• 제목/요약/키워드: Seasonal changes

검색결과 1,133건 처리시간 0.03초

계절의 변화 멀티미디어 자료 활용이 중학생의 개념 변화에 미치는 효과 (The Effect of Using Multimedia Material of Seasonal Change on Middle School Students' Conceptual Changes)

  • 정정인;심기창;김희수
    • 한국지구과학회지
    • /
    • 제25권7호
    • /
    • pp.545-557
    • /
    • 2004
  • 본 연구는 중학생들의 계절의 변화에 관한 선개념의 유형을 파악하고 멀티미디어 학습 자료를 개발하여 그 수업이 계절의 변화에 대한 개념에 어떠한 변화를 주는지 알아보는데 목적이 있다. 계절의 변화 개념을 알아보기 위한 검사지는 10문항을 개발하였다. 대상자는 중학교 3학년 80명(실험반 57명, 통계반 23명)으로 2차시에 걸친 수업을 실시하였다. 실험반에는 멀티미디어 활용수업이 투여된 반면 통제반에는 전통적인 수업이 투여되었다. 그 결과, 본 연구에서 활용된 멀티미디어 자료는 학생들의 개념변화에 효과가 있음을 보였다.(p$<$0.01). 또한, 개념의 변화를 상세히 알아보기 위하여 6단계로 분류하여 분석한 결과, 멀티미디어 활용수업은 전통적 수업모형에 비하여 개념이 없는 학습자의 과학적 개념을 형성하거나, 비과학적 개념을 과학적 개념으로 발전시키는데 효과적일 뿐만 아니라 과학적 개념을 더욱 더 정교화 시키는데도 효과적이었다.

Lakatos의 방법론에 의한 예비 중등 교사의 계절 변화에 대한 설명의 근원 연구 (The Sources of Preservice Secondary Teachers' Explanations about Seasonal Changes Investigated with the Lakatosian Methodology)

  • 오준영;강용희;이효녕;김용기
    • 한국지구과학회지
    • /
    • 제27권4호
    • /
    • pp.374-389
    • /
    • 2006
  • 이 연구는 예비 중등 교사들을 대상으로 Lakatos의 방법론에 따라서 "계절 변화의 설명"에 대한 대안 모형을 조사하였다. 조사대상은 사범대학 과학교육학부 74명이다. 조사 결과 계절 변화에 대한 예비 중등 교사들의 설명은 과학적 모형과 불일치하는 대안 모형들을 가지고 있었다. 이러한 명백한 불일치의 대안 개념은 어떤 일관성 있는 방향으로, 자신들이 가지고 있는 대안 모형의 핵심 신념을 사용한다고 가정함으로서 설명되어 진다고 우리는 주장한다. 따라서 이 연구에서는 예비 교사들의 대안 모형을 극복하기 위해서 먼저 그들이 가지고 있다고 가정할 수 있는 핵심 신념들과 가능한 근원들을 알아보는 것이다. 그러한 근원들 중에서 교과서가 예비 교사의 대안 모형의 근원을 제공할 가능성을 배제할 수는 없다.

발생학습 전략의 적용이 계절변화 관련 지구과학개념 변화에 미친 효과 (The Effects on Earth Science Concepts about Seasonal Changes by Generative Learning Strategy)

  • 정진우;윤상화;이항로
    • 한국지구과학회지
    • /
    • 제24권3호
    • /
    • pp.160-171
    • /
    • 2003
  • 본 연구에서는 계절 변화에 관련된 개념 유형을 분석하고, 관련 개념들에 관한 토의에 의해 인지갈등을 해소하는 방법을 강조한 발생학습 전략의 적용 효과를 알아보고자 하였다. 계절변화 관련 지구과학 개념 유형은 100가지 였으며, 그 중에서 66가지는 오개념을 포함한 비과학적 개념 유형이었다. 계절변화에 관련된 개념 평가도구는 R&D과정과 2번의 현장검증을 거쳐 개발되었다. 실험집단에는 지구과학개념 유형과 인지갈등을 반영한 4단계의 발생학습 전략을 적용하였다. 한편 통제집단에는 전통적인 교수 학습 전략을 적용하였다. 유의수준 .05에서 공변량분석을 실시한 결과 두 집단 간에는 유의미한 차이가 있는 것으로 나타났다. 이러한 연구 결과는 계절변화와 관련된 오개념을 지구과학적 개념으로 변화시키는 데 발생학습전략이 하나의 가능한 대안이 될 수 있음을 의미하는 것으로 볼 수 있다.

Seasonal Changes in Jasmonic Acid Contents of Yam Leaves

  • Chang, Kwang-Jin;Mitsuru Hayashi;Michilo Onjo
    • Plant Resources
    • /
    • 제1권1호
    • /
    • pp.49-52
    • /
    • 1998
  • This study confirmed that the initiation time of tuberization was well consistent with the cativation time of JA. The consistency was also cinfirmed in the tuberization of yam plants under the altered condition of natural day length. The final yield of JA from 500g fresh leaves was $89.3{\mu}g$.

