• Title/Summary/Keyword: Seasonal change

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Analyzing Causes of Seasonal Changes Displayed by Primary Teachers at the Equator

  • Chae, Dong-Hyun
    • Journal of The Korean Association For Science Education
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    • v.29 no.7
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    • pp.759-766
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    • 2009
  • This study was conducted to examine 10 Belizean teachers' conceptions about the causes of seasonal change. This research was conducted with an integrated method using a open ended written test and an interview which included a drawing. There are four categories, explained by the teachers, as the causes of seasonal changes. They are; climate, rotation of the earth on its axis, revolution of the earth around the sun, and the tilting of earth's axis as it revolves. Most teachers misunderstood that the first of three categories was responsible for seasonal change. Second, it is more effective to use the integrated method shown in this research than to use only a written test when seriously investigating the causes and understanding of seasonal change. Third, 8 out of 10 teachers could not correctly explain the causes of seasonal change. The reasons for seasonal change seemed to be hard for the informants to understand even though it was taught in elementary, middle, high school, and college elective classes.

Studies On The Primary Production In Suyong Bay

  • Kang, Yong Joo
    • 한국해양학회지
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    • v.2 no.1_2
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    • pp.13-23
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    • 1967
  • Seasonal changes in the primary production of surface water in Suyong Bay, Pusan, were measured using a light-dark bottle method. Gross photosynthesis followed a distinct seasonal change with highest levels in spring and fall. Respiration of plankton community showed its maximum only in the late summer and early fall. Net photosynthesis of plankton community is considerably variable throughout year, but followed a seasonal change similar to gross photosynthesis. Seasonal changes in temperature and salinity are related to the seasonal change in plankton metabolism.

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How Can We Improve the Lesson on Seasonal Change?

  • Han, Je-jun;Chae, Dong-hyun
    • Journal of the Korean Society of Earth Science Education
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    • v.10 no.3
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    • pp.254-261
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    • 2017
  • This study is to investigate preconception of elementary school students and Belizean elementary school teachers and to devise experiment to understand a cause of seasonal change. An open-ended questionnaire and interviews were conducted for 91 6th grade students who didn't learn seasonal change and 10 Belizean teachers to find out preconception of seasonal change and they were categorized by using inductive analysis. They thought that the Earth's rotation, the distance between the Sun and the Earth, the Earth's revolution, pollution and climate change cause seasonal change. And it found out that these misconceptions come from difficulty in awareness of space and impreciseness of textbooks and books and so on. The experiment was designed to correct inaccurate preconception and to improve lessons of seasonal change. It is to measure a meridian altitude and a length of daytime and nighttime and to compare them. This experiment can help to understand the cause of seasonal change by measuring natural phenomenons like the meridian altitude and the change of length of daytime by model.

The Investigation of Six Grade Students' Preconceptions about the Cause of Seasonal Change (계절 변화의 원인에 대한 초등학교 6학년 학생들의 선개념 조사)

  • Chae, Dong-Hyun
    • Journal of Korean Elementary Science Education
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    • v.30 no.2
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    • pp.204-212
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    • 2011
  • This research is about the six graders' preconceptions in elementary school about a cause of the seasonal change before learning. The result of this research is that the patterns of six graders's preconceptions in elementary school are earth's rotation, earth's revolution, the distance between the earth and the sun and the location factor between the sun and our country, which are mixed up with two more things. Especially many patterns of students explain the seasonal change of our country using the change of location of our country by earth's rotation, the location factor between the earth and the sun and the distance between the earth and the sun by earth's revolution.

INFERENCE ON THE SEASONALLY COINTEGRATED MODEL WITH STRUCTURAL CHANGES

  • Song, Dae-Gun;Cho, Sin-Sup
    • Journal of the Korean Statistical Society
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    • v.36 no.4
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    • pp.501-522
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    • 2007
  • We propose an estimation procedure that can be used for detecting structural changes in the seasonal cointegrated vector autoregressive model. The asymptotic properties of the estimates and the test statistics for the parameter change are provided. A simulation example is presented to illustrate this method and its concept.

Seasonal Changes of Shorelines and Beaches on East Sea Coast, South Korea (동해안 해안선과 해빈의 계절적 변화)

  • Kim, Dae Sik;Lee, Gwang-Ryul
    • Journal of the Korean Geographical Society
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    • v.50 no.2
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    • pp.147-164
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    • 2015
  • This study analyzed characteristics and tendencies of seasonal change on shoreline and beach with 8 beaches at East Sea coast by topographical survey for 2 years from March 2012 to February 2013. The shorelines of East Sea coast appeared that amount of seasonal change was bigger than amount of annual change. The seasonal change tendencies between Gangwon-do and Gyeongsangbuk-do coast areas existed some regional differences. To synthesize seasonal changes on 8 beaches of East Sea coast, shoreline advance and beach deposit showed clearly in summer and shoreline retreat and beach erosion showed clearly in autumn. This result is different from tendencies of seasonal change in many mid-latitude coast areas of the world, but generally corresponds with reference studies in west coast and east coast. The major factor of beach erosion showing mostly in summer is storm wave caused by typhoon. The beach erosion by storm wave also occurred in late winter. And it assumes that the beach deposit showing mostly in autumn is result of equilibrium processes of coast area against strong erosion in summer.

