• Journal of the Society of Naval Architects of Korea
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• v.40 no.3
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• pp.29-36
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• 2003

In rough seas, bow-flare regions of the fine ships (container ship and PCC) are subject to high impact pressures due to the bow-flare slamming. And many ships suffer structural damages in that region, even though they were built under the bow structure strengthening rules of the ship classes. So, a new design method for bow-flare structure is highly required. In this paper, a new prediction method of the bow-flare impact pressure (in terms of equivalent static pressure) acting on the fine ships' bow is presented. This method is based on the 11 fine ships' damage analysis and the mechanisms of water entry impact and breaking wave impact. Calculation results of the bow-flare impact pressure and the shell plate thickness are shown and discussed. Through the example calculations, it was found that the present method is useful for the structure design of the fine ships' bow.

• Journal of the Society of Naval Architects of Korea
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• v.40 no.3
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• pp.22-28
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• 2003

In rough seas, bow-flare regions of the full ships (tanker and bulk carrier) are subiect to high impact pressures due to the on-coming breaking waves. And many ships suffer structural damages in that region, even though they were built under the bow structure strengthening rules of the ship classes. So, a new design method for bow-flare structure is highly required. In this paper, a new prediction method of the bow-flare impact pressure (in terms of equivalent static pressure) acting on the full ships' bow is presented. This method is based on the 6 full ships' damage analysis and the breaking wave impact mechanism. Calculation results of the bow-flare impact pressure and the shell plate thickness are shown and discussed. Through the example calculations, it was found that the present method is useful for the structure design of the full ships' bow.

• Journal of Environmental Impact Assessment
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• v.3 no.2
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• pp.69-75
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• 1994

Environmental Impact Assessment is composed of screening, scoping, inventory survey, prediction, assessment, alternative assessment, mitigation measure, and post management. Environmental monitoring data is applied to EIA process such as prediction and post management. It must he collected and managed systematically for effective applying in EIA process. This article explains factors such as air quality, water quality, soil, ocean, odor, noise & vibration, ecosystem, etc. and organizations of environmental monitoring managed by Ministry of Environment.

• Journal of Environmental Impact Assessment
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• v.4 no.3
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• pp.31-39
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• 1995

Environmental Impact Assessment (EIA) is composed of various procedures, such as screening, scoping, inventory survey, prediction, assessment, alternative assessment, mitigation measures, and post management. Environmental monitoring data for air quality or water quality, etc. is applied in the EIA process, especially in prediction and post management. As an effective tool of environmental monitoring, the remote sensing method, introduced recently, was used in collecting nationwide data concerning ecosystem and land use. This article explains the current monitoring status in Korea. Monitoring factors include air quality, water quality, soil, ocean, odor, noise, and ecosystems. This report explains the organization of the environmental monitoring system managed by the Ministry of Environment in Korea. Furthermore, it shows the environmental criteria and environmental policies applied to EIA in Korea.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.5
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• pp.1134-1143
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• 1994

A study of adiabatic shear band formation and propagation of 4340 steel was done using the stepped speciment which was subjected to high velocity impact. The high velocity impact was performed on compression Hopkinson bar impact machine. After the controlled impact, the specimen was prepared for visual inspection. Numerical simulation was also performed with same geometrical dimension using explicit time integration finite element code. Experimental results were then compared with the numerical prediction. It was found that the numerical prediction is quite accurate, average thickness of adiabatic shear band is about $10{\mu}m$, the macro crack around shoulder is due to folding, and the deformation control ring is effective to freeze the propagation of adiabatic shear band.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.66-70
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• 2005

Noise prediction are required as part of an environmental impact assessment. Prediction method that is used to domestic environmental impact assessment of construction site and industrial site is not applied work operation rate, work position, moving noise source, inner traffic flow, work type and height of noise source etc. The BS5228 methodology is used mainly for assessment of proposed open industrial sites(mineral extraction, landfill etc.), and larger long-term construction sites(typically for major infrastructure projects). also, estimation which consider various effect factor is possible.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.381-384
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• 2005

