• Title/Summary/Keyword: precipitation events

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Impact of Climate Change on Food Safety: A Mini-review (기후변화와 식품안전에 관한 소고)

  • Kim, Jong-Gyu;Kim, Joong-Soon
    • Journal of Environmental Health Sciences
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    • v.42 no.6
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    • pp.465-477
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    • 2016
  • Objectives: This review examined the scientific evidence regarding the impact of climate change on food safety. Methods: The impact of climate change on food safety was assessed based on a survey of related publications reported in the past 20 years. The terms used for literature selection reflect three aspects: climate change; food; and food safety. Results: Climate change is expected to affect the key elements of food production - water and climate. These impact on food safety through many different pathways. Directly, food shortages according to the population grovoth result in a food security/food supply problem, These relationships are commonly understood. The indirect impacts include an increase in food-borne diseases and pathogens, increased mycotoxin production, and increased risk of pesticide residues in foods due to greater use of pesticides in response to warming and increased precipitation and the accompanying diseases in certain crops. Field studies and statistical and scenario analyses were performed to provide evidence. However, quantification of these relationships is still lacking. Conclusion: Adaptation measures at the local and community levels are essential since the pressures from weather and climate events may differ according to region and sector. It is recommended that we go beyond empirical observations of the association between climate change and food safety and develop more scientific explanations. We also need to explore alternative materials for bioenergy demands in order to improve sustainability.

Possible Mechanism Underlying the Antiherpetic Activity of a Proteoglycan Isolated from the Mycelia of Ganoderma lucidum in Vitro

  • Li, Zubing;Liu, Jing;Zhao, Yifang
    • BMB Reports
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    • v.38 no.1
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    • pp.34-40
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    • 2005
  • GLPG (Ganoderma lucidum proteoglycan) was a bioactive fraction obtained by the liquid fermentation of the mycelia of Ganoderma lucidum, EtOH precipitation, and DEAE-cellulose column chromatography. GLPG was a proteoglycan with a carbohydrate: protein ratio of 10.4: 1. Its antiviral activities against herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) were investigated using a cytopathic inhibition assay. GLPG inhibited cell death in a dose-dependent manner in HSV-infected cells. In addition, it had no cytotoxic effect even at 2 mg/ml. In order to study the mode of action of the antiviral activity of GLPG, cells were treated with GLPG before, during, and after infection, and viral titer in the supernatant of cell culture 48 h post-infection was determined using a $TCID_{50}$ assay. The antiviral effects of GLPG were more remarkable before viral treatment than after treatment. Although the precise mechanism has yet to be defined, our work suggests that GLPG inhibits viral replication by interfering with the early events of viral adsorption and entry into target cells. Thus, this proteoglycan appears to be a candidate anti-HSV agent.

Watershed-based PMF and Sediment-runoff Estimation Using Distributed Hydrological Model (분포형 수문모형을 이용한 유역기반의 PMF 및 유사-유출량 산정)

  • Yu, Wansik;Lee, Giha;Kim, Youngkyu;Jung, Kwansue
    • Journal of The Korean Society of Agricultural Engineers
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    • v.60 no.2
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    • pp.1-11
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    • 2018
  • Probable Maximum Flood (PMF) is mostly applied for the designs of large-scale hydraulic structures and it is estimated by computing the runoff hydrograph where Probable Maximum Precipitation (PMP) is inserted as design rainfall. The existing PMP is estimated by transferring the heavy rainfall from all watersheds of korea to the design watershed, however, in this study, PMP was analyzed by selecting only rainfall events occurred in the design watershed. And then, Catchment-scale Soil Erosion Model (CSEM) was used to estimate the PMF and sediment-runoff yield according to the watershed-based estimated PMP. Although the PMF estimated in this study was lower than the existing estimated PMF in the Yongdam-dam basin, it was estimated to be higher than the 200-year frequency design flood discharge. In addition, sediment-runoff yield was estimated with a 0.05 cm of the maximum erosion and a 0.06 cm of the maximum deposition, and a total sediment-runoff yield of 168,391 tons according to 24-hour PMP duration.

