• Journal of Soil and Groundwater Environment
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• v.6 no.1
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• pp.45-52
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• 2001

This study investigated the effectiveness of ultrasonic waves on the relative permeability under a range of soil type, flushing rate, and sonication power. This study was conducted in the laboratory using a specially designed and fabricated equipment, and the laboratory study was simulated by ECLPISE 100 which is a commercial black oil simulator. The test results indicated the sonication increased contaminant extraction significantly. From analytical standpoint, sonication caused a change in the relative permeability of the test samples, a reduction in residual oil saturation and an increase in both irreducible water saturation and wettability. These three parameters are highly related with $(C_{10})^2$. The computer software ECLIPSE 100 can be used to analyze the change of the relative permeability due to sonication in two phase immiscible flow.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.11a
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• pp.277-282
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• 2004

This paper concerns about dynamic analysis of an underwater test miner, which operates on cohesive soil. The test miner consists of tracked vehicle and pick-up. device. The motion oj pick-up device relative to the vehicle chassis is controlled by two pairs of hydraulic cylinders. The test miner is modeled by means of a commercial software. A terramechanics model of cohesive soft soil is implemented to the software and applied to dynamic analysis of the test miner model. The dynamic responses of test miner are studied with respect to of four different types of terrain conditions.

• Geomechanics and Engineering
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• v.24 no.6
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• pp.599-610
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• 2021

Conduits are commonly installed below the ground for utility conveyance around the world. Vertical load on a buried conduit is an important parameter that needs to be known to ensure its safe design and installation. Consideration of soil arching in load calculations helps achieve a more realistic and efficient design. In the past, considering the arching effect, the design charts have been presented for use by practicing engineers to calculate the vertical load on the conduit buried below the level ground. There are currently no design charts for calculating the vertical load on the conduit buried under a sloping ground. In this paper, an attempt has been made to present the derivation of a generalized analytical expression considering that the soil mass overlying the conduit has a sloping face and the arching phenomenon takes place. The developed generalized expression has been used to present some design charts considering specific values of slope geometry, soil properties and burial depths. Furthermore, analytical results for specific soil parameters have been compared with the results extracted from a commercial software PLAXIS 2D, for a developed numerical model and an independent study.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.04a
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• pp.174-181
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• 2002

The paper presents an effective analytical method for SSI systems which can have separation or sliding at the soil-structure interface. The method is based on a hybrid approach which combines a linear SSI code KIESSI-2D in frequency domain with a commercial finite element package ANSYS to obtain nonlinear dynamic responses in time domain. The method is applied to a 2-D underground box structure which experiences separation and sliding at the soil-structure interface. Material nonlinearity of the concrete structure is also included in the analysis. Effects of the interface conditions are examined and some critical factors affecting the seismic performance of underground structures are identified.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.03a
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• pp.165-173
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• 2003

In this study, the applicability of currently used pipeline.soil interaction force and previously proposed analytical relationship for the response analysis of buried pipeline subjected to transverse permanent ground deformation (PGD) due to liquefaction is evaluated. Based on meaningful contemplation, the improvement of interaction force and proposition of analytical relationship is made. Improved interaction force includes various patterns of PGD or spatial distributions of interaction force caused by the decrease of soil stiffness, and proposed relationship based on improved formula is applicable without regard to the width of PGD. Through the comparison of numerical results by use of commercial FEM program, the rational applicability of proposed relationship is objectively confirmed.

• Geomechanics and Engineering
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• v.18 no.6
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• pp.639-650
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• 2019

Time-domain commercial codes are widely used to evaluate the seismic behavior of tunnels. Those tools offer a good insight into the performance and the failure mechanism of tunnels under earthquake loading. Viscous damping is generally employed in the dynamic analysis to consider damping at very small strains in some cases, and the Rayleigh damping is commonly used one. Many procedures to obtain the damping parameters have been proposed but they are seldom discussed. This paper illustrates the influence of the Rayleigh damping formulation on the tunnel visco-elastic behavior under earthquake. Four Rayleigh damping determination procedures and three soil shear velocity profiles are accounted for. The results show significant differences in the free-field and in the tunnel response caused by different procedures. The difference is somewhat decreased when the soil site fundamental frequency is increased. The conventional method which consists of using solely the first soil natural mode to determine the viscous damping parameters may lead to an unsafe seismic design of the tunnel. In general, using five times site fundamental frequency to obtain the damping formulation can provide relatively conservative results.

