• Journal of The Korean Society of Agricultural Engineers
• /
• v.50 no.1
• /
• pp.95-106
• /
• 2008

Eco-friendly material and implementation methods have become important along with the existing standardized maintenance concept for the irrigation and flood control. However, the intrinsic function of the hydraulic structure is water supply and disaster prevention. Therefore, the material and work methods should be considered both eco-friendliness, durability and safety which are prerequisite elements to maintain the engineering function. In this study eco-friendly material and work methods would be classified into the vegetation based system, eco-friendly concrete system and stone-material system according to the characteristics of material. The quality standard for durability followed KS specification and related regulations. The quality standard for safety and eco-friendliness was set after literature review, and the database was developed using the standard. The structure applicable to onsite - the eco-friendly material and work method were classified based on the function and material of the hydraulic structure. Finally, database has been established for convenient management and selection of the proper material and work method. The eco-friendly material and work method could be searched easily for the convenience of the users, and the web-based data system has been developed for continuous registration of the material and work methods to be developed in the future.

• Journal of Korea Water Resources Association
• /
• v.31 no.4
• /
• pp.385-396
• /
• 1998

The south-western part of Korea is situated in an unbalance of water supply and demand relating to the Keum, Mankyung, Dongjin and Youngsan River and their estuary reservoirs. For example, the Keum River estuary reservoir is discharging the larger amount of yearly runoff into the sea due to the small storage capacity, while Saemankeum estuary reservoir which is under construction, has the smaller runoff comparing with its strorage capacity. And the downstream area of the Youngsan River, such as Youngkwang, Youngam are deficient in water due to larger demand and smaller supply. In order to solve the above unbalanced water supply and demand and also to improve the water use effciency, the Hierarchical Operation Model for Multi-reservoir System(HOMMS) has been developed and applied to analyze the multi-reservoir operation assuming that the above reservoirs were linked each other. The result of this study shows that $2,148{\times}106\;\textrm{m}^3$ of annual additional water requirement for agricultural and rural water demands are required in this region at 2011 of target year, and these demands can be resolved by diverting and reusing $1,913{\times}106\;\textrm{m}^3$ of the released water from the estuary reservoirs into the sea.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.53 no.4
• /
• pp.49-57
• /
• 2011

The objective of this study was to experimentally investigate the feasibility of SRI (system of rice intensification) in Korean rice farming. Eight experimental plots of $5{\times}15$ m in size were prepared on an existing rice field of loam soil. Spacing was $30{\times}15$ cm (conventional treatment: CT), $30{\times}30$ cm, $40{\times}40$ cm and $50{\times}50$ cm, respectively. CT were flooded and SRI plots irrigated intermittently 3 to 5 day interval during cultivation. Organic matter content and pH of the soil were $2.5{\pm}0.03$ % and $6.1{\times}0.2$, respectively, before the cultivation. The highest number of tillers and height of the plant were measured at $50{\times}50$ cm plots. The height and number of tillers and height in $50{\times}50$ cm plots were 10 cm and 1.5 times more than CT. Average irrigation supply to SRI and CT was 243.2 mm and 547.3 mm, respectively. It meant that the reduction of irrigation water in SRI plots over CT was estimated to 55.6 %. Therefore SRI was concluded to have a good enough possibility to be applied in South Korea because it was proven to be more effective in reduction of irrigation water and crop cultivation compare to the CT.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.56 no.6
• /
• pp.45-53
• /
• 2014

This study presents a system dynamics modeling approach to simulate daily streamflow in a watershed including wastewater treatment plant which contributes to irrigation water supply. The conceptual system dynamics model considering the complex and dynamic hydrological processes in the watershed was developed. The model was calibrated and validated each for two years based on observed flow data. Model performances in terms of $E_{NS}$, RSR, PBIAS, and $R^2$ were 0.64, 0.60, -3.6 %, and 0.64 for calibration period, and 0.66, 0.58, -2.6 %, and 0.66 for validation period, respectively, showing an applicability on generating the daily streamflow. System dynamics modeling approach could help better understand the hydrological behavior of the watershed being reused wastewater for agriculture, by providing graphical dynamics of the hydrological processes as well as conventional rainfall-runoff model results.

