• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.1
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• pp.10-16
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• 2018

The Republic of Korea Marine Corps is planning to develop a new amphibious assault vehicle which is able to operate with higher water speed than current KAAV. In order to achieve a higher water speed for hydrodynamically bulff-body vehicles, it is essential to develop drag reduction strategies. In this paper, resistance characteristics including trim angles of amphibious assault vehicles with several appendage designs are investigated using a commercial CFD code, STAR-CCM+. The computed results are compared with experimental data conducted at the towing tank with 1:4.5 scaled model and show good correlation. Comparing with the results of bare hull, 3.4 % of hydrodynamic drag and 52 % of trim angle are reduced by the application of double angled bow flap and a hydrofoil attached at the transom.

• Safety and Health at Work
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• v.13 no.2
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• pp.235-239
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• 2022

Background: The purpose of present study was to determine the effectiveness of training program based on job stress management in NEDSA and line staff. Methods: The study method of this study was quantitative and quasi-experimental research Methods: From the statistical population (all employees of the NEDSA and line staff in 2020-2021), 30 of these people were selected by judgmental sampling method and considering the inclusion and exclusion criteria. The participants were first matched based on age and education and were randomly divided into experimental and control groups. First, pre-test was taken from both groups (Job Stress Questionnaire). The experimental group was presented with a job stress management training package and no protocol was presented in the control group. After the sessions, post-test was received from both groups (experimental and control). After two months, a follow-up test was performed. Results: The results were entered into SPSS-24 software and analyzed. The results of repeated measure showed high effectiveness of the job stress management package (researcher-made). The results showed that the job stress management training package showed 67.5% effectiveness and also the training effect of job stress management training was stable for two months (follow-up). Conclusion: Based on these results, Training program based on stress management can be effective in military staff.

• Journal of the Society of Naval Architects of Korea
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• v.57 no.4
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• pp.241-253
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• 2020

The Small-Unit Riverine Craft (SURC) is a small high-speed vessel used by navies and marine corps in relatively shallow waterway environments, such as riverine areas or littoral coasts. In the past, SURCs have primarily been rigid-hulled inflatable boats constructed using composite materials such as glass fiber reinforced plastics. More recently, single-hull SURCs have been manufactured using aluminum for weight reduction. In this study, a Carbon Fiber Reinforced Polymer (CFRP) material was applied instead to examine its feasibility in the basic design of an SURC with a hull length of 10 m. The CFRP structural design was obtained using the properties of a marine CFRP laminate, determined in a previous study. Next, the designed CFRP SURC was modeled to confirm its functionality, then compared with existing aluminum SURCs, indicating that the CFRP SURC was 41.49 % lighter, reduced fuel consumption by 30 %, and could sail 50 NM further for every hour of engine operation. A method for reducing the high cost of carbon fiber was also proposed based on the adjustment of the carbon fiber content to provide the optimum strength where required. The data developed in this study can be used as a basis for further design of CFRP craft.

• Strategy21
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• s.45
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• pp.148-187
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• 2019

This paper is to analyse the necessity and development direction of the ROK's maritime security strategy white paper. To this end the paper is composed of 5 chapters titled introduction; the necessity of the ROK's maritime security strategy white paper; the ROK's actual situation in relation to maritime security strategy and cases of major advanced oceanic countries; the vision, goals, strategic tasks, and implementation system of the ROK's 'national maritime security strategy'; and conclusion. The achievement of the national marine strategic vision, such as the 'Ocean G5,' is of course possible when Korea can maintain and strengthen the maritime safety and maritime security of the people. The Sewol Ferry incident reminds us that we need a 'national maritime security strategy white paper' like the advanced marine countries. In order for the national maritime security strategy to be carried our efficiently, as in advanced oceanic countries, mere should be a dedicated department with sufficient authority and status to mobilize the cooperation of related organizations including naval-coastal cooperation. It would be good to set up a tentatively named Maritime Security Council, an organization of minister-level officials involved under the National Security Council, and an executive body composed of working-level officials from related ministries. In order to successfully carry out the national maritime security strategy for the maritime safety and maritime security of the people like the United States and the United Kingdom, we need to further strengthen our domestic cooperation and cooperation system, international cooperation, and maritime security. We have to promote the establishment and promotion of maritime security strategies by the Navy; strengthening the operational link between the Navy and the Coast Guard; strengthening the maritime surveillance capability at the national level, and promoting sharing with the private sector, etc.

