• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.5
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• pp.113-121
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• 2012

The study was carried out to investigate the dimension of irrigation canal, and measure the water flow of those diverted from Kimje main canal in Dongjin irrigation area. The rating curves indicating the relationships between water level and discharge of the lateral canals were induced using the measured data with high regression coefficients of 0.957~0.999 at inlet points and 0.932~0.998 at end points, respectively. And Manning's roughness coefficients were estimated as the ranged from 0.015 to 0.074 at inlet points and 0.056 to 0.089 at end points with rectangular type of concrete open irrigation canals, the Manning's roughness coefficients of the end points were less than those values of the end points, which may be considered as the deposition of the bottom sediments.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.1
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• pp.109-114
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• 2012

Stage-discharge relationship is applied to convert water level into discharge at the auto-measuring station in many irrigation canals. The stage-discharge curve is very important for reliable application for the agricultural water management system. We made results of discharge measurement at 18 stations in the irrigation canal nearby the Idong reservoir from 2010 to 2011. Stage-discharge relationships for each 18 stations were drawn considering of different hydraulic and geometrical characteristics at each stations. R-squared over 0.91 at each stations show high reliability for application of these relationships.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.1
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• pp.11-18
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• 2012

This study was investigated agricultural water supply system of major agricultural waterway for Gimje canal, Jeongeup canal, Dongjin river conduit of Dongjin river basin. Furthermore, this result will be used for water resources and agricultural demand in Saemangeum reclaimed arable land. Annual precipitation for 5 years in Dongjin river basin was 1,311.7mm. The average discharges in Dongjin river basin was $1,390{\times}10^6\;m^3$ and $1,516{\times}10^6\;m^3$ and $744{\times}10^6\;m^3$ for 2,007 and 2008, respectively. Also, annual average amount of water resources was 1,861${\times}10^6\;m^3$ and $2,279{\times}10^6\;m^3$ and $1,227{\times}10^6\;m^3$ for 2,007 and 2008, respectively. Dongjin river basin water system for the analysis of agricultural water in water resources, runoff, agricultural water demand and usage surveys were analyzed, resulting in the total amount of water due to precipitation of the watershed of the $12.3{\times}10^9\;m^3$ ~$22.8{\times}10^9\;m^3$ and Dongjin River basin in waters flowing discharge is $7.4{\times}10^9\;m^3$~$16.1{\times}10^9\;m^3$, agricultural water demand and usage of each of $6.8{\times}10^9\;m^3$~$6.9{\times}10^9\;m^3$ and $4.9{\times}10^9\;m^3$~$7.1{\times}10^9\;m^3$ compared to the agricultural water demand was more likely. Agricultural water supply system in Dongjin river basin is complex because of devided branches to the main canal and branch canal. In this process, accurately assessment of water usage is very difficult. Therefore, systematic management of water resources and supply of agricultural water supply system to use the terms of the complexity and diversity by considering the appropriate level of agricultural water management systems will be needed. As a result of this study, it can be used water resources assessment in quantity, rational usefulness and basic planning of water resources development for water distribution.

• Magazine of the Korean Society of Agricultural Engineers
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• v.52 no.2
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• pp.87-96
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• 2010

• KCID journal
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• v.7 no.1
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• pp.19-26
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• 2000

The irrigation water supply and water quality from a pumping station were surveyed. Guiseok pumping station was selected as a monitoring site. Water level in irrigation canal was monitored continuously and water samples were taken and analyzed, periodical

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.56-60
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• 2005

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.

• Restorative Dentistry and Endodontics
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• v.22 no.1
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• pp.111-131
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• 1997

Eighty two of extracted bovine mandibular incisors were sectioned transversely through the cementoenamel junction(CEJ) and instrumented to a size minimum-# 110 file at the working length by 5.25 % NaOCl irrigation. The roots in group 1 were received a final irrigation with 10ml of 17% EDTA followed by 10ml of 5.25% NaOCl, group 2, 10ml of 40% citric acid followed by 10ml of 5.25% NaOCl, group 3, 20ml of 5.25% NaOCl, and control group, 20ml distilled water. Canal walls of four roots in each group and control group were examined by SEM(x3000). Calcium hydroxide was placed into all experimental roots except control group. Each root was placed in nalgen bottle containing unbuffered distilled water. The pH level of the medium surrounding tooth was recorded at 0, one hour, and daily for 1week, then 14days, 21days, and 28days using pH electrode. At 1, 3, 7, 14, 21days, and 28days, four roots from each group were split longitudinally and the ratio change was recorded using spectroiluorometer. The results were followings : 1. The smear layer was totally removed from canal walls in group 1 and 2, but was observed in group 3 and control group. 2. The hydroxyl ion diffused more rapidly through radicular dentin when smear layer was removed from canal walls. 3. The hydroxyl ion derived from calcium hydroxide began to diffuse from the root canal to the exterior surface of the root at 1day, and continued to 1-2weeks. 4. The pH level of dentin near the CEJ was not different in all experimental group regardless of presence of smear layer. It is clinically advisable to place calcium hydroxide into root canal for 1-2weeks for the purpose of expectation of diffusion of hydroxyl ion. But, after the placement of calcium hydroxide into root canal, the consequent pH level of external root surface will be futher studied with respect to it's effect on the root and periodontium.

• Journal of Korean Society of Rural Planning
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• v.6 no.2 s.12
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• pp.73-81
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• 2000

This study was carried out to measure the amount of outlet discharge and analyse the water quality from an agricultural reservoir. Joongpyong reservoir was selected as the monitoring site. Daily discharge was determined by measured water level data of delivery canal and the stage-discharge relation curve. The measured water discharge through culvert outlet of Joongpyong reservoir was 593,200m3 which was equivalent to irrigation depth 1,186mm during irrigation period in 1999. And water samples were taken from the surface water of reservoir and delivery canal, periodically. Temporal variation of water quality constituents such as water temperature, pH, EC, total nitrogen, total phosphorus were investigated. The result showed that pH was ranged 6.9 7.8, total nitrogen 1.39 4.11mg/L, total phosphorus 0.007 0.036 mg/L, respectively.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.4 no.2
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• pp.35-43
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• 1984

The purpose of this paper is to develop a mathematical model which can be used to compute the position of the free surface due to water level fluctuations in the canal and the transient pressure distributions along the canal lining. The diagnostic equation has been solved by the point successive over-relaxation method, and the linearized prognostic equation has been solved by the implicit Lax-Wendroff scheme. Four different cases in the simulation conditions are presented for both permeable and impermeable canal lining to predict the transient seepage surface development.

• Proceedings of the KACD Conference
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• 2003.11a
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• pp.587-589
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• 2003

I. Objectives The purpose of this study was to evaluate the effects of EDTA on microhardness of roor canal dentine according to different working time. II. Materials and Methods Forty recently extracted, intact single root teeth were used. Debris and soft tissue remnants on the root surface were cleaned with scaler and stored in saline at $4^{\circ}C$ until used. All selected roots were similar in size and shape. 1. Preparation of teeth. The crown of the teeth were removed at the level of the CEJ, using a water-cooled diamond bur.(omitted)