• Journal of Biosystems Engineering
• /
• v.42 no.4
• /
• pp.350-357
• /
• 2017

Purpose: In-situ monitoring of water quality is fundamental to most environmental applications. The high cost and long delays of conventional laboratory methods used to determine water quality, including on-site sampling and chemical analysis, have limited their use in efficiently managing water sources while preventing environmental pollution. The objective of this study was to develop an on-site water monitoring system consisting mainly of an Arduino board and a sensor array of multiple ion selective electrodes (ISEs) to measure the concentration of $NO_3$ ions. Methods: The developed system includes a combination of three ISEs, double-junction reference electrode, solution container, sampling system consisting of three pumps and solenoid valves, signal processing circuit, and an Arduino board for data acquisition and system control. Prior to each sample measurement, a two-point normalization method was applied for a sensitivity adjustment followed by an offset adjustment to minimize the potential drift that could occur during continuous measurement and standardize the response of multiple electrodes. To investigate its utility in on-site nitrate monitoring, the prototype was tested in a facility where drinking water was collected from a water supply source. Results: Differences in the electric potentials of the $NO_3$ ISEs between 10 and $100mg{\cdot}L^{-1}$ $NO_3$ concentration levels were nearly constant with negative sensitivities of 58 to 62 mV during the period of sample measurement, which is representative of a stable electrode response. The $NO_3$ concentrations determined by the ISEs were almost comparable to those obtained with standard instruments within 15% relative errors. Conclusions: The use of the developed on-site nitrate monitoring system based on automatic sampling and two-point normalization was feasible for detecting abrupt changes in nitrate concentration at various water supply sites, showing a maximum difference of $4.2mg{\cdot}L^{-1}$ from an actual concentration of $14mg{\cdot}L^{-1}$.

• Journal of Internet of Things and Convergence
• /
• v.9 no.6
• /
• pp.93-98
• /
• 2023

In paddy rice farming, water management is a critical task. To suppress weed emergence during the early stages of growth, fields are deeply flooded, and after transplantation, the water level is reduced to promote rooting and stimulate stem generation. Later, water is drained to prevent the production of sterile tillers. The adequacy of water supply is influenced by various factors such as field location, irrigation channels, soil conditions, and weather, requiring farmers to frequently check water levels and control the ingress and egress of water. This effort increases if the fields are scattered in remote locations. Automated irrigation systems have been considered to reduce labor and improve productivity. However, the net income from rice production in 2022 was about KRW 320,000/10a on average, making it financially unfeasible to implement high-cost devices or construct new infrastructure. This study focused on developing an IoT-Based irrigation valve that can be easily integrated into existing agricultural infrastructure without additional construction. The research was carried out in three main areas: Firstly, an irrigation valve was designed for quick and easy installation on existing agricultural pipes. Secondly, a power circuit was developed to connect a low-power Cat M1 communication modem with an Arduino Nano board for remote operation. Thirdly, a cloud-based platform was used to set up a server and database environment and create a web interface that users can easily access.

• Korean Journal of Soil Science and Fertilizer
• /
• v.45 no.6
• /
• pp.1173-1178
• /
• 2012

