• Journal of the Korean GEO-environmental Society
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• v.12 no.5
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• pp.5-12
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• 2011

Water content is one of the significant engineering properties of soil for predicting the behavior of soil matrix. Conventional drying oven can be widely used to obtain the values by drying the soil specimens for 16 to 24 hours at $105^{\circ}C$. Although a number of experimental data has been accumulated for the conventional method of drying soil for water contents, shortcomings of the method are still hard to overcome such as long drying time for in situ use and the difficulty of taking prompt actions against emergency cases. Recently, ASTM and JGS have established microwave oven drying techniques for obtaining water contents to cope with those problems. And the reliability evaluation study has been also performed on the microwave oven drying for water contents. Feasibility study of the microwave oven drying was performed to confirm the process of the technique with Jumunjin sand, kaolinite, bentonite, weathered granite soil, and organic soil. Investigation was also conducted on the factors affecting and enhancing the reliability of the technique.

• Journal of The Geomorphological Association of Korea
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• v.24 no.1
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• pp.105-116
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• 2017

This article is written in the viewpoint of landscape ecological geography. The coast of South Chung-chong Province will make new characters of region in the development strategies program. This study is to describe geomorphological landscapes of South Chung-chong Province relating with it's environment based on the coast. Although landforms constitute prominent landscape features as tidal flats and rock cliff do, it is nonetheless the features such as beaches, sanddunes, and coastal plains that have various ramifications for human communities. Tidal flats, beaches and coastal sanddunes are special in that their formation is attributable to the combined action of tidal flows, waves and winds. To some extent, the erosion of sand has been a global phenomenon. Human impact are involved. The influence of globalization and expansion of liberal trade appears in regions variously. Individual regions need to secure its competitiveness in the world market. Regions are not value-neutral abstract conception, but must be informal commercialized characters of region. The coast of South Chung-chong Province has experienced rapid and dramatic changes. In industrial times, the middle of west coast Korea turned into a major reclamation at larger scale. Reclaimed land was based on location of industry and mechanized agriculture. The west coast highway and bridges between island and land contributed to the development of west coast transportation. As information society matured, trend and value are changing. Environment and ecology emphasize and rediscover the value of tidal flats and sanddunes. The west coast region now receives attention as eco-tour and sustainable course.

• Maritime Security
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• v.1 no.1
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• pp.61-92
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• 2020

This paper attempts to examine the changes in China's naval strategy and to analyze the goal, range, and method of each strategy during the Xi Jinping's era. Since the founding of New China, the People's Liberation of Army Navy(PLAN) has made four changes in the naval strategy. Under Xi Jinping's administration, China's naval strategy is far seas operation combined with near seas active defense. Now, China's naval strateg y is shifting from a defensive to an aggressive one, increasing the proportion of offensive weapon systems and the number of state-of-the-art warships, and the scope of the naval strategy has been specified in the second island chain including the Indian Ocean. With the changes of naval strategy, the PLAN will set a new strategic goal to secure maritime dominance and implement an assertive strategy to actively respond to the intervention and intrusion of external forces. Moreover, the PLAN will also improve its sea-based deterrence force and the maneuver force to block other countries in the long-distance maritime conflict zones. The operation method of China's future naval strateg y will gradually shift from 'interdiction' to 'rapid-response.'

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.3
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• pp.329-339
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• 2021

The monthly variation in species composition of fishes in the Gujora and Mangchi coastal waters in Geoje, Korea, was investigated between June 2018 and May 2019 through monthly fish collections using a gill net. A total of 46 species, numbering 410 individuals weighing a total of 96,645.0 g, were collected during the study period. The dominant species in terms of numbers were Chelidonichthys spinosus, Stephanolepis cirrhifer, Ditrema temmincki, Sillago japonica, Sebastes inermis, and Paraplagusia japonica. The number and biomass of fishes peaked in July. The peak in species diversity indices occurred in September. The cluster analysis revealed that there were four groups of fishes depending on the season. In addition, subtropical fishes were recorded in the study area, indicating the gradual subtropicalization of the coast of Geoje. Furthermore, the need to understand the changes in marine ecosystems owing to subtropicalization through continuous monitoring is emphasized.

• Journal of Environmental Impact Assessment
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• v.30 no.1
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• pp.24-34
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• 2021

Many countries have established and implemented marine ecosystem management plans to solve various problems arising from excessive development and use of marine and coastal areas. In this study, network analysis was applied to compare and understand marine ecosystem management's direction and characteristics in Korea and other maritime countries. The results showed that the words 'strengthen,' 'promote,' 'improve,' and 'establish' were the keywords used a lot in domestic and foreign marine ecosystem management plans. Establishing a foundation for marine ecosystem management, establishing international cooperation and partnerships, and strengthening climate change adaptation was commonly included. However, there were some differences in detailed management plans. In foreign countries, it aims to present management measures for certain species and improve the existing institutional foundation. Still, in Korea, it aims to strengthen the comprehensive management of marine life and establish an institutional foundation for marine ecosystems. This study is expected to help understand the direction of domestic and overseas marine ecosystem management and establish a domestic marine ecosystem management plan in the future.