• Journal of Environmental Policy
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• v.3 no.1
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• pp.1-29
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• 2004

The role of the financial institution to promote corporate sustainability may be reviewed in two angles, as a commercial lender and an investor. As a commercial lender, financial institutions should minimize the legal risks and the political risks. Financial institutions began to recognize environmental risks as legal risks that directly affect their lending practices since the legislation of the Comprehensive Environmental Response, Compensation, and Liability Act("Superfund") of the U.S.A. The so-called lender liability rule has a detailed guideline where the financial institutions may be exempted from the Superfund Liability. Similar attempts are noticed in the recent EU White Paper on Environmental Liability. In Korea, comprehensive environmental liability laws are yet to be developed. The Soil Environment Preservation Act now includes a far-reaching environmental liability provisions, where the owners and operators as well as receivers of the facility bear responsibility. However, whether the financial institutions may be captured as a potential responsible party is not very clear. Until the relevant legislation is developed and court decisions accumulate, Korean financial institutions are well advised to raise awareness on this issue, to develop environmental policies and to train personnels.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.2
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• pp.108-111
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• 2005

A field study was conducted to develop an economically suitable combination of organic and inorganic fertilizers for sugarcane cultivation in sandy acidic soil of a commercial sugarcane farm under Old Himalayan Piedmont Plain of Bangladesh. Results revealed that the treatment $T_4$ which received $75\%$ of Recommended fertilizers (N 120, P 35, K 100, S 25, Zn 2 kg $ha^{-1}$) + 10 Mg $ha^{-1}$ Rice mill ash + Mg $ha^{-1}$ press mud significantly produced higher sugarcane yield (72.34 Mg $ha^{-1}$) among all the treatments except $T_5$ having $100\%$ of Recommended fertilizers + 10 Mg $ha^{-1}$ Rice mill ash + 10 Mg $ha^{-1}$ press mud, which was identical. $T_4$ also gave the highest net economic benefit at Bangladesh Taka 15,920.47 per hectare from the added nutrient management. Thus, the integrated use with organic and inorganic fertilizer is highly essential for sustainable production of sugarcane in commercial farm of the region in Bangladesh, where it has been grown year after year.

• Korean Journal of Environmental Agriculture
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• v.31 no.3
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• pp.217-223
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• 2012

BACKGROUND: Increase of heavy metals in agricultural ecosystem has become a social issue nationwide as it is related to public health. This study was performed to find out the status and long-term trends with consecutive application with the commercial liquid pig manure in the agricultural fields. METHODS AND RESULTS: Heavy metals including arsenic, cadmium, copper, lead, nickel, and zinc were analyzed in the 41 samples of paddy fields and 54 samples of upland fields consecutively applied with commercial liquid pig manure for 0 to 16 years. Heavy metal accumulation were not increased statistically at the both paddy and upland fields as the consecutive application year of commercial liquid pig manure were increased. However, some of surveyed upland soils exceeded the criteria of cadmium, copper, and zinc designated by the Soil Environmental Conservation Act in Korea. CONCLUSION: Therefore, analysis of heavy metals, specially copper and zinc, in agricultural fields is absolutely necessary before liquid pig manure application to the fields. In addition, heavy metal accumulation in agricultural fields following to the long-term application of liquid pig manure will be monitored periodically considering with bioavailability of copper and zinc to the crops as an essential nutrients.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.4
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• pp.337-345
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• 2022

For data such as rainfall and soil moisture, it is important to obtain the values of all points required as geostatistical data. Spatial interpolation is generally performed in this process, and commercial software such as ArcGIS is often used. However, commercial software has fatal drawbacks due to its high expertise and cost. In this study, R, an open source-based environment with ArcGIS, a commercial software, was used to compare the differences according to the processing environment when performing spatial interpolation. The data for spatial interpolation was weather forecast data calculated through Land-Atmosphere Modeling Package (LAMP)-WRF model, and soil moisture data calculated for each cumulative rainfall scenario. There was no difference in the output value in the two environments, but there was a difference in user interface and calculation time. The results of spatial interpolation work in the test bed showed that the average time required for R was 5 hours and 1 minute, and for ArcGIS, the average time required was 4 hours and 40 minutes, respectively, showing a difference of 7.5%. The results of this study are meaningful in that researchers can derive the same results in a commercial software environment and an open source-based environment, and can choose according to the researcher's environment and level.