Eumsung TM/TC system is composed of one control center, four reservoirs and twenty irrigation canal systems. In this paper we analyzed operation frequencies of the irrigation system to verify the effect of TM/TC system. Large facilities's operation frequency were more low then small thing and irrigation type was continuous irrigation. operation frequency was most high in may and june. usually water gate was operated once per 5-10 day. With these analysis we concluded that operators should operate irrigation facilities based on scientific technique and designer should make a proper choice in TM/TC system selection fit to the field.

There are two ways to mitigate the drought. One is the structural measures such as storage of irrigation water, development of emergency wells, etc. The other one is the nonstructural measures such as water saving management by the early warning system. To precast and evaluate the drought, we need to develop the drought indices for agriculture. In the present drought preparedness plans of Ministry of Agriculture and Forestry (MAF), it is prescribed that the preparedness levels should be classified by considering the precipitation, reservoir storage, soil moisture in paddy and upland, and the growing status of crops. However there are not clear quantitative criteria for consistent judgment. This shows that we have not selected and utilized the proper drought index for agriculture and we did not have the information system to calculate the drought indices periodically and warn the outbreak of the drought. The objectives of the study are to develope of Agricultural Drought Evaluation System and to evaluate this indices for current agricultural status using the system.

Instream flow is necessary to manage the basic function of the rivers. The evaluation method of instream flow in a big river has been studied widely, However, the study in a small river hasn't researched. In theses days the environmental function of a river becomes very important. The evaluation method and secure of instream flow are basic conditions to perform it. Especially view of stream, recreation, protection of ecology are highly demanded in a urban according to the multipurpose of river spaces. Methods for determining the instream flow in the stream were explored and examined through careful reviews and evaluations of available literatures. Development of the instream flow estimation method is based on the reviewed results and methods which can be used within the acceptable levels.

In 1998, Food and Agriculture Organization addressed that FAO Modified Penman method possibly overestimates consumptive use of water comparing to the measured reference crop evapotranspiration (PET) and Penman-Monteith method can be better choice for accurate PET estimation. Nevertheless it is still difficult to find research efforts about paddy rice crop coefficient for Penman-Monteith method. This study aims to estimate paddy rice crop coefficients for Penman-Monteith method. To estimate the crop coefficients, measured evapotranspiration data during 1982-1986 were used. The average Penman-Monteith crop coefficients for transplanted paddy rice were ranged in $0.78\;{\sim}\;1.58$.

In national prospective, the needs to develop water resources has been increased due to water shortage from diverse use of water resources in agricultural areas. Existing agricultural water demand, which has mainly been limited to the use of farming, are now expanding to diverse water uses such as supporting daily lives, diluting environmental pollution as well as industrial use for agricultural complex currently under construction in agricultural region. In this situation, for the sake of effective procurement of water resources and supply method, it is definitely required to enhance the effectiveness of budget investment and project proceedings through integrated re-development which links projects to strengthen existing dams, reservoirs and hydraulic facilities. The major scopes of this research includes developing different types of system such as selecting potential sites to re-construct reservoirs including generating base maps and thematic maps, data collection regarding water demands and reservoir status; analyzing reservoir data; estimating developable capacity and index calculation; and forecasting inundated areas. In addition, this study provides other products such as developing output generation system which can support wide use of data built and analyzed; database generation for better data management; data analysis including selection, extraction, indexation, and calculation of base items through standardization; data security system prohibiting exterior proliferation and malicious manufacturing of data.

Crop evapotranspiration rates of the garlic, potato and carrot were measured in a lysimeter at the National Institute of Subtropical Agriculture. The crop coefficients were calculated using the values of the actually measured evapotranspiration(ETcrop) and the reference crop evapotranspiration (ETo) estimated by the Penman-Monteith equation. The maximum crop coefficients of the garlic, potato, carrot and cabbage were 1.07, 1.07, 0.73 and 0.92 respectively. For the Citrus Aoshima Unshiu and Hallabong in the plastic house, the maximum crop coefficients were 1.38 and 1.29 respectively. Computer program using EXCEL was also developed to estimate the crop water use.

Rehabilitation and upgrading of the irrigation facilities are usually for the reservoirs, pumping stations, and other facilities in the paddy fields. Changes in food consumption patterns have taken place in Korea and there are growing foreign demands that we open our agricultural products market. In accordance with this situation, farmers are turning increasingly to growing vegetables which provide a high income cash crop. It is necessary to irrigate by pressure through pipe lines in farming facilities and mass production farming. Flood damage occurs as a result of heavy rainfall. The design criteria should be followed to minimize the risk of the flood damage in rehabilitation and upgrading.

Agricultural water is the main portion of water resources in Korea. And water loss of agricultural water is estimated 6% of all water resources. But studies and data for water loss aren't sufficient. We classified the agricultural water losses and measured the water losses in 6 experimental site. Measurements says that water losses ratio in main canal is 13.8%, water losses for distributing irrigation water is 31.1%. So, the total water losses is about 45%. But the water losses for distributing irrigation water is imperative factor for irrigation, So, it is not right that the water losses for distributing irrigation water is classified water losses and it is necessary to reclassify the agricultural water losses.

This study aims to evaluate applicability of AVHRR NDVI for drought prediction. Drought, one of the typical natural disasters, has damaged almost every year in different places and at time varied. An AVHRR satellite image can be a comprehensive tool to measure the drought because it is easy to obtain the vegetation status over the nationwide. This study explored a possibility of NOAA AVHRR NDVI applicability to drought because NDVI can provide plant vitality. Using May AVHRR imageries in 1998, 1999, and 2000, NDVIs are derived and compared with the rainfall amount to pursue the relationship between NDVI and drought. From the result, AVHRR NDVI showed a possible applicability in using drought prediction.

It is necessary to irrigate for agriculture in Korea and agricultural canals play important roles in irrigation. Nowadays gauging water discharge in canals is important because of water shortage in Korea. But It is rare to gauging water discharge in canals. Several water level gauges are installed in agricultural canals through TM/TC. But the abilities of the gauges are insufficient for agricultural water metering. In this situation, we are developing the water discharge metering system which is inexpensive and easy to maintain.

Agricultural water for rice growing is the important factor of water resources in Korea. so, it is imperative to know the practice of water management in paddy field. The experimental site has been operated in order to investigate water management practice and water supply discharge since 2001. There are 8 irrigation areas which are observed the water supply discharge in this site. We have investigate the water management practice in this site and we know that the practical date of rice growing stages and the date for calculating the water demand in paddy field. So, There is much differences between the calculated water demand and practical water supply. We could reduce the differences by calculating the water demand using the practical date of rice growing stages.

The purpose of this study are to insure flow rate for rural stream in the rural area. The analysis of drying stream characteristics for two streams(Bong-mu, Wang-jang stream) from field survey data. Also, a study area has been determined, and criteria of estimation has been established : criteria such as, available hydrological data, the size of stream lengths and basin areas and regional characteristics. The spacial analysis is applied to stream slopes for upstream and downstream at weirs, stream networks and ground water pump stations, sinuosity of drying stream. As a result of drying streams survey analysis, drying stream characteristics are followed; levee types are earth and natural, cross sectional shapes are trapezoid, stream bed materials are gravels and sands, facilities in streams are weirs. The cause of the reduction analyzed by investigation of the current status of facilities for agricultural water use. Agricultural reservoirs block up the stream and water does not flow over the reservoirs except by storm. They also discharge water through diversion channels and the water diverted does not flow through the natural stream. Farmers directly take water from the stream by weirs.

Many reservoirs have been constructed for sustainable utilization of water resources in Korea. Effective management of water resources in Korea becomes very important in resent years. Especially, the dredging in reservoirs is important for effective water resources management and one in easy water resources security methods. According to "The reservoir dredging mid-long term planning investigation report", it was investigated that 1221 reservoirs need to dredge among 3,288 reservoirs managed by KARICO. And, KARICO made a survey of reservoirs for the sediment and storage change in $2002{\sim}2004$. In results, it was investigated total storage $1,406{\pm}10^6m^3$, effective storage $1,344{\pm}10^6m^3$ in mid-small 2,748 reservoirs and the storage ratio decreased total storage ratio 15.7%, effective storage ratio 4.4%.

The water requirement of transplanting culture(TC) consisting of 16 plots and direct seeding culture in a well-drained paddy field(DC) also having 15 plots were measured in order to clarify the influence factors on water requirement. Each plot was maintained under different cultivation conditions. Those varied cultivation conditions were classified into 7 items. Subsequently, the relationship between water requirement and 7 items were analyzed by evaluating the average water requirement in each condition to clarify the items influencing water requirement. From the analysis of the results, the water requirement of DC was determined to be 3.5 times of the TC. Furthermore, water requirement in DC and TC were influenced mainly by ponding depth and locational condition respectively.

A Water Level gauge which composes a water supply system for water demand, information transmission system and the solar storehouse electromotive floodgate, regarding the structure plan and a production of the nothing power automatic floodgate it described. The important point must solve but urgently will compare the water amount used from system establishment place or not one. and It must give proof the efficient characteristic of system, must solve the technical problem portion against revision of the accuracy of upper downstream canal which is information transmission system of the Self-controlled check gate. The solar floodgate is more economic with the base which will reach and the system construction which is accurate.

This study was performed for the research on the method for reducing non-point pollutant with the gabion which was made of gravel-packed plastic frame, and for the characterization of gabion adsorbing pollutant. The result showed that the concentrations of suspended solid in turbid water were reduced to $77.7{\sim}84.7%$ when the water was flowing through the gabion. The uniformity coefficients on the grain size accumulation curves of the adsorbed pollutant were larger on the large grain size gabion than those on the small grain size gabion, and the coefficients of curvature were smaller on the large grain size gabion than those of the small grain size gabion. The adsorption rates were dependent on the grain size of packed gravel. The rates were smaller on inlet and outlet than those on middle place on the series of gabion.

