• Title/Summary/Keyword: Annual Trends

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Study on the Long-term Change of Urban Climate in Daegu (대구의 장기적 도시기후 변동에 관한 연구)

  • 김해동
    • Journal of Environmental Science International
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    • v.12 no.7
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    • pp.697-704
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    • 2003
  • Through data analysis using the meteorological data during 40 years(1961∼2000) for 2 stations(Daegu and Chupungnyong), we studied the present condition and long-term trends in urban climatic environments of Daegu. It was found that there was about 1.5$^{\circ}C$ rise in annual mean temperature of Daegu from 1961 to 2000. On the other hand, that of Chupungnyung was not more than 0.4$^{\circ}C$ for the same period. The regional disparity in temperature changes has been caused by the difference of urban effects on climate between two regions. In particular, the urban warming appears more significant in winter season. There was about 3$^{\circ}C$ rise in annual mean daily minimum temperature of winter season(Dec.∼Feb.) in Daegu. As the result, the number of winter days continuously decreased from 115 days(1961) to 75 days(2000). The long-term trends of relative humidity were also studied to exame the effects of urbanization on climate in Daegu. It was found that there was about 7% decrease in relative humidity of Daegu during past 40 years(1961∼2000). On the other side, the decrease of Chupungnyung was not more than 2% for the same period. The long-term trends of the other climatic factors(fog days, tropical night days, etc) were also studied in this study.

Long-term Variation and Characteristics of Water Quality in the Asan Coastal Areas of Yellow Sea, Korea (아산연안 수질환경의 특성과 장기변동)

  • Park, Soung-Yun;Kim, Hyung-Chul;Kim, Pyoung-Joong;Park, Gyung-Soo;Park, Jeung-Sook
    • Journal of Environmental Science International
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    • v.16 no.12
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    • pp.1411-1424
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    • 2007
  • Long-term trends and distribution patterns of water quality were investigated in the Asan coastal areas of Yellow Sea, Korea from 1975 to 2005. Water samples were collected at 3 stations and physicochemical parameters were analyzed including water temperature, salinity, suspended solids(SS), chemical oxygen demand(COD), dissolved oxygen(DO) and nutrients. Spatial distribution patterns were not clear among stations but the seasonal variations were distinct except COD, SS and nitrate. The trend analysis by principal component analysis(PCA) during twenty years revealed the significant variations in water quality in the study area, Annual water qualities were clearly discriminated into 4 clusters by PCA; year cluster 1988-1991, 1994-1997, and 1992-1993/1998-2005. By this multi-variate analysis we can summarize the annual trends as the followings; salinity, suspended solids and dissolved oxygen tended to increase from late 1980's, increased pH and COD from 1992, and decreased salinity and increased nitrogen and COD from 1990 due to the runoff frow agricultural lands causing eutrophication.

A Study on the Reference Building based on the Building Design Trends for Non-residential Buildings (건축물 설계현황 분석을 통한 국내 비주거용 표준건물의 설정에 관한 연구)

  • Jeong, Young-Sun;Jung, Hae-Kwon;Jang, Hee-Kyung;Yu, Ki-Hyun
    • Journal of the Korean Solar Energy Society
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    • v.34 no.3
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    • pp.1-11
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    • 2014
  • The Korean government plans to introduce the building energy performance standard which regulates the annual energy consumption of buildings. This paper aimed to set up the reference building from database based on the building design trends for non-residential buildings. We surveyed the design data of 435 non-residential buildings which were granted building permission from 2007 to 2011. And we conducted estimation on the heating & cooling load and the energy consumption of the reference building using ECO2 program. From results, the reference building of non-residential buildings was office building which had a total 7 floors and $20,838m^2$ gross floor area. And it suggests the design reference data of building envelope, HAVC, heat source equipment and lighting system for the reference building. The total annual energy use of the reference building was $151.9kWh/m^2yr$.

Analysis of Spatial-temporal Variability and Trends of Extreme Precipitation Indices over Chungcheong Province, South Korea (충청지역 극한강우지수의 시공간적 경향과 변동성 분석)

  • Bashir, Adelodun;Golden, Odey;Seulgi, Lee;Kyung Sook, Choi
    • Journal of The Korean Society of Agricultural Engineers
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    • v.64 no.6
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    • pp.101-112
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    • 2022
  • Extreme precipitation events have recently become a leading cause of disasters. Thus, investigating the variability and trends of extreme precipitation is crucial to mitigate the increasing impact of such events. Spatial distribution and temporal trends in annual precipitation and four extreme precipitation indices of duration (CWD), frequency (R10 mm), intensity (Rx1day), and percentile-based threshold (R95pTOT) were analyzed using the daily precipitation data of 10 observation stations in Chungcheong province during 1974-2020. The precipitation at all observation stations, except the Boryeong station, showed nonsignificant increasing trends at 95% confidence level (CL) and increasing magnitudes from the west to east regions. The high variability in mean annual precipitation was more pronounced around the northeast and northwest regions. Similarly, there were moderate to high patterns in extreme precipitation indices around the northeast region. However, the precipitation indices of duration and frequency consistently increased from the west to east regions, while those of intensity and percentile-based threshold increased from the south to east regions. Nonsignificant increasing trends dominated in CWD, R10 mm, and Rx1day at all stations, except for R10 mm at Boeun station and Rx1day at Cheongju and Jecheon stations, which showed a significantly increasing trend. The spatial distribution of trend magnitude shows that R10 mm increased from the west to east regions. Furthermore, variations in precipitation were very strongly correlated (99% CL) with R10 mm, Rx1day, and R95pTOT at all stations, except with wR10 mm at Cheongju station, which was strongly correlated with a 95% CL.

