• 제목/요약/키워드: annual trend

검색결과 698건 처리시간 0.025초

하계전력수급 안정을 위한 부하관리 대책 (A Study on the Load Management for the Stability of Power Supply in summer)

  • 조규승;강원구;이윤섭
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1991년도 하계학술대회 논문집
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    • pp.17-18
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    • 1991
  • In electric Industry, the improvement of load factor by flattening load has been considered to be more important than any other tasks and has received wide concern and interest. Especially while annual peak load had occurred early evening in winter during past decades, but we found the trend has changed so that annual peak load occurred during the daytime in summer since 1981. In this paper we introduce various method for the load management.

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서울과 춘천의 장기간 시정 변화경향 (Long-term Trends of Visibility in Seoul and Chunchon)

  • 이종범;김용국;백복행
    • 한국대기환경학회지
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    • 제12권4호
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    • pp.473-478
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    • 1996
  • Using data observed from 1966 to 1994, long-term trends of visibility at 15:00 in Seoul and Chunchon were analyzed. Annual average visibility in Seoul has been decreased continuously. In particular, annual number of days for visibility more than 15km was remarkably reduced since 1980. Also, the trend of the visibility in Chunchon was similar to that of Seoul. But the variations were small to compare with Seoul. Long-term trends of relative humidity (RH) and specific humidity (q) at 15:00 in Seoul have been slightly decreased. Cumulative frequency distributions of visibility for ranges of RH (0 $\sim 50%, 50 \sim 60%, 60 \sim 70%, 70 \sim 80%, 80 \sim 90%, 90 \sim 100%$) at 15:00 in Seoul and Chunchon were generally decreased during the second period (1984 $\sim$ 1994) as compared with the first period (1973 $\sim$ 1983), except for the range of 90 to 100% RH. Despite of decreasing phenomena of RH, characteristics of urban climates in Seoul, visibility degraded due to an increase of air pollution.

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전력(電力) 부하평준화(負荷平準化) 방안(方案) (The Suggested Methods for Electric Load Flattening)

  • 조규승;윤갑구
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1985년도 하계학술회의논문집
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    • pp.144-147
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    • 1985
  • In electricity industry, the improvement of load factor by flattening of load has been considered to be more important than any other tasks and has received wide concern and interest. Especially while annual peak load had occured early evening in winter during past decades, but we found the trend has changed so that annual peak load occured during the daytime in summer since1981 The useful practicing methods of this load management ale as follows; 1. Inducing of midnight load by thermal storage water heating 2. Seasonal differential rates. 3. Revising the peak load priceing (Time-of -use) It seems hard to expect that load research can be carried out in a short time, and we all have to exert outselves continuously to provide efficient load management method without wasting resources.

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연최대 호우사상 계열을 이용한 측우기자료 및 현대자료의 비교 (Comparison of Chukwooki and Modern data Using Annual Maximum Rainfall Event Series)

  • 박민규;유철상;김현준
    • 대한토목학회논문집
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    • 제30권2B호
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    • pp.137-147
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    • 2010
  • 본 연구에서는 연최대 호우사상 계열을 이용하여 측우기자료와 현대자료를 비교하였다. 측우기 시강우 자료를 이용하여 현대 빈도해석에서 필요한 특정지속기간의 연최대치 계열을 얻는 것이 불가능하므로 두 관측기간의 비교를 위해 독립호우사상 개념을 이용해 연최대 호우사상 계열을 작성하였다. 연최대호우사상은 이변량지수분포를 이용하여 결정하였으며 모수 추정을 위해 연도별 모수를 이용하는 경우가 보다 적절할 것으로 검토되었다. 이는 연도별 모수를 이용할 경우의 결과가 모수의 경년별 변동성이 연강수량의 변동성과 비교해 의미를 가지기 때문이다. 전체적인 독립호우사상을 비교한다면 현대기록이든 측우기기록이든 강우지속기간에서는 큰 차이가 없지만 현대보다는 측우기 관측기록의 경우가 총강우량과 강우강도가 크게 나타났다. 그러나, 연최대 호우사상의 비교에서는 측우기에 비해 현대의 경우가 강우지속기간이 현격하게 길어지면서 강우강도는 큰 차이가 없게 나타나 총강우량에서 상당한 증가를 보이는 것으로 확인되었다. 또한 이러한 연최대호우사상의 경향성을 살펴본 결과 현대관측기간 동안에는 강우지속기간과 총강우량이 증가하는 경향을 보이고 있지만 측우기 관측기록과 비교시에는 일정한 주기성의 한 부분으로 보는 것이 보다 적절한 것으로 판단되었다.

