite. Two gold generations were identified; type1 found included in sulphides (mainly pyrite). The second gold type was remobilized (secondary) into free-lodes within silicates (mainly quartz). Gold fineness is high, as gold contains up to 95 wt. % Au, Ag up to 3.5 wt. %, and traces of Cu, Ni, and Fe. Pyrite type2 contains tiny mineral domains (rich in Al, Mn, Hg, Se, Ti, V, and Cr). Zoning, and replacement textures are common, suggesting multiple mineralization stages. The distribution and relationships of trace elements in pyrite type2 indicate three formation patterns: (1) Al, Mn, Hg, Se, Ti, V, Cr, and Sn are homogeneously distributed in pyrite, reflecting a synchronous formation. (2) As, Ni, Co, Zn, and Sb display heterogeneous distribution pattern in pyrite, which may indicate post-formation existence due to other activities. (3) Au and Ag show both distribution patterns within pyrite, suggesting that gold is found both in microscopic phases and as chemically bounded phase.

Additive 공정을 이용한 미세 피치용 니켈 메탈마스크의 제조 및 특성평가 (Fabrication and Characterizations of Nickel Metal Mask with fine Pitch by Additive Process)

  • 박의철;임준형;김규태;박시홍;황수민;심종현;정승부;김봉수;주진호
    • 한국전기전자재료학회논문지
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    • 제20권11호
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    • pp.925-931
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    • 2007
  • We successively fabricated the Ni metal mask by additive method and evaluated the effects of wetting agents addition on the microstructure, hardness, and friction coefficient. In the process, the additive patterns with fine hole and pitch were made by photolithography technique and subsequently Ni plate was electroformed on the patterns. We found that the microstructure and mechanical properties were significantly varied when the different combinations of the wetting agents were used. When the wetting agents of both SF-1 and SF-2 were added, the microstructure consisted of crystal and amorphous phases, the grain size reduced to 5-40 nm, the RMS value decreased to 11.4 nm and the wear resistance improved. In addition, the hardness was as high as 638 Hv which is higher than that of commercial stainless steel mask and this improvement is probably due to the presence of amorphous Phase and fine grain size. The improvement of the wear resistance can provide a higher reliability and a longer service life.

시뮬라크르 관점에서의 한국적 패션디자인 분석 (Analysis of Korean Fashion Design Seunghee Suh from the Viewpoint of Simulacre)

  • 서승희;김한나
    • 패션비즈니스
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    • 제23권5호
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    • pp.19-30
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    • 2019
  • The aim of this study is to analyze the stage of image change in Korean fashion design in regards to the simulacre of Jean Baudrillard. The changing phases of Korean fashion design are as follows: First, the initial stage involved simple imitation, which replicated the original as much as possible, it expressed the basic composition of Hanbok, flat cut and rich silhouette, the color scheme of traditional colors, traditional patterns, materials, and traditional ornaments. In the second stage, the subject matter intervened to distort and transform from the original, the basic composition and structure of the Hanbok were barely maintained, they were either removed or part of the structure modified or expressed using modern materials and patterns. The third stage, were based on reality but differed from reality through subject and imagination, and only left a part of the basic composition of Hanbok, and were expressed through the partial modification of the elements of the Hanbok, for instance the silhouette, skirt waist, collar and breast-tie. The fourth stage of pure simulacre, which refers to a new image with complete independence regardless of the reality. This stage differed from the basic structure and composition of Hanbok, and showcased traditional Korean image of Korea's unique cultural elements, such as hanbok or crafts and artworks, in a modern fashion with a modern sense and practicality.

칸딘스키 추상회화의 조형적 특성을 응용한 의상 디자인 개발 (Development of Fashion Design Based on the Formative Characteristics of Wassily Kandinsky's Abstraction Paintings)

  • 임혜순;둥페이
    • 한국의상디자인학회지
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    • 제18권3호
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    • pp.145-163
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    • 2016
  • This paper analyses Wassily Kandinsky's abstract paintings. this paper aims to discuss phases of Kandinsky's works as well as their formative characteristic theory. Practically, with formative characteristics in Kandinsky's paintings such as point, line, plane, form and color, this paper presents four sets of costumes. Among which, geometric patterns are intensively collaged as the formative characteristic of "point" calls for; crossed necklines and waistlines are applied as the characteristic of "lines" represents; plane and solid patterns are adopted as the main parts and ornaments as both the characteristic of "plane" and that of "form" claim; three primary colors - red, blue and yellow - are introduced as the characteristic of "color" depicts. Artificial leathers are used as the main fabric, patchwork and draping as so in technology. Therefore, with the theoretical and practical efforts, this paper aims to seek the interdisciplinary possibilities between paintings and fashion arts, and in order to develop several fashion designs representing modern aesthetics with their unique characteristics.

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