• 제목/요약/키워드: Seasonal effect

검색결과 693건 처리시간 0.034초

몬순지역 대형댐(소양호)에서 동물플랑크톤 군집의 계절천이 (Seasonal Succession of Zooplankton Community in a Large Reservoir of Summer Monsoon Region (Lake Soyang))

  • 김문숙;김범철;전만식
    • 생태와환경
    • /
    • 제52권1호
    • /
    • pp.40-49
    • /
    • 2019
  • 본 연구는 몬순지역의 대형호인 소양호를 대상으로 동물플랑크톤의 종 조성과 생물량을 조사하였으며, 군집의 계절천이를 알아보고자 하였다. 또한, PEG 모델과 몬순지역에서 다른 호수와의 동물플랑크톤 계절천이를 비교하여 고찰하였다. 조사기간 동안 소양호 유역의 강수량은 $705{\sim}1,779mm\;yr^{-1}$의 큰 변동을 보였으며, 70% 이상이 6~9월에 집중되는 것으로 나타났다. 소양호의 수질은 연도별 변화보다 계절적 변화가 뚜렷하게 나타났으며, 몬순기후로 인한 여름철 홍수기 탁수유입이 가장 중요한 환경요인으로 작용하였다. 소양호에서 동물플랑크톤 종 조성의 계절천이는 연도별로 차이는 있지만, 매년 두 시기에 거쳐 뚜렷한 경향을 보였다. 봄 시기에는 소형 동물플랑크톤이 우점하였으며, 여름과 가을 시기에는 크기가 큰 지각류와 요각류가 우점하였다. 동물플랑크톤의 생물량은 집중강우 이후 9월에 최대를 보였으며, Chl. a 농도와 유사한 계절변동을 보였다(r=0.45). 소양호에서 동물플랑크톤의 생물량 증가는 강우 시 유입된 영양염과 유기물에 의한 미생물, 식물플랑크톤 등 먹이유용성 증가에 따른 microbial loop와 bottom-up 효과로 판단된다. 결과적으로, 몬순지역의 대형호인 소양호 동물플랑크톤은 종별 계절천이는 PEG 모델을 따랐지만, 생물량의 계절천이는 온대호수뿐만 아니라 몬순지역의 호수와도 차이를 보였다. 이는 유역에서 유입된 다량의 유기물 등과 함께 소양호의 수심, 체류시간 등 수리학적 특성에 따른 영향으로 판단된다.

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.

하천호안공법의 시각적 선호도 - 광양시 동천을 사례로 - (Visual Preference of the Methods for River Embankment - The Case of Dongchon in Gwangyang -)

  • 이상석
    • 한국조경학회지
    • /
    • 제34권3호
    • /
    • pp.12-22
    • /
    • 2006
  • The purpose of this study is to evaluate visual preferences of the methods for river embankment based on seasonal changes and to reveal the relationship between visual preference and effective factors, which are the physical and esthetic elements inside the river. For this research seven river embankment methods including concrete block, concrete wall, gabion, and vegetated concrete block were selected in Dongchon of Gwangyang. Twenty-eight pictures by the four pictures of each embankment method based on seasonal changes, the winter and summer of the first and second years after construction were used for a photo-questionnaire by 49 participants. In the analysis of the relationship between visual preference and effective factors, the independent variables included eight factors: form of the material, harmony with the surroundings, the cleanness of river floor, the green area of embankment methods, the water area in river floor, the stone and sand area in river floor, the planting area in river floor, and the area of embankment itself. The result of this study are as follows. First, visual preference in summer was higher than in winter, and the summer landscape of the second you scored the highest value for visual preference. Second, similarly to the way the vegetated concrete block produced a green effect, cobblestone and gabion embankments made of natural materials scored higher than others, whereas the concrete retaining wall scored the lowest of all methods because of it's artificiality. Third, the seven independent variables, except form of the material, are proved statistically significant at the 5% level. The water area in river floor, harmony with the surroundings, the planting area in river floor, and the cleanness of the river floor were revealed as more effective factors influencing visual preference. The research results suggest that the riverscape has to be controlled in terms of seasonal change and embankment methods. Natural materials and green effects in embankment methods are more important for increasing landscape preference, and the landscape factors inside a river should also be considered important variables. It is recommended that advanced study on other factors affecting visual preference of the riverscape be carried out to support this research.

