• Title/Summary/Keyword: Weather characteristic

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Selection of Long-Term Pavement Performance Sections for Development of Distress Prediction Model in National Asphalt Pavement (국도 아스팔트 포장 파손예측모델 개발을 위한 장기 관측 구간 선정에 관한 연구)

  • Kwon, Soo-Ahn;Yoo, Pyeong-Joon;Kim, Ki-Hyun;Cho, Yoon-Ho
    • International Journal of Highway Engineering
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    • v.4 no.1 s.11
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    • pp.123-134
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    • 2002
  • Special pavement test sections were selected to develop a distress prediction model on asphalt pavement of National Highway. Experimental design was conducted for the selection of LTPP sections on in-service pavement(new and overlaid pavement) using several variables affecting pavement performance. Preliminary sections that satisfied the design template were chosen from the national highway database, and final selection was fixed through field inspection. The number of monitoring section is 95 including 47 overlaid pavement. A pavement distress data such as crack and rutting were collected for two years. An interim pavement performance analysis was peformed to show feasibility of performance monitoring program. Data related pavement such as traffic, weather, material characteristic and crack etc. should be collected for next project years and distress prediction model will be developed through the statistical analysis.

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A Comparative Assessment of the Efficacy of Frequency Ratio, Statistical Index, Weight of Evidence, Certainty Factor, and Index of Entropy in Landslide Susceptibility Mapping

  • Park, Soyoung;Kim, Jinsoo
    • Korean Journal of Remote Sensing
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    • v.36 no.1
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    • pp.67-81
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    • 2020
  • The rapid climatic changes being caused by global warming are resulting in abnormal weather conditions worldwide, which in some regions have increased the frequency of landslides. This study was aimed to analyze and compare the landslide susceptibility using the Frequency Ratio (FR), Statistical Index, Weight of Evidence, Certainty Factor, and Index of Entropy (IoE) at Woomyeon Mountain in South Korea. Through the construction of a landslide inventory map, 164 landslide locations in total were found, of which 50 (30%) were reserved to validate the model after 114 (70%) had been chosen at random for model training. The sixteen landslide conditioning factors related to topography, hydrology, pedology, and forestry factors were considered. The results were evaluated and compared using relative operating characteristic curve and the statistical indexes. From the analysis, it was shown that the FR and IoE models were better than the other models. The FR model, with a prediction rate of 0.805, performed slightly better than the IoE model with a prediction rate of 0.798. These models had the same sensitivity values of 0.940. The IoE model gave a specific value of 0.329 and an accuracy value of 0.710, which outperforms the FR model which gave 0.276 and 0.680, respectively, to predict the spatial landslide in the study area. The generated landslide susceptibility maps can be useful for disaster and land use planning.

Onion yield estimation using spatial panel regression model (공간 패널 회귀모형을 이용한 양파 생산량 추정)

  • Choi, Sungchun;Baek, Jangsun
    • The Korean Journal of Applied Statistics
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    • v.29 no.5
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    • pp.873-885
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    • 2016
  • Onions are grown in a few specific regions of Korea that depend on the climate and the regional characteristic of the production area. Therefore, when onion yields are to be estimated, it is reasonable to use a statistical model in which both the climate and the region are considered simultaneously. In this paper, using a spatial panel regression model, we predicted onion yields with the different weather conditions of the regions. We used the spatial auto regressive (SAR) model that reflects the spatial lag, and panel data of several climate variables for 13 main onion production areas from 2006 to 2015. The spatial weight matrix was considered for the model by the threshold value method and the nearest neighbor method, respectively. Autocorrelation was detected to be significant for the best fitted model using the nearest neighbor method. The random effects model was chosen by the Hausman test, and the significant climate variables of the model were the cumulative duration time of sunshine (January), the average relative humidity (April), the average minimum temperature (June), and the cumulative precipitation (November).

