• Journal of the Society of Naval Architects of Korea
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• v.49 no.6
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• pp.469-477
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• 2012

This paper describes the characteristic analysis of ice impact force for the Arctic structure shape. In the present study an energy method has been used to predict the impact force during the ice-structure collision. This study also employs two concepts for reference contact area and normalized stress in analysis procedure. The influences of factors, such as impact velocity, full penetration depth, structure shape and ice floe size, are investigated. Full penetration occurs, particularly at lower impact velocity when ice thickness increase. But "typical size" ice floe does not expected ever to achieve full penetration during the impact procedure. The structure shape is the dominant factor in ice impact force characteristic. The results for various ice-structure collision scenarios are analyzed.

• Journal of Environmental Impact Assessment
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• v.7 no.2
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• pp.1-3
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• 1998

• International Journal of Ocean System Engineering
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• v.2 no.3
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• pp.151-159
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• 2012

The characteristics of an impact load and pressure were experimentally investigated. Drop tests were carried out using a modified Wigley with CB = 0.56. The vertical force, pressures, and vertical accelerations were measured. A 6-component load cell was used to measure the forces, piezo-electric sensors were used to capture the impact pressure, and strain-gauge type accelerometers were used to measure the vertical accelerations. A 50-kHz sampling rate was applied to capture the peak values. The repeatability of the measured data was confirmed and the basic characteristics of the impact load and pressure such as the linearity to the falling height were observed for all of the measurements. A simple formula was derived to extract the physical impact load from the measured force based on a simple mass-sensor-mass diagram, which was validated by comparing impact forces with existing data using the mathematical model of Faltinsen and Chezhian (2005). The effects of the elasticity of the model and change in acceleration during the water entry were investigated. It is interesting to observe that the impact loads occurred and reached peak values at the same time duration after water entry for all drop heights.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.6
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• pp.1353-1362
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• 2012

Many studies have demonstrated that articles from international collaborations are more cited than articles from domestic collaborations. However, difference between the citation impact of international and domestic co-authored papers is supposed to be widened due to the collaboration strategy adopted by individual institute. In short, each institute will show the significantly different citation impact between international and domestic co-authored papers. In this paper, we applied the index of Incremental Ciation Impact(ICI) to identify the different value of citation impact between international and domestic co-authored papers for research institutes of KRCF, results of which will be understood under the strategy of international research collaboration.

• Nuclear Engineering and Technology
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• v.53 no.4
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• pp.1199-1209
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• 2021

The detection of unexpected loose parts in the primary coolant system in a nuclear power plant remains an extremely important issue. It is essential to develop a methodology for the localization and mass estimation of loose parts owing to the high prediction error of conventional methods. An effective approach is presented for the localization and mass estimation of a loose part using machine-learning and deep-learning algorithms. First, a methodology was developed to estimate both the impact location and the mass of a loose part at the same times in a real structure in which geometric changes exist. Second, an impact database was constructed through a series of impact finite-element analyses (FEAs). Then, impact parameter prediction modes were generated for localization and mass estimation of a simulated metallic loose part using machine-learning algorithms (artificial neural network, Gaussian process, and support vector machine) and a deep-learning algorithm (convolutional neural network). The usefulness of the methodology was validated through blind tests, and the noise effect of the training data was also investigated. The high performance obtained in this study shows that the proposed methodology using an FEA-based database and deep learning is useful for localization and mass estimation of loose parts on site.

