• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.246-251
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• 2001

This study is aimed to develop system that can export height automatically with Hierarchical Delaunay Triangulation and finally provide profile of hydraulic channel using 3D terrain geometry model. In this study, by using the object-oriented technique, we developed the traverse and cross-section design system of agricultural facilities, which maintain a consistency in the irrigation design process. This system can design the traverse and cross-section profile for the line type facilities. The results of this study, as for the design based on geography, after carrying out the modeling by using TIN of which employs Delaunays algorithm, it was found that the latitudinal design of the facility is feasible. And, as for the formulation of TIN, we obtained more precise result from using contour, stream, and road data rather than using the contour by itself.

• 한국농공학회지
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• 제13권4호
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• pp.2471-2478
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• 1971

Go Cong Water Control Project was conducted on its preliminary survey and design by Agricultural development Corporation for the Korean Government, an Executing Agency, and Directorate of Irrigation and Rural Engineering of the Ministry of Land Reform, Agriculture and Fishery Development for the Vietnamese Government, a cooperation Agency, under Korean and Vietnamese Economic and Technical Cooperation Program. The main purposes of the project are aimed at the improvements of irrigation and drainage, and salt water prevention of the Go Cong area located at northern part of the Mekong Delta. All the works from field survey through design to preparing reports were carried out by ADC alone and recently Korean Government submitted the relevant reports to vietnamese Government through official channel. The contents of the project are summarized as following: 1. The project comprises irrigation, drainage and salt water prevention facilities on the benefited area of about 55,000 hectares, covering Go Cong and Dinh Tuong(My Tho) Provinces and it will be possible to cultivate rice cropping twice a year, irrigating all the area in the dry season; 2. With completion of this project, annual production of rough rice and vegetables are anticipated to increase by 222,600 .T. and 142,600 M.T. respectively and the internal rateof return stants at 26 per cent, applying for the exchange rate of US $ 1 to VN $ 275. 3. Total investments required for the project are estimated at US $ 56,394,000 of which actual construction cost is estimated at US $ 39,183,000. The project has planned to be d to be developed by four stages, taking bout 7 years. 4. The project needs for three places of pumping plants. 57Km of feed and main irrigation canals, 81Km of drainage channels, 97Km of dike, 23 places of sluices and navigation locks, etc.

• 한국농공학회지
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• 제16권1호
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• pp.3225-3262
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• 1974

