• Title/Summary/Keyword: KM research method

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Rainfall analysis considering watershed characteristics and temporal-spatial characteristics of heavy rainfall (집중호우의 시·공간적 특성과 유역특성을 고려한 강우분석 연구)

  • Kim, Min-Seok;Choi, Ji-Hyeok;Moon, Young-Il
    • Journal of Korea Water Resources Association
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    • v.51 no.8
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    • pp.739-745
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    • 2018
  • Recently, the incidence of heavy rainfall is increasing. Therefore, a rainfall analysis should be performed considering increasing frequency. The current rainfall analysis for hydrologic design use the hourly rainfall data of ASOS with a density of 36 km on the Korean Peninsula. Therefore, medium and small scale watershed included Thiessen network at the same rainfall point are analyzed with the same design rainfall and time distribution. This causes problem that the watershed characteristics can not be considered. In addition, there is a problem that the temporal-spatial change of the heavy rainfall occurring in the range of 10~20 km can not be considered. In this study, Author estimated design rainfall considering heavy rainfall using minutely rainfall data of AWS, which are relatively dense than ASOS. Also, author analyzed the time distribution and runoff of each case to estimate the huff's method suitable for the watershed. The research result will contribute to the estimation of the design hydrologic data considering the heavy rainfall and watershed characteristics.

Calculation of low flow for estimating TMDL (허용 부하량 산정을 위한 저수유량 산정 방안)

  • Jung, Yoon-Min;Kwon, Jae-Hyuk;Kang, Sang-Hyuk
    • Spatial Information Research
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    • v.17 no.2
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    • pp.223-239
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    • 2009
  • The low fow analysis for small-mid sized river basins is very difficult because of insufficient flow data or ungauged basins. The objective of this study is to suggest effective method of low flow using area function method for calculating Total Maximum Daily Loads (TMDL) by considering environmental carrying capacity. Two watersheds which are Juchon watershed having $606km^2$ areas and ungauged watershed having $4,551km^2$ areas were selected for this study. As a result of application, the low flow in the downstream of Juchon River and the Han River after confluence of Okdong River were $1.9m^3/s$ and $20.7m^3/s$, respectively. Then we consider the target BOD of 1.0-1.2mg/l in Youngwol prefecture, the TDML was estimated 164-197kg/day and 1,788-2,146kg/day, respectively. This approach will useful for estimating TDML to insufficient watershed of flow data and ungauged watershed of flow data.

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Policy Decision Making Through Wildlife Habitat Potential With Space Value Categorization (야생동물 서식지 잠재력과 공간가치분류를 통한 정책방향 설정)

  • Jang, Raeik;Lee, Myungwoo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.18 no.1
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    • pp.1-12
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    • 2015
  • Beginning of the human ecology in 1920s, the efforts for applying the environmental values to a policy have been embodied by the enactments of international agreement and relevant laws. The government has been struggling to adopt the environmental values for the policy by enacting the relevant laws and establishing the environmental value evaluation information (environmental conservation value assessment map, eco-natural map, biotope map). In spite of the efforts to apply the environmental value assessment information for the habitat potential of wildlife, the application is being challenged by the discrepancy in methods and criteria. Thus this study intends to measure the potential of wildlife habitat and apply it to the spatial value classification for the application plan of wildlife habitat potential in policy. Maxent was used for the habitat potential and the land types were classified depending on the surface and land use pattern of cadastral map. As a result, the policy matrix including conservation strategy(CS), restoration strategy(RS), practical use strategy(PS) and development strategy(DS) has been deduced as CS $13.05km^2$(2.38%), RS $1.64km^2$(0.30%), PS $162.42km^2$(29.57%) and DS $8.56km^2$(1.56%). CS was emerged mostly on forest valleys and farmlands, and RS was appeared in the road area near the conservation strategy areas. Boryung downtown and Daecheon Beach were the center of DS, while the forest and farmlands were presented as PS. It is significant that this study suggest the new approaching method by comparing the wildlife habitat potential with the land type. Since this study evaluated the environmental value by one species of leopard cat (Prionailurusbengalensis) with Maxent model, it is necessary to apply the habitat potential measuring method for various target species as further research.

Freeway Design Capacity Estimation through the Analysis of Time Headway Distribution (차두시간분포 분석을 통한 고속도로 설계용량 산정모형의 개발)

  • Kim, Jum San;Park, Chang Ho
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.2D
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    • pp.251-258
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    • 2006
  • This study is to develop an estimation method of freeway design capacity through the analysis of time headway distribution in continuum flow. Traffic flow-speed diagram and time headway distribution plotted from individual vehicle data shows: a) a road capacity is not deterministic but stochastic, b) time headway distribution for each vehicle speed group follows pearson type V distribution. The freeway design capacity estimation model is developed by determining a minimum time headway for capacity with stochastic method. The estimated capacity values for each design speed are lower when design speed ${\leq}80km/h$, and higher when design speed ${\geq}106km/h$ in comparison with HCM(2000)'s values. In addition, The distinguish difference is that this model leads flexible application in planning level by defining the capacity as stochastic distribution. In detail, this model could prevent a disutility to add a lane for only one excess demand in a road planning level.

