• Title/Summary/Keyword: 계절 변화

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Study on the Conceptual Hierarchy for Seasonal Change (계절변화 개념 위계에 관한 연구)

  • Jung, Sun-La;Lee, Yong Bok
    • Journal of the Korean earth science society
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    • v.34 no.4
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    • pp.356-367
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    • 2013
  • We study on the concept and reason of seasonal change that 164 university students have. Subsequently the concept types on the seasonal change are classified according to the characteristics and conceptual change after teaching on astronomy. All of the students were simply checked by the questionnaire of multiple choice and essay method before learning on the subjects. And then they answered to questionnaires of similar type after one semester. By the analyzed results, we classify it to three steps of hierarchical concept structure. The first step is the cosmic perspective that is related to the Earth's condition and motion. The second step is the influence of the Earth that is directly affected by the first step. The third step is observer's perspective on the Earth depending on the second step. Among the answers, the first step is prominent and second step is rare. The answers on the reason of seasonal change show some kinds of type which are 1st, 1-2nd, 1-3rd, and 1-2-3rd step. By the result, it is arranged in sequence like as 1-3rd>1st>1-2nd>1-2-3rd type. The lowest number of students was 2nd step of the Sun's altitude and duration of daytime in pre-test. However the students of 2nd step obtained more correct scientific concept on the seasonal change after learning on the subjects, and got the higher score in the post-test than in the pre-test. We found how much important the hierarchical structure on the reason of seasonal change is. As the results, second step on the learning of the Sun's altitude and duration of daytime essentially have to teach after first step. And then third step have to teach. At last, it is sure that the students can obtain the concept of seasonal change.

Seasonal Variation in Proximate Composition, Cholesterol and $\alpha$-Tocopherol Content of 12 Species of Korean Fish (12종 어류의 일반성분조성과 콜레스테롤 및 $\alpha$-토코페롤 함량의 계절변화)

  • JEONG Bo-Young;CHOI Byeong-Dae;LEE Jong-Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.31 no.5
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    • pp.707-712
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    • 1998
  • Seasonal variation in the proximate composition, cholesterol (CHOL) and $\alpha$-tocopherol ($\alpha$-Toc) content of 12 spices of fish muscle, which caught off Tongyeong coast of the Southern Sea (Nam-Hae) from Mar. 1995 to Feb. 1996, was studied. Lipid and moisture content showed remarkable seasonal variation and there were a negative correlation between the both (r= -0,85, p<0.001), while protein and ash content unchanged almost through the sampling period. The lipid content of anchovy, hickoryshad, black sea bream, finespotted flounder sea eel, bastard, and file fish was high in Dec. Oct. Nov. Jan. Jan. Nov, respectively, and low in the season corresponding to their spawning period. However, in case of striped mullet, yellow tail, mackerel, rock fish and red sea bream, there was no correlation between their lipid content and spawning period, and thus these fishes fore considered to be affected more by water temperature and the content of their diet. CHOL content increased In :he season containing a high level of lipid, whereas $\alpha$-Toc content unchanged almost through the sampling period.

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Numerical experiments for the changes of currents by reclamation of land in Kwangyang Bay (매립으로 인한 광양만의 유동변화 수치실험)

  • 추효상
    • Journal of Environmental Science International
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    • v.11 no.7
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    • pp.637-650
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    • 2002
  • This study presents an investigation of the changes of the currents in Kwangyang Bay due to the construction of harbor, reclamation and coastal developments. Currents were simulated by the numerical experiments with a diagnostic multi-level model and using the seasonal oceanographic data of temperature, salinity and ocean current. The values of kinetic and potential energies for the currents were calculated in cases of three topographical changes; before coastal developments, the existing state and after completion of the development project in Kwangyang Bay. The changes of currents due to the coastal developments are as follow; Kinetic energies of tide induced residual currents and wind driven currents decreased by 35~40 percent and 5 percent respectively, however those of density currents increased by 10 percent since the decrease of the coastal areas. Kinetic energy of residual currents including tide induced residual currents, density currents and wind driven currents reduced by 10 percent compared with before the coastal developments. Decrease of current velocity was greatest in summer. Therefore, in summer it was assumed that the Kwangyang Bay is more easily polluted by stratification and decrease of residual current than before the coastal developments carried out.

Seasonal Variation and Production of Zooplankton in Chonsu Bay, Korea (천수만 동물플랑크톤의 계절변화와 생산량)

  • SHIM, JAE HYUNG;YUN, KU HYUN
    • 한국해양학회지
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    • v.25 no.4
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    • pp.229-239
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    • 1990
  • The zooplankton of Chonsu Bay was collected and analyzed to study the seasonal variation in species composition and abundance, and to estimated the total annual production of Copepoda. With a pronounce seasonal fluctuations in species composition and abundance, Paracalanus indicus and Corycaeus affinis predominated during summer and fall, while larger species such as Centropages abdominalis and Acartia dominated in spring. Zooplankton abundance showed the minimum in March, then increased and reached the maximum in August. It is suggested that seasonal variation of zooplankton as well as temperature. Being productive compared with other areas, the estimated total production of Copepoda was 134 g/100m$^3$/yr (dry weight).