High strength concretes utilizing EVA with micro particles were prepared by varying polymer/binder mass ratio and curing conditions with a constant water/binder mass ratio of 0.3. The EVA modified concretes on the compressive and flexural strength, microstructure, ultrapulse modulus in curing condition(dry and water curing) were studied. Also, scanning electron microscope analysis(SEM) was performed to reveal the presence of polymer film and cement hydrates in the concrete. The compressive strength of the EVA modified concretes cured at water conditions ere higher than that of the EVA modified concretes cured at dry conditions. But, the flexural strength of the specimens cured at dry conditions were higher than that of the specimens cured at water conditions. Due to the interaction of the cement hydrates and polymer film, an interpenetrating network originated in which the aggregates were embedded. The curing of the polymer modified concrete involves two step of cement hydrates and polymer modification, and cement hydrates was promoted in water conditions and polymer film formation take place when water evaporates and was thereby was favored in dry conditions. By SEM analysis, influences of polymer modification was strengthening of the transition zone between the aggregate and the paste, and the porosity of transition zone decreases. By spring analysis, it could known that polymer film affects in porosity decrease and strengthening of transition zone.

All concrete structure in agricultural improvement project must satisfied durability, serviceability, safety. It is important for structure that satisfied these natures to good quality at design and construction step, and must continuous maintenance. Most of the concrete structures is construct at winter season, is contacted with water, has various type and sporadic in wide area. The objective of this study is to make the Concrete-Quality-Control diagram for agricultural infrastructure project using GIS. And, analyze the diagram with external factor(terrain, stream, economic etc.) to know the factor of concrete quality control.

In this research, the physical properties of fresh concrete using lime stone powder as a part of cement were investigated. Fresh concrete using lime stone powder was prepared with various lime stone powder replacement($5{\sim}12$ volume %) for cement and the quantities of sand aggregate ratio in concrete were 47.3%, 48.5% and 49.4% of ratio of sand aggregate. The workability, flowing characteristics, air content and bleeding of concrete using lime stone powder were tested and the results were compared with those of ordinary portland cement concrete. In the experiment, we acquired satisfactory results at the point of fresh concrete characteristics using lime stone powder within the replacement ratio of $8{\sim}12%$ and the optimum quantity of sand aggregate ratio in concrete was found to be $48.5%{\sim}50%$ of ratio of sand aggregate.

Recently the existing environment-friendly method is used in irrigation and drainage canal. So, it is necessary that environment-friendly canal method which is stable and quality. Environment-friendly manufactures which were reflected demand characteristic of drainage and irrigation canal were developed. This study is focused on quality, stability for agricultural district development. According to the results, this method has quaility and economical efficiency, stability and natural characteristic, and will contribute to environment-friendly canal construction.

Prepacked polymer mortar that is mainly composed of MMA monomer and used for the patching and restoring materials of concrete structures was developed, and its hardening and strength properties were experimentally surveyed. Results of study show that the permeance of binder into the aggregate was excellent for the case of PMMA mixing ratio of below 10%, the surface hardening inferiority was not generated for the case of the ratio of over 5%. Working time of the prepacked polymer mortar and hardening shrinkage tended to decrease as the PMMA mixing ratio increased. On the other hand, the ratio turned out not to decisively affect on compressive and flexural strengths. Regardless of PMMA mixing content, the adhesive strength was about 2.5 MPa. Occurring the desquamation on the substrate of cement concrete showed the adhesive strength of MMA prepact polymer mortar was excellent.

EVA Powder modified high strength concretes were prepared by varying polymer/binder mass ratio with a constant water/binder mass ratio of 0.3. The effect of EVA powder on the slump, hydration heat, compressive and flexural strength, toughness and water absorption ratio was studied. In hydration heat test, temperature of hydration reaction displayed almost fixed level regardless of containing rate of EVA powder, but peak time of hydration reaction displayed late inclination as containing rate of powder increases. With the same water/binder mass ratio, the compressive strength and water absorption of EVA powder modified concretes decreased slightly when EVA powder was added and the flexural strength of EVA powder modified concretes rised slightly when EVA powder was added. Also, the toughness of the modified concretes can be improved markedly. The interpenetrating structure between the polymeric phase and cement hydrates formed at a $2{\sim}6%$(containing rate of EVA powder). The properties of the polymer modified concretes were influenced by the polymer film, cement hydrates and the combined structure between the organic and inorganic phases.

This study was performed to evaluate the strength and durability properties of recycled concrete containing water - redispersible copolymer powder(WRP) and blast furnace slag powder(BSP) [RCWS]. Material used were cemente, recycled coarse aggregare, natural fine aggregate, water-redispersible copolymer powder, blast-furnace slag powder. Especially, Water-redispersible powder was used for blending with Inorganic binders such as cemente, gypsum and hydrated lime etc. First of all, Mixed ratio method of RCWS made Two Type. One was called type-1 which used to BSP content 5% and WRP(Water-redispersible powder) content 0%, 1%, 2%, 3%, 4%, 5%, 6%. respectively. Another was called Type-2 which used to BSP(blast furnace slag powder)content 10% and WRP(Water-redispersible powder) content 0%, 1%, 2%, 3%, 4%, 5%, 6%. respectively. According to the experimental results of (RCWS), Incase Type-2 at curing age 28days, Compressive strength, pulse velocity and dynamic modulous of elasticity were shown higher than Type-1 and The more WRP content increasing($0%{\sim}6%$) was the lower Compressive strength, Pulse velocity and Dynamic modulous of elasticity. Water absorption ratio was in the range of $3.85%\;{\sim}\;3.23%$, it was almost equal to Type-1, 2 but Increasing the WRP content($0%{\sim}6%$), The water absorption ratio is decreased.

This study began to establish a risk evaluation method for irrigation reservoirs under the overtopping failure mode. To define the risk, reliability analysis was performed using time series of reservoir flood inflow and spillway outflow. The former was defined as a load and the latter was the resistance component. The method results in failure probability, which is calculated by convolution multiplication between probability distribution functions of both components. The proposed method was applied to 3 reservoir sites and each failure probability was determined as 0.0012, 0.00001, and 0.000001 respectively.

All these days, we achieved the result of our efforts on agricultural facilities by a huge budget for stable agricultural infrastructure development. But it is anticipated that the cost of maintenance is increased from now on since we've focused on installing facilities(agricultural infrastructures) in quantity more than in quality. Furthermore we are short of efficient management system(S/W) because of active and overall support for facilities expansion(H/W). This study is focus on how to improve our agricultural infrastructure for not only to maintain eco-friendly facilities but also to prepare water shortage era.

This study was attempted to provide some fundamental data for safety structrural design of biological production facility. Wind load and snow load, acting on agricultural structures is working more sensitive than any other load. Therefore, wind speed and snow depth according to return periods for design load estimation were calculated by frequency analysis using the weather data(maximum instantaneous wind speed, maximum wind speed, maximum depth of snow cover and fall) of 68 regions in Korea. Equations for estimating maximum instantaneous wind speed with maximum wind speed were developed for all, inland and seaside regions. The results were about the same as the current eqution in general. Design wind speed and snow depth according to return periods were calculated and Local design wind load and snow load depending on return periods were presented together with iso-wind speed and iso-snow depth maps. The calculated design snow depth by maximum depth of snow cover were higher than design snow depth by maximum depth of snow fall. Considering wind speed and snow depth, protected cultivation is very difficult in Ullungdo, Gangwon seaside and contiguity inland regions, and strong structural design is needed in the west-south seaside against wind speed, and structure design of biological production facility in these regions need special consideration.

It is design and manufacture which the rake operated in and out of water. Also irrigation test result of several times, the flux inside the waterway collects 0.15m/s to case below the dirt which is accumulated in the rake 30kg, difficulty was to examine closely the thing, it followed hereupon and the grade in the agriculture waterway flux inside the cursor waterway was quick, or, with water level in dirt removal it established in the irrigation facility downstream it will be able to increase a flux, very the possibility of getting an efficient power it is it knew.

The waste land can be changed to the land that creature can survive by the greening. The studies on the rooftop greening have increased rapidly in number since these studies have made a positive effect on the improvement of the urban ecosystem and the lacking greens environment of the city. However, the majority of research are for rooftop greening system of the public and commercial building. Therefore, the development of easily available rooftop greening system for private residences is required.

Experiments on the improvement in durability of pipe framework for plastic greenhouse were carried out. Effect of protection treatment such as primer and paint coating for new pipes and old rusted ones were evaluated by change of rusty degree and yield strength. The experiments have been conducted during five years until now but it was too short to find the clear differences. However, there was a little improvement in durability of greenhouse pipes by painting after removal of rust. And also component and corrosion characteristics of pipes being used in greenhouses were analyzed, and several countermeasures for protection from corrosion were reviewed.

The ginseng field structure collapses due to snow and wind. In order to study the structural modeling of ginseng field facility wind velocity test with shading material and strength test with used and unused timber were performed. The result of wind velocity test, we knew the characteristic of shading member of ginseng facility is followed linear regression, accurately. So, we made the assigned wind-value according to wind velocity. The result of strength test, the strength value of used-timber is smaller than the unused-timber and the coefficient of variance is larger than the unused-timber.

Pleurotus eryngii(King oyster) is one of the most promising mushrooms being produced on the domestic farms. The quality as well as quantity of Eryngii is sensitively affected by micro climate factors. To safely produce high-quality Eryngii all the year round, it is required that the environmental factors be carefully controlled by well designed structures equipped with various facilities and control systems. This study was carried out at the commercial mushroom cultivation houses to find out reasonable range of each environmental factor and yield together with economic and safe structures influencing on the optimal productivity of Eryngii. This experiment was conducted from Nov. 10, 2004 to Aug. 27, 2005 in Eryngii. cultivation houses. The environmental factors measured for this study were inside/outside temperature, relative humidity and $CO_2$ concentration in Pleurotus eryngii medium. In addition, the yield and quality of mushroom were made investigation. But the optimal productivity will be evaluated by considering the quality and quantity of mushroom production, energy requirements, facility construction and management cost, etc.