  • PDF

광양만 장피밭에 서식하는 농어 ( Lateolabrax Japonicus ) 의 식성 (Feeding Habits of Lateolabrax Japonicus in the Eelgrass ( Zostera Marina ) Bed in Kwangyang Bay)

  • 허성회;곽석남
    • 수산해양기술연구
    • /
    • 제34권2호
    • /
    • pp.191-199
    • /
    • 1998
  • Feeding habits of Lateolabrax Japonicus collected from the eelgrass bed in Kwangyang Bay from January 1994 to December 1994 were studied. L. Japonicus was a carnivore which consumed mainly amphipods (gammarid amphipods and caprellid amphipods), crabs, caridean shrimps and copepods. Its diets included small quantities of fishes, mysids, polychaetes, tanaids and isopods. Three distinct ontogenetic feeding groups were noted : (1) 1~2 cm SL individuals preyed heavily on copepods. (2) 2~15 cm SL individuals preyed heavily on amphipods. (3) individuals over 15 cm SL preyed heavily on crabs, caridean shrimps and fishes. L. Japonicus showed seasonal changes in prey composition. These changes were not caused by seasonal changes in food availability, but by changes in the size composition of L. Japonicus occurred in the eelgrass bed.

  • PDF

Observation of Water Volume Changes of Rivers in Amazon Forests from Multi-temporal JERS-1 SAR Images

  • Takako, Sakurai-Amano;Takagi, Mikio
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
    • /
    • pp.454-459
    • /
    • 2002
  • We have developed a new method to visualize river networks in tropical rain forests from JERS-1 SAR images. This method compresses river information in an original SAR image to a small image displaying wide rivers as dark objects in real size and narrower rivers as bright objects showing brightness level as an indicator of the discharge. We applied this method to 476 images of Amazon forests, 13 observations for path 415 data and 11 observations for path 416 data between 1993 and 1997. We confirmed that a change observed in a preliminary experiment was certainly a part of seasonal changes. The changes roughly correspond to the monthly precipitation changes. Through a simple digital analysis although qualitative, we also detected subtle but consistent regional differences among minor tributaries that belong to a major tributary basin.

  • PDF

Assessment of seasonal variations in water quality of Brahmani river using PCA

  • Mohanty, Chitta R.;Nayak, Saroj K.
    • Advances in environmental research
    • /
    • 제6권1호
    • /
    • pp.53-65
    • /
    • 2017
  • Assessment of seasonal changes in surface water quality is an important aspect for evaluating temporal variations of river pollution due to natural or anthropogenic inputs of point and non-point sources. In this study, surface water quality data for 15 physico-chemical parameters collected from 7 monitoring stations in a river during the years from 2014 to 2016 were analyzed. The principal component analysis technique was employed to evaluate the seasonal correlations of water quality parameters, while the principal factor analysis technique was used to extract the parameters that are most important in assessing seasonal variations of river water quality. Analysis shows that a parameter that is most important in contributing to water quality variation for one season may not be important for another season except alkalinity, which is always the most important parameters in contributing to water quality variations for all three seasons.

단풍나무속 식물 4 종에 대한 엽록소함량과 광합성율의 계절적 변화 (Seasonal Changes of Chlorophyll Contents and Photosynthetic Rates in Four Species of Maple Trees in Korea)

  • Choe, Hyun-sup;Hye-Jeong Lee
    • The Korean Journal of Ecology
    • /
    • 제18권1호
    • /
    • pp.137-146
    • /
    • 1995
  • Acer pseudo-sieboldianum, A. ginnala, A. negundo and A. saccharinum were selected as materials for the studies on the seasonal fluctuation of chlorophyll content and photosynthetic rates. In all the four species during the growing season except in October, the principal component that determined the total chlorophyll content was chlorophyll a. Content of chlorophyll b increased with leaf age, but that of chlorophyll a decreased. In contrast to A. saccharinum and A. pseudo-sieboldianum which showed their maximum chlorophyll content in June, A. negundo, which showed the highest chlorophyll content of the four species, exhibited its maximum chlorophyll content in July, whereas September in the case of A. ginnala. The fluctuation of chlorophyll content was similar to that of air temperature, and it increased till July. But chloprophyll content showed a significant relationship in early stage of leaf development, and there could be any interdependence between them in accordance with the seasonal change, no longer. In all four species light compensation points decreased in accordance with the seasonal change, and the maximum photosynthetic rates were obtained in August. Respiratory rates were shown no significant difference among species, and they decreased according to the adbance of season.

  • PDF

Seasonal acclimation in sudomotor function evaluated by QSART in healthy humans

  • Shin, Young Oh;Lee, Jeong-Beom;Kim, Jeong-Ho
    • The Korean Journal of Physiology and Pharmacology
    • /
    • 제20권5호
    • /
    • pp.499-505
    • /
    • 2016
  • The quantitative sudomotor axon reflex testing (QSART) is a classic test of routine postganglionic sudomotor function. We investigated sudomotor function by QSART after summer (July 2012) and winter (January 2013) seasonal acclimation (SA) in the Republic of Korea. QSART with acetylcholine (ACh) iontophoresis were performed to determine directly activated (DIR) and axon reflex-mediated (AXR1, 2) sweating rate. Onset time of axon reflex, activated sweat gland density (ASGD), activated sweat gland output (ASGO), tympanic and skin temperatures ($T_{ty}$, $T_{sk}$), basal metabolic rate (BMR), and evaporative loss volume changes were measured. Tympanic and mean body temperature (${\bar{T}}_b$; calculated from $T_{ty}$, $T_{sk}$) were significantly lower after summer-SA than that of winter-SA. Sweat onset time was delayed during winter-SA compared to that after summer-SA. BMR, AXR(1), AXR(2), and DIR sweat rates, ASGD and ASGO, and evaporative loss volume were significantly diminished after winter-SA relative to after summer-SA. In conclusion, changes in sweating activity measured by QSART confirmed the involvement of the peripheral nervous system in variation of sudomotor activity in seasonal acclimation.