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인공위성 원격탐사에 의한 지구 수계환경 감시

  • 박경윤
    • Water for future
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    • v.24 no.3
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    • pp.36-41
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    • 1991
  • 1960년대 초부터 미 국립항공우주국(NASA)에서 기상위성을 지구궤도에 올리면서 시작되고 우주개발 선도국들에 의해 수 없이 발사되어 지구상공을 선회하고 있는 각종 실험위성, 자원탐사위성들로부터 이전까지만해도 지엽적이고 단편적인으로 알려지던 지구환경현황들이 이제는 지구전체에 대한 시시각각의 정보로 확대되고 있다. 기상위성들에 장착된 Sensor들로는 구름과 기상현상의 분포는 물론이고 각 대양의 해수면 온도 분포들이 파악되고 있으며 식물지수에 의한 지상의 식물분포의 계절적 변화양상에서 열대림의 사막화 추세들까지도 분석된다. 특히 위성탐사에 의한 남극 오존홀 (Ozone Hole)의 확인은 최근악화 되고 있느 swlrnchs 환경문제에 대한 커다란 주의를 환기시켜 주었다. 대양의 Phytoplankton 분포가 계절에 따라 위성자료에 의해 분석되므로서 해양의 생산능력(Productivity)의 변화도 알게되고 있다. 해양수면의 높이를 측정했던 초단파(microwave)영역의 SAR 자료는 구름을 투과하여 지구표면을 전천후 Monitoring할 수 있는 다음 세대의 Sensor로 각광을 받고 있으며 앞으로 유럽과 일본, 카나다, 소련 등에서 이들 새로운 Sensor들이 탑재 될 자원탐사 위성(ERS)과 RADASAT 등의 위성이 계속해서 개발되고 있어 이들에 의한 지구환경상태 진단은 크게 각광받게 될 것이다. 그외에도 해면풍 운량, 총강우량 분포, 대기 투명도, 대기의 열수지등의 계절적 변화에 대한 인공위성자료 해석을 통하여 지구의 온난화nas제가 본격적으로 ud가되고 있다. 또한 자원탐사위성인 Landsat 과 SPOT 등의 위성에 의해서는 각대륙의 토지 이용도 변화, 토사의 이도, 지질도 작성, 입체도 제착등과 농산물수확량의 예측있어서 괄목할 만한 발전이 계속되고 있다. 더욱이 NASA와 일본, 유럽등에서 지구관측을 위해서 준비하고 있는 각종 지구관측위성(EOS)들이 실용화 될 2000년 대에는 일반 지구환경감시는 물론 수계환경 감시 체계구축에 획기적인 진전이 있을 것으로 기대된다.

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Future Projections on the Spatial Distribution of Onset Date and Duration of Natural Seasons Using SRES A1B Data in South Korea (A1B 시나리오 자료를 이용한 우리나라 자연 계절 시작일 및 지속기간의 공간 분포 변화 전망)

  • Kwon, Young-Ah;Kwon, Won-Tae;Boo, Kyung-On
    • Journal of the Korean Geographical Society
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    • v.43 no.1
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    • pp.36-51
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    • 2008
  • As the global warming has influenced on various sectors including agriculture, forestry, fisheries and health, it is essential to project more accurate future climate for an assessment of climate change impact and adaptation strategy. This study examines spatial distribution of onset dates and durations of season decomposed by applying a lowpass filtering using observed 30-year (1971-2000) data and projected 2090s data based on the IPCC SRES A1B emission scenario in South Korea. In general, the distributions of spring and winter onset date are affected by latitudes, topography and proximity to oceans. However, onset dates of summer and autumn are a little affected by proximity to oceans and topography than by latitudes. In the 2090s (2091-2100), the onset dates of spring begin about 40 days earlier and the onset dates of summer begin 25-30 days earlier as compare with present time. On the other hand, the onset dates of winter begin about 50 days later in the southern and eastern coastal area and in the southern inland. The onset dates of autumn begin about 20 days later. In the 2090s, summer duration is longer and winter duration is shorter as compare with present time at southern and eastern coastal area.