The solar energy floodgate which discusses will minimize a quotient bringing up for discussion friction resistance and it will do to write a disturbance power, with the base which will reach it will be able to use the solar power unit in order. It is a plan which to magnification supply the practicality and will give proof will the effort with the irrigation facility of the farming village. Magnification supply of the solar energy floodgate which it sees hazard the stack supervisor and the possibility the use against the farmer and the easy frost does the monitoring against and the work which it complements is necessary.

In paper the discrete optimum design program was developed using the continuous and discrete optimum algorithms based on the SUMT and genetic algorithms. In this paper, the objective function is the weight of structures and the constraints are limits state design limits method. The design variables are diameter and thick of steel pipe. Design examples are given to show the applicability of the optimum design using the continuous and discrete optimum algorithms based on the SUMT and genetic algorithms of this study.

It was convenient and the maintenance to do ease, to tilt the effort of one irrigation facility modernization by used to solar energy of reservoir flood gate and to reach and to lead in order to prepare one hand insufficiently it follows in leaving farming of the farming village and become older in age of the irrigation facility manager, it discussed one result. The reservoir flood gate which currently is developed but as improving the circular floodgate rain it does not measure the flow which is accurate is supplied from the reservoir it could not.

Uiryung Watershed area, located at the confluence of Nam River and Nagdong River has 9000 ha of agricultural land area and 3024 ha of paddy rice field have been reclaimed and managed by Korean Agricultural and Rural Infrastructure Corporation(KARICO) in the riparian area since 1954. In spite of irrigation and drainage improvement projects in last 3 decades since 1970, there are severe drought and innundation problems in the area. To improve the difficulties and efficient usage of irrigation water not only for agriculture but also for environmental conservation and cultural ceremony, Automatic Water management system has been installed supported by Ministry of Agriculture and Fishery in Korean Government. The control office in Uiryung Branch Office of KARICO, receive all the water management records from Remote Terminal Units in 7 reservoirs and 26 Pump stations to operate the decision supporting system of irrigation and drainage facility during cropping period. Since the completion of the water management system at the end of 2003, the electric cost decrease in 80 % than average years. In spite of decrease of two technical assistants since 2004, complains from farmers for the water management are very rare. The technological experience from the automatic water management system would contribute not only for the efficient water management of Uiryang area but also for the modernization of water management of other watershed areas in the future.

This study was carried out to find problems of the farmland according to the large scale land consolidation projects. Field ramp have problems such as steep slope, narrow width and the difficulty of entering into field and exiting from it. In case of the even ratio of the paddy plot, It showed that the difference of the maximum average level were 8.4cm for the general plots($0.3{\sim}0.4ha$), 12.6cm for the large scale plots($0.8{\sim}1.0ha$), and the level of outlet part was higher than the level of inlet part in some plots. Also, most of presently using inlets are closed and opened manually. It showed that farmers had difficult in the operating of the inlets or the outlets. So it is required the development of the suitable inlets and the suitable outlets.

A aggregate size distribution is an important in successful crop production in reclaimed tidelands. The aggregate size distribution for this study were determined of 0.1mm, 0.5mm, 1.0mm, and 2.0mm by wet sieving method. Agricultural activity, period of reclamation showed significant effects on aggregate size distribution in reclaimed tidelands. The percentage of <2mm aggregates for SMG, GHD, and SM reclaimed tidelands were ranged 8.9, 36.7, and 38.0%, respectively. The percentage of >0.1mm aggregates for SMG, GHD, and SM reclaimed tidelands were ranged 9.0, 26.0, and 48.9%, respectively.

This study aims to suggest an evaluation methodology of green-tourism potential for village level with amenity resources in rural areas. The amenity resources system was classified into three sub-classes(social, industrial, and natural/cultural/historical resources) and a relationship diagram between three classes and tourists' behavior was also defined. The methodology considers human resources in the village including the three sub-class amenity resources. The table and diagram were applied to make renewal plan for rural villages of the study area, Nami-myun, Keumsan-gun, Chungnam province, so that the development scheme for the villages was suggested reasonably by the new findings of this study.

There are positive evaluation as well as negative evaluation for Rural Industrial Park Project which was implemented since 1984 to boom up the regional economy in Korea. By conducting a survey for Rural Industrial Park enterprises located in Miryang-si, this study intends to examine the management condition of enterprises in Rural Industrial Parks and so derive the policy suggestion. According to the secondary data and the survey results, Rural Industrial Parks play an important role in the regional economy. The result of the survey shows that the enterprises are dissatisfied with excessively high distributing costs and they want improvement of roads and transportation condition. They recruit their employees mainly through advertisement and loan money from banks. One of serious problems is giving up the business due to shortage of fund or failing to find the markets. To prevent quitting business, a preliminary analysis of the feasibility of running business should be conducted. Technology and management guidance and marketing support are necessary not only for new enterprises, but for existing enterprises. Alternatives for connecting local resources and Rural Industrial Park and forming a network between local universities, institutes, and firms should be considered.

Doam watershed is located at alpine areas in the Kangwon province. The annual average precipitation, including snow accumulation during the winter, at the Doam watershed is significantly higher than other areas. Thus, pollutant laden runoff and sediment discharge from the alpine agricultural fields are causing water quality degradation at the Doam watershed. To estimate soil erosion from the agricultural fields, the Universal Soil Loss Equation (USLE) has been widely used because of its simplicity to use. The USLE rainfall erosivity (R) factor is responsible for impacts of rainfall on soil erosion. Thus, use of constant R factor for the Doam watershed cannot reflect variations in precipitation patterns, consequently soil erosion estimation. In the early spring at the Doam watershed, the stream flow increases because of snow melt, which results in erosion of loosened soil experiencing freezing and thaw during the winter. However, the USLE model cannot consider the impacts on soil erosion of freezing and thaw of the soil. Also, it cannot simulate temporal changes in USLE input parameters. Thus, the Soil and Water Assessment Tool (SWAT) model was investigated for its applicability to estimate soil erosion at the Doam watershed, instead of the widely used USLE model. The SWAT hydrology and erosion/sediment components were validated after calibration of the hydrologic component. The $R^2$ and Nash-Sutcliffe coefficient values are higher enough, thus it was found the SWAT model can be efficiently used to simulate hydrology and sediment yield at the Doam watershed. The effects of snow melt on SWAT estimated stream flow and sediment were investigated using long-term precipitation and temperature data at the Doam watershed. It was found significant amount of flow and sediment in the spring are contributed by melting snow accumulated during the winter. Thus, it is recommend that the SWAT model capable of simulating snow melt and long-term weather data needs to be used in estimating soil erosion at alpine agricultural land instead of the USLE model for successful soil erosion management at the Doam watershed.

In this stydy, the characteristics of the spatial location based on rural environment pollution facilities which can cause environmental pollution and thus lower the value of rural amenity was analyzed. This study showed that livestock feedlot occupied the highest percentage among the facilities analyzed and the size of facilities increased with increasing distance from the residential area. In addition, the facilities showed two typical characteristics in terms of their spatial distribution; uneven and even distribution which are characterized by concentrated distribution in a certain area and by scattered distribution in a wide area, respectively. As the facilities including livestock feedlot have a great potential to cause environmental problem such as air, water, soil and noise pollution, it is necessary to develop systematic plans for the management and improvement of the facilities.

The shape of a streamflow hydrograph is very much controlled by the area and depth of snow cover in mountain area. The purpose of this study is to suggest extraction methods for snow cover area and depth using NOAA/AVHRR images in Soyanggang watershed. Snow cover area maps ware derived form channel 1, 3, 4 images of NOAA/AVHRR based on threshold value. In order to extract snow cover depth, snow cover area maps were overlaid daily snow depth data form 7 meteorological observation stations. Snow cover area and depth was mapped for period of Dec. 2002 and Mar. 2003. For evaluating snowmelt changes, depletion curve was created using daily snow cover area in the same period. It is necessary to compare these results with observed data and check the applicability of the suggested method in snowmelt simulation.

The purpose of this study is to established a storage management method and operation standard for irrigation dams occupying the largest portion of small dams using storage management system. The system can be applied to seongju dam for effective management. The storage management method was established considering hydrology simulation and statistical analysis using the system. This method and operation standard are capable of analyzing additional available water, considering the water demand and supply of basin actually. It can improve the flood control capacity and water utilization efficiency by the flexible operation of storage space.

In this study, following works have been carried out : division of Nakdong River Basin into 25 sub basins, development of a technique to evaluate spatial distribution of rainfall and analysis of rainfall data of 169 stations, selection of control points, and selection of a hydrologic model(SSARR). The runoff analysis showed that the surface-subsurface separation and soil moisture index parameters are the most important two to the simulation result.

Initial mixing characteristics in near field regions were analyzed by FLOW-3D, for analyzing mixing behavior of submerged discharge from freshwater lake in sea water. FLOW-3D model was applied to the region near Geum-ho dike for its verification. Simulation results from FLOW-3D were compared to the observed data for the verification periods. FLOW-3D showed resonable prediction results compared to the observed data, except underestimation in area near outfall. Particularly, FLOW-3D showed a good prediction for movement of buoyancy jets. In addition, FLOW-3D model was applied to the region near Saemangeum dike, which is to be constructed in near future. It was expected that the results of model application to Saemangeum area could provide substantial information in planning submerged discharge facilities. Based on the model applications to Saemangeum area, it was recommended that outfall should be located to the distance which gave an enough depth of outfall from water surface.

In this study, following works have been carried out : division of Nakdong River Basin into 25 sub basins, development of a technique to evaluate spatial distribution of rainfall and analysis of rainfall data of 169 stations, selection of control points, and selection of a hydrologic model(SSARR). Analysis results were found that total volume of discharges at every control points have errors in a reasonable range, and the correlations between observed and calculated daily runoff discharges at every control points were well coincided.