MK 검정 및 분위회귀분석을 통한 해수면 자료의 경향성 평가에 관한 연구 (A Study on Trend Analysis in Sea Level Data Through MK Test and Quantile Regression Analysis)

  • 오랑치맥 솜야;김용탁;권현한;황규남
    • 한국해안·해양공학회논문집
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    • 제27권2호
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    • pp.94-104
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    • 2015
  • 우리나라의 연안은 도시개발, 인구증가가 지속적으로 나타나고 있으며, 이러한 점에서 해수면 상승으로 인한 연안재해 취약성이 가중될 것으로 전망되고 있다. 본 연구에서는 우리나라 연안의 20개 지역의 조위자료를 바탕으로 Mann-Kendall(MK) 검정, 선형회귀분석(OR), 분위회귀분석(QRA) 등을 이용하여 해수면상승에 대한 분석을 수행하였다. MK 검정결과 연평균조위의 경우 18개 지점에서 경향성이 통계적으로 유의한 것으로 분석되었으며, 연최대치의 경우에도 10개 지점에서 경향성이 통계적으로 유의(p < 0.05)한 것으로 평가되었다. QRA 방법을 이용하여 해수면의 경향성을 분위별로 평가한 결과 기존 회귀분석 방법에 비해 다각적인 경향성 검토가 가능하였다. QRA분석 결과 연평균해수면은 매년 1-6 mm의 범위에서 상승하고 있으며, 연최대해수면의 경우 1-20 mm의 범위에서 증가경향이 나타나고 있음을 확인할 수 있었다. 우리나라의 해수면상승의 경우 대부분 상향수렴 및 상향발산의 형태를 가지는 경향성을 나타내고 있었다. 향후 연구로서 이러한 경향성을 기반으로 연최대해수면 자료에 대한 비정상성빈도해석 절차의 개발 및 적용이 필요할 것으로 판단된다.

Incidence Trend for Non-Hodgkin Lymphoma in the North Tunisian Population, 1998-2009

  • Benhassine, Adel;Khadhra, Hajer Ben;Khiari, Houyem;Hsairi, Mohamed;Elgaaied, Amel Benammar
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권5호
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    • pp.2513-2518
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    • 2016
  • Background: In 2008, non-Hodgkin lymphoma ranked tenth among other malignancies worldwide with an incidence of around 5 cases per 100,000 in both genders. The latest available rates in Tunisia are from 2006. Materials and Methods: This study aimed to provide an update about NHL incidence for 2009 and its trend between 1998 and 2009 as well as a projection until 2024, using data from the Salah Azaiz Institute hospital registry and the Noth Tunisia cancer registry. Results: In 2009, the NHL incidence in the north of Tunisia was 4.03 cases per 100,000, 4.97 for men and 3.10 for women. Diffuse large B-cell lymphoma (DLBCL) accounted for 63.2% of all NHL subtypes. Between 1998 and 2009, the overall trend showed no significant change. When we compared the trend between two periods (1998-2005 and 2005-2009), joinpoint regression showed a significant decrease of NHL incidence in the first period with an annual percentage change (APC) of -6.7% (95% CI:[-11.2%;-2%]), then the incidence significantly increased from 2005 to 2009 with an APC of 30.5% (95% CI: [16.1%; 46.6%]. The analyses of the different subtype trends showed a significant decrease in DLBCL incidence between 1998 and 2000 (APC:-21.5; 95% CI: [-31.4%;-10.2%]) then the incidence significantly increased between 2004 and 2007 (APC: 18.5; 95% CI: [3,6%;35.5%]). Joint point analysis of the age-period-cohort model projection showed a significant increase between 2002 and 2024 with an APC of 4.5% (%95 CI: [1.5%; 7.5%]). The estimated ASR for 2024 was 4.55/100 000 (95% CI: [3.37; 6.15]). Conclusions: This study revealed an overall steady trend in the incidence of NHL in northern Tunisia between 1998 and 2009. Projection showed an increase in the incidence in NHL in both genders which draw the attention to the national and worldwide burden of this malignancy.

