• 제목/요약/키워드: Primary reflection

검색결과 101건 처리시간 0.025초

소수 나눗셈 수업의 계획, 실행, 비평 과정에서 초등교사의 성찰과 실천에 관한 사례 연구 (A Case Study on Reflection and Practice of an Elementary School Teacher in the Process of Planning, Executing and Criticizing a Lesson on Division with Decimals)

  • 김상미
    • 한국수학교육학회지시리즈C:초등수학교육
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    • 제21권3호
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    • pp.309-327
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    • 2018
  • 이 연구는 소수 나눗셈 수업을 중심으로 초등교사의 수업 성찰과 실행에 관한 사례 연구이다. 초등교사가 수학수업을 계획하고 실행하고 동료교사들과 자신의 수업을 비평하는 과정에서 어떤 고민을 하고 있으며 그 초점은 어떻게 변화해 가는지를 밝히고자 하였다. 수업을 계획하는 교사, 수업을 실행하는 교사, 동료교사와 자신의 수업을 비평하는 교사로 구분하고, 수학 목표, 과제의 실행, 수학적 표현, 수학적 담론, 질문의 설정, 개념적 이해와 절차적 능숙함, 생산적인 어려움, 학생 사고의 증거 활용 등의 8가지 측면을 따라 각 시기의 초등교사의 성찰과 실천을 분석하였다.

주파수-파선변수 영역에서 음원 및 수신기 고스트 제거를 통한 전통적인 해양 탄성파 자료의 광대역 자료처리 (Broadband Processing of Conventional Marine Seismic Data Through Source and Receiver Deghosting in Frequency-Ray Parameter Domain)

  • 김수민;구남형;이호영
    • 지구물리와물리탐사
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    • 제19권4호
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    • pp.220-227
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    • 2016
  • 해양 탄성파 탐사를 통해 취득한 자료에는 지하 매질에서 반사되어 오는 신호뿐만 아니라 해수면에서 되반사되어 발생하는 고스트가 존재한다. 고스트는 특정 주파수 성분을 약화시켜 탄성파 자료의 시간 해상도를 저하시킨다. 고스트를 효과적으로 제거하기 위해서는 정확한 고스트의 지연시간과 해수면의 반사계수가 요구된다. 고스트 지연시간은 해수면의 상하 움직임, 에어건과 스트리머의 움직임 및 벌림(offset) 거리 등에 의해 변하며, 해수면의 반사계수도 주파수, 평면파의 입사각 그리고 해상 상태에 따라 변한다. 이러한 영향을 고려한 고스트 지연시간을 추정하기 위하여 이 연구에서는 고스트 제거 트레이스 및 이의 자기상관 자료의 L-1 norm, L-2 norm 그리고 첨도(kurtosis)를 비교하였다. 자기상관자료의 L-1 norm을 계산하여 고스트 지연시간을 추정하는 것이 오차가 가장 적게 발생하였다. 현장자료의 파고를 고려하고 키르히호프 근사식을 이용하여 해수면의 반사계수를 계산하여 음원 및 수신기 고스트 제거에 적용하였다. 고스트를 제거함으로써 약화된 주파수 성분을 복원하였으며 시간 해상도가 향상된 구조보정 단면을 얻었다.

Image-Quality Enhancement for a Holographic Wavefront Color Printer by Adaptive SLM Partitioning

  • Hong, Sunghee;Stoykova, Elena;Kang, Hoonjong;Kim, Youngmin;Hong, Jisoo;Park, Joosup;Park, Kiheon
    • Journal of the Optical Society of Korea
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    • 제19권1호
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    • pp.29-37
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    • 2015
  • The wavefront printer records a volume-reflection hologram as a two-dimensional array of elemental holograms from computer-generated holograms (CGHs) displayed on a spatial light modulator (SLM). The wavefront coming from the object is extracted by filtering in the spatial-frequency domain. This paper presents a method to improve color reproduction in a wavefront printer with spatial division of exposures at primary colors, by adaptive partitioning of the SLM in accordance with the color content encoded in the input CGHs, and by the controllable change of exposure times for the recording of primary colors. The method is verified with a color wavefront printer with demagnification of the object beam. The quality of reconstruction achieved by the proposed method proves its efficiency in eliminating the stripe artifacts that are superimposed on reconstructed images in conventional mosaic recording.