The Estimation of Contribution Ratio for Sub Stream in Nam River Basin (남강유역 지류·지천별 영향도 평가)

  • Lee, Jae-Woon;Kwon, Heon-Gak;Kwak, In-Soo;Youn, Jong-Soo;Cheon, Se-Uk
    • Journal of Environmental Impact Assessment
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    • v.21 no.5
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    • pp.745-755
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    • 2012
  • The relations between tributaries and mainstream were identified with the water qualities measurements in the field. Parameters of water qualities were BOD, T-N, T-P and measurements were performed by 4 events of rainfalls for 2011. The precipitation data influenced on pollutants loads. Pollutants loads were fluctuations with the seasonal variation. Gajoacheon contributed in 18.39% of BOD, 23.79% of T-N, 15.23% of T-P and Nabulcheon contributed in 13.54% of BOD, 13.05% of T-N and 13.66% of T-P in the region from Nam River_C to Nam River_D. In case of the region from Nam River_C to Nam River_D, Yongacheon river inflowed to main stream as 23.65% of BOD, 20.74% of T-N, and 15.05% of T-P.

Characteristics of Aerosol Size Distribution from OPC Measurement in Seoul, 2001 (OPC(광학적 입자 계수기)로 측정한 2001년 서울지역 에어로졸의 입경 분포)

  • 정창훈;전영신;최병철
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.5
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    • pp.515-528
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    • 2003
  • The characteristics of one year observation aerosol data in Seoul, 200 I was studied using an OPC (Optical Particle Counter). The size resolved aerosol number concentrations of 0.3 ∼ 25 11m were measured. The results were compared with PM$_{10}$ mass concentration data under various meteorological conditions including dust and precipitation events. For fine particles whose diameter is less than 2.23 ${\mu}{\textrm}{m}$, the number concentration increases in the early morning which is considered due to transportation. while the coarse mode particles increase during daytime. This increase can be explained as local sources and human activities near sampling site. Hourly averaged data show that there exists diurnal variation. Generally, PM$_{10}$ data showed a similar tendency with OPC data. The size resolved OPC data showed that the particles of 0.5 ∼ 3.67 ${\mu}{\textrm}{m}$ are positively correlated with PM$_{10}$ data. The accumulated volume fraction of size resolved aerosol concentration in 0.5 ∼ 10 ${\mu}{\textrm}{m}$ showed that 0.5 ∼ 2.23 ${\mu}{\textrm}{m}$ particles occupied 59.2% of total aerosol volume of 0.5 ∼ 10 ${\mu}{\textrm}{m}$./TEX>.

Development of Storage Management System for Small Dams (소규모 댐의 저수관리 시스템 개발)

  • Kim, Phil-Shik;Kim, Sun-Joo
    • Journal of The Korean Society of Agricultural Engineers
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    • v.47 no.3
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    • pp.15-25
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    • 2005
  • Ninety tow percent of over 1,800 gate controlled dams in Korea are classified as small dams. The primary purpose of these small dams is to supply irrigation water. Therefore, while large dams can store as much as 80 percent of precipitation and thus are efficient to control flood, small dams are often lack of flood control function resulting in increased susceptibility drought and flood events. The purpose of this study is to develope a storage management model for irrigation dams occupying the largest portion of small dams. The proposed Storage Management Model (STMM) can be applied to the Seongju dam for efficient management. Besides, the operation standard is capable of analyzing additional available water, considering water demand and supply conditions of watershed realistically. And the model can improve the flood control capacity and water utilization efficiency by the flexible operation of storage space. Consequently, if the small dams are managed by the proposed Storage management model, it is possible to maximize water resources securance and minimize drought and flood damages.

A Study on the Algorithm for Estimating Rainfall According to the Rainfall Type Using Geostationary Meteorological Satellite Data (정지궤도 기상위성 자료를 활용한 강우유형별 강우량 추정연구)

  • Lee Eun-Joo;Suh Myoung-Seok
    • Proceedings of the KSRS Conference
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    • 2006.03a
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    • pp.117-120
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    • 2006
  • Heavy rainfall events are occurred exceedingly various forms by a complex interaction between synoptic, dynamic and atmospheric stability. As the results, quantitative precipitation forecast is extraordinary difficult because it happens locally in a short time and has a strong spatial and temporal variations. GOES-9 imagery data provides continuous observations of the clouds in time and space at the right resolution. In this study, an power-law type algorithm(KAE: Korea auto estimator) for estimating rainfall based on the rainfall type was developed using geostationary meteorological satellite data. GOES-9 imagery and automatic weather station(AWS) measurements data were used for the classification of rainfall types and the development of estimation algorithm. Subjective and objective classification of rainfall types using GOES-9 imagery data and AWS measurements data showed that most of heavy rainfalls are occurred by the convective and mired type. Statistical analysis between AWS rainfall and GOES-IR data according to the rainfall types showed that estimation of rainfall amount using satellite data could be possible only for the convective and mixed type rainfall. The quality of KAE in estimating the rainfall amount and rainfall area is similar or slightly superior to the National Environmental Satellite Data and Information Service's auto-estimator(NESDIS AE), especially for the multi cell convective and mixed type heavy rainfalls. Also the high estimated level is denoted on the mature stage as well as decaying stages of rainfall system.