The purposes of this thesis are to clarify experimentally the variation of ground water temperature in tube wells during the irrigation period of paddy rice, and the effect of ground water irrigation on the growth, grain yield and yield components of the rice plant, and, furthermore, when and why the plant is most liable to be damaged by ground water, and also to find out the effective ground water irrigation methods. The results obtained in this experiment are as follows; 1. The temperature of ground water in tube wells varies according to the location, year, and the depth of the well. The average temperatures of ground water in a tubewells, 6.3m, 8.0m deep are $14.5^{\circ}C$ and $13.1^{\circ}C$, respercively, during the irrigation period of paddy rice (From the middle of June to the end of September). In the former the temperature rises continuously from $12.3^{\circ}C$ to 16.4$^{\circ}C$ and in the latter from $12.4^{\circ}C$ to $13.8^{\circ}C$ during the same period. These temperatures are approximately the same value as the estimated temperatures. The temperature difference between the ground water and the surface water is approximately $11^{\circ}C$. 2. The results obtained from the analysis of the water quality of the "Seoho" reservoir and that of water from the tube well show that the pH values of the ground water and the surface water are 6.35 and 6.00, respectively, and inorganic components such as N, PO4, Na, Cl, SiO2 and Ca are contained more in the ground water than in the surface water while K, SO4, Fe and Mg are contained less in the ground water. 3. The response of growth, yield and yield components of paddy rice to ground water irrigation are as follows; (l) Using ground water irrigation during the watered rice nursery period(seeding date: 30 April, 1970), the chracteristics of a young rice plant, such as plant height, number of leaves, and number of tillers are inferior to those of young rice plants irrigated with surface water during the same period. (2) In cases where ground water and surface water are supplied separately by the gravity flow method, it is found that ground water irrigation to the rice plant delays the stage at which there is a maximum increase in the number of tillers by 6 days. (3) At the tillering stage of rice plant just after transplanting, the effect of ground water irrigation on the increase in the number of tillers is better, compared with the method of supplying surface water throughout the whole irrigation period. Conversely, the number of tillers is decreased by ground water irrigation at the reproductive stage. Plant height is extremely restrained by ground water irrigation. (4) Heading date is clearly delayed by the ground water irrigation when it is practised during the growth stages or at the reproductive stage only. (5) The heading date of rice plants is slightly delayed by irrigation with the gravity flow method as compared with the standing water method. (6) The response of yield and of yield components of rice to ground water irrigation are as follows: \circled1 When ground water irrigation is practised during the growth stages and the reproductive stage, the culm length of the rice plant is reduced by 11 percent and 8 percent, respectively, when compared with the surface water irrigation used throughout all the growth stages. \circled2 Panicle length is found to be the longest on the test plot in which ground water irrigation is practised at the tillering stage. A similar tendency as that seen in the culm length is observed on other test plots. \circled3 The number of panicles is found to be the least on the plot in which ground water irrigation is practised by the gravity flow method throughout all the growth stages of the rice plant. No significant difference is found between the other plots. \circled4 The number of spikelets per panicle at the various stages of rice growth at which_ surface or ground water is supplied by gravity flow method are as follows; surface water at all growth stages‥‥‥‥‥ 98.5. Ground water at all growth stages‥‥‥‥‥‥62.2 Ground water at the tillering stage‥‥‥‥‥ 82.6. Ground water at the reproductive stage ‥‥‥‥‥ 74.1. \circled5 Ripening percentage is about 70 percent on the test plot in which ground water irrigation is practised during all the growth stages and at the tillering stage only. However, when ground water irrigation is practised, at the reproductive stage, the ripening percentage is reduced to 50 percent. This means that 20 percent reduction in the ripening percentage by using ground water irrigation at the reproductive stage. \circled6 The weight of 1,000 kernels is found to show a similar tendency as in the case of ripening percentage i. e. the ground water irrigation during all the growth stages and at the reproductive stage results in a decreased weight of the 1,000 kernels. \circled7 The yield of brown rice from the various treatments are as follows; Gravity flow; Surface water at all growth stages‥‥‥‥‥‥514kg/10a. Ground water at all growth stages‥‥‥‥‥‥428kg/10a. Ground water at the reproductive stage‥‥‥‥‥‥430kg/10a. Standing water; Surface water at all growh stages‥‥‥‥‥‥556kg/10a. Ground water at all growth stages‥‥‥‥‥‥441kg/10a. Ground water at the reproductive stage‥‥‥‥‥‥450kg/10a. The above figures show that ground water irrigation by the gravity flow and by the standing water method during all the growth stages resulted in an 18 percent and a 21 percent decrease in the yield of brown rice, respectively, when compared with surface water irrigation. Also ground water irrigation by gravity flow and by standing water resulted in respective decreases in yield of 16 percent and 19 percent, compared with the surface irrigation method. 4. Results obtained from the experiments on the improvement of ground water irrigation efficiency to paddy rice are as follows; (1) When the standing water irrigation with surface water is practised, the daily average water temperature in a paddy field is 25.2$^{\circ}C$, but, when the gravity flow method is practised with the same irrigation water, the daily average water temperature is 24.5$^{\circ}C$. This means that the former is 0.7$^{\circ}C$ higher than the latter. On the other hand, when ground water is used, the daily water temperatures in a paddy field are respectively 21.$0^{\circ}C$ and 19.3$^{\circ}C$ by practising standing water and the gravity flow method. It can be seen that the former is approximately 1.$0^{\circ}C$ higher than the latter. (2) When the non-water-logged cultivation is practised, the yield of brown rice is 516.3kg/10a, while the yield of brown rice from ground water irrigation plot throughout the whole irrigation period and surface water irrigation plot are 446.3kg/10a and 556.4kg/10a, respectivelely. This means that there is no significant difference in yields between surface water irrigation practice and non-water-logged cultivation, and also means that non-water-logged cultivation results in a 12.6 percent increase in yield compared with the yield from the ground water irrigation plot. (3) The black and white coloring on the inside surface of the water warming ponds has no substantial effect on the temperature of the water. The average daily water temperatures of the various water warming ponds, having different depths, are expressed as Y=aX+b, while the daily average water temperatures at various depths in a water warming pond are expressed as Y=a(b)x (where Y: the daily average water temperature, a,b: constants depending on the type of water warming pond, X; water depth). As the depth of water warning pond is increased, the diurnal difference of the highest and the lowest water temperature is decreased, and also, the time at which the highest water temperature occurs, is delayed. (4) The degree of warming by using a polyethylene tube, 100m in length and 10cm in diameter, is 4~9$^{\circ}C$. Heat exchange rate of a polyethylene tube is 1.5 times higher than that or a water warming channel. The following equation expresses the water warming mechanism of a polyethylene tube where distance from the tube inlet, time in day and several climatic factors are given: {{{{ theta omega (dwt)= { a}_{0 } (1-e- { x} over { PHI v })+ { 2} atop { SUM from { { n}=1} { { a}_{n } } over { SQRT { 1+ {( n omega PHI) }^{2 } } } } LEFT { sin(n omega t+ { b}_{n }+ { tan}^{-1 }n omega PHI )-e- { x} over { PHI v }sin(n omega LEFT ( t- { x} over {v } RIGHT ) + { b}_{n }+ { tan}^{-1 }n omega PHI ) RIGHT } +e- { x} over { PHI v } theta i}}}}{{{{ { theta }_{$\infty$ }(t)= { { alpha theta }_{a }+ { theta }_{ w'} +(S- { B}_{s } ) { U}_{w } } over { beta } , PHI = { { cpDU}_{ omega } } over {4 beta } }}}} where $\theta$$\omega$; discharged water temperature($^{\circ}C$) $\theta$a; air temperature ($^{\circ}C$) $\theta$$\omega$';ponded water temperature($^{\circ}C$) s ; net solar radiation(ly/min) t ; time(tadian) x; tube length(cm) D; diameter(cm) ao,an,bn;constants determined from $\theta$$\omega$(t) varitation. cp; heat capacity of water(cal/$^{\circ}C$ ㎥) U,Ua; overall heat transfer coefficient(cal/$^{\circ}C$ $\textrm{cm}^2$ min-1) $\omega$;1 velocity of water in a polyethylene tube(cm/min) Bs ; heat exchange rate between water and soil(ly/min)

