• Journal of Korean Society of Forest Science
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• v.96 no.3
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• pp.300-306
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• 2007

This study was carried out to analyze the characteristics of forest environmental and stream morphological factors by using the quantification theory (I) for prediction of the suitable dam site. The results obtained from this study were summarized as follows; The selection of suitable site for erosion control dam was estimated by normalized score of each category. And the prediction method of suitable site for erosion control dam divided into class I (Very suitable site), II (Suitable site), and III (Poor suitable site) for the convenience of use. In conclusion, if we select the suitable site for construction of erosion control dam for disaster prevention, we could save the loss of tremendous budget, avoid the poor suitable site due to subjective judgment, and it would promote the functions of erosion control dam.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.5
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• pp.695-701
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• 1999

Thermal sprayed Ni-Cr alloy coating on the carbon steel was carried out erosion-corrosion test and electrochemical corrosion test in the marine environment. THe erosion-corrosion behavior and electrochemical corrosion characteristics of substrate(SS400) and thermal sprayed Ni-Cr coating was investigated, The erosion-corrosion control efficiency of Ni-Cr coating to substrate was also estimated quantitatively.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.5
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• pp.85-96
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• 2003

The Revised Universal Soil Loss Equation (RUSLE) has been used in over 100 countries to estimate potential long-term soil erosion from the field. However, the RUSLE estimated soil erosion cannot be used to estimate the sediment delivered to the stream networks. For an effective erosion control, it is necessary to compute sediment delivery ratio (SDR) for watershed and sediment yield at watershed outlet. Thus, the Sediment Assessment Tool for Effective Erosion Control (SATEEC) was developed in this study to compute the sediment yield at any point in the watershed. To compute spatially distributed sediment yield map, the RUSLE was first integrated with the ArcView GIS and three area based sediment delivery ratio methods were incorporated in the SATEEC. The SATEEC was applied to the Bangdong watershed, Chuncheon, Gangwon Province to demonstrate how it can be used to estimate soil loss and sediment yield for a watershed. The sediment yield using USDA SDR method is 8,544 ton/year and 4,949 ton/year with the method by Boyce. Thus, use of watershed specific SDR is highly recommended when comparing the estimated sediment yield with the measured sediment data. The SATEEC was applied with hypothetical cropping scenario and it was found that the SATEEC can be used to assess the impacts of different management on the sediment delivered to the stream networks and to find the sediment source areas for a reach of interest. The SATEEC is an efficient tool to find the best erosion control practices with its easy-to-use interface.

• Journal of Korean Society of Forest Science
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• v.111 no.2
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• pp.276-286
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• 2022

We carried out this study to provide basic data necessary to establish a management plan for concrete erosion control dams in the future by analyzing results of detailed inspections of aged dams conducted in accordance with 「Guidelines for the Maintenance of the Erosion Control Facility」. We analyzed the results of a detailed inspection of 54 concrete erosion control dams which had been built over 20 years previously, located in private forests of Gyeongsangbuk-do using statistical methods. Having conducted exterior defect investigations, we found 18 dams (33.4%) in need of repair or follow-up measures and 15 dams in which the overall grade was changed due to investigator's corrections; we therefore considered that standardization of related standards and indicators would be necessary. After conducting concrete compression strength tests, we found 19 dams (35.2%) to be below the standard value of 21 MPa, and in particular, we included, in grade A, eight dams which we judged to be in good condition as a result of the exterior defect inspection. There was little clear correlation between the total score and the compressive strength of concrete, but there was a statistically significant difference in the compressive strength by overall grade. After analyzing the changes in the characteristics of the erosion control dams according to the elapsed years after construction, we detected no particular trend in the changes of total score and compressive strength over time. However, the cumulative ratio of the dams that required repair and follow-up measures and the dams below the compression strength standard had a strong positive linear relationship over time, suggesting that it would be possible to identify the aging characteristics of concrete erosion control dams.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.632-636
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• 2005

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.

• Journal of Korean Society on Water Environment
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• v.23 no.4
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• pp.518-526
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• 2007

