• 제목/요약/키워드: Seasonal dynamic

검색결과 97건 처리시간 0.028초

Statistical analysis of SC-associated geosynchronous magnetic field perturbations

  • 김관혁;박종선;이동훈;진호
    • 천문학회보
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    • 제37권1호
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    • pp.91.2-91.2
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    • 2012
  • Kokubun (1983) reported the local time variation of normalized amplitude of sudden commencement (SC) with a strong day-night asymmetry at geosynchronous orbit with 81 SC events. Further careful inspection of Kokubun's local time distribution reveals that the normalized SC amplitudes in the prenoon sector are larger than those in the postnoon sector. That is, there is a morning-afternoon asymmetry in the normalized SC amplitudes. Until now, however, there are no studies on this SC-associated morning-afternoon asymmetry at geosynchronous orbit. Motivated by this previous observation, we investigate a large data set (422 SC events in total) of geosynchronous SC observations and confirm that the geosynchronous SC amplitudes is larger in the morning sector than in the afternoon sector. This morning-asymmetry is probably caused by the enhancement of partial ring current, which is located in the premidnight sector, due to solar wind dynamic pressure increase. We also examine the latitudinal and seasonal variations of the normalized SC amplitude. We find that the SC-associated geosynchronous magnetic field perturbations are dependent on the magnetic latitude and season of the year. This may be due to the location of the magnetopause and cross-tail currents enhanced during SC interval with respect to geosynchronous spacecraft position.

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Hourly Steel Industry Energy Consumption Prediction Using Machine Learning Algorithms

  • Sathishkumar, VE;Lee, Myeong-Bae;Lim, Jong-Hyun;Shin, Chang-Sun;Park, Chang-Woo;Cho, Yong Yun
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2019년도 추계학술발표대회
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    • pp.585-588
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    • 2019
  • Predictions of Energy Consumption for Industries gain an important place in energy management and control system, as there are dynamic and seasonal changes in the demand and supply of energy. This paper presents and discusses the predictive models for energy consumption of the steel industry. Data used includes lagging and leading current reactive power, lagging and leading current power factor, carbon dioxide (tCO2) emission and load type. In the test set, four statistical models are trained and evaluated: (a) Linear regression (LR), (b) Support Vector Machine with radial kernel (SVM RBF), (c) Gradient Boosting Machine (GBM), (d) random forest (RF). Root Mean Squared Error (RMSE), Mean Absolute Error (MAE) and Mean Absolute Percentage Error (MAPE) are used to measure the prediction efficiency of regression designs. When using all the predictors, the best model RF can provide RMSE value 7.33 in the test set.

전산유체해석과 실측을 이용한 도심내 미기후 특성에 대한 연구 (A Study on the Characteristic Micro-Climate in the City using Computerized Fluid Analysis and Actual Measurement)

  • 유장열;박민우
    • 한국공간구조학회논문집
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    • 제23권1호
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    • pp.35-43
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    • 2023
  • Microclimate analysis was conducted through actual measurement according to land use status in urban, and CFD analysis was conducted to analyze and predict the microclimate characteristics of urban, and compared and analyzed with the actual measurement results. It was measured in high-rise areas and parks, and the temperature of the park area was 0.4 to 0.6℃ lower, and the relative humidity was 1.0 to 3.0% higher. The correlation coefficient was obtained by comparing the results of the computational fluid analysis with the results of the computational fluid analysis at the actual location located within the CFD analysis area for validation. The seasonal correlation coefficients are all higher than 0.8, so it is judged that they can be applied to microclimate analysis in urban area. The computational fluid analysis was divided into three areas (low-rise, low and high-rise, and high-rise) centered on the A2 point. On average, the low-rise area was 0.1 to 0.4% higher than the high-rise area. In the low and high-rise area and high-rise area, the pith of buildings are wide, so the airflow is smooth, so it is judged that the temperature is relatively low.

중성자 수분측정기를 이용한 고속도로 포장의 계절별 함수량 변화 측정에 관한 연구 (A Study on Seasonal Variation of Water Content under Highway Asphalt Pavements Using Neutron Moisture Meter)