• Journal of the Korean Society for Marine Environment & Energy
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• v.12 no.2
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• pp.84-90
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• 2009

We incubated marine columnar sediments at $25^{\circ}C$ for 230 days to simulate the responses of phosphorus in the sediment which was exposed to freshwater. The incubation was composed of three different treatments (FW: freshwater, FWA: freshwater under anoxic condition, and SW: seawater as a Control). Six particulate fractions of phosphorus in sediment were obtained through sequential extraction and, for comparison, phosphate concentrations in porewater and superlying water were also determined. After the incubation, evidently higher concentrations of phosphate were found in FW and FWA compared to SW. Mass extinction of living organisms in marine sediment from freshwater shock and consequent decay of their corps probably contributed such high phosphate spike in the overlying water. Higher concentrations of BD-P(lron-bound P) were found in FW compared to SW. After exposure to the freshwater, we could determine that penetration depth of dissolved oxygen in marine sediment will be deeper. A result of increases of ferrous compounds in freshwater where contained less sulfide has been obtained. Because of these phenomena, BD-P was increased in FW. On the contrary, BD-P was decreased in FWA since poor dissolved oxygen concentration. In FWA, total amount of Leachable P(SUM of LOP) has been remarkably increased through the experiment, which strongly suggested the easy conversion of the leachable P into reactive P. This experiment has shown that most of diverse P species in marine sediment were leachable under freshwater and low oxygen condition. Therefore reclamation of natural tidalfalt and consequent freshwater introduction seems to trigger the conversion of diverse P-species to leachable P in the marine sediments, which will exert high benthic load of phosphate to the overlying water.

• Strategy21
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• s.42
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• pp.83-113
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• 2017

After defeat in World War II, Japan's Peace Constitution committed the country to forego the acquisition of offensive military capabilities. However, in the midst of the post-cold war period, Japan began to change its security posture in line with the so-called 'normal state theory', which called for a more robust defense posture and expanded security activities. The second Abe administration promoted these security policies by issuing a National Security Strategy as well as a new National Defense Program Outline(NDPO) in 2013 and by establishing new security institutions such as the National Security Council. The Abe administration also adopted the new concept of a 'Unified Mobile Defense Force' in the 2013 which replaced the 'Dynamic Defense Force' as a new criteria for the Self-Defense Force's acquisition of military capabilities. In this new concept of military capabilities, the Ground Self-Defense Force is planning to replace existing divisions with mobile divisions and to form 'Amphibious Rapid Deployment Bridge' for the first time in 2018, which has long been taboo in Japan. Japan has experience a Marine Corps in the past. Likewise, an offensive changes in the military strategy can change the spectrum of strategy and 'Amphibious Rapid Deployment Bridge' plays a big role in this. Furthermore, Japan is increasing the Coast Guard's budget and capabilities in preparation for contingencies around the Senkaku islands (called the Diaoyu in Chinese). The South Korea navy should utilize Japan's changing security posture to deter immediate threat such as North Korea's military provocations and potential enemy threat such as China, Japan, Russia.

• Convergence Security Journal
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• v.18 no.5_2
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• pp.61-71
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• 2018

The ROK military, with changes in the environment. Furthermore, soldiers in their new generation, who have remote difference in their views and characters with former generation. This study attempts to confirm the effects of Coaching Leadership on the military life satisfaction, focused on the Platoon soldiers of ROK Marine Corps. For a more realistic study, the research model is designed through prior studies; Coaching Leadership are set as independent variables; military life satisfaction is selected as dependent variables and Self-efficacy is defined as a mediating variable. A questionnaire survey has been conducted on 1,450 soldiers, including all forces and all branch of ROKMC, January 18 to 25 February, 2016. Analysis were performed using SPSS/WIN 23.0. As a result, First, Coaching Leadership had positively significant with military life satisfaction and Self-efficacy. Second, Self-efficacy had significant effects on the military life satisfaction. Third, Self-efficacy was proven to have a partial mediating effect in the relationship between coaching leadership and military life satisfaction. Based on the results, the theoretical and practical implications of the research findings are discussed, and recommendation for future research are provided.

• Korean Journal of Heritage: History & Science
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• v.47 no.4
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• pp.192-209
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• 2014

The important national cultural heritages were retrieved. April 25 2014, US President Barack Obama formally returned 9 Seals of Joseon Dynasty and Korean Empire in Korea-US Summit taken place in Cheong Wa Dae. These Seals were taken out of Deoksugung illegally by a US Marine Corps officer during Korean War, handed down to his posterity, and last November 2013 confiscated by HSI in San Diego. Through investigations above facts turned out and it was decided to return these relics to Koera. In the process of surveying these seals, I confimed the authenticity of them and transferred my opinion to Cultural Heritage Administration. In this paper, I try to summarize the historical value of each Seals and suggest the remaining task.