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A Study of Historical Seasonal Subdivision System and Modern Definitional Issue of Meteorological Seasons (전통시대 절후법과 기후표 고찰에 따른 현대 '기상계절'과 '새로운 기후표'의 제안)

  • Kim, Il-Gwon
    • Atmosphere
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    • v.26 no.1
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    • pp.185-192
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    • 2016
  • In this paper, I studied about historical seasonal subdivision system and a theory of traditional monthly order, which was used for so long from Koryo dynasty to the late of Choseon dynasty in Korean histoy. Especially, I took note of the fact that there used the table of solar terms and meteorological observation what we called the table of Kihoo-pyo in the historical Sunmyung-calendar and the Soosi-calendar during the Koryo dynasty. This table of Kihoo was developed for explaining meteorological change during a year at that time. Here are largely four elements related meteorological nature : the first is the list of 24 solar terms, and the second is 12 monthly seasonal terms and 12 monthly central terms, the third is about four right hexagon based I-ching, the fourth is 72 meteorological observations called 72-hoo. Among them, the 72-hoo system is important to know how premodern people observed natural materials including animals and plants, weather, climate about meteorological phenomena according to the seasonal change or solar terms' change during a year. I argued in this article to need developing modern new table of Kihoo system like that, in order to show common people to recognize annual meteorological change more easy and clear. I also argued to need a distinct definition of meteorological seasons from a view point of modern meteorology.

Bottom Loss Variation of Low-Frequency Sound Wave in the Yellow Sea (황해에서 저주파 음파의 해저손실 변동)

  • Kim, Bong-Chae
    • Ocean and Polar Research
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    • v.29 no.2
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    • pp.113-121
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    • 2007
  • The sound wave in the sea propagates under the effect of water depth, sound speed structure, sea surface roughness, bottom roughness, and acoustic properties of bottom sediment. In shallow water, the bottom sediments are distributed very variously with place and the sound speed structure varying with time and space. In order to investigate the seasonal propagation characteristics of low-frequency sound wave in the Yellow Sea, propagation experiments were conducted along a track in the middle part of the Yellow Sea in spring, summer, and autumn. In this paper we consider seasonal variations of the sound speed profile and propagation loss based on the measurement results. Also we quantitatively investigate variation of bottom loss by dividing the propagation loss into three components: spreading loss, absorption loss, and bottom loss. As a result, the propagation losses measured in summer were larger than the losses in spring and autumn, and the propagation losses measured in autumn were smaller than the losses in spring. The spreading loss and the absorption loss did not show seasonal variations, but the bottom loss showed seasonal variations. So it was thought that the seasonal variation of the propagation loss was due to the seasonal change of the bottom loss and the seasonal variation of the bottom loss was due to the change of the sound speed profile by season.

Analysis of the Seasonal Change in Attached Algae and Microbial Community Structure in Sediment Basin Trough of Water Treatment Plant By Using Quinone Profile and PCR-DGGE (Quinone profile과 PCR-DGGE를 이용한 정수장 침전지에서의 부착조류 및 미생물군집의 계절적 변화해석)

  • Yu, Hyun-Sun;Lim, Byung-Ran;Ahn, Kyu-Hong
    • Journal of Korean Society of Water and Wastewater
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    • v.20 no.3
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    • pp.461-467
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    • 2006
  • The seasonal change in attached algae and microbial community structure at sedimentation basin of water treatment plant was investigated by using quinone profiles and denaturing gel gradient electrophoresis (DGGE). The photosynthetic bacteria and algae contains PQ-9 and VK-1 as major quinone are major component of the total quinone fraction in attached algae and microorganisms on sedimentation basin trough. The microorganisms containing menaquinones appear to be sensitivity to the change in temperature than those containing ubiquinones. The plot of the mole fraction of dominant quinone species ($f_d$) to the DQ values showed higher sensitivity to the seasonal change in the microbial community structure. The results indicated that quinone and DGGE are useful tool for the evaluation of the changes in the microbial community structure.

The Change of Seasonal Trend Appeared in Wintertime Daily Mean Temperature of Seoul, Korea (서울의 겨울철 일평균 기온에 나타난 계절 추이와 변화)

  • Park, Byong-Ik
    • Journal of the Korean Geographical Society
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    • v.46 no.2
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    • pp.152-167
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    • 2011
  • This study aims to investigate the change of seasonal trend appeared in the daily normals of wintertime daily mean temperature of Seoul for 1941~1970 and 1971~2000 and the factors to affect it. The lowest temperature in wintertime is appeared in the period of the first and second ten-days of January in the daily normals for 1941~1970 and in the third ten-days of January and the first ten-days of February for 1971~2000. This means seasonal trend was changed. This change is due to the fact average temperature from 27 December to 20 January is rising much more than the wintertime mean temperature and average temperature from 21 January to 9 February less than that for two daily normals. This features are notable after 1971. The Siberian high and norther wind around the Korean Peninsula are weakened remarkably recently, so mean temperature of Seoul from 27 December to 20 January is warming much more. On the other hand, the Siberian high from 21 January to 9 February is weakened and the Aleutian low is strengthened recently and northerly is not change obviously, so temperature of Seoul is not warming so much.