  • 송관철;이상모;류순호;류관식;박무언
    • 한국농림기상학회지
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    • 제2권4호
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    • pp.156-166
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    • 2000
  • 포장의 토양 역학적 거동 및 내구성에 영향을 주는 노상토의 함수량을 측정함으로써 국내 고속도로 포장의 계절별 함수량의 변동상황에 관한 자료를 제공하고, 노상토의 계절별 함수량 변화와 토양인자 및 기상인자들과의 상관 관계를 밝히려고 연구를 수행하였다 포장의 함수량에 영향을 줄 수 있는 인자 중 지형, 지질과 토양, 성토 혹은 절토 여부 등의 인자와, 기상자료를 얻을 수 있는 기상 관측소와의 거리를 고려하여 경부, 영동 및 호남고속도로의 8개 측정지점을 선정하여 중성자 수분 측정기로 1992년 8월부터 1993년 9월까지 2주마다 함수량을 측정하였다. 50 cm 이상 깊이의 토양단면 상층부의 함수량($\theta$$_{w}$)은 호남고속도로의 이서 지역을 제외하고는 7~12% 범위로 측정지점간에 차이가 크지 않았다. 그러나 60또는 70 cm 이하 깊이의 하층부의 함수량은 측정지점에 따른 차이가 매우 컸다. 원지형(신갈) 또는 절토지(추풍령)에서의 함수량 연중 변화폭은 약 4%정도로서 성토지(신갈, 추풍령 이외의 6개 지역) 에서의 연중 변화폭인 약 2%보다 약간 큰 경향이었다. 함수량 측정지점의 계절별 함수량 변화폭은 토양 전층을 통하여 1~4%로 매우 작았다. 고속도로 포장의 깊이별 함수량은 점토, 미사 및 모래함량 등과 같은 토양특성과 통계적으로 유의성이 높은 정의 상관관계가 있었으나, 강수량, 상대습도, 평균기온 및 풍속 등과 같은 기상인자와는 상관관계가 거의 없었다. 이와 같은 결과는 지역에 따른 함수량 차이가 지형이나 기상조건과 같은 요인에 의한 차이보다 큰 경향을 보이고 있었는데, 이는 주로 노상토로 사용한 토양의 특성에 기인한 것으로 생각된다.

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패션제품의 동태적 구매반응함수에 관한 연구 (A Study on the Dynamic Purchase Response Function for Fashion Goods)

  • 이민호;곽영식;황선진
    • 복식
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    • 제64권2호
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    • pp.35-49
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    • 2014
  • In cases of fashion businesses operating by consignment, base estimate on quantity of sales is the most essential part of merchandising. This study classified factors influential to sales into factors with systematic influence and factors with unsystematic influence. In order to find out influence of each factor on sales, non-linear regression was used with SPSS package on the basis of actual data on sales for 5 years for sport shoes brand. Major findings of this study are as follows. First, price level had significant negative(-) influence on sales. Second, price expectation effects had significant negative(-) influence on sales. Third, competitor's price effect showed significant negative(-) value. Fourth, day-of-the-week effect showed significant positive(+) effect. The theoretical marketing implications of this study are as follows. First, study on price leads to expansion of the researches from apparels to sport shoes. Field of study on price was enlarged through expansion of variable of study from price level and price expectation effect to promotion, day-of-the-week effect and rainfall effect. Second, quantitative scale of day-of-the-week effect was found and it could be confirmed that there was seasonal differences with day-of-the-week effect. Implications of above findings on marketing managers are as follows. First, it was found that an increase in competitiveness of brand power and a decline in absolute value of competitor's price effect can be realized when new product groups are developed to meet the unsatisfied needs in the market. Second, it was possible to find out the parameters scales of the price response function, making it possible to estimate sales for the next season, and in turn realize increase in rate of sales and profit rate. This research is based on the dynamic price response function, which is rare to find in the apparel business and it academic significance due to its expanding response model which was focused on price in conventional researches to non-systematic variables.

소나무와 굴참나무 임분의 토양 환경요인과 토양 이산화탄소 방출의 계절적 변화 (Seasonal Variations of Soil CO2 Efflux Rates and Soil Environmental Factors in Pinus densiflora and Quercus variabilis Stands)

  • 백경원;조창규;김춘식
    • 한국농림기상학회지
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    • 제18권3호
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    • pp.120-126
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    • 2016
  • 본 연구는 유사한 입지에서 생육한 소나무와 굴참나무 임분의 토양 이산화탄소($CO_2$)와 이들 방출에 영향을 미치는 환경요인인 토양 온도, 토양 수분, 토양 pH, 전기전도도, 토양 유기탄소 농도 등을 2015년 3월부터 2016년 2월까지 1년 동안 조사하였다. 토양 $CO_2$ 방출량의 월별 변화는 두 임분 사이에 차이가 있어 하절기인 6월과 7월의 경우, 굴참나무 임분이 소나무 임분에 비해 유의적으로 높았으나, 타 계절은 차이가 없었다. 연 평균 토양 $CO_2$ 방출량의 경우, 굴참나무 임분이 $2.27{\pm}0.22{\mu}mol\;m^{-2}s^{-1}$로 소나무 임분의 $1.63{\pm}0.12{\mu}mol\;m^{-2}s^{-1}$ 에 비해 높게 나타났으며, 연 평균 토양 온도와 토양 수분함량도 굴참나무 임분이 소나무 임분에 비해 높았다. 토양 환경요인 중 토양 온도와 토양 $CO_2$ 방출량은 지수함수 관계(P<0.05)가 있었으며, $Q_{10}$ 값의 경우, 굴참나무 임분이 3.35로 소나무 임분 2.72에 비해 높아 토양 온도 상승 시, 굴참나무 임분의 토양 $CO_2$ 방출량이 소나무 임분에 비해 더 크게 증가하는 것으로 나타났다.