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2015년도 학술발표회
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• pp.238-238
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• 2015

There are demands for water environmental analysis of discharge processes in paddy fields, however, it is not fully understood in nutrients discharge process for watershed modeling. As hydrological processes both surface and ground water and agricultural water managements are so complex in paddy fields, the development of lowland paddy fields watershed model is more difficult than upland watershed model. In this research, the improvement of SWAT (Soil and Water Assessment Tool) model for a paddy watershed was conducted. First, modification of surface inundated process was developed in improved pot hole option. Those modification was evaluated by monitoring data. Second, the monitoring data in river and drainage channel in lowland paddy fields from 2012 to 2014 were analyzed to understand discharge characteristics. As a case study, Imbanuma basin, Japan, was chosen as typical land and water use in Asian countries. In this basin, lowland paddy fields are irrigated from river water using small pumps that were located in distribution within the watershed. Daily hydrological fluctuation was too complex to estimate. Then, to understand surface and ground water discharge characteristics in irrigation (Apr-Aug) and non-irrigation (Sep-Mar) period, the water and material balance analysis was conducted. The analysis was composed two parts, watershed and river channel blocks. As results of model simulation, output was satisfactory in NSE, but uncertainty was large. It would be coming from discharge process in return water. The river water and ground water in paddy fields were exchanged each other in 5.7% and 10.8% to river discharge in irrigation and non-irrigation periods, respectively. Through this exchange, nutrient loads were exchanged between river and paddy fields components. It suggested that discharge from paddy fields was not only responded to rainfall but dynamically related with river water table. In general, hydrological models is assumed that a discharge process is one way from watershed to river. However, in lowland paddy fields, discharge process is dynamically changed. This function of paddy fields showed that flood was mitigated and temporally held as storage in ground water. Then, it showed that water quality was changed in mitigated function in the water exchange process in lowland paddy fields. In future, it was expected that hydrological models for lowland paddy fields would be developed with this mitigation function.

