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e-book 기상인자가 농업용 저수지 저수량에 미치는 영향연구

저자
김성준 ( Seong-joon ...
출판사
한국학술정보
발행일
2007.07.31
가격
전자책 : 3,000원
ISBN
ISSN
UCI
I410-ECN-0102-2018-500-003771680
The purpose of this paper is to analyze the relationship between meteorological factors and agricultural reservoir storage, and predict the reservoir storage by multiple regression equation selected by high correlated meteorological factors. Two agricultural reservoirs (Geumgwang and Gosam) located in the upsteam of Gongdo water level gauging station of Anseong-cheon watershed were selected. Monthly reservoir storage data and meteorological data in Suwon weather station of 21 years (1985-2005) were collected. Three cases of correlation (case 1: yearly mean, case 2: seasonal mean dividing a year into 3 periods, and case 3: lagging the reservoir storage from 1 month to 3 months under the condition of case 2) were examined using 8 meteorological factors (precipitation, mean/maximum/minimum temperature, relative humidity, sunshine hour, wind velocity and evaporation). From the correlation analysis, 4 high correlated meteorological factors were selected, and multiple regression was executed for each case. The determination coefficient (R2) of predicted reservoir storage for case 1 showed 0.45 and 0.49 for Geumgwang and Gosam reservoir respectively. The predicted reservoir storage for case 2 showed the highest R2 of 0.46 and 0.56 respectively in the period of April to June. The predicted reservoir storage for 1 month lag of case 3 showed the R2 of 0.68 and 0.85 respectively for the period of April to June. The results showed that the status of agricultural reservoir storage could be expressed with couple of meteorological factors. The prediction enhanced when the storage data are divided into periods rather than yearly mean and especially from the beginning time of paddy irrigation (April) to high decrease of reservoir storage (June) before Jangma.

e-book 계층분석적 의사결정기법을 이용한 비점원오염 관리지역의 선정

저자
신정범 ( Shin Jung B...
출판사
한국학술정보
발행일
2007.05.31
가격
전자책 : 4,000원
ISBN
ISSN
UCI
I410-ECN-0102-2018-500-003771675
This paper suggests a hierarchial method to select the target sites for the nonpoint source pollution management considering factors which reflect the interrelationships of significant outflow characteristics of nonpoint source pollution at given sites. The factors consist of land slope, delivery distance to the outlet, effective rainfall, impervious area ratio and soil loss. The weight of each factor was calculated by an analytic hierarchy process (AHP) algorithm and the resulting influencing index was defined from the sum of the product of each factor and its computed weight value. The higher index reflect the proposed target sites for nonpoint source pollution management. The proposed method was applied to the Baran HP#6 watershed, located southwest from Suwon city. The Agricultural Nonpoint Pollution Source (AGNPS) model was also applied to identify sites contributing significantly to the nonpoint source pollution loads from the watershed. The spatial correlation between the two results for sites was analyzed using Moran's I values. The I values were 0.38~0.45 for total nitrogen (T-N), and 0.15~0.22 for total phosphorus (T-P), respectively. The results showed that two independent estimates for sites within the test watershed were highly correlated, and that the proposed hierarchial method may be applied to select the target sites for nonpoint source pollution management.

e-book Development of Interactional Information Measuring Technique Usin...

저자
Lee Je-myung , Jung ...
출판사
한국학술정보
발행일
2007.05.31
가격
전자책 : 4,000원
ISBN
ISSN
UCI
I410-ECN-0102-2018-500-003771660
Defining the correlations between rural amenities, while difficult, is important for the adequate and efficient development of these amenities. In this research, an Interactional Information Measuring Technique(IIMT) using Information Gathering and Utilizing System(IGUS) was developed to objectively analyze the correlations between abstract ideas. In order to analyze correlations between rural amenities, this model used the Korean Dusan World Encyclopedia as IGUS and the relative interactional information was measured. The correlations between rural amenities were analyzed objectively using IIMT with the results satisfying the basic conditions of interactional information suggested in this research.

e-book A Production Method of Landslide Hazard Map by Combining Logistic...