Seasonal Changes in Biochemical Components of the Adductor Muscle, Digestive Diverticula and the Ovary in Female Chlamys farreri in Relation to the Ovarian Developmental Phases

  • Kim, Hyun-Jin;Chung, Ee-Yung;Park, Ki-Yeol;Kim, Eun-Jong
    • 한국발생생물학회:학술대회논문집
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    • 한국발생생물학회 2005년도 제20차 학술대회 논문집
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    • pp.51-51
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    • 2005
  • We inestigated the reproductive cycle with ovarian development of Chlamys farreri by histological observations, and seasonal changes in biochemical components of the adductor muscle, digestive diverticula and ovary were studied by biochemical analysis. The reproductive cycle of this species can be classified into five successive stages: early active stage (January to March), late active stage (March to April), ripe stage (April to August), partially spawned stage (June to August) and spent/inactive stage (August to January). According to ANOVA test, there were significant differences (p<0.05) in total protein, total lipid and glycogen contents among months for all of the adductor muscle, digestive diverticula and ovary. Total protein contents in ovary and digestive diverticula showed significant changes(ANOVA, p<0.05) during the study period, while that in the adductor muscle did not. Total protein content was highest in the adductor muscle, followed by ovary, and lowest in digestive diverticula. There was no correlation in total protein content between the adductor muscle and digestive diverticula (p=0.220). But strong positive correlation was found between adductor muscle and ovary (r=0.450, p=0.013). ANOVA showed that there were significant differences in total lipid and glycogen contents among months for all of the adductor muscle, ovary, and digestive diverticula (p<0.05). The monthly changes in total lipid content were highly variable in ovary and digestive gland. High contents of total lipid were foung during April and May-June in ovary, while March and June-July in digestive diverticula. There was a strong negative correlation in total lipid content between ovary and digestive diverticula (r=- 0.397, p=0.030). Unlike total protein of total lipid, glycogen content in the adductor muscle was most dynamic. It showed more than 36-fold changes in the adductor muscle (at most 3-fold change in ovary) during the study period. Glycogen content was higher during May-July in the adductor muscle, While it was higher in March and august in digestive diverticula. There was a strong negative correlation in glycogen content between the adductor muscle and digestive diverticula (r=-0.584, p=0.001).

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서울과 경기지역의 주가성 쥐에 기생하는 진드기군집의 구조와 동태에 관하여 (The Community Structure and Dynamic of Parasitic Mites on House Rats)

  • Kim Meung Hai;Hai Poong Lee
    • The Korean Journal of Ecology
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    • 제12권2호
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    • pp.123-132
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    • 1989
  • 주가성 쥐의 진드기 류에 대한 기생률은 4척조사지역 모두 2, 3월에는 낮고 6월부터 8월까지는 최고 기생률을 보였으며 채집된 진드기류는 3아목 5과 12속 21종이었고 숙주별로는 집쥐에서 19종, 곰쥐에서 11종이 채집되었다. 숙주선택성은 집쥐에서 10종으로 나타났으며 T-mites는 서울과 양수리지역이 다른 조사지역보다 많이 곳현했으며 L. palpale가 우점종으로 나타났다. 종다양도와 균등도와 지역별 비교는 양수리지역의 종구성이 다양하고 균등도는 인천지역이 가장 높았으며 계절별로 우점도를 보면 서울지역은 5월에, 성남지역은 3월에, 인천지역과 양수리지역은 년중 높게 나타났다. 지역별 유사도지수는 양수리와 서울지역이 0.8333으로 가장 높았다. 서울과 성남지역은 봄과 여름에, 인천지역은 여름과 가을에, 양수리지역은 겨울철에 다른 조사지역보다 진드리류가 많이 나타났으며 인천지역은 다른 3척 조사지역과는 달리 집쥐에서보다 곰쥐에서 더 많은 충체를 보유하고 있었다.