국민학교 환경교육의 효율적 지도에 관한 연구 (A Study on the Effective Teaching Method for the Environmental Education in Korean Primary School)

  • 차주혁;김병우
    • 한국환경교육학회지:환경교육
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    • 제7권1호
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    • pp.30-45
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    • 1994
  • This study was conducted to investigate the concern of the primary school teachers and the teaching situation about the environmental education through questionnaire survey on the effective environmental education. The results of questionnaire were analysed and discussed to provide the effective teaching method for the environmental education. The result of this study is as follows. 1. It was found that teachers want to teach environmental lessons as a special subject, and the content of the environmental lessons in textbook was not enough in quantity, the living waste was the most serious ploblem. Owing to the lacking in materials for the lectures on environmental education, most teachers collect the material depending on the mass communication. Also they were more interested in the environmental lessons rather than the other lessons in textbook. But because of the lacking in administrative assistance, they have difficulty in conducting the effective environmental education. 2. The teaching method of the environmental education in most primary schools was a all together-type lecture in classroom. Owing to conducting the environmental education for the knowledge than the action through the extra activity, it was difficult to expect the effect of the environmental education. Also the rate of using the reflection materials which can be improved the studying effect was very low. 3. For the effective environmental education most teachers wanted the spot learnings and the case studies and teacher education and training to get an special knowledge for environmental education. The effective evaluation method for children's environmental education is to present the results by environmental experiences and practices and to formulate a system education is organized for the effective management and activation of environmental education. 4. By practising the seasonal spot learnings, students need to change of learning method and to realize the importance of environment through own self-experiences. 5. In the future, it is desirable that researching of an environmental education is offered the effective practising teaching method which is improving the development of customs and functions, cultivation of the sense of value, ability to solve the problem, to determine the intention as well as the survey on the real situation and the consciousness about environmental education.

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유행인가? 실행(Praxis)인가? - 가족연구에서의 다문화가족 담론분석과 성찰 - (Trends or Praxis? - Discourse Analysis and Reflection of Multicultural Families in Family Studies -)

  • 최연실
    • 가정과삶의질연구
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    • 제27권6호
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    • pp.171-187
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    • 2009
  • The purpose of this study is to identify and illustrate academic trends that can be gleaned from family studies on multicultural families in Korea, and to gain a suggestion of the relatedness between discourse and practice by reviewing research in that field. The results of discourse analysis are as follows: First, research on multicultural families in family studies set limited focal subjects. Second, the research accepts assimilationism as a primary multicultural policy set forward by the Korean Government. Third, the research reflects a more or less conservative consciousness of family maintenance. Fourth, there have been some changes in perspectives from the perception of immigrant women in multicultural families as passive minorities to more active agents. Lastly, the research perceives family life in multicultural families as a project for practice.

백인 여성과 아시아 여성의 신체비율의 비교 연구 -Petite 사이즈를 중심으로- (Comparisons of Body Proportions between Caucasian and Asian Women -Focused on Petite Size-)

  • 김선화
    • 복식문화연구
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    • 제6권4호
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    • pp.238-246
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    • 1998
  • According to several pilot tests, petite women have their own body proportion which is not simply an overall diminutive reflection of the proportion of Misses sizes. Apparel manufacturers and pattern companies do not consider racial differences nor do they consider petite women's own specific body proportions in their size categories to produce petite garments. The primary objectives of this study was to describe the petite women's body proportions especially the differences between Asian and Caucasian petite women and to compare their body proportions to the average body figure. A physical body measurement chart was developed and revised through a pretest. Sixty subjects, thirty for each group of Asian and Caucasian. They were landmarked using an anthropometric instrument and photographed using the method of somatography for analysis of body proportions. Data were analyzed by t-test for a description of the petite subject's body proportion. The results of this study indicated that the Caucasian subjects had generally a longer lower torso than tehAian subjects in their body proportions. both subject groups had differnt body proportions from the aerage body figure.