Breast Cancer in Iranian Woman: Incidence by Age Group, Morphology and Trends

  • Rafiemanesh, Hosein;Salehiniya, Hamid;Lotfi, Zahra
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권3호
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    • pp.1393-1397
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    • 2016
  • Background: Breast cancer is the most common cancer and the first cause of cancer death in women worldwide, with infiltrating duct carcinoma as the most common morphology. This study aimed to investigate trend of breast cancer incidence by age groups and histological changes in Iranian women between 2003 and 2008. Materials and Methods: This is analytic study, carried out based on re-analysis of the Cancer Registry Center report of health deputy for women's breast cancer in Iran during a 6-year period (2003-2008). Statistical analysis for incidence time trends and morphology change percentage carried out joinpoint regression analysis using the software Joinpoint Regression Program. Results: A total of 36,340 cases were reported for Iranian women in the six years. Analytical trend showed an increasing incidence trend with significant annual percentage change (APC) of 15.2 (CI: 11.6 to 18.8). The lowest and highest significant increased trend were related to age groups of 40 to 44 years and above 85 years, respectively; with APCs of 13.0 and 25.1, respectively. Of total cases, 78.7% of cases were infiltrating duct carcinoma, decreasing from 82.0% in 2003 to 76.6% in 2008, which was significant with an APC equal to -1.76 (CI:-2.7 to -0.8). Conclusions: The incidence trend of breast cancer is rising in Iranian women. The highest incidence was observed in the age groups 45-65 and 80-85. In conclusion, to reduce breast cancer incidence and its burden, preventive and screening programs for breast cancer, especially in young women, are recommended in Iran.

Thyroid Cancer Epidemiology in Iran: a Time Trend Study

  • Safavi, Ali;Azizi, Fereidoun;Jafari, Rozita;Chaibakhsh, Samira;Safavi, Amir Ali
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권1호
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    • pp.407-412
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    • 2016
  • Background: Considering the rising incidence of thyroid cancer worldwide, the aim of our study was to investigate the temporal trends in the incidence of this cancer in a large population of Iranian patients. Materials and Methods: We used the Iran Cancer Data System (ICDS) Registry to assess the thyroid cancer trend from 2004 to 2010 with regard to different genders, age groups, and morphologies. To do this we analyzed the data of 10,913 new cases of thyroid cancer that occurred during these years. Results: The incidence rate (per one year) of thyroid cancer was 2.20 per 100,000 persons between 2004 and 2010 in Iran. Papillary thyroid cancer was the most common histology type, with an annual rate of 0.29 in Iran. The highest rate of prevalence in thyroid cancer was observed at the age of 45 years at the time of diagnosis. We found a female-to-male ratio of 2 in Iran. A significant decrease was detected in the trend of thyroid cancer in children <19y, which was not correlated to the trend of older patients. Conclusions: As expected, the trend of thyroid cancer increased over the 7 years, primarily contributed by papillary thyroid cancer. A rising pattern of incidence was seen in all the age groups except patients aged under 19 years.

Long-term pattern changes of sea surface temperature during summer and winter due to climate change in the Korea Waters

  • In-Seong Han;Joon-Soo Lee;Hae-Kun Jung
    • Fisheries and Aquatic Sciences
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    • 제26권11호
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    • pp.639-648
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    • 2023
  • The sea surface temperature (SST) and ocean heat content in the Korea Waters are gradually increased. Especially the increasing trend of annual mean SST in the Korea Water is higher about 2.6 times than the global mean during past 55 years (1968-2022). Before 2010s, the increasing trend of SST was led by winter season in the Korea Waters. However, this pattern was clearly changed after 2010s. The increasing trend of SST during summer is higher about 3.9 times than during winter after 2010s. We examine the long-term variations of several ocean and climate factors to understand the reasons for the long-term pattern changes of SST between summer and winter in recent. Tsushima warm current was significantly strengthened in summer compare to winter during past 33 years (1986-2018). The long-term patterns of Siberian High and East Asian Winter Monsoon were definitely changed before and after early- or mid-2000s. The intensities of those two climate factors was changed to the increasing trend or weakened decreasing trend from the distinctive decreasing trend. In addition, the extreme weather condition like the heatwave days and cold spell days in the Korea significantly increased since mid- or late-2000s. From these results, we can consider that the occurrences of frequent and intensified marine heatwaves during summer and marine cold spells during winter in the Korea Waters might be related with the long-term pattern change of SST, which should be caused by the long-term change of climate factors and advection heat, in a few decade.

최근 모델하우스에 나타난 주거디자인 경향분석;판교 신도시 모델하우스를 중심으로 (A study on Trend Analysis of Housing Design in the Model House)

  • 백혜영;김국선
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 2006년도 추계학술발표대회 논문집
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    • pp.480-483
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    • 2006
  • The purpose of this study was to examine the spatial composition and characteristics of model houses that have recently opened in Pangyone ara. Site visit and content analysis were adopted in this study. and the studied model houses developed by nine housing were of particular interest. The major findings indicated that convenience and safety through high tech-related features, environmentally friendly features in response to the growing attention of consumers to indoor air quality, aesthetic building facade and its various floor plan, and a wide range of consumers choice for interior finishes and materials. The new trends provides a flexible wall which makes it possible to manipulate the number of rooms according to the family preference.

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