The purpose of this study is to develop a prediction model for evaluating heavy-weight floor impact sounds in a test building. Three rooms in the test building (slab thickness In and 240mm), which consist of frame concrete structures were tested and modeled. First, the SPL distribution in the receiving room was analyzed by measuring SPL at 90 positions using a bang machine. Then, a vibration model using finite element method is proposed considering the material properties and boundary conditions. In addition, the result of transient analysis was compared with field measurements using a standard heavy-weight impact source. Through a vibro-acoustic simulation program, an acoustic model evaluating the building elements (reflected wall, nor, window and door) was proposed. Finally, validation of the prediction model was conducted by vibro-acoustic analysis with field measurements of noise radiation characteristics in receiving rooms.

• Smart Media Journal
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• v.12 no.10
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• pp.47-54
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• 2023

As understanding sudden climate change and agricultural productivity becomes increasingly important due to global warming, soil moisture prediction is emerging as a key topic in agriculture. Soil moisture has a significant impact on crop growth and health, and proper management and accurate prediction are key factors in improving agricultural productivity and resource management. For this reason, soil moisture prediction is receiving great attention in agricultural and environmental fields. In this paper, we collected and analyzed open field environmental data using a pilot field through random forest, a machine learning algorithm, obtained the correlation between data characteristics and soil moisture, and compared the actual and predicted values of soil moisture. As a result of the comparison, the prediction rate was about 92%. It was confirmed that the accuracy was . If soil moisture prediction is carried out by adding crop growth data variables through future research, key information such as crop growth speed and appropriate irrigation timing according to soil moisture can be accurately controlled to increase crop quality and improve productivity and water management efficiency. It is expected that this will have a positive impact on resource efficiency.

• Journal of Environmental Impact Assessment
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• v.33 no.2
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• pp.84-98
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• 2024

This study proposed a prediction equation for the estimation of blasting vibaration and blasting noise, utilizing 320 datasets for the blasting vibration and blasting noise acquired during urban blasting works in the Incheon, Suwon, Wonju, and Yangsan regions. The proposed blasting vibration prediction equation, derived from regression analysis, indicated correlation coefficients of 0.879 and 0.890 for SRSD and CRSD, respectively, with an R² value exceeding 0.7. In the case of the blasting noise prediction equation, stepwise regression analysis yielded a correlation coefficient of 0.911 between the prediction values and real measurements for the blasting nosie, and further analysis to determine the constant value revealed a correlation coefficient of 0.881, with an R² value also exceeding 0.7. These results suggest the feasibility of applying the proposed prediction equations when environmental impact assessments or education environment evaluation according to urban development or apartment construction projects is performed.

• Journal of Environmental Impact Assessment
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• v.21 no.5
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• pp.767-779
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• 2012

In case of executing surveys in marine ecosystems, the most important things are scientific selection measures of survey stations that can represent various ecosystems characteristics in subjected areas. The situations show a lot of differences that understand characteristics of marine ecosystems in targeted areas according to selection methods and positions in survey stations. Investigation ranges and station numbers in marine ecosystems are classified according to project characteristics and scales. But, currently a clear divisions or objective standards are not. Therefore, this study tried to provide selection measures of survey station in scientific and objective marine ecosystems through precise analysis among environmental impact statements of coastal development projects until now. In this study, impact scopes of marine ecosystems correspond to physical impact predictions by undertaking projects. Impact ranges were divided into three(physical impact ranges) coastal waters. In case of proposing numbers of survey stations according to this survey ranges, numbers of investigation stations due to minimum survey scopes in targeted projects applied 20~30% of all numbers in survey stations. Number of survey stations due to average investigation scopes within physical impact ranges applied 60~70% of all numbers in investigation stations. Numbers of survey stations due to maximum survey ranges within physical impact scopes applied 10~20% of all numbers in survey stations. So, improvement measures were deducted. Finally, according to prediction ranges in impact of various coastal development projects, several kinds of conclusions are suggested. And, it is thought to be able to use as fundamental database to select investigation stations in marine organisms through this study.