• Strategy21
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• s.31
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• pp.57-84
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• 2013

North Korea's continuous threats and provocative behaviors have aggravated tension on the Korean peninsula particularly with the recent nuclear weapons test. South Korea's best way to cope with this situation is to maintain the balance among three policy directions: dialogue, sanctions, and deterrence. Among the three, I argue that deterrence should be prioritized. There are different sources of deterrence such as military power, economic power, and diplomatic clouts. States can build deterrence capability independently. Alternatively, they may do so through relations with other states including alliances, bilateral relations, or multilateral relations in the international community. What South Korea needs most urgently is to maintain deterrence against North Korea's local provocations through the enhancement of independent military capability particularly by addressing the asymmetric vulnerability between militaries of the South and the North. Most of all, the South Korean government should recognize the seriousness of the negative consequences that North Korea's 'Nuclear shadow strategy' would bring about for the inter-Korea relations and security situations in Northeast Asia. Based on this understanding, it should develop an 'assertive deterrence strategy' that emphasizes 'multi-purpose, multi-stage, and tailored deterrence whose main idea lies in punitive retaliation.' This deterrence strategy requires a flexible targeting policy and a variety of retaliatory measures capable of taking out all targets in North Korea. At the same time, the force structures of the army, the air force, and the navy should be improved in a way that maximizes their deterrence capability. For example, the army should work on expanding the guided missile command and the special forces command and reforming the reserve forces. The navy and the air force should increase striking capabilities including air-to-ground, ship-to-ground, and submarine-to-ground strikes to a great extent. The marine corps can enhance its deterrence capability by changing the force structure from the stationary defense-oriented one that would have to suffer some degree of troop attrition at the early stage of hostilities to the one that focuses on 'counteroffensive landing operations.' The government should continue efforts for defense reform in order to obtain these capabilities while building the 'Korean-style triad system' that consists of advanced air, ground, and surface/ subsurface weapon systems. Besides these measures, South Korea should start to acquire a minimum level of nuclear potential within the legal boundary that the international law defines. For this, South Korea should withdraw from the Nuclear Non-proliferation Treaty. Moreover, it should obtain the right to process and enrich uranium through changing the U.S.-South Korea nuclear cooperation treaty. Whether or not we should be armed with nuclear weapons should not be understood in terms of "all or nothing." We should consider an 'in-between' option as the Japanese case proves. With regard to the wartime OPCON transition, we need to re-consider the timing of the transition as an effort to demonstrate the costliness of North Korea's provocative behaviors. If impossible, South Korea should take measures to make the Strategic Alliance 2015 serve as a persisting deterrence system against North Korea. As the last point, all the following governments of South Korea should keep in mind that continuing reconciliatory efforts should always be pursued along with other security policies toward North Korea.

• Korean Journal of Culture and Social Issue
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• v.16 no.4
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• pp.469-485
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• 2010

The present research investigated the influence of the enlistment motivation on an image of military organization, soldier's stress, a confidence of social life after discharge from military service and military life satisfaction in Korean military service. Participants of this research were 257 soldiers (121 conscript Army soldiers and 136 voluntary Marines) from 2 companies in the army and 2 companies in the Marine Corps located in South Korea. Results of this study showed that 1) conscript Army group(M=2.39, SD=.71)had a significantly higher score than voluntary Marines group(M=1.95, SD=.63)in extrinsic enlistment motivation. On the contrary, Marines group(M=4.16, SD=.76) had a significantly higher score than Army group(M=3.62, SD=.87) in intrinsic enlistment motivation. 2) Enlistment by intrinsic motivation has positive influence on the military life. Result of Regression analysis showed that enlistment by intrinsic motivation significantly predicted a military life satisfaction(𝛽=.402, t=6.424, p<.001), a confidence of social life(𝛽=.528, t=9.836, p<.001), and an image of military organization(𝛽=.494, t=8.486, p<.001). On the other hand, enlistment by extrinsic motivation has negative influence on the military life. Result of Regression analysis showed that enlistment by extrinsic motivation significantly predicted the soldier's stress in military life(𝛽=.415, t=6.642, p<.001), and no confidence of social life(𝛽=-.177, t=-3.306, p<.001). These results suggest that Korean military needs to focus on enhancing intrinsic enlistment motivation of young men of conscription age before conscription by educating, and advertising etc. And also, we discuss that Korean military needs to consider how to boost intrinsic motivation of military life.