초인지 학습전략이 초등학생의 계절의 변화 개념 형성과 자기 효능감에 미치는 효과 (Effects of Metacognitive Learning Strategy on Elementary School Students' Conception Acquisition of Seasonal Change and Self-efficacy)

  • 정홍식;한영욱
    • 한국초등과학교육학회지:초등과학교육
    • /
    • 제25권1호
    • /
    • pp.39-50
    • /
    • 2006
  • The purpose of this study was to investigate the effect of metacognitive strategy on conceptual acquisition ofvseasonal change and self-efficacy when it was applied to 6th grade elementary students. This study consists of 2 classes, 76 students in the 6th grade of elementary school, which were divided into the experimental group (38) and the control group (38). First, a pre-test was administrated to check students' levels of metacognitive self-regulation and self-efficacy prior to getting planned lessons and then an instruction program was developed based upon the metacognitive instruction model and students' conception. The control group was exposed to traditional methods mainly using the textbook and teacher's guide book. The experimental group employed a metacognitive learning strategy program and activities with metacognitive questionnaires. After the planned lessons, the students were tested with post-tests about the conception of seasonal change and self-efficacy. One month later the students were tested again with another test to determine the continuation effect. The results were as follows: First, the group that used metacognitive conceptual change instruction did better in forming and continuing to maintain the scientific seasonal change conceptions compared to the control group. Second, the high and intermediate group taught by metacognitive conceptual change instruction was higher in the level of self-regulation than the control group. However, it was not verified in the low group. Third, the group which used metacognitive conceptual change instruction showed a higher level of self-efficacy than the control group did.

  • PDF

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

  • 채제민;정만복;최신주;박신애;이나영;김원태;서강문
    • 한국임상수의학회지
    • /
    • 제30권2호
    • /
    • pp.95-99
    • /
    • 2013
  • 본 연구는 정상개에서의 계절에 따른 안압의 변화를 평가하기 위해서 실시되었다. 총 474마리의 안질환이 없는 삽살개의 양안에 대해서 편평안압계(Tonopen$^{(R)}$ XL)를 이용해서 안압을 측정하였다. 측정된 결과를 바탕으로, 안압에 영향을 줄 것으로 예상되는 요소의 유의성과, 각 요소의 군내 차이를 통게적 방법을 통하여 검증을 실시 하였다. 전체 삽살개의 평균 안압 및 표준 편차는 $19.1{\pm}3.7$ mmHg (범위: 8 to 28 mmHg) 이었다. 계절적 요소에서만 안압 변화에 대한 유의성이 검증 되었고(P < 0.001), 그 외 나이, 성별, 모색과 관련된 유의성은 확인되지 않았다. 겨울에 측정된 평균 안압 수치($20.4{\pm}3.4$ mmHg)와 여름에 측정된 평균 안압 수치($17.1{\pm}3.6$ mmHg) 는 다른 계절의 평균 안압에 비하여서 신뢰구간 내로 각각 높게 그리고 낮게 측정 되었다. 이상의 결과를 바탕으로 계절적 변화는 정상 개의 안압에 영향을 줄 것으로 판단되며, 본 연구는 후속되는 수의 안과 연구와 수의 안과 임상에 유용한 자료가 될 것으로 사료된다.

기온과 특수일 효과를 고려하여 시계열 모형을 활용한 일별 최대 전력 수요 예측 연구 (Forecasting daily peak load by time series model with temperature and special days effect)

  • 이진영;김삼용
    • 응용통계연구
    • /
    • 제32권1호
    • /
    • pp.161-171
    • /
    • 2019
  • 일별 최대전력 수요 예측은 국가의 전력 수급운영에 중요한 과제로서 과거부터 다양한 방법들이 끊임없이 연구되어 왔다. 일별 최대전력 수요를 정확히 예측함으로써 발전설비에 대한 일일 운용계획을 작성하고 효율적인 설비 운용을 통해 불필요한 에너지 자원의 소비를 감소하는데 기여할 수 있으며 여름 겨울철 냉난방수요로 인해 발생하는 전력소비 과다로 인한 전력예비율 감소 문제 등에 선제적으로 대비할 수 있는 장점을 가진다. 이러한 일별 최대전력수요 예측을 위하여 본 논문에서는 Seasonal ARIMA, TBATS, Seasonal Reg-ARIMA, NNETAR 모형에 평일, 주말, 특수일에 대한 효과와 온도에 대한 영향을 함께 고려하여 다음날의 일별 최대전력을 예측하는 모형을 연구하였다. 본 논문을 통한 모형들의 예측 성능 평가 결과 요일, 온도를 고려할 수 있는 Seasonal Reg-ARIMA 모형과 NNETAR 모형이 이를 고려할 수 없는 다른 시계열 모형보다 우수한 예측 성능을 나타내었고 그 중 인공신경망을 활용한 NNETAR 모형의 예측 성능이 가장 우수하였다.

Effect of seasonal changes on nutritional status and biochemical parameters in Turkish older adults