• 한국관개배수논문집
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• 제21권1호
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• pp.118-126
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• 2014

In this study, the use of the spur of riverbank technique is being investigated. The spur of the riverbank typically reduces the velocity of flow and protects the embankments by increasing friction along the water and the banks. This also has an effect in the rise of water level upstream. It is also used for the rectification of riverside line and restoration of the waterway through sedimentation near the spur of the riverbank. In this study, physical-scaled experiments are conducted to investigate the process of creating a mild meandering channel using the spur of the riverbank with varying water flows and sedimentation functions. The hydraulics observations are taken with respect to the varying heights and length of the riverbank's spurs and the distance between each spur for the formation of the mild meandering channel. It is observed that for 1.06 times of the meander length, it requires 2 times of the interval with each spur of river width. Similarly, 1.25L times of the meander length, it requires 0.5 times of the interval with each spur of river width. The sand accumulation is induced by the spur of riverbank when the spur of riverbank's heights are more than 40% of water depth and the length of the spur of riverbank needs under than 20% of river width for avoid exaggerated sand accumulation in the center of channel.

• 원예과학기술지
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• 제29권3호
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• pp.201-210
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• 2011

This experiment was conducted to investigate physical and chemical characteristics by volume fractions of root media using peatmoss, perlite, and vermiculite, along with effects on the growth of pot chrysanthemums (Dendranthema ${\times}$ grandiflorum 'Vemini') in a C-channel mat irrigation system. To evaluate the physico-chemical properties of 20 root media, the bulk density, particle density, total pore space, pore space, ash content, organic matter, pH, and electrical conductivity were measured and data were analyzed using principal component analysis (PCA). PCA scores revealed that physico-chemical properties changed by the blending of peatmoss, perlite, and vermiculite. The 20 root media were divided into three main groups by hierarchical cluster analysis. At the end of the experiment, the pH and EC of the root media were measured from media divided into four layers. The pH of root media without plants showed a strong linear relationship and the pH of root media with plants increased exponentially. The change of EC in the root medium was indicated as a hyperbolic curve. Plant growth characteristics according to growth in the 20 root media were analyzed by PCA. It was found that the mixing ratios of the root media affected plant growth characteristics. Therefore, mixing ratio is an important factor for pot-plant production in a subirrigation system.

• 한국지형학회지
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• 제24권1호
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• pp.39-50
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• 2017

This study was conducted to analyze the variation of hydro-geomorphological environment along Baekgok wetland, which experiencing periodical inundation, in that water-level fluctuation of reservoir caused by irrigation. Since the field data is unavailable, modeling techniques, involving models such as HSPF and TELEMAC-2D, have been applied to simulate hydrological cycle in watershed and hydrodynamics in channel scale. The result of simulation indicates that the water-level of reservoir determines both the water surface extension and water depth in the wetland. Furthermore, it also shows that water-level functions as a spatial limit factor for a fluvial environment and woody vegetation such as willow. The fact of which the scale of water-level fluctuation being larger than an average topographical relief along the wetland can explain the result. While the water-level kept high, the wetland is submerged and waterbody becomes lentic. In contrast, while the water-level is lowered, fluvial phenomena of which being dependent on flow rate and channel shape become active. Hence, the valid fluvial process is likely to take place only for 4 months annually just near the channel, and it advances to a conclusion expecting a deposition to be dominant among the wetland except for such area. It is anticipated that such understanding can contribute to establishing plans to preserve the geomorphological and ecological value of the Baekgok wetland.