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비단가리비, Chlamys farreri의 난소 발달단계에 따른 폐각근, 난소 및 소화맹낭의 생화학적 성분의 계절적 변화 (Seasonal Changes in Biochemical Components of the Adductor Muscle, Digestive Diverticula and the Ovary in Chlamys farreri in Relation to the Ovarian Developmental Phases)

  • 정의영;구재근;박기열;이창훈
    • 한국패류학회지
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    • 제21권1호
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    • pp.71-80
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    • 2005
  • We investigated the reproductive cycle with ovarian development of Chlamys farreri by histological observations, and seasonal changes in biochemical components of the adductor muscle, digestive diverticula and ovary were studied by biochemical analysis. The reproductive cycle of this species can be classified into five successive stages: early active stage (January to March), late active stage (March to April), ripe stage (April to August), partially spawned stage (June to August) and spent/inactive stage (August to January). According to ANOVA test, there were significant differences (p < 0.05) in total protein, total lipid and glycogen contents among months for all of the adductor muscle, digestive diverticula and ovary. Total protein contents in ovary and digestive diverticula showed significant changes (ANOVA, p < 0.05) during the study period, while that in the adductor muscle did not. Total protein content was highest in the adductor muscle, followed by ovary, and lowest in digestive diverticula. There was no correlation in total protein content between the adductor muscle and digestive diverticula (p = 0.220). But strong positive correlation was found between adductor muscle and ovary (r = 0.450, p = 0.013). ANOVA showed that there were significant differences in total lipid and glycogen contents among months for all of the adductor muscle, ovary, and digestive diverticula (p < 0.05). The monthly changes in total lipid content were highly variable in ovary and digestive gland. High contents of total lipid were found during April and May-June in ovary, while March and June-July in digestive diverticula. There was a strong negative correlation in total lipid content between ovary and digestive diverticula (r = -0.397, p = 0.030). Unlike total protein or total lipid, glycogen content in the adductor muscle was most dynamic. It showed more than 36-fold changes in the adductor muscle (at most 3-fold change in ovary) during the study period. Glycogen content was higher during May-July in the adductor muscle, while it was higher in March and August in digestive diverticula. There was a strong negative correlation in glycogen content between the adductor muscle and digestive diverticula (r = -0.584, p = 0.001).

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마산-진해만의 수질 부영양화 및 계절 변동 (Eutrophication and Seasonal Variation of Water Quality in Masan-Jinhae Bay)

  • 조경제;최만영;곽승국;임성호;김대윤;박종규;김영의
    • 한국해양학회지:바다
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    • 제3권4호
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    • pp.193-202
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    • 1998
  • 마산-진해만에서 1996년 1월부터 1997년 8월까지 영양염류, 용존산소, 해수 투명도 등 수질의 부영양화 요인과 식물플랑크톤 생물량의 수직변동, 공간분포 및 계절변동 등을 조사하였다. 식물플랑크톤은 4월부터 10월까지 번무하였으며, 이 기간에는 편모조류가 단독으로 발생하거나 여러 종이 혼합 발생하는 등 매우 역동적인 양상을 보였다. 식물플랑크톤 대발생 시기에는 염분이 감소하였고, 편모조류의 번무로 수색이 변하거나 물의 투명도가 떨어졌다. 여름에 하층은 빈산소상태였으나 상층은 산소의 과포화상태로서 상 하층에 용존산소의 성층화가 형성되었고, 그 구배가 컸다. 반면 겨울에는 영양염류의 수직 분포가 균일하였고, 마산 내만에서 진해 외만에 걸쳐 영양염류의 수평적 구배가 발달하였다. 마산-진해만 수질은 여름에는 저질 퇴적층에서 용출되는 영양염류의 영향을 많이 받았으나, 겨울에는 마산시와 창원시 등 주변 집수역에서 유입되는 오 폐수의 영향을 주로 받는 것으로 추정되었다. 과거 마산-친해만 일원의 수질 분석 자료를 수집하여 마산만 돌섬과 부도 사이의 수질을 연 평균값으로 표준화시킨 결과, COD와 $PO_4$가 비교 가능하였다. 1970년부터 1990년까지 마산만에서 COD와 $PO_4$ 농도는 점진적으로 증가하였으나, 1991년 이후 다소 둔화되거나 감소한 것으로 나타났다. 1991년부터 1994년까지 마산 내만에서 행한 저질 퇴적층의 준설이 이 지역의 수질 악화를 다소 완화시킨 것으로 추정된다.

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