• Title/Summary/Keyword: annual trend

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

  • Cho, Kyou-Seung;Kang, Won-Koo;Lee, Youn-Seob
    • Proceedings of the KIEE Conference
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    • 1991.07a
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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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Long-term Trends of Visibility in Seoul and Chunchon (서울과 춘천의 장기간 시정 변화경향)

  • 이종범;김용국;백복행
    • Journal of Korean Society for Atmospheric Environment
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    • v.12 no.4
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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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The Suggested Methods for Electric Load Flattening (전력(電力) 부하평준화(負荷平準化) 방안(方案))

  • Jo, Gyu-Seung;Yoon, Kap-Koo
    • Proceedings of the KIEE Conference
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    • 1985.07a
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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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Comparison of Chukwooki and Modern data Using Annual Maximum Rainfall Event Series (연최대 호우사상 계열을 이용한 측우기자료 및 현대자료의 비교)

  • Park, Minkyu;Yoo, Chulsang;Kim, Hyeon Jun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.2B
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    • pp.137-147
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    • 2010
  • In this study, Chukwooki and modern data were compared using annual maximum rainfall event series. Annual maximum series for specified rainfall duration in modern frequency analysis can not be constructed from Chukwooki data, so the concept of independent rainfall event is introduced to compare Chukwooki and modern data. Annual maximum rainfall event is determined by applying the bivariate exponential distribution and the parameters estimated annually are selected. The results using the annual parameter show that the hydrological meaning of the parameters is related to the variation of annual total rainfall amounts. For the whole independent rainfall events, the total rainfall and the rainfall intensity of Chukwooki data are greater than those of modern data, and rainfall duration of the two periods is similar. However modern annual maximum rainfall events show different characteristics that rainfall duration is much longer, rainfall intensity is similar and the total rainfall is greater than those of Chukwooki period. The increasing trend of rainfall duration and total rainfall of the modern annual rainfall events may be regarded as the one of components of the long-term cycle.

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

  • Uranchimeg, Sumiya;Kim, Yong-Tak;Kwon, Hyun-Han;Hwang, Kyu-Nam
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.27 no.2
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    • pp.94-104
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    • 2015
  • Population and urban development along the coast is growing in South Korea, and particularly sea level rise is likely to increase the vulnerability of coastal areas. This study aims to investigate the sea level rise through Mann-Kendall(MK) test, ordinary linear regression(OR) and quantile regression analysis(QRA) with sea level data at the 20 tide stations along the coast of Korean Peninsula. First, statistically significant long-term trends were analysed using a non-parametric MK test and the test indicated statistically significant trends for 18 and 10 stations at the 5% significance level in the annual mean value of sea level and the annual maximum value of sea level, respectively. The QRA method showed better performance in terms of characterizing the degree of trend. QRA showed that an average annual rise in mean sea level is about 1-6 mm/year, and an average rise in maximum sea level is about 1-20 mm. It was found that upward convergent and upward divergent were a representative change given the nine-category distributional changes. We expect that in future work we will address nonstationarities with respect to sea level that were identified above, and develop a nonstationary frequency analysis with climate change scenarios.

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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    • v.17 no.5
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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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    • v.17 no.3
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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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    • v.17 no.1
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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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    • v.26 no.11
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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.

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

  • Baek, Hye-Young;Kim, Kook-Sun
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2006.11a
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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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