The objective of this study is to check into variation trends of design rainfall according to change of the number of years for observed data. To make comparative study of the relation between design rainfall and recorded year, this study was used maximum rainfall for 24-hr consecutive duration at Gangneung, Seoul, Incheon, Chupungnyeong, Pohang, Daegu, Jeonju, Ulsan, Gwangju, Busan, Mokpo and Yeosu rainfall stations. The tests for Independence, Homogeneity and detection of outliers were used Wald-Wolfowitz's test, Mann-Whitney's test and Grubbs and Beck test respectively. To select appopriate distribution, the distribution of genaralized pareto(GPA), generalized extreme value(GEV), generalized logistic(GLO), lognormal and pearson type 3 distribution is judged by L-moment ratio diagram and Kolmogorov-Smirnov (K-S) test. Design rainfall was estimated by at-site frequency analysis using L-moments and Generalized extreme value(GEV) distribution according to change of the number of years for observed data. Through the comparative analysis for design rainfall induced by L-moments and GEV distribution, relationship between design rainfall and recorded year is provided.

In this study, SWAT model was applied to the Soyang Dam upstream watershed in order to evaluate the model applicability for estimating runoff, sediment, and nutrients loadings from the watershed. By trial and error method, the model parameters related with runoff, sediment, nitrogen and phosphorus were calibrated step by step. Then the simulated runoff, sediment, and nutrients loadings by the model were compared with the observed data measured at the Soyang Dam, the outlet of the watershed. And several statistical criteria were calculated to evaluate the model performance. From the comparison and statistical criteria, good agreement between simulated and observed stream flows was found. For sediment and nutrients, it was not reliable to quantitatively model the observed values, but the model could simulate the trend with reasonable accuracy. Hence, it was concluded that the model can be applied for the long-term non-point modeling in a large watershed.

The agricultural water demand that is calculated in present is difference with practical one by various situations in field. And, by various change, agricultural water demand can not estimate by agricultural land area simply. Considering various situations in field, calculated practical agricultural water demand and applied it to Korea Water Evaluation And Planing System (K-WEAP) in this study. The studied area is Seongju. The studied results showed that agricultural water demand calculate about 5.8 percent higher than existing one, and the agricultural water demand that is applied to K-WEAP calculate about $4{\sim}5.5$ percent higher. Total Agricultural water demand increased about 0.5 percent until 2011.

To trace the flood inundation area around rural small stream, RADARSAT image was applied because it has the ability of acquiring data during storm period irrespective of rain and cloud. For the storm of 9 August, 1998 in Anseong-cheon watershed, three temporal RADARSAT images before, just after and after the storm were used. After ortho-rectification using 5 m DEM, two methods of RGB composition and ratio were tried and found the inundated area in the tributary stream, Seonghwan-cheon and Hakseong-cheon. The inundated area had occurred at the joint area of two streams, thus the floodwater overflowed bounding discharge capacity of the stream. The progression of damage areas were stopped by the local road and farm road along the paddy.

Gates for the purpose of drainage are classified following the types of structure as: Radial Gate, Sluice Gate, Rolling Gate, Drum Gate. In many cases of the reclamation project the sluice type of gates are applied. Different from this general trend, however the radial type of gate was adopted in the Saemangeum project. In this case the discharge coefficients which are used for the sluice type of gate was applied. To estimate the correct amount of discharge which will be evacuated through the gates, therefore the proper discharge coefficients should be estimated before the operation of the gates. The discharge coefficients were estimated through the physical hydraulic modeling, and we got the results as: $0.72{\sim}0.84$ for the submerged condition on the both sides of upstream and downstream, $0.62{\sim}0.83$ for the free surface condition on the downtream side only, and $1.04{\sim}1.12$ for the free surface condition on the both sides of upstream and downstream. The discharge coefficients obtained from the experiments are greater than those of the sluice gates in the design criteria. From the results of the study we may expect that in the Saemangeum project the radial gates could evacuate larger amount of discharge than the originally designed discharge, so that we may sure that the Saemangeum gates have enough capability to control the evacuation of water not only in the usual period but also in the flooding season.

This study aimed to estimate applicability of a model to simulate circulation in estuarine lake caused by operation of drainage gates. The model consists of 2D (depth-averaged) hydrodynamic models, Delft3D-FLOW model and operation model for drainage gates. The flow through drainage gates was calculated using weir formulae with discharge coefficient, 0.8. The simulations are performed under two conditions: uncontrolled condition and controlled by periods of two days. The results on simulation of the model showed that the water level in estuarine lake was tend to increase above mean sea level. Therefore it was proved that the calibration and verification were needed in order to applicate this model for Saemankeum area.

This research evaluates agricultural water supply capabilities for water computing demand and supply for water of the whole water system of Ansung stream by carrying out basin water balance classified by irrigation facility of water system of Ansung stream.

This study considers that hydrologic stability evaluation of agricultural reservoirs designed by past standards and approximate increase methods of flood control when PMF(Probable maximum flood) flows in.

This study was performed for the analysis of the variation characteristics on riverbed according to the arrangement of stream. It was monitored of the variation progress of riverbed dependent on the elapsed time after the arrangement and It was studied that the hydraulic adjustment of the riverbed caused by the variation of the riverbed. The large amount of deposit just after the construction in which the riverbed was arranged to natural form was come from the reduction of flow rate by the installed artificialities such as weirs and stone weirs and by the stones or the concrete blocks attached to the stream sides of riverbanks. This phenomenon was well consistent with the usual characteristics that the accumulation is induced on upper stream of hydraulic artificialities and the erosion is induced on down stream of hydraulic artificialities. The large reduction of the deposit 1 year later after the construction showed that the riverbed eroded considerably because of the recovery of flow amount and the rise of flow rate.

본 연구에서는 조립토 다짐말뚝의 적용범위를 보다 연약한 지반에까지 폭넓게 활용하고자 하는 목적의 일환으로 등입도 콘크리트로 보강한 조립토 다짐말뚝공법의 적용가능성을 확인하였으며, 연구결과를 요약하면 다음과 같다. (1) 등입도 콘크리트에 대한 배합설계를 실시하고, 압축강도시험을 통한 강성 및 강도 특성의 규명과 변수위 투수시험을 통해 빈배합 콘크리트 공시체의 배수기능이 유지될 수 있음을 확인하였다. (2) 등입도 콘크리트에 대한 실내시험으로부터 도출된 강성 및 강도특성을 고려하고, 보강심도 및 치환율을 다향하게 가정한 조건하에서의 유한요소해석을 수행하여 각각의 조건에 따른 침하저감효과를 확인한 결과, 보강심도가 깊어지고 치환율이 커질수록 기존 조립도 다짐말뚝에 대한 침하억제효과가 커짐을 알 수 있었다. (3) 본 연구를 통해 등입도 콘크리트로 보강한 조립토 다짐말뚝의 적용가능성과 아울러 침하감소 효과를 파악하였으며, 기존 조립토 다짐말뚝의 침하량에 비해 보강심도, 치환율 등을 고려한 등입도 콘크리트로 보강된 조립토 다짐말뚝의 침하량이 억제되는 효과를 확인하였다. 향후에는 현장여건을 감안한 등입도 콘크리트의 다양한 배합비별 침하감소효과에 대한 규명과 함께 본 연구에서 제안된 공법의 현장적용성을 파악하기 위한 실물모형시험 또는 시험시공 등이 필요할 것으로 판단된다.

In this study, construction modulus, void ratio and settlement characteristics of 38 CFRD in domestic and foreign countries was investigated from monitoring data and the effect of field dry density and void ratio to dam body was analyzed. The standard void ratio of CFRD that can be easily used for dam designer and field engineer was proposed from the monitoring data. It was conformed that we can get the degree of compaction needed for reasonable compaction of dam body by calculating the field dry density from inverse operation of the standard void ratio. It was thought that the standard void ratio of CFRD is 0.2 as shape factor is under 4 and is 0.28 as shape factor is over 4.

In this study, settlement characteristics of 23 CFRD was investigated from monitoring data and the method to estimate the crest settlements considering internal settlement during constructions was proposed. Moreover, crest settlement smaller than 20cm and deflection of face slab smaller than 20cm are not considered to be critical to the stability of large dam whose height is over 40m. Therefore, we assigned the region as safe zone that can be used as a guideline of maintenance of dam. These estimated data can be used in the design, construction and long-term maintenance in domestic CFRD hereafter.

The properties of contaminants, contaminated soil, and the elapsed time are important factors to in-situ soil remediation. Gabr et. al. (1996) derived the solution equation of contaminant concentration ratio as initial one $(C/C_0)$ with time and spatial changes in contaminated area with vertical drains. The contaminant concentration ratio $(C/C_0)$ is analyzed with time and spatial changes as varying the effective diameter, porosity, shape factor, density of contaminated soil and temperature in ground and unit weight, viscosity of contaminants by using FLUSH1 model. Results from numerical analysis indicate that the most important factor to the in-situ soil remediation using vertical drains is the effective diameter of contaminated soil. It also shows that the viscosity of contaminants, porosity of soil, shape of soil, temperature in ground, unit weight of contaminants are, in order, affected to the soil remediation but density of soil is insignificant to the soil remediation.

Since most soils exist above the ground water table, negative pore pressure exist in unsaturated soils. Negative pore water pressure in unsaturated soil affects the soil structure and degree of saturation and it is important for accurate evaluation of unsaturate flow and behavior. This negative pore pressure is called a matric suction which causes an increased shear strength. Therefore, it is required that the effect of increase in the shear strength should be included in a geotechnical analysis. From the test result, the influence of net confining pressure and matric suction on the shear strength was analyzed and strength parameter was increased with matric suction increase and a unliner relationship was found to relate matric suction and shear strength.