Climate Change Assessment on Air Temperature over Han River and Imjin River Watersheds in Korea

  • Jang, S.;Hwang, M.
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.740-741
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    • 2015
  • the downscaled air temperature data over study region for the projected 2001 - 2099 period were then ensemble averaged, and the ensemble averages of 6 realizations were compared against the corresponding historical downscaled data for the 1961 - 2000 period in order to assess the impact of climate change on air temperature over study region by graphical, spatial and statistical methods. In order to evaluate the seasonal trends under future climate change conditions, the simulated annual, annual DJF (December-January-February), and annual JJA (June-July-August) mean air temperature for 5 watersheds during historical and future periods were evaluated. From the results, it is clear that there is a rising trend in the projected air temperature and future air temperature would be warmer by about 3 degrees Celsius toward the end of 21st century if the ensemble projections of air temperature become true. Spatial comparison of 30-year average annual mean air temperature between historical period (1970 - 1999) and ensemble average of 6-realization shows that air temperature is warmer toward end of 21st century compared to historical period.

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Trends on Racing Speed Traits in Thoroughbred Racehorses (더러브렛 경주마의 속도형질에 대한 추세 분석)

  • Park, Kyung-Do;Lee, Hak-Kyo;Jeon, Gwang-Joo;Kong, Hong-Sik;Cho, Byung-Wook;Cho, Kwang-Hyun;Son, Sam-Kyu
    • Journal of Animal Science and Technology
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    • v.50 no.6
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    • pp.747-752
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    • 2008
  • This study was carried out to calculate genetic trends on racing speed traits of Thoroughbred racehorses, using a total 208,043 racing records of 9,934 heads collected from January, 1990 to December, 2006 in Gwacheon racecourse. Repeated time, winning time and annual best time were used racing speed traits. The estimated heritabilities and repeatabilities for repeated time, winning time and annual best time were 0.288, 0.275, 0.341 and 0.502, 0.475, 0.496, respectively. Average phenotypic improvement per race year for racing speed traits were ranged from -0.115 to 0.148 second. The other side, the genetic improvement per race year for repeated time was -0.027 second but winning time and annual best time were not shown consistent trends. Therefore, we concluded that repeated time is recommended improvement trait of Thoroughbred racehorses.

Assessment of GCM and Scenario Uncertainties under Future Climate Change Conditions

  • Jang, S.;Hwang, M.;Park, J.;Lim, K.
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.658-659
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    • 2015
  • GCM and scenario uncertainties are first investigated for 5 major watersheds (Han River, Paldang dam, Namhan River, Bukhan River and Imjin River watersheds). As a result of this study, it is found that CCSM3-based annual precipitation increases linearly with respect to the 10-year moving average values while CSIRO-based precipitation does not show much of trend. The results from annual DJF mean precipitation show a similar trend with respect to their 10-year moving average values. Both CCSM3- and CSIRO-based annual JJA mean precipitation do not show much of trend toward 21st century. In general, CCSM3-based precipitation values are slightly higher than CSIRO-based values with respect to their annual and annual JJA mean precipitation values, but CSIRO-based annual DJF mean precipitation values are slightly higher than CCSM3-based values. In case of mean air temperature between CCSM3 and CSIRO during 21st century, all of results show a clear trend in warming with the passage of time for 5 watersheds. However the upward trends from CCSM3-based values slow down toward end of 21stcentury while CSRIO-based values increases almost linearly.

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Trend Analysis of Industrial Accidents in Manufacturing Industry (제조업 분야의 산업재해에 관한 경향 분석)

  • Jeong, Byung-Yong
    • IE interfaces
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    • v.9 no.2
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    • pp.231-238
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    • 1996
  • Records of industrial accidents are essential to maintain efficient and successful safety programs. The objective of this study is to examine the trends of industrial accidents in manufacturing industry, based on the national statistics. From 1972 to 1994, statistics of industrial accidents were extracted from the annual publications of Ministry of Labor. The results show that there are significant characteristics and trends in the records of industrial accidents. These findings identified in this study can be used to manage the accident prevention efforts.

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Analysis of Trend and Convergence for Science and Technology using the VOSviewer

  • Jeong, Dae-hyun;Koo, Youngduk
    • International Journal of Contents
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    • v.12 no.3
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    • pp.54-58
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    • 2016
  • In this study, articles of the science and technology field that had been monitored for the period from 2002 to 2013 using GTB (Global Trends Briefing) were analyzed. Specifically, the VOSviewer was used to analyze the annual science and technology trends by keyword and the science and technology standard-classification information indicated in the GTB articles, and the convergence trends were therefore monitored. The findings of this study show that active studies were under way in the fields of material science and new and renewable energy, and that convergence has progressed. This result indicates that the information of the articles on papers and patents is more reliable, as it can reflect the current trends more rapidly in the science and technology field than the paper information or the patent information that is traditionally used in analyses of science and technology information.

Temporal Trends and Spatial Comparisons of Ozone Concentrations in Jinju (진주시 오존농도의 시간적 추이와 공간적 비교)

  • Park, Jeong-Ho
    • Journal of Environmental Science International
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    • v.19 no.6
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    • pp.761-769
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    • 2010
  • Temporal trends of ozone concentration in Jinju were investigated by using observation data from 3 air quality monitoring stations for the period of 2004~2008. In addition, spatial comparisons of ozone concentration at Jeoguri, upwind and downwind directions of Jinju were investigated between May and September 2009. Annual mean exhibited increasing trends +1.7ppb/yr throughout the study period. In the case of diurnal variation, the lowest ozone concentration was shown from 7 am to 8 am and the highest around 4 pm. The ozone concentrations of Jeoguri station of the south coast were higher than Jinju. In particular, the upwind direction of Jinju had relatively hight ozone concentration