Effects of Observation Network Density Change on Spatial Distribution of Meteorological Variables: Three-Dimensional Meteorological Observation Project in the Yeongdong Region in 2019 (관측망 밀도 변화가 기상변수의 공간분포에 미치는 영향: 2019 강원영동 입체적 공동관측 캠페인)

  • Kim, Hae-Min;Jeong, Jong-Hyeok;Kim, Hyunuk;Park, Chang-Geun;Kim, Baek-Jo;Kim, Seung-Bum
    • Atmosphere
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    • v.30 no.2
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    • pp.169-181
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    • 2020
  • We conducted a study on the impact of observation station density; this was done in order to enable the accurate estimation of spatial meteorological variables. The purpose of this study is to help operate an efficient observation network by examining distributions of temperature, relative humidity, and wind speed in a test area of a three-dimensional meteorological observation project in the Yeongdong region in 2019. For our analysis, we grouped the observation stations as follows: 41 stations (for Step 4), 34 stations (for Step 3), 17 stations (for Step 2), and 10 stations (for Step 1). Grid values were interpolated using the kriging method. We compared the spatial accuracy of the estimated meteorological grid by using station density. The effect of increased observation network density varied and was dependent on meteorological variables and weather conditions. The temperature is sufficient for the current weather observation network (featuring an average distance about 9.30 km between stations), and the relative humidity is sufficient when the average distance between stations is about 5.04 km. However, it is recommended that all observation networks, with an average distance of approximately 4.59 km between stations, be utilized for monitoring wind speed. In addition, this also enables the operation of an effective observation network through the classification of outliers.

Potential application of herbal medicine treatment based on pattern identification for canine cognitive dysfunctional syndrome: a comparative analysis of Korea medicine therapy for patients with dementia (반려견 인지기능장애증후군에 대한 한의 진단 및 한약치료 적용 가능성 고찰: 치매환자 국내한의치료기술과 비교 분석)

  • Jung, Kyungsook;Zhao, HuiYan;Choi, Yujin;Jang, Jung-Hee
    • Korean Journal of Veterinary Research
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    • v.62 no.3
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    • pp.25.1-25.9
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    • 2022
  • Canine cognitive dysfunction syndrome (CDS) is a neurodegenerative disease that causes cognitive and behavioral disorders and reduces the quality of life in dogs and their guardians. This study reviewed the complementary and alternative medicine (CAM) for CDS and compared the diagnosis and therapy of CAM between CDS in canines and dementia in humans. The evaluation tools for the diagnosis of CDS and dementia were similar in the neurological and neuropsychiatric examinations, daily life activity, cognitive tests, and neuroimaging, but the evaluation for dementia was further subdivided. In CAM, pattern identification is a diagnostic method for accurate, personalized treatment, such as herbal medicine. For herbal medicine treatment of cognitive impairment in canines and humans, a similar pattern identification classified as deficiency (Qi, blood, and Yin) and Excess (phlegm, Qi stagnation, and blood stasis) is being used. However, the veterinary clinical basis for verifying the efficacy and safety of CAM therapies for CDS is limited. Therefore, based on CAM evidence in dementia, it is necessary to establish CDS-targeted CAM diagnostic methods and therapeutic techniques considering the anatomical, physiological, and pathological characteristics of dogs.

Study on Merging Method of SSTs Using Multi-satellite Data (다종 위성 자료를 활용한 해수면온도(SST) 합성기법 개발 연구)

  • Oh, Eun-Kyung;Yang, Chan-Su
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.17 no.3
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    • pp.197-202
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    • 2011
  • This study introduces a technique to merge three different sea surface temperature(SST) data obtained from multi-satellite sensors. NGSST algorithm, the most popular method of related society, estimates a center pixel of target SST using temporal and spatial correlations, excluding SST accuracies according to sensing methods or properties of satellites. We suggest a merging method of SST to consider the accuracy by satellite or sensor with a comparison with NGSST method. The data used for a merged daily SST with spatial resolution of 5 km was applied from three different satellite sensors such as MODIS, AVHRR and AMSR-E from April 2 to 4, 2011 around the southern coast of Korea. Results of the comparisons showed that the new method is higher than the NGSST method and its STDEV represents a comparatively low value. In future we are planning to compare and analyze the datasets during the daytime as well as nighttime over total cycle of the day.