• Journal of Advanced Navigation Technology
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• v.24 no.6
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• pp.601-606
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• 2020

In this paper, we designed a microstrip patch antenna that can be applied to the Wimax/LTE 5G system among wireless media usable in coastal ships. The substrate of the proposed antenna is FR-4 (er=4.3), the size is 22 mm × 30 mm, and it can be used in the 3.5 GHz and 5.8 GHz bands of Wimax/LTE 5G by constructing a simple structure using a microstrip patch antenna. CST Microwave Studio 2014 was used for simulation, and the gain of the simulation result is 2.41dB at 2.4 GHz and 3.96 dB at 3.5 GHz. S-Parameter also showed a result of less than -10 dB (VSWR 2:1) in the desired frequency band, and designed a small variable and a miniaturized antenna so that the antenna can be used in mobile phones or electronic devices.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.1
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• pp.1-12
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• 2021

The International Maritime Organization (IMO) is promoting the introduction of e-Navigation that prevents maritime accidents by fusion of Information & Communication Technology (ICT) with ship operation technology. In Korea, Korean e-Navigation is also being developed for fishing vessels and small vessels sailing offshore, which are vulnerable to maritime accidents. However, for the successful development of Korean e-Navigation, it is necessary to develop an indicator that can evaluate the development performance so that the development performance that has been progressed so far can be evaluated and the development direction can be re-established. Therefore, this study attempted to develop an evaluation index tailored to the development goal of e-Navigation service centering on the collision accident, which is a major maritime accident. In this study, a collision accident evaluation index for e-Navigation service was developed by deriving and quantifying the root cause of maritime collision accidents using Root cause analysis(RCA) and fault tree analysis (FTA) techniques. This indicator is considered to be helpful in reducing maritime accidents as it is used as a development indicator for e-Navigation and an indicator for maritime collision accident analysis.

• Korean Journal of Ichthyology
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• v.33 no.4
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• pp.273-277
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• 2021

The feeding habits of the pointhead flounder, Cleisthenes pinetorum were studied in the West Sea in Korea. The samples were investigated using 360 specimens (21.7~48.1 cm in total length) collected by gill net of the coastal waters from January to December 2019. As a result, C. pinetorum consumed mainly Ophiuroidea and Pisces, but also ate small amounts of Macrura, Echinodermata, Amphipoda and Brachyura. The results of this study showed a difference with those of main feed habits of C. pinetorum caught in the coastal waters of Kori (Huh and Baeck, 2003). The proportion of fishes in prey items increased with size-related while that of Ophiuroidea decreased. As total length of C. pinetorum increased the mean number of preys per stomach (mN/ST) and weight of prey per stomach (mW/ST) tended to increase.

• Journal of the Society of Disaster Information
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• v.18 no.1
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• pp.194-201
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• 2022

Purpose: This study investigated the relationship between climate factors and the catches in Korean offshore fisheries in recent three decades (1981 to 2010). Method: This study focused on seven types of fish species preferred in Korean cuisine. In the study, 10-year moving averages were used so that long-term trends could be easily identified. Results: Both air temperature and sea surface temperature (SST) on the coast of Korea rose in the period (p < 0.05). The rise in SST was significantly correlated with the rise in air temperature (p < 0.05), but not with precipitation. In the 2010s compared to in the 1981, catches of anchovy and squid greatly increased (p < 0.05), while catches of Alaska / walleye pollock has been almost extinct over the past 30 years. As such, cold-water fish species decreased or disappeared, and their fishing ground was replaced by warm-water fish species. Conclusions: These findings indicate that fish species caught in offshore fisheries of Korea have changed due to climate change, especially warming. This suggests that the warming of the Korean Peninsula may have a significant impact on the supply of fishery products and food security to Koreans in the near future.

• Maritime Security
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• v.3 no.1
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• pp.1-44
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• 2021

China's new Maritime Policy Law (MPL) purports to regulate the duties of China's maritime police agencies, including the China Coast Guard, and safeguard China's sovereignty, security, and rights and interest. The MPL has potentially far-reaching application, as China claims extensive maritime areas off its mainland and in the South China Sea. This expansive application of maritime law enforcement jurisdiction is problematic given that most of China's maritime claims are inconsistent with international law. To the extent that the MPL purports to assert jurisdiction over foreign flagged vessels in disputed areas or on the high seas, it contravenes international law. Numerous provisions of the MPL regarding the use of force are also inconsistent with international rules and standards governing the use of maritime law enforcement jurisdiction, as well as the UN Charter's prohibition on the threat or use of force against the territorial integrity or political independence of any state. China could use the MPL as a subterfuge to advance its illegal territorial and maritime claims in the South and East China Seas and interfere with coastal State resource rights in their respective exclusive economic zone.