Near Future Projection of Extreme Temperature over CORDEX-East Asia Phase 2 Region Using the WRF Model Based on RCP Scenarios (RCP 시나리오 기반 WRF를 이용한 CORDEX-동아시아 2단계 지역의 가까운 미래 극한기온 변화 전망)

  • Seo, Ga-Yeong;Choi, Yeon-Woo;Ahn, Joong-Bae
    • Atmosphere
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    • v.29 no.5
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    • pp.585-597
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    • 2019
  • This study evaluates the performance of Weather Research and Forecasting (WRF) model in simulating temperature over the COordinated Regional climate Downscaling EXperiment-East Asia (CORDEX-EA) Phase 2 domain for the reference period (1981~2005), and assesses the changes in temperature and its extremes in the mid-21st century (2026~2050) under global warming based on Representative Concentration Pathway (RCP) scenarios. MPI-ESM-LR forced by two RCP scenarios (RCP2.6 and RCP8.5) is used as initial and lateral boundary conditions. Overall, WRF can capture the observed features of temperature distribution reflecting local topographic characteristic, despite some disagreement between the observed and simulated patterns. Basically, WRF shows a systematic cold bias in daily mean, minimum and maximum temperature over the entire domain. According to the future projections, summer and winter mean temperatures over East Asia will significantly increase in the mid-21st century. The mean temperature rise is expected to be greater in winter than in summer. In accordance with these results, summer (winter) is projected to begin earlier (later) in the future compared to the historical period. Furthermore, a rise in extreme temperatures shows a tendency to be greater in the future. The averages of daily minimum and maximum temperatures above 90 percentiles are likely to be intensified in the high-latitude, while hot days and hot nights tend to be more frequent in the low-latitude in the mid-21st century. Especially, East Asia would be suffered from strong increases in nocturnal temperature under future global warming.

An Analysis of Characteristic for Hydrologic Weather Parameters through the Various Statistical Methods (각종 통계학적 방법을 통한 주요 수문기상인자의 특성 분석 -서울지점을 중심으로-)

  • Lee, Jae-Joon;Kwak, Chang-Jae;Jang, Joo-Young
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.1245-1249
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    • 2009
  • 본 연구에서는 우리나라 수문기상인자의 특성변화 분석의 필요성을 지각하여 국내 기상관측소 중 관측년수가 30년 이상인 관측소 63개 지점에 대한 수문기상인자 중 연평균기온, 연평균상대습도, 연강수량, 연증발량, 연일조시간, 연강수계속시간, 연강수일수, 연적설일수, 연신적설일수 등의 자료를 수집하고 기본통계량에 해당하는 평균, 표준편차, 왜곡도, 변동계수를 통하여 수문기상인자의 경년적 변화를 파악하였다. 또한 각종 통계학적 기법을 이용하여 이들 수문기상인자의 경향성, 주기성, 변동성 등을 분석하였으며, 그 결과는 우리 나라를 대표할 수 있는 서울지점을 중심으로 정리하였다. 기본통계량을 분석한 결과 연강수량, 연강수일수, 연강수계속시간의 표준편차와 변동계수가 다른 수문기상인자 비해 상대적으로 큰 것으로 나타나 강수관련 인자들의 경년별 변화가 두드러짐을 알 수 있다. 또한 선형회귀분석과 5년 이동평균 결과 연강수량과 연평균기온은 증가, 연평균상대습도, 연일조시간, 연강수일수, 연증발량은 감소하는 경향을 보였다. Mann-Whitney Test, Wald-Wolfowitz Test, Hotelling-Pabst Test, Wavelet Method와 같은 통계학적기법으로 동질성, 독립성, 검정, 경향성 검정을 수행한 결과 연강수량, 연증발량, 연강수계속시간, 연강수일수, 연적설일수, 연신적설 일수 인자가 각각의 검정에서 동질성 및 독립성을 보였고, 경향성 검정에서는 연평균기온, 연평균상대습도, 연적설일수 인자가 신뢰수준 내에서 유의함을 보였고, 주기성 검정결과 본 연구에 채택한 9개의 수문기상인자들의 연속된 주기성은 나타나지 않았다.

