• Title/Summary/Keyword: Long-term changes

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An Analysis of Long-Term Variation of PM10 Levels and Local Meteorology in Relation to Their Concentration Changes in Jeju (제주지역 미세먼지의 장기변동 및 농도변화에 관한 국지기상 분석)

  • Park, Yeon-Hee;Song, Sang-Keun;Lee, Soo-Jeong;Kim, Suk-Woo;Han, Seung-Bum
    • Journal of Environmental Science International
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    • v.25 no.1
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    • pp.107-125
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    • 2016
  • Long-term variations of $PM_{10}$ and the characteristics of local meteorology related to its concentration changes were analyzed at 4 air quality sites (Ido-dong, Yeon-dong, Donghong-dong, and Gosan) in Jeju during two different periods, such as PI (2001-2006) and PII (2007-2013), over a 13-year period. Overall, the long-term trend of $PM_{10}$ was very slightly downward during the whole study period, while the high $PM_{10}$ concentrations in PII were observed more frequently than those in PI. The concentration variations of $PM_{10}$ during the study period was clarified in correlation between $PM_{10}$ and meteorological variables, e.g. the low (high) $PM_{10}$ concentration with large (small) precipitation or high (low) radiation and in part high $PM_{10}$ concentrations (especially, Donghong-dong and Gosan) with strong wind speed and the westerly/northwesterly winds. This was likely to be caused by the transport effect (from the polluted regions of China) rather than the contribution of local emission sources. The $PM_{10}$ concentrations in "Asian dust" and "Haze" weather types were higher, whereas those in "Precipitation", "Fog", and "Thunder and Lighting" weather types were lower. The contribution of long-range transport to the observed $PM_{10}$ levels in the urban center (Ido-dong, Yeon-dong, and Donghong-dong), if estimated by comparison to the data of the background site (Gosan), was found to explain about 80% (on average) of its input.

Long-term impacts of Argentine ant invasion of urban parks in Hiroshima, Japan

  • Park, Sang-Hyun;Hosoishi, Shingo;Ogata, Kazuo
    • Journal of Ecology and Environment
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    • v.37 no.3
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    • pp.123-129
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    • 2014
  • Ant communities are well suited for monitoring changes in ecosystems. Although numerous studies have examined the responses of ant communities to environmental disturbance, relatively few long-term studies on ant communities have been undertaken in urban environments. We examined species richness in nine urban parks in Hiroshima, Japan, and compared the survey results with data collected at the same sites by using the same methods in 1999. In both surveys, total of 25 species was recorded: 23 species in 1999 and 20 species in 2012. Non-metric multidimensional scaling analysis revealed that the ant communities consisted of two distinct groups, which could in turn be characterized by three patterns of ant community changes in between the two groups. The first of these community change patterns was characterized by a shift within group 1, but the number of species remained constant (approx. 10 species). The second pattern was characterized by a shift within group 2, but the number of species remained low (approx. 4 species). The third pattern was characterized by a shift from group 1 to group 2 as the abundance of Linepithema humile (Mayr) increased over time. Unlike the first and second patterns, the number of ant species in communities of the third type decreased significantly. These findings suggest that L. humile has a marked effect on the species diversity of indigenous ant communities in urban environments.

Case Report of Efficacy and Safety of Long Term Medication of Oncheongeum-gamibang (온청음 가미방 3개월간 장기복용의 유효성과 안전성 보고)

  • Lee, Sang Young;Kang, Hwi Joong;Jung, Min Young
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.27 no.2
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    • pp.268-272
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    • 2013
  • This study is designed as pilot study to report the efficacy and safety of long term medication of Oncheongeum-gamibang on atopic dermatitis. The patient of atopic dermatitis was asked to take Oncheongeum-gamibang for 3 months. Every end of month, he had gotten hematological test and SCORAD Index examination. After the clinical trial was done, he had additional examination to see the changes and duration of medicinal effect. During the period of taking Onchung-um, estimation of symptoms by SCORAD Index examination showed little bit of improvement while taking medicine and after one month, the improvement was maintained. There were no significant changes in hematologic test and liver function test during and at the end of the clinical trial. We were able to find out that it is effective and safe to take long term medication of Oncheongeum-gamibang for an individual. However, due to deficiency of the cases and immunological values, there will be additional study to make up for better result.

Long-term changes of water quality with regard to main Pollutant Sourses in Agricultural Reservoirs (주오염원별 농업용저수지의 장기 수질특성변화)

  • Choi, Sun-Hwa;Kim, Ho-Il;Yoon, Kyung-Seup;Park, Jong-Min
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2002.10a
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    • pp.425-428
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    • 2002
  • This study has been carried out to analized of long term changes of water quality with regard to main pollutant sources in agricultural reservoirs on the basis of data during 1996-2001. The major source was domestic wastewater(DWW) and water pollution by non-point sources(NPS) is increasing as time goes. It was determined that Seasonly average values of DWW were pH $7.6{\sim}8.7$, COD $7.0{\sim}9.4$, T-N $0.74{\sim}2.07$, T-P $0.05{\sim}0.62$, Live-stock wastewater(LWW) were pH $7.5{\sim}8.9$, COD $5.5{\sim}9.8$, T-N $0.57{\sim}1.91$, T-P $0.04{\sim}0.13$, NPS were pH $7.1{\sim}8.3$, COD $3.1{\sim}5.2$, T-N $0.29{\sim}1.44$, T-P $0.02{\sim}0.07$. Fluctuation of DWW and LWW were very wide and variable long term patterns of them were similar. Trophic states by Carlson Index of DWW and LWW was classified as eutrophic to hypretrophic from chl-a, T-P concentration.