Seasonal Changes in Quality of Chonggak Kimchi Fermented at Different Temperatures (계절별.발효온도별 총각김치의 품질 특성의 변화)

  • Noh, Jeong-Sook;Kim, Hyun-Ju;Kwon, Myung-Ja;Song, Yeong-Ok
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.6
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    • pp.742-749
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    • 2009
  • In order to establish the basic scientific data on the fermentation characteristics of chonggak kimchi (CGK), we studied with CGKs prepared at different seasons and stored at various temperatures ($5{\sim}23^{\circ}C$). Changes in pH and acidity of CGK fermented at different temperatures were typical. However, acidity of summer CGK stored under $15^{\circ}C$ did not reach 1.0% since the amount of reducing sugar in the summer radish was lower by over 1% than the ones from the other seasons. Growths for Leuconostoc and Lactobacillus spp. over 8.0 logCFU/mL were observed in CGKs fermented above $10^{\circ}C$. Changes in Max G, cutting force, of CGK from different seasons were apparent. Max Gs for spring and summer CGK were decreased immediately right after storage while Max Gs for winter CGKs were increased slowly during storage. According to the results of sensory evaluation, CGKs revealed the highest overall acceptability when acidity of kimchi reached $0.7{\pm}0.1%$ under the given fermentation condition. However, CGK prepared with radish from winter or summer season tasted better than the one made in the spring. But the edible periods for winter CGKs were longer, compared with summer CGKs fermented at the same temperature. In conclusion, CGK fermented at $10^{\circ}C$ in the winter season gives a better taste with longer edible duration than the other CGKs.

Seasonal Variations of Intraocular Pressure in Normal Sapsaree Dogs (정상 삽살개 군에서의 계절별 안압 수치의 변화)

  • Chae, J. Jeremy;Jeong, Man-Bok;Choi, Joseph S.;Park, Shin-Ae;Yi, Nayoung;Kim, Won-Tae;Seo, Kang-Moon
    • Journal of Veterinary Clinics
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    • v.30 no.2
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    • pp.95-99
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    • 2013
  • This study was performed to evaluate the seasonal variation of intraocular pressure (IOP) values in normal Sapsaree dogs. Sapsaree dogs (n = 474) clinically free from ophthalmic disease were included in this study, and both eyes were examined in each dog. An applanation tonometer (Tonopen$^{(R)}$ XL) was used to measure IOP values in both eyes. Data obtained from both eyes were stratified by factors thought to affect IOP values including age, gender, hair coat type as well as season of measurement. The IOP results were compared by ANCOVA to verify the effect each factor had on IOP, and an ANOVA test followed by a Bonferroni post hoc test was used for further analysis. The overall mean ${\pm}$ SD IOP value was $19.1{\pm}3.7$ mmHg (range: 8 to 28 mmHg) in the present study. Only seasonal variation showed a significant effect (P < 0.001), on IOP values. IOP values measured in winter ($20.4{\pm}3.4$ mmHg) and summer ($17.1{\pm}3.6$ mmHg) were significantly higher and lower, respectively, than those measured in other seasons. These results suggest a seasonal variation has a significant effect on the IOP of normal dogs. This may prompt further research and possible modification of current veterinary ophthalmic references.

한국 녹용의 우수성을 말한다

  • Korea Deer Breeders Association
    • Korean Deer Journal
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    • v.13 no.3 s.66
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    • pp.44-51
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    • 2006
  • 양록 산업의 핵심 상품은 녹용이다. 녹용은 산천초목과 같이 부드럽게 형성 되어 마치 성장하는 나무의 가지와 같이 보이다가 나중에는 계절의 변화에 맞춰 날카로운 나뭇가지처럼 변모하는 것을 보게 된다. 녹용에서 녹각으로, 계절에 따라 성장기에는 위장용의 도구로, 완숙기에는 방어용 무기로 사용된다. 녹용에는 고단위 영양분의 요소들이 있다. 뿔의 형성시기에는 호르몬의 생성마저도 정지될 정도로, 모든 기운이 모여서 뿔의 성장을 돕는다. 이런 생체적 신비감까지 지닌 녹용은 어찌 보면 귀중한 자연의 산물이다.

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A Study on the Cooling and Heating Load according to a Recent Seasonality Change (최근 전력수요의 계절성 변화에 따른 냉.난방 부하 연구)

  • Park, Jong-In;Kim, Kwang-In
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.664-665
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    • 2011
  • 최근 겨울철과 여름철에 다양한 냉난방기기의 보급이 급증하여 최대전력에 대한 기온의 영향이 상당히 커지고 있다. 이에 따라 기온의 영향으로 인한 계절성이 급등하여 전력수요 예측결과의 불확실성을 증폭시키고 있다. 그러나 아직까지는 이러한 냉방 및 난방부하의 급증에 따른 계절성 변화에 대한 체계적인 분석 방법이 정형화되어 있지 못하다. 따라서 본 연구에서는 누적기온반응함수, 기온분포함수, 공적분 및 오차수정모형 등을 바탕으로 엄격한 통계적 검증을 거쳐 냉난방부하 추정 방법을 연구하였고, 아울러 관련 결과를 제시함으로써 향후의 전력수급에 안정적 기반을 제공코자 한다.

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