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A study on the treatment of rhinitis by Sasang Constitutional Medicine (사상의학적(四象醫學的) 비염치료(鼻炎治療)에 관한 연구(硏究))

  • Park, Eun-kyung;Park, Seong-sik
    • Journal of Sasang Constitutional Medicine
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    • v.13 no.1
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    • pp.109-118
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    • 2001
  • 1. The purpose of this study This study was performed on the basis of clinical consideration about rhinitis patients who suffered from sneeze, rhinorrhea, rhinocleisis and etc. And we checked the clinical inclination of this disease and the characteristic treatments of Sasang Constitutional Medicine. 2. The method of this study For 17 months from October in 1999 to April in 2001 we selected outpatients who had consulted for rhinitis more than twice in the department of the Sasang Constitution of the Bundang Oriental medical hospital, Dongguk University, and 31 of those were confirmed of their course of treatment. From their medical records and history, we learned the general characterisics and patterns of rhinitis, and the qualities and effects of its various treatment. 3. The result of this study The result were as follows ; 1) The rate of patients who have had the symptoms over the two years was 74.2%. 2) In the distribution of chief symptoms, sneeze occupied 80.6% of all appealed symptoms, rhinocleisis 77.4%, rhinorrhea 71.0%, intranasal pruritus 54.8%, postnasal drip 16.1%, orderly. 3) The treatment period was about 30days. The method of treatment was the Herb-med Tx, acupuncture Tx and etc. The herb-med ingestion was about two times in that period. 4) On the effect of treatment, Sneeze and rhinocleisis were improved. 5) The symptoms of rhinitis was more depravated by fatigue and stressful condition than weather condition. This result shows that the improvement of general condition has an effect on the rhinitis treatment.

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Local Control and Remote Optimization for CSTR Wastewater Treatment Systems (CSTR 하.폐수처리장의 국지 제어 및 원격 최적화 시스템)

  • Bae, Hyeon;Seo, Hyun-Yong;Kim, Sung-Shin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.05a
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    • pp.21-25
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    • 2002
  • Activated sludge processes are widely used in biological wastewater treatment processes. The main motivation of this research is to develop an intelligent control strategy for activated sludge process (ASP). ASP is a complex and nonlinear dynamic system because of the characteristic of wastewater, the change in influent rate, weather conditions, and so on. The mathematical model of ASP also includes uncertainties which are ignored or not considered by process engineer or controller designer. The ASP model based on Matlab/Simulink is designed in this paper. The performance of the model is tested by IWA (International Water Association) and COST (European Cooperation in the filed of Scientific and Technical Research) data that include steady-state results during 14 days. In this paper, fuzzy logic control approach is applied to control the DO (dissolved oxygen) concentration. The fuzzy logic controller that includes two inputs and one output can adjust air flowrate. Also, this paper introduces the remote monitoring and control system that is applied for the CSTR (Continuously Stirred Tank Reactor) wastewater treatment system. The CSTR plant has a local control and the remote monitoring system which is contained communication parts which consist of LAN (Local Area Network) network and CDMA (Code Division Multiple Access) wireless module. Remote control and monitoring systems are constructed in the laboratory.

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Movement Monitoring System for Marine Buoy (해상 브이용 움직임 감시 시스템)

  • Oh, Jin Seok
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.2
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    • pp.311-317
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    • 2014
  • Buoy has different motion characteristics depends on the sea weather situations. The motion characteristics has an impact on antenna, solar power generation system and etc. installed within a buoy. Therefore, it is important to analyse motion characteristics for management and analyse the buoy conditions. This paper's Buoy motion monitoring system uses gyro sensor to detect motions of a light buoy, and the measured data transfers to the PC on the shore using signal processing algorithm. The aim of this research is to develop monitoring and management mechanism of a buoy by applying motion monitoring system. In this paper, the operation characteristic of movement monitoring system is verified through experiment. Further, in this paper, it can apply such as real-time visibility into the status of the buoy or many ocean facility's motion estimation of the future.