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Operation Strategy of Groundwater Dam Using Estimation Technique of Groundwater Level (지하수위 예측기법을 활용한 지하댐 운영전략)

  • Bu, Seong-An;Sin, Sang-Mun;Choe, Yong-Seon;Park, Jae-Hyeon;Jeong, Gyo-Cheol;Park, Chang-Geun
    • KCID journal
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    • v.13 no.2
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    • pp.236-245
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    • 2006
  • Among a number of methodologies for developing groundwater supply to overcome drought events reported in the research community, an accurate estimation of the groundwater level is an important initial issue to provide an efficient method for operating groundwater. The primary objective of this paper is to develop an advanced prediction model for the groundwater level in the catchment area of the Ssangcheon groundwater dam using precipitation based period dividing algorithm and response surface methodology (RSM). A numerical example clearly shows that the proposed method can effectively forecast groundwater level in terms of correlation coefficient ($R^2$) in the upstream part of the Ssangcheon groundwater dam.

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Monitoring of Non-point Source Pollutants Generated by a Flower Farm

  • Choi, Byoungwoo;Kang, Meea
    • The Journal of Engineering Geology
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    • v.24 no.4
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    • pp.463-471
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    • 2014
  • This paper considers the effect of rainfall on non-point source (NPS) pollutant loads. The impact of runoff on the occurrence of NPS pollutants was found to be influenced by rainfall amount, rainfall intensity, and the number of antecedent dry days (ADD), both independently and in combination. The close correlation ($R^2$ = 0.9920) between rainfall and runoff amounts was demonstrated at the study site (a flower farm) over the period between January 2011 and December 2013. The relationships among pollutant levels, runoff, and rainfall was not satisfactory results except for the Biochemical Oxygen Demand ($BOD_5$). The correlation coefficients between $BOD_5$, and both runoff and rainfall, were greater than 0.92. However, the relationships of other pollutants, such as Suspended Solid (SS), Chemical Oxygen Demand ($COD_{Mn}$), Total Nitrogen (TN), and Total Phosphorus (TP), with runoff and rainfall had correlation coefficients of less than 0.70. The roles of rainfall was different from rainfall categories on the occurrence of runoff. Instantaneous rainfall intensity was a principle factor on the occurrence of runoff following light rainfall events (total ${\leq}30mm$). For rainfall of intermediate intensity (total precipitation 31-50 mm), the combined effect of both average rainfall intensity and ADD was found to influence runoff generation. We conclude that the control of NPS pollutants with the reflection of the climate change that makes the remarkable effect of amounts and forms on the rainfall and runoff.

Assessment of the ENSO influences on rainfall Characteristics and Frequency analysis (남방진동지수가 강우특성과 빈도분석에 미치는 영향 분석)

  • Kim, Byung-Sik;Oh, Je-Seung;Kim, Chi-Yung
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.1619-1624
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    • 2007
  • The rainfall frequency estimations are critical in the design of hydraulic structures (such as bridges and culverts) to ensure that they are built economically and safely. In other words, they are not over designed or under designed. However one of the main assumptions in the creation of these analysis is that the rainfall data for a site is stationary. That is, climatic trends and variability in a region have negligible effects on the curves. But as has been proved in recent history, climatic variability and trends do exist and their effects on precipitation have not been negligible. Increasing occurrences of the El Nino phenomenon have lead to droughts and floods around the world, and long term trends in rainfall, both increases and decreases, have been seen in all regions across Korea. The purpose of this paper is to investigate and evaluate impacts of ENSO on rainfall characteries and rainfall frequency estimations in Korea. In this paper, The available rainfall data were categorized into Warm(EL Nino), Cold(La Nina), Normal episodes based on the Cold & Warm Episodes by Season then 50 years of daily rainfall data were generated for each episodic events(EL Nino, La Nina)

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