저자
Lee Yong Joon , Park...
출판사
한국학술정보
발행일
2007.05.31
가격
전자책 : 4,000원
ISBN
ISSN
UCI
I410-ECN-0102-2018-500-003771655
The LRA (Logistic Regression Analysis) conducts a quantitative analysis by collecting a lot of samples and the AHP (Analytic Hierarchy Program) makes use of expert decision influenced by subjective judgment to a certain degree. This study is to suggest a combination method in mapping landslide hazard by giving equal weight for the result of LRA and AHP. Topographic factors (slope, aspect, elevation), soil drain, soil depth and land use were adopted to classify landslide hazard areas. The three methods (LRA, AHP, the combined approach) was applied to a 520 km2 region located in the middle of South Korea which have occurred 39 landslides during 1999 and 2003. The suggested method showed 58.9 % matching rate for the real landslide sites comparing with the classified areas of high-risk landslide while LRA and AHP showed 46.1 % and 48.7 % matching rates respectively. Further studies are recommended to find the optimal combining weight of LRA and AHP with more landslide data.

e-book Hydration, Strength and pH Properties of Porous Concrete Using Ri...

저자
Kim Young Ik , Sung ...
출판사
한국학술정보
발행일
2007.05.31
가격
전자책 : 4,000원
ISBN
ISSN
UCI
I410-ECN-0102-2018-500-003771640
This study was performed to evaluate void ratio, compressive and flexural strengths, and pH properties according to the content ratio of rice husk ash, aggregate size, and neutral treatment time of porous concrete with content of rice husk ash produced as an agricultural by-product. The SEM results for cement mortar with a 5% rice husk ash for the weight of cement formed more C-S-H hydrates due to the SiO2 of rice husk ash. In the XRD test, cement mortar with a 5% rice husk ash for the weight of cement registered a higher peak point of approximately =20~25° compared to cement mortar without rice husk ash. According to the results of the XRD and SEM tests, the SiO2 that was a major chemical element of rice husk ash generated a large amount of calcium hydroxide in the early stage of the hydration process of cement leading to the formation of ettringite. The void ratio of porous concrete with rice husk ash decreased with increasing content ratio of rice husk ash. In addition, the void ratio of porous concrete with rice husk ash decreased compared to porous concrete without rice husk ash. The compressive and flexural strength of porous concrete with a 5% and 10% content ratio of rice husk ash slightly increased compared to concrete without rice husk ash. The pH value of porous concrete rapidly decreased immediately after neutral treatment. Then, it gradually increased and decreased again after 14 days. However, the pH value was nearly the same regardless of neutral treatment time in 28 curing days. Also, for neutral treatment, the pH value of porous concrete showed appropriate pH levels (less than 9.5) in all mixtures for planting at 28 curing days.
The purpose of this study was to determine the optimum mix proportion of latex modified mortar for agricultural underwater concrete structures repair. The experimental variables included a latex and antiwashout admixture amount, binder-sand ratio, water-binder ratio. This study were evaluated a repair performance and environment effect of latex modified repair mortar for agricultural underwater concrete structures. The pH test was conducted to evaluated the environmental effect and the flow test was peformed to evaluated the workability. Also, compressive, flexural and bond tests were conducted. Test results show that the optimum mix proportion of latex modified repair mortar for agricultural underwater concrete structures, was achieved by 1:1.5 binder-sand ratio, 5% latex ratio (weight of binder), 1.3% antiwashout admixture ratio (weight of binder), 0.33 water-binder ratio and 10% silica fume replacement ratio (weight of cement). The environmental effect and repair performance of optimum mix proportion satisfied all target performance.

e-book Tracing March 2004 and December 2005 Heavy Snowfall of South Kore...