• Journal of Environmental Impact Assessment
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• v.18 no.3
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• pp.185-193
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• 2009

This study documented and diagnosed the status and problems of coastal dredging and offshore disposal of dredged sediments in South Korea to improve assessment procedures for marine environmental impacts and develop effective management systems. A total of $729({\times}10^6)m^3$ of coastal sediment was dredged in the harbors during the period of 2001-2008. Most of dredged sediment was disposed to the land dumping sites whereas ocean disposal accounted for less than 5%. Ocean disposal areas were especially concentrated to the exclusive economic zone (EEZ) in the southeast of Busan, which is not only an important fishing area for fishermen, but also considered to be spawning and nursery ground for some commercial fish species. To minimize negative impacts of dredging and ocean disposal of coastal sediment on marine ecosystem and potential strife among coastal users, we suggest 1) in development projects involving ocean disposal, it should be mandatory to propose careful reuse plans in the land, and 2) guidelines of environmental assessment and consequence management programs should be developed and implemented.

• The Journal of Information Systems
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• v.22 no.4
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• pp.49-69
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• 2013

Recently, enterprises have reinforced security control in order to prevent infringement of personal information and abuse of customer information by insiders. However, the reinforcement of security control by enterprises makes it difficult for internal users to perform business by using a business information system. There is, therefore, a need for research on various fields, which makes it possible to establish an appropriate security control policy while minimizing an impact on business. The present research verifies and analyzes an impact on difficulty in business of internal users using customer information, which is caused by security control performed by display restriction on customer information identifiers. The present research is intended to academically develop a technique for statistically analyzing an impact degree and a causal relationship between security control and an impact on business, which is a dichotomous variable, and to practically contribute to the establishment of an efficient security policy in consideration of an impact on business when an enterprise applies security control. A research target was internal business information systems of domestic securities enterprises, data was collected by questionnaire, and verification/analysis was performed by logistic regression analysis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.5
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• pp.399-404
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• 2008

This paper proposes revisions in the law governing assessments of the environmental impact of marine projects. In particular, we suggest strengthening the consultative role of the Ministry for Food, Agriculture, Forestry and Fisheries (MIFAFF), the agency responsible for regulating coastal area utilization and development, in order to improve the system by which fishery resources are managed, thus preventing negative environmental impact. Moreover, such an improved impact assessment statement would include reasonable evaluations of the dispersion of pollutants, such as the suspended solids generated by construction projects, as well as of the dredging, dumping and sand mining involved in coastal area reclamation. Thus, public confidence in the latter would be increased by the development and implementation of standardized and consistent guidelines addressing environmental research, simulation processes and evaluations of data.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.3
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• pp.209-216
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• 2021

This study aim is to examine 1) the impact of corporate social responsibility disclosure and tax aggressiveness on firm value, 2) the impact of tax aggressiveness on firm value, and 3) the impact of corporate social responsibility on firm value. The sample of this study is 29 manufacturing companies listed on the Indonesia Stock Exchange. The period of research spans three years, from 2017 to 2019. The data is gathered from the annual report of the companies or website of companies and also the website from Indonesia Stock Exchange (IDX). This study uses Structural Equation Model with Partial Least Square. The research findings show that corporate social responsibility and tax aggressiveness have a negative and significant impact on firm value. The tax aggressiveness and firm value have a negative and significant impact. Corporate social responsibility has a positive and significant impact on firm value. This study uses the manufacturing sector, so that the findings of this study cannot be generalized to other sectors. Future research should explore other sectors such as mining, banking, etc. This study uses Effective Tax Rate (ETR) to measure tax aggressiveness. Further research should use another measurement, for instance, Current Effective Tax Rate (CETR).

• Journal of the Korean Society for Railway
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• v.16 no.5
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• pp.365-371
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• 2013

This study describes impact test methods for a rolling-stock windscreen executed in Korea and Europe. Air-pressurized impact test equipment for the front windscreens of high speed trains was designed and manufactured. The equipment is capable of launching a projectile at 500km/h, in accordance with EN 15152's impact test method. Calibration of the test equipment was conducted to find an equation relating air pressure and projectile velocity. Specimens ($1000mm{\times}700mm$) having similar specifications with the front windscreens in metro and conventional trains were used to conduct impact tests with this equipment to research the impact characteristics of the screens according to the impact velocity.