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Effect of long-term thermal aging on the microstructural and mechanical characteristics of nickel-based alloy weldment (니켈계 합금 용접부의 미세조직 및 기계적 특성에 대한 장기 열적 시효의 영향)

  • Yoo, Seung Chang;Ham, Junhyuk;Kim, Ji Hyun
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.12 no.1
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    • pp.41-48
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    • 2016
  • To investigate the effect of long-term thermal aging on the microstructural and mechanical characteristics of weldment made of nickel base alloy and its weld metal, an accelerated heat treatment was applied to simulate the process of long-term thermal aging in the operating condition of nuclear power plant. A representative nickel-based weldment with Alloy 600 and Alloy 182 was fabricated and heat-treated at $400^{\circ}C$ for 1,713 h and 3,427 h to simulate the thermal aging for the period equivalent to 15 and 30 years in operating pressurized water reactors, respectively. The microstructural and mechanical characteristics were analyzed by using optical microscopy, scanning electron microscopy and Vickers microhardness measurement. Changes were observed in precipitation behavior and microhardness of each specimen, and these changes were mainly attributed to the change in precipitated morphology and residual stress across the weld during the thermal aging process.

Future Development Strategies for East Asian Journal of Business Economics

  • Byoung-Goo KIM
    • Journal of Research and Publication Ethics
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    • v.4 no.2
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    • pp.13-17
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    • 2023
  • Purpose: EAJBE is actively responding to changes in academic paradigms at domestic and abroad and is carrying out measures to maximize synergy effects between academic fields with the goal of being at the world level. This study aims to present a developmental strategy for EAJBE to grow into an academic journal with international public trust and prepare for future changes. Research design, data and methodology: This paper identifies the current status from the first issue of EAJBE to the present, and analyzes the overall development strategy and direction. Results: EAJBE continues to strengthen long-term investment for internationalization and activities to attract members of excellent scholars. Specifically, first of all, EAJBE aims to operate responsible academic journals, such as guaranteeing the long term of the president of the academic society, the chairman of the editorial board, and the editor-in-chief. EAJBE also focuses on expanding investment for internationalization from a long-term perspective. Finally, EAJBE actively strives for academic exchanges between scholars abroad and at home. Conclusions: EAJBE was indexed in the KCI of the Korea Research Foundation and currently operates a rigorous academic journal to be indexed in the SCOPUS. Already, EAJBE is doing its best to become a successful model for Korean academic journals. EAJBE's path forward will be the first one that no academic society has ever reached as the world's top academic journal.

Long Term Analysis of PM10 Concentration in Seoul Using KZ Filter (KZ 필터법을 이용한 서울지역 미세먼지 농도의 장기변화 분석)

  • Lee, Jung-Young;Kong, Boo-Joo;Han, Jin-Seok;Lee, Min-Do
    • Journal of Korean Society for Atmospheric Environment
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    • v.24 no.1
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    • pp.63-71
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    • 2008
  • Local meteorological conditions exert a strong influence over day-to-day variations in air pollutant concentrations. Therefore, the meteorological fluctuations have to be removed in order for air quality planners and managers to examine underlying emissions-related trends and make better air quality management decisions for future. In this study, the meteorologically adjusted $PM_{10}$ trends in Seoul are investigated over the period $1999{\sim}2006$ using Kolmogorov-Zurbenco (KZ) filter. The result indicated that meteorologicaJ variability accounts for about 25% of $PM_{10}$ variability. Both the meteorologically adjusted and unadjusted Jong-term daily $PM_{10}$ concentrations had a significant downward trends and the difference between the meteorologically adjusted and unadjusted was small. So it was assumed that in long-term daily $PM_{10}$ changes, localized changes in emissions is more important than the changes caused by meteorological conditions.

Short-Term Production Planning of an Automated Manufacturing System (자동화된 제조시스템에서의 단기간 생산계획)

  • 김진규
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.14 no.24
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    • pp.43-52
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    • 1991
  • The short-term production planning of an automated manufacturing system is to determine the production rate of each part type or family of part types. The purpose of this paper is to develop an optimal algorithm for solving the short-term production planning problem while machine failures, repairs. and changes in demand requirements are anticipated. The problem is formulated by LP and it shows that the production surplus is approached or stays at the hedging point. In addition, the long-term average frequencies of set-us with relation to a multilevel hierarchical production planing scheme are considered An example to show the effectiveness of the algorithm is presented.

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