In order to construct the farm road in Shi-Hwa project, coarse soils excavated from hillsides have been used as road materials for reclamation. Suitable borrow pits available in land are now limited and also they bring about environmental problems when soils are excavated at the borrow pits and transported to the site. When using fine and wet materials as fill, however, many engineering problems can be encountered. Usually, the materials have high water contents, low strength, and high compressibility. In order to use them, we need research that can improve the inherent properties of those materials. In order to tackle with the problems, researches on soil improvement involve mixing lime geo-cement to the fine wet soils. A lab model test is necessary to verify effectiveness and comparison of those techniques. A field test is also required to show applicability and to find problems that may exist in the design and construction stages.

In Korea, most landslides are occurred during the rainy season from June to September and have a shallow failure plane parallel to the slope. For these types of rainfall-induced failures, the most important factors triggering slope unstability is not the increase of pore water pressure but the decrease of the matric suction of unsaturated soils by rainfall infiltration. So it is essential to landslide hazard assessment that defines the characteristics of infiltration in natural slopes. In this study, field measurements have been carried out in order to monitor in-situ volumetric water contents and ground water table, at several depths and locations on a natural slope. The results show that rainfall infiltration is correlated with antecedent water contents, rainfall intensity and total rainfall. The ground water table was varied sensitively by every rainfall event.

In order to have compressive strength tests and frost heaving tests, two sorts of soil samples at Chonbuk-Do area were used. According to this research, the compressive strength of soil which was mixed by quick lime, was largely increased until 28 days but after 28 days, the increment of strength was seldom found and its maximum compressive strength increasing rate for content of quick lime was $10{\sim}15%$ scope. In the mixed rates of quick lime and briquette ash, the compressive strength of soil which was mixed by quick lime and briquette ash, was increased by increasing mixed rates of quick lime and its compressive strength was increased by additional quantity. The compressive strength of mixed soil within freezing-thawing 1 cycle was diminished around 30% compared to non-freezing soil's 28 days compressive strength but there were no movements after 2 cycle.

The research was performed to predict the potential landslide with roughness index. It was known that fractal dimension and surface area index can be represented the topography, specially when the natural slopes were rough or rugged. A test site was selected and fractal dimension and surface area index were calculated from the irregular triangle network. Fractal dimension were ranged between $2.016{\sim}2.046$ and surface area index $1.56E+07{\sim}2.59E+07$. Surface area index increased as fractal dimension increased. Slope stability was calculated by infinite slope stability analysis model and was compared to slope stability by fractal and surface area index. In the result, unsafe zones where slope stability is under 1.1 were $5.11{\sim}6.25%$ for the test site. It can be said that fractal dimension and surface area index are a good index to evaluate the slope stability because when fractal dimension and surface area index are greater, then stability of the site is more unsafe.

In order to treat flow problems for an unsaturated soils, it is required the mediation of the coefficient of permeability with variation of suction. The coefficient of permeability for soils can be determined by the direct or indirect methods. The direct methods of permeability can be performed either in the laboratory or in the field. The indirect methods can be predicted from the soil-water characteristics curve. Laboratory test methods to measure the coefficient of permeability can be categorized into two types, steady-state and unsteady-state. In this study, the coefficient of permeability for unsaturated soils was determined by the modified apparatus for steady state-method(Klute, 1972) and was predicted from the equations of Brooks and Corey(1964) and Van Genuchten(1980). Experimental results were compared with predicted coefficient of permeability and verified applicability of the two equations.

Slope angle, ground water table and thickness of soils are the key factors affecting landslide stability. However examining the factors such as thickness of soils; geological structure, slope angle, and height, in order to use the global landslide susceptibility forecasting analysis is very expensive and time consuming effort. So most researchers prefer to use the simplest methods such as the C strata and the USGS methods. In this research thickness of soils was calculated using these two methods and stability analysis was performed with the thickness of soils calculated by the two methods at the SINMAP based on ArcView 3.2. The two safety factor maps were compared with the past landslide records. The thickness of soils calculated by USGS method showed more unstable safety factors.

The reinforced concrete blocks for reinforced earth layer are combined with soil structures consisted of facing unit, reinforcing materials and soil. Those environmentally friendly facing units of reinforced concrete blocks are made of mine waste and tailing and that will be played a role of the effects of recycling use of wasted resources. The block are consisted of three types as curved or straight in order to control topography. The systems are also not limited to wall hight so that they are effectively used for protecting the slope of banking and cutting of earth works. The reinforced concrete blocks developed this time will be effectively applied for not only retaining wall, road, park, golf course, public office building constructions but also protecting of slope stabilization projects.

생물학적 통풍법은 유류오염 지역에 자주 적용되는 정화공법이다. 이 과정은 지중에 산소를 충분히 공급함으로서 토착 미생물에 의한 오염성분의 분해를 가능하게 한다. 따라서 이 공법의 적용시 공정진행에 따른 공법의 효율성 분석과 장기적인 정화효율 예측을 위한 지중 가스성분의 모니터링 시스템 도입이 매우 중요하다. 그러나 우리나라에서는 아직 그 적용사례가 보고된 바 없다. 따라서 본 연구에서는 현장에서 토양가스 성분의 변화를 모니터링할 수 있는 시스템을 개발하여 적용한 사례를 시스템의 구성과 측정방법, 관측결과를 중심으로 소개하였다. 현장적용 결과는 토양가스 모니터링 시스템은 운용 시작 후 6개월동안 센서나 측정장비에서 문제가 발생되지 않았으며, 공정관리를 위한 공법효율성 분석에 필요한 자료를 지속적으로 제공하고 있다.

The procedure of investigation and design of the soil contaminated with petroleum was introduced. Soil and water quality analyses were carried out to figure out the type of contaminants and the flume range according to the national regulation. In the investigation, it was verified that the soils in several dispersed locations were contaminated with petroleum. Therefore, in the design process, it was necessary to select a optimal remediation method after making the conception model of the site, and then the treatment method of incineration was selected.

If the load of constructing vehicles during the construction work acts on the road or the ground surface on the soft ground, due to the excess stresses in soils the trafficability of the vehicles influences the constructing efficiency, constructing period and so on. Stress distribution in soils is the very important element to design and to solve the problems of settlement, safety of foundations and trafficability of constructing vehicle in civil engineering. This research represents the comparative estimation of the actual and theoretical measurement on the underground stress of outer layer for each soil after the observation of each top soil layer for its vertical and horizontal stress in (1)homogeneous sand ground (2) weak stratum with the sand soil (3) weak stratum with gravel of the soil model, and it also investigates the effect of subsidence of ground by the repeated load. The underground stress turn out to be different in the value of theoretical and actual measurement after the trial examination of model.

This study attempts to develop indices in order to make an objective and effective evaluation of achievements in the first stage of operation of the Rural Village Development Project(RVDP) (the first 3 years of its operation). The results are as follows 1. Evaluation purposes are expansion of income-generating bases, improvement of living environments, strengthening of village's competence and establishment of an effective project's management system. 2. Evaluation items for the first three evaluation purposes, which are income-generating bases, improvement of living environments and strengthening of village's competence, are record of performance and substantiality in project's operation, results from operation, and capability in managing the project. Those for establishment of an effective project's management system are participation of habitants and the projects's management system. 3. As this study aims to develop the indices which can evaluate the state of operation in the interim of the project's operation and outcomes generated by then, the evaluation indices are selected by considering those criterions of representativeness, accessibility, usefulness and reliability. 4. As the indices developed in this study efficiency evaluate the process of project's operation and thus evaluate basically the project's operation on the basis of its efficiency. But, considering the purposes of the RVDP, it is included for the overall project's management system and plans for managing activities of the project to be evaluated on the basis of effectiveness.

The purpose of this study is to develop indices and a scoring method for effectively evaluating the project of rural well-longevity villages which makes up for insufficient parts of existing projects on improving settlement foundation and production environment. Evaluating indices include qualitative factors originated from the characteristics of the project so a scoring method based on an information measure technique is used for evaluating the results from each village. Evaluating indices are provided differently depending on each purpose for evaluation. Result indices can be used for ranking project villages and fundamental indices can be used to analyze villages elaborately to improve project plans.

As sustainable development and environment-friendly efforts in large-scale development projects emerge as major interests at home and abroad, man-made wetlands and eco-park facilities have been newly planned or created when developing reclamation districts recently. In this study, based on findings from a comprehensive review of relevant studies and planning cases, the basic direction and objectives of the plan were developed. A comprehensive analysis on the status of ecological environment and demographic and social environment showed that the planned site is in a process of migrating from early stages of reclamation to middle stages. It was planned for the eco-park to function as a major base along an ecological network consisting a freshwater lake and rivers and streams flowing into the lake in Hwaong District. Through a master plan and sectoral plans were planned according to desalination levels after reclamation. Then, habitats for livings organisms were also planned. The eco-park, the planned site, is also in a process of migrating from the early stages to middles stages. By creating an eco-park that considers post-reclamation ecological environment changes, natural succession processes will be preserved, which is expected to help local ecosystems to restore their functions on their own over a relatively long period of time and enable to observe the restoration process.

Effective information "query and retrieval" process is one of the fundamental problems in the field communication and information science and has become especially important due to dramatic increase in magnitude of information to be processed in modern era. Of particular importance at information exchange process, our study focuses on compositions of proper queries and retrieval of rural amenity resources. This particular task has been difficult because the rural amenity resources does not necessarily carry measurable traits and also contains huge amount of data. In this Letter, we propose an alternative approach to the architecture of the resource information system by use of a noble retrieval algorithm based on ontology. Test of efficiency and applicability of this new scheme was conducted, and it showed that this has possibility to be effective information retrieval process of rural amenity resources.