• 물과 미래
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• 제26권3호
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• pp.63-74
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• 1993

관개용 저수지의 퇴사량 추정을 위해 총 유실량-유사운송비법을 적용하고 대상 저수지의 유사 포착효율을 추정하는 것이 본 논문의 목적이다. 관개용 저수지 20개를 선정하여 실측자료를 구하고 도양유실량식(Universal Soil Loss Equation, USLE)를 이용하여 저수지 유역의 연평균 토양유실량을 산정하였다. 총토양유실량은 경사지 토양유실량과 하도 유실량으로부터 정의되며 유사운송비를 적용하여 저수지 유입유사량을 정하였다. 저수지 포착효율을 적용한 추정 저수지 퇴사량과 특정 퇴사량자룔를 비교한 결과 대체로 양호한 결과를 나타내었다. 저수지 포착효율은 퇴사량의 유입토사에 대한 비로서 본 연구의 결과가 Brune값과 비교하여 20% 정도의 오차를 보였으며 이를 개선한 관개용 저수지 포착효율 추정식을 제안하였다.

• 한국지역지리학회지
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• 제8권1호
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• pp.65-82
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• 2002

중국 사천분지 서부의 도강언 관개시설은 기원전 3세기에 진의 촉군 태수였던 이빙에 의하여 축조되었다. 이 시설은 대규모 거 관개의 효시로서 민강의 곡구에 입지한다. 이 지점은 이 지역에서 남쪽의 장강으로 합류하는 다른 강들의 곡구보다 해발고도가 높아 관개의 효율성이 크고, 강수량, 하계 등의 여건상 풍부한 유량을 지닌다. 이런 점에서 이 지점은 일찍이 거 관개시설의 입지로 선정되었다. 이 시설은 곡구에서 유수를 양분하는 '금강제'와 '어취', 유로변경을 위한 '보병구' 그리고 홍수와 토사를 배출하는 '비사언' 등으로 구성되었다. 이들은 상호 유기적으로 수재와 갈수 현상을 동시에 방지하였다. 여기에는 유수의 곡류현상과 침식, 운반. 퇴적작용, 그리고, 암석의 풍화과정 등의 원리가 이미 적용되었다. 한편 성도평원에는 개착된 10여 개 인공수로들의 일부가 동쪽의 부강 유역까지 이어졌었는데, 이 사실은 간과되어 왔다. 결국 이 시설은 민강을 수원으로 이 지역의 수전농업 발전을 주도함으로써 '천부지국'을 이주는 계기가 되었다.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.185-191
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• 1999

In a mean time, arrangement of a arable land is lead by government with same way, same type. It means that there are no considering on characteristic features of region and aspect of ecological environment that can experess its natural charactersistics. Because whenever there is needed to be arranging , most of structure are made by a ward office from a desgin to a execution so that cause many public resentment and durability is very short by a inappropriateness its maintenance. The purpose of this study is divided into four parts ; First, to form the naturally favorable waterside spaces by performing the basic water controlling funtions of the irrigation channel and the drainage channel. Second, to provide the meeting place of the residents and to restrore the ecological system by means of the formation of the naturally favorable waterside spaces. Third, to lead to the optimal design and maintenance that residents want by inviting the residents to participate at the begining stage of planning. A district of this study is located on Songsam(13-14 zone), Samseung-Lee Ganam-Meon Yeoujoo-Gun Jyonggi Province and a length of section is 420m. This study came up with the following results. First, estabished the type of design and area of the area by means of the collected residents' opinions. Seconds, changed the straight line water channel already designed to the curve water channel . Third changed the structure materials of the steel concrete structure to the natural materials . Fourth, change dthe design by area for the ecological system and the meeting place of the residents. Fifth, divided the whole area into fourth area in order to satisfy the residents' requests.