There have been serious soil erosion and water pollution problems caused by highland agriculture practices at Doam-dam watershed. Especially agricultural activities, chemical and organic fertilizer and pesticide applications, soil reconditioning to maintain soil fertility are known as primary causes of soil erosion and water qaulity degradation in the receiving water bodies. Among these, soil reconditioning can accelerate soil erosion rates. To develop soil erosion prevention practices, it is necessary to estimate the soil erosion from the watershed. Thus, the Universal Soil Loss Equation (USLE) model has been developed and utilized to assess soil erosion. However, the USLE model cannot be used at watershed scale because it does not consider sediment delivery ratio (SDR) for watershed application. For this reason, the Sediment Assessment Tool for Effective Erosion Control (SA TEEC) was developed to assess the sediment yield at any point in the watershed. The USLE-based SA TEEC system can estimate the SDR using area-based SDR and slope-based SDR module. In this study, the SATEEC system was used to estimate soil erosion and sediment yield at the Doam-dam watershed using the soil properties from reconditioned agricultural fields. Based on the soil sampling and analysis, the US LE K factor was calculated and used in the SA TEEC system to analyze the possible errors of previous USLE application studies using soil properties from the digital soil map, and compared with that using soil properties obtained in this study. The estimated soil erosion at the Doam-dam watershed without using soil properties obtained in the soil sampling and analysis is 1,791,400 ton/year (123 ton/ha/year), while the soil erosion amount is 2,429,900 ton/year (166.8 ton/ha/year) with the use of soil properties from the soil sampling and analysis. There is 35 % increase in estimated soil erosion and sediment yield with the use of soil properties from soil reconditioned agricultural fields. Since significant amount of soil erosion are known to be occurring from the agricultural fields, the soil erosion and sediment yield from only agricultural fields was assessed. The soil erosion rate is 45.9 ton/ha/year without considering soil properties from soil reconditioned agricultural fields, while 105.3 ton/ha/year after considering soil properties obtained in this study, increased in 129%. This study shows that it is very important to use correct soil properties to assess soil erosion and sediment yield simulation. It is recommended that further studies are needed to develop environment friendly soil reconditioning method should be developed and implemented to decrease the speed of soil erosion rates and water quality degradation.

• Tribology and Lubricants
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• v.11 no.1
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• pp.58-65
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• 1995

When marine lubricating oil began to be emulsified and oxidized through ingressive water that have leaked from cooling pump seal systems, cooler, purifier system and piping system, the cavitation erosion-corrosion in alloy metals of bearings remains to the various troublesome problem at effective engine performance. Therefore, applied the cathodic protection to the control test of cavitation erosion-corrosion, and appointed the marine system oil containing 3% sea water as test environments, with different conductibility. Also, used the piezoelectric vibrator with 20 KHz, 24 $\mu$m as the cavity generation apparatus, and examined the weight loss, potential value, current density etc. in specimens with those condition. According to this testing data, investigated influence of cathodic protection on the control characteristics of cavitation erosion-corrosion, and will serve those as an elementary design data of marine bearing.

• Journal of Preventive Medicine and Public Health
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• v.15 no.1
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• pp.83-87
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• 1982

Acid erosion of teeth was studied in two factories. The A was the textile factory possessing dyeing process using acids. The B was the metal product manufactoring factory possessing electroplating process. The control group was selected at the same factory not exposed to acids. The results were summarized as below. 1. The pH of saliva was the range of $6.6{\sim}6.8$ in both factories. 2. The prevalence rate of erosion of teeth was higher in case group at the B. It was statistically significant. 3. The rate of erosion of incisor were the range of $12%{\sim}16%$(case group), $7%{\sim}21%$(control group) at the A and $10%{\sim}20%$ (case group), $2%{\sim}15%$ (control group) at the B. 4. The rate of erosion of degree 3 which is necessary for conforming, owing to occupational induction, were 8.9% (incisor: A) and 6.8% (incisor: B).

• Journal of agriculture & life science
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• v.52 no.6
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• pp.1-12
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• 2018

This study was conducted to analyze the openness of erosion control dams situated near mountain stream. The ecological functions of erosion control dams analyzed by such openness for adequately protect and manage the diversity of species and to prevent disasters. The obtained results were as follows. When structurally modifying or changing non-permeable, gravity type dams with a passing rate of less than 1% into open-type dams, the passing rate increased by about 77 times more from 0.72% to 55.8%. Except for closed, gravity type erosion control dams that are constructed with a special purpose such as creating sand deposits and reservoirs, there is a need to construct and improve the dams into permeable type dams that can relatively satisfactorily perform various functions such as carrying soil and sand to the downstream region and create a ecological corridor upstream and downstream for fish and amphibians. The openness based on the blocking height of the erosion control dam varies depending upon the height of the base part and the depth of the substructural part. It must be designed based on the on-site conditions and the purpose of the construction. The functional types of erosion control dams based on the open form of the cross-section as follows: the fish traffic type, flood control type, reservoir type for forest fire control), non-permeability type for soil and rock blocking, net type for blocking the rock flow and the particle screen type.

• Journal of Korean Society on Water Environment
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• v.26 no.4
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• pp.637-647
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• 2010

The Universal Soil Loss Equation (USLE)-based modeling systems have been widely used to simulate soil erosion studies. However the GIS-based USLE modeling systems have limitation in gully erosion evaluation which is one of the most important factor in soil erosion estimation. In this study, the integrated soil erosion evaluation system using with Sediment Assessment Tool for Effective Erosion Control (SATEEC) system, nLS and Unit Stream Power-based Erosion/Deposition (USPED) model was developed to simulate gully erosion. Gully head location using nLS model, USPED for gully erosion, and the SATEEC estimated sheet and rill erosion were evaluated and combined together with the integrated soil erosion evaluation system. This system was applied to the Haean-myeon watershed, annual average sediment-yield considering sheet, rill and gully erosion was simulated as 101,933 ton/year at the study watershed. if the integrated soil erosion evaluation system is calibrated and validated with the measured data, this system could be efficiently used in developing site-specific soil erosion best management system to reduce soil erosion and muddy water inflow into the receiving waterbody.