The purpose of this study is to develop a estimation model of migration with only population data using the cohort-survival model which has been used for forecasting future population. The fluctuation of population can be bisected to the natural change which can be occurred by birth and death and the social change which means migration. The factors of the social change are usually very important for establishing rural policies. However, researches using migration data has limitations because the usage of them are restricted. For verifying a estimation model of migration, comparing estimated population in 2000 year and migration quantity between 1996 and 2000 of 25 gu with real values, using population data and death ratio from 1995 to 2000 of the 25 gu in Seoul. Result shows a reliable data that R-square of forecating population model is 0.9755 and migration is 0.9180. So these model are worth to estimate a population and migration quantity to restricted migration data.

The purpose of this study is to classify rural villages through the amenity investigation by a village unit. PCA(Principal component analysis) is used for the classification of rural villages. The principal components of rural villages are deduced scale, population, infrastructure, traffic, education welfare and sightseeing by PCA.

The objective of this study was to ad dress concepts and classifications of rural amenity that has been issued in rural development. There are varieties of amenity concepts which are established not only in foreign countries but also in domestic. The concepts amenity have evolved several different aspects depends upon the societal situation and needs by the time goes on. In this paper, amenity concepts were explored and classified to find a suitable rural amenity concept to Korea so that the concept can provide a basic framework for the rural development and rural amenity resources uses.

The objective of this study is to make the development computer model of a rural village in EumSung-Gun, ChungChungbuk-do. The study district is ChoChon-Ri, WonNam-Myun, EunSung-Gun, and we investigated literature data and field survey in-site at the viewpoint of rural amenity of village unit. The procedure in this study is multi-variance analysis, extract the amenity of the village, make the developing direction, concept planning, and make a computer model.

A GIS-based integrated system for reuse of effluent from wastewater treatment plants was developed in this study. The GIS-supported program classified attribute data which the effluent's quantity and quality and agricultural thematic map data according to the 5 big river basin area. From the database, showing the spatial variation of the water quality of the effluent, thereby proposing proper mitigation strategies over the watershed. Also, this system enables the users who is going to reuse the reclaimed water for their paddies to provide of all the wastewater treatment plant data and agricultural structures and thematic map data.

Fallow paddy has been increased in disadvantageous farming condition area because of importation of foreign agricultural products, labor cost and the imbalance between farming cost and agricultural products price since 1990. The fallow paddy that has gradually increased needs to be prevented from the devastation by weed breeding for re-cultivation. In this study, two fallow paddies that manage with different water depth from the experimental field were selected for observation, and analysis of water quality, water balance and plant body change. The managed fallow paddy was more effective in water quality purification and plants growth control than non-managed fallow paddy. And the fallow paddy managed with a some degree water depth was the most effective field on weed control.

Organic compost has been widely applied to the cropland because it has been thought as Environmentally Sound Agriculture (ESA) in Korea. However, many field researches have been done to investigate water quality impacts of organic compost uses, compared to those from chemical fertilizer applications. It was found that pollutant loads from organic compost applied croplands were higher than those from chemical fertilizer applied areas. However, there might be other unknown factors affecting the results since the experiments were performed at the outside fields. In this study, indoor rainfall experiments using the Norton rainfall simulator systems were done to minimize and exclude errors from unknown sources by controlling soil characteristics, rainfall amount, rainfall intensity, and fertilizer treatments. The amounts of surface runoff and groundwater percolated from 10% and 20% slope plots were measured and water quality samples were collected and analyzed for BOD, COD, and T-P. Flow weighted mean concentration (FWMC) values were computed to assess effects of different fertilizer treatments. It was found that average concentration values of BOD were 5.57 mg/L from chemical fertilizer treated plot and 8.08 mg/L from organic compost treated plots. For 10% slope, FWMC BOD values from organic compost treated plots were higher by 29.9% than those from chemical fertilizer treated plots. For 20% slope, FWMC BOD values from organic plots were higher by 38.8% than those from chemical fertilizer plots. FWMC BOD values for 20% slope plots were higher than those from those for 10% slope plots. The similar trends were found for COD and T-P. In Korea, excessive use of organic compost has caused extremely high levels of organic matter contents at the cropland. Organic compost are usually applied to the cropland to improve soil quality, while chemical fertilizer is applied to help crop growth. Since organic compost is very slow in releasing its nutrients to the soil, farmers usually apply excessive organic compost for immediate effects and maximum crop yields, which has been causing soil and water quality degradations. Therefore, thorough investigations for better nutrient management plans are needed to develop the ESA strategy in Korea.

SWAT2000 model directly estimate the loading of water, and nutrients from land areas in a watershed. it allows to add nutrient loading from the point sourece like a sewage treatment plant and it also has a GIS interface which can easily see the spatial relationship between subbasins. For better assessment of nutrients loading to KEUMGANG estuary, SWAT2000 model applied to KEUMGANG estuary watershed. Model calibration and verification was firstly poerformed at Gongju site duing the period $1999{\sim}2003$. $R^2$ value was 0.96 for streamflow, 0.94 for T-N load and 0.52 for T-P load. The accuracy of the model at Gongju site suggest that the SWAT2000 can be available to estimate streamflow, Nutrients loading to the KEUMGANG estuary.

In order to assess the environmental risk of pesticides, information is usually required on the likelihood of exposure of organisms to the constituents of pesticides, expressed as a predicted environmental concentrations (PECs) and the likely effects of the constituents of pesticides on aquatic and terrestrial organisms, expressed as a predicted no-effect concentrations (PNECs). In this paper, the pesticide fate model, RICEWQ alone and coupled with the pesticide movement model, RIVWQ was used to simulate the potential for predicting the environmental concentrations of pesticides in paddy fields and adjacent surface water systems. The RICEWQ model was successfully calibrated against field data in poinding depth for paddy field. For the assessment of importance for water and pesticide management conditions and field scales, the integrated RICEWQ-RIVWQ model was simulated by the scenario analysis. The results of this study can be used as a basic information for assessing the environmental risk of pesticides.

Geumgang canal is planned to connect Geumgang lake with Saemangeum reservoir to accelerate desalinization and dillute polluted water in Saemangeum reservoir. The purpose of this study is to evaluate the variations of water quality by divesion of Geumgang lake flow to the Saemangeum reservoir. WASP5 model was used to estimate water quality concentration of Geumgang lake. Model calibration and verification was done for water quality data for 2001 and 2002. As a result of simulating water quality concentration for 4 scenarios, which was considered whether Geumgang canal will be built, there was little influence on water quality in Geumgang lake though Geumgang lake flow diverted to Saemangeum reservoir.

The objective of the study is to assess the water quality improvement resulted from the rearrangement of the irrigation water supply systems at Mankyeong River and Ansung Chun basin. There is a mixed type of watershed composed of urban and rural areas in the region. From the water quality analysis, showed high T-N, T-P concentration in Ansung chun and Mankyeong river caused by paddies separated widely around Ansung chun and Mankyeong river and by runoff of the pollution from the Ansung and Jeonju city. but the upstream of the river showed clean water quality, so if we use the upstream water as river maintenance water for water quality improvement, it is expected to be positive effect for rural environmental aspect.

Water Quality of effluent from wastewater treatment plants was reviewed to reuse effluent for agricultural water as alternative water resources. Among 2004, wastewater treatment plants, 19 plants are found to be used as wastewater resources applicable to irrigation. The total effluent capacities are 9,293 thousand $m^3$per day, which may be used to irrigate paddy fields. In order to know how much the effluent can be use for agricultural water, we classified the effluent according to the river basin area and evaluated the water quality of the effluent.

Recently reservoir is polluted by concentrative development of urbanization. Accordingly, the prediction of water quality has import meaning for protecting of water quality pollution. This study was carried out to predict water quality of Gyung Cheon reservoir by WASP5. We have established an integrated system on the basis of web, which predicts the future quality of water through water quality model, WASP5 based on information of water environment in a reservoir for agriculture, uniting expert system which supports the determination to set up measures for improving the quality of water to cope with the result.

The purpose of this study is the introduction of pollutant loads's estimation into Saemangeum watershed area with M.E.'s guidebook for TMDL and GIS tool. To estimate reliable pollutants loads, it is necessary to think about characteristic of removal, discharge and runoff as time series. In this study, it was calculated for generation loads which be came from pollutant source, discharge loads which be reduced in the treatment facilities and delivery loads which be considered the self purification parameter and delivery distance. To assess the delivery distance handily, it was particularly estimated using Arc-GIS. It was met with good results that delivery loads of BOD, T-N and T-P was reflected to seasonal precipitation. Lastly to verify the estimated pollutant loads, HSPF developed by USEPA was applied to it. It was showed a relativity of observed to simulated data for flow, Temperature, DO, BOD, $NO_3^--N$ TN and TP. Consequantly, this delivery loads can make full use of model input data for prediction of pollutant loads.

Large scale projects of sea-land reclamation have been practiced mainly to enlarge farmland in Korea. Most projects produced estuarine reservoir with dike construction, which might result in water quality problems due to block of natural flowing of stream water to the sea. Applicability of a widely accepted watershed-based water quality assessment tool (BASINS) and its associated watershed model was evaluated on the Hwaong watershed in Korea. BASINS was found to be a convenient and powerful tool for assessment of watershed characteristics, and provided various tools to delineate the watershed into land segments and river reaches, reclassify land use, and parameterize for HSPF simulation. WASP5 is a general purpose modeling system for assessing the fate and transport of conventional and toxic pollutants in surface water bodies. This study involved selection and linkage of available models to be used as a tool in evaluating the effects of BMPs for control on reservoir water quality. Overall,.Linkage of BASINS/HSPF and WASP5 was applicable and found to be a powerful tool in pollutant loading estimation from the watershed and reservoir, and its use is recommended.

