• Structural Engineering and Mechanics
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• v.77 no.4
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• pp.441-461
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• 2021

Reinforced concrete (RC) columns are crucial in building structures and they are of higher vulnerability to terrorist threat than any other structural elements. Thus it is of great interest and necessity to achieve a comprehensive understanding of the possible responses of RC columns when exposed to high intensive blast loads. The primary objective of this study is to derive analytical formulas to assess vulnerability of RC columns using an advanced numerical modelling approach. This investigation is necessary as the effect of blast loads would be minimal to the RC structure if the explosive charge is located at the safe standoff distance from the main columns in the building and therefore minimizes the chance of disastrous collapse of the RC columns. In the current research, finite element model is developed for RC columns using LS-DYNA program that includes a comprehensive discussion of the material models, element formulation, boundary condition and loading methods. Numerical model is validated to aid in the study of RC column testing against the explosion field test results. Residual capacity of RC column is selected as damage criteria. Intensive investigations using Arbitrary Lagrangian Eulerian (ALE) methodology are then implemented to evaluate the influence of scaled distance, column dimension, concrete and steel reinforcement properties and axial load index on the vulnerability of RC columns. The generated empirical formulae can be used by the designers to predict a damage degree of new column design when consider explosive loads. With an extensive knowledge on the vulnerability assessment of RC structures under blast explosion, advancement to the convention design of structural elements can be achieved to improve the column survivability, while reducing the lethality of explosive attack and in turn providing a safer environment for the public.

• Nuclear Engineering and Technology
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• v.54 no.6
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• pp.2230-2243
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• 2022

The tin tailing processing industry in Malaysia has operated with minimal regard and awareness for material management and working environment safety, impacting the environment and workers in aspects of radiation and heavy metal exposure. RIA was conducted where environmental samples were analyzed, revealing concentrations of ²²⁶Ra, ²³²Th and ⁴⁰K between the range of 0.1-10.0, 0.0-25.7, and 0.1-5.8 Bq/g respectively, resulting in the AED exceeding UNCEAR recommended value and regulation limit enforced by AELB (1 mSv/y). Ra_eq calculated indicates that samples collected pose a significant threat to human health from gamma-ray exposure. Assessment of heavy metal content via pollution indices of soil and sediment showed significant contamination and enrichment from processing activities conducted. As and Fe were two of the highest metals exposed both via soil ingestion with an average of 4.6 × 10^-3 mg/kg-day and 1.4 × 10^-4 mg/kg-day, and dermal contact with an average of 5.6 × 10^-4 mg/kg-day and 6.0 × 10^-4. mg/kg-day respectively. Exposure via accidental ingestion of soil and sediment could potentially cause adverse non-carcinogenic and carcinogenic health effect towards workers in the industry. Correlation analysis indicates the presence of a relationship between the concentration of NORM and trace elements.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.27 no.1
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• pp.55-70
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• 2024

The loss of biodiversity poses a significant threat not only to business sustainability and investment risk but also to societal well-being. Nature serves as a crucial driver for long-term business viability and economic prosperity. The Task Force on Nature-related Financial Disclosures (TNFD), established in September 2023, mandates that companies assess and disclose their impacts on nature. Despite this, many businesses lack a full understanding of their reliance on and impact upon natural capital and ecosystem services, leading to insufficient disclosures. This study evaluates the applicability of TNFD's assessment methodologies and indicators within a domestic context, highlighting the condition of nature and ecosystem services, and exploring potential synergies with national biodiversity policies. Our analysis suggests that TNFD necessitates a unique approach to the spatial and temporal data and methodologies traditionally employed in environmental impact assessments. This includes assessing the reciprocal influences of corporate activities on natural capital and ecosystem services via the LEAP framework. Moreover, in industries where the choice of specific indicators depends on unique sectoral traits, developing a standardized strategy for data and assessment indicators-adapted to local conditions-is crucial due to the variability in the availability of assessment tools and data. The proactive engagement of the private sector in ecosystem restoration projects is particularly promising for contributing towards national biodiversity objectives. Although TNFD is in its nascent phase, its global adoption by numerous companies signifies its potential impact. Successful implementation of TNFD is anticipated to deepen businesses' and financial institutions' understanding of natural capital and ecosystem services, thereby reinforcing their commitment to sustainable development.