New TLE generation method based on the past TLEs (과거 TLE정보를 활용한 새로운 TLE정보 생성기법)

  • Cho, Dong-Hyun;Han, Sang-Hyuck;Kim, Hae-Dong
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.45 no.10
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    • pp.881-891
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    • 2017
  • In this paper, we described the new TLE(Two Line Elements) generation method based on the compansation technique by using past TLEs(Two Line Elements) released by JSpOC(Joint Space Operation Center) in USA to reduce the orbit prediction error for long duration of SGP4(Simplified General Perturbations 4) which is a simplifed and analytical orbit propagator. The orbital residuals the orbital difference between two ephemeris for the first TLE only and for the all TLEs updated by JSpOC for the past some period was applied for this algorithm instead of general orbit determination software. Actually, in these orbital residuals, the trend of orbit prediction error from SGP4 is included. Thus, it is possible to make a simple residual function from these orbital residulas by using the fitting process. By using these residual functions with SGP4 prediction data for the currnet TLE data, the compansated orbit prediction can be reconstructed and the orbit prediction error for long duration of SGP4 is also reduced. And it is possible to generate new TLE data from it. In this paper, we demonstraed this algorithm in simple simulation, and the orbital error is decreased dramatically from 4km for the SGP4 propagation to 2km for it during 7 days as a result.

ATMOSPHERIC CORRECTION TECHNIQUE FOR GEOSTATIONARY OCEAN COLOR IMAGER (GOCI) ON COMS

  • Shanmugam, Palanisamy;Ahn, Yu-Hwan
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.467-470
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    • 2006
  • Geostationary Ocean Color Imager (GOCI) onboard its Communication Ocean and Meteorological Satellite (COMS) is scheduled for launch in 2008. GOCI includes the eight visible-to-near-infrared (NIR) bands, 0.5km pixel resolution, and a coverage region of 2500 ${\times}$ 2500km centered at 36N and 130E. GOCI has had the scope of its objectives broadened to understand the role of the oceans and ocean productivity in the climate system, biogeochemical variables, geological and biological response to physical dynamics and to detect and monitor toxic algal blooms of notable extension through observations of ocean color. To achieve these mission objectives, it is necessary to develop an atmospheric correction technique which is capable of delivering geophysical products, particularly for highly turbid coastal regions that are often dominated by strongly absorbing aerosols from the adjacent continental/desert areas. In this paper, we present a more realistic and cost-effective atmospheric correction method which takes into account the contribution of NIR radiances and include specialized models for strongly absorbing aerosols. This method was tested extensively on SeaWiFS ocean color imagery acquired over the Northwest Pacific waters. While the standard SeaWiFS atmospheric correction algorithm showed a pronounced overcorrection in the violet/blue or a complete failure in the presence of strongly absorbing aerosols (Asian dust or Yellow dust) over these regions, the new method was able to retrieve the water-leaving radiance and chlorophyll concentrations that were consistent with the in-situ observations. Such comparison demonstrated the efficiency of the new method in terms of removing the effects of highly absorbing aerosols and improving the accuracy of water-leaving radiance and chlorophyll retrievals with SeaWiFS imagery.

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Analysis of experimental studies on Insamyangyoung-tang (인삼양영탕을 이용한 실험연구 분석)

  • Choi, Song Ie;Kim, Yun Hee;Lee, Hye Won
    • Journal of Society of Preventive Korean Medicine
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    • v.19 no.2
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    • pp.145-157
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    • 2015
  • Objective : This study aimed to analyze a comprehensive feature of experimental research on Insamyangyoungtang and develop a strategy that can be used for experimental studies on Insamyangyoung-tang in the future. Method : The journal search was performed using six databases : PubMed, Chinese database (China Network Knowledge Infrastructure, [CNKI]), Japan database (Japan Science and Technology Information Aggregator, Electronic, [J-STAGE]) and three Korean databases (Oriental Medicine Advanced Searching Integrated System [OASIS], Research Information Service System [RISS], and Korean Studies Information Service System [KISS]). We used limited keywords and analyzed studies by publication year, experimental models, and the subjects of biological activities. The mechanism of pharmacological activity in accordance with the therapeutic effects of Insamyangyoung-tang was noted. Results and Conclusion : A total of 43 studies (6 domestic studies and 37 foreign ones) were examined according to the inclusion criteria of the experimental study. Research on the pharmacological activities of Insamyangyoung-tang showed its therapeutic effects on the nervous and immune systems, as well as its anti-aging, anti-fatigue, and hematopoietic effects. Additional efficacy and safety assessments and experimental and clinical studies should be performed to evaluate the mechanism of Insamyangyoung-tang. The present review has provided preliminary information for further studies on Insamyangyoung-tang.