Geographical Distribution and Physical Structure of Gudle-jang Paddy-field in Cheongsando (청산도 구들장논의 분포와 물리적 구조에 관한 연구)

  • Cho, Young-Jae;You, Hag-Yeol;Yoon, Won-Keun;Choi, Sik-In;Lee, Young-Ok
    • Journal of Korean Society of Rural Planning
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    • v.18 no.3
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    • pp.103-110
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    • 2012
  • This study aims to find out the geographical distribution, the physical structure and characteristic of Gudle-jang Paddy-field in Cheongsando. On the basis of this study, the potential value and the assignment for the preservation of Gudle-jang Paddy-field were suggested. Gudle-jang Paddy-field is centrally distributed to Cheongsando and has various features as follows. First, it has the Ondol structure which is used Gudle-jang. Second, it has an irrigation canal which has functions of the tank and the prevention of cold-weather damage as well as the irrigation and drainage canal. The values of Gudle-jang Paddy-field are as follows; 1) It is the peculiar and inherent agricultural structure which is only found in Cheongsando. 2) It is the structure that the agricultural civil engineering and the agricultural water management technique of traditional methode are applied. 3) It has the worths of the traditional culture of Korea. 4) It is the important resource creating superb rural landscape of the region. In spite of these values of Gudle-jang Paddy-field, there were little efforts to preserve it. From now on, it is needed to form of sympathy about the value of Gudle-jang Paddy-field and to make efforts for preservation of it. Also the institutional and political strategy should be provided to preserve and manage Gudle-jang Paddy-field.

Changes in characteristic of weather elements in Nakdong River caused by climate change (기후변화로 인한 낙동강 유역의 기상요소 변동 특성)

  • Yang, Jeong-Seok;Lee, Jeong-Won;Jang, Woo-Joo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2012.05a
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    • pp.347-351
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    • 2012
  • 본 연구는 기후변화로 인한 국내 낙동강 유역의 기온, 강수, 상대습도의 변동 경향을 파악하고자, 낙동강 본류의 상, 중, 하류 지역을 연구대상 지역으로 선정하여 분석을 실시하였다. 이를 위하여 기상요소인 평균, 최저, 최고 기온과 상대습도 및 강우 자료를 기상청의 관측 자료를 활용하여 수집하였다. 분석을 실시함에 있어서 연평균, 최고, 최저 기온과 연평균, 최고, 최저 상대습도를 분석하였으며, 강우량 관측 자료를 통해 총 강우량, 강우집중률, 일 최대강우량을 고려하였다. 분석방법은 기후변화로 인한 기상자료의 변동 경향을 파악하기 위하여 비모수적 경향성 검정인 Mann-Kendall Test, Hotelling-Pabst Test, Sen's Test 3가지의 검정방법을 사용하였으며, 표준정규변량의 크기를 통하여 변동 경향의 유의성을 비교해보았다. 또한, 각 요소별 관측 자료의 상위 10개, 하위 10개의 자료를 통하여 최근(1995~2011)과 과거(1973~1994)의 기상요소들을 비교하여 변동 특성을 파악하였다. 연구지역 중 낙동강 중류 지점에 위치하는 구미의 경우, 요소별 자료 중 연평균기온의 상위 9개의 자료가 최근 17년 이내에 포함되어 있으며, 연 최저 및 최고 기온의 6개의 자료가 포함되어 있어 기후온난화가 진행되고 있음을 확인하였다. 연 최저 상대습도의 경우 3가지 경향성 검정 방법을 통하여 과거자료에 비해 하강하는 추세를 보이고 있다. 강우자료 분석 결과 관측이 시작된 이래 연강수량 중 상위 10개의 자료에서 7개가 최근에 발생한 것으로 분석되었고, 일 최대강우량은 9개가 포함되어 있다. 위의 요소별 분석 결과 낙동강 유역의 연강수량 및 강우강도는 대체적으로 증가하고, 기온 또한 증가하는 등 기후 변화로 인한 지구온난화현상이 국내에서도 나타나는 것을 확인 할 수 있었다.

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