  • Ersoy, Nesli;Tasci, Ilker;Ozgurtas, Taner;Salih, Bekir;Doruk, Huseyin;Rakicioglu, Neslisah
    • Nutrition Research and Practice
    • /
    • 제12권4호
    • /
    • pp.315-323
    • /
    • 2018
  • BACKGROUND/OBJECTIVES: Available data suggest that seasonal changes may influence the nutritional status and overall health of elderly individuals. Therefore, this study was conducted to investigate the effects of seasonal changes and related factors on energy and nutrient intake of older adults. SUBJECTS/METHODS: Individuals aged 65 years or over were prospectively enrolled in this single-center study (male: 11, female: 20). Data were collected between May 2013 and February 2014 during winter, spring, summer and autumn. Food consumption and biochemical parameters were taken during each season to assess the seasonal nutrition status of the elderly. Upon analysis of biochemical parameters (retinol, vitamin D and vitamin C), an high-performance liquid chromatography device was utilized whereas an Immulite 2000 device was utilized during analysis of serum folic acid and parathyroid hormone. RESULTS: Fruit, fat, egg and bread consumption varied seasonally in males and females (P < 0.05). During winter, daily energy intake was found to be greater than in other seasons in males (557 kcal) and females (330 kcal) (P < 0.05). Additionally, carbohydrates, vegetable protein, n-3 fatty acid and sodium intake increased in winter, while the n-6/n-3 ratio increased in summer among males (P < 0.05). Dietary fiber and sodium intake in winter, vitamin C, iron and zinc intake in spring, and cholesterol, retinol, vitamin D and niacin intake in autumn were found to be higher in females when compared to other seasons (P < 0.05). Serum parathyroid hormone level was higher in winter, and vitamin D level was higher in autumn in both genders (P < 0.05). In males, blood folic acid level was higher in winter, while vitamin C level was higher in females, and there was no seasonal variation in retinol concentration (P < 0.05). CONCLUSION: Food consumption and biochemical parameters showed significant seasonal variations in older adults. It is not clear if nutrition plans in older adults will benefit from consideration of seasonal changes in eating habits.

Seasonal and Latitudinal Variations of the F2-Layer during Magnetic Storms

  • Park, Yoon-Kyung;Kwak, Young-Sil;Ahn, Byung-Ho
    • Journal of Astronomy and Space Sciences
    • /
    • 제30권4호
    • /
    • pp.231-239
    • /
    • 2013
  • To identify seasonal and latitudinal variations of F2 layer during magnetic storm, we examine the change of daily averages of foF2 observed at Kokubunji and Hobart during high (2000~2002) and low (2006~2008) solar activity intervals. It is found that geomagnetic activity has a different effect on the ionospheric F2-layer electron density variation for different seasons and different latitudes. We, thus, investigate how the change of geomagnetic activity affects the ionospheric F2-layer electron density with season and latitude. For this purpose, two magnetic storms occurred in equinox (31 March 2001) and solstice (20 November 2003) seasons are selected. Then we investigate foF2, which are observed at Kokubunji, Townsville, Brisbane, Canberra and Hobart, Dst index, Ap index, and AE index for the two magnetic storm periods. These observatories have similar geomagnetic longitude, but have different latitude. Furthermore, we investigate the relation between the foF2 and the [O]/[$N_2$] ratio and TEC variations during 19-22 November 2003 magnetic storm period. As a result, we find that the latitudinal variations of [O]/[$N_2$] ratio and TEC are closely related with the latitudinal variation of foF2. Therefore, we conclude that the seasonal and latitudinal variations of foF2 during magnetic storm are caused by the seasonal and latitudinal variations of mean meridional circulation of the thermosphere, particularly upwelling and downwelling of neutral atmosphere during magnetic storm.

국내 응급 센터의 뱀교상 환자의 특징: 국가응급의료정보망 (Epidemiology of patients with snake bite or envenomation in emergency department: NEDIS (National Emergency Department Information System))

  • 이세록;전우찬
    • 대한임상독성학회지
    • /
    • 제20권2호
    • /
    • pp.45-50
    • /
    • 2022
  • Purpose: This study utilizes the NEDIS (National Emergency Department Information System) database to suggest a predictive model for snakebite and envenomation in Korea by analyzing the geographical distribution and seasonal variation of snakebite patients visiting the ER. Methods: This was a retrospective study on snakebite patients visiting the ER using the NEDIS database from January 2014 to December 2019. The subjects include patients with the KCD (Korea Standard Classification of Disease) disease code T63.0 (Toxic effect of contact with snake venom). Geographical location, patient gender, patient age, date of ER visit, treatment during the ER stay, and disposition were recorded to analyze the geographical distribution and seasonal variation of snakebite patients in Korea. Results: A total of 12,521 patients were evaluated in this study (7,170 males, 54.9%; 5,351 females, 40.9%). The average age was 58.5±17.5 years. In all, 7,644 patients were admitted with an average admission time of 5.04±4.7 days, and 2 patients expired while admitted. The geographical distribution was Gyeongsang 3,370 (26.9%), Cheonra 2,692 (21.5%), Chungcheong 2,667 (21.3%), Seoul Capital area 1,999 (16.0%), Kangwon 1,457 (11.6%), and Jeju 336 (2.7%). The seasonal variation showed insignificant incidences in winter and higher severity in spring and summer than in fall: winter 27 (0.2%), spring 2,268 (18.1%), summer 6,847 (54.7%), and fall 3,380 (27.0%). Conclusion: Patients presenting with snakebites and envenomation in the emergency room were most common in the Gyeongsang area and during summer. The simple seasonal model predicted that 436 snakebites and 438 envenomation cases occurred in July and August. The results of this study can be applied to suitably distribute and stock antivenom. Appropriate policies can be formed to care for snakebite patients in Korea.