• Journal of Environmental Impact Assessment
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• v.31 no.2
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• pp.95-105
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• 2022

Busan, where the coastal ecosystem health is deteriorating due to high development pressure and intensity of use, needs ecosystem management that considers humans and the natural environment together for sustainable use and ecosystem preservation of the coastal areas. In this study, the InVEST model was applied to assess the habitat status of the coastal land and coastal sea to manage the ecosystem based on habitats. As a result of the assessment of the coastal land, the habitat quality of Gadeok-do, Igidae, and Sinseondae, Gijang-gun are high, and Seo-gu, Jung-gu, Dong-gu, and Suyeong-gu are low. In the case of the coastal sea, the habitat risk of the Nakdong river estuary is low, and some areas of Yeongdo-gu, Saha-gu, Gangseo-gu are high. Therefore, for the sustainable use and preservation of coastal ecosystems, it is necessary to prepare ecosystem-based management measures to improve damaged habitats and reduce threats. In addition, the impact on coastal seas should be fully considered when planning coastal land development. The results of the InVEST habitat quality model in coastal land show similar tendencies to the biotope and environmental conservation value assessment map. The results of the habitat risk assessment in the coastal sea are expected to be utilized to identify habitats in the coastal sea and management of threat factors.

• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.4
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• pp.65-74
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• 2017

North Korea is one of the high vulnerable countries facing the threat of natural disaster and has experienced more frequent disasters in recent years. These disasters have significantly led to food shortages and large reductions in crop yields. In 2015, both North Korean officials and international agencies had identified the extreme drought event, the worst in one hundred years according to the North Korean government. The objective of this study was an assessment of the extreme drought events in 2014~2015, and to apply climatic drought indices for drought monitoring in North Korea. Characteristics of the extreme drought in North Korea are examined by using the weekly-based Standardized Precipitation Evapotranspiration Index (SPEI). The drought characteristics illustrated by the SPEI results are compared with a Standardized Precipitation Index (SPI) results and drought impact information to understand how these indices can explain the drought conditions within the country. These results demonstrated that the SPEI could be an effective tool to provide improved spatial and temporal drought conditions to inform management decisions for drought policy.

• Journal of Internet Computing and Services
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• v.21 no.2
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• pp.73-80
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• 2020

Due to the expansion of cyber space, war patterns are also changing from traditional warfare to cyber warfare. Cyber warfare is the use of computer technology to disrupt the activities of nations and organizations, especially in the defense sector. However, the defense against effective cyber threat environment is inadequate. To complement this, a new cyber warfare operation concept is needed. In this paper, we study the concepts of cyber intelligence surveillance reconnaissance, active defense and response, combat damage assessment, and command control in order to carry out cyber operations effectively. In addition, this paper proposes the concept of cyber warfare operation that can achieve a continuous strategic advantage in cyber battlefield.

• Fire Science and Engineering
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• v.34 no.1
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• pp.89-102
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• 2020

Chemical terrorism using toxic and flammable gases, which could be fatal to the health of the human body, poses a serious threat to the security of most advanced countries, as well as those that are suffering from local disputes, due to the asymmetric information that exists between terrorist actors and victims. The countermeasures against chemical terrorism can be roughly divided into three stages: prevention, response, and probation. The critical factors for each professional response agency, and the personnel that determine the degree and range of chemical terrorism damage, are performing missions successfully in the process of the prevention and the response stage against chemical terrorism. To do this, conducting objective and systematical assessments on facilities that could potentially be the subject of chemical terrorism is more important than anything. In this study, we compared the existing domestic and foreign vulnerable classification systems for chemical terrorism, reviewed the current direction of improvement in domestic classification systems, and suggested more scientific and systematic methodologies through the vulnerability assessment on an actual public facility sample.