저자
Shin Hyung Jin , Par...
출판사
한국학술정보
발행일
2007.05.31
가격
전자책 : 4,000원
ISBN
ISSN
UCI
I410-ECN-0102-2018-500-003771620
This study is to grasp and analyse the temporal and spatial distribution of record-breaking heavy snowfall rarely occurred in the middle and southwest region of South Korea during March of 2004 and December of 2005 respectively. Snow cover area was extracted using the channels 1, 3 and 4 of NOAA AVHRR images and the snow depth distribution was spatially interpolated using snowfall data of meteorological stations. Using administration boundary and Digital Elevation Model from 1:5,000 NGIS digital map, the snowfall impact was assessed spatially and compared with the reports at that time. The damaged area by heavy snowfall over 15 cm snow depth could be identified successfully within the spatial extent of snowfall area extracted by NOAA AVHRR image.

e-book Fuzzy추론 시스템과 신경회로망을 결합한 하천유출량 예측

저자
허창환 ( Heo Chang-h...
출판사
한국학술정보
발행일
2007.05.31
가격
전자책 : 4,600원
ISBN
ISSN
UCI
I410-ECN-0102-2018-500-003771615
This study is aimed at the development of a runoff forecasting model by using the Fuzzy inference system and Neural Network model to solve the uncertainties occurring in the process of rainfall-runoff modeling and improve the modeling accuracy of the stream runoff forecasting. The Neuro-Fuzzy (NF) model were used in this study. The NF model, recently received a great deal of attention, improve the existing Neural Networks by the aid of the Fuzzy theory applied to each node. The study area is the downstreams of Naeseong-chun. Therefore, time-dependent data was obtained from the Wolpo water level gauging station. 11 and 2 out of total 13 flood events were selected for the training and testing set of model respectively. The schematic diagram method and the statistical analysis are conducted to evaluate the feasibility of rainfall-runoff modeling. The model accuracy was rapidly decreased as the forecasting time became longer. The NF model can give accurate runoff forecasts up to 4 hours ahead in standard above the Determination coefficient (R2) 0.7. In the comparison of the runoff forecasting using the NF and TANK models, characteristics of peak runoff in the TANK model was higher than ones in the NF models, but peak values of hydrograph in the NF models were similar.

e-book 빈도 분석법을 이용한 논벼의 한발 기준 10년 빈도 작물 증발산량 산...

저자
유승환 ( Yoo Seung-h...
출판사
한국학술정보
발행일
2007.05.31
가격
전자책 : 4,000원
ISBN
ISSN
UCI
I410-ECN-0102-2018-500-003771600
Estimation of crop consumptive use is a key term of agricultural water resource systems design and operation. The 10-year return period drought has special aspects as a reference period in design process of irrigation systems in terms of agricultural water demand analysis so that crop evapotranspiration (ETc) about the return period also has to be analyzed to assist understanding of crop water requirement of paddy rice. In this study, The ETc of 10-year return period drought was computed using frequency analysis by 54 meteorological stations. To find an optimal probability distribution, 8 types of probability distribution function were tested by three the goodness of fit tests including χ2 (Chi-Square), K-S (Kolmogorov-Smirnov) and PPCC (Probability Plot Correlation Coefficient). Optimal probability distribution function was selected the 2-parameter Log-Normal (LN2) distribution function among 8 distribution functions. Using the two selected distribution functions, the ETc of 10-year return period drought was estimated for 54 meteorological stations and compared with prior study results suggested by other researchers.

e-book 대규모 유역에서의 적정 용수이용량 산정

저자
류경식 ( Ryoo Kyong-...
출판사
한국학술정보
발행일
2007.05.31
가격
전자책 : 3,000원
ISBN
ISSN
UCI
I410-ECN-0102-2018-500-003771599
In general method to estimate the water supplies in the large-scale basin, indirect estimation method such as unit loading factor method has been used. However, the estimated water supplies are much different to the real water supplies used in the any basin because these general methods estimate them considering water supply demands only. Especially, water supplies for irrigation are big different to the real water supplies in which the water supplies for irrigation are depend on the weather conditions such as evaporation, basin conditions such as infiltration, the reservoir operation rule for irrigation water, and distribution methods. Thus, a new estimation method is developed to estimate the real water demands which is essential factors for the effective water resources operation in the basin. This method is for estimating the water supplies and return rates based on the survey of the irrigation reservoirs and the analysis of effects to the stream flows, return flows, and water supplies for irrigation which water supplies and return rates are used in the basin water management model. The water supply usages in each subbasin are validated by comparisons between the simulated discharges from the basin water management model and the discharges measured in the control points.