Water competition among domestic, industrial and agricultural sectors has been gradually heightened recently in Korea as the lack of water supply is expected in the near future. About 46% of nation's water use is consumed in paddy farming to produce rice. And the conservation of water resource and quality in agricultural sector is a pending issue in the nation's long term water management plan. New paddy rice farming techniques that use significantly less irrigation water are urgently required. System of Rice Intensification (SRI) that is now well known to produce more rice with less water consumption has not been tried in Korea yet. And environmental effect of SRI on greenhouse gases (GHGs) has not been well investigated. The objective of this study was to measure the effect of SRI on GHGs as well as water use and rice yield in a Korean paddy condition. Three experimental runoff plots $5{\times}15m$ in size were prepared at an existing paddy field. Runoff, GHGs emission and water quality were measured during the 2011 growing seasons while a Japonica rice variety was cultivated. Rice plants grew better and healthier in SRI plots than in continuously flooded (CF) and intermittently drained (ID) plots. Rice yield from SRI plots increased 112.8 (ID)~116.1 (CF)% compared with CF and ID plots. Irrigation requirement of SRI plots compared to CF plot reduced by 52.6% and ID plot reduced by 62.0%, meaning that about 37.9~47.4% of irrigation water could be saved. GHGs emission from SRI plots reduced by 71.8% compared to that from CF plot and by 18.4% compared to that from ID plot, meaning that SRI could help contribute to ease the greenhouse gas accumulation in the atmosphere. It was believed that SRI is a promising paddy farming technique that could increase rice yield, and reduce irrigation water requirement and GHGs emission not just in Korea but also other rice farming countries all over the world. However, it was recommended that long term studies under different conditions including rice variety, soil texture, water source, climate need to be conducted for reliable data for the development of environmental policies related to GHGs emission control and management.

• The Korean Journal of Franchise Management
• /
• v.2 no.2
• /
• pp.70-83
• /
• 2011

The number of agricultural products due to open in response to international competitiveness of the farming press and the need for structural adjustment in agriculture and in agricultural crops receive a fair market price, fair trade, such as improving efficiency sidaejeo appropriate response to the request of the government must have. For this purpose, compared to the communist bojaphan agricultural water efficiently changing the structure of the distribution, agricultural products originating from the acquisition phase choice of shipping a stable product supply and plans to expand production system to induce a smooth supply of agricultural products, expand processing capacity and sales control should be. Also, in the distribution process by eliminating various immoral conduct commerce retail establishment and enforcement of policies for efficient and accurate distribution statistics, information is needed. The ultimate goal of agricultural restructuring and ensure fair price for producers sangpuui and improvement of production facilities for maximizing and affordable for consumers, according to your preferences to receive the best offer will be Foo. Therefore, management increases the efficiency of just distribution costs, or margins, lowering the improvement is not practical to restructure the distribution structure of costs for the best product and must supply the next country of agricultural products, strengthen the consumer's purchase desire to meet will be.

• Journal of agriculture & life science
• /
• v.44 no.3
• /
• pp.99-110
• /
• 2010

This paper builds a system of indicators representing rural regional development level. Indicators were classified into two groups, that is, living environment indicator group and regional vitality indicator group. Living environment indicator group consists of four indicators including housing, road, water supply, and sewage system, while regional vitality indicator group consists of five indicators including regional economy, public finance, and demography. Real data of the year 2002 and 2006 were used to do the basic statistical analysis and estimate the suitable statistical distributions for each indicator. Data were applied for the three city/county type, general city, urban-rural combined city, and county. General cities have the strongest urbanization tendency among the three types, while counties have the weakest tendency. General cities turned out to be superior in housing condition, road density, water supply system and sewage system. Indicators of employment and local finance showed the highest levels in counties. The results of this analysis are expected to provide local governments with the appropriate reference for their rural regional development policy.

• Journal of Korea Water Resources Association
• /
• v.56 no.4
• /
• pp.245-259
• /
• 2023

The agricultural reservoir is a critical water supply system in South Korea, providing approximately 60% of the agricultural water demand. However, the reservoir faces several issues that jeopardize its efficient operation and management. To address this issues, we propose a novel deep-learning-based water level recognition model that uses CCTV image data to accurately estimate water levels in agricultural reservoirs. The model consists of three main parts: (1) dataset construction, (2) image segmentation using the U-Net algorithm, and (3) CCTV-based water level recognition using either CNN or ResNet. The model has been applied to two reservoirs G-reservoir and M-reservoir with observed CCTV image and water level time series data. The results show that the performance of the image segmentation model is superior, while the performance of the water level recognition model varies from 50 to 80% depending on water level classification criteria (i.e., classification guideline) and complexity of image data (i.e., variability of the image pixels). The performance of the model can be improved if more numbers of data can be collected.