This study was carried out to investigate characteristics of concentration of pollutants from paddy fields district with pumping station in Sumjin river basin. The size of paddy fields was 8.06 ha and the fields were irrigated from Nae-wol and Jum-chon pumping station. Total rainfall were 1,206.5 mm from June to December in 2004, and 922.0 mm from January to August in 2005. Total irrigation and drainage water were 1014.5 mm and 968.8 mm in 2004, 655.6 mm and 687.7 mm in 2005, respectively. The measured values of T-N of the irrigation water were ranged from 0.35 mg/L to 7.26 mg/L(average : 2.09 mg/L) and T-P were ranged 0.0486 mg/L to 0.4308 mg/L (average : 0.1583 mg/L). The values of T-N of drainage water were ranged from 0.30 mg/L to 20.31 mg/L(average : 2.99 mg/L) and T-P were ranged 0.1653 mg/L to 0.8847 mg/L (average : 0.3829 mg/L).

This study was conducted to identify the characteristics of non-point pollutants discharge in a small Rural watershed. For this purpose, the typical rural area in Gongju city was selected as a research site. Water quality and water quantity data in the stream and the precipitation of the watershed were analyzed periodically from May 1 to August 31 in 2005. Also, pollutant loads were estimated using these data. As a result, the mean concentrations of BOD, TN and TP in the stream were 3.16, 3.20, 0.236 mg/L rainy season and 0.93, 2.75, 0.058 mg/L in normal survey season respectively. The estimation of non-point pollutants discharge loads were shown that BOD was 5,154.2kg, T-N was 9,164.7kg, T-P was 308.4kg, and SS was 117,163.2kg from July to August. That means above of 90% of non-point pollutants discharge was occurred in rainy season.

The field scale experiment was performed to examine the effect of plant coverage on the constructed wetland performance and recommend the optimum development and management of macrophyte communities. Four sets(each set of 0.88ha) of wetland (0.8ha) and pond(0.08ha) systems were used. Water flowing into the Seokmoon estuarine reservoir from the Dangjin stream was pumped into wetland system. Water depth was maintained at $0.3{\sim}0.5m$ and hydraulic retention time was managed to about $2{\sim}5$ days; emergent plants were allowed to grow in the wetlands. After three growing seasons of the construction of wetlands, plant coverage was about 95%, even with no plantation, from bare soil surfaces at the initial stage. Dead vegetation affected nitrogen removal during winter because it is a source of organic carbon which is an essential parameter in denitrification. Biomass harvesting is not a realistic management option for most constructed wetland systems because it could only slightly increase the removal rate and provide a minor nitrogen removal pathway due to lack of organic carbon.

Land surface temperature (LST) for large areas can only be derived from surface-leaving radiation measured by satellite sensors. These measurements represent the integrated effect of the surface and are superior to point measurements on the ground, e.g. in Urban Heat Island. ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) is an imaging instrument that is flying on the NASA's Terra satellite launched in December 1999. ASTER acquires 14 spectral bands and can be used to obtain detailed datas of land surface temperature, emissivity, reflectance and elevation. Spatial resolution of 90m of TIR channels of ASTER is useful when we analyze the spatial variations of surface heat fluxes in urban areas. The purpose of this study is to extract the LST using ASTER TIR channels.

Land surface temperature(LST) is one of the key parameters in physics and meteorology of land-surface processes on regional and global scales. Urban Heat Island(UHI), a meteorological phenomenon by which the air temperature in an urban area increases beyond that in the suburbs, grows with the progress of urbanization. Satellite remote sensing has been expected to be effective for obtaining thermal information of the earth's surface with a high resolution. The main purpose of this study is to produce LST map of Cheongju and to analyze the spatial distributions of surface heat fluxes in urban areas. This study, taking Cheongju as the study area, aims to examine relationship between vegetation cover rates and surface temperature, and to clarify a method for calculation surface temperature with Landsat TM thermal images.

This study was performed to investigate the stream water quality characteristics according to the seasonal variation at Dowon-chon of the Dongjin river. Water samples were taken during 15 months from May in 2004 to July in 2005. The measured pH, EC of the stream water was ranged $6.49{\sim}7.22,\;21.0{\sim}173.4{\mu}S/cm$. The concentration of T-N, T-P, COD, SS, DO, BOD were $2.14{\sim}8.93mg/L$, $0.01{\sim}0.39mg/L,\;1.22{\sim}12.08mg/L,\;12.0{\sim}2,124.0mg/L,\;5.01{\sim}11.50mg/L,\;0.5{\sim}6.0mg/L$ respectively.

Natural environment of Weolgok-ri watershed has been well preserved as a traditional agricultural watershed. A year record of streamflow, $NO_3-N$, T-N and T-P concentrations data(Apr, 2004-Mar. 2005) was examined to estimate annual and seasonal patterns of pollutnat loads in streamflow and baseflow from the agriculture watershed. To estimate pollutant loads from baseflow, baseflow component from total stream flow was seperated using digital filter method in the Web-based Hydrograph Analysis Tool system. Loads of $NO_3-N$, T-N and T-P from streamflow and baseflow were evaluated to investigate pollutant loads contribution by baseflow. The $NO_3-N$, T-N, and T-P loads from streamflow were 13.85 kg/ha, 45.92 kg/ha and 1.887 kg/ha, respectively. $NO_3-N$, T-N and T-P loads from baseflow were 7.43 kg/ha, 24.70 kg/ha, 0.582 kg/ha, respectively. It was found that $NO_3-N$ and T-N loads were contributed by the baseflow(53% and 53% of Total-loads) than the direct runoff(47% and 47% of Total loads). However, only 30% of total T-P was contributed by the baseflow. It is recommended that one needs to assess pollutant load contribution by the baseflow to identify appropriate control strategies for effective watershed management.

Syngas or fuel gas production through biomass gasification is a century old technology. Biomass gasification is getting more and more interest recently as one of competitive renewable energy technologies. It does not contribute to increasing greenhouse gases(GHG). A down-draft gasifier was designed and tested for syngas quality using different fuel sets in this study. The gasifier was of about 100kW capacity. Tests were conducted at air flow rates ranging from 10 to $60m^3/hr$. Fuels tested included wood chips and wood char. The results showd that gas quality in terms of flammability was reasonably good when the temperatures were over $600^{\circ}C$ inside the gasifier. Although $800^{\circ}C$ or higher is recommended, gas quality was reasonably good. If insulation was provided outside the gasifier, the temperature would increase. When wood chips were used, the temperature was below $600^{\circ}C$ and gas quality was not good. It seemed that calorific values of fuel and height of reduction zone in the gasifier are very important. The results of the tests would provide important information for designing more improved gasifier and its operation.

Biogas is widely accepted as one of renewable energy. Raw biogas can be used in internal combustion engines either spark ignition or diesel engines. Since the gas has relatively low calorific values, engine power also is lower than rated power values. Modified engines or biogas-specific engines have been utilized in order to increase efficiency. Recently, gas engine/generators are provided for various purposes. They are mostly for LPG or natural gas. When biogas is fueled to the gas engines, de-rating is inevitable due to its lower calorific values. Meanwhile, massively produced commercial gas engines are more competitive in terms of initial investment for engines, compared to biogas-specific engines. Then, the characteristics of the commercial engine and power generation should be understood for better operation. A 5kW gas engine/generator(natural gas) was tested for determining an allowable maximum concentration of $CO_2$ in synthetic biogas, with respect to engine stating, power generation. Experimental results indicated that about 65% of methane concentration is required to start the gas engine. At this condition, the power generated was about 3 kW. It is about 60% of the nominal power, which is similar to the ratio of calorific values.

Biogas produced from anaerobic digestion processes has about 60% of methane and about 40% of carbon dioxide. Raw biogas can be used in internal combustion engines either spark ignition or diesel engines. Since the gas has relatively low calorific values, engine power also is lower than rated power values. Modified engines or biogas-specific engines have been utilized in order to increase efficiency. Another option is gas cleansing for increasing its calorific values. A couple of European countries adopted this approach in using biogas for one of transportation fuels, such as $CO_2$ scrubbing with water or special solutions. This study reports the results of water scrubbing for reducing $CO_2$ concentration. In 2.5m-high PVC pipe accepting water, $CO_2$ reduction rates were investigated. When flow rate of $CO_2$ and air mixture was about 5 LPM, $CO_2$ concentration was decreased up to 70%. Higher calorific biogas through water scrubbing is expected to be applied to various commercial engines without costly modification.

Runoff characteristics of organic matters and nutrients from greenhouse site in paddy field area were investigated during the irrigation period in 2004. The greenhouse selected which situated near the Nam river, Jinju, Korea used the ground water as the irrigation purpose. And, the rotating system of paddy field to upland was adapted as a cropping system which is a typical practice in this area. Various items such as total phosphorus(T-P), total nitrogen(T-N), dissolved oxygen(DO), BOD, etc. were observed to figure out the seasonal and spatial variation in the study sites. it was found that the risk of water pollution due to the contamination of nutrients in canals in green house sites, and their neighbouring small sized streams are much higher than those in ordinary paddy field areas. Further surveys and investigations are required to find out the counter measures to reduce water pollution occurred in greenhouse sites.

물리 화학적 원리에 의한 환경오염 정화방법은 종종 낮은 효율을 보이면서 공사비 부담은 큰 것으로 나타나고 있다. 그러나 생물학적 방법들은 이러한 단점들을 극복하면서 토양과 지하수를 정화할 수 있는 대안으로서 그 가능성을 입증하고 있는 실정이다. 그 중에서 생물학적 통풍법은 유류오염지역에 적용하고 있으며 그 원리는 지중 오염지역에 충분한 산소를 공급함으로서 오염성분이 토착 미생물에 의해 제거되도록 하는 것이다. 본 발표는 유류오염 지역에 적용된 생물학적 통풍법의 효율을 평가하여 제시하였다.

The object of this study was to presented regression equations for obtaining simply and quickly values of water quality items, BOD, COD, T-N, and T-P. Regression equations obtained to analyze relationships for water quality items to land use types in agricultural reservoir watersheds. In order to derive regression equations, a multiple linear regression analysis was used in this studying reservoirs. In this regression analysis, a independent values used land used types and dependent values used BOD, COD, T-N, T-P values in water quality items. The results showed that numbers of regression equation ranging above 0.90 in a multiple correlation coefficient (MCC) was not found, ranging from 0.70 to 0.90 in the MCC was 6, ranging from 0.40 to 0.70 in the MCC was 20, and ranging from 0.20 to 0.40 in the MCC was 4. The results of this study can be used as a basic information for evaluating simply and quickly water quality for proposing and designing steps in water quality policy.