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Wideband Double Dipole Quasi-Yagi Antenna Using a Microstrip-to-Slotline Transition Feed

  • Ta, Son Xuat;Park, Ikmo
    • Journal of electromagnetic engineering and science
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    • 제13권1호
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    • pp.22-27
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    • 2013
  • This paper describes a wideband double dipole quasi-Yagi antenna fed by a microstrip-to-slotline transition. The transition feed consists of a microstrip radial stub and a slot radial stub, each with the same angle of $90^{\circ}$ but with different radii, to achieve wideband impedance matching. Double dipoles with different lengths are utilized as primary radiation elements to enhance bandwidth and achieve stable radiation patterns. The proposed antenna has a measured bandwidth of 3.34~8.72 GHz for a -10 dB reflection coefficient and a flat gain of $6.9{\pm}0.6$ dBi across the bandwidth.

Reflecting Critical Pedagogy: Its Application to EFL Contexts and Criticism

  • Jeon, Ji-Hyun
    • 영어어문교육
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    • 제15권3호
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    • pp.59-81
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    • 2009
  • The primary goal of this paper was to develop a critical point of view to critical pedagogy when applied to EFL contexts. Critical pedagogy is more concerned about how language can affect personal and social change of teachers and students than it is with how to teach language effectively or in ways that encourage critical thinking on the part of teacher and students. For this goal, this paper introduces the definition, emergence and major constructs of critical pedagogy in a broad way at first. Then, this paper presents how critical pedagogy has an impact on ELT, focusing on how critical pedagogy is applied in ELT contexts and why the application of critical pedagogy in EFL can be criticized, through the review of empirical studies. Reflection of Korean English teaching situation and applicational difficulties of critical pedagogy in Korean ELT are followed.

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탄성파 수직반사자료의 역산 연구 (A Study on Inversion of Seismic Normal Reflection Data)

  • 양동우;양승진;장성형
    • 자원환경지질
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    • 제29권5호
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    • pp.629-637
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    • 1996
  • In this paper a numerical experiment is conducted to determine the low acoustic impedance of a thin oil or gas reservoir from a seismogram by using the generalized linear inversion method. The seismograms used are normal incident synthetic seismograms containing p-wave primary reflections, multiples, and peg-leg multiples on the layers consisting of oil-, gas-, water-filled sandstone incased in shales. In this experiment the acoustic impedance, the location of reservoir boundary, thickness, and source wavelet are assumed initially and revised iteratively by the least-squares-error technique until the difference between the seismogram and calculated one is very small. This experiment shows that the acoustic impedance and thickness, about 10 m thick, can be determined by the inversion.

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패션기업의 패션정보 활용 (Fashion Firm's Utilization of Fashion Information)

  • 정송향
    • 한국의류산업학회지
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    • 제6권6호
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    • pp.699-706
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    • 2004
  • In today's fashion industry, directions for new products and high value added of fashion goods, product changes according to cycles, the shortening of life cycles, added value, planned obsolescence, and presentation is focused on fashion trends that will be selected by many consumers at the point of selling time. Therefore fashion information poses great importance and its weight is growing bigger everyday. Fashion information recognized to be important is reflected practically in the prediction of fashion changes in the fashion industry; especially, it is the first stage of the merchandising process that is the course of new product development. Presently, with some differences according to the size and specialized area of a firm, domestic fashion menufacturers obtain information from sales data of competing brands and their own, market information, consumer information based on primary data, shared fashion trend information given by domestic fashion information providing companies. Firms can not produce differentiated images and product concepts using such shared information. Although the types, importance and reflection of used information vary according to merchandising processes, all experts engaging in the merchandising of fashion products use the same shared information.