• Journal of Environmental Impact Assessment
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• v.22 no.5
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• pp.481-489
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• 2013

There are U.S. troops with a force about 290,000 strong stationed all around the world, approximately 150 countries. Among the troops, USFK has performed principal part with its stationing for 50 years against the military threat of North Korea. However, as a result of an investigation made into environmental contamination of several bases which were restituted from US to ROK by the Land Partnership Plan in the process of relocation of USFK, it was found that the area was contaminated by not only TPH and BTEX caused by diesel fuel and JP-8 but also various heavy metal over the standard level according to the operations of corps. Among these bases, 4 corps, each of which has different duties and function, were chosen to be analyzed for the characteristics and degrees of soil contamination. Fisrt of all, in armored camp the soil was contaminated by TPH and heavy metal (Zn, Ni, Pb) due to the repairing activities of tracked vehicles and shooting exercises. In army aviation camp, the soil was contaminated by TPH, BTEX and heavy metal (Zn, Cd) due to repairing activities of aircrafts. Also, in engineer camp there was contaminated area polluted by TPH and heavy metal (Zn, Pb) caused by open-air storage of various construction materials and TPH, BTEX and heavy metal (Zn, Pb, Cu) contamination of aircraft shooting area in shooting range camp were detected. Managing environment will be more effective when we identify the contaminative characteristics and take necessary measures in advance.

• Journal of Digital Convergence
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• v.9 no.6
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• pp.153-163
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• 2011

This study analyzes the military and political factors that influenced the Participatory Government's resolution in Wartime Operational Control (OPCON) Transition. The research on key factors in OPCON transition firstly implemented literature research and then increased feasibility through additional use of AHP. The analysis results showed that there was a negative effect for Korean Peninsular Defense in the 'ROK-US Alliance Asymmetry' area, a positive effect to increase ROK-led Capability of Theater Operation in the 'ROK and U.S. Alliance Interdependence' area and a positive effect for Invocation of ROK Self-Defense Power in the 'Interests of Participatory Government's Liberal Regime' area respectively. After applying AHP, "ROK exercise of Self-defense" in the 'Interests of Participatory Government's Liberal Regime' area received the highest assessment, while the "Increasement of North Korea's Threat" in the 'ROK-US Alliance Asymmetry' area received the lowest assessment. This study is meaningful in that it analyzed the key military and political factors in the Participatory Government's resolution of Wartime OPCON Transition using AHP.

• The Journal of Fisheries Business Administration
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• v.49 no.4
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• pp.99-108
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• 2018

Maintaining a certain level of fisheries production is due to the increase in aquaculture production. In recent years, aquaculture plays an important role in fishery production in Korea. Nevertheless, aquaculture should be carefully managed by regulations because it also causes environmental load which can threat sustainability of aquaculture. For this reason, Korean government has regulated density of culturing facilities with the Fisheries Law and its adjective decrees. The regulatory compliance of fisheries businesses is very low because the criteria for the regulation of the density were not enacted with scientific research. Thus, this research was aimed to obtain scientific criteria for the regulation of oyster aquaculture in Jaran Bay with economic assessment. For this research, we collected the data necessary for the assessment on five investigation points in the bay for two years. With the data, simulation for the growth rate of oyster was performed and the result showed that at least 25.5% of facilities should be reduced. Also, it was revealed that removing 2 long lines would be most beneficial. The NPV of the best measurement was 35,120,300 won and IRR was 11.7%. With this research, the government will gain more accurate regulatory compliance due to the scientific approach. Moreover, fisheries businesses in oyster aquaculture can obtain flexibility to cope with market fluctuation.