It was monitored 3 years from 2003 to 2005 that the variational quality of water according to the arrangement toward natural shape of stream, and the variational characteristics of the each contents on water quality were analyzed after the separation into three periods of before, among and after arrangement construction. The quality monitoring results showed that the averages of water temperature, pH, DO, SS, BOD, T-N and T-P were $17.1{\sim}21.4^{\circ}C$, $6.44{\sim}7.74$, $7.02{\sim}8.36mg/L,\;0.7{\sim}51.9mg/L,\;0.310{\sim}1.044mg/L,\;0.41{\sim}2.43mg/L$ and $0.003{\sim}0.008mg/L$, respectively. The measured values of BOD, T-N and T-P were high just after construction, but the amounts were lowered as time passed, and finally stabilized in 2005. It ranged from 0.337 to 0.912 that the coefficients of correlation on linear regression between the discharges of water and BOD, T-N and T-P at each monitoring points, respectively.

Monitoring data from agricultural reservoirs throughout the country were analyzed to evaluate the limiting factor for algal growth and correlationship between Chl-a, total phosphorus (TP), total nitrogen (TN), and chemical oxygen demand (COD). It was used for the analysis to monitored data of 394 reservoirs such as TP, TN, Chl-a, and COD from 1999 to 2003. This study analyzed water quality items in terms of areas, seasons. It turned out that phosphorus in agricultural reservoirs (about 80%) was dominant limiting factor for algal growth. Therefor, it appears that the appropriate managements of phosphorus in the agricultural watershed are crucial to prevent excessive on algal growth. Generally, there is correlation between Chl-a and TP while Chl-a do not have effect on TN. Also, Chl-a have influence on COD. This study could be used beneficially for water quality management of agricultural reservoirs and related water quality modeling.

Accelerated soil erosion is a worldwide problem because of its economic and environmental impacts. To effectively estimate soil erosion and to establish soil erosion management plans, many computer models have been developed and used. The Revised Universal Soil Loss Equation (RUSLE) has been used in many countries, and input parameter data for RUSLE have been well established over the years. However, the RUSLE cannot be used to estimate the sediment yield for a watershed. Thus, the GIS-based Sediment Assessment Tool for Effective Erosion Control (SATEEC) was developed to estimate soil loss and sediment yield for any location within a watershed using the RUSLE and a spatially distributed sediment delivery ratio. SATEEC was enhanced in this study by developing new modules to:1) simulate the effects of sediment retention basins on the receiving water bodies, 2) prepare input parameters for the Web-based sediment decision support system using a GIS interface. This easy-to-operate SATEEC system can be used to identify areas vulnerable to soil loss and to develop efficient soil erosion management plans.

The objective of this study is to evaluate design parameters of free water surface constructed wetland for the reduction of agricultural nonpoint source pollution. From literature review, the key design parameters were selected as influent concentration, influent water volume, hydraulic retention time and wetland system arrangement. The design value for each parameter was established after pilot study. Full-scale constructed wetland on the basis of the designed values was constructed to evaluate those reasonableness. The results of this study showed that the designed values for free water surface constructed wetland were appropriate for the reduction of agricultural nonpoint source pollution.

The objective of this paper is to analyze the environmental effects by the fertilizer change with wastewater reuse for agriculture. For this research, Lysimeter tests are being implemented to cultivate rice with different levels of fertilizer applications with wastewater irrigation., and to analyze the nutrient loading by wastwater reuse in paddy fields was examined the CREAMS-PADDY model. CREAMS-PADDY model is modified from CREAMS model for considering the hydrologic cycles in paddy field. As a result, in the lysimeter treated by irrigation with wastewater and chemical fertilizer with half of the conventional amount showed generally similar tendency to the control plot. This may require the modifications of standard cultural practices for rice in terms of fertilizer and pesticide applications. However, high concentration of sodium in wastewater might cause damage to physico-chemical properties of paddy soil. And the wastewater reuse effects on nutrient loads were quantitatively analyzed and this results provide the reasonable management for agricultural reuse.

This study proposes a particular approach to assess information about NDVI(Normalized Difference Vegetation Index) and LAI(Leaf Area Index) from the spectroradiometer and NOAA/AVHRR satellite data. AVHRR data were collected in twelves months over a one year period in 2004. We calculated 10-day composite NDVI using daily composite AVHRR surface reflectance products(1km spatial resolution). The 10-day composite NDVI have a great effect on the plant growth conditions. Considerably, NDVI was increased by developing muscle fiber tissue from April to May. Then the NDVI increased until the August and then decreased until February. The highest month was at August and the lower month was at December. The difference NDVI analysis using December and another months data was conducted, the results were provided information on the variation of vegetation coverage. The result suggest that a relationship established between the LAI and NDVI in 2004.

This study was carried out to evaluate of water purification in oxidation pond with filamentous algae mat. It is the water treatment process in the small rural streams to remove the organic materials and nutrients. We used the filamentous algae mat(FAM) which selectively predominate the filamentous algae to prevent the additional contamination by algae outflow. The removal efficiencies of COD, SS, T-N and T-P in Oxidation Pond with Filamentous Algae Mat were -2.5%, 84.7%, 63.9% and 89.2%, respectively. The removal efficiencies of T-N and T-P which are nutrients index were high. Results of this study would help us to determine the possibility of using the water treatment on the contaminated small rural streams.

Wastewater reuse are exposed public health risk by pathogens. Therefore, this study was examined for microbial risk assessment after irrigation as treated wastewater in paddy rice plots. Five treatments were used: biofilter effluent, UV disinfected water, pond treatment, wetland treatment and conventional irrigation water. Risk assessment was calculated based on the beta-Poisson model by concentration of E. coli from 2003 to 2005. Monte-Carlo simulation (n=10,000) was used to estimate the risk characterization of uncertainty. The risk range was from $10^{-5}$ to $10^{-8}$ except biofilter effluent was $10^{-4}$ in June. The USEPA(1992) has recommended that risk of < $10^{-4}$ is acceptable level of safety for potable waters. In 2005, risk value was lower than 2003, 2004 because of the first irrigation for plowing water is lower E. coli concentration used tap water. It is shown that the first irrigation water quality was important for wastewater irrigation in paddy. UV disinfection and natural treatment used pond and wetland were thought to be an effective for wastewater reuse.

The objective of the study is to investigate the application of the mid-range model for agricultural ungaged small watershed. In this study, the need for the selection of an optimal model was presented, and the Feasibility of the GWLF(Generalized Watershed Loading Function) model was examined for agricultural small watershed. The study watershed covers 384ha, and the hydrologic and water quality data were monitored from 1996 to 2004. In the results of the simulation for the calibration period $(1996{\sim}1999)$ and verification $(2002{\sim}2004)$, $R^2$ were $0.70{\sim}0.91$ and RMSE was $2.11{\sim}5.71$. Then, the results of water quality simulation for SS, TN and TP, show that $R^2$ were 0.58, 0.47 and 0.62 respectively. This results were compared with the other research using the detailed models (SWAT, HSPF) for the same watershed and this showed the feasibility of mid-range model for the small watershed.

The objective of this paper is to develop the microorganism concentration simulation model for the health related effect analysis while farmers and water managers reuse the wastewater for agricultural irrigation. This model consists of the CE-QUAL-R1 model and the CREAMS-PADDY model. The CE-QUAL-R1 model is the 1-D numerical model to analyze the water quality of the reservoir and the CREAMS-PADDY model is modified from CREAMS model for considering the hydrologic cycles in paddy field. This model was applied to examine the application by the observed data from 2003 in Byoungjum study area. From this research, the average root mean square error (RMSE) for the simulated concentration during the calibration period was 0.51 MPN/100ml and correlation coefficient $(R^2)$ was 0.71. And the RMSE for the simulated concentration during the verification period was 0.46 MPN/100ml and $R^2$ was 0.73. This simulation results show that the coliform inflow concentrations by the wastewater irrigation wield great influence upon the temporal coliform concentrations in paddy field.

In Korea, water management policy had been successfully conducted until late 1980's. During the period, fundamental needs of human-being, such as requirements of drinking and irrigation waters and flood protection for living, had been satisfied. However, most of recent water problems occurred after the late 1980's such as water quality management and new water resources development, have been unresolved and accumulated. Because, our water governing institutions have become ineffective as water management issue has been changed gradually from fundamental human needs such as water supply and/or flood protection to complex/integrated issues, for example, river restoration. To solve those water problems accumulated, we needs a new paradigm of water governing institution such as setting up national water management committee and river basin committee, in order to coordinate water-related ministries' policies and establish national water resources planning in an integrated format.

Many computational models using computer program in agricultural engineering were proposed and introduced until now. These programs were developed based on procedure and structural program paradigm, so it's hard to reuse because programs become bigger and complex. In this study proposals a program paradigm that is easy to combine and reuse. Embedded engineering techniques are Java, JavaBean model, object-oriented programming.

It is necessary that the construction of submerged breakwater could minimize and compensate the negative effect on the marine environment and ecosystem caused by the Saemangeum reclamation. The important merit of this proposal is that the space between Saemangeum embankment and submerged breakwater is expected to become nursery ground for fish and shellfishes. The purpose of this study was investigated hydraulic characteristic of submerged breakwater to investigate the possibility of mitigation in the fisheries ground by hydraulic experiment.

Propriety of PERT network for planning and management in large-scale systems was investigated. We also review the example of small and middle size system to compare the appropriateness of PERT analysis method. For comparing the appropriateness of PERT analysis method the calculation time, and the variances were estimated. Eventualy, we proposed the criteria of PERT analysis method for planning and management large-scale systems.